Antioxidant and cytotoxic activities of canadine: biological effects and structural aspects.
ABSTRACT The cytotoxic effects of four alkaloids, berberine, canadine, anonaine, and antioquine were evaluated using three different cell cultures, a primary culture (rat hepatocytes) and two cell lines (HepG2 and HeLa). Our results indicate that berberine, anonaine, and antioquine possess a significant the cytotoxic effect. In contrast, canadine does not possess cytotoxic effect at concentrations tested here. A molecular modeling study indicates that the quaternary nitrogen, the aromatic polycyclic and planar structure of berberine could be the pharmacophoric patron to produce the cytotoxic effect. In parallel our results demonstrated that canadine possess a significant antioxidant activity. Stereoelectronic aspects of this alkaloid were found to be closely related to those displayed by alpha-tocopherol and its water-soluble analogue trolox. The antioxidant activities of canadine, combined with its low-toxic effect, indicated that the potential of this alkaloid as a novel class of antioxidant agent is very interesting and deserves further research.
- SourceAvailable from: courses.chem.psu.edu
- [show abstract] [hide abstract]
ABSTRACT: The ripe fruit of Terminalia chebula RETZIUS (T. chebula RETZ) (Combretsceae), which is a native plant in India and Southeast Asia, has traditionally been used as a popular folk medicine for homeostatic, antitussive, laxative, diuretic, and cardiotonic treatments. The objective of this study was to evaluate the protective effects of an aqueous extract of fruit of T. chebula on the tert-butyl hydroperoxide (t-BHP)-induced oxidative injury observed in cultured rat primary hepatocytes and rat liver. Both treatment and pretreatment of the hepatocytes with the T. chebula extract (TCE) significantly reversed the t-BHP-induced cell cytotoxicity and lactate dehydrogenase leakage. In addition, TCE exhibited in vitro ferric-reducing antioxidant activity and 2,2-diphenyl-1-picryhydrazyl free radical-scavenging activities. The in vivo study showed that pretreatment with TCE (500 or 1000 mg/kg) by gavage for 5 d before a single dose of t-BHP (0.1 mmol/kg i.p.) significantly lowered the serum levels of the hepatic enzyme markers aspartate aminotransferase and alanine aminotransferase and reduced the indicators of oxidative stress in the liver, such as the glutathine disulfide content and lipid peroxidation, in a dose-dependent manner. Histopathologic examination of the rat livers showed that TCE reduced the incidence of liver lesions, including hepatocyte swelling and neutrophilic infiltration, and repaired necrosis induced by t-BHP. Based on the results described above, we speculate that TCE has the potential to play a role in the hepatic prevention of oxidative damage in living systems.Biological & Pharmaceutical Bulletin 10/2005; 28(9):1639-44. · 1.85 Impact Factor