If you have been reading about Peptide stability 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 2026-02-24. Where a claim depends on a specific study, the study is described rather than over-claimed.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
Thymosin alpha-1 is a synthetic 28-amino-acid peptide whose sequence was first identified in extracts of bovine thymus tissue during the 1970s. The chain carries an acetyl group on its N-terminal serine. Its acidic residue content is high, which produces strong water solubility and an isoelectric point well below neutrality. Material supplied for laboratory and clinical use is manufactured by solid-phase peptide synthesis rather than purified from animal tissue. Different salt forms, such as the acetate, alter the counter-ion content without changing the peptide backbone.
Whether the free 28-residue peptide circulates in human tissue remains debated. The best-documented human source is prothymosin alpha, a larger acidic protein that carries the sequence at its N-terminus. Reports of measurable peptide levels in serum and lymphoid tissue exist, yet some of that signal may come from cross-reacting fragments or from the parent protein. Most reviews therefore treat prothymosin alpha as the established human molecule and describe independent circulation of the small peptide as an unresolved question.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C129H215N33O55 | Calculated for the acetylated 28-residue peptide |
| Appearance | White to off-white powder | Lyophilized solid recovered from aqueous buffer |
| Solubility | Freely soluble in water | Typically dissolved in water or buffer before use |
| Typical storage | -20 C or below, desiccated | Protect from light and avoid repeated freeze-thaw cycles |
| Identity testing | Reverse-phase HPLC with mass spectrometry | Retention time and measured mass confirm the sequence |
Routine handling calls for storage of the lyophilized powder at refrigerated temperatures, away from light, in a sealed container. Working solutions are often prepared in sterile water or buffer and kept cold between uses. Repeated freeze-thaw cycles are generally avoided because they can promote aggregation and loss of material. Laboratories usually record lot number, reconstitution date, and storage conditions so that any change in behavior can be traced to a specific preparation.
Reverse-phase high-performance liquid chromatography is the standard technique for assessing purity and concentration, because the peptide's hydrophobicity allows clean separation from related impurities. Mass spectrometry confirms molecular identity and detects sequence errors or truncations. Amino acid analysis and peptide mapping supply additional structural confirmation when required. Chromatographic purity values reported on certificates of analysis describe the proportion of the main peak and do not by themselves establish biological activity.
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。
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。
Nazi Party election results presents a series of tables that summarize the election results of the National Socialist German Workers' Party (German: Nationalsozialistische Deutsche Arbeiterpartei, NSDAP), usually referred to as the Nazi Party, in German national and state elections, during its existence. They display the number of votes received, the percentage of the vote, the Party's numerical ranking, the number of parliamentary seats won and the change in the number of seats.
== History == In 1983, pioneers of glutathione research, Mary E. Anderson and Alton Meister, were the first to report on the ability of GGC to augment cellular GSH levels in a rat model. Intact GGC, which was synthesised in their own laboratory, was shown to be taken up by cells, bypassing the rate-limiting step of the GCL enzyme to be converted to glutathione. Control experiments with combinations of the constituent amino acids that make up GGC, including L-glutamic acid and L-cysteine, were ineffective. Since this initial work, only a few studies using GGC were performed due to the fact that there was no commercial source of GGC on the market. Subsequently, GGC has become commercially available and studies investigating its efficacy have commenced.
==== Lorcaserin ==== Lorcaserin is the only agent that has completed phase III clinical trials, and achieved US Food and Drug Administration (FDA) approval. However it was later withdrawn from the market in February 2020 due to a higher risk of malignancy in a randomized trial of lorcaserin. Previously approved agents were subsequently removed from the US market. Lorcaserin is a full agonist for 5-HT2C and 5-HT2B receptors and partial agonist for 5-HT2A receptors (75% of the maximal response elicited by serotonin). Lorcaserin is a potent and selective 5-HT2C agonist with rapid oral absorption that shows dose-dependent decrease in food intake and body weight. Lorcaserin affects body weight by producing a negative energy balance through reduced food intake (energy intake) without alterations in energy expenditure and substrate oxidation. Lorcaserin has a high affinity for the 5-HT2C receptors, with 18-fold selectivity over 5-HT2A receptors and 104-fold over 5-HT2B receptors. The predicted blood concentration to stimulate 2A and 2B receptors is approximately 1400-fold for 2B and 250-fold for 2A, above the blood concentration that is required to stimulate the 2C receptors. This functional selectivity is critical to prevent potential side effects and suggests that the theoretical risk of cardiac valvulopathy is very low. Clinical trials have supported this theory since they have not revealed any side effects on heart valves or pulmonary artery pressure like the former obesity drugs.
Sources: en.wikipedia.org
Because of the burning sensation caused by capsaicin when it comes in contact with mucous membranes, it is commonly used in food products to provide added spiciness or "heat" (piquancy), usually in the form of spices such as chili powder and paprika. In high concentrations, capsaicin will also cause a burning effect on other sensitive areas, such as skin or eyes. The degree of heat found within a food is often measured on the Scoville scale. There has long been a demand for capsaicin-spiced products like chili pepper, and hot sauces such as Tabasco sauce and Mexican salsa. It is common for people to experience pleasurable and even euphoric effects from ingesting capsaicin. Folklore among self-described "chiliheads" attribute this to pain-stimulated release of endorphins, a different mechanism from the local receptor overload that makes capsaicin effective as a topical analgesic. Because capsaicin sublimes at 115°C, some precaution is needed when cooking dry or with fats to preserve capsaicin in pungent food.
== Interactions == Due to its effect of reducing stomach acidity, use of pantoprazole can affect absorption of drugs that are pH-sensitive, such as ampicillin esters, ketoconazole, atazanavir, iron salts, amphetamine and mycophenolate mofetil. Additional medications that are affected include bisphosphonate derivatives, fluconazole, clopidogrel, and methotrexate.
Within Socialist Republic of Serbia two autonomous provinces existed: Socialist Autonomous Province of Vojvodina and Socialist Autonomous Province of Kosovo. The central part of the Socialist Republic of Serbia located outside of the two autonomous provinces was generally known as "Serbia proper" ("Uža Srbija"). Geographically SR Serbia bordered Hungary to the north, Romania and Bulgaria to the east and Albania to the south-west. Within Yugoslavia, it bordered SR Macedonia to the south and SRs Montenegro, Bosnia and Herzegovina and Croatia to the west.
=== Dithiols === 1,3-Propanedithiol and 1,2-ethanedithiol are reagents in organic chemistry. Dimercaptosuccinic acid is a chelating agent. Lipoic acid, a naturally occurring modification of 1,3-propanedithiol, is a cofactor for many enzymes. Dithiothreitol is a reagent in biochemistry.
Sources: en.wikipedia.org
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.
No. The two peptides share part of a name but differ in length, sequence, and net charge. Literature searches that treat them as one compound return misleading results.
Solid-phase peptide synthesis is the usual route, and recombinant expression has also been described. Both approaches produce material matching the natural sequence.
It is usually described as an immunomodulatory peptide rather than a classic circulating hormone. No endocrine gland is known to release it as a primary secretory product, and its measured presence in blood is not firmly established.