Objectives. Recent metabolomic, experimental and clinical studies have demonstrated that trimethylamine-N-oxide (TMAO), a microbiotadependent metabolite from dietary phosphatidylcholine and carnitine, is a strong predictor of coronary artery disease (CAD). This finding suggests a link between the gut microbiota and atherosclerosis. The potential impact of TMAO in chronic heart failure (HF) is unknown. We hypothesized that TMAO levels would provide prognostic information about adverse outcomes in chronic HF.Design. Prospective, observational study including 155 consecutive patients with chronic HF. In addition, 100 patients with stable CAD without HF and 33 matched healthy individuals were included as controls. Plasma levels of TMAO and its precursors choline and betaine were measured, and associations with symptoms, aetiology and transplant-free survival in the patients with HF were explored.Results. Plasma levels of TMAO (P = 0.01), choline (P < 0.001) and betaine (P < 0.001) were elevated in patients with chronic HF compared to control subjects, with the highest levels in patients with New York Heart Association (NYHA) classes III and IV. Furthermore, TMAO levels were highest in individuals with ischaemic HF, followed by those with stable CAD and nonischaemic HF. TMAO, but not choline or betaine, was associated with reduced transplant-free survival: approximately 50% of patients in the upper tertile of TMAO levels died or received a heart transplant during 5.2 years of follow-up (unadjusted Cox-regression: hazard ratio 2.24, 95% confidence interval 1.28-3.92, P = 0.005).Conclusions. TMAO levels were elevated in patients with HF and associated with NYHA class, ischaemic aetiology and adverse outcomes. Future studies should focus on gut microbiota, dietary composition and intestinal dysfunction in relation to TMAO levels and clinical outcome in HF.

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Reduced, oxidized and protein-bound forms of homocysteine (Hcy), cysteine and cysteinylglycine in plasma interact via redox and disulphide exchange reactions, and these aminothiol species comprise a dynamic system referred to as redox thiol status. Notably, in plasma reduced cysteine is the most abundant low molecular weight sulfhydryl compound. Elevation of plasma Hcy (hyperhomocysteinemia) causes changes in redox thiol status. Protein-bound Hcy increases up to a maximum capacity of about 140 micromol/L, and there is a concurrent displacement of protein-bound cysteine. When the Hcy binding approaches saturation, free oxidized and reduced Hcy show a substantial increase. The resulting increase in reduced/total ratio for Hcy causes a parallel change in this ratio for the other aminothiols. These dynamics were observed during both chronic hyperhomocysteinemia (due to cobalamin deficiency or homocystinuria) and acute hyperhomocysteinemia (induced by methionine or Hcy loading). In addition, changes in redox thiol status have been observed in patients with vascular disease (decreased reduced/total ratio for cysteine), renal failure (low reduced/total ratio for aminothiols) or HIV infection (high level of reduced Hcy), which suggest primary imbalance between prooxidant and antioxidant processes in these patients. In conclusion, redox thiol status is a dynamic system which is probably linked to the extracellular antioxidant defence system. This must be taken into account when designing future experimental or epidemiological studies on Hcy and cardiovascular disease.

Elevated total homocysteine (Hcy) in plasma is an independent risk factor for early-onset vascular disease in the coronary, cerebral, and peripheral arteries. Different forms of Hcy, and their relation to other aminothiols in plasma, have not been investigated in patients with vascular disease. We therefore investigated 65 patients (35 men and 30 women) operated on for peripheral arterial disease at < 50 years of age and 65 age- and sex-matched control subjects. Total, reduced, oxidized, and protein-bound Hcy, cysteine (Cys), and cysteinylglycine (CysGly) were measured 0 to 11 years (mean, 6 years) postoperatively, in the fasting state, and after a standard methionine loading dose that caused a transient increase in reduced, oxidized, and protein-bound Hcy. All forms of Hcy and Cys, except reduced Cys, were higher in fasting patients than fasting control subjects. A similar difference between the groups was observed after methionine loading. The levels of most Hcy forms both during fasting and after methionine loading were related to smoking, but multivariate analysis showed that the difference between patients and control subjects could not be explained by smoking alone. Notably, reduced Cys and the reduced/total ratio for Cys were significantly higher in control subjects than in patients, both during fasting and after methionine loading. In both groups, the redox status and protein binding of the various aminothiols in plasma were interactive, as demonstrated by positive correlations between their reduced/total ratios and by a decrease in protein-bound Cys when protein-bound Hcy was elevated during methionine loading.(ABSTRACT TRUNCATED AT 250 WORDS)

Patients with carotid atherosclerosis had increased serum levels of γBB, and elevated levels of γBB and its precursor TML were associated with cardiovascular mortality. Long-term clinical studies of γBB, as a cardiovascular risk marker, and safety studies regarding dietary supplementation of γBB, are warranted.

Our findings demonstrate that FO and KO are comparable dietary sources of n-3 PUFAs. However, when quantitatively similar doses of n-3 PUFAs are administered, KO seems to have a greater potential to promote lipid catabolism. The effect of dietary oils on the levels of inflammatory markers in hTNF-α transgenic mice fed a high-fat diet needs further investigations.

Treatment of iron deficiency with ferrous fumarate deteriorated plasma antioxidant status and increased specific clinical symptoms in patients with active Crohn disease. Plasma reduced cysteine may be a sensitive indicator for oxidative stress in the intestine.

A considerable subgroup of CVI patients appears to be characterized by low vitamin A levels. Our findings support a possible role for vitamin A supplementation in CVI, perhaps resulting in enhanced immunoglobulin synthesis and downregulated inflammatory responses.