By Andrea Hargraves 
Obesity promotes chronic low-grade inflammation that leaves the immune system on constant alert, generating a series of false alarms to the body's defense system, and thus premature aging of immune cells.
This phenomenon, which scientists call premature immunosenescence, contributes to a higher incidence of infectious or even chronic degenerative diseases, such as diabetes, atherosclerosis, and other cardiovascular diseases.
In addition to persistent levels of inflammation, obesity can also lead to metabolic changes, especially those associated with lipid (fat) molecules, another mechanism shown to be involved in the development of type 2 diabetes and other chronic non-communicable diseases.
Studies conducted by researchers at the State University of Campinas (Unicamp), with support from Fabisp, showed that a 16-week physical training protocol – which combined weight training and aerobic exercise – was able to reverse both problems associated with obesity.
“In addition to reducing abdominal circumference and increasing strength and lean mass, the training protocol alone, i.e. without food or diet control, reverses the process of premature aging of immune cells and changes in fat metabolism, thus serving as an ineffective alternative.” – Pharmacological treatment of two factors that are significantly associated with the development of chronic diseases. “These are important results that show, once again, the key role of the muscle as an endocrine organ,” says Claudia Cavaglieri, coordinator of the Exercise Physiology Laboratory (Fisex) at the Faculty of Physical Education at Unicamp.
As the researcher explains, the reversal is only possible because active muscle tissue releases substances known as myokines or exercines, which act on various mechanisms throughout the organism.
“Muscle has an important endocrine role. Cross-training changes body composition, generates visceral fat loss and lean mass gain, and improves fat metabolism and mitochondrial function.” [das organelas que produzem energia para as células]“As well as reducing inflammation, thus promoting improvements in health markers.”
In cases of obesity, mitochondria are unable to convert fat into energy molecules (a chemical reaction known as phosphorylation). “With training, the mitochondria begin to phosphorylate fats. The individual ends up using fats to generate energy and this improves the state of fat metabolism in the body as a whole and contributes to weight loss,” he explains.
In the group studies, the researchers also evaluated markers associated with immunosenescence and lipid metabolism in the same group, consisting of 167 individuals divided into three groups: obese, obese with type 2 diabetes, and healthy individuals without comorbidities. The study participants were between 40 and 60 years old.
In work conducted during postdoctoral studies conducted by Diego Trevisan Brunelli, researchers investigated, in cells of the immune system (T lymphocytes), the expression of gene expression markers of inflammation involved in the premature aging process, as well as markers of cellular senescence.
In another study resulting from the doctoral project of Renata Garbellini Doft, supervised by Julian Griffin, of Imperial College London, in the United Kingdom, lipidomics techniques were used, which identify and quantify the pool of lipids (lipid molecules) in the blood and in samples of adipose tissue of volunteers. (Fat).
It is worth noting that lipids play vital roles in cell membranes, where they act as energy reserves, provide structural support, as hormonal precursors, transport vitamins and enable cell signaling. However, in obesity, fat metabolism is deregulated, leading to the accumulation of fat in the body and abnormal deposition of fat in the liver.
“When we measured gene expression markers related to immunosenescence, we found that although there was a lot of similarity between the indicators presented by overweight and obese participants and those with diabetes, the outcome was very different from lean individuals without comorbidities. “This similarity between overweight and obese diabetics is probably due to the fact that all participants with diabetes were on drug treatment,” explains Cavaglieri.
However, markers of immune senescence partially returned to optimal levels after 16 weeks of training. During this period, participants performed three weekly one-hour training sessions, which included half an hour of weight training and half an hour of running, walking, or cycling on an exercise bike.
The researcher confirms that the relationship between obesity and the factors studied constitutes a vicious circle. “The greater the obesity, the greater the release of fats into the blood, the greater the inflammation, and thus the greater the risk of developing chronic non-communicable diseases,” the researcher tells Fabisp.
“But physical exercise can reverse this situation. It is a simple protocol that has been tested on different population groups and recommended by major medical societies. However, we show that in addition to aesthetic gains, training reverses two processes that are of great importance for health and are associated with obesity.