If you have been reading about 长效肽设计 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 2025-09-17. Numbers and descriptions here follow the published literature rather than marketing material.
序列层面的改动同时解决了两个问题，即酶解稳定性与肾脏清除速度。天然 GLP-1 在循环中的半衰期仅约两分钟，主要被二肽基肽酶-4 迅速灭活。酰化侧链与白蛋白的可逆结合形成循环储库，使分子缓慢释放并持续激活受体。这种设计思路后来被广泛用于同类长效肽的开发，属于该类药物化学改造的典型范式。
Semaglutide 是一种经结构修饰的胰高血糖素样肽-1 类似物，其主链与内源性 GLP-1(7-36) 约有百分之九十四的序列一致性。第 8 位丙氨酸被 α-氨基异丁酸取代，使二肽基肽酶-4 无法识别原有切割位点。第 34 位赖氨酸换为精氨酸，进一步降低酶解速率。第 26 位赖氨酸经间隔基连接一条含十八个碳的二酸脂肪链，该侧链赋予分子与血浆白蛋白结合的能力。
该分子作为 GLP-1 受体的选择性激动剂发挥作用，受体属于 B 类 G 蛋白偶联受体家族，激活后经 Gs 通路提升细胞内环腺苷酸水平。在胰腺 β 细胞，信号促进葡萄糖依赖性的胰岛素释放，血糖偏低时该作用明显减弱。在胰岛 α 细胞，胰高血糖素分泌受到抑制。中枢神经系统与胃肠道同样存在受体表达，相应信号参与食欲调节以及胃排空速率的降低。
Lyophilised material appears as a white to off-white cake or powder that is hygroscopic, and containers are usually equilibrated to room temperature before opening to limit condensation. Dissolution is performed in water, phosphate-buffered saline, or a mildly alkaline buffer, since solubility rises above neutral pH. Gentle inversion or low-speed mixing is preferred, because vigorous vortexing can promote surface denaturation and aggregation. Complete dissolution may require several minutes, and brief sonication is sometimes applied. Passing the solution through a 0.22 micrometre membrane removes particulates but does not by itself sterilise the liquid.
Storage at minus 20 degrees Celsius or lower in a desiccated container preserves the peptide for extended periods, while working solutions are commonly held at two to eight degrees Celsius for short intervals. Light exposure and repeated freeze-thaw cycles accelerate degradation, so dividing material into single-use aliquots is generally recommended. Adsorption to glass and plastic surfaces can lower the measured concentration of dilute solutions, particularly below one milligram per millilitre. The degradation routes most often reported for GLP-1 analogues are deamidation, methionine oxidation, and backbone hydrolysis. Relative rates under specific conditions are frequently described only for individual formulations.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 or 280 nanometres is widely used to assess purity and to resolve related impurities. Liquid chromatography coupled to mass spectrometry confirms identity through the protonated molecular ion and fragment ions formed in tandem experiments. Capillary electrophoresis and peptide mapping after enzymatic digestion supply complementary information on charge variants and modification sites. Circular dichroism and nuclear magnetic resonance can report on secondary structure in solution. Absolute quantification usually depends on an external standard, and reported purity depends on the detection wavelength and integration parameters chosen.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C187H291N45O59 | 按主链与 C18 二酸侧链计算 |
| 分子量 | 约 4113.6 道尔顿 | 游离碱形式，随反离子略有差异 |
| 外观 | 白色至类白色冻干粉末 | 具吸湿性，需干燥保存 |
| 溶解性 | 微溶于水，易溶于碱性缓冲液 | 溶解性随 pH 升高而改善 |
| 等电点 | 约 5.4 | 影响缓冲液选择与聚集倾向 |
Pharmacological activity arises from agonism at the glucagon-like peptide-1 receptor, a G protein-coupled receptor expressed in the pancreas, the gastrointestinal tract, and the brainstem. Receptor activation raises intracellular cyclic adenosine monophosphate and enhances insulin release in a glucose-dependent manner, an effect that diminishes when blood glucose concentration is low. Other effects include slowed gastric emptying and hypothalamic satiety signalling. These pathways are described well. Receptor desensitisation rates across tissues, relative to the endogenous hormone, are still under investigation, and reported findings differ between laboratories.
The company that developed the compound filed it as a long-acting analogue, and it gained first approval in 2017 for type 2 diabetes. Later authorisations from several regulators extended the indication to chronic weight management, and the World Health Organization added the glucagon-like peptide-1 receptor agonist drug class to its model list of essential medicines in 2023. Production uses solid-phase peptide synthesis followed by side-chain conjugation and chromatographic purification. Supply constraints and cost differences across regions are well documented. Literature on long-term outcomes continues to grow, with many trials reporting surrogate endpoints rather than hard clinical endpoints.
Semaglutide is a synthetic peptide of thirty-one amino acids that shares roughly ninety-four percent sequence identity with human glucagon-like peptide-1. Two substitutions resist enzymatic cleavage by dipeptidyl peptidase-4, and a fatty diacid side chain attached through a linker promotes binding to serum albumin. That albumin binding slows renal clearance and extends the circulating half-life from minutes to approximately one week. The structural changes are well established in the published literature. Whether the same modifications affect receptor signalling bias in ways that matter clinically remains an open question.
Receptor activation raises intracellular cyclic AMP through Gs coupling, which promotes glucose-dependent insulin release and suppresses glucagon secretion when blood glucose is elevated. Effects outside the pancreas include slower gastric emptying and altered appetite signalling in the hypothalamus and hindbrain. The relative contribution of each tissue to overall metabolic outcomes remains an area of active investigation. Central mechanisms in particular are inferred mainly from animal models and indirect human measures rather than direct observation.
Serum protein binding dominates the pharmacokinetic profile. The attached chain associates strongly with albumin, shielding the peptide from enzymatic attack and slowing filtration by the kidney. This interaction extends the circulation half-life to roughly one week in humans, which supports weekly administration intervals. An oral version pairs the peptide with an absorption enhancer that transiently alters gastric epithelium, permitting limited uptake; bioavailability by that route is substantially lower than by injection.
Semaglutide belongs to the glucagon-like peptide-1 receptor agonist class, a group of synthetic peptides that imitate an incretin hormone released by intestinal L cells after food intake. Native GLP-1 circulates for only a few minutes because dipeptidyl peptidase-4 cleaves it rapidly. The hormone acts on pancreatic islets, the gastrointestinal tract, and several brain regions. Because the natural peptide is short-lived, development work concentrated on analogues that keep receptor activity while resisting enzymatic breakdown and renal clearance.
Semaglutide dissolves readily in water and in aqueous buffers near neutral pH. Solubility decreases near the isoelectric point, where net charge is minimal. Common laboratory solvents include phosphate-buffered saline and dilute ammonium bicarbonate. Strongly acidic or basic conditions may accelerate hydrolysis. Working concentrations are usually prepared by diluting a concentrated stock. Vial surfaces can adsorb small amounts of peptide at low concentrations, so carrier proteins or low-binding tubes are sometimes used.
Reverse-phase high-performance liquid chromatography is the standard method for purity assessment, separating the peptide from truncated or oxidized variants. Mass spectrometry confirms molecular mass and detects modifications, while ultraviolet absorbance near 280 nanometers supports concentration measurement through tryptophan and tyrosine residues. Circular dichroism can indicate secondary structure, though the peptide is largely helical in solution, and ion-exchange chromatography resolves charge variants. Purity values above 95 percent are typical for research-grade material. Stability studies track degradation over time under defined conditions.
== Sterilization of Women Living With HIV in Latin America == Forced and coerced sterilization of Latina women is not limited to the United States; it is an internationally recognized human rights violation. In Latin America, women living with HIV have reported being pressured or coerced into sterilization by healthcare providers. A 2015 study by Kendall and Albert conducted qualitative analysis of reports of how and when healthcare providers pressured women living with HIV in Latin America to be sterilized. They also assessed whether social, economic or fertility history characteristics were associated with the pressure to sterilize. Researchers found that approximately 23% of the women living with HIV reported experiencing pressure to undergo sterilization after their diagnosis. Those who were pregnant while both themselves and their healthcare providers were aware of their HIV status were nearly six times more likely to face coerced or forced sterilization compared to those who were not pregnant with a known diagnosis. Participants reported that some healthcare providers suggested an HIV diagnosis limited their ability to make decisions about having children or choosing contraception. In some cases, physicians were reported to have provided misleading information about related pregnancy risks or withheld services intended to prevent mother-to-child HIV transmission in order to pressure women into sterilization. Reports also indicated that forced sterilizations sometimes occurred during caesarean deliveries.
==== Metabolism ==== Gepirone is metabolized primarily by CYP3A4. Its major metabolites are 1-PP and 3'-OH-gepirone, both of which are pharmacologically active. These metabolites are present in the circulation at higher concentrations than gepirone.
==== Chile ==== Cider has been made in Chile since colonial times. Southern Chile accounts for nearly all cider production in the country. Chileans make a distinction between "sidra" ("cider"), in fact, sparkling cider, and "chicha de manzana" ("apple chicha"), a homemade cider that is considered of less quality.
Sources: en.wikipedia.org
=== Gower 1959 and Coventry 1964 === Heseltine contested the safe Labour seat of Gower at the October 1959 general election. He had been the only applicant for the Conservative (technically, Conservative and National Liberal) candidacy. He would at times attend Labour meetings and attempt to heckle the speakers, including Aneurin Bevan and the Labour candidate Ifor Davies, whom he kept trying to challenge to a debate. He obtained plenty of publicity in the local paper and obtained a swing to the Conservatives slightly better than the national average. In 1961 Heseltine was one of 29 applicants—of whom half were interviewed—for the Conservative candidacy in the marginal constituency of Coventry North. He clinched the selection after bringing his fiancée Anne Williams to the meeting. He got on well with the incumbent Labour member Maurice Edelman (whose daughter was a friend of Anne Heseltine, as she became in 1962) and they met for dinner sometimes during the campaign. Many of his Oxford contemporaries had already entered Parliament, but, to his disappointment, in the 1964 general election he was defeated by 3,530 votes. The swing to Labour was slightly less than the national average.
=== Collection and purification === Due to its extreme lethality, as well as it being only commercially available at certain times and then at an extremely high cost, Amanita phalloides had to be retrieved from the wild in order to collect the β-Amanitin protein. This was first achieved by collecting A. phalloides fruiting bodies in New Jersey in 1975. These mushrooms were then dried for 24 hours and then ground in a blender with water. The slurry created was homogenized further to break open any intact cells, and after this a brown syrup extract containing the toxins was collected. This extract was then taken through various separation methods to isolate the toxins themselves. The toxins were then desalted and taken through four different methods of sephadex and acidic protein purification.
== Early life and education == Badu-Tawiah is from rural Ghana. He was one of three graduates of a high school class of 500 that went on to attend university. He earned his bachelor's and master's degree at the Kwame Nkrumah University of Science and Technology. In 2005 he moved to the United States, where he joined the laboratory of R. Graham Cooks at Purdue University to study high-performance liquid chromatography. There he studied reactions in mass spectrometers, and started to investigate whether this unique environment could be used for synthesis. Whilst at Purdue, Badu-Tawiah was awarded several research fellowships, including the Andrews and Lilly Innovation Fellowships. In 2012 Badu-Tawiah joined Harvard University where he worked in the research laboratory of George M. Whitesides. There he developed paper-based systems capable of performing molecular recognition. In particular, Badu-Tawiah looked to develop macrofluidic platforms that could analyse for specific biomarkers. Unfortunately, the enzymes required to detect biomarkers on paper-based platforms are not stable and require careful storage.
Wolpoff, anthropologist of the University of Michigan; John Shea (archaeologist), anthropologist of Stony Brook University; Lewis Binford, anthropologist of Southern Methodist University in Texas; Neanderthals are thought to have lived similar unevolved uncultured lives for 200,000 years; Brigitte Delluc of Abri Pataud; in the 1980s, a completely new paradigm was thought up by British anthropologist Chris Stringer whereby a new group originated about 200,000 years ago, replacing the former human evolution, known as recent African origin of modern humans, but this paradigm was countered by Milford Wolpoff and his multiregional origin of modern humans, arguing that Neanderthals hadn't died out; Dorothy Garrod, the first female professor at the University of Cambridge in 1939 - the Disney Professor of Archaeology, completed important research in the middle East on how Neanderthals would have encountered much more culturally advanced modern humans in that region; archaeologist Ofer Bar-Yosef described how radiocarbon dating does not work beyond 50,000 years, and modern humans were found there at least 100,000 years ago; the dating methods remained in dispute until reliable genetic ancestry methods arrived in the late 1980s, with Mark Stoneking, a molecular anthropologist of Penn State University, who introduced the Mitochondrial Eve theory in 1987; geneticist Kenneth Kidd and how genetic data had superseded much of the anthropological research, which had been inherently unreliable due to not enough solid data; essentially Neanderthals died out possibly due to insufficient language ability, and were less able in overall cognitive planning. Directed by Lawrence Simanowitz, narrated and produced by William Woollard, made by InCA Productions 6 October Staying Alive, survivors of terrible accidents speak, with Sylvia Chapell of the August 1985 British Airtours Flight 28M; Paul Barney of the September 1994 Sinking of the MS Estonia; survival cognitive psychologist John Leach of Lancaster University; Robert Sapolsky, a neuroendocrinologist, on how glucocorticoids are secreted; Jeffrey Alan Gray, Professor of Psychology at the Institute of Psychiatry, Psychology and Neuroscience; the 336th Training Group at Fairchild Air Force Base; medical researchers at DRDC Toronto; the October 1991 Operation Boxtop 435 Transport and Rescue Squadron from CFB Trenton Hercules crash, which resulted in the 1993 film Ordeal in the Arctic; the brain neurotransmitters affect survival outcomes, controlled by the enzyme monoamine oxidase; Helicopter Underwater Escape Training at Survival Systems in Dartmouth, Nova Scotia. Narrated by Bill Paterson, the consultant was Edward Bullmore, directed by Denman Rooke, produced by Adam Bullmore, made by October Films 13 October Killer Bees, about a catastrophic genetic experiment in southern Brazil in the late 1950s - the Africanized bee; the East African lowland honey bee was introduced in 1956 by Warwick Estevam Kerr; the bees were introduced to help the honey industry, instead the new bees killed off the native bees, as well as many people too, with bees terrorising Apache Junction, Arizona; one swarm of thousand led to 20,000 other swarms in one year; the bees have killed over 600 people; a climber in Costa Rica disturbed a swarm, and received 8,000 stings, killing him. Directed by Martin Gorst, made by Windfall Films 27 October Double Identity, largely about the nature versus nurture argument, as opposed to the less-scientific tabula rasa argument; the Twins Days annual festival held in Twinsburg, Ohio; the heritability of IQ and Robert Plomin of the Institute of Psychiatry, Psychology and Neuroscience at King's College London; Nick Martin of the Queensland Institute of Medical Research; 75% of intelligence is genetic from twin studies, and David T. Lykken of the University of Minnesota; vanishing twins; Neil Sebire of King's College Hospital and Alessandra Piontelli of the University of Milan; country music The LeGarde Twins; Dorothy V. M. Bishop of the University of Cambridge; heritability of IQ and Peter Conrad (sociologist) of Brandeis University; the Louisville Twin Study at the University of Louisville in Kentucky, which also found the Scarr–Rowe effect. Narrated by Jenni Murray, directed by Selina Macnair, produced by Amanda Theunissen, made by Fulcrum Productions West 3 November Identified Flying Objects, about Marfa, Texas and the Marfa lights, and other earthquake lights; Paul Devereux and computer scientist Erling Strand, of Østfold University College and Project Hessdalen, visits the Min Min lights in Australia in 1995; Paul Devereux investigated lights that had been seen at Llanegryn in 1904, which followed the Mochras geological fault; there had been seismic activity at the time which had culminated in the 1906 Swansea earthquake; lights had been seen at Toppenish ridge in the US, in the Cascade Mountains, which had a thrust fault; geologist Peter Sammonds at the UCL Department of Earth Sciences; geophysicist Jim Byerlee, known for Byerlee's law; Mexican television presenter Jaime Maussan; the Popocatépetl volcano in Mexico. Narrated by David Jessel, directed by Chris Hale, made by Real World Pictures, with the Discovery Channel 10 November What's in a Number?, poetry by Lavinia Greenlaw, with dyscalculia which is connected to the parietal lobe and Prof Brian Butterworth of UCL Neuroscience; the artist Sir Michael Craig-Martin; a 1950s educational film about pi made by Coronet Films; the Chudnovsky brothers; fractals come from plotting on a graph imaginary numbers against real numbers and have self-similarity, and Ian Stewart of the University of Warwick; Steven Weinberg of the University of Texas at Austin. Directed by Edmund Coulthard, produced by Duncan Dallas, who founded Café Scientifique in 1998, made by XYTV 24 November The Men with Nine Lives, about the British Army bomb disposal course, with 321 EOD Squadron RLC and the Army School of Ammunition (now the Defence Explosive Ordnance Disposal, Munitions and Search Training Regiment); twenty British Army bomb disposal personnel were killed defusing bombs in Northern Ireland; early IRA explosives were in tin cans filled with nails; 42-year-old Shane O'Doherty, a former IRA operative, who received thirty life sentences in 1974 for letter bombs; IRA personnel called themselves 'explosive operatives'; the IRA moved on to bombs in mail packages, triggered by tilt switches, and on to much-bigger car bombs; Lieutenant-Colonel Peter Miller invented a remote-control mechanical device that could set off a controlled explosion, so disabling most of the bomb components; projected water disruptors could remove explosive devices under vehicles; the IRA put car explosive devices inside a half of a beer keg; letter bombs would contain three to four ounces of semtex (mostly pentaerythritol tetranitrate); the Downing Street mortar attack of 7 February 1991; the hostage bomb; the IRA would lure army bomb disposal personnel, and metal-detectors would find how the IRA had lured army personnel; south Armagh, controlled by the Provisional IRA South Armagh Brigade was the most-dangerous part of Northern Ireland, and all army personnel travelled on operations only by helicopter. Directed by David Dugan, made by Windfall Films. Shown on Nova on 21 October 1997 as Bomb Squad 1 December Day Return to Space about the new proposals for craft; in 1995, NASA proposed the X-33, chosen on 2 July 1996, to fly by March 1999; Daniel Goldin, head of NASA from 1992 to 2001; Saturn from The Planets; The Blue Danube; the McDonnell Douglas DC-X; Maxwell Hunter; Jupiter from The Planets; Hans Mark of NASA; David Urie and Paul Landry; the Rutan Voyager, which flew around the world without refuelling; the aerospike engine; the Ansari X Prize and the EAA AirVenture Oshkosh air show; Mitchell Burnside Clapp; Gary Hudson, Bevin McKinney, and their Rotary Rocket (Roton); Steve Bennett and his Starchaser Industries. Narrated, similarly to the Adam Curtis series, by Jack Fortune, produced by Richard Reisz, directed by Stephen White, made by TV6 8 December Superhighway Robbery, about 26-year-old Russian computer programmer Vladimir Levin and computer hacking, who was caught when he arrived at Stansted Airport in March 1995 (he was trying to evade extradition to the US, but failed and was extradited in September 1997; an average bank robbery took $1900, but was prosecuted around 82%, a robbery via computer took around $250,000 and prosecution was around 2%; Willie Sutton and his Sutton's law. Narrated by Robin Ellis, directed by Patrick Forbes, produced by Jenny Crowther, made by Hart Ryan. 15 December Dr Satan's Robot, it refers to the film Mysterious Doctor Satan; it shows surgeon Robert J. White and his many macabre experiments on animals; the documentary would have not been appointment viewing for supporters of PETA; John Frankenheimer, director of the film Island of Dr Moreau; Terry Gilliam and his film Twelve Monkeys; the film The City of Lost Children; novelist Michael Marshall Smith, and his novel Spares; Cold Lazarus by Dennis Potter; Conservative MP for Birmingham Edgbaston, Jill Knight, and her disagreements with Roger Gosden; John Gillott; film director John Carpenter; David King, and disagreements with Robert Plomin, which led to his MRC funding being withheld; James Wilson (scientist) of the Perelman School of Medicine at the University of Pennsylvania; Julliet Tizzard of the Progress Trust. Narrated by Seán Barrett (actor), produced by Cathy Rogers, directed by Martin Durkin, made by RDF Television, with the Learning Channel
Sources: en.wikipedia.org
差别集中在三处：第 8 位残基被非天然氨基酸取代，第 34 位换成精氨酸，第 26 位增加一条脂肪酸侧链。前两处改动降低酶解速率，侧链则通过白蛋白结合延长循环时间。综合结果是半衰期从约两分钟延长到约一周。
胰岛素释放需要细胞内环腺苷酸与钙信号升高，同时依赖葡萄糖代谢产生的协同信号。血糖水平较低时协同信号不足，分泌增强有限。这一机制在降糖效果与低血糖风险之间提供了缓冲。
白蛋白结合是主要原因，它减少肾小球滤过并保护分子免受蛋白酶降解。序列修饰带来的酶解抵抗同样不可忽略，二者共同作用。脂肪链的疏水性还会影响组织分布，但其对总半衰期的贡献程度仍在研究之中。
Filtering removes particulate matter that can block columns or scatter light. A 0.22 micrometre membrane is typical, and the filter material should be checked for peptide adsorption.