By the time you finish reading this, you would understand the importance of GW501516 as a tool in biomedical research. You will also discover the reason why drug companies and athletes show great interest in this product.
What is it?
GW501516 also known as GSK–516 or GW1516 is the name of the drug initially discovered by Glaxo Wellcome in 1992. It is a peroxisome proliferator-activated receptor delta (PPAR-δ) agonist developed for drug use and was said to be a potential treatment of dyslipidemia, diabetes, obesity and cardiovascular diseases. As a PPAR-δ modulator, it is said to work at the gene level and act on NHRs or nuclear hormone receptors that are involved in lipid and glucose metabolism. It is also believed to affect the skeletal muscle metabolism and thus, could enhance the performance and endurance of the subject or whoever takes certain dosage of the substance.
What does it do and how does it work?
Glaxo Wellcome began their phase I trials on the substance as a possible treatment for hyperlipidemia on 2000. The potential of GW501516 as a performance and endurance enhancer was shown in a 2004 research paper wherein the dosage of the substance given to laboratory rats were substantially higher than the dosage given by Glaxo. The compound is said to have increased the endurance of the rats and that they have more endurance-type or type1 muscle fibers. Since PPAR-δ is a transcription factor which works at the gene level, having more PPAR-δ translates to a broader range of developmental, physiological and biochemical outcomes.
The rats that were practically doped with the substance displays an endurance that’s substantially on a higher level than of normal laboratory rats. In the 2004 research paper, it’s shown that the doped rats could outrun normal laboratory rats up to three times in the treadmill.
In addition to boosting endurance, regulation of fat metabolism and an increase in muscle gene expression are other potential functions of this substance. When combined, the effect of these various functions implies that the subjects, in this case, the lab rats, are more resistant to obesity despite a high fat diet.
Human Effects and Risks
In the 2004 research paper, the doping of the substance was done in the rat embryo so the effects were not really directly applicable to adult humans. Although the research showed that if the substance was activated in a normal adult lab rat, same gene expression effects could be observed as in the doped lab rat that was genetically altered. This, however, did not provide evidence that the substance could improve and enhance performance in adult rats.
Setting its alleged effect in endurance aside, GW501516 showed a great potential as a medication for obese patients. This is the reason why many pharmaceutical companies are interested in this substance.
Before Glaxo Wellcome abandoned the product in 2007, it was reported that they completed up to two phase II clinical trials.
The company dropped the research and development of the substance because of the increase of susceptibility of the subjects to acquire cancer. The rats that were given the substance for two years resulted to a significant risk of developing cancer. The implication of these findings to a human adult at present is still not clear.
The substance is available online as a tool in biomedical research. Although known for its risks it is also sold as a supplement, under the name Endurobol, taken by athletes and body builders.
Summing everything up, GW501516 has the potential to improve performance and enhance endurance in aerobic sports as evidenced by animal studies. No reliable studies demonstrate that the same effect could be achieved on human applications. Also, long term use of the substance can increase the risk of developing cancer. However, this does not elude the fact that this substance, like other drugs and compounds that can modify cell function, creating great potential in discovering medical breakthroughs.