A practical reference on fatty diacid: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-12-17. Anything still debated is marked as such rather than presented as settled.
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。
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。
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.
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.
| 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 |
Clinical research programs have evaluated tirzepatide in adults with type 2 diabetes and in adults with obesity or excess weight. Trials generally reported reductions in glycated hemoglobin and body weight across treatment periods of several months. Since these studies enrolled defined populations under controlled conditions, the findings describe group averages rather than individual outcomes. Open questions include the durability of effects after treatment stops, variation among subgroups, and the long-term consequences of sustained dual receptor stimulation. Published trial summaries should be consulted for exact measurements rather than secondary accounts.
Tirzepatide is a synthetic peptide built from 39 amino acid residues. Its backbone derives from the native glucose-dependent insulinotropic polypeptide sequence, altered at several positions to resist enzymatic cleavage. A fatty diacid group attached through a linker extends plasma residence time by promoting reversible binding to serum albumin. The molecule carries a net negative charge near physiological pH and has a reported molecular weight close to 4813 daltons. These features separate it from shorter incretin analogs and account for its prolonged dosing interval.
Pharmacologically, tirzepatide activates two distinct G protein-coupled receptors: the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. Binding at each target triggers cyclic AMP accumulation and downstream signaling in pancreatic beta cells, adipose tissue and the central nervous system. Because the two pathways overlap only partially, the combined effect on insulin secretion, glucagon suppression and appetite signaling differs from that of selective single-receptor compounds. Affinity is not equal across the two targets, and the clinical meaning of that imbalance remains an area of active study.
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.
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.
After subcutaneous injection, absorption is gradual, and peak plasma levels are generally reached within one to three days. Albumin binding extends the apparent half-life to roughly five days, which supports a weekly administration schedule. Metabolism proceeds mainly through proteolytic cleavage of the peptide backbone and beta-oxidation of the fatty acid chain, rather than through cytochrome P450 pathways. Eliminated fragments are largely recycled through general protein turnover, and excretion of intact drug in urine is minimal. These properties distinguish the molecule from short-acting incretin mimetics.
Tirzepatide is a synthetic peptide of 39 amino acids engineered from the native glucose-dependent insulinotropic polypeptide sequence. Its structure incorporates several non-natural residues and a C-terminal segment derived from glucagon-like peptide-1, together with a C20 fatty diacid moiety attached through a linker. The lipophilic side chain promotes binding to serum albumin, which slows renal clearance after administration. The compound is classified as a dual incretin receptor agonist and is supplied as a lyophilized powder for reconstitution or as a preformulated solution, depending on the presentation.
The peptide shares degradation routes common to modified peptides: deamidation of asparagine and glutamine residues, oxidation of methionine, and backbone hydrolysis under extreme pH. Lyophilized material is generally more stable than a solution, and residual water content directly affects the rate of hydrolysis. In liquid form, aggregation and visible particles can appear after agitation or repeated freeze-thaw cycles. Stability studies therefore track monomer content, aggregate content, and potency over months under defined temperature and humidity.
Cold-chain handling is standard for formulated product, with dry powder stored frozen and ready-to-use solutions refrigerated. Light exposure is minimized because photodegradation of certain amino acid side chains is possible. Shipping and temperature-excursion studies are used to establish whether short deviations affect quality attributes. Documentation supplied with research material usually includes a certificate of analysis listing purity, identity confirmation, and water or residual solvent content. Users are expected to confirm that material meets the stated specification before use.
H-DNA motifs have been shown to stimulate homologous recombination with different mechanisms. Initial implications for the role of H-DNA in recombination came in the early 1990s when observing RecA, a bacterial DNA recombination protein composed of triple-helix DNA. RecA exhibits enzymatic activity essential for recombination. Homologous recombination involving H-DNA motifs have also been found in eukaryotes. RadA, a homologous protein to RecA, has been shown to have the same enzymatic activity in recombination as RecA. The protein has the ability to promote and exchange homologous strands through parallel triple stranded helices. The single stranded DNA (ssDNA) and complementary double stranded DNA (dsDNA) will form a D-loop structure. Another possible mechanism for RecA involves the ssDNA from two separate H-DNA structures to form Watson-Crick base pairs. The new structure is known as a Holliday junction, an intermediate in homologous recombination. H-DNA is also found in other forms of recombination. In mammalian cells, H-DNA-sequences displayed a high frequency of recombination. For example, a study conducted on myeloma cell line of mice found H-DNA structures in Cγ2a and Cγ2b, which participate in sister chromatid exchange.
Schober's test tests the flexion of the lower back. Multiple joint inspection Musculoskeletal Examination Screening Musculoskeletal Exam (SMSE) - a rapid assessment of structure and function General Musculoskeletal Exam (GMSE) - a comprehensive assessment of joint inflammation Regional Musculoskeletal Exam (RMSE) - focused assessments of structure, function and inflammation combined with special testing
=== Primary treatment === Primary treatment aims to remove ions, dissolved gasses, and organic contaminants from pre-treated water. In the 21st century, multiple-pass reverse osmosis is often the primary method used during this step to remove dissolved ions and dissolved organic solids. As a membrane-filtration method it also removes suspended solids as well. Reverse osmosis is often used in this step to remove both dissolved ions and dissolved organic material. Dissolved gases, including oxygen and volatile organic compounds, are removed during primary treatment by vacuum degassing or membrane degassing. Vacuum degassing towers were more common historically, but newer systems have trended towards used of membrane degasification. Ultraviolet (UV) light can used to sterilize purified water during primary treatment though UV treatment can also be left until the polishing stage.
== Epidemiology == Weissenbacher-Zweymüller syndrome affects males and females in the same numbers. About 30 cases have been reported in medical literature. The disorder can be underdiagnosed causing no true frequency in the population.
Following the arrival of the Coalition into power in 2010, he was commissioned to draw up "Plan H" or "No Stone Left Unturned" to stimulate growth in local areas. Since then, 81 out of his 89 recommendations have been adopted. At the 2013 Budget, the Coalition pledged to pool billions of pounds of regional spending into a single fund in a bid to de-centralise public spending and boost economic growth outside London.
Sources: en.wikipedia.org
== Properties == DTT is oxidized by air. So it is normally stored and handled under inert atmosphere to minimize oxidation. The rate of air-oxidation is slower at low temperatures. Oxidized DTT exhibits a strong absorbance peak at 280 nm. Since thiols are less nucleophilic than their conjugate bases, thiolates, DTT becomes a less potent nucleophile as the pH falls. (2S)-2-Amino-1,4-dimercaptobutane (dithiobutylamine or DTBA), a related dithiol reducing agent, somewhat overcomes this limitation of DTT. Tris(2-carboxyethyl)phosphine (TCEP) is an alternative reducing agent that is more stable and effective at low pH, but it is bulky and reduces cystines in folded proteins only slowly. DTT's half-life is 40 hours at pH 6.5 and 1.4 hours at pH 8.5 and 20 °C; its half-life decreases further as temperature increases. The presence of EDTA (ethylenediaminetetraacetic acid) to chelate divalent metal ions considerably extends the half-life of DTT in solution.
== Overview == The MCSGP process consists of several, at least two, chromatographic columns which are switched in position opposite to the flow direction. Most of the columns are equipped with a gradient pump to adjust the modifier concentration at the column inlet. Some columns are connected directly, so that non pure product streams are internally recycled. Other columns are short circuited, so that they operate in pure batch mode. The system is split into several sections, from which every section performs a tasks analogous to the tasks of a batch purification. These tasks are loading the feed, running the gradient elution, recycling of weakly adsorbing site fractions, fractionation of the purified product, recycling of strongly adsorbing site fractions, cleaning the column from strongly adsorbing impurities, cleaning in place and re-equilibration of the column to start the next purification run. All of the tasks mentioned here are carried out at the same time in one unit. Recycling of non-pure side fractions is performed in countercurrent movement.
=== 1996 === 8 September The Mystery of the Cocaine Mummies, about pre-Columbian transoceanic contact theories; German toxicologist Svetlana Balabanova made a discovery in a Munich museum; Svetlana, of the Institute of Forensic Science in Ulm, had invented tests for substances in hair and sweat; people did not believe her; toxicologist John Henry of Guy's Hospital; Egyptologist Ann Rosalie David made independent tests at Manchester Museum; Alfred Grimm of the Egyptian Museum in Munich - Staatliche Sammlung für Ägyptische Kunst; Karnak in Egypt; a French TF1 broadcast in 1981; Michelle Lescot of the National Museum of Natural History, France; Nasri Iskander, chief curator of the Egyptian Museum in Cairo; botanist Sandy Knapp of the Natural History Museum, London; John Baines (Egyptologist); anthropologist Alice Beck Kehoe of Marquette University, and early transatlantic ocean crossings; Martin Bernal of Cornell University. Narrated by Robin Ellis, produced by Hilary Lawson, directed by Sarah Marris, made by TVF 15 September The Great Leveller, about psychosomatic medicine, and how work affects our health, and research on health equity carried out by Richard G.
Cyclotides have been reported to have a wide range of biological activities, including anti-HIV, insecticidal, anti-tumour, antifouling, anti-microbial, hemolytic, neurotensin antagonism, trypsin inhibition, and uterotonic activities. An ability to induce uterine contractions was what prompted the initial discovery of kalata B1. The potent insecticidal activity of cyclotides kalata B1 and kalata B2 has prompted the belief that cyclotides act as plant host-defence agents. The observations that dozens or more cyclotides may be present in a single plant and the cyclotide architecture comprises a conserved core onto which a series of hypervariable loops is displayed suggest that cyclotides may be able to target many pests/pathogens simultaneously.
=== Economics === The sustained-release formulation, Contrave, is marketed by Takeda under license from the combination medication's developer, Orexigen Therapeutics. As of 2015, Orexigen received 20% of net sales from Takeda.
Sources: en.wikipedia.org
== Mechanism and toxicity == κ-Bungarotoxin works as a postsynaptic neurotoxin. The postsynaptic neurotoxin is a prolonged, potentially irreversible, competitive antagonist of neuronal nicotinic acetylcholine receptors (nAChRs). Though α-bungarotoxin specifically binds to muscle nAChRs, κ-bungarotoxin targets the α3 and α4 - though α4 to a lesser extent - subunits of the nAChR in the central and autonomic nervous system, specifically in the avian ciliary ganglia because the α3 subunit of the nAChR is the main ganglionic type. One of Kappa-Bungarotoxin's target sites is the same as that of Alpha-Bungarotoxin, whereas the second target site of the nicotinic receptor is exclusively bound by κ-bungarotoxin. This, because neuronal nAChRs contain a broader variety of subunits than muscle nAChRs. By binding with a high affinity to the acetylcholine binding site of the neuronal nAChRs, Kappa-Bungarotoxin blocks these receptors for an eventual acetylcholine to bind. Normally, activation of the neuronal nAChRs by acetylcholine would release several neurotransmitters and generate inward ion influx, creating action potentials. However, when Kappa-Bungarotoxin is bound to the neuronal nAChRs, it inhibits depolarization at 75 nM and thus synaptic transmission. This blockade leads to the disruption of neuronal communication in the central nervous system and ganglia, causing neuromuscular paralysis and respiratory failure in prolonged κ-bungarotoxin exposure.
The Culture's technology is able to transfer individuals into vastly different body forms, although the Culture's standard form remains fairly humanoid. The Culture holds peace and individual freedom as its core values. A central theme of the series is the ethical struggle it faces when interacting with other societies – some of which brutalise their own members, pose threats to other civilisations, or threaten the Culture itself. It tends to make major decisions based on the consensus formed by its citizens: in one instance, the entire population – a direct democratic vote of trillions – decided that the Culture would go to war with a rival civilisation. Those who objected to the subsequent militarisation broke off from the Culture, forming their own separate civilisation. Another hallmark of the Culture is its ambiguity; in contrast to the other interstellar societies and empires, it is more difficult to define both geographically and sociologically, and it "fades out at the edges".
When young women start out in porn, producers don't send them off for a routine labiaplasty." Although female genital mutilation – the practice of cutting off a woman's labia and sometimes clitoris, and in some cases creating a seal across her entire vulva – is illegal across the Western world, Simone Davis, a professor and gender theorist at Mount Holyoke College in Massachusetts, argues that "when you really look carefully at the language used in some of those laws, they would also make illegal the labiaplasties that are being done by plastic surgeons in the U.S." The World Health Organization (WHO) defines female genital mutilation as "all procedures that involve partial or total removal of the external female genitalia, or other injury to the female genital organs for non-medical reasons." The WHO writes that the term is not generally applied to elective procedures such as labiaplasty. The American College of Obstetricians and Gynecologists (ACOG) published an opinion in the September 2007 issue of Obstetrics & Gynecology that several "vaginal rejuvenation" procedures were not medically indicated, and that there was no documentation of their safety and effectiveness. ACOG argued that it was deceptive to give the impression that the procedures were accepted and routine surgical practices. It recommended that women seeking such surgeries must be given the available surgical-safety statistics, and warned of the potential risks of infection, altered sensation caused by damaged nerves, dyspareunia (painful sexual intercourse), tissue adhesions, and painful scarring.
The two substrates of this enzyme are L-idonic acid and oxidised nicotinamide adenine dinucleotide (NAD+). Its products are 5-oxo-D-gluconic acid, reduced NADH, and a proton. The enzyme can also use the alternative cofactor, nicotinamide adenine dinucleotide phosphate. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-idonate:NAD(P)+ oxidoreductase.
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。
It is a synthetic peptide and a dual agonist of two incretin receptors. It is not a small molecule, and it is not structurally related to the older single-receptor peptide agonists.