If you have been reading about Thymosin alpha 1 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 2025-09-13. Where a claim depends on a specific study, the study is described rather than over-claimed.
Most published studies on thymosin alpha-1 report changes in immune measurements rather than clinical outcomes, and findings differ across designs and populations. Whether the peptide signals through one defined receptor or through several less specific interactions remains an open question. Its reported circulation half-life of a few hours complicates comparison of dosing schedules across trials. Mechanistic claims are frequently drawn from isolated cell cultures, and how far those results extend to whole organisms is unresolved.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids whose sequence matches the amino-terminal region of prothymosin alpha. The chain is acetylated at its first residue and contains one disulfide bridge between two cysteine residues, which folds the molecule into a compact loop. Its molecular formula, C129H215N33O55, corresponds to a monoisotopic mass of roughly 3,106 daltons. Material used in laboratories is made by solid-phase synthesis rather than isolated from animal tissue.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
| Property | Value | Notes |
|---|---|---|
| Class | Synthetic peptide | 28 residues; not a small-molecule compound |
| Molecular mass | About 3,106 Da | Monoisotopic mass of the unmodified chain |
| N-terminal group | Acetylated serine | Present in both native and synthetic forms |
| Secondary structure | Disulfide-constrained loop | One bridge between two cysteine residues |
| Typical source | Solid-phase synthesis | Early isolates came from bovine thymus extracts |
20世纪70年代，研究者从胸腺提取物中纯化出多种小肽，Tα1是其中被较早表征的一种。最初的制备依赖组织匀浆和层析步骤，产量低且成分复杂。随着固相肽合成技术成熟，实验室和工业界能够生产与天然序列一致的合成版本。合成肽的纯度可达95%以上，并可通过反相高效液相色谱和质谱进行鉴定。这一转变使研究不再依赖动物胸腺来源。
市售的胸腺素α1通常以冻干粉形式提供，溶解后用于注射。其氨基酸组成包括多个酸性残基，因此在中性pH下带负电荷。该肽可溶于水和生理盐水，但在有机溶剂中溶解度有限。储存条件通常为冻干状态下负20摄氏度，溶解后需冷藏并避免反复冻融。常见的同义词包括胸腺肽α1、thymalfasin和Tα1。
胸腺素α1（thymosin alpha 1，Tα1）是一种由28个氨基酸组成的酸性肽，N端被乙酰化，分子量约为3108道尔顿。该肽最早从牛胸腺组织提取物中分离，属于胸腺素组分5的一个成分。其序列在不同哺乳动物中高度保守，提示其具有基本的生物学功能。名称中的“α1”指其在电泳中的迁移位置，并非表示亚型编号。它既存在于胸腺，也存在于脾脏和淋巴结等免疫组织。
Thymosin alpha 1 is approved as a medicine in several countries, including Italy and China, for indications such as chronic hepatitis B and as an immune adjuvant. It is not approved by the United States Food and Drug Administration as a therapeutic product. In research settings the peptide appears in studies of sepsis, vaccine response, and oncology support, often with mixed or inconclusive results. The evidence base is uneven, and reviews note that many trials were small. Regulatory status therefore differs widely between jurisdictions.
Thymosin alpha 1 is a synthetic 28-amino-acid peptide first isolated in 1966 from thymosin fraction 5, a bovine thymus extract. Its chain begins with an acetylated serine residue and ends with asparagine. The native peptide carries a molecular mass near 3,108 daltons. Researchers classify it as an immunomodulatory agent rather than a hormone with a single endocrine target. Early work framed it as a thymus-derived factor that supports T-cell maturation. The synthetic form used in research and clinical products matches the natural sequence.
== Exceptions == Peyote and ayahuasca, which contain mescaline and dimethyltryptamine (DMT), respectively, are exempt in certain spiritual or religious settings. A variety of notable psychedelics, including 4-AcO-DMT (psilacetin), 4-HO-MET, dipropyltryptamine (DPT), 5-MeO-MiPT, 5-MeO-AMT, 2C-EF, 2C-B-FLY, Bromo-DragonFLY, methallylescaline (MAL), ALD-52 (1A-LSD), 1P-LSD, ETH-LAD, and LSZ, among many others, are not explicitly controlled substances nor implicitly controlled isomers of scheduled psychedelics in the United States. However, these psychedelics and others could nonetheless be considered controlled substances if intended for human consumption under the Federal Analogue Act.
==== Deterministic theories ==== Deterministic theories can be divided into two subgroups: if the initial chiral influence took place in a specific space or time location (averaging zero over large enough areas of observation or periods of time), the theory is classified as local deterministic; if the chiral influence is permanent at the time the chiral selection occurred, then it is classified as universal deterministic. The classification groups for local determinist theories and theories based on chance mechanisms can overlap. Even if an external chiral influence produced the initial chiral imbalance in a deterministic way, the outcome sign could be random since the external chiral influence has its enantiomeric counterpart elsewhere. In deterministic theories, the enantiomeric imbalance is created due to an external chiral field or influence, and the ultimate sign imprinted in biomolecules will be due to it. Deterministic mechanisms for the production of non-racemic mixtures from racemic starting materials include: asymmetric physical laws, such as the electroweak interaction (via cosmic rays) or asymmetric environments, such as those caused by circularly polarized light (CPL), quartz crystals, or the Earth's rotation, β-Radiolysis or the magnetochiral effect. Shortwave circularly polarized light, for example, can induce enantiomeric bias because chiral molecules will preferentially absorb either the right-handed or left-handed CPL.
These particles cannot be filtered out before injection, and will accumulate in the body over time, especially in the lungs and eyes, producing various complications such as pulmonary hypertension, an irreversible and progressive disease. The formulation sold under the brand name Methadose (flavored liquid suspension for oral dosing, commonly used for maintenance purposes) should not be injected either. Information leaflets included in packs of UK methadone tablets state that the tablets are for oral use only and that use by any other route can cause serious harm. In addition to this warning, additives have now been included in the tablet formulation to make the use of them by the IV route more difficult. Methadone is also available in ampoules with strength of 50mg/ml & 10mg/ml for IV/IM/SC use in the UK. Prescribing the injectable formulation was more common in the 90s with prescribers reporting that up to 9-10% of all methadone prescription were for ampoules. This practice is much less common nowadays
== Mechanism of action == Like all opioid drugs, ADL-5859 activates opioid receptors, but where as traditional opioids (such as oxycodone) activate the three main receptors (mu, delta, and kappa), ADL-5859 appears to be selective and only activates the delta receptor. with a Ki of 20 nM
According to AASLD guidelines, a liver biopsy may be considered in people with MASLD who are at increased risk of having steatohepatitis with or without advanced fibrosis, but only when all other competing chronic liver diseases are excluded (such as alcoholic liver disease). The presence of metabolic syndrome, MASLD Fibrosis Score (FIB-4), or liver stiffness (as measured by Vibration-controlled transient elastography or MRE) can identify individuals who are at higher risk of steatohepatitis or advanced fibrosis.
Sources: en.wikipedia.org
Breeding crops resistant, or at least less susceptible, to pest attacks. Releasing predators, parasitoids, or pathogens to control pest populations as a form of biological control. Chemical control like releasing pheromones into the field to confuse the insects into not being able to find mates and reproduce. Integrated Pest Management: using multiple techniques in tandem to achieve optimal results. Push-pull technique: intercropping with a "push" crop that repels the pest, and planting a "pull" crop on the boundary that attracts and traps it.
== Sources == Broszat, Martin (1981). The Hitler State: The Foundation and Development of the Internal Structure of the Third Reich. New York: Longman Inc. ISBN 978-0-582-48997-4. Gonschior, Andreas. "Wahlen in der Weimarer Republik". (Elections in the Weimar Republic).
Acetylcysteine or N-acetylcysteine (NAC) is a mucolytic that is used to treat paracetamol (acetaminophen) overdose and to loosen thick mucus in individuals with chronic bronchopulmonary disorders, such as pneumonia and bronchitis. It has been used to treat lactobezoar in infants. It can be taken intravenously, orally (swallowed by mouth), or by inhalation by use of a nebulizer. It is also sometimes used as a dietary supplement. Common side effects include nausea and vomiting when taken orally. The skin may occasionally become red and itchy with any route of administration. A non-immune type of anaphylaxis may also occur. It appears to be safe in pregnancy. For paracetamol overdose, it works by increasing the level of glutathione, an antioxidant that can neutralize the toxic breakdown products of paracetamol. When inhaled, it acts as a mucolytic by decreasing the thickness of mucus. Acetylcysteine was initially patented in 1960 and came into medical use in 1968. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication.
Topilutamide, known more commonly as fluridil and sold under the brand name Eucapil, is an antiandrogen medication which is used in the treatment of pattern hair loss in men and women. It is used as a topical medication and is applied to the scalp. Topilutamide belongs to a class of molecules known as perfluoroacylamido-arylpropanamides. Topilutamide is a nonsteroidal antiandrogen (NSAA), or an antagonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). Topilutamide was introduced for medical use in 2003. It is marketed only in the Czech Republic and Slovakia. The patent for Topilutamide expired in 2020.
Sources: en.wikipedia.org
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.
The single bridge between two cysteine residues holds the chain in a folded loop that influences its shape and its behavior in solution. Loss of the bridge through reduction or oxidation shifts chromatographic retention and is tracked during stability work.
It is a defined 28-residue sequence derived from a larger precursor, whereas many other thymic preparations are mixtures of several polypeptides. Its acetylated amino terminus and single disulfide bridge distinguish it chemically from unrelated thymic extracts.
Cold storage slows the chemical degradation reactions that occur in solution. Lyophilized powder is more stable than reconstituted liquid and tolerates longer storage periods. Repeated temperature cycling should still be avoided because it can drive aggregation and loss of material.