The myokine decorin is regulated by contraction and involved in muscle hypertrophy

Roles of Exosome-Like Vesicles Released from Inflammatory C2C12 Myotubes: Regulation of Myocyte Differentiation and Myokine Expression

“…Our results are in agreement with previous studies [50,51] [27,28,52]. Consistently, our results clearly supported the contention that inflammation can lead to muscle atrophy, at least in part through the alteration of myokine expression; i.e., upregulation of myostatin associated with AMPK activation [41] and downregulation of counteracting decorin expression [27,28]. Therefore, although this cause-effect relationship should be clarified in further studies, the myogenic vs muscle atrophic effect of decorin and myostatin, respectively, may contribute to the inhibition of myogenesis by inflammation.…”

“…In the face of stress or damages, an appropriate positive balance between the proliferation and differentiation of myogenic satellite cells in muscle against the loss of myocytes maintains the structure and function of skeletal muscles [49]. Our results are in agreement with previous studies [50,51] [27,28,52]. Consistently, our results clearly supported the contention that inflammation can lead to muscle atrophy, at least in part through the alteration of myokine expression; i.e., upregulation of myostatin associated with AMPK activation [41] and downregulation of counteracting decorin expression [27,28].…”

“…Therefore, we hypothesized that inflammation alters myokine expression in skeletal muscle cells and that exosomes released from inflammatory muscle cells are responsible for suppressing muscle differentiation. Among myokines, in particular, it has been reported that decorin downregulates the activity of the anti-myogenic myostatin/Smad [25][26][27] and is associated with muscle regeneration [10], hypertrophy [28], and myogenic differentiation [29]. Therefore, we evaluated the effects of inflammation on the expression of decorin and myostatin and on the molecular switches of muscle differentiation using C2C12 myotubes.…”

Exercise and Regulation of Adipokine and Myokine Production

“…30 In addition, it was recently shown that decorin mRNA expression is enhanced in skeletal muscle after chronic exercise combining strength and endurance training. 34 A study by Heinemeier et al reported increased decorin mRNA expression in skeletal muscle following an acute endurance exercise, 35 and decorin plasma levels were increased after acute resistance exercise. 34 Another antagonist of proteins of the TGF-β superfamily is follistatinlike 1 (FSTL1) which is a secreted glycoprotein belonging to the follistatin family of proteins.…”

“…34 A study by Heinemeier et al reported increased decorin mRNA expression in skeletal muscle following an acute endurance exercise, 35 and decorin plasma levels were increased after acute resistance exercise. 34 Another antagonist of proteins of the TGF-β superfamily is follistatinlike 1 (FSTL1) which is a secreted glycoprotein belonging to the follistatin family of proteins. 36 Studies indicate that FSTL1 may have beneficial effects on ischemia-reperfusion injury in muscle and heart tissue associated with antiapoptosis.…”