Background/Aim: Cisplatin is a highly effective chemotherapeutic agent that is used to treat solid tumors; however, its severe side effects remain a limitation. In particular, the high incidence of cisplatin-induced ototoxicity has attracted interest. Melatonin has been shown to decrease the toxic effects of cisplatin due to its antioxidant activity, and could increase the efficacy of cancer chemotherapy. The aim of this study was to determine the effect of melatonin against ototoxicity in rats treated with cisplatin. Materials and Methods: Rats were randomly divided into four groups (saline, melatonin, cisplatin+saline, and melatonin+cisplatin). Distortion-product otoacoustic emission (DPOAE) measurements were carried out on days 1 and 8. Results: There was a decrease in DPOAE amplitudes in the animals that received cisplatin (10 mg/kg); however, the group treated with cisplatin+melatonin presented DPOAE amplitudes comparable to those of the control groups. Conclusion: Melatonin can be used as an adjuvant tumor treatment due to its ability to decrease cisplatin-induced ototoxicity.Cancer is currently a leading cause of death in both economically developed and less developed countries (1). Moreover, the global trend toward a shift in lifestyle habits that are known to increase the risk of cancer in less economically developed countries, comprising 82% of the world's population, is expected to lead to an increase in the number of new cancer cases in the next few years along with population growth and aging (1).Cancer chemotherapy was introduced in the 1940s when nitrogen mustard was first used in clinical practice. In 1969, Rosenberg et al. (2) first demonstrated the cytotoxic effect of cisplatin, and a new class of antitumor agents emerged (2). Although additional platinum analogues are clinically applied, cisplatin is still considered the most useful of these agents based on its versatility, long research history, and supportive literature (3). Indeed, cisplatin remains a highly effective chemotherapeutic agent that is widely used to treat solid tumors, including tumors of the ovary, testis, bladder, lung, and head and neck (4-6). In particular, cisplatin is one of the most effective chemotherapeutic agents for pediatric cancer patients, with an average cure rate of 85% (7, 8).The mechanism of cisplatin's antitumor activity essentially involves the binding of the drug to DNA and non-DNA targets. The damage induced by the binding of cisplatin to DNA inhibits DNA replication mechanisms, leading to cell death through apoptosis and necrosis of tumor cells (9).In clinical practice, the dose of cisplatin may be limited owing to its toxic side-effects such as nephrotoxicity, genotoxicity, neurotoxicity, and ototoxicity, often leading to a worse prognosis. Moreover, cancer patients, especially children, have a higher incidence of development of secondary tumors after cisplatin-based treatments, particularly in the proliferative organs. This is due to the genotoxic effects of the drug, which can affect all types of cell...

IntroductionAge-related hearing loss (ARHL) is a consequence of aging of the auditory system. The best known mechanism of cell death in ARHL is apoptosis due to increased production of reactive oxygen species. In this context, it is hypothesized that melatonin, owing to its high antioxidant potential and its action in the mitochondria, helps prevent or delay outer hair cell dysfunction (HCD). AimsTo evaluate the effect of melatonin on the prevention of HCD dysfunction in the ARHL process in a susceptible murine C57BL/6J model. MethodC57BL/6J animals were divided into two groups: control (CG) and melatonin (MG). The CG received a saline and ethanol solution and the MG, melatonin (10 mg/kg/day). The solutions were offered daily (50 μl) orally over a 10-month period. Distortion Product Otoacoustic Emissions (DPOAE) measurements were conducted once a month. OPEN ACCESS Citation: Serra LSM, Araújo JGd, Vieira ALS, Silva EMd, Andrade RRd, Kückelhaus SAS, et al. (2020) Role of melatonin in prevention of age-related hearing loss. PLoS ONE 15(2): e0228943. https://

New developments on biomaterials are important in surgery. The behavior of a new membrane produced from sugarcane will be evaluated in the middle ear of rats.Aim: This study analyzed the results from the interaction of the sugarcane-base biopolymer membrane in the middle ear of a rat. Materials and Methods:We ran an experimental, prospective, paired study with 24 Wistar rats. The sugarcane-base polymer membrane was inoculated in the right ear; and an autologous fascia in the left ear. The rats were divided in 3 groups of 8, and slaughtered at 4, 8 and 12 weeks after surgery. Histological analyses were performed on the rats' middle ear mucosa and their tympanic membranes. Results:There was an inflammatory reaction on the experimental group and middle ear subacute exudate in 50%of the cases; 30% chronic exudate; and 20% was normal. In the control group there was only one case of exudate. The inflammation was initially described as intense, but it decreased over time. Myringosclerosis was observed in both groups. The sugarcane biopolymer membrane was absorbed later when compared with fascia. Conclusion:The sugarcane biopolymer membrane induced an inflammatory reaction in the middle ear which decreased over time, and mild fibrosis. Future studies can indicate its use in otolaryngology. Braz J Otorhinolaryngol. 2011;77(1):44-50. BJORL ORIGINAL ARTICLE

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Cisplatin, one of the most effective and potent anticancer drugs, is used in the treatment of a wide variety of both pediatric and adult malignancies. However, the chemotherapeutic use of cisplatin is limited by its serious side effects, such as nephrotoxicity and ototoxicity. Ototoxicity produced by cisplatin is usually persistent, depending on the age of the patient, the cumulative number of doses, the number of chemotherapy cycles, the history of noise exposure, and deteriorating renal function. The mechanism of the ototoxicity caused by cisplatin is based on the generation of reactive oxygen species, which interfere with the antioxidant protection of the organ of Corti. Thus, protecting the cochlea with antioxidants ameliorates ototoxicity from cisplatin. In this context, melatonin appears as a therapeutic option for preventing the ototoxic effects of cisplatin, since the research in the last decade has proven its ability to be both a direct free radical scavenger and indirect antioxidant. In this sense, some of the evidence suggesting that melatonin is efficient for combating cisplatin-induced ototoxicity is summarized and discussed in this paper.