IGF-1 REVIEW | IGF-1 For Sale
13December 13, 2019
IGF-1 REVIEW | IGF-1 For Sale
What is Insulin-like Growth Factor?
Insulin-like growth factor-1 (IGF1) is also known as somatomedin C and has a similar structure to insulin. It is a hormone that has been found to play a role in growth of young mammals and has anabolic effects on adult animals. IGF-1 not only reflects but also regulates growth hormone levels in the blood, emphasizing its critical role in growth and developmental processes. Additionally, IGF-1 is involved in growth hormone production, highlighting the hormonal balance crucial for human growth and development.
It is synthesized in the liver as an endocrine hormone and in target organs in a paracrine or autocrine way. It is produced all through life and highest levels during puberty in animals and lowest in infant and aged populations.
Structure of Insulin-like Growth Factor
It is a small peptide consisting of 70 amino acids with a molecular weight of 7649Da. IGF-1 has an alpha and beta chain that are linked by disulphide bonds. Rat IGF-1 is synthesized as four precursor isoforms with alternate N- and C-terminal propeptides. Mature IGF-1 is identical between isoforms and is generated by the cleavage of propetide terminals. The C-peptide region has 12 amino acids.
Mechanism of Action
Research with animal subjects have demonstrated that IGF-1 is a primary mediator of Growth Hormone effects. Growth hormone is produced by the pituitary gland and circulates in the blood stream to cause IGF-1 production by the liver.
IGF-1 binds to at least two cell membrane receptor tyrosine kinases which includes IGF-1 receptor and insulin receptor. Its main action occurs due to its binding with IGF-1 receptor which is ubiquitous among tissues. This ligand-receptor complex ignites intracellular messages through AKT signaling pathway which is known for its ability to promote cell growth and proliferation and its inhibition of programmed cell death. Growth hormones, like IGF-1, have complex roles in health, where increased levels may reduce life span in animal studies, but lower levels might promote longevity and reduce inflammatory responses.
Insulin can also bind to IGF-1 receptor but with much less affinity and IGF-1 can also bind to insulin receptor to produce actions at 10% of the potency insulin produces. Insulin Growth Factor-1 has been shown to interact with all 7 IGF-1 binding proteins especially IGFBP2, IGFBP5 and serum levels of these two is inversely proportional to circulating IGF-1.
Blood transported IGF-1 coordinates balanced growth across many tissues and organs. Stimulation of autocrine or paracrine IGF-1 can result in unbalanced growth since effects are exerted without the influence of growth hormone.
Insulin-like Growth Factor-1 Effects on Muscle Growth
The first demonstration of the effects of exogenous IGF-1 stimulates growth was with administration of purified hormone to rats that had their pituitary gland removed.
In rats with diabetes, it was found to help in glucose control and potency depended on duration of diabetes in an inverse manner.
Administration of IGF-1 in vivo showed anabolic effects with the subsequent rapid growth of neonatal rats but evidence suggests that nutritional sufficiency is necessary for full expression of the give dose.
Exogenous administration of IGF-1 induced hepatoprotective and antifibrinogenic actions in experimental liver cirrhosis. These effects were associated with a diminution of the hepatic contents of several factors involved in oxidative damage like myeloperoxidase and nitric oxide.
When brain ischemia was induced by right, middle cerebral artery occlusion, IGF-1 expression in central nervous system was significantly reduced. Intramuscular IGF-1 injection increased expression in affected muscles, sciatic nerve, lumbar spinal cord and motor cortex. This was decreased neuronal apoptosis and improved motor function.
Immunohistochemical analysis of rat testis at different ages revealed that the level of IGF-1 receptor increases from birth to 20 days postnatal life. Tests revealed that IGF-1 decreases the level of apoptosis in Leydig cells at all stages of development.
Higher levels of IGF-1 are associated with an increased likelihood of developing breast cancer. Studies involving large cohorts have demonstrated that women with IGF-1 concentrations in the upper percentile show a significantly elevated risk for breast cancer, particularly for estrogen receptor positive types.
IGF-1 promotes muscle growth, particularly in athletes and bodybuilders who seek its anabolic effects for strength enhancement and quicker recovery. However, there are concerns regarding the safety of IGF-1 supplementation, its potential for abuse in sports as a performance-enhancer, and the associated health risks.
Mechanism of Action of Insulin-like Growth Factor-1 (IGF-1)
Recombinant IGF produced by the bacteria E. coli is obtained via chromatographic techniques for research use. Human growth hormone stimulates the production of insulin-like growth factor-1 (IGF-1), which plays a significant role in growth stimulation and metabolic functions. Insulin like growth factors, including IGF-1 and IGF-2, are anabolic peptide hormones that mediate the effects of growth hormone, regulating growth and metabolism.
Insulin-like growth factor-1 can be purchased from Loti labs. It is necessary to use only USA made peptides to ensure optimal quality of your research. IGF-1 LR3 and IGF DES 1,3 produced and sold by Loti labs undergo top-notch quality control and are tested with high power liquid chromatography (HPLC) and mass spectrometry to make sure they are of the highest purity. IGF-1 is usually sold in 1mg vials.
IGF-1 and Growth Hormone
Relationship between GH and IGF-1
IGF-1 is closely linked to growth hormone (GH), as it is the primary mediator of GH’s effects on growth and development. GH stimulates the production of IGF-1 in the liver and other tissues, which in turn promotes cell growth and differentiation. The relationship between GH and IGF-1 is complex, with GH regulating IGF-1 production and IGF-1, in turn, regulating GH levels. This feedback loop ensures that growth and development occur in a controlled and coordinated manner.
GH and IGF-1 work together to promote normal growth during childhood and adolescence. GH stimulates the production of IGF-1, which then promotes the growth and development of bones, muscles, and other tissues. In adults, GH and IGF-1 continue to play important roles in maintaining muscle mass, bone density, and overall health.
Research has shown that GH and IGF-1 are also involved in regulating fetal development during pregnancy. GH produced by the placenta stimulates the production of IGF-1, which promotes the growth and development of the fetus. Abnormal levels of GH and IGF-1 during pregnancy have been linked to an increased risk of pregnancy complications and fetal growth restriction.
Animal studies have also demonstrated the importance of GH and IGF-1 in regulating postnatal body growth. GH stimulates the production of IGF-1, which promotes the growth and development of skeletal muscle and bone. Abnormal levels of GH and IGF-1 have been linked to an increased risk of growth disorders and other health problems.
In addition to its role in regulating growth and development, GH and IGF-1 have also been implicated in regulating insulin resistance and glucose metabolism. Research has shown that GH and IGF-1 can improve insulin sensitivity and glucose metabolism, which may have implications for the treatment of type 2 diabetes.
Overall, the relationship between GH and IGF-1 is complex and multifaceted, with both hormones playing important roles in regulating growth, development, and metabolism.
IGF-1 and Nutrition
Foods that May Lower IGF-1
While there is limited research on the specific foods that may lower IGF-1 levels, some studies suggest that certain nutrients and dietary patterns may have an impact on IGF-1 production. Here are some foods and nutrients that may potentially lower IGF-1 levels:
Green Tea: Green tea contains polyphenols, which have been shown to reduce IGF-1 levels in animal studies. These antioxidants may help modulate the body’s production of growth factors, including IGF-1.
Lycopene: Lycopene, an antioxidant found in tomatoes and other fruits, has been shown to reduce IGF-1 levels in some studies. This compound may help in regulating cell growth and reducing the risk of certain cancers.
Alcohol: Moderate alcohol consumption has been linked to lower IGF-1 levels in some studies. However, it is essential to balance alcohol intake with overall health considerations.
Low-Calorie Diets: Calorie restriction has been shown to reduce IGF-1 levels in animal studies. This dietary approach may help in promoting longevity and reducing the risk of age-related diseases.
Low-Protein Diets: Reducing protein intake may also lower IGF-1 levels, as protein is a key stimulator of IGF-1 production. This approach may be beneficial in certain health conditions where lower IGF-1 levels are desired.
It is essential to note that the evidence for these foods and nutrients is limited, and more research is needed to confirm their effects on IGF-1 levels. As always, it is crucial to consult with a healthcare professional before making significant changes to your diet.
References
Chang et al. 2004: Expression of liver insulin-like growth factor-1 and its serum level in rats with diabetes.
Garcia-Fernandez et al. (2005): Antioxidant effects of insulin-like growth factor-1 in rats with advanced liver cirrhosis.
Werner et al. (2008): Similarities and differences between insulin and IGF-1 structures, receptors, and signaling pathways.
Denley et al. (2005): Molecular interactions of the IGF system. Cytokine Growth Factor Rev.
Nurten et al. (2016): Efffect of insulin-like growth factor-1 on random pattern skin flap survival in rats.
