Moderately intense physical exercise alleviates electrocardiographic changes induced by cisplatin in rats.

1. INTRODUCTION AND OBJECTIVE: Cisplatin induces many collateral effects such as gastrointestinal disorders, nephrotoxicity, and dysautonomia. Recently our group showed that cisplatin treatment induces gastric emptying delay and that physical exercise and treatment with pyridostigmine prevent this change. In the current study, we investigated the role of moderate exercise on cardiac activity and autonomic balance in rats treated with cisplatin. 2. METHODS: Male Wistar rats were divided into Saline, Cisplatin, Exercise, and Exercise+Cisplatin groups. Cardiac and autonomic disorders were induced by (Cisplatin-3mg/kg, i.p once a week/per 5 weeks). Exercise consists of swimming (1 hour per day/5x day per week/per 5 weeks without overload). Forty-eight hours after the last session of the training or treatment, we assessed the cardiac activity and HRV via electrocardiogram analysis in DII derivation. 3. RESULTS: Cisplatin increase (p<0.05) R-R´ interval and decrease (p<0.05) heart rate vs. saline. Exercise+Cisplatin prevented (p<0.05) changes in R-R´ interval. Exercise per se induced bradycardia vs. saline group. We observed an increase in LF (nu) and a decrease in HF (nu) in the cisplatin group vs. saline. These changes were not significant. Moreover, cisplatin treatment increased (P<0.05) QT, QTc, and JT intervals compared with the saline group. In the Exercise+Cisplatin groups these increases were prevented significantly (p<0.05). 4. CONCLUSION: In the current study, chronic use of cisplatin induced electrocardiographic changes without altering autonomic balance. Moderate physical exercise prevented this phenomenon indicating that exercise can be beneficial in patients in chemotherapy.

Use of scanning electron microscopy in the cochlea of guinea pigs.

INTRODUCTION: The use of electron microscopy in the study of the inner ear has allowed us to observe minute details of the hair cells, especially in ototoxicity studies; however, the preparation of this material is a difficult and delicate task. In an attempt to simplify the handling of these materials, two agents, toluidine blue and ethylenediamine tetra-acetic acid were tested, in addition to the elimination of osmium tetroxide during the preparation of albino guinea pig cochleae. We also tested the applicability of these methodologies in an ototoxicity protocol. OBJECTIVE: To verify the quality of the images obtained with and without the use of ethylenediamine tetra-acetic acid, toluidine blue and osmium tetroxide in the preparation of cochleae of albino guinea pigs for the scanning electron microscopy. METHODS: Three groups of cochleae were used. In Group 1, 10 cochleae were prepared with the usual methodology, dissecting the optical capsule without decalcification and using osmium tetroxide as a post-fixative agent. In Group 2, we prepared 10 cochleae decalcified with ethylenediamine tetra-acetic acid, injecting toluidine blue in the endolymphatic space to facilitate the identification of the organ of Corti. In Group 3, we used 4 cochleae of guinea pigs that received 3 doses of cisplatin (7.5mg/kg, D1-D5-D6), two prepared according to the methodology used in Group 1 and two with that used in Group 2. Scanning electron microscopy images were obtained from the organ of Corti region of the basal turn of each cochlea. RESULTS: The organ of Corti was more easily identified with the use of toluidine blue. The dissection of the cochlea was more accurate in the decalcified cochleae. The quality of the images and the preservation of the organ of Corti obtained with the two methodologies were similar. CONCLUSION: The proposed modifications resulted in images of similar quality as those observed using the traditional methodology.

A comparison of cisplatin cumulative dose and cisplatin schedule in patients treated with concurrent chemo-radiotherapy in nasopharyngeal carcinoma.

INTRODUCTION: Three-weekly cisplatin dose is accepted for standard treatment for concurrent chemo-radiotherapy in nasopharyngeal carcinoma. However, different chemotherapy schedules are presented in the literature. OBJECTIVE: We intend to compare toxicity and outcomes of high dose 3-weekly cisplatin versus low dose weekly-cisplatin and cumulative dose of cisplatin in the patients with nasopharyngeal carcinoma. METHODS: 98 patients were included in the study, between 2010 and 2018. Cumulative doses of cisplatin (≥200mg/m2 and <200mg/m2) and different chemotherapy schedules (weekly and 3-weekly) were compared in terms of toxicity and survival. Besides prognostic factors including age, gender, T category, N category and radiotherapy technique were evaluated in uni-multivariate analysis. RESULTS: Median follow-up time 41.5 months (range: 2-93 months). Five year overall survival, local relapse-free survival, regional recurrence-free survival and distant metastasis-free survival rates were; 68.9% vs. 90.3% (p=0.11); 66.2% vs. 81.6% (p=0.15); 87.3% vs. 95.7% (p=0.18); 80.1% vs. 76.1% (p=0.74) for the group treated weekly and 3 weekly, respectively. There was no statistically significant difference between groups. Five year overall survival, local relapse-free survival, regional recurrence-free survival and distant metastasis-free survival rates were; 78.2% vs. 49.2% (p=0.003); 75.8% vs. 47.9% (p=0.055); 91% vs. 87.1% (p=0.46); 80% vs. 72.2% (p=0.46) for the group treated ≥200mg/m2 and <200mg/m2 cumulative dose cisplatin. There was statistically significant difference between groups for overall survival and there was close to being statistically significant difference between groups for local relapse-free survival. Age, gender, T category, N category, chemotherapy schedules were not associated with prognosis in the uni-variety analysis. Radiotherapy technique and cumulative dose of cisplatin was associated with prognosis in uni-variate analysis (HR=0.21; 95% CI: 0.071-0.628; p=0.005 and HR=0.29; 95% CI: 0.125-0.686; p=0.003, respectively). Only cumulative dose of cisplatin was found as an independent prognostic factor in multivariate analysis (HR=0.36; 95% CI: 0.146-0.912; p=0.03). When toxicities were evaluated, such as hematological toxicity, dermatitis, mucositis, nausea and vomiting, there were no statistically significant differences between cumulative dose of cisplatin groups (<200mg/m2 and ≥200mg/m2) and chemotherapy schedules (3-weekly and weekly). But malnutrition was statistically significant higher in patients treated with 3-weekly cisplatin compared with patients treated with weekly cisplatin (p=0.001). CONCLUSION: A cisplatin dose with ≥200mg/m2 is an independent prognostic factor for overall survival. Chemotherapy schedules weekly and 3-weekly have similar outcomes and adverse effects. If patients achieve ≥200mg/m2 dose of cumulative cisplatin, weekly chemotherapy schedules may be used safely and effectively in nasopharyngeal carcinoma patients.

Protective effect of N-acetylcysteine against cisplatin ototoxicity in rats: a study with hearing tests and scanning electron microscopy.

INTRODUCTION: Ototoxicity is a health problem appearing after powerful treatments in serious health conditions. It is sometimes inevitable when treatment of the serious disease is required. Cisplatin is an antineoplastic agent which was investigated previously to reveal increased nitrogen and reactive oxygen radicals that damages hair cells, resulting in ototoxicity. N-acetylcysteine, previously shown to decrease ototoxicity caused by different agents, is known to be a powerful in vitro antioxidant. Probably N-acetylcysteine, in addition to its antioxidant effect, blocks a cascade where reactive oxygen species result in apoptosis in the cochlea. OBJECTIVES: The possible preventive effect of N-acetylcysteine in cisplatin ototoxicity was studied with auditory brain stem responses, otoacoustic emissions, and histopathological investigation of the cochlea in a scanning electron microscopy. METHODS: This study was conducted on 21 Wistar Albino rats in four groups. 1mL/kg/day three times in total intraperitoneal (i.p.) Saline (n=5), 500mg/kg/day i.p. three times in total N-acetylcysteine (n=5), i.p. 15mg/kg cisplatin alone (single dose) (n=5) and i.p. 15mg/kg cisplatin plus 500mg/kg/day N-acetylcysteine (n=6) were administered. The rats were anesthetized to study the hearing tests before and after the experiment. The rats were sacrificed to investigate the cochleas by scanning electron microscopy. RESULTS: Auditory brain stem responses and otoacoustic emissions values were attenuated in the cisplatin group. The group that received N-acetylcysteine in addition to cisplatin had better auditory brain stem responses thresholds and otoacoustic emissions. The samples obtained from the cisplatin group showed surface irregularities, degeneration areas, and total or partial severe stereocilia losses. The changes were milder in the cisplatin+N-acetylcysteine group. CONCLUSION: Cisplatin ototoxicity can be detected by auditory brain stem responses and otoacoustic emissions testing in rats. N-acetylcysteine may protect the cochlear cells from histopathological changes. We concluded that N-acetylcysteine given 4h after cisplatin injection has a potential otoprotective effect against cisplatin ototoxicity. which suggests it could be used in clinical trials.

The protective effects of whortleberry extract against cisplatin-induced ototoxicity in rats.

INTRODUCTION: Cisplatin is one of the main chemotherapeutic agents used for the treatment of many types of cancer. However, ototoxicity, one of the most serious side effects of cisplatin, restricts its usage. OBJECTIVE: We aimed to investigate the protective effects of whortleberry extract against cisplatin-induced ototoxicity by evaluating hearing and histopathological cochlear damage and by measuring the biochemical parameters affected byoxidative stress. METHODS: Forty-eight male rats were included in the study after performing Distortion Product Otoacoustic Emission test to confirm that their hearing levels were normal. The rats were randomly divided into six groups: the control group, the sham group, and, which received only whortleberry extract, only cisplatin, cisplatin+100mg whortleberry extract, cisplatin+200mg whortleberry extract, respectively. Audiologic investigation was performed by performing the Distortion Product Otoacoustic Emission test at the beginning and at the eighth day of the study. Cardiac blood samples were collected for biochemical analysis, and the rats were sacrificed to obtain cochlear histopathological specimens on the eighth day. RESULTS: The results revealed that whortleberry protects hearing against cisplatin-induced ototoxicity independent of the dose. However, high doses of whortleberry extract are needed to prevent histopathological degeneration and oxidative stress. CONCLUSION: The results obtained in this study show that whortleberry extract has a protective effect against cisplatin-induced ototoxicity.

Protective effect of gallic acid against cisplatin-induced ototoxicity in rats.

INTRODUCTION: Cisplatin is an antineoplastic agent widely used in the treatment of a variety of cancers. Ototoxicity is one of the main side-effects restricting the use of cisplatin. OBJECTIVE: The purpose of this study was to investigate the protective efficacy of gallic acid, in biochemical, functional and histopathological terms, against ototoxicity induced by cisplatin. METHODS: Twenty-eight female Sprague Dawley rats were included. Rats were randomly assigned into four groups of seven animals each. Cisplatin group received a single intraperitoneal dose of 15mg/kg cisplatin. Gallic acid group received intraperitoneal gallic acid at 100mg/kg for five consecutive days. Cisplatin+gallic acid group received intraperitoneal gallic acid at 100mg/kg for five consecutive days and a single intraperitoneal dose of 15mg/kg cisplatin at 3rd day. A control group received 1mL intraperitoneal saline solution for five consecutive days. Prior to drug administration, all rats were exposed to the distortion product otoacoustic emissions test. The test was repeated on the 6th day of the study. All rats were then sacrificed; the cochleas were removed and set aside for biochemical and histopathological analyses. RESULTS: In cisplatin group, Day 6 signal noise ratio values were significantly lower than those of the other groups. Also, malondialdehyde levels in cochlear tissues were significantly higher, superoxide dismutase and glutathione peroxidase activities were significantly lower compared to the control group. Histopathologic evaluation revealed erosion in the stria vascularis, degeneration and edema in the connective tissue layer in endothelial cells, impairment of outer hair cells and a decrease in the number of these calls. In the cisplatin+gallic acid group, this biochemical, histopathological and functional changes were reversed. CONCLUSION: In the light of our findings, we think that gallic acid may have played a protective role against cisplatin-induced ototoxicity in rats, as indicated by the distortion product otoacoustic emissions test results, biochemical findings and immunohistochemical analyses.

The effectiveness of eugenol against cisplatin-induced ototoxicity.

INTRODUCTION: Ototoxicity refers to cellular damage or function impairment developing in the inner ear in association with any therapeutic agent or chemical substance, and still represents the principal side-effect restricting the use of cisplatin. OBJECTIVE: The aim of this study was to perform a biochemical, functional and histopathological investigation of the potential protective effect of eugenol against cisplatin-induced ototoxicity. METHODS: The study was performed with 24 female Sprague Dawley rats. Distortion product otoacoustic emissions tests were performed on all animals, which were randomized into four equal groups. A single intraperitoneal dose of 15mg/kg cisplatin was administered to cisplatin group, while the eugenol group received 100mg/kg eugenol intraperitoneal for five consecutive days. 100mg/kg eugenol was administered to cisplatin+eugenol group for 5 days. On the third day, these rats were received a single dose of 15mg/kg cisplatin. The control group was given 8mL/kg/day intraperitoneal saline solution for five days. The distortion product otoacoustic emissions test was repeated 24h after the final drug administration. All animals were sacrificed, and the cochleas were subsequently used for biochemical and histopathological examinations. RESULTS: Cisplatin caused oxidative stress in the cochlea, impaired the cochlear structure and significantly reduced signal noise ratio levels. Administration of eugenol together with cisplatin reversed these effects and provided functional, biochemical and histopathological protection. CONCLUSION: The study findings represent the first indication in the literature that eugenol may protect against ototoxicity by raising levels of antioxidant enzymes and lowering those of oxidant parameters.

Mitigation of cisplatin induced nephrotoxicity by casticin in male albino rats

Abstract Cisplatin (CP) is a commonly used, powerful antineoplastic drug, having numerous side effects. Casticin (CAS) is considered as a free radical scavenger and a potent antioxidant. The present research was planned to assess the curative potential of CAS on CP persuaded renal injury in male albino rats. Twenty four male albino rats were distributed into four equal groups. Group-1 was considered as a control group. Animals of Group-2 were injected with 5mg/kg of CP intraperitoneally. Group-3 was co-treated with CAS (50mg/kg) orally and injection of CP (5mg/kg). Group-4 was treated with CAS (50mg/kg) orally throughout the experiment. CP administration substantially reduced the activities of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), glutathione S-transferase (GST), glutathione reductase (GSR), glutathione (GSH) content while increased thiobarbituric acid reactive substances (TBARS), and hydrogen peroxide (H2O2) levels. Urea, urinary creatinine, urobilinogen, urinary proteins, kidney injury molecule-1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) levels were substantially increased. In contrast, albumin and creatinine clearance was significantly reduced in CP treated group. The results demonstrated that CP significantly increased the inflammation indicators including nuclear factor kappa-B (NF-B), tumor necrosis factor- (TNF-), Interleukin-1 (IL-1), Interleukin-6 (IL-6) levels and cyclooxygenase-2 (COX-2) activity and histopathological damages. However, the administration of CAS displayed a palliative effect against CP-generated renal toxicity and recovered all parameters by bringing them to a normal level. These results revealed that the CAS is an effective compound having the curative potential to counter the CP-induced renal damage.

Resumo A cisplatina (CP) é uma droga antineoplásica poderosa, comumente usada, com vários efeitos colaterais. Casticin (CAS) é considerado um eliminador de radicais livres e um potente antioxidante. A presente pesquisa foi planejada para avaliar o potencial curativo da CAS em lesão renal induzida por PC em ratos albinos machos. Vinte e quatro ratos albinos machos foram distribuídos em quatro grupos iguais. O Grupo 1 foi considerado grupo controle. Os animais do Grupo 2 foram injetados com 5 mg / kg de PB por via intraperitoneal. O Grupo 3 foi cotratado com CAS (50 mg / kg) por via oral e injeção de CP (5 mg / kg). O Grupo 4 foi tratado com CAS (50 mg / kg) por via oral durante todo o experimento. A administração de CP reduziu substancialmente as atividades de catalase (CAT), superóxido dismutase (SOD), peroxidase (POD), glutationa S-transferase (GST), glutationa redutase (GSR), glutationa (GSH), enquanto aumentou as substâncias reativas ao ácido tiobarbitúrico (TBARS) e níveis de peróxido de hidrogênio (H2O2). Os níveis de ureia, creatinina urinária, urobilinogênio, proteínas urinárias, molécula 1 de lesão renal (KIM-1) e lipocalina associada à gelatinase de neutrófilos (NGAL) aumentaram substancialmente. Em contraste, a albumina e a depuração da creatinina foram significativamente reduzidas no grupo tratado com PC. Os resultados demonstraram que a CP aumentou significativamente os indicadores de inflamação, incluindo fator nuclear kappa-B (NF-B), fator de necrose tumoral- (TNF-), interleucina-1 (IL-1), interleucina-6 (IL-6) níveis e atividade da ciclooxigenase-2 (COX-2) e danos histopatológicos. No entanto, a administração de CAS apresentou um efeito paliativo contra a toxicidade renal gerada por CP e recuperou todos os parâmetros, trazendo-os a um nível normal. Estes resultados revelaram que o CAS é um composto eficaz com potencial curativo para combater o dano renal induzido por CP.

Mitigation of cisplatin induced nephrotoxicity by casticin in male albino rats / Mitigação da nefrotoxicidade induzida pela cisplatina pela casticina em ratos albinos machos

Cisplatin (CP) is a commonly used, powerful antineoplastic drug, having numerous side effects. Casticin (CAS) is considered as a free radical scavenger and a potent antioxidant. The present research was planned to assess the curative potential of CAS on CP persuaded renal injury in male albino rats. Twenty four male albino rats were distributed into four equal groups. Group-1 was considered as a control group. Animals of Group-2 were injected with 5mg/kg of CP intraperitoneally. Group-3 was co-treated with CAS (50mg/kg) orally and injection of CP (5mg/kg). Group-4 was treated with CAS (50mg/kg) orally throughout the experiment. CP administration substantially reduced the activities of catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), glutathione S-transferase (GST), glutathione reductase (GSR), glutathione (GSH) content while increased thiobarbituric acid reactive substances (TBARS), and hydrogen peroxide (H2O2) levels. Urea, urinary creatinine, urobilinogen, urinary proteins, kidney injury molecule-1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) levels were substantially increased. In contrast, albumin and creatinine clearance was significantly reduced in CP treated group. The results demonstrated that CP significantly increased the inflammation indicators including nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α), Interleukin-1β (IL-1β), Interleukin-6 (IL-6) levels and cyclooxygenase-2 (COX-2) activity and histopathological damages. However, the administration of CAS displayed a palliative effect against CP-generated renal toxicity and recovered all parameters by bringing them to a normal level. These results revealed that the CAS is an effective compound having the curative potential to counter the CP-induced renal damage.

A cisplatina (CP) é uma droga antineoplásica poderosa, comumente usada, com vários efeitos colaterais. Casticin (CAS) é considerado um eliminador de radicais livres e um potente antioxidante. A presente pesquisa foi planejada para avaliar o potencial curativo da CAS em lesão renal induzida por PC em ratos albinos machos. Vinte e quatro ratos albinos machos foram distribuídos em quatro grupos iguais. O Grupo 1 foi considerado grupo controle. Os animais do Grupo 2 foram injetados com 5 mg / kg de PB por via intraperitoneal. O Grupo 3 foi cotratado com CAS (50 mg / kg) por via oral e injeção de CP (5 mg / kg). O Grupo 4 foi tratado com CAS (50 mg / kg) por via oral durante todo o experimento. A administração de CP reduziu substancialmente as atividades de catalase (CAT), superóxido dismutase (SOD), peroxidase (POD), glutationa S-transferase (GST), glutationa redutase (GSR), glutationa (GSH), enquanto aumentou as substâncias reativas ao ácido tiobarbitúrico (TBARS) e níveis de peróxido de hidrogênio (H2O2). Os níveis de ureia, creatinina urinária, urobilinogênio, proteínas urinárias, molécula 1 de lesão renal (KIM-1) e lipocalina associada à gelatinase de neutrófilos (NGAL) aumentaram substancialmente. Em contraste, a albumina e a depuração da creatinina foram significativamente reduzidas no grupo tratado com PC. Os resultados demonstraram que a CP aumentou significativamente os indicadores de inflamação, incluindo fator nuclear kappa-B (NF-κB), fator de necrose tumoral-α (TNF-α), interleucina-1β (IL-1β), interleucina-6 (IL-6) níveis e atividade da ciclooxigenase-2 (COX-2) e danos histopatológicos. No entanto, a administração de CAS apresentou um efeito paliativo contra a toxicidade renal gerada por CP e recuperou todos os parâmetros, trazendo-os a um nível normal. Estes resultados revelaram que o CAS é um composto eficaz com potencial curativo para combater o dano renal induzido por CP.

The effect of genistein on cisplatin induced ototoxicity and oxidative stress / Efeito da genisteína na ototoxicidade induzida pela cisplatina e estresse oxidativo

Abstract Highlights Cisplatin is an antineoplastic agent used malignant diseases. Cisplatin ototoxicity is generally bilateral, irreversible, and progressive. Genistein is a phytoestrogen. Genistein functions as antioxidant and cell cycle inhibitor by inhibiting DNA topoisomerase. Genistein showed positive effects on ototoxicity with its antioxidant. Objective Cisplatin is an antineoplastic agent used in adults and children for the treatment of various malignant diseases. It can cause irreversible ototoxicity. Genistein is a phytoestrogen. Genistein functions as an antioxidant and cell cycle inhibitor by inhibiting the DNA topoisomerase and tyrosine protein kinase enzymes. The protective effect of genistein in preventing cisplatin-induced ototoxicity and levels of the oxidative stress was investigated. Methods 32 Sprague Dawley rats were used in 4 groups (control, cisplatin, cisplatin + genistein, genistein). Otoacoustic emission measurements of the distortion product were performed on the 1st, 2nd and 5th days of the test protocol. Serum malondialdehyde, superoxide dismutase, catalase, glutathione peroxidase, total antioxidant status, total oxidant status and oxidative stress index measurements were made. Results The hearing of the cisplatin + genistein group was found to be better than that of the cisplatin group. While the malondialdehyde, total oxidant status and oxidative stress index parameters decreased significantly in the cisplatin + genistein group compared to the cisplatin group, superoxide dismutase increased significantly (p < 0.05). Conclusion Genistein showed positive effects against ototoxicity with its antioxidant effect. Level of evidence Level 3.

Resumo DESTAQUES A cisplatina é um agente antineoplásico usado em lesões malignas. A ototoxicidade da cisplatina é geralmente bilateral, irreversível e progressiva. A genisteína é um fitoestrógeno. A genisteína funciona como antioxidante e inibidor do ciclo celular ao inibir a topoisomerase do DNA. A genisteína apresentou efeitos positivos sobre a ototoxicidade com seu efeito antioxidante. Objetivo A cisplatina é um agente antineoplásico usado em adultos e crianças para o tratamento de diversas lesões malignas. Pode causar ototoxicidade irreversível. A genisteína é um fitoestrógeno que funciona como antioxidante e inibidor do ciclo celular ao inibir as enzimas DNA topoisomerase e tirosina-quinase. O efeito protetor da genisteína na prevenção da ototoxicidade induzida pela cisplatina e os níveis de estresse oxidativo foram investigados. Método Trinta e dois ratos Sprague Dawley foram usados em 4 grupos (controle, cisplatina, cisplatina + genisteína, genisteína). As medidas das emissões otoacústicas por produto de distorção foram tomadas nos dias 1, 2 e 5 do protocolo do teste. Foram medidos os níveis séricos de malondialdeído, superóxido dismutase, catalase, glutationa peroxidase, estado antioxidante total, estado oxidante total e índice de estresse oxidativo. Resultados A audição do grupo cisplatina + genisteína foi melhor do que a do grupo cisplatina. Enquanto os parâmetros malondialdeído, estado oxidante total e índice de estresse oxidativo diminuíram significantemente no grupo cisplatina + genisteína em comparação com o grupo cisplatina, o superóxido dismutase mostrou aumento significantemente (p < 0,05). Conclusão A genisteína apresentou efeitos positivos contra a ototoxicidade com seu efeito antioxidante. Nível de evidência Nível 3.

Ototoxic effects of antineoplastic drugs: a systematic review / Efeitos ototóxicos dos medicamentos antineoplásicos: uma revisão sistemática

Abstract Introduction Platinum-based chemotherapeutics play an important role in the treatment of cancer at different levels and are the most cited ototoxic agents when scientific evidence is analyzed. Objective To present scientific evidence based on a systematic literature review, PRISMA, in order to systematize information on the ototoxic effects of using antineoplastic drugs. Methods For the selection of studies, the combination based on the Medical Subject Heading Terms (MeSH) was used. The Medline (Pubmed), LILACS, SciELO, SCOPUS, WEB OF SCIENCE and BIREME databases were used, without restriction of language, period, and location. Evaluation of the quality of the articles was carried out, which included articles with a minimum score of 6 in the modified scale of the literature. The designs of the selected studies were descriptive, cohort, and cross-sectional, which were related to the research objective. Results Three articles were included in this systematic review. The ototoxicity caused by cisplatin alone varied from 45% to 83.3%, while that caused by the use associated with carboplatin varied from 16.6% to 75%. There was a significant variation in the cumulative doses of these antineoplastic agents, both in isolated and in combination. Auditory changes, especially at high frequencies, were evident after completion of treatment. Conclusion Auditory changes after the use of platinum-based antineoplastic drugs were found, however, there was an important heterogeneity regarding the frequency of ototoxicity and the cumulative dose of the drugs used.

Resumo Introdução Os quimioterápicos à base de cisplatina desempenham papel importante no tratamento do câncer em diversos níveis e são os agentes ototóxicos mais citados quando analisadas evidências científicas. Objetivo Apresentar evidências científicas com base em revisão sistemática da literatura (PRISMA), com o intuito de sistematizar informações sobre os efeitos ototóxicos do uso de medicamentos antineoplásicos. Método Para a seleção dos estudos foi usada a combinação baseada no Medical Subject Heading Terms (MeSH). Foram usadas as bases de dados Medline (Pubmed), Lilacs, SciELO, Scopus, Web of Science e Bireme, sem restrição de idioma, período e localização. Foi feita avaliação da qualidade dos artigos, na qual se incluíam artigos com nota mínima 6 na escala modificada da literatura. Os desenhos dos estudos selecionados foram do tipo descritivo, coorte e transversal, os quais estavam relacionados com o objetivo da pesquisa. Resultados Três artigos foram admitidos para esta revisão sistemática. A ototoxicidade causada pela cisplatina isoladamente variou de 45% a 83,3%, enquanto a causada pelo uso associado com a carboplatina variou de 16,6% a 75%. Verificou-se uma variação significativa nas doses cumulativas desses antineoplásicos, tanto no uso isolado quanto em combinação. Alterações auditivas, principalmente em altas frequências, foram evidenciadas após finalização do tratamento. Conclusão Alterações auditivas após o uso de medicamentos antineoplásicos à base de platina foram constatadas, porém verificou-se uma importante heterogeneidade quanto à frequência da ototoxicidade e a dose cumulativa das drogas usadas.

Audiological profile of patients treated for childhood cancer.

OBJECTIVE: To characterize the hearing loss after cancer treatment, according to the type of treatment, with identification of predictive factors. METHODS: Two hundred patients who had cancer in childhood were prospectively evaluated. The mean age at diagnosis was 6 years, and at the audiometric assessment, 21 years. The treatment of the participants included chemotherapy without using platinum derivatives or head and neck radiotherapy in 51 patients; chemotherapy using cisplatin without radiotherapy in 64 patients; head and neck radiotherapy without cisplatin in 75 patients; and a combined treatment of head and neck radiotherapy and chemotherapy with cisplatin in ten patients. Patients underwent audiological assessment, including pure tone audiometry, speech audiometry, and immittancemetry. RESULTS: The treatment involving chemotherapy with cisplatin caused 41.9% and 47.3% hearing loss in the right and left ear, respectively, with a 11.7-fold higher risk of hearing loss in the right ear and 17.6-fold higher in the left ear versus patients not treated with cisplatin (p<0.001 and p<0.001, respectively). Children whose cancer diagnosis occurred after the age of 6 have shown an increased risk of hearing loss vs. children whose diagnosis occurred under 6 years of age (p=0.02). CONCLUSION: The auditory feature found after the cancer treatment was a symmetrical bilateral sensorineural hearing loss. Chemotherapy with cisplatin proved to be a risk factor, while head and neck radiotherapy was not critical for the occurrence of hearing loss.

A comparison of cisplatin cumulative dose and cisplatin schedule in patients treated with concurrent chemo-radiotherapy in nasopharyngeal carcinoma / Comparação da dose cumulativa de cisplatina e esquema de tratamento em pacientes com carcinoma nasofaríngeo tratados concomitantemente com quimiorradioterapia

Abstract Introduction: Three-weekly cisplatin dose is accepted for standard treatment for concurrent chemo-radiotherapy in nasopharyngeal carcinoma. However, different chemotherapy schedules are presented in the literature. Objective: We intend to compare toxicity and outcomes of high dose 3-weekly cisplatin versus low dose weekly-cisplatin and cumulative dose of cisplatin in the patients with nasopharyngeal carcinoma. Methods: 98 patients were included in the study, between 2010 and 2018. Cumulative doses of cisplatin (≥200 mg/m2 and <200 mg/m2) and different chemotherapy schedules (weekly and 3-weekly) were compared in terms of toxicity and survival. Besides prognostic factors including age, gender, T category, N category and radiotherapy technique were evaluated in uni-multivariate analysis. Results: Median follow-up time 41.5 months (range: 2-93 months). Five year overall survival, local relapse-free survival, regional recurrence-free survival and distant metastasis-free survival rates were; 68.9% vs. 90.3% (p = 0.11); 66.2% vs. 81.6% (p = 0.15); 87.3% vs. 95.7% (p = 0.18); 80.1% vs. 76.1% (p = 0.74) for the group treated weekly and 3 weekly, respectively. There was no statistically significant difference between groups. Five year overall survival, local relapse-free survival, regional recurrence-free survival and distant metastasis-free survival rates were; 78.2% vs. 49.2% (p = 0.003); 75.8% vs. 47.9% (p = 0.055); 91% vs. 87.1% (p = 0.46); 80% vs. 72.2% (p = 0.46) for the group treated ≥200 mg/m2 and <200 mg/m2 cumulative dose cisplatin. There was statistically significant difference between groups for overall survival and there was close to being statistically significant difference between groups for local relapse-free survival. Age, gender, T category, N category, chemotherapy schedules were not associated with prognosis in the uni-variety analysis. Radiotherapy technique and cumulative dose of cisplatin was associated with prognosis in uni-variate analysis (HR = 0.21; 95% CI: 0.071-0.628; p = 0.005 and HR = 0.29; 95% CI: 0.125-0.686; p = 0.003, respectively). Only cumulative dose of cisplatin was found as an independent prognostic factor in multivariate analysis (HR = 0.36; 95% CI: 0.146-0.912; p = 0.03). When toxicities were evaluated, such as hematological toxicity, dermatitis, mucositis, nausea and vomiting, there were no statistically significant differences between cumulative dose of cisplatin groups (<200 mg/m2 and ≥200 mg/m2) and chemotherapy schedules (3-weekly and weekly). But malnutrition was statistically significant higher in patients treated with 3-weekly cisplatin compared with patients treated with weekly cisplatin (p = 0.001). Conclusion: A cisplatin dose with ≥200 mg/m2 is an independent prognostic factor for overall survival. Chemotherapy schedules weekly and 3-weekly have similar outcomes and adverse effects. If patients achieve ≥200 mg/m2 dose of cumulative cisplatin, weekly chemotherapy schedules may be used safely and effectively in nasopharyngeal carcinoma patients.

Resumo Introdução: Três doses semanais de cisplatina com quimiorradioterapia concomitante são aceitas como o tratamento-padrão para carcinoma nasofaríngeo. No entanto, diferentes esquemas quimioterápicos são recomendados na literatura científica. Objetivo: Comparar a toxicidade e os resultados de 3 doses altas semanais de cisplatina versus dose baixa semanal de cisplatina em pacientes com carcinoma nasofaríngeo e verificar a dose cumulativa de cisplatina. Método: Foram incluídos 98 pacientes, entre 2010 e 2018. As doses cumulativas de cisplatina (≥ 200 mg/m2 e < 200 mg/m2) e diferentes esquemas de quimioterapia (semanal e a cada 3 semanas) foram comparadas em termos de toxicidade e sobrevida. Além disso, fatores prognósticos, inclusive idade, sexo, categoria T, categoria N e técnica de radioterapia, foram avaliados na análise uni-multivariada. Resultados: O tempo médio de seguimento foi de 41,5 meses (intervalo: 2-93 meses). Sobrevida global de cinco anos, sobrevida livre de recidiva local, sobrevida livre de recidiva regional e sobrevida livre de metástases a distância foram: 68,9% vs. 90,3% (p = 0,11); 66,2% vs. 81,6% (p = 0,15); 87,3% vs. 95,7% (p = 0,18); e 80,1% vs. 76,1% (p = 0,74) para os grupos tratados semanalmente e 3 x/semana, respectivamente. Não houve diferença estatisticamente significante entre os grupos. Taxas de sobrevida global, sobrevida livre de recidiva local, sobrevida livre de recidiva regional e sobrevida livre de metástases a distância em cinco anos foram; 78,2% vs. 49,2% (p = 0,003); 75,8% vs. 47,9% (p = 0,055); 91% vs. 87,1% (p = 0,46); 80% vs. 72,2% (p = 0,46) para o grupo tratado com ≥ 200 mg/m2 e < 200 mg/m2 de dose cumulativa de cisplatina. Houve diferença estatisticamente significante entre os grupos para sobrevida global e houve uma diferença quase estatisticamente significante entre os grupos para sobrevida livre de recidiva local. Idade, sexo, categoria T, categoria N e esquemas de quimioterapia não foram associados ao prognóstico na análise univariada. A técnica de radioterapia e dose cumulativa de cisplatina foram associadas ao prognóstico na análise univariada (HR = 0,21; IC 95%: 0,071 ± 0,628; p = 0,005 e HR = 0,29; IC 95%: 0,125 ± 0,686; p = 0,003, respectivamente). Apenas a dose cumulativa de cisplatina foi considerada um fator prognóstico independente na análise multivariada (HR = 0,36; IC 95%: 0,146 ± 0,912; p = 0,03). Quando as toxicidades foram avaliadas, como toxicidade hematológica, dermatite, mucosite, náusea e vômito, não houve diferença estatisticamente significante entre a dose cumulativa dos grupos cisplatina (< 200 mg/m2 e ≥ 200 mg/m2) e esquemas de quimioterapia (semanal e a cada 3 semanas). Entretanto, a desnutrição foi estatisticamente maior em pacientes tratados com cisplatina a cada 3 semanas em comparação com pacientes tratados com cisplatina semanalmente (p = 0,001). Conclusão: Uma dose de cisplatina ≥ 200 mg/m2 é fator prognóstico independente para sobrevida global. Os esquemas de quimioterapia semanais e a cada 3 semanas têm resultados e efeitos adversos semelhantes. Se os pacientes atingirem uma dose cumulativa ≥ 200 mg/m2 de cisplatina, os esquemas semanais de quimioterapia podem ser usados com segurança e eficácia em pacientes com carcinoma nasofaríngeo.

Use of scanning electron microscopy in the cochlea of guinea pigs / Microscopia eletrônica de varredura em cócleas de cobaias

Abstract Introduction: The use of electron microscopy in the study of the inner ear has allowed us to observe minute details of the hair cells, especially in ototoxicity studies; however, the preparation of this material is a difficult and delicate task. In an attempt to simplify the handling of these materials, two agents, toluidine blue and ethylenediamine tetra-acetic acid were tested, in addition to the elimination of osmium tetroxide during the preparation of albino guinea pig cochleae. We also tested the applicability of these methodologies in an ototoxicity protocol. Objective: To verify the quality of the images obtained with and without the use of ethylenediamine tetra-acetic acid, toluidine blue and osmium tetroxide in the preparation of cochleae of albino guinea pigs for the scanning electron microscopy. Methods: Three groups of cochleae were used. In Group 1, 10 cochleae were prepared with the usual methodology, dissecting the optical capsule without decalcification and using osmium tetroxide as a post-fixative agent. In Group 2, we prepared 10 cochleae decalcified with ethylenediamine tetra-acetic acid, injecting toluidine blue in the endolymphatic space to facilitate the identification of the organ of Corti. In Group 3, we used 4 cochleae of guinea pigs that received 3 doses of cisplatin (7.5 mg/kg, D1-D5-D6), two prepared according to the methodology used in Group 1 and two with that used in Group 2. Scanning electron microscopy images were obtained from the organ of Corti region of the basal turn of each cochlea. Results: The organ of Corti was more easily identified with the use of toluidine blue. The dissection of the cochlea was more accurate in the decalcified cochleae. The quality of the images and the preservation of the organ of Corti obtained with the two methodologies were similar. Conclusion: The proposed modifications resulted in images of similar quality as those observed using the traditional methodology.

Resumo Introdução: O emprego da microscopia eletrônica no estudo da orelha interna permitiu observar detalhes minuciosos das células ciliadas especialmente em estudos de ototoxicidade. Entretanto, o preparo desse material é trabalhoso e delicado. Para simplificar a manipulação desses materiais, testou-se o uso de dois agentes, azul de toluidina e ácido etilenodiamino tetra-acético, além da retirada do tetróxido de ósmio na preparação de cócleas de cobaias albinas. Testamos também a aplicabilidade dessas metodologias em um protocolo de ototoxicidade. Objetivo: Verificar a qualidade das imagens obtidas com e sem o uso de ácido etilenodiamino tetra-acético, azul de toluidina e tetróxido de ósmio na preparação de cócleas de cobaias albinas para a microscopia eletrônica de varredura. Método: Foram utilizados três grupos de cócleas. No Grupo 1 preparou-se 10 cócleas com a metodologia usual, dissecando a cápsula ótica sem descalcificac¸ão e utilizando tetróxido de ósmio como pós-fixador. No Grupo 2 preparamos 10 cócleas descalcificadas com ácido etilenodiamino tetra-acético, injetando azul de toluidina no espac¸o endolinfático para facilitar a identificação do órgão de Corti. No Grupo 3 utilizamos 4 cócleas de cobaias que receberam 3 doses de cisplatina (7,5 mg/kg, D1-D5-D6), duas preparadas com a metodologia do Grupo 1 e duas com a do Grupo 2. Foram obtidas imagens da microscopia eletrônica de varredura da região do órgão de Corti do giro basal de cada cóclea. Resultados: O órgão de Corti foi mais facilmente identificado com o azul de touidina. A dissecção da cóclea foi mais precisa nas cócleas descalcificadas A qualidade das imagens e a preservac¸ão do órgão de Corti obtidas com as duas metodologias foi similar. Conclusão: As modificações propostas resultaram em imagens de qualidade similar as observadas com o uso da metodologia tradicional.

Protective effect of N-acetylcysteine against cisplatin ototoxicity in rats: a study with hearing tests and scanning electron microscopy / Efeito protetor da N-acetilcisteína na ototoxicidade por cisplatina em ratos: um estudo com testes auditivos e microscopia eletrônica de varredura

Abstract Introduction Ototoxicity is a health problem appearing after powerful treatments in serious health conditions. It is sometimes inevitable when treatment of the serious disease is required. Cisplatin is an antineoplastic agent which was investigated previously to reveal increased nitrogen and reactive oxygen radicals that damages hair cells, resulting in ototoxicity. N-acetylcysteine, previously shown to decrease ototoxicity caused by different agents, is known to be a powerful in vitro antioxidant. Probably N-acetylcysteine, in addition to its antioxidant effect, blocks a cascade where reactive oxygen species result in apoptosis in the cochlea. Objectives The possible preventive effect of N-acetylcysteine in cisplatin ototoxicity was studied with auditory brain stem responses, otoacoustic emissions, and histopathological investigation of the cochlea in a scanning electron microscopy. Methods This study was conducted on 21 Wistar Albino rats in four groups. 1 mL/kg/day three times in total intraperitoneal (i.p.) Saline (n = 5), 500 mg/kg/day i.p. three times in total N-acetylcysteine (n = 5), i.p. 15 mg/kg cisplatin alone (single dose) (n = 5) and i.p. 15 mg/kg cisplatin plus 500 mg/kg/day N-acetylcysteine (n = 6) were administered. The rats were anesthetized to study the hearing tests before and after the experiment. The rats were sacrificed to investigate the cochleas by scanning electron microscopy. Results Auditory brain stem responses and otoacoustic emissions values were attenuated in the cisplatin group. The group that received N-acetylcysteine in addition to cisplatin had better auditory brain stem responses thresholds and otoacoustic emissions. The samples obtained from the cisplatin group showed surface irregularities, degeneration areas, and total or partial severe stereocilia losses. The changes were milder in the cisplatin + N-acetylcysteine group. Conclusion Cisplatin ototoxicity can be detected by auditory brain stem responses and otoacoustic emissions testing in rats. N-acetylcysteine may protect the cochlear cells from histopathological changes. We concluded that N-acetylcysteine given 4 h after cisplatin injection has a potential otoprotective effect against cisplatin ototoxicity. which suggests it could be used in clinical trials.

Resumo Introdução A ototoxicidade é um problema que pode ocorrer após certos tipos de tratamentos para condições graves de saúde. Às vezes é inevitável quando o tratamento da doença é necessário. A cisplatina é um agente antineoplásico cujo uso em pesquisas anteriores demonstrou aumentar os radicais livres de nitrogênio e espécies reativas de oxigênio que danificam as células ciliadas e resultam em ototoxicidade. Por outro lado, a N-acetilcisteína, que já demonstrou diminuir a ototoxicidade causada por diferentes agentes, é conhecida por ser um potente antioxidante in vitro. Provavelmente a N-acetilcisteína, além de seu efeito antioxidante, bloqueia uma cascata onde espécies reativas de oxigênio resultam em apoptose na cóclea. Objetivos Estudar o possível efeito preventivo da N-acetilcisteína na ototoxicidade por cisplatina por meio de potencial evocado auditivo de tronco encefálico, emissões otoacústicas e investigação histopatológica da cóclea por microscopia eletrônica de varredura. Método Este estudo foi realizado em 21 ratos albinos Wistar, separados em quatro grupos. Foram administrados: 1 mL/kg/dia intraperitoneal (i.p.) de solução salina (n = 5), três vezes no total; 500 mg/kg/dia i.p. de N-acetilcisteína (n = 5), três vezes no total; 15 mg/kg i.p. (dose única) somente de cisplatina (n = 5) e 15 mg/kg i.p. de cisplatina e 500 mg/kg/dia i.p. de N-acetilcisteína (n = 6). Os ratos foram anestesiados para estudo dos testes auditivos antes e depois do experimento. Os ratos foram sacrificados para investigação da cóclea por microscopia eletrônica de varredura. Resultados Os potenciais evocados auditivos de tronco encefálico e os valores das emissões otoacústicas estavam atenuados no grupo cisplatina. O grupo que recebeu N-acetilcisteína além da cisplatina apresentou melhores limiares de respostas auditivas do tronco encefálico e emissões otoacústicas. As amostras obtidas do grupo cisplatina apresentaram irregularidades de superfície, áreas de degeneração, com perdas graves totais ou parciais de estereocílios. As alterações foram mais leves no grupo cisplatina + N-acetilcisteína. Conclusão A ototoxicidade por cisplatina pode ser detectada por meio de potenciais evocados auditivos de tronco encefálico e pelo teste de emissões otoacústicas em ratos. A N-acetilcisteína pode proteger as células cocleares contra alterações histopatológicas. Concluímos que a N-acetilcisteína administrada 4 horas após a injeção de cisplatina tem potencial efeito otoprotetor contra a ototoxicidade por cisplatina e pode ser utilizada em ensaios clínicos.

The protective effects of whortleberry extract against cisplatin-induced ototoxicity in rats / Efeitos protetores do extrato de uva-do-monte contra a ototoxicidade induzida por cisplatina em ratos

Abstract Introduction: Cisplatin is one of the main chemotherapeutic agents used for the treatment of many types of cancer. However, ototoxicity, one of the most serious side effects of cisplatin, restricts its usage. Objective: We aimed to investigate the protective effects of whortleberry extract against cisplatin-induced ototoxicity by evaluating hearing and histopathological cochlear damage and by measuring the biochemical parameters affected byoxidative stress. Methods: Forty-eight male rats were included in the study after performing Distortion Product Otoacoustic Emission test to confirm that their hearing levels were normal. The rats were randomly divided into six groups: the control group, the sham group, and, which received only whortleberry extract, only cisplatin, cisplatin + 100 mg whortleberry extract, cisplatin + 200 mg whortleberry extract, respectively. Audiologic investigation was performed by performing the Distortion Product Otoacoustic Emission test at the beginning and at the eighth day of the study. Cardiac blood samples were collected for biochemical analysis, and the rats were sacrificed to obtain cochlear histopathological specimens on the eighth day. Results: The results revealed that whortleberry protects hearing against cisplatin-induced ototoxicity independent of the dose. However, high doses of whortleberry extract are needed to prevent histopathological degeneration and oxidative stress. Conclusion: The results obtained in this study show that whortleberry extract has a protective effect against cisplatin-induced ototoxicity.

Resumo Introdução: A cisplatina é um dos principais agentes quimioterápicos utilizados para o tratamento de muitos tipos de câncer. No entanto, a ototoxicidade, um dos efeitos colaterais mais graves da cisplatina, restringe seu uso. Objetivo: Nosso objetivo foi investigar os efeitos protetores do extrato de uva-do-monte contra a ototoxicidade induzida por cisplatina, avaliar o dano auditivo e histopatológico coclear e medir os parâmetros bioquímicos afetados pelo estresse oxidativo. Método: Foram incluídos no estudo 48 ratos machos após teste de emissão otoacústica evocada por produto de distorção para confirmar que seus níveis de audição eram normais. Os ratos foram divididos aleatoriamente em seis grupos: o grupo controle, o grupo simulado, o que recebeu apenas extrato de uva-do-monte, o que recebeu apenas cisplatina, o que recebeu cisplatina + 100 mg de extrato de uva-do-monte e o que recebeu cisplatina + 200 mg de extrato de uva-do-monte, respectivamente. A investigação audiológica foi feita através do teste de emissão otoacústica de produto de distorção no início e no oitavo dia do estudo. As amostras de sangue cardíaco foram coletadas para análise bioquímica e os ratos foram sacrificados para obtenção de espécimes histopatológicos cocleares no oitavo dia. Resultados: Os resultados revelaram que o extrato de uva-do-monte protege a audição contra a ototoxicidade induzida por cisplatina, independentemente da dose. No entanto, são necessárias doses elevadas do extrato para evitar a degeneração histopatológica e o estresse oxidativo. Conclusão: Os resultados obtidos neste estudo mostram que o extrato de uva-do-monte tem um efeito protetor contra a ototoxicidade induzida por cisplatina.

Estudo da encapsulação de fármacos antineoplásicos em sistemas nanoestruturados: Caracterização estrutural e efeito sinérgico de fármacos / Study of the encapsulation of antineoplastic drugs in nanostructured systems: Structured characterization and synergistic effect of drugs

Dentro da área da nanotecnologia, o sistema drug delivery vem sendo amplamente utilizado, cujo objetivo é proporcionar uma maior eficácia dos ativos farmacêuticos, podendo envolver desde uma distribuição mais seletiva dentro do organismo até a taxa que as moléculas serão liberadas e/ou a atenuação dos efeitos adversos provocados. Para isso, os ativos são encapsulados em nanoestruturas, podendo estas serem de natureza sintética ou natural. Dentre os nanocarreadores promissores encontram-se os cubossomos, que são nanoestruturas complexas capazes de encapsular ativos tanto hidrofílicos quanto hidrofóbicos. O objetivo deste projeto foi estudar a encapsulação de fármacos antineoplásicos em sistemas drug delivery contra linhagens celulares, investigando também as alterações estruturais sofridas pelos cubossomos e os efeitos sinérgicos dos fármacos, sendo eles: a doxorrubicina, a cisplatina, a vemurafenibe e a curcumina. As metodologias empregadas para elucidar o efeito das combinações dos fármacos, a estruturação da nanopartícula e sua citotoxicidade foram: os estudos de viabilidade celular pós-exposição, espalhamento dinâmico de luz, potencial zeta, análise de rastreamento de nanopartículas, espalhamento de raios-x a baixos ângulos, criomicroscopia eletrônica de transmissão, eficiência de encapsulação e ensaio de liberação. Inicialmente os fármacos foram testados isoladamente e em duplas, sendo utilizadas cinco linhagens celulares, afim de se promover um delineamento aos ensaios futuros. A partir destes resultados, foi-se optado por manter duas linhagens celulares, a HeLa, como representante de tecidos tumorais, e a HaCat, modelo de tecido saudável, devido a menor resistência apresentada por elas. Em relação as combinações entre as drogas, pode-se observar que todas as duplas formadas apresentaram resultados sinérgicos na linhagem tumoral, sendo mantida para os testes seguintes a combinação curcumina e vemurafenibe. Os cubossomos foram sintetizados eficientemente, sendo produzidos na ausência de fármacos bem como contendo curcumina e vemurafenibe. As nanopartículas apresentaram uma variação de diâmetro entre 189 ± 3 nm e 224 ± 2 nm, sendo o PDI entre 0,08 e 0,25. A conformação do cubossomo foi confirmada através da criomicroscopia eletrônica de transmissão e pelo espalhamento de raios-x a baixos ângulos, onde foi determinada uma estruturação característica de Pn3m. Para a eficiência de encapsulação os valores variaram entre 79% de encapsulação para a curcumina e 72% para a vemurafenibe, quando utilizadas isoladamente. No caso da encapsulação em dupla, os valores se converteram para 63% e 53% para a curcumina e vemurafenibe, respectivamente. A liberação das drogas do interior da nanopartícula oscilou entre 1500, 480 e 420 minutos para os cubossomos de curcumina, vemurafenibe e curcumina + vemunafenibe, respectivamente. Os testes de citotoxicidade demonstraram que as concentrações de 0,01 e 0,03 mg/mL foram capazes de promover uma viabilidade acima de 70%, porém, utilizando estas proporções não foi possível observar resultados significativos. Por fim, o sistema se mostrou estável e homogêneo, sendo capaz de promover a encapsulação dos fármacos tanto singularmente quanto em dupla e, apesar da quantidade de fármacos não ter sido suficiente para ocasionar alterações ao sistema celular, a execução deste trabalho abre portas para que novos estudos sejam realizados, podendo-se testar diferentes ativos bem como alterando a composição da nanopartícula afim de se reduzir a citotoxicidade

Within the area of nanotechnology, the drug delivery system has been widely used, whose objective is to provide greater effectiveness of pharmaceutical active ingredients, which may range from a more selective distribution within the organism to the rate at which the molecules will be released and/or the attenuation of adverse effects caused. To achieve this, the active ingredients are encapsulated in nanostructures, which may be synthetic or natural in nature. Among the promising nanocarriers are cubosomes, which are complex nanostructures capable of encapsulating both hydrophilic and hydrophobic active ingredients. The objective of this project was to study the encapsulation of antineoplastic drugs in drug delivery systems against cell lines, also investigating the structural changes undergone by the cubosomes and the synergistic effects ofthe drugs, namely: doxorubicin, cisplatin, vemurafenib and curcumin. The methodologies used to elucidate the effect of drug combinations, the structuring of the nanoparticle and its cytotoxicity were: post-exposure cell viability studies, dynamic light scattering, zeta potential, nanoparticle tracking analysis, small angle x-rays scattering, transmission electron cryomicroscopy, encapsulation efficiency and release assay. Initially, the drugs were tested alone and in pairs, using five cell lines, in order to promote a design for future trials. Based on these results, it was decided to maintain two cell lines, HeLa, as a representative oftumor tissues, and HaCat, a model ofhealthy tissue, due to their lower resistance. Regarding the combinations between the drugs, it can be observed that all the pairs formed presented synergistic results in the tumor lineage, with the combination of curcumin and vemurafenib being maintained for the following tests. Cubosomes were efficiently synthesized, being produced in the absence of drugs as well as containing curcumin and vemurafenib. The nanoparticles varied in diameter between 189 ± 3 nm and 224 ± 2 nm, with the PDI being between 0.08 and 0.25. The conformation ofthe cubosome was confirmed through transmission electron cryomicroscopy and small angle x-rays scattering, where a characteristic structure of Pn3m was determined. For encapsulation efficiency, values varied between 79% encapsulation for curcumin and 72% for vemurafenib, when used alone. ln the case of double encapsulation, the values converted to 63% and 53% for curcumin and vemurafenib, respectively. The release of drugs from the interior of the nanoparticle ranged between 1500, 480 and 420 minutes for the curcumin, vemurafenib and cubosomes with curcumin + vemunafenib, respectively. Cytotoxicity tests demonstrated that concentrations of 0.01 and 0.03 mg/mL were capable of promoting viability above 70%, however, using these proportions it was not possible to observe significant results. Finally, the system proved to be stable and homogeneous, being able to promote the encapsulation of drugs both singly and in pairs and, although the quantity of drugs was not enough to cause changes to the cellular system, the execution of this work opens doors for new studies are carried out, with the possibility oftesting different active ingredients as well as changing the composition of the nanoparticle in order to reduce cytotoxicity

Protective effect of gallic acid against cisplatin-induced ototoxicity in rats / Efeito protetor do ácido gálico contra a ototoxicidade induzida por cisplatina em ratos

Abstract Introduction: Cisplatin is an antineoplastic agent widely used in the treatment of a variety of cancers. Ototoxicity is one of the main side-effects restricting the use of cisplatin. Objective: The purpose of this study was to investigate the protective efficacy of gallic acid, in biochemical, functional and histopathological terms, against ototoxicity induced by cisplatin. Methods: Twenty-eight female Sprague Dawley rats were included. Rats were randomly assigned into four groups of seven animals each. Cisplatin group received a single intraperitoneal dose of 15 mg/kg cisplatin. Gallic acid group received intraperitoneal gallic acid at 100 mg/kg for five consecutive days. Cisplatin + gallic acid group received intraperitoneal gallic acid at 100 mg/kg for five consecutive days and a single intraperitoneal dose of 15 mg/kg cisplatin at 3rd day. A control group received 1 mL intraperitoneal saline solution for five consecutive days. Prior to drug administration, all rats were exposed to the distortion product otoacoustic emissions test. The test was repeated on the 6th day of the study. All rats were then sacrificed; the cochleas were removed and set aside for biochemical and histopathological analyses. Results: In cisplatin group, Day 6 signal noise ratio values were significantly lower than those of the other groups. Also, malondialdehyde levels in cochlear tissues were significantly higher, superoxide dismutase and glutathione peroxidase activities were significantly lower compared to the control group. Histopathologic evaluation revealed erosion in the stria vascularis, degeneration and edema in the connective tissue layer in endothelial cells, impairment of outer hair cells and a decrease in the number of these calls. In the cisplatin + gallic acid group, this biochemical, histopathological and functional changes were reversed. Conclusion: In the light of our findings, we think that gallic acid may have played a protective role against cisplatin-induced ototoxicity in rats, as indicated by the distortion product otoacoustic emissions test results, biochemical findings and immunohistochemical analyses.

Resumo Introdução: A cisplatina é um agente antineoplásico amplamente usado no tratamento de vários tipos de câncer. A ototoxicidade é um dos principais efeitos colaterais que restringem o uso da cisplatina. Objetivo: O objetivo deste estudo foi investigar a eficácia protetora do ácido gálico, em termos bioquímicos, funcionais e histopatológicos, contra a ototoxicidade induzida por cisplatina. Método: Vinte e oito ratas Sprague-Dawley foram incluídas. As ratas foram distribuídas aleatoriamente em quatro grupos de sete animais cada. O grupo cisplatina recebeu uma única dose intraperitoneal de 15 mg/kg de cisplatina. O grupo ácido gálico recebeu ácido gálico via intraperitoneal a uma dose de 100 mg/kg durante cinco dias consecutivos. O grupo cisplatina + ácido gálico recebeu ácido gálico via intraperitoneal a uma dose de 100 mg/kg durante cinco dias consecutivos e uma única dose intraperitoneal de 15 mg/kg de cisplatina no terceiro dia. O grupo controle recebeu 1 mL de solução salina via intraperitoneal por cinco dias consecutivos. Antes da administração do fármaco, todos os ratos foram expostos ao teste de emissões otoacústicas - produto de distorção. O teste foi repetido no sexto dia do estudo. Todos os ratos foram então sacrificados; as cócleas foram removidas e reservadas para análises bioquímicas e histopatológicas. Resultados: No grupo cisplatina, os valores da relação sinal-ruído do dia 6 foram significativamente mais baixos aos dos outros grupos. Além disso, os níveis de malondialdeído nos tecidos cocleares foram significativamente mais altos, e as atividades de superóxido dismutase e glutatione peroxidase foram significativamente mais baixas em comparação com o grupo controle. A avaliação histopatológica revelou erosão na estria vascular, degeneração e edema na camada de tecido conjuntivo em células endoteliais, comprometimento das células ciliadas externas e diminuição do número dessas células. No grupo cisplatina + ácido gálico, estas alterações bioquímicas, histopatológicas e funcionais foram revertidas. Conclusão: Tendo em vista os nossos achados, consideramos que o ácido gálico pode ter desempenhado um papel protetor contra a ototoxicidade induzida por cisplatina em ratas, conforme indicado pelos resultados do teste emissões otoacústicas - produto de distorção, achados bioquímicos e análises imuno-histoquímicas.

The effectiveness of eugenol against cisplatin-induced ototoxicity / A eficácia do eugenol contra a ototoxicidade induzida pela cisplatina

Abstract Introduction: Ototoxicity refers to cellular damage or function impairment developing in the inner ear in association with any therapeutic agent or chemical substance, and still represents the principal side-effect restricting the use of cisplatin. Objective: The aim of this study was to perform a biochemical, functional and histopathological investigation of the potential protective effect of eugenol against cisplatin-induced ototoxicity. Methods: The study was performed with 24 female Sprague Dawley rats. Distortion product otoacoustic emissions tests were performed on all animals, which were randomized into four equal groups. A single intraperitoneal dose of 15 mg/kg cisplatin was administered to cisplatin group, while the eugenol group received 100 mg/kg eugenol intraperitoneal for five consecutive days. 100 mg/kg eugenol was administered to cisplatin + eugenol group for 5 days. On the third day, these rats were received a single dose of 15 mg/kg cisplatin. The control group was given 8 mL/kg/day intraperitoneal saline solution for five days. The distortion product otoacoustic emissions test was repeated 24 h after the final drug administration. All animals were sacrificed, and the cochleas were subsequently used for biochemical and histopathological examinations. Results: Cisplatin caused oxidative stress in the cochlea, impaired the cochlear structure and significantly reduced signal noise ratio levels. Administration of eugenol together with cisplatin reversed these effects and provided functional, biochemical and histopathological protection. Conclusion: The study findings represent the first indication in the literature that eugenol may protect against ototoxicity by raising levels of antioxidant enzymes and lowering those of oxidant parameters.

Resumo Introdução: A ototoxicidade refere-se ao dano celular ou comprometimento da função da orelha interna associado a qualquer agente terapêutico ou substância química e ainda representa o principal efeito colateral que restringe o uso da cisplatina. Objetivo: O objetivo deste estudo foi realizar uma investigação bioquímica, funcional e histopatológica do potencial efeito protetor do eugenol contra a ototoxicidade induzida pela cisplatina. Método: O estudo foi realizado com 24 ratos fêmeas Sprague Dawley. Testes de emissões otoacústicas por produto de distorção foram realizados em todos os animais, os quais foram randomizados em quatro grupos iguais. Uma única dose intraperitoneal de 15 mg/kg de cisplatina foi administrada ao grupo cisplatina, enquanto o grupo eugenol recebeu 100 mg/kg de eugenol intraperitoneal por cinco dias consecutivos. Foram administrados 100 mg/kg de eugenol ao grupo cisplatina + eugenol durante 5 dias. No terceiro dia, estes ratos receberam uma dose única de 15 mg/kg de cisplatina. O grupo controle recebeu 8 mL/kg/dia de solução salina intraperitoneal por cinco dias. O teste de emissões otoacústicas por produto de distorção foi repetido 24 horas após a administração final do medicamento. Todos os animais foram sacrificados e as cócleas foram posteriormente utilizadas para exames bioquímicos e histopatológicos. Resultados: A cisplatina causou estresse oxidativo na cóclea, prejudicou a estrutura coclear e reduziu significativamente os níveis da relação sinal/ruído. A administração de eugenol juntamente com a cisplatina reverteu esses efeitos e forneceu proteção funcional, bioquímica e histopatológica. Conclusão: Os achados do estudo representam a primeira indicação na literatura de que o eugenol pode proteger contra a ototoxicidade, eleva os níveis de enzimas antioxidantes e diminui os níveis dos parâmetros oxidantes.

Audiological profile of patients treated for childhood cancer / Perfil audiológico de pacientes tratados de câncer na infância

Abstract Objective: To characterize the hearing loss after cancer treatment, according to the type of treatment, with identification of predictive factors. Methods: Two hundred patients who had cancer in childhood were prospectively evaluated. The mean age at diagnosis was 6 years, and at the audiometric assessment, 21 years. The treatment of the participants included chemotherapy without using platinum derivatives or head and neck radiotherapy in 51 patients; chemotherapy using cisplatin without radiotherapy in 64 patients; head and neck radiotherapy without cisplatin in 75 patients; and a combined treatment of head and neck radiotherapy and chemotherapy with cisplatin in ten patients. Patients underwent audiological assessment, including pure tone audiometry, speech audiometry, and immittancemetry. Results: The treatment involving chemotherapy with cisplatin caused 41.9% and 47.3% hearing loss in the right and left ear, respectively, with a 11.7-fold higher risk of hearing loss in the right ear and 17.6-fold higher in the left ear versus patients not treated with cisplatin (p < 0.001 and p < 0.001, respectively). Children whose cancer diagnosis occurred after the age of 6 have shown an increased risk of hearing loss vs. children whose diagnosis occurred under 6 years of age (p = 0.02). Conclusion: The auditory feature found after the cancer treatment was a symmetrical bilateral sensorineural hearing loss. Chemotherapy with cisplatin proved to be a risk factor, while head and neck radiotherapy was not critical for the occurrence of hearing loss.

Resumo Objetivo: Caracterizar as alterações auditivas após o tratamento do câncer, segundo o tipo de tratamento identificando os fatores preditivos. Método: Foram avaliados prospectivamente duzentos pacientes que tiveram cancer na infância. A idade média ao diagnóstico foi de 6 anos e à avaliação audiométrica de 21 anos de idade. O tratamento incluiu quimioterapia sem uso de derivados de platina ou radioterapia em cabeça e pescoço em 51 pacientes; quimioterapia com uso de cisplatina sem radioterapia em 64 pacientes; radioterapia em cabeça e pescoço sem cisplatina em 75 pacientes; e 10 pacientes receberam o tratamento combinado de radioterapia em cabeça e pescoço e quimioterapia com cisplatina. Os pacientes foram submetidos à avaliação audiológica incluindo audiometria tonal, audiometria vocal e imitanciometria. Resultados: O tratamento envolvendo quimioterapia com cisplatina levou a 41,9% e 47,3% de perda auditiva na orelha direita e esquerda, respectivamente, apresentando risco 11,7 vezes maior de desenvolver perda auditiva na orelha direita e 17,6 vezes na orelha esquerda do que aqueles que não receberam cisplatina (p < 0,001 e p < 0,001; respectivamente). Crianças cujo diagnóstico do câncer ocorreu após os 6 anos de idade mostraram maior risco de apresentar perda auditiva do que crianças menores do que 6 anos de idade (p = 0,02). Conclusão: A característica audiológica encontrada após tratamento oncológico foi perda auditiva sensorioneural bilateral simétrica. A quimioterapia com cisplatina mostrou ser fator de risco, enquanto a radioterapia em cabeça e pescoço não foi determinante para aquisição da perda auditiva.