生物谷：來(lái)自Warwick大學(xué)醫(yī)學(xué)院的科學(xué)家最近發(fā)現(xiàn)維生素B1缺乏是造成糖尿病人的多種血管問(wèn)題的主要原因。糖尿病是目前世界范圍內(nèi)最主要的健康問(wèn)題之一,，它會(huì)造成微血管問(wèn)題,，對(duì)腎臟、視網(wǎng)膜和手臂以及腿部的神經(jīng)造成損傷,，并可能導(dǎo)致心臟病和中風(fēng)等,。
由Paul Thornalley領(lǐng)導(dǎo)的小組最終發(fā)現(xiàn)這些病人血漿中缺少維生素B1,。他們同時(shí)發(fā)現(xiàn)了維生素B1如何作用于糖尿病人并導(dǎo)致血管損傷,。結(jié)果發(fā)表在8月4日的Diabetologia上。小組發(fā)現(xiàn)在1型糖尿病患者血漿中,，維生素B1濃度下降了76%,，而對(duì)于2型糖尿病患者這一數(shù)字是75%。由于之前科學(xué)家通過(guò)測(cè)量紅血球中的轉(zhuǎn)羥乙醛酶來(lái)間接測(cè)量維生素B1濃度,，而這一酶的活性由于THTR-1和RFC-1蛋白維持正常,，因此科學(xué)家一直沒(méi)有發(fā)現(xiàn)維生素B1的下降。
科學(xué)家發(fā)現(xiàn)血管細(xì)胞中維生素B1的減少和微血管并發(fā)癥密切相關(guān),，這似乎和內(nèi)皮細(xì)胞有關(guān),，并且會(huì)使得患動(dòng)脈硬化癥的風(fēng)險(xiǎn)大大增加。小組同時(shí)發(fā)現(xiàn)糖尿病人血漿維生素B1的減少不是由于食物攝取引起的,，而是和血液中大量維生素B1進(jìn)入尿中有關(guān),。
科學(xué)家認(rèn)為還需要進(jìn)行下列研究：確認(rèn)其它國(guó)家糖尿病人群的血液維生素B1情況；評(píng)估使用維生素B1和相關(guān)維生素衍生物治療和預(yù)防血管損傷的作用,；確認(rèn)大量維生素B1從血液進(jìn)入尿液中的機(jī)制,。 ( 教育部科技發(fā)展中心)
英文原文鏈接：http://www.physorg.com/news105715539.html
原始出處:
High prevalence of low plasma thiamine concentration in diabetes linked to a marker of vascular disease
2007年8月4日
DOI 10.1007/s00125-007-0771-4
P. J. Thornalley1, 2 , R. Babaei-Jadidi1, H. Al Ali1, N. Rabbani1, 2, A. Antonysunil1, 2, J. Larkin1, 2, A. Ahmed3, G. Rayman4 and C. W. Bodmer3
(1) Department of Biological Sciences, University of Essex, Colchester, Essex, UK
(2) Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, University Hospital, Clifford Bridge Road, Coventry, CV2 2DX, UK
(3) Department of Diabetes and Endocrinology, Colchester General Hospital, Colchester, Essex, UK
(4) Ipswich Diabetic Foot Unit and Diabetes Centre, Ipswich Hospital NHS Trust, Ipswich, UK
Received: 23 February 2007 Accepted: 22 June 2007 Published online: 4 August 2007
Abstract
Aims/hypothesis To assess thiamine status by analysis of plasma, erythrocytes and urine in type 1 and type 2 diabetic patients and links to markers of vascular dysfunction.
Methods Diabetic patients (26 type 1 and 48 type 2) with and without microalbuminuria and 20 normal healthy control volunteers were recruited. Erythrocyte activity of transketolase, the concentrations of thiamine and related phosphorylated metabolites in plasma, erythrocytes and urine, and markers of metabolic control and vascular dysfunction were determined.
Results Plasma thiamine concentration was decreased 76% in type 1 diabetic patients and 75% in type 2 diabetic patients: normal volunteers 64.1 (95% CI 58.5–69.7) nmol/l, type 1 diabetes 15.3 (95% CI 11.5–19.1) nmol/l, p < 0.001, and type 2 diabetes 16.3 (95% CI 13.0–9.6) nmol/l, p < 0.001. Renal clearance of thiamine was increased 24-fold in type 1 diabetic patients and 16-fold in type 2 diabetic patients. Plasma thiamine concentration correlated negatively with renal clearance of thiamine (r = −0.531, p < 0.001) and fractional excretion of thiamine (r = −0.616, p < 0.001). Erythrocyte transketolase activity correlated negatively with urinary albumin excretion (r = −0.232, p < 0.05). Thiamine transporter protein contents of erythrocyte membranes of type 1 and type 2 diabetic patients were increased. Plasma thiamine concentration and urinary excretion of thiamine correlated negatively with soluble vascular adhesion molecule-1 (r = −0.246, p < 0.05, and −0.311, p < 0.01, respectively).
Conclusions/interpretation Low plasma thiamine concentration is prevalent in patients with type 1 and type 2 diabetes, associated with increased thiamine clearance. The conventional assessment of thiamine status was masked by increased thiamine transporter content of erythrocytes.
Keywords Adhesion molecules - Microalbuminuria - Thiamine - Type 1 diabetes - Type 2 diabetes
