Everything below concerns deamidation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
The compound first appeared in the scientific literature as an investigational agent for type 2 diabetes. Clinical development proceeded through phase 1, phase 2, and phase 3 programs that measured glycemic control as a primary endpoint while recording body weight as a secondary outcome. Regulatory approval in the United States followed in 2022 for glycemic control, and a separate indication for chronic weight management was added later. Subsequent trials have examined cardiovascular outcomes in adults with elevated cardiovascular risk. Debates continue over how much of the observed effect derives from each receptor arm.
Structural work on the molecule centers on a C20 fatty diacid moiety attached through a linker to the peptide backbone. This side chain promotes reversible binding to serum albumin, which slows renal clearance and supports a prolonged action profile. The peptide backbone incorporates aminoisobutyric acid substitutions that limit recognition by digestive enzymes. Together these modifications produce a molecule that is stable enough for subcutaneous delivery but still dependent on careful manufacturing control. Analytical characterization of the active pharmaceutical ingredient typically follows the conventions used for other synthetic peptides.
Tirzepatide is a synthetic peptide composed of 39 amino acids. It acts as a dual agonist at two incretin receptors, the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. The molecule was designed by modifying the native sequence of glucose-dependent insulinotropic polypeptide to improve metabolic stability and extend its circulation time. Its structure includes several non-natural amino acid residues and a fatty acid side chain. These features distinguish it from earlier single-receptor incretin analogs studied in the same period.
质量控制环节关注外观、含量、纯度、有关物质、水分与微生物限度等项目。检测结果需要有对照品和系统适用性数据支持，单次测定不足以判定批次的稳定性。实验室之间方法转移时，色谱柱品牌与梯度差异常导致保留时间漂移，因此方法验证十分必要。
固体状态的 tirzepatide 通常以冻干粉形式保存，推荐在低温、避光、干燥条件下存放，常见区间为 2 至 8 摄氏度，长期保存可考虑更低温度并避免反复冻融。冻融循环会导致肽链聚集或析出，从而影响后续定量结果。容器密封性与湿度控制同样是稳定性研究中反复强调的因素。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Dual incretin receptor agonist |
| Amino acid count | 39 residues | Includes non-natural residues |
| Approximate mass | 4.8 kDa | Reported values vary slightly by source |
| Fatty acid component | C20 diacid | Supports albumin binding |
| First US approval | 2022 | Glycemic indication, weight management followed |
脂肪酸侧链的存在使该肽与血浆白蛋白结合能力增强，从而延长循环半衰期，支持每周一次给药的用药间隔。白蛋白结合同时改变组织分布特征，减慢肾脏清除速度。该设计思路在多种长效肽类药物中被反复采用，属于既定的药代动力学策略。
该化合物的名称与结构由国际非专利名称体系统一维持，不同文献中出现的同义写法主要在拼写顺序或盐形式描述上不同。研究者通常通过受体结合实验、细胞内环磷酸腺苷积累测定以及动物模型来确认其双激动活性。相当一部分分子层面的细节——例如两条受体通路之间的信号交叉作用——尚处于开放问题状态。
Routine characterization of the peptide relies on reversed-phase high-performance liquid chromatography for purity assessment, usually with ultraviolet detection near 214 nanometers. Intact mass measurement by liquid chromatography coupled to mass spectrometry confirms molecular identity against a theoretical value. Sequence-level confirmation uses enzymatic digestion followed by tandem mass spectrometry, an approach known as peptide mapping. Amino acid analysis gives an independent check on composition. Circular dichroism spectra are used to estimate helical content in aqueous buffer.
Stability depends strongly on physical form. The dry powder is generally regarded as stable for extended periods when held at or below minus twenty degrees Celsius in a sealed, desiccated container. In solution, degradation pathways include deamidation of asparagine and glutamine residues, oxidation of methionine, and aggregation. Reaction rates for these pathways rise with temperature. Repeated freezing and thawing of solutions promotes aggregation, and light exposure can accelerate some oxidative changes. Buffer composition and pH influence which pathway dominates at a given temperature.
At the receptor level, tirzepatide activates both the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. Both belong to the class B family of G protein-coupled receptors and signal largely through cyclic AMP accumulation. The compound binds the two receptors with differing affinity, and the pattern of signaling at each site is described in the literature as biased rather than simply proportional to occupancy. Tissues carrying these receptors include pancreatic islets, adipose tissue, the central nervous system, and the gastrointestinal tract. The relative weight of each receptor population in producing metabolic effects continues to be studied.
Published work supports the view that engaging two incretin receptors produces changes in glucose handling and body weight larger than those seen with single-receptor activation. Why that difference arises is not fully settled. Open questions include how much of the observed weight effect depends on central versus peripheral signaling, and whether the two receptors form interacting complexes. Most reported findings come from controlled trials and animal models, and translation between species is imperfect. Further research is expected to refine these points over time.
Tirzepatide is a synthetic peptide built from 39 amino acid residues. Its sequence is related to human glucose-dependent insulinotropic polypeptide, with modifications that include a C-terminal extension and a C20 fatty diacid joined through a linker. Those changes raise the molecule's affinity for serum albumin, which slows renal filtration and lengthens the time it stays in circulation. The free base has an average molecular mass near 4813.5 daltons. The compound is made by solid-phase peptide synthesis followed by chromatographic purification.
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.
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.
van Heyningen, professor emeritus, University of Oxford, UK, and John R. Seal, former scientific director, National Institute of Allergy and Infectious Diseases, Bethesda, note that De's paper "deserves to go down as a classic in the history of cholera, and, indeed, as later developments have shown, in the history of cellular physiology and biochemistry." Thanks to De's discovery of the cholera enterotoxin, research has been redirected to find a vaccine that will spark the immune system to fight the enterotoxin specifically, rather than the bacteria. De and colleagues also published highly cited pioneering studies on V. cholerae action on the intestinal membrane.,, The 1953 paper “An experimental study of the mechanism of action of Vibrio cholerae on the intestinal mucous membrane” is De’s most-cited paper, cited 340 times until August 1986. It was especially influential on research fronts on "E. coli and Vibrio cholerae enterotoxin: detection, characterization, and role of adherence" and "Characterization of cholera enterotoxin and other enterotoxins". John Craig of State University of New York Health Science Center at Brooklyn described De’s work as truly creative and novel, having “forever altered our concepts surrounding the pathogenesis of secretory diarrhoea.” These findings resulted from work he conducted at the Nilratan Sircar Medical College, Calcutta Medical College, and Bose Institute in Kolkata. His research used relatively simple and inexpensive methods. In the words of Nobel Laureate Prof.
=== Reverse osmosis and desalination === In reverse osmosis (RO) and desalination plants, antiscalants are vital for preventing scale formation on membrane surfaces. Scaling can severely impair the efficiency of these processes and lead to increased maintenance costs. Antiscalants help maintain optimal performance and prolong the lifespan of membranes. Scales form in the RO or desalination plants when the ionic product of sparingly dissolved salts in the concentrated flow equals or exceeds their solubility product. The extent and degree of scaling phenomena are determined not only by the supersaturation conditions that occurred, but also by the precipitation kinetics.
=== 10 April === Three people, including a 14-year-old child, were killed in a Russian airstrike in Lyptsi, Kharkiv Oblast. Six people, including a 10-year-old child, were killed in a Russian airstrike in Odesa. In Russia, the governor of Kursk Oblast claimed that three people, including two children were killed in a Ukrainian drone strike on a car in Korenevsky District. The Ukrainian military claimed that a Russian Ka-27 helicopter was destroyed in disputed circumstances over Chornomorske, Crimea. On the same day, the Russian Defence Ministry said that an Mi-24 helicopter crashed due to possible equipment failure off the Crimean coast. The SBU arrested a former city councilor of Bakhmut on suspicion of collaboration with Russia. The US Department of Defense sold Ukraine $138 million in spare parts to maintain and upgrade its HAWK missile systems. Germany announced a new aid package to Ukraine that included 6,000 rounds of 155 mm shells, a mine clearing tank, small arms and some one million bullets.
An alternative approach to the identification and quantification of patient samples is through the use of mass spectrometry. This approach offers excellent precision and sensitivity in the identification, characterization and quantification of metabolites in multiple patient sample types, such as blood and urine. The mass spectrometry (MS) approach is typically coupled to gas chromatography (GC), in GC-MS or liquid chromatography (LC), in LC-MS, which aid in initially separating out the metabolite components within complex sample mixtures, and can allow for the isolation of particular metabolite subsets for analysis. GC-MS can provide relatively precise quantification of metabolites, as well as chemical structural information that can be compared to pre-existing chemical libraries. GC-MS can be conducted in a relatively high-throughput manner (greater than 100 samples per day) with greater detection sensitivity than NMR analysis. A limitation of GC-MS for this application, however, is that processed metabolite components must be readily volatilized for sample processing. LC-MS initially separates out the components of a sample mixture based on properties such as hydrophobicity, before processing them for identification and quantification by mass spectrometry (MS). Overall, LC-MS is an extremely flexible method for processing most compound types in a somewhat high-throughput manner (20-100 samples a day), also with greater sensitivity than NMR analysis. For both GC-MS and LC-MS there are limitations in the reproducibility of metabolite quantification.
=== Non-medical use === Combining a muscle relaxant like carisoprodol with opioids and benzodiazepines is known as "The Holy Trinity" as it has been reported to increase the power of the "high". Recreational users of carisoprodol usually seek its potentially heavy sedating, relaxant, and anxiolytic effects. Because of its potentiating effects on narcotics, it is often used in conjunction with opioids. Carisoprodol is not tested for on standard drug testing screens, although tests for it do exist. On 26 March 2010 the DEA issued a Notice of Hearing on a proposal for placing carisoprodol in schedule IV of the Controlled Substances Act, later confirming its classification under schedule IV. Carisoprodol is sometimes mixed with date rape drugs.
Sources: en.wikipedia.org
Actinobacteria are also halophilic psyschrophiles that have been found in brine pockets, known for their ability to produce a wide range of secondary metabolites, including antibiotics and other bioactive compounds. Actinobacteria are often found in association with other microorganisms, where they may play a role in protecting their host from pathogens or other threats. Lastly, bacteroidetes are found to be abundant in brine pockets, as they can degrade complex organic matter, including carbohydrates and proteins, such as algae-derived ocean polysaccharides. Compared to other bacteria, bacteroidetes species have been shown to contain more genes associated with polysaccharide degradation, allowing them to play a major contributing role in brine pocket carbon- and nutrient-cycling.
Courtaulds purchased the patents for this process in 1904, leading to significant growth of viscose fiber production. By 1931, expiration of patents for the viscose process led to its adoption worldwide. Global production of regenerated cellulose fiber peaked in 1973 at 3,856,000 tons. Regenerated cellulose can be used to manufacture a wide variety of products. While the first application of regenerated cellulose was as a clothing textile, this class of materials is also used in the production of disposable medical devices as well as fabrication of artificial membranes.
=== Biosynthesis === Ricin is synthesized in the endosperm of castor oil plant seeds. The ricin precursor protein is 576 amino acid residues in length and contains a signal peptide (residues 1–35), the ricin A chain (36–302), a linker peptide (303–314), and the ricin B chain (315–576). The N-terminal signal sequence delivers the prepropolypeptide to the endoplasmic reticulum (ER) and then the signal peptide is cleaved off. Within the lumen of the ER the propolypeptide is glycosylated and a protein disulfide isomerase catalyzes disulfide bond formation between cysteines 294 and 318. The propolypeptide is further glycosylated within the Golgi apparatus and transported to protein storage bodies. The propolypeptide is cleaved within protein bodies by an endopeptidase to produce the mature ricin protein that is composed of a 267 residue A chain and a 262 residue B chain that are covalently linked by a single disulfide bond.
== History == Perhaps the most famous person who exemplified the appearance of untreated congenital growth hormone deficiency was Charles Sherwood Stratton (1838–1883), who was exhibited by P. T. Barnum as General Tom Thumb, and married Lavinia Warren. Pictures of the couple show the typical adult features of untreated severe growth hormone deficiency. Despite the severe shortness, limbs and trunks are proportional. By the middle of the twentieth century, endocrinologists understood the clinical features of growth hormone deficiency. GH is a protein hormone, like insulin, which had been purified from pig and cow pancreases for treatment of type 1 diabetes since the 1920s. However, pig and cow GH did not work at all in humans, due to greater species-to-species variation of molecular structure (i.e., insulin is considered more "evolutionarily conserved" than GH).
Sources: en.wikipedia.org
In Season 9, Roseanne and Jackie win a state lottery in excess of $108 million. At the end of the season, it is revealed that they never won the lottery and most of what previously happened on the show is actually from a fictional book Roseanne wrote. Her account of Dan having an affair was false and he actually suffered a fatal heart attack at the end of Season 8. Roseanne explains that his death was as if he had been unfaithful and left her. However, in Season 10, set twenty years later, the events of Season 9 are ret-conned out of existence. By this time, Roseanne is still married to Dan and is now a grandmother of three and posthumously of four. In 2018, Roseanne Barr was fired from the show after she wrote a racist tweet describing Valerie Jarrett, a black woman and one of President Barack Obama's senior advisers, as the offspring of the "Muslim Brotherhood & Planet of the Apes." In the spin-off The Conners, Roseanne has died of an accidental opioid overdose. The series, which ran for seven seasons, concluded with Dan suing the company which prescribed the opioid pills for Roseanne. In June 2010, Entertainment Weekly named Roseanne one of the 100 Greatest Characters of the Last 20 Years. In 2009, she was listed in the Top 5 Classic TV Moms by Film.com. In May 2012, she was one of the 12 moms chosen by users of iVillage on their list of "Mommy Dearest: The TV Moms You Love". AOL named her the 11th Most Memorable Female TV Character.
=== Availability === Cyclofenil remains available today only in Brazil, Italy, and Japan. In the past, it has also been available in France, Germany, Mexico, Sweden, Switzerland, Turkey, and the United Kingdom.
CGRP antagonists can be used for both acute migraine treatment as well as prophylactically. CGRP is a neuropeptide which is thought to induce migraines via vasodilation of cranial arteries. CGRP can also release inflammatory agents and cause nervous system sensitization. It is theorized that by antagonizing the CGRP receptor of the trigeminal ganglia, lowered CGRP is released and less migraine occurs. Erenumab is a highly selective human monoclonal antibody which is a promising new development in migraine treatment. It has low risk of hepatoxicity like gepants can have, due to being mostly eliminated via proteolysis. There have been some studies suggesting the benefit of using melatonin for prophylaxis of migraine, however, there is a lack of strength of evidence due to a low number of studies as well as conflicting results. Melatonin has a good safety profile but there have been rare instances of serious side effects. More studies are needed in order to suggest the therapeutic use of melatonin for prophylaxis of migraine.
Sources: en.wikipedia.org
It activates both the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. This dual activity separates it from agents that act on only one of the two receptors. The relative contribution of each receptor to clinical effects remains an open area of study.
United States approval for type 2 diabetes was granted in 2022, and a chronic weight management indication was added later. Approval timelines differ across other jurisdictions. Earlier human data came from phase 1 and phase 2 trials published before those decisions.
Native hormones are short-lived peptides that enzymes degrade within minutes. Tirzepatide carries non-natural residues and a fatty acid chain that resist this breakdown and extend circulation time. The result is a longer interval between administrations than the natural hormones could support.
建议在低温、避光、干燥环境中密封保存，常见条件为 2 至 8 摄氏度，长期存放可置于更低温度。应避免反复冻融，并尽量减少容器开启次数。