Single-cell transcriptomics identifies adipose tissue CD271+ progenitors for enhanced angiogenesis in limb ischemia.

Therapeutic angiogenesis using mesenchymal stem/stromal cell grafts have shown modest and controversial effects in preventing amputation for patients with critical limb ischemia. Through single-cell transcriptomic analysis of human tissues, we identify CD271+ progenitors specifically from subcutaneous adipose tissue (AT) as having the most prominent pro-angiogenic gene profile distinct from other stem cell populations. AT-CD271+ progenitors demonstrate robust in vivo angiogenic capacity over conventional adipose stromal cell grafts, characterized by long-term engraftment, augmented tissue regeneration, and significant recovery of blood flow in a xenograft model of limb ischemia. Mechanistically, the angiogenic capacity of CD271+ progenitors is dependent on functional CD271 and mTOR signaling. Notably, the number and angiogenic capacity of CD271+ progenitors are strikingly reduced in insulin-resistant donors. Our study highlights the identification of AT-CD271+ progenitors with in vivo superior efficacy for limb ischemia. Furthermore, we showcase comprehensive single-cell transcriptomics strategies for identification of suitable grafts for cell therapy.

The widely used Ucp1-CreEvdr transgene elicits complex developmental and metabolic phenotypes.

Bacterial artificial chromosome transgenic models, including most Cre-recombinases, enable potent interrogation of gene function in vivo but require rigorous validation as limitations emerge. Due to its high relevance to metabolic studies, we performed comprehensive analysis of the Ucp1-CreEvdr line which is widely used for brown fat research. Hemizygotes exhibited major brown and white fat transcriptomic dysregulation, indicating potential altered tissue function. Ucp1-CreEvdr homozygotes also show high mortality, growth defects, and craniofacial abnormalities. Mapping the transgene insertion site revealed insertion in chromosome 1 accompanied by large genomic alterations disrupting several genes expressed in a range of tissues. Notably, Ucp1-CreEvdr transgene retains an extra Ucp1 gene copy that may be highly expressed under high thermogenic burden. Our multi-faceted analysis highlights a complex phenotype arising from the presence of the Ucp1-CreEvdr transgene independently of the intended genetic manipulations. Overall, comprehensive validation of transgenic mice is imperative to maximize discovery while mitigating unexpected, off-target effects.

Single cell transcriptomics identifies adipose tissue CD271+ progenitors for enhanced angiogenesis in limb ischemia.

Therapeutic angiogenesis using mesenchymal stem/stromal cell grafts have shown modest and controversial effects in preventing amputation for patients with critical limb ischemia. Through single-cell transcriptomic analysis of human tissues, we identified CD271 + progenitors specifically from subcutaneous adipose tissue (AT) as having the most prominent pro-angiogenic gene profile distinct from other stem cell populations. AT-CD271 + progenitors demonstrated robust in vivo angiogenic capacity, over conventional adipose stromal cell grafts, characterized by long-term engraftment, augmented tissue regeneration, and significant recovery of blood flow in a xenograft model of limb ischemia. Mechanistically, the angiogenic capacity of CD271 + progenitors is dependent on functional CD271 and mTOR signaling. Notably, the number and angiogenic capacity of CD271 + progenitors was strikingly reduced in insulin resistant donors. Our study highlights the identification of AT-CD271 + progenitors with in vivo superior efficacy for limb ischemia. Furthermore, we showcase comprehensive single-cell transcriptomics strategies for identification of suitable grafts for cell therapy. HIGHLIGHTS: Adipose tissue stromal cells have a distinct angiogenic gene profile among human cell sources. CD271 + progenitors in adipose tissue have a prominent angiogenic gene profile. CD271 + progenitors show superior therapeutic capacities for limb ischemia. CD271 + progenitors are reduced and functionally impaired in insulin resistant donors.

Important Role of Endogenous Nerve Growth Factor Receptor in the Pathogenesis of Hypoxia-Induced Pulmonary Hypertension in Mice.

Pulmonary arterial hypertension (PAH) remains a disease with poor prognosis; thus, a new mechanism for PAH treatment is necessary. Circulating nerve growth factor receptor (Ngfr)-positive cells in peripheral blood mononuclear cells are associated with disease severity and the prognosis of PAH patients; however, the role of Ngfr in PAH is unknown. In this study, we evaluated the function of Ngfr using Ngfr gene-deletion (Ngfr-/-) mice. To elucidate the role of Ngfr in pulmonary hypertension (PH), we used Ngfr-/- mice that were exposed to chronic hypoxic conditions (10% O2) for 3 weeks. The development of hypoxia-induced PH was accelerated in Ngfr-/- mice compared to littermate controls. In contrast, the reconstitution of bone marrow (BM) in Ngfr-/- mice transplanted with wild-type BM cells improved PH. Notably, the exacerbation of PH in Ngfr-/- mice was accompanied by the upregulation of pulmonary vascular remodeling-related genes in lung tissue. In a hypoxia-induced PH model, Ngfr gene deletion resulted in PH exacerbation. This suggests that Ngfr may be a key molecule involved in the pathogenesis of PAH.

Therapeutic angiogenesis for patients with no-option critical limb ischemia by adipose-derived regenerative cells: TACT-ADRC multicenter trial.

BACKGROUND: Patients with critical limb ischemia (CLI) still have a high rate of lower limb amputation, which is associated with not only a decrease in quality of life but also poor life prognosis. Implantation of adipose-derived regenerative cells (ADRCs) has an angiogenic potential for patients with limb ischemia. OBJECTIVES: We investigated safety, feasibility, and efficacy of therapeutic angiogenesis by cell transplantation (TACT) of ADRCs for those patients in multicenter clinical trial in Japan. METHODS: The TACT-ADRC multicenter trial is a prospective, interventional, open-labeled study. Patients with CLI (Fontaine class III-IV) who have no other option for standard revascularization therapy were enrolled in this study. Thirty-four target ischemic limbs of 29 patients were received freshly isolated autologous ADRCs implantation. RESULTS: The overall survival rate at a post-operative period and at 6 months follow-up was 100% at any time points. As a primary endpoint for efficacy evaluation, 32 limbs out of 34 (94.1%) were free from major amputation for 6 months. Numerical rating scale (from 6 to 1) as QOL score, ulcer size (from 317 mm2 at to 109 mm2), and 6-min walking distance (from 255 to 369 m) improved in 90.6%, 83.3%, and 72.2% patients, respectively. CONCLUSIONS: Implantation of autologous ADRCs could be safe and effective for the achievement of therapeutic angiogenesis in the multicenter settings, as a result in no major adverse event, optimal survival rate, and limb salvage for patients with no-conventional option against critical limb ischemia. TRN: jRCTb040190118; Date: Nov. 24th, 2015.

Effect of pulmonary vein isolation on the relationship between left atrial reverse remodeling and sympathetic nerve activity in patients with atrial fibrillation.

PURPOSE: Catheter ablation (CA) to isolate the pulmonary vein, which is an established treatment for atrial fibrillation (AF), is associated with left atrium reverse remodeling (LARR). The intrinsic cardiac autonomic nervous system includes the ganglion plexi adjacent to the pulmonary vein in the left atrium (LA). However, little is known about the effect of CA on the relationship between LARR and sympathetic nerve activity in patients with AF. METHODS: This study enrolled 22 AF patients with a normal left ventricular ejection fraction (LVEF) aged 64.6 ± 12.9 years who were scheduled for CA. Sympathetic nerve activity was evaluated by direct recording of muscle sympathetic nerve activity (MSNA) before and 12 weeks after CA. Blood pressure, heart rate (HR), HR variability, and echocardiography were also measured. RESULTS: The heart rate increased significantly after CA (63 ± 10.9 vs. 70.6 ± 7.7 beats/min, p < 0.01), but blood pressure did not change. A high frequency (HF) and low frequency (LF) of HR variability decreased significantly after ablation, but no significant change in LF/HF was observed. CA significantly decreased MSNA (38.9 ± 9.9 vs. 28 ± 9.1 bursts/min, p < 0.01). Moreover, regression analysis revealed a positive correlation between the percentage change in MSNA and the LA volume index (r = 0.442, p < 0.05). CONCLUSIONS: Our results show that CA for AF reduced MSNA and the decrease was associated with the LA volume index in AF patients with a normal LVEF. These findings suggest that LARR induced by CA for AF decrease sympathetic nerve activity.

Characterization of adipose tissue-derived stromal cells of mice with nonalcoholic fatty liver disease and their use for liver repair.

INTRODUCTION: Freshly isolated uncultured adipose tissue-derived stromal cells (u-ADSCs), containing miscellaneous cells like the relatively abundant mesenchymal stem cells, are attractive for repair and regenerative therapy. However, the detailed characteristics and therapeutic efficacy of u-ADSCs obtained from disease-affected hosts are unknown. We compared the properties of u-ADSCs obtained from wild-type mice and from a mouse model of non-alcoholic steatohepatitis (NASH). METHODS: The NASH model was established by feeding C57BL/6J mice an atherogenic high-fat diet for 4 (NASH (4w)) or 12 weeks (NASH (12w)), followed by the isolation and characterization of u-ADSCs. Wild-type u-ADSCs or NASH-derived u-ADSCs were administered to mice with NASH cirrhosis, followed by analyses of hepatic inflammatory cells, antigen profiles, fibrosis, and gene expression. RESULTS: Wild-type u-ADSCs and NASH-derived u-ADSCs did not show marked differences in surface antigen profiles. In NASH (4w) u-ADSCs, but not NASH (12w) u-ADSCs, the frequencies of the leukocyte markers CD11b, CD45, and CD44 were elevated; furthermore, we observed an increase in the M1/M2 macrophage ratio only in NASH (12w) u-ADSCs. Only in NASH-4w u-ADSCs, the expression levels cell cycle-related genes were higher than those in u-ADSCs. Wild-type u-ADSCs administered to mice with NASH-related cirrhosis decreased the infiltration of CD11b+, F4/80+, and Gr-1+ inflammatory cells, ameliorated fibrosis, and had a restorative effect on liver tissues, as determined by gene expression profiles and the NAFLD activity score. The therapeutic effects of NASH (4w) u-ADSCs and NASH (12w) u-ADSCs on NASH-related cirrhosis were highly similar to the effect of wild-type u-ADSCs, including reductions in inflammation and fibrosis. CONCLUSIONS: NASH-derived u-ADSCs, similar to wild-type u-ADSCs, are applicable for reparative and regenerative therapy in mice with NASH.

Different Responses of Muscle Sympathetic Nerve Activity to Dapagliflozin Between Patients With Type 2 Diabetes With and Without Heart Failure.

Background Sodium-glucose cotransporter 2 inhibitors improve cardiovascular outcomes in patients with diabetes with and without heart failure (HF). However, their influence on sympathetic nerve activity (SNA) remains unclear. The purpose of this study was to evaluate the effect of sodium-glucose cotransporter 2 inhibitors on SNA and compare the responses of SNA to sodium-glucose cotransporter 2 inhibitors in patients with type 2 diabetes with and without HF. Methods and Results Eighteen patients with type 2 diabetes, 10 with HF (65.4±3.68 years) and 8 without HF (63.3±3.62 years), were included. Muscle SNA (MSNA), heart rate, and blood pressure were recorded before and 12 weeks after administration of dapagliflozin (5 mg/day). Sympathetic and cardiovagal baroreflex sensitivity were simultaneously calculated. Brain natriuretic peptide level increased significantly at baseline in patients with HF than those without HF, while MSNA, blood pressure, and hemoglobin A1c did not differ between the 2 groups. Fasting blood glucose and homeostatic model assessment of insulin resistance did not change in either group after administering dapagliflozin. MSNA decreased significantly in both groups. However, the reduction in MSNA was significantly higher in patients with HF than patients with non-HF (-20.2±3.46 versus -9.38±3.65 bursts/100 heartbeats; P=0.049), which was concordant with the decrease in brain natriuretic peptide. Conclusions Dapagliflozin significantly decreased MSNA in patients with type 2 diabetes regardless of its blood glucose-lowering effect. Moreover, the reduction in MSNA was more prominent in patients with HF than in patients with non-HF. These results indicate that the cardioprotective effects of sodium-glucose cotransporter 2 inhibitors may, in part, be attributed to improved SNA.

Clinical trial of autologous adipose tissue-derived regenerative (stem) cells therapy for exploration of its safety and efficacy.

INTRODUCTION: Liver cirrhosis is the ultimate condition of chronic liver diseases. Non-alcoholic steatohepatitis and fatty liver diseases are emerging in association with metabolic syndrome largely due to excess nutrition. Stromal cells of adipose tissue are enriched mesenchymal stem cells which are pluripotent and immunomodulatory, which are expected to be applied for repairing/regenerative therapy of the impaired organs. METHODS: We conducted the multi-institutional clinical trial (Japanese UMIN Clinical Trial Registry: UMIN000022601) of cell therapy using freshly isolated autologous adipose tissue-derived regenerative (stem) cells (ADRCs), which are obtained by the investigational trial device, adipose tissue dissociation device, for liver cirrhosis patients due to non-alcoholic steatohepatitis or fatty liver disease, to exploratory assess efficacy as well as safety of this trial. We completed treatment and 24 weeks follow-up for 7 patients. RESULTS: We observed that 6 out of 7 patients' serum albumin concentration was improved. As for prothrombin activity, 5 out of 7 patients showed improvement. No trial-related adverse events, which were serious or non-serious, was observed. Besides, no malfunction of the investigational trial device was encountered. CONCLUSION: Thus, treatment with autologous ADRCs obtained with the investigational trial device in steatohepatitis-related cirrhosis was confirmed to be safely conductible and potentially promising for the retaining or improving the impaired hepatic reserve.

Circulating nerve growth factor receptor positive cells are associated with severity and prognosis of pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) remains a disease with a poor prognosis, so early detection and treatment are very important. Sensitive and non-invasive markers for PAH are urgently required. This study was performed to identify sensitive markers of the clinical severity and prognosis of PAH. Patients diagnosed with PAH (n = 30) and control participants (n = 15) were enrolled in this observational study. Major EPC and MSC markers (including CD34, CD133, VEGFR2, CD90, PDGFRα, and NGFR) in peripheral blood mononuclear cells (PBMNCs) were assessed by flow cytometry. Associations of these markers with hemodynamic parameters (e.g. mean pulmonary arterial pressure, pulmonary vascular resistance, and cardiac index) were assessed. Patients with PAH were followed up for 12 months to assess the incidence of major adverse events, defined as death or lung transplantation. Levels of circulating EPC and MSC markers in PBMNCs were higher in patients with PAH than in control participants. Among the studied markers, nerve growth factor receptor (NGFR) was significantly positively correlated with hemodynamic parameters. During the 12-month follow-up period, major-event-free survival was significantly higher in patients with PAH who had relatively low frequencies of NGFR positive cells than patients who had higher frequencies. These results suggested that the presence of circulating NGFR positive cells among PBMNCs may be a novel biomarker for the severity and prognosis of PAH.

Myocyte-specific enhancer factor 2c triggers transdifferentiation of adipose tissue-derived stromal cells into spontaneously beating cardiomyocyte-like cells.

Cardiomyocyte regeneration is limited in adults. The adipose tissue-derived stromal vascular fraction (Ad-SVF) contains pluripotent stem cells that rarely transdifferentiate into spontaneously beating cardiomyocyte-like cells (beating CMs). However, the characteristics of beating CMs and the factors that regulate the differentiation of Ad-SVF toward the cardiac lineage are unknown. We developed a simple culture protocol under which the adult murine inguinal Ad-SVF reproducibly transdifferentiates into beating CMs without induction. The beating CMs showed the striated ventricular phenotype of cardiomyocytes and synchronised oscillation of the intracellular calcium concentration among cells on day 28 of Ad-SVF primary culture. We also identified beating CM-fated progenitors (CFPs) and performed single-cell transcriptome analysis of these CFPs. Among 491 transcription factors that were differentially expressed (≥ 1.75-fold) in CFPs and the beating CMs, myocyte-specific enhancer 2c (Mef2c) was key. Transduction of Ad-SVF cells with Mef2c using a lentiviral vector yielded CFPs and beating CMs with ~ tenfold higher cardiac troponin T expression, which was abolished by silencing of Mef2c. Thus, we identified the master gene required for transdifferentiation of Ad-SVF into beating CMs. These findings will facilitate the development of novel cardiac regeneration therapies based on gene-modified, cardiac lineage-directed Ad-SVF cells.

A case of pulmonary arterial hypertension with chronic hepatitis that resulted in hepatosplenomegaly after administration of prostaglandin I2.

The prognosis of pulmonary arterial hypertension (PAH) has significantly improved over the past two decades due to advances in medications, including pulmonary vasodilators. However, the side effects of these drugs remain problematic in some patients. A 51-year-old woman with chronic hepatitis C was diagnosed with PAH 7 years before presenting to our hospital. She was unable to continue her treatment with pulmonary vasodilators due to various side effects. She had a World Health Organization functional class of IV and was started on continuous infusion of prostaglandin I2 (PGI2). This therapy improved her symptoms, including dyspnea and fatigue. However, she began to complain of abdominal distension after 4 months of PGI2 therapy. Computed tomography showed significant hepatosplenomegaly. Her abdominal distension improved slightly after decreasing PGI2 treatment, but her dyspnea on exertion was exacerbated. She died 12 years after diagnosis of PAH due to uncontrollable heart failure. Here, we describe a rare case of PAH with hepatosplenomegaly after administration of PGI2. .

Regenerative Therapy for Liver Cirrhosis Based on Intrahepatic Arterial Infusion of Autologous Subcutaneous Adipose Tissue-Derived Regenerative (Stem) Cells: Protocol for a Confirmatory Multicenter Uncontrolled Clinical Trial.

BACKGROUND: Liver cirrhosis results from chronic hepatitis, and is characterized by advanced fibrosis due to long-term hepatic inflammation. Cirrhosis ultimately leads to manifestations of jaundice, ascites, and encephalopathy, and increases the risk of hepatocellular carcinoma. Once cirrhosis is established, resulting in hepatic failure, no effective treatment is available. Therefore, novel therapies to inhibit disease progression of cirrhosis are needed. OBJECTIVE: The objective of this investigator-initiated clinical trial is to assess the safety and efficacy of autologous adipose tissue-derived regenerative (stem) cell therapy delivered to the liver via the hepatic artery in patients with liver cirrhosis. METHODS: Through consultation with the Japan Pharmaceuticals and Medical Devices Agency, we designed a clinical trial to assess a therapy for liver cirrhosis based on autologous adipose tissue-derived regenerative (stem) cells, which are extracted using an adipose tissue dissociation device. The primary endpoints of the trial are the serum albumin concentration, prothrombin activity, harmful events, and device malfunction. RESULTS: Enrollment and registration were initiated in November 2017, and the follow-up period ended in November 2019. Data analysis and the clinical study report will be completed by the end of March 2020. CONCLUSIONS: Completion of this clinical trial, including data analysis, will provide data on the safety and efficacy of this novel liver repair therapy based on autologous adipose tissue-derived regenerative (stem) cells using an adipose tissue dissociation device. TRIAL REGISTRATION: UMIN Clinical Trials Registry UMIN000022601; https://tinyurl.com/w9uqw3q. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/17904.

Diabetes impairs the angiogenic capacity of human adipose-derived stem cells by reducing the CD271+ subpopulation in adipose tissue.

Type 2 diabetes mellitus is an important risk factor for cardiovascular diseases (CVDs). Therapeutic angiogenesis using adipose-derived stem cells (ADSCs) is attractive for CVD therapy. However, although it would be critical for ADSC application on CVD therapy, whether and how diabetes impairs human ADSC therapeutic potential is still uncertain. In this study, we aimed to investigate the impact of diabetes on the angiogenic potential of ADSCs in patients with CVDs, with special focus on stemness-related genes and cellular alteration of ADSCs. We established cultured ADSCs from diabetic (DM-ADSCs) and non-diabetic patients (nonDM-ADSCs) with CVDs. DM-ADSCs demonstrated limited proliferative capacity and reduced paracrine capacity of VEGF, with lower expression of the stemness gene SOX2. Angiogenic capacity and ADSC engraftment were assessed using xenograft experiments in a hindlimb ischemia model of athymic nude mice. Consistent with the results of in vitro assays, DM-ADSCs did not rescue limb ischemia. In contrast, nonDM-ADSCs induced neovascularization with enhanced engraftment. To elucidate the mechanism underlying these ADSC changes, we compared the surface marker profiles of freshly isolated ADSCs obtained from diabetic and non-diabetic patients by flow cytometry. Among studied subsets, the CD34+CD31-CD271+ subpopulation was reduced in the adipose tissues of diabetic patients. In addition, SOX2 expression and proliferative capacity were considerably reduced in nonDM-ADSCs derived from the stromal vascular fraction (SVF) with depletion of CD271+ cells (p < 0.01). Our observations elucidated that reduced CD271+ subpopulation is critical for the impairment of ADSCs in diabetic patients. Further investigations on the CD271+ subset of ADSCs might provide novel insights into the mechanisms and solutions for diabetes-related ADSC dysfunction in cell therapy.

Sphigosine-1-phosphate receptor 1 promotes neointimal hyperplasia in a mouse model of carotid artery injury.

Vascular remodeling, resulting from proliferation and migration of vascular smooth muscle cells (VSMCs), is a major cause of atherosclerosis and restenosis. The lysophospholipid mediator sphingosine-1-phosphate (S1P) regulates proliferation and migration of VSMCs via S1P-specific G protein-coupled receptors, including S1P receptor 1 (S1PR1) to S1PR3. However, the role of S1PR1 in vascular remodeling is not well understood. Therefore, in this study, we aimed to investigate the effect of S1PR1 on neointimal hyperplasia in a carotid artery ligation mouse model using transgenic C57Bl/6 mice that overexpressed S1PR1 (Tg-S1PR1) under the control of α-smooth muscle actin promoter. We found that S1PR1 expression in carotid artery was upregulated after carotid artery ligation in non-transgenic (nTg) mice. Tg-S1PR1 mice showed enhanced ligation-induced neointimal hyperplasia with increased neointimal cell proliferation, compared with control nTg mice. VSMCs isolated from Tg-S1PR1 mice showed enhanced proliferation and migration in response to S1P stimulation. VSMCs from Tg-S1PR1 mice showed greater expression of interleukin-6 (IL-6) compared with nTg mouse-derived VSMCs, and administration of IL-6-neutralizing antibody into Tg-S1PR1 mice suppressed neointimal hyperplasia. These results suggest that S1P-S1PR1 signaling plays an important role in neointimal hyperplasia after vascular injury via IL-6 production.

Endogenous muscle atrophy F-box is involved in the development of cardiac rupture after myocardial infarction.

Muscle atrophy F-box (MAFbx/atrogin-1), an E3 ubiquitin ligase, is a crucial mediator of skeletal muscle atrophy and cardiac hypertrophy in response to pressure overload and exercise. The role of MAFbx in the regulation of cardiac remodeling after myocardial infarction (MI) remains unclear. Permanent coronary ligation of the left coronary artery was performed on MAFbx knockout (KO) and wild-type (WT) mice and MAFbx expression in the WT mice was shown to be significantly increased in the left ventricles after MI. The mortality rate due to post-MI cardiac rupture was significantly decreased in MAFbx KO mice compared to that in the WT mice. DNA microarray and mRNA expression analyses revealed that the upregulation of genes involved in inflammatory processes and cell motility of leukocytes and neutrophils, including Mmp9, Il1b, Cxcl2, and Nlrp3, was significantly attenuated in MAFbx KO mice 1 day after MI. MAFbx downregulation inhibited nuclear factor-κB (Nfkb) activation after MI. Flow cytometry results demonstrated that the myocardial infiltration of neutrophils was suppressed in MAFbx KO mice 1 day after MI. Nlrp3 and Il1b protein levels were decreased in MAFbx KO mice compared with those in the WT mice. MAFbx downregulation significantly attenuated Tnfa-induced Cxcl2, Il1b, and Nlrp3 expression in cardiomyocytes. We conclude that MAFbx plays an important role in the mediation of excessive inflammation, including neutrophil infiltration, inflammasome formation, and production of proinflammatory cytokines through the activation of Nfkb, promoting cardiac rupture after MI.

Significant Association Between Coronary Artery Low-Attenuation Plaque Volume and Apnea-Hypopnea Index, But Not Muscle Sympathetic Nerve Activity, in Patients With Obstructive Sleep Apnea Syndrome.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with augmented sympathetic nerve activity and cardiovascular diseases. However, the interaction between coronary artery plaque characteristics and sympathetic nerve activity remains unclear. The purpose of this study was to clarify the relationships between coronary artery plaque characteristics, sleep parameters and single- and multi-unit muscle sympathetic nerve activity (MSNA) in OSAS patients. Methods and Results: A total of 32 OSAS patients who underwent full-polysomnography participated in this study. The coronary plaque volume was calculated with 320-slice coronary computed tomography (CT). Single- and multi-unit MSNA were obtained during the daytime within 1 week from full-polysomnography. Patients were divided into 2 groups according to their apnea-hypopnea index (AHI) score (mild-moderate group, AHI <30; and severe group, AHI ≥30). There were no group differences in risk factors for atherosclerosis; however, severe AHI patients showed significantly high single-unit MSNA, and low- and intermediate-attenuation plaque volumes. In regression analysis, the plaque volume of any CT value was not associated with single- or multi-unit MSNA; only AHI significantly correlated with low-attenuation plaque volume (R=0.52, P<0.05). CONCLUSIONS: Our findings provided the evidence that AHI is an independent predictor for low-attenuated, vulnerable plaque volume, but not daytime MSNA, in patients with OSAS.

Differential effects of lipophilic and hydrophilic statins on muscle sympathetic nerve activity in heart failure with preserved left ventricular ejection fraction.

Augmented sympathetic nerve activity is associated with heart failure with preserved left ventricular ejection fraction (HFpEF). Lipophilic statins reduce sympathetic nerve activity in patients with heart failure with reduced left ventricular ejection fraction. However, little is known about whether all types of statins, regardless of solubility, reduce sympathetic nerve activity in HFpEF. We evaluated the effect of atorvastatin, a lipophilic statin, and rosuvastatin, a hydrophilic statin, on muscle sympathetic nerve activity (MSNA) in HFpEF patients. This study was conducted as a prospective, randomized, open-label, crossover trial. Ten HFpEF patients with untreated hyperlipidemia participated in this study. Subjects were assigned to either the atorvastatin (lipophilic) or the rosuvastatin (hydrophilic) group with each drug administered for 8 weeks. Atorvastatin and rosuvastatin treatment resulted in a similar reduction in low-density lipoprotein cholesterol (LDL-C) levels. There was no difference in the effect of either treatment on blood pressure, heart rate, or left ventricular function. Atorvastatin significantly decreased MSNA frequency compared with baseline (31.5 ±â€¯6.3 vs. 47.5 ±â€¯10.7 bursts/min, p < 0.01), but rosuvastatin had no effect on MSNA (40.9 ±â€¯7.3 bursts/min). MSNA was significantly lower in the atorvastatin group than rosuvastatin group (p < 0.05). However, the reduction in MSNA seen in either group did not correlate with the reduction in LDL-C. No significant differences were observed in either the baroreflex control of heart rate or MSNA between the two groups. These results suggest that lipophilic statins have a favorable effect on sympathetic nerve activity beyond lowering LDL-C in HFpEF, but hydrophilic statins do not.