Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a...Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.展开更多
Bronchial asthma is a common chronic airway inflammatory disease. Asthma is associated with high mortality, especially in the elderly patients. Repeated exacerbations cause disease progression. Therefore, identifying ...Bronchial asthma is a common chronic airway inflammatory disease. Asthma is associated with high mortality, especially in the elderly patients. Repeated exacerbations cause disease progression. Therefore, identifying the onset of acute elderly asthma as soon as possible and giving the effective treatment is crucial to improve the prognosis. This study was to investigate the significance of fractional exhaled nitric oxide （FeNO） combined with serum procalcitonin （PCT） and C-reactive protein （CRP） in the evaluation of elderly asthma. A total of 120 elderly patients with an acute attack of asthma from July, 2010 to May, 2012 were studied. On presentation, FeNO, serum PCT and CRP concentrations were measured and sputum culture was also performed. The elderly patients were re-evaluated when they had returned to their stable clinical state. The elderly patients were classified into two groups： positive bac- terial culture group （A） and negative bacterial culture group （B）. The results showed that： （1） In patients with an acute exacerbation of asthma, 48 （40%） patients had positive sputum bacterial culture and 72 （60%） had negative sputum bacterial culture. （2） The levels of FeNO in patients with acute exacerbation of asthma were significantly higher than in those with no acute exacerbation state （63.8±24.6 vs. 19±6.5 ppb, P〈0.05）. There was no significant difference in FeNO between group A and group B （P〉0.05）. （3） The levels of PCT and CRP in group A patients with an acute exacerbation of asthma were significantly higher （P〈0.05） than in group B （for PCT： 27.46±9.32 vs. 7.85±3.52 ng/mL; for CRP： 51.25±11.46 vs. 17.11±5.87 mg/L, respectively）. When they had returned to stable clinical state, the levels of PCT and CRP in group A were decreased significantly （P〈0.05）, and those in group B had no significant change （P〉0.05） when compared with the exacerbation group. There were no significant differences in the levels of PCT and CRP between the two groups in non-acute exacerbation state （/9〉0.05）. These results suggest that the increase in FeNO indicates the acute exacerbation of asthma, and the elevation of serum PCT and CRP levels may be associated with bacterial infection.展开更多
Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of ather...Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of atherosclerosis by increasing endothelial adhesiveness.Here,we sought to investigate whether CTRP1 also influences vascular dilatory functions.展开更多
Recent studies have shown that nitric oxide （NO） can induce migraine attacks at three possible sites of action： nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies ...Recent studies have shown that nitric oxide （NO） can induce migraine attacks at three possible sites of action： nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies have focused on the former two sites of action. Several experiments using exogenic NO donors have suggested that nitroglycerin may induce migraine via central mechanisms. However, few studies have investigated the source of the NO involved in the central mechanisms of migraine. The present study used a cat model of migraine to represent migraine attacks in humans. We performed immunochemical staining of successive frozen sections of the brainstem and upper cervical spinal cord, and then used c-Fos protein expression to label nerve cell activation. We observed the effects of N^ω-nitro-L-arginine methyl ester （L-NAME）, a non-selective nitric oxide synthase （NOS） inhibitor, and 7-nitroindozole （7-NI）, a selective neuronal NOS inhibitor, on c-Fos and nNOS expression, which were induced by electrical stimulation to the dura mater near the superior sagittal sinus. The results demonstrated that c-Fos or nNOS immunoreactive cells was concentrated in the superficial layers （laminae Ⅰ and Ⅱ） of the spinal nucleus of trigeminal nerve. L-NAME and 7-NI pre-treatment significantly decreased c-Fos and neurogenic NOS expression; and there was a significant linear correlation between c-Fos and NOS expression （r = 0.858 2, P 〈 0.01）. These findings suggest that neurogenic NO could facilitate migraine nociceptive transmission to second-order neurons of the trigeminal nerve. However, L-NAME and 7-NI may block the activation of neurons in the spinal nucleus of the trigeminal nerve by inhibiting NO synthesis, and thereby attenuate acute migraine attacks.展开更多
The depression of cardiac contractility induced by space microgravity is an important issue of aerospace medicine research, while its precise mechanism is still unknown. In the present study, we explored effects of si...The depression of cardiac contractility induced by space microgravity is an important issue of aerospace medicine research, while its precise mechanism is still unknown. In the present study, we explored effects of simulated microgravity on nitric oxide (NO) level, inducible nitric oxide synthase (iNOS) expression and related regulative mechanism using electron spin resonance (ESR) spectroscopy, immunocytochemistry and in situ hybridization. We found a remarkable in-crease of NO level and up-regulation of iNOS and iNOS mRNA expression in rat cardiac myocytes under simulated microgravity. Staurosporine (a nonselective protein kinase inhibitor), calphostin C (a selective protein kinase C inhibitor), partially inhibited the effect of simulated microgravity. Thus regulative effect of simulated microgravity on iNOS expression is mediated at least partially via activation of protein kinase C. These results indicate that NO system in cardiac myocytes is sensi-tive to simulated microgravity and may play an important role in the depression of cardiac contrac-tility induced by simulated microgravity.展开更多
Background C-Jun N-terminal kinase （JNK） signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The...Background C-Jun N-terminal kinase （JNK） signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether the activation of JNK1/2 is associated with the production of endogenous nitric oxide （NO）. Methods Ischemia and reperfusion （I/R） was induced by cerebral four-vessel occlusion. Sprague-Dawley （SD） rats were divided into 6 groups： sham group, I/R group, neuronal nitric oxide synthase （nNOS） inhibitor （7-nitroindazole, 7-NI） given group, inducible nitric oxide synthase （iNOS） inhibitor （2-amino-5,6-dihydro-methylthiazine, AMT） given group, sodium chloride control group, and 1% dimethyl sulfoxide （DMSO） control group. The levels of protein expression and phospho-JNK1/2 were detected by Western blotting and the survival hippocampus neurons in CA1 zone were observed by cresyl violet staining. Results The study illustrated two peaks of JNK1/2 activation occurred at 30 minutes and 3 days during reperfusion. 7-NI inhibited JNK1/2 activation during the early reperfusion, whereas AMT preferably attenuated JNK1/2 activation during the later reperfusion. Administration of 7-NI and AMT can decrease I/R-induced neuronal loss in hippocampal CA1 region. Conclusion JNK1/2 activation is associated with endogenous NO in response to ischemic insult.展开更多
基金supported by the Natural Nature Science Foundation of China,Nos.82030071,81874004the Science and Technology Major Project of Changsha,No.kh2103008(all to JZH).
文摘Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.
基金supported by Fundation of Henan Provincial Medical Science and Technology Research(No.201003098)
文摘Bronchial asthma is a common chronic airway inflammatory disease. Asthma is associated with high mortality, especially in the elderly patients. Repeated exacerbations cause disease progression. Therefore, identifying the onset of acute elderly asthma as soon as possible and giving the effective treatment is crucial to improve the prognosis. This study was to investigate the significance of fractional exhaled nitric oxide （FeNO） combined with serum procalcitonin （PCT） and C-reactive protein （CRP） in the evaluation of elderly asthma. A total of 120 elderly patients with an acute attack of asthma from July, 2010 to May, 2012 were studied. On presentation, FeNO, serum PCT and CRP concentrations were measured and sputum culture was also performed. The elderly patients were re-evaluated when they had returned to their stable clinical state. The elderly patients were classified into two groups： positive bac- terial culture group （A） and negative bacterial culture group （B）. The results showed that： （1） In patients with an acute exacerbation of asthma, 48 （40%） patients had positive sputum bacterial culture and 72 （60%） had negative sputum bacterial culture. （2） The levels of FeNO in patients with acute exacerbation of asthma were significantly higher than in those with no acute exacerbation state （63.8±24.6 vs. 19±6.5 ppb, P〈0.05）. There was no significant difference in FeNO between group A and group B （P〉0.05）. （3） The levels of PCT and CRP in group A patients with an acute exacerbation of asthma were significantly higher （P〈0.05） than in group B （for PCT： 27.46±9.32 vs. 7.85±3.52 ng/mL; for CRP： 51.25±11.46 vs. 17.11±5.87 mg/L, respectively）. When they had returned to stable clinical state, the levels of PCT and CRP in group A were decreased significantly （P〈0.05）, and those in group B had no significant change （P〉0.05） when compared with the exacerbation group. There were no significant differences in the levels of PCT and CRP between the two groups in non-acute exacerbation state （/9〉0.05）. These results suggest that the increase in FeNO indicates the acute exacerbation of asthma, and the elevation of serum PCT and CRP levels may be associated with bacterial infection.
文摘Objective C1q/TNF-related protein(CTRP)1 was initiallyidentified as a paralog of adiponectin based on the similarity in C1q domain of these two proteins.Previously,we showed that CTRP1promotes the development of atherosclerosis by increasing endothelial adhesiveness.Here,we sought to investigate whether CTRP1 also influences vascular dilatory functions.
文摘Recent studies have shown that nitric oxide （NO） can induce migraine attacks at three possible sites of action： nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies have focused on the former two sites of action. Several experiments using exogenic NO donors have suggested that nitroglycerin may induce migraine via central mechanisms. However, few studies have investigated the source of the NO involved in the central mechanisms of migraine. The present study used a cat model of migraine to represent migraine attacks in humans. We performed immunochemical staining of successive frozen sections of the brainstem and upper cervical spinal cord, and then used c-Fos protein expression to label nerve cell activation. We observed the effects of N^ω-nitro-L-arginine methyl ester （L-NAME）, a non-selective nitric oxide synthase （NOS） inhibitor, and 7-nitroindozole （7-NI）, a selective neuronal NOS inhibitor, on c-Fos and nNOS expression, which were induced by electrical stimulation to the dura mater near the superior sagittal sinus. The results demonstrated that c-Fos or nNOS immunoreactive cells was concentrated in the superficial layers （laminae Ⅰ and Ⅱ） of the spinal nucleus of trigeminal nerve. L-NAME and 7-NI pre-treatment significantly decreased c-Fos and neurogenic NOS expression; and there was a significant linear correlation between c-Fos and NOS expression （r = 0.858 2, P 〈 0.01）. These findings suggest that neurogenic NO could facilitate migraine nociceptive transmission to second-order neurons of the trigeminal nerve. However, L-NAME and 7-NI may block the activation of neurons in the spinal nucleus of the trigeminal nerve by inhibiting NO synthesis, and thereby attenuate acute migraine attacks.
基金supported by National Plan of High-Tech Research and Development(863-2-2-2-4).
文摘The depression of cardiac contractility induced by space microgravity is an important issue of aerospace medicine research, while its precise mechanism is still unknown. In the present study, we explored effects of simulated microgravity on nitric oxide (NO) level, inducible nitric oxide synthase (iNOS) expression and related regulative mechanism using electron spin resonance (ESR) spectroscopy, immunocytochemistry and in situ hybridization. We found a remarkable in-crease of NO level and up-regulation of iNOS and iNOS mRNA expression in rat cardiac myocytes under simulated microgravity. Staurosporine (a nonselective protein kinase inhibitor), calphostin C (a selective protein kinase C inhibitor), partially inhibited the effect of simulated microgravity. Thus regulative effect of simulated microgravity on iNOS expression is mediated at least partially via activation of protein kinase C. These results indicate that NO system in cardiac myocytes is sensi-tive to simulated microgravity and may play an important role in the depression of cardiac contrac-tility induced by simulated microgravity.
文摘目的探讨新生儿持续肺动脉高压(persistent pulmonary hypertension of newborn,PPHN)患儿血清人CXC型趋化因子配体8(C-X-C motif chemokine ligand 8,CXCL8)、CXCL12与一氧化氮吸入治疗临床转归的关系。方法选择2021-08/2023-05月作者医院收治并给予一氧化氮吸入治疗的PPHN患儿135例为研究对象。根据患儿出院时临床转归结局分为死亡组(n=32)和存活组(n=103)。比较两组PPHN患儿血清CXCL8、CXCL12水平。单因素及多因素Logistic回归模型分析接受一氧化氮吸入治疗PPHN患儿临床转归的影响因素。受试者工作特征(receiver operating characteristic,ROC)曲线分析血清CXCL8、CXCL12对接受一氧化氮吸入治疗PPHN患儿临床转归的预测价值。结果死亡组患儿血清CXCL8、CXCL12水平显著高于存活组(P均<0.05)。多因素Logsitic回归分析结果显示,血清CXCL8水平升高、血清CXCL12水平升高、早产、出生时Apgar评分0~3分、合并并发症是接受一氧化氮吸入治疗的PPHN患儿死亡的危险因素,肺表面活性物质应用、吸入一氧化氮早期反应则是保护因素(P<0.05)。ROC曲线分析结果显示,血清CXCL8、CXCL12联合检测对接受一氧化氮吸入治疗的PPHN患儿死亡预测的曲线下面积(area under the curve,AUC)为0.828,大于血清CXCL8、CXCL12单独检测(AUC分别为0.762、0.714)。结论PPHN患儿血清CXCL8、CXCL12水平升高与接受一氧化氮治疗的不良临床转归有关,且CXCL8、CXCL12水平升高是PPHN患儿死亡的危险因素。CXCL8、CXCL12联合检测对接受一氧化氮治疗PPHN患儿死亡具有较高的预测价值。
基金This work was supported by a grant from the Project of China Postdoctoral Science Foundation （No. 20100480568）.
文摘Background C-Jun N-terminal kinase （JNK） signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether the activation of JNK1/2 is associated with the production of endogenous nitric oxide （NO）. Methods Ischemia and reperfusion （I/R） was induced by cerebral four-vessel occlusion. Sprague-Dawley （SD） rats were divided into 6 groups： sham group, I/R group, neuronal nitric oxide synthase （nNOS） inhibitor （7-nitroindazole, 7-NI） given group, inducible nitric oxide synthase （iNOS） inhibitor （2-amino-5,6-dihydro-methylthiazine, AMT） given group, sodium chloride control group, and 1% dimethyl sulfoxide （DMSO） control group. The levels of protein expression and phospho-JNK1/2 were detected by Western blotting and the survival hippocampus neurons in CA1 zone were observed by cresyl violet staining. Results The study illustrated two peaks of JNK1/2 activation occurred at 30 minutes and 3 days during reperfusion. 7-NI inhibited JNK1/2 activation during the early reperfusion, whereas AMT preferably attenuated JNK1/2 activation during the later reperfusion. Administration of 7-NI and AMT can decrease I/R-induced neuronal loss in hippocampal CA1 region. Conclusion JNK1/2 activation is associated with endogenous NO in response to ischemic insult.
