TITLE:
Impacts of Mild Hypothermia on LPS-Mediated TLR4/NF-κB Signaling Pathway in Microglia
AUTHORS:
Li Liu, Xiaoshuang Li, Yaoyao Wang, Fang Cao, Shihai Zhang, Zhen Zhan, Yangyang Meng, Qilian Xie
KEYWORDS:
Hypothermia, Lipopolysaccharide, Microglia, Toll-Like Receptor 4, NF-κB, Tumor Necrosis Factor-α, Interleukin-10
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.7 No.2,
February
22,
2019
ABSTRACT: Background: Existing
studies have found that some inflammatory factors cause brain cell damage
through the TLR4/NF-κB pathway, and that mild hypothermia has a protective
effect on nerve cells. It is not clear whether the mild hypothermic brain
protection is achieved through the TLR4/NF-κB pathway in microglia. Objective:
To investigate the impacts of mild hypothermia on lipopolysaccharide (LPS)-mediated
TLR4/NF-κB signaling pathway in microglia. Method: The cultured
microglia cells in vitro were divided
into the NS group and the LPS group at 33?C and 37?C, respectively;
quantitative RT-PCR was performed to detect the expressions of TLR4 and NF-κB
mRNA in the microglia, Western blot was used to detect the expressions of TLR4
and NF-κB protein in the microglia, and ELISA was performed to detect the
levels of tumor necrosis factor α (TNF-α) and interleukin-10 (IL-10) in
the culture medium. Results: Under the LPS stimulation, the mRNA and
protein expressions of TLR4 and NF-κB at different time points had significant
changes between the normothermia group and the mild hypothermia group, in which
the expressions in the former group were firstly increased and then decreased,
while those in the latter showed a continuous increasing trend (P α in all
the groups presented the trend of first-increasing then-decreasing, while IL-10
exhibited one slow linear increasing trend (P Conclusions: Mild
hypothermia could inhibit the mRNA and
protein expressions of LPS-mediated TLR4/NF-κB signaling pathway in the
microglia, and inhibit the production and release of downstream inflammatory
cytokines (TNF-α and IL-10).