Dietary Fructose Feeding Increases Adipose Methylglyoxal Accumulation in Rats in Association with Low Expression and Activity of Glyoxalase-2

Nutrients

Christopher Masterjohn¹  Youngki Park¹  Jiyoung Lee¹  Sang K. Noh²  Sung I. Koo¹ 

[1] Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06269, USA; E-Mails:;Department of Food and Nutrition, Changwon National University, Changwon 641-773, Korea; E-Mail:

关键词: fructose;    glyoxalase I;    glyoxalase II;    pyruvaldehyde;    rats;    Sprague-Dawley;   

DOI  :  10.3390/nu5083311

来源: mdpi

【 摘 要 】

Methylglyoxal is a precursor to advanced glycation endproducts that may contribute to diabetes and its cardiovascular-related complications. Methylglyoxal is successively catabolized to d-lactate by glyoxalase-1 and glyoxalase-2. The objective of this study was to determine whether dietary fructose and green tea extract (GTE) differentially regulate methylglyoxal accumulation in liver and adipose, mediated by tissue-specific differences in the glyoxalase system. We fed six week old male Sprague-Dawley rats a low-fructose diet (10% w/w) or a high-fructose diet (60% w/w) containing no GTE or GTE at 0.5% or 1.0% for nine weeks. Fructose-fed rats had higher (P < 0.05) adipose methylglyoxal, but GTE had no effect. Plasma and hepatic methylglyoxal were unaffected by fructose and GTE. Fructose and GTE also had no effect on the expression or activity of glyoxalase-1 and glyoxalase-2 at liver or adipose. Regardless of diet, adipose glyoxalase-2 activity was 10.8-times lower (P < 0.05) than adipose glyoxalase-1 activity and 5.9-times lower than liver glyoxalase-2 activity. Adipose glyoxalase-2 activity was also inversely related to adipose methylglyoxal (r = −0.61; P < 0.05). These findings suggest that fructose-mediated adipose methylglyoxal accumulation is independent of GTE supplementation and that its preferential accumulation in adipose compared to liver is due to low constitutive expression of glyoxalase-2.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.