Background: The risk for cardiovascular disease is multifold higher in patients with the autoimmune disease rheumatoid arthritis, but underlying mechanisms remain poorly defined. We have explored whether patients with rheumatoid arthritis (RA) and patients with coronary artery disease (CAD) share pro-inflammatory effector cells that sustain tissue inflammation, thus maintaining synovial inflammation and atherosclerotic plaque formation. Methods: Tissue cytokines expressed in RA synovial lesions were analyzed by cytokine array technology. Cytokine production in macrophages was verified with RT-PCR, immunohistochemistry and flow cytometry. Mitochondrial function was evaluated by Seahorse analyzer. Results: In highly inflamed synovial tissues, 21 of 60 cytokines tested were significantly elevated, with the small cytokine CCL18 being strongly associated with tissue inflammation. Immunohistochemical examination assigned CCL18 to CD68 + tissue macrophages in both the atherosclerotic plaque and in rheumatoid synovitis. In monocyte-derived macrophages (MΦ), CCL18 enhanced production of the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α and stimulated production of the tissue-injurious enzyme cathepsin K. Pro-inflammatory effector functions were linked to CCL18 induced activation of mitochondrial metabolism, quantified by oxygen consumption rates and generation of ATP. Macrophage stimulation with recombinant CCL18 resulted in the inactivating phosphorylation of the metabolic sensor GSK-3β. Immunoprecipitation experiments localized GSK-3β to the mitochondrial surface and imaging studies revealed excessive formation of mitochondria-endoplasmic reticulum connections in patient-derived CCL18 hi macrophages. Conclusions: Pro-inflammatory MΦ in CAD and RA patients share a metabolic profile of increased mitochondrial oxygen consumption and ATP production. Mitochondrial activation depends on inactivation of the metabolic sensor GSK-3β and promote pro-inflammatory effector functions, such as production of cytokines and proteases. Inhibiting GSK-3β activation provides a novel therapeutic strategy to suppress pro-inflammatory macrophages in CAD and RA.
Vascular contributions to cognitive impairment and dementia (VCID): A report from the 2018 National Heart, Lung, and Blood Institute and National Institute of Neurological Disorders and Stroke Workshop
Abstract Vascular contributions to cognitive impairment and dementia (VCID) are characterized by the aging neurovascular unit being confronted with and failing to cope with biological insults due to systemic and cerebral vascular disease, proteinopathy including Alzheimer's biology, metabolic disease, or immune response, resulting in cognitive decline. This report summarizes the discussion and recommendations from a working group convened by the National Heart, Lung, and Blood Institute and the National Institute of Neurological Disorders and Stroke to evaluate the state of the field in VCID research, identify research priorities, and foster collaborations. As discussed in this report, advances in understanding the biological mechanisms of VCID across the wide spectrum of pathologies, chronic systemic comorbidities, and other risk factors may lead to potential prevention and new treatment strategies to decrease the burden of dementia. Better understanding of the social determinants of health that affect risks for both vascular disease and VCID could provide insight into strategies to reduce racial and ethnic disparities in VCID.