(a) 17‐α‐estradiol (17aE2) is a relatively “non‐feminizing” estrogen which shows reduced activation of classical estrogen receptors compared with 17‐β‐estradiol (Anstead et al., 1997). Harrison et al. (2014) reported that in UM‐HET3 mice fed 4.8 mg 17aE2/kg (4.8 ppm) diet from 10 months of age, median male lifespans increased 12% (p = 0.0012, pooled across the three sites), while 17aE2 did not alter female lifespan. Strong et al. (2016) showed that using a threefold higher dose (14.4 ppm) from 10 months of age, pooled median male lifespans increased 19% (p < 0.001); the 90% lifespan increased 12%, but females still did not benefit. Thus, only males were tested in the present study. To determine whether 17aE2 treatment is effective when initiated in older mice, males were treated beginning at 16 or 20 months of age, choosing middle age, and early old age before many natural deaths.
I feel like it’s crazy that I inject estrogen but I’m going in for 24mcg estradiol valerate daily bloodwork on Monday. I don’t think it moved my e2 level much. I think I still have low e symptoms. But before I change dosage I must know for sure. I’m testing trough and 5 hours after injection to see if there is any fluctuation with such a tiny dose of the valerate ester. Valerate has a shorter half life than enanthate but longer half life that propionate.