The integration of inflammaging in age-related diseases

Aging is characterized by a morpho-functional adaptation, variably affecting major physiological systems, depending on a complex interaction between genetic, environmental and stochastic factors. This dynamic interaction drives an age-related remodelling of a number of pathways/systems, providing the chance to reach the extreme limit of human life in healthy state which is reflected in the ever-increasing number of centenarians. This conceptualization implies that aging process per se and the development of the most common age-related diseases (ARD) are somewhat separate but must share somehow common set of basic biological mechanisms. One of the features that characterize both processes is the development and progression of an inflammatory state named inflammaging. Notably, inflammaging is characterized by a peculiar presentation, being a chronic, systemic, low grade and therefore for a long time subclinical, inflammatory process. For these reasons, even if the rate of progression of inflammaging is currently recognized as the main force driving aging and one of the main risk factors for clinical morbidity and mortality in the elderly, current knowledge on the causal agents are still incomplete and the "clinical evaluation" of inflammaging has not yet been standardized. Even if a number of biomarkers of inflammaging have been identified, their analysis is not recommended as part of the routine evaluation of elderly patients. This review will aim to describe the concept of inflammaging within several other concepts such as the definition of aging per se and how we integrate it in the context of ARD.