If you have been reading about visceral fat and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-01-26. Numbers and descriptions here follow the published literature rather than marketing material.
研究背景集中在特定人群的体成分改变，尤其是与脂肪分布异常相关的内脏脂肪堆积。不同地区对它的监管状态与获批适应症并不一致，部分市场仅限特定诊断人群使用。在一般人群中的长期效应、与其他激素的相互作用以及停药后的维持情况仍属开放问题，现有数据不足以给出普遍结论。
tesamorelin 是一种人工合成的四十四肽，序列与内源性生长激素释放激素（GHRH）的 1-44 片段一致，区别在于 N 端加接了一个反式-3-己烯酰基。该修饰抑制二肽基肽酶 IV 的快速切割，从而延长分子在循环中的存留时间。作为肽类分子，它难以经胃肠道吸收，文献中讨论的均是注射途径。分类上通常把它归为 GHRH 类似物，以区别于生长激素本身。
Pharmacodynamic studies show that tesamorelin reduces visceral adipose tissue more than subcutaneous adipose tissue in the studied population. This selectivity may relate to differences in blood flow and hormone sensitivity between fat depots. Effects on glucose metabolism and insulin sensitivity have been investigated, with some trials reporting modest changes and others showing stability. The precise relationship between growth hormone exposure, IGF-1 levels, and visceral fat loss remains an active area of analysis.
Tesamorelin binds to growth hormone-releasing hormone receptors on somatotroph cells in the anterior pituitary. Receptor activation increases intracellular cyclic AMP and promotes synthesis and secretion of growth hormone. Because the peptide mimics endogenous GHRH, it amplifies the normal pulsatile release of growth hormone rather than providing exogenous growth hormone directly. This upstream action distinguishes tesamorelin from recombinant growth hormone preparations and from growth hormone secretagogues that act at different receptors.
Stimulated growth hormone release leads to hepatic production of insulin-like growth factor 1, a key mediator of many growth hormone effects. In clinical studies, tesamorelin increased IGF-1 levels in a dose-dependent manner, although the response varies among individuals. The drug's effect on visceral fat is thought to involve growth hormone-mediated lipolysis and altered adipocyte metabolism. Muscle mass and lean body mass have also been assessed as secondary outcomes, but changes are generally smaller and less consistent than fat reductions.
| 性质 | 取值 | 备注 |
|---|---|---|
| 分子类型 | 合成四十四肽 | GHRH 类似物 |
| N 端修饰 | 反式-3-己烯酰基 | 延缓酶切 |
| 分子量 | 约 5135 Da | 依序列与修饰 |
| 受体靶点 | 垂体 GHRH 受体 | 经 cAMP 通路 |
| 常见同义名 | GHRH(1-44) 类似物 | 文献通用称法 |
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.
Tesamorelin is a synthetic peptide analog of growth hormone-releasing hormone, composed of 44 amino acids. It was designed to retain the biological activity of the native hormone while resisting rapid enzymatic degradation. The compound is classified as a growth hormone secretagogue and belongs to the broader family of hypothalamic releasing factors. In research and clinical settings, it is studied for its ability to stimulate pituitary growth hormone release. Its structure includes a modification at the N-terminus that contributes to an extended half-life relative to native growth hormone-releasing hormone.
Tesamorelin binds the growth hormone–releasing hormone receptor on pituitary somatotroph cells. The receptor signals through the Gs protein, raising intracellular cAMP and activating protein kinase A. That cascade triggers release of stored growth hormone in pulses rather than a steady stream. Because the drug acts at the receptor that normally controls this process, its effect depends on the body's own signaling architecture rather than on a synthetic pathway. The resulting hormone profile reflects the timing of each pulse, not only its size.
Measured responses usually involve growth hormone and insulin-like growth factor 1, known as IGF-1. Growth hormone rises in bursts and is difficult to sample reliably, while IGF-1 shifts more slowly and can be assessed from a single blood draw. Studies therefore treat IGF-1 as the more practical pharmacodynamic marker. Both are indirect, showing that the receptor was engaged rather than that the peptide reached a particular concentration. Direct exposure measurement requires an assay aimed at the molecule itself.
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.
The Bayview Campus in Baltimore, Maryland houses the research programs of the National Institute on Aging, National Institute on Drug Abuse, and National Human Genome Research Institute with nearly 1,000 scientists and support staff. The Frederick National Laboratory in Frederick, MD and the nearby Riverside Research Park, houses many components of the National Cancer Institute, including the Center for Cancer Research, Office of Scientific Operations, Management Operations Support Branch, the division of Cancer Epidemiology and Genetics and the division of Cancer Treatment and Diagnosis. The National Institute of Environmental Health Sciences is located in the Research Triangle region of North Carolina. Other ICs have satellite locations in addition to operations at the main campus. The National Institute of Allergy and Infectious Diseases maintains its Rocky Mountain Labs in Hamilton, Montana, with an emphasis on BSL3 and BSL4 laboratory work. NIDDK operates the Phoenix Epidemiology and Clinical Research Branch in Phoenix, Arizona.
== Regulation == The flux of the entire pathway is regulated by the rate-determining steps. These are the slowest steps in a network of reactions. The rate-limiting step occurs near the beginning of the pathway and is regulated by feedback inhibition, which ultimately controls the overall rate of the pathway. The metabolic pathway in the cell is regulated by covalent or non-covalent modifications. A covalent modification involves an addition or removal of a chemical bond, whereas a non-covalent modification (also known as allosteric regulation) is the binding of the regulator to the enzyme via hydrogen bonds, electrostatic interactions, and Van der Waals forces. The rate of turnover in a metabolic pathway, also known as the metabolic flux, is regulated based on the stoichiometric reaction model, the utilization rate of metabolites, and the translocation pace of molecules across the lipid bilayer. The regulation methods are based on experiments involving 13C-labeling, which is then analyzed by nuclear magnetic resonance (NMR) or gas chromatography–mass spectrometry (GC–MS)–derived mass compositions. The aforementioned techniques synthesize a statistical interpretation of mass distribution in proteinogenic amino acids to the catalytic activities of enzymes in a cell.
==== Adverse effect ==== The common early side effects of SSRIs include nausea and loose stool, which can be solved by discontinuing the treatment. Headache, dizziness, insomnia are the common early side effects as well. Sexual dysfunction, anorgasmia, erectile dysfunction, and reduced libido are common adverse side effects of SSRIs. Sometimes they may persist after the cessation of treatment. Withdrawal symptoms like dizziness, headache and flu-like symptoms (fatigue/myalgia/loose stool) may occur if SSRI is stopped suddenly. The brain is incapable of upregulating the receptors to sufficient levels especially after discontinuation of the drugs with short half-life like paroxetine. Both fluoxetine and its active metabolite have a long half-life therefore it causes the least withdrawal symptoms.
The biosynthetic machinery of an NRPS system is composed of multimodular enzymatic assembly lines that contain one module for each amino acid monomer incorporated. Within each module are catalytic domains that carry out the elongation of the growing peptidyl chain. The growing peptide is covalently tethered to a thiolation domain; here it is termed the peptidyl carrier protein, as it carries the growing peptide from one catalytic domain to the next. Again, the apo-T domain must be primed to the holo-T domain by a PPTase, attaching a flexible phosphopantetheine arm to a conserved serine residue. An adenylation domain selects the amino acid monomer to be incorporated and activates the carboxylate with ATP to make the aminoacyl-AMP. Next, the A domain installs an aminoacyl group on the thiolate of the adjacent T domain. The condensation (C) domain catalyzes the peptide bond forming reaction, which elicits chain elongation. It joins an upstream peptidyl-S-T to the downstream aminoacyl-S-T (Figure 7). Chain elongation by one aminoacyl residue and chain translocation to the next T domain occurs in concert. The order of these domains is C-A-T. In some instances, an epimerization domain is necessary in those modules where L-amino acid monomers are to be incorporated and epimerized to D-amino acids. The domain organization in such modules is C-A-T-E. The first module has a three-domain C-A-T organization; these often occur in assembly lines that make N-acylated peptides. The first C domain catalyzes N-acylation of the initiating amino acid (tryptophan) while it is installed on T.
Biological value (BV) is a measure of the proportion of absorbed protein from a food which becomes incorporated into the proteins of the organism's body. It captures how readily the digested protein can be used in protein synthesis in the cells of the organism. Proteins are the major source of nitrogen in food. BV assumes protein is the only source of nitrogen and measures the amount of nitrogen ingested in relation to the amount which is subsequently excreted. The remainder must have been incorporated into the proteins of the organisms body. A ratio of nitrogen incorporated into the body over nitrogen absorbed gives a measure of protein "usability" – the BV. Unlike some measures of protein usability, biological value does not take into account how readily the protein can be digested and absorbed (largely by the small intestine). This is reflected in the experimental methods used to determine BV. BV uses two similar scales:
Sources: en.wikipedia.org
the equation reduces to the incompressible-flow form. The constant on the right-hand side is often called the Bernoulli constant and denoted b. For steady inviscid adiabatic flow with no additional sources or sinks of energy, b is constant along any given streamline. More generally, when b may vary along streamlines, it still proves a useful parameter, related to the "head" of the fluid (see below). When the change in Ψ can be ignored, a very useful form of this equation is:
Geckos, skinks, and some other lizards that are captured by the tail will shed part of the tail structure through a process called autotomy and thus be able to flee. The detached tail will continue to thrash, creating a deceptive sense of continued struggle and distracting the predator's attention from the fleeing prey animal. The detached tails of leopard geckos can wiggle for up to 20 minutes. The tail grows back in most species, but some, like crested geckos, lose their tails for the rest of their lives. In many species the tails are of a separate and dramatically more intense color than the rest of the body so as to encourage potential predators to strike for the tail first. In the shingleback skink and some species of geckos, the tail is short and broad and resembles the head, so that the predators may attack it rather than the more vulnerable front part. Reptiles that are capable of shedding their tails can partially regenerate them over a period of weeks. The new section will however contain cartilage rather than bone, and will never grow to the same length as the original tail. It is often also distinctly discolored compared to the rest of the body and may lack some of the external sculpting features seen in the original tail.
Banting, November 14, 1891–February 22, 1941". Journal of the American Dietetic Association. 29 (11): 1093. PMID 13108539. Les caprices du Nobel by William Rostène, ed. L'Harmattan (Paris), 2013 (in French) ISBN 978-2-343-01844-7
=== Original BCA assay === As described by Smith, the original BCA assay is a two-component protocol. The two reagents are "stable indefinitely at room temperature". Modern (likely exact or highly similar) formulations are available from at least two commercial vendors. The BCA Working solution is generated by mixing Reagent A and Reagent B in a 50:1 ratio, and can be prepared either weekly (it is moderately stable), or as needed. Reagent A
Sources: en.wikipedia.org
== SW == sw – (s) Swahili language (ISO 639-1 code) SW (s) South-West ordinal direction Sweden (FIPS 10-4 country code) (a) Shortwave Star Wars swa – (s) Swahili language (ISO 639-2 code) SWA (i/a) Secure Web Access South-West Asia SWAC – (p) Southwestern Athletic Conference SWAG Scientific wild-ass guess, slang for a rough estimate based on expert experience Sourceware Archive Group, a free collection of classified source code and sample programs written in Pascal Sport Writers Association of Ghana, Sports Writers Association based in Ghana Special Warfare Group, a former name used by the Naval Special Operations Command "Supporters Without A Game", sport slang spun off from WAGs ("wives and girlfriends") SWALK – (a) Sealed With A Loving Kiss SWAN – (a) System for Wearable Audio Navigation SWAP – (a) Surface Waters Acidification Programme SWAPO – (a) South-West Africa People's Organisation SWAT – (a) Special Weapons And Tactics swe – (s) Swedish language (ISO 639-2 code) SWE – (s) Sweden (ISO 3166 trigram) SWF (p) Shockwave Flash file ("swiff") Single White Female SWG (i) Surface Warfare Group Symbology Working Group SWHR – (i) Society for Women's Health Research SWIG – (a) Simplified Wrapper and Interface Generator SWIR – (a/i) Short Wave InfraRed ("ss-why-are" or "swhirr") SWLABR – (i) "She Was Like A Bearded Rainbow", a song by the band Cream SWORD – (p) Subjective WORkload Dominance SWORDS – (a) Special Weapons Observation Reconnaissance Detection System SWOT – (a) Strengths, Weaknesses, Opportunities, Threats (mnemonic) SWP (i) Special Working Party ("swipp") Systematic Westing Plan (a plan of periodic westing of shares or mutual funds worth a fixed amount of money) Skill with prize (UK pub quiz machines — quality titles include: Pub Quiz, Quiz City, Frog in a Liquidizer, Who Wants To Win a Tenner?) SWT – (i) Sea Water Tank SWV – (i) Sisters With Voices (American female R&B vocal group) SWZ – (s) Swaziland (ISO 3166 trigram)
=== Presymbiosis === To form an ectomycorrhizal connection, the fungal hyphae must first grow towards the plant's roots. Then they must envelope and penetrate the root cap cells and infect them, allowing the symbiotic Hartig net and associated structures to form. Both partners (plant and fungus) must follow a precise sequence of gene expression for this to be successful. There is evidence that communication between the partners in the early stage of ectomycorrhiza occurs in some cases via volatile organic compounds produced only during the interaction phase, and that genes involved in secretory, apical growth, and infection processes show changes in expression early in the pre-contact phase. Thus, a complex set of molecular changes appears to take place even before the fungus and host plant make contact. The plant hosts release metabolites into the rhizosphere that can trigger basidiospore germination, growth of hyphae towards the root, and the early steps of EcM formation. These include flavonoids, diterpenes, cytokinins, hormones and other nutrients. Some host-released metabolites have been shown to stimulate fungal growth in Pisolithus, modify the branching angle of hyphae, and cause other changes in the fungus. Some fungal genes appear to be expressed before plant contact, suggesting that signals in the soil may induce important fungal genes at a distance from the plant.
where the final substitution, N0 = eC, is obtained by evaluating the equation at t = 0, as N0 is defined as being the quantity at t = 0. This is the form of the equation that is most commonly used to describe exponential decay. Any one of decay constant, mean lifetime, or half-life is sufficient to characterise the decay. The notation λ for the decay constant is a remnant of the usual notation for an eigenvalue. In this case, λ is the eigenvalue of the negative of the differential operator with N(t) as the corresponding eigenfunction.
Sources: en.wikipedia.org
tesamorelin 属 GHRH 类似物，作用于垂体受体以促进内源生长激素释放；生长激素本身是直接补充的外源激素。两者在给药逻辑、作用位点和反馈调控路径上并不相同。
作为多肽，它难以通过胃肠道吸收，通常需要注射给药。口服会因消化酶降解而失去活性，因此文献中讨论的都是注射途径。
公开研究多集中在内脏脂肪、体成分分布以及与生长激素轴相关的代谢指标。长期安全性和在普通人群中的适用性尚缺乏一致结论。
It targets the growth hormone-releasing hormone receptor on pituitary somatotroph cells. Binding stimulates cyclic AMP signaling and growth hormone secretion. This is the same receptor used by endogenous GHRH.