Beneficial effects of allicin on lead induced tissue enzyme alterations in common carp (Cyprinus carpio)

Abstract

Introduction: In toxicological studies, the alterations in the<br><br>enzymatic activities directly reflect the metabolic disturbances and<br><br>cell damage in specific organs. The aim of the current study was to<br><br>determine the effects of lead exposure on tissue enzyme activities of<br><br>aspartate aminotransferase (AST), alanine aminotransferase (ALT),<br><br>alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in<br><br>selected tissues of common carp and also to evaluate the beneficial<br><br>effects of allicin, the main active constituent of garlic, on modulating<br><br>enzyme alterations.<br><br>Methods: Common carp (Cyprinus carpio; total, n=60) were<br><br>divided randomly into three groups of 20 each. Group I fish were<br><br>reared in normal freshwater and served as the control. Group II fish<br><br>were exposed to lead acetate (7.0 mg L−1) for 10 days. Group III fish<br><br>were exposed to lead acetate (7.0 mg L−1) for 10 days and also<br><br>received dietary allicin (10 mg/kg body weight, daily) during lead<br><br>acetate treatment. At the end of each exposure, enzyme activities in<br><br>prepared tissue homogenates were determined using colorimetric<br><br>methods.<br><br>Results: Lead exposure caused a significant elevation of AST, ALT<br><br>and LDH in the liver, as compared to control group (P&lt;0.05). The<br><br>AST, ALT, ALP and LDH levels in kidney homogenates were<br><br>considerably increased following lead exposure, although these<br><br>increases were only significant for ALT and ALP values. Significant<br><br>increases of brain ALT and gill ALP activities were also observed<br><br>following lead exposure. However, alterations in the activities of<br><br>other measured enzymes in both brain and gill of experimental<br><br>groups were not significant.<br><br>Conclusion: Allicin supplementation was effective in attenuating<br><br>the increase in Pb-induced tissue enzyme activities in the most<br><br>organs; therefore it might have some protective and therapeutic<br><br>effects on lead poisoning. However, much more extensive biochemical<br><br>and toxicological research are needed for better understanding of<br><br>the molecular basis of lead induced tissue enzyme alterations and<br><br>ameliorative properties of allicin.