Communication between muscles and brain via hormones (myokines).
Anyone know of any research into this and the possible training implications?
http://www.ncbi.nlm.nih.gov/...articles/PMC3609091/
http://jeb.biologists.org/content/214/2/337.full
".......sought a link between muscle contraction and changes in peripheral organs in the form of an ‘exercise factor’, which could be released from skeletal muscle during contraction and mediate some of the exercise-induced metabolic changes in other organs such as the liver and the adipose tissue. The idea that signalling pathways from contracting muscles to other organs are not solely mediated via the nervous system was supported by findings from electrical stimulation of paralysed muscles in spinal cord-injured patients (Kjaer et al., 1996).
It was obvious that one or more muscle-derived humoral factors existed. For lack of more exact knowledge, these humoral factors were called the ‘work stimulus’ or the ‘work factor’. In this context, our identification of muscle as a cytokine-producing organ was a breakthrough. In the year 2000, it became clear that contracting human skeletal muscle releases significant amounts of interleukin (IL)-6 into the circulation during prolonged single-limb exercise (Steensberg et al., 2000). Research during subsequent years highlighted the fact that muscle-derived IL-6 is an important player in metabolism (Pedersen and Febbraio, 2008). Today, it appears that skeletal muscle has the capacity to express several myokines (Pedersen and Febbraio, 2008). Thus, although the idea of an exercise factor can be traced back many years, our identification of muscle as a myokine-producing organ opens a whole new field of research."
http://www.oalib.com/...3028375#.VZg0TXCkqrU
Proteins secreted by skeletal muscle, so called myokines, have been shown to affect muscle physiology and additionally exert systemic effects on other tissues and organs. Although recent profiling studies have identified numerous myokines, the amount of overlap from these studies indicates that the secretome of skeletal muscle is still incompletely characterized. One limitation of the models used is the lack of contraction, a central characteristic of muscle cells. Here we aimed to characterize the secretome of primary human myotubes by cytokine antibody arrays and to identify myokines regulated by contraction, which was induced by electrical pulse stimulation (EPS). In this study, we validated the regulation and release of two selected myokines, namely pigment epithelium derived factor (PEDF) and dipeptidyl peptidase 4 (DPP4), which were recently described as adipokines. This study reveals that both factors, DPP4 and PEDF, are secreted by primary human myotubes. PEDF is a contraction-regulated myokine, although PEDF serum levels from healthy young men decrease after 60 min cycling at VO2max of 70%. Most interestingly, we identified 52 novel myokines which have not been described before to be secreted by skeletal muscle cells. For 48 myokines we show that their release is regulated by contractile activity. This profiling study of the human skeletal muscle secretome expands the number of myokines, identifies novel contraction-regulated myokines and underlines the overlap between proteins which are adipokines as well as myokines.
http://www.ncbi.nlm.nih.gov/pubmed/9762476
Hormone responses to exercise load are superior in indicating heavy training-induced stress when compared with resting hormone levels. These responses indicated decreased sympathoadrenal and/or adrenocortical activity (or exhaustion of the adrenal gland or the central nervous system). Individual hormonal profiles are needed to follow up training effects. Marked individual differences were found in training- and overtraining-induced hormonal changes.
PMID: 9762476 [PubMed - indexed for MEDLINE]
Anyone know of any research into this and the possible training implications?
http://www.ncbi.nlm.nih.gov/...articles/PMC3609091/
http://jeb.biologists.org/content/214/2/337.full
".......sought a link between muscle contraction and changes in peripheral organs in the form of an ‘exercise factor’, which could be released from skeletal muscle during contraction and mediate some of the exercise-induced metabolic changes in other organs such as the liver and the adipose tissue. The idea that signalling pathways from contracting muscles to other organs are not solely mediated via the nervous system was supported by findings from electrical stimulation of paralysed muscles in spinal cord-injured patients (Kjaer et al., 1996).
It was obvious that one or more muscle-derived humoral factors existed. For lack of more exact knowledge, these humoral factors were called the ‘work stimulus’ or the ‘work factor’. In this context, our identification of muscle as a cytokine-producing organ was a breakthrough. In the year 2000, it became clear that contracting human skeletal muscle releases significant amounts of interleukin (IL)-6 into the circulation during prolonged single-limb exercise (Steensberg et al., 2000). Research during subsequent years highlighted the fact that muscle-derived IL-6 is an important player in metabolism (Pedersen and Febbraio, 2008). Today, it appears that skeletal muscle has the capacity to express several myokines (Pedersen and Febbraio, 2008). Thus, although the idea of an exercise factor can be traced back many years, our identification of muscle as a myokine-producing organ opens a whole new field of research."
http://www.oalib.com/...3028375#.VZg0TXCkqrU
Proteins secreted by skeletal muscle, so called myokines, have been shown to affect muscle physiology and additionally exert systemic effects on other tissues and organs. Although recent profiling studies have identified numerous myokines, the amount of overlap from these studies indicates that the secretome of skeletal muscle is still incompletely characterized. One limitation of the models used is the lack of contraction, a central characteristic of muscle cells. Here we aimed to characterize the secretome of primary human myotubes by cytokine antibody arrays and to identify myokines regulated by contraction, which was induced by electrical pulse stimulation (EPS). In this study, we validated the regulation and release of two selected myokines, namely pigment epithelium derived factor (PEDF) and dipeptidyl peptidase 4 (DPP4), which were recently described as adipokines. This study reveals that both factors, DPP4 and PEDF, are secreted by primary human myotubes. PEDF is a contraction-regulated myokine, although PEDF serum levels from healthy young men decrease after 60 min cycling at VO2max of 70%. Most interestingly, we identified 52 novel myokines which have not been described before to be secreted by skeletal muscle cells. For 48 myokines we show that their release is regulated by contractile activity. This profiling study of the human skeletal muscle secretome expands the number of myokines, identifies novel contraction-regulated myokines and underlines the overlap between proteins which are adipokines as well as myokines.
http://www.ncbi.nlm.nih.gov/pubmed/9762476
Hormone responses to exercise load are superior in indicating heavy training-induced stress when compared with resting hormone levels. These responses indicated decreased sympathoadrenal and/or adrenocortical activity (or exhaustion of the adrenal gland or the central nervous system). Individual hormonal profiles are needed to follow up training effects. Marked individual differences were found in training- and overtraining-induced hormonal changes.
PMID: 9762476 [PubMed - indexed for MEDLINE]