[Associations between G1165C and A145G polymorphism of ß1-adrenoceptor and resting heart rate in the Northern Han Chinese].

OBJECTIVE: To systematically investigate the possible associations between G1165C and A145G polymorphism of ß1-adrenoceptor (ADRB1) and resting heart rate (HRrest) in Northern Han Chinese. METHODS: HRrest of 700 healthy Northern Han Chinese were measured in the sitting position.SNPs were genotyped by the TaqMan assay.Genotypes were differentiated by analyzing the fluorescence levels of PCR products using an ABI Prism 7900HT Sequence Detector. RESULTS: HRrest was significantly lower in A145G AA carriers than in AG and GG carriers (all P < 0.01) . Multiple linear regression analysis showed that age, smoking habits, systolic blood pressure, triglyceride, serum creatinine and A145G polymorphism were associated with HRrest (P < 0.01) . A145G was significantly related with HRrest independent of other possible confounding variables, and the partial regression coefficient was 2.148 (P < 0.05) . After adjusting for other confounding factors, significant association between A145G and HRrest was only found in male subjects (P < 0.05) but not in female subjects (P > 0.05) . CONCLUSION: The A145G polymorphism of ADRB1 gene is associated with HRrest in Northern male Han Chinese.

[Association of C602A and T1559C polymorphisms of E-selectin gene and essential hypertension].

OBJECTIVE: To investigate the possible genetic associations between the C602A and T1559C polymorphisms of E-selectin (SELE) and essential hypertension. METHODS: Essential hypertensive patients (n = 500) and healthy normotensive subjects (n = 930) were screened for the genotypes C602A and T1559C by real-time quantitative polymerase chain reaction after DNA extraction to identify representative variations in the SELE gene. RESULTS: Normotensive subjects and hypertensive patients were significantly different with respect to the genotypes CC, CA and AA, 26 (5.2%), 20 (4.0%) and 454 (90.8%) vs 14 (1.5%), 53 (5.7%) and 863 (92.8%) respectively of C602A. And the C-allele frequency was also significantly different between the NT and EH groups (C, A = 7.2%, 92.8% vs 4.4%, 95.6%). When subgrouped by gender, frequency of CC, CA, AA between normotensive and essential hypertensive males was 14 (4.7%), 11 (3.7%), 272 (91.6%) and 10 (1.7%), 34 (5.8%), 545 (92.5%), which differed significantly (P < 0.05), while in female groups, all the frequency of genotypes were significantly different (P < 0.01) except CC + CA. The additive model (TT, TC, CC) of the T1559C genotype was significantly different between essential hypertensive and normotensive groups overall, 57 (11.4%), 200 (40.0%), 43 (48.6%) and 66 (7.1%), 354 (38.1%), 510 (54.8%), respectively. The T-allele of hypertensive patients significantly differed from normotensive subjects (T, C = 31.4%, 68.6% vs 26.1%, 73.9% respectively). When subgrouped by gender, between the male NT and EH groups, the TT, TC and CC frequency of T1559C were 36 (5.9%), 117 (39.4%), 144 (48.5%) and 35 (5.9%), 230 (39.0%), 354 (55.0%), and the frequency of T vs C was 31.4% vs 68.6% and 26.1% vs 73.9%, which were significantly different (all P < 0.01). As in female NT and EH groups, there were not significant differences existed at all. CONCLUSION: C602A and T1559C of SELE are associated with essential hypertension in the Chinese population, and T1559C is closely related with male hypertension other than in females.

[Relationship between genetic polymorphisms of ß2-adrenergic receptor gene and essential hypertension risk among the Han Chinese population: a Meta analysis].

OBJECTIVE: To evaluate the relationship between A46G and C79G polymorphisms in the ß2-adrenergic receptor (ADRB2) gene and the incidence of essential hypertension (EH) among the Han Chinese population. METHODS: We conducted a computer retrieval of PUBMED, EMBASE, CNKI, Wanfang and VIP databases prior to May 2010. Articles investigating the relationship of EH and ADRB2 gene polymorphism of Han group were found through literature search, including 15 articles on A46G and 10 articles on C79G. According to the including and excluding criteria, a Meta-analysis was conducted in EH and ADRB2 gene polymorphism of A46G and C79G. The association was examined by RevMan4.2 software through quantitative analysis. RESULTS: Eight articles on A46G polymorphism (including 1078 EH cases and 788 control subjects) and six articles on C79G polymorphism (including 1367 EH cases and 1006 control subjects) were included in the current study. Meta-analysis showed that there was a significant association between A46G polymorphism and EH: genotype GG/(AA + AG) (fixed-effected model, OR = 1.35, 95%CI = 1.04 - 1.74, P = 0.02), genotype GG/AA (fixed-effected model, OR = 1.41, 95%CI = 1.06 - 1.89, P = 0.02). No significant association was found between C79G polymorphism and EH of Han group in China: G/C allele comparison (random-effected model, OR = 0.88, 95%CI = 0.55 - 1.39, P = 0.57). CONCLUSION: Significant association was found between A46G polymorphism of ADRB2 gene and EH, whereas no association could be found between C79G polymorphism and EH among Han Chinese population.

[Plasma proteomic analysis in male normotensive, prehypertensive and hypertensive subjects].

OBJECTIVE: To compare the plasma proteome among male normotensive, prehypertensive, and hypertensive subjects. METHODS: Plasma proteome was analyzed by two-dimensional electrophoresis combined with MALDI-TOF mass spectrometry in this case-control study among well matched male normotensive, prehypertensive and hypertensive subjects (n = 26 each). RESULTS: The results showed that there were 22 differentially expressed protein spots among the protein samples derived from the 3 groups which corresponded to 18 proteins associated with inflammation and immunity, lipid metabolism, transport, coagulation and fibrinolysis, cell proliferation and apoptosis, and antioxidation. CONCLUSION: Proteins were differentially expressed in male subjects with various blood pressure levels.

[Pericardial endothelin secretion in patients underwent open heart surgery.].

OBJECTIVE: To evaluate pericardial endothelin (ET) secretion by the human pericardial mesothelial cells. METHODS: Plasma, pericardial fluid and pericardial tissue were obtained in 51 patients receiving open heart surgery (coronary artery bypass grafting, elective heart valvuloplasty or valve replacement). ET concentrations in the plasma, pericardial fluid and pericardial tissues were measured by radioimmunoassay (RIA). ET mRNA expression in the human pericardium was detected by in situ hybridization. RESULTS: (1) The levels of ET in human pericardial fluid was significantly higher than that in the plasma [(128.8 +/- 44.0) ng/L vs. (93.7 +/- 28.6) ng/L, P < 0.001]; (2) ET concentration in the pericardial tissue was (510.3 +/- 156.7) ng/kg; (3) In situ hybridization technique evidenced the abundant ET mRNA expression in human pericardial mesothelial cells. CONCLUSION: The study indicated that pericardium secreted ET into the pericardial space.

Human vascular smooth muscle cells and endothelial cells cocultured on polyglycolic acid (70/30) scaffold in tissue engineered vascular graft.

BACKGROUND: Current prosthetic, small diameter vascular grafts showing poor long term patency rates have led to the pursuit of other biological materials. Biomaterials that successfully integrate into surrounding tissue should match not only the mechanical properties of tissues, but also topography. Polyglycolic acid (70/30) has been used as synthetic grafts to determine whether human vascular smooth muscle cells and endothelial cells attach, survive and secrete endothelin and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha). METHODS: Endothelial cells and smooth muscle cells were isolated from adult human great saphenous vein. They were seeded on polyglycolic acid scaffold in vitro separately to grow vascular patch (Groups A and B respectively) and cocultured in vitro to grow into vascular patch (Group C). Smooth muscle cells and endothelial cells were identified by immunohistochemical analysis and growth of cells on polyglycolic acid was investigated using scanning electron microscopy. The levels of endothelin and 6-keto-PGF1alpha in the culturing solutions were examined by radioimmunology to measure endothelial function. RESULTS: Seed smooth muscle cells adhered to polyglycolic acid scaffold and over 28 days grew in the interstices to form a uniform cell distribution throughout the scaffold. Then seed endothelial cells formed a complete endothelial layer on the smooth muscle cells. The levels of endothelin and 6-keto-prostaglandin F1 alpha in the culturing solution were (234 +/- 29) pg/ml and (428 +/- 98) pg/ml respectively in Group C and (196 +/- 30) pg/ml and (346 +/- 120) pg/ml in Group B; both significantly higher than in Groups A and D (blank control group, all P < 0.05). CONCLUSIONS: Cells could be grown successfully on polyglycolic acid and retain functions of secretion. Our next step is to use human saphenous vein smooth muscle cells and endothelial cells to grow tubular vascular grafts in vitro.

[Increased plasma vasoactive substances and antioxidant enzymes levels in prehypertensive patients].

OBJECTIVE: This study investigates the plasma vasoactive substances and antioxidant enzymes levels in prehypertensive patients. METHODS: Patients were scruited according to JNC-7 and divided into three groups: 74 normotensive subjects (NT group, 38 males, mean age 47.15 +/- 7.77 years old); 51 prehypertensive patients (PH group, 29 males, mean age 47.82 +/- 5.16 years old) and 71 essential hypertensive patients (EH group, 37 males, mean age 48.25 +/- 7.97 years old). Serum lipids and plasma angiotensin II (Ang II), endothelin (ET), vasopressin (AVP), calcitonin gene-related peptide (CGRP), nitric oxide synthase (NOS), superoxide dismutase (SOD) and glutathione peroxidase (GPX) by radioimmunoassay and enzyme linked immunosorbent assay. RESULTS: Serum Lipids (TG, CHO and LDL) were significantly higher in the PH and EH groups compared to NT group (all P < 0.05). Ang II, AVP and ET were significantly increased while CGRP decreased in the EH group than that in NT group (all P < 0.05). SOD was significantly lower while GPX significantly higher. Further more, in the PH and EH groups than those in the NT group (all P < 0.05). CONCLUSION: SOD was reduced and GPX increased in prehypertensive patients.

[Hyperplasia suppressor gene expression in vascular smooth muscle cells derived from normotensive and hypertensive patients underwent bypass surgery].

OBJECTIVE: To investigate the novel hyperplasia suppressor gene (HSG) expression in vascular smooth muscle cells derived from normotensive and hypertensive patients underwent bypass surgery. METHODS: Coronary heart disease patients underwent coronary artery bypass graft (CABG) operation in BEIJING ANZHEN hospital from 4 - 9, 2006 were enrolled in this study and divided into hypertensive group (n = 28) and normotensive group (n = 26). The preoperative venous blood samples were taken for serum biochemical and vasoactive peptides measurements. Total RNA was extracted from WBC, explanted-vessels and cultured VSMCs using TRIZOL and HSG expression was determined by Semi-Quantitative RT-PCR. RESULTS: Body mass index (BMI) was significantly higher in hypertensive group compared to normotensive group (P < 0.01) while other biochemic parameters and vasoactive peptides were similar between the groups. BMI and GLU, BMI and SBP, BMI and DBP, GLU and TG, SBP and DBP were positively correlated (all P < 0.05). HSG expression in WBC, VSMCs and vessel tissue were significantly lower in hypertensive group than those in normotensive group (all P < 0.05). HSG expression in tissue was negatively correlated to BMI, SBP and DBP (all P < 0.05). CONCLUSIONS: Reduced HSG expression and the negative correlation on vascular tissue HSG expression to BMI, SBP and DBP suggested a possible inhibitory role of HSG on VSMC proliferation and blood pressure.

Second-generation versus first-generation drug-eluting stents in saphenous vein graftdisease: A meta-analysis of randomized controlled trials.

BACKGROUND: Second-generation drug-eluting stents (DESs) have become increasingly popular devices for patients with saphenous vein graft (SVG) disease. Second-generation DESs were designed to have more safety and efficacy than first-generation DES, but clinical outcomes in SVG disease remain conflicting. METHODS AND RESULTS: Randomized controlled trials (RCTs) were identified when comparing second- versus first-generation DESs in SVG disease. The main endpoint was all-cause death. The time of follow-up was at least 30days. The secondary endpoints were major adverse cardiovascular events (MACEs), target vessel revascularization (TVR), target lesion revascularization (TLR), myocardial infarction (MI), and stent thrombosis. These endpoints were assessed at 30days, 12months and 24months. Four RCTs with 1077 SVG patients undergoing the implantation of DES were collected in the current meta-analysis. As a result, second-generation DES-treated patients had the significantly lower MACE rates at 12months (P=0.03; OR: 0.69, 95% CI: 0.49,0.97). No differences in two groups were seen in all-cause death, MI, TVR, stent thrombosis and TLR. CONCLUSIONS: Our limited evidence indicated that, second-generation DES in SVG patients, compared with first-generation DES, offered similar levels of safety, but were more effective than the former one.

[Blood vessel tissue engineering: seeding vascular smooth muscle cells and endothelial cells sequentially on biodegradable scaffold in vitro].

OBJECTIVE: To evaluate the effect of seeding vascular smooth muscle cells and endothelial cells sequentially on biodegradable scaffold in vitro. METHODS: Venous endothelial cells and smooth muscle cells of artery were isolated from the umbilical cord of newborn and cultured in vitro. The cultured arterial smooth muscle cells and cultured endothelial cells were seeded on the polyglycolic acid and polylactide (PLGA) nonwoven mesh as tissue scaffolds respectively (group A and group B). And cultured endothelial cells were seeded on the scaffold already seeded with smooth muscle cells sequentially to construct vascular patch (group C). One month after cultivation the patches of the 3 groups underwent HE staining and microscopic examination and scanning electron microscopy. Immunohistochemistry was used to examine the existence of actin and factor VIII-related antigen, secreted by endothelial cells, in the cells. The levels of endothelin and 6-Keto-PGF1alpha in the culture solution were examined by means of radioimmunology so as to measure the endothelial function. Pure culture solution was used as blank control (group D). RESULTS: Microscopy showed that cells were fused into patch in the group C. HE staining showed that the smooth muscle cells were embedded into the PLGA scaffold and grew in multiple layers covered by a layer of endothelial cells on the surface. The types of cells could be identified by immunohistochemical procedure. The levels of endothelin and 6-Keto-PGF1alpha in the culture solution were 229 pg/ml +/- 34 pg/ml and 402 pg/ml +/- 108 pg/ml respectively in the group C, and 200 pg/ml +/- 31 pg/ml and 336 pg/ml +/- 121 pg/ml in the group B, both significantly higher than those in the groups A and D (blank control group, all P < 0.05 or P < 0.05). CONCLUSION: Tissue engineering blood vessel with normal morphological and functional characters to a certain degree can be constructed through seeding cultured vascular smooth muscle cells and endothelial cells sequentially on PLGA scaffold.

[Relationship of the HSG gene single nucleotide polymorphism and hypertension].

OBJECTIVE: To investigate the single nucleotide polymorphism (SNP) of the novel hyperplasia suppressor gene (HSG) to uncover the relationship between HSG SNP and hypertension. METHODS: Totally, 74 normotensive people (38 men and 36 women), 51 patients with essential hypertension (27 men and 24 women) and 20 hypertensive patients with family history of essential hypertension (9 men and 11 women) were chosen, with mean ages of (54 +/- 8) years, (57 +/- 8) years and (38 +/- 22) years, respectively. Peripheral venous blood specimen was collected from each of them and then DNA was extracted. The right primers were designed for DNA amplification with PCR. Each of the PCR-products from different groups was sequenced by ABI PRISM 377-DNA sequencer and their base components and characteristics of the same fragment were compared each other. RESULTS: Blood levels of creatinine (CRE) and urea nitrogen (BUN) were significantly higher in the hypertensives than in the normotensives (P < 0.01). Systolic and diastolic blood pressures were significantly higher in the hypertensives and the hypertensives with family history of essential hypertension than in the normotensives (P < 0.01 and P < 0.05). There existed three kinds of SNP in the HSG 12th intron (1q82139 G/A, 82153C/G and 82273G/-), and there was significant difference in 1q82153C/G and 82273G/- SNP between the hypertensives and normotensives (P < 0.05 and P < 0.01) and between the hypertensives with family history and the normotensives (P < 0.01 and P < 0.01). And, the similar difference in C/G allele and G deletion could be found in different populations. Moreover, the CC genetype of 1q82153 was common in the population (P < 0.01) and G deletion was more common in Chinese Han people with family history of essential hypertension. There was no significant difference existed in 1q82139 G/A mutation among the three groups. CONCLUSIONS: Measurements of renal function indicators (CRE and BUN) could probably reflect earlier advance of hypertension and damage to target organs. There existed three kinds of mutation in the 12th intron of the HSG 1q82139 G/A, 82153 C/G and 82273 G/-. The 1q82139 G/A could be a nonsense mutation and there was significant difference in the 1q82153 C/G and 1q82273 G/- SNP and gene frequencies between different Chinese Han populations, which could be independent risk factors for essential hypertension.

G-protein beta 3 subunit polymorphisms and essential hypertension: a case-control association study in northern Han Chinese.

OBJECTIVE: To explore the association between the three polymorphisms [ C825T, C1429T and G(-350)A] of the gene encoding the G protein beta 3 subunit (GNB3) and hypertension by performing a case-control study in the northern Han Chinese population. METHODS: We recruited 731 hypertensive patients and 673 control subjects (the calculated power value was > 0.8). Genotyping was performed to identify C825T, C1429T and G(-350)A polymorphisms using the TaqMan assay. Comparisons of allelic and genotypic frequencies between cases and controls were made by using the chi-square test. Logistic regression analyses were performed to investigate the relationships between the three polymorphisms of GNB3 gene under different genetic models (additive, dominant and recessive models). RESULTS: The genotype distribution and allele frequencies of C825T, C1429T and G(-350)A polymorphisms did not differ significantly between hypertensive patients and control subjects, either when the full sample was assessed, or when the sample was stratified by gender. No significant association was observed between C825T, C1429T and G(-350)A polymorphisms and the risk of essential hypertension in any genetic model. Linkage disequilibrium was only detected between C825T and C1429T polymorphisms. Haplotype analyses observed that none of the three estimated haplotypes significantly increased the risk of hypertension. CONCLUSIONS: Our study suggested that the GNB3 gene polymorphisms [C825T, C1429T and G(-350)A] were not significantly associated with essential hypertension in northern Han Chinese population.

Screening the proteins that interact with calpain in a human heart cDNA library using a yeast two-hybrid system.

Calpain, a cytosolic cysteine protease, requires calcium ions for activity. It has been reported that calpain is involved in the degradation of myofibrillar and neurofilament proteins, and the activation of phosphorylase b kinase and protein kinase C. More recently, calpain was shown to participate in apoptosis. In order to understand the calpain-related signal transduction pathway and its changes during hypertrophy, and especially in hypertension, we screened a human heart cDNA library to find proteins that interact with calpain. 1) Using PCR we amplified the full-length, domain II, domain III and domain IV cDNA of calpain (calcium-activated neutral protease, CANP) I large subunit respectively. 2) Then the fragments were cloned into pGBKT7 vector, resulting in 4 bait expression constructs (pGBKT7-CANP, pGBKT7-CANP II, pGBKT7-CANP III, and pG BKT7-CANP IV). 3) After 4 bait vectors were transformed into AH109 by the lithium acetate-mediated method, AH109/pGBKT7-CANP, AH109/pGBKT7-CANP II, AH109/pGBKT7-CANP III, and AH109/pGBKT7-CANP IV were obtained, respectively. 4) After the human heart cDNA library was sequentially transformed into AH109/ pGBKT7-CANP, 1000-1200 positive clones were grown on SD/Trp-Leu-Ade-His-. Only 150 positive clones were obtained through a colony-lift filter assay to detect beta-galactosidase activity. 5) Total 105 clones among above 150 positive clones were eliminated through that the duplicate, pseudopositive and autoactive detection, respectively. 6) Finally, sequencing eliminated clones with a wrong open reading frame (ORF). Eight clones were cancelled with wrong ORF. The remaining 37 positive clones were analyzed using BLAST software available on the Internet and classified as follows: 1. enzymes or proteins related to signal transduction in the cell; 2. contraction proteins 3. matrix proteins 4. unknown proteins. 7) In order to determine which domain of the calpain I large subunit was involved in the interaction with these real clones, the 37 clones were transformed into AH109/pGBKT7-CANP II, AH109/pGBKT7-CANP III or AH109/pGBKT7-CANP IV. Among these 37 clones, 29 clones could interact with domain II, 5 clones could interact with domain III and 6 clones could interact with domain IV. Thus, we successfully constructed 4 bait expression vectors, pGBKT7-CANP, pGBKT7-CANP II, pGBKT7-CANP III and pGBKT7-CANP IV, and obtained 37 real positive clones that interacted with the calpain I large subunit by screening a human heart cDNA library using pGBKT7-CANP as bait. Among them, 29 clones could interact with domain II of the calpain I large subunit, where the active site of calpain is located. Additional studies will be needed to clarify the calpain-related signal transduction pathway in greater detail.