Fructose induced lipogenesis: from sugar to fat to insulin resistance.

Departments of Internal Medicine, Yale University School of Medicine, New Haven, CT 06536-8012, USA.
Trends in Endocrinology and Metabolism (Impact Factor: 8.87). 11/2010; 22(2):60-5. DOI: 10.1016/j.tem.2010.10.003
Source: PubMed

ABSTRACT Increasing consumption of sugars is one of the contributing factors to the obesity epidemic. Both cane sugar and high-fructose corn syrup contain glucose and fructose. Fructose, in contrast to glucose, is known to potently stimulate lipogenesis, but the mechanisms responsible are not yet fully known. This paper reviews several possible pathways that might be involved, such as activation of pyruvate dehydrogenase, and transcriptional activation of sterol regulatory element binding protein 1c by key regulators such as peroxisome proliferator activated receptor-γ co-activator 1β and the splice variant of X-box binding protein 1. Together, these pathways might establish a feed forward cycle that can rapidly increase hepatic lipogenesis. As a result, dietary fructose might promote the development of nonalcoholic fatty liver disease, which in and of itself, can result in hepatic insulin resistance, a key feature of type 2 diabetes mellitus.

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