Figure 4.

Melatonin-mediated antisenescence effect was via MT1 and MT2 membrane receptors. To investigate the role of melatonin receptors, OVX BMMSCs were pretreated with 10 μM of luzindole and 10 μM of 4-phenyl-2-propionamidotetralin (4-P-PDOT), respectively, and then treated with H₂O₂ (100 μM) for 2 h and melatonin (MT, 100 μM) for an additional 72 h. (a) The mRNA expression levels of Sirt1, P16, P21, and P53 were quantified using real-time qRT-PCR. (b–d) The protein levels of MT1, MT2, p-AMPK, AMPK, SIRT1, P16, P21, and P53 were determined using Western blot assays. Values are presented as the mean ± S.E.M of four independent experiments (n = 4) in qRT-PCR experiments and three independent experiments (n = 3) in Western blot assays. Statistically significant differences are indicated by ^∗p < 0.05 or ^∗∗p < 0.01 between the indicated groups; ^#p < 0.05 or ^##p < 0.01 versus the control (CTRL) group.