Physical exercise alone reverses premature aging factors and metabolic dysfunction in obese people

Studies conducted at the State University of Campinas have shown that physical training, combining strength training and aerobic exercise, improves lipid metabolism, reduces inflammation and reverses early immunosenescence in obese and diabetic individuals.

By Maria Fernanda Ziegler  |  Agência FAPESP – Obesity promotes chronic low-grade inflammation that keeps the immune system on constant alert, generating a series of false alarms for the body’s defense system and, consequently, 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 conditions.

In addition to constant levels of inflammation, obesity can also trigger metabolic changes, particularly related to fat molecules (lipids), another mechanism that has been implicated in the development of type 2 diabetes and other chronic non-communicable diseases.

Studies conducted by researchers at the State University of Campinas (UNICAMP) in Brazil, with the support from FAPESP, showed that a 16-week physical training protocol – combining strength training and aerobic exercise – was able to reverse the two problems associated with obesity.

“In addition to reducing abdominal circumference and increasing strength and lean mass, the training protocol alone, that is, without dietary control, acted to reverse the process of premature aging of immune cells and changes in lipid metabolism, thus serving as a non-pharmacological treatment for two factors strongly associated with the development of chronic diseases. These are important results that once again show the key role of 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 exertokines, which act through various mechanisms throughout the body. “Muscle plays an important endocrine role. Combined training changes body composition, produces visceral fat loss and lean mass gain, improving lipid metabolism and mitochondrial function [of the organelles that produce energy for cells], as well as reducing inflammation, thereby promoting improvements in health markers,” she comments.

In cases of obesity, the mitochondria are unable to convert fat into energy molecules (a chemical reaction known as phosphorylation). “With training, the mitochondria start phosphorylating fat. So the individual ends up using fat to generate energy, and this improves the body’s overall lipid metabolism and contributes to weight loss,” she explains.

In the group’s studies, the researchers also evaluated markers associated with immunosenescence and lipid metabolism in the same cohort, which consisted of 167 individuals divided into three groups: obese, obese with type 2 diabetes, and healthy individuals without comorbidities. The participants in the studies were between 40 and 60 years of age.

In a study conducted during the postdoctoral studies of Diego Trevisan Brunelli, the researchers examined the expression of inflammatory gene expression markers in immune system cells (T lymphocytes) involved in the process of premature aging, as well as cellular aging markers.

In another study, the result of a doctoral project by Renata Garbellini Duft, under the supervision of Julian Griffin, of Imperial College London in the United Kingdom, lipidomics techniques were used to identify and quantify the set of lipids (fat molecules) in the blood and in samples of the volunteers’ adipose tissue (lipidoma).

It is worth noting that lipids play vital roles in cell membranes, acting as energy reserves, providing structural support, as precursors of hormones, transporting vitamins, and enabling cell signaling. However, in obesity, lipid metabolism is deregulated, leading to the accumulation of body fat and abnormal deposition of lipids in the liver.

“When we measured gene expression markers related to immunosenescence, we found that although there was a lot of similarity between the indices presented by obese and overweight participants with diabetes, the result was completely different from lean individuals without comorbidities. This similarity between the obese individuals and obese diabetics was probably due to the fact that all the diabetic participants were on medication,” explains Cavaglieri.

However, some of the immunosenescence markers returned to optimal levels after the 16 weeks of training. During this period, the participants completed three weekly one-hour training sessions, which included a half-hour of strength training and a half-hour of running, walking or cycling on an exercise bike.

The researcher points out that the relationship between obesity and the two factors studied forms a vicious circle. “The more obesity, the greater the release of fats into the blood, the greater the inflammation and, consequently, the greater the risk of developing chronic non-communicable diseases,” she told Agência FAPESP.

“But physical exercise can reverse this situation. It’s a simple protocol that’s been tested in different populations and is recommended by the main medical societies. We’ve shown, however, that in addition to aesthetic gains, training reverses two processes that are of great relevance to health and are related to obesity,” she emphasizes.

The article “Moderate-intensity Combined Training Induces Lipidomic Changes in Individuals with Obesity and Type 2 Diabetes” can be read at: academic.oup.com/jcem/article/109/9/2182/7629543.

The article “Combined Training Improves Gene Expression Related to Immunosenescence in Obese Type 2 Diabetic Individuals” can be read at: www.tandfonline.com/doi/full/10.1080/02701367.2023.2299716.

Image from Moondance by Pixabay.