Role of Coconut Oil and Vitamin D in Alleviating Glucose, C-peptide and Histological Alterations in the Hepatic Tissues of Hyperglycemic albino rats

Abstract

The purpose of the present study is to evaluate the effect of either vitamin D or coconut oil or both together on the histological changes of the hepatic tissues of diabetic adult male albino rats induced by using streptozotocin (STZ). The rats were divided into 7 equal groups (10 rats/each). The duration of the experiment was 4 weeks. Gp.I: normal control rats group without any treatments. Gp.II & Gp.III: non-diabetic rat groups received coconut oil in a dose of 7.5 ml /kg b.w/daily or vitamin D orally in a daily dose of 500 IU/kg b.w/daily, respectively. Gp. IV: diabetic rats group injected i.p. with a single dose of STZ dissolved in saline solution in a dose of 60 mg/kg b.w to induce diabetes. Gps.V, VI & VII: diabetic rats administered orally at the same previous doses with coconut oil or vitamin D or both together. The results recorded non-significant changes in the blood glucose and C-peptide levels of non-diabetic group. Significant increase in blood glucose level and a significant decrease in C-peptide of diabetic group as compared to the normal control ones. Diabetic group that received the coconut oil or vitamin D recorded a decrement in blood glucose levels and an increment in C-peptide; while the diabetic rats co-administered with vitamin D and coconut oil recorded a highly significant decrease in blood glucose levels and a highly significant increase in C-peptide as compared to diabetic group. Histologically, the rats of normal control group or that received either coconut oil or vitamin D showed normal structure of the liver tissue with H&E stain. The liver lobules are roughly hexagonal, and consist of plates of hepatocytes radiating from a central vein. The central vein joins to hepatic vein to carry blood out from liver. Between the hepatocyte plates are liver sinusoids, which are lined with two types of cells sinusoidal endothelial cells and phagocytic Kupffer cells. The diabetic rats demonstrated many histopathological changes in the liver tissue included loss of normal liver architecture, degeneration of hepatocytes, appearance of pyknotic nuclei, dilated and congested of central vein surrounded by fibrosis, dilation of hepatic sinusoids, proliferation of Kupffer cells, and infiltration of leucocytes. The diabetic rats administered with either coconut oil or vitamin D elucidated improvement of liver histology, few pyknotic nuclei were seen, slight dilatation in sinusoids and decrement of inflammatory cells. While diabetic rats given both coconut oil and vitamin D together detected obvious improvement in the liver structure with the appearance of normal hepatocytes.