Aging is associated with the development of two ubiquitous, detrimental pathologies, vascular calcification and amyloidosis. These pathologies are characterized by the accumulation of toxic aggregates in the vessel extracellular matrix (ECM) in the form of crystalline calcium and phosphate mineral or insoluble protein fibrils, respectively. These aggregates impact ECM integrity, drive vascular stiffening, and can also cause cell death and phenotypic change in the cells that interact with them. The deposition of both calcification and amyloid requires a nucleus that can mediate the mineralization of calcium and phosphate, or amyloid aggregation from precursor proteins or peptides. Emerging evidence suggests that changes in the composition of the ECM associated with cellular senescence, as well as extracellular vesicle (EV) release, cargo-loading, trapping, and aggregation within the ECM, are common and synergistic mechanisms that regulate the development of these pathologies. Importantly, vascular smooth muscle cells (VSMCs) orchestrate the formation of both pathologies that commonly co-occur in the aging vasculature. Here, we outline the commonalities and differences in what is known about the genesis of calcification and amyloid, and highlight key questions and areas that remain unknown and require further investigation. The complex relationship between senescence, EVs, and the ECM, mediated by VSMCs, which drives the accumulation of HA and amyloid, could be a target for therapeutic intervention.
Aging represents a complex biological progression affecting the entire body, marked by a gradual decline in tissue function, rendering organs more susceptible to stress and diseases. The human heart holds significant importance in this context, as its aging process poses life-threatening risks. It entails macroscopic morphological shifts and biochemical changes that collectively contribute to diminished cardiac function. Among the numerous pivotal factors in aging, mitochondria play a critical role, intersecting with various molecular pathways and housing several aging-related agents. In this comprehensive review, we provide an updated overview of the functional role of mitochondria in cardiac aging.
Aging is a major risk factor for atherosclerosis and cardiovascular disease (CVD). Two major age-associated arterial phenotypes, endothelial dysfunction and large elastic arterial stiffness, are autonomous predictors of future CVD diagnosis and contribute to the progression of CVD in older adults. Senescent cells lose the capacity to proliferate but remain metabolically active and secrete inflammatory factors termed senescence-associated secretory phenotype (SASP), leading to an increase in inflammation and oxidative stress. Accumulation of senescent cells is linked with the progression of age-related diseases and has been known to play a role in cardiovascular disease. In this brief review, we describe the characteristics and mechanisms of senescent cell accumulation and how senescent cells promote endothelial dysfunction and arterial stiffness. We focus on a range of novel therapeutic strategies aimed at reducing the burden of endothelial dysfunction leading to atherosclerosis through targeting senescent cells. Studies have begun to investigate a specific class of drugs that are able to selectively eliminate senescent cells, termed senolytics, which have shown great promise in reversing the aging phenotype and ameliorating pathologies in age-related disorders, creating a new opportunity for aging research. Generating therapies targeting the elimination of senescent cells would improve health span and increase longevity, making senolytics a promising therapy for cardiovascular diseases.