Pathological studies on nanosilica administered Wistar rats
Loading...
Files
Date
2019-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand)
Abstract
The present study investigated the toxicopathological effects of nanosilica at NOAEL dose in Wistar rats for a period of 90 days. A total of 35 rats of 6 weeks age were divided randomly into group I (control) and group II (treatment). Group II rats were administered nanosilica orally at NOAEL dose (2000mg/kg). A significant time dependent decrease in body weight, relative weight of liver and growth rate were observed in group II rats as compared to group I rats. There were non- significant variations in haemoglobin (Hb), packed cell volume (PCV), total erythrocyte count (TEC) and erythrocytic indices between the groups. PCV and MCH varied significantly within the group. The total leucocyte (TLC) decreased significantly in group II rats as compared to group I rats. In differential leucocyte count, lymphocytes, neutrophil, monocyte, eosinophil and basophil did not vary significantly neither between the groups nor within the groups. In group II rats, serum total protein, serum albumin and globulin revealed no significant change when compared to group I rats. Within the group II rats, serum total protein, albumin and globulin varied significantly. Serum aspartate aminotransaminases (AST) and alanine aminotransaminases (ALT) increased significantly both between groups I & II and within the group II. Cholesterol increased significantly in group II. Creatinine and blood urea nitrogen (BUN) were significantly increased in group II. Immunological studies revealed insignificant variations in humoral and cell mediated immunity (CMI) in group II. Grossly cysts were present on surface of liver of group II rats. Histopathologically, liver of group II rats exhibited vascular changes, mononuclear cells infiltration, dilated sinusoidal spaces, kupffer cells hyperplasia, degeneration and necrosis of hepatocytes. Lungs in group II revealed atelectasis, emphysema, congestion and infiltration of mononuclear cells and thickening of interalveolar septa. Kidneys in group II revealed mononuclear cell infiltration in interstitium, alterations in glomeruli, necrosis and sloughing of tubular epithelial cells and obliteration of tubular lumen. In group II, intestine revealed increased goblet cells, necrosis and desquamation of epithelium. Spleen in group II revealed decreased in white pulp and necrosis of lymphoid cells at few places leading to depletion of lymphoid tissue. Heart of group II rats revealed vascular changes and necrosis of cardiomyocytes was observed. In group II thymus vascular changes, mild necrosis and depletion of lymphoid tissue were observed. In brain of group II rats, degeneration, necrosis of neurons and neuronophagia was observed. Ultrastructural studies in liver and kidney revealed accumulation of nanosilica in lysosomes and mitochondria, apoptosis of hepatocytes and mitochondrial damage. Collectively, these observations indicated that nanosilica have toxic effects as hepatopathy, nephropathy and immunopathy at NOAEL dose.
Description
Keywords
null