A randomized controlled study of finerenone versus placebo in Japanese patients with type 2 diabetes mellitus and diabetic nephropathy.

AIMS: Finerenone (BAY 94-8862) is a novel non-steroidal mineralocorticoid receptor antagonist. The aim of this study was to compare the efficacy and safety of seven once-daily oral doses of finerenone (1.25-20mg) and placebo in 96 patients with type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) receiving a RAS blocker. METHODS: ARTS-DN Japan was a multicenter, randomized, double-blind, placebo-controlled, phase 2b study. RESULTS: Analysis of the urinary albumin-to-creatinine ratio (UACR) at day 90 relative to baseline indicated a nominally significant effect of finerenone. The UACR at day 90 relative to baseline for each finerenone treatment group was numerically reduced compared with placebo. No serious adverse events (AEs) or deaths were reported and no patients experienced treatment-emergent AEs resulting in discontinuation of study drug. Small mean increases in serum potassium level were observed in the finerenone treatment groups (0.025-0.167mmol/L) compared with the placebo group (-0.075mmol/L); no patients developed hyperkalemia. CONCLUSION: When given in addition to a RAS inhibitor, finerenone reduced albuminuria without adverse effects on serum potassium levels or renal function in Japanese patients with T2DM and DN.

A Randomized Controlled Study of Finerenone vs. Eplerenone in Japanese Patients With Worsening Chronic Heart Failure and Diabetes and/or Chronic Kidney Disease.

BACKGROUND: Finerenone, a nonsteroidal mineralocorticoid receptor antagonist, was evaluated in Japanese patients with heart failure (HF) with reduced ejection fraction and chronic kidney disease and/or diabetes mellitus. METHODS AND RESULTS: ARTS-HF Japan was a randomized, double-blind, phase 2b study. Patients (n=72) received oral, once-daily (o.d.) finerenone (2.5, 5, 7.5, 10 or 15 mg, up-titrated to 5, 10, 15, 20, or 20 mg, respectively, on day 30) or eplerenone (25 mg every other day, increased to 25 mg o.d. on day 30, and 50 mg on day 60) for 90 days. The primary endpoint was the proportion of individuals with a decrease of >30% in plasma NT-proBNP at day 90. Safety endpoints included the incidence of hyperkalemia. Decreases in NT-proBNP occurred in 23.1% of patients in the eplerenone group and 15.4%, 23.1%, 45.5%, 27.3% and 45.5% in the 2.5→5 mg, 5→10 mg, 7.5→15 mg, 10→20 mg and 15→20 mg finerenone groups, respectively (all P=NS). Mean changes in serum potassium levels were similar between groups. CONCLUSIONS: Because of the small sample size, limited conclusions can be drawn. Considering the results of ARTS-HF and that finerenone was well tolerated in Japanese patients in ARTS-HF Japan, the safety and efficacy of finerenone should be further explored in a large outcomes trial including Japanese patients. (Circ J 2016; 80: 1113-1122).

Efficacy and Safety of Inhaled Iloprost in Japanese Patients With Pulmonary Arterial Hypertension　- Insights From the IBUKI and AIR Studies.

BACKGROUND: Inhaled iloprost is approved for pulmonary arterial hypertension (PAH) in many countries. IBUKI was a phase III, non-randomized, open-label study of the efficacy and safety of inhaled iloprost in Japanese patients with PAH. METHODS AND RESULTS: Adults with PAH who were treatment-naïve or administered endothelin receptor antagonists (ERAs) and/or phosphodiesterase type 5 inhibitors (PDE5-Is) and in NYHA/WHO functional class (FC) III/IV had inhaled iloprost (2.5 µg, increased to 5.0 µg if tolerated) 6-9 times daily for 12 weeks. Eligible patients entered a 40-week extension phase. Endpoints included change from baseline to week 12 in pulmonary vascular resistance (PVR; primary endpoint), other efficacy parameters, and safety. Data were compared with new subgroup analyses of treatment-naïve Western PAH patients from the global phase III AIR study. 27 patients received iloprost: 89% were treated with an ERA and/or PDE5-I; 70% with both. At week 12, PVR improved from baseline by -124 dyn·sec·cm(-5)(95% CI, -177 to -72) and 6-min walking distance increased by 36.0 m (95% CI, 14.9 to 57.1). NYHA/WHO FC improved in 62%; none worsened. Common drug-related adverse events were headache (37%) and cough (15%); 1 patient experienced hypotension; none reported syncope or hemoptysis. There were no deaths and no unexpected long-term safety findings. AIR PAH subgroup analyses showed similar results. CONCLUSIONS: Inhaled iloprost appeared effective and safe in Japanese PAH patients, including ERA- and PDE5-I-treated patients, consistent with findings of the AIR PAH subpopulation and previous iloprost studies.

Direct binding and regulation of RhoA protein by cyclic GMP-dependent protein kinase Iα.

Vascular smooth muscle cell (VSMC) tone is regulated by the state of myosin light chain (MLC) phosphorylation, which is in turn regulated by the balance between MLC kinase and MLC phosphatase (MLCP) activities. RhoA activates Rho kinase, which phosphorylates the regulatory subunit of MLC phosphatase, thereby inhibiting MLC phosphatase activity and increasing contraction and vascular tone. Nitric oxide is an important mediator of VSMC relaxation and vasodilation, which acts by increasing cyclic GMP (cGMP) levels in VSMC, thereby activating cGMP-dependent protein kinase Iα (PKGIα). PKGI is known to phosphorylate Rho kinase, preventing Rho-mediated inhibition of MLC phosphatase, promoting vasorelaxation, although the molecular mechanisms that mediate this are unclear. Here we identify RhoA as a target of activated PKGIα and show further that PKGIα binds directly to RhoA, inhibiting its activation and translocation. In protein pulldown and immunoprecipitation experiments, binding of RhoA and PKGIα was demonstrated via a direct interaction between the amino terminus of RhoA (residues 1-44), containing the switch I domain of RhoA, and the amino terminus of PKGIα (residues 1-59), which includes a leucine zipper heptad repeat motif. Affinity assays using cGMP-immobilized agarose showed that only activated PKGIα binds RhoA, and a leucine zipper mutant PKGIα was unable to bind RhoA even if activated. Furthermore, a catalytically inactive mutant of PKGIα bound RhoA but did not prevent RhoA activation and translocation. Collectively, these results support that RhoA is a PKGIα target and that direct binding of activated PKGIα to RhoA is central to cGMP-mediated inhibition of the VSMC Rho kinase contractile pathway.

Human atrial natriuretic peptide and nicorandil as adjuncts to reperfusion treatment for acute myocardial infarction (J-WIND): two randomised trials.

BACKGROUND: Patients who have acute myocardial infarction remain at major risk of cardiovascular events. We aimed to assess the effects of either human atrial natriuretic peptide or nicorandil on infarct size and cardiovascular outcome. METHODS: We enrolled 1216 patients who had acute myocardial infarction and were undergoing reperfusion treatment in two prospective, single-blind trials at 65 hospitals in Japan. We randomly assigned 277 patients to receive intravenous atrial natriuretic peptide (0.025 microg/kg per min for 3 days) and 292 the same dose of placebo. 276 patients were assigned to receive intravenous nicorandil (0.067 mg/kg as a bolus, followed by 1.67 microg/kg per min as a 24-h continuous infusion), and 269 the same dose of placebo. Median follow-up was 2.7 (IQR 1.5-3.6) years for patients in the atrial natriuretic peptide trial and 2.5 (1.5-3.7) years for those in the nicorandil trial. Primary endpoints were infarct size (estimated from creatine kinase) and left ventricular ejection fraction (gauged by angiography of the left ventricle). FINDINGS: 43 patients withdrew consent after randomisation, and 59 did not have acute myocardial infarction. We did not assess infarct size in 50 patients for whom we had fewer than six samples of blood. We did not have angiographs of left ventricles in 383 patients. Total creatine kinase was 66,459.9 IU/mL per h in patients given atrial natriuretic peptide, compared with 77,878.9 IU/mL per h in controls, with a ratio of 0.85 between these groups (95% CI 0.75-0.97, p=0.016), which indicated a reduction of 14.7% in infarct size (95% CI 3.0-24.9%). The left ventricular ejection fraction at 6-12 months increased in the atrial natriuretic peptide group (ratio 1.05, 95% CI 1.01-1.10, p=0.024). Total activity of creatine kinase did not differ between patients given nicorandil (70 520.5 IU/mL per h) and controls (70 852.7 IU/mL per h) (ratio 0.995, 95% CI 0.878-1.138, p=0.94). Intravenous nicorandil did not affect the size of the left ventricular ejection fraction, although oral administration of nicorandil during follow-up increased the left ventricular ejection fraction between the chronic and acute phases. 29 patients in the atrial natriuretic peptide group had severe hypotension, compared with one in the corresponding placebo group. INTERPRETATION: Patients with acute myocardial infarction who were given atrial natriuretic peptide had lower infarct size, fewer reperfusion injuries, and better outcomes than controls. We believe that atrial natriuretic peptide could be a safe and effective adjunctive treatment in patients with acute myocardial infarction who receive percutaneous coronary intervention.

Increased endoplasmic reticulum stress in atherosclerotic plaques associated with acute coronary syndrome.

BACKGROUND: The endoplasmic reticulum (ER) responds to various stresses by upregulation of ER chaperones, but prolonged ER stress eventually causes apoptosis. Although apoptosis is considered to be essential for the progression and rupture of atherosclerotic plaques, the influence of ER stress and apoptosis on rupture of unstable coronary plaques remains unclear. METHODS AND RESULTS: Coronary artery segments were obtained at autopsy from 71 patients, and atherectomy specimens were obtained from 40 patients. Smooth muscle cells and macrophages in the fibrous caps of thin-cap atheroma and ruptured plaques, but not in the fibrous caps of thick-cap atheroma and fibrous plaques, showed a marked increase of ER chaperone expression and apoptotic cells. ER chaperones also showed higher expression in atherectomy specimens from patients with unstable angina pectoris than in specimens from those with stable angina. Expression of 7-ketocholesterol was increased in the fibrous caps of thin-cap atheroma compared with thick-cap atheroma. Treatment of cultured coronary artery smooth muscle cells or THP-1 cells with 7-ketocholesterol induced upregulation of ER chaperones and apoptosis, whereas these changes were prevented by antioxidants. We also investigated possible signaling pathways for ER-initiated apoptosis and found that the CHOP (a transcription factor induced by ER stress)-dependent pathway was activated in unstable plaques. In addition, knockdown of CHOP expression by small interfering RNA decreased ER stress-dependent death of cultured coronary artery smooth muscle cells and THP-1 cells. CONCLUSIONS: Increased ER stress occurs in unstable plaques. Our findings suggest that ER stress-induced apoptosis of smooth muscle cells and macrophages may contribute to plaque vulnerability.

Erythropoietin enhances neovascularization of ischemic myocardium and improves left ventricular dysfunction after myocardial infarction in dogs.

OBJECTIVES: We investigated the effects of erythropoietin (EPO) on neovascularization and cardiac function after myocardial infarction (MI). BACKGROUND: Erythropoietin exerts antiapoptotic effects and mobilizes endothelial progenitor cells (EPCs). METHODS: We intravenously administered EPO (1,000 IU/kg) immediately [EPO(0) group], 6 h [EPO(6h) group], or 1 week [EPO(1wk) group] after the permanent ligation of the coronary artery in dogs. Control animals received saline immediately after the ligation. RESULTS: The infarct size 6 h after MI was significantly smaller in the EPO(0) group than in the control group (61.5 +/- 6.0% vs. 22.9 +/- 2.2%). One week after MI, the circulating CD34-positive mononuclear cell numbers in both the EPO(0) and the EPO(6h) groups were significantly higher than in the control group. In the ischemic region, the capillary density and myocardial blood flow 4 weeks after MI was significantly higher in both the EPO(0) and the EPO(6h) groups than in the control group. Four weeks after MI, left ventricular (LV) ejection fraction in the EPO(6h) (48.6 +/- 1.9%) group was significantly higher than that in either the control (41.9 +/- 0.9%) or the EPO(1wk) (42.6 +/- 1.2%) group but significantly lower than that in the EPO(0) group (56.1 +/- 2.3%). The LV end-diastolic pressure 4 weeks after MI in both the EPO(0) and the EPO(6h) groups was significantly lower than either the control or the EPO(1wk) group. Hematologic parameters did not differ among the groups. CONCLUSIONS: In addition to its acute infarct size-limiting effect, EPO enhances neovascularization, likely via EPC mobilization, and improves cardiac dysfunction in the chronic phase, although it has time-window limitations.

Angiotensin II type 1 receptor blocker prevents atrial structural remodeling in rats with hypertension induced by chronic nitric oxide inhibition.

The prevalence of atrial fibrillation (AF) increases in patients with hypertension. Angiotensin II is involved in structural atrial remodeling, which contributes to the onset and maintenance of AF in paced animal models. We investigated the role of angiotensin II in atrial structural remodeling in rats with hypertension. Ten-week-old male Wistar-Kyoto rats were randomly divided into 4 groups: a control group (no treatment), an Nomega-nitro-L-arginine methyl ester (L-NAME) group (administered L-NAME, an inhibitor of nitric oxide synthase, 1 g/l in drinking water), an L-NAME+candesartan group (L-NAME plus candesartan-an angiotensin II receptor blocker (ARB)-at 0.1 mg/kg/day), and an L-NAME + hydralazine group (L-NAME plus hydralazine at 120 mg/l in drinking water). Eight weeks after treatment, the L-NAME group showed significantly higher systolic blood pressure than the control group (197 +/- 12 vs.138 +/- 5 mmHg, p < 0.05). Candesartan or hydralazine with L-NAME reduced systolic blood pressure to baseline. Chronic inhibition of NO synthesis increased the extent of fibrosis and transforming growth factor-beta expression in atrial tissue, and both of these effects were prevented by candesartan, but not by hydralazine. Cardiac hypertrophy and dysfunction were induced in the L-NAME group, and these effects were also prevented by candesartan, but not by hydralazine. In contrast, the decrease in thrombomodulin expression in the atrial endocardium in hypertensive rats was restored by candesartan and hydralazine. The ARB prevented atrial structural remodeling, a possible contributing factor for the development of AF, in the hearts of rats with hypertension induced by long-term inhibition of NO synthesis.

Blockade of histamine H2 receptors protects the heart against ischemia and reperfusion injury in dogs.

We have previously reported that histamine H(2) blockers may be cardioprotective in patients with chronic heart failure. Since both endogenous histamine and histamine H(2) receptors are present in heart tissue, we tested the hypothesis that the blockade of histamine H(2) receptors mediates protection against reversible or irreversible ischemia and reperfusion injury. In open-chest dogs, the left anterior descending coronary artery was occluded for 90 minutes, followed by reperfusion for 6 hours. Administration of famotidine and cimetidine from 10 minutes before occlusion until after 1 hour of reperfusion reduced infarct size (17.0 +/- 4.1% and 17.8 +/- 2.9% vs. 36.9 +/- 5.9% of the solvent group, respectively) Famotidine administration only during the reperfusion period for 1 hour also attenuated infarct size (22.5 +/- 3.5%). There were no differences in either area at risk or collateral flow among the groups. In another set of experiments, we decreased coronary perfusion pressure in dogs so that the coronary blood flow decreased to 50% of the non-ischemic level. In such conditions, we observed the increases in histamine release compared with non-ischemic conditions (0.04 +/- 0.03 to 0.28 +/- 0.13 ng/ml, p < 0.05). Famotidine improved anaerobic myocardial metabolism gauged by both lactate extraction ratio and myocardial oxygen consumption. We conclude that the blockade of histamine H(2) receptors mediates improvements in the anaerobic myocardial metabolism, and thus protects against ischemia and reperfusion injury.

Aldosterone nongenomically worsens ischemia via protein kinase C-dependent pathways in hypoperfused canine hearts.

Rapid nongenomic actions of aldosterone independent of mineralocorticoid receptors (MRs) on vascular tone are divergent. Until now, the rapid nongenomic actions of aldosterone on vascular tone of coronary artery and cardiac function in the in vivo ischemic hearts were not still fully estimated. Furthermore, although aldosterone can modulate protein kinase C (PKC) activity, there is no clear consensus whether PKC is involved in the nongenomic actions of aldosterone on the ischemic hearts. In open chest dogs, the selective infusion of aldosterone into the left anterior descending coronary artery (LAD) reduced coronary blood flow (CBF) in the nonischemic hearts in a dose-dependent manner. Also, in the ischemic state that CBF was decreased to 33% of the baseline, the intracoronary administration of aldosterone (0.1 nmol/L) rapidly decreased CBF (37.4+/-3.8 to 19.3+/-5.2 mL/100 g/min; P<0.05), along with decreases in fractional shortening (FS) (8.4+/-0.7 to 5.4+/-0.4%; P<0.05) and lactate extraction rate (LER) (-31.7+/-2.9 to -41.4+/-3.7%; P<0.05). The decrease in CBF was reproduced by the infusion of bovine serum albumin-conjugated aldosterone. Notably, these aldosterone-induced deteriorations of myocardial contractile and metabolic functions were blunted by the co-administration of GF109203X, an inhibitor of PKC, but not spironolactone. In addition, aldosterone activated vascular PKC. These results indicate that aldosterone nongenomically induces vasoconstriction via PKC-dependent pathways possibly through membrane receptors, which leads to the worsening of the cardiac contractile and metabolic functions in the ischemic hearts. Elevation of plasma or cardiac aldosterone levels may be deleterious to ischemic heart disease through its nongenomic effects.

Erythropoietin just before reperfusion reduces both lethal arrhythmias and infarct size via the phosphatidylinositol-3 kinase-dependent pathway in canine hearts.

Although recent studies suggest that erythropoietin (EPO) may reduce multiple features of the myocardial ischemia/reperfusion injury, the cellular mechanisms and the clinical implications of EPO-induced cardioprotection are still unclear. Thus, in this study, we clarified dose-dependent effects of EPO administered just before reperfusion on infarct size and the incidence of ventricular fibrillation and evaluated the involvement of the phosphatidylinositol-3 (PI3) kinase in the in vivo canine model. The canine left anterior descending coronary artery was occluded for 90 min followed by 6 h of reperfusion. A single intravenous administration of EPO just before reperfusion significantly reduced infarct size (high dose (1,000 IU/kg): 7.7 +/- 1.6%, low dose (100 IU/kg): 22.1 +/- 2.4%, control: 40.0 +/- 3.6%) in a dose-dependent manner. Furthermore, the high, but not low, dose of EPO administered as a single injection significantly reduced the incidence of ventricular fibrillation during reperfusion (high dose: 0%, low dose: 40.0%, control: 50.0%). An intracoronary administration of a PI3 kinase inhibitor, wortmannin, blunted the infarct size-limiting and anti-arrhythmic effects of EPO. Low and high doses of EPO equally induced Akt phosphorylation and decreased the equivalent number of TUNEL-positive cells in the ischemic myocardium of dogs. These effects of EPO were abolished by the treatment with wortmannin. In conclusion, EPO administered just before reperfusion reduced infarct size and the incidence of ventricular fibrillation via the PI3 kinase-dependent pathway in canine hearts. EPO administration can be a realistic strategy for the treatment of acute myocardial infarction.

[A role of magnesium: magnesium in the therapy for cardiovascular diseases].

Magnesium (Mg(2+)) is well known as a natural Ca channel blocker, and has various actions to benefit for the cardiovascular system. The point of action is culminated to (1) Ca antagonism, (2) beta-adrenoceptors blocking action, and (3) anti-platelet action. Because Mg(2+) is one of physiology materials, more ideal effect can be expected than Mg(2+). On the other hand, in the new large-scale clinical trial of acute myocardial infarction (MAGIC), Mg(2+) was not able to show the expected outcomes although Mg(2+) is an important co-factor of 5'-nucleotidase activity which is a production enzyme of adenosine and may show cardioprotective effect through adenosine production increase. Therefore, we must say that we need further investigation on the role of Mg(2+) on the cardiovascular protection.

Novel technique using intravascular ultrasound-guided guidewire cross in coronary intervention for uncrossable chronic total occlusions.

The experience of using a novel application of intravascular ultrasound (IVUS)-guided percutaneous coronary interventions for chronic total occlusions is reported in 2 cases. In the first case, an IVUS catheter was advanced into a side branch to identify the entry point of the major branch. In the second case, IVUS-guided penetration of the guidewire from the false lumen to the true lumen after causing a dissection was successful.

The influence of diabetes mellitus on plaque volume and vessel size in patients undergoing percutaneous coronary intervention.

We evaluated the influence of diabetes on plaque volume and vessel size at a reference segment in diabetic patients undergoing percutaneous coronary intervention using both angiograms and quantitative intravascular ultrasound. A total of 344 patients with 449 de novo coronary lesions including 97 diabetics (133 lesions) who underwent elective percutaneous coronary intervention under intravascular ultrasound guidance were included in this study. Eleven diabetic patients (19 lesions) received insulin and 52 patients (77 lesions) oral hypoglycemic drugs. The other 34 patients (37 lesions) received diet/exercise therapy alone. We measured vessel area (VA) and lumen area (LA) at proximal and distal reference segments by intravascular ultrasound, which were averaged. Plaque area (VA-LA) and % plaque area (100 x plaque area/VA) were subsequently calculated. Although VA was similar between diabetic and non-diabetic patients (13.46 +/- 4.49 mm2 in diabetics versus 14.11 +/- 5.24 mm2 in non-diabetics, P = 0.214), LA was smaller (6.51 +/- 2.63 mm2 versus 7.38 +/- 3.08 mm2, P = 0.004) and % PA was larger (50.4 +/- 11.7 versus 46.5 +/- 11.3, P < 0.001) in diabetic patients, especially the group receiving a hypoglycemic drug or insulin. VA, LA, and % PA were similar between patients with and without insulin treatment. These results potentially might cause undersized device selection without intravascular ultrasound guidance.

Intravenous administration of nifekalant hydrochloride for the prevention of ischemia-induced ventricular tachyarrhythmia in patients with renal failure undergoing hemodialysis.

Excretion in the urine is an important pathway for the elimination of nifekalant hydrochloride (NIF), a novel class III antiarrhythmic agent. Three patients with renal failure were undergoing hemodialysis and receiving NIF for the prevention of ischemia-induced ventricular tachyarrhythmia. Because NIF is not dialyzed, dose adjustment at relatively low concentrations was required, with monitoring of the QT interval.