Estrogen modulates exercise endurance along with mitochondrial uncoupling protein 3 downregulation in skeletal muscle of female mice

17β‐Estradiol reduces mitochondrial cAMP content and cytochrome oxidase activity in a phosphodiesterase 2‐dependent manner

“…Though this effect may be due to reduced cytochrome oxidase activity, other factors may also affect mitochondrial membrane potential, for example, upregulated expression of mitochondrial uncoupling proteins. However, several studies have suggested a down-regulation of these proteins by estradiol in muscle cells (Alexanderson et al, 2009;Nagai et al, 2016).…”

Estrogen signaling increases nuclear receptor subfamily 4 group A member 1 expression and energy production in skeletal muscle cells

“…Accumulating evidence implies that estrogen signaling may directly contribute to the maintenance of muscle strength and/or volume, although the precise mechanisms remain to be elucidated. We previously showed that estrogen deficiency in female mice decreased exercise endurance, and the administration of estrogen to ovariectomized (OVX) mice reversed this phenomenon [6]. In that study, the skeletal muscle mass of OVX mice, however, was not substantially different from that of control mice.…”

“…When the cells reached confluence, the medium was switched to high-glucose DMEM supplemented with 2% horse serum and penicillin/streptomycin (differentiation medium) to induce C2C12 myotubes for 7 days and replaced with the fresh differentiation medium every 2 days. Infection of differentiated myoblastic C2C12 cells with Ad-caERα or fluorescent protein DsRed (Ad-DsRed) at m.o.i.30 (n = 3 for each group) was performed as described previously [6,7]. Then, cells were treated with 1 μM ICI 182,780 (ICI) (Nacalai tesque, Kyoto, Japan) or vehicle for 48 h. Prior to estrogen treatment (10 nM 17β-estradiol (E2) (Sigma-Aldrich, St. Louis, MO, USA)), cells were maintained in phenol red-free DMEM containing 2% dextrancoated charcoal-stripped serum for 48 h and treated with combination of 1 μM ICI and 10 μg/mL puromycin (Sigma-Aldrich, St. Louis, MO, USA) for 4 h (n = 3 for each group) [13].…”

“…Differentiated myoblastic C2C12 cells on 24-well plates were transfected with an estrogen response element (ERE)-driven firefly luciferase reporter, ERE-tk-Luc (0.4 μg) [7] and a control Renilla luciferase reporter, pRL-CMV (0.1 μg) (Promega, Madison, WI), in phenol red-free DMEM containing 2% dextran-coated charcoalstripped serum using Lipofectamine 2000 transfection reagent (Invitrogen, Carlsbad, CA, USA) for 24 h. After transfection, medium was removed and cells were infected with Ad-caERα or Ad-DsRed at m.o.i. 30 for 24 h as described previously [6,7]. Then, cells were treated with or without 10 nM E2 (Sigma-Aldrich, St. Louis, MO, USA) or 1 μM ICI for 24 h and luciferase assay was performed (n = 3 for each group).…”

“…We performed a microarray analysis on mouse soleus muscle and found that the expression levels of Ucp3 were upreg-ulated by OVX whereas they were downregulated by estrogen administration. Downregulated Ucp3 along with an increase in cellular ATP content was also observed in differentiated myoblastic mouse C2C12 cells adenovirally transduced with constitutively active estrogen receptor α (Ad-caERα) [6,7].…”