Abstract
The aim of this study was to evaluate the effect of Olive Leaf Extracts (OLE) on the haematology and biochemistry as well as on the liver and kidney of rats fed on the extracts for 6 weeks. Thirty Wistar albino rats were divided into five groups, Group 1 fed regular diet without OLE (control group), group 2 (fed 0.2% ole), group 3 (fed 0.4% ole), group 4 (fed 0.7% OLE) and group 5 (fed 0.9% OLE) for 6 weeks. Serum concentrations of Alkaline Phosphatase (ALP), Lactate Dehydrogenase (LDH), Total Bilirubin (TBil) and cholesterol, glucose, triglycerides as well as hematological profiles were determined in the present study for each group of rats. There was a significant increase in the serum levels of ALP and total bilirubin in groups 3 and 4 and 5 compared to the control group. There was also significant decrease in the serum triglyceride, glucose and cholesterol in test groups as compared to the control group. The haematological profile showed significant decrease in the values of red blood cell counts, haemoglobin and packed cell volume of the animals in group 5. Microscopically both liver and kidneys showed histological alterations in the firm of fatty cytoplasmic vacuolation, necrosis of the hepatocytes and a slight hemorrhage was recorded in the kidneys of the experimental animals especially those fed 0.9% olive leaf extract. The olive leaves extract should be handled with care in arts and other animals and special attention should be paid when using OLE for longer periods of time and at higher doses as it may result in an undesirable effect on liver and kidneys as it has been shown in the present study.