immunomodulatory peptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-08-17. Anything still debated is marked as such rather than presented as settled.
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。
The peptide is generated in cells by cleavage of prothymosin alpha, a larger acidic protein encoded by the PTMA gene. Prothymosin alpha is expressed in many tissues, not only in the thymus, and its functions include nuclear roles in chromatin-related processes. The 28-residue fragment corresponds to the N-terminal portion of that precursor. How the cleavage occurs and how the fragment's concentration is regulated remain open questions; circulating amounts are small and difficult to measure reliably with routine assays.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
| Property | Value | Notes |
|---|---|---|
| 化学分类 | 线性肽 | 由28个氨基酸组成 |
| 分子量 | 约3108 Da | 合成版本一致 |
| 外观 | 白色至类白色粉末 | 冻干品 |
| 溶解度 | 易溶于水 | 微溶于有机溶剂 |
| 储存温度 | -20°C（冻干） | 溶解后2-8°C |
Immune signaling studies link thymosin alpha 1 to Toll-like receptor pathways, particularly TLR2 and TLR9, on dendritic cells and other antigen-presenting cells. Activation of these receptors promotes maturation of T cells and increases natural killer cell activity. The peptide shifts cytokine output toward a T helper 1 profile, raising interferon gamma and interleukin 2 while modulating interleukin 10. Whether these effects translate into clinical benefit for any specific disease remains a subject of debate. Reported outcomes vary across trials and populations.
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.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
Thymosin beta-4 is a separate 43-residue peptide that binds actin and participates in cell migration; it shares no sequence similarity with thymosin alpha-1 despite the common family name. Other preparative materials, such as thymosin fraction 5 and thymopoietin, contain distinct mixtures or peptides. The shared thymosin label reflects the tissue of origin used in early purification, not a common structural core. Treating these molecules as interchangeable is a frequent source of confusion in laboratory reports and in popular summaries alike.
Thymosin alpha-1 is a synthetic peptide of 28 amino acid residues that corresponds to a naturally occurring fragment first isolated from thymus tissue. Its chain is acetylated at the amino terminus, a modification that shields the peptide from rapid cleavage by aminopeptidases. The molecule carries a net negative charge at physiological pH and dissolves freely in water. Researchers classify it as an immune-modulating agent rather than a classical hormone, because it acts on several cell types of both the innate and the adaptive immune system.
== Synthesis == Generally, synthesis of the characteristic scaffold of ebselen, the benzoisoselenazolone ring system, can be achieved either through reaction of primary amines (RNH2) with 2-(chloroseleno)benzoyl chloride (Route I), by ortho-lithiation of benzanilides followed by oxidative cyclization (Route II) mediated by cupric bromide (CuBr2), or through the efficient Cu-catalyzed selenation / heterocyclization of o-halobenzamides, a methodology developed by Kumar et al. (Route III).
Most bacteria have a single circular chromosome that can range in size from only 160,000 base pairs in the endosymbiotic bacteria Carsonella ruddii, to 12,200,000 base pairs (12.2 Mbp) in the soil-dwelling bacteria Sorangium cellulosum, to 16.0 Mbp in another soil-dwelling bacteria, Minicystis rosea. There are many exceptions to this; for example, some Streptomyces and Borrelia species contain a single linear chromosome, while some bacteria including species of Vibrio contain more than one chromosome. Some bacteria contain plasmids, small extra-chromosomal molecules of DNA that may contain genes for various useful functions such as antibiotic resistance, metabolic capabilities, or various virulence factors. Whether they have a single chromosome or more than one, almost all bacteria have a haploid genome. This means that they have only one copy of each gene encoding proteins. This is in contrast to eukaryotes, which are diploid or polyploid, meaning they have two or more copies of each gene. This means that unlike humans, who may still be able to create a protein if the gene becomes mutated (since the human genome has an extra copy in each cell), a bacterium will be completely unable to create the protein if its gene incurs an inactivating mutation. Bacterial genomes usually encode a few hundred to a few thousand genes. The genes in bacterial genomes are usually a single continuous stretch of DNA. Although several different types of introns do exist in bacteria, these are much rarer than in eukaryotes.
At the other extreme, a very large molecule that cannot penetrate any the smaller pores can enter only the interparticle volume (~35% of the column volume) and elutes earlier when this volume of mobile phase has passed through the column. The underlying principle of SEC is that particles of different sizes elute (filter) through a stationary phase at different rates. This results in the separation of a solution of particles based on size. Provided that all the particles are loaded simultaneously or near-simultaneously, particles of the same size should elute together. However, as there are various measures of the size of a macromolecule (for instance, the radius of gyration and the hydrodynamic radius), a fundamental problem in the theory of SEC has been the choice of a proper molecular size parameter by which molecules of different kinds are separated. Experimentally, Benoit and co-workers found an excellent correlation between elution volume and a dynamically based molecular size, the hydrodynamic volume, for several different chain architecture and chemical compositions. The observed correlation based on the hydrodynamic volume became accepted as the basis of universal SEC calibration. Still, the use of the hydrodynamic volume, a size based on dynamical properties, in the interpretation of SEC data is not fully understood. This is because SEC is typically run under low flow rate conditions where hydrodynamic factor should have little effect on the separation.
Asparagopsis, a seaweed native to Australia, contains bioactives that interrupt the microbes in a cow's stomach that form methane. It is the most efficient natural methane supplement available for livestock – capable of reducing methane emissions by more than 80 per cent in controlled conditions. Asparagopsis can be included in feed and supplements as a stabilised freeze-dried powder, or in an edible oil. FutureFeed research has included the supplement in feedlot and dairy total mixed rations (TMR) and dairy cows supplemented twice daily at milking. A decade of science has shown this to be a safe and effective feed ingredient for livestock. Research into livestock methane production has shown that up to 12% of energy that fodder produces during digestion is lost as methane gas emissions, primarily from belching. It is a common misconception that the majority of methane emissions from livestock is through flatulent gas. Flatulent gas contributes to less than 10% of methane emissions as opposed to belching which contributes up to 95%. This is caused by bacteria living within the first stomach, known as the rumen, which serves as a 'fermentation tank' to effectively break down nutrients during digestion. Methane production represents an inefficiency of energy conversion that would otherwise contribute to the productive metabolism of livestock, such as milk, muscle or wool production. Productivity improvements are directly related to the quality of feed that is ingested.
Polyendocrine metabolic ovarian syndrome (PMOS), previously called polycystic ovary syndrome (PCOS), is the most common hormonal disorder in women of reproductive age. PMOS is diagnosed when a woman has at least two of the following three features: irregular menstrual periods, high testosterone or related symptoms (like excess facial hair), or an excess of antral ovarian follicles on ultrasound. Persons with PMOS are not more likely than those without to have true ovarian cysts. A blood test for high levels of anti-Müllerian hormone can replace the ultrasound in the diagnosis. Other symptoms associated with PMOS are heavy periods, acne, difficulty getting pregnant, and patches of darker skin. The exact cause of PMOS remains uncertain. There is a clear genetic component, but environmental factors are also thought to contribute. PMOS occurs in between 5% and 18% of women. The disorder is linked to insulin resistance, which is made worse by obesity. Insulin resistance and related excess insulin levels increase the risk of complications such as type 2 diabetes and liver disease. Those living with PMOS also have higher risk of endometrial cancer.
Sources: en.wikipedia.org
=== No development reported === AB-101 (RJ-101) – topical – alopecia – undefined mechanism of action BRM-421 (GPN-00136, PDSP) – topical – alopecia – cell proliferation stimulant Dimethylcurcumin (ASC-J9, AJ-101) – topical – male pattern baldness – androgen receptor degradation enhancer Lepzacitinib (ATI-1777) – topical – alopecia areata – Janus kinase 1 inhibitor, Janus kinase 3 inhibitor PF-277343 – unspecified – alopecia – undefined mechanism of action Research programme: janus kinase inhibitors - Aclaris Therapeutics/ JAKPharm – unknown – alopecia areata – Janus kinase 3 inhibitors Research programme: skin diseases therapeutics - Quark Pharmaceuticals (QP-AL1; QP-AL2) – unknown – alopecia (chemotherapy-induced) – RNA interference Research programme: stem cell therapeutics - Histostem (Cirrhosis HMScs) – unknown – alopecia – cell replacement Synephrine (AB-102) – topical – alopecia – α1-adrenergic receptor agonist Valproic acid (VPA spray) – topical – male pattern baldness – glycogen synthase kinase 3β inhibitor, Wnt signalling pathway stimulant
== Role in obesity == AgRP induces obesity by chronic antagonism of the MC4-R. Overexpression of AgRP in transgenic mice (or intracerebroventricular injection) causes hyperphagia and obesity, whilst AgRP plasma levels have been found to be elevated in obese human males. Understanding the role AgRP plays in weight gain may assist in developing pharmaceutical models for treating obesity. AgRP mRNA levels have been found to be down regulated following an acute stressful event. Studies suggest that systems involved in the regulation of stress response and of energy balance are highly integrated. Loss or gain of AgRP function may result in inadequate adaptive behavioural responses to environmental events, such as stress, and have potential to contribute to the development of eating disorders. It has been shown that polymorphisms in the AgRP gene have been linked with anorexia nervosa as well as obesity. Some studies suggest that inadequate signalling of AgRP during stress may result in binge eating. Starvation-induced hypothalamic autophagy generates free fatty acids, which in turn regulate neuronal AgRP levels.
Boyer, P.D., Lardy, H. and Myrback, K. (Eds.), The Enzymes, 2nd ed., vol. 7, Academic Press, New York, 1963, p. 85-96. Brosemer RW, Kuhn RW (1969). "Comparative structural properties of honeybee and rabbit alpha-glycerophosphate dehydrogenases". Biochemistry. 8 (5): 2095–105. doi:10.1021/bi00833a047. PMID 4307630. O'Brien SJ, MacIntyre RJ (1972). "The -glycerophosphate cycle in Drosophila melanogaster. I Biochemical and developmental aspects". Biochem. Genet. 7 (2): 141–61. doi:10.1007/BF00486085. PMID 4340553. S2CID 22009695. Warkentin DL, Fondy TP (1973). "Isolation and characterization of cytoplasmic L-glycerol-3-phosphate dehydrogenase from rabbit-renal-adipose tissue and its comparison with the skeletal-muscle enzyme". Eur. J. Biochem. 36 (1): 97–109. doi:10.1111/j.1432-1033.1973.tb02889.x. PMID 4200180. Albertyn J, van Tonder A, Prior BA (1992). "Purification and characterization of glycerol-3-phosphate dehydrogenase of Saccharomyces cerevisiae". FEBS Lett. 308 (2): 130–2. Bibcode:1992FEBSL.308..130A. doi:10.1016/0014-5793(92)81259-O. PMID 1499720. S2CID 39643279. Koekemoer TC, Litthauer D, Oelofsen W (1995). "Isolation and characterization of adipose tissue glycerol-3-phosphate dehydrogenase". Int. J. Biochem. Cell Biol. 27 (6): 625–32. doi:10.1016/1357-2725(95)00012-E. PMID 7671141.
The generation of transgenic protocols (whole organism, cell or tissue specific, tagged with reporter genes) has increased the level of information gained by studying these fish. GM fish have been developed with promoters driving an over-production of growth hormone for use in the aquaculture industry to increase the speed of development and potentially reduce fishing pressure on wild stocks. This has resulted in dramatic growth enhancement in several species, including salmon, trout and tilapia. AquaBounty Technologies, a biotechnology company, have produced a salmon (called AquAdvantage salmon) that can mature in half the time as wild salmon. It obtained regulatory approval in 2015, the first non-plant GMO food to be commercialized. As of August 2017, GMO salmon is being sold in Canada. Sales in the US started in May 2021.
Sources: en.wikipedia.org
它不是经典的内分泌激素，而是一种免疫调节肽。其作用主要通过局部免疫细胞间的信号传递实现，而非经血液循环作用于远隔器官。
天然胸腺素α1主要从胸腺组织提取，也可在脾脏和淋巴结中检出。目前研究和临床使用的多为化学合成版本，不再依赖动物组织。
胸腺素组分5是牛胸腺提取物的粗组分，包含多种肽。胸腺素α1是其中一种被纯化和表征的单一肽，具有明确的28个氨基酸序列。
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.