A practical reference on heptapeptide: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-06-30. Anything still debated is marked as such rather than presented as settled.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
Semax is supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
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.
== Research == Noribogaine was first described in the scientific literature by at least 1958. It was first identified and described as a metabolite of ibogaine by 1995. The first evaluation of noribogaine in humans was published in 2015. In April 2026, the FDA allowed a Phase I clinical study of noribogaine hydrochloride to proceed in the United States.
In February 2022, the Russian Armed Forces under President Vladimir Putin launched an invasion of Ukraine. After warning for several weeks that an attack was imminent, Biden responded by imposing severe sanctions on Russia and authorizing over $8 billion in weapons shipments to Ukraine. On April 29, he asked Congress for $33 billion for Ukraine, but lawmakers later increased it to about $40 billion. Biden blamed Putin for the emerging energy and food crises. In 2022, Congress approved about $113 billion in aid to Ukraine. In October 2023, the Biden administration requested an additional $61.4 billion in aid for Ukraine for the year ahead, but delays in the passage of further aid by the House of Representatives inhibited progress, with the additional $61 billion in aid to Ukraine added in April 2024. Actually delivered aid often differed from announced levels and was also often delayed. The Government Accountability Office and Pentagon Inspector General found that the Biden administration seemed unaware of the pace of weapons deliveries. Throughout the conflict, Biden consistently refused Ukrainian requests to allow them to utilize weapons against Russian military targets inside Russia. An exception was granted in May 2024 for targets in the vicinity of Kharkiv for "counter-fire" purposes. Biden also blocked access for some weapons systems altogether, typically citing fears of escalation, only to permit deliveries for some weapons later on.
The significant leaks of testimonies in the case are raising legal concerns for the Belgian authorities as they continue their investigation. Kaili's actions had already attracted suspicion among the members of her S&D party before her arrest. Dutch lawmaker Lara Wolters, who served in the European Parliament with the same political group as Kaili, described Kaili's modus operandi in an interview with the EU Scream podcast. According to Wolters, Kaili tried to prevent her from expressing views critical of Qatar during discussions in the European Parliament. Kaili's last known action in favour of Qatar before her arrest was casting a vote in the Civil Liberties Committee (of which she was not a member) in support of a report advocating for visa-free travel to the EU for Qatari citizens. While this vote was allowed under the European Parliament' rules, Kaili should have notified members and parliament staff of her intention to vote in advance, which she failed to do. German member Gabriele Bischoff said that Kaili's vote violated "internal rules".
=== Persistent viruses === Using quantitative polymerase chain reaction (qPCR) and next-generation sequencing (NGS) a maximum of five DNA viruses per individual have been identified. Included were several herpesviruses, hepatitis B virus, Merkel cell polyomavirus, and human papillomavirus 31. Given the reactivation and/or oncogenic potential of these viruses, their repercussion on hematopoietic and malignant disorders calls for further studies.
Metal–organic frameworks (MOFs) are a class of coordination polymers consisting of metal clusters, also known as secondary building units (SBUs), coordinated to organic ligands to form one-, two-, or three-dimensional, typically porous structures. The ligands may be referred to as "struts" or "linkers", such as 1,4-benzenedicarboxylic acid (H2bdc). More formally, a metal–organic framework is a potentially porous extended structure made from metal ions and organic linkers. An extended structure is a structure whose sub-units occur in a constant ratio and are arranged in a repeating pattern. MOFs are a subclass of coordination networks, which is a coordination compound extending, through repeating entities, in one dimension, but with cross-links between two or more individual chains, loops, or spiro-links, or a coordination compound extending through repeating coordination entities in two or three dimensions. Coordination networks further belong to coordination polymers, which is a coordination compound with repeating coordination entities extending in one, two, or three dimensions. Most of the reported MOFs are crystalline compounds, but they can be amorphous, or reflect other disordered phases. In most cases for MOFs, the pores are stable during the elimination of the guest molecules (often solvents) and could be refilled with other compounds. Because of this property, MOFs are of interest for the storage of gases such as hydrogen and carbon dioxide.
Sources: en.wikipedia.org
The flag of Cuba is directly connected with the history of Freemasonry in Cuba. In June 1849, it was designed and constructed in an apartment in New York City by the Venezuelan Narciso López, drawn by the Cuban writer Miguel Teurbe Tolón, and sewn together by Emilia Teurbe Tolón. Others involved were Cirilo Villaverde and his wife Emilia Casanova de Villaverde. Everyone involved in the design and construction of the flag was also associated with Freemasonry. The lone star, the five stripes, and the triangle display Masonic symbolism. The stripes, intentionally reminiscent of Old Glory, also feature three horizontal blue stripes; the first three degrees of the Blue Lodge.
=== Bacterial colonization === Since more oxygen in the wound environment allows white blood cells to produce ROS to kill bacteria, patients with inadequate tissue oxygenation, for example those who developed hypothermia during surgery, are at higher risk for infection. The host's immune response to the presence of bacteria prolongs inflammation, delays healing, and damages tissue. Infection can lead not only to chronic wounds but also to gangrene, loss of the infected limb, and death of the patient. More recently, an interplay between bacterial colonization and increases in reactive oxygen species leading to formation and production of biofilms has been shown to generate chronic wounds. Like ischemia, bacterial colonization and infection damage tissue by causing a greater number of neutrophils to enter the wound site. In patients with chronic wounds, bacteria with resistances to antibiotics may have time to develop. In addition, patients that carry drug resistant bacterial strains such as methicillin-resistant Staphylococcus aureus (MRSA) have more chronic wounds.
Ranked among the top three overall in the fDi Intelligence Global Free Zones of the Year Awards 2024. Ranked among the top two worldwide in the “Sustainable Zones” category of the fDi Intelligence Global Free Zones of the Year Awards 2024. UN Investment Promotion Award 2023 for supporting clean tech and renewable energy. Industrial Strategic Partner Award 2024 from the UAE Ministry of Industry and Advanced Technology (MoIAT). EFQM 6-Star Certification for operational excellence and sustainable development.
== Society and culture == The altered appearance caused by vitiligo can affect a person's emotional and psychological well-being. It may lead to employment difficulties, particularly if vitiligo develops on visible areas of the body, such as the face, hands, or arms. Participating in a vitiligo support group may improve social coping skills and emotional resilience.
Sources: en.wikipedia.org
This work led to the development of an ion mobility-quadrupole-CID-TOFMS instrument by Micromass in the UK and ultimately led Micromass / Waters corporation to develop of the world's first commercial ion mobility-mass spectrometer instrument in 2006. The Synapt, as it is called, incorporates a pre ion mobility quadrupole allowing precursor ion selection prior to IMS separation further enhancing the flexibility of the ion mobility-mass spectrometry combinations. In 2013, Agilent Technologies released the first commercial drift tube ion mobility-mass spectrometer named 6560 with an 80 cm drift tube. Ion funnels are used to improve the ion transmission efficiency. The design thus greatly improved the sensitivity of ion mobility and allowed commercialization. A variation of IMS-MS is differential ion mobility spectrometry-mass spectrometry (DIMS-MS), in which gas phase ions are separated based on their ion mobility in varying strengths of electric fields. This analytical method is currently being advanced by Gary Glish and the Glish Group.
=== Generic names === Metribolone is the generic name of metribolone and its INNTooltip International Nonproprietary Name. It is also known by the name methyltrienolone and its developmental code names R1881, R-1881, RU-1881, and RU1881, and is very commonly referred to by these other names rather than as metribolone in the scientific literature.
== External links == Open source software for calculating SPINA-GBeta and other parameters for endotyping glucose homeostasis. (Permanent DOI), (General information and US mirror) Functions for R and S for calculating SPINA-GBeta, SPINA-GR and SPINA-DI. (Permanent DOI) Package "SPINA" for the statistical environment R
=== Small intestinal submucosa === Small intestinal submucosa (SIS) is submucosal tissue in the small intestines of vertebrates. SIS is harvested (typically from pigs) for transplanted structural material in several clinical applications, typically biologic meshes. They have low immunogenicity. Some uses under investigation include a scaffold for intervertebral disc regeneration. Unlike other scaffold materials, the resorbable SIS extracellular matrix (SIS-ECM) scaffold is replaced by well-organized host tissues, including differentiated skeletal muscle.
Lorazepam serum levels are proportional to the dose administered. Giving 2 mg oral lorazepam will result in a peak total serum level of around 20 ng/mL around two hours later, half of which is lorazepam, half its inactive metabolite, lorazepam-glucuronide. A similar lorazepam dose given intravenously will result in an earlier and higher peak serum level, with a higher relative proportion of unmetabolised (active) lorazepam. On regular administration, maximum serum levels are attained after three days. Longer-term use, up to six months, does not result in further accumulation. On discontinuation, lorazepam serum levels become negligible after three days and undetectable after about a week. Lorazepam is metabolized in the liver by conjugation into inactive lorazepam-glucuronide. This metabolism does not involve liver oxidation, so is relatively unaffected by reduced liver function. Lorazepam-glucuronide is more water-soluble than its precursor, so gets more widely distributed in the body, leading to a longer half-life than lorazepam. Lorazepam-glucuronide is eventually excreted by the kidneys, and, because of its tissue accumulation, it remains detectable, particularly in the urine, for substantially longer than lorazepam.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.