If you have been reading about heptapeptide and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
=== Other uses === A clinical trial comparing its efficacy and tolerability with amitriptyline in the treatment of irritable bowel syndrome showed that tianeptine was at least as effective as amitriptyline and produced fewer prominent adverse effects, such as dry mouth and constipation. Tianeptine has been reported to be very effective for asthma. In August 1998, Dr. Fuad Lechin and colleagues at the Central University of Venezuela Institute of Experimental Medicine in Caracas published the results of a 52-week randomized controlled trial of asthmatic children; the children in the groups who received tianeptine had a sharp decrease in clinical rating and increased lung function. Two years earlier, they had found a close, positive association between free serotonin in plasma and severity of asthma in symptomatic persons. As tianeptine was the only agent known to both reduce free serotonin in plasma and enhance uptake in platelets, they decided to use it to see if reducing free serotonin levels in plasma would help. By November 2004, there had been two double-blind placebo-controlled crossover trials and an under-25,000 person open-label study lasting over seven years, both showing effectiveness. Tianeptine also has anticonvulsant and analgesic effects, and a clinical trial in Spain that ended in January 2007 has shown that tianeptine is effective in treating pain due to fibromyalgia. Tianeptine has been shown to have efficacy with minimal side effects in the treatment of attention-deficit hyperactivity disorder.
There are many mechanisms for the repair of damaged double stranded DNA. PARP1 may function as a synapsis factor in alternative non-homologous end joining. Additionally, it has been proposed that PARP1 is required to slow replication forks following DNA damage and promotes homologous recombination at replication forks that may be dysfunctional. It is possible that PARP1 and PARP3 work together in repair of double-stranded DNA and it has been shown that PARP3 is critical for double-stranded break resolution. There are two hypotheses by which PARP1 and PARP3 coincide. The first hypothesis states that the two (ADP-ribosyl)transferases serve to function for each other's inactivity. If PARP3 is lost, this results in single-strand breaks, and thus the recruitment of PARP1. A second hypothesis suggests that the two enzyme work together; PARP3 catalyzes mono(ADP-ribosyl)ation and short poly(ADP-ribosyl)ation and serves to activate PARP1. The PARPs have many protein targets at the site of DNA damage. KU protein and DNA-PKcs are both double-stranded break repair components with unknown sites of ADP-ribosylation. Histones are another protein target of the PARPs. All core histones and linker histone H1 are ADP-ribosylated following DNA damage. The function of these modifications is still unknown, but it has been proposed that ADP-ribosylation modulates higher-order chromatin structure in efforts to facilitate more accessible sites for repair factors to migrate to the DNA damage.
== Etymology == The name "erythritol" derives from the Greek word for the color red (erythros or ἐρυθρός). The name is adapted from a closely related compound, erythrin, which turns red upon oxidation. Despite its name, erythritol is almost always found in the form of white crystals or powder, and chemical reactions do not turn it red.
Every case is different, and different embalming professionals work in different ways. Common grooming practices may include combing and styling the hair and applying cream or emollient spray to the skin to maintain hydration. The deceased will then be dressed and makeup may be applied to mimic natural coloring or the deceased person's typical styling. Hair gel or baby oil is applied to style short hair; while hairspray is applied to style long hair. Powders (especially baby powder) are applied to the body to eliminate odors, and it is also applied to the face to achieve a matte and fresh effect to prevent oiliness of the corpse. Makeup techniques may include using an airbrush to evenly apply product, using mascara to add volume to eyelashes, filling in eyebrows with pencil, and using lipstick or gloss to add color to the lips. Mortuary cosmeticizing is not done for the same reason as make-up for living people; rather, it is designed to add depth and dimension to a person's features that lack of blood circulation has removed. Warm areas – where blood vessels in living people are superficial, such as the cheeks, chin, and knuckles – have subtle reds added to recreate this effect, while browns are added to the palpebrae (eyelids) to add depth, especially important as viewing in a coffin creates an unusual perspective rarely seen in everyday life. During the viewing, pink-colored lighting is sometimes used near the body to lend a warmer tone to the deceased's complexion.
Sources: en.wikipedia.org
==== Estrogen receptors ==== In addition to its affinity for the androgen receptor, DHEA has also been found to bind to (and activate) the ERα and ERβ estrogen receptors with Ki values of 1.1 μM and 0.5 μM, respectively, and EC50 values of >1 μM and 200 nM, respectively. Though it was found to be a partial agonist of the ERα with a maximal efficacy of 30–70%, the concentrations required for this degree of activation make it unlikely that the activity of DHEA at this receptor is physiologically meaningful. Remarkably however, DHEA acts as a full agonist of the ERβ with a maximal response similar to or actually slightly greater than that of estradiol, and its levels in circulation and local tissues in the human body are high enough to activate the receptor to the same degree as that seen with circulating estradiol levels at somewhat higher than their maximal, non-ovulatory concentrations; indeed, when combined with estradiol with both at levels equivalent to those of their physiological concentrations, overall activation of the ERβ was doubled.
Moxisylyte, also known as thymoxamine, is a drug used in urology for the treatment of erectile dysfunction. It is an α1-adrenergic antagonist. In the United Kingdom, Moxisylyte is marketed as Opilon (Archimedes Pharma UK Ltd) and is used for the short-term treatment of primary Raynaud's syndrome. This is a condition where the fingers and toes become discoloured and is triggered by responses to cold, or emotional distress. Opilon tablets help by improving blood circulation to the extremities.
On May 6, 2024, Sanders announced his candidacy for a fourth Senate term. A poll just a few weeks earlier found that more than half of respondents wanted him to seek reelection. Sanders faced Republican nominee Gerald Malloy, who ran against Senator Peter Welch in 2022. Sanders was reelected and has said this term will likely be his last.
[NH4]2CO3 + CaSO4 → [NH4]2SO4 + CaCO3 Ammonium sulfate occurs naturally as the rare mineral mascagnite in volcanic fumaroles and due to coal fires on some dumps. Ammonium sulfate is a byproduct in the production of methyl methacrylate (CH2=C(CH3)COOCH3).
Antihyperglycemic drug used for diabetes mellitus and treatment of hirsutism associated with insulin resistance (e.g. polycystic ovary syndrome). Metformin appears ineffective in the treatment of hirsutism, although the evidence was of low quality. Spironolactone: An antimineralocorticoid with additional antiandrogenic activity at high dosages.
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.