Fig. 6

ER stress and UPR pathway are suppressed in the HF group. URP-related protein levels are significantly increased in the HF + NAC (1–12) group. a Western blot results for p-PERK, ATF4, HSP70, HSP60, and ClpP. Quantification of b p-PERK, c ATF4, d HSP70, e HSP60, and f ClpP expression. All values are expressed as mean ± SEM (n = 6). *P < 0.05. The letters represent different groups (CD for chow diet group; CD + NAC for chow diet and NAC intervention 1–12 months group; HF for high fat diet group; HF + NAC (1–6) for high fat diet and NAC intervention 1–6 months group; HF + NAC (1–12) for high fat diet and NAC intervention 1–12 months group)