Abstract

The effects of ethanol extract of Azadirachta indica (family: meliaceae) leaves on immunological and haematological parameters of alloxan-induced diabetic rats were investigated with a view to ascertaining its involvement in the immunological or inflammatory control of diabetic vascular complications. Total white blood cell, red blood cell, total lymphocyte and neutrophil counts were determined by microscopy. CD₄⁺ cell counts by flow cytometry as well as packed cell volume (PCV), and haemoglobin determination by spectrophotometry were also performed on normal control (NC) and diabetic rats treated orally for 14 days with 400 mg/kg bodyweight of A. Indica leaf extract (DTAI) or 7.14 mg/kg bodyweight of chlorpropamide (DTCH) or distilled water (DC). The different groups comprised of six rats each. The result showed that total white blood cells, total lymphocytes and CD₄⁺ cells were significantly (p < 0.05) increased in untreated diabetic (DC) rats compared to normal control (NC) rats, whereas the increase in neutrophil was not significant. These immunological parameters in diabetic rats treated with the extract (DTAI) and those treated with chlorpropamide (DTCH) were not different from those of the normal control group. Also PCV, haemoglobin concentration and red blood cell count were not significantly different among the test and control groups. The immune cell lowering effects of the A. indicaleaf extract appeared to be of clinical significance in the control of atherosclerosis and other diabetic vascular complications in rats. These effects were comparable to those of chlorpropamide on the immune cells.

Key words: Azadirachta indica, immune cells, atherosclerosis, vascular complications.