This is a working overview of somatotroph, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-07-21 and is reviewed periodically as new material appears.
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。
作用位置在垂体前叶。tesamorelin 与 GHRH 受体结合后激活腺苷酸环化酶,升高细胞内 cAMP,再经蛋白激酶 A 通路促进生长激素的合成与释放。由于它作用于内源调控节点,生长激素仍以脉冲方式分泌,而不是被持续抬升到固定水平。生长激素随后在肝脏等组织诱导胰岛素样生长因子 1 产生,构成完整的生长激素轴响应。
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.
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.
| 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 |
Development work on the compound, originally designated TH9507, focused on conditions in which reduced growth hormone signaling is thought to contribute to altered body composition. The United States Food and Drug Administration approved it in 2010 for the treatment of excess visceral abdominal fat in adults with human immunodeficiency virus infection and lipodystrophy. Later research examined other populations, including adults with mild cognitive impairment, where a large trial did not meet its primary endpoints. This mixed record illustrates how a single mechanism can produce clear effects in one setting and inconclusive results in another.
Several related peptides act on the same receptor, including sermorelin, a shorter GHRH fragment, and modified analogs such as CJC-1295 and modified GRF(1-29) that are common in research settings rather than approved products. Tesamorelin differs from growth hormone itself in that it acts upstream, prompting the pituitary to release the hormone through physiological signaling rather than supplying it directly. Terminology in the literature distinguishes GHRH analogs, growth hormone secretagogues, and recombinant growth hormone, although popular discussion often blurs these categories together. Precise naming matters when comparing study results.
Tesamorelin is a synthetic peptide of 44 amino acids that reproduces the sequence of human growth hormone-releasing hormone (GHRH) and carries a trans-3-hexenoyl group on its N-terminal tyrosine. That small fatty-acid modification blocks cleavage by dipeptidyl peptidase-4, the enzyme that rapidly degrades native GHRH in plasma. The result is a molecule with a longer circulating half-life than the natural hormone while retaining the same receptor target. It is supplied as a lyophilized powder for reconstitution and belongs to the broader class of GHRH analogs studied for effects on pituitary growth hormone secretion.
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。
=== Notable alumni === Keith Barry, performing artist Fiona Everard, national champion runner Ethna Gaffney, first female professor at the Royal College of Surgeons in Ireland Michael D. Higgins, 9th President of Ireland Catherine Connolly, 10th President of Ireland Enda Kenny, former Taoiseach Aifric Keogh and Fiona Murtagh Olympic bronze medalists Tokyo 2020 Mark Heslin, judge of the High Court Máire Whelan, former Attorney General and current judge of the Court of Appeal Breandán Ó hEithir, writer and author Pat McGrath, news correspondent Wilfrid Napier O.F.M., Cardinal, Archbishop of Durban Conor Pope, journalist Gráinne Seoige, former news anchor and television presenter Martin Sheen, actor Nicola Coughlan, actor Rónán Mullen, Irish senator representing National University of Ireland (constituency) Enya (honorary doctorate) Heather Humphreys, Fine Gael politician Donogh O'Malley, Fianna Fáil politician Bobby Molloy, Fianna Fáil politician Frank Fahey (politician) Pat Rabbitte, former Irish Labour Party leader Séamus Brennan, former Irish government minister Alfred Keogh, former Director-General of the British Army Medical Services during the First World War. Brian McManus, host of the YouTube channel Real Engineering
Other notable mutations identified in ICP patients include ones in the farnesoid X receptor (FXR), a nuclear receptor in hepatocytes which activates transcription of MDR3 and BSEP upon binding intracellular bile acids, thereby increasing canalicular bile efflux.
== March 2013 reconstitution == Following the return of the government at the 2013 state election, held on 9 March, the Ministry was again reconstituted, and was sworn in on 21 March 2013. John Castrilli (Local Government; Heritage; Citizenship and Multicultural Interests) and the retiring Norman Moore (Mines and Petroleum; Fisheries; Electoral Affairs) both resigned their positions, while Simon O'Brien (Finance; Commerce; Small Business), Robyn McSweeney (Child Protection; Community Services; Seniors and Volunteering; Women's Interests; Youth), and Murray Cowper (Training and Workforce Development; Corrective Services) each lost their portfolios. Five new ministers were appointed, including four previous parliamentary secretaries, and seven new parliamentary secretaries were appointed, making eight in total. A new portfolio, that of Minister for Veterans, was created. The list below is ordered by decreasing seniority within the Cabinet, as indicated by the Government Gazette and the Hansard index. Blue entries indicate members of the Liberal Party, while green entries indicate members of the National Party.
=== Low et al 2007 === Low, Wai Yee; Ng, Hooi Ling; Morton, Craig J.; Parker, Michael W.; Batterham, Philip; Robin, Charles (2007). "Molecular Evolution of Glutathione S-Transferases in the Genus Drosophila". Genetics. 177 (3). Genetics Society of America/Oxford University Press (OUP): 1363–1375. doi:10.1534/genetics.107.075838. ISSN 0016-6731. PMC 2147980. PMID 18039872.
Some have argued that it has common features with other self-diagnosed "mystery syndromes" such as Morgellons or multiple chemical sensitivity, while others, including some in the biomedical research community, have concluded based on the available evidence that it represents a real and serious condition. There is no known underlying biological mechanism for the proposed syndrome, and its incidence is unclear. A lack of clear diagnostic criteria and the variable reporting fraction in different healthcare settings make the problem challenging to evaluate. In 2016 Merck was a defendant in approximately 1,370 product liability lawsuits which had been filed by customers alleging they had experienced persistent sexual side-effects following cessation of treatment with finasteride. Most cases had been settled by 2018, when Merck paid a lump sum of US$4.3 million to be distributed. As of September 2019, 25 cases remained outstanding in the United States. In 2019, Reuters reported that faulty redactions in court documents revealed allegations from plaintiffs that Merck had known of persistent side effects in their original clinical trials but chose not to disclose them in warning labels.
Sources: en.wikipedia.org
=== Advantages === Plants do not carry pathogens that might be dangerous to human health. Additionally, on the level of pharmacologically active proteins, there are no proteins in plants that are similar to human proteins. On the other hand, plants are still sufficiently closely related to animals and humans that they are able to correctly process and configure both animal and human proteins. Their seeds and fruits also provide sterile packaging containers for the valuable therapeutics and guarantee a certain storage life. Global demand for pharmaceuticals is at unprecedented levels. Expanding the existing microbial systems, although feasible for some therapeutic products, is not a satisfactory option on several grounds. Many proteins of interest are too complex to be made by microbial systems or by protein synthesis. These proteins are currently being produced in animal cell cultures, but the resulting product is often prohibitively expensive for many patients. For these reasons, science has been exploring other options for producing proteins of therapeutic value. These pharmaceutical crops could become extremely beneficial in developing countries. The World Health Organization estimates that nearly 3 million people die each year from vaccine preventable disease, mostly in Africa. Diseases such as measles and hepatitis lead to deaths in countries where the people cannot afford the high costs of vaccines, but pharm crops could help solve this problem.
== Epidemiology == The National Eye Institute reports keratoconus is the most common corneal dystrophy in the United States, affecting about one in 2,000 Americans, but some reports place the figure as high as one in 500. In the pediatric populations, ages three to 18, the prevalence of keratoconus was found to be as high as one in 334 children. The inconsistency may be due to variations in diagnostic criteria, with some cases of severe astigmatism interpreted as those of keratoconus, and vice versa. A long-term study found a mean incidence rate of 2.0 new cases per 100,000 population per year. Some studies have suggested a higher prevalence amongst females, or that people of South Asian ethnicity are 4.4 times as likely to develop keratoconus as Caucasians, and are also more likely to be affected with the condition earlier. Keratoconus is normally bilateral (affecting both eyes) although the distortion is usually asymmetric and is rarely completely identical in both corneas. Unilateral cases tend to be uncommon, and may in fact be very rare if a very mild condition in the better eye is simply below the limit of clinical detection. It is common for keratoconus to be diagnosed first in one eye and not until later in the other. As the condition then progresses in both eyes, the vision in the earlier-diagnosed eye will often remain poorer than that in its fellow.
Insulin icodec, sold under the brand name Awiqli, is an ultralong-acting basal insulin analogue used in the treatment of diabetes. It is administered by subcutaneous injection once weekly. It was developed by Novo Nordisk. Insulin icodec was designed to provide basal insulin coverage with once-weekly dosing. It is approved for medical use in Canada, the European Union, Australia, and in the United States.
=== Contestants === 1st - Sinai Vespie, Pastry Chef from Mishawaka, Indiana 2nd - Renee Loranger, Pastry Chef from Waveland, Mississippi 3rd - Aaron Clouse, Pastry Chef from Columbus, Ohio 4th - Michelle Lee, Sous Chef from Monterey, California 5th - Michael Gaddy, Pastry Chef from Dade City, Florida 6th - Brian Bosch, Event Designer from Santa Ana, California 7th - Tamara Brown, from Los Angeles, California 8th - Holly Braddock, Pastry Chef from Myrtle Beach, South Carolina 9th - Nerwan Khalife, Pastry Chef from Bronx, New York 10th - Edward Cunningham, Railroad Heavy Equipment Operator from Chicago, Illinois
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。
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.