Cighetti G, Del Puppo M, Paroni R, Fiorica E, Galli Kienle M
J Lipid Res. 1987 Feb;28(2):152-61.
The effects of pantethine on cholesterol and fatty acid metabolism were investigated in isolated rat hepatocytes. Preincubation of the cells with pantethine induced a concentration-dependent decrease of the radioactivity incorporated into carbon dioxide and lipids in incubations with [2-14C]acetate. When pantethine and the labeled substrate were simultaneously added to the cell suspension, there was an enhancement of carbon dioxide radioactivity at short incubation time (5 min) whereas, at longer incubation time, values were comparable to those of controls; lipid radioactivity, instead, was dramatically reduced by pantethine even at short incubation time and decreased further during the incubation, being 23% of that of controls at 60 min. Analysis of the incubation medium showed that pantethine induced a concentration- and time-dependent release of acetate into the medium. Results of the effect of the acetate concentration on the incorporation of [2-14C]acetate radioactivity into CO2 and lipids in control hepatocytes allowed the conclusion that the above-described modifications induced by pantethine are only partially attributable to the dilution of the labeled substrate, and that catabolism of acetate to carbon dioxide is stimulated by the disulphide pantethine, whereas cholesterol and fatty acid syntheses are inhibited.
在分离的大鼠肝细胞中研究了泛硫乙胺对胆固醇和脂肪酸代谢的影响。用泛硫乙胺预孵育细胞会导致在与[2-¹⁴C]乙酸盐孵育时,掺入二氧化碳和脂质中的放射性呈浓度依赖性降低。当将泛硫乙胺和标记底物同时添加到细胞悬液中时,在短孵育时间(5分钟)时二氧化碳放射性增强,而在较长孵育时间时,其值与对照相当;相反,即使在短孵育时间,泛硫乙胺也会使脂质放射性显著降低,并且在孵育过程中进一步降低,在60分钟时为对照的23%。对孵育培养基的分析表明,泛硫乙胺会导致乙酸盐浓度和时间依赖性地释放到培养基中。乙酸盐浓度对对照肝细胞中[2-¹⁴C]乙酸盐放射性掺入二氧化碳和脂质的影响结果表明,泛硫乙胺引起的上述变化仅部分归因于标记底物的稀释,并且二硫化泛硫乙胺会刺激乙酸盐分解为二氧化碳,而胆固醇和脂肪酸合成则受到抑制。