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This review offered a comprehensive analysis of tendon and ligament injuries, emphasizing the crucial role of tendon-derived stem cells (TDSCs) in tissue engineering as a potential solution for these challenging medical conditions. Tendon and ligament injuries, prevalent among athletes, the elderly, and laborers, often result in long-term disability and reduced quality of life due to the poor intrinsic healing capacity of these avascular structures. The formation of biomechanically inferior scar tissue and a high rate of reinjury underscore the need for innovative approaches to enhance and guide the regenerative process. This review delved into the complexities of tendon and ligament structure and function, types of injuries and their impacts, and the limitations of the natural repair process. It particularly focused on the role of TDSCs within the context of tissue engineering. TDSCs, with their ability to differentiate into tenocytes, are explored in various applications, including biocompatible scaffolds for cell tracking, co-culture systems to optimize tendon-bone healing, and graft healing techniques. The review also addressed the challenges of immunoreactivity post-transplantation, the importance of pre-treating TDSCs, and the potential of hydrogels and decellularized matrices in supporting tendon regeneration. It concluded by highlighting the essential roles of mechanical and molecular stimuli in TDSC differentiation and the current challenges in the field, paving the way for future research directions.
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Osteoarthritis (OA), characterized by chronic pain, significantly affects the quality of life of affected individuals. Key factors in OA pathogenesis include cartilage degradation and inflammation. Signal transducer and activator of transcription 3 (STAT3), a member of the STAT protein family, plays a pivotal role in mediating inflammation. STX-0119 has been verified as a small molecular compound that can specifically inhibit STAT3. However, the efficacy of STX-0119 in the treatment of OA remains to be evaluated. Therefore, the aim of this study was to explore the therapeutic effects and molecular mechanisms of STX-0119 in the treatment of OA. We found that the expression of phosphorylated STAT3 is upregulated in human OA cartilage as well as in the cartilage of a mouse model of OA. In vivo, joint injection of STX-0119 into OA mice alleviated cartilage degeneration without affecting the subchondral bone. Additionally, STX-0119 could inhibit the phosphorylation of STAT3 in the cartilage. In vitro, STX-0119 suppressed inflammatory responses in chondrocytes and promoted anabolic metabolism in an interleukin-1ß-induced chondrocyte inflammation model. Additionally, the results of transcriptome sequencing and lentiviral infection assays demonstrated that in chondrocytes, STX-0119 induces the upregulation of peroxisome proliferators-activated receptor gamma (PPARγ) expression by inhibiting STAT3 phosphorylation. Finally, in ex vivo cultures of human cartilage samples, STX-0119 was reaffirmed to inhibit cartilage degeneration via the STAT3/PPARγ signaling pathway. Together, our findings support the potential of STX-0119 for development as a therapeutic agent targeting STAT3 for the treatment of OA.
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Camundongos Endogâmicos C57BL , Osteoartrite , PPAR gama , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Animais , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Osteoartrite/metabolismo , Humanos , Camundongos , Transdução de Sinais/efeitos dos fármacos , PPAR gama/metabolismo , PPAR gama/antagonistas & inibidores , Masculino , Progressão da Doença , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Células CultivadasRESUMO
BACKGROUND: Spinal cord injury (SCI) is a devastating condition, often leading to significant disability and impairment. As crucial immune cells, macrophages play a critical role in the pathophysiology of SCI. Understanding the current state of knowledge and research trends related to macrophages in SCI is crucial for developing effective therapeutic interventions. METHODS: Using search strategies, we retrieved relevant articles from the Web of Science Core Collection (WOSCC), resulting in a robust dataset for analysis. VOSviewer, Citespace, and PRISM were employed for analysis and visualization. Various bibliometric indicators, including publication trends, citation analysis, co-authorship networks, and keyword analysis, were utilized to assess the scholarly landscape of macrophage research in SCI. RESULTS: Our findings revealed a steady increase in publications over the past 33 years, indicating a growing interest in this field. We identified Popovich Phillip G was the most influential author, Ohio State University was the most influential institution, and identification of 2 distinct macrophage subsets with divergent effects causing either neurotoxicity or regeneration in the injured mouse spinal cord was the most influential paper in this field. CONCLUSIONS: This bibliometric analysis provides a comprehensive overview of the current knowledge landscape and research trends regarding macrophages in SCI. Neuroinflammation and macrophage polarization, transplation and molecular mechanism were emerging research areas and novel directions. Our study serves as a valuable resource for researchers in spinal cord injury research and therapeutic development.
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Traumatismos da Medula Espinal , Animais , Camundongos , Humanos , Traumatismos da Medula Espinal/terapia , Autoria , Bibliometria , Instalações de Saúde , MacrófagosRESUMO
Gastric cancer (GC) remains one of the most common types of cancer worldwide and has a high mortality rate. However, tools for the early detection of gastric cancer are still lacking. Isobaric tagging for relative and absolute quantitation (iTRAQ) proteomic assays were conducted to identify and quantify the differentially expressed proteins (DEPs) in the gastric mucosal tissues of GC patients at different stages. Bioinformatics analysis was used to identify the pathways enriched among the DEPs and candidate marker proteins. The expression levels and distribution of candidate proteins were confirmed by parallel reaction monitoring (PRM) analysis. In this study, by using the iTRAQ quantitative proteomic strategy, we identified 727 and 502 DEPs that were upregulated in EGC vs. PGC and EGC vs. NGC, respectively. These DEPs were mainly involved in the innate immune response and RNA binding. PRTN3 was identified as a marker of early gastric cancer by Gene Ontology enrichment analysis. Furthermore, the PRM assay confirmed the significant overexpression of PRTN3 in EGC gastric mucosa compared to PGC and NGC mucosa. Our data demonstrated that PRTN3 in the gastric mucosa could be used as a novel biomarker to identify patients with early gastric cancer via endoscopy. SIGNIFICANCE: Gastric cancer remains one of the most common types of cancer worldwide and has a high mortality rate. Patients with progressive gastric cancer and gastroesophageal junction cancer have a poor prognosis, with a 5-year relative survival rate of 6%. Therefore, early detection and diagnosis of gastric cancer is a key step toward improving the survival rate. The present study identified PRTN3 as a marker of early gastric cancer by an iTRAQ quantitative proteomic strategy. The PRM assay confirmed the significant overexpression of PRTN3 in EGC gastric mucosa compared to PGC and NGC mucosa. This study discovered that PRTN3 in the gastric mucosa could be used as a novel biomarker to identify patients with early gastric cancer via endoscopy.
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Neoplasias Gástricas , Humanos , Biomarcadores , Mucosa Gástrica/metabolismo , Proteômica , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , MieloblastinaRESUMO
Purpose: This study was aimed to examine the global research status and current research hotspots in the field of tendon stem cells. Methods: Bibliometric methods were employed to retrieve relevant data from the Web of Science Core Collection (WOSCC) database. Additionally, Citespace, Vosviewer, SCImago, and Graphad Prism were utilized to analyze the publication status in this field, identify the current research hotspots, and present a mini-review. Results: The most active countries in this field were China and the United States. Notable authors contributing significantly to this research included Lui Pauline Po Yee, Tang Kanglai, Zhang Jianying, Yin Zi, and Chen Xiao, predominantly affiliated with institutions such as the Hong Kong Hospital Authority, Third Military Medical University, University of Pittsburgh, and Zhejiang University. The most commonly published journals in this field were Stem Cells International, Journal of Orthopedic Research, and Stem Cell Research and Therapy. Moreover, the current research hotspots primarily revolved around scaffolds, molecular mechanisms, and inflammation regulation. Conclusion: Tendon stem cells hold significant potential as seed cells for tendon tissue engineering and offer promising avenues for further research Scaffolds, molecular mechanisms and inflammation regulation are currently research hotspots in this field.
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Curcumin (CUR) is well known for its anti-inflammatory and antioxidant effects. However, the endothelial protective effect of CUR in diabetes and the underlying signaling pathway remains unclear. The goal of the current study was to provide evidence regarding the protective mechanism of CUR against the high glucose (HG)-induced damage to human umbilical vein endothelial cells (HUVECs). HG-induced HUVECs injury model was used to evaluate the protective effect and the underlying mechanism of CUR against endothelial injury. The cell viability was determined by the MTT method. The cell reactive oxygen species (ROS) were determined by using flow cytometry. The protein expression levels of Bcl-2, Bax, LC3-II/I, Beclin-1, p62, cleaved caspase-3, IκBα and NF-κB were measured by the western blotting. Results showed that CUR significantly decreased the cell apoptosis, the ROS generation and the inflammatory cytokine NF-κB activity in the HG-induced HUVECs versus the control, P<0.05. In addition, CUR significantly increased the expressions of LC3-II/I, Beclin-1, IκBα and Bax/Bcl-2 in the HG-induced HUVECs versus the control, P<0.05. Furthermore, the addition of autophagy inhibitor 3-MA impaired the autophagy, exacerbated the apoptotic death and increased the ROS and NF-κB levels in HUVECs under the high glucose condition, P<0.05. In brief, autophagy served a protective role in the HG-induced apoptosis in HUVECs and CUR alleviated apoptosis by promoting autophagy and inhibiting the ROS/NF-κB signaling pathway.
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BACKGROUND: Carvacrol is a monoterpenic phenol extracted from traditional Chinese herbs, including oregano and thyme. Currently, carvacrol has been widely studied for its therapeutic role in central nervous system diseases, liver diseases and digestive system cancer. OBJECTIVE: However, the role of carvacrol in osteosarcoma and its underlying molecular mechanism remain elusive. Here, we aimed to examine the anticancer effects of carvacrol on osteosarcoma. METHODS: The effects of carvacrol on the osteosarcoma proliferation capacity were revealed by CCK-8 and colony formation assays. Flow cytometry and Hoechst assays were used to determine the effects of carvacrol on osteosarcoma cell apoptosis. The effect of carvacrol on migration and invasion of osteosarcoma cells was determined by wound healing and transwell tests. Protein expression was evaluated by WB assays. The suppressive effects of carvacrol on osteosarcoma in vivo were examined by a xenograft animal model, immunohistochemistry and HE staining. RESULTS: We demonstrated that carvacrol treatment reduced viability and inhibited the colony formation of U2OS and 143B cells in a concentration-dependent manner. Apoptotic cell number increased after exposure to carvacrol. Meanwhile, the expression of Bax increased, and that of Bcl-2 decreased by carvacrol treatment. In addition, the MMP-9 expression and migration and invasion of 143B and U2OS cells were inhibited by carvacrol. We also found that these carvacrol-induced effects on osteosarcoma are associated with the regulation of the Wnt/ß-catenin signaling pathway. CONCLUSION: Our findings suggest that carvacrol suppresses proliferation, migration, invasion and promotes apoptosis in osteosarcoma cells, in part by regulating the Wnt/ß-catenin signaling pathway.
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Neoplasias Ósseas , Osteossarcoma , Animais , Apoptose , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cimenos , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Fenóis/farmacologia , Via de Sinalização WntRESUMO
OBJECTIVE: Available data on dichotic listening using tonal Chinese words have been limited, and conflicting results on a right-ear advantage (REA) have been reported. The current study developed a set of Mandarin CV-words based on the Bergen dichotic listening paradigm. DESIGN: The test materials consisted of two sets of stimuli. The English set, derived from the iDichotic application, consisted of six nonsense syllables with plosives conjugated to /a/. The Mandarin set had these 6 CV-syllables spoken as real words according to the Mandarin phonology. Study sample: Forty young, native Mandarin speakers were tested dichotically with both sets of test materials. Twenty participants were right-handed, and the other twenty were left-handed. Fourteen participants were randomly selected to repeat the test with the Mandarin set. RESULTS: The mean difference of correct recognition responses between two ears indicated a REA with both sets of stimuli for the right-handers, but not for left-handers. For the right-handers, performance with the Mandarin set was significantly better than performance with the English set. Dichotic listening with the Mandarin set had strong correlation between two time points, r = 0.8. CONCLUSIONS: Performance using the Mandarin set is reliable in dichotic listening; a REA is observed for the right-handers.
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Testes com Listas de Dissílabos , Percepção da Fala , Percepção Auditiva , Orelha , Lateralidade Funcional , Humanos , Proibitinas , Reconhecimento PsicológicoRESUMO
BACKGROUND: Proton pump inhibitors (PPI) and histamine 2 receptor antagonists (H2RA) have been widely used as stress ulcer prophylaxis (SUP) in critically ill patients, however, its efficacy and safety remain unclear. This study aimed to assess the effect of SUP on clinical outcomes in critically ill adults. METHODS: Literature search was conducted in PubMed, EMBASE, Web of Science, and the Cochrane database of clinical trials for randomized controlled trials (RCTs) that investigated SUP, with PPI or H2RA, versus placebo or no prophylaxis in critically ill patients from database inception through 1 June 2019. Study selection, data extraction and quality assessment were performed in duplicate. The primary outcomes were clinically important gastrointestinal (GI) bleeding and overt GI bleeding. Conventional meta-analysis with random-effects model and trial sequential analysis (TSA) were performed. RESULTS: Twenty-nine RCTs were identified, of which four RCTs were judged as low risk of bias. Overall, SUP could reduce the incident of clinically important GI bleeding [relative risk (RR) = 0.58; 95% confidence intervals (CI): 0.42-0.81] and overt GI bleeding (RR = 0.48; 95% CI: 0.36-0.63), these results were confirmed by the sub-analysis of trials with low risk of bias, TSA indicated a firm evidence on its beneficial effects on the overt GI bleeding (TSA-adjusted CI: 0.31-0.75), but lack of sufficient evidence on the clinically important GI bleeding (TSA-adjusted CI: 0.23-1.51). Among patients who received enteral nutrition (EN), SUP was associated with a decreased risk of clinically important GI bleeding (RR = 0.61; 95% CI: 0.44-0.85; TSA-adjusted CI: 0.16-2.38) and overt GI bleeding (RR = 0.64; 95% CI: 0.42-0.96; TSA-adjusted CI: 0.12-3.35), but these benefits disappeared after adjustment with TSA. Among patients who did not receive EN, SUP had only benefits in reducing the risk of overt GI bleeding (RR = 0.37; 95% CI: 0.25-0.55; TSA-adjusted CI: 0.22-0.63), but not the clinically important GI bleeding (RR = 0.27; 95% CI: 0.04-2.09). CONCLUSIONS: SUP has benefits on the overt GI bleeding in critically ill patients who did not receive EN, however, its benefits on clinically important GI bleeding still needs more evidence to confirm.
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Estado Terminal , Hemorragia Gastrointestinal/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Úlcera Péptica/prevenção & controle , Inibidores da Bomba de Prótons/uso terapêutico , Estresse Fisiológico , Hemorragia Gastrointestinal/fisiopatologia , Humanos , Úlcera Péptica/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Objective: Data with regard to the Mandarin dichotic digits test (DDT) are limited, with conflicting results reported between the Mandarin and English DDTs. The current study examined factors that might affect the performance in the Mandarin DDT. Design: The digits were arranged in 3 sets of 20 dichotic pairs; each set comprised 2, 3 or 4 digits in a pair. Study sample: Forty-one young, native Mandarin speakers with normal hearing were tested; 30 of them were right-handed and 11 left-handed. Six participants repeated the test. Results: The prevalence of ceiling effect in recognition score decreased systematically as the digit-pair length increased. At digit sets of 3-pair and 4-pair, the right-handed group showed a significant higher recognition score at right ear than left ear, while the left-handed group reversed the performance. The score difference between ears is significantly different between the right- and left-handed groups. The retest of the Mandarin DDT was reliable. Conclusions: For the right-handed group, a right-ear advantage can exist in the Mandarin DDT at a longer digit-pair length, similar to what was reported in the English DDT. Moreover, for the left-handed group, the attended right hemisphere in processing the tonal digits can result in a left-ear advantage.
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Testes com Listas de Dissílabos/estatística & dados numéricos , Reconhecimento Psicológico/fisiologia , Percepção da Fala , Adulto , Povo Asiático/psicologia , Testes com Listas de Dissílabos/métodos , Feminino , Lateralidade Funcional/fisiologia , Humanos , Idioma , Masculino , Adulto JovemRESUMO
Purpose: For Indo-European languages, "speech banana" is widely used to verify the benefits of hearing aids and cochlear implants. As a standardised "Mandarin speech banana" is not available, clinicians in China typically use a non-Mandarin speech banana. However, as Chinese is logographic and tonal, using a non-Mandarin speech banana is inappropriate. This paper was designed to develop the Mandarin speech banana according to the Mandarin phonetic properties. Method: In the first experiment, 14 participants read aloud the standard Mandarin initials and finals. For each pronounced sound, its formants were measured. The boundary of all formants formed the formant graph (intensity versus frequency). In the second experiment, 20 participants listened to a list of pre-recorded initials and finals that had been filtered with different bandwidths. The minimum bandwidth to recognise a target sound defined its location on the formant graph. Result: The Mandarin speech banana was generated with recognisable initials and finals on the formant graph. Tone affected the shape of the formant graph, especially at low frequencies. Conclusion: Clinicians can use the new M andarin speech banana to counsel patients about what sounds are inaudible to them. Speech training can be implemented based on the unheard sounds in the speech banana.
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Idioma , Acústica da Fala , Patologia da Fala e Linguagem/normas , Povo Asiático , Feminino , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: Previous studies reported a similar rate of complications, including stent migration and obstruction, between individualized stents and the standard uncovered stents in gastric outlet obstruction (GOO) caused by distal stomach cancer. The objective of this study was to evaluate the efficacy and safety of funnel stents for management of GOO caused by distal stomach cancer. METHODS: This study was designed as a multicenter, controlled, prospective, and randomized clinical trial involving 4 hospitals. The individualized stent group (44 cases) received cup and funnel covered stents, and the funnel group (44 cases) received only funnel covered stents for management of GOO caused by distal gastric cancer. RESULTS: All patients with GOO were treated with cup and funnel stents according to their assigned groups. The rate of GOO resolution was 100% in the funnel group and 97.7% in the individualized stent group. Stent obstruction caused by tumor ingrowth was observed in 1 patient in the individualized stent group, and proximal partial stent migration was observed in 1 patient in each group. Stent obstruction caused by tumor ingrowth was observed in 1 patient in the individualized stent group. There was no statistical difference in stent migration, obstruction, and survival between groups. CONCLUSION: Big funnel stents and individualized stents resulted in similar shaping effect and prevention of stent migration and obstruction, suggesting that funnel shaped stents can be used to treat cup or funnel shaped GOO caused by distal stomach cancer.
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Obstrução da Saída Gástrica/etiologia , Obstrução da Saída Gástrica/cirurgia , Stents , Neoplasias Gástricas/complicações , Idoso , Idoso de 80 Anos ou mais , Endoscopia do Sistema Digestório , Desenho de Equipamento , Humanos , Estudos ProspectivosRESUMO
Helicobacter pylori, the primary causative agent of stomach cancer, is known to affect gastric mucin expression. However, the underlying molecular mechanisms mediating this H. pylori-dependent effect remain unknown. In the present study, the effect of exogenous expression of the H. pylori virulence factor, CagA, on mucin 5AC oligomeric muscus/gel-forming (MUC5AC) expression was investigated using an in vitro model of the gastric mucosa. AGS cells were either untreated or transfected by a vector control (pCDNA3.1) or heterologous DNA, which induced CagA overexpression (pCDNA3.1-CagA). The expression and functionality of MUC5AC was analyzed using the reverse transcription-quantitative polymerase chain reaction and immunofluorescence assays. The expression of H. pylori-CagA in AGS cells was able to significantly upregulate MUC5AC expression compared to the vector control. In addition, immunofluorescence assays were able to validate increased MUC5AC expression following exogenous expression of H. pylori-CagA. The results of the present study revealed that the H. pylori-derived virulence factor CagA was able to increase the expression of MUC5AC. As this mucin constitutes an important ecological niche for H. pylori, this response may be involved in H. pylori colonization of the stomach.
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mTOR over-activation is important for human osteosarcoma (OS) tumorigenesis and progression. RES-529 is a mTORC1/2 dual inhibitor. Here, our results show that RES-529 inhibited viability, cell cycle progression and proliferation of the established (U2OS line) and primary human OS cells. RES-529 induced apoptosis activation in OS cells. It was yet non-cytotoxic to OB-6 osteoblastic cells and the primary human osteoblasts. RES-529 disrupted assembling of mTORC1 (mTOR-Raptor association) and mTORC2 (mTOR-Rictor-mLST8 association) in human OS cells, blocking mTORC1/2 activation. Significantly, RES-529 induced reactive oxygen species (ROS) production and mitochondrial depolarization in U2OS cells as well. RES-529-induced anti-OS cell activity was more potent than other known Akt-mTOR inhibitors. In vivo, RES-529 intraperitoneal injection significantly inhibited U2OS xenograft tumor growth in severe combined immunodeficiency (SCID) mice. mTORC1/2 activation in RES-529-treated tumor tissues was largely inhibited. Collectively, the mTOR inhibitor RES-529 efficiently inhibits human OS cell growth in vitro and in vivo.
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Antineoplásicos/uso terapêutico , Benzopiranos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Osteossarcoma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Antineoplásicos/farmacologia , Benzopiranos/farmacologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Camundongos SCID , Terapia de Alvo Molecular , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Inibidores de Proteínas Quinases/farmacologiaRESUMO
The ovarian hormones fluctuate during the menstrual cycle in women. Such fluctuation of sex hormones, in particular estrogen, is believed to affect the central conduction time in auditory function as well as the language lateralization in cognitive function. However, findings are inconsistent. The underlying mechanisms are also unclear. This paper examined if there was any relation between the central conduction time and the language lateralization at different times during the menstrual cycle. Twenty young women with normal menstrual cycle were tested four times (5 to 7 days apart) across the menstrual cycle. The test battery included the electrophysiological measurement of auditory evoked response in brainstem and the speech performance in dichotic listening with monosyllables as stimulus pairs. The dichotic listening task was conducted under the non-forced, forced-right and forced-left attention. The central conduction time was defined by the time elapsed between two auditory elicited responses along the auditory pathway. The language lateralization in dichotic listening was expressed in ear advantage, which was the right-ear score minus the left-ear score. The results showed that the effects of test time were significant on both the central conduction time and the ear advantage under the forced-left attention. Overall, the interaural difference in the central conduction time correlates with the ear advantage (non-forced attention) at the beginning of the menstrual cycle. The change in central conduction time between two test times correlates significantly with the change in ear advantage under the non-forced and forced-left attention. Conclusively, the central conduction time depends on the time during the menstrual cycle, which in turn may affect the performance in dichotic listening.
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Testes com Listas de Dissílabos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Ciclo Menstrual/fisiologia , Percepção Auditiva/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Fatores de Tempo , Adulto JovemRESUMO
CONCLUSION: The ovariectomy in rats does not change their auditory function. However, combining ovariectomy with Cisplatin treatment increases the risk of damaging the auditory function relative to the ototoxic effect caused by Cisplatin alone or ovariectomy alone. OBJECTIVES: The auditory benefit from estrogen depends on a number of factors that make findings among studies controversial. The present study was to examine the impact of Cisplatin, a chemotherapy drug, on the auditory function of ovariectomized rats. METHODS: Thirty-two female rats were assigned to three groups (OVX + C, OVX - C, Sham + C). The rats in the OVX + C and OVX - C groups received bilateral ovariectomy, and those in the Sham + C group received a sham surgery with intact ovaries. After 6 weeks the rats in the OVX + C and Sham + C groups were then treated with Cisplatin for 4 days, but not those in the OVX - C group (control). The auditory function was measured with DPOAE SNRs and ABR thresholds before the surgery and after the Cisplatin treatment. RESULTS: The OVX + C group had significantly decreased the DPOAE SNRs and increased the ABR thresholds relative to the Sham + C group at stimulus frequencies between 2-8 kHz, and the Sham + C group also had worse auditory function than the OVX - C group.
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Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Estrogênios/deficiência , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Perda Auditiva/induzido quimicamente , Animais , Feminino , Ovariectomia , Distribuição Aleatória , Ratos Sprague-DawleyRESUMO
OBJECTIVE: The benefits of estrogen for the auditory function of women depend on a number of factors. In this study, we aimed to examine the impact of noise trauma on the auditory function of ovariectomized rats with estrogen deficiency. MATERIALS AND METHODS: Twenty-eight young, female Sprague-Dawley rats were assigned to three groups (OVX+N, OVX-N, Sham+N). Rats in the OVX+N group and the OVX-N group underwent bilateral ovariectomy (OVX); the OVX+N group alone was also exposed to white noise (N) of 115 dB SPL for 8 hours a day over 14 days. The Sham+N group consisted of rats with intact ovaries that were exposed to the same noise. The auditory function of all rats was measured before treatment and after noise exposure by the signal-to-noise ratio (SNR) of distortion-product otoacoustic emissions (DPOAE) and the threshold of auditory-evoked brainstem response (ABR). RESULTS: The Sham+N group (intact ovaries, noise-exposed) had worse auditory function than the OVX-N group (ovariectomy, no noise). The OVX+N group had decreased SNRs of DPOAE and increased ABR thresholds relative to the Sham+N group. CONCLUSION: Noise exposure may cause greater damage to auditory function when estrogen levels are low in females.