The Dualistic Effect of COX-2-Mediated Signaling in Obesity and Insulin Resistance
AbstractObesity and insulin resistance are two major risk factors for the development of metabolic syndrome, type 2 diabetes and associated cardiovascular diseases (CVDs). Cyclooxygenase (COX), a rate-limiting enzyme responsible for the biosynthesis of prostaglandins (PGs), exists in two isoforms: COX-1, the constitutive form, and COX-2, mainly the inducible form. COX-2 is the key enzyme in eicosanoid metabolism that converts eicosanoids into a number of PGs, including PGD2, PGE2, PGF2α, and prostacyclin (PGI2), all of which exert diverse hormone-like effects via autocrine or paracrine mechanisms. The COX-2 gene and immunoreactive proteins have been documented to be highly expressed and elevated in adipose tissue (AT) under morbid obesity conditions. On the other hand, the environmental stress-induced expression and constitutive over-expression of COX-2 have been reported to play distinctive roles under different pathological and physiological conditions; i.e., over-expression of the COX-2 gene in white AT (WAT) has been shown to induce de novo brown AT (BAT) recruitment in WAT and then facilitate systemic energy expenditure to protect mice against high-fat diet-induced obesity. Hepatic COX-2 expression was found to protect against diet-induced steatosis, obesity, and insulin resistance. However, COX-2 activation in the epidydimal AT is strongly correlated with the development of AT inflammation, insulin resistance, and fatty liver in high-fat-diet-induced obese rats. This review will provide updated information regarding the role of COX-2-derived signals in the regulation of energy metabolism and the pathogenesis of obesity and MS. View Full-Text
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Chan, P.-C.; Liao, M.-T.; Hsieh, P.-S. The Dualistic Effect of COX-2-Mediated Signaling in Obesity and Insulin Resistance. Int. J. Mol. Sci. 2019, 20, 3115.
Chan P-C, Liao M-T, Hsieh P-S. The Dualistic Effect of COX-2-Mediated Signaling in Obesity and Insulin Resistance. International Journal of Molecular Sciences. 2019; 20(13):3115.Chicago/Turabian Style
Chan, Pei-Chi; Liao, Min-Tser; Hsieh, Po-Shiuan. 2019. "The Dualistic Effect of COX-2-Mediated Signaling in Obesity and Insulin Resistance." Int. J. Mol. Sci. 20, no. 13: 3115.
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