This is a working overview of incretin, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-08-31 and is reviewed periodically as new material appears.
当前公开资料把 tirzepatide 归为肠促胰素类受体双重激动剂。它并非激素天然变体，而是经过序列改造的工程化肽。其分子量、等电点与疏水性等基础参数已在药典和化学数据库中收录，可作为分析检测和质量研究的参照。
Tirzepatide 是一种由 39 个氨基酸组成的合成肽，分子结构上以 GIP 序列为骨架并引入脂肪酸侧链修饰，使其能够同时与葡萄糖依赖性促胰岛素多肽（GIP）受体和胰高血糖素样肽-1（GLP-1）受体结合。这种双重激动特性使它在同类肽类药物中区别于选择性 GLP-1 受体激动剂。该分子最早由一家制药公司在 2010 年代报道，随后进入糖尿病与体重管理领域的临床研究。
Purified material is typically handled as a lyophilized powder kept at or below minus twenty degrees Celsius, shielded from light and moisture. In that state the solid remains stable for extended periods, although repeated freeze-thaw cycling can encourage aggregation. Once dissolved, aqueous solutions are less durable and are generally held cold and used within a brief window. Buffer composition, pH and ionic strength all influence degradation rates, and mildly acidic to neutral conditions are commonly examined. Actual shelf life depends on formulation, concentration and container, so stability limits are established experimentally rather than assumed.
Verification of research-grade material involves checking purity, sequence and counter-ion content against a certificate of analysis. Reported purity figures usually reflect chromatographic area percentage and do not by themselves establish biological activity. Independent laboratories may repeat mass confirmation and peptide mapping to detect substitutions or truncations. Open questions concern how residual solvents, trace metals and subtle conformational variants affect measured behavior, and how consistently different suppliers define their specifications. Documentation of analytical methods matters as much as the headline purity number when results are compared across studies.
Routine characterization relies on reversed-phase high-performance liquid chromatography, often coupled to mass spectrometry, to confirm identity and estimate purity. Peptide mapping after enzymatic digestion verifies the amino acid sequence and locates appended groups such as the fatty acid chain. Size-exclusion chromatography detects aggregates and fragments, while ion-exchange chromatography resolves charge variants. Circular dichroism and nuclear magnetic resonance supply secondary and higher-order structural information in research settings. No single technique covers every attribute, so laboratories combine orthogonal methods and compare outcomes against a reference standard where one exists.
| Property | Value | Notes |
|---|---|---|
| 分子类型 | 合成修饰肽 | 39 个氨基酸，含脂肪酸侧链 |
| 受体靶点 | GIP 与 GLP-1 受体 | 双重激动剂 |
| 分子量 | 约 4.8 kDa | 以游离肽计 |
| 外观 | 白色至类白色粉末 | 冻干形态常见 |
| 溶解性 | 可溶于水及水性缓冲液 | 溶解后宜低温保存 |
Tirzepatide is a synthetic peptide that activates both the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. This dual agonist profile distinguishes it from earlier incretin-based compounds that act on a single receptor. The molecule was engineered from the native GIP sequence and carries several non-natural residues that slow enzymatic breakdown. Researchers designed it to combine the insulinotropic effects of GIP signaling with the appetite and gastric-emptying effects associated with GLP-1 activation.
Development of tirzepatide took place under a research program that sought to test whether simultaneous engagement of two incretin receptors would produce greater metabolic effects than single-receptor agonism. Clinical trials were organized into the SURPASS series for type 2 diabetes and the SURMOUNT series for obesity and weight management. Regulatory clearance for type 2 diabetes came in 2022 in the United States, followed by approval for chronic weight management in 2023. The trial programs reported reductions in glycated hemoglobin and body weight relative to comparators, though long-term cardiovascular and durability data continue to accumulate.
The peptide backbone contains 39 amino acids and includes alpha-aminoisobutyric acid residues, which are not among the standard proteinogenic set. A C20 fatty diacid moiety is attached through a linker, allowing the compound to bind serum albumin and extend its circulation time. This albumin binding is the main reason the molecule supports once-weekly administration rather than more frequent dosing. The measured molecular mass is approximately 4,813 daltons, placing it firmly in the peptide rather than small-molecule class.
Dual agonism at the GIP and GLP-1 receptors underlies the observed pharmacology. Activation of GLP-1 receptors raises glucose-dependent insulin release, lowers glucagon secretion, slows gastric emptying and reduces appetite. GIP receptor activation contributes additional effects on adipose tissue and on energy balance, and the combined action on appetite appears larger than either pathway alone in animal models. Signalling bias and the relative contribution of each receptor arm to weight-related effects remain areas of active investigation.
Structure-activity work shows that fatty acid length, linker chemistry and the position of acylation all influence albumin affinity and receptor potency. Plasma protein binding exceeds 99 percent, which restricts distribution and slows renal clearance. Degradation proceeds largely through general proteolysis and fatty acid oxidation rather than cytochrome P450 metabolism, so exposure to common oxidative drug interactions is limited. Whether these clearance routes vary meaningfully between individuals is not fully established.
The molecule is a synthetic 39-amino-acid peptide whose backbone derives from the sequence of human glucose-dependent insulinotropic polypeptide, with several substitutions that raise metabolic stability and shift receptor preference. A C20 fatty diacid is attached through a short linker to a lysine side chain, a modification that increases binding to serum albumin. The reported monoisotopic mass is approximately 4813 Da. Near neutral pH the peptide carries a net negative charge, and the lipid tail makes the molecule markedly more hydrophobic than the unmodified parent sequence.
Solid tirzepatide is handled as a lyophilised, hygroscopic peptide powder that should be kept desiccated, protected from light, and stored frozen, typically at or below minus twenty degrees Celsius for long-term retention. Material left at ambient temperature for extended periods can take up moisture, which promotes aggregation and deamidation. Commercial liquid presentations are kept refrigerated between two and eight degrees Celsius and are not frozen. Reconstituted laboratory solutions are generally held cold and used within a short window because hydrolysis and oxidation continue slowly in solution.
Identity and purity are usually established with reversed-phase high-performance liquid chromatography for the main peak and with mass spectrometry for the observed molecular mass. Peptide mapping after enzymatic digestion confirms the primary sequence, while amino acid analysis provides a quantitative composition check. Size-exclusion chromatography and ion-exchange chromatography are used to look for aggregates and charge variants. Water content, residual solvents, and counter-ion content are measured separately, since a lyophilised powder is often reported on an as-is basis unless a correction is applied.
Research-grade material circulates through suppliers that differ widely in documentation and testing practice, so a certificate of analysis is a starting point rather than proof of quality. Independent verification typically repeats chromatographic purity and mass confirmation on the received lot, and compares results against a retained reference standard. Regulatory status varies by jurisdiction, and a substance cleared as a medicine is not interchangeable with a research chemical of the same name. Open questions include how closely non-pharmaceutical lots match approved material in impurity profile and in aggregate content.
The GIP receptor is expressed in pancreatic islets, adipose tissue, and the central nervous system, while GLP-1 receptors are found in pancreatic islets, the gastrointestinal tract, and the brain. Activation of both receptors can enhance glucose-dependent insulin secretion and reduce glucagon release. The relative contribution of each receptor to the overall pharmacological effect remains an area of ongoing investigation. Preclinical studies suggest that GIP receptor agonism may modulate appetite and energy balance, but the precise mechanisms in humans are not fully established.
In clinical research, tirzepatide has been studied in randomized controlled trials for glycemic control and body weight reduction. These trials typically measure changes in hemoglobin A1c and body weight over periods of several months. The drug is administered by subcutaneous injection, and its pharmacokinetic profile supports once-weekly dosing. Post-marketing surveillance continues to evaluate long-term outcomes and rare adverse events.
Tirzepatide is a synthetic peptide that acts as a dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. The molecule contains 39 amino acids and features a C20 fatty diacid moiety attached via a linker, which promotes albumin binding and extends its circulating half-life. Its sequence incorporates non-natural amino acids and modifications that reduce susceptibility to degradation by dipeptidyl peptidase-4. This dual receptor activity distinguishes it from selective GLP-1 receptor agonists.
==== Efficacy against Russia ==== Academic Jeremy Garlick writes that sanctions against Russia have, at least in the short term, backfired both economically and geopolitically, benefiting Russia's economy and bringing Russia and China closer together. Following the Russian invasion of Ukraine, Asian countries—primarily China and India—absorbed an increasing share of Russian oil and gas. Because Russian imports from the West declined after sanctions, Russia's trade balance rose sharply, increasing cash reserves. By June 2022, the Russian ruble had risen sharply and was among the world's best-performing currencies. In October 2025, the United States imposed sanctions against Russia's largest oil companies Rosneft and Lukoil, and threatened secondary sanctions against foreign financial institutions and companies continuing to do business with them, with particular implications for customers in China and India.
== Location == Myofibroblasts were first identified in granulation tissue during skin wound healing. Typically, these cells are found in granulation tissue, scar tissue (fibrosis) and the stroma of tumours. They also line the gastrointestinal tract, wherein they regulate the shapes of crypts and villi.
Chez Ashton is a regional fast food restaurant in Quebec that is famous for its poutine. Chez Ashton was started as a travelling snack cart by Ashton Leblond in 1969. In 1972, poutine was first offered. Leblond hooked his customers by giving free samples of his poutine. The enterprise grew in popularity until Leblond was able to open a restaurant with a dining room open year-round in 1976. The franchise has grown to include 25 restaurants in the Quebec City region.
== Alternative for specimen transport == One common alternative to dry shippers is using dry ice. This method reduces package weight and costs since there's no need for return shipping, unlike with dry shippers. However, at -80 °C (176 °F), dry ice might not provide a temperature low enough for all specimens. For instance, while cryopreserved mouse spermatozoa can handle this temperature for short periods without losing their fertilization capacity, cryopreserved mouse embryos require colder environments, such as those below -150 °C (302 °F) in dry shippers, to maintain their quality. Another method is shipping freeze-dried samples at ambient temperatures, as seen with freeze-dried mouse spermatozoa. This can be more cost-effective, but many samples, when freeze-dried, experience a notable decline in quality, limiting its applicability.
Sources: en.wikipedia.org
Scott at the University of Chicago tried aqueous pancreatic extracts and noted "a slight diminution of glycosuria", but was unable to convince his director of his work's value; it was shut down. Israel Kleiner demonstrated similar effects at Rockefeller University in 1915, but World War I interrupted his work and he did not return to it. In 1916, Nicolae Paulescu developed an aqueous pancreatic extract which, when injected into a diabetic dog, had a normalizing effect on blood sugar levels. He had to interrupt his experiments because of World War I, and in 1921 he wrote four papers about his work carried out in Bucharest and his tests on a diabetic dog. Later that year, he published "Research on the Role of the Pancreas in Food Assimilation". The name "insulin" was coined by Edward Albert Sharpey-Schafer in 1916 for a hypothetical molecule produced by pancreatic islets of Langerhans (Latin insula for islet or island) that controls glucose metabolism. Unbeknown to Sharpey-Schafer, Jean de Meyer had introduced the very similar word "insuline" in 1909 for the same molecule.
=== Names === Diamorphine is the international nonproprietary name and the British Approved Name. Other synonyms for heroin include: diacetylmorphine, and morphine diacetate. Heroin is also known by many street names including Big H, Black Tar, Chiva, Hell Dust, Horse, Negra, Smack, Thunder, dope, H, smack, junk, skag, brown, and unga among others. Whoonga (or wonga), nyaope and sugars are South African street names for heroin.
== Publications == Ondetti M A, Sabo E F. Angiotensin-converting enzyme inhibitors from the venom of Bothrops jararaca. Isolation, elucidation of structure, and synthesis, Biochemistry 1971; 10 (22): 4033–4039. Ondetti M A, Rubin B, Cushman D W. Design of specific inhibitors of angiotensin-converting enzyme: new class of orally active antihypertensive agents, Science 1977; 196 (4288): 441–444.
Sources: en.wikipedia.org
== Discography == Studio albums (A Lament for...) The Addicts (2007) Leaving Paris (2010) Hope /// Dope /// Rope (2012) This Is Not Supposed To Be Positive (2015) Banlieue Triste (2018) A Loner (2022) Saddiction (2025) EPs Bus de Nuit (2019) Split albums Hangman's Chair / Eibon (2007) Hangman's Chair / Drawers (2012) Hangman's Chair / Acid Deathtrip (2014) Hangman's Chair / Greenmachine (2017)
Chasing the Scream: The First and Last Days of the War on Drugs was published in the UK on January 15th, 2015, followed by the US on January 20th the same month. Chasing the Scream critiques the global prohibition of illicit narcotics. Hari argued that most addictions are functional responses to experiences and a lack of healthy supportive relationships, rather than a simple biological need for a particular substance. Due to the previous scandals, Hari put the audio of some interviews conducted for Chasing the Scream online. Writer Jeremy Duns criticised instances where quotes were inaccurately transcribed or misrepresented, stating that out of a sample of dozens of clips, "in almost all cases, words in quotes had been changed or omitted without being noted, often for no apparent purpose, but in several cases to subtly change the narrative." In a review for New Matilda, Michael Brull expressed reservations about Hari's citational practices and highlighted contradictions between the narrative in Chasing the Scream and a 2009 article by Hari. For newer UK editions, the subtitle has been changed: Chasing the Scream: The Search for the Truth About Addiction.
== History == In 1968, a reduced T4 half-life in athletes was discovered. This was the first awareness of thyroid hormone concentration alterations that were not a result of thyroid gland or pituitary dysfunction. In 1971, they also found a transient increase in T4 during bicycle training. In 1973, Rothenbuchner et al. discovered that starvation is correlated with reduced T3 concentration. Following this, a similar phenotype was noted in patients with critical illness, tumors, and uremia. The alternative phenotype of type-2 thyroid allostasis was first predicted in 1968, when John W. Mason expected the concentrations of thyroid hormones to rise in situations of psychosocial stress. Mason's postulate was later confirmed by numerous studies.
CPA3 (also known as mast-cell CPA) is involved in the digestion of proteins by mast cells. CPA4 (previously known as CPA-3, but renumbered when mast-cell CPA was designated CPA-3) may be involved in tumor progression, but this enzyme has not been well studied. CPA5 has not been well studied. CPA6 is expressed in many tissues during mouse development, and in adult shows a more limited distribution in brain and several other tissues. CPA6 is present in the extracellular matrix where it is enzymatically active. A human mutation of CPA-6 has been linked to Duane's syndrome (abnormal eye movement). Recently, mutations in CPA6 were found to be linked to epilepsy. CPA6 is also one of several enzymes which degrade enkephalins.
Sources: en.wikipedia.org
它属于合成修饰肽，同时激动 GIP 与 GLP-1 两种肠促胰素受体。这类分子通常被称为双重肠促胰素受体激动剂，与选择性 GLP-1 激动剂在靶点范围上不同。
分子上的脂肪酸侧链使其与血浆白蛋白结合增强，显著延长循环半衰期。半衰期延长后，稳定血药浓度可在较长的给药间隔内维持，因此常见用法为每周一次。
同时激活两条肠促胰素通路可能在胰岛素分泌、胃排空和食欲调节上产生叠加效应。与单靶点相比，临床研究中观察到的血糖与体重变化幅度通常更明显，但各通路的具体贡献比例尚无定论。
Liquid chromatography combined with mass spectrometry is the most common approach. Digestion followed by peptide mapping verifies the sequence and modification sites. Results are judged against a reference standard or a theoretically calculated mass.