The short version of IGF-1 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-11-11. Anything still debated is marked as such rather than presented as settled.
Clinical interest in tesamorelin arose from the need to address visceral adiposity in people living with HIV. Antiretroviral therapy improved survival but was associated in some patients with central fat accumulation, altered lipid profiles, and metabolic complications. This condition, often called HIV-associated lipodystrophy, involves excess visceral adipose tissue that is difficult to manage through diet and exercise alone. Investigators evaluated tesamorelin because GHRH analogs can stimulate growth hormone secretion and influence fat distribution without direct liposuction or invasive procedures.
A Phase 3 program led to regulatory approval in the United States in 2010 for reduction of excess visceral abdominal fat in adults with HIV and lipodystrophy. Subsequent studies examined effects on liver fat, muscle area, and metabolic markers, with mixed findings for some endpoints. Long-term cardiovascular outcomes and effects on mortality remain uncertain because most trials were relatively short and focused on imaging-based fat measurements. Use in populations without HIV has been studied experimentally but is not part of the approved indication.
Tesamorelin is a synthetic peptide of forty-four amino acids whose sequence reproduces human growth hormone-releasing hormone. Its distinguishing feature sits at the amino terminus, where a trans-3-hexenoyl group replaces the free amine. That acylation slows cleavage by dipeptidyl peptidase IV, an enzyme that otherwise removes the first two residues and inactivates the natural hormone quickly. The modified peptide therefore persists longer in circulation while keeping the same receptor target. It is handled as a lyophilized solid and dissolved shortly before use.
Signaling begins at the GHRH receptor, a class B G protein-coupled receptor displayed on somatotroph cells of the anterior pituitary. Receptor occupancy activates Gs proteins, which raise adenylyl cyclase activity and intracellular cyclic AMP, in turn driving protein kinase A dependent pathways. The downstream output is synthesis and pulsatile secretion of growth hormone into the bloodstream. Hepatic tissue and peripheral sites respond by increasing insulin-like growth factor 1 production. Somatostatin and IGF-1 itself supply negative feedback that caps the size and duration of each secretory burst.
Metabolic interest in this compound centers on fat distribution rather than on hormone levels alone. Imaging trials in adults with excess abdominal fat report reductions in visceral adipose tissue, while subcutaneous depots change comparatively little. Growth hormone and IGF-1 are presumed to carry the effect, but the separate contribution of each is not firmly established. Whether these changes persist after treatment stops, and whether they alter longer-term health outcomes, remain open questions that published work does not answer consistently.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | Approximately 5,136 Da | Based on the 44-amino-acid peptide backbone and N-terminal modification. |
| Appearance | White to off-white lyophilized powder | Usually supplied in single-use vials for reconstitution. |
| Solubility | Freely soluble in water; slightly soluble in some organic solvents | Peptide nature supports aqueous reconstitution. |
| Typical storage | 2–8 °C, protected from light | Refrigeration reduces degradation; avoid freezing unless specified. |
| Common analytical method | Reverse-phase high-performance liquid chromatography | Used for identity, purity, and quantification. |
| Synonyms | Tesamorelin, TH9507, GHRH(1-44) analog | Generic descriptors; avoid proprietary names. |
Tesamorelin is a synthetic peptide analog of growth hormone-releasing hormone (GHRH). Its sequence corresponds to the 44-amino-acid form of human GHRH with a trans-3-hexenoyl group attached to the N-terminal tyrosine. This modification slows enzymatic cleavage and extends the peptide's activity relative to the native hormone. The compound is produced by solid-phase peptide synthesis and supplied as a lyophilized powder. Researchers classify it as a GHRH receptor agonist. Its structure places it in the same family as other growth hormone secretagogues that act on the pituitary.
Binding of tesamorelin to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and the release of growth hormone into circulation. Because the peptide acts upstream of the growth hormone axis, its effects are partly mediated by hepatic insulin-like growth factor 1 (IGF-1) production. The pulsatile character of endogenous growth hormone secretion is preserved rather than replaced. Whether amplified signaling produces effects beyond those of native GHRH remains an area of ongoing investigation.
A documented effect of tesamorelin is a reduction in visceral adipose tissue in some study populations. Researchers have reported decreases in trunk fat measured by computed tomography alongside changes in lipid markers. The mechanism is thought to involve growth hormone-mediated lipolysis, though the precise contribution of direct versus indirect pathways is not fully resolved. Studies have generally examined defined groups over finite periods, so long-term outcomes are less well characterized. Findings have not been uniform across all trials.
Tesamorelin binds to growth hormone-releasing hormone receptors on the surface of pituitary somatotroph cells. This binding activates adenylate cyclase, raising intracellular cyclic AMP levels and triggering the release of growth hormone into circulation. The elevated growth hormone then stimulates hepatic production of insulin-like growth factor 1. Because the effect is mediated through the endogenous axis, secretion remains subject to feedback regulation. This distinguishes it from direct growth hormone administration, which bypasses pituitary control entirely.
Clinical investigation has focused on HIV-associated lipodystrophy, a condition in which antiretroviral therapy contributes to abnormal fat distribution. Excess visceral adipose tissue accumulates in the abdomen while peripheral fat may be lost. Tesamorelin was evaluated for reducing this visceral fat depot, with trials measuring changes in abdominal fat by imaging rather than by body weight alone. The rationale rests on the known lipolytic effects of growth hormone. Effects on visceral fat are documented, while long-term outcomes regarding cardiovascular risk remain less clearly established.
== M == MAC – macrophage – macrophage-tropic virus – magnetic resonance imaging (MRI) – MAI – maintenance therapy – major histocompatibility complex (MHC) – malabsorption syndrome – malaise – malignant – mast cell – MedlinePlus – mega-HAART – memory T cells – meninges – meningitis – messenger RNA – metabolism – metastasis – MHC – microbes – microbicide – Microsporidiosis – mitochondria – mitochondrial toxicity – molecule – molluscum contagiosum – monocyte – mononeuritis multiplex (MM) – monovalent vaccine – morbidity – MRI – mucocutaneous – mucosa – mucosal immunity – mucous membrane – Multicenter AIDS Cohort Study – multi-drug rescue therapy – multiple drug-resistant tuberculosis (MDR-TB) – mutation – myalgia – mycobacterium – mycobacterium avium complex (MAC) – mycosis – myelin – myelopathy – myelosuppression – myelotoxic – myocardial – myopathy
== Future development == Postmenopausal women may also suffer from HSDD due to a decline in androgen production from menopause. A research proposed two combinations of drugs, each designed against the different causes of HSDD. One combination is to utilise sublingual testosterone with a 5-HT1A receptor agonist to raise motivation for sex, by lifting the inhibition mechanisms in the brain's prefrontal regions. Testosterone is also proposed to be coupled with the PDE5 inhibitor, targeting an insensitive system for the production of sexual desire. As both clinical trials showed desirable results, this indicates the prosperity of further developing a single drug targeting HSDD for all women of different status, even though the FDA has not approved the two combinations.
Vitamin D: insufficiency is common in diabetics. Observational studies show that serum vitamin D is inversely associated with biomarkers of diabetes; impaired insulin secretion, insulin resistance, and glucose intolerance. It has been suggested that vitamin D may induce beneficial effects on diabetic complications by modulating differentiation and growth of pancreatic β-cells and protecting these cells from apoptosis, thus improving β-cells functions and survival. In particular, vitamin D supplementation has been shown to have positive effects on people with type 1 diabetes. Vitamin D has also been suggested to act on immune system and modulate inflammatory responses by influencing proliferation and differentiation of different immune cells., Moreover, deficiency of vitamin D may contribute to diabetic complications by inducing hyperparathyroidism, since elevated parathyroid hormone levels are associated with reduced β-cells function, impaired insulin sensitivity, and glucose intolerance. Finally, vitamin D may reduce the risk of vascular complications by modulating lipid profile. Antioxidants may have beneficial effects on diabetic complications by reducing blood pressure, attenuating oxidative stress and inflammatory biomarkers, improving lipid metabolism, insulin-mediated glucose disposal, and by enhancing endothelial function. Vitamin C has been proposed to induce beneficial effects by two other mechanisms.
Sources: en.wikipedia.org
A study assessed urinary levels of pregnanediol glucuronide, the major metabolite of progesterone in urine, and found that although circulating progesterone levels and urinary levels of pregnanediol glucuronide increased after treatment with transdermal progesterone, the levels of both nonetheless remained in the range of the follicular phase and hence were very low. A case report found that the 5α-reductase inhibitor finasteride did not increase the circulating progesterone levels or urinary pregnanediol glucuronide levels produced by transdermal progesterone. Likewise, a study found that the 5α-reductase inhibitor dutasteride resulted in only slightly higher progesterone levels with transdermal progesterone. Finally, 5α-reductase is also a major enzyme involved in the metabolism of testosterone, yet transdermal testosterone is approved for androgen replacement therapy and is very effective in raising testosterone levels. In terms of elimination, a study that investigated the pharmacokinetics of transdermal progesterone using either a hydrophilic-, lipophilic-, or emulsion-type base found that in all three cases the elimination half-life was in the range of 30 to 40 hours.
=== 6 May === The RSF launched another series of drone strikes on Port Sudan. Six people were killed by RSF shelling on the Abu Shouk camp. The Sudanese government severed diplomatic relations with the UAE due to its alleged support for the RSF.
Other studies confirm a dependence of ESR on age and gender, as seen in the following: ESR reference ranges from a large 1996 study of 3,910 healthy adults (NB. these use 95% confidence intervals rather than the 98% intervals used in the study used to derive the formula above, and because of the skewness of the data, these values appear to be less than expected from the above formula):
Sources: en.wikipedia.org
17 February – A global review of harms from personal car automobility finds cars have killed 60–80 million people since their invention, with automobility causing roughly every 34th death, and summarises interventions that are ready for implementation to reduce the, largely crash-linked or pollution-mediated, deaths from automobility-centrism and dependency. 19 February Astronomers announce the most luminous object ever discovered, quasar QSO J0529-4351, located 12 billion light-years away in the constellation Pictor. Researchers with the University of Tennessee and University of Missouri publish an academic study about how survivors from the 2011 Joplin tornado recover from "Tornado Brain", a new term for the PTSD of tornado survivors. 20 February – The northern green anaconda (Eunectes akayima), a new species of the giant snake, is described for the first time. 21 February Researchers use artificial intelligence to forecast plasma instabilities in fusion reactors up to 300 milliseconds in advance. The first neuroimaging study that shows flow state-related brain activity during a creative production task, jazz improvisation, is published. Its results support a theory that creative flow represents optimized specialized processing enabled by extensive experience, relaxing conscious control.
Ornithine is not an amino acid directly coded for by DNA; that is, it is not a proteinogenic amino acid. However, in mammalian non-hepatic tissues, the primary role of the urea cycle is often the biosynthesis of arginine. As an intermediate in metabolic pathways, ornithine is thus quite important.
== Symmetric hydrogen bond == A symmetric hydrogen bond is a special type of hydrogen bond in which the proton is spaced exactly halfway between two identical atoms. The strength of the bond to each of those atoms is equal. It is an example of a three-center four-electron bond. This type of bond is much stronger than a "normal" hydrogen bond. The effective bond order is 0.5, so its strength is comparable to a covalent bond. It is seen in ice at high pressure, and also in the solid phase of many anhydrous acids such as hydrofluoric acid and formic acid at high pressure. It is also seen in the bifluoride ion [F···H···F]−. Due to severe steric constraint, the protonated form of Proton Sponge (1,8-bis(dimethylamino)naphthalene) and its derivatives also have symmetric hydrogen bonds ([N···H···N]+), although in the case of protonated Proton Sponge, the assembly is bent.
Paper chromatography is an analytical method used to separate colored chemicals or substances. It can also be used for colorless chemicals that can be located by a stain or other visualisation method after separation. It is now primarily used as a teaching tool, having been replaced in the laboratory by other chromatography methods such as thin-layer chromatography (TLC). This analytic method has three components, a mobile phase, stationary phase and a support medium (the paper). The mobile phase is generally a non-polar organic solvent in which the sample is dissolved. The stationary phase consists of (polar) water molecules that were incorporated into the paper when it was manufactured. The mobile phase travels up the stationary phase by capillary action, carrying the sample with it. The difference between TLC and paper chromatography is that the stationary phase in TLC is a layer of adsorbent (usually silica gel, or aluminium oxide), and the stationary phase in paper chromatography is less absorbent paper. A paper chromatography variant, two-dimensional chromatography, involves using two solvents and rotating the paper 90° in between. This is useful for separating complex mixtures of compounds having similar polarity, for example, amino acids.
Sources: en.wikipedia.org
It is a synthetic peptide analog of human growth hormone-releasing hormone. It is used clinically to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy. It works by stimulating pituitary growth hormone release.
Pivotal trials enrolled adults with HIV and excess visceral abdominal fat, often in the context of antiretroviral therapy. Participants were assessed mainly by computed tomography for visceral adipose tissue. The approved indication remains specific to that population.
Long-term effects on cardiovascular events, mortality, and sustained fat distribution are not well established. Most trials measured changes over months rather than years. Open questions also include whether benefits persist after treatment stops.
The amino acid sequence matches human growth hormone-releasing hormone, but the amino terminus carries a trans-3-hexenoyl group instead of a free amine. That single structural change chiefly affects enzymatic stability rather than receptor selectivity.