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Background: Normal endothelial cell dependent vascular smooth muscle cell function is mediated by nitric oxide (NO), which stimulates soluble guanylyl cyclase (sGC) production of the second messenger, cyclic guanosine monophosphate (cGMP) leading to increased protein kinase G (PKG) activity and vascular smooth muscle relaxation. NO bioavailability is impaired in inflammatory settings, such as high glucose (HG). We examined whether the direct sGC sensitizer/stimulator vericiguat, augments cGMP production in human vascular smooth muscle cells (HVSMC) exposed to high glucose and explored its effect on vasorelaxation. Methods: Aortic HVSMCs were exposed to HG for 24h. In the treatment group, cells also received 1uM vericiguat for 24h. After incubation, cGMP and PKG activity were measured. Additionally, thoracic murine aortas were exposed to HG or to normal glucose (NG) control. The rings were then placed in an organ chamber bath and dose response curves to increasing doses of acetylcholine (Ach) and sodium nitroprusside were constructed for three groups: control (normal glucose), HG alone, and HG + vericiguat. Results: HVSMCs exposed to HG produced significantly less cGMP than those exposed to NG. cGMP production in the presence of HG was rescued when treated with 1uM vericiguat. Additionally, PKG activity was impaired in the presence of HG and enzyme activity was restored with vericiguat. In isolated mouse aortic rings, ACh mediated relaxation was impaired following treatment with HG, but was improved when a HG group was treated with vericiguat. Conclusions: The sGC sensitizer/stimulator vericiguat restored cGMP production and PKG activity in the setting of HG. Vericiguat enhanced ACh-mediated vasorelaxation in the setting of HG. The findings suggest clinical studies are warranted to investigate the potential of sGC sensitization/stimulation as a therapeutic intervention to improve vascular endothelial-dependent function that is impaired in pro-inflammatory settings that are associated with the development of atherosclerotic disease.
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BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have emerged as a novel class of drugs with cardioprotective effects through their lipid-lowering effects. OBJECTIVE: This review aims to discuss existing and novel strategies of PCSK9 inhibition, providing an overview of established randomized controlled trials and ongoing outcome trials that assess the efficacy and long-term safety of PCSK9 inhibitors. It also explores the evolving role of PCSK9 beyond lipid metabolism and outlines the pleiotropic actions of PCSK9 inhibition in various disorders and future directions including novel strategies to target PCSK9. CONCLUSION: PCSK9 inhibition shows promise not only in lipid metabolism but also in other disease processes, including atherosclerotic plaque remodeling, acute coronary syndrome, stroke, inflammation, and immune response.
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BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is primarily recognized for its role in lipid metabolism, but recent evidence suggests that it may have broader implications due to its diverse tissue expression. OBJECTIVE: This review aims to explore the multifaceted functions of PCSK9, highlighting its pro-atherosclerotic effects, including its impact on circulating lipoprotein variables, non-low-density lipoprotein receptors, and various cell types involved in atherosclerotic plaque development. CONCLUSIONS: PCSK9 exhibits diverse roles beyond lipid metabolism, potentially contributing to atherosclerosis through multiple pathways. Understanding these mechanisms could offer new insights into therapeutic strategies targeting PCSK9 for cardiovascular disease management.
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Aging is associated with a significant decline in aerobic capacity assessed by maximal exercise oxygen consumption (VÌo2max). The relative contributions of the specific VÌo2 components driving this decline, namely cardiac output (CO) and arteriovenous oxygen difference (A - V)O2, remain unclear. We examined this issue by analyzing data from 99 community-dwelling participants (baseline age: 21-96 yr old; average follow-up: 12.6 yr old) from the Baltimore Longitudinal Study of Aging, free of clinical cardiovascular disease. VÌo2peak, a surrogate of VÌo2max, was used to assess aerobic capacity during upright cycle ergometry. Peak exercise left ventricular volumes, heart rate, and CO were estimated using repeated gated cardiac blood pool scans. The Fick equation was used to calculate (A - V)O2diff,peak from COpeak and VÌo2peak. In unadjusted models, VÌo2peak, (A - V)O2diff,peak, and COpeak declined longitudinally over time at steady rates with advancing age. In multiple linear regression models adjusting for baseline values and peak workload, however, steeper declines in VÌo2peak and (A - V)O2diff,peak were observed with advanced entry age but not in COpeak. The association between the declines in VÌo2peak and (A - V)O2diff,peak was stronger among those ≥50 yr old compared with their younger counterparts, but the difference between the two age groups did not reach statistical significance. These findings suggest that age-associated impairment of peripheral oxygen utilization during maximal exercise poses a stronger limitation on peak VÌo2 than that of CO. Future studies examining interventions targeting the structure and function of peripheral muscles and their vasculature to mitigate age-associated declines in (A - V)O2diff are warranted.NEW & NOTEWORTHY The age-associated decline in aerobic exercise performance over an average of 13 yr in community-dwelling healthy individuals is more closely associated with decreased peripheral oxygen utilization rather than decreased cardiac output. This association was more evident in older than younger individuals. These findings suggest that future studies with larger samples examine whether these associations vary across the age range and whether the decline in cardiac output plays a greater role earlier in life. In addition, studies focused on determinants of peripheral oxygen uptake by exercising muscle may guide the selection of preventive strategies designed to maintain physical fitness with advancing age.
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Envelhecimento , Débito Cardíaco , Consumo de Oxigênio , Humanos , Idoso , Pessoa de Meia-Idade , Masculino , Consumo de Oxigênio/fisiologia , Feminino , Adulto , Envelhecimento/fisiologia , Envelhecimento/metabolismo , Estudos Longitudinais , Idoso de 80 Anos ou mais , Adulto Jovem , Baltimore , Fatores Etários , Tolerância ao Exercício , Teste de EsforçoRESUMO
BACKGROUND: It is unclear how metabolic syndrome (MetS) and diabetes affect Gal-3 (galectin 3) levels and the resulting implications for heart failure (HF) risk. We assessed relationships of MetS and diabetes with Gal-3, and their joint associations with incident HF. METHODS AND RESULTS: We included 8445 participants without HF (mean age, 63 years; 59% men; 16% Black race) at ARIC (Atherosclerosis Risk in Communities) study visit 4 (1996-1999). We categorized participants as having MetS only, MetS with diabetes, or neither, and by quartiles of MetS severity Z score. We assessed cross-sectional associations of metabolic risk categories with high Gal-3 level (≥75th percentile) using logistic regression. We used Cox regression to evaluate combined associations of metabolic risk categories and Gal-3 quartiles with HF. In cross-sectional analyses, compared with no MetS and no diabetes, MetS only (odds ratio [OR], 1.24 [95% CI, 1.10-1.41]) and MetS with diabetes (OR, 1.59 [95% CI, 1.32-1.92]) were associated with elevated Gal-3. Over a median follow-up of 20.5 years, there were 1749 HF events. Compared with individuals with neither diabetes nor MetS and with Gal-3 in the lowest quartile, the combination of MetS with diabetes and Gal-3 ≥75th percentile was associated with a 4-fold higher HF risk (hazard ratio, 4.35 [95% CI, 3.30-5.73]). Gal-3 provided HF prognostic information above and beyond MetS, NT-proBNP (N-terminal pro-B-type natriuretic peptide), high-sensitivity cardiac troponin T, and CRP (C-reactive protein) (ΔC statistic for models with versus without Gal-3: 0.003; P=0.004). CONCLUSIONS: MetS and diabetes are associated with elevated Gal-3. The HF risk significantly increased with the combination of greater metabolic risk and higher Gal-3.
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Diabetes Mellitus , Insuficiência Cardíaca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores , Estudos Transversais , Galectina 3 , Insuficiência Cardíaca/epidemiologia , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Fatores de RiscoRESUMO
BACKGROUND AND AIMS: People with HIV (PWH) whose disease is controlled on anti-retroviral regimens remain at an increased risk for coronary artery disease (CAD). Traditional cardiovascular risk factors do not fully explain the residual risk in PWH suggesting contributions from nontraditional factors. Homocysteine (Hcy) may be one of these as prior work in adults without HIV demonstrate that Hcy may impair endothelial function by decreasing the availability of nitric oxide, promoting the development of atherosclerosis. In addition, plasma Hcy levels are higher in PWH than in individuals living without HIV. The aim of this study was to investigate whether Hcy levels influence the association between HIV and coronary stenosis in an inner city African American population. METHODS: African Americans from the Heart Study in Baltimore, with and without HIV, recruited from inner-city Baltimore between June 2004 and February 2015, were included in this analysis. Participants underwent coronary CT angiography to evaluate the presence of coronary stenosis, defined as luminal stenosis >10%. Hcy was measured from stored serum samples. RESULTS: In this analysis, the median [IQR] age of the 664 participants was 56 [50-66] years; 68.1% were living with HIV and 43.1% were women. Elevated Hcy (>15 µmol/L) was more prevalent in those with coronary stenosis (23.3%, 95% CI: 18.4%-28.2%) than in those without coronary stenosis (13.1%, 95% CI: 9.7%-16.5%) (p = 0.0007), and HIV was associated with coronary stenosis in those participants with an elevated Hcy (Prevalence Ratio: 1.94, 95% CI: 1.04-3.64, p = 0.0038) and not in those with a Hcy ≤15 µmol/L (Prevalence Ratio: 1.02, 95% CI: 0.83-1.25, p = 0.87). CONCLUSIONS: Our data suggest an association between elevated Hcy levels (>15 µmol/L) and the prevalence of coronary stenosis in PWH from this inner city African American population.
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Negro ou Afro-Americano , Estenose Coronária , Infecções por HIV , Homocisteína , Humanos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Homocisteína/sangue , Estenose Coronária/epidemiologia , Estenose Coronária/sangue , Negro ou Afro-Americano/estatística & dados numéricos , Baltimore/epidemiologia , Idoso , Fatores de Risco , Angiografia Coronária , População Urbana/estatística & dados numéricosRESUMO
As the older adult population expands, an increasing number of patients affected by geriatric syndromes are seen by cardiovascular clinicians. One such syndrome that has been associated with poor outcomes is cognitive frailty: the simultaneous presence of cognitive impairment, without evidence of dementia, and physical frailty, which results in decreased cognitive reserve. Driven by common pathophysiologic underpinnings (eg, inflammation and neurohormonal dysregulation), cardiovascular disease, cognitive impairment, and frailty also share the following risk factors: hypertension, diabetes, obesity, sedentary behavior, and tobacco use. Cardiovascular disease has been associated with the onset and progression of cognitive frailty, which may be reversible in early stages, making it essential for clinicians to diagnose the condition in a timely manner and prescribe appropriate interventions. Additional research is required to elucidate the mechanisms underlying the development of cognitive frailty, establish preventive and therapeutic strategies to address the needs of older patients with cardiovascular disease at risk for cognitive frailty, and ultimately facilitate targeted intervention studies.
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Doenças Cardiovasculares , Disfunção Cognitiva , Diabetes Mellitus , Fragilidade , Humanos , Idoso , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Cognição/fisiologia , Avaliação Geriátrica/métodosRESUMO
OBJECTIVE: To evaluate the performance of the turbidimetric method of C-reactive protein (CRP) as a measure of low-grade inflammation in patients admitted with non-ST elevation acute coronary syndromes (ACS). METHODS: Serum samples obtained at hospital arrival from 68 patients (66±11 years, 40 men), admitted with unstable angina or non-ST elevation acute myocardial infarction were used to measure CRP by the methods of nephelometry and turbidimetry. RESULTS: The medians of C-reactive protein by the turbidimetric and nephelometric methods were 0.5 mg/dL and 0.47 mg/dL, respectively. A strong linear association existed between the 2 methods, according to the regression coefficient (b=0.75; 95 percent C.I.=0.70-0.80) and correlation coefficient (r=0.96; P<0.001). The mean difference between the nephelometric and turbidimetric CRP was 0.02 ± 0.91 mg/dL, and 100 percent agreement between the methods in the detection of high CRP was observed. CONCLUSION: In patients with non-ST elevation ACS, CRP values obtained by turbidimetry show a strong linear association with the method of nephelometry and perfect agreement in the detection of high CRP