Elevated collagen levels in skeletal muscles in SGCA- and SGCD-null mice and in the heart of SGCD-null mice.

<p><b>(a)</b> Immunofluorescent images of skeletal muscles stained with collagen type I (fibrotic marker, green) and laminin (extracellular matrix of muscle fibres, red) Scale bar: 100 μm. <b>(b)</b> Quantification of collagen type I positive area in skeletal muscles relative to wild type muscles. A significant increase in the percentage of collagen type I positive area was found in diaphragm and quadriceps muscles of SGCA- and SGCD-null mice, while no difference was found in the gastrocnemius. Tibialis anterior muscles of female SGCD-null mice showed a significant increase in collagen type I positive area compared to wild type. <b>(c)</b> Fibrotic and inflammatory gene expression measured by qPCR, normalized to <i>Gapdh</i> (n = 5 mice per group) in skeletal muscles of LGMD and wild type mice. A significant increase in <i>Col1a1</i> and <i>Cd68</i> expression was found in SGCA- and SGCD-null muscles when compared to wild type muscles. <b>(d)</b> Immunofluorescence images of the heart stained with collagen type I (fibrotic marker, green). Scale bar: 1000 μm. <b>(e)</b> The percentage of collagen type I positive area, measured with Image J was significantly increased in SGCD-null mice compared to wild type mice; males showed a significantly higher increase in collagen than did female SGCD-null mice. Q, quadriceps; GC, gastrocnemius; TA, tibialis anterior; Dia, diaphragm. * Indicates a significant difference from WT controls. # Indicates a significant difference from female SGCD-null mice. Error bars represent ± SD.