Zagoto Janaína Naldi, Bracht Adelar, Pagadigorria Clairce Luzia Salgueiro, Ishii-Iwamoto Emy Luiza, Cortez Diógenes Aparício Garcia, Yamamoto Nair Seiko
Laboratory of Liver Metabolism, Department of Biochemistry, University of Maringá, Avenida Colombo, 5790, 87020900 Maringá, Brazil.
J Ethnopharmacol. 2006 Apr 21;105(1-2):47-54. doi: 10.1016/j.jep.2005.09.036. Epub 2005 Oct 24.
Kielmeyera coriacea Mart is a medicinal plant of the Clusiacea (Guttiferae) family used by the native population of Brazil in the treatment of several tropical diseases such as malaria, schistosomiasis, leishmaniasis, and fungal or bacterial infections. Kielmeyera coriacea is also effective as an antidepressant drug. Extracts of the plant are rich in xanthones. Compounds of this class have been reported to inhibit mitochondrial energy metabolism. For this reason the action of the Kielmeyera coriacea extract on hepatic energy metabolism was investigated in the present work, using isolated rat liver mitochondria and the perfused rat liver. In perfused livers the extract (20-80 microg/ml) caused stimulation of oxygen consumption, inhibition of gluconeogenesis and stimulation of glycogenolysis and glycolysis. In isolated mitochondria the Kielmeyera coriacea extract (5-20 microg/ml) stimulated state IV respiration, reduced the ADP/O ratio and decreased the respiratory coefficient. The activities of succinate-oxidase, NADH-oxidase, NADH dehydrogenase and succinate dehydrogenase were inhibited. The ATPase of intact mitochondria was stimulated and the ATPase of uncoupled mitochondria was inhibited. The results of this investigation suggest that the Kielmeyera coriacea extract impairs the hepatic energy metabolism by acting as mitochondrial uncoupler and inhibitor of enzymatic activities linked to the respiratory chain. The impairment of mitochondrial energy metabolism could lead to adverse metabolic effects by the use of the crude extract, but it could equally be the basis of its antiprotozoan and antifungal effects.
基尔米耶拉厚皮树（Kielmeyera coriacea Mart）是藤黄科（金丝桃科）的一种药用植物，巴西当地居民用它来治疗多种热带疾病，如疟疾、血吸虫病、利什曼病以及真菌或细菌感染。基尔米耶拉厚皮树还具有抗抑郁作用。该植物提取物富含氧杂蒽酮。据报道，这类化合物会抑制线粒体能量代谢。因此，在本研究中，利用分离的大鼠肝线粒体和灌注大鼠肝脏，研究了基尔米耶拉厚皮树提取物对肝脏能量代谢的作用。在灌注肝脏中，提取物（20 - 80微克/毫升）可刺激氧气消耗，抑制糖异生，并刺激糖原分解和糖酵解。在分离的线粒体中，基尔米耶拉厚皮树提取物（5 - 20微克/毫升）可刺激状态IV呼吸，降低ADP/O比值，并降低呼吸系数。琥珀酸氧化酶、NADH氧化酶、NADH脱氢酶和琥珀酸脱氢酶的活性受到抑制。完整线粒体的ATP酶受到刺激，解偶联线粒体的ATP酶受到抑制。本研究结果表明，基尔米耶拉厚皮树提取物通过作为线粒体解偶联剂和与呼吸链相关的酶活性抑制剂来损害肝脏能量代谢。线粒体能量代谢的损害可能会因使用粗提取物而导致不良代谢影响，但这同样可能是其抗原生动物和抗真菌作用的基础。
