RESUMEN
Heart failure (HF) is characterized by low-grade immune-mediated inflammation due to increased Toll-like receptor (TLR) expression as response to endotoxin increase and dysregulated gut barrier permeability. We investigated TLR expression and possible gut dysbiosis in HF patients compared to a control group. We enrolled 80 Caucasian HF patients and 20 controls. Low-grade immune-mediated inflammation was evaluated by TLR expression, while gut dysbiosis by the detection of zonulin and bacterial endotoxin activity in a semi-quantitative (endotoxin activity assay [EAA]) and quantitative (limulus amebocyte lysate [LAL] test) way. Compared to controls, patients with HF showed significantly higher age and blood pressure values, worse metabolic profile and kidney function, higher inflammatory biomarkers levels, and lower levels of zonulin and endotoxin activity. When dividing failing patients in those with reduced ejection fraction (HF-rEF) and those with preserved ejection fraction (HF-pEF), HF-rEF patients showed significantly higher values of inflammatory biomarkers and TLR expression than HF-pEF patients. Gut permeability biomarkers inversely correlated with the severity of HF and positively with renal function. eGFR was retained as an independent predictor of zonulin variation in all the three groups of failing patients. Present data work to extend current knowledge about the role of gut microbiota in immune-mediated inflammation in HF.
RESUMEN
BACKGROUND AND AIMS: Our prior study showed that endothelial dysfunction contributed to reduced myocardial mechano-energetics efficiency (MEEi) independently of several confounders. Reduced activity of endothelial nitric oxide synthase may be due to increased levels of the endogenous inhibitor asymmetric dimethylarginine (ADMA). The impact of ADMA on myocardial MEEi has not been determined yet. This study aims to investigate the association between plasma ADMA levels and MEEi in drug-naïve hypertensive individuals. METHODS AND RESULTS: 63 hypertensive individuals participating in the CATAnzaro MEtabolic RIsk factors (CATAMERI) study were included. All participants underwent to an echocardiogram for myocardial MEEi measurement. ADMA plasma concentrations were measured by high-performance liquid chromatography. A multivariate linear regression analysis was conducted to investigate the independent association between ADMA levels and MEEi. In a univariate analysis, ADMA levels were significantly associated with myocardial MEEi (r = 0.438; P < 0.001). In a multivariate regression analysis, plasma ADMA levels were associated to decreased myocardial MEEi (ß = 0.458, P < 0.001) independently of well-established cardiovascular risk factors including age, sex, BMI, waist circumference, smoking status, total cholesterol and HDL, triglycerides, glucose tolerance status, and HOMA-IR index of insulin resistance. CONCLUSIONS: ADMA may contribute to reduced myocardial MEEi by reducing nitric oxide bioavailability.