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Importance: Psoriasis, a chronic inflammatory skin disease associated with accelerated noncalcified coronary burden (NCB) by coronary computed tomography angiography (CCTA), accelerates lipoprotein oxidation in the form of oxidized modified lipoproteins. A transmembrane scavenger receptor for these oxidized modified lipoproteins is lectinlike oxidized low-density lipoprotein receptor-1 (LOX-1), which has been reported to be associated with coronary artery disease. It is unknown whether this receptor is associated with coronary artery disease in psoriasis., Objective: To assess the association between soluble LOX-1 (sLOX-1) and NCB in psoriasis over time., Design, Setting, and Participants: In a cohort study at the National Institutes of Health, 175 consecutive patients with psoriasis were referred from outpatient dermatology practices between January 1, 2013, and October 1, 2017. A total of 138 consecutively recruited patients with psoriasis were followed up at 1 year., Exposures: Circulating soluble lectinlike oxidized low-density lipoprotein receptor-1 levels were measured blindly by field scientists running undiluted serum using an enzyme-linked immunosorbent assay., Main Outcomes and Measures: Coronary computed tomography angiography scans were performed to quantify NCB in all 3 major epicardial coronary arteries by a reader blinded to patient demographics, visit, and treatment status., Results: Among the 175 patients with psoriasis, the mean (SD) age was 49.7 (12.6) years and 91 were men (55%). The cohort had relatively low median cardiovascular risk by Framingham risk score (median, 2.0 [interquartile range (IQR), 1.0-6.0]) and had a mean (SD) body mass index (calculated as weight in kilograms divided by height in meters squared) suggestive of overweight profiles (29.6 [6.0]). Elevated sLOX-1 levels were found in patients with psoriasis compared with age- and sex-matched controls (median, 210.3 [IQR, 110.9-336.2] vs 83.7 [IQR, 40.1-151.0]; P < .001), and were associated with Psoriasis Area Severity Index (PASI) score (β = 0.23; 95% CI, 0.082-0.374; P = .003). Moreover, sLOX-1 was associated with NCB independent of hyperlipidemia status (β = 0.11; 95% CI, 0.016-0.200; P = .023), an association which persisted after adjusting for traditional cardiovascular risk factors, statin use, and biologic psoriasis treatment (β = 0.10; 95% CI, 0.014-0.193; P = .03). At 1 year, in those who had clinical improvement in PASI (eg, >50% improvement), a reduction in sLOX-1 (median, 311.1 [IQR, 160.0-648.8] vs median, 224.2 [IQR, 149.1 - 427.4]; P = .01) was associated with a reduction in NCB (β = 0.14; 95% CI, 0.028-0.246; P = .02)., Conclusions and Relevance: Soluble lectinlike oxidized low-density lipoprotein receptor-1 levels were elevated in patients with psoriasis and were associated with severity of skin disease. Moreover, sLOX-1 associated with NCB independent of hyperlipidemia status, suggesting that inflammatory sLOX-1 induction may modulate lipid-rich NCB in psoriasis. Improvement of skin disease was associated with a reduction of sLOX-1 at 1 year, demonstrating the potential role of sLOX-1 in inflammatory atherogenesis in psoriasis.

Healthy cardiomyocytes are electrically coupled at the intercalated discs by gap junctions. In infarcted hearts, adverse gap-junctional remodeling occurs in the border zone, where cardiomyocytes are chemically and electrically influenced by myofibroblasts. The physical movement of these contacts remains unquantified. Using scanning ion conductance microscopy, we show that intercellular contacts between cardiomyocytes and myofibroblasts are highly dynamic, mainly owing to the edge dynamics (lamellipodia) of the myofibroblasts. Decreasing the amount of functional connexin-43 (Cx43) at the membrane through Cx43 silencing, suppression of Cx43 trafficking, or hypoxia-induced Cx43 internalization attenuates heterocellular contact dynamism. However, we found decreased dynamism and stabilized membrane contacts when cellular coupling was strengthened using 4-phenylbutyrate (4PB). Fluorescent-dye transfer between cells showed that the extent of functional coupling between the 2 cell types correlated with contact dynamism. Intercellular calcein transfer from myofibroblasts to cardiomyocytes is reduced after myofibroblast-specific Cx43 down-regulation. Conversely, 4PB-treated myofibroblasts increased their functional coupling to cardiomyocytes. Consistent with lamellipodia-mediated contacts, latrunculin-B decreases dynamism, lowers physical communication between heterocellular pairs, and reduces Cx43 intensity in contact regions. Our data show that heterocellular cardiomyocyte-myofibroblast contacts exhibit high dynamism. Therefore, Cx43 is a potential target for prevention of aberrant cardiomyocyte coupling and myofibroblast proliferation in the infarct border zone.-Schultz, F., Swiatlowska, P., Alvarez-Laviada, A., Sanchez-Alonso, J. L., Song, Q., de Vries, A. A. F., Pijnappels, D. A., Ongstad, E., Braga, V. M. M., Entcheva, E., Gourdie, R. G., Miragoli, M., Gorelik, J. Cardiomyocyte-myofibroblast contact dynamism is modulated by connexin-43.

Cardiac myocyte-fibroblast electrotonic coupling is a well-established fact in vitro. Indirect evidence of its presence in vivo exists, but few functional studies have been published. This review describes the current knowledge of fibroblast-myocyte electrical signaling in the heart. Further research is needed to understand the frequency and extent of heterocellular interactions in vivo in order to gain a better understanding of their relevance in healthy and diseased myocardium. It is hoped that associated insight into myocyte-fibroblast coupling in the heart may lead to the discovery of novel therapeutic targets and the development of agents for improving outcomes of myocardial scarring and fibrosis., (Copyright © 2016 Elsevier Ltd. All rights reserved.)