Fructose:Glucose Ratios—A Study of Sugar Self-Administration and Associated Neural and Physiological Responses in the Rat

Nutrients

AnneMarie Levy²  Paul Marshall²  Yan Zhou³  Mary Jeanne Kreek³  Katrina Kent²  Stephen Daniels²  Ari Shore²  Tiana Downs²  Maria Fernanda Fernandes²  David M. Mutch¹ 

[1] Department of Human Health & Nutritional Science, University of Guelph, Guelph, ON N1G 2W1, Canada; E-Mail:;Department of Psychology, University of Guelph, Guelph, ON N1G 2W1, Canada; E-Mails:;Laboratory of Addictive Diseases, Rockefeller University, New York, NY 10065, USA; E-Mails:

关键词: fructose;    glucose;    self-administration;    hypothalamus;    nucleus accumbens;    dopamine 2 receptor;    mu opioid receptor;    fatty acid;    hepatic;    rat;   

DOI  :  10.3390/nu7053869

来源: mdpi

【 摘 要 】

This study explored whether different ratios of fructose (F) and glucose (G) in sugar can engender significant differences in self-administration and associated neurobiological and physiological responses in male Sprague-Dawley rats. In Experiment 1, animals self-administered pellets containing 55% F + 45% G or 30% F + 70% G, and Fos immunoreactivity was assessed in hypothalamic regions regulating food intake and reward. In Experiment 2, rats self-administered solutions of 55% F + 42% G (high fructose corn syrup (HFCS)), 50% F + 50% G (sucrose) or saccharin, and mRNA of the dopamine 2 (D2R) and mu-opioid (MOR) receptor genes were assessed in striatal regions involved in addictive behaviors. Finally, in Experiment 3, rats self-administered HFCS and sucrose in their home cages, and hepatic fatty acids were quantified. It was found that higher fructose ratios engendered lower self-administration, lower Fos expression in the lateral hypothalamus/arcuate nucleus, reduced D2R and increased MOR mRNA in the dorsal striatum and nucleus accumbens core, respectively, as well as elevated omega-6 polyunsaturated fatty acids in the liver. These data indicate that a higher ratio of fructose may enhance the reinforcing effects of sugar and possibly lead to neurobiological and physiological alterations associated with addictive and metabolic disorders.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.