The key to healthy aging lies in a set of molecules

Irene Vega

El study, recently published in the scientific journal aging cell, has shown that the fat redistribution that occurs during aging is different in middle age. In this sense, the scientific team has observed a predominance of subcutaneous adipose tissue, in contrast to the greater accumulation of visceral adipose tissue that occurs in late stages of aging. “We have proven that calorie restriction improves the metabolic function of adipose tissue in middle age. This fact has led our research group to study the role of microRNAs in the regulation of key genes involved in insulin resistance during aging,” says Gema Medina, researcher and coordinator of the LIPOBETA group at the URJC.

The results of this research suggest that the set of microRNAs discovered, which alter the proper functionality of adipose tissue, could be used to identify the lack of insulin sensitivity in subcutaneous adipose tissue during aging. "In this work we have shown that the metabolic and functional alteration of subcutaneous adipose tissue contributes to insulin resistance in middle age and that this alteration is promoted by a set of microRNAs, whose expression is modified," explains the researcher. Furthermore, these small molecules could be used to establish a more accurate prognosis for healthy aging.

For this study, carried out in mice, a 12-month-old group was used fed ad libitum and another with a 20% calorie restriction for 9 months. Next, subcutaneous and visceral white adipose tissue was extracted from both groups and the microRNA study was carried out. Finally, a biostatistical analysis was performed to evaluate which microRNAs were being modulated in middle age, their target genes, and how caloric restriction modulated said expression.

Therefore, another important finding of this work is that it has been shown that moderate calorie restriction maintained over time improves the expression profile of microRNAs in subcutaneous adipose tissue. This leads to adequate expression of key genes for the maintenance of insulin sensitivity in adipose tissue, which in turn improves metabolic status in midlife.

This work has been carried out in collaboration with the National Cancer Research Center (CNIO), the Príncipe Felipe Research Center and the Sevillian institutions Fundación Progreso y Salud, the Biomedical Institute and the BiER Platform of the Consortium for Networked Biomedical Research in Rare Diseases. (CYBERER).