Sparing and enhancing dose protraction effects for radiation damage to the aorta of wild-type mice.

PURPOSE: Our previous work indicated the greater magnitude of damage to the thoracic aorta at 6 months after starting 5 Gy irradiation in descending order of exposure to X-rays in 25 fractions > acute X-rays > acute γ-rays > X-rays in 100 fractions ≫ chronic γ-rays, in which the limitations of the study included a lack of data for fractionated γ-ray exposure. To better understand effects of dose protraction and radiation quality, the present study examined changes after exposure to γ-rays in 25 fractions, and compared its biological effectiveness with five other irradiation regimens. MATERIALS AND METHODS: Male C57BL/6J mice received 5 Gy of 137Cs γ-rays delivered in 25 fractions spread over six weeks. At 6 months after starting irradiation, mice were subjected to echocardiography, followed by tissue sampling. The descending thoracic aorta underwent scanning electron microscopy, immunofluorescence staining and histochemical staining. The integrative analysis of multiple aortic endpoints was conducted for inter-regimen comparisons. RESULTS: Exposure to γ-rays in 25 fractions induced vascular damage (evidenced by increases in endothelial detachment and vascular endothelial cell death, decreases in endothelial waviness, CD31, endothelial nitric oxide synthase and vascular endothelial cadherin), inflammation (evidenced by increases in tumor necrosis factor α, CD68 and F4/80) and fibrosis (evidenced by increases in transforming growth factor ß1, alanine blue stain and intima-media thickness). The integrative analysis revealed biological effectiveness in descending order of exposure to X-rays in 25 fractions > acute X-rays > γ-rays in 25 fractions > acute γ-rays > X-rays in 100 fractions ≫ chronic γ-rays. CONCLUSIONS: The results suggest that dose protraction effects on aortic damage depend on radiation quality, and are not a simple function of dose rate and the number of fractions.

Impact of overnight 1 mg dexamethasone on vascular function in patients with nonfunctioning adrenal adenomas.

The purpose of this study was to evaluate the effects of administration of overnight 1 mg dexamethasone on vascular function in patients with nonfunctioning adrenal adenomas (NFA). Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) were measured to assess vascular function in 22 patients with NFA who had hypertension and/or diabetes mellitus (DM) and 272 patients without adrenal incidentalomas who had hypertension and/or DM (control patients with hypertension and/or DM). FMD and NID were measured in the morning before and after administration of 1 mg of dexamethasone at 2300 h in 18 patients with NFA. There were no significant differences in FMD and NID between control patients with hypertension and/or DM and patients with NFA who had hypertension and/or DM (3.4 ± 2.8% vs. 2.9 ± 1.9% and 11.5 ± 5.7% vs. 11.4 ± 4.3%, P = 0.46, and P = 0.99, respectively). There were no significant differences in vascular function between control patients with hypertension and/or DM and patients with NFA who had hypertension and/or DM even after adjustment for cardiovascular risk factors. Overnight 1 mg dexamethasone increased FMD from 2.4 ± 1.9% to 5.3 ± 3.2% (P < 0.01) and increased NID from 12.1 ± 4.2% to 14.0 ± 2.8% (P < 0.01) in patients with NFA. The overnight 1 mg dexamethasone suppression test does not impair FMD and NID in patients with NFA. Decreases in circulating levels of cortisol may improve vascular function.Clinical Trial Registration: This study was approved by principal authorities and ethical issues in Japan (URL for Clinical Trial: http://www.umin.ac.jp/ctr/index.htm Registration Number for Clinical Trial: UMIN000039512).

KCNJ5 mutation is a predictor for recovery of endothelial function after adrenalectomy in patients with aldosterone-producing adenoma.

The relationship of KCNJ5 mutation with vascular function and vascular structure in aldosterone-producing adenoma (APA) patients before and after adrenalectomy remains unclear. The purpose of this study was to evaluate the influence of KCNJ5 mutation on vascular function and vascular structure in APA and the effects of adrenalectomy on vascular function and vascular structure in APA patients with and those without KCNJ5 mutation. Flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID), brachial artery intima-media thickness (IMT), and brachial-ankle pulse wave velocity (baPWV) were measured to assess vascular function and vascular structure in 46 APA patients with KCNJ5 mutation and 23 APA patients without KCNJ5 mutation and in 69 matched pairs of patients with essential hypertension (EHT). FMD, NID, brachial IMT and baPVW were evacuated before adrenalectomy and at 12 weeks after adrenalectomy in APA patients with KCNJ5 mutation and APA patients without KCNJ5 mutation. FMD and NID were significantly lower in APA patients than in patients with EHT. There was no significant difference in FMD or NID between patients with and those without KCNJ5 mutation. In APA patients with KCNJ5 mutation, FMD and NID after adrenalectomy were significantly higher than those before adrenalectomy. In APA patients without KCNJ5 mutation, only NID after adrenalectomy was significantly higher than that before adrenalectomy. Endothelial function in APA patients with KCNJ5 mutation was improved by adrenalectomy in the early postoperative period. KCNJ5 mutation is a predictor for early resolution of endothelial function by adrenalectomy. This study was approved by principal authorities and ethical issues in Japan (URL for Clinical Trial: http://www.umin.ac.jp/ctr/index.htm Registration Number for Clinical Trial: UMIN000003409).

Endothelial Function Is Preserved in Patients with Wild-Type Transthyretin Amyloid Cardiomyopathy.

Heart failure (HF) is associated with endothelial dysfunction. Vascular function per se plays an important role in cardiac function, whether it is a cause or consequence. However, there is no information on vascular function in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). The purpose of this study was to evaluate vascular function in patients with ATTRwt-CM. We measured flow-mediated vasodilation (FMD) as an index of endothelial function and nitroglycerine-induced vasodilation (NID) as an index of vascular smooth muscle function and brachial artery intima-media thickness (bIMT) and brachial-ankle pulse wave velocity (baPWV) as indices of arterial stiffness in 22 patients with ATTRwt-CM and in 22 one-by-one matched control patients using vascular function confounding factors. FMD was significantly greater in patients with ATTRwt-CM than in the controls (5.4 ± 3.4% versus 3.5 ± 2.4%, p = 0.038) and the N-terminal pro-brain natriuretic peptide (NT-proBNP) level was significantly greater in patients with ATTRwt-CM than in the controls (2202 ± 1478 versus 470 ± 677 pg/mL, p < 0.001). There were no significant differences in NID, bIMT or baPWV between the two groups. There was a significant relationship between NT-proBNP and FMD in patients with ATTRwt-CM (r = 0.485, p = 0.022). NT-proBNP showed no significant relationships with NID, bIMT or baPWV. Conclusions: Endothelial function was preserved in patients with ATTRwt-CM. Patients with ATTRwt-CM may have compensatory effects with respect to endothelial function through elevation of BNP.

Effect of exposure to radiation caused by an atomic bomb on endothelial function in atomic bomb survivors.

Background: The purpose of this study was to evaluate the effects of exposure to radiation caused by an atomic bomb in atomic bomb survivors on vascular function and vascular structure and to evaluate the relationships of radiation dose from the atomic bomb with vascular function and vascular structure in atomic bomb survivors. Methods: Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) as indices of vascular function, brachial-ankle pulse wave velocity (baPWV) as an index of vascular function and vascular structure, and brachial artery intima-media thickness (IMT) as an index of vascular structure were measured in 131 atomic bomb survivors and 1,153 control subjects who were not exposed to the atomic bomb. Ten of the 131 atomic bomb survivors with estimated radiation dose in a cohort study of Atomic Bomb Survivors in Hiroshima were enrolled in the study to evaluate the relationships of radiation dose from the atomic bomb with vascular function and vascular structure. Results: There was no significant difference in FMD, NID, baPWV, or brachial artery IMT between control subjects and atomic bomb survivors. After adjustment of confounding factors, there was still no significant difference in FMD, NID, baPWV, or brachial artery IMT between control subjects and atomic bomb survivors. Radiation dose from the atomic bomb was negatively correlated with FMD (ρ = -0.73, P = 0.02), whereas radiation dose was not correlated with NID, baPWV or brachial artery IMT. Conclusion: There were no significant differences in vascular function and vascular structure between control subjects and atomic bomb survivors. Radiation dose from the atomic bomb might be negatively correlated with endothelial function.

Temporal Changes in Sparing and Enhancing Dose Protraction Effects of Ionizing Irradiation for Aortic Damage in Wild-Type Mice.

In medical and occupational settings, ionizing irradiation of the circulatory system occurs at various dose rates. We previously found sparing and enhancing dose protraction effects for aortic changes in wild-type mice at 6 months after starting irradiation with 5 Gy of photons. Here, we further analyzed changes at 12 months after stating irradiation. Irrespective of irradiation regimens, irradiation little affected left ventricular function, heart weight, and kidney weight. Irradiation caused structural disorganizations and intima-media thickening in the aorta, along with concurrent elevations of markers for proinflammation, macrophage, profibrosis, and fibrosis, and reductions in markers for vascular functionality and cell adhesion in the aortic endothelium. These changes were qualitatively similar but quantitatively less at 12 months than at 6 months. The magnitude of such changes at 12 months was not smaller in 25 fractions (Frs) but was smaller in 100 Frs and chronic exposure than acute exposure. The magnitude at 6 and 12 months was greater in 25 Frs, smaller in 100 Frs, and much smaller in chronic exposure than acute exposure. These findings suggest that dose protraction changes aortic damage, in a fashion that depends on post-irradiation time and is not a simple function of dose rate.

White blood cell count is not associated with flow-mediated vasodilation or nitroglycerine-induced vasodilation.

It is well known that white blood cell (WBC) count is an independent predictor of cardiovascular events. However, associations of WBC count and WBC subtypes with endothelial function assessed by flow-mediated vasodilation (FMD) and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation (NID) are unclear. The aim of this study was to determine the relationships of WBC count and WBC subtypes with vascular function assessed by FMD and NID. A total of 1351 subjects in whom FMD and NID had been measured were recruited from Hiroshima University Vascular Registry. Mean values were 3.7 ± 2.8% for FMD and 11.8 ± 5.9% for NID. WBC was not correlated with FMD or NID. NID was significantly correlated with lymphocytes in univariate analysis but not with other hematologic parameters. In multiple linear regression analyses, NID was not correlated with lymphocytes. In all subgroups including subgroups of age, gender, body mass index, hypertension, dyslipidemia, diabetes mellitus, smoking and tertile of WBC count, WBC count was not correlated with FMD or NID. WBC count and WBC subtypes were not associated with endothelial function assessed by FMD or vascular smooth muscle function assessed by NID. WBC count and vascular function assessed by FMD and NID may reflect different aspects of atherosclerosis.Clinical Trial Registration Information: URL for Clinical Trial: http://www.umin.ac.jp Registration Number for Clinical Trial: UMIN000039512.

Implantation of Hypoxia-Induced Mesenchymal Stem Cell Advances Therapeutic Angiogenesis.

Hypoxia preconditioning enhances the paracrine abilities of mesenchymal stem cells (MSCs) for vascular regeneration and tissue healing. Implantation of hypoxia-induced mesenchymal stem cells (hi-MSCs) may further improve limb perfusion in a murine model of hindlimb ischemia. This study is aimed at determining whether implantation of hi-MSCs is an effective modality for improving outcomes of treatment of ischemic artery diseases. We evaluated the effects of human bone marrow-derived MSC implantation on limb blood flow in an ischemic hindlimb model. hi-MSCs were prepared by cell culture under 1% oxygen for 24 hours prior to implantation. A total of 1 × 105 MSCs and hi-MSCs and phosphate-buffered saline (PBS) were intramuscularly implanted into ischemic muscles at 36 hours after surgery. Restoration of blood flow and muscle perfusion was evaluated by laser Doppler perfusion imaging. Blood perfusion recovery, enhanced vessel densities, and improvement of function of the ischemia limb were significantly greater in the hi-MSC group than in the MSC or PBS group. Immunochemistry revealed that hi-MSCs had higher expression levels of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor A than those in MSCs. In addition, an endothelial cell-inducing medium showed high expression levels of vascular endothelial growth factor, platelet endothelial cell adhesion molecule-1, and von Willebrand factor in hi-MSCs compared to those in MSCs. These findings suggest that pretreatment of MSCs with a hypoxia condition and implantation of hi-MSCs advances neovascularization capability with enhanced therapeutic angiogenic effects in a murine hindlimb ischemia model.

Short stature is associated with low flow-mediated vasodilation in Japanese men.

An inverse association between height and the risk of cardiovascular disease has been reported. The objective of this study was to examine the association between height and endothelial function assessed by flow-mediated vasodilation (FMD). We evaluated cross-sectional associations of height with FMD in 7682 Japanese men. All participants were divided into four groups based on height: <155.0 cm, 155.0-164.9 cm, 165.0-174.9 cm, and ≥175.0 cm. Subjects in a lower quartile of FMD were defined as subjects having low FMD values. Univariate regression analysis revealed that height was significantly correlated with FMD (r = 0.14, p < 0.001). FMD values were 4.6 ± 3.1% in the <155.0 cm group, 5.2 ± 3.1% in the 155.0-164.9 cm group, 5.7 ± 3.1% in the 165.0-174.9 cm group and 6.1 ± 3.2% in the ≥175.0 cm group. FMD significantly increased in relation to an increase in height. Multiple logistic regression analysis revealed that higher height groups were significantly associated with a decreased risk of low FMD value compared with the <155.0 cm group after adjustments for age, presence of hypertension, dyslipidemia, diabetes, current smoking, and brachial artery diameter. FMD was low in subjects with a short stature compared with that in subjects with tall stature. Individuals with a short stature may require intensive interventions to reduce the risk of cardiovascular events.Clinical Trial Registration Information: URL for Clinical Trials: http://www.umin.ac.jp Registration Number for Clinical Trials: UMIN000012952.

Vascular Damage in the Aorta of Wild-Type Mice Exposed to Ionizing Radiation: Sparing and Enhancing Effects of Dose Protraction.

During medical (therapeutic or diagnostic) procedures or in other settings, the circulatory system receives ionizing radiation at various dose rates. Here, we analyzed prelesional changes in the circulatory system of wild-type mice at six months after starting acute, intermittent, or continuous irradiation with 5 Gy of photons. Independent of irradiation regimens, irradiation had little impact on left ventricular function, heart weight, and kidney weight. In the aorta, a single acute exposure delivered in 10 minutes led to structural disorganizations and detachment of the aortic endothelium, and intima-media thickening. These morphological changes were accompanied by increases in markers for profibrosis (TGF-ß1), fibrosis (collagen fibers), proinflammation (TNF-α), and macrophages (F4/80 and CD68), with concurrent decreases in markers for cell adhesion (CD31 and VE-cadherin) and vascular functionality (eNOS) in the aortic endothelium. Compared with acute exposure, the magnitude of such aortic changes was overall greater when the same dose was delivered in 25 fractions spread over 6 weeks, smaller in 100 fractions over 5 months, and much smaller in chronic exposure over 5 months. These findings suggest that dose protraction alters vascular damage in the aorta, but in a way that is not a simple function of dose rate.

Regenerative medicine for radiation emergencies.

Hiroshima University is a 'medical institution for tertiary radiation emergencies' and a 'medical support organization as a part of the International Atomic Emergency Agency Emergency Preparedness Response-Response and Assistance Network (IAEA EPR-RANET)'. To establish a system of regenerative medicine for radiation emergencies with treatment by implantation of various types of cells derived from induced pluripotent stem (iPS) cells, it is necessary to establish methods of defense against and treatment for radiation-induced damage from nuclear power plant accidents and nuclear terrorism. It is also necessary to develop cell therapy, cellular repair technology and regenerative biotechnology as regenerative medicine for radiation emergencies. Such applications have not been established yet. To develop a regenerative medical system, by using the existing one, for radiation emergencies, we will attempt to manage the cell-processing center to establish a safe and secured iPS cell bank for radiation medicine. By using this iPS cell bank as the central leverage, we will develop an education program for radiation emergency medicine and construct a network of regenerative medicine for radiation emergency medicine.

Smoking status and endothelial function in Japanese men.

It is established that smoking is a major risk factor of atherosclerosis. Endothelial dysfunction occurs in the initial step in the pathogenesis of atherosclerosis and plays a critical role in the development of atherosclerosis. The purpose of this study was to evaluate the association between smoking status and endothelial function in detail in men. We measured flow-mediated vasodilation (FMD) in 2209 Japanese men including 1181 men who had never smoked and 1028 current smokers. All of the participants were divided into five groups by smoking pack-years: never smoker group (= 0), light smoker group (> 0 to 10), moderate smoker group (> 10 to 20), heavy smoker group (> 20 to 30) and excessive smoker group (> 30). FMD significantly decreased in relation to pack-years (6.6 ± 3.4% in the never smoker group, 6.8 ± 3.0% in the light smoker group, 6.5 ± 2.9% in the moderate smoker group, 5.9 ± 2.9% in the heavy smoker group, and 4.9 ± 2.7% in the excessive smoker group; P < 0.001). After adjustment for age (≥ 65 years), body mass index, systolic blood pressure, low-density lipoprotein cholesterol, glucose, and year of recruitment, FMD was significantly smaller in the excessive smoker group than in the never smoker group as a reference group (OR 1.95, 95% CI 1.42 to 2.67; P < 0.001). These findings suggest that FMD decreases with an increase in the number of cigarettes smoked and that excessive smoking is associated with endothelial dysfunction. Cigarette smoking is harmful to vascular function in men who are heavy smokers.

Bach1 plays an important role in angiogenesis through regulation of oxidative stress.

Bach1 is a known transcriptional repressor of the heme oxygenase-1 (HO-1) gene. The purpose of this study was to determine whether angiogenesis is accelerated by genetic ablation of Bach1 in a mouse ischemic hindlimb model. Hindlimb ischemia was surgically induced in wild-type (WT) mice, Bach1-deficient (Bach1-/-) mice, apolipoprotein E-deficient (ApoE-/-) mice, and Bach1/ApoE double-knockout (Bach1-/-/ApoE-/-) mice. Blood flow recovery after hindlimb ischemia showed significant improvement in Bach1-/- mice compared with that in WT mice. Bach1-/-/ApoE-/- mice showed significantly improved blood flow recovery compared with that in ApoE-/- mice to the level of that in WT mice. Migration of endothelial cells in ApoE-/- mice was significantly decreased compared with that in WT mice. Migration of endothelial cells significantly increased in Bach1-/-/ApoE-/- mice compared with that in ApoE-/- mice to the level of that in WT mice. The expression levels of HO-1, peroxisome proliferator-activated receptor γ co-activator-1α, angiopoietin 1, and fibroblast growth factor 2 in endothelial cells isolated from Bach1-/-/ApoE-/- mice were significantly higher than those in ApoE-/- mice. Oxidative stress assessed by anti-acrolein antibody staining in ischemic tissues and urinary 8-isoPGF2α excretion were significantly increased in ApoE-/- mice compared with those in WT and Bach1-/- mice. Oxidative stress was reduced in Bach1-/-/ApoE-/- mice compared with that in ApoE-/- mice. These findings suggest that genetic ablation of Bach1 plays an important role in ischemia-induced angiogenesis under the condition of increased oxidative stress. Bach1 could be a potential therapeutic target to reduce oxidative stress and potentially improve angiogenesis for patients with peripheral arterial disease.

Relationship between cell number and clinical outcomes of autologous bone-marrow mononuclear cell implantation in critical limb ischemia.

Cell therapy using intramuscular injections of autologous bone-marrow mononuclear cells (BM-MNCs) improves clinical symptoms and can prevent limb amputation in atherosclerotic peripheral arterial disease (PAD) patients with critical limb ischemia (CLI). The purpose of this study was to evaluate the effects of the number of implanted BM-MNCs on clinical outcomes in atherosclerotic PAD patients with CLI who underwent cell therapy. This study was a retrospective observational study with median follow-up period of 13.5 years (range, 6.8-15.5 years) from BM-MNC implantation procedure. The mean number of implanted cells was 1.2 ± 0.7 × 109 per limb. There was no significant difference in number of BM-MNCs implanted between the no major amputation group and major amputation group (1.1 ± 0.7 × 109 vs. 1.5 ± 0.8 × 109 per limb, P = 0.138). There was also no significant difference in number of BM-MNCs implanted between the no death group and death group (1.5 ± 0.9 × 109 vs. 1.8 ± 0.8 × 109 per patient, P = 0.404). Differences in the number of BM-MNCs (mean number, 1.2 ± 0.7 × 109 per limb) for cell therapy did not alter the major amputation-free survival rate or mortality rate in atherosclerotic PAD patients with CLI. A large number of BM-MNCs will not improve limb salvage outcome or mortality.

Daily Low-intensity Pulsed Ultrasound Ameliorates Renal Fibrosis and Inflammation in Experimental Hypertensive and Diabetic Nephropathy.

The estimated morbidity rate of chronic kidney disease is 8% to 16% worldwide, and many patients with chronic kidney disease eventually develop renal failure. Thus, the development of new therapeutic strategies for preventing renal failure is crucial. In this study, we assessed the effects of daily low-intensity pulsed ultrasound (LIPUS) therapy on experimental hypertensive nephropathy and diabetic nephropathy. Unilateral nephrectomy and subcutaneous infusion of angiotensin II via osmotic mini-pumps were used to induce hypertensive nephropathy in mice. Immunohistochemistry revealed that daily LIPUS treatment ameliorated renal fibrosis and infiltration of inflammatory cells induced by angiotensin II. A similar therapeutic effect was also observed in mice with angiotensin II-induced hypertensive nephropathy in which splenectomy was performed. In addition, LIPUS treatment significantly decreased systolic blood pressure after 21 days. Subsequently, db/db mice with unilateral nephrectomy developed proteinuria; daily LIPUS treatment significantly reduced proteinuria after 42 days. In addition, immunohistochemistry revealed that renal fibrosis was significantly ameliorated by LIPUS treatment. Finally, LIPUS stimulation suppressed TGF-ß1 (transforming growth factor-ß1)-induced phosphorylation of Smad2 and Smad3 in HK-2 (human proximal tubular cell line) cells. LIPUS treatment may be a useful therapy for preventing the progression of renal fibrosis in patients with chronic kidney disease.

Ionizing Irradiation Induces Vascular Damage in the Aorta of Wild-Type Mice.

There has been a recent upsurge of interest in the effects of ionizing radiation exposure on the circulatory system, because a mounting body of epidemiological evidence suggests that irradiation induces cardio- and cerebrovascular disease at a much lower dose and lower dose rate than previously considered. The goal of our project is to determine whether dose protraction alters radiation effects on the circulatory system in a mouse model. To this end, the use of wild-type mice is pivotal albeit without manifestation of vascular diseases, because disease models (e.g., apolipoprotein E-deficient mice) are prone to hormetic responses following protracted exposures. As such, here, we first set out to analyze prelesional changes in the descending thoracic aorta of wild-type mice up to six months after a single acute exposure to 0 or 5 Gy of 137Cs γ-rays. Scanning electron microscopy demonstrated that irradiation facilitated structural disorganizations and detachment of the aortic endothelium. The Miles assay with an albumin-binding dye Evans Blue revealed that irradiation enhanced vascular permeability. Immunofluorescence staining showed that irradiation led to partial loss of the aortic endothelium (evidenced by a lack of adhesion molecule CD31 and 4',6-diamidino-2-phenylindole (DAPI) signals), a decrease in endothelial nitric oxide synthase and adherens junction protein (vascular endothelial (VE)-cadherin) in the aortic endothelium, along with an increase in inflammation (tumor necrosis factor (TNF)-α) and macrophage (F4/80) markers in the aorta. These findings suggest that irradiation produces vascular damage manifested as endothelial cell loss and increased vascular permeability, and that the decreased adherens junction and the increased inflammation lead to macrophage recruitment implicated in the early stage of atherosclerosis.

A Comparison of Adrenalectomy and Eplerenone on Vascular Function in Patients with Aldosterone-producing Adenoma.

CONTEXT: It remains unclear whether adrenalectomy has more beneficial effects than treatment with a mineralocorticoid receptor antagonist on vascular function in patients with aldosterone-producing adenoma (APA). OBJECTIVE: The aim of this study was to compare the effects of adrenalectomy and treatment with eplerenone on vascular function in patients with APA. DESIGN, SETTING, AND PATIENTS: Flow-mediated vasodilation (FMD), as an index of endothelium-dependent vasodilation, and nitroglycerine-induced vasodilation (NID), as an index of endothelium-independent vasodilation, were measured to assess vascular function before and after a 3-month treatment with eplerenone and at 3 months after adrenalectomy in 23 patients with APA. RESULTS: Flow-mediated vasodilation and NID after adrenalectomy were significantly higher than those before treatment with eplerenone (5.4 ± 2.6% vs 2.7 ± 1.9% and 14.8 ± 4.7% vs 9.6 ± 4.6%, P < 0.01, respectively) and those after treatment with eplerenone (5.4 ± 2.6% vs 3.1 ± 2.3% and 14.8 ± 4.7% vs 11.0 ± 5.3%, P < 0.01 and P = 0.03, respectively), while treatment with eplerenone did not alter FMD and NID compared with those before treatment with eplerenone. After adrenalectomy, the increase in FMD and NID were significantly correlated with a decrease in plasma aldosterone concentration and a decrease in the aldosterone-renin ratio. There were no significant relationships between FMD and changes in other parameters or between NID and changes in other parameters. CONCLUSIONS: Adrenalectomy, but not treatment with eplerenone, improved vascular function in patients with APA. Adrenalectomy may be more effective than treatment with eplerenone for reducing the incidence of future cardiovascular events in patients with APA. Clinical Trial Information: URL for the clinical trial: http://UMIN; Registration Number for the clinical trial: UMIN000003409.

Review of the Long-term Effects of Autologous Bone-Marrow Mononuclear Cell Implantation on Clinical Outcomes in Patients with Critical Limb Ischemia.

Critical limb ischemia (CLI) is associated with a high risk of limb amputation. It has been shown that cell therapy is safe and has beneficial effects on ischemic clinical symptoms in patients with CLI. The aim of this study was to further investigate the outcomes of intramuscular injection of autologous bone-marrow mononuclear cells (BM-MNCs) in a long-term follow-up period in atherosclerotic peripheral arterial disease (PAD) patients who have no optional therapy. This study was a retrospective and observational study that was carried out to evaluate long-term clinical outcomes in 42 lower limbs of 30 patients with atherosclerotic PAD who underwent BM-MNC implantation. The median follow-up period was 9.25 (range, 6-16) years. The overall amputation-free rates were 73.0% at 5 years after BM-MNC implantation and 70.4% at 10 years in patients with atherosclerotic PAD. The overall amputation-free rates at 5 years and at 10 years after implantation of BM-MNCs were significantly higher in atherosclerotic PAD patients than in internal controls and historical controls. There were no significant differences in amputation rates between the internal control group and historical control group. The rate of overall survival was not significantly different between the BM-MNC implantation group and the historical control group. Implantation of autologous BM-MNCs is feasible for a long-term follow-up period in patients with CLI who have no optional therapy.

Eplerenone improves endothelial function and arterial stiffness and inhibits Rho-associated kinase activity in patients with idiopathic hyperaldosteronism: a pilot study.

OBJECTIVE: Primary aldosteronism is one of the most common cause of secondary hypertension. It is well known that the incidence of cardiovascular events is higher in patients with primary aldosteronism than in patients with essential hypertension. In a previous study, we showed that aldosterone-producing adenoma is associated with vascular function and structure. The aim of this study was to evaluate the effects of eplerenone on vascular function in the macrovasculature and microvasculature, arterial stiffness and Rho-associated kinase (ROCK) activity in patients with idiopathic hyperaldosteronism (IHA). METHODS: Vascular function, including reactive hyperemia index (RHI), flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID), arterial stiffness including brachial-ankle pulse wave velocity (baPWV) and brachial intima-media thickness (IMT) and ROCK activity in peripheral leukocytes were measured before and after 12 weeks of treatment with eplerenone in 50 patients with IHA. RESULTS: After 12 weeks, eplerenone decreased the aldosterone renin ratio but did not alter SBP and DBP. Eplerenone treatment increased log RHI from 0.56 ±â€Š0.25 to 0.69 ±â€Š0.25 (P < 0.01) and NID from 12.8 ±â€Š5.8 to 14.9 ±â€Š6.9% (P = 0.02) and it decreased baPWV from 1540 ±â€Š263 to 1505 ±â€Š281 (P = 0.04) and ROCK activity from 1.20 ±â€Š0.54 to 0.89 ±â€Š0.42 (P < 0.01), whereas there was no significant change in FMD (increase from 4.6 ±â€Š3.4 to 4.6 ±â€Š3.6%, P = 0.99) or brachial IMT (decrease from 0.28 ±â€Š0.07 to 0.28 ±â€Š0.04 mm, P = 0.14). CONCLUSION: Eplerenone improves microvascular endothelial function, vascular smooth muscle function, arterial stiffness and ROCK activity in patients with IHA. CLINICAL TRIAL REGISTRATION INFORMATION: URL for Clinical Trial: http://UMIN; Registration Number for Clinical Trial: UMIN000003409.

Microvascular endothelial function is impaired in patients with idiopathic hyperaldosteronism.

The aims were to evaluate the relationship between idiopathic hyperaldosteronism (IHA) and grade of vascular function in the macrovasculature and microvasculature. Vascular function, including reactive hyperemia index (RIH), flow-mediated vasodilation (FMD), and nitroglycerine-induced vasodilation (NID) were evaluated in 52 patients with IHA, 53 patients with aldosterone-producing adenoma (APA), and 52 age-, sex-, and blood pressure-matched patients with essential hypertension (EHT). Log RHI was lower in the IHA and APA groups than in the EHT group (0.54 ± 0.25 and 0.55 ± 0.23 versus 0.79 ± 0.28; P < 0.01, respectively). FMD was lower in the APA group than in the EHT group (3.4 ± 2.1% versus 4.8 ± 2.8%; P = 0.02), whereas there was no significant difference in FMD between the IHA and the APA and EHT groups. NID was lower in the APA group than in the EHT group (10.0 ± 4.5% versus 12.5 ± 5.7%; P = 0.03), whereas there was no significant difference in NID between the IHA, APA, and EHT groups. Multiple regression analysis revealed an association of log RHI with plasma aldosterone concentration (t = -2.24; P = 0.03) and an association of FMD with plasma aldosterone concentration (t = -3.07; P < 0.01). Microvascular endothelial function was impaired in patients with IHA compared with that in patients with EHT.