(A) The ratios of heart weight/tibia length (HW/TL), liver weight/body weight (BW), and spleen weight/BW were not significantly changed after 6-week administration of rhMG53 in aged mice versus the saline group. (B) Serum levels of ALT, ALP, and total bilirubin in mice treated with saline or rhMG53. (C) Serum levels of LDL, HDL, and triglycerides in mice treated with saline or rhMG53. (D) Serum levels of LDH and CK in mice treated with saline or rhMG53. Open symbols, male mice; closed symbols, female mice. Data are expressed as mean ± SEM. Differences were analyzed for significance by an unpaired t test (A–D); P values are presented in the individual panels.