A recent study published in PLOS Biology has identified a potential drug that can suppress the appetite, thus helping people lose weight. It is known as camptothecin, which was once used for targeting tumors.
Conducted in obese mice, the research has suggested that a small dose of this medication would release a hormone, which led to a reduced appetite and weight loss.
The doses used for the mice are equivalent to around 1/30 of those used for cancer treatment in human trials.
According to the group of authors from Northwest A&F University in China, camptothecin was extracted from the Camptotheca acuminate plant, which is native to Tibet and China. The bark of this tree has been long used for treating psoriasis, common cold, as well as stomach and liver issues.
The results indicate that camptothecin activates a gene called GDF15, which was released by the body in response to stress.
Previous studies suggested that a high level of this gene would lead to reduced appetites.
In this project, the authors analyzed data from the Connectivity Map for a medication that can increase GDF15 levels in the body. They identified camptothecin.
During the study, the scientists found out that the effect of camptothecin was limited only to GDF15 and GFRAL receptors. As they removed the gene expression of the receptor or used an antibody for neuralization, the appetite was not affected. This verified the link between camptothecin and reduced appetite.
More specifically, the authors injected small amounts of camptothecin to obese mice. After 30 days, both their appetites and weights were reduced.
Although the magnitude of the weight loss is not significant, the effect would be considerable in humans in the long term.
While the research was implemented on mice, it also used human cells to suggest that camptothecin may increase levels of GDF15. This means that a similar mechanism might occur in human bodies.
An interesting finding is that levels of GDF15 in lean mice were not affected by camptothecin, thus resulting in no clear effect on the body weight or appetite.
The results may suggest a potential use of camptothecin for weight loss.
However, several side effects would occur because it belongs to a class of medications called topoisomerase inhibitors. The authors admit that taking them, in the long run, would lead to some safety problems.
A lower dosage may help prevent these problems.