Effect of Induced Vitamin D Deficiency on The Pancreas of Albino Rats

Abstract

Vitamin D is now considered one of the most important rich fields for research work because of its major role in many aspects of health. Previously it was believed that vit.D concerned only with the homeostasis of Ca but now it is proved to have a crucial role in endocrine and immune system modulation. There are two types of the vitamin, vit.D3 (cholecalciferol) formed mainly in the skin and vit.D2 (ergocalciferol) of diet sources. Both are inactive and need activation in two steps firstly in the liver and then in the kidney. Vitamin D exerts its action via nuclear receptors (VDR) that are present in many tissuses including the pancreatic β cells. The deficiency state of the vitamin is considered to be established when the level of 25(OH) Vit. D reach <20 ng/ ml. It is belived that vit.D contributes in the pathogenesis of both types of Diabetes mellitus (DM). It is not only important for insulin secretion but also improve the insulin sensitivity of the target cells. So the aim of the present study was to detect the effect of induced vitamin D deficiency on the blood glucose level and the structure of the pancreas. A total of twenty four male Sprague-Dawleyalbino rats were divided into two groups. Group I, consisted of 6 rats as the control group and Group II, consisted of 18 rats were further subdivided into group IIa of 9 rats subjected to vit.D deficiency diet for one month and group IIb of 9 rats subjected to vit.D deficiency diet for two months. Light microscopic examination of sections of pancreas stained with H&E, Masson’s trichrome and Toluidine blue stains revealed changes in the structure of the islets of Langerhans. These changes were more marked in the rats subjected to the deficient diet for two months than in rats fed the deficient diet for only one month.There were reduction in the number, size and total mass of the islets. The islet cells themselves were decreased. Some nuclei showed pyknotic features. Statistical analysis of the blood glucose levels showed nonsignificant increase in rats subjected to the deficient diet for one month compared with those of the control group, while showed significant increase in rats subjected to vit.D deficient diet for two months.