Jia Shaohui, Wu Qiming, Wang Shue, Kan Juntao, Zhang Zhao, Zhang Xiping, Zhang Xuejun, Li Jie, Xu Wenhan, Du Jun, Wei Wei
Hubei Collaborative Innovation Center for Sports Intervention and Health Promotion, Wuhan Sports University, Wuhan, China.
Amway (Shanghai) Innovation & Science Co., Ltd., Shanghai, China.
Front Nutr. 2022 Jul 7;9:878229. doi: 10.3389/fnut.2022.878229. eCollection 2022.
It is generally considered that protein supplementation and resistance exercise significantly increase muscle mass and muscle growth. As the hydrolysis products of proteins, peptides may play the crucial role on muscle growth. In this study, male rats were orally administrated 0.4 g/kg body weight of pea peptide combined with 8 weeks of moderate intensity resistance exercise training. After treatment, the body gains, upper limb grip, muscle thickness, and wet weight of biceps brachii were tested, and the cross-sectional area of biceps brachii muscle fiber and the types of muscle fibers were determined by HE staining, immunofluorescence staining, and lactate dehydrogenase activity, respectively. Western blot analysis was used to investigate the level of growth-signaling pathway-related proteins. The results showed that pea peptide supplementation combined with resistance exercise training significantly increased body weight, upper limb grip, muscle thickness, wet weight of biceps brachii, and cross-sectional area of muscle fiber. Meanwhile, pea peptide supplementation obviously elevated the ratio of fast-twitch fiber (type II) and the expression of muscle growth-signaling pathway-related proteins. In addition, the PP2 oligopeptide in pea peptide with the amino acid sequence of LDLPVL induced a more significant promotion on C2C12 cell growth than other oligopeptides.
一般认为，补充蛋白质和进行抗阻运动可显著增加肌肉量和促进肌肉生长。作为蛋白质的水解产物，肽可能在肌肉生长中发挥关键作用。在本研究中，给雄性大鼠口服0.4 g/kg体重的豌豆肽，并结合8周的中等强度抗阻运动训练。处理后，检测体重增加量、上肢握力、肌肉厚度和肱二头肌湿重，并分别通过HE染色、免疫荧光染色和乳酸脱氢酶活性测定肱二头肌肌纤维的横截面积和肌纤维类型。采用蛋白质免疫印迹分析来研究生长信号通路相关蛋白的水平。结果表明，补充豌豆肽并结合抗阻运动训练可显著增加体重、上肢握力、肌肉厚度、肱二头肌湿重和肌纤维横截面积。同时，补充豌豆肽明显提高了快肌纤维（II型）的比例以及肌肉生长信号通路相关蛋白的表达。此外，氨基酸序列为LDLPVL的豌豆肽中的PP2寡肽比其他寡肽对C2C12细胞生长的促进作用更显著。
