The Potential Inflammatory Role of IL-6 Signalling in Perturbing the Energy Metabolism Function by Stimulating the Akt-mTOR Pathway in Jurkat T Cells

Numerous studies have reported that increased interleukin 6 (IL-6) and soluble IL-6 receptor (sIL-6) levels induce inflammatory conditions. However, the exact mechanisms by which IL-6 drives inflammatory conditions remain unclear. Therefore, we investigated the potential role of IL-6/sIL-6R in inducing energy metabolism, including glycolysis, oxidative phosphorylation, lactate secretion and Akt/ mTOR phosphorylation, in Jurkat cells, and whether IL-6 would increase the risk of developing inflammatory conditions due to the high metabolic profile of the T cells. Jurkat CD4 T-cell lines were stimulated with IL-6/sIL-6R for 24 h prior to 48-h stimulation with anti-CD3/CD28. Lactate secretion, glycolysis and oxidative phosphorylation levels were characterized using the Seahorse XF analyser. The Akt and mTOR phosphorylation status was detected using Western blotting. IL-6/sIL-6R significantly induced glycolysis and oxidative phosphorylation and their related parameters, including glycolytic capacity and maximal respiration, followed by significantly increased lac-tate secretion. Akt and mTOR phosphorylation were increased, which could have resulted from energy metabolism. Here we show that IL-6 enhanced the metabolic profile of Jurkat cells. This effect could have consequences for the metabolism-related signalling pathways, including Akt and mTOR, suggesting that IL-6 might promote T-cell energy metabolism, where T-cell hyperactivity might increase the inflammatory disease risk. The findings should be validated using studies on primary cells isolated from humans.