New Discovery: A Molecule from Python Blood May Lead to More Effective Weight Loss Therapies

The unusual metabolism of pythons could open new possibilities for healthier weight loss and contribute to the fight against age-related muscle loss, according to a new study. This was reported by Euronews.

In just a few years, new weight loss drugs have transformed the market and helped millions of people, but they are often associated with side effects such as nausea and gastrointestinal discomfort. However, American scientists have discovered a previously unknown molecule in the blood of pythons that sends a signal to the brain that the body has consumed enough food.

Pythons can reach lengths of up to seven meters and swallow extremely large amounts of food at once—such as an entire antelope—after which they can survive for months, and sometimes years, without further food intake. The scientists’ interest is not focused on replicating this diet, but on the fact that these snakes can alternate between prolonged fasting and massive meals without permanent damage to the heart or muscles.

The molecule, named para-tyramine-O-sulphate (pTOS), was identified by Prof. Leslie Leinwand and her team at the University of Colorado Boulder during a study of the digestive systems of non-venomous pythons from Africa, Asia, and Australia. The results, obtained in collaboration with scientists from Stanford Medicine and Baylor University, were published in Nature Metabolism.

The researchers found that shortly after feeding, the python’s heart increases by about 25%, and its metabolism accelerates nearly 4,000 times to support digestion. This process is accompanied by a sharp rise in pTOS in the blood—over 1,000 times. In humans, pTOS levels also rise after eating, but much more moderately—about two to five times.

The increase in pTOS is part of the digestive process. The body uses the amino acid tyrosine, which gut bacteria convert into tyramine. The liver then transforms the tyramine into pTOS, which reaches the brain and signals satiety, thereby suppressing appetite.

Until now, this molecule has remained unnoticed in laboratory studies because the most commonly used experimental animals—mice and rats—do not produce it naturally after feeding.

For comparison, the hormone GLP-1, targeted by drugs such as Ozempic and Wegovy, also creates a feeling of satiety by slowing digestion and regulating blood sugar. However, common side effects of these therapies include nausea, stomach discomfort, and occasionally vomiting.

In animal trials, mice given pTOS consumed less food, and with prolonged administration, they showed lower body weight and a sustained reduction in food intake. These effects occurred without significant changes in physical activity, energy expenditure, or blood sugar levels, which scientists believe makes pTOS promising for future research in the field of obesity.

The discovery reveals a new biological mechanism through which the body senses satiety after eating. It could pave the way for future therapies that naturally reduce hunger and support weight control. Simultaneously, the study highlights the important role of gut bacteria in regulating metabolism and transmitting signals to the brain.

For now, pTOS has only been studied in mice, and its effects in humans have not yet been investigated. The scientists also note another important point: the appetite-suppressing effect may be weakened or absent in people with prediabetes or type 2 diabetes, suggesting that the natural satiety signal does not function as effectively in these conditions.