Objective: Transmembrane protein 88 (TMEM88), a new protein of increasing concern existed in cell membrane, inhibits the typical Wnt/β-catenin signaling pathway to play a regulatory role on cell proliferation by binding to Dishevelled-1. Until recently, the connection between TMEM88 and alcoholic liver disease is unknown. In this research, we explored the effect of TMEM88 on the secretion of inflammatory cytokines in ethanol (EtOH)-induced RAW264.7 cells, moreover, the function of YAP signaling pathway in EtOH-induced RAW264.7 cells were investigated.
Methods: We administered TMEM88 adenovirus (ADV-TMEM88) by tail vein injection into C57BL/6J mice in vivo. In vitro, RAW264.7 murine macrophages were stimulated with EtOH and were transfected with pEGFP-C1-TMEM88 and TMEM88 siRNA, respectively, protein expression and mRNA expression of IL-6 and IL-1β were assessed by Western Blotting and RT-qPCR, respectively.
Results: Our group found that the overexpression of TMEM88 led to an up-regulation of IL-6 and IL-1β secretion, hinting that it had the possibility of linking with the initiation, the development, and the end of inflammation. In addition to that, TMEM88 silencing reduced the secretion of IL-6 and IL-1β in RAW264.7 cells. Moreover, we demonstrated that the YAP signaling pathway under the action of EtOH was activated by TMEM88.
Conclusions: All in all, these experimental outcomes indicated that TMEM88 had an indispensable impact on EtOH-induced secretion of inflammatory cytokines (IL-6 and IL-1β) in RAW264.7 cells through YAP signaling pathway.
Keywords: EtOH; RAW264.7 cells; TMEM88; YAP.