peptide backbone 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 2026-04-23 and is reviewed periodically as new material appears.
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.
Retatrutide is an investigational synthetic peptide that acts as an agonist at three distinct G protein-coupled receptors. It combines activity at the glucagon-like peptide-1 receptor, the glucose-dependent insulinotropic polypeptide receptor, and the glucagon receptor within a single molecule. This multi-receptor profile distinguishes it from earlier incretin-based compounds that engage one or two of these pathways. Researchers designed the molecule to test whether simultaneous activation produces greater metabolic effects than single or dual agonism alone.
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.
retatrutide 是一种人工合成的多肽，设计目标是同时作用于 GIP、GLP-1 与胰高血糖素三种受体。这种三重激动设计试图把多条代谢通路的调节整合进单一分子，而不是只依赖一种肠促胰素受体。分子骨架以天然肽序列为基础，经过非天然氨基酸替换和脂肪酸侧链修饰，以获得更长的作用时间。该方向属于多受体激动剂研究的一部分，与双重激动剂的工作并行推进。
三种受体在能量平衡中的分工并不相同：GLP-1 与 GIP 受体主要参与胰岛素分泌和食欲调节，胰高血糖素受体则与能量消耗及肝糖输出相关。同时激活三者可能产生叠加效应，也可能出现相互制约，具体结果取决于受体亲和力与组织分布。这种组合在理论上可能同时影响体重与血糖指标，但协同关系的细节仍处在研究阶段。
化学修饰延长了分子在体内的停留时间，使较低频次的给药安排成为可能。脂肪酸侧链通过与白蛋白结合延缓清除，非天然氨基酸则降低酶解速率。这些修饰同时改变分子的溶解性与稳定性，需要在制剂设计和储存条件中一并考虑。修饰引入的免疫原性风险也属于开发过程中需要评估的项目。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Not a small molecule |
| Receptor targets | GLP-1, GIP, glucagon | Triple agonist activity |
| Appearance | White to off-white powder | Lyophilized solid |
| Solubility | Soluble in water | Also in aqueous buffers |
| Storage | −20 °C or below | Protect from light and moisture |
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。
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。
Several questions remain unresolved. It is not yet known whether the compound reduces cardiovascular events or mortality, because outcome studies require long follow-up. The durability of weight reduction after treatment withdrawal is uncertain, and rebound has been observed with other incretin-based therapies. Long-term safety data covering several years are limited. Effects in adolescents, in pregnancy, and in people with significant kidney or liver impairment have not been characterized in published reports.
Randomized studies of retatrutide measure change in body weight as a percentage of baseline, along with absolute weight loss. Glycemic endpoints include hemoglobin A1c and fasting plasma glucose. Investigators also track blood pressure, lipid fractions, and liver fat content to characterize effects beyond weight alone. Trial designs typically use double-blind, placebo-controlled groups with periodic dose escalation, and they record adverse events throughout both treatment and follow-up periods.
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。
临床研究通常测量体重、腰围、空腹血糖、糖化血红蛋白和血脂，并记录不良事件。药代动力学评估关注浓度-时间曲线，药效动力学评估关注代谢标志物变化。体重下降由能量摄入减少、能量消耗变化和脂肪组织重塑共同造成，具体权重仍不明确。研究之间的终点定义和随访时长差异使横向比较复杂。
瑞他鲁肽同时激活GLP-1受体、GIP受体和胰高血糖素受体，这三者均属于B类G蛋白偶联受体。受体激活后主要经cAMP信号通路传递效应。GLP-1成分与食欲抑制和胃排空延缓相关，GIP成分影响脂肪组织与胰岛素分泌，胰高血糖素成分则促进肝糖输出和能量消耗。各受体贡献的相对比例在人体中尚未完全量化。
该分子是经过结构修饰的合成肽，通过脂肪酸侧链与白蛋白结合，从而延长循环时间。皮下给药后，药物逐步释放并分布至组织。降解主要依赖蛋白酶，肾脏清除占次要地位。人体半衰期以天为单位，但准确数值随检测方法和个体差异而变；组织分布与受体占有率仍是开放问题。
boiling flask Also Florence flask. A type of flask, usually made of glass, with a large round body, long neck, and flat bottom, designed especially for heating, boiling, and distilling liquids and to make swirling easy. See also round-bottom flask.
== Naming conventions == Amines are named in several ways. Typically, the compound is given the prefix "amino-" or the suffix "-amine". The prefix "N-" shows substitution on the nitrogen atom. An organic compound with multiple amino groups is called a diamine, triamine, tetraamine and so forth. Lower amines are named with the suffix -amine.
== Early life and education == Pohl earned her master's degree in at Radcliffe College. She graduated in 1991 having majored in English and American literature. Her graduate dissertation considered the works of Flannery O'Connor and Walker Percy. After completing her master's, Pohl started a doctoral research programme in chemistry at the University of Wisconsin–Madison. She has said that she was inspired by her Harvard chemistry professor, Dudley R. Herschbach. Her doctoral research involved the synthesis of carbohydrate-based ligands under the supervision of Laura L. Kiessling. She joined Stanford University as a National Institutes of Health postdoctoral fellow in the research group of Chaitan Khosla.
====== Naloxone distribution ====== Naloxone is a drug used to counter an overdose from the effect of opioids; for example, a heroin or morphine overdose. Naloxone displaces the opioid molecules from the brain's receptors and reverses the respiratory depression caused by an overdose within two to eight minutes. The World Health Organization (WHO) includes naloxone on their "List of Essential Medicines", and recommends its availability and utilization for the reversal of opioid overdoses. Formal programs in which the opioid inverse agonist drug naloxone is distributed have been trialled and implemented. Established programs distribute naloxone, as per WHO's minimum standards, to people who use substances and their peers, family members, police, prisons, and others. These treatment programs and harm reduction centres operate in Afghanistan, Australia, Canada, China, Germany, Georgia, Kazakhstan, Norway, Russia, Spain, Tajikistan, the United Kingdom (UK), the United States (US), Vietnam, India, Thailand, Kyrgyzstan, Denmark and Estonia. Many reviews of the literature support the effectiveness of naloxone based interventions in reducing overdose deaths where it is available at the time of the overdose event.
4'-Methyl-α-pyrrolidinopropiophenone (4-MePPP, MPPP or MαPPP) is a stimulant drug and substituted cathinone. It is structurally very similar to α-PPP, with only one added methyl group in the para position on the phenyl ring. 4-MePPP was sold in Germany as a designer drug in the late 1990s and early 2000s, along with a number of other pyrrolidinophenone derivatives. Although it has never achieved the same international popularity as its better-known relations α-PPP and MDPV, 4-MePPP is still sometimes found as an ingredient of grey-market "bath salt" blends such as "NRG-3".
Sources: en.wikipedia.org
== References == Carlsson, J.; Forssell Aronsson, E; Hietala, SO; Stigbrand, T; Tennvall, J; et al. (2003). "Tumour therapy with radionuclides: assessment of progress and problems". Radiotherapy and Oncology. 66 (2): 107–117. doi:10.1016/S0167-8140(02)00374-2. PMID 12648782. "Radioisotopes in Industry". World Nuclear Association. Archived from the original on 27 February 2013. Retrieved 2 May 2008. Martin, James (2006). Physics for Radiation Protection: A Handbook. John Wiley & Sons. p. 130. ISBN 978-3527406111.
Brazil is a federation composed of 26 states, one federal district, and the 5,571 municipalities. States have autonomous administrations, collect their own taxes and receive a share of taxes collected by the Federal government. They have a governor and a unicameral legislative body elected directly by their voters. They also have independent Courts of Law for common justice. States have the ability to create their own laws and establish their own constitutions but criminal and civil laws can be voted by only the federal bicameral Congress and are uniform throughout the country.
In times of severe political confrontation and radical economic change, members of Mikołajczyk's agrarian movement (the Polish People's Party) attempted to preserve the existing aspects of mixed economy and protect property and other rights. However, after the 1947 elections, the Government of National Unity ceased to exist and the communists moved towards abolishing the post-war partially pluralistic "people's democracy" and replacing it with a state socialist system. The communist-dominated front Democratic Bloc of the 1947 elections, turned into the Front of National Unity in 1952, became officially the source of governmental authority. The Polish government-in-exile, lacking international recognition, remained in continuous existence until 1990.
A raw jalapeño is 92% water, 6% carbohydrates, 1% protein, and contains negligible fat (table). A 100-gram (3+1⁄2 oz) reference serving of raw jalapeños provides 120 kilojoules (29 kcal) of food energy, and is a rich source (20% or more of the Daily Value, DV) of vitamin C, vitamin B6, and vitamin E, with vitamin K in a moderate amount (table). Other micronutrients are low in content (table).
Sources: en.wikipedia.org
In August 2022, the Inflation Reduction Act passed, requiring companies to cap the price of insulin at US$35 per month for Medicare. On November 10, a Twitter account impersonating the pharmaceutical company Eli Lilly and Company—one of the three largest manufacturers of insulin—posted a tweet stating that insulin would be made free. According to The Washington Post, Twitter failed to respond to the company for several hours. The incident resulted in Eli Lilly pulling advertisements from Twitter. United States senator Bernie Sanders used the tweet to highlight the price of insulin as other users began creating satirical accounts jovially apologizing for making insulin free, with one such account writing, "Humalog is now $400. We can do this whenever we want and there's nothing you can do about it". The identity of the user who posted the tweet remained unknown until November 22, when Sean Morrow, a 34-year-old writer for the media organization More Perfect Union, admitted to operating the account and writing the tweet. In a video, Morrow stated that he used the account of the Mothman running for the United States Senate for West Virginia, and put that the account was a parody in its biography. Morrow took the video to detail the history of insulin manufacturing and the monopolization of the insulin industry. Eli Lilly further lowered the price of insulin in March 2023.
In February 2025, Bukele offered Secretary of State Rubio to accept non-Salvadoran deportees from the United States, including convicted American prisoners "of U.S. citizenship and legal residents". Rubio described the offer as the "most unprecedented and extraordinary migratory agreement anywhere in the world". Bukele stated that these "dangerous American criminals" would be incarcerated in CECOT. In March 2025, the United States deported 238 alleged members of the Venezuelan gang Tren de Aragua to El Salvador. Bukele met Trump in the Oval Office in April 2025 where they discussed immigration. Both Trump and Bukele stated they could not unilaterally release Kilmar Abrego Garcia, a migrant deported due to an administrative error.
=== Demographics === Fadas are social groups of unmarried young men, known as samari (singular: saurayi), a status below that of a full adult. It is not directly tied to age; a boy becomes a saurayi after puberty and becomes an adult man after marriage. Thus, a boy may enter a fada as young as 12 or 13, and older members of fadas are in their late twenties. Nigerien culture considers work a requirement for manhood, discouraging idleness. Niger's population has a high growth rate and a high proportion of young people, contributing to unemployment. Youth unemployment is severe in cities. There are few job offerings for university students, who widely choose to remain unemployed rather than take an irrelevant job (although they often take temporary, low-paying jobs). As many samari cannot meet their aspirations to have jobs and families, they are in the situation of waithood, a transition phase before becoming a working adult. A fada may be composed of neighbors or people who attended the same school; most are composed of childhood friends. While most fadas consist of unmarried men who cannot find full-time work, some fadantchés have jobs or are full-time students. In some fadas, a majority of members have jobs, while others, particularly in Niamey, are composed of university students who help each other with classes. Some consist mostly of married men. Fadas evolve as members remain in the group after getting jobs. When a member moves away or gets married, their younger sibling may join the fada; otherwise, a fada may disband once all members are adults.
=== Chemical === Bohrium is the fifth member of the 6d series of transition metals and the heaviest member of group 7 in the periodic table, below manganese, technetium and rhenium. All the members of the group readily portray their group oxidation state of +7 and the state becomes more stable as the group is descended. Thus bohrium is expected to form a stable +7 state. Technetium also shows a stable +4 state whilst rhenium exhibits stable +4 and +3 states. Bohrium may therefore show these lower states as well. The higher +7 oxidation state is more likely to exist in oxyanions, such as perbohrate, BhO−4, analogous to the lighter permanganate, pertechnetate, and perrhenate. Nevertheless, bohrium(VII) is likely to be unstable in aqueous solution, and would probably be easily reduced to the more stable bohrium(IV). The lighter group 7 elements are known to form volatile heptoxides M2O7 (M = Mn, Tc, Re), so bohrium should also form the volatile oxide Bh2O7. The oxide should dissolve in water to form perbohric acid, HBhO4. Rhenium and technetium form a range of oxyhalides from the halogenation of the oxide. The chlorination of the oxide forms the oxychlorides MO3Cl, so BhO3Cl should be formed in this reaction. Fluorination results in MO3F and MO2F3 for the heavier elements in addition to the rhenium compounds ReOF5 and ReF7. Therefore, oxyfluoride formation for bohrium may help to indicate eka-rhenium properties.
== Known members == For a key to the single-letter sequences, see Amino acid § Table of standard amino acid abbreviations and properties. All peptides sequences are assumed to start with NH2- and end with -COOH, unless otherwise stated.
Sources: en.wikipedia.org
Retatrutide is an investigational synthetic peptide that activates three metabolic receptors: GLP-1, GIP, and glucagon. It is being studied for obesity and type 2 diabetes. It has not been approved for clinical use.
Earlier incretin therapies engage one or two receptors. Retatrutide adds glucagon receptor activity, which may raise energy expenditure. Whether this produces larger clinical benefits is still being tested.
It has completed phase 2 trials and moved into later-stage evaluation. No regulator has granted approval. Access outside research settings is not authorized.
指同一个分子能激活 GIP、GLP-1 和胰高血糖素三类受体。它与只激活一到两种受体的同类分子在设计思路上有所区别。这种设计的目的在于覆盖更多代谢调节通路。