ABSTRACT The study fabricated a whey protein isolate‐proanthocyanidins (WPI‐PC) non‐covalent complex, and evaluated its anti‐muscle atrophy effects based on the D‐galactose‐induced C2C12 senescent cell model and the sarcopenia mouse model. Results showed the complex's optimal preparation conditions: reaction time 1 h, pH 6.5, and WPI:PC = 1:1. Under the above conditions, at sample concentrations of 5 mg/mL and 1 mg/mL, the protein digestibility and DPPH radical scavenging rate reached 86.67 ± 0.97% and 60.74 ± 0.45%, respectively. The antioxidant capacity of the WPI‐PC complex was significantly increased compared with WPI, while the protein digestibility of the WPI‐PC complex was decreased. 4 mg/mL WPI‐PC complex significantly increased the proliferation rate of C2C12 cells induced by 0.32 M and 0.16 M D‐galactose by 33.50% and 30.45%, respectively. The sarcopenia mouse model results showed that gavage of the WPI‐PC complex significantly increased superoxide dismutase (SOD), while malondialdehyde (MDA) and 8‐hydroxy‐2'‐deoxyguanosine (8‐OHdG) contents were markedly lower relative to model group ( P < 0.05). Gavaged of WPI‐PC‐L (250 mg/kg/d.bw) significantly increased the levels of skeletal muscle mass index (SMI) relative to the model group ( P < 0.05). The WPI‐PC complex significantly elevated muscle cross‐sectional area and type II muscle fibers proportion ( P < 0.05). In conclusion, the WPI‐PC complex could alleviate oxidative stress, thereby improving skeletal muscle atrophy. This study demonstrated great application potential of natural active ingredients and proteins in alleviating age‐related diseases through non‐covalent complexation.
Yang et al. (Wed,) studied this question.