English scientists observed a change in the hepatic metabolic landscape and insulin sensitivity, influencing the risk of diabetes, in response to pulmonary tuberculosis.
- After contracting pulmonary tuberculosis, an immune response is triggered in liver cells and glucose metabolism is altered in mice.
- In humans, a metabolic signature associated with insulin resistance is also observed when people progress to tuberculosis from latent infection.
- “A late diagnosis of tuberculosis” can “therefore favor the progression to diabetes in predisposed individuals.”
Highly contagious, tuberculosis, caused by the bacteria Mycobacterium tuberculosis, is spread by inhaling tiny droplets from the lungs of an infected person. It can affect any part of the body, but mainly affects the lungs. This infectious disease induces chronic inflammation which can disrupt metabolism and damage organs essential to maintaining health, such as the liver. “The extent to which pulmonary tuberculosis can trigger the development of metabolic diseases, such as diabetes, and disrupt liver metabolic function is poorly understood,” according to researchers at the University of Leicester (England).
An immune response in liver cells and impaired glucose metabolism
As part of a study, published in the journal PLOS Pathogensthey decided to use laboratory mouse models of pulmonary tuberculosis to examine the changes that occur in the liver during the early stages of infection. “We found that pulmonary tuberculosis leads to an increase in immune-related signaling pathways in liver cells and that tuberculosis-infected mice show impaired glucose metabolism, specifically signs of reduced sensitivity systemic and hepatic insulin”, can we read in the research.
To go further, the authors then reanalyzed the metabolic data published in humans. Observation: glucose metabolism in the liver was also disturbed. In detail, the team observed a metabolic signature associated with insulin resistance that separated people with TB from healthy adults and evolved over time until progression and recovery from TB.
Tuberculosis: “a late diagnosis” could “promote the progression towards diabetes in predisposed people”
“Our research no longer focuses on the fact that diabetes worsens tuberculosis, but on the possibility that late diagnosis of tuberculosis may contribute to disrupted glucose metabolism and insulin resistance and, therefore , promote progression to diabetes in predisposed individuals. As diabetes compromises drug treatment, our study also supports the idea that metabolic screening should be part of all drug or vaccine trials. declared Andrea Cooperlead author of the research.
In future work, the researchers plan to define the molecular pathways by which the immune response modifies liver metabolism, which could make it possible to create targeted interventions. “We will also study how latent tuberculosis (i.e. infection with the bacterial agent of tuberculosis without significant symptoms) can impact metabolic health in humans.”
