Targeted Metabolomics Study of Human Plasma Revealed Activation of the Cytochrome P450 Epoxygenase/Epoxide Hydrolase Axis in Patients with IgA Nephropathy.

IgA nephropathy (IgAN) is the most common primary glomerulonephritis and a leading cause of chronic kidney disease. The pathogenic mechanism of IgAN remains largely unknown and thus a specific therapeutic target is lacking. Here, we reported that the cytochrome P450 (CYP) epoxygenase/epoxide hydrolase (EH) axis was activated in the patients and is likely a therapeutic target for IgAN. Specifically, quantitative profiling of the plasma from IgAN patients and healthy controls revealed significant changes in plasma levels of CYP/EH-mediated lipid epoxides and diols. Subsequently, CYP2C8, CYP2C18, CYP2J2, EPHX1, and EPHX2 were found to be significantly increased in whole blood cells at mRNA levels from the IgAN patients when compared with those of healthy controls. Immunohistochemical analysis showed that all five CYPs and two EHs were upregulated in the kidney tissue from IgAN patients when compared with normative renal tissue, but the expression locations of the proteins were different with most of them. Treatment of HK-2 cells with IgA1 increased cell viability, compressed cell apoptosis, and increased the protein levels of CYP2C9, EPHX1, and EPHX2. All the results agreed that CYPs/EHs axis is likely the prophylactic and therapeutic target for IgAN, providing IgAN patients with a new intervention strategy.

Inhibition of soluble epoxide hydrolase attenuates a high-fat diet-mediated renal injury by activating PAX2 and AMPK.

A high-fat diet (HFD) causes obesity-associated morbidities involved in macroautophagy and chaperone-mediated autophagy (CMA). AMPK, the mediator of macroautophage, has been reported to be inactivated in HFD-caused renal injury. However, PAX2, the mediator for CMA, has not been reported in HFD-caused renal injury. Here we report that HFD-caused renal injury involved the inactivation of Pax2 and Ampk, and the activation of soluble epoxide hydrolase (sEH), in a murine model. Specifically, mice fed on an HFD for 2, 4, and 8 wk showed time-dependent renal injury, the significant decrease in renal Pax2 and Ampk at both mRNA and protein levels, and a significant increase in renal sEH at mRNA, protein, and molecular levels. Also, administration of an sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea, significantly attenuated the HFD-caused renal injury, decreased renal sEH consistently at mRNA and protein levels, modified the renal levels of sEH-mediated epoxyeicosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs) as expected, and increased renal Pax2 and Ampk at mRNA and/or protein levels. Furthermore, palmitic acid (PA) treatment caused significant increase in Mcp-1, and decrease in both Pax2 and Ampk in murine renal mesangial cells (mRMCs) time- and dose-dependently. Also, 14(15)-EET (a major substrate of sEH), but not its sEH-mediated metabolite 14,15-DHET, significantly reversed PA-induced increase in Mcp-1, and PA-induced decrease in Pax2 and Ampk. In addition, plasmid construction revealed that Pax2 may positively regulate Ampk transcriptionally in mRMCs. This study provides insights into and therapeutic target for the HFD-mediated renal injury.

Epoxide metabolites of arachidonate and docosahexaenoate function conversely in acute kidney injury involved in GSK3ß signaling.

Acute kidney injury (AKI) causes severe morbidity and mortality for which new therapeutic strategies are needed. Docosahexaenoic acid (DHA), arachidonic acid (ARA), and their metabolites have various effects in kidney injury, but their molecular mechanisms are largely unknown. Here, we report that 14 (15)-epoxyeicosatrienoic acid [14 (15)-EET] and 19 (20)-epoxydocosapentaenoic acid [19 (20)-EDP], the major epoxide metabolites of ARA and DHA, respectively, have contradictory effects on kidney injury in a murine model of ischemia/reperfusion (I/R)-caused AKI. Specifically, 14 (15)-EET mitigated while 19 (20)-EDP exacerbated I/R kidney injury. Manipulation of the endogenous 19 (20)-EDP or 14 (15)-EET by alteration of their degradation or biosynthesis with selective inhibitors resulted in anticipated effects. These observations are supported by renal histological analysis, plasma levels of creatinine and urea nitrogen, and renal NGAL. The 14 (15)-EET significantly reversed the I/R-caused reduction in glycogen synthase kinase 3ß (GSK3ß) phosphorylation in murine kidney, dose-dependently inhibited the hypoxia/reoxygenation (H/R)-caused apoptosis of murine renal tubular epithelial cells (mRTECs), and reversed the H/R-caused reduction in GSK3ß phosphorylation in mRTECs. In contrast, 19 (20)-EDP dose-dependently promoted H/R-caused apoptosis and worsened the reduction in GSK3ß phosphorylation in mRTECs. In addition, 19 (20)-EDP was more metabolically stable than 14 (15)-EET in vivo and in vitro. Overall, these epoxide metabolites of ARA and DHA function conversely in I/R-AKI, possibly through their largely different metabolic stability and their opposite effects in modulation of H/R-caused RTEC apoptosis and GSK3ß phosphorylation. This study provides AKI patients with promising therapeutic strategies and clinical cautions.

The prognostic value of oxidative stress and inflammation in Chinese hemodialysis patients.

BACKGROUND: There is limited information about oxidative stress and inflammation on the mortality of Chinese hemodialysis (HD) patients. SUBJECTS AND METHODS: A total of 177 HD patients and 35 healthy controls were enrolled. Their demographic information, clinical characteristics, oxidant and inflammation markers were compared. Multivariate Cox regression analysis was used to assess the risk factors for mortality. RESULTS: Twenty-seven (15.3%) HD patients died during the one-year follow-up. The mean age, age ≥70 years, serum level of cardiac troponin T (cTnT), malondialdehyde (MDA) > 5 nmol/L, as well as CRP >10 mg/L and the level of interleukin (IL)-6 were significantly different between the nonsurvival and survival HD patients. Multivariate Cox's regression analysis identified age, age ≥70 years, cTnT, and IL-6 were independent predictors of mortality in HD patients. CONCLUSIONS: Age, age ≥70 years, cTnT, and IL-6 were independent predictors of mortality in Chinese HD patients. Elevated IL-6 level, instead of MDA, was predictive of poor outcome in Chinese hemodialysis patients.

Carbon Monoxide Releasing Molecule Accelerates Reendothelialization after Carotid Artery Balloon Injury in Rat.

OBJECTIVE: This study was aimed to investigate the effects of carbon monoxide releasing molecule (CORM-2), a novel carbon monoxide carrier, on the reendothelialization of carotid artery in rat endothelial denudation model. METHODS: Male rats subjected to carotid artery balloon injury were treated with CORM-2, inactive CORM-2 (iCORM-2) or dimethyl sulfoxide (DMSO). The reendothelialization capacity was evaluated by Evans Blue dye and the immunostaining with anti-CD31 antibody. The number of circulating endothelial progenitor cells (EPCs) was detected by flow cytometry. The proliferation, migration, and adhesion of human umbilical vein endothelial cells (HUVECs) were assessed by using [3H]thymidine, Boyden chamber and human fibronectin respectively. The expressions of protein were detected by using western blot analysis. RESULTS: CORM-2 remarkably accelerated the re-endothelialization 5 d later and inhibited neointima formation 28 d later. In addition, the number of peripheral EPCs significantly increased in CORM-2-treated rats than that in iCORM-2 or DMSO-treated rats after 5 d later. In vitro experiments, CORM-2 significantly enhanced the proliferation, migration and adhesion of HUVECs. The levels of Akt, eNOS phosphorylation, and NO generation in HUVECs were also much higher in CORM-2 treated group. Blocking of PI3K/Akt/eNOS signaling pathway markedly suppressed the enhanced migration and adhesion of HUVECs induced by CORM-2. CONCLUSION: CORM-2 could promote endothelial repair, and inhibit neointima formation after carotid artery balloon injury, which might be associated with the function changes of HUVECs regulated by PI3K/Akt/eNOS pathway.

[Impact of insulin resistance on prognosis in non-diabetic patients with acute coronary syndromes].

OBJECTIVE: To evaluate the impact of insulin resistance (IR) on prognosis in non-diabetic acute coronary syndrome patients. METHODS: In this prospective study, we enrolled 332 non-diabetic patients suffering from acute coronary syndrome. The patients were divided into three groups by HOMA-IR which calculated by formula: low HOMA-IR group (HOMA-IR < 2), 44 cases; moderate HOMA-IR group (2 ≤ HOMA2-IR < 6), 99 cases; high HOMA-IR group (HOMA ≥ 6) with HOMA index, 179 cases. The in-hospital medical records of patients were compared, and all patients were followed up for one year after discharge. RESULTS: Incidence of hypertension (P = 0.013), dyslipidemia (P < 0.001), faster resting heart rate (P < 0.001) and number of triple vessel coronary artery disease (P = 0.017) in high HOMA-IR group were significantly higher than in low and moderate HOMA-IR group. During follow-up, the major end-point events increased in proportion to IR grade: 64.3% (26/44) in the high HOMA-IR group, 54.7% (52/99) in moderate HOMA-IR group and 41.3% (74/199) in low HOMA-IR group (P = 0.034). Multivariable logistic regression analysis showed that high sensitivity C reactive protein (OR = 1.012, 95%CI:1.002-1.022, P = 0.022), HOMA-IR (OR = 1.250, 95%CI:1.043-1.497, P = 0.015) , triple vessel coronary artery disease (OR = 5.914, 95%CI:2.947-11.868, P < 0.001) , ischemic changes on ECG (OR = 5.495, 95%CI:2.925-10.324, P < 0.001) and low left ventricular ejection fraction (LVEF ≤ 40%) (OR = 13.205, 95%CI:5.000-34.661, P < 0.001) were independent risk factor for major end-point events during follow-up. CONCLUSIONS: Increased insulin resistance is linked with poor prognosis of non-diabetic patients with acute coronary syndrome.

Metabolomics analysis of human plasma reveals decreased production of trimethylamine N-oxide retards the progression of chronic kidney disease.

BACKGROUND AND PURPOSE: Chronic kidney disease (CKD) is a global public health problem and one of the leading causes of all-cause mortality. However, the pathogenic mechanisms and intervention methods for CKD progression are not fully understood. EXPERIMENTAL APPROACH: Plasma from patients with uraemia and from healthy controls (n = 30 per group) was analysed with LC-MS/MS-based non-targeted metabolomics to identify potential markers of uraemia. These potential markers were validated in the same cohort and a second cohort (n = 195) by quantitative analysis of the markers, using LC-MS/MS. The most promising marker was identified by correlation analysis and further validated using HK-2 cells and mouse models. KEY RESULTS: Trimethylamine N-oxide (TMAO) was identified as a promising marker among the 18 potential markers found in the first cohort, and it was optimally correlated with renal function of CKD patients in the second cohort. Treatment of HK-2 cells with TMAO decreased cell viability and up-regulated expression of α-smooth muscle actin. In mice, a TMAO-containing diet decreased kidney mass and increased protein expression of α-smooth muscle actin. Also, control of TMAO production by inhibiting its biosynthetic pathway with 3,3-dimethyl-1-butanol or disrupting gut microbiota function with an antibiotic cocktail, attenuated renal injury in a murine model of CKD. CONCLUSION AND IMPLICATIONS: Our data show that decreased TMAO production could be a new strategy to attenuate the progression of renal injury in CKD.

Role of CD2-associated protein in albumin overload-induced apoptosis in podocytes.

Proteinuria is a well-established exacerbating factor of chronic kidney diseases. However, the harmful effects of protein overload on podocytes and the underlying mechanisms are still poorly understood. In the present study, we examined the effects of high concentrations of albumin on podocytes and investigated the role of CD2AP (CD2-associated protein) in albumin overload-induced podocyte apoptosis. Conditionally immortalized mouse podocytes were cultured in vitro and treated with different concentrations of BSA. In addition, CD2AP eukaryotic expression vector or siRNA (small interfering RNA) was transfected into podocytes before they were exposed to BSA. Podocyte apoptosis, expressions of active caspase-3 (p17) and CD2AP, and the distribution of F-actin cytoskeleton were detected by flow cytometry, Western-blot analysis and fluorescent staining respectively. It was found that exposure of podocytes to BSA induced podocyte apoptosis in a concentration-dependent manner that was accompanied by up-regulation of active caspase-3, the disruption of F-actin cytoskeleton, and decreased expression of CD2AP. Transfection of CD2AP eukaryotic expression vector into podocytes increased CD2AP expression, partially restored F-actin distribution, blocked active caspase-3 expression and inhibited podocyte apoptosis. In contrast, transfection of CD2AP siRNA deteriorated the above changes induced by BSA. It is concluded that protein overload induces podocyte apoptosis via the down-regulation of CD2AP and subsequent disruption of cytoskeleton of podocytes, and CD2AP may play an important role in protein overload-induced podocyte injury.

The Downregulation of ADAM17 Exerts Protective Effects against Cardiac Fibrosis by Regulating Endoplasmic Reticulum Stress and Mitophagy.

BACKGROUND: A disintegrin and metalloproteinase 17 (ADAM17) is a transmembrane protein that is widely expressed in various tissues; it mediates the shedding of many membrane-bound molecules, involving cell-cell and cell-matrix interactions. We investigated the role of ADAM17 within mouse cardiac fibroblasts (mCFs) in heart fibrosis. METHODS: mCFs were isolated from the hearts of neonatal mice. Effects of ADAM17 on the differentiation of mCFs towards myofibroblasts and their fibrotic behaviors following induction with TGF-ß1 were examined. The expression levels of fibrotic proteins, such as collagen I and α-SMA, were assessed by qRT-PCR analysis and western blotting. Cell proliferation and migration were measured using the CCK-8 and wound healing assay. To identify the target gene for ADAM17, the protein levels of the components of endoplasmic reticulum (ER) stress and the PINK1/Parkin pathway were assessed following ADAM17 silencing. The effects of ADAM17 silencing or treatment with thapsigargin, a key stimulator of acute ER stress, on mCFs proliferation, migration, and collagen secretion were also examined. In vivo, we used a mouse model of cardiac fibrosis established by left anterior descending artery ligation; the mice were administered oral gavage with a selective ADAM17 inhibitor (TMI-005) for 4 weeks after the operation. RESULTS: We found that the ADAM17 expression levels were higher in fibrosis heart tissues and TGF-ß1-treated mCFs. The ADAM17-specific siRNAs decreased TGF-ß1-induced increase in the collagen secretion, proliferation, and migration of mCFs. Knockdown of ADAM17 reduces the activation of mCFs by inhibiting the ATF6 branch of ER stress and further activating mitophagy. Moreover, decreased ADAM17 expression also ameliorated cardiac fibrosis and improved heart function. CONCLUSIONS: This study highlights that mCF ADAM17 expression plays a key role in cardiac fibrosis by regulating ER stress and mitophagy, thereby limiting fibrosis and improving heart function. Therefore, ADAM17 downregulation, within the physiological range, could exert protective effects against cardiac fibrosis.

LncRNA H19 governs mitophagy and restores mitochondrial respiration in the heart through Pink1/Parkin signaling during obesity.

Maintaining proper mitochondrial respiratory function is crucial for alleviating cardiac metabolic disorders during obesity, and mitophagy is critically involved in this process. Long non-coding RNA H19 (H19) is crucial for metabolic regulation, but its roles in cardiac disorders, mitochondrial respiratory function, and mitophagy during obesity are largely unknown. In this study, palmitic acid (PA)-treated H9c2 cell and Lep-/- mice were used to investigate cardiac metabolic disorders in vitro and in vivo, respectively. The effects of H19 on metabolic disorders, mitochondrial respiratory function, and mitophagy were investigated. Moreover, the regulatory mechanisms of PA, H19, mitophagy, and respiratory function were examined. The models tested displayed a reduction in H19 expression, respiratory function and mitochondrial number and volume, while the expression of mitophagy- and Pink1/Parkin signaling-related proteins was upregulated, as indicated using quantitative real-time PCR, Seahorse mitochondrial stress test analyzer, transmission electron microscopy, fluorescence indicators and western blotting. Forced expression of H19 helped to the recoveries of respiratory capacity and mitochondrial number while inhibited the levels of mitophagy- and Pink1/Parkin signaling-related proteins. Pink1 knockdown also attenuated PA-induced mitophagy and increased respiratory capacity. Mechanistically, RNA pull-down, mass spectrometry, and RNA-binding protein immunoprecipitation assays showed that H19 could hinder the binding of eukaryotic translation initiation factor 4A, isoform 2 (eIF4A2) with Pink1 mRNA, thus inhibiting the translation of Pink1 and attenuation of mitophagy. PA significantly increased the methylation levels of the H19 promoter region by upregulation Dnmt3b methylase levels, thereby inhibiting H19 transcription. Collectively, these findings suggest that DNA methylation-mediated the downregulation of H19 expression plays a crucial role in cardiomyocyte or H9c2 cells metabolic disorders and induces cardiac respiratory dysfunction by promoting mitophagy. H19 inhibits excessive mitophagy by limiting Pink1 mRNA translation, thus alleviating this cardiac defect that occurs during obesity.

Plasma D-dimer as a predictor of intraluminal thrombus burden and progression of abdominal aortic aneurysm.

AIM: Intraluminal thrombus (ILT) is presented in most abdominal aortic aneurysms (AAAs) and is suggested to promote AAA expansion. D-dimer, a breakdown product in the thrombus remodeling, may have prognostic value for AAA. This study investigated the interrelation between plasma D-dimer level, ILT volume, AAA size and progression. MAIN METHODS: This was a retrospective observational study that involved 181 patients with infra-renal AAA. They were divided into small and large AAA groups according to AAA diameter. 24 of them had repeated abdominal computed tomography angiography (CTA) scan and were divided into slow-growing and fast-growing AAA groups according to the median value of AAA growth rate. Baseline and follow-up plasma D-dimer level, maximum diameter of AAA, total infra-renal aortic volume and ILT volume were analyzed. KEY FINDINGS: Plasma D-dimer level was positively correlated with ILT volume (R = 0.382, P < 0.001) and maximum diameter of AAA (R = 0.442, P < 0.001). Increasing value of plasma D-dimer was positively associated with the accelerated growth rate of AAA (R = 0.720, P < 0.01). ILT volume showed positive correlation with maximum diameter (R = 0.859, P < 0.001) and growth rate of AAA (R = 0.490, P < 0.05). After adjusting the baseline ILT volume, the positive correlations remained to be statistically significant between plasma D-dimer level and AAA size (R = 0.200, P < 0.05), as well as increasing value of plasma D-dimer and growth rate of AAA (R = 0.642, P < 0.05). SIGNIFICANCE: Plasma D-dimer level reflected ILT burden in AAAs. Plasma D-dimer level and ILT volume were positively correlated with AAA size. Increasing value of plasma D-dimer and baseline ILT volume could be predictors of AAA progression.

Pharmacodynamic changes of platelet reactivity status in patients with chronic kidney disease after coronary artery stenting.

OBJECTIVES: This study was to evaluate platelet reactivity over time among patients with chronic kidney disease (CKD) receiving standard dose of clopidogrel after percutaneous coronary intervention (PCI). The effect of CYP2C19 loss-of-function genotypes on platelet reactivity was also determined. METHODS: Patients with CKD (n = 138) on maintenance dose of clopidogrel after PCI were enrolled. Platelet reactivity was assessed by measuring P2Y12 reaction units (PRU) with VerifyNow P2Y12 assay, and platelet reactivity index (PRI) with flow cytometric using vasodilator-stimulated phosphoprotein (VASP) at baseline and 2 weeks later, respectively. The genotypes of CYP2C19 were also measured concurrently. RESULTS: The proportion of patients with high platelet reactivity (HPR) ranged from 23.2% to 59.4%, and almost 1 in 5 patients had a dual conversion between HPR and non-HPR status. Patients carrying CYP2C19 loss-of-function genotypes showed a higher platelet reactivity than non-carriers, but with an undetermined HPR status between the first and second visits. The individual switch of HPR to non-HPR status existed in both loss-of-function genotype carriers and non-carriers. CONCLUSIONS: HPR conversions occur in a significant proportion of CKD patients with maintenance doses of clopidogrel treatment post-PCI, and this conversion was not confined to CYP2C19 loss-of-function genotype carriers. Risk stratification for treatment adjustment in personalized antiplatelet therapy should be investigated in future research.

Atrial septal defect in a patient with congenital disorder of glycosylation type 1a: a case report.

BACKGROUND: Atrial septal defect often become more severe when encountered in genetic syndromes. Congenital disorder of glycosylation type 1a is an inherited metabolic disorder associated with mutations in PMM2 gene and can affect almost all organs. Cardiac abnormalities vary greatly in congenital disorder of glycosylation type 1a and congenital heart defects have already been reported, but there is little knowledge about the effect of this inherited disorder on an existing congenital heart defect. Herein we report for the first time on a baby with congenital disorder of glycosylation type 1a with atrial septal defect and make a comparison of changes in atrial septal defect by follow-ups to the age of 3. CASE PRESENTATION: Our patient was an 8-month-old Han Chinese boy. At the initial visit, he presented with recurrent lower respiratory infection, heart murmur, psychomotor retardation, inverted nipples, and cerebellar atrophy. Echocardiography revealed a 8 mm secundum atrial septal defect with left-to-right shunt (Qp/Qs ratio 1.6). Enzyme testing of phosphomannomutase 2 demonstrated decreased levels of phosphomannomutase 2 activities in fibroblasts. Whole exon sequencing showed he was heterozygous for a frameshift mutation (p.I153X) and a missense mutation (p.I132T) in PMM2 gene. The diagnosis of congenital disorder of glycosylation type 1a with atrial septal defect was issued. Now, he is 3-years old at the time of this writing, with the development of congenital disorder of glycosylation type 1a (cerebellar atrophy become more severe and the symptom of nystagmus emerged), the size of atrial septal defect increased to 10 mm and the Qp/Qs ratio increased to 1.9, which suggested exacerbation of the atrial septal defect. Congenital heart defect-associated gene sequencing is then performed and shows there are no pathogenic mutations, which suggested intrinsic cardiac factors are not the cause of exacerbation of the atrial septal defect in our patient and it is reasonable to assume congenital disorder of glycosylation type 1a can worsen the situation of the existing atrial septal defect. CONCLUSIONS: This report highlights the view that congenital disorders of glycosylation type 1a should be excluded when faced with congenital heart defect with cerebellar atrophy or neurodevelopmental delay, especially when the situation of congenital heart defect becomes more and more severe.

Overexpression of the ß2AR gene improves function and re-endothelialization capacity of EPCs after arterial injury in nude mice.

BACKGROUND: Proliferation and migration of endothelial progenitor cells (EPCs) play important roles in restoring vascular injuries. ß2 adrenergic receptors (ß2ARs) are widely expressed in many tissues and have a beneficial impact on EPCs regulating neoangiogenesis. The aim of the present study was to determine the effect of overexpressing ß2ARs in infused peripheral blood (PB)-derived EPCs on the re-endothelialization in injured vessels. METHODS: Induction of endothelial injury was performed in male nude mice that were subjected to wire-mediated injury to the carotid artery. Human PB-derived EPCs were transfected with an adenovirus serotype 5 vector expressing ß2AR (Ad5/ß2AR-EPCs) and were examined 48 h later. ß2AR gene expression in EPCs was detected by real-time polymerase chain reaction and Western blot analysis. In vitro, the proliferation, migration, adhesion, and nitric oxide production of Ad5/ß2AR-EPCs were measured. Meanwhile, phosphorylated Akt and endothelial nitric oxide synthase (eNOS), which are downstream of ß2AR signaling, were also elevated. In an in vivo study, CM-DiI-labeled EPCs were injected intravenously into mice subjected to carotid injury. After 3 days, cells recruited to the injury sites were detected by fluorescent microscopy, and the re-endothelialization was assessed by Evans blue dye. RESULTS: In vitro, ß2AR overexpression augmented EPC proliferation, migration, and nitric oxide production and enhanced EPC adhesion to endothelial cell monolayers. In vivo, when cell tracking was used, the number of recruited CM-DiI-labeled EPCs was significantly higher in the injured zone in mice transfused with Ad5/ß2AR-EPCs compared with non-transfected EPCs. The degree of re-endothelialization was also higher in the mice transfused with Ad5/ß2AR-EPCs compared with non-transfected EPCs. We also found that the phosphorylation of Akt and eNOS was increased in Ad5/ß2AR-EPCs. Preincubation with ß2AR inhibitor (ICI118,551), Akt inhibitor (ly294002), or eNOS inhibitor (L-NAME) significantly attenuated the enhanced in vitro function and in vivo re-endothelialization capacity of EPCs induced by ß2AR overexpression. CONCLUSIONS: The present study demonstrates that ß2AR overexpression enhances EPC functions in vitro and enhances the vascular repair abilities of EPCs in vivo via the ß2AR/Akt/eNOS pathway. Upregulation of ß2AR gene expression through gene transfer may be a novel therapeutic target for endothelial repair.

Interleukin 18 and extracellular matrix metalloproteinase inducer cross-regulation: implications in acute myocardial infarction.

Circulating interleukin-18 (IL-18) is thought to promote atherosclerosis and cardiovascular complications such as plaque rupture. Atherosclerosis is also characterized by smooth muscle cell migration, a consequence of extracellular matrix (ECM) degradation regulated by metalloproteinases (MMPs). Because extracellular matrix metalloproteinase inducer (EMMPRIN) has been shown to promote plaque instability by inducing ECM degradation and MMP synthesis, we investigated whether a cross-regulatory interaction exists between IL-18 and EMMPRIN in human monocytes. EMMPRIN levels in monocytes were markedly greater in 20 patients with acute myocardial infarction (AMI) compared with 20 patients with stable angina pectoris or 20 healthy volunteers (control group). The levels of IL-18 and MMP-9 in serum were also significantly greater in the AMI group in comparison with the other 2 groups. IL-18 levels positively correlated with increased levels of EMMPRIN in monocytes. In vitro, the expression of EMMPRIN was increased in monocytes cultured with IL-18, and IL-18 secretion was augmented in monocytes cultured with EMMPRIN. Gene silencing of EMMPRIN by small interfering RNA reduced monocyte secretion of both IL-18 and MMP-9. In the present study, cross-regulation between IL-18 and EMMPRIN in monocytes was demonstrated. This interaction may amplify the inflammatory cascade and be responsible for increased monocytic MMP-9 serum levels in atherosclerosis, contributing to atherosclerotic plaque destabilization and subsequent AMI.

Triple antithrombotic therapy versus double antiplatelet therapy after percutaneous coronary intervention with stent implantation in patients requiring chronic oral anticoagulation: a meta-analysis.

BACKGROUND: Whether an addition of OAC to double antiplatelet therapy for patients with an indication of chronic oral anticoagulation undergoing PCI-S may improve clinical outcomes is still debated. This meta-analysis aimed to update and re-compare the benefits and risks of triple antithrombotic therapy (TT) with double anti-platelet therapy (DAPT) after in patients who requiring oral anticoagulation after percutaneous coronary interventions with stenting (PCI-s). METHODS: Ten reports of observational retrospective or prospective studies were retrieved, including a total of 6296 patients, follow-up period ranging from 1 year to 2 years. RESULTS: Baseline characteristics were similar in both groups. The main finding of this study is the overall incidence of major adverse cardiovascular events (MACE), myocardial infarction (MI) and stent thrombosis was comparable between two groups. Patients with TT was associated with significant reduction in ischemic stroke (OR: 0.27; 95%CI: 0.13 - 0.57; P = 0.0006) as compared to DAPT. We reaffirmed triple therapy significantly increased the risk of major bleeding (OR: 1.47; 95%CI: 1.22 - 1.78; P < 0.0001) and minor bleeding (OR: 1.55; 95%CI: 1.07 - 2.24; P = 0.02). CONCLUSIONS: Triple therapy is more efficacious in reducing the occurrence of ischemic stroke in PCI-s patients with an indication of chronic oral anticoagulation (OAC), compared with DAPT. However, it significantly increased major and minor risk of bleeding. It is imperative that further prospective randomized controlled trials are required to defne the best therapeutic strategy for patients with an indication of chronic OAC undergoing PCI-s.

Poor coronary collateral vessel development in patients with mild to moderate renal insufficiency.

BACKGROUND: The development of coronary collaterals is crucial to survival through acute ischemia. Mild to moderate loss of renal function has been suggested to play a role in this event, but evidential data are scarce. The aim of this study was to investigate the relationship between mild to moderate renal insufficiency and coronary collateral development in patients with chronic total coronary artery occlusion. METHODS AND RESULTS: A total of 83 patients with mild to moderate loss of renal function (30 mL/min/1.73 m(2) ≤ eGFR < 90 mL/min/1.73 m(2)) with chronic total coronary artery occlusion were included in our study. The collateral circulation was graded according to Rentrop classification and the function of collateral circulation was graded according to Werner collateral connection (CC) grades. Compared to patients with good collateral circulation (Rentrop = 2,3), eGFR was found to be lower in those patients with poor coronary collateral circulation (Rentrop = 0,1) (63.30 ± 10.51 vs. 54.13 ± 10.56, P = 0.02). eGFR was also found to be lower in poorly functioning coronary collateral circulation (CC = 0,1) than in efficiently functioning coronary collateral circulation (CC = 2) (55.22 ± 9.98 vs. 66.28 ± 9.16, P = 0.03). Multiple logistic regression analysis showed that low eGFR was independently associated with poor coronary collateral circulation (Rentrop = 0,1, 95% CI, 0.09-1.09, P = 0.044) and poor function of coronary collateral circulation (CC = 0,1, 95% CI, 0.02-0.17, P = 0.02). CONCLUSIONS: Lower eGFR is associated with poorer coronary collateral vessel development in patients experiencing mild to moderate renal insufficiency. Moreover, eGFR represents an independent factor affecting coronary collateral vessel development.

Increased expression of granulocyte colony-stimulating factor mediates mesenchymal stem cells recruitment after vascular injury.

BACKGROUND: Recent studies indicate that bone marrow-derived cells may significantly contribute to atherosclerosis, post-angioplasty restenosis and transplantation-associated vasculopathy. The responsible bone marrow (BM) cells and mechanisms regulating the mobilization of these cells are currently unclear. The purpose of this study was to investigate the expression of granulocyte colony-stimulating factor (G-CSF) on injured arteries and its effects on mesenchymal stem cells (MSCs) differentiation into vascular smooth muscle cells (VSMCs) in the process of vascular remodeling. METHODS: Balloon-mediated vascular injury was established in female rats (n = 100) which received radioprotective whole female BM cells by tail vein injection and male MSCs through a tibial BM injection after lethal irradiation. The injured and contralateral carotid arteries were harvested at 3, 7, 14 and 28 days after treatment. RESULTS: Morphometric analysis indicated that intima to media area-ratio (I/M ratio) significantly increased at 28 days, 0.899 ± 0.057 (P < 0.01), compared with uninjured arteries. Combining fluorescence in situ hybridization (FISH) and immunohistochemical analysis showed that a significant number of the neointimal cells derived from MSCs, (45.2 ± 8.5)% at 28 days (P = 0.01), compared with (23.5 ± 6.3)% at 14 days. G-CSF was induced in carotid arteries subject to balloon angioplasty (fold mRNA change = 8.67 ± 0.63 at three days, relative G-CSF protein = 0.657 ± 0.011 at three days, P < 0.01, respectively, compared with uninjured arteries). G-CSF was chemotactic for MSCs but did not affect the differentiation of MSCs into smooth-muscle-like cells. CONCLUSION: Increased expression of G-CSF by injured arteries plays an essential role in contribution to recruitment and homing of MSCs to the site of the arterial lesion.