Particulate matter (PM), which is a great environmental concern, has been classified as a Group 1 human carcinogen by the International Agency for Research on Cancer (IARC);.Epidemiological and experimental studie...Particulate matter (PM), which is a great environmental concern, has been classified as a Group 1 human carcinogen by the International Agency for Research on Cancer (IARC);.Epidemiological and experimental studies have indicated that chronic exposure to PM, especially PM;(particles with an aerodynamic diameter less than展开更多
Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy(CIMT)involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effe...Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy(CIMT)involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of'learned non-use'and improve limb function after stroke.However,the underlying mechanism of CIMT remains unclear.In the present study,rats were randomly divided into a middle cerebral artery occlusion(model)group,a CIMT+model(CIMT)group,or a sham group.Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups.Compared with the model group,CIMT significantly improved the forelimb functional performance in rats.By western blot assay,the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group,and was similar to sham group levels.These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.展开更多
BACKGROUND: Previous studies have demonstrated that brain-derived neurotrophic factor (BDNF) promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly ...BACKGROUND: Previous studies have demonstrated that brain-derived neurotrophic factor (BDNF) promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE: To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING: A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS: SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid (ATRA) by Sigma-Aldrich, USA. METHODS: SH-SY5Y cells were randomly divided into three groups: blank control [cells were treated in Insulin-Transferrin-Selenium (ITS) solution for 7 days], ATRA (cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days), and BDNF (cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days). The experiment was repeated three times for each group. MAIN OUTCOME MEASURES: mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS: mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group (P 〈 0.05).mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups (P 〈 0.05 or P 〈 0.01). mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1 were significantly decreased in the high-dose BDNF group (P 〈 0.05 or P 〈 0.01). Cyclin-dependent kinase 5 mRNA expression was significantly greater in the low-dose and moderate-dose BDNF groups compared with the ATRA group (P 〈 0.05). The percentage of cells in G1 phase was significantly greater in the different BDNF concentration groups compared with the ATRA and control groups (P 〈 0.01). Moreover, the percentage of cells in S phase was significantly less in the three BDNF groups compared with the ATRA group (P 〈 0.01). However, the percentage of cells in S phase was significantly less in the low-dose and high-dose BDNF groups compared with the control group (P 〈 0.01). CONCLUSION: BDNF enhanced the percentage of cells in G1 phase, but did not alter mRNA expression of cell cycle-related proteins prior to or following G2 phase. These results suggested that BDNF was not a risk factor for inducing apoptosis.展开更多
Cold-inducible RNA-binding protein(CIRP), a key regulatory protein, could be facilitated by mild hypothermia in the brain, heart and liver. This study observed the effects of mild hypothermia at 31 ± 0.5℃ on t...Cold-inducible RNA-binding protein(CIRP), a key regulatory protein, could be facilitated by mild hypothermia in the brain, heart and liver. This study observed the effects of mild hypothermia at 31 ± 0.5℃ on traumatic brain injury in rats. Results demonstrated that mild hypothermia suppressed apoptosis in the cortex, hippocampus and hypothalamus, facilitated CIRP m RNA and protein expression in these regions, especially in the hypothalamus. The anti-apoptotic effect of mild hypothermia disappeared after CIRP silencing. There was no correlation between mitogen-activated extracellular signal-regulated kinase activation and CIRP silencing. CIRP silencing inhibited extracellular signal-regulated kinase-1/2 activation. These indicate that CIRP inhibits apoptosis by affecting extracellular signal-regulated kinase-1/2 activation, and exerts a neuroprotective effect during mild hypothermia for traumatic brain injury.展开更多
基金supported by the National Natural Science Foundation of China[81202231 to LLH]the Medical Scientific Research Funding of Guangdong Province,China[A2018225 to LLH]+1 种基金the College Students Cultivate Special Science and Technology Innovation from Education Department of Guangdong Province,China[pdjh2016a0212]the Project for Creative Talent of Guangdong Education Department[2014KQNCX102]
文摘Particulate matter (PM), which is a great environmental concern, has been classified as a Group 1 human carcinogen by the International Agency for Research on Cancer (IARC);.Epidemiological and experimental studies have indicated that chronic exposure to PM, especially PM;(particles with an aerodynamic diameter less than
基金supported by grants from the National Natural Science Foundation of China,No.81372119a grant from the Science and Technology Commission of Shanghai Municipality,No.12ZR1404000
文摘Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy(CIMT)involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of'learned non-use'and improve limb function after stroke.However,the underlying mechanism of CIMT remains unclear.In the present study,rats were randomly divided into a middle cerebral artery occlusion(model)group,a CIMT+model(CIMT)group,or a sham group.Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups.Compared with the model group,CIMT significantly improved the forelimb functional performance in rats.By western blot assay,the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group,and was similar to sham group levels.These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.
文摘BACKGROUND: Previous studies have demonstrated that brain-derived neurotrophic factor (BDNF) promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE: To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING: A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS: SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid (ATRA) by Sigma-Aldrich, USA. METHODS: SH-SY5Y cells were randomly divided into three groups: blank control [cells were treated in Insulin-Transferrin-Selenium (ITS) solution for 7 days], ATRA (cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days), and BDNF (cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days). The experiment was repeated three times for each group. MAIN OUTCOME MEASURES: mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS: mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group (P 〈 0.05).mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups (P 〈 0.05 or P 〈 0.01). mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1 were significantly decreased in the high-dose BDNF group (P 〈 0.05 or P 〈 0.01). Cyclin-dependent kinase 5 mRNA expression was significantly greater in the low-dose and moderate-dose BDNF groups compared with the ATRA group (P 〈 0.05). The percentage of cells in G1 phase was significantly greater in the different BDNF concentration groups compared with the ATRA and control groups (P 〈 0.01). Moreover, the percentage of cells in S phase was significantly less in the three BDNF groups compared with the ATRA group (P 〈 0.01). However, the percentage of cells in S phase was significantly less in the low-dose and high-dose BDNF groups compared with the control group (P 〈 0.01). CONCLUSION: BDNF enhanced the percentage of cells in G1 phase, but did not alter mRNA expression of cell cycle-related proteins prior to or following G2 phase. These results suggested that BDNF was not a risk factor for inducing apoptosis.
基金supported by the National Natural Science Foundation of China,No.81303091
文摘Cold-inducible RNA-binding protein(CIRP), a key regulatory protein, could be facilitated by mild hypothermia in the brain, heart and liver. This study observed the effects of mild hypothermia at 31 ± 0.5℃ on traumatic brain injury in rats. Results demonstrated that mild hypothermia suppressed apoptosis in the cortex, hippocampus and hypothalamus, facilitated CIRP m RNA and protein expression in these regions, especially in the hypothalamus. The anti-apoptotic effect of mild hypothermia disappeared after CIRP silencing. There was no correlation between mitogen-activated extracellular signal-regulated kinase activation and CIRP silencing. CIRP silencing inhibited extracellular signal-regulated kinase-1/2 activation. These indicate that CIRP inhibits apoptosis by affecting extracellular signal-regulated kinase-1/2 activation, and exerts a neuroprotective effect during mild hypothermia for traumatic brain injury.
文摘目的:研究P38丝裂原活化蛋白激酶(mitogenactivated protein kinase,MAPK)通路在急性重症胰腺炎(severe acute pancreatitis,SAP)大鼠模型海马神经元中对诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和前列腺素E2(prostaglandin E2,PGE2)的作用.方法:将60只SD大鼠随机分为对照组、SAP模型组(模型组)、抑制剂组(P38MAPK通路抑制剂SB203580).Nissl染色、免疫组织化学显色、免疫印迹法检测大鼠海马CA1区iNOS、PGE2和p-P38表达的变化;应用透射电镜观察胰腺组织超微结构的变化.结果:与对照组相比,SAP模型组海马CA1区p-P38(20.4±2.2 vs 2.1±1.3)、i NOS(33.6±4.4 vs 3.7±0.4)、PGE2(34.7±4.0 vs 2.4±1.0)阳性神经元的数量显著增加(P<0.05);给予S B203580后,抑制剂组海马C A1区p-P3 8(1 2.8±0.7)、iNOS(1 4.4±4.9)、P G E2(18.3±0.5)阳性神经元的数量明显减少(P<0.05).模型组胰腺细胞粗面内质网脱颗粒,线粒体水肿扩张,抑制剂组上述改变明显减轻.结论:P38丝裂原活化蛋白激酶通路对SAP大鼠模型海马i NOS和PGE2表达可能起调控作用,抑制该通路对SAP大鼠具有神经保护作用.