How Chronic Inflammation Drives Heart Aging and What Can Stop It

Cardiovascular disease remains the leading cause of death in adults over 65 in the United States, responsible for over 2 million deaths annually in that age group. This landmark review by Spray, Richardson, Tual-Chalot, Spyridopoulos, and colleagues published in Cell Reports Medicine synthesizes the rapidly evolving field of cardiovascular inflammaging—the convergence of chronic low-grade inflammation and biological aging that accelerates heart and vascular disease. The concept was first articulated by Franceschi in 2000 using network theory, and this review builds substantially on that foundation with mechanistic and clinical depth.

The first major mechanism examined is cellular senescence and the senescence-associated secretory phenotype (SASP). Senescent cells—which accumulate with age due to impaired immune clearance—upregulate anti-apoptotic proteins including BCL-2 and BCL-xL via PI3K/Akt pathways, making them resistant to normal cell death. Their SASP output of pro-inflammatory cytokines, chemokines, and proteases chronically reshapes tissue microenvironments. Crucially, the review highlights that even post-mitotic cardiomyocytes can adopt a senescent-like state, independent of replicative exhaustion, contributing to myocardial dysfunction through mitochondrial dysfunction and SASP signaling rather than loss of division capacity.

Immune system aging represents a second major pillar. Hematopoietic stem cells shift toward myeloid differentiation with age, producing an elevated neutrophil-to-lymphocyte ratio (NLR) observed in older individuals that correlates with frailty markers such as reduced grip strength and predicts cardiovascular mortality. In the myocardium specifically, embryonically derived CCR2− macrophages—which support repair and resolution—are progressively replaced by pro-inflammatory monocyte-derived CCR2+ macrophages. Thymic involution simultaneously reduces naive T cell output, narrows T cell receptor diversity, and allows accumulation of dysfunctional memory CD8+ T cells. A key experiment showed that CD8+ T cell depletion reduced atherosclerosis in mice, which was restored only by adoptive transfer of T cells from old—not young—donors, directly implicating T cell aging in vascular disease pathogenesis.

Mitochondrial dysfunction constitutes a third interconnected mechanism. Aging mitochondria produce excess reactive oxygen species, damage their own DNA and RNA, and release these nucleic acids into the cytosol as damage-associated molecular patterns (DAMPs), triggering sterile innate immune activation. Peroxidation of the mitochondrial lipid cardiolipin causes its translocation to the outer mitochondrial membrane, where it directly activates the NLRP3 inflammasome and drives pro-inflammatory cytokine release. Impaired mitophagy perpetuates this cycle. Potential mitochondrial-targeted therapies reviewed include the telomerase activator TA-65, metformin, caffeine, and linoleic acid—all showing preclinical or early clinical promise in the post-MI setting.

Epigenetic changes and gut dysbiosis round out the mechanistic picture. Aging induces global DNA hypomethylation alongside localized hypermethylation of atheroprotective gene promoters, driving vascular inflammation. Atherosclerotic lesions show global hypomethylation, and TET2 mutations—somatic mutations accumulating in hematopoietic cells with age—amplify IL-1β signaling and cardiovascular risk, with canakinumab appearing particularly beneficial in TET2-mutant carriers. The gut microbiome, through production of short-chain fatty acids, TMAO, secondary bile acids, and other metabolites, modulates systemic inflammation and cardiovascular risk; dysbiosis with age reduces beneficial Lactobacillus and Bifidobacterium species while expanding pro-inflammatory taxa. On the therapeutic front, the review discusses colchicine (now guideline-recommended post-MI), IL-6 pathway inhibitors (ziltivekimab in the RESCUE trial), senolytics such as dasatinib plus quercetin, and NAD+ precursors targeting mitochondrial function, providing a comprehensive roadmap of the therapeutic landscape.