Zinc attenuates monocrotaline-induced pulmonary hypertension in rats through upregulation of A20.

Pulmonary hypertension (PH) is characterized by excessive proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), in which inflammatory signaling caused by activation of the NF-κB pathway plays an important role. A20 is an important negative regulator of the NF-κB pathway, and zinc promotes the expression of A20 and exerts a protective effect against various diseases (e.g. COVID19) by inhibiting the inflammatory signaling. The role of A20 and intracellular zinc signaling in PH has been explored, but the extracellular zinc signaling is not well understood, and whether zinc has protective effects on PH is still elusive. Using inductively coupled plasma mass spectrometry (ICP-MS), we studied the alteration of trace elements during the progression of monocrotaline (MCT)-induced PH and found that serum zinc concentration was decreased with the onset of PH accompanied by abnormalities of other three elements, including copper, chromium, and magnesium. Zinc chloride injection with the dosage of 5 mg/kg intraperitoneally partially corrected this abnormality and inhibited the progression of PH. Zinc supplementation induced the expression of A20 in lung tissue and reduce the inflammatory responses. In vitro, zinc supplementation time-dependently upregulated the expression of A20 in PASMCs, therefore correcting the excessive proliferation and migration of cells caused by hypoxia. Using genetically encoded-FRET based zinc probe, we found that these effects of zinc ions are not achieved by entering cells, but most likely by activating cell surface zinc receptor (ZnR/GPR39). These results provide the first evidence of the effectiveness of zinc supplementation in the treatment of PH.

Comparative Analysis of Single-Path and Multipath Adrenal Venous Sampling in Primary Aldosteronism.

Objective: To evaluate the safety and efficacy of adrenal venous sampling (AVS) via the cubital vein and femoral vein synchronously. Methods: A total of 200 patients with primary aldosteronism admitted to the First Hospital of Fujian Medical University were enrolled and randomly divided into a single-path AVS group (SP, N = 108) and a multipath AVS group (MP, N = 92). We analyzed the clinical characteristics, intubation success rate, procedure cost, total fluoroscopy time, complications, contrast dosage, and the number of catheters selected during AVS. A planar quadrant system was established to mark the direction of the adrenal opening, with the intersection of the right renal vein and the inferior vena cava defined as the origin. In digital subtraction angiography images, the RAV opening located in the 0-3 o'clock direction was the first quadrant (I), and the 3-6 o'clock direction was the third quadrant (III). Results: There was no statistical difference between the two groups at baseline. Multipath AVS had a significantly higher success rate of right-sided intubation than single-path AVS (success rate of right-sided intubation/%: SP 87.96 vs MP 95.65, P = 0.043). Total fluoroscopy time was significantly reduced (fluoroscopy time/min: SP 9.80 ± 4.07 vs MP 7.42 ± 3.48, P = 0.024) and the cost of the procedure was markedly lower (cost/yuan: SP 3,900.93 ± 1,191.12 vs MP 3,378.26 ± 399.40, P < 0.001). There was no significant difference in postoperative complications between the two groups. In the group I, the procedure was completed mainly with an MPA catheter (catheter selection/%: MPA 98.19 vs TIG 17.65, P < 0.001). In the group III, TIG catheters were used more frequently (catheter selection/%: MPA 1.81 vs TIG 82.35, P < 0.001). Conclusion: Multipath AVS via the cubital vein and femoral vein improves the success rate of AVS with comparable safety compared to single-path AVS. When the RAV is opened in the III quadrant, the TIG catheter improves the cannulation success rate. The multipath AVS method provides more catheter options. Patients diagnosed with PA at the First Hospital of Fujian Medical University from December 2019 to December 2021 were included. The collection of medical records of the included population was approved by the ethics committee (approval number: [2021] 311). This was a cross-sectional study in which some patients were treated surgically and some were treated with superselective adrenal artery embolization (SAAE). We conducted a cohort study of patients treated with SAAE. ClinicalTrials.gov Protocol Registration and Results System (PRS) receipt release date: January 11, 2022. This trial is registered with NCT05188872.

A nomogram based on endothelial function and conventional risk factors predicts coronary artery disease in hypertensives.

BACKGROUND: There is currently a lack of a precise, concise, and practical clinical prediction model for predicting coronary artery disease (CAD) in patients with essential hypertension (EH). This study aimed to construct a nomogram to predict CAD in patients with EH based on flow-mediated dilation (FMD) of brachial artery and traditional risk factors. METHODS: Clinical data of 1752 patients with EH were retrospectively collected. High-resolution vascular ultrasound was used to detect FMD in all patients at the Fujian Hypertension Research Institute, China. Patients were divided into two groups, i.e. training group (n = 1204, from August 2000 to December 2013) and validation group (n = 548, from January 2014 to May 2016) according to the time of enrollment. Independent predictors of CAD were analyzed by multivariable logistic regression in the training group, and a nomogram was constructed accordingly. Finally, we evaluated the discrimination, calibration, and clinical applicability of the model using the area under curve (AUC) of receiver operating characteristic analysis, calibration curve combined with Hosmer-Lemeshow test, and decision curve, respectively. RESULTS: There were 263 (21.8%) cases of EH combined with CAD in the training group. Multivariate logistic regression showed that FMD, age, duration of EH, waist circumference, and diabetes mellitus were independent influencing factors for CAD in EH patients. Smoking which was close to statistical significance (P = 0.062) was also included in the regression model to increase the accuracy. Ultimately, the nomogram for predicting CAD in EH patients was constructed according to above predictors after proper transformation. The AUC values of the training group and the validation group were 0.799 (95%CI 0.770-0.829) and 0.836 (95%CI 0.787-0.886), respectively. Calibration curve and Hosmer-Lemeshow test showed that the model had good calibration (training group: χ2 = 0.55, P = 0.759; validation group: χ2 = 1.62, P = 0.446). The decision curve also verified the clinical applicability of the nomogram. CONCLUSION: The nomogram based on FMD and traditional risk factors (age, duration of EH disease, smoking, waist circumference and diabetes mellitus) can predict CAD high-risk group among patients with EH.

Increased Plasma Homocysteine Levels Are Associated with Left Ventricular Hypertrophy in Hypertensive Patients with Normal Renal Function.

INTRODUCTION: Renal function has an important bearing on plasma homocysteine levels. Plasma homocysteine is related to left ventricular hypertrophy (LVH). However, it remains unclear whether the association between plasma homocysteine levels and LVH is influenced by renal function. This study aimed to investigate relationships among left ventricular mass index (LVMI), plasma homocysteine levels, and renal function in a population from southern China. METHODS: A cross-sectional study was performed in 2,464 patients from June 2016 to July 2021. Patients were divided into three groups based on gender-specific tertiles of homocysteine levels. LVMI ≥115 g/m2 for man or ≥95 g/m2 for woman was defined as LVH. RESULTS: LVMI and the percentage of LVH were increased, while estimated glomerular filtration rate (eGFR) was decreased with the increase in homocysteine levels, both significantly. Multivariate stepwise regression analysis showed that eGFR and homocysteine were independently associated with LVMI in patients with hypertension. No correlation was observed between homocysteine and LVMI in patients without hypertension. Stratified by eGFR, further analysis confirmed homocysteine was independently associated with LVMI (ß = 0.126, t = 4.333, p < 0.001) only in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), not with 60≤ eGFR <90 mL/(min·1.73 m2). Multivariate logistic regression indicated that in hypertensive patients with eGFR ≥90 mL/(min·1.73 m2), the patients in high tertile of homocysteine levels had a nearly twofold increased risk of occurring LVH compared with those in low tertile (high tertile: OR = 2.780, 95% CI: 1.945-3.975, p < 0.001). CONCLUSION: Plasma homocysteine levels were independently associated with LVMI in hypertensive patients with normal eGFR.

The identification and verification of hub genes associated with pulmonary arterial hypertension using weighted gene co-expression network analysis.

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, with complex etiology, difficult treatment and poor prognosis. The objective of this study was to investigate the potential biomarkers for PAH based on bioinformatics analysis. METHODS: The GSE117261 datasets were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified by screening PAH patients and controls. Then the DEGs were analyzed using a Weighted Gene Co-expression Network Analysis (WGCNA) and the key modules were determined, and to further explore their potential biological functions via Gene Ontology analysis (GO), Kyoto Encyclopedia of Genes and Genomes Pathway analysis (KEGG), and Gene Set Enrichment Analysis (GSEA). Moreover, Protein-protein interaction (PPI) networks were constructed to identify hub gene candidates in the key modules. Finally, real-time quantitative polymerase chain reaction was supplied to detect the expressions of hub genes in human pulmonary arterial smooth cells treated with cobalt chloride (COCl2) which was used to mimic hypoxia. RESULTS: There were 2299 DEGs identified. WGCNA indicated that yellow module was the key one correlated with PAH. GO and KEGG analysis demonstrated that genes in the yellow module were mainly enriched in 'Pathways in cancer'. GSEA revealed that 'HALLMARK_MYC_TARGETS_V1' was remarkably enriched in PAH. Based on the PPI network, vascular endothelial growth factor A, proto-oncogene receptor tyrosine kinase (KIT), PNN interacting serine and arginine rich protein (PNISR) and heterogeneous nuclear ribonucleoprotein H1 (HNRNPH1) were identified as the hub genes. Additionally, the PCR indicated that the elevated expressions of PNISR and HNRNPH1 were in line with the bioinformatics analysis. ROC analysis determined that PNISR and HNRNPH1 may be potential biomarkers to provide better diagnosis of PAH. CONCLUSION: PNISR and HNRNPH1 were potential biomarkers to diagnosis PAH. In summary, the identified DEGs, modules, pathways, and hub genes provide clues and shed light on the potential molecular mechanisms of PAH.

The zinc transporter ZIP12 regulates monocrotaline-induced proliferation and migration of pulmonary arterial smooth muscle cells via the AKT/ERK signaling pathways.

BACKGROUND: The zinc transporter ZIP12 is a membrane-spanning protein that transports zinc ions into the cytoplasm from the extracellular space. Recent studies demonstrated that upregulation of ZIP12 is involved in elevation of cytosolic free zinc and excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs) induced by hypoxia. However, the expression of ZIP12 and its role in pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) in rats have not been evaluated previously. The aim of this study was to investigate the effect of ZIP12 on the proliferation and migration of PASMCs and its underlying mechanisms in MCT-induced PAH. METHODS: A PAH rat model was generated by intraperitoneal injection of 20 mg/kg MCT twice at one-week intervals. PASMCs were isolated from the pulmonary arteries of rats with MCT-induced PAH or control rats. The expression of ZIP12 and related molecules was detected in the lung tissues and cells. A ZIP12 knockdown lentivirus and an overexpressing lentivirus were constructed and transfected into PASMCs derived from PAH and control rats, respectively. EdU assays, wound healing assays and Western blotting were carried out to explore the function of ZIP12 in PASMCs. RESULTS: Increased ZIP12 expression was observed in PASMCs derived from MCT-induced PAH rats. The proliferation and migration of PASMCs from PAH rats were significantly increased compared with those from control rats. These results were corroborated by Western blot analysis of PCNA and cyclin D1. All these effects were significantly reversed by silencing ZIP12. Comparatively, ZIP12 overexpression resulted in the opposite effects as shown in PASMCs from control rats. Furthermore, selective inhibition of AKT phosphorylation by LY294002 abolished the effect of ZIP12 overexpression on enhancing cell proliferation and migration and partially suppressed the increase in ERK1/2 phosphorylation induced by ZIP12 overexpression. However, inhibition of ERK activity by U0126 resulted in partial reversal of this effect and did not influence an increase in AKT phosphorylation induced by ZIP12 overexpression. CONCLUSIONS: ZIP12 is involved in MCT-induced pulmonary vascular remodeling and enhances the proliferation and migration of PASMCs. The mechanism of these effects was partially mediated by enhancing the AKT/ERK signaling pathways.

Zinc-mediated activation of CREB pathway in proliferation of pulmonary artery smooth muscle cells in pulmonary hypertension.

BACKGROUND: Transcription factor CREB is involved in the development of pulmonary hypertension (PH). However, little is known about the role and regulatory signaling of CREB in PH. METHODS: A series of techniques, including bioinformatics methods, western blot, cell proliferation and luciferase reporter assay were used to perform a comprehensive analysis of the role and regulation of CREB in proliferation of pulmonary artery smooth muscle cells (PASMCs) in PH. RESULTS: Using bioinformatic analysis of the differentially expressed genes (DEGs) identified in the development of monocrotaline (MCT)- and hypoxia-induced PH, we found the overrepresentation of CRE-containing DEGs. Western blot analysis revealed a sustained increase in total- and phosphorylated-CREB in PASMCs isolated from rats treated with MCT. Similarly, an enhanced and prolonged serum-induced CREB phosphorylation was observed in hypoxia-pretreated PASMCs. The sustained CREB phosphorylation in PASMCs may be associated with multiple protein kinases phosphorylated CREB. Additionally, hierarchical clustering analysis showed reduced expression of the majority of CREB phosphatases in PH, including regulatory subunits of PP2A, Ppp2r2c and Ppp2r3a. Cell proliferation analysis showed increased PASMCs proliferation in MCT-induced PH, an effect relied on CREB-mediated transcriptional activity. Further analysis revealed the raised intracellular labile zinc possibly from ZIP12 was associated with reduced phosphatases, increased CREB-mediated transcriptional activity and PASMCs proliferation. CONCLUSIONS: CREB pathway was overactivated in the development of PH and contributed to PASMCs proliferation, which was associated with multiple protein kinases and/or reduced CREB phosphatases and raised intracellular zinc. Thus, this study may provide a novel insight into the CREB pathway in the pathogenesis of PH. Video abstract.

Transcription factor CREB plays an important role in the development of pulmonary hypertension (PH). However, paradoxical roles have been reported in the pathogenesis of PH, and the regulatory mechanisms of CREB activation in pulmonary artery smooth muscle cells (PASMCs) proliferation remained unknown. In this study, we showed that CRE-containing genes were overrepresented among the differentially expressed genes in experimental PH, which resulted from the sustained activation of CREB pathway. The sustained activation of CREB pathway may be associated with the activation of multiple protein kinases that positively regulate CREB and down-regulation of numerous phosphatases involved in CREB dephosphorylation. Additionally, we found that the proliferation of PAMSCs was dependent on the CREB-mediated transcriptional activity in experimental PH. Moreover, the raised intracellular labile zinc possibly from ZIP12 may be associated with reduced protein phosphatases, increased CREB-mediated transcriptional activity and PASMCs proliferation. Collectively, we found CREB-mediated transcriptional activity in the proliferation of PASMCs in PH, which may be associated with multiple protein kinases and/or reduced phosphatases and elevated intracellular zinc. This study may reveal a critical role of zinc-mediated activation of CREB pathway in the proliferation of PASMCs, thus providing a more comprehensive understanding of CREB pathway in the pathogenesis of PH.

Transcriptomic analysis identifies Toll-like and Nod-like pathways and necroptosis in pulmonary arterial hypertension.

Inflammation and immunity play a causal role in the pathogenesis of pulmonary vascular remodelling and pulmonary arterial hypertension (PAH). However, the pathways and mechanisms by which inflammation and immunity contribute to pulmonary vascular remodelling remain unknown. RNA sequencing was used to analyse the transcriptome in control and rats injected with monocrotaline (MCT) for various weeks. Using the transcriptional profiling of MCT-induced PAH coupled with bioinformatics analysis, we clustered the differentially expressed genes (DEGs) and chose the increased expression patterns associated with inflammatory and immune response. We found the enrichment of Toll-like receptor (TLR) and Nod-like receptor (NLR) pathways and identified NF-κB-mediated inflammatory and immune profiling in MCT-induced PAH. Pathway-based data integration and visualization showed the dysregulated TLR and NLR pathways, including increased expression of TLR2 and NLRP3, and their downstream molecules. Further analysis revealed that the activation of TLR and NLR pathways was associated with up-regulation of damage-associated molecular patterns (DAMPs) and RIPK3-mediated necroptosis was involved in the generation of DAMPs in MCT-induced PAH. Collectively, we identify RIPK3-mediated necroptosis and its triggered TLR and NLR pathways in the progression of pulmonary vascular remodelling, thus providing novel insights into the mechanisms underlying inflammation and immunity in the pathogenesis of PAH.

Role of 20-hydroxyeicosatetraenoic acid in pulmonary hypertension and proliferation of pulmonary arterial smooth muscle cells.

OBJECTIVE: To investigate the level of 20-Hydroxyeicosatetraenoic acid (20-HETE) in model of pulmonary hypertension (PH) and its effect on the proliferation of pulmonary arterial smooth muscle cells (PASMCs). METHODS: Twenty male Sprague-Dawley rats were randomly divided into two groups, including control group and PH group. PH was induced by intra-peritoneal injection of 20 mg/kg monocrotaline (MCT) twice in a week in 10 rats, and control rats were given equal amount of saline. Mean pulmonary arterial pressure (mPAP), right ventricular hypertrophy index (RVHI) and pulmonary vascular remodeling index (WA%, WT%) were assessed at the week 4. The levels of 20-HETE were analysed by liquid chromatography tandem-mass spectrometry (LC-MS/MS). EdU test was used to determine the proliferation of PASMCs. Intracellular levels of reactive oxygen species (ROS) were detected using DCFH-DA dye. RESULTS: (1) Prominent right ventricular hypertrophy and pulmonary vascular remodeling were verified in PH rats; (2) 20-HETE levels in lung tissue and serum were significantly lifted in PH rats; (3) Increased 20-HETE levels in cell culture supernatants were significantly noted in hypoxia condition; (4) Proliferation of PASMCs was induced by 20-HETE and hypoxia, and was inhibited by HET0016; (5) Production of ROS was elevated by 20-HETE and hypoxia, and was reduced by HET0016; CONCLUSION: Vascular remodeling was demonstrated in PH rats. 20-HETE levels were significantly increased in PH rats and under hypoxia condition. PASMCs proliferation and ROS production were elevated by 20-HETE and could be inhibited by HET0016, a specific inhibitor of 20-HETE. Taken together, changes in the level of 20-HETE may be related to the excessive proliferation of PASMCs in PH rats.

Relationship between components of metabolic syndrome and arterial stiffness in Chinese hypertensives.

Background: Subjects with metabolic syndrome showed increased risk of cardiovascular events. We investigated the relationship between components of metabolic syndrome and arterial stiffness in Chinese hypertensives.Method: 680 subjects (aged 58.44 ± 11.67 years, male 63.53%, hypertension 65.00%) were divided into five groups based on the number of known components of metabolic syndrome (MSCs) according to the criteria of 2010 Chinses Guidelines for Prevention and Management of Hypertension (0MSCs: n= 86; 1MSCs: n= 153; 2MSCs: n= 201; 3MSCs: n= 148; 4/5MSCs: n= 92.). Body weight, height, waist circumference, blood pressure and clinical biochemical tests were measured. Carotid-femoral pulse wave velocity (cfPWV) was measured using a non-invasive automatic device (Complior Analysis, France).Results: The level of cfPWV was significantly increased with the increasing number of MSCs (8.20 ± 1.54 vs 8.72 ± 1.48 vs 9.34 ± 1.77 vs 9.64 ± 1.86 vs 9.91 ± 2.19 m/s, P<0.05). In subjects with hypertension (n= 442), cfPWV was higher than those without hypertension (n= 238) (9.59 ± 1.90 vs 8.49 ± 1.50 m/s, P<0.05) . Stepwise multiple regression analysis revealed that age, gender, the number of MSCs, heart rate as well as serum uric acid level were determinants for cfPWV (P<0.05). In the subgroups stratified by age, systolic blood pressure correlated with cfPWV in hypertensives under 55 years old, while in non-hypertensives the correlation was found after 60 years old.Conclusion: The arterial stiffness became significant with the increasing of the metabolic components numbers, which was independent of age, gender and blood pressure. And the presence of hypertension played the most important role in the progress of arterial stiffness even compared with age.

CPT1 regulates the proliferation of pulmonary artery smooth muscle cells through the AMPK-p53-p21 pathway in pulmonary arterial hypertension.

Abnormal proliferation of pulmonary artery smooth muscle cells (PASMCs) plays a dominant role in the development of pulmonary arterial hypertension (PAH). Some studies and our previous work found that disturbance of fatty acid metabolism existed in PAH. However, the mechanistic link between fatty acid catabolism and cell proliferation remains elusive. Here, we identified an essential role and signal pathway for the key rate-limiting enzyme of mitochondrial fatty acid ß-oxidation, carnitine palmitoyltransferase (CPT) 1, in regulating PASMC proliferation in PAH. We found that CPT1 was highly expressed in rat lungs and pulmonary arteries in monocrotaline-induced PAH, accompanied by decreased adenosine triphosphate (ATP) production and downregulation of the AMPK-p53-p21 pathway. Platelet-derived growth factor (PDGF)-BB upregulated the expression of CPT1 in a dose- and time-dependent manner. PASMC proliferation and ATP production induced by PDGF-BB were partly reversed by the CPT1 inhibitor etomoxir (ETO). The overexpression of CPT1 in PASMCs also promoted proliferation and ATP production and subsequently inhibited the phosphorylation of AMPK, p53, as well as p21 in PASMCs. Furthermore, AMPK was activated by ETO, which increased the expression of p53 and p21, and the proportion of cells in the cell cycle G2/M phase in response to PDGF-BB stimulation in PASMCs. Our work reveals a novel mechanism of CPT1 regulating PASMC proliferation in PAH, and regulation of CPT1 may be a potential target for therapeutic intervention in PAH.

Low-Grade Albuminuria Is Associated with Left Ventricular Hypertrophy and Diastolic Dysfunction in Patients with Hypertension.

INTRODUCTION: Microalbuminuria is a risk factor for cardiovascular morbidity and mortality in hypertensive patients. However, the relationship between low-grade albuminuria, a higher level of albuminuria below microalbuminuria threshold, and hypertension-related organ damage is unclear. Left ventricular (LV) hypertrophy (LVH) is well recognized to be a subclinical organ damage of hypertension, and LV diastolic dysfunction is also reported to be an early functional cardiac change of hypertension that predicts heart failure. The present study aimed to investigate the association of low-grade albuminuria with LVH and LV diastolic dysfunction in hypertensive patients. METHODS: This cross-sectional observational clinical study was retrospectively performed in 870 hypertensive patients admitted to our hospital. Urinary albumin to creatinine ratio (UACR) was calculated to assess the levels of albuminuria: macroalbuminuria (≥300 mg/g), microalbuminuria (≥30 mg/g, but <300 mg/g), and normal albuminuria (<30 mg/g). Low-grade albuminuria was defined as sex-specific highest tertile within normal albuminuria (8.1-29.6 mg/g in males and 11.8-28.9 mg/g in females). LVH and LV diastolic dysfunction were identified as recommended by American Society of Echocardiography. RESULTS: Of the 870 patients, 765 (87.9%) had normal albuminuria, 77 (8.9%) had microalbuminuria, and 28 (3.2%) had macroalbuminuria. Percentage of LVH and LV diastolic dysfunction was increased with ascending UACR. UACR was independently associated with LVH and LV diastolic dysfunction, even in patients with normal albuminuria. Multivariable logistic regression showed that the patients with the highest tertile within normal albuminuria had nearly 80% increase in LVH and nearly 60% increase in LV diastolic dysfunction (adjusted OR for LVH 1.788, 95% CI 1.181-2.708, p = 0.006; adjusted OR for LV diastolic dysfunction 1.567, 95% CI 1.036-2.397, p = 0.034). After further stratification analyses in patients with normal albuminuria, it was shown that this independent association persisted in female patients, those who were younger than 70 years old, and those with duration of hypertension <15 years. CONCLUSION: Low-grade albuminuria was associated with LVH and LV diastolic dysfunction in hypertensive patients, especially in patients younger than 70 years old, and those with duration of hypertension <15 years.

TRPM7 regulates angiotensin II-induced sinoatrial node fibrosis in sick sinus syndrome rats by mediating Smad signaling.

Sinoatrial node fibrosis is involved in the pathogenesis of sinus sick syndrome (SSS). Transient receptor potential (TRP) subfamily M member 7 (TRPM7) is implicated in cardiac fibrosis. However, the mechanisms underlying the regulation of sinoatrial node (SAN) fibrosis in SSS by TRPM7 remain unknown. The aim of this study was to investigate the role of angiotensin II (Ang II)/TRPM7/Smad pathway in the SAN fibrosis in rats with SSS. The rat SSS model was established with sodium hydroxide pinpoint pressing permeation. Forty-eight rats were randomly divided into six groups: normal control (ctrl), sham operation (sham), postoperative 1-, 2-, 3-, and 4-week SSS, respectively. The tissue explant culture method was used to culture cardiac fibroblasts (CFs) from rat SAN tissues. TRPM7 siRNA or encoding plasmids were used to knock down or overexpress TRPM7. Collagen (Col) distribution in SAN and atria was assessed using PASM-Masson staining. Ang II, Col I, and Col III levels in serum and tissues or in CFs were determined by ELISA. TRPM7, smad2 and p-smad2 levels were evaluated by real-time PCR, and/or western blot and immunohistochemistry. SAN and atria in rats of the SSS groups had more fibers and higher levels of Ang II, Col I and III than the sham rats. Similar findings were obtained for TRPM7 and pSmad2 expression. In vitro, Ang II promoted CFs collagen synthesis in a dose-dependent manner, and potentiated TRPM7 and p-Smad2 expression. TRPM7 depletion inhibited Ang II-induced p-Smad2 expression and collagen synthesis in CFs, whereas increased TRPM7 expression did the opposite. SAN fibrosis is regulated by the Ang II/TRPM7/Smad pathway in SSS, indicating that TRPM7 is a potential target for SAN fibrosis therapy in SSS.

A meta-analytical comparison of atenolol with angiotensin-converting enzyme inhibitors on arterial stiffness, peripheral blood pressure and heart rate in hypertensive patients.

OBJECTIVES: This meta-analysis of randomized parallel controlled trials was designed to compare the efficacy of atenolol with angiotensin-converting enzyme inhibitors (ACEIs) in changing pulse wave velocity (PWV), peripheral blood pressure and heart rate (HR) among patients with essential hypertension. METHODS: This study was conducted according to the PRISMA guideline. Data collection was independently completed by two investigators. Statistical analyses were completed by Stata software (v12.0). RESULTS: Eight clinical trials were meta-analyzed in this study. Overall changes in PWV (weighted mean difference or WMD = 0.068, 95% confidence interval or CI: -0.487 to -0.623, P = 0.811) and peripheral systolic blood pressure (PSBP) (WMD = -1.281 mmHg, 95% CI: -6.936 to 4.375, P = 0.657) did not differ significantly between atenolol and ACEIs treatment. Relative to ACEIs, atenolol had a more favorable impact on peripheral diastolic blood pressure (PDBP) (WMD = -1.912 mmHg, 95% CI: -3.732 to -0.091, P = 0.040) and HR (WMD = -9.23 bpm, 95% CI: -12.53 to -5.93, P < 0.001). In stratified analyses, particularly by follow-up period, atenolol was observed to be superior over ACEIs within early 3-month treatment in PSBP (WMD = -4.097 mmHg, 95% CI: -6.589 to -1.605, P = 0.001), PDBP (WMD = -6.802 mmHg, 95% CI: -8.517 to -5.087, P < 0.001) and HR (WMD = -14.242 bpm, 95% CI: -16.427 to -12.058, P = 0.028), without heterogeneity (I2 = 0.0%). There were low probabilities of publication bias for all comparisons. CONCLUSIONS: Our findings demonstrate that atenolol and ACEIs were equally effective in reducing PWV and PSBP, while atenolol was superior over ACEIs in improving PDBP and HR, especially within short-term treatment.

Combined treatment of irbesartan and diltiazem ameliorates endothelium dependent vasodilatation in hypertensives.

OBJECTIVE: Endothelial function is of prognostic importance for hypertensives. The aim of this study was to investigate the effects of irbesartan combined with diltiazem on the endothelium-dependent vasodilatation in essential hypertensive (EH) patients in China. METHODS: A total of 150 Chinese hypertensives aged from 40 to 80 years old were assigned into three groups: irbesartan treated(150 mg/d, n = 46), diltiazem treated (90 mg/d, n = 51), and combined therapy group (irbesartan 150 mg/d+ diltiazem 90 mg/d, n = 53). Forty age and gender-matched normotensives without clinical manifestation of cardiovascular diseases served as controls. High-resolution ultrasonography was used to assess flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) in the brachial artery. Left ventricular mass index (LVMI) was calculated. Fibrinogen (Fg) was determined by Clauss and Stago auto analyzer. Blood pressure was measured using mercury sphygmomanometers. RESULTS: FMD and NMD were lower in combined treatment group compared to normotensives before treatment at baseline [FMD(8.39 ± 3.04)% vs. (11.21 ± 3.88)%, NMD (13.96 ± 5.71)% vs. (16.78 ± 6.22)%, p < 0.05]. FMD was improved significantly after the combined therapy [(10.72 ± 3.46)% vs. (8.39 ± 3.04)%, p < 0.05]. No significant difference in NMD was found among three hypertensive groups after therapy. Moreover, FMD increased significantly with the prolongation of treatment. After stratification of age, FMD in younger EH patients under 65 years old was markedly increased after treatment within 1 year, whereas FMD in EH patients over 65 years old showed a significant increase after 3-year therapy. In addition, LVMI was reduced in hypertensives after combined therapy [(99.1 ± 17.9) g/m2 vs. (90.6 ± 16.2) g/m2, p < 0.01]. Logistic analysis showed that age was an important risk factor for FMD. CONCLUSIONS: Combined therapy of irbesartan with diltiazem ameliorated endothelial function.

Lowered circulating apelin is significantly associated with an increased risk for hypertension: A meta-analysis.

BACKGROUND AND OBJECTIVE: Apelin is a bioactive peptide manifesting a potent vasodilatory property. In this meta-analysis, we aimed to investigate for the first time whether circulating apelin differed significantly between hypertensive patients and normotensive controls. METHODS: Both PubMed and Embase were searched for eligible articles. Eligibility evaluation and data collection were done independently by two investigators. Weighted mean difference (WMD) with 95% confidence interval (CI) was calculated under random-effects model by STATA. RESULTS: Ten studies were synthesized finally, including 1610 patients and 1105 controls. Overall analysis revealed that circulating apelin was significantly lowered in patients than in controls (WMD = -39.85 pg/mL, 95% CI: -65.56 to -14.15; P = 0.002), with significant heterogeneity (I2 = 89.4%). By race, patients had lower circulating apelin than controls in Caucasian populations (WMD = -79.82 pg/mL, 95% CI: -105.80 to -53.85; P < 0.001), without heterogeneity (I2=0.0%), while no significance was observed in Chinese and African-Americans. Further grouping studies by source of controls found a significant reduction in circulating apelin in studies with hospital-based controls (WMD = -96.28 pg/mL, 95% CI: -129.67 to -62.88; P < 0.001) (I2 = 49.4%), but not in studies with population-based controls. CONCLUSIONS: Via a meta-analysis of 10 studies and on 2715 subjects, our findings demonstrated that lowered circulating apelin was significantly associated with an increased risk for hypertension, especially in Caucasian populations.

Preventive treatment with atorvastatin ameliorates endothelial dysfunction of small pulmonary arteries in monocrotaline-induced pulmonary hypertensive rats.

This study examined the effects of preventive atorvastatin (Ator) treatment on vasodilatation of small pulmonary arteries (SPAs) in monocrotaline (MCT)-induced pulmonary hypertensive rats. SD rats were randomly assigned to: normal control (Ctr), pulmonary arterial hypertension (PAH), PAH treated with 5 mg/kg/d Ator (LAtor), or 10 mg/kg/d Ator (HAtor). PAH was induced by MCT injection (40 mg/kg, i.p.). Mean pulmonary artery pressure (mPAP), right ventricular hypertrophy index (RVHI%), endothelium-dependent relaxations (EDdRs), and endothelium-independent relaxations (EDiRs) were determined. Four weeks after MCT injection, mPAP was higher in PAH group compared to that in Ctr group, and this effect was suppressed by Ator treatment (PAH: 32.19 ± 0.91 mm Hg vs. LAtor: 19.13 ± 1.01 mm Hg, HAtor: 17.55 ± 0.20 mm Hg, p < 0.05). Similar trend of changes in RVHI% was found in the same way. EDdRs of SPA rings in PAH group were markedly decreased 2 and 4 weeks after MCT injection, while in Ator treated groups, the impairment can only be detected 4 weeks after MCT injection. There were no differences in EDiRs among all groups 1 week after MCT injection. However, 2 weeks and 4 weeks after MCT injection, EDiRs were significantly impaired, while in HAtor and LAtor groups, EDiR was only impaired 4 weeks but not 2 weeks after MCT injection. Preventive treatment with atorvastatin for 2 weeks ameliorated endothelium-dependent and endothelium-independent vasodilative dysfunction in small pulmonary artery rings of MCT-induced PAH rats. It suggests that MCT-induced damage of endothelial function was progressing, and Ator was only beneficial in the early stage of MCT-induced PAH.

Adipose-derived stem cells attenuate pulmonary arterial hypertension and ameliorate pulmonary arterial remodeling in monocrotaline-induced pulmonary hypertensive rats.

We investigated the effect of adipose-derived stem cells (ADSCs) transplantation effects on structural remodeling and pulmonary artery pressure in monocrotaline (MCT)-induced pulmonary hypertensive rats. In the first experiment, 32 male Sprague-Dawley (SD) rats were randomly divided into four groups (n = 8/group): 3 ADSCs treated groups and normal control (Ctrl). ADSCs were administered through the left jugular vein at 10(5), 10(6) and 10(7) cells, respectively, and a cell density of 10(6)cells/ml was shown to be optimal. The GFP-tagged ADSCs were identified in the lungs and differentiated into endothelial-like cells. In the second experiment, 96 male SD rats were randomly divided into three groups (n = 32/group): Ctrl, MCT-induced pulmonary arterial hypertension (PAH), and PAH treated with ADSCs (ADSCs). Two weeks post-MCT administration, the ADSCs group received 1 × 10(6) ADSCs via the external jugular vein. Compared to PAH rats, mean pulmonary arterial pressure was decreased in rats at 1, 2, and 3 weeks after ADSCs-treatment (18.63 ± 2.15 mmHg versus 24.53 ± 2.90 mmHg; 23.07 ± 2.84 mmHg versus 33.18 ± 2.30 mmHg; 22.98 ± 2.34 mmHg versus 36.38 ± 3.28 mmHg, p < 0.05). Meanwhile, the right heart hypertrophy index (36.2 1 ± 4.27% versus 41.01 ± 1.29%; 39.47 ± 4.02% versus 48.75 ± 2 .13%; 41.02 ± 0.9% versus 50.52 ± 1.49%, p < 0.05, respectively), ratio of wall/lumen thickness, as well as the wall/lumen area were significantly reduced in PAH rats at these time points following ADSCs-treatment, as compared with untreated PAH rats. In summary, ADSCs may colonize the pulmonary arteries, attenuate pulmonary arterial hypertension and ameliorate pulmonary arterial remodeling.

Silencing heat shock protein 27 (HSP27) inhibits the proliferation and migration of vascular smooth muscle cells in vitro.

The objective of this study was to examine the role of heat shock protein 27 (HSP27) in proliferation and migration of vascular smooth muscle cells (VSMCs). Three complementary DNA sequences targeting rat HSP27 gene were designed, synthesized, and subcloned into lentiviral vector. The interfering efficiency was detected by reverse transcriptase-polymerase chain reaction and Western blot. Methyl thiazolyl tetrazolium bromide assay was used for examining cell proliferation. F-actin polymerization was detected by FITC-Phalloidin staining using confocal microscopy. Modified Boyden chamber technique was used to assess VSMCs migration. The recombinant lentivirus containing RNAi targeting HSP27 gene significantly inhibited expression of HSP27 at both mRNA and protein levels. The interfering efficiencies of pNL-HSP27-EGFP-1, pNL-HSP27-EGFP-2, and pNL-HSP27-EGFP-3 were 71 %, 77 %, and 43 %, respectively. Reorganization of actin stimulated by PDGF-BB was markedly blocked by pretreatment with pNL-HSP27-EGFP-2. Proliferation and migration rates of VSMCs induced by PDGF-BB were inhibited by 30.8 % and 45.6 %, respectively, by pNL-HSP27-EGFP-2 (all P < 0.01). To conclude, these data indicate that HSP27 may regulate the proliferation, actin reorganization, and the migration of VSMCs. RNAi targeting at HSP27 may be a potential approach for inhibition of cell migration involved in pathogenesis of proliferative vascular diseases.

Effect of early endothelial function improvement on subclinical target organ damage in hypertensives.

Endothelial dysfunction is acknowledged as a marker for subclinical target organ damage (STOD) in hypertension, though its therapeutic potential has not yet been clarified. This study assessed whether early endothelial function improvement (EEFI) reduced STOD in patients with essential hypertension (EH). We conducted a retrospective cohort analysis of 456 EH patients initially free from STOD. Endothelial function was assessed using brachial artery flow-mediated dilation (FMD), with values ≤ 7.1% indicating dysfunction. Patients were initially categorized by endothelial status (dysfunction: n = 180, normal: n = 276), and further divided into improved or unimproved groups based on changes within three months post-enrollment. During a median follow-up of 25 months, 177 patients developed STOD. The incidence of STOD was significantly higher in patients with initial dysfunction compared to those with normal function. Kaplan-Meier analysis indicated that the improved group had a lower cumulative incidence of STOD compared to the unimproved group (p < 0.05). Multivariable Cox regression confirmed EEFI as an independent protective factor against STOD in EH patients (p < 0.05), regardless of their baseline endothelial status, especially in those under 65 years old, non-smokers, and with low-density lipoprotein cholesterol levels ≤ 3.4 mmol/L. In conclusion, EEFI significantly reduces STOD incidence in EH patients, particularly in specific subgroups, emphasizing the need for early intervention in endothelial function to prevent STOD.