Effects of propofol on the mRNA expression of toll-like receptor 4 in BV-2 cells during mimic ischemia-reperfusion injury in vitro

Abstract

This study investigated the effects of propofol on the mRNA expression of Toll-like receptor-4 (TLR4) in BV-2 cells during mimic ischemia-reperfusion (I/R) injury in vitro. BV-2 cells, a mouse microglia line, were cultured and divided into 4 groups at random: control group (group C), ischemia/reperfusion group (group I/R), low-dose propofol (25 μmol/L) intervention group (group PF₂₅) and high-dose propofol (100 μmol/L) intervention group (group PF₁₀₀). The mRNA expression of TLR4 and NF-κB was measured by means of RT-PCR. TNF-α levels in the supernatants of BV-2 cells were detected by ELISA. The results showed that the mRNA expression of TLR4 and NF-κB was significantly higher in groups I/R, PF₂₅ and PF₁₀₀ than in group C (P<0.01). And the TNF-α level in the supernatants was elevated in groups I/R, PF₂₅ and PF₁₀₀ as compared with that in group C (P<0.01). After pre-treatment with propofol, the mRNA expressions of TLR4 and NF-κ B and the TNF-α level were significantly decreased in groups PF₂₅ and PF₁₀₀ in comparison to those in group I/R (P<0.01). And the decrease in those indicators was more significant in group PF₁₀₀ than in group PF₂₅ (P<0.01). It was concluded that propofol exerted brain-protecting effects during I/R injury by suppressing the mRNA expressions of TLR4 and NF-κB and deceasing the TNF-α level.

Keywords

propofol / Toll-like receptor-4 / ischemia/reperfusion / microglia

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