TGF-β and myostatin expression.

<p>(a) Cultured myoblasts incubated with DMEM and supplemented with decorin 10 ng/ml, decorin 25 ng/ml, 10% PRP exudate and 20% PRP exudate (ELISA). Cytokine expression was measured after 48 hours of incubation. (b): TGF-β expression. (c): MSTN expression. Three independent tests were performed and the results were expressed by the absolute absorbance values (in grey) and mean ratios (%, ± SD) of absorbance in treated wells to those in control wells (in blue). ANOVA, p<0.001 compared with control, *p<0.005 compared with decorin. In PRP group, no cells were growing in the well in order to determine the TGF-β content in PRP.</p

Myoblast proliferation rate.

<p>The figure shows the proliferation of myoblasts after 7 days of incubation with DMEM supplemented with decorin 10 ng/ml, decorin 25 ng/ml, 10% PRP exudate and 20% PRP exudate. Three independent tests were performed and the results are expressed by the absolute absorbance values (in blue) and mean ratios (%, ± SD) of absorbance in treated wells to those in control wells (in grey). ANOVA, *p<0.001 compared with control.</p

Desmin expressing myotubules.

<p>Immunofluorescence staining for merged stained nuclei (blue), α-tubulin (red), and desmin (green). Three independent tests were performed and the results are expressed by the mean values of “Selective color” pixel count (in grey) and mean ratios (%, ± SD) of pixel count in the treated group to those in control groups (in blue). ANOVA, * p<0.01, ** p<0.005 compared with the control. (a) control, (b) decorin-treated group, (c) PRP-treated group, (d) PRP and decorin-treated group. Evident differences can be seen in the polynucleated myotubules count and in desmin expression among the control and PRP and/or decorin treated groups. Scale bar = 200 μm.</p

Myogenic differentiation of hMC.

<p>Each sample consisted of 5,000 cells that were hierarchically gated according to the expression of specific markers (top right). Top left: Aspect ratio versus cell area gated on a bivariate plot in order to isolate single cells; middle left: subgroup of previously gated cells in focal plane positive with CD56 surface marker selected using a two-dimensional plot of image contrast versus root-mean-squared (rms) gradient; bottom left: presence of MyoD and/or myogenin exclusively in CD56 positive cells by measuring the intensity of each probe. Bottom right: Results are expressed as percentage ratios between cells positive only for CD56, those additionally positive for MyoD and those expressing also myogenin or myogenin alone in each treated as well as each untreated population of cells. Scale bar = 50 μm.</p

MTT assay.

<p>Three independent tests were performed and the results were expressed by the mean ratios (%, ± SD) of absorbance in treated wells to those in control wells. ANOVA, *p<0.001, **p<0.05 compared to control.</p

TGF-β and MSTN expression (ELISA).

<p>Three independent tests were performed for each cytokine and the results are expressed by the mean ratios (%) of absorbance in treated wells to those in control wells. ANOVA, p<0.001 compared to control.</p

Schematic representation of muscle regeneration on the regulatory level.

<p>During skeletal muscle regeneration various MRFs are being expressed (in blue). Satellite cells differentiate into myoblasts which proliferate and either further differentiate into polynucleated myotubules or transform into myofibroblasts. TGF-β and MSTN play an important role in inhibiting/stimulating these steps (marked with +/- symbols).</p