THE ESSENTIAL
- Proteins, carbohydrates and lipids are the three main families of macronutrients.
- Chemotherapy treatment can be responsible for nausea and vomiting which can temporarily cause weight loss.
There are two kinds of fat: brown fat, which stores nutrients in the form of lipids to burn them, then produce heat and maintain body temperature, and white fat, called “bad fat”, which stores excess calories. in the form of lipids, but without eliminating them.
The presence of microproteins in white and brown fat
Scientists from the Salk Institute in San Diego (USA) recently observed that brown fat and white fat contain thousands of microproteins up to then unknown. They also discovered that a microprotein, named Gm8773, increases appetite in mice. This work was published in the journal Cell Metabolism.
As part of this research, the team used genomics technologies to examine brown, white and tan fat, another type of adipose tissue that bears similarities to brown and white fat, in mouse cells.
The researchers observed 3,877 genes that produce microproteins in white fat and brown fat. For the purposes of the study, they examined the levels of these genes in rodents fed a high-fat Western diet. They then found a link between hundreds of microproteins and changes in the metabolism of adipose tissue.
Gm8773 microprotein would increase appetite
During this work, the scientists focused on the Gm8773 protein, located within the hypothalamus, a brain gland that regulates many body functions. According to them, the localization of the microprotein could increase appetite in mice. To verify their hypothesis, they administered the Gm8773 protein to obese mice. The latter consumed more food compared to the other rodents.
According to the researchers, a human FAM237B gene is similar to Gm8773. This microprotein could therefore act in a similar way in humans, which could promote appetite in people suffering from extreme weight loss, especially those undergoing chemotherapy. “We hope that this resource will be used to generate new experimental hypotheses that the scientific community can test in their own laboratories, and that this work will lead to the identification of new mechanisms in biology”pointed out Chris Barnes, co-author of the study and head of proteomics at Velia Therapeutics.