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Objective To investigate the cardiac protection of Hsp27 against endotoxic cardiac depression mediated by activation of PI3K/Akt pathway and the suppression of NFκB-mediated inflammatory response in mice. Method (1) Transgenic mice with cardiac specific overexpression of Hsp27 (Hsp27 Tg) and wild littermate controls (WT) were given 10 mg/kg LPS injected intraperitoneally to induce endotoxemia, (2) The cardiac function measurement in mice was performed by using echocardiography 6 hours after LPS treatment (n = 6), (3) The activity of PBK/Akt pathway was evaluated by Western blot for [hosphor-Akt (p-Akt) and phosphor-Gsk-3β (p-Gsk-3β) one hour after LPS administration ( n = 4)], (4) Activity of inflammatory response was evaluated by protein degradation of IκBα (n = 4), (5) The apoptosis of myocardial cells was determined by TUNEL assay on the paraffin section of cardiac tissue 24 hours after LPS exposure (n = 4). Results (1) Hsp27 attenuated cardiac dysfunction significantly following LPS treatment. Compared with the primary value, LPS induced the depression of cardiac function both in WT rats and Hsp27Tg rats. However, the cardiac dysfunction was attenuated significantly in Hsp27Tg rats compared with that in WT rats ( P < 0.01 or 0.05) . (2) Hsp27 attenuated IκBα degradation after LPS administration. Compared with the primary value, LPS led to LκBα degradation by (72.92 + 9.20) % in WT rats and by (41.43 + 24.10) % in Hsp27Tg rats. The overexpression of Hsp27 lessened the IκBα degradation significantly (P < 0.05). The similar results were obtained in rat myocardial cell culture of experiments. (3) Hsp27 enhanced the activation of PI3K/Akt signaling following LPS exposure. One hour after LPS administration, the relative levels of p-Akt and p-GSK-30 were (3.11 + 0.83) and (3.19 + 1.04), respectively in WT rats, and (5.13 + 0.73) and (5.71 + 1.20) in Hsp27Tg rats, respectively. Compared with WT rats, the levels of p-Akt and p-GSK-3β were significantly higher in Hsp27Tg rats (P < 0.05). (4) The Hsp27 lessened LPS-induced the apopto-sis of myocardial cells. Twenty-four hours after LPS treatment, the percentages of myocardial cell apoptosis were (6.46+ 1.74)% in WT rats and (2.88 + 0.91)% in Hsp27Tg rats. Compared with WT rats, LPS-induced apoptosis in myocardial cells was significantly decreased in Hsp27Tg rats (P < 0.01). Conclusions The overexpression ofHsp27 attenuates cardiac dysfunction significantly during endotoxemia, and the mechanisms may be attributed to the activation of PDK/Akt signaling pathway.
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Objective To evaluate the relationship of central aortic pressure (CAP) with atherosclerosis and left ventricular function in elderly patients with essential hypertension. Methods A total of 155 elderly hypertensive patients were divided into two groups: aged 60-79 years group (n = 71) and aged 80-95 years group (n= 84). Central aortic waveforms were generated using pulse wave analysis, then CAP and augmentation index (AI) were determined. Auto-survey atherosclerosis apparatus was applied to examine brachial-ankle pulse wave velocity (baPWV), ankle-brachial index (ABI) and toe-brachial index (TBI). Interventricular septal thickness at end diastole (IVSd), left ventricular end-diastolic dimension (LVDd), left ventricular posterior wall thickness at end diastole (LVPWd), relative left ventricle thickness (RLVT), left ventricular mass index (LVMI), Ejection fraction(EF) slope, left ventricle ejection fraction (LVEF) and fractional shortening (FS) were measured by the two-dimensional echoeardiography. Results Systolic pressure (SBP), pulse pressure (PP), CAP, AI and baPWV were significantly higher in aged 80-95 years group than in aged 60-79 years group (all P<0.05), ABI and TBI were significantly lower oppositely (both P<0. 01). IVSd, LVPWd, RLVT and LVMI were all significantly higher and EF slope was lower in aged 80-95 years group than in aged 60-79 years group (all P<0. 057. There were no significant differences in LVDd, LVEF and FS between the two groups (both P>0. 05). CAP had positive association with PP, AI and baPWV (r=0. 505,0. 284,all P<0.01). After adjustment for age, gender, smoking, body mass index, fasting blood sugar, creatinine, uric acid, cholesterol, triglyceride, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, there was no significant relationship between CAP and ABI or TBI (both P>0. 05). There was also positive association of CAP with IVSd, LVPWd, RLVT, LVMI, while negative associations of CAP with EF slope (all P<0. 01). There were no significant relationship between CAP and LVEF, FS, LVDd (all P> 0.05). Conclusions CAP and degree of artherosclerosis increase with aging in elderly patients with essential hypertension, which contributes to left ventricular hypertrophy and the decreased diastolic function. CAP helps to make an early diagnosis of or screening arteriosclerosis, and it is an important forecast factor for cardiovascular disease.
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Objective To investigate the protective effect of the extract of ginkgo biloba on myocardial tissue in aged rat.Methods The rats aged 20 months were given the extract of ginkgo biloba (EGB) and ALT-711 respectively by garage for 16 weeks.The aged controls and adult rats were infused with the same volume saline.The superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), malonyt diadehyde (MDA) in blood samples and advanced glycation end products (AGEs) in the myocardial tissue were measured .The myocardial histopathological changes under electron microscope and the mitochondrial DNA (mtDNA) deletion rate in myocardial cells were observed.Results Compared with the adult rats, the content of AGEs in myocardial cells in aged rats was significantly increased [(33.5±1.3)AU/mgHYP us.(18.1±1.2)AU/mgHYP, t= 7.18,P<0.05] and the levels of SOD and GSH-PX in blood samples were decreased [(138.4±3.8) U/mlvs.(227.7±13.8)U/ml, (1283.8±28.8) U/ml vs.(2114.1 ±135.9)U/ml, t=-19.59, -18.79;both P<0.01].The MDA level in the serum and mtDNA deletion rate in aged rats were higher than in adult rats[(6.7±0.6) mmol/ml vs.(4.1±1.0) mmol/ml, (0.18054±0.0718) % vs.( 0.0060±0.0001)%, t=7.18,6.98;both P<0.05].Compared with the aged controls, the content of AGEs in myocardial cells, the level of MDA and mtDNA deletion rate were significantly decreased in EGB and ALT-711 treatment adults (all P<0.05).The SOD and GSH-PX in blood samples were increased in EGB and ALT-711 treatment adults (all P<0.05).Conclusions Nonenzymatic glycation may play an important role in myocardial aging, which may be amplified by oxidative stress.EGB and ALT-711 may have the same anti-aging effects by inhibiting nonenzymatic glycation and oxidative stress.
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Objective To study the effects of heat shock proetin 27(Hsp27)on the cardiac dysfunction induced by endotoxemia.Method All experiments were performed in the geriatric lab of the First Affiliated Hospital Of Nanjing Medical University,and in the Animal Model Center of Nanjing University.The genotyping of the transgenic mice with cardiac-specific overexpression of Hsp27(Hsp27 Tg)was assayed by PCR and the expression of Hsp27 was determined by western blot.Hsp27 Tg and its wild type littermates(WT)were intraperitoneally injected with LPS(10 mg/kg),and 24 hours later,cardiac function was measured by echocardiography(n=6/group).The accumulated mice mortality was recorded within 70 hous after intraperitoneal injection of LPS(20mg/kg)(n=37/WT,n=27/Hsp27Tg).The NF-kB activity for cardiac-tissue samples was analyzed by electrophoretic mobility shift assay(ENSA)and for cell culture samples by dual-reporter gene assay(n=4/group).The comparison of multiple groups was performed by one-way analysis of variance(ANOVA),and comparison of two groups was performed by Scheffe-test.Survival curves were analyzed by the log-rank test.P＜0.05 wns considered to be significant.Results The high expression of Hsp27 exhibited in myocardium of Hsp27 Tg,whereas not in myocardium of WT.LPS significantly reduced the cardiac function both in Hsp27 Tg and WT.However,compaled with LPS-treated WT,cardiac function was more significantly improved as evidenced by the increases of EF by 27.33%and FS by 37.09%(P＜0.01 or P＜0.05).Seventy hours after LPS injection,the mortality was 11.11% in Hsp27 Tg and 37.84% in WT.Compared with WT,the survival rate of Hsp27 Tg significantly increased(P＜0.05).The NF-kB activation was significantly inhibited by Hsp27(P＜0.01 or P＜0.05).Conclusions The high cardiac-specific expression of Hsp27 significantly inhibits cardiac dysfunction induced by endotoxemia,and at the same time improve the survival rate.The mechanism may be connected with Hsp27 downregulating NF-kB-activation induced by LPS.
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Objective To investigate the relationship between lower limb artherosclerosis and cardiac function in elderly patients with diabetes mellitus(DM)complicated with coronary heart disease (CHD). Methods 441 cases of elderly patients were divided into four groups: the group with CHD (n=117), the group with DM(n=42), the group with DM compllicated with CHD( DM±CHD, n=132),the group without DM and CHD(NC,n=150). Systolic blood pressure (SBP), diastolic blood pressure(DBP), pulse pressure (PP), braehial-ankle pulse wave velocity (baPWV), ankle-brachial index(ABl) and toe-brachial index(TBI) were measured by the auto-survey artherosclerosis apparatus.Left ventricular posterior wall (LVPW), left atrium (LA), fractional shortening (FS), ejection fraction(EF) and EF slope were measured by the two-dimensional echocardiography. Results The baPWV was significantly higher in DM+CHD group than in DM group and NC group[(20125±354)cm/s vs (1849±467)cm/s, (1863±347) cm/s. P<0.05]. The ABI was significantly lower in DM±CHD group compared with NC, CHD and DM groups (0.91±0.23 vs 1.15±0.11,1.07±0.16 and 1.06±0.14. all P＜0.05). There were significant differences in TBI among four groups(all P<0.05) :NC group(0.905±0.15)>CHD group(0.805±0.16)>DM group(0.71±0.17)>DM+CHD group(0.625±0.17). The LA and the LVPW were significantly higher in DM+CHD group than in NC group(P<0.05). The FS and EF slopes were significantly lower in the DM+CHD group than in DM group (P<0.05) and NC group(P<0.05). The EF in DM+CHD group was significantly lower than that in other three groups (P<0.05). BaPWV showed a strong negative association with FS,EF and EF slope(r:-0.112,-0.151,-0.275. all P<0.05). ABI showed a strong positive association with FS,EF and EF slope(r:0.150,0.186,0.260. all P<0.01) ,TBI was found to have strong negative association with LA and LVPW ( r:-0.158,-0.171;all P<0.01) and have strong positive association with FS,EF and EF slope(r:0.163,0.197,0.243.all P<0.01). Conclusions The lower limb artherosclerosis is serious and cardiac function is significantly decreased in elderly patients with diabetes mellitus complicated with coronary heart disease. PWV,ABI and TBI are closely related with cardiac function and can reflect the state of cardiac function in some extent.
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BACKGROUND: Angiotensinogen (AGT) gene is the firstly discovered candidate gene for essential hypertension, both the T174M and M235T polymorphisms locate at the second exons of AGT gene, and there is existence of linkage disequilibrium. The polymorphism at A-6G and G-217A sites in promotor region plays an important role in regulating the gene expression, and the products of keep close correlation with the level of blood pressure. OBJECTIVE: To investigate the association between the polymorphism of AGT gene at A-6G, T174M and G-217A sites and the risk for the attack of essential hypertension in Chinese Han population, DESIGN: A cluster sampling and case-control analysis. SETTINGS: Department of Geriatrics and Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University; Southern Research Center of National Human genome; Department of Cardiology, Dongtai People's Hospital of Jiangsu Province. PARTICIPANTS: The experiment was carried out in the countryside of Dongtai county, Yancheng city, Jiangsu province. All the subjects were selected from the countryside of Dongtai county, Yancheng city, Jiangsu province. Totally 177 patients with essential hypertension who had never accepted any drug treatment, were taken as the essential hypertension group, and hypertension was diagnosed according to the diagnostic standard of hypertension set by WHO/ISH in 1999 (systolic blood pressure ≥ 140 mm Hg and/or diastolic blood pressure ≥ 90 mm Hg); Another 86 normal person were taken as the normal control group. ② Inclusive criteria: The enrolled subjects should be Han nationality; long-term local residents but not from other places; able to answer questions clearly; diagnosed by disease history, clinical symptoms, physical signs and assistant examinations; have complete data of investigation of uniform questionnaires by face-to-face interview (including demographic information, profession history, family history and life styles of smoking, drinking, drinking tea, etc.). ③ Exclusive criteria: The patients with secondary hypertension in the essential hypertension group, subjects having family hisory of hypertension in the normal control group, and those with chronic diseases of liver and kidney, and diabetes mellitus in both groups were excluded. METHODS: Peripheral venous blood samples (3 mL) were collected, and DNA was extracted from human peripheral blood with FlexiGene DNA Kit (250). The Primer3 software was applied to design primers, and the polymorphism sites in the primer sequence were excluded. After multiplex polymerase chain reaction (PCR), 3 μL products were selected to detected the amplified results by agarose gel electrophoresis. The successfully amplified PCR products were purified with the QIAquick PCR Purification Kit, and the purified products were fragmentized with Dnase Ⅰ . The fragmentized products of enzyme digestion were labeled with fluorescein by deoxynucleotide terminal transferase. Two allele specific probes and one mismatched probe were designed respectively for each single nucleotide polymorphism. The chips were prepared with the OmniGridTM 100 TLC samler, each probe was repeated for three times to form three matrix. The hyridization solution was degenerated at 95 ℃ for 10 minutes, and then immediately cut on ice. 10 μL hybridization solution was added onto the chip matrix, hybridized at 50 ℃ for 2 hours, then washed and dried. The chips were scanned with the GenePix 4000B laser confocal scanner (Figure 2),and the intensity of the fluorescent signal for each probe was extracted with GenePix Pro, and the allele score of each single nucleotide polymorphism was calculated to judge the genotype. MAIN OUTCOME MEASURES: ① Comparison of the frequencies of genotype distribution at each polymorphism site of AGT gene in both groups; ② Correlation analysis of the polymorphism of AGT gene at A-6G and T-174M sites with the risk for the attack of essential hypertension; ③ Effects of the polymorphism of AGT gene at A-6G, T-174M and G-217A sites on blood pressure.RESULTS: According to the intention-to-treat analysis,all the 263 subjects were involved in the analysis of results. ① At the A-6G site of AGT gene, the frequencies of AA, AG and GG genotypes (P=0.014) and A and G alleles (P=0.004, OR=0.44) had significant differences between the essential hypertension group and normal control group; At the T174M site, the frequencies of CC, CT and TT genotypes (P=0.031) and A and G alleles (P=0.014, OR=0.55) were significantly different; At the G-217A site, no obvious differences were found in the GG, AG and AA genotypes (P=0.722) and G and A alleles (P=0.403, OR=0.80). ② The risk of essential hypertension in the individuals carrying AA genotype of A-6G polymorphism and CC genotype of T174M polymorphism was reduced by 57% (95%CI= 0.23-0.82, P= 0.010) and 56% (95%CI= 0.25-0.79, P= 0.006) respectively. ③ There were no significant differences in the systolic blood pressure, diastolic blood pressure and mean arterial pressure among different genotypes at the A-6G, T174M sites and G-217A sites (F=0.100- 2.911, P ＞ 0.05). CONCLUSION: The AA genope at A-6G and the CC genotype at T174M site of AGT gene may reduce the risk for the attack of essential hypertension in Chinese Hun population, and no significant correlation was found between the genotype of G-217A polymorphism and the attack of essential hypertension.
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BACKGROUND: A good many researches believe that the gene polymorphism of vascular endothelia nitric oxide synthase(eNOS) correlate with diseases of heart, brain and kidney. However, it is still not clear whether eNOS Glu298Asp correlates with myocardial infarction in the elderly Chinese.OBJECTIVE: To investigate the distribution of Glu298Asp polymorphism of vascular eNOS in the elderly as well as correlation between Glu298Asp polymorphism of eNOS and myocardial infarction in the elderly Chinese.DESIGN: A case-controled study based on diagnosis.SETTING, PARTICIPANTS and METHODS: A total of 37 patients with myocardial infarction were selected into case group, which all of them were patients from either outpatient department or inpatient department of the First Affiliated Hospital of Nanjing Medical University. Thereinto, 20 cases without hypertensive history were allocated into case subgroup. Totally 172 subjects selected from the re-testees of physical checkup of our hospital were assigned into control group, of which 92 cases without hypertensive history were allocated into control subgroup. Indices like height, body mass and fasting blood sugar were detected respectively in all participants of all groups. The polymorphism of Glu298Asp of eNOS gene was assayed by polymerase chain reaction(PCR), and restriction fragment length polymorphism (RELP).MAIN OUTCOME MEASURES: The polymorphism of Glu298Asp of eNOS gene as well as the allelic frequency of 298Asp in the elderly of four groups.RESULTS: Genotype of Glu/Asp of the case group was higher than that of the control group(32.43% and 18.02% respectively) . The genotype composition of Glu298Asp polymorphism had significant difference between the case group and the control group(x2 = 3.87, P < 0. 05) . Between normotensive subgroups, Genotype Glu/Asp of the case subgroup was higher than that of the control subgroup(35.00% and 10. 87% respectively) . The genotype composition of Glu298Asp polymorphism of the eNOS gene also had significant difference between the case subgroup and the control subgroup (x2 = 7.43, P < 0.01) . The allelic frequency of 298Asp of the case group was higher than that of the control group without statistical significance (16. 22% and 9.01% respectively, P > 0. 05) . Between normotensive subgroups, the allelic frequency of 298Asp of the case subgroup was significantly higher than that of the control subgroup(17.50% and 5.43% respectively, x2 = 6.82, P < 0.01 ) ).CONCLUSION: Glu298.Asp polymorphism of the eNOS gene exists in the elderly Chinese. The genotype of Glu/Asp and allelic frequency of 298Asp might be a genetic susceptible marker of myocardial infarction in the elderly Chinese.
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Objective To explore the association of Glu298Asp polymorphism of the endothelial nitric oxide synthase gene (eNOS) with myocardial infarction in Chinese aged people based on a case-control study. Methods Thirty-seven patients with myocardial infarction and 172 sex- and age-matched healthy control subjects were enrolled. Their height, weight and blood pressure were measured and the fasting plasma lipid concentrations were examined. Glu298Asp polymorphisms of the eNOS gene were examined using PCR and RFLP methods. Results Genotype Glu/Asp in the patient group was higher than that in the control group (32.4% vs 18.0%). The genotype composition of Glu298Asp polymorphism showed significant difference between the patient group and the control group ( =3.87, P 0.05). Among the normotensive subgroup, the allelic frequencies of 298Asp in the patient subgroup was higher than that in the control subgroup (17.5% vs 5.4%). The allelic frequencies of 298Asp had significant difference between the patient subgroup and the control subgroup ( =6.82, P
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Aim To explore the role of cytoplasmic FKBP52 in AAV-mediated transduction.Methods Murine embryo fibroblasts(MEFs)cultures from FKBP52 wild-type(WT),heterozygous(HE),and knockout(KO)mice were established.The role of FKBP52 in intracellular trafficking of AAV was analyzed by fluorescence-activated cell sorting(FACS)analyses,electrophoretic mobility shift assays(EMSA),southern blot,immunoprecipitations and western blot analyses.Results Conventional AAV vectors failed to transduce WT MEFs efficiently,and the transduction efficiency was not significantly increased in HE or KO MEFs.AAV vectors failed to traffick efficiently to the nucleus in these cells.Treatment with hydroxyurea(HU)increased the transduction efficiency of conventional AAV vectors by～25-fold in WT MEFs,but only by～4-fold in KO MEFs.The use of self-complementary AAV(scAAV)vectors,which bypass the requirement of viral second-strand DNA synthesis,revealed that HU treatment increased the transduction efficiency～23-fold in WT MEFs,but only～4-fold in KO MEFs,indicating that the lack of HU treatment-mediated increase in KO MEFs was not due to failure of AAV to undergo viral second-strand DNA synthesis.Following HU treatment,～59% of AAV genomes were present in the nuclear fraction from WT MEFs,but only ～28% in KO MEFs,indicating that the pathway by which HU treatment mediates nuclear transport of AAV was impaired in KO MEFs.When KO MEFs were stably transfected with an FKBP52 expression plasmid,HU treatment-mediated increased in the transduction efficiency was restored in these cells,which correlated directly with improved intracellular trafficking.Intact AAV particles were also shown to interact with FKBP52 as well as with dynein,a known cellular protein involved in AAV trafficking.Conclusion These studies suggest that FKBP52,being a cellular chaperone protein,facilitates intracellular trafficking of AAV,which has implications in the optimal use of recombinant AAV vectors in human gene therapy.
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Objective To determine the effect of mitochondria on the protection of heat-shock proteins B1(HSPB1) from oxidative damage in rat cardiac cell.Methods HSPB1 gene-transfected rat cardiomyocytes cell line H9c2 (HSPB1 H9c2) and empty vector transfected H9c2 (control) were established,and treated by 0-1000?mol/L H_2O_2 for 2h.And then the cell morphology, mitochondrial membrane potential and endogenous reactive oxygen species (ROS) were detected. Results (1)HSPB1 inhibited the morphological changes induced by H_2O_2 markedly.(2)HSPB1 inhibited the loss of mitochondrial membrane potential induced by H_2O_2.Following the stimulation of 0,75,150,300,500,1000?mol/L H_2O_2,mitochondrial membrane potential in HSPB1 and control H9c2 cells were (10.0?0.11)vs (7.01?0.26),(9.11?0.17)vs (6.05?0.19),(7.69?0.28)vs (5.14?0.28),(6.95?0.13)vs (4.66?0.11),(6.61?0.20)vs (1.85?0.35),(6.60?0.05)vs (1.19?0.01),respectively (all P0.05).Conclusions HSPB1 protects rat cardiomyocytes cell line(H9c2) from oxidative damage,which suggests that stabilization of mitochondrial membrane potential and the decreased endogenous reactive oxygen species after oxidative stress may be involved in the protection of HSPB1 against oxidative stress in H9c2.