TCA cycle metabolites associated with adverse outcomes after acute coronary syndrome: mediating effect of renal function.

Aims: To examine relationships of tricarboxylic acid (TCA) cycle metabolites with risk of cardiovascular events and mortality after acute coronary syndrome (ACS), and evaluate the mediating role of renal function in these associations. Methods: This is a prospective study performed among 309 ACS patients who were followed for a mean of 6.7 years. During this period 131 patients developed major adverse cardiovascular events (MACE), defined as the composite of myocardial infarction, hospitalization for heart failure, and all-cause mortality, and 90 deaths were recorded. Plasma concentrations of citrate, aconitate, isocitrate, succinate, malate, fumarate, α-ketoglutarate and d/l-2-hydroxyglutarate were quantified using LC-tandem MS. Multivariable Cox regression models were used to estimate hazard ratios, and a counterfactual-based mediation analysis was performed to test the mediating role of estimated glomerular filtration rate (eGFR). Results: After adjustment for traditional cardiovascular risk factors and medications, positive associations were found between isocitrate and MACE (HR per 1 SD, 1.25; 95% CI: 1.03, 1.50), and between aconitate, isocitrate, d/l-2-hydroxyglutarate and all-cause mortality (HR per 1 SD, 1.41; 95% CI: 1.07, 1.84; 1.58; 95% CI: 1.23, 2.02; 1.38; 95% CI: 1.14, 1.68). However, these associations were no longer significant after additional adjustment for eGFR. Mediation analyses demonstrated that eGFR is a strong mediator of these associations. Conclusion: These findings underscore the importance of TCA metabolites and renal function as conjunctive targets in the prevention of ACS complications.

Gut Microbiota-Derived Metabolites and Cardiovascular Disease Risk: A Systematic Review of Prospective Cohort Studies.

Gut microbiota-derived metabolites have recently attracted considerable attention due to their role in host-microbial crosstalk and their link with cardiovascular health. The MEDLINE-PubMed and Elsevier's Scopus databases were searched up to June 2022 for studies evaluating the association of baseline circulating levels of trimethylamine N-oxide (TMAO), secondary bile acids, short-chain fatty acids (SCFAs), branched-chain amino acids (BCAAs), tryptophan and indole derivatives, with risk of cardiovascular disease (CVD). A total of twenty-one studies were included in the systematic review after evaluating 1210 non-duplicate records. There were nineteen of the twenty-one studies that were cohort studies and two studies had a nested case-control design. All of the included studies were of high quality according to the "Newcastle-Ottawa Scale". TMAO was positively associated with adverse cardiovascular events and CVD/all-cause mortality in some, but not all of the included studies. Bile acids were associated with atrial fibrillation and CVD/all-cause mortality, but not with CVD. Positive associations were found between BCAAs and CVD, and between indole derivatives and major adverse cardiovascular events, while a negative association was reported between tryptophan and all-cause mortality. No studies examining the relationship between SCFAs and CVD risk were identified. Evidence from prospective studies included in the systematic review supports a role of microbial metabolites in CVD.

The role of serum magnesium and calcium on the association between adiponectin levels and all-cause mortality in end-stage renal disease patients.

BACKGROUND: Adiponectin (ADPN) is the most abundant adipocyte-specific cytokine that plays an important role in energy homeostasis by regulating lipid and glucose metabolism. Studies of the impact of ADPN on clinical outcomes have yielded contradictory results so far. Here, we examined the association of ADPN with serum magnesium (s-Mg) and calcium (s-Ca) levels and explored the possibility whether these two factors could modify the relationship between ADPN and all-cause mortality in patients with end-stage renal disease. METHODOLOGY/PRINCIPAL FINDINGS: After baseline assessment, 47 hemodialysis and 27 peritoneal dialysis patients were followed- up for a median period of 50 months. S-Mg and s-Ca levels emerged as positive and negative predictors of ADPN levels, respectively. During the follow-up period 18 deaths occurred. There was a significant 4% increased risk for all-cause mortality for each 1-µg/ml increment of ADPN (crude HR, 1.04; 95% CI, 1.01-1.07), even after adjustment for s-Mg and s-Ca levels, dialysis mode, age, albumin and C-reactive protein. Cox analysis stratified by s-Mg levels (below and above the median value of 2.45 mg/dl) and s-Ca levels (below and above the median value of 9.3 mg/dl), revealed ADPN as an independent predictor of total mortality only in the low s-Mg and high s-Ca groups. Furthermore, low s-Mg and high s-Ca levels were independently associated with malnutrition, inflammation, arterial stiffening and risk of death. CONCLUSIONS/SIGNIFICANCE: The predictive value of ADPN in all-cause mortality in end-stage renal disease patients appears to be critically dependent on s-Mg and s-Ca levels. Conversely, s-Mg and s-Ca may impact on clinical outcomes by directly modifying the ADPN's bioactivity.

Gluteal adipose-tissue polyunsaturated fatty-acids profiles and depressive symptoms in obese adults with obstructive sleep apnea hypopnea syndrome: a cross-sectional study.

Biomarkers of Polyunsaturated Fatty Acids (PUFAs) have been related to depressive symptoms in healthy adults. It is also known that depression is high prevalent in Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) and obesity. The aim of our study was to examine a possible association between PUFAs of the n-6 and n-3 families and depressive symptoms in obese OSAHS patients. Sixty three patients with OSAHS based on overnight attended polysomnography were included. Gluteal adipose tissue biopsies were performed in all participants. Fatty acids were analyzed by gas chromatography. Depressive symptoms were assessed by the Zung Self-rating Depression Scale. The majority of participants had grade II obesity (BMI: 36.2±4.3 kg/m(2)) and moderate to severe OSAHS. Mild depressive symptoms were found to affect 27.8% of the studied patients. No link between symptoms of depression and individual n-6 and/or n-3 PUFAs of gluteal adipose tissue was detected. However, multiple linear regression analysis showed a positive correlation between depressive symptoms and 20:3n-6/18:3n-6 ratio, and a negative association with age and n-6/n-3 ratio. The possible influence of OSAHS and obesity in depression development and the quiescent nature of gluteal adipose tissue may account for the absence of any significant relations between n-6 and/or n-3 PUFAs and depressive symptoms in our sample. The positive relationship between symptoms of depression and the particular fatty acid ratio probably indicates an increase in prostaglandins family although this needs further research.