Objective:To investigate the possible mechanism of treadmill exercise(TR)in improving cognitive function of rats with chronic unpredictable mild stress(CUMS)by detecting pathological changes and the expression of sigma-1 receptor(SIR),endoplasmic reticulum stress-related proteins in hippocampus.Methods:30 SD rats were ran-domly allocated into control group(n=10),CUMS group(n=10)and CUMS exercise group(CUMS+TR,n=10).Subsequently,depressive model was established in rats of CUMS group and CUMS+TR group,meanwhile,CUMS+TR group rats were subjected to 4 weeks of moderate intensity treadmill exercise(20 m/min).After the CUMS and tread-mill exercise,the eight-arm radial maze test(RAM)was carried out to evaluate the learning-memory functions.Subse-quently,the pathological changes of neurons in the hippocampus of rats were measured by HE staining,the protein expression of the GRP78,IRE1,XBP1,CHOP,caspase-3 and SIR in the hippocampus were measured by Western blot.Results:Compared with the control group,the time of finishing the eight-arm radial maze prolonged and the num-ber of total memory errors increased(P＜0.05)in the RAM of the CUMS group rats.The morphology and structure of neurons in the hippocampus of CUMS group rats showed obvious pathological changes,the protein expression levels of GRP78,IRE1,XBP1,CHOP and caspase-3 significantly increased and SIR protein expression decreased(P＜0.05)in hippocampus in the CUMS group compared with the control group rats.4-week treadmill exercise significantly im-prove the learning and memory ability and pathological changes of neurons in hippocampus of CUMS+TR group rats.Compared with CUMS group rats,the protein expression levels of GRP78,IRE1,XBP1,CHOP and caspase-3 signifi-cantly decreased,the SIR expression in hippocampus significantly increased in the CUMS+TR group rats(P＜0.05).Conclusion:Treadmill exercise can improve cognitive impairment in CUMS rats,and its mechanism may be related to the up-regulation of SIR expression and the inhibition of ERS-mediated apoptosis pathway in hippocampus.

Objective:To investigate the possible mechanism of treadmill exercise(TR)in improving cognitive function of rats with chronic unpredictable mild stress(CUMS)by detecting pathological changes and the expression of sigma-1 receptor(SIR),endoplasmic reticulum stress-related proteins in hippocampus.Methods:30 SD rats were ran-domly allocated into control group(n=10),CUMS group(n=10)and CUMS exercise group(CUMS+TR,n=10).Subsequently,depressive model was established in rats of CUMS group and CUMS+TR group,meanwhile,CUMS+TR group rats were subjected to 4 weeks of moderate intensity treadmill exercise(20 m/min).After the CUMS and tread-mill exercise,the eight-arm radial maze test(RAM)was carried out to evaluate the learning-memory functions.Subse-quently,the pathological changes of neurons in the hippocampus of rats were measured by HE staining,the protein expression of the GRP78,IRE1,XBP1,CHOP,caspase-3 and SIR in the hippocampus were measured by Western blot.Results:Compared with the control group,the time of finishing the eight-arm radial maze prolonged and the num-ber of total memory errors increased(P＜0.05)in the RAM of the CUMS group rats.The morphology and structure of neurons in the hippocampus of CUMS group rats showed obvious pathological changes,the protein expression levels of GRP78,IRE1,XBP1,CHOP and caspase-3 significantly increased and SIR protein expression decreased(P＜0.05)in hippocampus in the CUMS group compared with the control group rats.4-week treadmill exercise significantly im-prove the learning and memory ability and pathological changes of neurons in hippocampus of CUMS+TR group rats.Compared with CUMS group rats,the protein expression levels of GRP78,IRE1,XBP1,CHOP and caspase-3 signifi-cantly decreased,the SIR expression in hippocampus significantly increased in the CUMS+TR group rats(P＜0.05).Conclusion:Treadmill exercise can improve cognitive impairment in CUMS rats,and its mechanism may be related to the up-regulation of SIR expression and the inhibition of ERS-mediated apoptosis pathway in hippocampus.

Objective To detect the impact of reactive oxygen species ( ROS) on mitochondrial morphology and distri-bution during mitosis.Methods A viral vector in which the fluorescence gene was specifically under the control of mito-chondrial promoter was constructed and confirmed through DNA sequencing and Western blotting.After transfecting HeLa s3 cell with packaged virus, the HeLa s3-COX4tp-EGFP cell line stably expressing the mitochondrial fluorescence signal was obtained.With immunofluorescent staining, the impact of ROS on the morphology and distribution of mitochondria dur-ing mitosis was inspected.Result The cell line constantly expressing mitochondrial fluorescence signals was successfully constructed.Meanwhile,it was found that H2 O2 treatment could significantly change the morphology and distribution of mi-tochondria during mitosis by confocal microscopy.Conclusion Our study demonstrates that ROS can affect the morphology and distribution of mitochondria during mitosis.This research help study the relationship between the mitochondrial function and the regulation of mitosis in the future.

Objective To construct a prokaryotic expression vector pET-22b+with Middle East respiratory syndrome ( MERS) coronavirus nuclocapsid protein( NP) gene and to express and purify N protein.Methods N gene amplified by PCR was inserted into the prokaryotic expression vector pET-22b+.Recombinant plasmid was confirmed using DNA elec-trophoresis and sequencing.NP was expressed in E.coli BL21(DE3) by IPTG induced and purified by cation exchange chromatography using the AKTA purification system.Results The NP gene sequence was proved to be correct by sequen-cing and the protein was expressed in both soluble and insoluble forms in E.coli BL21 ( DE3 ) after IPTG induction.The purity and concentration of recombinant protein was improved obviously by cation exchange chromatography and enrich-ment.Conclusion Recombiant NP of high purity and concentration is purified and will facilitate NP functional research.