Effects of obesity on insulin: insulin-like growth factor 1 hybrid receptor expression and Akt phosphorylation in conduit and resistance arteries.
Authors of this article are:
Mughal RS1, Bridge K1, Buza I2, Slaaby R2, Worm J2, Klitgaard-Povlsen G2, Hvid H2, Schiødt M2, Cubbon R1, Yuldasheva N1, Skromna A1, Makava N1, Skytte-Olsen G2, Kearney MT1.
A summary of the article is shown below:
Insulin and insulin-like growth factor-1 stimulate specific responses in arteries, which may be disrupted by diet-induced obesity. We examined (1) temporal effects of high-fat diet compared to low-fat diet in mice on insulin receptor, insulin-like growth factor-1 receptor, insulin receptor/insulin-like growth factor-1 receptor hybrid receptor expression and insulin/insulin-like growth factor-1-mediated Akt phosphorylation in aorta; and (2) effects of high-fat diet on insulin and insulin-like growth factor-1-mediated Akt phosphorylation and vascular tone in resistance arteries. Medium-term high-fat diet (5 weeks) decreased insulin-like growth factor-1 receptor expression and increased hybrid expression (~30%) only. After long-term (16 weeks) high-fat diet, insulin receptor expression was reduced by ~30%, insulin-like growth factor-1 receptor expression decreased a further ~40% and hybrid expression increased a further ~60%. Independent correlates of hybrid receptor expression were high-fat diet, duration of high-fat diet and plasma insulin-like growth factor-1 (all p < 0.05). In aorta, insulin was a more potent activator of Akt than insulin-like growth factor-1, whereas in resistance arteries, insulin-like growth factor-1 was more potent than insulin. High-fat diet blunted insulin-mediated vasorelaxation ( p < 0.01) but had no effect on insulin-like growth factor-1-mediated vasorelaxation in resistance arteries. Our findings support the possibility that hybrid receptor level is influenced by nutritional and metabolic cues. Moreover, vessel-dependent effects of insulin and insulin-like growth factor-1 on vascular tone and Akt activation may have implications in treating obesity-related vascular disease.
Check out the article’s website on Pubmed for more information:
This article is a good source of information and a good way to become familiar with topics such as: IGF-1 receptors;Obesity;hybrid receptors.
Categories: Science News