Caloric restriction (CR) is proposed as a strategy to prevent age-related alterations as impaired glucose metabolism and intensification of oxidative stress. In this study, we examined effects of aging and CR on the activities of glycolytic enzymes and parameters of oxidative stress in the cerebral cortex, liver, and kidney of middle-aged (9 months old) and old (18 months old) C57BL6/N mice. Control middle-aged and old mice were fed (AL groups), whereas age-matched CR groups were subjected to CR (70% of food amount) for 6 and 12 months, respectively. There were no significant differences in the activities of key glycolytic and antioxidant enzymes and oxidative stress indices between the cortices of middle-aged and old AL mice. The livers and kidneys of old AL mice showed higher activity of glucose-6-phosphate dehydrogenase, an enzyme that produces NADPH in the pentose phosphate pathway, compared to those of middle-aged mice. CR regimen modulated some biochemical parameters in middle-aged but not in old mice. In particular, CR decreased oxidative stress intensity in the liver and kidney but had no effects on those parameters in the cerebral cortex. In the liver, CR led to lower activities of glycolytic enzymes, whereas its effect was the opposite in the kidney. The results suggest that during physiological aging there is no significant intensification of oxidative stress and glycolysis decline in mouse tissues during the transition from middle to old age. The CR regimen has tissue-specific effects and improves the metabolic state of middle-aged mice.

中文翻译：

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热量限制对中老年小鼠大脑皮层、肝肾氧化应激及关键糖酵解酶的影响

热量限制（CR）被认为是预防与年龄相关的变化（如葡萄糖代谢受损和氧化应激加剧）的策略。在本研究中，我们检查了衰老和CR对中年（9个月大）和老年（18个月大）C57BL6/N大脑皮层、肝脏和肾脏中糖酵解酶活性和氧化应激参数的影响老鼠。对照中年和老年小鼠（AL组）进行喂养，而年龄匹配的CR组则进行CR（食物量的70%）分别喂养6个月和12个月。中老年AL小鼠皮质关键糖酵解酶和抗氧化酶活性以及氧化应激指标无显着差异。与中年小鼠相比，老年 AL 小鼠的肝脏和肾脏显示出更高的葡萄糖-6-磷酸脱氢酶活性，这是一种在戊糖磷酸途径中产生 NADPH 的酶。CR方案调节了中年小鼠的一些生化参数，但对老年小鼠没有调节作用。特别是，CR 降低了肝脏和肾脏的氧化应激强度，但对大脑皮层的这些参数没有影响。在肝脏中，CR 导致糖酵解酶活性降低，而在肾脏中则相反。结果表明，在生理衰老过程中，从中年向老年过渡期间，小鼠组织中的氧化应激和糖酵解下降并没有显着加剧。CR方案具有组织特异性作用，改善中年小鼠的代谢状态。