Research Article

Local Overexpression of V1a-Vasopressin Receptor Enhances Regeneration in Tumor Necrosis Factor-Induced Muscle Atrophy

Figure 6

V1aR overexpression induces muscle regeneration even in the presence of TNF. Real-time PCR analysis shows that forced expression of TNF significantly increases the expression of Pax7 (a) and desmin (b) compared with mock-transfected samples. The expression level of these markers is even higher in muscle overexpressing TNF and V1aR together, while only a slight, yet significant, increase is observed in V1aR-transfected muscle. Interestingly, myogenin expression (c) does not significantly change in the presence of TNF, while it is strongly upregulated in V1aR overexpressing muscles, both in the presence and in the absence of TNF. (d) Western blot analysis shows a downregulation of MHC expression by TNF, while its expression increases in V1aR and V1aR+TNF overexpressing muscles. (e) Densitometric analysis of three independent experiments for MHC versus tubulin expression. ; ; by Student’s -test. (f) Immunofluorescence analysis of embryonic MHC in TA cross-sections. Muscles overexpressing both TNF and V1aR display an increase in number and size of regenerating muscle fibers compared with TNF overexpressing muscle.
235426.fig.006a
(a)
235426.fig.006b
(b)
235426.fig.006c
(c)
235426.fig.006d
(d)
235426.fig.006e
(e)
235426.fig.006f
(f)