Miki Fujii

A new-generation N/L-type calcium channel blocker leads to less activation of the renin-angiotensin system compared with conventional L type calcium channel blocker.

Objective Calcium channel blocker (CCB) is one of the most useful antihypertensive agents. However, the activation of the renin–angiotensin system (RAS) is an unfavorable characteristic. N-type calcium channel is thought to be involved in catecholamines release. Accordingly, N/L-type CCB has a probability of less activation of the RAS. We substantiated the hypothesis that N/L-type CCB, cilnidipine, leads to less activation of the RAS compared with conventional L-type CCB, amlodipine. Design Randomized, cross-over study. Setting Outpatient study. Participants Participants were 110 hypertensive patients [male/female 46/64, age 66.3 ± 10.8 years, systolic blood pressure (SBP)/diastolic blood pressure (DBP) 161.8 ± 16.9/92.9 ± 12.4 mmHg, s-Cr 0.77 ± 0.32 mg/dl, plasma renin activity (PRA) 0.65 ± 0.63 ng/ml per h, angiotensin I (AngI) 70.5 ± 77.3 pg/ml, angiotensin II (AngII) 5.2 ± 3.9 pg/ml, plasma aldosterone concentration (PAC) 76.3 ± 35.9 pg/ml, urinary albumin excretion (UAE) 108.1 ± 284.2 mg/gCr]. Amlodipine besilate or cilnidipine was administered for 12 weeks in a cross-over manner as a monotherapy with an intention-to-treat fashion by titrating doses. Final doses of amlodipine besilate and cilnidipine were 6.6 ± 2.7 and 13.7 ± 5.1 mg/day, respectively. Main outcome measures Changes in blood pressure, PRA, AngI, AngII, PAC, UAE of baseline and each end of amlodipine besilate and cilnidipine administration. Results Results were as follows (amlodipine vs. cilnidipine): SBP/DBP (mmHg): 135.2 ± 11.7/79.8 ± 9.6 vs. 136.7 ± 13.2/79.5 ± 10.9, P = 0.22/0.74; PRA (ng/ml per h): 1.16 ± 1.03 vs. 0.95 ± 0.78, P < 0.01; AngI (pg/ml): 155.0 ± 306.4 vs. 101.8 ± 92.0, P < 0.05; AngII (pg/ml): 12.0 ± 12.3 vs. 7.1 ± 4.5, P < 0.001; PAC (pg/ml): 81.6 ± 37.9 vs. 74.3 ± 36.2, P < 0.05; UAE (mg/gCr): 145.4 ± 424.5 vs. 58.8 ± 125.1, P < 0.05. Thus, in spite of the comparable blood pressure reductions, each level of components of the RAS at cilnidipine administration was significantly lower than those at amlodipine. Apart from this, UAE at cilnidipine administration was also significantly lower than that at amlodipine. Conclusion It is suggested that cilnidipine leads to less activation of the RAS compared with amlodipine for the first time in human clinical patients and therefore cilnidipine might be expected to be superior in organ protection in addition to the antialbuminuric effect.

Aldosterone inhibits endothelial morphogenesis and angiogenesis through the downregulation of vascular endothelial growth factor receptor-2 expression subsequent to peroxisome proliferator-activated receptor gamma

Angiogenesis plays a pivotal role in cardiovascular diseases such as ischemic heart disease, limb ischemia and heart failure, and has recently been shown to mediate various biological activities related to the pathogenesis of these diseases. In the present study, we evaluated the role of aldosterone in angiogenesis. Tube formation assay on Matrigel using human umbilical vein endothelial cells (HUVEC) revealed that aldosterone inhibited endothelial morphogenesis in a manner sensitive to eplerenone, a selective mineralocorticoid receptor antagonist. The anti-angiogenic effect of aldosterone was further confirmed by an in vivo angiogenesis assay using a Matrigel plug model in mice. Reverse transcription-mediated polymerase chain reaction and immunoblotting demonstrated that aldosterone downregulated the expression levels of vascular endothelial growth factor receptor-2 (VEGFR-2) and peroxisome proliferators-activated receptor gamma (PPAR gamma). VEGFR-2 expression was found to be enhanced in response to PPAR gamma activation by troglitazone, and attenuated by GW9662, a specific antagonist of PPAR gamma. In the tube formation assay, endothelial morphogenesis was stimulated by troglitazone, and inhibited by GW9662, indicating that PPAR gamma activation mediates positive regulation of angiogenesis through enhancement of VEGFR-2 expression. These data suggest that aldosterone inhibits angiogenesis through VEGFR-2 downregulation, subsequent to, at least in part, attenuation of PPAR gamma expression. The present findings provide a new insight into the possible therapeutic application of mineralocorticoid receptor blockade to various cardiovascular diseases.

A CROSS-OVER COMPARISON OF ANTI-ALBUMINURIC EFFECTS AMONG 4 TYPES CALCIUM CHANNEL BLOCKERS ON CHRONIC KIDNEY DISEASE: PP.33.310

Background and Objectives: At the intervention for hypertension with chronic kidney disease (CKD), albuminuria is one of the pivotal targets as well as strict blood pressure (BP) control for organ protection. Calcium channel blocker (CCB) is one of the most expected agents for CKD. Currently CCBs have been classified by half-life, drug delivery system and channel types. We tested anti-albuminuric effect and humoral factors level of 4 types of CCBs in CKD. Methods: Subjects were 50 hypertensives with CKD (male/female 22/28, age 69.8±10.8yrs, SBP/DBP 164.7±17.1/92.3±12.2 mmHg, s-Cr 0.81±0.37 mg/dl, urinary albumin excretion (UAE) 69.4 (33.5–142.6) mg/gCr). CCBs were administered for 12 weeks in a crossover manner. Tested agents were nifedipine CR, a long biological half-life L type CCB with controlled release system, cilnidipine, an N/L type CCB, efonidipine, a T/L type CCB and amlodipine, a long biological half-life L type CCB with trans-membrane approach. Results: Comparable BP reductions were obtained. UAE at endpoints ware as follow (mg/gCr, *P < 0.05): nifedipine CR 30.8 (17.3–81.1),* cilnidipine 33.9 (18.0–67.7),* efonidipine 51.0 (21.2–129.8), amlodipine 40.6 (18.7–94.7). By all agents, significant augmentations were observed in PRA, angiotensin I and angiotensin II (AngII). AngII at cilnidipine was significantly lower than that at amlodipine. PAC at cilnidipine and efonidipine was significantly lower than that at amlodipine. Nifedipine CR significantly reduced ANP concentration. Conclusions: It is revealed for the first time that, although all tested drugs reduced UAE, only nifedipine CR and cilnidipine could reach statistical difference. Thus, it is suggested that, in respect of albuminuria reduction, the 2 CCBs might be favorable for organ protection in CKD.

Determinants of plasma renin activity: role of a human renin gene variant as a genetic factor.

AbstractThe plasma renin activity (PRA) is affected by a number of environmental factors. However, significant heritability has been shown for the activity. A hypothesis that a candidate regulatory single-nucleotide polymorphism, C-5312T, of human renin gene should have a significant effect on PRA was elucidated and updating of independent determinants of PRA was attempted.Cross sectional study.Outpatient study.We enrolled consecutive 810 subjects who had consulted our hospitals for lifestyle-related diseases.Genotypes were assayed with genomic DNA for C-5312T. Among the genetic variants, the difference of PRA was evaluated. Monovariate linear regression analysis was performed to test the correlation between PRA and clinical variables. Finally, stepwise multiple regression analysis was performed to evaluate the independent determinants.On comparing 2 genotype groups, CC/CT and T allele homozygote, the geometric means of PRA were 0.778 and 0.941 ng/ml/h, respectively (F = 5.992, P = 0.015). Monovariate linear regression analysis revealed that a number of variables have a significant correlation with the activity, including urinary salt excretion. A stepwise multivariate regression analysis revealed that renin C-5312T variant (TT) is one of the independent determinants of PRA.Thus, for the first time, a human renin gene variant was associated with a significant increase in PRA as a genetic factor and the independent determinants for the activity were updated including genetic factor.

A crossover comparison of urinary albumin excretion as a new surrogate marker for cardiovascular disease among 4 types of calcium channel blockers

BACKGROUND At the intervention for cardiovascular disease (CVD), albuminuria is a new pivotal target. Calcium channel blocker (CCB) is one of the most expected agents. Currently CCBs have been classified by delivery system, half-life and channel types. We tested anti-albuminuric effect among 4 types of CCBs. METHODS Subjects were 50 hypertensives (SBP/DBP 164.7±17.1/92.3±12.2mmHg, s-Cr 0.81±0.37mg/dl, urinary albumin excretion (UAE) 69.4 (33.5-142.6) mg/gCr). Four CCBs were administered in a crossover setting: nifedipine CR, a long biological half-life L type by controlled release; cilnidipine, an N/L type; efonidipine, a T/L type; and amlodipine, a long biological half-life L type. RESULTS Comparable BP reductions were obtained. UAE at endpoints ware as follows (mg/gCr, *P<0.01): nifedipine CR 30.8 (17.3-81.1),* cilnidipine 33.9 (18.0-67.7),* efonidipine 51.0 (21.2-129.8), amlodipine 40.6 (18.7-94.7). By all agents, significant augmentations were observed in PRA, angiotensin I and angiotensin II (AngII). AngII at cilnidipine was significantly lower than that at amlodipine. PAC at cilnidipine and efonidipine was significantly lower than that at amlodipine. Nifedipine CR significantly reduced ANP concentration. CONCLUSIONS It is revealed that only nifedipine CR and cilnidipine could reduce albuminuria statistically. Thus, it is suggested that the 2 CCBs might be favorable for organ protection in hypertensives.

Differential effects of α-glucosidase inhibitors on postprandial plasma glucose and lipid profile in patients with type 2 diabetes under control with insulin lispro mix 50/50.

BACKGROUND The additive effect of α-glucosidase inhibitors (α-GIs) was investigated in patients with type 2 diabetes (T2D) under control with rapid-acting insulin analog. SUBJECTS AND METHODS Thirty-six poorly controlled T2D patients were recruited, and plasma glucose (PG) was controlled by three times daily injection of insulin lispro mix 50/50 (Mix50) to maintain fasting PG <130 mg/dL and 2-h postprandial PG (PPG) <180 mg/dL. Another group of 20 patients was randomly assigned to either 0.3 mg of voglibose or 50 mg of miglitol, which was administered at breakfast every other day. Another group of 16 patients was assigned to a crossover study, in which each α-GI was switched every day during the 6-day study. PPG, C-peptide, and lipid profile were analyzed. RESULTS The addition of voglibose had no effect on PPG, but miglitol blunted the PPG rise and significantly decreased 1-h and 2-h postprandial C-peptide levels compared with Mix50 alone. In addition, miglitol significantly decreased the 1-h postprandial triglyceride rise and the remnant-like particle-cholesterol rise, while it increased the 1-h postprandial high-density lipoprotein-cholesterol and apolipoprotein A-I levels in the crossover study. CONCLUSIONS Miglitol appears to have rapid action, which appears earlier than that of lispro. The combination of miglitol and Mix50 seems effective for the control of PPG and lipid profile in T2D.

Immediate effect of subliminal priming with positive reward stimuli on standing balance in healthy individuals: A randomized controlled trial

Background: Information received subconsciously can influence exercise performance; however, it remains unclear whether subliminal or supraliminal reward is more effective in improving standing balance ability when priming stimuli are subconsciously delivered. The present study aimed to compare the effects of subliminal priming-plus-subliminal reward stimuli (experimental) with subliminal priming-plus-supraliminal reward stimuli (control) on standing balance ability. Methods: This was a single-blind (outcome assessor), parallel-group, randomized controlled trial involving healthy young adults recruited from a university in Japan. Assessments were conducted at baseline and immediately after intervention. The primary outcome was the functional reach test (FRT) measurement. The secondary outcome was one-leg standing time (OLST) with eyes closed. Of the 52 participants screened, 25 were randomly assigned to experimental and control groups each. Results: Both interventions were effective for improving the FRT between the baseline and intervention; however, smaller improvements were observed in the experimental group. We found a large between-groups effect size immediately after the intervention for the FRT (d = −0.92). In contrast, there were no differences in improvements in OLST between the 2 groups (d = −0.06); furthermore, neither intervention was found to be effective for this parameter. Conclusion: We concluded that subliminal priming with conscious reward stimuli results in improvements in immediate-term forward reach ability, which is superior to that achieved by subliminal priming with subconscious reward stimuli.

ASSOCIATION STUDY OF URIC ACID TRANSPORTER GLUT9 GENOTYPE WITH THE RENIN-ANGIOTENSIN SYSTEM

Objective: Uric acid is thought to be one of risk factors for atherosclerotic disorders. The mechanisms have been thought to include endothelial dysfunction, inflammation, oxidative stress and the renin angiotensin system (RAS) activation. It is known that the RAS plays a pivotal role in the atherosclerotic disorders. However, the evidence that uric acid is involved in the activation is not sufficient. We therefore tested the hypothesis that a genetic variant of a uric acid transporter, glucose transporter 9 (GLUT9) could show significant association with prevalence of hyper-reninemic state. Design and method: We enrolled consecutive 804 subjects who had consulted our hospitals for life style related diseases (statistic power 80%, significance level 0.05). We defined the subjects with plasma renin activity (PRA) equal with or more than 0.70 mg/ml/hr. as hyper-reninemic group as cases of the study and the subjects with PRA less than 0.70 mg/ml/hr as normo-reninemic group as controls. Genomic DNA was isolated from human leukocytes. Genotypes were assayed with genomic DNA for a C/T variant of GLUT9 (rs1014290) using real-time PCR system by TaqMan method. Association between the genetic variant and the prevalence of hyper-reninemic state was tested. Results: They consisted of cases (51.0%) and controls (49.0%). The serum uric acid (mg/dl) with each genotype of GLUT9 were as follows: CC (127 cases) 5.04 ± 1.45, CT (392 cases) 5.08 ± 1.49, TT (286 cases) 5.44 ± 1.45 (CC vs CT, p = 0.77; CC vs TT, p = 0.011; CT vs TT, p = 0.002). The numbers of individuals with each genotype were as follows (CC, CT and TT): 52, 204 and 154 for cases and 75, 187 and 132 for controls. Accordingly, the risk for hyper-reninemic state was 1.24 (95% confidence interval; 1.02–1.52), p = 0.033 for allelic comparison and also p = 0.032 for Armitages trend test, the T allele being the risk allele. Conclusions: The uric acid concentration is associated with a genetic variant of transporter GLUT9 and the subjects with genetic variant of high uric acid have hyper-reninemic constitution. Thus, from a view point of Mendelian randomization theory, it is found that high uric acid state may have a significant impact on the RAS activation.

GENETIC VARIATION IN THE RENIN-ANGIOTENSIN-ALDOSTERONE SYSTEM AND RENAL SURVIVAL IN JAPANESE PATIENTS WITH DIABETIC NEPHROPATHY

Objective: Genetic polymorphisms of the renin-angiotensin-aldosterone system (RAAS) may play a pivotal role in the development and progression of diabetic nephropathy. Therefore, we aimed to investigate whether genetic variation in the RAAS is related to renal survival in patients with diabetic nephropathy. Design and method: We enrolled 246 Japanese patients with diabetic nephropathy who consulted nephrologists in our hospital between January 1995 and December 2010. One hundred and fifty-three (62.2%) patients progressed to end stage renal disease (ESRD) at an average age of 63.8 years. We estimated the association between 5 polymorphisms of RAAS and cumulative renal survival. We investigated the following genetic polymorphisms: renin enhancer region (REN) C-5312T, angiotensinogen M235T, angiotensin converting enzyme (ACE) insertion/deletion, angiotensin II type I receptor A1166C, and aldosterone synthase CYP 11B2 C-344T. We used cumulative survival analysis using the Kaplan–Meier method with the log-rank test for statistical analysis of the time course of progression to ESRD. Results: Cumulative renal survival in diabetic nephropathy was significantly lower in those with the DD/DI genotype of the ACE I/D polymorphism (log-rank, P = 0.038; X2 = 4.298). There was no association between cumulative survival and the REN C-5312T, M235T, A1166C, and C-344T polymorphisms. Conclusions: The ACE I/D polymorphism may play a role in diabetic nephropathy progression in that it may directly affect prognosis in these patients.

[OP.6D.04] ASSOCIATION STUDY OF ANGIOTENSINASE A (ENPEP) GENOTYPE WITH DIABETIC NEPHROPATHY.

Objective: It is well known that the renin angiotensin system (RAS) plays a pivotal role in the development of diabetic nephropathy (DMN). Recent genome-wide association studies have identified a number of common genetic variants associated with blood pressure variation in east Asians. One of such loci is angiotensinase A (ENPEP), which converts the angiotensin II to angiotensin III in the RAS. We therefore tested the hypothesis that genetic variants of ENPEP could show significant association with prevalence of DMN. Design and method: We enrolled consecutive 345 subjects who had consulted our hospitals for type 2 diabetes. They consisted of cases with nephropathy (57.1 %) and controls (42.9%). Genomic DNA was isolated from human leukocytes by QIAamp kit. Genotypes were assayed with genomic DNA for a C/T variant of ENPEP (rs6825911) using the StepOnePlus real-time PCR system by TaqMan method. Association between the genetic variant and the prevalence of DMN was tested. Results: The numbers of individuals with each genotype of ENPEP were as follows (CC, CT and TT): 64, 93 and 40 for cases and 29, 84 and 35 for controls. Accordingly, the risk for DMN was 1.39 (95% confidence interval; 1.02–1.88), p = 0.03 for allelic comparison and also p = 0.03 for Armitages trend test. Thus, a significant association with DMN was observed for the ENPEP variant with 1.4 times risk. Conclusions: Thus, it is found that a genetic variant of ENPEP may have a significant impact on the onset of DMN.