Economos A C, Ballard R C, Miquel J, Binnard R, Philpott D E
Exp Gerontol. 1982;17(2):105-14. doi: 10.1016/0531-5565(82)90043-2.
Thiazolidine carboxylic acid (TCA) is a natural liver metabolite whose Mg-salt increased lifespan of flies and mice (Miquel and Economos, 1979, Exp. Geront. 14: 279). We studied the physiological and cellular fine structural effects of various concentrations of TCA in the food of male Drosophila. Flies on 0.3% TCA at 27 degrees C had a reduced oxygen consumption rate (about 20% less than controls) at 3 wks of age while their mating capacity and speed of mating were preserved; the flies lived in various experiments 20-30% longer than controls. Apparently TCA improved the metabolic efficiency of the flies (possibly from less "waste" of energy due to improved mitochondrial coupling). However, flies on 0.9% TCA had a reduced mating capacity and lifespan (:toxicity) while at 0.1% TCA was ineffective. A similar dose-response relationship was found in young flies treated with TCA for 1 week and then deprived of food and water, a procedure found to induce accelerated physiological aging. TCA at the 0.3% and 0.6% level reduced the speed of development and the size of the enclosed flies. Electron microscopic investigation of wing muscle showed that 0.3% TCA had a protective effect on cellular fine structure. Though in starved controls (40% survivors after 24 hours of starvation) there was a total absence of glycogen granules, and a striking shrinkage and densification of mitochondria, TCA to a large extent protected muscle cells from these effects of starvation.
噻唑烷羧酸（TCA）是一种天然的肝脏代谢产物，其镁盐可延长果蝇和小鼠的寿命（Miquel和Economos，1979年，《实验老年学》14：279）。我们研究了不同浓度的TCA添加到雄性果蝇食物中所产生的生理和细胞精细结构效应。在27摄氏度下，食用0.3% TCA的果蝇在3周龄时耗氧率降低（比对照组低约20%），但其交配能力和交配速度得以保留；在各种实验中，这些果蝇的寿命比对照组延长了20%-30%。显然，TCA提高了果蝇的代谢效率（可能是由于线粒体偶联改善，减少了能量的“浪费”）。然而，食用0.9% TCA的果蝇交配能力和寿命降低（毒性作用），而0.1% TCA则无效。在用TCA处理1周后再剥夺食物和水的年轻果蝇中也发现了类似的剂量反应关系，这一过程被发现会加速生理衰老。0.3%和0.6%水平的TCA降低了发育速度和羽化果蝇的大小。对翅肌的电子显微镜研究表明，0.3%的TCA对细胞精细结构有保护作用。虽然在饥饿对照组（饥饿24小时后40%存活）中完全没有糖原颗粒，线粒体显著收缩和致密化，但TCA在很大程度上保护了肌肉细胞免受饥饿的这些影响。
