If you have been reading about incretin 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 2026-07-03. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Clinical studies of semaglutide generally measure glycated hemoglobin, fasting plasma glucose, body weight, and composite cardiovascular endpoints. The SUSTAIN program enrolled adults with type 2 diabetes, while the STEP program focused on obesity without diabetes. Administration follows a stepwise escalation schedule designed to limit gastrointestinal effects during the first weeks. Reported outcomes include mean percentage weight change, the proportion of participants reaching defined weight-loss thresholds, and rates of nausea, vomiting, and diarrhea. Long-term data on durability after treatment stops are still limited and remain a topic of ongoing research.
Semaglutide is a synthetic peptide analog of human glucagon-like peptide-1, developed by Novo Nordisk and first approved in 2017 for type 2 diabetes. It belongs to the incretin mimetic class, a group of agents that reproduce the glucose-dependent actions of endogenous GLP-1. The molecule was engineered to resist degradation by dipeptidyl peptidase-4 and to bind serum albumin, extending its half-life from minutes to roughly one week. Approval for chronic weight management followed in 2021, based on large cardiovascular and obesity outcome trials.
| Property | Value | Notes |
|---|---|---|
| Molecular class | 31-amino-acid peptide | Modified glucagon-like peptide-1 analogue |
| Molecular mass | approximately 4114 Da | Calculated for the free peptide backbone |
| Appearance | white to off-white powder | Typical of purified lyophilised peptide batches |
| Solubility class | freely soluble in water | Aqueous solubility improves at slightly alkaline pH |
| Typical storage | -20 degrees Celsius, dry, dark | Protect from repeated freeze-thaw cycles |
These developments led to advances in the field of evolutionary developmental biology towards understanding how the various body plans of the animal phyla have evolved and how they are related to one another. The Human Genome Project—the largest, most costly single biological study ever undertaken—began in 1988 under the leadership of James D. Watson, after preliminary work with genetically simpler model organisms such as E. coli, S. cerevisiae and C. elegans. Shotgun sequencing and gene discovery methods pioneered by Craig Venter—and fueled by the financial promise of gene patents with Celera Genomics— led to a public–private sequencing competition that ended in compromise with the first draft of the human DNA sequence announced in 2000.
== History == The backdoor pathway to DHT biosynthesis was discovered in early 2000s in the marsupials and later confirmed in humans. That is why the backdoor pathway of DHT biosynthesis from 17OHP can be called a marsupial pathway. This pathway is also present in other mammals, such as rats, and are studied in the other mammals as a way to better understand these pathways in humans. Marsupials, and in particular, tammar wallabies (Notamacropus eugenii) are especially useful for studying the processes of sexual differentiation and development in the context of androgen biosynthesis, because sexual differentiation in these species occurs only after birth, with testes beginning to form two days after birth and ovaries only on the eighth day after birth. This feature of post-natal early sexual differentiation allows scholars to study the influence of hormones on the body from the very beginning of the process of sexual differentiation, as well as the pathways of biosynthesis of these hormones. Tammar wallabies are particularly interesting due to the fact that all these hormones, pathways, and the ways in which hormones affect body features and growth of different organs can be studied when the organism is already born, unlike in other mammals such as rats, where sexual differentiation in a fetus occurs inside the placenta before birth.
A blood smear, peripheral blood smear or blood film is a thin layer of blood smeared on a glass microscope slide and then stained in such a way as to allow the various blood cells to be examined microscopically . Blood smears are examined in the investigation of hematological (blood) disorders and are routinely employed to look for blood parasites, such as those of malaria and filariasis.
Erinacines are natural substances isolated from the mycelium of Hericium erinaceus (lion's mane mushroom). They belong to the group of cyathin diterpenoids (erinacines A–K, P, Q, S, U) and are subjects of pharmacological research, which largely focuses on the benefits of erinacine on the brain. All erinacines are able to readily cross the blood–brain barrier in vivo, which largely influences the bioavailability of the compounds in the brain.
=== Other drugs === Nefopam—a monoamine reuptake inhibitor, and calcium and sodium channel modulator—is also approved for the treatment of moderate to severe pain in some countries. Flupirtine is a centrally acting K+ channel opener with weak NMDA antagonist properties. It was used in Europe for moderate to strong pain, as well as its migraine-treating and muscle-relaxant properties. It has no significant anticholinergic properties, and is believed to be devoid of any activity on dopamine, serotonin, or histamine receptors. It is not addictive, and tolerance usually does not develop. However, tolerance may develop in some cases. Ziconotide, a blocker of potent N-type voltage-gated calcium channels, is administered intrathecally for the relief of severe, usually cancer-related pain.
Sources: en.wikipedia.org
Kynureninase or L-Kynurenine hydrolase (KYNU) (EC 3.7.1.3) is a pyridoxal-phosphate dependent enzyme that catalyses the cleavage of kynurenine into anthranilic acid. It can also act on 3-hydroxykynurenine (to produce 3-hydroxyanthranilate) and some other (3-arylcarbonyl)-alanines. Humans express one kynureninase enzyme that is encoded by the KYNU gene located on chromosome 2. KYNU is part of the pathway for the catabolism of tryptophan and the biosynthesis of nicotinamide adenine dinucleotide (NAD) cofactors from tryptophan (Trp). This reaction produces anthranilic acid and L-alanine:
Conscious proprioception is communicated by the dorsal column-medial lemniscus pathway to the cerebrum. Nonconscious proprioception is communicated primarily via the dorsal spinocerebellar tract and ventral spinocerebellar tract, to the cerebellum. A nonconscious reaction is seen in the human proprioceptive reflex, or righting reflex—in the event that the body tilts in any direction, the person will cock their head back to level the eyes against the horizon. This is seen even in infants as soon as they gain control of their neck muscles. This control comes from the cerebellum, the part of the brain affecting balance.
===== Gravimetric method ===== The increased mass of the MOF due to the stored hydrogen is directly calculated by a sensitive microbalance. Due to buoyancy, the detected mass of adsorbed hydrogen decreases again when a sufficiently high pressure is applied to the system because the density of the surrounding gaseous hydrogen becomes more and more important at higher pressures. Thus, this "weight loss" has to be corrected using the volume of the MOF's frame and the density of hydrogen.
The Crick, Brenner, Barnett and Watts-Tobin experiment first demonstrated that codons consist of three DNA bases. Marshall Nirenberg and J. Heinrich Matthaei were the first to reveal the nature of a codon in 1961. They used a cell-free system to translate a poly-uracil RNA sequence (i.e., UUUUU...) and discovered that the polypeptide that they had synthesized consisted of only the amino acid phenylalanine. They thereby deduced that the codon UUU specified the amino acid phenylalanine. This was followed by experiments in Severo Ochoa's laboratory that demonstrated that the poly-adenine RNA sequence (AAAAA...) coded for the polypeptide poly-lysine and that the poly-cytosine RNA sequence (CCCCC...) coded for the polypeptide poly-proline. Therefore, the codon AAA specified the amino acid lysine, and the codon CCC specified the amino acid proline. Using various copolymers most of the remaining codons were then determined. Subsequent work by Har Gobind Khorana identified the rest of the genetic code. Shortly thereafter, Robert W. Holley determined the structure of transfer RNA (tRNA), the adapter molecule that facilitates the process of translating RNA into protein. This work was based upon Ochoa's earlier studies, yielding the latter the Nobel Prize in Physiology or Medicine in 1959 for work on the enzymology of RNA synthesis. Extending this work, Nirenberg and Philip Leder revealed the code's triplet nature and deciphered its codons.
=== Drift tube ion mobility spectrometry === Drift tube ion mobility spectrometry (DTIMS) measures how long a given ion takes to traverse a given length in a uniform electric field through a given atmosphere. In specified intervals, a sample of the ions is let into the drift region; the gating mechanism is based on a charged electrode working in a similar way as the control grid in triodes works for electrons. For precise control of the ion pulse width admitted to the drift tube, more complex gating systems such as a Bradbury–Nielsen or a field switching shutter are employed. Once in the drift tube, ions are subjected to a homogeneous electric field ranging from a few volts per centimetre up to many hundreds of volts per centimetre. This electric field then drives the ions through the drift tube where they interact with the neutral drift molecules contained within the system and separate based on the ion mobility, arriving at the detector for measurement. Ions are recorded at the detector in order from the fastest to the slowest, generating a response signal characteristic for the chemical composition of the measured sample. The ion mobility K can then be experimentally determined from the drift time tD of an ion traversing within a homogeneous electric field the potential difference U in the drift length L.
Sources: en.wikipedia.org
Respondents in the 2021 Canadian census self-reported over 450 "ethnic or cultural origins". The major panethnic groups chosen were: European (52.5%), North American (22.9%), Asian (19.3%), North American Indigenous (6.1%), African (3.8%), Latin, Central and South American (2.5%), Caribbean (2.1%), Oceanian (0.3%), and other (6%). Over 60 percent of Canadians reported a single origin, and 36 percent reported having multiple ethnic origins, thus the overall total is greater than 100 percent.
Archaeological evidence indicates that the use of medicinal plants dates back to the Paleolithic age, approximately 60,000 years ago. Written evidence of herbal remedies dates back over 5,000 years to the Sumerians, who compiled lists of plants. Some ancient cultures wrote about plants and their medical uses in books called herbals. In ancient Egypt, herbs were mentioned in Egyptian medical papyri, depicted in tomb illustrations, or on rare occasions found in medical jars containing trace amounts of herbs. In ancient Egypt, the Ebers papyrus dates from about 1550 BCE, and covers more than 700 compounds, mainly of plant origin. The earliest known Greek herbals came from Theophrastus of Eresos who, in the 4th century BCE, wrote in Greek Historia Plantarum, from Diocles of Carystus who wrote during the 3rd century BCE, and from Krateuas who wrote in the 1st century BCE. Only a few fragments of these works have survived intact, but from what remains, scholars have noted an overlap with the Egyptian herbals. Seeds likely used for herbalism were found in archaeological sites of Bronze Age China dating from the Shang dynasty (c. 1600 – c. 1046 BCE). Over a hundred of the 224 compounds mentioned in the Huangdi Neijing, an early Chinese medical text, are herbs. Herbs were also commonly used in the traditional medicine of ancient India, where the principal treatment for diseases was diet. De Materia Medica, originally written in Greek by Pedanius Dioscorides (c. 40 – c.
The three substrates of this enzyme are saccharopine, oxidised nicotinamide adenine dinucleotide phosphate (NADP+), and water. Its products are L-lysine, α-ketoglutaric acid, reduced NADPH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is N6-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming). Other names in common use include lysine-2-oxoglutarate reductase, lysine-ketoglutarate reductase, L-lysine-alpha-ketoglutarate reductase, lysine:alpha-ketoglutarate:TPNH oxidoreductase, (epsilon-N-[gultaryl-2]-L-lysine forming), saccharopine (nicotinamide adenine dinucleotide phosphate,, lysine-forming) dehydrogenase, 6-N-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase, and (L-lysine-forming). This enzyme participates in lysine biosynthesis and lysine degradation.
Many thousands of perceived dissidents were arbitrarily tried and large numbers were executed.[u] The People's Republic was led by discredited Soviet operatives such as Bolesław Bierut, Jakub Berman and Konstantin Rokossovsky. The independent Catholic Church in Poland was subjected to property confiscations and other curtailments from 1949, and in 1950 was pressured into signing an accord with the government. In 1953 and later, despite a partial thaw after the death of Stalin that year, the persecution of the Church intensified and its head, Cardinal Stefan Wyszyński, was detained. A key event in the persecution of the Polish Church was the Stalinist show trial of the Kraków Curia in January 1953. In the Warsaw Pact, formed in 1955, the Polish Army was the second largest, after the Soviet Army.
Sources: en.wikipedia.org
It is a glucagon-like peptide-1 receptor agonist, often grouped with the incretin mimetics. Its backbone is modified from the human hormone to resist enzymatic degradation and to bind albumin. These two features distinguish it from the native peptide.
No. It shares high sequence identity but carries non-natural modifications that alter its stability and clearance. The naturally occurring hormone is broken down within minutes, while the synthetic analogue circulates far longer.
Attachment to serum albumin reduces renal filtration of the peptide and shields it from enzymatic breakdown. The consequence is a much longer interval between administrations than unmodified peptides allow. The precise contribution of binding affinity to overall duration is still being quantified.
It is given either as a once-weekly subcutaneous injection or as an oral tablet taken once daily. The two forms use different absorption strategies, so they are not interchangeable on a milligram-for-milligram basis.