ADIPOSE TISSUE: WHICH ROLE IN AGING AND LONGEVITY?

Since 2018, we are living in a world where there are more people over age 65 than there are children under five. Predictions indicate, if this trend continues, by the year 2050, the number of people over 65 will be double the number of people under five (1). Consequently, an understanding of the optimal physiological, endocrinological, and anthropometric conditions associated with better health during aging is to be considered a priority topic. In parallel with the increasing aging of the population, there is a parallel increase of overweight and obese individuals among older adults (2). Normal aging involves important changes to body composition, including decreased muscle mass and increased fat mass (3). Basal metabolism, for the majority of the elderly, is the main daily energetic expenditure and its decrease with age provides one explanation for the tendency to gain weight, with age. In addition to this physiological statement, lifestyle changes in aged people and the associated reduction in physical activity level favors weight increase with age. Total body fat peaks at about 65–70 years, while in advanced old age it decreases. Aging, indeed, modifies adipose tissue accumulation and redistribution resulting in accumulation of abdominal fat. These age-related changes alter many physiological functions including inflammation and contribute to age-related diseases such as cardiovascular events, diabetes mellitus, hypertension, stroke, and several types of cancer (4). However, to what extent, the age-related adipose tissue remodeling impacts the health status in elderly is incompletely understood. To highlight and clarify the main age-related changes in adipose tissue and discuss its implications on health status with particular regard to age-related diseases, we dedicated a Research Topic to the alteration of lipid storage, the redistribution and the types of fat, the production of different mediators contributing to a pro-inflammatory status in aging.