Effects of Functional Pinealectomy on Immunity, Hematopoietic, Gastrointestinal and Urinary Systems in Experimentally Malnutritioned Rats

Abstract

Objective: The aim of this study was to demonstrate morphological changes in immunity, hematopoietic, gastrointestinal and urinary systems in different melatonin (MEL) release situations in a rat model of protein energy malnutrition (PEM). Methods: A total of 32 adult male Wistar rats were assigned into four equal groups: normal control; PEM light/dark; PEM light, called functional pinealectomy (Px); and PEM dark. PEM was produced with a 50% restricted diet, Px was produced by keeping rats in continuous light environment for 24 hours, and complete blood count and serum albumin level were analyzed at the end of the 6-week experimental period. Measurements of weights of body and some visceral organs were obtained, biochemical and morphological parameters were analyzed in addition to measurements of malondialdehyde (MDA), total glutatione (GSH), tumor necrosis factor (TNF)-α and interleukin-10 (IL-10) in tissue samples. Results: A reduction in the weights of body and visceral organs of animals in the PEM groups was accompanied by hypoalbuminemia, anemia, leukopenia and lymphopenia, and higher MDA, GSH, TNF-α and IL-10 levels in visceral tissues. There was a significant decrease in parenchymal cells of the liver and spleen, duodenal villi, lymphoid structures and kidney glomeruli, but there was an increase in the spleen capsule thickness and renal Bowman’s space, sinusoidal congestion and fat accumulation in the liver. Importantly, these findings were milder in the PEM dark group, while they were prominent in the PEM light group. Conclusions: This study suggests that MEL has a protective role in reducing the negative effects of PEM, making it a potential therapeutic agent for further investigation.