The changes of proto-oncogene c-fos and c-jun mRNA expression in angiotensin Ⅱ (AngⅡ)-induced hypertrophy and effects of sodium tanshinone ⅡA sulfonate (STS) in the primary culture of neonatal rat cardiomyocyte...The changes of proto-oncogene c-fos and c-jun mRNA expression in angiotensin Ⅱ (AngⅡ)-induced hypertrophy and effects of sodium tanshinone ⅡA sulfonate (STS) in the primary culture of neonatal rat cardiomyocytes were investigated. Twelve neonatal clean grade Wistar rats were selected. The cardiomyocytes were isolated, cultured and divided according to different treatments in the medium. The cardiomyocyte size was determined by phase contrast microscope, and the rate of protein synthesis was measured by [3H]-Leucine incorporation. The c-fos and c-jun mRNA expression in cardiomyocytes was detected by reverse transcription polymerase chain reaction (RT-PCR). It was found after cardiomyocytes were treated with AngⅡ for 30 min, the c-fos and c-jun mRNA expression in cardiomyocytes was increased significantly (P〈0.01). After treatment with AngⅡ for 24 h, the rate of protein synthesis in AngⅡ group was significantly increased as compared with control group (P〈0.01). After treatment with AngⅡ for 7 days, the size of cardiomyocytes in AngⅡ group was increased obviously as compared with control group (P〈0.05). After pretreatment with STS or Valsartan before AngⅡ treatment, both of them could inhibit the above effects of AngⅡ (P〈0.05 or P〈0.01). It was suggested that STS could ameliorate AngⅡ-induced cardiomyocyte hy- pertrophy by inhibiting c-fos and c-jun mRNA expression and reducing protein synthesis rate of cardiomyocytes.展开更多
Previous work from this laboratory has demonstrated that the addition of angiotensin(Aug)Ⅱresults in the rapid transcriptional activation of early growth response gene c-fos.Blockage of this increase completely inhib...Previous work from this laboratory has demonstrated that the addition of angiotensin(Aug)Ⅱresults in the rapid transcriptional activation of early growth response gene c-fos.Blockage of this increase completely inhibits the Aug Ⅱinduced increase in vascular smooth muscle cell(VSMC)growth.To explore the molecular mechanism responsible for the induction of c-fos in VSMC,a series of constructs containing portions of c-fos promoter linked to the reporter gene chloramphenicol acetyltransferase(CAT)were used in transient transfection assays.When a construct containing both the well described serum response element(SRE)and the cyclic AMP response element(CRE)was used,no endogenous CAT activity was observed in serum starved cells.The addition of either Ang Ⅱor serum resulted in a marked increase in CAT activity.Mutations in either the SRE or CRE alone which have been demonstrated to inactivate these elements in number of cell types had no effect on c-fos inducibility by either Angll or serum. In contrast,if both elements were mutated in the same construct,inducibility was reduced by 75 % ̄80%.Using a construct in which the SRE has been deleted,a mutation in the CRE completely abolished induction of c-fos by either Aug Ⅱor serum. Mobility shift assays demonstrated that tow proteins bind specifically to the SRE and three proteins to CRE. These data demonstrate that the induction of c-fos in VSMC's can be mediated by two distinct enhancer elements each of which can act independently. Future research will be aimed at identifying the proteins that interact with these elemetns delineating the mechanisms by which Ang Ⅱstimulates their activity.展开更多
Train drivers are engaged in high-stress job. It may induce sleep, fatigue, and alertness loss at work, and endanger public safety. It’s unclear that cytokines of train driver would be influenced by their job. The re...Train drivers are engaged in high-stress job. It may induce sleep, fatigue, and alertness loss at work, and endanger public safety. It’s unclear that cytokines of train driver would be influenced by their job. The research considers the hypothesis that stressful professions, such as train driver, influence the body’s immune system through the long-time and high-pressure working, and change production of neuro-immune factors. Using enzyme linked immunosorbent assay (ELISA), several neuro-immune factors were assayed among train drivers (N = 82) and health blood donors (N = 80) enrolled in the Yunnan Collaborative Innovation Center for Public Health and Disease Control. The concentrations of angiotensin, C-reactive protein (CRP), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-α) were determined. Kruskal-Wallis test and Dunn’s multiple comparisons test were performed for overall comparison between groups and for pairwise comparison, respectively. Statistical significance level was set at P < 0.05. The profession of train driving was not associated with significant increases or decreases in the systemic levels of inflammatory (CRP, IL-8, and TNF-α), but it was associated with the high expression of angiotensin in vivo. These findings suggest that the job of train driving may not be associated with significant alterations in systemic immune condition, but arouse the level of angiotensin.展开更多
Summary: The effects of cyclosporine A (CsA) on Angiontensin Ⅱ (Ang Ⅱ )-induced protein contents, c los protein levels and cytosolic Ca^2+ level ([Ca^2+]i) in cultured eardiomyocytes of neonatal rats were o...Summary: The effects of cyclosporine A (CsA) on Angiontensin Ⅱ (Ang Ⅱ )-induced protein contents, c los protein levels and cytosolic Ca^2+ level ([Ca^2+]i) in cultured eardiomyocytes of neonatal rats were observed. Total protein contents were determined by Bradford method. The expression of c-fos protein was detected by Western blot. ([Ca^2+]i) labeled with fluorescent probe Fluo-3/AM was measured under a laser scanning confoeal microscope. The results revealed that as compared with control, the total protein contents were increased in cardiomyocytes treated with Ang Ⅱ (10-1 mol/ L), which could be inhibited by CsA in a dose-dependent manner. It was found that Ang Ⅱ could increase the c-los protein expression, which could be inhibited by CsA in a dose-dependent manner. Ang Ⅱ induced the [Ca^2+]i elevation in cardiomyocytes. CsA did not influence the resting intracellular Ca^2+ , but inhibited significantly the Ang Ⅱ-induced [Ca^2+]i elevation. It was concluded that CsA can suppress the Ang Ⅱ-induced c-fos protein expression and [Ca^2+]i elevation in single cardiomyocyte, which might play a role in the prevention of Ang Ⅱ-induced cardiomyocyte hypertrophy by CsA.展开更多
基金a grant from National Natural Sciences Foundation of China (No. 30500657)
文摘The changes of proto-oncogene c-fos and c-jun mRNA expression in angiotensin Ⅱ (AngⅡ)-induced hypertrophy and effects of sodium tanshinone ⅡA sulfonate (STS) in the primary culture of neonatal rat cardiomyocytes were investigated. Twelve neonatal clean grade Wistar rats were selected. The cardiomyocytes were isolated, cultured and divided according to different treatments in the medium. The cardiomyocyte size was determined by phase contrast microscope, and the rate of protein synthesis was measured by [3H]-Leucine incorporation. The c-fos and c-jun mRNA expression in cardiomyocytes was detected by reverse transcription polymerase chain reaction (RT-PCR). It was found after cardiomyocytes were treated with AngⅡ for 30 min, the c-fos and c-jun mRNA expression in cardiomyocytes was increased significantly (P〈0.01). After treatment with AngⅡ for 24 h, the rate of protein synthesis in AngⅡ group was significantly increased as compared with control group (P〈0.01). After treatment with AngⅡ for 7 days, the size of cardiomyocytes in AngⅡ group was increased obviously as compared with control group (P〈0.05). After pretreatment with STS or Valsartan before AngⅡ treatment, both of them could inhibit the above effects of AngⅡ (P〈0.05 or P〈0.01). It was suggested that STS could ameliorate AngⅡ-induced cardiomyocyte hy- pertrophy by inhibiting c-fos and c-jun mRNA expression and reducing protein synthesis rate of cardiomyocytes.
文摘Previous work from this laboratory has demonstrated that the addition of angiotensin(Aug)Ⅱresults in the rapid transcriptional activation of early growth response gene c-fos.Blockage of this increase completely inhibits the Aug Ⅱinduced increase in vascular smooth muscle cell(VSMC)growth.To explore the molecular mechanism responsible for the induction of c-fos in VSMC,a series of constructs containing portions of c-fos promoter linked to the reporter gene chloramphenicol acetyltransferase(CAT)were used in transient transfection assays.When a construct containing both the well described serum response element(SRE)and the cyclic AMP response element(CRE)was used,no endogenous CAT activity was observed in serum starved cells.The addition of either Ang Ⅱor serum resulted in a marked increase in CAT activity.Mutations in either the SRE or CRE alone which have been demonstrated to inactivate these elements in number of cell types had no effect on c-fos inducibility by either Angll or serum. In contrast,if both elements were mutated in the same construct,inducibility was reduced by 75 % ̄80%.Using a construct in which the SRE has been deleted,a mutation in the CRE completely abolished induction of c-fos by either Aug Ⅱor serum. Mobility shift assays demonstrated that tow proteins bind specifically to the SRE and three proteins to CRE. These data demonstrate that the induction of c-fos in VSMC's can be mediated by two distinct enhancer elements each of which can act independently. Future research will be aimed at identifying the proteins that interact with these elemetns delineating the mechanisms by which Ang Ⅱstimulates their activity.
文摘Train drivers are engaged in high-stress job. It may induce sleep, fatigue, and alertness loss at work, and endanger public safety. It’s unclear that cytokines of train driver would be influenced by their job. The research considers the hypothesis that stressful professions, such as train driver, influence the body’s immune system through the long-time and high-pressure working, and change production of neuro-immune factors. Using enzyme linked immunosorbent assay (ELISA), several neuro-immune factors were assayed among train drivers (N = 82) and health blood donors (N = 80) enrolled in the Yunnan Collaborative Innovation Center for Public Health and Disease Control. The concentrations of angiotensin, C-reactive protein (CRP), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-α) were determined. Kruskal-Wallis test and Dunn’s multiple comparisons test were performed for overall comparison between groups and for pairwise comparison, respectively. Statistical significance level was set at P < 0.05. The profession of train driving was not associated with significant increases or decreases in the systemic levels of inflammatory (CRP, IL-8, and TNF-α), but it was associated with the high expression of angiotensin in vivo. These findings suggest that the job of train driving may not be associated with significant alterations in systemic immune condition, but arouse the level of angiotensin.
文摘Summary: The effects of cyclosporine A (CsA) on Angiontensin Ⅱ (Ang Ⅱ )-induced protein contents, c los protein levels and cytosolic Ca^2+ level ([Ca^2+]i) in cultured eardiomyocytes of neonatal rats were observed. Total protein contents were determined by Bradford method. The expression of c-fos protein was detected by Western blot. ([Ca^2+]i) labeled with fluorescent probe Fluo-3/AM was measured under a laser scanning confoeal microscope. The results revealed that as compared with control, the total protein contents were increased in cardiomyocytes treated with Ang Ⅱ (10-1 mol/ L), which could be inhibited by CsA in a dose-dependent manner. It was found that Ang Ⅱ could increase the c-los protein expression, which could be inhibited by CsA in a dose-dependent manner. Ang Ⅱ induced the [Ca^2+]i elevation in cardiomyocytes. CsA did not influence the resting intracellular Ca^2+ , but inhibited significantly the Ang Ⅱ-induced [Ca^2+]i elevation. It was concluded that CsA can suppress the Ang Ⅱ-induced c-fos protein expression and [Ca^2+]i elevation in single cardiomyocyte, which might play a role in the prevention of Ang Ⅱ-induced cardiomyocyte hypertrophy by CsA.