Lipopolysaccharide induces TREM-1-dependent HIF-1 α expression in human keratinocyte cell line.

Lipopolysaccharide induces TREM-1-dependent HIF-1α expression in human keratinocyte cell line.
Cell Biol Int. 2016 Oct 15;:
Authors: Tu C, Wang S, Hu X, Wang W, Dong Y, Xiao S, Wang X
Abstract
Bacterial infection is an important factor that can trigger and exacerbate psoriasis. The protein triggering receptor expressed on myeloid cells type-1 (TREM-1) is overexpressed in psoriasis and decreased after a successful treatment. Hypoxia inducible factor-1α (HIF-1α), subunit of the transcription factor HIF-1, has participated in angiogenesis and inflammation in psoriasis. Increased expressions of TREM-1 and HIF-1α are associated with the infection of microbial pathogens. However, the association between TREM-1 and HIF-1α still need to be elucidated. Results of immunofluorescence showed an overexpression of TREM-1 and HIF-1α in HaCaT keratinocytes exposed to 1 µg/mL of lipopolysaccharide (LPS). Particularly, silencing of TREM-1 expression by siRNA suppressed the inducible effect of LPS on phosphoinositide 3-kinase (PI3K)/Akt, the critical transduction mediator, and HIF-1α. Furthermore, the PI3K inhibitor wortmannin effectively blocked the increased level of HIF-1α induced by LPS. However, there was no significant change in LPS-induced expression of TREM-1. Expressions of TREM-1, HIF-1α, and phosphorylated Akt proteins were further examined by real-time PCR and western blot, respectively. Our data suggest that TREM-1 and HIF-1α ...

Source: Cell Biology International - October 14, 2016 Category: Cytology Authors: Tu C, Wang S, Hu X, Wang W, Dong Y, Xiao S, Wang X Tags: Cell Biol Int Source Type: research