The body weight and WAT weight in aging M4–/– mice. (A) and (B) Changes in the body weight in male mice. *P < .05 for WT vs M4–/– mice. (C, D) Changes in the body weight in female mice. (E) Changes in the body weight in male mice at the age of 20 weeks. **P < .01, ***P < .001 for WT vs M1–/–, M3–/–, M4–/–, or M5–/– mice. (F, G) Epididymal adipose tissue in male M4–/– mice at the age of 20 weeks. (H, I) Subcutaneous adipose tissue in male M4–/– mice at the age of 20 weeks. (J) Mesentery adipose tissue in male M4–/– mice at the age of 20 weeks. (K) Weekly food intake of male M4–/– mice from 8 weeks to 20 weeks of age. (L) Average weekly food intake of male M4–/– mice over the experimental period. (M, N) Body weight of WT and M4–/– mice during the feeding of a high-fat diet (HFD). All data are expressed as the mean ± SD. Data were analyzed using a 2-tailed Student's t-test. *P < .05, **P < .01, ***P < .001.