Hsu Hseng-Kuang, Yang Yu-Chiao, Hwang Jia-Huae, Hong Show-Jen
Department of Physiology, Kaohsiung Medical University, Kaohsiung, Taiwan.
Kaohsiung J Med Sci. 2003 Aug;19(8):385-90. doi: 10.1016/S1607-551X(09)70481-4.
The effect of substances extracted from Toona sinensis leaves with 50% alcohol solution on lipolysis was investigated in cultured 3T3-L1 differentiated adipocytes. The amount of glycerol released from cells into culture medium was used to measure lipolysis activity. Glycerol release was increased by Toona sinensis leaf extract in a dose-dependent and time-dependent manner. Following treatment of 3T3-L1 adipocyte cells with various concentrations of Toona sinensis leaf extract (0.001, 0.01, and 0.1 mg/mL) for 6 hours, the amounts of glycerol released from 3T3-L1 cells increased from a control value of 99 nmol/mg protein to 127, 144, and 154 nmol/mg protein, respectively. The lipolytic effect of Toona sinensis leaf extract was not inhibited by pretreatment of cells with cycloheximide, econazole, baicalein, or indomethacin. However, the lipolytic activity induced by Toona sinensis leaf extract was diminished by dibutyryl cyclic adenosine-5'-monophosphate (dibutyryl cAMP) and the protein kinase C inhibitor calphostin C. These results indicate that the lipolytic effect induced by Toona sinensis leaf substances may be involved in the protein kinase C pathway and may be down-regulated by cAMP.
研究了用50%乙醇溶液从香椿叶中提取的物质对培养的3T3-L1分化脂肪细胞脂解作用的影响。用细胞释放到培养基中的甘油量来测量脂解活性。香椿叶提取物以剂量和时间依赖性方式增加甘油释放。用不同浓度（0.001、0.01和0.1mg/mL）的香椿叶提取物处理3T3-L1脂肪细胞6小时后，3T3-L1细胞释放的甘油量分别从对照值99nmol/mg蛋白增加到127、144和154nmol/mg蛋白。用环己酰亚胺、益康唑、黄芩素或吲哚美辛预处理细胞不会抑制香椿叶提取物的脂解作用。然而，二丁酰环腺苷-5'-单磷酸（二丁酰cAMP）和蛋白激酶C抑制剂钙磷蛋白C会减弱香椿叶提取物诱导的脂解活性。这些结果表明，香椿叶物质诱导的脂解作用可能与蛋白激酶C途径有关，并且可能被cAMP下调。
