Timing of prescription of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in patients hospitalized for acute heart failure with reduced/mildly reduced ejection fraction: a retrospective analysis.

Although angiotensin-converting enzyme inhibitors (ACEis) and angiotensin II receptor blockers (ARBs) play critical roles in the treatment of heart failure with reduced or mildly reduced ejection fraction (HFrEF/HFmrEF; left-ventricular ejection fraction ≤ 50%), the ideal timing for initiation in patients with acute heart failure (AHF) is unclear. We sought to clarify the timing and safety of ACEi/ARB prescription relative to hemodynamic stabilization (pre or post) in patients hospitalized with acute HFrEF/HFmrEF. This was a retrospective, observational analysis of electronic data of patients hospitalized for AHF at 17 Japanese hospitals. Among 9107 patients hospitalized with AHF, 2648 had HFrEF/HFmrEF, and 83.0% met the hemodynamic stabilization criteria within 10 days of admission. During hospitalization, 63.5% of patients with HFrEF/HFmrEF were prescribed an ACEi/ARB, 79.4% of which were prescribed pre-stabilization. In a multivariable analysis, patients treated with an ACEi/ARB pre-stabilization were more likely to have comorbid hypertension, diabetes mellitus, or ischemic heart disease. ACEi/ARB prescription timing was not associated with adverse events, including hypotension and renal impairment, and early prescription was associated with a lower incidence of subsequent worsening of HF. In clinical practice, more hospitalized patients with AHF received an ACEi/ARB before compared with after hemodynamic stabilization, and no safety concerns were observed. Moreover, early prescription may be associated with a lower incidence of worsening HF.

Long-Term Efficacy and Safety of Molidustat for Anemia in Chronic Kidney Disease: DIALOGUE Extension Studies.

BACKGROUND: Molidustat, a novel hypoxia-inducible factor-prolyl hydroxylase inhibitor, is being investigated for the treatment of anemia associated with chronic kidney disease (CKD). The efficacy and safety of molidustat were recently evaluated in three 16-week phase 2b studies. Here, we report the results of two long-term extension studies of molidustat. METHODS: Both studies were parallel-group, open-label, multicenter studies of ≤36 months' duration, in patients with anemia due to CKD, and included an erythropoiesis-stimulating agent as active control. One study enrolled patients not receiving dialysis (n = 164), and the other enrolled patients receiving hemodialysis (n = 88). The primary efficacy variable for both studies was change in blood hemoglobin (Hb) level from baseline to each post-baseline visit, and safety outcomes included adverse events (AEs). RESULTS: In patients not on dialysis, the mean ± SD Hb concentrations at baseline were 11.28 ± 0.55 g/dL for molidustat and 11.08 ± 0.51 g/dL for darbepoetin. The mean ± SD blood Hb concentrations throughout the study (defined as mean of each patient's overall study Hb levels) were 11.10 ± 0.508 and 10.98 ± 0.571 g/dL in patients treated with molidustat and darbepoetin, respectively. Similar proportions of patients reported at least one AE in the molidustat (85.6%) and darbepoetin (85.7%) groups. In patients on dialysis, mean ± SD Hb levels at baseline were 10.40 ± 0.70 and 10.52 ± 0.53 g/dL in the molidustat and epoetin groups, respectively. The mean ± SD blood Hb concentrations during the study were 10.37 ± 0.56 g/dL in the molidustat group and 10.52 ± 0.47 g/dL in the epoetin group. Proportions of patients who reported at least one AE were 91.2% in the molidustat group and 93.3% in the epoetin group. CONCLUSIONS: Molidustat was well tolerated for up to 36 months and appears to be an effective alternative to darbepoetin and epoetin in the long-term management of anemia associated with CKD.

MicroRNA-34a regulates cardiac ageing and function.

Ageing is the predominant risk factor for cardiovascular diseases and contributes to a significantly worse outcome in patients with acute myocardial infarction. MicroRNAs (miRNAs) have emerged as crucial regulators of cardiovascular function and some miRNAs have key roles in ageing. We propose that altered expression of miRNAs in the heart during ageing contributes to the age-dependent decline in cardiac function. Here we show that miR-34a is induced in the ageing heart and that in vivo silencing or genetic deletion of miR-34a reduces age-associated cardiomyocyte cell death. Moreover, miR-34a inhibition reduces cell death and fibrosis following acute myocardial infarction and improves recovery of myocardial function. Mechanistically, we identified PNUTS (also known as PPP1R10) as a novel direct miR-34a target, which reduces telomere shortening, DNA damage responses and cardiomyocyte apoptosis, and improves functional recovery after acute myocardial infarction. Together, these results identify age-induced expression of miR-34a and inhibition of its target PNUTS as a key mechanism that regulates cardiac contractile function during ageing and after acute myocardial infarction, by inducing DNA damage responses and telomere attrition.

Erratum to: 'Oral rivaroxaban for Japanese patients with symptomatic venous thromboembolism - the J-EINSTEIN DVT and PE program'.

[This corrects the article DOI: 10.1186/s12959-015-0035-3.].

Oral rivaroxaban for Japanese patients with symptomatic venous thromboembolism - the J-EINSTEIN DVT and PE program.

BACKGROUND: The global EINSTEIN DVT and PE studies compared rivaroxaban (15 mg twice daily for 3 weeks followed by 20 mg once daily) with enoxaparin/vitamin K antagonist therapy and demonstrated non-inferiority for efficacy and superiority for major bleeding. Owing to differences in targeted anticoagulant intensities in Japan, Japanese patients were not enrolled into the global studies. Instead, a separate study of deep vein thrombosis (DVT) and/or pulmonary embolism (PE) in Japanese patients was conducted, which compared the Japanese standard of care with a reduced dose of rivaroxaban. METHODS: We conducted an open-label, randomized trial that compared 3, 6, or 12 months of oral rivaroxaban alone (10 mg twice daily or 15 mg twice daily for 3 weeks followed by 15 mg once daily) with activated partial thromboplastin time-adjusted intravenous unfractionated heparin (UFH) followed by warfarin (target international normalized ratio 2.0; range 1.5-2.5) in patients with acute, objectively confirmed symptomatic DVT and/or PE. Patients were assessed for the occurrence of symptomatic recurrent venous thromboembolic events or asymptomatic deterioration and bleeding. RESULTS: Eighty-one patients were assigned to rivaroxaban and 19 patients to UFH/warfarin. Three patients were excluded because of serious non-compliance issues. The composite of symptomatic venous thromboembolic events or asymptomatic deterioration occurred in 1 (1.4%) rivaroxaban patient and in 1 (5.3%) UFH/warfarin patient (absolute risk difference, 3.9% [95% confidence interval, -3.4-23.8]). No major bleeding occurred during study treatment. Clinically relevant non-major bleeding occurred in 6 (7.8%) patients in the rivaroxaban group and 1 (5.3%) patient in the UFH/warfarin group. CONCLUSIONS: The findings of this study in Japanese patients with acute DVT and/or PE suggest a similar efficacy and safety profile with rivaroxaban and control treatment, consistent with that of the worldwide EINSTEIN DVT and PE program. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01516840 and NCT01516814.

Rivaroxaban vs. warfarin in Japanese patients with non-valvular atrial fibrillation in relation to age.

BACKGROUND: The J-ROCKET AF study found that rivaroxaban was non-inferior to warfarin with respect to the principal safety outcome in patients with atrial fibrillation (AF). The aim of this subgroup analysis was to assess the safety and efficacy of rivaroxaban and warfarin in relation to patient age. METHODS AND RESULTS: A total of 39.0% were elderly (aged ≥75 years). In elderly patients, the principal safety outcome occurred at 25.05%/year with rivaroxaban vs. 16.95%/year on warfarin (hazard ratio [HR], 1.49; 95% confidence interval [CI]: 1.02-2.16), whereas the primary efficacy endpoint occurred at 2.18%/year vs. 4.25%/year (HR, 0.51; 95% CI: 0.20-1.27), respectively. There were significant interactions in the principal safety outcomes of rivaroxaban compared with warfarin between the elderly and non-elderly groups, but not in the primary efficacy endpoints (P=0.04 and 0.82 for both interactions, respectively). Furthermore, in elderly patients, in the rivaroxaban group there was a trend to increase the principal safety outcome regardless of renal function. In elderly patients with preserved renal function, however, patients on rivaroxaban had a marginally favorable trend in the primary efficacy endpoint incidence rate compared with patients on warfarin. CONCLUSIONS: There is a need to carefully consider the risks and benefits of therapy with rivaroxaban in elderly patients with non-valvular AF.

Present profiles of novel anticoagulant use in Japanese patients with atrial fibrillation: insights from the Rivaroxaban Postmarketing Surveillance Registry.

BACKGROUND: The postmarketing surveillance registry evaluated the safety and efficacy of rivaroxaban in Japanese patients with atrial fibrillation (AF) treated with rivaroxaban. METHODS: A total of 10,038 patients with AF were enrolled between April 18, 2012 and December 16, 2013. Overall, 48.9% of the patients were of 75 years or older. The median CHADS2 score was 2 (interquartile range, 1-3). A total of 54.7% of patients had switched from an anticoagulant/antiplatelet drug, whereas 45.3% were treatment naive. Initial analysis was conducted for the 1039 patients who had completed the 6-month follow-up examinations by the end of June 2013. The low dose (10 mg/d) of rivaroxaban had been selected for approximately one quarter of the patients because of bleeding risks and advanced age in addition to renal impairment, although the high dose (15 mg/d) should have been selected. RESULTS: Major and nonmajor clinically relevant bleeding events were observed in 36 of 1035 patients. Five of 16 patients who concomitantly used 2 or more antiplatelet agents developed a bleeding event. Bleeding events were observed in 8 of 158 patients who were of 75 years or older and weighed 50 kg or less. The composite end point event of stroke, systemic embolism, or myocardial infarction was observed in 6 of 1034 patients. CONCLUSIONS: This registry will continue to provide insights into the safety and efficacy of rivaroxaban in real-world practice.

Rivaroxaban versus warfarin in Japanese patients with nonvalvular atrial fibrillation in relation to the CHADS2 score: a subgroup analysis of the J-ROCKET AF trial.

BACKGROUND: Results from a trial of rivaroxaban versus warfarin in 1280 Japanese patients with atrial fibrillation (J-ROCKET AF) revealed that rivaroxaban was noninferior to warfarin with respect to the principal safety outcome. In this subanalysis, we investigated the safety and efficacy of rivaroxaban and warfarin in relation to patients' CHADS2 scores. RESULTS: The mean CHADS2 score was 3.25, and the most frequent scores were 3 and 4. No statistically significant interactions were observed between principal safety outcome event rates and CHADS2 scores with respect to treatment groups (P value for interaction = .700). Irrespective of stratification into moderate- and high-risk groups based on CHADS2 scores of 2 and 3 or more, respectively, no differences in principal safety outcome event rates were observed between rivaroxaban- and warfarin-treated patients (moderate-risk group: hazard ratio [HR], 1.06; 95% confidence interval [CI], .58-1.95; high-risk group: HR, 1.11; 95% CI, .86-1.45; P value for interaction = .488). The primary efficacy end point rate in the rivaroxaban-treated group was numerically lower than in the warfarin-treated group, regardless of risk group stratification (moderate-risk group: HR, .46; 95% CI, .09-2.37; high-risk group: HR, .49; 95% CI, .22-1.11; P value for interaction = .935). CONCLUSION: This subanalysis indicated that the safety and efficacy of rivaroxaban compared with warfarin were similar, regardless of CHADS2 score.

Net clinical benefit of rivaroxaban versus warfarin in Japanese patients with nonvalvular atrial fibrillation: a subgroup analysis of J-ROCKET AF.

BACKGROUND: The risk factors that have been identified for bleeding events with rivaroxaban are predominantly the same as those predicting thromboembolic ones in patients with atrial fibrillation (AF). Our aim was to determine the net clinical benefit (NCB) from the results of the J-ROCKET AF trial, in which rivaroxaban was compared with warfarin in Japanese patients with AF. METHODS: Two strategies were adopted to quantify the NCB. First, the NCB was calculated as the number of ischemic strokes avoided with anticoagulation minus the number of excess intracranial hemorrhage (ICH) with a weight of 1.5. Second, the composite end point of major bleeding events and secondary efficacy end points (stroke, noncentral nervous system systemic embolism, myocardial infarction and death) to ascertain the NCB were established. Subgroup analysis by CHADS2 score or creatinine clearance was also performed. RESULTS: The adjusted NCB, which was given a weight of 1.5 for ICH, was nominally significant in favor of rivaroxaban therapy (difference in incidence rate -2.13; 95% confidence interval [CI]: -.26 to -3.99). Furthermore, the event rate of the composite end point tended to be lower in patients treated with rivaroxaban than in those treated with warfarin (rivaroxaban: 4.97% per year, warfarin: 6.11% per year; difference in incidence rate: -1.14; 95% CI: -3.40 to 1.12). The event rate of the composite end point tended to be consistently low in patients treated with rivaroxaban in the subanalysis by CHADS2 score and renal function. CONCLUSION: Analysis of the NCB supports that rivaroxaban therapy provides clinical benefit for Japanese patients with AF.

Regulation of cardiac microRNAs by bone marrow mononuclear cell therapy in myocardial infarction.

BACKGROUND: Cell therapy with bone marrow-derived mononuclear cells (BMCs) can improve recovery of cardiac function after ischemia; however, the molecular mechanisms are not yet fully understood. MicroRNAs (miRNAs) are key regulators of gene expression and modulate the pathophysiology of cardiovascular diseases. METHODS AND RESULTS: We demonstrated that intramyocardial delivery of BMCs in infarcted mice regulates the expression of cardiac miRNAs and significantly downregulates the proapoptotic miR-34a. In vitro studies confirmed that the supernatant of BMC inhibited the expression of H(2)O(2)-induced miR-34a and cardiomyocytes apoptosis. These effects were blocked by neutralizing antibodies directed against insulin-like growth factor-1 (IGF-1). Indeed, IGF-1 significantly inhibited H(2)O(2)-induced miR-34a expression, and miR-34a overexpression abolished the antiapoptotic effect of IGF-1. Likewise, inhibition of IGF-1 signaling in vivo abolished the BMC-mediated inhibition of miR-34 expression and the protective effect on cardiac function and increased apoptosis and cardiac fibrosis. IGF-1 specifically blocked the expression of the precursor and the mature miR-34a, but did not interfere with the transcription of the primary miR-34a demonstrating that IGF-1 blocks the processing of miR-34a. CONCLUSIONS: Together, our data demonstrate that the paracrine regulation of cardiac miRNAs by transplanted BMCs contributes to the protective effects of cell therapy. BMCs release IGF-1, which inhibits the processing of miR-34a, thereby blocking cardiomyocyte apoptosis.

Hepatocyte growth factor inhibits lipopolysaccharide-induced oxidative stress via epithelial growth factor receptor degradation.

OBJECTIVE: Lipopolysaccharide (LPS) triggers sepsis and systemic inflammatory response syndrome, which results in multiple organ failure. Our recent reports demonstrated that hepatocyte growth factor (HGF) attenuated angiotensin II-induced oxidative stress via epithelial growth factor receptor (EGFR) degradation in vascular smooth muscle cells. Here, we examined whether HGF can protect against systemic inflammatory response syndrome induced by LPS and investigated the mechanism. METHODS AND RESULTS: HGF inhibited the increase in the expression of vascular cell adhesion molecule-1 and EGFR by LPS in vitro. HGF inhibited colocalization of EGFR and Src homology domain 2-containing inositol 5'-phosphatase 2. Furthermore, HGF inhibited reactive oxygen species production. We also injected LPS into HGF transgenic mice with increased HGF serum concentration and their littermates. HGF transgenic mice reduced LPS-induced vascular cell adhesion molecule-1 and reactive oxygen species compared with control, accompanied by significant EGFR degradation. Furthermore, HGF transgenic mice significantly improved survival in the LPS injection model. CONCLUSIONS: The present study revealed inhibition of LPS-induced vascular cell adhesion molecule-1 expression by HGF via the degradation of EGFR. We demonstrated that HGF regulated Src homology domain 2-containing inositol 5'-phosphatase 2 recruitment to EGFR and inhibited LPS-induced inflammation via EGFR degradation. This effect of HGF may be useful for the treatment of inflammatory disease.

Acute myocardial infarction activates progenitor cells and increases Wnt signalling in the bone marrow.

AIMS: We aimed to characterize the influence of acute myocardial infarction (AMI) on the metabolic activity of the bone marrow (BM) and on the composition and functional activity of BM-derived mononuclear cells (BMC). Acute ischaemia or other stressors induce the mobilization of progenitor cells from the BM stem cell niche. The effect of AMI on the numbers and functional activity of cells within the BM is unknown. METHODS AND RESULTS: In patients of the REPAIR-AMI trial as well as in mice, the number and functionality of BMC was compared with respect to the time interval from AMI. Activation of Wnt signalling was assessed after AMI induction in TOP-GAL transgenic reporter mice, carrying a ß-galactosidase gene driven by an LEF/TCF/ß-catenin responsive promoter. The metabolic activity of the BM, as determined by F-18-fluorodeoxyglucose-positron emission tomography, was significantly higher in patients with AMI compared with patients with chronic post-ischaemic heart failure. Moreover, the number of haematopoietic CD34(+) (P < 0.05) and CD133(+) (P < 0.05) cells in the BM aspirates was significantly increased in patients within 7 days after AMI. In order to confirm these clinical data, we induced AMI in mice, which time-dependently increased the number of c-kit + Sca-1 + lin- cells and colony-forming units in the BM. Activation of the BM by AMI induced a significant increase in Wnt signalling, which is known to induce proliferation of haematopoietic stem cells, and demonstrated increased levels of the Wnt target Axin-2 in BM-derived cells on Day 7 (P < 0.01 vs. control). CONCLUSION: Acute myocardial infarction is associated with an increased metabolic activity and increased levels of progenitor cells within days after AMI. These findings document an activation of the stem cell niche within the BM following AMI, which may have important implications for the optimal timing of cell aspirations used for therapeutic application in patients with AMI.

Twenty-Four-Hour Blood Pressure-Lowering Efficacy of Sacubitril/Valsartan Versus Olmesartan in Japanese Patients With Essential Hypertension Based on Nocturnal Blood Pressure Dipping Status: A Post Hoc Analysis of Data From a Randomized, Double-Blind Multicenter Study.

Background Nighttime blood pressure (BP) and an abnormal nocturnal BP dipping profile are important cardiovascular risk factors in patients with hypertension. This post hoc analysis investigated the effects of sacubitril/valsartan on 24-hour BP in patients with mild-to-moderate hypertension and in patient subgroups based on nocturnal BP dipping status. Methods and Results Data from a randomized clinical trial comparing the BP-lowering effects of 8 weeks of treatment with sacubitril/valsartan (200 or 400 mg/d) and olmesartan (20 mg/d) in Japanese patients with mild-to-moderate hypertension were analyzed. The primary end point was change in 24-hour, daytime, and nighttime BP in patient subgroups based on nocturnal BP dipping status (dipper, nondipper). Six hundred thirty-two patients with baseline and follow-up ambulatory BP data were included. Both sacubitril/valsartan dosages reduced 24-hour, daytime, and nighttime systolic BP, and 24-hour and daytime diastolic BP, to a significantly greater extent than olmesartan in the dipper and nondipper groups. However, between-group differences in nighttime systolic BP were more significant in the nondipper group (difference [95% CI] for sacubitril/valsartan 200 and 400 mg/d versus olmesartan 20 mg/d: -4.6 [95% CI, -7.3 to -1.8] and -6.8 [95% CI, -9.5 to -4.1] mm Hg, respectively; P<0.01 and P<0.001). Between-group differences in the BP control rate were greatest in the nondipper subgroup (systolic BP control rate of 34.4% and 42.6% with sacubitril/valsartan 200 and 400 mg/d versus 23.1% with olmesartan 20 mg/d). Conclusions This analysis highlights the value of sacubitril/valsartan therapy in patients with a nondipper profile of nocturnal BP and confirms this agent's potent 24-hour BP-lowering effect in Japanese populations with hypertension. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01599104.

Relationship Between Left Ventricular Ejection Fraction and Treatment Characteristics in Hospitalized Patients With Heart Failure　- A Japanese Database Analysis.

Background: Triple combination therapy with a renin-angiotensin system modulator, a ß-blocker, and a mineralocorticoid receptor antagonist is currently recommended for patients with heart failure (HF) with reduced ejection fraction. However, there is limited evidence on the extent to which triple combination therapy is currently prescribed to patients at the time of discharge from hospital in Japan. Methods and Results: Japanese patients hospitalized for HF (n=3,582) were evaluated in subgroups defined by left ventricular ejection fraction (LVEF) using anonymized claims and electronic health record data. At discharge, triple combination therapy prescription rates were low (40.4%, 30.0%, 20.8%, 14.0%, and 12.5% for patients with LVEF <30%, 30-<40%, 40-<50%, 50-<60%, and ≥60%, respectively). Advanced age, lower levels of B-type natriuretic peptide, and renal impairment were all significantly associated with lower rates of triple combination therapy use in the overall population. There were no significant differences in rehospitalization rates between LVEF subgroups; however, triple combination therapy use was associated with a significantly reduced risk of rehospitalization for HF in patients with LVEF <30%, 30-<40%, and 40-<50%. Conclusions: The use of triple combination therapy was significantly associated with a lower risk of rehospitalization for HF within 1 year of discharge in patients with LVEF <30%, 30-<40%, and 40-<50%. However, patients were undertreated with triple combination therapy.

Achievement Rates for Low-Density Lipoprotein Cholesterol Goals in Patients at High Risk of Atherosclerotic Cardiovascular Disease in a Real-World Setting in Japan.

AIMS: The study aimed to investigate low-density lipoprotein cholesterol (LDL-C) goal achievement rates in patients receiving LDL-C-lowering therapy using recent real-world data, following the 2017 revision of the Japan Atherosclerosis Society Guidelines for Prevention of Atherosclerotic Cardiovascular Diseases (JAS GL2017). METHODS: Patients with documented LDL-C test results were extracted from the Medical Data Vision claims database between July 2018 and June 2021 and divided into three groups according to JAS GL2017: primary prevention high risk (Group I, LDL-C goal ＜120 mg/dL), secondary prevention (Group II, LDL-C goal ＜100 mg/dL), and secondary prevention high risk (Group III, LDL-C goal ＜70 mg/dL). RESULTS: The mean LDL-C value was 108.7 mg/dL (n=125,235), 94.4 mg/dL (n=57,910), and 90.6 mg/dL (n=33,850) in Groups I, II, and III, respectively. Intensive statin monotherapy (pitavastatin, rosuvastatin, or atorvastatin) was the most frequently prescribed lipid-lowering treatment (21.6%, 30.8%, and 42.7% in Groups I, II, and III, respectively), followed by ezetimibe (2.5%, 7.1%, and 8.5% in Groups I, II, and III, respectively). LDL-C goals were achieved by 65.5%, 60.6%, and 25.4% of patients overall in Groups I, II, and III, respectively. Achievement rates were 83.9%, 75.3%, and 29.5% in patients prescribed intensive statin monotherapy and 82.3%, 86.4%, and 46.4% in those prescribed statin and ezetimibe combinations in Groups I, II, and III, respectively. In Group III, the proportion of patients with familial hypercholesterolemia prescribed statin and ezetimibe combinations achieving LDL-C goals was low (32.5%). CONCLUSIONS: The proportion of patients achieving LDL-C goals for secondary prevention in the high-risk group remains low even with statin and ezetimibe combination therapy.

Inhibition of Lp(a)-induced functional impairment of endothelial cells and endothelial progenitor cells by hepatocyte growth factor.

BACKGROUND: Lipoprotein (a) (Lp(a)) is one of the risk factors for peripheral artery disease (PAD). Our previous report demonstrated that hepatocyte growth factor (HGF) gene therapy attenuated the impairment of collateral formation in Lp(a) transgenic mice. Since risk factors for atherosclerosis accelerate endothelial senescence and impair angiogenesis, we examined the role of Lp(a) in dysfunction and senescence of endothelial progenitor cells (EPC) and endothelial cells. METHODS: In vitro and in vivo incorporation assays were performed using ex-vivo expanded DiI-labeled human EPC. Senescence of cultured endothelial cells, production of oxidative stress and angiogenesis function were evaluated by SA-ß-galactosidase staining, dihydroethidium (DHE) staining and Matrigel assay, respectively. RESULTS: EPC transplantation significantly stimulated recovery of ischemic limb perfusion, while EPC pre-treated with Lp(a) did not increase ischemic limb perfusion. Impairment of angiogenesis by EPC with Lp(a) was associated with a significant decrease in CD31-positive capillaries and DiI-labeled EPC. Importantly, Lp(a) significantly accelerated the onset of senescence and production of reactive oxygen species (ROS) in human aortic endothelial cells, accompanied by a significant increase in the protein expression of p53 and p21. On the other hand, HGF significantly attenuated EPC dysfunction, senescence, ROS production, and p53 and p21 expression induced by Lp(a). CONCLUSION: Lp(a) might affect atherosclerosis via acceleration of senescence, ROS production, and functional impairment of the endothelial cell lineage. HGF might have inhibitory effects on these atherogenic actions of Lp(a).

Sox2 transduction enhances cardiovascular repair capacity of blood-derived mesoangioblasts.

RATIONALE: Complementation of pluripotency genes may improve adult stem cell functions. OBJECTIVES: Here we show that clonally expandable, telomerase expressing progenitor cells can be isolated from peripheral blood of children. The surface marker profile of the clonally expanded cells is distinct from hematopoietic or mesenchymal stromal cells, and resembles that of embryonic multipotent mesoangioblasts. Cell numbers and proliferative capacity correlated with donor age. Isolated circulating mesoangioblasts (cMABs) express the pluripotency markers Klf4, c-Myc, as well as low levels of Oct3/4, but lack Sox2. Therefore, we tested whether overexpression of Sox2 enhances pluripotency and facilitates differentiation of cMABs in cardiovascular lineages. METHODS AND RESULTS: Lentiviral transduction of Sox2 (Sox-MABs) enhanced the capacity of cMABs to differentiate into endothelial cells and cardiomyocytes in vitro. Furthermore, the number of smooth muscle actin positive cells was higher in Sox-MABs. In addition, pluripotency of Sox-MABs was shown by demonstrating the generation of endodermal and ectodermal progenies. To test whether Sox-MABs may exhibit improved therapeutic potential, we injected Sox-MABs into nude mice after acute myocardial infarction. Four weeks after cell therapy with Sox-MABs, cardiac function was significantly improved compared to mice treated with control cMABs. Furthermore, cell therapy with Sox-MABs resulted in increased number of differentiated cardiomyocytes, endothelial cells, and smooth muscle cells in vivo. CONCLUSIONS: The complementation of Sox2 in Oct3/4-, Klf4-, and c-Myc-expressing cMABs enhanced the differentiation into all 3 cardiovascular lineages and improved the functional recovery after acute myocardial infarction.

Mechanism of improved cardiac function after bone marrow mononuclear cell therapy: role of cardiovascular lineage commitment.

BACKGROUND: Cell therapy is a promising option to improve functional recovery after ischemia. Several subsets of bone marrow-derived cells were shown to reduce infarct size and increase ejection fraction in experimental models of ischemia. The mechanisms underlying the functional improvement are diverse and have been shown to include paracrine effects of the injected cells, as well as a variable degree of differentiation to endothelial cells, pericytes, smooth muscle, and cardiac muscle. METHODS AND RESULTS: To elucidate the true nature of such plasticity and contribution to recovery, we engineered vectors that encoded inducible suicide genes under the control of endothelium (endothelial nitric oxide synthase)-, smooth muscle (SM22alpha)-, and cardiomyocyte (alpha-MHC)-specific promoters, thereby allowing selective depletion of the individual cell lineage acquired by the transplanted undifferentiated bone marrow-derived cells. Lentivirally delivered thymidine kinase, which converts the prodrug ganciclovir into a cytotoxic agent, was used to selectively eliminate cells 2 weeks after transplantation of bone marrow mononuclear cells in an acute myocardial infarction model. We demonstrate that elimination of transplanted endothelium-committed or SM22alpha-expressing cells, but not cardiac-committed cells, induced a significant deterioration of ejection fraction. Moreover, elimination of endothelial nitric oxide synthase-expressing cells 2 weeks after injection reduced capillary and arteriole density. CONCLUSIONS: This study demonstrates that elimination of bone marrow mononuclear cells reexpressing endothelial nitric oxide synthase particularly induced a deterioration of cardiac function, which indicates a functional contribution of the vascular cell fate decision of human bone marrow-derived mononuclear cells in vivo.

Negative action of hepatocyte growth factor/c-Met system on angiotensin II signaling via ligand-dependent epithelial growth factor receptor degradation mechanism in vascular smooth muscle cells.

RATIONALE: Neointimal hyperplasia contributes to atherosclerosis and restenosis after percutaneous coronary intervention. Vascular injury in each of these conditions results in the release of mitogenic growth factors and hormones that contribute to pathological vascular smooth muscle cell growth and inflammation. Hepatocyte growth factor (HGF) is known as an antiinflammatory growth factor, although it is downregulated in injured tissue. However, the precise mechanism how HGF reduces inflammation is unclear. OBJECTIVE: To elucidate the mechanism how HGF and its receptor c-Met reduces angiotensin II (Ang II)-induced inflammation. METHODS AND RESULTS: HGF reduced Ang II-induced vascular smooth muscle cell growth and inflammation by controlling translocation of SHIP2 (Src homology domain 2-containing inositol 5'-phosphatase 2), which led to Ang II-dependent degradation of epithelial growth factor receptor. Moreover, the present study also revealed a preventive effect of HGF on atherosclerotic change in an Ang II infusion and cuff HGF transgenic mouse model. CONCLUSIONS: These data suggest that the HGF/c-Met system might regulate extrinsic factor signaling that maintains the homeostasis of organs.

Preconditioning by toll-like receptor 2 agonist Pam3CSK4 reduces CXCL1-dependent leukocyte recruitment in murine myocardial ischemia/reperfusion injury.

OBJECTIVE: To test whether preconditioning with a toll-like receptor (TLR) 2 agonist protects against myocardial ischemia and reperfusion by interfering with chemokine CXCL1 release from cardiomyocytes. DESIGN: C3H mice were challenged with vehicle or synthetic TLR2 agonist Pam3Cys-Ser-Lys4 (Pam3CSK4; 1 mg/kg) 24 hrs before myocardial ischemia (20 mins) and reperfusion (2 hrs or 24 hrs). Infarct size, troponin T release, and leukocyte recruitment were quantified. In murine cardiomyocytes (HL-1), we studied the expression/activation profile of TLR2 in response to stimulation with Pam3CSK4 (0.01-1 mg/mL). Furthermore, we studied the chemokine ligand 1 (CXCL1) response to Pam3CSK4 and ischemia/reperfusion in vivo and in vitro. SETTING: University hospital research laboratory. SUBJECTS: Anesthetized male mice and murine cardiomyocytes. MEASUREMENTS AND MAIN RESULTS: Preconditioning by Pam3CSK4 reduced infarct size and troponin T release. This was accompanied by a decreased recruitment of leukocytes into the ischemic area and an improved cardiac function. In HL-1 cells, TLR2 activation amplified the expression of the receptor in a time-dependent manner and led to CXCL1 release in a concentration-dependent manner. Preconditioning by Pam3CSK4 impaired CXCL1 release in response to a second inflammatory stimulus in vivo and in vitro. CONCLUSIONS: Preconditioning by TLR2 agonist Pam3CSK4 reduces myocardial infarct size after myocardial ischemia/reperfusion. One of the mechanisms involved is a diminished chemokine release from cardiomyocytes, which subsequently limits leukocyte infiltration.