Everything below concerns incretin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-06. Numbers and descriptions here follow the published literature rather than marketing material.
Retatrutide is an investigational synthetic peptide developed under the code LY3437943, with a backbone derived from glucose-dependent insulinotropic polypeptide. Several non-proteinogenic residues, including alpha-aminoisobutyric acid, appear in that backbone, and a fatty diacid side chain attached through a linker extends circulation time. The molecule carries roughly thirty-nine amino acid units and a total mass near 4.7 kilodaltons. Administration is by subcutaneous injection once weekly. Published work uses both the name retatrutide and the code LY3437943.
Pharmacologically the compound activates three receptors: GLP-1, GIP, and glucagon. GLP-1 and GIP signaling contribute to glucose-dependent insulin release, delayed gastric emptying, and reduced appetite, while glucagon receptor activation is associated with increased energy expenditure and hepatic fat oxidation. The single-molecule design is intended to keep these activities in one peptide rather than combining separate agents. Relative activity at each receptor differs, and the balance between them is a central question in interpretation. The glucagon component is partly offset by incretin-mediated insulin secretion, an interaction that remains incompletely characterized.
Development has progressed from single- and multiple-ascending-dose studies in healthy volunteers into larger randomized trials in adults with obesity, type 2 diabetes, and fatty liver disease. Early reports describe dose-dependent reductions in body weight and improvements in glycemic markers over treatment periods of several months. Whether the glucagon arm adds tolerability cost without added benefit is still debated. Long-term cardiovascular outcomes, effects after treatment stops, and performance in older or comorbid populations are open questions rather than settled findings. Approval status may change, so the current investigational label should be confirmed against regulatory sources.
多肽类化合物的表征通常依赖色谱与质谱联用技术。反相高效液相色谱用于评估纯度与有关物质,质谱用于确认分子量,肽图分析通过酶解碎片比对验证一级结构。这些手段组合使用,可以把目标产物与降解产物或类似物区分开来。单一方法往往不足以完成完整确认。
稳定性研究一般关注脱酰胺、氧化与聚集三类降解路径。脱酰胺多发生在天冬酰胺残基上,氧化常涉及甲硫氨酸与色氨酸,聚集则与浓度、温度以及容器界面接触有关。强制降解实验用于识别分子中较敏感的位点。这些结果会直接影响储存条件的设定与有效期的判断。
冻干粉通常在低温环境下保存,复溶之后需要按指定条件在较短时间内使用。反复冻融和剧烈振荡可能促进聚集,低吸附容器则能减少多肽在管壁上的损失。批号、日期与处理条件的完整记录,是后续复核与问题追溯的基础。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide of about 39 residues | Backbone derived from a GIP sequence |
| Molecular mass | Approximately 4.7 kDa | Peptide chain plus fatty diacid moiety |
| Receptor targets | GLP-1, GIP, glucagon | Unimolecular triple agonist |
| Typical storage temperature | 2 to 8 degrees Celsius | Protect from light; avoid repeated freeze-thaw |
| Common analytical method | LC-MS/MS | Used for plasma quantification and purity checks |
与仅靶向单一受体的同类药物相比,瑞他鲁肽增加胰高血糖素受体成分,理论上可提高能量消耗并改变脂肪分布。临床中观察到的体重变化是否主要来自该额外机制,目前尚无定论。胃肠道反应是该类药物常见不良事件,试验中通过剂量递增和监测进行管理。停药后体重反弹、个体差异和长期耐受性仍需更多数据。
瑞他鲁肽是一种在研合成肽,同时作用于胰高血糖素样肽-1、葡萄糖依赖性促胰岛素多肽和胰高血糖素受体。该分子属于多受体激动剂类别,尚未获得任何监管机构的上市批准。当前临床开发主要针对肥胖和2型糖尿病,研究代号为LY3437943。已确立的信息包括受体靶点和部分中期试验结果;最终疗效、长期安全性和适用人群仍属开放问题。
开发进程从早期单次和多次给药研究推进至大规模后期试验。公开报告显示,参与者在体重和相关代谢指标上出现变化,但完整数据需经同行评审并接受独立复核。试验设计通常包括随机、双盲和对照设置,以区分药物效应与行为干预。监管提交和标签范围尚未确定;长期维持效果与心血管结局仍是开放问题。
The peptide backbone is chemically modified to resist rapid enzymatic breakdown in the body. A fatty acid side chain promotes binding to serum albumin, which slows renal clearance and supports an extended circulation time. These modifications allow less frequent administration than would be possible with an unmodified peptide. The precise contribution of glucagon receptor activation to the overall metabolic effect remains an area of active investigation, because glucagon raises glucose while also increasing energy expenditure.
Development has progressed through early- and mid-stage human studies in adults with obesity and with type 2 diabetes. Published phase 2 data reported reductions in body weight and improvements in glycemic markers over the treatment period. No regulatory agency has approved the compound for any indication, and it remains available only within controlled research settings. Whether benefits observed in trials translate into durable outcomes after treatment stops is not yet established.
Overview of the RNAi process, from Cambridge University's The Naked Scientists Animation of the RNAi process, from Nature NOVA scienceNOW explains RNAi – A 15-minute video of the Nova broadcast that aired on PBS, 26 July 2005 Silencing Genomes Archived 10 August 2019 at the Wayback Machine RNA interference (RNAi) experiments and bioinformatics in C. elegans for education. From the Dolan DNA Learning Center of Cold Spring Harbor Laboratory. RNAi screens in C. elegans in a 96-well liquid format and their application to the systematic identification of genetic interactions (a protocol) 2 American 'Worm People' Win Nobel for RNA Work, from NY Times Molecular Therapy web focus: "The development of RNAi as a therapeutic strategy", a collection of free articles about RNAi as a therapeutic strategy. GenomeRNAi: a database of phenotypes from RNA interference screening experiments in Drosophila melanogaster and Homo sapiens RNAi tools Archived 19 June 2018 at the Wayback Machine Pre-designed and custom RNA Interference tools
==== Steroids ==== The hypothalamus contains neurons that react strongly to steroids and glucocorticoids (the steroid hormones of the adrenal gland, released in response to ACTH). It also contains specialized glucose-sensitive neurons (in the arcuate nucleus and ventromedial hypothalamus), which are important for appetite. The preoptic area contains thermosensitive neurons; these are important for TRH secretion.
==== Scouting America ==== Scouting America refers to WOSM's emblem as the World Crest. It may be worn on Scouting America uniforms as an emblem of the worldwide Scout Movement. Scouting America first used the badge as an award for Scouts and Scouters who participated in an international Scouting event from early 1956 through 1991 with requirements devised by each council. In 1991, Scouting America made it part of the uniform for all Scouts and its International Activity Patch replaced the World Scout Crest as an award.
Microalgae, also referred to as phytoplankton, microphytes, or planktonic algae, constitute the majority of cultivated algae. Macroalgae commonly known as seaweed also have many commercial and industrial uses, but due to their size and specific requirements, they are not easily cultivated on a large scale and are most often taken in the wild. In 2016, aquaculture was the source of 96.5 percent by volume of the total 31.2 million tonnes of wild-collected and cultivated aquatic plants combined. Global production of farmed aquatic plants, overwhelmingly dominated by seaweeds, grew in output volume from 13.5 million tonnes in 1995 to just over 30 million tonnes in 2016.
Sources: en.wikipedia.org
Mahathir reclaimed Carcosa Hill, which had been given to the British by Tunku Abdul Rahman after independence as a sign of good faith, and was home to the British High Commissioner's residence. Mahathir developed a close friendship with Thatcher, leading to strengthened bilateral relations between the two countries during their tenure. Thatcher once praised Mahathir as a truly remarkable national leader and described Malaysia as a textbook example of how to build a prosperous nation. After Thatcher's 1985 visit to Malaysia, bilateral ties improved significantly. Key progress included enhanced trade, particularly in palm oil exports and British technology imports, as well as increased educational cooperation through scholarships for Malaysian students in the UK. Malaysia-UK relations were back on track, leading to Malaysia being chosen to host two major world events — the Commonwealth Heads of Government Meeting in Langkawi in 1989 and the Commonwealth Games in 1998. Mahathir spoke of his good working relationship with Thatcher, saying, "Malaysians should remember that she visited Kuala Lumpur three times — no other British PM has done this before or since." During John Major's visit to Malaysia in September 1993, five memorandums of understanding, involving several billion ringgit, were signed between Malaysian and British companies.
=== Genetic stability === In order for there to be genetic stability within a marijuana strain the breeder has to go through selection and breeding, pinpointing the dominant and recessive genes within the two strains being crossed. After analyzing offspring with the preferred traits a breeder is looking for, the breeder will select the preferred traits and continue to breed those offspring to create the desired final product. Selection is a crucial process for a breeder to create a strain, especially if a client is looking for something with specific plant traits the breeder has to ensure that the hybrid's genetic traits have been closed in enough so unwanted traits aren't expressed in future harvests.
frameshift mutation A type of mutation in a nucleic acid sequence caused by the insertion or deletion of a number of nucleotides that is not divisible by three. Because of the triplet nature by which nucleotides code for amino acids, a mutation of this sort causes a shift in the reading frame of the nucleotide sequence, resulting in the sequence of codons downstream of the mutation site being completely different from the original.
The practical role of protein structure prediction is now more important than ever. Massive amounts of protein sequence data are produced by modern large-scale DNA sequencing efforts such as the Human Genome Project. Despite community-wide efforts in structural genomics, the output of experimentally determined protein structures—typically by time-consuming and relatively expensive X-ray crystallography or NMR spectroscopy—is lagging far behind the output of protein sequences. The protein structure prediction remains an extremely difficult and unresolved undertaking. The two main problems are the calculation of protein free energy and finding the global minimum of this energy. A protein structure prediction method must explore the space of possible protein structures which is astronomically large. These problems can be partially bypassed in "comparative" or homology modeling and fold recognition methods, in which the search space is pruned by the assumption that the protein in question adopts a structure that is close to the experimentally determined structure of another homologous protein. In contrast, the de novo protein structure prediction methods must explicitly resolve these problems. The progress and challenges in protein structure prediction have been reviewed by Zhang.
It has been claimed that Russian security services organized a number of denial of service attacks as a part of their cyber-warfare against other countries, most notably the 2007 cyberattacks on Estonia and the 2008 cyberattacks on Russia, South Ossetia, Georgia, and Azerbaijan. One identified young Russian hacker said that he was paid by Russian state security services to lead hacking attacks on NATO computers. He was studying computer sciences at the Department of the Defense of Information. His tuition was paid for by the FSB. Russian, South Ossetian, Georgian and Azerbaijani sites were attacked by hackers during the 2008 South Ossetia War. In October 2016, Jeh Johnson the United States Secretary of Homeland Security and James Clapper the U.S. Director of National Intelligence issued a joint statement accusing Russia of interfering with the 2016 United States presidential election. The New York Times reported the Obama administration formally accused Russia of stealing and disclosing Democratic National Committee emails. Under U.S. law (50 U.S.C.Title 50 – War and National Defense, Chapter 15 – National Security, Subchapter III Accountability for Intelligence Activities) there must be a formal Presidential finding prior to authorizing a covert attack. Then U.S. vice president Joe Biden said on the American news interview program Meet The Press that the United States will respond. The New York Times noted that Biden's comment "seems to suggest that Mr. Obama is prepared to order – or has already ordered – some kind of covert action".
Sources: en.wikipedia.org
== E == Setsuro Ebashi (1922–2006). Japanese biochemist at the University of Tokyo who discovered troponin. Richard H. Ebright (b. 1959). American molecular biologist at Rutgers University, known for work on protein-DNA interaction, aspects of transcription, and antibacterial drug discovery. John Tileston Edsall (1902–2002). American protein chemist at Harvard, very influential in protein research, and author (with Edwin Cohn) of Proteins, Amino Acids and Peptides. Member Natl. Acad. Sci. USA. Konstantin Efetov (b. 1958). Ukrainian biochemist at Crimea State Medical University, known for work in molecular immunology, evolutionary biology, and biosystematics. Gertrude B. Elion (1918–1999). American biochemist and pharmacologist at Duke University, known for using rational drug design for the discovery of new drugs. Nobel Prize in Physiology or Medicine (1988). Conrad Elvehjem (1901–1962). American biochemist and nutritionist at the University of Wisconsin, known for identifying two vitamins, nicotinic acid, and nicotinamide. Gladys Anderson Emerson (1903–1984). American historian, biochemist and nutritionist at UCLA, the first to isolate Vitamin E in a pure form. Akira Endo (1933–2024). Japanese biochemist at the Tokyo University of Agriculture and Technology. His research into the relationship between fungi and cholesterol biosynthesis led to the development of statin drugs. Foreign associate Natl. Acad. Sci. USA. Donald Engelman (b. 1941). American biochemist at Yale, involved in the creation of new cancer drugs and treatments. Member Natl. Acad. Sci.
=== Examples of intraarticular fractures === Bennett's Fracture intraarticular fracture of the base of the first metacarpal Rolando Fracture comminuted intraarticular fracture of the base of the first metacarpal Calcaneal Fracture fracture of the calcaneus that may extend into the subtalar joint Tibial Plateau Fracture fracture of the proximal portion of the tibia that may extend into the knee joint Pilon Fracture fracture of the distal articular surface of the tibia Distal Radius Fracture fracture of the distal portion of the radius that may extend into the wrist joint Olecranon Fracture fracture of the olecranon process of the ulna at the elbow Femoral Head Fracture fracture of the head of the femur that may extend into the hip joint Some of these fractures such as a Bennett's or Rolando fracture are coined based on their intraarticular involvement, while others such as femoral head fractures, tibial plateau fractures, and distal radius fractures may or may not extend into the joint.
=== Downregulation of genes === Endogenously expressed miRNAs, including both intronic and intergenic miRNAs, are most important in translational repression and in the regulation of development, especially on the timing of morphogenesis and the maintenance of undifferentiated or incompletely differentiated cell types such as stem cells. The role of endogenously expressed miRNA in downregulating gene expression was first described in C. elegans in 1993. In plants this function was discovered when the "JAW microRNA" of Arabidopsis was shown to be involved in the regulation of several genes that control plant shape. In plants, the majority of genes regulated by miRNAs are transcription factors; thus miRNA activity is particularly wide-ranging and regulates entire gene networks during development by modulating the expression of key regulatory genes, including transcription factors as well as F-box proteins. In many organisms, including humans, miRNAs are linked to the formation of tumors and dysregulation of the cell cycle. Here, miRNAs can function as both oncogenes and tumor suppressors.
To perform a selective separation, the distribution ratio of the solute to be extracted must be greater than one, whereas that belonging to the solutes which remain in the aqueous feed must be lower than one. This always yields a separation factor SF > 1. Generally, the effects of acidity and temperature on distribution ratios and the separation factor are investigated because the main species with actinides and lanthanides could be prone to decomplexation upon increasing acidity due to protonation of the ligand or due to increasing temperature. The thermodynamic effects are usually investigated by performing extraction tests at increasing temperature. Furthermore, thermodynamics studies can assess the several alkyl chains of a ligand on its complexation properties towards minor actinides than lanthanides. The extraction processes are based on the complexation of metal ions with lipophilic or hydrophilic ligands. The extracting agent forms a coordination complex with the metal ion as a product of a Lewis acid-base reaction. Ligands are named bases (donors) and contain at least one electron lone pair to donate to metal ions named acids (acceptors). Metal cations in the aqueous feed raffinate are generally solvated by coordinating water molecules through the donor oxygen atoms to form aquo ions
Sources: en.wikipedia.org
As of the mid-2020s retatrutide remains investigational and is not an approved medicine in the United States or the European Union. It has been supplied mainly to participants in clinical trials. Labels and availability can change, so regulatory listings should be checked directly.
Dual agonists act at the GLP-1 and GIP receptors, whereas retatrutide adds glucagon receptor activity on the same peptide. This third activity is the main structural and pharmacological distinction discussed in the literature. Direct head-to-head comparisons remain limited.
Reports usually give the study code LY3437943 alongside the name, the dose in milligrams, and the week at which an endpoint was measured. Percent body-weight change is the most frequent headline measure. Units and populations vary, so comparisons across reports require care.
常用质谱测定分子量,再结合肽图或序列分析验证一级结构。单一检测手段一般难以排除结构相近的类似物。多种方法相互印证更为可靠。