稳定性 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-08-18 and is reviewed periodically as new material appears.
The peptide activates two G protein-coupled receptors, GIPR and GLP-1R. Binding triggers adenylyl cyclase activity and raises intracellular cyclic AMP in pancreatic beta cells, which potentiates insulin release when glucose is elevated. Signaling in the central nervous system is associated with reduced appetite and lower energy intake, while effects on gastric emptying and glucagon secretion are also reported. Because activity at both receptors is retained, the pharmacological profile is often described as incretin-based rather than selective for a single receptor.
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.
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。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C225H348N48O68 | Approximate composition of the free peptide |
| Molecular weight | Approximately 4813 Da | Calculated for the free base |
| Structural class | Synthetic linear peptide | 39 residues with modified backbone |
| Solubility | Soluble in water and polar solvents | Behavior of the lyophilized solid |
| Typical storage temperature | -20 degrees Celsius or below | Solid form, protected from light |
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.
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.
Characterization of the peptide relies on reversed-phase high-performance liquid chromatography for purity and related-substance profiling, with ultraviolet detection near 214 nanometers. Mass spectrometry confirms molecular mass and reveals modifications such as oxidation or deamidation. Peptide mapping after enzymatic digestion verifies the amino acid sequence, while amino acid analysis supplies compositional data. Circular dichroism and infrared spectroscopy are used to assess secondary structure, particularly the alpha-helical content that influences aggregation behavior in solution.
Common degradation routes include hydrolysis of labile amide bonds, deamidation of asparagine and glutamine residues, oxidation of methionine and tryptophan, and non-covalent aggregation. Aggregates can form during freeze-thaw cycling, at elevated pH, or when peptide concentration is high. Each route produces characteristic chromatographic or mass shifts that are tracked during stability studies. Whether a given minor impurity alters biological activity is often an open question, and specification limits are typically set on identity and purity rather than on functional data for trace species.
溶解操作一般使用注射用水或适宜的水性缓冲液，必要时加入少量助溶剂以改善溶解速度，但应避免剧烈涡旋振荡，因为剪切力可能促进聚集。配制后的溶液在冷藏条件下的稳定时间通常短于固体形态，具体时限取决于浓度、缓冲体系与容器材质。是否加入防腐成分，则取决于用途是否为多次取样。
定量分析的主流方法是反相高效液相色谱联用紫外或质谱检测，利用肽在疏水固定相上的保留行为确定纯度与含量。对于生物基质中的浓度测定，常采用液相色谱串联质谱，并配合固相萃取或蛋白沉淀进行样品前处理。免疫分析法也可使用，但可能受到结构相关肽的交叉反应干扰。
December 13: Constitution of 22 Frimaire Year VIII (establishing the Consulate) grants citizenship only to men over 21, born and residing in France, and registered in their commune's civic registry, effectively excluding women. 1800
In February 2023, French Foreign Minister Catherine Colonna met with President Lula and stated that "Brazil is one of the main actors on the global stage and its comeback is highly expected", highlighting that France and Brazil share a strong, centuries-old relationship. She also said that France supports a Brazilian OECD membership and that both France and the European Union are considering monetary contributions to the Amazon Fund. On 11 February, French president Emmanuel Macron expressed his approval for a peace plan on the Russia-Ukraine war proposed by Lula, which consists of creating a group of countries not involved in the conflict (either directly or indirectly, i.e. by sending weapons to one of the sides) to mediate a peace process. On 3 June 2023, Macron's office said Lula confirmed he would visit Paris in late June as part of the "Summit for a New Global Financial Pact" promoted by France to "tackle the reform of multilateral development banks (MDB), the debt crisis, financing for green technologies, the creation of new international taxes and financing instruments", among other things. On 22 June, president Lula delivered a speech during the Power Our Planet festival in Paris in which he said "actually, those who have polluted the planet over the last two centuries are the same ones who made the Industrial Revolution, and that's why they must pay their debt to the planet Earth" while calling for climate justice to Latin-American, African and Asian peoples and inviting the world to attend the COP30 climate conference in the Brazilian city of Belém.
=== Agonists === AT-121 (Experimental agonist of both the μ-opioid and nociceptin receptors, showing promising results in non-human primates.) Buprenorphine (partial agonist, not selective for NOP, also partial agonist of μ-opioid receptors, and competitive antagonist of δ-opioid and κ-opioid receptors) BU08028 (Analogue of buprenorphine, partial agonist, agonist of μ-opioid receptor, has analgesic properties without physical dependence.) Cebranopadol (full agonist at NOP, μ-opioid and δ-opioid receptors, partial agonist at κ-opioid receptor) Etorphine Lexanopadol MCOPPB (full agonist) MT-7716 Nociceptin Norbuprenorphine (full agonist; non-selective (also full agonist at the MOR and DOR and partial agonist at the KOR); peripherally-selective) NNC 63-0532 Ro64-6198 Ro65-6570 SCH-221,510 SR-8993 SR-16435 (mixed MOR / NOP partial agonist) TH-030418
Sources: en.wikipedia.org
== Related compounds == N-Methyliminodiacetic acid (MIDA), the N-methyl derivative of IDA Imidodiacetic acid, the amino diacetic acid N-(2-Carboxyethyl)iminodiacetic acid, a more biodegradable analogue of NTA N-hydroxyiminodiacetic acid (HIDA), HON(CH2CO2H)2 (registry number = 87339-38-6) See HIDA scan.
== Prevalence == The prevalence of HLA-B27 varies markedly in the global population. In the United States, the estimated prevalence is 6-8%. 4% of North Africans, 2–9% of Chinese, and 0.1–0.5% of persons of Japanese descent possess the gene that codes for this antigen. Among the Sami in Northern Scandinavia (Sápmi), 24% of people are HLA-B27 positive, while 1.8% have associated ankylosing spondylitis, compared to 14-16% of Northern Scandinavians in general. In Finland, an estimated 14% of the population is positive for HLA-B27, while more than 95% of patients with ankylosing spondylitis and approximately 70–80% of patients with reactive arthritis have the genetic marker.
==== Antarctica ==== In 1982, Mahathir discussed the governance of Antarctica at the United Nations Convention on the Law of the Sea (UNCLOS). He emphasized that Antarctica should be regarded as the common heritage of mankind, opposing any unilateral claims of sovereignty and advocating for international cooperation in its management and resource utilization. At the time, there were concerns that minerals could be exploited in Antarctica, and the media regarded Mahathir's stance as the only political challenge ever mounted to the Antarctic Treaty in decades. In 1984, Mahathir stated that while the Antarctic Treaty system had contributed positively, there was a need to establish a broader foundation for international cooperation in Antarctica, and he proposed the formation of a "special committee on Antarctica" to conduct an in-depth study and build consensus on a new administrative framework for the continent and the mechanisms required to achieve it. Later, in October 1999, Malaysia sent four scientists to Antarctica to conduct research, focusing on air pollution as part of Universiti Malaya's air pollution research unit. Then, in November 2001, Malaysia launched a second mission, sending two scientists from Universiti Malaya to conduct research on marine and biological sciences. In February 2002, Mahathir led a Malaysian delegation, including his wife, Siti Hasmah Mohamad Ali, and several cabinet members, on a visit to Antarctica. They travelled from Ushuaia, Argentina, aboard the Russian icebreaker Kapitan Dranitsyn.
Sources: en.wikipedia.org
== History of adipose-derived hormones == It had been shown that adipose tissue secreted some unknown factor that influenced appetite. However, the importance of adipose tissue as an endocrine organ was only fully appreciated in 1995 with the discovery of leptin, the protein product of the Ob gene. Leptin is a strong appetite suppressant that, when depleted, causes early onset severe obesity in humans and in animal models. Low levels of leptin in the blood plasma have been heavily associated with people who have moderate to severe forms of depression. Leptin is known to influence moods and cognition by inducing some structural and functional changes within the hippocampus and prefrontal cortex. Also, leptin has been shown to activate signal transduction pathways associated with dopamine and mTOR, which can increase synaptogenesis. Leptin's role in neuroplasticity is currently still being elucidated, but it has been proven to be active in regions of the brain closely linked to depression. It was found that leptin has antidepressant-like effects similar to that of selective serotonin reuptake inhibitors (SSRIs). The discovery of leptin and its effects on appetite led to hopes of a treatment for obesity and type 2 diabetes, a major disease in the developed world. Unfortunately, clinical studies using leptin as a treatment for obesity in humans failed to show improvement, leading some scientists to conclude that the brain can become resistant to leptin, even at supra-physiological levels (the so-called "ceiling effect"), rendering treatment with leptin ineffective.
Microtox is an in vitro testing system which uses bioluminescent bacteria (Allivibrio fischeri, formerly known as Vibrio fischeri) to detect toxic substances in different substrates such as water, air, soils and sediments. Allivibrio fischeri are non-pathogenic, marine, bacteria that luminesce as a natural part of their metabolism. When exposed to a toxic substance, the respiratory process of the bacteria is disrupted, reducing light output. Allivibrio fischeri have demonstrated high sensitivity across a wide variety of toxic substances. Response to toxicity is observed as a change in luminescence, which is a by-product of cellular respiration. This change can be used to calculate a percent inhibition of Allivibrio fischeri that directly correlates to toxicity.
=== Stem Cells === By generating adhesive proteins like fibronectin, fibroblasts are used within research laboratories to help to culture cells which typically demonstrate low survival rates in vitro. For example, fibroblasts have been utilized to increase the survival rate for human stem cells which easily undergo cell apoptosis. As noted by researchers at the Harvard Stem Cell Institute, dermal cell "human keratinocyte [stem cells] could be propagated in vitro when culture on fibroblast feeder cells." In addition to improving the culture and proliferation of stem cells, dermal fibroblasts can also become stem cells. Although dermal cells demonstrate less plasticity than other fibroblast cell types, researchers can still turn these cells into induced pluripotent cells (IPCs). As noted by researchers within the Harvard Stem Cell Institute, researchers obtained fibroblasts from a mouse with sickle cell anemia and, using a virus, "reprogrammed these cells into pluripotent [stem cells], corrected the genetic deficiency by homologous recombination, and redirected these pluripotent cells toward the hematopoietic lineages, and transplanted these engineered cells to a lethally irradiated mice." The animals which received the fibroblast stem cell treatment exhibited increased activity levels, indicating recovery from the disorder.
Sources: en.wikipedia.org
It is a synthetic linear peptide that acts as a dual agonist at the GIP and GLP-1 receptors. It combines a modified incretin backbone with a fatty diacid side chain that extends its circulation time. It is not a small-molecule drug and is not orally absorbed in its native form.
Single-receptor agents act predominantly at GLP-1R. Tirzepatide retains activity at GIPR, which is expressed in pancreatic islets, adipose tissue, and the central nervous system. The contribution of each receptor to the overall response is still an area of active study, and the relative weight of GIPR signaling in humans is not fully settled.
The fatty diacid moiety binds serum albumin, which reduces renal filtration of the active peptide. Additional resistance to enzymatic breakdown comes from non-natural residues in the backbone. Together these features produce an apparent half-life of about five days and permit weekly dosing intervals.
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。