Nicotinuric acid: A potential marker of metabolic syndrome through a metabolomics-based approach

OBJECTIVE - Metabolic syndrome is a multiplex disorder and puts patients on the road to type 2 diabetes and atherosclerotic cardiovascular diseases. However, a surrogate biomarker in plasma or urine in fully re flecting features of metabolic syndrome has not been explored. RESEARCH DESIGN AND METHODS - Urine metabolomics has potential utility in metabolic pro filing because urine metabolites analysis re flects global out flux of metabolic change. Accordingly, we collected data on subjects (n = 99) with overweight, dyslipidemia, hypertension or impaired glucose tolerance and took a metabolomics approach to analyze the metabolites of urine revealed in metabolic syndrome by high-performance liquid chromatography- time-of- flight mass spectrometry and elicit potential biomarkers to picture metabolic syndrome. RESULTS - Our results revealed that the urine nicotinuric acid value of subjects with diabetes (HbA_1c ≥6.5% or those receiving diabetes medications) (n = 25) was higher than subjects without diabetes (n = 37) (221 ± 31 vs. 152 ± 13 X 10³ mAU, P = 0.0268). Moreover, urinary nicotinuric acid level was positively correlated with body mass index, blood pressure, total cholesterol, low-density lipoprotein cholesterol, triacylglycerol and high sensitivity C-reactive protein, but negatively correlated with high-density lipoprotein cholesterol. CONCLUSIONS - This is the first study, to our knowledge, to propose that nicotinuric acid represents an important pathogenicmechanism in process from metabolic syndrome to diabetes and atherosclerotic cardiovascular disease.