BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neur...BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.展开更多
To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein express...To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.展开更多
Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten (PTEN) gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely ...Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten (PTEN) gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene (Ad-PTEN) was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.展开更多
Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is...Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods: Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells (HUVEC) were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α (TN F-α) treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results: The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3' untranslated region site, Conclusion: MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.展开更多
BACKGROUND The modified Xiaoyao San(MXS)formula is an adjuvant drug recommended by the National Health Commission of China for the treatment of liver cancer,which has the effect of preventing postoperative recurrence ...BACKGROUND The modified Xiaoyao San(MXS)formula is an adjuvant drug recommended by the National Health Commission of China for the treatment of liver cancer,which has the effect of preventing postoperative recurrence and metastasis of hepatocellular carcinoma and prolonging patient survival.However,the molecular mechanisms underlying that remain unclear.AIM To investigate the role and mechanisms of MXS in ameliorating hepatic injury,steatosis and inflammation.METHODS A choline-deficient/high-fat diet-induced rat nonalcoholic steatohepatitis(NASH)model was used to examine the effects of MXS on lipid accumulation in primary hepatocytes.Liver tissues were collected for western blotting and immunohisto chemistry(IHC)assays.Lipid accumulation and hepatic fibrosis were detected using oil red staining and Sirius red staining.The serum samples were collected for biochemical assays and NMR-based metabonomics analysis.The inflammation/lipid metabolism-related signaling and regulators in liver tissues were also detected to reveal the molecular mechanisms of MXS against NASH.RESULTS MXS showed a significant decrease in lipid accumulation and inflammatory response in hepatocytes under metabolic stress.The western blotting and IHC results indicated that MXS activated AMPK pathway but inhibited the expression of key regulators related to lipid accumulation,inflammation and hepatic fibrosis in the pathogenesis of NASH.The metabonomics analysis systemically indicated that the arachidonic acid metabolism and steroid hormone synthesis are the two main target metabolic pathways for MXS to ameliorate liver inflammation and hepatic steatosis.Mechanistically,we found that MXS protected against NASH by attenuating the sex hormone-related metabolism,especially the metabolism of male hormones.CONCLUSION MXS ameliorates inflammation and hepatic steatosis of NASH by inhibiting the metabolism of male hormones.Targeting male hormone related metabolic pathways may be the potential therapeutic approach for NASH.展开更多
基金the Natural Science Foundation of Jiangsu Province, No. BK2004048the Social Development and Technology Plan of Nantong City, No. K2008009
文摘BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.
文摘To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.
文摘Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten (PTEN) gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene (Ad-PTEN) was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.
基金This research was funded by the National Natural Science Foundation of China (NSFC)
文摘Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods: Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells (HUVEC) were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α (TN F-α) treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results: The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3' untranslated region site, Conclusion: MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.
基金Supported by Chongqing Fundamental Research Funds,No.jbky20210001Key Programs of Technological Innovation and Application Development of Chongqing,China,No.cstc2021jscx-dxwtBX0016+2 种基金Natural Science Foundation of Chongqing,No.cstc2021jcyjmsxmX0793Science and Technology Project in Social Livelihood of Bishan District,Chongqing,China,No.BSKJ0078 and No.BSKJ0075Performance Incentive-oriented Project of Chongqing,No.jxjl20220007。
文摘BACKGROUND The modified Xiaoyao San(MXS)formula is an adjuvant drug recommended by the National Health Commission of China for the treatment of liver cancer,which has the effect of preventing postoperative recurrence and metastasis of hepatocellular carcinoma and prolonging patient survival.However,the molecular mechanisms underlying that remain unclear.AIM To investigate the role and mechanisms of MXS in ameliorating hepatic injury,steatosis and inflammation.METHODS A choline-deficient/high-fat diet-induced rat nonalcoholic steatohepatitis(NASH)model was used to examine the effects of MXS on lipid accumulation in primary hepatocytes.Liver tissues were collected for western blotting and immunohisto chemistry(IHC)assays.Lipid accumulation and hepatic fibrosis were detected using oil red staining and Sirius red staining.The serum samples were collected for biochemical assays and NMR-based metabonomics analysis.The inflammation/lipid metabolism-related signaling and regulators in liver tissues were also detected to reveal the molecular mechanisms of MXS against NASH.RESULTS MXS showed a significant decrease in lipid accumulation and inflammatory response in hepatocytes under metabolic stress.The western blotting and IHC results indicated that MXS activated AMPK pathway but inhibited the expression of key regulators related to lipid accumulation,inflammation and hepatic fibrosis in the pathogenesis of NASH.The metabonomics analysis systemically indicated that the arachidonic acid metabolism and steroid hormone synthesis are the two main target metabolic pathways for MXS to ameliorate liver inflammation and hepatic steatosis.Mechanistically,we found that MXS protected against NASH by attenuating the sex hormone-related metabolism,especially the metabolism of male hormones.CONCLUSION MXS ameliorates inflammation and hepatic steatosis of NASH by inhibiting the metabolism of male hormones.Targeting male hormone related metabolic pathways may be the potential therapeutic approach for NASH.