Figure 4: Resveratrol reduces matrix metalloproteinases (MMPs) in skeletal muscles of obesity-induced sarcopenia mice, but elevates MMPs in age-related sarcopenia senescence-accelerated mouse prone 8 (SAMP8) mice. (a and b) The levels of MMP2, MMP9, ANP, and BNP protein in HFD-induced obesity mice were measured by Western blotting. All data were expressed as mean ± standard error of the mean (SEM). *P < 0.05, **P < 0.01, compared with control.#P < 0.05, compared with HFD control mice without treatment. α-tubulin was used as a loading control. (c and d) Western blot analysis of MMP2, MMP9, FGF-2, and UPA in SAMP8 mice. α-tubulin was used as a loading control. Quantification of Western blot bands was made by densitometry. All data were expressed as mean ± SEM. *P < 0.05, **P < 0.01, compared with SAMP8 control group. HFD: High-fat diet, LR: Low-dose resveratrol, MR: Middle-dose resveratrol, HR: High-dose resveratrol, ANP: Atrial natriuretic peptide, BNP: Brain natriuretic peptide, FGF: Fibroblast growth factor, UPA: Urokinase-type plasminogen activator, NS: No significant difference, SAMP8+Ex; Exercise training SAMP8 groups, SAMP8+Re: Resveratrol SAMP8 groups, SAMP8+Ex+Re: Combination of exercise training and resveratrol intake SAMP8 groups.