Comparison of Effect of Oestrogen on Muscle Development of Male and Female Mice

Abstract

The effect of oestrogen on muscle development was determined in 8 muscles (biceps brachii, triceps brachii, common digital extensor, soleus, superficial digital flexor, cranial tibialis, gastrocnemius and long digital extensor muscles of sexually immature male and female mice. Each mouse was killed at a mature age of 16 weeks. The muscle development as determined by increase in muscle weight was significantly smaller in muscles of oestrogen-treated male and oestrogen-treated female mice as compared to the muscles of normal male and normal female mice. The muscles of normal male mice were very significantly larger than those of normal female mice. There was, on the other hand, no significant difference between the muscle mass of oestrogen-treated male and oestrogen-treated female mice. This indicated that the smaller muscle mass of normal female mice when compared to normal male mice was connected with inhibitory effect of oestrogen on the muscle development of female mice.

17β-Estradiol Represses Myogenic Differentiation by Increasing Ubiquitin-specific Peptidase 19 through Estrogen Receptor α

“…E2 replacement was found to reduce soleus muscle fiber size in 7-week-old ovariectomized female rats (34,35). Furthermore, estrogen injection was found to reduce soleus and gastrocnemius muscle weights of both sexes (36). Ovariectomy increases the incidence of small (Ͻ500 m 2 ) fibers, which is a morphological characteristic of newly formed myofibers, in soleus muscle, and E2 replacement diminishes this increase (37).…”

A rehabilitation exercise program to remediate skeletal muscle atrophy in an estrogen-deficient organism may be ineffective

“…There is now substantial evidence that E2 has an anabolic effect on skeletal muscle (Dobbs et al 2002;Fisher et al 1998;Greeves et al 1999;Ihemelandu 1981;Phillips et al 1993;Suzuki and Yamamuro 1985;Wiik et al 2008), including cells at the myoblast stage (Galuzzo et al 2009;Kahlert et al 1997;Thomas et al 2010;Tiidus et al 2005). Indeed, E2 deficient muscles with significantly lower force/ unit area demonstrated rescue of muscle force when E2 was given back to rats that were OVX (Moran et al 2006(Moran et al , 2007.…”

Expression of steroidogenic enzymes and synthesis of sex steroid hormones from DHEA in skeletal muscle of rats

“…Total tissue RNA was isolated using Isogen (Nippon Gene; Toyama, Japan), according to our previous studies (13). Total tissue RNA (2 g) was primed with 0.05 g of oligo d(pT) [12][13][14][15][16][17][18] and reverse transcribed by Omniscript reverse transcriptase using a cDNA synthesis kit (Qiagen) (15). The reaction was performed at 37°C for 60 min.…”

“…Testosterone and estradiol affect growth, strength, metabolism, and antioxidants in the skeletal muscle (16,17,35,39,40). Administration of testosterone has been reported to induce an increase in muscle strength with accretion of protein synthesis in the muscle (46).…”