CIB member investigates key treatment for a group of muscle diseases

12-21-2020

Dr. Julio César Cárdenas, who was recently affiliated with the University of California at Santa Bárbara, is part of a study on idiopathic inflammatory myopathies, which includes dermatomyositis, which still does not have an explanation about its origin. Thus, the academic participated in the first work on mitochondrial function in cells derived from patients, and the results could change the treatment of these pathologies.

For four years, Dr. Julio César Cárdenas, researcher at the Mayor U. Center for Integrative Biology, led a team together with Dr. Carla Basualto from the University of Aysén. Together, they investigated idiopathic inflammatory myopathies, a group of diseases of which three stand out: dermatomyositis, polymyositis and inclusion body myositis.

"Treatment is normally with immunosuppressants, but not all patients respond, which led us to look for the causes of this disease in the privacy of skeletal muscle," explains Dr. Cárdenas.

To better understand the problems that this disease entails, it is necessary to know that the mitochondria is essential for the function of the muscle, providing energy and intracellular signals necessary for its function. "Failures in the mitochondria have been observed in several res pathologies, so we decided to explore their status in cells from patients with this disease," explains the member of the CIB.

It was not easy to carry out this study, from the point of view of coordination. Once the clinical team obtained a biopsy of the patients, they had to transfer it immediately to the laboratory, where under sterile conditions it had to be processed to “obtain a cellular preparation rich in myoblasts, which basically correspond to muscle stem cells that have the ability to grow in a Petri plate in the laboratory ”, Cárdenas details .

"These cells grow slowly and require special culture media that allow them to live, so maintenance and care over time was also a great challenge," he adds.

This is the first time that mitochondrial function has been studied in cells derived from patients. In fact, the generation of this model was one of the greatest challenges of this work. “In these cells we found that the function of the mitochondria was less than normal. Then we explored whether the decrease in mitochondrial function was responsible for the pathological phenotype, however we found that this functional decrease of the mitochondria was a physiological adaptation of the muscle cells that allows it to maintain its viability. The activation of the mitochondria caused an increase in cell death and, if it occurs in a patient, it will aggravate his condition ”, clarifies Dr. Cárdenas, who was recently affiliated with the University of California at Santa Bárbara, which will allow establishing alliances with the University Greater in the future, especially with the area responsible for the generation of molecules with potential therapeutic effect.

The incidence in Chile of idiopathic inflammatory myopathies is 5.8 per 100,000 inhabitants, and this finding puts a warning note in relation to therapeutic interventions that can increase mitochondrial function. Thanks to this research, changes could be made in the diets of patients, to help them in their recovery.

Source: https://www.diariomayor.cl/ind...