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Objective To explore the impact of puerarin treatment on autophagy in rats with traumatic brain injury (TBⅠ) and the underlying mechanism.Methods Seventy five Sprague-Dawley (SD) rats were randomized into 5 groups:sham group (S group,n =15),traumatic brain injury group (TBⅠ group,n =15),TBⅠ + puerarin treatment group (TBⅠ + Pue group,n =15),TBⅠ + JNK inhibitor group (TBⅠ + SP group,n =15),and TBⅠ + JNK activator + Pue (TBⅠ + An + Pue group,n =15).Feeney method was applied to make rats with TBⅠ model.Mter that,head water content and neurological deficit score (NDS) were measured and recorded at day 1,3 and 7 in each group.Western blot was used to measure the JNK activity and autophagic marker proteins,including LC3B and Beclin1.Results Compared to S group,the head water content and NDS were decreased significantly among the others (P ＜ 0.05).The head water content and NDS in TBⅠ + Pue and TBⅠ + SP groups was decreased remarkably compared with TBⅠ group.Combined with puerarin and animycin treatments failed to reduce head water content and NDS compared to the TBⅠ + Pue group.Activated autophagy could be observed in TBⅠ group compared to S group.Compared to group S,LC3Ⅱ,Beclin1 and P-JNK1 were increased significantly.Pue and SP could reduce their expressions,respectively.Combined with puerarin and animycin treatments failed to reduce LC3Ⅱ,Beclin1 and P-JNK1 compared to TBⅠ + Pue group.Conclusions Puerarin could protect rats with TBⅠ via inhibiting autophagy,JNK signal pathway could involve the process of puerarin regulating autophagy.
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Objective To observe the effect of intrathecal injection (IT) of oxycodone hydrochloride on neuropathic pain and spinal cord level of microglial c-Jun N-terminal kinase/chemokine (C-X-C motif) ligand 1 (c-JNK/CXCL) 1signal in rat model of chronic constriction injury (CCI).Methods Male Sprague-Dawley rats were randomly divided into five groups (n =40 per group):sham group (intrathecal normal saline,IT NS),CCI group (CCI + IT NS),oxy group (CCI + IT 5 μg/30 μl oxy),mino group (CCI + IT 5 μg/30 μl Minocycline),and c-JNK inhibitor group (SP group,CCI + IT 5 μg/30 μl SP600125).The lumbar intrathecal catheters were implanted in L5-6 of rats and CCI models were established as previously described.The thermal and mechanical nociceptive thresholds were assessed by paw withdrawal latency (PWL) to radiant heat and von Frey filaments.The oxycodone,minocycline and SP600125 were administered intrathecally for 3 days before surgery.The spinal cord expression of Ⅰ ba-1,p-c-JNK and CXCL1 proteins assessed by Western blot.Immunofluorescence staining was performed to examine microglia morphology and the number of Ⅰ ba-1 positives cells in dorsal horn of injured spinal cord at 7 days post-IR.Results Compared to sham group,rats in CCI group had significantly lower mechanical and thermal pain thresholds,but higher spinal proteins expression of Ⅰ ba-1,and p-c-JNK and CXCL1 (P ＜0.05).Rats in oxy group,mino group and SP group had significantly higher mechanical and thermal pain thresholds and significantly lower proteins expression of Ⅰ ba-1,p-c-JNK and CXCL1 compared to those in CCI group (at any observed time-point after ligation,but most significantly at 7days,P ＜ 0.05).At the 7days after surgery,microglial cells in CCI group transformed from the ramified shape to amoeboid macrophage-like shape by immunofluorescence staining with the increases of Ⅰ ba-1 positive cells;while the other three groups exhibited hypertrophic morphology with less number Ⅰ ba-1 positive cells (P ＜ 0.05).There were no significant differences between these three groups at any observed time (P ＞ 0.05).Conclusions Intrathecal injection of oxycodone hydrochloride can relieve CCI-induced neuropathic pain by down-regulation microglial c-JNK/CXCL1 signal in spinal cords.Provide new therapeutic targets for clinical treatment of neuropathic pain.
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Objective To investigate the effect of fluvastatin on the expressions of caspase-12,CCAAT/enhancer-binding protein homologous protein(CHOP), and c-Jun N-terminal kinases (JNK) in ischemia-reperfusion brain injury in rats.Methods Forty two rats were randomly divided into sham operation group (6 rats), ischemia-reperfusion (I/R) group (18 rats), and fluvastatin (Flu) group (18 rats).The rats of I/R and Flu groups were molded by modified Longa intraluminal thread, then put to death at 2 h occlusion and 24 h reperfusion point.Expressions of caspase-12, CHOP, and JNK were detected with immunohistochemistry and Western blot.Results Immunohistochemistry and Western blot showed that the expressions of caspase-12, CHOP, and JNK were increased at 24 h reperfusion.Compared to I/R group, the expressions of caspase-12 and CHOP in Flu group were decreased significantly (all P ＜0.01);and the expression of JNK had no difference between I/R and Flu groups(P ＞ 0.05).Conclusions The increased expression of caspase-12, CHOP, and JNK showed that endoplasmic reticulum stress was involved in the pathological process of ischemia-reperfusion brain injury.Fluvastatin could inhibit the expression of caspase12 and CHOP, and could delete endoplasmic reticulum stress (ERS) in ischemia-reperfusion brain injury.