incretin mimetic 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.
Last reviewed on 2025-09-21. Where a claim depends on a specific study, the study is described rather than over-claimed.
The primary target is the GLP-1 receptor, a class B G protein-coupled receptor expressed on pancreatic beta cells, in the gut, and in several brain regions. Receptor activation raises intracellular cyclic AMP, which potentiates glucose-dependent insulin secretion and lowers glucagon release when blood glucose is elevated. Signalling in the hypothalamus and brainstem is associated with reduced appetite and slower gastric emptying. Because the insulinotropic effect depends on prevailing glucose levels, the hypoglycaemic risk of the peptide alone is described as low in most study settings. The relative contribution of peripheral and central actions remains an active research question.
Large randomised trials in adults with type 2 diabetes and in adults with obesity have reported reductions in body weight and improvements in several cardiovascular risk markers. One outcome trial found a lower incidence of major adverse cardiovascular events in participants with diabetes and established cardiovascular disease. Gastrointestinal effects such as nausea and vomiting are the most frequently reported adverse events and often diminish over time. Changes in lean body mass during weight loss are an area of ongoing investigation. Effects in adolescents and in pregnancy are less well characterised, and current labelling advises against use during pregnancy.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Acylated GLP-1 receptor agonist | 31-residue synthetic peptide |
| Molecular formula | C187H291N45O59 | established for the free peptide |
| Appearance | White to off-white powder | as supplied before formulation |
| Solubility | Freely soluble in water | aqueous buffers near neutral pH |
| Typical storage | 2 to 8 degrees Celsius, protected from light | powder and solution forms differ in shelf life |
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.
Lyophilized semaglutide is typically stored at temperatures between minus 20 and minus 80 degrees Celsius for long-term preservation. Short-term storage at 2 to 8 degrees Celsius is common for working aliquots. Repeated freeze-thaw cycles can degrade the peptide and are usually avoided. The molecule is hygroscopic in its solid form, so containers should remain sealed with desiccant. Solutions are less stable than powders and are generally prepared fresh. Light exposure is limited because aromatic residues can undergo photo-oxidation.
Activation of the GLP-1 receptor couples to Gs signalling and raises intracellular cyclic AMP in pancreatic beta cells. The resulting insulin release depends on prevailing glucose concentrations, so the effect is greater when glucose is elevated. Receptor engagement also suppresses glucagon secretion and slows gastric emptying, which flattens post-meal glucose excursions. In the central nervous system, signalling in hypothalamic and brainstem regions is associated with reduced appetite and lower energy intake. Studies continue to examine effects on cardiac, renal and hepatic endpoints; whether those benefits are independent of weight change remains an open question.
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.
=== United Kingdom === In November 2023, Juniper was among several UK-registered online providers continuing to prescribe Ozempic for weight loss during a national shortage of semaglutide. The Advertising Standards Authority (ASA) issued an advice notice to Juniper over advertisements implying endorsement by National Health Service (NHS) workers. There were concerns about misleading claims and the promotion of prescription-onlu medicines. The ASA launched multiple investigations into online advertising by weight-loss providers, including Juniper. In June 2025, Juniper was among providers examined after test purchases showed weight-loss injections could be obtained following online questionnaires without real-time consultation. In September 2025, the growing private market for GLP-1 weight-loss medications in the UK had raised concerns about a two-tier system of access, with most users paying privately due to limited NHS availability. Juniper was offering private access to weight-loss treatments, while clinicians and public-health experts warned that cost barriers could exacerbate health inequalities and limit access for lower-income patients.
== Applications == In the presence of iron chloride or copper chloride catalyst, or of liquid sulfur at 120 °C Diallyl disulfide can be used as a precursor for the synthesis of higher diallyl polysulfides (polysulfanes). In agriculture, diallyl disulfide and related diallyl polysulfides show useful activity as environmentally-benign nematicides. Diallyl disulfide is also a starting material for the synthesis of allicin. In the food industry, diallyl disulfide is used to improve the taste of meat, vegetables and fruits.
=== Sahrawi Arab Democratic Republic === The Castillo Administration recognized the Sahrawi Arab Democratic Republic, a partially-recognized state claimed by Morocco. Although the recognition came without forewarning, officially it was due to Castillo's push for a foreign policy based on self-determination and non-intervention. The Congressional opposition has opposed the recognition of the SADR, claiming that it creates geopolitical instability and risks Peru's relations with the Middle East.
== Research career and academic posts == After completing graduate school, Fenn's first job was with Monsanto, working in the Phosphate Division and producing polychlorinated biphenyls (PCBs). Fenn and his colleague James Mullen became disenchanted with the direction of work at Monsanto, and they resigned together in 1943. Fenn worked briefly at a small company named Sharples Chemicals that focused on the production of amyl chloride derivatives. In 1945, he joined Mullen at his new startup, Experiment, Inc, focusing on research and development. Fenn's first publication came in 1949 as a result of his work with Mullen. That this publication came ten years after he completed graduate school made Fenn somewhat of a rarity amongst academics. In 1952, Fenn moved to Princeton University as Director of Project SQUID, a program to support research related to jet propulsion that was funded by the Office of Naval Research. During this period, Fenn started his work developing supersonic atomic and molecular beam sources, which are now widely used in chemical physics research. After working with Project SQUID, Fenn returned to Yale University in 1967. He held a joint appointment in the chemistry and engineering departments until 1987, conducting much of his research in Mason Laboratory. In 1987, Fenn had reached Yale's mandatory retirement age. He became a professor emeritus, entitling him to office space at the university, but costing him most of his laboratory space and research assistants.
Local promoter Randy Hauser became aware of the band at a concert and offered to pay for demo recordings. However, one day before the band was due to record at the Music Bank studio in Washington, police shut down the studio during the biggest cannabis raid in the history of the state. The final demo, completed in 1988, was named The Treehouse Tapes and found its way to music managers Kelly Curtis and Susan Silver, who also managed the Seattle-based band Soundgarden. Curtis and Silver passed the demo on to Columbia Records' A&R representative Nick Terzo, who set up an appointment with label president Don Ienner. Based on The Treehouse Tapes, Terzo signed Alice in Chains to Columbia in 1989.
Sources: en.wikipedia.org
== Etymology == The term tempe is thought to be derived from the Old Javanese tumpi, a whitish food made of fried batter made from sago or rice flour which resembles rempeyek. The historian Denys Lombard also suggests that it could be linked to a later term tape or tapai which means 'fermentation'. In the western world, tempeh rather than tempe is the most common spelling, to emphasise that the final "e" is pronounced. The first known usage of this spelling is in an 1896 German article. Other spellings, such as témpé, were also used, but tempeh has become the standard spelling in English since the 1960s.
Amnesty International has received reports of violence against lesbians in Jamaica, including rape and other forms of sexual violence. Lesbians reportedly have been attacked on the grounds of masculine physical appearance or other visible signs of sexuality. Some reports of abduction and rape come from inner-city communities, where local non-governmental organizations have expressed concerns about high incidents of violence against women.
promoter A sequence or region of DNA, usually 100–1,000 base pairs long, which regulates the expression of one or more associated genes by containing binding sites for transcription factors which recruit RNA polymerase to the sequence and initiate transcription. Promoters are typically located immediately upstream of the genes they regulate, near to and often including the transcription start site.
=== Sensors === Magnetohydrodynamic sensors are used for precise measurements of angular velocity in inertial navigation systems such as those used in aerospace engineering. Accuracy improves with sensor size. The sensor is capable of operating in harsh environments.
However, package models do not solve the error threshold problem that originally motivated the idea of the hypercycle. A few years later, Maarten Boerlijst and Paulien Hogeweg, and later Nobuto Takeuchi, studied the replicator equations with the use of partial differential equations and cellular automata models, methods that already proved to be successful in other applications. They demonstrated that spatial self-structuring of the system completely solves the problem of global extinction for large systems and, partially, the problem of parasites. The latter was also analysed by Robert May, who noticed that an emergent rotating spiral wave pattern, which was observed during computational simulations performed on cellular automata, proved to be stable and able to survive the invasion of parasites if they appear at some distance from the wave core. Unfortunately, in this case, rotation decelerates as the number of hypercycle members increases, meaning that selection tends toward decreasing the amount of information stored in the hypercycle. Moreover, there is also a problem with adding new information into the system. In order to be preserved, the new information has to appear near to the core of the spiral wave. However, this would make the system vulnerable to parasites, and, as a consequence, the hypercycle would not be stable.
Sources: en.wikipedia.org
At the start of 2014, the company out-licensed its Friedreich's ataxia program, including a library of histone deacetylase inhibitor compounds, to BioMarin Pharmaceutical for US$2,000,000 and future milestone and royalty payments. Repligen has made several acquisitions through the early 2020s, including BioFlex Solutions and Tantti Laboratory Inc. among others. As of 2024, the company's President and Chief Executive Officer is Olivier Loeillot. As of 2025 it employs approximately 2,000 employees across several sites in the United States, Europe, and Asia.
==== Frogs ==== A Ricker-complete marking system using freeze brands has been tested on tailed frogs. Previous methods of marking wild amphibians intended for recapture included hot branding, toe clipping, jaw tags, elastic waistbands and India ink scarification. These can be broadly categorized into tagging and mutilation. In scientific circles freeze branding is considered a kind of tagging: it has no permanent effect other than to identify individuals. Mutilation, on the other hand, can strongly affect an individual's life history. This may subsequently pollute scientific data gathered from studying animals that have been marked through mutilation. Toe-clipping is commonly used but it can affect the anuran's motor skills and also cause weight loss. These consequences of human interference will all affect an animal's mortality rate and hence invalidate scientific conclusions drawn from their study. Freeze branding is therefore seen as a permanent and low-impact means of tracking amphibians. Freeze branding was tested on frogs that were released into the wild after branding and later recaptured. One set of researchers used a branding iron made from a length of copper wire, cooled in a dry ice ethanol bath for 30 minutes. The brand was then applied to the anuran's skin for about ten seconds. The brand was then re-cooled for 20–30 seconds before being applied to a new frog. By using various numbers and orientations while differentiating for sex, it is possible to create a sufficient number of combinations to mark large populations of frogs.
Blood pressure: First-line agents include thiazide-type diuretics, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and calcium channel blockers. Selection depends on comorbid conditions and tolerance. Dyslipidaemia: Statins remain first-line therapy for lowering low-density lipoprotein cholesterol (LDL-C). Fibrates or omega-3 fatty acids may be added for persistent severe hypertriglyceridaemia. Glucose control: Lifestyle intervention is the foundation of therapy. When medications are required, glucose-lowering agents with demonstrated cardiovascular and renal benefits—such as glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose cotransporter-2 (SGLT2) inhibitors—are preferred for individuals with type 2 diabetes or elevated cardiovascular risk. Obesity management: Pharmacotherapies such as semaglutide and tirzepatide produce clinically significant weight loss and improvements in blood pressure, lipids, and glycaemic control. Randomized controlled trials have reported reduced major adverse cardiovascular events in adults with overweight or obesity and established cardiovascular disease.
During the 1950s and 1960s, CSL produced semisynthetic penicillin as well. Penicillin was also produced by F.H. Faulding in South Australia, Abbott Laboratories in New South Wales and Glaxo in Victoria. By the 1970s there was a worldwide glut of penicillin. Glaxo ceased production in 1975 followed by CSL in 1980.
Sources: en.wikipedia.org
Native GLP-1 is degraded within minutes by dipeptidyl peptidase-4 and neutral endopeptidases. Semaglutide carries a non-natural amino acid at position eight that blocks that cleavage, and a fatty diacid side chain that binds albumin. The result is a much longer duration of action than the native hormone.
The fatty diacid chain associates strongly with serum albumin, which keeps the peptide in circulation and shields it from rapid renal clearance. Bound peptide is released gradually, producing a sustained receptor signal. This mechanism also reduces the peak-to-trough variation seen with shorter-acting analogues.
The balance between peripheral receptor activation and signalling in the central nervous system is not fully resolved. The extent to which slowed gastric emptying accounts for reduced energy intake, compared with direct effects on appetite circuits, is debated. Long-term effects on lean mass and on tissues outside the gut and brain are still under study.
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.