Adaramoye O A, Farombi E O, Nssien M, Idowu S O, Ademowo O G, Adeyemi E O
Department of Biochemistry, University of Ibadan, Ibadan, Nigeria.
J Med Food. 2008 Sep;11(3):544-50. doi: 10.1089/jmf.2007.0539.
The hepatoprotective activity of kolaviron (KV), a biflavonoid complex from Garcinia kola seeds, and its purified fractions was investigated in mice intoxicated with carbon tetrachloride (CCl(4)). The ability of vitamin E to attenuate the toxicity was also examined. KV was extracted from powdered seeds of G. kola and then separated by thin-layer chromatography into three fractions--Fraction I (FI), Fraction II (FII), and Fraction III (FIII), with ratio of fronts values of 0.48, 0.71, and 0.76, respectively. Pretreatment with KV, FI, and FII at a dose of 100 mg/kg of body weight for 2 weeks and then challenge with CCl(4) at a dose of 1.2 g/kg of body weight, three times a week for 2 consecutive weeks, decreased the CCl(4)-induced increase in activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) by 31%, 30%, and 31% and 41%, 55%, and 42%, respectively. CCl(4) intoxication also caused a significant (P < .05) accumulation of lipid peroxidation (LPO) products as revealed by the formation of the thiobarbituric acid-reactive substances: CCl(4) induced LPO levels in serum and microsomes by 112% and 89%, respectively. However, pretreatment with KV, FI, and FII decreased LPO levels in serum by 31%, 41%, and 40% and in microsomes by 48%, 39%, and 35%, respectively. Vitamin E was protective in reducing the CCl(4)-induced increase in levels of AST, ALT, and gamma-glutamyl transferase as well as LPO. Furthermore, CCl(4) intoxication significantly (P < .05) decreased the activities of microsomal glucose-6-phosphatase, aniline hydroxylase, and cytosolic glutathione-S-transferase (GST). While pretreatments with KV, FI, and FII were able to ameliorate the levels of glucose-6-phosphatase and GST, there were no significant (P > .05) effects on the levels of aniline hydroxylase and DT-diaphorase. This study confirms that FI and FII from KV enhanced recovery from CCl(4)-induced hepatotoxicity by decreasing the extent of LPO and also inducing the levels of phase II enzyme (GST). These fractions are responsible for the observed antihepatotoxic effect of KV.
研究了可乐果种子中的双黄酮类化合物可乐维酮（KV）及其纯化组分对四氯化碳（CCl₄）中毒小鼠的肝保护活性。同时也检测了维生素E减轻毒性的能力。从可乐果的种子粉末中提取KV，然后通过薄层色谱法将其分离为三个组分——组分I（FI）、组分II（FII）和组分III（FIII），其比移值分别为0.48、0.71和0.76。以100mg/kg体重的剂量对小鼠进行KV、FI和FII预处理2周，然后以1.2g/kg体重的剂量给予CCl₄进行攻击，连续2周每周3次，结果显示，KV、FI和FII使CCl₄诱导的丙氨酸氨基转移酶（ALT）和天冬氨酸氨基转移酶（AST）活性增加分别降低了31%、30%和31%以及41%、55%和42%。CCl₄中毒还导致脂质过氧化（LPO）产物显著（P<0.05）积累，这通过硫代巴比妥酸反应性物质的形成得以揭示：CCl₄分别使血清和微粒体中的LPO水平升高了112%和89%。然而，用KV、FI和FII预处理分别使血清中的LPO水平降低了31%、41%和40%，使微粒体中的LPO水平降低了48%、39%和35%。维生素E对降低CCl₄诱导的AST、ALT和γ-谷氨酰转移酶水平以及LPO具有保护作用。此外，CCl₄中毒显著（P<0.05）降低了微粒体葡萄糖-6-磷酸酶、苯胺羟化酶和胞质谷胱甘肽-S-转移酶（GST）的活性。虽然用KV、FI和FII预处理能够改善葡萄糖-6-磷酸酶和GST的水平，但对苯胺羟化酶和DT-黄递酶的水平没有显著（P>0.05）影响。本研究证实，KV中的FI和FII通过降低LPO程度并诱导II相酶（GST）水平，增强了CCl₄诱导的肝毒性的恢复。这些组分是观察到的KV抗肝毒性作用的原因。
