ABSTRACT
Objective This study aims to investigate the effect of Lipoxin A4 receptor on acute lung injury (ALI) induced by intestine ischemia-reperfusion (IIR). Methods Thirty-two 8-week old SD rats were randomly divided into four groups: sham, intestine ischemia-reperfusion (IIR), IIR + BML111 (BML-111), Boc-2 + IIR +BML111 (Boc-2). BML-111 (1 mg/kg) was given intraperitoneally at the onset of reperfusion in the BML-111 and the Boc-2 group. Boc-2 (50 μg/kg) was given intraperitoneally after anesthesia in the Boc-2 group. Rats were subjected to superior mesenteric artery occlusion consisting of 45-min ischemia and 6-h reperfusion, and the sham laparotomy was served as controls. The lung pathology was assayed by the H&E staining. Lung water content was detected using dry/wet ratio. Concentrations of TNF-α, IL-1β, and IL-6 in lung tissue were determined by ELISA. The protein expression of p38 MAPK and NF-κB of lung was assayed by western blot. Results IIR induced serious ALI, with poor lung pathology and increased lung water content, elevation of TNF-α, IL-1β, and IL-6 levels in lung, accompanied with activation of p38 MAPK/NF-κB pathway. However, BML-111 could inhibit the activation of p38 MAPK/NF-κB pathway, leading to the reductions of TNF-α, IL-1β, and IL-6 in lung and attenuation of IIR-induced ALI. Conclusion BML-111 treatment could attenuate inflammation in lung after IIR injury via inactivating the p38 MAPK/NF-κB signaling pathway.
ABSTRACT
Objective To investigate the effects of the c-Jun N-terminal kinase (JNK)pathway on isoflurane induced neuronal apoptosis and the proteins expression of phospho-JNK,Bcl-2 and Bax in the hippocampi of neonatal rats.Methods Forty-eight neonatal rats at postnatal day 7 (P7) were randomly assigned into 4 groups:DMSO control group (group D),SP600125 control group (group SP30),isoflurane + DMSO group (group Iso +D),isoflurane + SP600125 group (group Iso + SP30).Rats were exposed to air (control group) or 1.1％ isoflurane (isoflurane group) for 4 h.The JNK inhibitor SP600125 at 30 μg or 12％ DMSO 5 μl was intraventricularly administered 20 min before the exposure.The brains of some rats in each group were perfused and embedded by paraffin 6 h after the exposure.Neuronal apoptosis in the hippocampi CA1 area was detected by TUNEL (n =6).The fresh hippocampi of other rats in each group were dissected 6 h after the exposure and the proteins expression of phospho-JNK,Bcl-2 and Bax were detected by Western blot (n =6).One way ANOVA were used for data analysis among groups.Results The number of TUNEL positive cells in the hippocampal CA1 regions in group Iso +D (135.72 ±21.26 per mm2) increased by 5 folds compared with group D (24.07 ± 1.35 per mm2) (P＜0.01) ;while the number of apoptotic cells in group Iso + SP30 (42.49 ± 5.56 per mm2) decreased by 84％ (P ＜ 0.05)compared with group Iso + D.The expression of phospho-JNK p46 kd in group Iso + D increased by 44.1％ (P ＜0.01),while both phospho-JNK at p46kd and at p54kd in group Iso + SP30 decreased significantly (P＜0.05,P ＜0.01) compared with group Iso + D.The protein expression of Bax increased 1.5 folds (P＜0.05) and Bcl-2 decreased by 42.2％ (P＜0.05) in group Iso + D compared to group D;while SP600125 significantly decreased expression of Bax (P ＜0.05) and increased expression of Bcl-2 (P＜0.01).Conclusion JNK activation contributes to isoflurane-induced neuroapoptosis in the developing brain.Maintaining Bcl-2 expression and inhibiting Bax expression may be involved in the neuroprotective effects of SP600125.