Hyaluronic acid, HAS1, and HAS2 are significantly upregulated during muscle hypertrophy

Abstract

Hyaluronic acid (HA) is a component of the extracellular matrix (ECM) in most vertebrate tissues and is thought to play a significant role during development, wound healing, and regeneration. In vitro studies have shown that HA enhances muscle progenitor cell recruitment and inhibits premature myotube fusion, implicating a role for this glycosaminoglycan in functional repair. However, the spatiotemporal distribution of HA during muscle growth and repair was unknown. We hypothesized that inducing hypertrophy via synergist ablation would increase the expression of HA and the HA synthases (HAS1-HAS3). We found that HA and HAS1-HAS3 were significantly upregulated within the plantaris muscle in response to Achilles tenectomy. HA concentration significantly increased 2.8-fold after 2 days but decreased towards levels comparable to age-matched controls by 14 days. Using immunohistochemistry, we found the colocalization of HAS1-HAS3 with macrophages, blood vessel epithelia, and fibroblasts varied in response to time and/or tenectomy. At the level of gene expression, only HAS1 and HAS2 significantly increased with respect to both time and tenectomy. The profiles of additional genes that influence ECM composition during muscle repair, tenascin-C, type I collagen, the HA-degrading hyaluronidases (Hyal) and matrix metalloproteinases (MMP) were also investigated. Hyal1 and Hyal2 were highly expressed in skeletal muscle but did not change after tenectomy; however, indicators of hypertrophy, MMP-2 and MMP-14, were significantly upregulated from 2 to 14 days. These results indicate that HA levels dynamically change in response to a hypertrophic stimulus and various cells may participate in this mechanism of skeletal muscle adaptation.

Hyaluronan Synthesis and Myogenesis

“…three HAS proteins are expressed by myoblasts in skeletal muscle (25), but the consistent relationship observed herein between increased Has2 transcript expression and myogenesis both in vivo and in vitro suggested that Has2 is intimately involved in the process by which myoblasts differentiate and fuse to form syncytial muscle cells. To test this hypothesis, we performed Has2 knockdown in C2C12 myoblasts that were induced to differentiate.…”

“…Has2 upregulation occurs neonatally, prior to detection of hypertrophy, suggesting that Has2 could be associated with the cause of hypertrophy in Callipyge muscles. Very recent studies have also reported increases in hyaluronan synthesis in a model of compensatory hypertrophy (25). Increased expression of Has1 and Has2 mRNAs was observed in this synergistic ablation model of hypertrophy, supporting the possibility of HAS2 mediating muscle growth and hypertrophy.…”

Periostin Induces Intracellular Cross-talk between Kinases and Hyaluronan in Atrioventricular Valvulogenesis

“…Real time PCR amplification reaction mixture (25 l) contained 12.5 l of 2ϫ SYBR Green PCR master mix following the Bio-Rad protocol, 5 l of diluted RT product (1:20), and 0.5 M sense and antisense primer sets. The primer sequences of Has1/2/3 (29), and GAPDH (30) are as follows: Col1␣1 (m), forward, 5Ј-gagccctcgcttccgtactc-3Ј, and reverse, 5Ј-tgttccctactcagccgtctgt-3Ј; Has1 (m), forward, 5Ј-gaggcctggtacaaccaaaag-3Ј, and reverse, 5Ј-ctcaaccaacgaaggaaggag-3Ј; Has2 (m), forward, 5Ј-gagcaccaaggttctgcttc-3Ј, and reverse, 5Ј-ctctccatacggcgagagtc-3Ј; Has3 (m) forward, 5Ј-tggacccagcctgcaccattg-3Ј, and reverse, 5Ј-cccgctccacgttgaaagccat-3Ј; GAPDH (m), forward, 5Ј-tgtcatcatacttggcaggtttct-3Ј, and reverse, 5Ј-catggccttccgtgttccta-3Ј.…”

Expression of MMP-1, -2, and -8 in longissimus dorsi muscle and their relationship with meat quality traits in cattle

“…Many studies have demonstrated that both the MMP-1 (Wang et al, 2009) and the MMP-2 (Zimowska et al, 2008) have important effects on the migration and differentiation of skeletal muscle satellite cells both in in vitro cultured muscle cells and in in vivo animal models, including mdx mice (an X-link dystrophic skeletal muscle mouse model). Deletion of the MMP-2 gene significantly decreased the extent of hypertrophy observed in MMP-2 knockout mice (Zhang et al, 2014) and an up-regulation of MMP-2 following a hypertrophic stimulus (Calve et al, 2012). This suggests that MMP-2 is a pertinent contributor to muscle hypertrophy.…”