Variability of plasma and urine betaine in diabetes mellitus and its relationship to methionine load test responses: an observational study

Cardiovascular Diabetology

Original Investigation

Warwick J Dellow¹  Sandy Slow²  Peter M George²  Michael Lever²  Stephen T Chambers³  David O McGregor⁴ 

[1] Biochemistry Unit, Canterbury Health Laboratories, PO Box 151, 8140, Christchurch, New Zealand;Biochemistry Unit, Canterbury Health Laboratories, PO Box 151, 8140, Christchurch, New Zealand;Department of Pathology, University of Otaga Christchurch, Christchurch, New Zealand;Department of Pathology, University of Otaga Christchurch, Christchurch, New Zealand;Nephrology Department, Christchurch Hospital, Christchurch, New Zealand;

关键词: Betaine;    Dimethylglycine;    Methionine load;    Homocysteine;   

DOI  :  10.1186/1475-2840-11-34

 received in 2012-02-28, accepted in 2012-04-17,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundSince betaine is an osmolyte and methyl donor, and abnormal betaine loss is common in diabetes mellitus (>20% patients), we investigated the relationship between betaine and the post-methionine load rise in homocysteine, in diabetes and control subjects. The post-methionine load test is reported to be both an independent vascular risk factor and a measure of betaine sufficiency.MethodsPatients with type 2 diabetes (n = 34) and control subjects (n = 17) were recruited. We measured baseline fasting plasma and 4-hour post-methionine load (L-methionine, 0.1 mg/kg body weight) concentrations of homocysteine, betaine, and the betaine metabolite N,N-dimethylglycine. Baseline urine excretions of betaine, dimethylglycine and glucose were measured on morning urine samples as the ratio to urine creatinine. Statistical determinants of the post-methionine load increase in homocysteine were identified in multiple linear regression models.ResultsPlasma betaine concentrations and urinary betaine excretions were significantly (p < 0.001) more variable in the subjects with diabetes compared with the controls. Dimethylglycine excretion (p = 0.00014) and plasma dimethylglycine concentrations (p = 0.039) were also more variable. In diabetes, plasma betaine was a significant negative determinant (p < 0.001) of the post-methionine load increase in homocysteine. However, it was not conclusive that this was different from the relationship in the controls. In the patients with diabetes, a strong relationship was found between urinary betaine excretion and urinary glucose excretion (but not with plasma glucose).ConclusionsBoth high and low plasma betaine concentrations, and high and low urinary betaine excretions, are more prevalent in diabetes. The availability of betaine affects the response in the methionine load test. The benefits of increasing betaine intake should be investigated.

【 授权许可】

CC BY   
© Lever et al.; licensee BioMed Central Ltd. 2012