Histomorphological Evaluation of Azadirachta indica Linn Ethanolic Leaves Extract on Visceral Organs of Streptozotocin-induced Hyperglycemic Wistar Rats (Rattus norvegicus Albinus)

Abstract

Changes in tissue and organ morphology can occur with the use of herbs for prophylactic and chemotherapy purposes and are mainly detected using expensive biochemical markers. This study therefore examined the histomorphological effects of Azadirachta indica leaves extract on the visceral organs of streptozotocin-induced hyperglycaemic Wistar rats using special histological stains. Thirty-five streptozotocin-induced hyperglycaemic male Wistar rats were grouped into five groups (n=7): diabetes not induced–control; diabetic not treated–control; diabetic treated with Metformin–control; and diabetic treated with 250mg/kg and 500mg/kg per body weight. All groups were treated for 42 days. Fasting blood glucose was measured every week. The rats were sacrificed on day 42, and blood collected through cardiac puncture was used for liver and kidney function tests, while the harvested liver, kidney and pancreas were used for oxidative stress and inflammatory tests, histologically processed and stained with special histological stains for microscopic examination. Data were subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) version 20.0, and P<0.05 was considered significant. Fasting blood glucose levels significantly decreased every week in Wistar rats treated with 250mg/kg and 500mg/kg (P<0.05). The liver and kidney enzymatic activities, superoxide dismutase, Malondialdehyde, interleukin 6, caspase and tumour necrotic factor in diabetic groups treated with 250 mg/kg and 500 mg/kg increased tremendously (P<0.05). In untreated diabetic Wistar rats, the kidney, liver and pancreas tissues showed gross inflammation, atrophic glomeruli, degenerated epithelial cells, thickened basement membranes, collagen fibre deposition, glycogen accumulation, fibrosis, weakened reticulin fibres and degenerated islets of Langerhan’s, whereas all these features were absent in Wistar rats treated with 500 mg/kg ethanolic leaves extract of Azdirachta indica. Histological special stains revealed that Azadirachta indica ethanolic leaves extract preserved and repaired the tissue architecture of the liver, kidney and pancreas against diabetes-associated abnormalities in these visceral organs.