Pro-Gly-Pro tail comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-09-26. Numbers and descriptions here follow the published literature rather than marketing material.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构，不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
== Discovery and ownership background == On 1 November 2005, Cambridge Antibody Technology (CAT) announced it was acquiring two anti-CD22 immunotoxin products from Genencor, namely GCR-3888 and GCR-8015. Genencor is the biotechnology division of Danisco and the acquisition meant CAT would hire certain former Genencor key employees to be responsible for the development of the programmes. GCR-3888 and GCR-8015 were discovered and initially developed by the National Cancer Institute, which is part of the U.S. National Institutes of Health. Genencor licensed the candidates for hematological malignancies and entered into a Cooperative Research and Development Agreement (CRADA) with the NIH, which will now be continued by CAT. Under the original license agreement with the NIH, CAT gained the rights to a portfolio of intellectual property associated with the programs and would pay future royalties to the NIH. CAT intended to file an Investigational New Drug (IND) application for GCR-8015 in various CD22 positive B-cell malignancies, including Non-Hodgkin lymphoma and chronic lymphocytic leukemia, following a period of manufacturing development which is expected to be complete by the end of 2006 and to support the NCI's ongoing development of GCR-3888 in Hairy cell leukemia (HCL) and pediatric acute lymphoblastic leukemia (pALL). CAT-8015 exhibited a greater affinity for CD22 than its predecessor, CAT-3888 and CAT's language such as "CAT will support the NCI's ongoing development of CAT-3888..." suggested at the time that their focus was on the second generation candidate.
Anti-trans actors employ various strategies in their spread of misinformation around transgender health care by inventing pseudoscientific concepts and attacking professionals and organizations that provide gender affirming care, trying to frame gender-affirming care as "dangerous" or "experimental" or claims that a majority of transgender youth will detransition, something scientists have refuted and named the desistance myth, or can be cured using conversion therapy.
Aroa Biosurgery Limited (formerly Mesynthes Limited) is a regenerative medicine company that develops, manufactures and distributes products for wound healing and soft tissue reconstruction. Aroa Biosurgery is headquartered in Auckland, New Zealand with a US office in San Diego, CA, and is listed on the Australian Securities Exchange (ASX: ARX). The company, originally known as Mesynthes Limited, was founded in 2008 by Veterinarian Surgeon Dr Brian Ward (BVSc). The company develops and commercializes products based on its proprietary ovine forestomach matrix technology platform with products in wound healing (Endoform, Natural, Endoform, Antimicrobial and Symphony) as well as plastics and reconstructive surgery (Myriad Matrix, Myriad Forme, Myriad Morcells, Ovitex PRS) and repair of hernia (Ovitex and Myriad Ultra).
Sources: en.wikipedia.org
=== Caged and cage-free eggs === On November 5, 2015, Panera pledged that it would use only cage-free eggs in all of its stores by 2020. Panera also announced the addition of more plant-based proteins, such as edamame and organic quinoa, to its menu. At the time of the announcement, the company said it was 21% cage-free in the roughly 70 million eggs it used in 2015. In December 2016, it published its third animal welfare progress report, announcing new efforts to improve broiler chicken welfare. In 2021, Panera announced that it had transitioned to cage-free eggs for 65% of its egg supply but not yet the remaining 35%.
== Biography == Franciszek Gajowniczek, a Roman Catholic, was born in Strachomin near Mińsk Mazowiecki. After the reconstitution of sovereign Poland, he moved to Warsaw in 1921, married, and had two sons. He was a professional soldier, a Polish army sergeant, who took part in the defense of Wieluń as well as Warsaw in September 1939 during the 1939 invasion of Poland by Nazi Germany. After the Battle of Modlin Gajowniczek was captured by the Gestapo in Zakopane while crossing the border into Slovakia and sentenced to forced labour in Tarnów.
The α2 receptor couples to the Gi/o protein. It is a presynaptic receptor, causing negative feedback on, for example, norepinephrine (NE). When NE is released into the synapse, it feeds back on the α2 receptor, causing less NE release from the presynaptic neuron. This decreases the effect of NE. There are also α2 receptors on the nerve terminal membrane of the post-synaptic adrenergic neuron. Actions of the α2 receptor include: decreased insulin release from the pancreas increased glucagon release from the pancreas contraction of sphincters of the GI-tract negative feedback in the neuronal synapses - presynaptic inhibition of norepinephrine release in CNS increased platelet aggregation decreases peripheral vascular resistance α2 agonists (see actions above) can be used to treat: hypertension – decrease blood pressure-raising actions of the sympathetic nervous system α2 antagonists can be used to treat: impotence – relax penile smooth muscles and ease blood flow depression – enhance mood by increasing norepinephrine secretion Subtype unspecific β agonists can be used to treat:
Sources: en.wikipedia.org
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。
Semax 对应 ACTH 第 4 至第 10 位的片段，并在两端做了替换与延长，使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物，需要医生开具处方。多数其他国家把它当作研究化合物，不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.