Effect of Natural Menopause and Hormone Therapy on Markers of Cellular Senescence

Background Accumulation of senescent cells and the release of proteins from those cells contribute to aging‐related disorders. Estrogen may reduce physiological changes associated with aging through inhibition of cell senescence. This study aimed to determine the effects of menopausal hormone treatments on circulating levels of cell senescence markers. Methods GDF 15, TNF R1, FAS, and MIP1α were measured in serum using bead‐based assays and compared among women who were within 3 years of natural menopause (mean age 52 years) participating in the Kronos Early Estrogen Prevention Study (KEEPS). Women were randomized to either placebo (n=38), oral conjugated equine estrogen (oCEE, n=37), or transdermal 17β‐estradiol (tE2, n=34). Serum levels of the senescent markers for each treatment group were compared to placebo 36 months after randomization using the Wilcoxon rank‐sum test. Results Serum levels of GDF 15, TNF R1, and FAS but not MIP1α were lower in both the oCEE and tE2 groups compared to placebo. However, the difference in levels between treatment and placebo were greater for oCEE [−108 pg/mL (p=0.008), −234 pg/mL (p=0.0006), and −1374 pg/mL (p<.0001), respectively] than for tE2 [−76 pg/mL (p=0.072), −105 pg/mL (p=0.076), and −695 pg/mL (p=0.036), respectively]. Conclusions In recently menopausal women, oCEE and tE2 reduced circulating levels of some markers of cell senescence. Differences in the magnitude of effect may reflect the differences in circulating levels of 17β estradiol, estrone, and sulfonated estrogens between the two active treatments. Support or Funding Information The research is supported by the Kronos Early Estrogen Prevention Study, NIA U54‐AG44170, and the Mayo Fnd.