Melatonin as a promising therapeutic intervention for restoring ovarian function in letrozole-induced polycystic ovary syndrome rats.

Polycystic ovary syndrome (PCOS) is a common hormonal disorder that affects women of reproductive age and is characterized by multiple ovarian cysts, irregular menstrual cycles, and excessive androgen hormone production. The present study aimed to investigate the therapeutic efficacy of melatonin in alleviating PCOS-induced alterations in female Wistar rats. PCOS was induced in female albino rats by administering letrozole at a dose of 1 mg/kg for 21 days. A total of 24 rats were randomly selected and divided into four groups: group I (normal control), group II (melatonin treatment), group III (letrozole treatment), and group IV (melatonin therapy for PCOS rats). Physical parameters (body and uterus weight), hormone profile (LH and FSH), and steroidogenic enzyme activities and an oral glucose test were assessed using standard methods. Histological analysis was performed using hematoxylin and eosin staining. The results demonstrated that exogenous melatonin administration significantly improved PCOS symptoms in rats, including reduced body weight gain, changes in organ weight/body weight index, blood glucose level, percentage diestrus phase, testosterone, estradiol, progesterone, and LH/FSH ratio, as well as 3ß-HSD and 17ß-HSD enzyme activity. Histopathological findings revealed well-developed follicles, decreased cystic follicles, and increased antral follicles, Graafian follicles, and corpus luteum in PCOS rats treated with melatonin. These positive outcomes suggest that exogenous melatonin may hold promise as a valuable remedy for PCOS conditions in female rats. Further research is warranted to fully elucidate the underlying mechanisms and potential clinical applications of melatonin in the context of PCOS.

Combined administration of exogenous melatonin and insulin ameliorates streptozotocin induced toxic alteration on hematological parameters in diabetic male Wistar rats.

The aim of the present was to ameliorate the protective effect of exogenous melatonin and insulin against the diabetes induced alterations in the different hematological variables. Albino rats were administrated streptozotocin at the dose of 15 mg/kg for 6 days. Total 54 rats were randomly selected for the experimental purpose and were divided into two major groups. Group-1 consisting twenty four (24) and were further sub-divided into four (4) different groups viz. group-I served as normal control, group-II served as melatonin treated, group-III served as insulin treated and group-IV served as glibenclamide treated. Group-2 consisting thirty (30) rats were given streptozotocin (STZ) injection (15 mg/kg) for 6 days. After confirmation of diabetes by measuring blood glucose level, animals having blood glucose level above 250 mg/dl) confirmed as diabetic. Thirty (30) Diabetic rats were further subdivided into following sub-groups and were given different therapeutic treatments, Viz group-I served as Diabetic control, group-II treated with melatonin, group-III treated with insulin, group-IV given treatment of melatonin and insulin and group-V were given treatment of glibenclamide respectively. Diabetic rats showed modulation in all the studied hematological variables. Diabetic rats displayed significant decline in RBCs count, HB level and its associated indices (HCT, RDW, MCV, MCH, MCHC), WBCs and its related indices (polymorphs and lymphocytes) and platelet distribution width (PDW %) whereas platelet count showed significant increase. Nonetheless alone as well as combined treatment of exogenous melatonin and insulin restored all altered hematological parameters. However, significant recovery was found in the group in which combined dose of melatonin and insulin was administrated. Therefore, it might be concluded that combined administration of melatonin and insulin will be better remedy to normalize the altered blood profile during the diabetic condition.

Therapeutic Efficacy of Melatonin Against Polycystic Ovary Syndrome (PCOS) Induced by Letrozole in Wistar Rat.

BACKGROUND AND OBJECTIVES: Polycystic ovary syndrome (PCOS) is a common heterogeneous endocrinological and metabolic disorder in women of reproductive age which leads to infertility/subfertility. The present study was commenced to elucidate the therapeutic efficacy of melatonin in the pathogenesis of letrozole induced polycystic ovary syndrome (PCOS) in Wistar rat. MATERIALS AND METHODS: Letrozole was administered orally (1 mg kg-1) to induce PCOS condition in Wistar female rats for a period of 2-3 weeks followed by a dose of melatonin (200 µg/100 g b.wt.) to PCOS induced rats. On the completion of experimental period the level of cytokines and expression level of different receptors was assessed. RESULTS: The PCOs rats showed down regulation in melatonin (MT1 and MT2), estrogen (ER-α) and cytokine (IL-2R and IL-6R) receptors expression and high circulatory level of IL-6 and TNF-α during PCO condition. These anomalies in expression pattern and circulatory level of cytokines were restored following the treatment. CONCLUSION: Finding of present study showed the role of melatonin supplementation at receptor level and also suggesting a crosstalk between MT1R / MT2R via cytokine IL-2R and IL-6R resulting in modulation of ER-α receptors.

Protective Role of Melatonin in Streptozotocin Induced Pancreatic Damages in Diabetic Wistar Rat.

BACKGROUND AND OBJECTIVE: Hyperglycemia is a representative hallmark and risk factor for diabetes and is closely linked to diabetes associated complications. The aim of the present study was to evaluate the therapeutic potential of exogenous melatonin against the streptozotocin induced pancreatic damages in rats. MATERIALS AND METHODS: Streptozotocin was injected for consecutive 6 days. Diabetes was confirmed by blood glucose measurement after 72 h and on 7th day after injection. Animals having blood glucose level above 250 mg dL-1 were considered as diabetic and were administered exogenous melatonin for 4 weeks. Animals were euthanized after last dose, pancreas were dissected out, weighed and fixed in Bouin's fixative for histology and further tissues were kept at -20°C for biochemistry. RESULTS: Diabetic rats displayed significant increase in lipid peroxidation, but pancreatic weight index, antioxidant system (GSH, SOD and CAT) showed decrease. Melatonin treatment to diabetic rats restored the alteration in physiological and biochemical markers. Results were supported by the histopathological observations, STZ treated pancreas showed damage in islets of langerhans, while as melatonin treated diabetic rats recovered the cellular architecture which inturn normalize the function of the pancreas. CONCLUSION: Therefore, melatonin might be considered as a molecule to protect the pancreatic damages.