Melatonin ameliorates cisplatin-induced neurodegeneration in medulla oblongata through the expressions of Aqp-1,-4, inflammation, and apoptosis pathway genes.

Abstract

In this study, the neuroprotective effects of melatonin (MEL) with changes in apoptosis, inflammation, and histopathological morphology were evaluated in the medulla oblongata of cisplatin (CIS) administered rats. Although the side effects of CIS are known in many tissues, its reaction on the medulla oblongata and the molecular association underlying this effect is unclear. Male wistar albino rats were separated into four groups (control, CIS, CIS+MEL, and MEL) (n = 24). CIS and CIS+MEL groups were given 4 mg/kg CIS at 4-day intervals (days 1, 5, 9, and 13) by the first day of the study. The MEL and CIS+MEL groups were given 10 mg/kg MEL daily for 13 days. At the end of the study, the medulla oblongata sections of the rats were harvested on the 14th day, and the changes in gene expressions were examined. Expression levels of inflammation markers (TNF-α and IL-6), apoptotic markers (Bax and Casp-3), and Aqp-1 and Aqp-4 were found to significantly increase with CIS administration. On microscopic examination, hemorrhage, edema, and perivascular edema were detected in the CIS applied group compared with controls. MEL treatment significantly reduced perivascular edema (p = 0.0152) and hemorrhage (p = 0.0087). Besides, there was a significant difference between the control and CIS groups regarding pyknosis and a significant increase in pyknotic neurons in the CIS treatment group (p < 0.001). This study indicates that CIS treatment significantly impaired medulla oblongata, and combined treatment with MEL ameliorates the injury in rats.