Mancini Sarah J, White Anna D, Bijland Silvia, Rutherford Claire, Graham Delyth, Richter Erik A, Viollet Benoit, Touyz Rhian M, Palmer Timothy M, Salt Ian P
Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark.
Mol Cell Endocrinol. 2017 Jan 15;440:44-56. doi: 10.1016/j.mce.2016.11.010. Epub 2016 Nov 11.
Inflammation of adipose tissue in obesity is associated with increased IL-1β, IL-6 and TNF-α secretion and proposed to contribute to insulin resistance. AMP-activated protein kinase (AMPK) regulates nutrient metabolism and is reported to have anti-inflammatory actions in adipose tissue, yet the mechanisms underlying this remain poorly characterised. The effect of AMPK activation on cytokine-stimulated proinflammatory signalling was therefore assessed in cultured adipocytes. AMPK activation inhibited IL-1β-stimulated CXCL10 secretion, associated with reduced interleukin-1 receptor associated kinase-4 (IRAK4) phosphorylation and downregulated MKK4/JNK and IKK/IκB/NFκB signalling. AMPK activation inhibited TNF-α-stimulated IKK/IκB/NFκB signalling but had no effect on JNK phosphorylation. The JAK/STAT3 pathway was also suppressed by AMPK after IL-6 stimulation and during adipogenesis. Adipose tissue from AMPKα1 mice exhibited increased JNK and STAT3 phosphorylation, supporting suppression of these distinct proinflammatory pathways by AMPK in vivo. The inhibition of multiple pro-inflammatory signalling pathways by AMPK may underlie the reported beneficial effects of AMPK activation in adipose tissue.
肥胖状态下脂肪组织的炎症与白细胞介素-1β、白细胞介素-6和肿瘤坏死因子-α分泌增加相关,并被认为与胰岛素抵抗有关。AMP激活的蛋白激酶(AMPK)调节营养物质代谢,据报道在脂肪组织中具有抗炎作用,但其潜在机制仍不清楚。因此,在培养的脂肪细胞中评估了AMPK激活对细胞因子刺激的促炎信号传导的影响。AMPK激活抑制白细胞介素-1β刺激的CXCL10分泌,这与白细胞介素-1受体相关激酶-4(IRAK4)磷酸化减少以及MKK4/JNK和IKK/IκB/NFκB信号传导下调有关。AMPK激活抑制肿瘤坏死因子-α刺激的IKK/IκB/NFκB信号传导,但对JNK磷酸化无影响。在白细胞介素-6刺激后和成脂过程中,JAK/STAT3途径也被AMPK抑制。来自AMPKα1小鼠的脂肪组织显示JNK和STAT3磷酸化增加,支持AMPK在体内对这些不同促炎途径的抑制作用。AMPK对多种促炎信号通路的抑制作用可能是其在脂肪组织中激活所报道的有益作用的基础。