TB-500

What is TB-500?

TB-500 is the synthetic version of a natural compound called thymosin-beta-4. It is a research chemical that has been used in both test-tube and animal studies, along with a small number of human trials, having been found to promote wound healing, muscle repair, joint and tissue strength, and endothelial health.

Thymosin-beta 4 was first identified in 1981 after being isolated from a bovine thymus gland sample . In the early-2010’s, the synthetic version TB-500, which had been developed for veterinary purposes, was rumoured to be rampantly used in competitive horse racing — giving horses receiving it a significant competitive edge against other horses. It was at this time that testing measures to detect TB-500 in race horses began to be developed in earnest.

TB-500, Thymosin beta-4, and all other derivatives thereof are now banned from competitive horse racing, as well as all sporting competitions subject to the Code of the World Anti-Doping Agency (WADA).

However, research on TB-500 is certainly ongoing, and the peptide is of particular interest for researchers studying anti-aging, wound healing, inflammation, cardiovascular health, among other diverse applications.

What Does TB-500 Do?

The primary function of thymosin beta-4 is in cell repair and regeneration. It exhibits most of its actions through the sequestering of actin, which — in the simplest of terms — means that it keeps actin in place. In the event of an injury, thymosin beta-4 would sequester actin at the site of the injury, signalling a cascade of other reactions to occur.

Because actin is a key component of connective tissue, this actin-sequestering action of thymosin-beta 4 helps promote connective tissue healing and regeneration. This activity also signals for the body to begin migrating other stem or progenitor cells to the site where repair is needed. Thymosin beta 4 helps those cells to differentiate into, for example, myocytes (muscle cells), epithelial cells, or other connective or vascular cells to repair the area and rebuild the tissue 

 Muscle. One research area with great potential is the effects of TB-500 on muscle, but not just skeletal muscle. Thymosin-beta 4 appears to exert promising positive effects on both skeletal muscle and cardiac (heart) muscle.

In one 6-month mouse study, researchers found that thymosin-beta 4 administration improved skeletal muscle fibre regeneration in mice who were deficient in dystrophin, a connective tissue protein.

It also may help to protect cardiac muscle and promote repair after damage to the heart through a number of mechanisms .

 Connective tissue. Because of its effects on body proteins, TB-500 may also provide some potential benefits for connective tissue like joints, tendons, and the collagen matrices that anchor the skin, muscles, and organs.

In one animal study, researchers treated incision wounds on rats with thymosin-beta 4. They also kept an untreated control group to compare how the wounds healed differently. In the wounds treated with thymosin-beta 4, the researchers noted that there was minimal scarring present compared to the controls, and that the treated wounds were also much narrower in width.

Upon closer inspection, they were able to determine that this was because the thymosin beta-4 treated wounds had more tightly organized collagen fibres that were more mature, while the controls had more disorganized arrangements of collagen fibres that appeared to be less mature.

Thymosin-beta 4 administration appeared to significantly improve collagen structure and hasten its maturity, resulting in improved wound healing and reduced scarring

 Vasculature and endothelial function. Vasculature refers to blood vessels, and the endothelium is the inner lining of each vessel that helps to regulate blood flow and blood pressure through constriction and dilation. Healthy blood vessels are flexible with highly functioning endothelial linings.

Animal and test-tube models have indicated that thymosin beta-4 can help promote the growth and development of new blood vessels in a process known as neovascularization, but they can also help promote endothelial cell differentiation to help maintain or restore endothelial function in damaged vessels

TB-500 Dosage Calculator

Nonetheless, in the scientific and clinical studies to date, the most common reported dosing range of TB-500 has been 2-5 mg, administered twice weekly, for a duration of 4 to 8 weeks, depending on the nature of the research. Some clinicians favour a higher starting dose for the initial 1 to 2 weeks, followed by a maintenance dose equal to one half of the original dose for the 2 to 6 weeks thereafter.