Circ_BMP2K enhances the regulatory effects of miR-455-3p on its target gene SUMO1 and thereby inhibits the activation of cardiac fibroblasts.

Research has shown that some circular RNAs (circRNA) are abnormally expressed in the process of myocardial fibrosis, but the mechanism behind this was unknown. In the process of inducing cardiac fibroblast (CF) activation with TGF-ß1 or Ang II, the expression of circRNA circ_BMP2K and miR-455-3p were significantly inhibited, whereas the expression of SUMO1 was promoted. The results from our dual luciferase reporter gene assays, RIP assays, and pull-down assays show that miR-455-3p directly binds circ_BMP2K, thereby mutually promoting their expression levels. SUMO1 is a target gene of miR-455-3p, and circ_BMP2K enhances the inhibitory effects of miR-455-3p on the expression of SUMO1. Further study showed that both circ_BMP2K and miR-455-3p inhibited the expression of alpha-SMA as well as type I and type III collagen, whereas SUMO1 promoted their expression, and miR-455-3p inhibitors or overexpression of SUMO1 reversed the effects of circ_BMP2K and miR-455-3p. Circ_BMP2K and miR-455-3p inhibits cell proliferation and migration and promotes the apoptosis of CFs, but SUMO1 has the opposite effects; miR-455-3p inhibitors or overexpression of SUMO1 reverses the effects of circ_BMP2K and miR-455-3p. Thus, circ_BMP2K promotes the expression of miR-455-3p, down-regulates the expression of SUMO1, and finally, inhibits the activation, growth, and migration of CFs. These results could provide important therapeutic targets and a theoretical basis for regulating the process of myocardial fibrosis.

Correlation between the High Density Lipoprotein and its Subtypes in Coronary Heart Disease.

BACKGROUND/AIMS: To detect the changes of high density lipoprotein (HDL) and its subtypes in serum of patients with coronary heart disease (CHD). METHODS: 337 hospitalized patients were selected from our hospital during August, 2014 - January, 2015, and divided into CHD group (n = 190) and control group (n = 127). Lipoprint lipoprotein analyzer was used to classify low density lipoprotein (LDL) particle size and its sub-components, as well as HDL particle size and its sub-components. The changes of the subtypes in patients with CHD were statistically analyzed. The possible mechanism was explored. RESULTS: (1) Compared with the control group, the concentration of HDL in CHD patients reduced, HDLL significantly decreased (P < 0.001), while HDLS increased (P < 0.001); (2) In the patients with HDL less than 1.04 mmol/L among CHD, all HDL subtypes reduced, but HDLL had the most significant decreased; (3) HDL and all HDL subtypes were positively correlated with apolipoprotein A-I (apoA-I), of which, HDLL had the biggest correlation with apoA-I (P < 0.001); (4) HDL subtypes had good correlation with HDL, of which, HDLM had a maximum correlation with HDL (P < 0.001). CONCLUSION: HDL maturation disorders existed in the serum of CHD patients, HDLL may be protected factor for CHD, whose decrease was closely related wit the risk increase of CHD. The cardiovascular protection function of HDLL may be related with apoA-I content.

Angiotensin-(1-7) treatment ameliorates angiotensin II-induced apoptosis of human umbilical vein endothelial cells.

Angiotensin (Ang)-(1-7), a metabolite of AngI and AngII, is a counter-regulatory mediator of AngII. In the present study, we investigated the effects of Ang-(1-7) on AngII-induced apoptosis in human umbilical vein endothelial cells (HUVEC). To this end, HUVEC were pretreated with 10(-9), 10(-8), 10(-7) or 10(-6) mol/L Ang-(1-7) at for 30 min before being stimulated with 10(-6) mol/L Ang-II for another 24 h. Acridine orange/ethidium bromide and propidium iodide staining were used to analyse the effects of Ang-(1-7) on AngII-induced apoptosis. Alone, 10(-6) mol/L Ang-(1-7) had no effect on the apoptosis of HUVEC following exposure of cells for 30 min, whereas AngII (10(-6) mol/L, 24 h) significantly enhanced the number of apoptotic cells (P < 0.01). The AngII-induced apoptosis of HUVEC was suppressed by 10(-9)-10(-6) mol/L Ang-(1-7). The anti-apoptotic effects of Ang-(1-7) were almost completely abolished by A-779 (10(-6) mol/L, 30 min), a specific Mas receptor antagonist. In addition, Ang-(1-7) inhibited AngII-induced accumulation of cleaved caspase 3 and enhanced the expression of the anti-apoptotic factor Bcl-2 at both the mRNA and protein levels. Angiotensin II upregulated the expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), which is involved in endothelial apoptosis, at both the mRNA and protein levels. This effect was blocked by Ang-(1-7) in a concentration-dependent manner, although A-779 almost completely reversed Ang-(1-7)-mediated inhibition of AngII-induced upregulation of LOX-1. Silencing of LOX-1 using short interference RNA enhanced the protective effects of Ang-(1-7) against AngII-induced apoptosis in HUVEC. Together, the results suggest that Ang-(1-7) ameliorates AngII-induced apoptosis of HUVEC at least in part by suppressing LOX-1 expression.

[Adiponectin up-regulates the expression of T-cadherin in cardiomyocytes injured by hypoxia/reoxygenation].

The aim of the present study was to investigate the effects of adiponectin (APN) on the expression of T-cadherin in cultured Sprague-Dawley (SD) rat cardiomyocytes injured by hypoxia/reoxygenation (H/R). Primary myocardial cells from neonatal rats were obtained by enzymatic digestion. The cells were divided into control group, H/R group and H/R+APN (3, 10, 20 and 30 µg/mL) groups. The H/R group was incubated in anoxic environment (anoxic solution saturated with high concentration N2) for 3 h, and then in the reoxygenation environment (the reoxygenation solution saturated with pure oxygen) for 1 h. The H/R+APN group was pretreated with different concentrations of APN for 24 h prior to the initiation of H/R. The content of lactate dehydrogenase (LDH) was measured by chemistry chromatometry. Cellular apoptosis was analyzed by flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The expression of T-cadherin was detected by RT-PCR and Western blotting. The results showed that, compared with control group, the apoptotic rate and release of LDH were significantly increased in the H/R group, whereas the expressions of T-cad mRNA and protein were decreased. Pretreating with APN significantly and dose-dependently decreased apoptotic rate and LDH release, and up-regulated T-cad mRNA and protein level in rat neonatal cardiomyocytes under H/R conditions. These results suggest that APN may protect cardiomyocytes against H/R-induced injury by up-regulating H/R-decreased T-cad expression.

[Effects of PUMA knockout on the apoptosis of H9C2 cardiomyocytes induced by high glucose].

OBJECTIVE: To investigate the effects of p53 upregulated modulator of apoptosis (PUMA) on the apoptosis of H9C2 cardiomyocytes induced by high glucose and its mechanisms. METHODS: H9C2 cardiomyocytes were treated with 5.5mmol/L (control group) or 35 mmol/L glucose (HG group) for 6 h, 12 h, 24 h or 48 h respectively to induce apoptosis, each group sets 5 multiple wells. Apoptosis was tested by TUNEL assay. PUMA mRNA was measured by RT-PCR and protein expression was measured by Western blot assay. The mitochondrial membrane potential was detected by JC-1 method. The expressions of cleaved caspase-3 and cytochrome C (Cyt C) protein in mitochondria and cytoplasm were determined by Western blot assay. H9C2 cardiomyocytes were randomly divided into four groups, control group (5.5 mmol/L), HG (35 mmol/L) group, HG+si-scramble group(si-scramble treatment for 24 h, then 35 mmol/L high glucose treatment for 24 h) and HG-si-PUMA group (si-PUMA treatment for 24 h, then 35mmol/L high glucose treatment for 24 h). Si-PUMA was transfected into cardiomyocytes and the effects of PUMA on high glucose-induced apoptosis were studied. RESULTS: Compared with the control group, high glucose increased cardiomyocyte apoptosis and enhanced PUMA mRNA and protein expressions significantly (P＜0.05 or P＜0.01). Cell injury and increased PUMA expression were time-dependent and there was no significant difference between the high glucose 24 h group and the high glucose 48h group. The following experiment used high glucose 24 h as the stimulation time. The cardiomyocytes transfected with si-PUMA to inhibit PUMA expression had decreased apoptotic rate and cleaved caspase-3, increased mitochondria membrane potential and decreased Cyt C release (P＜0.05 or P＜0.01). There were no significant differences between the HG+si-scramble group and the high glucose group (P＞0.05). CONCLUSION: PUMA mediates high glucose-induced cardiomyocyte apoptosis suggesting PUMA may be an important target gene of diabetic cardiomyopathy.

[Glucagon like peptide-1 inhibits high glucose-induced injury of oxidative stress in cardiomyocytes of neonatal rats].

The present study was to investigate the effect of glucagon like peptide-1 (GLP-1) on high glucose-induced oxidative stress of cardiomyocytes and the possible role of the PI3K-Akt signal path in this process in the neonatal SD rats. With enzymatic digestion and immunofluorescence identification, cardiomyocytes after 72-96 h of primary culture were used in experiment. The cells were divided into 5 groups: normal control group, high glucose group, high glucose + GLP-1 group, high glucose + GLP-1 + LY294002 group and high osmolarity control group. The content of MDA was detected by TBA colouration method. The content of SOD was detected by xanthine oxidase method. The change of NADPH P47phox subunit mRNA quantity was detected by PCR gel electrophoresis. The level of ROS was detected by flow cytometry, and was also observed by fluorescence microscope. The DNA ladder was examined by agarose gel electrophoresis, and the cell apoptosis was determined by Annexin-V-FITC/PI flow cytometry, and the phosphorylation of Akt was determined by Western blotting. Compared with those in the normal control group, in the high glucose group, the cells grew poorly, and the beating rate was significantly lower (P < 0.05); The apoptotic rate was significantly increased (P < 0.05); The MDA content was increased (P < 0.05); It showed the typical DNA ladder, which is the characteristic of apoptosis; The SOD activity was decreased (P < 0.05); The level of intracellular ROS increased (P < 0.05); And the expression of NADPH P47phox subunit mRNA was increased; However the phosphorylation level of Akt was decreased. Pretreatment with GLP-1 improved the above-mentioned parameters and decreased the expression of NADPH P47phox subunit mRNA (P < 0.05). However, compared with the high glucose + GLP-1 group, LY294002, an inhibitor of PI3K-Akt signal path, attenuated the protective effect of GLP-1 in the high glucose + GLP-1 + LY294002 group. It is suggested that GLP-1 plays a protective role in the high glucose-induced injury and apoptosis of cardiomyocytes, and the PI3K-Akt signal path is involved in this process.

Scavenger Receptor BI Induced by HDL From Coronary Heart Disease May Be Related to Atherosclerosis.

This study aims to determine whether dysfunctional High Density Lipoprotein (HDL) influenced the expression of scavenger receptor class B type Ⅰ (SR-B1) to determine reverse cholesterol transport. Blood samples obtained from coronary heart disease patients confirmed by angiography were collected. HDL was extracted from the blood via ultracentrifugation. Then, the HDL was injected into apoE-/- mice, and the HepG2 cells cultured with Dulbecco's modified eagle medium (DMEM) were added the HDL extracted from coronary heart disease patients. As controls, normal cases without coronary heart disease (CHD) and patients with angina pectoris and acute myocardial infarction were used. The protein expression levels of SR-B1 were detected by western blot, and the lipid accumulation levels were detected by Oil Red O staining in both tissues and cell levels. These results revealed that the HDL obtained from CHD patients downregulate the SR-B1 expression in ex vitro and in vitro studies. In addition, dysfunctional HDL may result in lower SR-B1 expression levels. The degree of SR-B1 expression levels could be relative to the degree of coronary congestion. Along with the increase in severe coronary congestion, such as myocardial infarction, the SR-B1 expression levels were lower. The dysfunctional HDL derived from coronary heart disease patients decreased the expression of SR-B1, and promoted lipid accumulation.

[Protective effects of adiponectin against hypoxia/reoxygenation injury in neonatal rat cardiomyocytes].

The aim of the present study is to investigate the effects of adiponectin (APN) on hypoxia/reoxygenation (H/R) injury in cultured cardiomyocytes. Primary cardiomyocytes were obtained from neonatal rats by enzymatic digestion method and identified by immunofluorescent technique. Primary cells cultured for 72 h were used in experiment and divided into 5 groups randomly: Control group, H/R group, H/R+APN group, H/R+APN+adenine 9-beta-D-arabinfuranoside (AraA, AMPK inhibitor) group, and H/R+AraA group. The cardiocyte morphology and beating rate were observed under inverted microscope. The DNA ladder was examined by agarose gel electrophoresis, and the cell apoptosis was determined by flow cytometry. Moreover, the malondialchehyche (MDA) content in myocardial cells and the superoxide dismutase (SOD) activity in the supernatant were measured using kits, the fluorescence intensity of intracellular Ca2+ was observed by laser scanning confocal microscope, and the phosphorylation of AMPK was determined by Western blotting. Compared with control group, H/R group showed increased apoptotic rate, oxidative stress level, intracellular Ca2+ concentration and phosphorylation level of AMPK (P<0.05), while significant ameliorations in the above indices were seen in H/R+APN group. On the contrast, AraA attenuated the protective effect of APN and decreased the phosphorylation of AMPK. These results suggest that adiponectin can protect cardiomyocytes from H/R-induced oxidative stress and apoptosis through AMPK pathway.

[Effects of RNA interference targeting angiotensin 1 receptor and angiotensin-converting enzyme on blood pressure and myocardial remodeling in spontaneous hypertensive rats].

OBJECTIVE: To investigate the effects of RNA interference (RNAi) targeting angiotensin II Type 1 receptor (ATlR) and angiotensin-converting enzyme (ACE) on blood pressure and myocardial remodeling in spontaneous hypertensive rats (SHRs). METHODS: Saline (control), adenovirus (Ad5) and recombinant adenoviral vectors (Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA expressing ACE, AT1R, ACE and AT1R gene-specific shRNA, respectively) were randomly administered by caudal intravasation to SHRs (n = 12 each group) at day 1 and 17. Normotensive Wistar-Kyoto rats (WKY) served as normal controls. Systolic blood pressure (SBP) of the caudal artery was measured daily. Expression of ACE and AT1R at mRNA levels in ventricle and aorta were evaluated by fluorescence quantitative PCR. Angiotension II serum concentration was measured by ELISA at day 3 (n = 6 each group). The ratio of left ventricular to body weight (LVW/BW) and myocardial collagen content were measured, myocardial ultrastructure observed under transmission electron microscope at the study end. RESULTS: The caudal artery pressure of saline and Ad5 group was equally increased by about 26 mm Hg(1 mm Hg = 0.133 kPa) compared to baseline (both P < 0.05). Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA injection significantly reduced SBP (-24 mm Hg, -22 mm Hg and -26 mm Hg respectively, all P < 0.05 vs. baseline) and the antihypertensive effect could last at least 15 days post each injection. SBP was not affected by saline and Ad5 injections. ACE and AT1 mRNA expressions at ventricle and aorta were significantly decreased in Ad5-ACE-shRNA, Ad5-ACE-AT1R-shRNA and Ad5-AT1R-shRNA, Ad5-ACE-AT1R-shRNA treated SHRs compared to those in saline and Ad5 groups (all P < 0.05) and was comparable to that in WKY group (P > 0.05). The LVW/BW ratio [(2.22 +/- 0.18) microg/mg, (2.23 +/- 0.19) microg/mg, (2.17 +/- 0.16) microg/mg] and myocardial collagen content [(1.291 +/- 0.019) microg/mg, (1.298 +/- 0.019) microg/mg, (1.276 +/- 0.019) microg/mg] in Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA treated SHRs were also significantly lower than those in saline treated [(3.23 +/- 0.13) microg/mg and(1.683 +/- 0.013) microg/mg, both P < 0.05] and Ad5 treated SHRs [(3.25 +/- 0.12) microg/mg and(1.693 +/- 0.013) microg/mg, both P < 0.05], but still higher than those of WKY group [(2.06 +/- 0.12) microg/mg and (1.258 +/- 0.019) microg/mg, both P < 0.05]. Myocardial ultrastructure was also significantly improved in all SHRs underwent RNAi treatments compared to saline and Ad5 treated SHRs. CONCLUSION: RNAi targeting ACE and AT1R gene significantly inhibited myocardial and aortic ACE and AT1R mRNA expressions and resulted in prolonged antihypertensive effects and myocardial ultrastructure improvements in SHRsl. The RNAi technology may be a potential new strategy of gene therapy for hypertension.

[Effects of RNA interference targeting angiotensin-converting enzyme on the blood pressure and myocardial remodeling in spontaneously hypertensive rats].

OBJECTIVE: To investigate the effects of RNA interference (RNAi) targeting angiotensin-converting enzyme (ACE) on the blood pressure and myocardial remodeling in spontaneously hypertensive rats (SHRs). METHODS: Saline (control), adenovirus (Ad5) and recombinant adenoviral vectors (Ad5-ACE-shRNA expressing ACE gene-specific shRN) were randomly administered by caudal intravasation to SHRs (n = 12 each group) at day 1 and day 16. Normotensive Wistar-Kyoto rats (WKY) served as normal controls. Systolic blood pressure (SBP) of the caudal artery was measured daily. Expressions of ACE at mRNA and protein levels in myocardium and aorta were evaluated by RT-PCR and Western blot respectively, ACE serum concentration was measured by ELISA at day 3 (n = 6 each group). The ratio of left ventricular to body weight (LVW/BW), myocardial collagen content were measured and myocardial ultrastructure observed under transmission electron microscope at the study end. RESULTS: Ad5-ACE-shRNA injection significantly reduced SBP (-22 mm Hg, 1 mm Hg = 0.133 kPa) and the antihypertensive effect could last at least 14 days post each injection. SBP was not affected by saline and Ad5 injections. ACE expressions at mRNA and protein levels at myocardium and aorta as well as serum ACE were significantly decreased in Ad5-ACE-shRNA treated SHRs compared to that in saline and Ad5 groups (all P < 0.05) and was comparable to that in WKY group (P > 0.05). The LVW/BW ratio (2.24 +/- 0.19) and myocardial collagen content [(1.283 +/- 0.019) microg/mg] in Ad5-ACE-shRNA treated SHRs were also significantly lower than those in saline treated [3.21 +/- 0.13 and (1.686 +/- 0.013) microg/mg, both P < 0.05] and Ad5 treated SHRs [3.13 +/- 0.12, (1.682 +/- 0.009) microg/mg, both P < 0.05] but still higher than those of WKY group [2.06 +/- 0.11, (1.257 +/- 0.019) microg/mg, both P < 0.05]. Myocardial ultrastructure was also significantly improved in Ad5-ACE-shRNA treated SHRs compared to saline and Ad5 treated SHRs. CONCLUSION: RNAi targeting ACE gene significantly inhibited the expressions of ACE at mRNA and protein levels and resulted in prolonged antihypertensive effects and myocardial ultrastructure improvements in this SHR model.

[The effects of shRNA targeting angiotensin II type 1 receptor on blood pressure and AT1R mRNA expression in spontaneously hypertensive rats].

OBJECTIVE: To investigate the effects of retroviral vector containing shRNA targeting rat angiotensin II type 1 receptor (AT1R) gene (Ad5-AT1R-shRNA) on blood pressure and AT1R mRNA expression in spontaneously hypertensive rats (SHR). METHODS: Retroviral vector containing shRNA targeting rat AT1R gene was constructed and propagated further in 293 cells. SHR rats were randomly divided into SHR + Ad5-AT1R-shRNA (1.7 x 10(9) TCID(50)/ml) group and SHR (Ad5-EGFP, 7.9 x 10(9) TCID(50)/ml, n = 11 each) and 11 male Wistar-Kyoto rats (WKY) serve as normal controls (Ad5-EGFP, 7.9 x 10(9) TCID(50)/ml). Systolic blood pressure was measured before and after single intravenous injection of Ad5-AT1R-shRNA or Ad5-EGFP. Heart, liver, kidney, aorta and adrenal gland were removed after blood pressure measurement. Tissue Ad5-AT1R-shRNA expression was detected with fluorescence microscope and AT1R mRNA in liver, kidney and aorta was measured by fluorescence quantitative PCR. RESULTS: Ad5-AT1R-shRNA significantly reduced blood pressure compared with controls (-29 mm Hg, 1 mm Hg = 0.133 kPa, P < 0.05) 24 hours after single injection and this antihypertensive effect could last for 5 to 7 days. Ad5-AT1R-shRNA expression detected with fluorescence microscope was significantly increased in heart, liver, kidney, aorta and adrenal gland post Ad5-AT1R-shRNA injection. AT1R mRNA in kidney and aorta (0.086 +/- 0.014, 0.051 +/- 0.023) were significantly decreased in Ad5-AT1R-shRNA treated rats compared with SHR control rats (0.362 +/- 0.042, 0.463 +/- 0.045, P < 0.01). CONCLUSION: The results indicate that Ad5-AT1R-shRNA could inhibit the tissue AT1R mRNA expression and produce prolonged antihypertensive effects in SHR rats.

[Effects of granulocyte colony-stimulating factor on peripheral endothelial progenitor cells in cholesterol-fed rabbits].

OBJECTIVE: To investigate the effects of granulocyte colony-stimulating factor (G-CSF) on peripheral endothelial progenitor cells (EPC) and atherosclerosis (AS) in cholesterol-fed rabbits. METHODS: Male New Zealand white rabbits were randomly divided into control group, G group (Recombinant Human Granulocyte Colony Stimulating Factor Injection rhG-CSF 50 microg/d), AS group (high cholesterol diet) and G + AS group (rhG-CSF 50 microg/d plus high cholesterol diet, n = 8 per group). Peripheral blood was collected at baseline and at 1, 4, 8 and 12 weeks, total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After being cultured for 7 days, EPCs were characterized as adherent cells double positive for DiLDL uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. After being cultured for 3 days, the number of EPC (PE-CD34/FITC-CD133 double-stained positive cells) was quantified by flow cytometric analysis. Serum NO was measured and aortic plaque area analyzed at 12 weeks. RESULTS: EPC number was low in control and AS groups and EPC number was significantly increased ( approximately 13-fold, P < 0.001) compared to baseline at 1 week in G and G + AS groups and remained at this level throughout the study period in G group while decreased gradually in G + AS group and returned to baseline level at 12 weeks. Aortic atherosclerotic plaque was visible in both AS and G + AS groups, however, the aortic atherosclerotic plaque area was smaller in G + AS group than that of in As group (59.8 mm(2) +/- 26.9 mm(2) vs. 251.5 mm(2) +/- 83.4 mm(2), P < 0.01). Serum NO was similar between AS and G + AS groups and significantly higher than that in control and G groups. CONCLUSION: CSF could attenuate atherosclerosis in cholesterol-fed rabbits by increasing circulating EPC.

[Time course of G-CSF, estrogen and various doses of atorvastatin on endothelial progenitor cells mobilization].

OBJECTIVE: To evaluate the time course of granulocyte-colony-stimulating-factor (G-CSF), estrogen and various doses of atorvastatin on endothelial progenitor cells (EPCs) mobilization. METHOD: A total of 48 male New Zealand White rabbits were treated with placebo, estrogen (0.25 mg.k(-1).d(-1)), Atorvastatin (2.5, 5, or 10 mg) and G-CSF (50 microg/rabbit/d), respectively. Peripheral EPCs number was surveyed weekly for 4 weeks by FACS analysis (double-positive for PE-CD34/FITC-CD133) and under fluorescent microscope (double-positive for FITC-UEA-1/Dil-acLDL). Serum nitric oxide (NO) and lipids were also measured at the third week. RESULTS: Peripheral EPCs was significantly increased in G-CSF treated animals and remained constant for 4 weeks compared to placebo treated animals. Atorvastatin increased peripheral EPCs dose-dependently from 2.5 to 5 mg and peaked at the third week while peripheral EPCs number was not affected by 10 mg.k(-1).d(-1) atorvastatin during the first 3 weeks and was significantly higher only in the fourth week compared to placebo group. Estrogen also significantly increased peripheral EPCs at the third and fourth week compared to placebo group. At the third week, serum NO was similar in G-CSF group, significantly higher in atorvastatin 5 mg.k(-1).d(-1) and estrogen groups while significantly lower in atorvastatin 10 mg.k(-1).d(-1) group compared to placebo group. Serum lipids were similar among various groups. CONCLUSION: Atorvastatin, estrogen and G-CSF could mobilize EPCs. The mobilization efficacy is as follows: G-CSF > atorvastatin 5 mg.k(-1).d(-1) > estrogen > atorvastatin 2.5 mg.k(-1).d(-1) > atorvastatin 10 mg.k(-1).d(-1). NO might partly contribute to the mobilizing effect of estrogen and atorvastatin.

[A clinical study of hyperhomocysteinemia in rheumatological diseases].

OBJECTIVE: To analysis plasma homocysteine (Hcy) level and some relative factors in some rheumatological diseases. METHODS: 54 cases with systemic lupus erythematosus (SLE), 48 cases with rheumatoid arthritis (RA), 60 cases with ankylosing spondylitis (AS), 30 cases with undifferentiated spondyloarthropathy (uSpA) and 62 controls were recruited to participate the study. Plasma Hcy, vitamin B(12), folate and the MTHFR gene C677T polymorphism were measured in all patients and controls. RESULTS: (1) Plasma Hcy levels were higher significantly in all disease groups than in the controls, the mean plasma Hcy level was (19.04 +/- 6.86) micromol/L for SLE, (19.07 +/- 7.43) micromol/L for RA, (16.47 +/- 6.50) micromol/L for AS, (16.59 +/- 6.72) micromol/L for uSpA and (12.24 +/- 3.58) micromol/L for controls (P < 0.01). (2) Significant inverse correlation was found between plasma Hcy level and vitamin B(12), folate (r = -0.701, -0.443, respectively; P < 0.01). (3) The MTHFR gene mutation make Hcy level dramatically rise, CC genotype (13.41 +/- 5.78) micromol/L, CT genotype (16.81 +/- 4.22) micromol/L, TT genotype (20.88 +/- 6.60) micromol/L (P < 0.05). TT genotype is susceptible for hyperhomocysteinemia and SLE (OR = 84.46, 7.56 respectively; P < 0.05). CONCLUSIONS: (1) Hyperhomocysteinemia is found in most SLE, RA, AS and uSpA patients. (2) There are lots of factors associated with Hcy concentration, such as folate, vitamin B12 and MTHFR gene mutation. (3) TT genotype of MTHFR is susceptible for hyperhomocysteinemia and SLE.

LOX­1 is implicated in oxidized low­density lipoprotein­induced oxidative stress of macrophages in atherosclerosis.

Induction of oxidative stress has a causal role in atherosclerosis. The aim of the present study was to examine the role of lectin­like oxidized low­density lipoprotein receptor­1 (LOX­1) in oxidized low­density lipoprotein (OxLDL)­induced oxidative stress in atherosclerosis. Small interfering RNA (siRNA) technology was employed to decrease the expression of LOX­1 in mouse RAW264.7 macrophages and the effects of LOX­1 silencing on OxLDL­induced reactive oxygen species (ROS) generation and NADPH oxidase (NOX) expression were investigated. The in vivo effects of reducing LOX­1 were also examined in a mouse model (ApoE­/­) of high­fat diet­induced atherosclerosis. Compared with the control cells, OxLDL exposure led to a significant (P<0.05) increase in the intracellular levels of malondialdehyde and ROS and a significant decrease in the activity of superoxide dismutase. Delivery of LOX­1­targeting siRNA significantly (P<0.05) reversed the alterations in oxidative stress parameters induced by OxLDL. LOX­1 silencing downregulated the expression of NOX2, Rac1, p47phox and p22phox and impaired the activation of mitogen­activated protein kinases in OxLDL­treated cells. Adenoviral delivery of LOX­1 siRNA caused a significant increase in the size of the fibrous cap and a decrease in the macrophage content in lesions, compared with the control mice. Western blot analysis demonstrated that the protein expression levels of NOX1, Rac1, p47phox and p22phox in aortic lesions were significantly lower in the LOX­1 siRNA group than in the control group. LOX­1 is implicated in OxLDL­induced oxidative stress of macrophages in atherosclerosis, which in part, involves the regulation of NADPH oxidases.

Angiotensin-(1-7) stimulates cholesterol efflux from angiotensin II-treated cholesterol-loaded THP-1 macrophages through the suppression of p38 and c-Jun N-terminal kinase signaling.

Angiotensin II (Ang II) and Ang-(1-7) are key effector peptides of the renin-angiotensin system. The present study aimed to investigate the effects of Ang-(1-7) on Ang II-stimulated cholesterol efflux and the associated molecular mechanisms. Differentiated THP-1 macrophages were treated with Ang II (1 µM) and/or Ang-(1-7) (10 and 100 nM) for 24 h and the cholesterol efflux and gene expression levels were assessed. Pharmacological inhibition of peroxisome proliferator-activated receptor (PPAR)γ and mitogen-activated protein kinases (MAPKs) were performed to identify the signaling pathways involved. The results demonstrated that Ang II significantly inhibited the cholesterol efflux from cholesterol-loaded THP-1 macrophages. Treatment with Ang-(1-7) led to a dose-dependent restoration of cholesterol efflux in the Ang II-treated cells. The co-treatment with Ang-(1-7) and Ang II significantly increased the expression levels of adenosine triphosphate (ATP)-binding cassette (ABC)A1 and ABCG1 compared with treatment with Ang II alone. This was coupled with increased expression levels of PPARγ and liver X receptor (LXR)α. The pharmacological inhibition of PPARγ significantly (P<0.05) eliminated the Ang-(1-7)-mediated induction of ABCA1 and ABCG1 mRNA expression. Treatment with Ang-(1-7) caused the inactivation of c-Jun N-terminal kinases (JNK) and p38 MAPK signaling in the Ang II-treated THP-1 macrophages. In addition, the inhibition of JNK or p38 MAPK signaling using specific pharmacological inhibitors mimicked the Ang-(1-7)-induced expression of PPARγ and LXRα. In conclusion, the data demonstrated that treatment with Ang-(1-7) promoted cholesterol efflux in Ang II-treated THP-1 macrophages, partly through inactivation of p38 and JNK signaling and by inducing the expression of PPARγ and LXRα. Ang (1-7) may, therefore, have therapeutic benefits for the treatment of atherosclerosis.

Endogenous aldosterone is involved in vascular calcification in rat.

Aldosterone (Aldo) is an important active hormone in the renin-angiotensin-aldosterone system and plays a vital role in the development of hypertension, heart failure and other cardiovascular diseases. We aimed to explore the role of endogenous Aldo in aortic calcification in rats. We induced arterial calcification in rats by intramuscular administration of vitamin D(3) plus oral nicotine (VDN) and determined calcium content, (45)Ca(2+) accumulation and activity of alkaline phosphatase (ALP). The mRNA level of osteopontin (OPN) was measured by semi-quantitative reverse transcriptase polymerase chain reaction. Deposition of collagen in the aorta wall was measured by Sirius red staining. The content of angiotensin II (Ang II) and Aldo in plasma and myocardial and vascular tissue was determined by radioimmunoassay. In rats with VDN treatment, von Kossa staining showed calcification in vascular smooth muscle cells and extracellular matrix, and the content of calcium in calcified arteries was 5.8-fold of that in control arteries (P < 0.01). The accumulation of (45)Ca(2+) and activity of ALP in calcified aortic tissue was three- and 2.5-fold, respectively, that in control tissue (P < 0.01). The mRNA expression of OPN was significantly higher, by 58%, in calcified than control tissue (P < 0.01). Vascular fibrosis was greater in rats with calcified tissue than in control rats. The level of Ang II and Aldo was 58% and 80% higher, respectively, in calcified than control tissue (both P < 0.01). The changes could be significantly improved by treatment with captopril, an angiotensin-converting enzyme inhibitor, and the Aldo receptor antagonist spironolactone. These results suggest that Aldo is an endogenous bioactive factor involved in vascular calcification.

Angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism and ACE inhibitor-related cough: a meta-analysis.

OBJECTIVE: An insertion/deletion (I/D) variant in the angiotensin-converting enzyme (ACE) gene was associated with ACE inhibitor (ACEI)-related cough in previous studies. However, the results were inconsistent. Our objective was to assess the relationship between the ACE I/D polymorphism and ACEI-related cough by meta-analysis and to summarize all studies that are related to ACE I/D polymorphism and ACEI-cough and make a summary conclusion to provide reference for the researchers who attempt to conduct such a study. METHODS: Databases including PubMed, EMbase, Cochrane Library, and China National Knowledge Infrastructure, were searched for genetic association studies. Data were extracted by two independent authors and pooled odds ratio (OR) with 95% confidence interval (CI) was calculated. Metaregression and subgroup analyses were performed to identify the source of heterogeneity. RESULTS: Eleven trials, including 906 cases (ACEI-related cough) and 1,175 controls, were reviewed in the present meta-analysis. The random effects pooled OR was 1.16 (95%CI: 0.78-1.74, p=0.46) in the dominant model and 1.61 (95%CI: 1.18-2.20, p=0.003) in the recessive model. Heterogeneity was found among and within studies. Metaregression indicated that the effect size was positively associated with age and negatively associated with follow-up duration of ACEI treatment. Subgroup analysis revealed a significant association between ACE I/D polymorphism and ACEI-related cough in studies with mean age >60 y, but not in studies with mean age ≤ 60 y. No heterogeneity was found within each mean age subgroup. We also found no association between ACE I/D polymorphism and ACEI-related cough in studies with follow-up>2 mo or in studies in Caucasians. No heterogeneity was detected in these two subgroups. CONCLUSIONS: Synthesis of the available evidence supports ACE I/D polymorphism as an age-dependent predictor for risk of ACEI-related cough.

Adiponectin attenuates hypoxia/reoxygenation-induced cardiomyocyte injury through inhibition of endoplasmic reticulum stress.

Adiponectin (APN) is a potent cardioprotective molecule. The present study aims to investigate the underlying mechanism(s) for its cardioprotective effect. We isolated primary cardiomyocytes from neonatal rats and established an in vitro model of hypoxia/reoxygenation (H/R). The cardiomyocytes were randomly divided into 6 groups: saline group (control), dithiothreitol group (5 mM dithiothreitol for 2 hours), H/R group, H/R + APN group (incubation with 30 µg/mL APN, followed by H/R), H/R + APN + SB203580 (SB) group (treatment with 30 µg/mL APN and 5 µM SB, followed by H/R), and H/R + SB group (exposure to 5 µM SB and then H/R). Cell death was detected by measuring lactate dehydrogenase release. The expression levels of hypoxia-inducible factor 1α and endoplasmic reticulum stress-related genes including GRP78, caspase-12, C/EBP homologous protein, and p38 mitogen-activated protein kinase were examined. Cardiomyocytes exposed to H/R showed a significant increase in lactate dehydrogenase leakage and hypoxia-inducible factor 1α protein levels compared with the control cells (P < 0.05). The H/R-provoked cell death was profoundly attenuated by the pretreatment with APN alone, SB alone, or both, which was coupled with decreased expression of GRP78, caspase-12, C/EBP homologous protein, and p38 mitogen-activated protein kinase. These results provide new insights into the mechanism of APN-mediated cardioprotection, which may be partially due to inhibition of endoplasmic reticulum stress response.