Fragment 176-191 peptide is a short segment of human growth hormone (hGH) and is sometimes referred to as the “lipolytic fragment.” The name was coined due to research on animal systems which has proven that Fragment 176-191 enhances fat metabolism in genetically engineered obese mice. Human growth hormone (hGH) treatment has several adverse effects on the body, such as the suppression of carbohydrate metabolism, altered sensitivity towards insulin, the promotion of long bone growth, and heightened insulin-like growth factor-1(GF-1) levels. Extensive animal studies have shown that the synthetic fragment enhances the lipolytic effects of hGH without inducing the same side effects. Hence the peptide can be used for anti-obesity treatments.
Fragment 176-191 SPECIFICATIONS
AKA: Frag 176-191
Molecular Formula: C78H125N23O23S2
Molecular Weight: 1817.1 g/mol
CAS Number: 66004-57-7
Physiological effects of Frag 176-191
1. Burning of fat and Weight Loss
The fat-burning action of Fragment 176-191 peptide is brought about by increasing the production of beta-3 adrenergic receptors (3-AR or ADRB3). Agonist activity of the fragment upon interaction with ADRB3 directly enhances fat burning in adipose tissue and triggers thermogenesis in skeletal muscle. Genetically modified mice that lack ADRB3 are resistant to the effect of hGH / fragment 176-191.
Studies have shown treatment of fragment 176-191 causes up to 50% weight reduction in obese mice over three weeks. Interestingly, the peptide mediates weight reduction only in obese mice but not in lean mice during the same span of treatment. The results suggest that there are secondary pathways involved in energy homeostasis that are capable of maintaining fat reserve in lean mice by overriding ADRB3 pathway.
2. Decrease in Blood Sugar
The C terminal end of hGH principally has been observed to bring about hypoglycemic (low blood sugar) levels in mice’s bodies. Screening of at least six different fragments obtained from the C terminal section of hGH has shown that fragment 176-191 is the most effective synthetic derivative of hGH for decreasing blood sugar levels. The hypoglycemic function is secondary to maintaining an increased expression of insulin in blood plasma. These functions prove that the fragment has the potential to treat prediabetes and type-2 diabetes.
3. Promotion of Cartilage Regeneration
Among other beneficial effects of Fragment 176-191 is the ability of cartilage regeneration. An article published by a Korean group in 2015 revealed that synthetic peptides could bring about cartilage regeneration like hyaluronic acid treatment. Research in rabbits has highlighted that weekly injection of Fragment 176-191 improve cartilage growth (within laboratory measures) and its co-administration with hyaluronic acid (HA) is more effective. Fragment 176-191, both independently and in combination with HA helps to improve the conditions of osteoarthritis. Thus there is the scope of a better and more beneficial treatment involving this synthetic fragment which will overcome the requirement of surgery.
Safety Studies for frag 176-191
There is a concern regarding the administration of hGH or its derivatives for weight loss. This concern arises from the fact that hGH has shown that exogenous use over extended periods can have significant physiological side effects such as:
– Edema (swelling)
– Increased resistance to insulin
– Hypertension (high blood pressure)
The Journal of Endocrinology and Metabolism published a study in 2013 which evaluated six research works conducted on the rate and relevance of detrimental effects of Fragment 176-191 peptide. The study is based strictly on the work that has abided by the placebo-controlled, randomized, and double-blinded model of a phase IIb clinical trial with the aim to achieve the highest possible standards of evidence. The study has revealed that both intravenous and oral use of Fragment 176-191 shows no significant alterations compared to placebo control in:
– Physical findings
– Glucose levels
– Laboratory parameters
– Glucose tolerance
– IGF-1 levels
– Insulin sensitivity or
– Rates of adverse events (such as headaches).
The meta-analysis has highlighted that the peptide offers the beneficial effects of hGH treatment without triggering the harmful effects of hGH. The studies speak in favor of regulated use of the synthetic peptide in clinical settings apart from providing insight into the moderation of human growth and development, fat metabolism, and energy homeostasis by the peptide. The studies thus open doors for more comprehensive understanding of energy homeostasis and targeted fat metabolism and ways of manipulating it.
It is important to note that hGH influences muscle growth and development while Fragment 176-191 peptide is strictly catabolic in nature. It triggers lipolysis in adipocytes without bringing about acromegaly or other adverse situations associated with hGH use. Mice models have also shown that the peptide does not promote cellular proliferation.
Research on Fragment 176-191 peptide
The principal areas of research on Fragment 176-191 peptide explore its role in fat metabolism and weight loss. The findings have led to further research on the interesting domain of the mechanism of energy homeostasis in the body. The secondary areas of interest include the effect of Fragment 176-191 in the repair of cartilage and connective tissue regeneration.