This is a working overview of 合成肽, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-08-24. Anything still debated is marked as such rather than presented as settled.
The native hormone is produced in the hypothalamus and acts on the anterior pituitary. Binding of GHRH to its receptor stimulates synthesis and release of growth hormone into circulation. Because the analogue retains the receptor-binding region of the parent sequence, it engages the same receptor and triggers the same downstream signaling. The result is increased growth hormone secretion from pituitary cells, which in turn influences hepatic production of insulin-like growth factor 1. This axis is the basis for the compound's measured biological effects.
Interest in this peptide developed because native GHRH has a short circulating lifetime. The N-terminal modification slows cleavage by dipeptidyl peptidase IV, an enzyme that removes the first two residues of many peptides and terminates their activity. Slower degradation means a longer window of receptor stimulation per administration. This design logic parallels other modified peptide hormones, where a small chemical change at a vulnerable site yields a more durable molecule without altering the core mechanism of action.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C221H366N72O67S | Reflects a 44-residue peptide with one N-terminal modification |
| Approximate molecular weight | 5136 Da | Sequence length and single acyl group determine the mass |
| Appearance | White to off-white lyophilized powder | Typical form of a purified synthetic peptide |
| Solubility class | Soluble in water and aqueous buffer | Peptide backbone favors aqueous dissolution |
| Common synonyms | GHRH(1-44) analogue; Egrifta | Descriptive name and approved brand name |
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.
Regulatory approval in the United States came in 2010, when the Food and Drug Administration cleared the peptide for the reduction of excess abdominal fat in adults with HIV infection and associated lipodystrophy. The decision rested mainly on two randomized phase 3 trials that enrolled roughly eight hundred patients and ran for twenty-six weeks. Participants receiving active drug showed substantially greater declines in visceral adipose tissue than those receiving placebo, while total body weight changed comparatively little. A reformulated presentation was later approved, and the product has remained a niche therapy rather than a general weight-loss agent.
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 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 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.
Alcohol-induced dose dumping (AIDD) is an unintended rapid release of large amounts of a given drug, when administered through a modified-release dosage while co-ingesting ethanol. This is considered a pharmaceutical disadvantage due to the high risk of causing drug-induced toxicity by increasing the absorption and serum concentration above the therapeutic window of the drug. The best way to prevent this interaction is by avoiding the co-ingestion of both substances or using specific controlled-release formulations that are resistant to AIDD. Particular drugs of concern are antipsychotics and certain antidepressants.
Eighteen local authorities have applied to delay their elections until 2026 amid proposals for major reorganisation. Ed Davey calls for Britain to re-join the European Union Customs Union. MP Joe Morris raises the topic of "Holly's Law" in Prime Minister's Questions. 16 January – Keir Starmer signs a 100-year treaty with Ukraine in Kyiv. Home Secretary Yvette Cooper announces plans for a nationwide review of grooming gangs including five government-backed local inquiries. Kemi Badenoch criticises her predecessors for mishandling Brexit. Downing Street clears Emma Reynolds to be City Minister despite her past work as a lobbyist. MP Mike Amesbury admits to assault at Chester Magistrates' Court. The White House announces that Ian Paisley Jr will attend the second inauguration of Donald Trump. 17 January – The Greater London Authority is to investigate Mayor of London Sadiq Khan for his acceptance of tickets to a Taylor Swift concert. Westminster's Strangers' Bar is to close for a safety and security review after a report that a woman had her drink spiked. The Liberal Democrats urge the UK government to release analysis of the potential impact of the US imposing trade tariffs on the UK economy after US President-elect Donald Trump threatened to impose tariffs of up to 20% on global imports.
=== Preventing further liver damage === Regardless of the underlying cause of cirrhosis, consumption of alcohol and other potentially damaging substances is discouraged. There is no evidence that supports the avoidance or dose reduction of paracetamol in people with compensated cirrhosis; it is thus considered a safe analgesic for said individuals. Vaccination against hepatitis A and hepatitis B is recommended early in the course of illness due to a decline in effectiveness of the vaccines with decompensation. Treating the cause of cirrhosis prevents further damage; for example, giving oral antivirals such as entecavir and tenofovir where cirrhosis is due to hepatitis B prevents progression of cirrhosis. Similarly, control of weight and diabetes prevents deterioration in cirrhosis due to non-alcoholic fatty liver disease. People with cirrhosis or liver damage are often advised to avoid drugs that could further harm the liver. These include several drugs such as anti-depressants, certain antibiotics, and NSAIDs (like ibuprofen). These agents are hepatotoxic as they are metabolized by the liver. If a medication that harms the liver is still recommended by a doctor, the dosage can be adjusted to aim for minimal stress on the liver.
Sources: en.wikipedia.org
Endoskeletons are the internal support structure of an animal, composed of mineralized tissues, such as the bone skeletons found in most vertebrates. Endoskeletons are highly specialized and vary significantly between animals. They vary in complexity from functioning purely for support (as in the case of sponges), to serving as an attachment site for muscles and a mechanism for transmitting muscular forces. A true endoskeleton is derived from mesodermal tissue. Endoskeletons occur in chordates, echinoderms, and sponges.
=== Analytical methods === HMX enters the environment through air, water, and soil because it is widely used in military and civil applications. At present, reverse-phase HPLC and more sensitive LC-MS methods have been developed to accurately quantify the concentration of HMX in a variety of matrices in environmental assessments.
=== Material properties === The molecular weight of this rare amino acid that is found in elastin is 526.611 g/mol. The desmosine pyridinium ring has three allysyl side chains and one unaltered lysyl side chain. It has been tested to show that the pyridinium core of Desmosine remains intact even at very high collision energies.
Sources: en.wikipedia.org
It shares the 44-residue sequence of human GHRH but carries an added trans-3-hexenoyl group at its N-terminus. That addition does not occur in the natural hormone and serves mainly to resist enzymatic breakdown. The receptor target and signaling pathway remain the same.
It binds the growth hormone-releasing hormone receptor on anterior pituitary cells. Activation of that receptor promotes synthesis and release of growth hormone. The effect propagates through the growth hormone and insulin-like growth factor 1 axis.
Native GHRH is cleared quickly by peptidases, which limits how long it can stimulate its receptor. The added group hinders one of the primary cleavage enzymes. The practical consequence is a longer period of receptor activity per dose.
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。