Sandwich ELISA, Biotin-labelled antibody
Store the kit at 2–8°C. Under these conditions, the kit is stable until the expiration date (see label on the box).
0.16 – 10 ng/ml
Limit of Detection
n = 8, CV = 2.5%
n = 6, CV = 9.5%
- It is intended for research use only
- The assay time is less than 3.5 hours
- The kit measures total Myostatin Latent Complex and free Myostatin Prodomain in serum and plasma (EDTA, citrate, heparin)
- Assay format is 96 wells
- Quality Controls are human serum based
- Standard is recombinant protein based
- Components of the kit are provided ready to use, concentrated or lyophilized
Cardiovascular disease, Energy metabolism and body weight regulation, Muscle growth and physiology regulation, Pulmonary diseases
Myostatin, also known as growth and differentiation factor 8 (GDF-8), belongs to the transforming growth factor β (TGF-β) superfamily of structurally related growth factors. Myostatin plays an essential role in regulating skeletal muscle growth and differentiation of tissues throughout the body and this function appears to be conserved across species.
Myostatin is expressed in human skeletal muscle as a biologically-inactive precursor protein (pre-promyostatin) consisting of an N-terminal signal peptide (23 amino acid residues), a propeptide domain (myostatin prodomain) which contains 243 amino acid residues, and a C-terminal domain containing 113 amino acids. Precursor protein (pre-promyostatin) forms a homodimer before proteolytic processing. After removal of the signal peptide, a furin protein convertase cleaves the promyostatin to generate myostatin propeptide and biologically active 12 kDa mature glycoprotein myostatin. The cleaved propeptide molecules remain non-covalently disulfide-linked to the mature C-terminal dimer forming the Latent Complex.
The native myostatin circulates in serum as a part of the latent complex. Follistatin-related gene (FLRG) product has been reported to be an additional protein bound to circulating myostatin. The myostatin propeptide is known to bind and inhibit myostatin in vitro. This interaction is relevant in vivo, with a majority (>70%) of myostatin in serum being bound to its propeptide. Two molecules of myostatin propeptide inhibit the biological activity of one GDF-8 homodimer.
Overexpression of GDF-8 propeptide, follistatin or activin type II results in enhanced muscle development and increased skeletal muscle growth. It has been shown that GDF-8 propeptide inhibits specific GDF-8 binding to L6 myoblast cells. Myostatin mutation was found in a child with muscle hypertrophy which provides strong evidence that myostatin plays a significant role in regulating muscle mass in humans. Myostatin promotes differentiation of multipotent mesenchymal cells into the adipogenic lineage and inhibits myogenesis. Studies have shown that myostatin could play an important role in cardiac development and physiology and has regulatory roles in fat metabolism. Myostatin is expressed in myocardium where it exerts anti-hypertrophic, but profibrotic, effects. Circulating and local myostatin is elevated in chronic heart failure and is an important player in cardiac cachexia. GDF-8 as a negative regulator of skeletal muscle mass has been implicated in several diseases involved in muscle wasting and cachexia. Circulating myostatin levels in male patients are elevated in chronic obstructive pulmonary disease (COPD) and the elevated myostatin levels are negatively correlated with total body skeletal muscle mass. Myostatin not only regulates the growth of myocytes but also directly regulates muscle fibroblasts. Myostatin stimulates proliferation of muscle fibroblasts and production of extracellular matrix proteins both in vitro and in vivo. GDF-8 itself or molecules that inhibit GDF-8 signalling may prove useful in the treatment of musculodegenerative states such as muscular dystrophy, neuromuscular diseases or cancer cachexia. Myostatin blockade offers a strategy for reversing muscle wasting in Duchenne's muscular dystrophy (DMD) without resorting to genetic manipulation. Latent TGFβ binding protein 4 (LTBP4) was identified as a genetic modifier of muscular dystrophy. It has been shown that myostatin forms a complex with LTBPand that overexpression of LTBP4 led to a decrease in myostatin levels. LTBP4 also interacts with TGFβ and GDF11, a protein highly related to myostatin. These data identify LTBP4 as a multi-TGFβ family ligand binding protein with the capacity to modify muscle disease through overexpression.
Serum and intramuscular concentrations of myostatin-immunoreactive protein are increased in HIV-infected men with weight loss compared with healthy men and correlate inversely with fat-free mass index. It has been demonstrated that increased expression of the myostatin gene is associated with weight loss in men with AIDS wasting syndrome.