Research reveals why we lose fat, muscle during infection

economictimes.indiatimes.com:

fat and muscle, a process known as wasting. Salk researchers wanted to know if wasting may help them fight diseases. Researchers in Professor Janelle Ayres' lab discovered the wasting response to T brucei infection in mice occurs in two phases, each regulated by different immune cells.

While fat loss did not benefit the fight against infection, muscle loss did-a surprising clue that some wasting may help manage illness. The findings, published in Cell Reports on July 24, 2023, can inform the development of more effective therapeutics that spare people from wasting and increase our understanding of how wasting influences survival and morbidity across infections, cancers, chronic illnesses, and more. «We often make assumptions that conditions like wasting are bad, since they often coincide with higher mortality rates,» says senior author Ayres, Salk Institute Legacy Chair and head of the Molecular and Systems Physiology Laboratory.

«But if instead we ask, what is the purpose of wasting? We can find surprising and insightful answers that can help us understand the human response to infection and how we can optimize that response.» Defending the body from an invader requires a lot of energy. Prior studies suggested this immune-related energy consumption had the unfortunate consequence of wasting. But Ayres and team were curious to know whether wasting could be beneficial and not just a side effect.

Specialized immune cells called T cells are slow to respond to infections, but when they do respond, they adapt to fight the particular infection. Ayres was interested to know whether it was these T cells causing wasting. If T cells are responsible for the condition, that would indicate wasting is not simply an unproductive side