Humans ; Gastrointestinal Microbiome ; Atherosclerosis ; Methylamines/metabolism*

OBJECTIVEThis review aimed to summarize the relationship between intestinal microbiota metabolism and cardiovascular disease (CVD) and to propose a novel CVD therapeutic target.

DATA SOURCESThis study was based on data obtained from PubMed and EMBASE up to June 30, 2015. Articles were selected using the following search terms: "Intestinal microbiota", "trimethylamine N-oxide (TMAO)", "trimethylamine (TMA)", "cardiovascular", and "atherosclerosis".

STUDY SELECTIONStudies were eligible if they present information on intestinal microbiota metabolism and atherosclerosis. Studies on TMA-containing nutrients were also included.

RESULTSA new CVD risk factor, TMAO, was recently identified. It has been observed that several TMA-containing compounds may be catabolized by specific intestinal microbiota, resulting in TMA release. TMA is subsequently converted to TMAO in the liver. Several preliminary studies have linked TMAO to CVD, particularly atherosclerosis; however, the details of this relationship remain unclear.

CONCLUSIONSIntestinal microbiota metabolism is associated with atherosclerosis and may represent a promising therapeutic target with respect to CVD management.

Atherosclerosis ; metabolism ; microbiology ; Gastrointestinal Microbiome ; physiology ; Humans ; Methylamines ; metabolism

The association among plasma trimethylamine-N-oxide (TMAO), FMO3 polymorphisms, and chronic heart failure (CHF) remains to be elucidated. TMAO is a microbiota-dependent metabolite from dietary choline and carnitine. A prospective study was performed including 955 consecutively diagnosed CHF patients with reduced ejection fraction, with the longest follow-up of 7 years. The concentrations of plasma TMAO and its precursors, namely, choline and carnitine, were determined by liquid chromatography-mass spectrometry, and the FMO3 E158K polymorphisms (rs2266782) were genotyped. The top tertile of plasma TMAO was associated with a significant increment in hazard ratio (HR) for the composite outcome of cardiovascular death or heart transplantation (HR = 1.47, 95% CI = 1.13-1.91, P = 0.004) compared with the lowest tertile. After adjustments of the potential confounders, higher TMAO could still be used to predict the risk of the primary endpoint (adjusted HR = 1.33, 95% CI = 1.01-1.74, P = 0.039). This result was also obtained after further adjustment for carnitine (adjusted HR = 1.33, 95% CI = 1.01-1.74, P = 0.039). The FMO3 rs2266782 polymorphism was associated with the plasma TMAO concentrations in our cohort, and lower TMAO levels were found in the AA-genotype. Thus, higher plasma TMAO levels indicated increased risk of the composite outcome of cardiovascular death or heart transplantation independent of potential confounders, and the FMO3 AA-genotype in rs2266782 was related to lower plasma TMAO levels.
Carnitine ; Choline/metabolism* ; Chronic Disease ; Heart Failure/genetics* ; Humans ; Methylamines ; Oxygenases ; Prospective Studies

Diabetic nephropathy is one of the various complications of diabetes mellitus, affecting patients for lifetime. Earlier studies have revealed that genipin can not only improve diabetes, but also induce cytotoxicity. Therefore, it is not clear which effect of genipin on kidneys occurs, when it is used in the treatment of diabetes. In the present study, we performed nuclear magnetic resonance (NMR)-based metabolomics analysis of urine and kidney tissue samples obtained from diabetic rats to explore the change of endogenous metabolites associated with diabetes and concomitant kidney disease. Nine significant differential metabolites that were closely related to renal function were screened. They were mainly related to three metabolic pathways: synthesis and degradation of ketone bodies, glycine, serine and threonine metabolism, and butanoate metabolism, which are involved in methylamine metabolism, energy metabolism and amino acid metabolism. In addition, after the intervention of genipin, the metabolic levels of all the metabolites tended to be normal, indicating a protective effect of genipin on kidneys. Our results may be helpful for understanding the antidiabetic effect of genipin.
Amino Acids ; metabolism ; Animals ; Diabetes Mellitus, Experimental ; chemically induced ; drug therapy ; metabolism ; urine ; Energy Metabolism ; drug effects ; Hypoglycemic Agents ; pharmacology ; Iridoids ; pharmacology ; Kidney ; drug effects ; metabolism ; Male ; Metabolic Networks and Pathways ; drug effects ; Metabolome ; drug effects ; Metabolomics ; Methylamines ; metabolism ; Proton Magnetic Resonance Spectroscopy ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the toxic effects of Glucoside Tripterygium total on rats with nuclear magnetic resonance (NMR)-based metabonomic method.

METHODThe influence of intragastric administration of Glucoside Tripterygium total suspension at two different doses on endogenetic metabolites in normal rat urine was determined with bio-NMR method then analyzed by pattern recognition technique and partial least-squares discriminant analysis (PLS-DA). Histopathological analysis was carried out.

RESULTEscalations of concentrations of urinary taurine, TMAO and glucose as well as reductions of concentrations of urinary citrate and 2-oxoglutarate were found by analysis of the 1H-NMR spectra, which was coincident with the result of histopathological analysis. The result of pathological examination indicated that pathologic change was not observed in nephridial tissue, but there were obvious changes in hepatic tissue.

CONCLUSIONThe urinary metabomic spectra were closely associated with the hepatic toxicity, which manifested the mitochondrial dysfunctions, the abnormal energy metabolism in TCA cycle as well as the abnormal glucose metabolism.

Animals ; Citric Acid ; urine ; Enteral Nutrition ; Glucose ; metabolism ; Glucosides ; administration & dosage ; Ketoglutaric Acids ; urine ; Least-Squares Analysis ; Liver ; drug effects ; metabolism ; pathology ; Magnetic Resonance Spectroscopy ; methods ; Metabolomics ; Methylamines ; urine ; Plant Extracts ; administration & dosage ; Rats ; Tablets ; administration & dosage ; Taurine ; urine ; Tripterygium ; chemistry