Immunohistochemical and Histochemical Studies of Β-Cells Insulin Up-Regulation in Pancreatic Tissues of Streptozotocin-Induced Diabetic Albino Rats Treated with Melatonin and Magnesium

Background: Improve insulin secretion and cellular availability to reduced blood glucose levels in diabetic subjects by bioactive compound especially antioxidants are the new focus to ameliorate the complication with diabetes mellitus. Aims and objectives: The aim of this study was to evaluate the effects of administration of melatonin and magnesium on the cytoarchitecture of the pancreatic tissue and to access immunohistochemically insulin release in streptozotocin-induced diabetic Albino rats. Materials and methods: To achieve this aim six normoglycaemic rats and fourty eight Streptozotocin (STZ) induced diabetic rats was used in the study after two weeks acclimatization period. The animals were assigned into nine groups as follows, Normal control group (NC), Diabetic control (DC) group, Melatonin at 10 mg/kgb (MLD), magnesium dose group of 240 mg/kgbw (MgLD), melatonin and magnesium combined group of 10mg/kgbw+240mg/kgbw (MMgLD), melatonin group of 20mg/kgbw (MHD), melatonin and magnesium high dose combined group of 20mg/kgbw+480mg/kgbw (MMgHD) and insulin at 500mg/kgbw group (IN). Melatonin and insulin were administered through intraperitoneal injections (IP) while magnesium was by oral administration. The control groups were given placebo and all groups’ treatment was for twenty-one days. At the end of the study, the animals were aestheticized and euthanized to harvest pancreatic organ. The organs were fixed in neutral buffered formaldehyde (NBF). They were histologically prepared and stained using haematoxylin and eosin and immunohistochemically stained using insulin antibody to access insulin release. Results: Melatonin treatment at 10mg/kgbw and at 20 mg/kgbw showed histological improvement in histological tissues and insulin release while when combined with magnesium at dose of 10mg/kgbw and at 240 mg/kgbw showed better results. The administration of magnesium at 240 mg/kgbw, 480 mg/kgbw and when combined with melatonin at high doses does not show significant improvement in islet β-cell proliferation and insulin release. Conclusion: The administration of melatonin and magnesium at low doses regenerates pancreatic islet histoarchitecture and augments insulin release from treated diabetic albino rats.