ABSTRACT
Objective:To investigate the role of formyl peptide receptor 2 （FPR2） in the inhibitory effects of Buyang Huanwutang （BYHWT） on the oxidative stress and its protective effects on cerebral ischemia-reperfusion in rats. Method:Forty-eight male SD rats were randomly divided into sham group， model group， BYHWT group and BYHWT combined with FPR2 inhibitor （Boc-2） group. In the sham group， only the vessels were isolated. In other groups， the middle cerebral artery occlusion （MCAO） model was constructed using the modified Longa method and reperfused after 2 h of ischemia. BYHWT （16 g·kg<sup>-1</sup>） was given by gavaged twice daily after reperfusion in BYHWT group and BYHWT+Boc-2 group. Boc-2 （0.4 mg·kg<sup>-1</sup>） was injected intraperitoneally 30 min before surgery. Equal volume of saline were given instead in sham and model group. After 24 h of reperfusion， Fluoro-Jade C （FJC） staining was performed to observe the changes in the number of FJC-positive cells. Western blot was performed to detect the expression of apoptosis-related B-cell lymphoma-2 (Bcl-2)， Bcl-2 associated X (Bax)， and cleaved aspartic acid cysteine proteolytic enzyme-3（Caspase-3）. Besides， superoxide dismutase （SOD）， malondialdehyde （MDA）， glutathione （GSH）， and nitric oxide （NO） was measured. The mean fluorescence intensity of nicotinamide adenine dinucleotide phosphate Ⅱ（NADPH） oxidase 2 （NOX2） was examined by immunofluorescence. Result:Compared with sham group， the model group showed increased number of FJC-positive cells （<italic>P</italic><0.01）， decreased Bcl-2 expression （<italic>P</italic><0.01）， increased Bax and cleaved Caspase-3 expression （<italic>P</italic><0.01）， increased NO and MDA content （<italic>P</italic><0.05，<italic>P</italic><0.01）， decreased GSH and SOD activities （<italic>P</italic><0.05，<italic>P</italic><0.01）， and increased NOX2 expression （<italic>P</italic><0.01）. Compared with model group， there were decreased FJC-positive cells （<italic>P</italic><0.01）， up-regulated Bcl-2 expression （<italic>P</italic><0.01） with down-regulated cleaved Caspase-3 and Bax （<italic>P</italic><0.05，<italic>P</italic><0.01）， decreased NO and MDA （<italic>P</italic><0.05，<italic>P</italic><0.01） with increased GSH and SOD （<italic>P</italic><0.01）， and decreased NOX2 expression （<italic>P</italic><0.01） in the BYHWT group. All the above effects were partially blocked by Boc-2. Conclusion:BYHWT can reduce oxidative stress injury and inhibit apoptosis in cerebral ischemia/reperfusion rats， which may be related with the down-regulation of NOX2 expression by FPR2.
ABSTRACT
Aim To investigate whether RvDl regulates microglial polarization through FPR2 and alleviates the inflammatory damage after cerebral ischemiareperfusion. Methods The middle cerebral artery occlusion (MCAO) model was established by Longa method. The rats after MCAO were randomly divided into; model group, RvD1 group and RvD1 + Boc-2 group, and a sham-operated group was set up as control as well. Cerebral infarct volume was measured, MPO activities in rat brain were measured by immunofluorescence. The expression and localization of FPR2/Iba-1, CD16/Iba-1 and CD206/Iba-1 were detected by immunofluorescence double labeling method. The expressions of TNF-α, IL-1β and iNOS in M1 and TGF-β, IL-10, Arg-1 in M2 were detected by RT-qPCR. Results RvDl significantly reduced cerebral infarction volume and the expression of MPO, and its receptor FPR2 was expressed in microglia. RvD1 down-regulated M1 markers CD16
ABSTRACT
<b>Objective::To investigate the mechanism of Buyang Huanwu Tang (BYHWT) in improving synaptic structural plasticity after cerebral ischemia-reperfusion in rats. <b>Method::Middle cerebral artery occlusion and reperfusion model was established. SD rats were randomly divided into sham-operated group, model group, BYHWT group, BYHWT+ Gap26(connexin43 inhibitor)groups. BYHWT was given twice a day(16 g·kg<sup>-1</sup>), Gap26 was intraperitoneally injected once a day since the third day after surgery (25 g·kg<sup>-1</sup>). Brain was taken out at the 7<sup>th</sup> day. The changes of neuronal synaptic and gap junction ultrastructure were observed by transmission electron microscopy. Synaptophysin (SYN) and growth-associated protein-43 (GAP-43) protein expression were detected by Western blot and immunofluorescence. <b>Result::The structure of synapses was integrated, and the gap junctions were clear in sham-operated group. In the hippocampus of model group, the structure was destroyed, and the gap junctions disappeared. Compared with the sham-operated group, model group up-regulated the expressions of SYN and GAP-43 (<italic>P</italic><0.05, <italic>P</italic><0.01). In the hippocampus of BYHWT group, the structure was close to the normal. Furthermore, BYHWT up-regulated the expressions of SYN and GAP-43 (<italic>P</italic><0.05, <italic>P</italic><0.01). However, after the combined administration with Cx43 inhibitor (Gap26), the damage of synaptic structural decreased, only a small number of gap junctions with the structural integrity can be seen, and the effect of BYHWT on SYN and GAP-43 was inhibited (<italic>P</italic><0.05, <italic>P</italic><0.01). <b>Conclusion::BYHWT could improve the hippocampal synaptic structural plasticity obviously after the CIRI. The mechanism may be related to the increase of the expression of Cx43 and the promotion of the intervention of SYN and GAP-43.