Wu Xin, Yu Xiaochen, Zhu Na, Xu Meihong, Li Yong
Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, China.
Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Peking University Research Center on Aging, Peking University, Beijing, China.
Front Nutr. 2022 Sep 9;9:897821. doi: 10.3389/fnut.2022.897821. eCollection 2022.
Aging-related muscle loss is a hallmark of aging and is the cause of some negative outcomes. An optimized diet and supplements have a positive effect in slowing down the process of muscle loss. D-galactose(d-gal) has been used widely to develop aging model. This study explored the beneficial effects of whey protein peptides (WPPs) on sarcopenia in d-gal-induced aging mice. A total of 72 SPF male C57BL/6N mice were used in this study. Sixty mice were modeled by injected intraperitoneally with d-gal (100 mg/kg body weight for 6 weeks), and the other 12 mice were used as control, and injected with the same amount of normal saline. After 6 weeks, the modeled mice were randomly divided into the model control group, whey protein group (1.5 g/kgbw), and three WPPs intervention groups (0.3 g/kgbw, 1.5 g/kgbw, 3.0 g/kgbw), according to serum malondialdehyde (MDA) level. The test samples were orally given to mice by daily garaged. During the 30 days intervention period, the model control group, whey protein group, and WPPs group continued receiving intraperitoneal injections of d-gal, whereas the control group continued receiving intraperitoneal injections of normal saline. The results showed that WPPs could significantly improve the grip strength of aged mice. WPPs could significantly increase lean mass of aged mice and increase muscle weight of gastrocnemius and extensor digitorum longus. WPPs could significantly increase the level of insulin-like growth factor-1 (IGF-1) and reduce level of interleukin (IL)-1, IL-6, tumor necrosis factor-alpha (TNF-α) in serum. WPPs could affect the muscle fiber size in d-gal-induced aging mice. Its specific mechanism may be related to the activation of IGF-1/Akt/mTOR protein synthesis signaling pathway and reduction of the level of inflammation. These results indicate that WPPs can improve aging-related sarcopenia. Compared with whey protein, WPPs supplement seems a better form for sarcopenia.
与衰老相关的肌肉流失是衰老的一个标志，也是一些负面结果的原因。优化饮食和补充剂对减缓肌肉流失过程具有积极作用。D-半乳糖（D-gal）已被广泛用于建立衰老模型。本研究探讨了乳清蛋白肽（WPPs）对D-gal诱导的衰老小鼠肌肉减少症的有益作用。本研究共使用了72只SPF级雄性C57BL/6N小鼠。60只小鼠通过腹腔注射D-gal（100 mg/kg体重，持续6周）建立模型，另外12只小鼠作为对照，注射等量的生理盐水。6周后，根据血清丙二醛（MDA）水平，将建模小鼠随机分为模型对照组、乳清蛋白组（1.5 g/kgbw）和三个WPPs干预组（0.3 g/kgbw、1.5 g/kgbw、3.0 g/kgbw）。通过每日灌胃将测试样品给予小鼠。在30天的干预期内，模型对照组、乳清蛋白组和WPPs组继续接受腹腔注射D-gal，而对照组继续接受腹腔注射生理盐水。结果表明，WPPs可显著提高衰老小鼠的握力。WPPs可显著增加衰老小鼠的瘦体重，并增加腓肠肌和趾长伸肌的肌肉重量。WPPs可显著提高血清中胰岛素样生长因子-1（IGF-1）水平，并降低白细胞介素（IL）-1、IL-6、肿瘤坏死因子-α（TNF-α）水平。WPPs可影响D-gal诱导的衰老小鼠的肌纤维大小。其具体机制可能与激活IGF-1/Akt/mTOR蛋白合成信号通路及降低炎症水平有关。这些结果表明，WPPs可改善与衰老相关的肌肉减少症。与乳清蛋白相比，补充WPPs似乎是治疗肌肉减少症的更好形式。
