The Possible Effect of Grape Seed Extract on the Adrenal Cortex in Streptozotocin-Induced Diabetes in Male Albino Rats: A Histological Study

Abstract

Abstract Introduction Induction of diabetes in rat models injected with streptozotocin (STZ) had led to increase activity of the hypothalamic-pituitary-adrenal (HPA) axis accompanied with hypercortisolism and adrenocortical growth. Proanthocyanidin, a grape seed extract (GSE) that was observed to have beneficial effect on different metabolic and inflammatory diseases. Aim To study the structural changes of the adrenal cortex in diabetic rats and the beneficial effect of GSE on the suprarenal cortical injury. Materials and methods 35 adult male albino rats were divided randomly into 4 groups. Group I (control). Group II (GSE), rats received GSE orally (200 mg/kg), daily for 21 days. Group III (STZ), rats were injected with STZ (40 mg/kg) given intraperitoneal once. Group IV (STZ + GSE), rats received STZ as in group III. After rats confirmed to be diabetic, they were treated with GSE as in group II. After 21 days, the adrenal glands from all groups were dissected and processed for light microscopic examination. Morphometric and statistical analysis were also done. Results H&E stained section of Group III (STZ) showed increase in the capsular thickness and congested blood capillaries. Both zona glomerulosa & zona fasciculata showed increased thickness with some cells appeared with vacuolated acidophilic cytoplasm while others were shrunken with closely packed pyknotic nuclei. Inflammatory cells infiltration was also observed. Moreover, silver stain showed focal significant increase in thickness of the capsule, dense trabeculae and dense irregular reticular fibers of the cortex. Meanwhile, immunohistochemical results showed significant increase in the reaction for caspase 3 antibodies. Group IV (STZ + GSE) showed restoration of the cortical structure & organization nearly similar to that of control group. Conclusion It can be considered that GSE might have a protective effect on the structure of diabetic rats’ adrenal gland.