Fig. 2.

The ubiquitin-proteasome pathway in skeletal muscle of the experimental groups. a Atrogin-1, b MuRF1, c MUSA1, d C5 subunit and e C2 subunit mRNA levels, and f 26S chymotrypsin-like proteasome activity. Results are presented as the mean ± SD, n = 6 per group. Mean value was significantly different from that of the sham group: *P < 0.05, **P < 0.01. Mean value was significantly different from that of the NPD group: †P < 0.05, ††P < 0.01. Mean value was significantly different from that of the LPD group: ‡P < 0.05. Sham, normal-protein diet; NPD, normal-protein diet; LPD, low-protein diet; LPD + KA, low-protein diet supplemented with ketoacids