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K+ channels play a fundamental role regulating membrane potential of pulmonary artery (PA) smooth muscle cells and their impairment is a common feature in pulmonary arterial hypertension (PAH). K+ voltage-gated channel subfamily Q (KCNQ1-5) or Kv7 channels and their regulatory subunits subfamily E (KCNE) regulatory subunits are known to regulate vascular tone, but whether Kv7 channel function is impaired in PAH and how this can affect the rationale for targeting Kv7 channels in PAH remains unknown. Here, we have studied the role of Kv7/KCNE subunits in rat PA and their possible alteration in PAH. Using the patch-clamp technique, we found that the total K+ current is reduced in PA smooth muscle cells from pulmonary hypertension animals (SU5416 plus hypoxia) and Kv7 currents made a higher contribution to the net K+ current. Likewise, enhanced vascular responses to Kv7 channel modulators were found in pulmonary hypertension rats. Accordingly, KCNE4 subunit was highly upregulated in lungs from pulmonary hypertension animals and patients. Additionally, Kv7 channel activity was enhanced in the presence of Kv1.5 and TASK-1 channel inhibitors and this was associated with an increased KCNE4 membrane abundance. Compared with systemic arteries, PA showed a poor response to Kv7 channel modulators which was associated with reduced expression and membrane abundance of Kv7.4 and KCNE4. Our data indicate that Kv7 channel function is preserved and KCNE4 is upregulated in PAH. Therefore, compared with other downregulated channels, the contribution of Kv7 channels is increased in PAH resulting in an enhanced sensitivity to Kv7 channel modulators. This study provides insight into the potential usefulness of targeting Kv7 channels in PAH.Insulin resistance in the vasculature is a characteristic feature of obesity and contributes to the pathogenesis of vascular dysfunction and disease. selleck kinase inhibitor However, the molecular mechanisms underlying obesity-associated vascular insulin resistance and dysfunction remain poorly understood. We hypothesized that TRAF3IP2 (TRAF3 interacting protein 2), a proinflammatory adaptor molecule known to activate pathological stress pathways and implicated in cardiovascular diseases, plays a causal role in obesity-associated vascular insulin resistance and dysfunction. We tested this hypothesis by employing genetic-manipulation in endothelial cells in vitro, in isolated arteries ex vivo, and diet-induced obesity in a mouse model of TRAF3IP2 ablation in vivo. We show that ectopic expression of TRAF3IP2 blunts insulin signaling in endothelial cells and diminishes endothelium-dependent vasorelaxation in isolated aortic rings. Further, 16 weeks of high fat/high sucrose feeding impaired glucose tolerance, aortic insulin-induced vasorelaxation, and hindlimb postocclusive reactive hyperemia, while increasing blood pressure and arterial stiffness in wild-type male mice. Notably, TRAF3IP2 ablation protected mice from such high fat/high sucrose feeding-induced metabolic and vascular defects. Interestingly, wild-type female mice expressed markedly reduced levels of TRAF3IP2 mRNA independent of diet and were protected against high fat/high sucrose diet-induced vascular dysfunction. These data indicate that TRAF3IP2 plays a causal role in vascular insulin resistance and dysfunction. Specifically, the present findings highlight a sexual dimorphic role of TRAF3IP2 in vascular control and identify it as a promising therapeutic target in vasculometabolic derangements associated with obesity, particularly in males.Oxidative stress and inflammation play key roles in development of pulmonary arterial hypertension (PAH). We previously reported that an endothelial cell (EC)-specific cyclophilin A overexpression mouse developed many characteristics of PAH. In other models of cardiovascular disease, cyclophilin A stimulates smooth muscle proliferation and vascular inflammation, but mechanisms responsible for PAH have not been defined. In particular, the contribution of endothelial-to-mesenchymal transition in cyclophilin A-mediated PAH has not been studied. We identified increased levels of cyclophilin A in endothelial and neointimal cells of pulmonary arteries in patients with PAH and animal pulmonary hypertension models. In the EC-specific cyclophilin A overexpression mouse that exhibited features characteristic of PAH, lineage tracing showed high level expression of mesenchymal markers in pulmonary ECs. A significant number of mesenchymal cells in media and perivascular regions of pulmonary arterioles and alveoli were derived from ECs. Pulmonary ECs isolated from these mice showed phenotypic changes characteristic of endothelial-to-mesenchymal transition in culture. Cultured pulmonary ECs stimulated with extracellular cyclophilin A and acetylated cyclophilin A demonstrated functional changes associated with endothelial-to-mesenchymal transition such as increased cytokine release, migration, proliferation, and mitochondrial dysfunction. Acetylated cyclophilin A stimulated greater increases for most features of endothelial-to-mesenchymal transition. In conclusion, extracellular cyclophilin A (especially acetylated form) contributes to PAH by mechanisms involving increased endothelial-to-mesenchymal transition, cytokine release, EC migration, proliferation, and mitochondrial dysfunction; strengthening the basis for studying cyclophilin A inhibition as a therapy for PAH.Casein hydrolysate has been shown to improve arterial stiffness as estimated by brachial-ankle pulse wave velocity (baPWV) in untreated hypertensive patients. Facial pigmentation is associated with atherosclerosis, both of which are supposed to be modulated by tissue accumulation of advanced glycation end products (AGEs). However, effects of casein hydrolysate on facial pigmentation and AGEs remain largely unknown. This randomized double-blind placebo-controlled trial evaluated whether and how casein hydrolysate improves facial pigmentation in 80 nonhypertensive Japanese patients. Study participants were randomly assigned to receive either active tablets containing casein hydrolysate or placebo for 48 weeks. Facial pigmentation area, baPWV, and skin accumulation levels of AGEs were evaluated by Robo Skin Analyzer RSA50S II, volume-plethysmographic apparatus, and AGE Reader, respectively, at baseline and at the end of the intervention. Treatment with casein hydrolysate, but not placebo significantly reduced triglycerides and facial pigmentation area.

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