Irisin alleviates renal injury caused by sepsis via the NF-κB signaling pathway

Renal injury caused by sepsis is a difficult point in the field of critical care medicine today, which seriously endangers the health of patients. The aim of our paper was to study the role of irisin in the inflammation and apoptosis of renal injury caused by sepsis and its potential mechanism of action.

Lipopolysaccharide (LPS) was utilized to establish an acute kidney injury model. HK-2 cells were divided into 3 groups: control group, LPS group, LPS+irisin group. The expression of TNF-α, IL-1β, Bcl-2, and Bax were detected using Western blot. Commercial enzyme-linked immunosorbent assay (ELISA) kits were used to detect the levels of TNF-α, IL-6, and IL-1β in the cell supernatant. The LDH content was detected to observe cell damage. TUNEL staining and flow cytometry were to investigate the apoptosis in three groups. The viability of HK-2 cells was detected using Cell Counting Kit-8 (CCK-8) assay.

After HK-2 cells were treated with LPS, the LDH content in the cell supernatant was greatly increased, and the expression of TNF-α, IL-6, and IL-1β was also significantly increased. However, after treatment with irisin, LDH content and expression of inflammatory factors were significantly suppressed. Similarly, LPS treatment greatly elevated the levels of TNF-α, IL-1β, Bax, p65 and IκKα, as well as inhibited the expression of Bcl-2 and IκB-α. However, irisin treatment reversed these situations. In addition, the number of TUNEL-positive cells and the apoptotic rate were also greatly decreased in LPS+irisin group compared with those in LPS group.

Irisin could inhibit inflammation and apoptosis of HK-2 cells treated with LPS via the NF-κB pathway.