Insulin-like growth factor 1 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-04-22. Numbers and descriptions here follow the published literature rather than marketing material.
监管记录显示,特沙莫瑞林于 2010 年在美国首次获得批准,用于人类免疫缺陷病毒感染相关的脂肪营养不良患者。批准依据来自降低内脏脂肪的临床试验,而非体重或瘦体重的普遍改善。后续出现了不同制剂版本,但其核心适应症保持一致。关于长期心血管结局和死亡率影响,现有证据仍不充分。
在临床研究之外,特沙莫瑞林常被讨论为生长激素分泌促进剂,但这一说法需要限定。它并不等同于生长激素本身,也不属于普通减重药物。部分研究关注其减少腹部脂肪和改善脂质谱的潜力,另一些研究则关注胰岛素抵抗和 IGF-1 升高等信号。这些效应的临床意义仍在评估中,尚未形成统一结论。
特沙莫瑞林是一种合成肽,其序列与人生长激素释放激素的 44 个氨基酸形式相关。它在 N 端带有反式-3-己烯酰基修饰,这一改动可减缓二肽基肽酶 IV 的降解。该化合物属于生长激素释放激素受体激动剂,可刺激垂体释放生长激素。研究文献通常将其归入合成肽类药物,而非小分子化合物。
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.
| Property | Value | Notes |
|---|---|---|
| 分子类型 | 合成肽 | 含 44 个氨基酸残基的 GHRH 类似物 |
| N 端修饰 | 反式-3-己烯酰基 | 用于抵抗二肽基肽酶 IV 降解 |
| 首次批准 | 2010 年,美国 | 用于 HIV 相关脂肪营养不良 |
| 作用靶点 | 生长激素释放激素受体 | 位于垂体前叶 |
| 主要研究终点 | 内脏脂肪变化 | 非总体重或瘦体重 |
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.
Whether the drug improves hard clinical outcomes is not settled. No completed trial has shown a reduction in heart attacks or strokes among treated patients, although a dedicated cardiovascular outcomes study has been discussed in the literature. Investigators have also examined hepatic fat in people with HIV and fatty liver disease, cognitive measures in small cohorts, and changes in bone density. Regulatory labeling emphasizes monitoring of insulin-like growth factor 1 because supraphysiologic levels raise questions about tissue growth, and the clinical significance of that signal remains an open question rather than a demonstrated harm.
Binding of tesamorelin to the growth hormone-releasing hormone receptor on anterior pituitary somatotrophs activates a Gs protein pathway, raises cyclic AMP, and triggers release of stored growth hormone into the bloodstream. Because the analogue resists dipeptidyl peptidase-4, its plasma residence time exceeds that of native GHRH, producing a larger and more sustained secretory signal. The released growth hormone then acts on the liver and peripheral tissues to raise insulin-like growth factor 1, which feeds back on the hypothalamus and pituitary. This axis explains both the intended effects on fat distribution and the biological markers used to track them.
Tesamorelin occupies a narrow position among agents that act on the growth hormone axis. Unlike growth hormone itself, which is given as replacement, it stimulates the pituitary to release the hormone in pulses, so the downstream increase in insulin-like growth factor 1 depends on intact somatotroph function. Other peptides in the same family include shorter GHRH fragments and synthetic secretagogues with different stability profiles. Several points remain unresolved, including whether the reduction in visceral fat translates into fewer cardiovascular events, what happens to metabolic markers after long-term use, and how the drug compares with lifestyle or surgical approaches.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone family and contains the same forty-four amino acid sequence as endogenous GHRH, extended at the amino terminus by a trans-3-hexenoyl group. That small fatty acid modification protects the peptide from rapid cleavage by dipeptidyl peptidase-4, the enzyme that shortens the half-life of native GHRH to only a few minutes. Chemically the compound is produced by solid-phase peptide synthesis, purified by chromatography, and supplied as a sterile lyophilized powder for reconstitution.
Questions remain about how much of the observed fat reduction reflects direct GHRH-receptor signaling versus the downstream growth hormone and IGF-1 surge. It is also unclear whether the compound produces meaningful benefit in populations without lipodystrophy, since trials in cognitive impairment did not reach their stated goals. Long-term effects on glucose metabolism and on cardiovascular outcomes are not fully characterized. Published work generally describes effects on surrogate markers rather than on hard clinical endpoints, and independent replication of some findings is limited.
Tesamorelin acts on the growth hormone-releasing hormone receptor, a G-protein-coupled receptor found on somatotroph cells in the anterior pituitary. Binding triggers a rise in intracellular cyclic AMP, which in turn opens ion channels and raises calcium concentrations, leading to release of stored growth hormone into the bloodstream. Because the peptide works through the same receptor as the body's own GHRH, the resulting secretion follows a pulsatile pattern rather than a continuous elevation. The N-terminal modification slows enzymatic breakdown, so the signal persists longer than it would with the unmodified hormone.
Growth hormone released from the pituitary stimulates the liver and other tissues to produce insulin-like growth factor 1, a stable circulating protein that serves as a practical marker of activity. Clinical studies therefore track IGF-1 concentrations alongside the hormone itself, and they commonly measure body composition with imaging rather than relying on body weight alone. Visceral adipose tissue, the fat surrounding abdominal organs, is quantified by computed tomography in the studies that supported approval. Adverse effects reported in trials include injection-site reactions, joint pain, and increases in blood glucose, which is why monitoring accompanies use.
== History == Hans Christian Hagedorn (1888–1971) and August Krogh (1874–1949) obtained the rights for insulin from Frederick Banting and Charles Best in Toronto, Canada. In 1923 they formed Nordisk Insulin laboratorium, and in 1926 with August Kongsted he obtained a Danish royal charter as a non-profit foundation. In 1936, Hagedorn and B. Norman Jensen discovered that the effects of injected insulin could be prolonged by the addition of protamine obtained from the "milt" or semen of river trout. The insulin would be added to the protamine, but the solution would have to be brought to pH 7 for injection. University of Toronto, Canada later licensed protamine zinc insulin (PZI), to several manufacturers. This mixture only needs to be shaken before injection. The effects of PZI lasted for 24–36 h.
== Narcoterrorism == An unwanted by-product of Bolivia's cocaine industry was the importation of Colombian-style drug violence. In the late 1980s, Colombia's Medellín Cartel reportedly wielded considerable power in Bolivia, setting prices for coca paste and cocaine and terrorizing the drug underworld with hired assassins. Furthermore, drug barons, organized into families, had established their own fiefdoms in Cochabamba, Beni, and Santa Cruz departments, using bribes and assassinations to destroy local authority. In September 1986, three members of a Bolivian scientific team were slain in the Huanchaca National Park in Santa Cruz Department shortly after their aircraft landed beside a clandestine coca-paste factory. The murders led to the discovery of the country's largest cocaine-processing installation, as well as evidence of an extensive international drug-trafficking organization consisting mostly of Colombians and Brazilians. President Paz Estenssoro fired the Bolivian police commander and deputy commander as a result of their alleged involvement. In a related action, suspected traffickers in Santa Cruz murdered an opposition deputy who was a member of the congressional commission that investigated the Huanchaca case. In the late 1980s, there were several incidents of narcoterrorism against the United States presence, the judiciary, and antidrug agents. For example, the so-called Alejo Calatayu terrorist command claimed responsibility for a May 1987 bomb attack against the Cochabamba home of a DEA agent.
The educational background of the researchers and their socialization process. The intellectual process involved in their work, including the type of investigation and equipment they use. The laboratory's history. Other forms of organization include social organization.
Side effects of fentanyl analogues are similar to those of fentanyl itself, which include itching, nausea and potentially serious respiratory depression, which can be life-threatening. Illicitly used fentanyl analogues have killed hundreds of people throughout Europe and the former Soviet republics since the most recent resurgence in use began in Estonia in the early 2000s, and novel derivatives continue to appear.
=== Based on absorption === Drugs that change intestinal motility may impact the level of other drugs taken. For example, prokinetic agents increase the intestinal motility, which may cause drugs to go through the digestive system too fast, reducing absorption. The pharmacological modification of pH can affect other compounds. Drugs can be present in ionized or non-ionized forms depending on pKa, and neutral compounds are usually better absorbed by membranes. Medication like antacids can increase pH and inhibit the absorption of other drugs such as zalcitabine, tipranavir and amprenavir. The opposite is more common, with, for example, the antacid cimetidine stimulating the absorption of didanosine. Some resources describe that a gap of two to four hours between taking the two drugs is needed to avoid the interaction. Factors such as food with high-fat content may also alter the solubility of drugs and impact its absorption. This is the case for oral anticoagulants and avocado. The formation of non-absorbable complexes may occur also via chelation, when cations can make certain drugs harder to absorb, for example between tetracycline or the fluoroquinolones and dairy products, due to the presence of calcium ions. . Other drugs bind to proteins. Some drugs such as sucralfate bind to proteins, especially if they have a high bioavailability. For this reason its administration is contraindicated in enteral feeding. Some drugs also alter absorption by acting on the P-glycoprotein of the enterocytes.
Sources: en.wikipedia.org
Globin proteins and thus their genes have an ancient evolutionary origin. Even plants have a form of globin called leghemoglobin which shares about 15% of its sequence with hemoglobin. While this level of similarity may be caused by chance, the 3-dimensional structure of both proteins is so similar that it is commonly assumed that they have a common origin. This is confirmed by the conservation of intron positions in both types of genes. Variations in hemoglobin sequences, as with other proteins, may be adaptive. For example, hemoglobin has been found to adapt in different ways to the thin air at high altitudes, where lower partial pressure of oxygen diminishes its binding to hemoglobin compared to the higher pressures at sea level. Recent studies of deer mice found mutations in four genes that can account for differences between high- and low-elevation populations. It was found that the genes of the two breeds are "virtually identical—except for those that govern the oxygen-carrying capacity of their hemoglobin. . . . The genetic difference enables highland mice to make more efficient use of their oxygen."
=== Burger Chef trademark dispute === In January 2007, Hardee's had a challenge filed against it with the U.S. Patents and Trademarks Office by River West Brands, LLC of Chicago for the use of the Burger Chef trademark and name. Shortly thereafter, Hardee's reissued the Burger Chef Big Shef sandwich in Terre Haute, Indiana, as a trial offering and later in additional Indiana markets and Dayton, Ohio, for a limited time. The reissue of the Big Shef has also used the Burger Chef name and logo in advertisements in the markets in which it is offered, and has claimed to provide Burger Chef fans with their Big Shef "fix". On April 16, 2009, River West Brands dropped their petition for cancellation and both parties agreed to pay their own attorney's fees.
Endothelin 1 (ET-1), also known as preproendothelin-1 (PPET1), is the most potent vasoconstrictor produced by the human body. It is a peptide produced by vascular endothelial cells, as well as by cells in the heart (affecting contractility) and kidney (affecting sodium handling). The protein encoded by this gene – EDN1 – is proteolytically processed to release endothelin 1. Endothelin 1 is one of three isoforms of human endothelin.
In adults, wasting (or cachexia) caused by AIDS. Turner syndrome epitomizes the response of non-deficient shortness. At doses 20% higher than those used in GH deficiency, growth accelerates. With several years of treatment the median gain in adult height is about 5-8 cm on this dose. The gains appear to be dose-dependent. It has been used successfully in toddlers with Turner syndrome, as well as in older girls. Short-stature homeobox gene deficiency Chronic kidney failure results in many problems, including growth failure. GH treatment for several years both before and after transplantation may prevent further deceleration of growth and may narrow the height deficit, though even with treatment net adult height loss may be about 10 cm Prader–Willi syndrome, a generally non-hereditary genetic condition, is a case where GH is prescribed for benefits in addition to height. GH is one of the treatment options an experienced endocrinologist may use when treating a child with PWS. GH can help children with PWS in height, weight, body mass, strength, and agility. . Reports have indicated increase of growth rate (especially in the first year of treatment) and a variety of other positive effects, including improved body composition (higher muscle mass, lower fat mass); improved weight management; increased energy and physical activity; improved strength, agility, and endurance; and improved respiratory function. The Prader–Willi Syndrome Association (US) recommends that a sleep study be conducted before initiating GH treatment in a child with PWS.
Sources: en.wikipedia.org
特沙莫瑞林是国际非专利名称,指一种经过 N 端修饰的生长激素释放激素类似物。它被归类为合成肽,序列与 GHRH(1-44) 密切相关。该名称不指代任何特定品牌或剂型。
监管批准集中于 HIV 感染相关的脂肪营养不良,目的是减少内脏脂肪。它未被批准用于普通肥胖或一般体重管理。不同国家的批准状态和标签范围可能不同。
长期心血管获益、死亡率影响以及停药后的持续性仍缺乏确证。部分研究提示 IGF-1 和血糖参数可能变化,但个体差异较大。这些开放问题需要更长期、更大规模的试验来回答。
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.