A simple liquid chromatography/differential ion mobility spectrometry tandem mass spectrometry method for the determination of trimethylamine-N-oxide in human serum: An application in dialysis patients

Effect of Ramadan fasting on chronic inflammation markers and gut bacterial endotoxins among Egyptian hemodialysis patients

BACKGROUND

Chronic kidney disease (CKD) is associated with a state of chronic inflammation. This study aimed to investigate effects of Ramadan fasting on the markers of chronic inflammation and gut bacterial endotoxin levels in maintenance hemodialysis.

METHOD

A prospective self-controlled observational study included 45 patients. Serum levels of High Sensitive CRP (hsCRP), indoxyl sulfate, and trimethylamine-n-levels were measured within a week before and a week after Ramadan fasting.

RESULTS

Twenty-seven patients have fasted more than 15 days (29 ± 2.2 days). The levels of high sensitive C-reactive protein (hsCRP) (median of 62 mg/L vs. 91 mg/L), trimethylamine-n-oxide (TMAO) (median of 4.5 μmoL/L vs. 17 μmoL/L), platelet-to-lymphocyte ratio (PLR) (mean of 98.9 mg/L vs. 111.8 mg/L) and neutrophil-to-lymphocyte ratio (NLR) (median of 1.56 vs. 1.59) were significantly lower after Ramadan fasting with p < 0.001, p < 0.001, p < 0.001, and p = 0.04, respectively.

CONCLUSION

A beneficial effect of Ramadan fasting on levels of bacterial endotoxins and markers of chronic inflammation in hemodialysis patients was observed.

Trimethylamine N-oxide (TMAO) in human health

Due to numerous links between trimethylamine-N-oxide (TMAO) and various disorders and diseases, this topic is very popular and is often taken up by researchers. TMAO is a low molecular weight compound that belongs to the class of amine oxides. It is formed by the process of oxidation of trimethylamine (TMA) by the hepatic flavin monooxygenases (FMO1 and FMO3). TMAO is mainly formed from nutritional substrates from the metabolism of phosphatidylcholine/choline, carnitine, betaine, dimethylglycine, and ergothioneine by intestinal microflora in the colon. Its level is determined by many factors, such as age, gender, diet, intestinal microflora composition, kidney function, and also liver flavin monooxygenase activity. Many studies report a positive relationship between the level of TMAO concentration and the development of various diseases, such as cardiovascular diseases and cardiorenal disorders, including atherosclerosis, hypertension, ischemic stroke, atrial fibrillation, heart failure, acute myocardial infarction, and chronic kidney disease, and also diabetes mellitus, metabolic syndrome, cancers (stomach, colon), as well as neurological disorders. In this review, we have summarized the current knowledge on the effects of TMAO on human health, the relationship between TMAO and intestinal microbiota, the role of TMAO in different diseases, and current analytical techniques used in TMAO determination in body fluids.