A practical reference on receptor agonist: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-09-17 and is reviewed periodically as new material appears.
Two principal therapeutic variants exist under separate regulatory filings, one indicated for glycemic control in type 2 diabetes and one for chronic weight management. Both use the same active molecule; differences lie in formulation strength, titration schedule, and labeling. Regulatory agencies in the United States and European Union approved injectable forms in 2017 and 2018 respectively. An oral tablet formulation received approval later, using a carrier molecule to enhance absorption across the gastric epithelium. Labeling differs by jurisdiction and by indication.
The distinction between established facts and open questions matters here. That the peptide binds the GLP-1 receptor and stimulates insulin release in a glucose-dependent manner is well documented. How individual variability in receptor density, gastric emptying rate, and gut microbiome composition shapes response remains an active research area. Long-term outcomes beyond five years of continuous use are not yet fully characterized in published trials, and several extension studies are ongoing.
Semaglutide is a synthetic peptide analog of glucagon-like peptide-1, a hormone released from intestinal L cells after food intake. The molecule is a 31-amino-acid backbone modified at three positions to resist cleavage by dipeptidyl peptidase-4, the enzyme that degrades native GLP-1 within minutes. A lysine residue at position 26 carries a linker and a C18 fatty diacid, which promotes binding to serum albumin and slows renal clearance. These changes extend the circulating half-life from roughly two minutes to about one week in humans.
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。
皮下注射后吸收相对缓慢,绝对生物利用度约为百分之八十九,血药浓度峰值通常出现在给药后一到三天。与白蛋白结合使清除减慢,终末半衰期约为一百六十五小时,接近一周。连续给药约四到五周后达到稳态暴露水平。表观分布容积约为每千克零点二五升,血浆蛋白结合率超过百分之九十九。代谢以蛋白水解切割和脂肪二酸侧链的 β-氧化为主,相关产物主要经尿液与粪便排出。
| Property | Value | Notes |
|---|---|---|
| Molecular formula (free base) | C187H291N45O59 | Approximate; salt and hydrate forms differ |
| Molecular weight | ~4113.6 Da | Varies with counterion and hydration |
| Appearance | White to off-white powder | Lyophilized research material |
| Solubility class | Freely soluble in water | As formulated; native peptide less stable near neutral pH |
| Typical storage | 2 to 8 degrees Celsius | Protect from light; avoid repeated freeze-thaw |
Three structural changes define the molecule. At position 8 an alpha-aminoisobutyric acid residue replaces alanine, which blocks dipeptidyl peptidase-4 cleavage. At position 34 arginine replaces lysine, and at position 26 a lysine carries a C18 fatty diacid attached through a short linker. The fatty chain binds serum albumin, and this albumin association reduces renal filtration and enzymatic attack. The unchanged backbone retains the receptor contacts that produce signalling. The free base has the formula C187H291N45O59 and a molecular weight near 4114 daltons.
Receptor activation follows the canonical Gs pathway: binding increases intracellular cyclic AMP, which promotes protein kinase A activity. In pancreatic beta cells this amplifies glucose-dependent insulin release, so secretion rises when blood glucose is high and changes little when it is low. The same signalling suppresses glucagon release from alpha cells and slows gastric emptying. Receptors in the hypothalamus and brainstem are thought to contribute to reduced appetite and lower energy intake. Which of these effects dominates clinical outcomes remains an area of active study.
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released by intestinal L cells after food intake. The natural hormone acts on pancreatic and central receptors but is degraded within minutes by dipeptidyl peptidase-4 and other peptidases. Semaglutide belongs to the class of long-acting GLP-1 receptor agonists, a group distinguished by structural changes that slow breakdown and extend circulation time. Its development followed earlier short-acting analogues and reflects a general strategy in peptide drug design: preserve receptor activity while blocking proteolytic clearance.
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.
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.
Clinical development of this compound followed earlier short-acting GLP-1 analogues that required frequent injection. Once-weekly subcutaneous formulations entered use after 2017, and an oral formulation using a permeation enhancer later became available. The oral version pairs the peptide with sodium N-(8-[2-hydroxybenzoyl] amino) caprylate, a carrier that improves uptake across the gastric epithelium. Interest has expanded from glycaemic control into weight management and metabolic liver disease. Regulatory status and approved indications differ between countries, and the product remains subject to ongoing safety monitoring.
Semaglutide is a synthetic peptide that acts as an agonist at the glucagon-like peptide-1 receptor. It is a structural analogue of human GLP-1(7-37), modified to resist enzymatic degradation by dipeptidyl peptidase-4. The peptide backbone contains alpha-aminoisobutyric acid at position 8, a substitution that stabilises the helix and slows cleavage. A fatty diacid side chain attached through a linker at lysine 34 promotes binding to serum albumin, which extends the circulating half-life. These two modifications together allow less frequent administration than native GLP-1 requires.
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.
== Nutrition == Sake kasu is a highly nutritious by-product of sake providing protein, carbohydrates, fat, vitamins (including some B vitamins), fiber, ash, peptides, and amino acids. It has also been found that sake kasu has the potential to reduce the risk of non-alcoholic fatty liver disease (NAFLD) and an extract has potential to be used as a treatment. According to a science television program, "Tameshite Gatten", that aired on NHK in Japan, it was explained that the fiber and resistant protein in sake kasu can reduce low-density lipoprotein cholesterol levels and amino acids. Whether sake kasu is heat-dried or freeze-dried, there is little difference in nutritional value between the two drying methods. With heat-dried sake kasu there are more free amino acids, whereas the freeze-dried sake kasu contains more S-adenosyl methionine. The degradation of microbial metabolites during heat-drying sake kasu can cause an increase in the amount of nucleic acid-related components. When feeding aging mice with sake kasu, the branched-chain amino acid level is high in different parts of the mice including the plasma, brain, and muscle. Based on the experiment, it is believed that consuming sake kasu may be beneficial towards the elderly in maintaining brain tissue and motor functions. Fermented sake kasu is produced by introducing lactic acid bacteria to the sake kasu during the fermentation process. Consuming fermented sake kasu can suppress type I allergic reaction and allergic rhinitis-like symptoms.
After his release from jail, Colonel Rhodes immediately joined his brother Cecil and the British South Africa Company in the Second Matabele War taking place just north of the Transvaal in Matabeleland. Cecil Rhodes was forced to resign as Prime Minister of Cape Colony in 1896 due to his apparent involvement in planning and assisting in the raid; he also, along with Alfred Beit, resigned as a director of the British South Africa Company. Jameson's raid had depleted Matabeleland of many of its troops and left the whole territory vulnerable. Seizing on this weakness, and a discontent with the British South Africa Company, the Ndebele revolted during March 1896 in what is now celebrated in Zimbabwe as the First War of Independence, the First Chimurenga, but it is better known to most of the world as the Second Matabele War. The Shona joined them soon thereafter. Hundreds of European settlers were killed within the first few weeks of the revolt and many more would die over the next year and a half. With few troops to support them, the settlers had to quickly build a laager in the centre of Bulawayo on their own. Against over 50,000 Ndebele held up in their stronghold of the Matobo Hills the settlers mounted patrols under such people as Burnham, Baden-Powell, and Selous. It would not be until October 1897 that the Ndebele and Shona would finally lay down their arms.
The topic of IAQ has become popular due to the greater awareness of health problems caused by mold and triggers to asthma and allergies. In the US, the Environmental Protection Agency (EPA) has developed an "IAQ Tools for Schools" program to help improve the indoor environmental conditions in educational institutions. The National Institute for Occupational Safety and Health conducts Health Hazard Evaluations (HHEs) in workplaces at the request of employees, authorized representative of employees, or employers, to determine whether any substance normally found in the place of employment has potentially toxic effects, including indoor air quality. A variety of scientists work in the field of indoor air quality, including chemists, physicists, mechanical engineers, biologists, bacteriologists, epidemiologists, and computer scientists. Some of these professionals are certified by organizations such as the American Industrial Hygiene Association, the American Indoor Air Quality Council and the Indoor Environmental Air Quality Council. In the UK, under the Department for Environment Food and Rural Affairs, the Air Quality Expert Group considers current knowledge on indoor air quality and provides advice to government and devolved administration ministers. At the international level, the International Society of Indoor Air Quality and Climate (ISIAQ), formed in 1991, organizes two major conferences, the Indoor Air and the Healthy Buildings series.
Sources: en.wikipedia.org
=== Foreign policy === Moore supports Israel's right to defend itself and a two-state solution to the Israeli–Palestinian conflict. In December 2022, he attended the Jewish Community Relations Council of Greater Washington's legislative breakfast, where he said he would be "very aggressive" in promoting trade between Maryland and Israel and promised that one of his first overseas visits would be to Israel. He expressed solidarity with Israel amid the October 7 attacks, and later supported an immediate ceasefire in the Gaza war. In October 2024, Moore criticized a Students for Justice in Palestine event at the University of Maryland, College Park held on the one-year anniversary of the October 7 attack to honor Palestinian civilians killed in the Gaza war, saying that he felt that it was an "inappropriate date for such an event". In May 2026, Moore told Politico that he believed Israeli Prime Minister Benjamin Netanyahu had committed war crimes in the Gaza war, citing his use of food as a negotiating tool. In April 2026, Moore criticized U.S. involvement in the 2026 Iran war, likening it to the war in Afghanistan and fearing it would evolve into "another forever war". He also criticized President Donald Trump for not clearly addressing the American people on what the U.S. is doing in Iran or what success looks like.
UPMC Kildare Hospital is a 39-bed private hospital located in County Kildare, Ireland (founded in 1985 as Clane General Hospital). UPMC acquired the hospital in November 2019 in partnership with the Institute of Eye Surgery.
This reaction was hailed as a "revolution" and essentially started the distinct field of synthetic peptide chemistry. It remained unsurpassed in utility for peptide synthesis until the early 1950s when mixed anhydride and active ester methodologies were developed. Although the reaction is no longer commonly used for peptides, it is nonetheless very widespread for amine protection in other applications within organic synthesis and total synthesis. Common procedures to achieve protection starting from benzyl chloroformate include:
Cardiac fibroblasts are vital supporting cells within cardiac muscle. They are unable to provide forceful contractions like cardiomyocytes, but instead are largely responsible for creating and maintaining the extracellular matrix which surrounds the cardiomyocytes. Fibroblasts play a crucial role in responding to injury, such as a myocardial infarction. Following injury, fibroblasts can become activated and turn into myofibroblasts – cells which exhibit behaviour somewhere between a fibroblast (generating extracellular matrix) and a smooth muscle cell (ability to contract). In this capacity, fibroblasts can repair an injury by creating collagen while gently contracting to pull the edges of the injured area together. Fibroblasts are smaller but more numerous than cardiomyocytes, and several fibroblasts can be attached to a cardiomyocyte at once. When attached to a cardiomyocyte they can influence the electrical currents passing across the muscle cell's surface membrane, and in the context are referred to as being electrically coupled, as originally shown in vitro and in the 1960s, and ultimately confirmed in native cardiac tissue with the help of optogenetic techniques. Other potential roles for fibroblasts include electrical insulation of the cardiac conduction system, and the ability to transform into other cell types including cardiomyocytes and adipocytes.
Sources: en.wikipedia.org
The Meeting of Teano between Garibaldi and King Victor Emmanuel II of Savoy took place on 26 October 1860, where he annexed Mezzogiorno. On 19 August 1860, Calabria was invaded from Sicily by Giuseppe Garibaldi and his Redshirts as part of the Expedition of the Thousand. Through King Francesco II of Naples had dispatched 16,000 soldiers to stop the Redshirts, who numbered about 3,500, after a token battle at Reggio Calabria won by the Redshirts, all resistance ceased and Garibaldi was welcomed as a liberator from the oppressive rule of the Bourbons wherever he went in Calabria. Calabria together with the rest of the Kingdom of Naples was incorporated in 1861 into the Kingdom of Italy. Garibaldi planned to complete the Risorgimento by invading Rome, still ruled by the pope protected by a French garrison, and began with semi-official encouragement to raise an army. Subsequently, King Victor Emmanuel II decided the possibility of war with France was too dangerous, and on 29 August 1862 Garibaldi's base in the Calabrian town of Aspromonte was attacked by the Regio Esercito. The Battle of Aspromonte ended with the Redshirts defeated with several being executed after surrendering while Garibaldi was badly wounded. With the plebiscite of 21 October 1860, Calabria and the other southern provinces became part of the Kingdom of Sardinia: consequently, elections were called to allow the newly annexed territories to select representation in Parliament. The election was held on 27 January 1861, and the new Parliament was inaugurated in Turin on February 18.
Bimagrumab (BYM338) is a human monoclonal antibody first developed by Novartis and currently by Eli Lilly to treat pathological muscle loss and weakness. It binds to and inhibits activin receptor type-2B. Bimagrumab must be administered intravenously at a hospital or clinic. The medication has a long half-life and is administered once a month.
=== Category:EC 1.13 (act on single donors with incorporation of molecular oxygen) === Category:EC 1.13.11 (With incorporation of two atoms of oxygen) 4-hydroxyphenylpyruvate dioxygenase (EC 1.13.11.27) Category:EC 1.13.12 (With incorporation of one atom of oxygen (internal monooxygenases or internal mixed function oxidases)) Renilla-luciferin 2-monooxygenase EC 1.13.12.5 Cypridina-luciferin 2-monooxygenase EC 1.13.12.6 Firefly luciferase EC 1.13.12.7 Watasenia-luciferin 2-monooxygenase EC 1.13.12.8 Oplophorus-luciferin 2-monooxygenase EC 1.13.12.13
==== Sublabial ==== Sublabial administration is achieved by placing the drug between the lip and gum. The frenulum of the tongue may be irritated when in contact with corrosive materials but can be avoided with this route. It is usually used for medications such as nitroglycerin, for example.
== Awards and fellowships == 1984 ACS Analytical Division's Chemical Instrumentation Award; 1985 Thomson Medal for International Service to Mass Spectrometry; 1990 and 1995 NSF Special Creativity Award; 1991 Frank H. Field & Joe Franklin Award, (ACS Award for Mass Spectrometry); 1997 Fisher Award (ACS Award for Analytical Chemistry); 2006 Distinguished Contribution in Mass Spectrometry Award; 2008 Robert Boyle Prize for Analytical Science; 2012 F.A. Cotton Medal for Excellence in Chemical Research of the American Chemical Society; 2013 Dreyfus Prize in the Chemical Sciences; 2014 ACS Nobel Laureate Signature Award for Graduate Education in Chemistry, shared with graduate student Livia S. Eberlin; 2015 Member, National Academy of Sciences; 2017 Aston Medal, British Mass Spectrometry Society.
Sources: en.wikipedia.org
It is a modified version of the natural hormone, with three amino acid changes and a fatty acid side chain added. These edits extend its half-life from minutes to about one week. The core receptor activity is retained.
Both deliver the same active peptide and act on the same receptor. The tablet includes an absorption enhancer because peptides are poorly taken up intact from the gut. Bioavailability of the oral route is substantially lower, so the two are not dose-equivalent.
No, it is entirely synthetic and does not occur in nature. Native GLP-1 is produced in the gut and pancreas, but the analog is manufactured by chemical synthesis or recombinant methods. Traces of the analog are not expected in people who never received it.
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。