Hepatoprotective effects of Allium cepa (onion) extracts against paracetamol-induced liver damage in rats

Liver damage due to paracetamol hepatotoxicity is a major health challenge worldwide. It is against this background that this study was designed to determine the hepatoprotective effects of the increasing dosage of Allium cepa methanolic extracts on paracetamol induced hepatotoxic rats. Fifty-four (54) adult male albino rats comprising of nine normal and 45 paracetamol hepatotoxic rats were used for this study. The experimental design was the three by three Latin square design. Paracetamol hepatotoxicity was induced by single administration of paracetamol at 750 mg/kg ip on the first day of the experiment. The different biochemical parameters assessed were determined before the start of the study and subsequently monthly for the duration of the study. Blood samples were collected from the rat through the eye monthly for analysis and serum was obtained by centrifugation (5000 rpm for 10 min) and stored at -20°C prior to analysis. The effects of duration and increasing dosages (200, 300 and 450 mg/kg) of A. cepa methanolic extracts produced a duration dependent significant (p < 0.05) reductions in the alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and total serum bilirubin (TSB) of paracetamol hepatotoxic rats after the duration of study when compared with those of the paracetamol, normal and silymarin control rats. A. cepa reduced alanine aminotransferase and total serum bilirubin in a dose dependent fashion whereas it reduced aspartate aminotransferase, alkaline phosphatase and lactate dehydrogenase level in a dose independent manner. A. cepa extracts studied showed potent hepatoprotective properties. It was evident that A. cepa extracts was able to reduce significantly all the elevated biochemical parameters due to paracetamol hepatotoxicity and this was collaborated by results of histopathological studies. Keywords: Allium cepa, paracetamol, hepatoprotective effects, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, total serum bilirubin African Journal of Biotechnology , Vol 13(26) 2679-2688