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The aim of this study was to determine the prevalence of parainfluenza 3 (PI3) virus antigen through histopathological and immunohistochemical (IHC) methods in sheep lung samples collected from Erzurum province, Türkiye. Between August and November 2017, 1462 sheep were dissected in the slaughterhouse and their lungs were examined macroscopically. In total, 100 of the lung samples with pneumonia were selected. Routine histopathological and IHC analyses of the collected lung tissues with pneumonia were performed. Pneumonia observed through macroscopical and histopathological examinations of the lung samples was classified as purulent-catarrhal bronchopneumonia (14.00%), fibrinous bronchopneumonia (23.00%), interstitial pneumonia (69.00%), granulomatous pneumonia (7.00%), verminous pneumonia (19.00%) and pulmonary adenomatosis (6.00%). Two or three types of pneumonia were observed in many of the same cases. The PI3 virus antigen positivity rate in the IHC analysis of sheep lung samples was 19.00%. In the IHC tracing, positivities were found mostly in the alveolar macrophages and cytoplasm of bronchial, bronchiolar and alveolar epithelial cells. As a result, the prevalence of PI3 virus in sheep in Erzurum province, Türkiye, was determined to be 19.00% using KLN BVB IHC method.
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BACKGROUND/AIMS: Sepsis is an uncontrolled systemic infection, withcomplex pathophysiology that may result in acute lung organ damage and cause multiple organ failure. Although much research has been conducted to illuminate sepsis's complex pathophysiology, sepsis treatment protocols are limited, and sepsis remains an important cause of mortality andmorbidity in intensive care units.Various studies have shown that idebenone (IDE) possesses strong antioxidant properties, which inhibit lipid peroxidation and protect cells from oxidative damage. The present study aimed to evaluate the protective effects of IDE against lung injury in a cecal ligation and puncture (CLP)-induced sepsis rat model. METHODS: Male albino Wistar rats were used. The animals were divided into a healthy control (no treatment), CLP, IDE control (200 mg/kg), and CLP + IDE subgroups (50 mg/kg, 100 mg/kg, and 200 mg/kg), with nine rats in each group.IDE was administered 1 h after CLP induction.To evaluate the protective effects of IDE, lung tissues were collected 16 h after sepsis for biochemical, immunohistochemical staining, and histopathological examination. RESULTS: IDE significantly ameliorated sepsis-induced disturbances in oxidative stress-related factors, with its effects increasing in accordance with the dose.IDE also abolished histopathological changes in lung tissues associated with CLP.Furthermore, interleukin 1 beta (IL-1ß)and tumor necrosis factor-alpha (TNF-α) immunopositivity markedly decreased in the septic rats following IDE treatment. CONCLUSIONS: IDE largely mitigated the inflammatory response in sepsis-induced lung injury by decreasing free radicals and preventing lipid peroxidation. The results suggest that IDE may represent a potential novel therapeutic drug for sepsis treatment.
Assuntos
Sepse , Animais , Modelos Animais de Doenças , Pulmão , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Sepse/complicações , Sepse/tratamento farmacológico , Ubiquinona/análogos & derivadosRESUMO
In recent years, studies investigating the protective effect of hydrogen-rich water (HRW) against different diseases and the toxicity of some substances have attracted increasing attention. Here, we assessed the effects of hydrogen-rich water on different nickel-induced toxic responses (reactive oxygen species (ROS), tumor necrosis factor-alpha (TNF-α), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) of stress responses, histopathological changes) and cocoon production in earthworm model. Earthworms were randomly divided into two main groups: water (W) group including control (CW: ultrapure water), 10 (10W), 200 (200W), and 500 (500W), and hydrogen-rich ultrapure water (HRW) group including control (CHRW: hydrogen-rich ultrapure water), 10 (10HRW), 200 (200HRW), and 500 (500HRW) mg of nickel chloride kg-1 soil for 14 days. We found that cocoon production was less affected by the nickel exposure of earthworms in the 500HRW group compared to the 500W group. The ROS levels in 200HRW and 500HRW groups were less than that of 200W and 500W, respectively. The epithelial degeneration, epithelial necrosis, and necrosis in muscle fibers in tissues of earthworm were less damaged in 200HRW and 500HRW groups compared to 200W and 500W, respectively. HRW groups significantly reduced the expression of 8-OHdG induced by nickel exposure and inflammatory cytokine response including TNF-α. The study showed that hydrogen-rich water could alleviate the toxic effects of nickel-induced oxidative and inflammatory damages in earthworms. The HRW treatment known for its cheap and eco-friendly properties without any negative effects on the ecosystem can be used as a green method for alleviating the toxification effects of heavy metals in contaminated soil and increasing cocoon production of earthworms.
Assuntos
Hidrogênio , Oligoquetos , Animais , Dano ao DNA , Ecossistema , Hidrogênio/farmacologia , Necrose , Níquel/toxicidade , Estresse Oxidativo , Espécies Reativas de Oxigênio , Solo , Fator de Necrose Tumoral alfa , ÁguaRESUMO
Living organisms have an innate ability to regulate the synthesis of inorganic materials, such as bones and teeth in humans. Cadmium sulfide (CdS) can be utilized as a quantum dot that functions as a unique light-emitting semiconductor nanocrystal. The increased use in CdS has led to an increased inhalation and ingestion rate of CdS by humans which requires a broader appreciation for the acute and chronic toxicity of CdS. We investigated the toxic effects of CdS on cerebellar cell cultures and rat brain. We employed a 'green synthesis' biosynthesis process to obtain biocompatible material that can be used in living organisms, such as Viridibacillus arenosi K64. Nanocrystal formation was initiated by adding CdCl2 (1â¯mM) to the cell cultures. Our in vitro results established that increased concentrations of CdS (0.1⯵g/mL) lead to decreased cell viability as assessed using 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT), total antioxidant capacity (TAC), and total oxidant status (TOS). The in vivo studies showed that exposure to CdS (1â¯mg/kg) glial fibrillary acidic protein (GFAP) and 8-hydroxy-2' -deoxyguanosine (8-OHdG) were increased. Collectively, we describe a model system that addresses the process from the synthesis to the neurotoxicity assessment for CdS both in vitro and in vivo. These data will be beneficial in establishing a more comprehensive pathway for the understanding of quantum dot-induced neurotoxicity.
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This study investigated the effects of rutin against reproductive damage caused by toxic mercury in male rats. Thirty-five Sprague Dawley rats were used. Control group was injected with saline for 7 days. The rutin-100 group received 100 mg/kg/b.w. rutin for 7 days. Mercuric chloride (HgCl2 ) group received 1.23 mg/kg/b.w. of HgCl2 for 7 days. Mercury chloride + rutin-50 group received 50 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. HgCl2 + rutin-100 group received 100 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. It was detected that HgCl2 treatment increased malondialdehyde (MDA) levels, tumour necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) expressions, necrosis and degeneration of spermatogonium, dead and abnormal sperm percentages; tubular walls thinning; and decreased antioxidant enzyme activities and sperm motility. It was determined that rutin application reduced testicular damage caused by HgCl2 . In conclusion, rutin administration may treat HgCl2 toxicity in testes.
Assuntos
Poluentes Ambientais/toxicidade , Cloreto de Mercúrio/toxicidade , Rutina/administração & dosagem , Espermatogônias/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Masculino , Modelos Animais , Necrose/induzido quimicamente , Necrose/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatogônias/patologia , Testículo/patologiaRESUMO
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.
Assuntos
Animais , Feminino , Ratos , Eugenol/uso terapêutico , Cisplatino/toxicidade , Perda Auditiva/prevenção & controle , Antineoplásicos/toxicidade , Antioxidantes/uso terapêutico , Ratos Sprague-Dawley , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Cóclea/patologia , Modelos Animais de Doenças , Perda Auditiva/induzido quimicamenteRESUMO
PURPOSE: Ovarian ischemia-reperfusion (IR) damage continues to be a serious infertility problem. The oxidative stress plays central role in the development of IR injuries. Activation of antioxidants decreases IR injuries; however, the efficacy of antioxidant agents remains controversial. Unfortunately, there has been no evidence for medicinal use of boric acid (BA) and propolis (Prop) on ovarian IR injury on rats so far. This study will provide to reveal the potential applications of the Prop and BA in ovarian IR therapy. METHODS: The Sprague-Dawley rats were randomized into five groups: I-control, II-IR, 3 h of ischemia and 3 h of reperfusion, III and IV-a signal dose of oral BA (7 mg/kg) and Prop (100 mg/kg) alone 1 h before induction of IR, V-Prop and BA together 1 h before induction of IR. SOD (superoxide dismutase), CAT (catalase), GSH (glutathione), MPO (myeloperoxidase), MDA (malondialdehyde), and IL-6 (interleukin-6) levels were quantified by ELISA and the TNF-α (tumor necrosis factor-α), 8-OHdG (8-hydroxylo-2'-deoxyguanosin) and Caspase-3 expressions were performed by immunohistochemical analyses. RESULTS: BA and Prop pretreatment significantly reduced MPO, MDA, and IL-6 levels and pathologic score in IR rats, with no effects in control group. These agents used in therapy also decreased TNF-α, 8-OHdG and Caspase-3 protein expressions increased by IR. Furthermore, BA and Prop combination showed significant ameliorative effects on ovary injury caused by IR through acting as an antioxidant, anti-inflammatory and antiapoptotic agent. CONCLUSION: BA and Prop alone and especially in combination could be developed as therapeutic agents against ovary IR injury.
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Anti-Infecciosos/uso terapêutico , Ácidos Bóricos/uso terapêutico , Ovário/efeitos dos fármacos , Própole/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Anti-Infecciosos/farmacologia , Ácidos Bóricos/farmacologia , Feminino , Ovário/patologia , Própole/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologiaRESUMO
Testicular dysfunction or damage is among the critical side effects of chemotherapeutic drugs like cisplatin. This study was mapped out to assess the possible therapeutic effect of eugenol on cisplatin-induced testicular damage. In this experimental study, a single dose of cisplatin (15 mg/kg) was given intraperitoneally. After 72 hr of cisplatin injection, rats were sacrificed and testis tissues were removed. Tissues were examined by biochemical, histopathological and immunohistochemical methods. While tissue lipid peroxidation product and apoptotic marker levels increased, antioxidant enzyme activities of testis tissue were decreased in the cisplatin group. Additionally, histopathological damage was also determined in testis tissue. Contrary to all these results, the severity of damage in the tissue was reduced histopathologically owing to eugenol treatment. The lipid peroxidation decreased and antioxidant enzyme activities increased in the eugenol treatment group. It has been determined that eugenol has a therapeutic effect on oxidative stress and apoptosis against cisplatin-induced testicular damage.
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Antineoplásicos/efeitos adversos , Antioxidantes/administração & dosagem , Cisplatino/efeitos adversos , Eugenol/administração & dosagem , Doenças Testiculares/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Cisplatino/administração & dosagem , Modelos Animais de Doenças , Humanos , Injeções Intraperitoneais , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espermatozoides/efeitos dos fármacos , Espermatozoides/patologia , Doenças Testiculares/induzido quimicamente , Doenças Testiculares/patologia , Testículo/efeitos dos fármacos , Testículo/patologia , Resultado do TratamentoRESUMO
Zingerone (ZO), one of the active components of ginger (Zingiber officinale), is a phenolic alkanone with antioxidant, antiapoptotic, and anti-inflammatory properties. Cisplatin (CP) is a widely used chemotherapeutic drug for solid tumors, but its therapeutic use is limited due to dose-dependent nephrotoxicity. In the present study, we investigated the ameliorative effect of ZO against CP-induced nephrotoxicity. Intraperitoneal administration of single-dose CP (7 mg/kg body weight) on the first day enhanced kidney lipid peroxidation and reduced antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH). CP increased serum urea and creatinine levels and disrupted histological integrity while causing a decrease aquaporin 1 (AQP1) level in the kidney tissues. CP induced inflammatory responses by elevating the levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-33 (IL-33) and nuclear factor kappa B (NF-κB), and activities of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, it also caused oxidative DNA damage and activation of apoptotic pathway by increasing of 8-hydroxy-2'-deoxyguanosine (8-OHdG), p53, cysteine aspartate-specific protease-3 (caspase-3), and Bcl-2-associated x protein (bax) while decreasing B cell lymphoma-2 (Bcl-2). However, treatment with ZO at a dose of 25 and 50 mg/kg b.wt. for 7 days significantly decreased oxidative stress, apoptosis, inflammation, and histopathological alterations while increased AQP1 levels in the kidney tissue. The results of the current study suggested that ZO as an effective natural product attenuates CP-induced nephrotoxicity.
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Antioxidantes/metabolismo , Cisplatino/toxicidade , Guaiacol/análogos & derivados , Rim/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Animais , Apoptose/efeitos dos fármacos , Autofagia , Nitrogênio da Ureia Sanguínea , Catalase/metabolismo , Dano ao DNA , Desoxiguanosina/análogos & derivados , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Guaiacol/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Rim/metabolismo , Peroxidação de Lipídeos , Masculino , NF-kappa B/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Ratos , Superóxido Dismutase/metabolismo , Testes de Toxicidade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: Mercury is a dangerous industrial and environmental pollutant which induces severe damage in diverse organs in animal and humans. The aim of this study was to investigate the protective effect of rutin (50 and 100 mg/kg body weight) against mercuric chloride (HgCl2) (1.23 mg/kg b.w.) toxicity in rats. METHODS: The experiment was carried out in male Sprague Dawley rats (n = 35) which was divided into five groups as follow: control, rutin-100, HgCl2, HgCl2 + rutin-50 and HgCl2 + rutin-100. RESULTS: The results showed that HgCl2 caused a marked increase in the malondialdehyde (MDA) level and significantly decreased antioxidant enzyme activities (p < 0.05). HgCl2 also provoked inflammatory responses by elevating the levels of tumor necrosis factor-α (TNF-α), B-cell lymphoma-3 (Bcl-3), interleukin-1ß (IL-1ß), nuclear factor kappa B (NF-κB), interleukin-33 (IL-33), and activities of mitogen-activated protein kinase 14 (MAPK 14) and myeloperoxidase (MPO) (p < 0.05). HgCl2 also prompted the apoptotic pathway by increasing the levels of Bcl-2 associated X protein (Bax) and p53, expression of terminal deoxynucleotidyl transferase dUNT nick end labeling (TUNEL) and cysteine aspartate specific protease-3 (caspase-3). HgCl2 changed histological integrity of kidney and expression of 8-hydroxy-2'-deoxyguanosine (8-OHdG) while caused a decrease in aquaporin 1 (AQP1) water channel protein level. In contrast to this, rutin significantly decreased oxidative stress, apoptosis, inflammation and histopathological alterations while increased AQP1 levels in kidney tissues (p < 0.05). CONCLUSION: The present study indicated that rutin has a nephroprotective effect due to its anti-inflammatory, antioxidant and antiapoptotic properties.
Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Aquaporina 1/metabolismo , Inflamação/metabolismo , Rim/efeitos dos fármacos , Cloreto de Mercúrio/toxicidade , Rutina/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVES: Cisplatin is employed for chemotherapeutic purposes in several types of adult and pediatric cancer. However, side-effects including nephrotoxicity, ototoxicity, gastrointestinal effects and neuropathy restrict the use of the drug due to their adverse impacts on quality of life. This study aimed to determine whether levosimendan exhibits a protective effect against cisplatin-related ototoxicity in a rat model by means of functional, biochemical and histochemical analysis. METHODS: The study was employed with 24 female Sprague Dawley rats. After distortion product otoacoustic emissions (DPOAE) tests applied to all rats, rats were randomly assigned into four groups of six animals each. A single intraperitoneal 15 mg/kg dose of cisplatin was administered to Cisplatin group. Levosimendan group received intraperitoneal levosimendan at a dose of 100 mg/kg for five consecutive days. Cisplatin + Levosimendan group received intraperitoneal levosimendan at a dose of 100 mg/kg for five consecutive days and a single intraperitoneal dose of 15 mg/kg cisplatin at 3rd day of the study. Control group received 8 mL/kg/day intraperitoneal saline solution for five consecutive days. The DPOAE 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: A significant increase in levels of Malondialdehyde (MDA) and significantly lower activities of superoxide dismutase (SOD) and Glutathione peroxidase (GPx) were observed at rats of cisplatin group. Administration of levosimendan showed significantly lower cochlear MDA levels, while SOD and GPx activities both increased significantly. The DPOAE test performed at 6th day of the study showed a significant impairment in the signal-noise ratio (SNR) levels of rats in Cisplatin group. The SNR levels of rats treated with levosimendan were significantly higher than those of cisplatin group and were similar to those of the control group. Cisplatin impaired the cochlear structure and a severe Caspase 3 and 8-hydroxy-2' -deoxyguanosine (8-OHdG) immunopositivity was observed at cochlea of the rats of cisplatin group. Administration of levosimendan protected the structure of cochlea and there was a mild Caspase 3 and 8OHdG immunopositivity. CONCLUSION: Our data demonstrate that levosimendan protects hearing against cisplatin-induced ototoxicity and obviates cellular degeneration. It also significantly reduces oxidative stress and apoptosis, probable mechanisms involved in ototoxicity.
Assuntos
Cóclea/metabolismo , Cóclea/patologia , Perda Auditiva/prevenção & controle , Inibidores da Fosfodiesterase 3/uso terapêutico , Simendana/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Animais , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Cisplatino/efeitos adversos , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Modelos Animais de Doenças , Feminino , Glutationa Peroxidase/metabolismo , Audição/efeitos dos fármacos , Perda Auditiva/induzido quimicamente , Perda Auditiva/fisiopatologia , Malondialdeído/metabolismo , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Razão Sinal-Ruído , Superóxido Dismutase/metabolismoRESUMO
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.