Atherosclerosis in Sjögren's syndrome: evidence, possible mechanisms and knowledge gaps.

Inflammation has been associated with higher cardiovascular risk in rheumatic autoimmune diseases like rheumatoid arthritis (RA) and systemic lupus erythematosus. More recently, primary Sjögren's syndrome (pSS) was also demonstrated as an independent risk factor for cardiovascular disease, emerging as a new interesting model to study atherosclerosis in autoimmune diseases. Patients with pSS have a higher prevalence of developing traditional cardiovascular risk factors like hypertension and dyslipidaemia predisposing for endothelial dysfunction and premature atherosclerosis. However, the disease-specific mechanisms for premature atherosclerosis in pSS are not fully understood. The aim of this review was to critically analyse the current literature on cardiovascular risks in pSS and to discuss the traditional and disease-associated risk factors. We also suggest possible new mechanisms that should be explored in future research to close the current knowledge gaps on the association of pSS, premature atherosclerosis, and clinical cardiovascular disease.

Gingipains: Critical Factors in the Development of Aspiration Pneumonia Caused by Porphyromonas gingivalis.

Aspiration pneumonia is a life-threatening infectious disease often caused by oral anaerobic and periodontal pathogens such as Porphyromonas gingivalis. This organism produces proteolytic enzymes, known as gingipains, which manipulate innate immune responses and promote chronic inflammation. Here, we challenged mice with P. gingivalis W83 and examined the role of gingipains in bronchopneumonia, lung abscess formation, and inflammatory responses. Although gingipains were not required for P. gingivalis colonization and survival in the lungs, they were essential for manifestation of clinical symptoms and infection-related mortality. Pathologies caused by wild-type (WT) P. gingivalis W83, including hemorrhage, necrosis, and neutrophil infiltration, were absent from lungs infected with gingipain-null isogenic strains or WT bacteria preincubated with gingipain-specific inhibitors. Damage to lung tissue correlated with systemic inflammatory responses, as manifested by elevated levels of TNF, IL-6, IL-17, and C-reactive protein. These effects were unequivocally dependent on gingipain activity. Gingipain activity was also implicated in the observed increase in IL-17 in lung tissues. Furthermore, gingipains increased platelet counts in the blood and activated platelets in the lungs. Arginine-specific gingipains made a greater contribution to P. gingivalis-related morbidity and mortality than lysine-specific gingipains. Thus, inhibition of gingipain may be a useful adjunct treatment for P. gingivalis-mediated aspiration pneumonia.