Treatment of frail hypogonadal men with testosterone, therefore, can result in changes in muscle gene expression, increased muscle mass, improvements in strength, power and endurance and improved physical function.
While cyclic strain reduced both vimentin and alpha-smooth muscle actin compared to unstrained controls, vimentin and alpha-smooth muscle actin expression increased with strain anisotropy and correlated with direction (P < 0.05).
TNF-alpha muscle gene expression was not different between treated and untreated mice while IL-10 muscle gene expression increased.
Skeletal muscle ADIPOR1 expression increased approximately threefold (p < 0.05) in obese participants compared with lean controls, although type 2 diabetic patients did not differ from lean control individuals (Fig. 3b).
In gastrocnemius/plantaris muscles, MuRF1 expression increased 21-fold and 24-fold after 24 hours and 48 hours of starvation, respectively (P <0.01 for both).
In the capillaries collected from the gastrocnemius muscle VEGF-A expression increased significantly in HE6 compared to C (Fig. 3a).
Skeletal muscle ADIPOR1 and ADIPOR2 expression increased approximately twofold (p < 0.05), while APPL1 expression decreased by approximately 50% (p < 0.05) following weight loss (Fig. 4).
Analysis in EDL and soleus, respectively, a glycolytic and an oxidative muscle, showed that Drp1 expression increased in the mitochondrial protein fraction.
The fibroblasts involved in scarring have a myofibroblast phenotype characterised by α-smooth muscle actin (α-SMA) expression, increased secretion of collagen type I and III, and contractility [ 30].
This is further substantiated by a study that TNF-α expression was lower in muscle-specific PGC-1α knockout mice, and TNF-α expression increased in muscle-specific PGC-1α overexpression mice compared with littermate WT mice [ 39].
