BACKGROUND: Previous studies have shown that transforming growth factor-beta 1 (TGF-beta 1) is the most potent means of stimulating liver fibrogenesis by myofibroblast-like cells derived from hepatic stellate cells. T...BACKGROUND: Previous studies have shown that transforming growth factor-beta 1 (TGF-beta 1) is the most potent means of stimulating liver fibrogenesis by myofibroblast-like cells derived from hepatic stellate cells. Thus, TGF-beta 1 could be a target for treating hepatic fibrosis. This study aimed to investigate the inhibitory effects of specific TGF-beta 1 small interference RNA (siRNA) on immune hepatic fibrosis induced by Concanavalin A (Con A) in mice. METHODS: Three short hairpin RNAs targeting different positions of TGF-beta 1 were designed and cloned to the plasmid pGenesil-1 to obtain three recombinant expression vectors (pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 and pGenesil-TGF-beta 1-m3). Thirty male Kunming mice were randomly divided into 6 groups: normal, model, control, and three treatment groups. The immune hepatic fibrosis models were constructed by injecting Con A via the tail vein at 8 mg/kg per week for 6 weeks. At weeks 2, 4 and 6, pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 or pGenesi1-TGF-beta 1-m3 was injected by a hydrodynamics-based transfection method via the tail vein at 0.8 ml/10 g within 24 hours after injection of Con A in each of the three treatment groups. The mice in the control group were injected with control plasmid pGenesil-HK at the same dose. All mice were sacrificed at week 7. The levels of hydroxyproline in liver tissue were determined by biochemistry. Liver histopathology was assessed by Van Gieson staining. The expression levels and localization of TGF-beta 1, Smad3, and Smad7 in liver tissue were detected by immunohistochemistry. The expression of TGF-beta 1, Smad3, Smad7 and alpha-smooth muscle actin (alpha-SMA) mRNAs in the liver were assessed by semi-quantitative RT-PCR. RESULTS: The levels of hydroxyproline in the liver tissue of the treatment groups were lower than those of the model group (P<0.01). Histopathologic assay showed that liver fibrogenesis was clearly improved in the treatment groups compared with the model group. The expression levels of TGF-beta 1 and Smad3 of liver tissue were also markedly lower in the treatment groups than in the model group (P<0.01), while the levels of Smad7 were higher in the treatment groups than in the model group (P<0.01). RT-PCR further showed that the expression of TGF-beta 1, Smad3 and alpha-SMA mRNA was significantly inhibited in the treatment groups compared with the model group, while the levels of Smad7 were increased. There was no difference in the above parameters among the three treatment groups or between the control and model groups (P>0.05), but the inhibitory effect of pGenesil-TGF-beta 1-ml was the highest among the treatment groups. CONCLUSIONS: Specific siRNA targeting of TGF-beta 1 markedly inhibited the fibrogenesis of immune hepatic fibrosis induced by Con A in mice. The anti-fibrosis mechanisms of siRNAs may be associated with the down-regulation of TGF-beta 1, Smad3 and alpha-SMA expression and up-regulation of Smad7 expression in liver tissue, which resulted in suppressing the activation of hepatic stellate cells. (Hepatobiliary Pancreat Dis Int 2009; 8: 300-308)展开更多
BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the...BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.展开更多
The expression of the anti-apoptotic molecules Bcl-2 and transforming growth factor-beta 1 is known to confer protective effects on the cerebral ischemia-reperfusion injury.The current study investigated the expressio...The expression of the anti-apoptotic molecules Bcl-2 and transforming growth factor-beta 1 is known to confer protective effects on the cerebral ischemia-reperfusion injury.The current study investigated the expression levels of Bcl-2 and transforming growth factor-beta 1 in response to multiple pre-ischemia electro-acupuncture at acupoints Zusanli(ST36)and Fengchi(GB20) stimulation.Rats were divided into five groups:uninjured,control,non-acupoint,GB20 and ST36. Rats in the non-acupoint,GB20 and ST36 groups received 30 minutes(3 times or 18 times)of electro-acupuncture stimulation before experimental cerebral ischemia was induced.Bcl-2 and transforming growth factor-beta 1 were found to be significantly increased in the ST36 groups with either 3 or 18 electro-acupuncture treatments(P〈0.05).The production was higher with 18 electro-acupuncture treatments in the ST36 groups(P〈0.05).In the GB20 groups,significant increase was only observed in transforming growth factor-beta 1 with 18 electro-acupuncture treatments(P〈0.05).No significant elevation of the level of transforming growth factor-beta 1 was observed in the non-acupoint groups.However,the production of Bcl-2 increased with 18 treatments in the non-acupoint groups(P〈0.05).The data suggest that multiple pre-ischemia electro-acupuncture at ST36 was effective in conferring neuroprotective effect on the brain by means of upregulation of Bcl-2 and transforming growth factor-beta 1 and the effect was increase with the number of treatment.展开更多
BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, an...BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression.展开更多
文摘BACKGROUND: Previous studies have shown that transforming growth factor-beta 1 (TGF-beta 1) is the most potent means of stimulating liver fibrogenesis by myofibroblast-like cells derived from hepatic stellate cells. Thus, TGF-beta 1 could be a target for treating hepatic fibrosis. This study aimed to investigate the inhibitory effects of specific TGF-beta 1 small interference RNA (siRNA) on immune hepatic fibrosis induced by Concanavalin A (Con A) in mice. METHODS: Three short hairpin RNAs targeting different positions of TGF-beta 1 were designed and cloned to the plasmid pGenesil-1 to obtain three recombinant expression vectors (pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 and pGenesil-TGF-beta 1-m3). Thirty male Kunming mice were randomly divided into 6 groups: normal, model, control, and three treatment groups. The immune hepatic fibrosis models were constructed by injecting Con A via the tail vein at 8 mg/kg per week for 6 weeks. At weeks 2, 4 and 6, pGenesil-TGF-beta 1-ml, pGenesil-TGF-beta 1-m2 or pGenesi1-TGF-beta 1-m3 was injected by a hydrodynamics-based transfection method via the tail vein at 0.8 ml/10 g within 24 hours after injection of Con A in each of the three treatment groups. The mice in the control group were injected with control plasmid pGenesil-HK at the same dose. All mice were sacrificed at week 7. The levels of hydroxyproline in liver tissue were determined by biochemistry. Liver histopathology was assessed by Van Gieson staining. The expression levels and localization of TGF-beta 1, Smad3, and Smad7 in liver tissue were detected by immunohistochemistry. The expression of TGF-beta 1, Smad3, Smad7 and alpha-smooth muscle actin (alpha-SMA) mRNAs in the liver were assessed by semi-quantitative RT-PCR. RESULTS: The levels of hydroxyproline in the liver tissue of the treatment groups were lower than those of the model group (P<0.01). Histopathologic assay showed that liver fibrogenesis was clearly improved in the treatment groups compared with the model group. The expression levels of TGF-beta 1 and Smad3 of liver tissue were also markedly lower in the treatment groups than in the model group (P<0.01), while the levels of Smad7 were higher in the treatment groups than in the model group (P<0.01). RT-PCR further showed that the expression of TGF-beta 1, Smad3 and alpha-SMA mRNA was significantly inhibited in the treatment groups compared with the model group, while the levels of Smad7 were increased. There was no difference in the above parameters among the three treatment groups or between the control and model groups (P>0.05), but the inhibitory effect of pGenesil-TGF-beta 1-ml was the highest among the treatment groups. CONCLUSIONS: Specific siRNA targeting of TGF-beta 1 markedly inhibited the fibrogenesis of immune hepatic fibrosis induced by Con A in mice. The anti-fibrosis mechanisms of siRNAs may be associated with the down-regulation of TGF-beta 1, Smad3 and alpha-SMA expression and up-regulation of Smad7 expression in liver tissue, which resulted in suppressing the activation of hepatic stellate cells. (Hepatobiliary Pancreat Dis Int 2009; 8: 300-308)
基金supported by grants from the Natural Science Foundation of Jiangsu Province,China (No. BK2006241)the Foundation for Talents in Six Fields of Jiangsu Province (No. 07-B-038)
文摘BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.
基金supported by the Niche Area Grant of the Hong Kong Polytechnic University through the projects JBB71 and BB8V
文摘The expression of the anti-apoptotic molecules Bcl-2 and transforming growth factor-beta 1 is known to confer protective effects on the cerebral ischemia-reperfusion injury.The current study investigated the expression levels of Bcl-2 and transforming growth factor-beta 1 in response to multiple pre-ischemia electro-acupuncture at acupoints Zusanli(ST36)and Fengchi(GB20) stimulation.Rats were divided into five groups:uninjured,control,non-acupoint,GB20 and ST36. Rats in the non-acupoint,GB20 and ST36 groups received 30 minutes(3 times or 18 times)of electro-acupuncture stimulation before experimental cerebral ischemia was induced.Bcl-2 and transforming growth factor-beta 1 were found to be significantly increased in the ST36 groups with either 3 or 18 electro-acupuncture treatments(P〈0.05).The production was higher with 18 electro-acupuncture treatments in the ST36 groups(P〈0.05).In the GB20 groups,significant increase was only observed in transforming growth factor-beta 1 with 18 electro-acupuncture treatments(P〈0.05).No significant elevation of the level of transforming growth factor-beta 1 was observed in the non-acupoint groups.However,the production of Bcl-2 increased with 18 treatments in the non-acupoint groups(P〈0.05).The data suggest that multiple pre-ischemia electro-acupuncture at ST36 was effective in conferring neuroprotective effect on the brain by means of upregulation of Bcl-2 and transforming growth factor-beta 1 and the effect was increase with the number of treatment.
基金Supported by:Scientific and Technological Foundation of the National Administration of Traditional Chinese Medicine of China,No.02-03LP41the Scientific and Technological Key Project of Guangdong Province,No. 2006B35630007
文摘BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression.