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Renal denervation (RDN) has emerged as a novel therapy for drug-resistant hypertension. We here examined the effects of RDN at early versus advanced stages of hypertension on blood pressure and organ pathology in rats with salt-sensitive hypertension. Dahl salt-sensitive (DahlS) rats fed an 8% NaCl diet from 6 weeks of age were subjected to RDN (surgical ablation and application of 10% phenol in ethanol) or sham surgery at 7 (early stage) or 9 (advanced stage) weeks and were studied at 12 weeks. RDN at early or advanced stages resulted in a moderate lowering of blood pressure. Although RDN at neither stage affected left ventricular (LV) and cardiomyocyte hypertrophy, it ameliorated LV diastolic dysfunction, fibrosis, and inflammation at both stages. Intervention at both stages also attenuated renal injury as well as downregulated the expression of angiotensinogen and angiotensin-converting enzyme (ACE) genes and angiotensin II type 1 receptor protein in the kidney. Furthermore, RDN at both stages inhibited proinflammatory gene expression in adipose tissue. The early intervention reduced both visceral fat mass and adipocyte size in association with downregulation of angiotensinogen and ACE gene expression. In contrast, the late intervention increased fat mass without affecting adipocyte size as well as attenuated angiotensinogen and ACE gene expression. Our results thus indicate that RDN at early or late stages after salt loading moderately alleviated hypertension and substantially ameliorated cardiac and renal injury and adipose tissue inflammation in DahlS rats. They also suggest that cross talk among the kidney, cardiovascular system, and adipose tissue may contribute to salt-sensitive hypertension. Supposed mechanism for the beneficial effects of RDN on hypertension and target organ damage in DahlS rats. RDN at early or late stages after salt loading moderately alleviated hypertension and substantially ameliorated renal injury in DahlS rats. Cross talk among the kidney, cardiovascular system, and adipose tissue possibly mediated by circulating RAS may contribute to salt-sensitive hypertension. LV; left ventricular, NE; norepinephrine, RAS; renin-angiotensin system, RDN; renal denervation., (© 2024. The Author(s).)

In this comprehensive state-of-the-art review, we provide an evidence-based analysis of current drug therapies for patients with heart failure with preserved ejection fraction (HFpEF) in the acute and chronic phases with concurrent hypertension. Additionally, we explore the latest developments and emerging evidence on the efficacy, safety, and clinical outcomes of common and novel drug treatments in the management of HFpEF with concurrent hypertension. During the acute phase of HFpEF, intravenous diuretics, mineralocorticoid receptor antagonists (MRAs), and vasodilators are pivotal, while in the chronic phase, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have proven effective in enhancing clinical outcomes. However, the use of calcium channel blockers in HFpEF with hypertension should be approached with caution, owing to their potential negative inotropic effects. We also explored emerging drug therapies for HFpEF, such as sodium-glucose co-transporter 2 (SGLT2) inhibitors, angiotensin receptor-neprilysin inhibitor (ARNI), soluble guanylate cyclase (sGC) stimulators, novel MRAs, and ivabradine. Notably, SGLT2 inhibitors have shown promise in reducing heart failure hospitalizations and cardiovascular mortality in patients with HFpEF, regardless of their diabetic status. Additionally, ARNI and sGC stimulators have demonstrated potential in improving symptoms, functional capacity, and quality of life. Nonetheless, additional research is necessary to pinpoint optimal treatment strategies for HFpEF with concurrent hypertension. Furthermore, long-term studies are essential to assess the durability and sustained benefits of emerging drug therapies. Identification of novel targets and mechanisms underlying HFpEF pathophysiology will pave the way for innovative drug development approaches in the management of HFpEF with concurrent hypertension., (© 2024. The Author(s).)

Background: Intravenous vasodilators are commonly used in patients with hypertensive acute decompensated heart failure (ADHF), but little is known about their optimal use in blood pressure (BP) management to avoid acute kidney injury (AKI). The purpose of this study was to investigate the association between systolic BP (SBP) changes and the incidence of AKI in patients with hypertensive ADHF., Methods and results: Post-hoc analysis was performed on a prospectively enrolled cohort. We investigated 245 patients with ADHF and SBP >140 mmHg on arrival (mean age, 76 years; 40% female). We defined "SBP-fall" as the maximum percent reduction in SBP 6 h after intravenous treatment. AKI was defined as serum creatinine (SCr) ≥0.3 mg/dL, or urine output <0.5 mL/kg/h (n=66) at 48 h. Mean SBP and SCr levels on arrival were 180 mmHg and 1.21 mg/dL, respectively. Patients with AKI had significantly larger SBP-fall than the others (36.7±15.3% vs. 27.2±15.3%, P<0.0001). Logistic regression analysis showed an odds ratio per 10% SBP-fall for AKI of 1.49 (95% confidence interval 1.29-1.90, P=0.001). SBP-fall was significantly associated with the number of concomitant used intravenous vasodilators (P=0.001). The administration of carperitide was also independently associated with increased incidence of AKI., Conclusions: Larger SBP-fall from excessive vasodilator use is associated with increased incidence of AKI in patients with hypertensive ADHF.

Angiotensin-converting enzyme inhibitors (ACEIs) are considered primary drugs for the secondary prevention of myocardial infarction (MI), and angiotensin receptor blockers (ARBs) are used when ACEIs cannot be tolerated. However, it is unclear whether ACEIs or ARBs are more appropriate first-line drugs in hypertensive patients with MI or heart failure (HF). The present study aimed to compare the effects of ACEIs and those of ARBs in these patients. Sixty randomized controlled trails (RCTs) that compared the effects of ACEIs and ARBs in patients with MI or HF were extracted by searching PubMed/MEDLINE, Cochrane Database, and the Medical Central Journal database according to the PRISMA guidelines. We finally selected six eligible RCTs and identified three systematic reviews and meta-analyses. The proportion of hypertensive patients ranged from 36 to 69%. Meta-analyses were performed for recurrence or new onset of MI (risk ratio 0.97 [95% confidence interval: 0.88, 1.06]), hospitalization for HF (0.98 [0.84, 1.14]), cardiovascular or total mortality (0.98 [0.91, 1.05]), cardiovascular events or stroke (1.02 [0.94, 1.11]), and adverse events (1.40 [1.11, 1.77]). There were no significant differences between ACEIs and ARBs for all outcomes, except adverse events. Study discontinuation owing to adverse events was significantly more common with ACEIs than with ARBs. Among hypertensive patients with MI or HF, it appears desirable to select the most appropriate drugs, ACEIs or ARBs, in each case by considering the function level, patient background, comorbidity presence, blood pressure target, drug price and other such factors comprehensively in addition to considering tolerability.

Cardiovascular disease (CVD) is the greatest cause of death, accounting for nearly one-third of all deaths worldwide. The increase in obesity rates over 3 decades is widespread and threatens the public health in both developed and developing countries. Obesity, the excessive accumulation of visceral fat, causes the clustering of metabolic disorders, such as type 2 diabetes, dyslipidemia, and hypertension, culminating in the development of CVD. Adipose tissue is not only an energy storage organ, but an active endocrine tissue producing various biologically active proteins known as adipokines. Since leptin, a central regulator of food intake and energy expenditure, was demonstrated to be an adipose-specific adipokine, attention has focused on the identification and characterization of unknown adipokines to clarify the mechanisms underlying obesity-related disorders. Numerous adipokines have been identified in the past 2 decades; most adipokines are upregulated in the obese state. Adipokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and resistin are pro-inflammatory, and exacerbate various metabolic and cardiovascular diseases. However, a small number of adipokines, including adiponectin, are decreased by obesity, and generally exhibit antiinflammatory properties and protective functions against obesity-related diseases. Collectively, an imbalance in the production of pro- and antiinflammatory adipokines in the obese condition results in multiple complications. In this review, we focus on the pathophysiologic roles of adipokines with cardiovascular protective properties.

Background: Serum uric acid level is a predictor of future hypertension. However, its dependence on body mass index or age is unclear., Methods: We examined 26,442 Japanese males aged 18-60years free from hypertension or diagnosed cardiovascular disease at baseline followed up between 2000 and 2010. Participants were categorized into three groups according to the tertile of serum uric acid levels [mg/dL; 1st (reference): 0.1-5.3; 2nd: 5.4-6.2; 3rd: 6.3-11.6]. Incident hypertension was defined as newly detected blood pressure≥140/90mmHg and/or antihypertensive drugs initiation. Body mass index (<25kg/m(2) vs. ≥25kg/m(2)) and age (<40years vs. ≥40years) were stratified into two groups., Results: During a mean follow-up of 7.2years, there were 11,361 (43%) hypertension cases. Mean serum uric acid levels (mg/dL) at baseline in each group were 1st tertile, 4.6; 2nd tertile, 5.8; and 3rd tertile, 7.0. The cumulative incident hypertension rate was significantly higher in the 3rd tertile (50.8%) than in the 1st (37.4%). Multiple-adjusted hazard ratios (95% confidence interval) for incident hypertension compared with 1st tertile were 1.01 (0.96-1.05) and 1.15 (1.10-1.21) in the 2nd and 3rd tertile, respectively. There was a significant interaction between age and serum uric acid level (p for interaction=0.035). In subjects aged ≥40years, the 3rd serum uric acid group showed higher hazard ratios [1.48 (1.38-1.59)]., Conclusion: High serum uric acid level was associated with future hypertension in young and middle-aged Japanese males. This association was stronger among subjects ≥40years old., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: To address the impact of antidiabetic drugs on cardiovascular safety is a matter of clinical concern. Preclinical studies revealed that various protective effects of dipeptidyl peptidase-4 inhibitor (DPP4i) on cardiovascular disease; however, its impact of on hypertension remains controversial., Methods and Results: Teneligliptin (TEN; 10mg/kg/day/p.o.) ameliorates hypertension and cardiac remodeling by normalizing a rise of angiotensin-II (AngII) that specifically observed in spontaneously hypertensive rats (SHR). TEN had no effects on vasculature and concentrations of the DPP4-related vasoactive peptides (bradykinin, neuropeptide Y, and atrial natriuretic peptide). The primary action of TEN on BP lowering was due to restoring the AngII-induced manifestation of congestive heart failure observed in SHR. Sodium-proton pump exchanger type 1 (NHE-1) is a regulator of intracellular acidity (pHi) and implicated pathophysiological role in cardiac remodeling occurred in diseased myocardium. Cardiac NHE-1 expression level was increased in SHR and this was restored in TEN-treated SHR. AngII directly augmented cardiac NHE-1 expression and its activity that contributed to hypertrophic response. TEN attenuated the AngII-induced cardiac hypertrophy with decline in pHi via suppression of NHE-1. Loss of NHE-1 activity by specific inhibitor or RNA silencing promoted intracellular acidification and consistently attenuated the AngII-mediated cardiac hypertrophy., Conclusion: The present study revealed the protective actions of TEN on hypertension and comorbid cardiac remodeling via AngII/NHE-1 axis and the novel pathophysiological roles of intracellular acidification via NHE-1 in cardiac hypertrophy., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Aim: Cerebral white matter hyperintensity (WMH) is highly prevalent in the elderly population, and increases the risk of dementia and stroke. We investigated the relationship between ambulatory blood pressure monitoring levels and quantitatively measured WMH volumes among elderly hypertensive patients with well-controlled blood pressure (BP) to re-evaluated effective hypertension management methods to prevent the progression of WMH., Methods: Participants comprised 84 hypertensive patients aged between 65 and 75 years without symptomatic heart failure, ischemic heart disease, atrial fibrillation, stroke or cognitive dysfunction., Results: Linear regression analysis showed that office BP was not associated with WMH volume increases. Raised night-time systolic BP (P = 0.013) were associated with greater WMH volumes during ambulatory blood pressure monitoring. To clarify the effect of asleep systolic BP on WML volume, we then classified patients into two systolic BP groups as follows: <125 mmHg (n = 47) and ≥125 mmHg (n = 37). Baseline characteristics were almost similar in both groups, except the dipper type of circadian BP variation was significantly common in the group with night-time systolic BP <125 mmHg. However, WMH volume was greater in the group with night-time systolic BP ≥125 mmHg than that in the <125 mmHg group (9.0 ± 8.4 mL vs 4.1 ± 4.3 mL, P = 0.015)., Conclusion: Higher night-time systolic BP levels were observed to contribute greater WMH volumes in elderly hypertensive patients. To prevent the progression of WMH, controlling BP on the basis of ambulatory blood pressure monitoring is important., (© 2015 Japan Geriatrics Society.)

Angiotensin receptor blockers (ARBs) are often supplemented with calcium channel blockers (CCBs) for treatment of hypertension. We recently showed that the L/N-type CCB cilnidipine has superior cardioprotective effects compared with the L-type CCB amlodipine in Dahl salt-sensitive (DS) rats. We have now compared the effects of the ARB valsartan combined with cilnidipine or amlodipine on cardiac pathophysiology in DS rats. DS rats fed a high-salt diet from 6 weeks of age were treated with vehicle, valsartan alone (10 mg kg(-1) per day), or valsartan combined with either cilnidipine (1 mg kg(-1) per day) or amlodipine (1 mg kg(-1) per day) from 7 to 11 weeks. The salt-induced increase in systolic blood pressure apparent in the vehicle group was attenuated similarly in the three drug treatment groups. Valsartan-cilnidipine attenuated left ventricular (LV) fibrosis and diastolic dysfunction as well as cardiac oxidative stress and inflammation to a greater extent than did valsartan alone or valsartan-amlodipine. In addition, the increases in urinary excretion of dopamine and epinephrine as well as in cardiac renin-angiotensin-aldosterone-system (RAAS) gene expression apparent in vehicle-treated rats were attenuated to a greater extent by valsartan-cilnidipine than by the other two treatments. Valsartan-cilnidipine thus attenuated LV remodeling and diastolic dysfunction more effectively than did valsartan or valsartan-amlodipine in rats with salt-sensitive hypertension, and this superior cardioprotective action of valsartan-cilnidipine compared with valsartan-amlodipine is likely attributable, at least in part, to the greater antioxidant and antiinflammatory effects associated with both greater inhibition of cardiac RAAS gene expression and N-type calcium channel blockade.

Background: Metabolic syndrome (MetS) enhances salt sensitivity of blood pressure and is an important risk factor for cardiovascular disease. The effects of dietary salt restriction on cardiac pathology associated with metabolic syndrome remain unclear., Methods and Results: We investigated whether dietary salt restriction might ameliorate cardiac injury in DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, which are derived from a cross between Dahl salt-sensitive and Zucker rats and represent a model of metabolic syndrome. DS/obese rats were fed a normal-salt (0.36% NaCl in chow) or low-salt (0.0466% NaCl in chow) diet from 9 weeks of age and were compared with similarly treated homozygous lean littermates (DahlS.Z-Lepr(+)/Lepr(+), or DS/lean rats). DS/obese rats fed the normal-salt diet progressively developed hypertension and showed left ventricular hypertrophy, fibrosis, and diastolic dysfunction at 15 weeks. Dietary salt restriction attenuated all of these changes in DS/obese rats. The levels of cardiac oxidative stress and inflammation and the expression of cardiac renin-angiotensin-aldosterone system genes were increased in DS/obese rats fed the normal-salt diet, and dietary salt restriction downregulated these parameters in both DS/obese and DS/lean rats. In addition, dietary salt restriction attenuated the increase in visceral adipose tissue inflammation and the decrease in insulin signaling apparent in DS/obese rats without reducing body weight or visceral adipocyte size. Dietary salt restriction did not alter fasting serum glucose levels but it markedly decreased the fasting serum insulin concentration in DS/obese rats., Conclusions: Dietary salt restriction not only prevents hypertension and cardiac injury but also ameliorates insulin resistance, without reducing obesity, in this model of metabolic syndrome., (© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Objective: To investigate the independent associations of proteinuria and the estimated glomerular filtration rate (eGFR) with incident hypertension., Methods: We investigated 29,181 Japanese males 18-59years old without hypertension in 2000 and examined whether proteinuria and the eGFR predicted incident hypertension independently over 10years. Incident hypertension was defined as a newly detected blood pressure of ≥140/90mmHg and/or the initiation of antihypertensive drugs. Proteinuria and the eGFR were categorized as dipstick negative (reference), trace or ≥1+ and ≥60 (reference), 50-59.9 or <50ml/min/1.73m(2), respectively. Cox proportional hazards models were used to estimate the hazard ratios (HRs) of incident hypertension., Results: At baseline, 236 (0.8%) and 477 (1.6%) participants had trace and ≥1+ dipstick proteinuria, while 1416 (4.9%) and 129 (0.4%) participants had an eGFR of 50-59.9 and <50ml/min/1.73m(2), respectively. The adjusted HRs were significant for proteinuria ≥1+ (HRs 1.20, 95% CI: 1.06-1.35) and an eGFR of <50ml/min/1.73m(2) (1.29, 1.03-1.61). When two non-referent categories were combined (dipstick≥trace vs. negative and eGFR<60 vs. ≥60ml/min/1.73m(2)), the association was more significant for proteinuria (1.15, 1.04-1.27) than for eGFR (0.99, 0.92-1.07)., Conclusions: Proteinuria and a reduced eGFR are independently associated with future hypertension in young to middle-aged Japanese males., (Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.)

We previously showed that selective mineralocorticoid receptor (MR) blockade by eplerenone is cardioprotective in Dahl salt-sensitive (DS) rats. To clarify the consequences of glucocorticoid-mediated MR activation in these animals, we investigated the effects of exogenous corticosterone on blood pressure as well as cardiac remodeling and function after adrenalectomy. DS rats were subjected to adrenalectomy at 6 weeks of age and thereafter fed a high-salt diet and administered corticosterone (20 mg/kg per day) or vehicle. Systolic blood pressure was higher in the corticosterone group than in the vehicle group at 7 weeks and thereafter. By 11 weeks, corticosterone had reduced left ventricular (LV) mass and induced LV diastolic dysfunction. The ratio of collagen type I to type III mRNA levels in the left ventricle was increased in the corticosterone group compared with the vehicle group. Administration of a non-antihypertensive dose of the MR antagonist spironolactone (20 mg/kg per day) from 6 weeks inhibited the effects of corticosterone on both the collagen type I to type III mRNA ratio and diastolic function without affecting the decrease in LV mass. Spironolactone attenuated both the increase in NADPH oxidase activity in the left ventricle and coronary vascular inflammatory responses apparent in the corticosterone group. These results indicate that exogenous glucocorticoids induce hypertension, cardiac remodeling, and diastolic dysfunction in adrenalectomized DS rats fed a high-salt diet. The cardiac effects of exogenous glucocorticoids are likely attributable, at least in part, to myocardial oxidative stress and coronary vascular inflammation induced by glucocorticoid-activated MRs.

The apelin/APJ system has been implicated in obesity-related hypertension. We investigated the mechanism responsible for the pathogenesis of obesity-related hypertension with a special focus on the crosstalk between AngII/its type 1 receptor (AT1R) signaling and apelin/APJ expression. Sprague-Dawley rats fed a high-fat (obesity-related hypertension, OH) or normal-fat diet (NF) for 15 weeks were randomly assigned to one of two groups and administered vehicle or perindopril for 4 weeks. Compared to the NF rats, the OH rats showed lower levels of plasma apelin and apelin/APJ mRNAs of perirenal adipose tissues, and these changes were restored by perindopril. Administration of the AT1R antagonist olmesartan resulted in the restoration of the reduction of apelin and APJ expressions induced by AngII for 48 h in 3T3-L1 adipocytes. Among several inhibitors for extracellular signal-regulated kinases 1/2 (ERK1/2) PD98059, p38 mitogen-activated protein kinase (p38MAPK) SB203580 and phosphatidylinositol 3-kinase (PI3K) LY294002, the latter showed an additive effect on AngII-mediated inhibitory effects. In addition, the levels of p-Akt, p-ERK and p38MAPK proteins were decreased by long-term treatment with AngII (120 min), and these changes were restored by Olmesartan. Apelin/APJ appears to be impaired in obesity-related hypertension. The AngII inhibition-mediated beneficial effects are likely attributable, at least in part, to restoration of p38/ERK-dependent apelin/APJ expression in diet-induced obesity-related hypertension.

Recently, we reported that angiotensin II receptor blocker (ARB), valsartan, and calcium channel blocker (CCB), amlodipine, had similar effects on the prevention of cardiovascular disease (CVD) events in diabetic hypertensive patients. We assessed the difference of cardiovascular protective effects between ARB and CCB in patients with and without previous CVD, respectively. A total of 1,150 Japanese diabetic hypertensive patients were randomized to either valsartan or amlodipine treatment arms, which were additionally divided into 2 groups according to the presence of previous CVD at baseline (without CVD, n = 818; with CVD, n = 332). The primary composite outcomes were sudden cardiac death, acute myocardial infarction, stroke, coronary revascularization, or hospitalization for heart failure. The incidence of primary end point events in patients with previous CVD was 3.5-times greater than that in patients without previous CVD (64.1 vs 17.9/1,000 person-years). The ARB- and the CCB-based treatment arms showed similar incidence of composite CVD events in both patients without previous CVD (hazard ratio [HR] 1.35, 95% confidence interval [CI] 0.76 to 2.40) and those with previous CVD (HR 0.79, 95% CI 0.48 to 1.31). The ARB-treatment arm showed less incidence of stroke compared with the CCB-based treatment arm in patients with previous CVD (HR 0.24, 95% CI 0.05 to 1.11, p = 0.068), whereas the 2 treatment arms showed similar incidence of stroke in patients without previous CVD (HR 1.52, 95% CI 0.59 to 3.91). In conclusion, the ARB- and the CCB-based treatments exerted similar protective effects of CVD events regardless of the presence of previous CVD. For stroke events, the ARB may have more protective effects than the CCB in diabetic hypertensive patients with previous CVD., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Calorie restriction (CR) can modulate the features of obesity-related metabolic and cardiovascular diseases. We have recently characterized DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of metabolic syndrome. DS/obese rats develop hypertension and manifest left ventricular remodeling and diastolic dysfunction, as well as increased cardiac oxidative stress and inflammation. We have now investigated the effects of CR on cardiac pathophysiology in DS/obese rats. DS/obese rats were fed either normal laboratory chow ad libitum or a calorie-restricted diet (65% of the average food intake for ad libitum) from 9 to 13 weeks. Age-matched homozygous lean (DahlS.Z-Lepr(+)/Lepr(+) or DS/lean) littermates served as controls. CR reduced body weight in both DS/obese and DS/lean rats, as well as attenuated the development of hypertension in DS/obese rats without affecting blood pressure in DS/lean rats. CR also reduced body fat content, ameliorated left ventricular hypertrophy, fibrosis, and diastolic dysfunction, and attenuated cardiac oxidative stress and inflammation in DS/obese rats. In addition, it increased serum adiponectin concentration, as well as downregulated the expression of angiotensin-converting enzyme and angiotensin II type 1A receptor genes in the heart of DS/obese rats. Our results thus show that CR attenuated obesity and hypertension, as well as left ventricular remodeling and diastolic dysfunction in DS/obese rats, with these latter effects being associated with reduced cardiac oxidative stress and inflammation.

Glucocorticoids are widely administered for the treatment of various disorders, although their long-term use results in adverse effects associated with glucocorticoid excess. We investigated the pathophysiological roles of glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs) in the cardiac changes induced by exogenous corticosterone in rats. Corticosterone or vehicle was injected twice daily in rats from 8 to 12 weeks of age. The effects of the GR antagonist RU486, the MR antagonist spironolactone, or both agents on corticosterone action were also determined. Corticosterone induced hypertension, left ventricular (LV) fibrosis, and LV diastolic dysfunction. Neither RU486 nor spironolactone affected corticosterone-induced hypertension, whereas spironolactone, but not RU486, attenuated the effects of corticosterone on LV fibrosis and diastolic function. Corticosterone also increased cardiac oxidative stress and inflammation in a manner sensitive to spironolactone but not to RU486. The corticosterone-induced LV atrophy was not affected by either RU486 or spironolactone. Our results implicate MRs in the cardiac fibrosis and diastolic dysfunction, but not MRs or GRs in the cardiac atrophy, induced by corticosterone. Neither MRs nor GRs appear to contribute to corticosterone-induced hypertension.

Daily consumption of garlic is known to lower the risk of hypertension and ischemic heart disease. In this study, we examined whether aged garlic extract (AGE) prevents hypertension and the progression of compensated left ventricular (LV) hypertrophy in Dahl salt-sensitive (DS) rats. DS rats were randomly divided into three groups: those fed an 8% NaCl diet until 18 weeks of age (8% NaCl group), those additionally treated with AGE (8% NaCl + AGE group), and control rats maintained on a diet containing 0.3% NaCl until 18 weeks of age (0.3% NaCl group). AGE was administered orally by gastric gavage once a day until 18 weeks of age. LV mass was significantly higher in the 8% NaCl + AGE group than in the 0.3% NaCl group at 18 weeks of age, but significantly lower in the 8% NaCl + AGE group than in the 8% NaCl group. No significant differences were observed in systolic blood pressure (SBP) between the 8% NaCl and 8% NaCl + AGE groups at 12 and 18 weeks of age. LV end-diastolic pressure and pressure half-time at 12 and 18 weeks of age were significantly lower in the 8% NaCl + AGE group compared with the 8% NaCl group. AGE significantly reduced LV interstitial fibrosis at 12 and 18 weeks of age. Chronic AGE intake attenuated LV diastolic dysfunction and fibrosis without significantly decreasing SBP in hypertensive DS rats.

Although the circadian variation of catecholamine has been reported, that of the pulse wave velocity (PWV) has not. Brachial ankle (ba) PWV is associated with well-established indices of central stiffness. It is not known whether arterial stiffness is associated with catecholamine. The aim of the present study was to evaluate the changes in baPWV and those on the plasma epinephrine and norepinephrine levels in the morning and evening in hypertensive patients (HPs) and normotensive subjects (NSs). The baPWV and blood pressure (BP) were measured in 14 NSs (14 males, 39 ± 5 years) and 10 HPs (9 males and 1 female, 55 ± 13 years) at 06:00 h, noon, 18:00 h, and midnight, respectively. The plasma epinephrine and norepinephrine levels were measured in 14 NSs and 5 HPs at 06:00 h and 18:00 h, respectively. There was no significant difference in BPs at 06:00 h, noon, 18:00 h, and midnight in either NSs or HPs. The baPWV at 06:00 h was significantly lower than that at noon, 18:00 h, and midnight in NSs (P = 0.01, 0.04, and 0.0008, respectively). The plasma epinephrine and norepinephrine levels at 06:00 h were markedly lower than those at 18:00 h in NSs (P = 0.002 and 0.003, respectively). There were no significant changes in the baPWV of HPs at 06:00 h, noon, 18:00 h, or midnight. The plasma epinephrine and norepinephrine levels at 06:00 h were notably lower than those at 18:00 h in HPs (P = 0.004 and 0.01, respectively). Only NSs showed a significant reduction in the baPWV with a decrease in the plasma catecholamine levels in the morning, suggesting that the baPWV of NSs may be correlated with the variation of the plasma catecholamine levels.

It has not been fully examined whether angiotensin II receptor blocker is superior to calcium channel blocker to reduce cardiovascular events in hypertensive patients with glucose intolerance. A prospective, open-labeled, randomized, controlled trial was conducted for Japanese hypertensive patients with type 2 diabetes mellitus or impaired glucose tolerance. A total of 1150 patients (women: 34%; mean age: 63 years; diabetes mellitus: 82%) were randomly assigned to receive either valsartan- or amlodipine-based antihypertensive treatment. Primary outcome was a composite of acute myocardial infarction, stroke, coronary revascularization, admission attributed to heart failure, or sudden cardiac death. Blood pressure was 145/82 and 144/81 mm Hg, and glycosylated hemoglobin was 7.0% and 6.9% at baseline in the valsartan group and the amlodipine group, respectively. Both of them were equally controlled between the 2 groups during the study. The median follow-up period was 3.2 years, and primary outcome had occurred in 54 patients in the valsartan group and 56 in the amlodipine group (hazard ratio: 0.97 [95% CI: 0.66-1.40]; P=0.85). Patients in the valsartan group had a significantly lower incidence of heart failure than in the amlodipine group (hazard ratio: 0.20 [95% CI: 0.06-0.69]; P=0.01). Other components and all-cause mortality were not significantly different between the 2 groups. Composite cardiovascular outcomes were comparable between the valsartan- and amlodipine-based treatments in Japanese hypertensive patients with glucose intolerance. Admission because of heart failure was significantly less in the valsartan group.

Although recent clinical trials have found an increased incidence of cardiovascular disease in women on estrogen replacement therapy, the underlying mechanism remains unclear. We have recently characterized DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of metabolic syndrome. We have now examined the effects of estrogen replacement on cardiac pathophysiology in ovariectomized female DS/obese (Ovx-DS/obese) rats. Animals subjected to ovariectomy at 7 weeks of age were implanted subcutaneously with a 60-day release pellet containing 0.5 mg of 17β-estradiol (E(2)) or placebo at 8 weeks. Age-matched female homozygous lean littermates (DahlS.Z-Lepr(+)/Lepr(+) or DS/lean rats) of DS/obese rats served as controls. Animals were maintained on a normal diet and were subjected to echocardiography followed by various pathological analyses at 13 weeks of age. Ovx-DS/obese rats manifested hypertension at 7 weeks of age and thereafter and showed left ventricular (LV) fibrosis and diastolic dysfunction at 13 weeks. Treatment with E(2) attenuated hypertension in Ovx-DS/obese rats but had no effect on blood pressure in ovariectomized female DS/lean (Ovx-DS/lean) rats. E(2) treatment exacerbated LV fibrosis and diastolic dysfunction, as well as further increased cardiac oxidative stress and inflammation in Ovx-DS/obese rats, and it elicited similar effects in Ovx-DS/lean rats. E(2) reduced food intake, body weight, and visceral fat content in both Ovx-DS/obese and Ovx-DS/lean rats. E(2) treatment attenuated hypertension and obesity but exacerbated LV fibrosis and diastolic dysfunction in Ovx-DS/obese rats, with these latter effects being associated with increased cardiac oxidative stress and inflammation.

Background: The guidelines recommend combination therapy for patients who are unable to achieve target BP with monotherapy; some fixed dose therapies including an angiotensin II receptor blocker (ARB) and diuretics are available in Japan. However, to date there have been few reports on this long-term treatment and the patient profiles suited for this combination remain ambiguous., Method: The Aichi Research on Combination therapy for Hypertension Study was a multicenter, open-label, prospective observational study that investigated the efficacy and safety of 1-year treatment with the losartan-hydrochlorothiazide (HCTZ) combination tablet in patients with hypertension uncontrolled by either ARB monotherapy or combination therapy with a calcium channel blocker (CCB). An ARB was switched to a losartan-HCTZ tablet after a pre-observation period., Results: A total of 614 of 648 patients were evaluable (mean age, 66.3 years; 52.8% men; mean baseline blood pressure, BP, 157.7/87.9 mmHg). The BP had decreased significantly to 138.0/78.2 mmHg by month 3 (p<0.001, t-test), and 36.2% of the patients had achieved their target BP. The hypotensive effect lasted for 1 year and was found equally in the losartan-HCTZ arm and the losartan-HCTZ plus CCB arm. A stratified analysis showed significant hypotensive effects in patients with higher baseline BP, women, and patients who did not drink alcohol (p<0.001, unpaired t-test)., Conclusion: The losartan-HCTZ combination tablet was found to have an early hypotensive effect, good tolerability, and stable long-term benefits in patients with hypertension uncontrolled by ARB monotherapy or combination therapy with a CCB.

Background: The biologic response to angiotensin-converting enzyme (ACE) inhibitors may be influenced by the local environment. The effect of ACE inhibition on coronary angiogenesis was investigated in a rat model of hypertensive heart failure., Methods and Results: Dahl salt-sensitive (DS) rats fed a high-salt diet from 6 weeks of age were treated with a nonantihypertensive dose of the ACE inhibitor perindopril or vehicle from 9 to 18 weeks. Treatment of rats with perindopril attenuated the heart failure as well as cardiac hypertrophy and fibrosis that were manifest in the vehicle-treated animals. Myocardial capillary density as well as the expression of the bradykinin B(2) receptor, endothelial nitric oxide synthase, and vascular endothelial growth factor were reduced in the heart of vehicle-treated rats compared with that of nonhypertensive control rats, and all of these changes were attenuated by treatment with perindopril., Conclusions: These results indicate that ACE inhibition by perindopril promotes myocardial capillary formation as well as attenuates cardiac remodeling and failure in a manner independent from the antihypertensive effect of the drug in DS hypertensive rats. The beneficial cardiac effects of perindopril were associated with activation of the bradykinin-nitric oxide pathway in the heart., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Although thiazide diuretics are commonly used to supplement angiotensin receptor blockers for treatment of hypertension, the mechanism underlying the therapeutic effects of this drug combination remains unclear. We investigated the antihypertensive and cardioprotective effects of combination therapy with losartan (LOS) and hydrochlorothiazide (HCTZ), in comparison with those of either drug alone, in Dahl salt-sensitive hypertensive rats. Rats fed a high-salt diet from 6 weeks of age were treated with LOS, HCTZ, both drugs (COMB) and vehicle from 6 to 11 weeks. The salt-induced increase in systolic blood pressure was attenuated moderately by LOS and to a greater extent by HCTZ and COMB. Left ventricular (LV) hypertrophy and fibrosis, diastolic dysfunction, as well as angiotensin-converting enzyme and angiotensin II type 1A (AT(1A)) receptor gene expression were attenuated similarly by LOS and HCTZ and more so by COMB. LOS downregulated expression of the AT(1A) receptor gene, without affecting that of the AT(2) receptor gene, in the aorta. In contrast, neither HCTZ nor COMB affected aortic expression of the AT(1A) receptor gene, but both markedly upregulated that of the AT(2) receptor gene. The salt-induced decrease in the plasma concentration of nitric oxide metabolites was attenuated substantially by LOS and abolished by both HCTZ and COMB. In conclusion, the combination of LOS and HCTZ attenuated hypertension, as well as LV remodeling and diastolic dysfunction, more effectively than did LOS or HCTZ alone in rats with salt-sensitive hypertension. Modulation of the cardiac and vascular renin-angiotensin system may have contributed to these beneficial effects of the drug combination.

Background: The beneficial cardiac effects of some Ca(2+) channel blockers have been attributed to blood pressure reduction, but these pleiotropic effects require further investigation. We compared the effects of benidipine, which has beneficial cardiac effects, and nitrendipine, which does not, in an animal model of hypertensive diastolic heart failure (DHF)., Methods and Results: Male Dahl salt-sensitive rats were fed a high-salt diet from age 7 weeks to induce hypertension and were either vehicle or orally administered benidipine (3 mg/kg daily) or nitrendipine (10 mg/kg daily) from age 10 to 18 weeks. Control rats were maintained on a low-salt diet. In vehicle-treated rats, left-ventricular (LV) fractional shortening was preserved but LV end-diastolic pressure was increased, indicative of DHF. Benidipine and nitrendipine had similar antihypertensive effects and reduced both LV weight and cardiomyocyte hypertrophy. Benidipine reduced LV diastolic stiffness and mortality to a greater extent than did nitrendipine. Benidipine, but not nitrendipine, also reduced lung weight. The extent of interstitial fibrosis and the abundance of mRNAs for prohypertrophic, profibrotic, or proinflammatory genes in the left ventricle were reduced by benidipine and nitrendipine. Benidipine, but not nitrendipine, increased capillary density and restored the expression of hypoxia-inducible factor 1alpha, vascular endothelial growth factor, and endothelial nitric oxide synthase in the left ventricle., Conclusions: Benidipine reduced LV diastolic stiffness and increased survival, effects likely attributable predominantly to promotion of coronary angiogenesis rather than to attenuation of interstitial fibrosis. Benidipine may thus be more effective than purely L-type Ca(2+) channel blockers in preventing hypertensive DHF.

Background: Inhibitors of the renin angiotensin system are recommended as the first-line medications for diabetic hypertensive patients. However, there is less evidence supporting this recommendation especially among East Asians, a population with a unique distribution of cardiovascular disease compared to the Western population., Methods and Results: The NAGOYA HEART Study is a prospective randomized open-label blinded-endpoint study to compare an angiotensin II receptor blocker, valsartan, and a calcium channel blocker, amlodipine, regarding their efficacies on cardiovascular morbidity and mortality in Japanese hypertensive patients with glucose intolerance. Of 1168 eligible patients, we enrolled 1150 patients from October 2004 to January 2009. The participants will be followed for more than a median follow-up period of 3 years. The primary composite endpoint includes myocardial infarction, stroke, coronary revascularization, and admission due to congestive heart failure or sudden cardiac death. Any of these events are adjudicated by an independent committee under blinded information regarding the treatment arm. Secondary endpoints include all-cause mortality, changes in glucose tolerance status, kidney function, left ventricular structure measured by echocardiogram, and incident atrial fibrillation/flutter. The study was registered at ClinicalTrials.gov NCT00129233., Conclusion: The NAGOYA HEART Study will provide us with a relevant insight for appropriate treatment of hypertension with glucose intolerance., (Copyright 2010 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: Asymmetrical septal hypertrophy and impaired left ventricular (LV) diastolic function are common echocardiographic features of hypertrophic cardiomyopathy (HCM). However, it is difficult to differentiate nonobstructive HCM from hypertensive LV hypertrophy (H-LVH)., Methods and Results: Standard echocardiography and tissue Doppler imaging were performed in 14 patients with HCM, 16 patients with H-LVH, and 21 control subjects. Endomyocardial radial strain, systolic strain rate (SR), and the early diastolic SR at the posterior and septal segments of the LV short axis were calculated. Endomyocardial peak strain (epsilon) and the absolute value of peak early diastolic SR at the posterior segment were significantly smaller in patients with HCM than in those with H-LVH, whereas the thickness of the LV posterior wall did not differ between these 2 groups. Multivariate analysis of discrimination, including the ratio of interventricular septal thickness and posterior wall thickness (IVST/PWT), epsilon, and SR parameters, between HCM and H-LVH patients revealed that epsilon at the LV posterior segment was the highest discriminant parameter (discriminant coefficient: -14.6, P=0.012). The epsilon at the posterior segment significantly correlated with early diastolic mitral annular velocity., Conclusions: Endomyocardial radial strain imaging may prove informative for discriminating between HCM and H-LVH.

The Ca2+ channel blocker nifedipine has been reported to reduce the rate of new overt heart failure. We investigated the effects of nifedipine on left ventricular remodeling, oxidative stress, and gene expression in the failing heart of Dahl salt-sensitive (DS) rats. DS rats fed a high-salt diet from 7 weeks of age were treated with a non-antihypertensive (1 mg/kg per day, Nif-L) or mild-antihypertensive dose of nifedipine (3 mg/kg per day, Nif-H) or with vehicle (Vehicle) from 12 to 19 weeks. Marked left ventricular hypertrophy and fibrosis were apparent and the ratio of collagen type I to type III mRNA levels and the activity of matrix metalloproteinase (MMP)-2 and its mRNA expression in the myocardium were increased in Vehicle at 19 weeks in comparison with Control. Load-induced left ventricular hypertrophy was reduced in Nif-H, but not in Nif-L, relative to that in Vehicle. Treatment with either dose of nifedipine reduced the extent of fibrosis, the collagen type I to type III mRNA ratio, and MMP-2 activity and its mRNA expression compared with those in Vehicle. The decrease in the ratio of reduced to oxidized glutathione and the increase in NADPH oxidase activity apparent in the left ventricle of Vehicle were also inhibited by nifedipine at both doses. Nifedipine thus inhibited the development of left ventricular fibrosis and diastolic heart failure in DS rats, independently of its antihypertensive effect. The overall protective action of nifedipine is likely attributable to its antioxidant effect as well as to its antihypertensive action.

The clinical efficacy of exercise training in individuals with heart failure is well established, but the mechanism underlying such efficacy has remained unclear. An imbalance between cardiac hypertrophy and angiogenesis is implicated in the transition to heart failure. We investigated the effects of exercise training on cardiac pathophysiology in hypertensive rats. Dahl salt-sensitive rats fed a high-salt diet from 6 weeks of age were assigned to sedentary or exercise (swimming)-trained groups at 9 weeks. Exercise training attenuated the development of heart failure and increased survival, without affecting blood pressure, at 18 weeks. It also attenuated left ventricular concentricity without a reduction in left ventricular mass or impairment of cardiac function. Interstitial fibrosis was increased and myocardial capillary density was decreased in the heart of sedentary rats, and these effects were attenuated by exercise. Exercise potentiated increases in the phosphorylation of Akt and mammalian target of rapamycin observed in the heart of sedentary rats, whereas it inhibited the downregulation of proangiogenic gene expression apparent in these animals. The abundance of the p110alpha isoform of phosphatidylinositol 3-kinase was decreased, whereas those of the p110gamma isoform of phosphatidylinositol 3-kinase and the phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase were increased, in the heart of sedentary rats, and all of these effects were prevented by exercise. Thus, exercise training had a beneficial effect on cardiac remodeling and attenuated heart failure in hypertensive rats, with these effects likely being attributable to the attenuation of left ventricular concentricity and restoration of coronary angiogenesis through activation of phosphatidylinositol 3-kinase(p110alpha)-Akt-mammalian target of rapamycin signaling.

The renin-angiotensin system (RAS) plays an important role in the maintenance of normal blood pressure and the etiology of hypertension; however, minimal attention has been paid to the degradation of the effector peptide, angiotensin II (AngII). Since aminopeptidase A (APA)-deficient mice develop hypertension APA appears to be an essential enzyme in the control of blood pressure via degradation of AngII. The robust hypertension seen in the spontaneously hypertensive rat (SHR) is due to activation of the RAS, and an accompanying decrease in kidney APA. Changes in APA have also been measured during the activation of the RAS in the Goldblatt hypertension model and Dahl salt-sensitive (DSS) rat. The DSS rat shows an elevation in renal APA activity at the onset of hypertension suggesting a protective role against elevations in circulating AngII, followed by decreased APA activity with advancing hypertension. Changes seen in human maternal serum APA activity during preeclampsia are similar to changes measured in renal APA in the DSS rat model. APA activity is higher than during normal pregnancy at the onset of preeclampsia, and with advancing preeclampsia (severe preeclampsia) declines below that seen during normal pregnancy. Serum APA activity is also increased during hormone replacement therapy (HRT), perhaps in reaction to elevated levels of AngII. Thus, it appears important to consider the relationship among activation of the RAS, circulating levels of AngII, and the availability of APA in hypertensive disorders.

Background: Conventional risk factors for thoracic aortic aneurysm including dissection (TAA) are thought to include age, arteriosclerosis, and hypertension. In addition, evidence suggests that genetic factors play a role in the development of this condition. The purpose of the present study was to identify genetic variants that confer susceptibility to TAA in hypertensive subjects., Methods: Study subjects comprised 1,351 hypertensive individuals: 88 patients with TAA and 1,263 subjects without this condition. The genotypes for 142 polymorphisms of 119 candidate genes were determined by a method that combines the PCR and sequence-specific oligonucleotide probes with suspension array technology., Results: Evaluation of genotype distributions by the chi2-test and subsequent multivariable logistic regression analysis with adjustment for covariates revealed that the 3949T-->G (3' untranslated region) polymorphism of the thrombospondin-2 gene (THBS2; odds ratio, 4.6), the -110A-->C polymorphism of the heat shock 70-kDa protein 8 gene (HSPA8; odds ratio, 0.4), the C-->T (Pro198Leu) polymorphism of the glutathione peroxidase 1 gene (GPX1; odds ratio, 0.3), the -6G-->A polymorphism of the angiotensinogen gene (AGT; odds ratio, 0.3), and the -850C-->T polymorphism of the tumor necrosis factor gene (TNF; odds ratio, 0.5) were significantly (P < 0.05) associated with TAA., Conclusions: The variant allele of THBS2 is a risk factor for TAA in hypertensive patients, whereas the variant alleles of HSPA8, GPX1, AGT, and TNF are protective against this condition. Determination of genotypes for these polymorphisms may prove informative for assessment of the genetic risk for TAA.

Nifedipine has been shown to improve endothelial function. Recent studies have indicated that endothelial function is correlated with the number of circulating endothelial progenitor cells (EPCs), but it is unclear whether nifedipine affects the number and function of EPCs. The aims of this study were to determine the effects of nifedipine on the number and function of EPCs and to investigate the relationship between improvement of endothelial function and EPC numbers in patients with hypertension. Stage 1 hypertensive men (n=37) were randomly divided into the nifedipine group and the control untreated group. The nifedipine group was administered slow-release nifedipine (20 mg) once daily. At baseline and after 4 weeks, flow-mediated dilation, blood pressure, biochemical data, and number of circulating CD34+CD133+ progenitor cells and EPCs were measured. The direct effects of nifedipine on EPC number and function were assessed in vitro. In the nifedipine group, flow-mediated dilation and the numbers of circulating CD34+CD133+ progenitor cells and EPCs were increased, along with a decrease of serum malondialdehyde low-density lipoprotein. The improvement of flow-mediated dilation by nifedipine was correlated with the increase of circulating CD34+CD133+ progenitor cells. Nifedipine also improved angiogenesis-related functions of EPCs (differentiation, migration, and resistance to oxidative stress) in vitro. Thus, nifedipine improved endothelial function and EPC function in stage 1 hypertensive subjects. The latter action may be mediated by reduction of oxidative stress and suppression of EPC apoptosis. These results demonstrate that nifedipine preserves endothelial integrity in patients with hypertension, at least partly, by enhancing EPC numbers and activity.

Objective: Cardiac hypertrophy is common in diabetes and an independent risk factor for cardiac morbidity and mortality. We investigated the effects of pioglitazone on cardiac hypertrophy and hypertrophic signaling in Dahl salt-sensitive hypertensive rats., Methods: Dahl salt-sensitive rats were fed a high-salt diet from 7 weeks of age and treated with pioglitazone (2.5 mg/kg per day) or vehicle from 7 to 11 weeks., Results: The vehicle-treated rats developed left ventricular hypertrophy and fibrosis as well as left ventricular diastolic dysfunction. The serum level of adiponectin and the phosphorylation of AMP-activated protein kinase in the myocardium did not differ between the vehicle-treated rats and control rats maintained on a normal diet. The phosphorylation of Akt, mammalian target of rapamycin, and p70S6 kinase as well as the total protein content were increased in the heart of vehicle-treated rats compared with control rats, and these changes were blocked by treatment with pioglitazone. Pioglitazone treatment also ameliorated left ventricular hypertrophy and fibrosis, improved diastolic function, and increased both the serum adiponectin concentration and the level of AMP-activated protein kinase phosphorylation in the heart., Conclusions: Long-term administration of pioglitazone attenuated left ventricular hypertrophy and fibrosis as well as inhibited phosphorylation of mammalian target of rapamycin and p70S6 kinase in the heart of hypertensive rats. The beneficial cardiac effects of pioglitazone are likely attributable, at least partly, both to the activation of AMP-activated protein kinase signaling through stimulation of adiponectin secretion and to the inhibition of Akt signaling.

Primary systemic carnitine deficiency is an autosomal recessive disorder caused by a decreased renal reabsorption of carnitine because of mutations of the carnitine transporter OCTN2 gene, and hypertrophic cardiomyopathy is a common clinical feature of homozygotes. Although heterozygotes for OCTN2 mutations are generally healthy with normal cardiac performance, heterozygotes may be at risk for cardiomyopathy in the presence of additional risk factors, such as hypertension. To test this hypothesis, we investigated the effects of surgically induced pressure overload on the hearts of heterozygous mutants of a murine model of OCTN2 mutation, juvenile visceral steatosis mouse (jvs/+). Eleven-week-old jvs/+ mice and age-matched wild-type mice were used. At baseline, there were no differences in physical characteristics between wild-type and jvs/+ mice. However, plasma and myocardial total carnitine levels in jvs/+ mice were lower than in wild-type mice. Both wild-type and jvs/+ mice were subjected to ascending aortic constriction with or without 1% l-carnitine supplementation for 4 weeks. At 4 weeks after ascending aortic constriction, jvs/+ mice showed an exaggeration of cardiac hypertrophy and pulmonary congestion, further increased gene expression of atrial natriuretic peptide in the left ventricles, further deterioration of left ventricular fractional shortening, reduced myocardial phosphocreatine:adenosine triphosphate ratio, and increased mortality compared with wild-type mice; l-carnitine supplementation prevented these changes in jvs/+ mice subjected to ascending aortic constriction. In conclusion, cardiomyopathy and heart failure with energy depletion may be induced by pressure overload in heterozygotes for OCTN2 mutations and could be prevented by l-carnitine supplementation.

Cathepsins are cysteine proteases that participate in various types of tissue remodeling. However, their expressions during myocardial remodeling have not been examined. In this study, we investigated their expressions in the left ventricular (LV) myocardium of rats and humans with hypertension-induced LV hypertrophy or heart failure (HF). Real-time PCR and immunoblot analysis revealed that the abundance of cathepsin S mRNA or protein in the LV tissues was greater in rats or humans with HF than in those with hypertrophy or in control subjects. Immunostaining showed that cathepsin S was localized predominantly to cardiac myocytes and coronary vascular smooth muscle cells, but also overlapped in part with macrophages. Elastic lamina fragmentations significantly increased in the LV intramyocardial coronary arteries of HF rats. The amount of elastolytic activity in the extract of the LV myocardium was markedly increased for HF rats compared with controls, and this activity was mostly because of cathepsin S. Although the amount of elastin mRNA was increased in the LV myocardium of HF rats, the area of interstitial elastin was not. The expression of interleukin 1beta was increased in the LV myocardium of HF rats, and this cytokine was found to increase the expression and activity of cathepsin S in cultured neonatal cardiomyocytes. These results suggest that cathepsin S participates in pathological LV remodeling associated with hypertension-induced HF. This protease is, thus, a potential target for therapeutics aimed at preventing or reversing cardiac remodeling.

It is known that renal nitric oxide (NO) is an important controller of urinary sodium excretion. A defect in the kidney's NO system could cause salt-sensitive hypertension. Since it has been demonstrated that doxorubicin binds to the reductase domain of endothelial NO synthase (eNOS) and generates superoxide in vitro, we tested our hypothesis that a high-sodium diet would upregulate the expression of eNOS and enhance oxidative stress in the kidney of doxorubicin-treated rats, resulting in a facilitation of hypertension. At 4 weeks after treatment with doxorubicin in Sprague-Dawley rats, the systolic blood pressure significantly increased only in the high-sodium diet group. The expressions of eNOS protein in the renal cortex and medulla were significantly higher in high-sodium groups than in normal-sodium groups, regardless of doxorubicin treatment. In rats treated with doxorubicin, a biomarker of oxidative damage 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunohistological staining of renal tissues showed strong staining of the proximal and distal tubules. In particular, rats with doxorubicin in the high-sodium diet group demonstrated a significant increase in urinary exertion of 8-OHdG as well as more prominently stained tubules against 8-OHdG antibody, but markedly lower urinary NO(x) excretion than in rats without doxorubicin, even than in the untreated, low-sodium group. In conclusion, these results indicate that the oxidative stress induced by doxorubicin impairs NO production in the kidney. As such, doxorubicin treatment appears to contribute to the development of salt-sensitive hypertension through reductive activation of upregulated eNOS by a high-sodium diet instead of NO production.

Chronic elevation of plasma aldosterone contributes to heart failure. Mineralocorticoid receptor (MR) antagonism is cardioprotective in such a setting, but whether such protection occurs in the presence of low-aldosterone concentrations remains unclear. We investigated whether MR blockade attenuates cardiac hypertrophy and failure in rats with salt-sensitive hypertension. Dahl salt-sensitive (DS) rats fed a high-salt diet from 7 weeks develop concentric left ventricular (LV) hypertrophy secondary to hypertension at 12 weeks followed by heart failure at 19 weeks (DS-CHF). DS rats on such a diet were treated with a non-antihypertensive dose of the selective MR antagonist eplerenone from 12 to 19 weeks. Renin activity and aldosterone concentration in plasma were decreased in DS-CHF rats compared with controls. LV hypertrophy and fibrosis, as well as macrophage infiltration around coronary vessels, were apparent in DS-CHF rats. The amounts of mRNAs for 11beta-hydroxysteroid dehydrogenase type 1, MR, monocyte chemoattractant protein 1, and osteopontin were increased in these hearts. Treatment of DS-CHF rats with eplerenone inhibited these changes in gene expression, as well as coronary vascular inflammation and heart failure. Eplerenone attenuated both the decrease in the ratio of reduced to oxidized glutathione and the increase in NADPH oxidase activity apparent in DS-CHF rat hearts. MR blockade with eplerenone thus resulted in attenuation of LV hypertrophy and failure, without an antihypertensive effect, in rats with low-aldosterone hypertension. The beneficial cardiac effects of eplerenone are likely attributable, at least in part, to attenuation of myocardial oxidative stress and coronary vascular inflammation induced by glucocorticoid-activated MRs.

Long-term administration of vasodilators increases shear stress, which is thought to be important for vascular growth in the heart. Nicorandil, an activator of ATP-sensitive potassium channels with a nitrate-like action, is a potent vasodilator. We have now investigated the effects of nicorandil on vascular growth and gene expression in the failing heart of Dahl salt-sensitive (DS) hypertensive rats. DS rats fed a high-salt diet from 6 weeks of age develop concentric cardiac hypertrophy secondary to hypertension at 11 weeks, followed by heart failure at 18 weeks. DS rats on such a diet were treated with a nonantihypertensive oral dose of nicorandil (6 mg/kg per day) or vehicle from 11 to 18 weeks of age. Treatment of DS rats with nicorandil improved cardiac function and attenuated the development of heart failure. Myocardial capillary and arteriolar densities did not differ between vehicle-treated DS rats and age-matched controls. The abundance of mRNAs for endothelial NO synthase (eNOS), vascular endothelial growth factor (VEGF), the VEGF receptor Flt-1, and basic fibroblast growth factor (bFGF) in the myocardium was markedly reduced in vehicle-treated DS rats compared with controls. Treatment of DS rats with nicorandil greatly increased capillary and arteriolar densities and inhibited the downregulation of eNOS, VEGF, fms-like tyrosin kinase-1, and bFGF gene expression. This, nicorandil stimulates coronary capillary and arteriolar growth and thereby likely suppresses the development of heart failure in DS rats. Nicorandil may prove beneficial for the treatment of hypertensive heart failure as well as of ischemic heart disease.

The spontaneously hypertensive rat (SHR) has been well established as a suitable model for studies of hypertension, but little is known about the processes of left ventricular (LV) hypertrophy and the changes in cardiac function in this model. The present study was designed to provide a noninvasive evaluation of the time-dependent alteration of cardiac function in male SHR at 4 to 24 weeks of age and age-matched Wistar-Kyoto rats (WKY). Echocardiographic studies were performed after blood pressure (BP) and heart rate (HR) were measured by a tail-cuff method. The body weight (BW) of SHR was lighter than that of WKY at all ages, and HR was consistently lower, with significantly elevated systolic BP from 4 weeks of age. In the echocardiographic study, LV mass at 4 weeks of age was similar between WKY and SHR, although the ratio of LV mass to BW was higher in SHR than WKY. The ejection fraction, fractional shortening (FS) and midwall FS did not differ between the two groups at 4 weeks, but after 8 weeks, these parameters were decreased in the SHR. The deceleration time was prolonged in SHR after 16 weeks and the E/A ratio was lowered at 12 weeks. We also analyzed the expression levels of calcineurin, which were found to be increased in both groups with age. These results suggest that calcineurin does not play a major role in the development of LV hypertrophy. Thus, in SHR, cardiac hypertrophy develops by 4 weeks of age, and systolic and diastolic dysfunction is evident at 2 to 3 months.

Background: The differentiation of hypertrophic cardiomyopathy (HCM) from hypertensive left ventricular hypertrophy (H-LVH) on the basis of morphological information obtained by conventional echocardiography is occasionally problematic. We investigated whether strain rate (SR) imaging derived from tissue Doppler imaging (TDI) is able to discriminate HCM from H-LVH., Methods and Results: Conventional echocardiography and TDI were performed with 34 patients with LVH and 16 reference subjects. Mean values of systolic strain (epsilon(sys)), peak systolic SR, and early diastolic SR obtained from 8 left ventricular (LV) segments were calculated. LV pressures were recorded simultaneously in the patients. Patients were diagnosed with HCM (n=20) or H-LVH (n=14) on the basis of conventional echocardiography and endomyocardial biopsy findings. Multivariate analysis revealed that septum/posterior wall thickness ratio (P=0.00013) and epsilon(sys) (P<0.0001) were each able to discriminate HCM from H-LVH. A epsilon(sys) cutoff value of -10.6% discriminated between HCM and H-LVH with a sensitivity of 85.0%, specificity of 100.0%, and predictive accuracy of 91.2%. The combination of the septum/posterior wall thickness ratio and epsilon(sys) discriminated HCM from H-LVH with a predictive accuracy of 96.1%. The epsilon(sys) parameter was significantly correlated with pulmonary arterial wedge pressure, LV end-diastolic pressure, the peak positive first derivative of LV pressure, and the time constant of LV pressure decay., Conclusions: SR imaging is able to discriminate HCM from H-LVH, with epsilon(sys) reflecting myocardial contractile and lusitropic properties.

Background: Although genetic epidemiological studies have suggested that several genetic variants increase the risk for hypertension, the genes that underlie genetic susceptibility to this condition remain to be identified definitively. Large-scale association studies that examine many gene polymorphisms simultaneously are required to predict genetic risk for hypertension., Methods and Results: The population of the present study comprised 1,940 unrelated Japanese individuals, including 1,067 subjects with hypertension (574 men, 493 women) and 873 controls (533 men, 340 women). The genotypes for 33 single nucleotide polymorphisms of 27 candidate genes were determined with a fluorescence- or colorimetry-based allele-specific DNA primer-probe assay system. Multivariate logistic regression analysis with adjustment for age, body mass index, and the prevalence of smoking, diabetes mellitus, hypercholesterolemia, and hyperuricemia revealed that two polymorphisms (825C -> T in the G protein beta3 subunit gene and 190G -> A in the CC chemokine receptor 2 gene) were significantly associated with hypertension in men and that one polymorphism (-238G -> A in the tumor necrosis factor- alpha gene) was significantly associated with hypertension in women., Conclusion: These results suggest that two and one genes may be susceptibility loci for hypertension in Japanese men and women, respectively, and that genotyping of these polymorphisms may prove informative for prediction of the genetic risk for hypertension.

There is a relationship between mental and physical health. Depression and anxiety are linked with the development of several chronic diseases. The purpose of the present study was to determine the prevalence and factors associated with anxiety and depression among adult hypertensive outpatients in Afghanistan. Methods. Two hundred thirty-four consecutive hypertensive patients from December 2015 to August 2016 were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire, which has scores for classifying the participants having anxiety and depression symptoms. Results. Of the total 234 patients, 81 (34.6%) were males and 153 (65.4%) were females. The mean age was 54.6±12.7 for the hypertensive patients with anxiety and 63.8±15.0 for the hypertensive patients with depression while this figure was 49.5±10.2 for the adult participants in general population in Kabul city (Saeed, 2013). The prevalence of anxiety and depression (42.3% vs. 58.1%) among hypertensive persons is compared with the same mental disorders among Afghan refugees (39.3% vs. 22.1%) in Dalakee Refugee Camp (in Iran) (Hosseini Divkolaye and Burkle, 2017). Of the total participants, 99 had anxiety (42.3%), 136 had depression (58.1%), and 66 had (28.2%) comorbid anxiety-depression. Multivariate analysis was used. For anxiety age, female gender, smoking, diabetes mellitus, and 2 or more chronic diseases had a significant association. For depression, age and diabetes mellitus had a significant association, and for comorbid anxiety, depression, age, diabetes mellitus, and 2 or more chronic diseases had a significant association. Conclusion. This study shows that anxiety and depression are highly prevalent among hypertensive patients in an outpatient clinic in Afghanistan. There was an association between some sociodemographic and clinical characteristics and anxiety and depression. More studies are needed on a national level to inform the development of strategies for the prevention and control of psychological distress among patients with chronic diseases in Afghanistan. [ABSTRACT FROM AUTHOR]

Background Although several prognostic factors of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) have been investigated, the accurate prediction of AF recurrence remains difficult. We propose an electrocardiogram (ECG) index, the P-wave force (PWF), which is the product of the amplitude of the negative terminal phase of the P wave in the V1 electrode and the filtered P-wave duration, obtained by a signal-averaged P-wave analysis. This study was conducted to evaluate the impact of the PWF on the recurrence of AF after PVI. Methods We retrospectively evaluated 79 paroxysmal AF patients (64 ± 9 years, 56 males) who underwent PVI by cryoballoon ablation. Standard 12-lead ECG and a P-wave signal-averaged electrocardiogram (SAECG) were recorded the day before and 1 month after the PVI procedure. Results During the mean follow-up of 10.2 months, AF recurred in 11 (14%) patients. The PWF 1 month after ablation was significantly higher in the recurrence group compared to that in the nonrecurrence group (8.8 ± 3.1 mVms vs 6.5 ± 2.9 mVms, P = 0.017). The patients with a PWF value ≥9.3 mVms had a significantly greater risk of recurrence after the ablation compared to the patients with a PWF value <9.3 mVms (log-rank test, P < 0.001). Conclusion Higher PWF after cryoballoon ablation was associated with poor prognosis during follow-up. The PWF may be a useful and noninvasive marker to predict the recurrence of AF. [ABSTRACT FROM AUTHOR]