lncR-GAS5 upregulates the splicing factor SRSF10 to impair endothelial autophagy,leading to atherogenesis

Long noncoding RNAs(lncRNAs)play a critical role in the regulation of atherosclerosis.Here,we investigated the role of the lncRNA growth arrest-specific 5(lncR-GAS5)in atherogenesis.We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis,which presented as increased plaque size and reduced collagen content.Moreover,impaired autophagy was observed,as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells.By contrast,lncR-GAS5 knockdown promoted autophagy.Moreover,serine/arginine-rich splicing factor 10(SRSF10)knockdown increased the LC3II/LC3I ratio and decreased the P62 level,thus enhancing the formation of autophagic vacuoles,autolysosomes,and autophagosomes.Mechanistically,lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium,which was reversed by the knockdown of SRSF10.Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene,SRSF10.Notably,miR-193-5p overexpression decreased plaque size and increased collagen content.Altogether,these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy.In conclusion,lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway.Thus,miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

Antioxidants,inflammation and cardiovascular disease

Multiple factors are involved in the etiology of cardiovascular disease(CVD). Pathological changes occur in a variety of cell types long before symptoms become apparent and diagnosis is made. Dysregulation of physiological functions are associated with the activation of immune cells,leading to local and finally systemic inflammation that is characterized by production of high levels of reactive oxygen species(ROS). Patients suffering from inflammatory diseases often present with diminished levels of antioxidants either due to insufficient dietary intake or,and even more likely,due to increased demand in situations of overwhelming ROS production by activated immune effector cells like macrophages. Antioxidants are suggested to beneficially interfere with diseases-related oxidative stress,however the interplay of endogenous and exogenous antioxidants with the overall redox system is complex. Moreover,molecular mechanisms underlying oxidative stress in CVD are not fully elucidated. Metabolic dybalances are suggested to play a major role in disease onset and progression. Several central signalingpathways involved in the regulation of immunological,metabolic and endothelial function are regulated in a redox-sensitive manner. During cellular immune response,interferon γ-dependent pathways are activated such as tryptophan breakdown by the enzyme indoleamine 2,3-dioxygenase(IDO) in monocyte-derived macrophages,fibroblasts,endothelial and epithelial cells. Neopterin,a marker of oxidative stress and immune activation is produced by GTP-cyclohydrolase Ⅰ in macrophages and dendritic cells. Nitric oxide synthase(NOS) is induced in several cell types to generate nitric oxide(NO). NO,despite its low reactivity,is a potent antioxidant involved in the regulation of the vasomotor tone and of immunomodulatory signaling pathways. NO inhibits the expression and function of IDO. Function of NOS requires the cofactor tetrahydrobiopterin(BH4),which is produced in humans primarily by fibroblasts and endothelial cells. Highly toxic peroxynitrite(ONOO-) is formed solely in the presence of superoxide anion(O2-). Neopterin and kynurenine to tryptophan ratio(Kyn/Trp),as an estimate of IDO enzyme activity,are robust markers of immune activation in vitro and in vivo. Both these diagnostic parameters are able to predict cardiovascular and overall mortality in patients at risk. Likewise,a significant association exists between increase of neopterin concentrations and Kyn/Trp ratio values and the lowering of plasma levels of vitamin-C,-E and-B. Vitamin-B deficiency is usually accompanied by increased plasma homoycsteine. Additional determination of NO metabolites,BH4 and plasma antioxidants in patients with CVD and related clinical settings can be helpful to improve the understanding of redox-regulation in health and disease and might provide a rationale for potential antioxidant therapies in CVD.

Practical strategies for modulating foam cell formation and behavior

Although high density lipoprotein(HDL)-mediated reverse cholesterol transport is crucial to the prevention and reversal of atheroma, a recent meta-analysis makes evident that current pharmaceutical strategies for modulating HDL cholesterol levels lower cardiovascular risk only to the extent that they concurrently decrease low density lipoprotein(LDL) cholesterol. This corresponds well with findings of a recent Mendelian randomization analysis, in which genetic polymorphisms associated with HDL cholesterol but no other known cardiovascular risk factors failed to predict risk for myocardial infarction. Although it is still seems appropriate to search for therapies that could improve the efficiency with which HDL particles induce reverse cholesterol transport, targeting HDL cholesterol levels per se with current measures appears to be futile. Itmay therefore be more promising to promote reverse cholesterol transport with agents that directly target foam cells. Macrophage expression of the cholesterol transport proteins adenosine triphosphate binding cassette transporter A1, adenosine triphosphate binding cassette transporter G1, and scavenger receptor class B member 1 is transcriptionally up-regulated by activated liver X receptors(LXR), whereas nuclear factor(NF)-kappa B antagonizes their expression. Taurine, which inhibits atherogenesis in rodent studies, has just been discovered to act as a weak agonist for LXRalpha. Conversely, it may be possible to oppose NF-kappa B activation in macrophages with a range of measures. Induction of heme oxygenase-1, which can be attained with phase 2 inducer phytochemicals such as lipoic acid and green tea catechins, promotes reverse cholesterol transport in macrophages and inhibits atherogenesis in rodents, likely due to, in large part, NF-kappa B antagonism. Inhibition of macrophage nicotinamide adenine dinucleotide phosphate(NADPH) oxidase activity with the spirulina-derived bilirubin-mimetic phycocyanobilin may also oppose NF-kappa B activation, and salicylic acid similarly should be useful for this purpose. The 5' adenosine monophosphate-activated protein kinase activator berberine promotes macrophage reverse cholesterol transport in cell culture; metformin probably shares this property. Many of these measures could also be expected to promote plaque stability by suppressing foam cell production of inflammatory cytokines and matrix metalloproteinases, and to reduce intimal monocyte infiltration by anti-inflammatory effects on vascular endothelium. Direct targeting of foam cells with agents such as phase 2 inducers, spirulina, salicylate, taurine, and berberine or metformin, may hence have considerable potential for preventing and reversing atheroma, and for preventing the plaque rupture that triggers vascular thrombosis.

CARMA3: A novel scaffold protein in regulation of NF-κB activation and diseases

CARD recruited membrane associated protein 3 (CARMA3) is a novel scaffold protein. It belongs to the CARMA protein family, and is known to activate nuclear factor (NF)- κB. However, it is still unknown which receptor functions upstream of CARMA3 to trigger NF-κB activation. Recently, several studies have demonstrated that CARMA3 serves as an indispensable adaptor protein in NF-κB signaling under some G protein-coupled receptors (GP- CRs), such as lysophosphatidic acid (LPA) receptor and angiotensin (Ang) Ⅱ receptor. Mechanistically, CARMA3 recruits its essential downstream molecules Bcl10 and MALT1 to form the CBM (CARMA3-Bcl10-MALT1) signalosome whereby it triggers NF-κB activation. GPCRs and NF-κB play pivotal roles in the regulation of various cellular functions, therefore, aberrant regulation of the GPCR/NF-κB signaling axis leads to the development of many types of diseases, such as cancer and atherogenesis. Recently, the GPCR/CARMA3/NF-κB signaling axis has been confirmed in these specific diseases and it plays crucial roles in the pathogenesis of disease progression. In ovarian cancer cell lines, knockdown of CARMA3 abolishes LPA receptor-induced NF-κB activation, and reduces LPA-induced ovarian cancer invasion. In vascular smooth cells, downregulation of CARMA3 substantially impairs Ang-Ⅱ-receptor-induced NF-κB activation, and in vivo studies have confirmed that Bcl10- deficient mice are protected from developing Ang-Ⅱ-receptor-induced atherosclerosis and aortic aneurysms. In this review, we summarize the biology of CARMA3, describe the role of the GPCR/CARMA3/NF-κB signaling axis in ovarian cancer and atherogenesis, and speculate about the potential roles of this signaling axis in other types of cancer and diseases. With a significant increase in the identification of LPA- and Ang-Ⅱ-like ligands, such as endothelin-1, which also activates NF-κB via CARMA3 and contributes to the development of many diseases, CARMA3 is emerging as a novel therapeutic target for various types of cancer and other diseases.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising.Diabetes mellitus by itself is linked to adverse cardiovascular events,and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk.The culmination of traditional(male gender,smoking,advanced age,obesity,arterial hypertension and dyslipidemia)and non-traditional risk factors(anemia,inflammation,proteinuria,volume overload,mineral metabolism abnormalities,oxidative stress,etc.)contributes to advanced atherosclerosis and increased cardiovascular risk.To decrease the morbidity and mortality of these patients due to cardiovascular causes,timely and efficient cardiovascular risk assessment is of huge importance.Cardiovascular risk assessment can be based on laboratory parameters,imaging techniques,arterial stiffness parameters,ankle-brachial index and 24 h blood pressure measurements.Newer methods include epigenetic markers,soluble adhesion molecules,cytokines and markers of oxidative stress.In this review,the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Catechins Green Tea GMB4 Clone Increases mRNA of ABCA1 through LXR Signaling in Cultured Macrophage Exposed OX-LDL

Inhibition of atherogenesis through inhibition of lipid metabolism has not been explored while other inhibitions through inflammation, endothelial dysfunction and free radicals have done. Inhibition of atherogenesis via inhibition of lipid metabolism can be done through the mechanism of Reverse Cholesterol Transport (RCT). Signaling pathways that play a role in this mechanism is LXR signaling. LXR activation by an LXR agonist led increasing cholesterol efflux. Catechins based on bioinformatics study showed as a potent candidate LXR agonists that can be used as an inhibitor of atherogenesis. This study aims to prove that the administration Catechins green tea Clone GMB4 can prevent atherosclerosis through increasing mechanism cholesterol efflux from macrophage by taking effect of ABCA1, ABCG1, SRB1 gene expression in cultured macrophages were exposed ox-LDL. Long-term goals of the outcome of the research are the use of Catechins Green Tea Clones GMB4 as an inhibitor of atherogenesis so that it can be used as a complementary therapy for the treatment of atherosclerosis and cardiovascular diseases. The research is divided into 5 groups, namely the culture of macrophages without exposed ox-LDL, culture exposed ox-LDL and groups of Catechins dose I, II, III. In vitro study showed that administration of Catechins increases mRNA of ABCA1, whereas mRNA ABCG1 and SRB1 decreased at all three doses given. The result of protein profilling was identified a protein with a molecular weight of 70 kDa by SDS-PGE with silver staining.

Elevated Plasma Levels but Decreased Platelet-Associated Expression of LIGHT in Patients with Acute Atherothrombotic Stroke

Background: As a member of the tumor necrosis factor superfamily (TNFSF), LIGHT (TNFSF14) is expressed by a variety of immune cells and exists in membrane-bound and soluble forms. Recently, LIGHT was found to be associated with platelets and released upon activation. Activation of endothelia cells by recombinant LIGHT protein results in pro-inflammatory and pro-thrombotic changes. Several studies have reported increased plasma levels of LIGHT in patients with stroke and cardiovascular diseases. However, the form-associated roles of LIGHT in ischemic atherosclerotic stroke remain unclear. Mater?als and Methods: In this study, the platelet LIGHT expression and soluble LIGHT protein were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA) in peripheral blood of patients with acute ischemic atherosclerotic stroke, asymptomatic carotid stenosis (ACS) and normal controls. RESULTS: During the initial 24 h after onset, the stroke patients had decreased LIGHT expression on their platelets (5.9% ± 4.9%) and increased plasma LIGHT levels (36.1 ± 21.0 pg/ml) as compared with normal controls (9.5% ± 3.0%, p p < 0.05). Moreover, the platelet LIGHT expression correlated with total plaque area in the stroke patients (r = 0.4572, p = 0.0247). Conclus?ons: The dysregulated LIGHT expression reflects a persistent chronic inflammatory response that may have been induced during early stages of ischemic atherosclerotic stroke. Our results strongly suggest distinctive roles of form-associated LIGHT in the disease pathogenesis: platelet-associated LIGHT may contribute to formation and development of carotid atherosclerotic plaque, probably involving plaque destabilization, while soluble LIGHT may predominantly functions as a pro-inflammatory cytokine in the inflammatory process.

Before the Jury Is out on Cinacalcet’s Cardiovascular Effects in Hemodialysis Patients: Is Troponin a Missing Link?

Raised levels of the cardiac biomarker, Troponin I, are frequently encountered in hemodialysis patients and appear to be prognostic indicators for cardiovascular risk. Though evidence suggests that control of secondary hyperparathyroidism may reduce cardiac endpoints, the effect of the calcimimetic agent, cinacalcet, remains controversial. This retrospective study aimed at evaluating troponin levels in hemodialysis patients with severe secondary hyper parathyroidism (SHPT) who are on cinacalcet vs controls on conventional treatment. In addition, clinical outcomes including all-cause, cardiovascular morbidity and mortality were compared among both groups. A decline in Troponin I levels was observed in the cinacalcet group, this however was not translated clinically into improved survival. In fact, all-cause and cardiac mortality was similar in the two groups. Conversely, comparison of the incidence of cardiovascular events revealed lower rates in the cinacalcet group including cardiac, cerebral and peripheral vascular complications. Given some of our study limitations, further long-term, placebo-controlled trials are necessary to definitively establish the effect of cinacalet on cardiac biomarkers and ultimately its impact on clinical outcomes.

Atherogenic Diet Accelerates Ectopic Mineralization in a Mouse Model of Pseudoxanthoma Elasticum

Objective:Pseudoxanthoma elasticum(PXE)is a multisystem heritable disorder caused by mutations in the Abcc6 gene.The disease is characterized by ectopic mineralization of the skin,eyes,and arterial blood vessels.Previous studies have suggested that cardiovascular complications in patients with PXE are caused in part by premature atherosclerosis.The aim of this study is to determine the effect of an atherogenic diet on ectopic mineralization.Methods:We used Abcc6^(tm1JfK)mice(Abcc6^(-/-)mice)as an established preclinical model of PXE.The offspring at age of 4 weeks were divided into two groups and fed the standard control laboratory diet(control group)and the atherogenic diet.Serum lipid profiles and bile acids were measured,and steatosis and tissue mineralization were evaluated by histopathologic analysis and chemical calcium quantification assay,respectively.Results:After 50-58 weeks of feeding an atherogenic diet,the concentrations of total cholesterol,low-density lipoprotein/very-low-density lipoprotein cholesterol,and bile acids were significantly higher in the Abcc6^(-/-)mice on the atherogenic diet(180.9±14.8 g/L,145.9±12.9 g/L,and 9.7±1.4μmol/L,respectively)than in Abcc6^(-/-)mice on a control diet(85.2±4.8 g/L,25.1±5.5 g/L,and 3.3±0.5μmol/L,respectively)(P<0.001).Hypercholesterolemia was accompanied by extensive lipid accumulation in the liver and aorta,a characteristic feature of steatosis.The direct calcium assay demonstrated significantly increased mineralization of the muzzle skin containing the dermal sheath of vibrissae(57.2±4.4μmol Ca/gram tissue on the atherogenic diet and 43.9±2.2μmol Ca/gram tissue on control diet;P<0.01),a reproducible biomarker of the ectopic mineralization process in these mice.An increased frequency of mineralization was also observed in the kidneys and eyes of mice on the atherogenic diet(P<0.01).Conclusion:These observations suggest that the atherogenic diet caused hypercholesterolemia and accelerated ectopic mineralization in the Abcc6^(-/-)mice.Our findings have clinical implications for patients with PXE,a currently intractable disorder with considerable morbidity and occasional mortality.

Advances in research of Apo C-Ⅲ and Coronary Atherosclerosis Heart Disease

Coronary atherosclerotic heart disease had been regarded as the leading killer of human being.The atherosclerotic lesion would cause blood flow blockage or lumen stenosis of coronary arteries,thus resulting in myocardial ischemic or sudden cardiac death.Though exact causes of coronary atherosclerosis heart disease is not known,the promising Apo C-Ⅲthat played a crucial role in metabolism of triglyceride-rich lipoproteins had been supposed to be one of the key factor of pathogenesis.In this review,we discuss roles of Apo C-Ⅲin the development of CAD and its insights being a new therapeutic target.