It has been reported that accumulation of senescent cells in various tissues contributes to pathological aging and that elimination of senescent cells (senolysis) improves age-associated pathologies. Here, we demonstrate that inhibition of sodium-glucose co-transporter 2 (SGLT2) enhances clearance of senescent cells, thereby ameliorating age-associated phenotypic changes. In a mouse model of dietary obesity, short-term treatment with the SGLT2 inhibitor canagliflozin reduced the senescence load in visceral adipose tissue and improved adipose tissue inflammation and metabolic dysfunction, but normalization of plasma glucose by insulin treatment had no effect on senescent cells. Canagliflozin extended the lifespan of mice with premature aging even when treatment was started in middle age. Metabolomic analyses revealed that short-term treatment with canagliflozin upregulated 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside, enhancing immune-mediated clearance of senescent cells by downregulating expression of programmed cell death-ligand 1. These findings suggest that inhibition of SGLT2 has an indirect senolytic effect by enhancing endogenous immunosurveillance of senescent cells. Katsuumi, Shimizu, Suda et al. report that SGLT2 inhibition reduces the senescence burden and alleviates aging traits in mice. The authors demonstrate an indirect mechanism of senescent cell removal, through enhancing immunosurveillance.

Introduction: From the patients and the mice with atherosclerosis, we found senescence-associated glycoprotein (SAGP-protein) was upregulated in macrophage and vascular endothelial cells. Analysis of transcriptome data from human vascular endothelial cells (HUVECs) revealed the enrichment of SAGP-protein in the HUVECs with senescent status. Based on molecular targeting strategy, we have developed a senolytic vaccine (SAGP-vaccine), which could eliminate SAGP-high senescent cells, leading to amelioration of age-associated pathologic condition including diabetes and atherosclerosis in mice. Since previous studies have reported the positive correlation between SAGP-protein and another age-associated disorder, Alzheimer’s disease (AD), we hypothesize that SAGP-vaccine would also be a treatment to AD. Purpose: This study was aimed to examine the efficacy of SAGP-vaccine in improving AD pathology and degeneration in AD mouse model. Methods: Mice with knock-in of human mutant amyloid precursor protein (APP NL-G-F ) (APP-KI) were treated with control vaccine or SAGP-vaccine at 2 and 4 months old. Behavior tests were performed from 6 months old, and sacrificed afterwards. Brain samples were harvested for further molecular-biological analysis. Results: APP-KI mice with SAGP-vaccination showed the significant improvement in behavior tests along with the reduction of SAGP expression and APP deposition in brain tissue. Furthermore, SAGP-vaccination significantly reduced expression of inflammatory molecules. Consist with previous studies, SAGP was mainly colocalized with microglia, which is the possible target of SAGP-vaccine. Conclusions: SAGP-vaccine would be a sufficient treatment to alleviate amyloid beta-induced pathogenesis in the brain and mitigate the impaired behaviors of AD.

Background: The prognosis of pulmonary hypertension (PH) associated with connective tissue diseases related to interstitial pneumonia (CTD-IP PH) is relatively good among patients with PH and lung disease. However, the impact of pulmonary vasodilator treatment on the prognosis of CTD-IP PH compared with that of PH-induced chronic lung disease (group-3 PH) remains unclear.Methods: From 2012 to 2022, 50 patients with lung parenchymal lesions diagnosed with PH (mean pulmonary arterial pressure >20 mmHg) at Juntendo University Hospital were divided into two groups: CTD-IP PH (30 patients) and group 3-PH (20 patients). The impact of pulmonary vasodilator treatment and the use of long-term oxygen therapy (LTOT) on the prognosis of each group was examined retrospectively.Results: The prognosis of CTD-IP PH was significantly better compared to group-3 PH. While the treatment with pulmonary vasodilators did not affect the prognosis in group 3-PH, the prognosis of the patients treated with vasodilators in the CTD-IP PH group was significantly better than that of the non-treated patients. Treatment with multi-pulmonary vasodilators did not affect the prognosis in CTD-IP PH. Although the prognosis for the patients with LTOT was poor in all registered patients in the present study, treatment with pulmonary vasodi-lators improved the prognosis even under the use of LTOT in CTD-IP PH (P = 0.002). In a multivariate analysis of the CTD-IP PH group, pulmonary vasodilator treatment was an independent factor for better prognosis.Conclusion: Treatment with a pulmonary vasodilator for CTD-IP PH may improve the prognosis, even in patients requiring LTOT.

Background: Group 2 pulmonary hypertension (PH) represents PH caused by left heart disease (PH-LHD). LHD induces left-sided filling and PH, finally leading to pulmonary vascular remodeling. Tofogliflozin (TOFO) is a sodium-glucose cotransporter 2 (SGLT2) inhibitor used in the treatment of diabetes. Recent studies have shown that SGLT2 inhibitors have beneficial effects on heart failure, but the effects of SGLT2 inhibitors on PH-LHD remain unclear. We hypothesized that TOFO has protective effects against pulmonary vascular remodeling in PH-LHD mice. Methods: We generated two murine models of PH-LHD: a transverse aortic constriction (TAC) model; and a high -fat diet (HFD) model. C57BL/6J mice were subjected to TAC and treated with TOFO (3 mg/kg/day) for 3 weeks. AKR/J mice were fed HFD and treated with TOFO (3 mg/kg/day) for 20 weeks. We then measured physical data and right ventricular systolic pressure (RVSP) and performed cardiography. Human pulmonary artery smooth muscle cells (PASMCs) were cultured and treated with TOFO. Results: Mice treated with TOFO demonstrated increased urine glucose levels. TAC induced left ventricular hyper-trophy and increased RVSP. TOFO treatment improved RVSP. HFD increased body weight (BW) and RVSP com-pared with the normal chow group. TOFO treatment ameliorated increases in BW and RVSP induced by HFD. Moreover, PASMCs treated with TOFO showed suppressed migration. Conclusions: TOFO treatment ameliorated right heart overload and pulmonary vascular remodeling for PH-LHD models, suggesting that SGLT2 inhibitors are effective for treating PH-LHD.(c) 2022 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Introduction: Sodium-glucose co-transporter 2 (SGLT2) inhibitors have been developed as a new class of anti-diabetic drug, and shown cardio- and renal-protective effects in patients with diabetes, heart failure, and chronic kidney diseases. SGLT2 inhibitor also has effect to expand lifespan in aged mice, suggesting anti-aging effect. But the detailed machinery of these protective effects is still to be clarified. Here we demonstrate that canagliflozin has a effect to eliminate senescent cells from pathological tissues, so-called "senolysis" in murine aging or age-related disease models. Methods: Canagliflozin mixed in food at 0.03% (w/w) was administered for up to 4 weeks to high-fat-fed diabetic mice, for 2 weeks to ApoE-knockout atherosclerotic mice model, for 20 weeks for chronological aged mice, and for lifetime to Zmpste-knockout progeroid mice. Burden of senescent cell accumilation as well as pathological or aged phenotype were measured in each mice model. Results: Canagliflozin reduced senescent cells in visceral adipose tissue within 1 week. Also, we found that senolytic effect of canagliflozin was provided through enhancing endogenous senolytic function by immune cells such as CD8+T cells. This machinery was mediated by enhanced AMPK signaling through incrase of endogenous AICAR production, which leads to the downregulation of PD-L1 expression on senescent cells. Oppositely, inhibition of AMPK signaling with Compound C administration (10mg/kg ip daily) resulted in abolishing senolytic effect of canagliflozin. Furthermore, canagliflozin reduced their senescent cell burden and alleviated atherosclerosis in ApoE-knockout mice, extended lifespan in progeroid mice, and altered physical function in aged mice. Conclusions: Our results showed new aspect of protective efficacy of SGLT2 inhibitors and would be promising evidence that SGLT2 inhibitors can be used as not only cardio- or renal-protective drugs but also anti-aging drugs.

Background and objective Remodelling of pulmonary arteries (PA) contributes to the progression of pulmonary hypertension (PH). Periostin, a matricellular protein, has been reported to be involved in the development of PH. We examined the role of periostin in the pathogenesis of PH using different types of experimental PH. Methods PH was induced by vascular endothelial growth factor receptor antagonist (Sugen5416) plus hypoxic exposure (SuHx) and venous injection of monocrotaline-pyrrole (MCT-P) in wild-type (WT) and periostin(-/-) mice. Pulmonary haemodynamics, PA remodelling, expression of chemokines and fibroblast growth factor (FGF)-2, accumulation of macrophages to small PA and the right ventricle (RV) were examined in PH-induced WT and periostin(-/-) mice. Additionally, the role of periostin in the migration of macrophages, human PA smooth muscle (HPASMCs) and endothelial cells (HPMVECs) was investigated. Results In PH induced by SuHx and MCT-P, PH and accumulation of M2 macrophage to small PA were attenuated in periostin(-/-) mice. PA remodelling post-SuHx treatment was also mild in periostin(-/-) mice compared to WT mice. Expression of macrophage-associated chemokines and FGF-2 in lung tissue, and accumulation of CD68-positive cells in the RV were less in SuHx periostin(-/-) than in SuHx WT mice. Periostin secretion in HPASMCs and HPMVECs was enhanced by transforming growth factor-beta. Periostin also augmented macrophage, HPASMCs and HPMVECs migration. Separately, serum periostin levels were significantly elevated in patients with PH compared to healthy controls. Conclusion Periostin is involved in the development of different types of experimental PH, and may also contribute to the pathogenesis of human PH.

Background: Pulmonary hypertension (PH) is characterized by increased pulmonary artery pressure and develops right heart failure. Parathyroid hormone (PTH) is secreted from parathyroid gland and play a critical role in calcium homeostasis. Recent studies have suggested that PTH also acts on the cardiovascular system and affects cardiovascular prognosis. We hypothesized that PTH would play a role in the pathogenesis of PH. Object: This study aimed to investigate the effect of PTH on pulmonary hemodynamics. Method: We measured serum PTH levels in patients who were suspected of PH and underwent right heart catheter examination. We used two types of PH animal models, hypoxia (Hx)-induced PH mouse model and Sugen/hypoxia (SuHx)-induced PH rat model. Hx mice were administered PTH daily for 3 weeks. SuHx rats underwent parathyroidectomy, after which they received SuHx treatment for 10weeks. We measured physical data and right ventricular systolic pressure (RVSP) in these models. We cultured pulmonary artery smooth muscle cell (PASMC) treated with PTH to analyze cell signaling, proliferation and migration. Result: We enrolled 20 participants. PTH concentration was significantly correlated with mean pulmonary artery pressure and pulmonary vascular resistance. PTH treatment exacerbated right ventricular hypertrophy and increased RVSP (33.6mmHg vs. 48.2mmHg) in Hx mice compared with non-treated Hx mice(Figure). Conversely, parathyroidectomy significantly attenuated right ventricular hypertrophy and reduced RVSP (54.2mmHg vs. 29.3mmHg) in SuHx rats compared with sham-operated SuHx rats. PTH promoted migration and proliferation through ERK signaling in PASMC. Conclusion: Our clinical and experimental data demonstrated a critical role of PTH in the development of PH and suggested that PTH would be a novel therapeutic target for PH treatment.

BACKGROUND:Heart failure is a severe condition often involving pulmonary hypertension (PH). Soluble low-density lipoprotein receptor with 11 ligand-binding repeats (sLR11) has been associated with pulmonary artery hypertension. We examined whether sLR11 correlates with PH in left heart disease and can be used as a predictive marker.METHOD:We retrospectively analyzed patients with severe mitral regurgitation who underwent right heart catheterization before surgery for valve replacement or valvuloplasty from November 2005 to October 2012 at Juntendo University. We measured sLR11 levels before right heart catheterization and analyzed correlations with pulmonary hemodynamics. We compared prognoses between a group with normal sLR11 (≤9.4 ng/ml) and a group with high sLR11 (>9.4 ng/ml). Follow-up was continued for 5 years, with end points of hospitalization due to HF and death due to cardiovascular disease.RESULTS:Among 34 patients who met the inclusion criteria, sLR11 correlated with mean pulmonary artery pressure (r = 0.54, p<0.001), transpulmonary pressure gradient (r = 0.42, p = 0.012), pulmonary vascular resistance (r = 0.36, p<0.05), and log brain natriuretic peptide (BNP). However, logBNP did not correlate with pulmonary vascular resistance (p = 0.6). Levels of sLR11 were significantly higher in the 10 patients with PH (14.4±4.3 ng/ml) than in patients without PH (9.9±3.9 ng/ml; p = 0.002). At 5 years, the event rate was higher in the high-sLR11 group than in the normal-sLR11 group. The high-sLR11 group showed 5 hospitalizations due to HF (25.0%) and 2 deaths (10.0%), whereas the normal-sLR11 group showed no hospitalizations or deaths. Analyses using receiver operating characteristic curves showed a higher area under the concentration-time curve (AUC) for sLR11 level (AUC = 0.85; 95% confidence interval (CI) = 0.72-0.98) than for BNP (AUC = 0.80, 95%CI = 0.62-0.99) in the diagnosis of PH in left heart disease.CONCLUSIONS:Concentration of sLR11 is associated with severity of PH and offers a strong predictor of severe mitral regurgitation in patients after surgery.

Introduction: Pulmonary hypertension caused by left heart disease (PH-LHD) was classified WHO Group 2 PH. PH-LHD occurs pulmonary vascular remodeling and combined post- and pre-capillary PH (Cpc-PH). PH-LHD is poor prognosis than without PH. LR11 (low-density lipoprotein receptor with 11 binding repeats) is involved in vascular smooth muscle cell migration and proliferation, exacerbate pulmonary arterial hypertension in mice model. But whether sLR11(soluble LR11) associates with PH-LHD has not been clarified. This study examined whether sLR11 level correlates with the severity of PH-LHD and useful for biomarker. Methods: We designed to retrospective observational study, enrolled 38 mitral regurgitation patients who were scheduled mitral valve repair or replacement and underwent right heart catheterization from January 2008 to December 2009. We collected blood samples and measured sLR11, investigated to correlate with each pulmonary hemodynamic value. Results: In PH-LHD group (n=13, mPAP≥25 mmHg) are significantly higher Serum sLR11 levels than without PH ( 14.4±1.1 vs 9.9±0.8ng/ml; P=0.002, respectively). sLR11 levels were associated with mPAP (mean pulmonary arterial pressure) (r=0.9, p<0.001), TPG (transpulmonary gradient) (r=0.37, p=0.02) and PVR (pulmonary vascular resistance) (r=0.14, p<0.05). Furthermore we found high sLR11 concentration (>9.4ng/ml) was associated with mortality. Conclusions: We found sLR11 levels associates with mPAP, TPG and PVR. sLR11 is a useful marker to prognosis in PH-LHD.

Introduction: Pulmonary hypertension (PH) is a syndrome of increased pulmonary artery pressure and often leads to death. Left heart diseases(LHD) are frequently complicated by PH (PH-LHD), classified group2. In particular, PH with heart failure with preserved LV ejection fraction (HFpEF) is higher prevalence metabolic syndrome and poor prognosis than LHD without PH. Tofogliflozin (TOFO) is SGLT2 inhibitor as a therapeutic agent for diabetes. Recent study revealed SGLT2 inhibitors have a beneficial effect on heart failure. However it has not been clarified that SGLT2 inhibitors affect PH-LHD. This study examined whether TOFO improved for PH-LHD. Hypothesis: We hypothesis TOFO has a protective effect for PH with HFpEF. Methods: We used two HFpEF mice models, induced by transverse aortic constriction (TAC) surgery and high fat diet (HFD). TAC model: C57BL/6J mice were subjected to TAC. Sham and TAC mice were treated with TOFO 3mg/kg in water by day or only water. After 4weeks, each mouse was measured physical data, Body weight (BW), Left ventricular weight (LV), Right ventricular weight (RV), right ventricular systolic pressure (RVSP), UCG, collected blood and urine glucose. HFD model: AKR/J mice fed a HFD for 20weeks. Regular diet and HFD mice were treated with TOHO 3mg/kg in water by day or only water. 20weeks later each mouse measured above data. Results and Conclusions: Mice treated with TOFO had significantly higher urine glucose concentrations. TAC induced left ventricular hypertrophy, increased HW/BW ratio and RVSP. However TAC+TOFO mice were reduced hypertrophy and LV/BW ratio than TAC group. Moreover TAC+TOFO mice were improved RV/LV ratio and RVSP (Figure). AKR/J+HFD groups substantially higher BW and occurred PH than RFD groups. In contrast with HFD, TOFO treated group ameliorated BW, RW/LW ratio, moreover normal RVSP. These results showed Tofogliflozin had a beneficial effect for PH with HFpEF.

OBJECTIVES:Follistatin-like 1 (FSTL1) is a glycoprotein secreted by skeletal muscle cells and cardiac myocytes. Previous studies showed that serum FSTL1 concentrations were increased in acute coronary syndrome and chronic heart failure. The aim of this study was to assess the associations among plasma FSTL1 concentration, clinical parameters, and whether FSTL1 concentration could predict cardiovascular events in patients with elective percutaneous coronary intervention (PCI). METHODS AND RESULTS:A consecutive series of 410 patients who underwent elective PCI with drug-eluting stents (DES) were enrolled between August 2004 and December 2006 at Juntendo University hospital. We measured plasma FSTL1 levels prior to elective PCI and assessed the association among FSTL1 levels, clinical parameters, and occurrence of major adverse cardiac or cerebrovascular events (MACCE) defined as cardiac death, nonfatal myocardial infarction, unstable angina, stroke, and hospitalization for heart failure. FSTL1 concentration was positively correlated with high-sensitivity C-reactive protein (hsCRP), serum creatinine, and N-terminal pro b-type natriuretic peptide (all P < 0.01). After excluding patients with creatinine clearance < 60 mL/min and hsCRP ≥ 0.2 mg/dL, the remaining 214 were followed for a median of 5.1 years. Twenty (9.3%) patients experienced MACCE. Receiver operating characteristics curve analysis estimated an FSTL1 cutoff of 41.1 ng/mL to predict MACCE occurrence. Kaplan-Meier analysis found a higher MACCE rate in patients with high (≥ 41.1 ng/mL) than with low (< 41.1 ng/mL) FSTL1 (P < 0.01). Multivariate Cox hazard analysis found that high FSTL1 was an independent predictor of MACCE (hazard ratio 4.54, 95% confidence interval: 1.45-20.07, P < 0.01). CONCLUSION:High plasma FSTL1 may be a predictor of cardiovascular events in patients who underwent elective PCI with DES, especially with preserved renal function and low hsCRP.

Introduction: Pulmonary hypertension due to left heart disease (PH-LHD) progresses to combined post- and pre-capillary PH (Cpc-PH) which is associated with pulmonary vascular remodeling. LR11 (low-...

RATIONALE:Physical exercise provides benefits for various organ systems, and some of systemic effects of exercise are mediated through modulation of muscle-derived secreted factors, also known as myokines. Myonectin/C1q (complement component 1q)/TNF (tumor necrosis factor)-related protein 15/erythroferrone is a myokine that is upregulated in skeletal muscle and blood by exercise.OBJECTIVE:We investigated the role of myonectin in myocardial ischemic injury.METHODS AND RESULTS:Ischemia-reperfusion in myonectin-knockout mice led to enhancement of myocardial infarct size, cardiac dysfunction, apoptosis, and proinflammatory gene expression compared with wild-type mice. Conversely, transgenic overexpression of myonectin in skeletal muscle reduced myocardial damage after ischemia-reperfusion. Treadmill exercise increased circulating myonectin levels in wild-type mice, and it reduced infarct size after ischemia-reperfusion in wild-type mice, but not in myonectin-knockout mice. Treatment of cultured cardiomyocytes with myonectin protein attenuated hypoxia/reoxygenation-induced apoptosis via S1P (sphingosine-1-phosphate)-dependent activation of cAMP/Akt cascades. Similarly, myonectin suppressed inflammatory response to lipopolysaccharide in cultured macrophages through the S1P/cAMP/Akt-dependent signaling pathway. Moreover, blockade of S1P-dependent pathway reversed myonectin-mediated reduction of myocardial infarct size in mice after ischemia-reperfusion.CONCLUSIONS:These data indicate that myonectin functions as an endurance exercise-induced myokine which ameliorates acute myocardial ischemic injury by suppressing apoptosis and inflammation in the heart, suggesting that myonectin mediates some of the beneficial actions of exercise on cardiovascular health.

Ischemic heart disease is one of the leading causes of death. Fibroblast growth factor 21 (FGF21) is a circulating factor with an anti-diabetic property. Skeletal muscle is an important source of FGF21 production. Here, we investigated whether skeletal muscle-derived FGF21 modulates cardiac remodeling in a murine model of myocardial infarction. Myocardial infarction was produced in C57BL/6J wild-type (WT) mice by the permanent ligation of the left anterior descending coronary artery (LAD). Adenoviral vectors expressing FGF21 (Ad-FGF21) or control β-galactosidase were intramuscularly injected into mice at 3 days before permanent LAD ligation. Intramuscular injection of Ad-FGF21 increased plasma FGF21 levels in WT mice compared with control. Treatment of WT mice with Ad-FGF21 led to improvement of left ventricular systolic dysfunction and dilatation at 2 weeks after LAD ligation. Ad-FGF21 administration to WT mice also led to enhancement of capillary density in the infarct border zone, and reduction of myocyte apoptosis in the remote zone, which were accompanied by decreased expression of pro-inflammatory cytokines. Furthermore, treatment of WT mice with Ad-FGF21 increased plasma levels of adiponectin, which is a cardioprotective adipokine. The beneficial effects of Ad-FGF21 on cardiac dysfunction and inflammatory response after myocardial infarction were diminished in adiponectin-knockout mice. These data suggest that muscle-derived FGF21 ameliorates adverse cardiac remodeling after myocardial infarction, at least in part, through an adiponectin-dependent mechanism.

Heart disease contributes to the progression of CKD. Heart tissue produces a number of secreted proteins, also known as cardiokines, which participate in intercellular and intertissue communication. We recently reported that follistatin-like 1 (Fstl1) functions as a cardiokine with cardioprotective properties. Here, we investigated the role of cardiac Fstl1 in renal injury after subtotal nephrectomy. Cardiac-specific Fstl1-deficient (cFstl1-KO) mice and wild-type mice were subjected to subtotal (5/6) nephrectomy. cFstl1-KO mice showed exacerbation of urinary albumin excretion, glomerular hypertrophy, and tubulointerstitial fibrosis after subtotal renal ablation compared with wild-type mice. cFstl1-KO mice also exhibited increased mRNA levels of proinflammatory cytokines, including TNF-α and IL-6, NADPH oxidase components, and fibrotic mediators, in the remnant kidney. Conversely, systemic administration of adenoviral vectors expressing Fstl1 (Ad-Fstl1) to wild-type mice with subtotal nephrectomy led to amelioration of albuminuria, glomerular hypertrophy, and tubulointerstitial fibrosis, accompanied by reduced expression of proinflammatory mediators, NADPH oxidase components, and fibrotic markers in the remnant kidney. In cultured human mesangial cells, treatment with recombinant FSTL1 attenuated TNF-α-stimulated expression of proinflammatory cytokines. Treatment of mesangial cells with FSTL1 augmented the phosphorylation of AMP-activated protein kinase (AMPK), and inhibition of AMPK activation abrogated the anti-inflammatory effects of FSTL1. These data suggest that Fstl1 functions in cardiorenal communication and that the lack of Fstl1 production by myocytes promotes glomerular and tubulointerstitial damage in the kidney.

Obesity is highly linked with the development of vascular diseases. Omentin is a circulating adipokine that is downregulated in patients with cardiovascular diseases. In this study, we investigated the role of omentin in regulation of vascular remodeling in response to injury. Wild-type (WT) mice were treated intravenously with adenoviral vectors encoding human omentin (Ad-OMT) or control beta-gal and subjected to arterial wire injury. Ad-OMT treatment reduced the neointimal thickening and the frequencies of bromodeoxyuridine-positive proliferating cells in injured arteries. Treatment of vascular smooth muscle cells (VSMCs) with human omentin protein at a physiologic concentration led to suppression of growth and ERK phosphorylation after stimulation with various growth factors. Omentin stimulated AMPK signaling in VSMCs, and blockade of AMPK reversed omentin-mediated inhibition of VSMC growth and ERK phosphorylation. Furthermore, fat-specific human omentin transgenic (OMT-TG) mice exhibited reduced neointimal thickening and vascular cell growth following vascular injury. AMPK activation was enhanced in injured arteries in OMT-TG mice, and administration of AMPK inhibitor reversed the reduction of neointimal hyperplasia in OMT-TG mice. These data indicate that omentin attenuates neointimal formation after arterial injury and suppresses VSMC growth through AMPK-dependent mechanisms. Thus, omentin can represent a novel target molecule for the prevention of vascular disorders.

Background— Myocardial infarction (MI) is one of the major causes of death worldwide. Chronic heart failure is a serious complication of MI that leads to poor prognosis. We recently found that neuron-derived neurotrophic factor (NDNF) is a proangiogenic secretory protein that is upregulated in ischemic skeletal muscle. Here, we examined whether NDNF modulates cardiac remodeling in response to chronic ischemia. Methods and Results— C57BL/6J wild-type mice were subjected to the permanent ligation of the left anterior descending coronary artery to create MI. Adenoviral vectors expressing NDNF or β-galactosidase (control) were intramuscularly injected into mice 3 days before permanent left anterior descending coronary artery ligation. Intramuscular administration of adenoviral vectors expressing NDNF to mice resulted in increased levels of circulating NDNF. Adenoviral vectors expressing NDNF administration improved left ventricular systolic dysfunction and dilatation after MI surgery. Moreover, adenoviral vectors expressing NDNF enhanced capillary formation and reduced cardiomyocyte apoptosis and hypertrophy in the post-MI hearts. Treatment of cultured cardiomyocytes with recombinant NDNF protein led to reduced apoptosis under conditions of hypoxia. NDNF also promoted the phosphorylation of Akt and focal adhesion kinase in cardiomyocytes. Blockade of focal adhesion kinase activation blocked the stimulatory effects of NDNF on cardiomyocyte survival and Akt phosphorylation. Similarly, treatment of cultured endothelial cells with NDNF protein led to enhancement of network formation and Akt phosphorylation, which was diminished by focal adhesion kinase inhibition. Conclusions— These data suggest that NDNF ameliorates adverse myocardial remodeling after MI by its abilities to enhance myocyte survival and angiogenesis in the heart through focal adhesion kinase/Akt-dependent mechanisms.

Objective: Cardiovascular disease is one of the leading causes of death worldwide. Regular exercise is associated with a cardiovascular risk reduction. Fibroblast growth factor 21 (FGF21) is secreted from skeletal muscle and upregulated by exercise training. Here, we investigated whether skeletal muscle-derived FGF21 affects cardiac remodeling in mice following myocardial infarction.Methods and Results: C57BL/6J wild-type (WT) mice were subjected to myocardial infarction by permanent ligation of the left anterior descending coronary artery (LAD). Mice were intramuscularly treated with an adenoviral vector encoding FGF21 (Ad-FGF21) or control β-galactosidase (Ad-β-gal) at 3 days before LAD ligation. Intramuscular treatment of WT mice with Ad-FGF21 increased plasma levels of FGF21 compared with Ad-β-gal. At 2 weeks after LAD ligation, Ad-FGF21-treated WT mice exhibited improvement of left ventricular systolic function and chamber size, and reduction of myocyte hypertrophy compared to Ad-β-gal-treated mice. Administration of Ad-FGF21 to WT mice also increased capillary density in the infarct border zone as evaluated by CD31 immunostaining and reduced cardiomyocyte apoptosis in the remote zone as assessed by TUNEL staining. In addition, Ad-FGF21 decreased mRNA levels of pro-inflammatory cytokines and fibrotic mediators in the heart of WT mice after myocardial infarction. Moreover, treatment of WT mice with Ad-FGF21 increased plasma levels of a cardioprotective adipokine adiponectin. Of note, intramuscular injection of Ad-FGF21 failed to improve cardiac function and dilatation in adiponectin-deficient mice after myocardial infarctionConclusions: These data suggest that muscle-derived FGF21 prevents adverse cardiac remodeling after myocardial infarction by its abilities to modulate myocyte hypertrophy and apoptosis, inflammation and angiogenesis in the heart and that adiponectin plays an important role in the cardioprotective action of FGF21.

It is well-established that exercise diminishes cardiovascular risk, but whether humoral factors secreted by muscle confer these benefits has not been conclusively shown. We have shown that the secreted protein follistatin-like 1 (Fstl1) has beneficial actions on cardiac and endothelial function. However, the role of muscle-derived Fstl1 in proliferative vascular disease remains largely unknown. Here, we investigated whether muscle-derived Fstl1 modulates vascular remodelling in response to injury.The targeted ablation of Fstl1 in muscle led to an increase in neointimal formation following wire-induced arterial injury compared with control mice. Conversely, muscle-specific Fstl1 transgenic (TG) mice displayed a decrease in the neointimal thickening following arterial injury. Muscle-specific Fstl1 ablation and overexpression increased and decreased, respectively, the frequency of BrdU-positive proliferating cells in injured vessels. In cultured human aortic smooth muscle cells (HASMCs), treatment with human FSTL1 protein decreased proliferation and migration induced by stimulation with PDGF-BB. Treatment with FSTL1 enhanced AMPK phosphorylation, and inhibition of AMPK abrogated the inhibitory actions of FSTL1 on HASMC responses to PDGF-BB. The injured arteries of Fstl1-TG mice exhibited an increase in AMPK phosphorylation, and administration of AMPK inhibitor reversed the anti-proliferative actions of Fstl1 on the vessel wall.Our findings indicate that muscle-derived Fstl1 attenuates neointimal formation in response to arterial injury by suppressing SMC proliferation through an AMPK-dependent mechanism. Thus, the release of protein factors from muscle, such as Fstl1, may partly explain why the maintenance of muscle function can have a therapeutic effect on the cardiovascular system.

Background: Tissue ischemia stimulates production of secreted factors that regulate angiogenesis. Results: Neuron-derived neurotrophic factor (NDNF) is up-regulated in endothelial cells in ischemic limbs of mice. NDNF stimulates endothelial cell function and promotes ischemia-induced revascularization through NOS-dependent mechanisms. Conclusion: NDNF functions as a novel modulator that stimulates revascularization processes. Significance: NDNF represents a novel therapeutic target for ischemic vascular diseases.Strategies to stimulate revascularization are valuable for cardiovascular diseases. Here we identify neuron-derived neurotrophic factor (NDNF)/epidermacan as a secreted molecule that is up-regulated in endothelial cells in ischemic limbs of mice. NDNF was secreted from cultured human endothelial cells, and its secretion was stimulated by hypoxia. NDNF promoted endothelial cell network formation and survival in vitro through activation of Akt/endothelial NOS (eNOS) signaling involving integrin v3. Conversely, siRNA-mediated knockdown of NDNF in endothelial cells led to reduction of cellular responses and basal Akt signaling. Intramuscular overexpression of NDNF led to enhanced blood flow recovery and capillary density in ischemic limbs of mice, which was accompanied by enhanced phosphorylation of Akt and eNOS. The stimulatory actions of NDNF on perfusion recovery in ischemic muscles of mice were abolished by eNOS deficiency or NOS inhibition. Furthermore, siRNA-mediated reduction of NDNF in muscles of mice resulted in reduction of perfusion recovery and phosphorylation of Akt and eNOS in response to ischemia. Our data indicate that NDNF acts as an endogenous modulator that promotes endothelial cell function and ischemia-induced revascularization through eNOS-dependent mechanisms. Thus, NDNF can represent a therapeutic target for the manipulation of ischemic vascular disorders.