Long-Term Follow-up Study of Hospitalizations for Acute Coronary Syndrome in Kobe-City and Other Districts Under the Hyogo Smoking Ban Legislation　- A Nationwide Database Study.

BACKGROUND: Hyogo Prefecture has managed smoking ban legislation with partial restrictions in public places (Hyogo-L) since 2013. Previous studies have reported a significant decrease in admissions for acute coronary syndrome (ACS) in Kobe-city, but not in other districts of Hyogo Prefecture in the 2 years after Hyogo-L. The aim of the present study was to define the long-term effect of Hyogo-L.Methods and Results: The JROAD-DPC dataset was used to collect information on the number of hospitalizations for ACS in Hyogo Prefecture, and in Osaka-city without smoking ban legislation, from April 2013 to March 2020. Poisson regression analysis was performed to calculate incident rate ratios (IRRs) and 95% confidence intervals (CIs). ACS records of 3,101 in Kobe-city, 11,375 in areas of Hyogo Prefecture other than Kobe-city and 11,079 in Osaka-city were collected for admissions. The incidence of ACS reduced significantly over time in Kobe-city [IRR (95% CI); 0.96 (0.94-0.97)], but did not reduce in the others. The decrease in Kobe-city was observed in ACS patients without smoking, hypertension, and hyperlipidemia, but not in those with such risk factors. CONCLUSIONS: The long-term ACS reduction or non-reduction under Hyogo-L was determined at the initial period and the same scenario continued, supporting the importance of legislation and compliance with the smoking ban. The lowering effect was remarkable in ACS patients without risk factors such as non-smoking.

Anti-apoptosis in nonmyocytes and pro-autophagy in cardiomyocytes: two strategies against postinfarction heart failure through regulation of cell death/degeneration.

Anti-apoptotic therapy for cardiomyocytes could be an effective strategy for preventing or treating heart failure. Notably, however, morphological evidence definitively demonstrating cardiomyocyte apoptosis has been very rare in actual heart diseases such as acute myocardial infarction and heart failure. By contrast, within the postinfarction heart, interstitial noncardiomyocytes such as granulation tissue cells do die via apoptosis to form scar tissue. Blockade of this apoptosis improves survival and mitigates ventricular remodeling and dysfunction during the chronic stage. Possible mechanisms to explain this benefit might be preservation of infarcted wall thickness and preservation of myofibroblasts, which could promote infarct shrinkage; both would reduce wall stress through Laplace's law. On the other hand, autophagy is an intracellular degradation mechanism that compensates for energy insufficiency by digesting and recycling intracellular components, and is often observed in cardiomyocytes within failing hearts with various origins including postinfarction. Starvation strongly induces and activates autophagic degeneration within cardiomyocytes. When that activation is inhibited, the starved animals suffer from heart failure. Promoting autophagy through caloric restriction or several reagents not only reduces the acute infarct size but also mitigates postinfarction cardiac remodeling and dysfunction during chronic stages. Moreover, augmenting autophagy by the treatment with resveratrol or exercise can bring about reverse remodeling in failing hearts with a large old myocardial infarction. In conclusion, we propose two strategies for managing postinfarction heart failure through control of cell death/degeneration: (1) anti-apoptosis in granulation tissue noncardiomyocytes; and (2) pro-autophagy in salvaged cardiomyocytes.

Survey on the Status of Smoking Inside Eating Establishments in the Cities of Kobe and Amagasaki.

BACKGROUND: The Hyogo Prefectural Government has been enforcing a smoking ban ordinance since April 2013. The present survey was conducted to determine the extent to which the smoking ban has been successfully implemented in eating establishments in Kobe City and Amagasaki City.Methods and Results:The Health and Welfare Department of the Hyogo Prefectural Government provided a list of eating establishments in Kobe and Amagasaki City. From these, we chose 1,300 from each city using random number generation. Responses were obtained from 310 establishments in Kobe City (response rate: 23.8%) and 297 in Amagasaki City (22.8%). Overall, 58.1% of the establishments surveyed in Kobe City were aware of the ordinance, a recognition rate significantly higher than that of Amagasaki City, where only 45.5% of eateries were aware of the ordinance (P=0.003). Of the Kobe City eateries, 31.7% had succeeded in implementing a complete ban on smoking. In Amagasaki City, the rate was significantly lower, at just 13.4% (P<0.001). A logistic regression analysis showed that coffee shops, Japanese-style taverns, bars, and eating establishments that served alcohol were the independent significant predictors of low compliance. Kobe City restaurants, women, and families were the independent significant predictors of high compliance with the complete smoking ban. CONCLUSIONS: The rates of recognition and implementation of the complete smoking ban were significantly lower in Amagasaki City than in Kobe City. There needs to be a strong and continuous socialization campaign to promote the ordinance.

Effects of Ezetimibe-Statin Combination Therapy on Coronary Atherosclerosis in Acute Coronary Syndrome.

BACKGROUND: The results of previous clinical trials on the effects of ezetimibe-statin combination therapy on atherosclerosis are inconsistent, and the anti-atherosclerotic effect of ezetimibe remains controversial.Methods and Results:We conducted a prospective, randomized open-label study at 10 centers. One hundred and twenty-eight statin-naïve patients with acute coronary syndrome (ACS) undergoing intravascular ultrasound (IVUS)-guided percutaneous coronary intervention were randomized to receive either 2 mg/day pitavastatin plus 10 mg/day ezetimibe, or 2 mg/day pitavastatin. One hundred and 3 patients had evaluable IVUS of non-culprit coronary lesions at baseline and at follow-up. The primary endpoint was the percentage change in non-culprit coronary plaque volume (PV) and lipid PV on integrated backscatter IVUS. Mean low-density lipoprotein cholesterol was reduced from 123 mg/dL to 64 mg/dL in the combination therapy group (n=50) and 126 mg/dL to 87 mg/dL in the statin alone group (n=53; between-group difference, 16.9%, P<0.0001). The percent change in PV was -5.1% in the combination therapy group and -6.2% in the statin alone group (P=0.66), although both groups had reduction of PV compared with baseline (both P<0.01). The percent change in lipid PV did not differ between the groups (4.3 vs. -3.0%, P=0.37). CONCLUSIONS: In statin-naïve patients with ACS, combined therapy with ezetimibe and statin did not result in a significant change in coronary plaque regression or tissue component compared with statin alone. [Clinical Trial Registration: www.clinicaltrials.gov (NCT00549926)].

Results of a Prospective Study of Acute Coronary Syndrome Hospitalization After Enactment of a Smoking Ban in Public Places in Hyogo Prefecture　- Comparison With Gifu, a Prefecture Without a Public Smoking Ban.

BACKGROUND: Hyogo Prefecture is the 2nd prefecture in Japan, after Kanagawa, to enact a ban with penal code on smoking in public places, although the restriction is partial.Methods and Results:This study included consecutive patients with acute coronary syndrome (ACS) who were admitted to 33 major hospitals in the Hyogo District during the 12 months before implementation of the legislation and during the 24 months thereafter. Consecutive patients with ACS from Gifu Prefecture who were admitted to 20 major hospitals were enrolled as geographical controls. The number of ACS admissions did not change from the years 2012-2015 in both Hyogo District (1,774 in the pre-year, 1,784 in the 1st year, and 1,720 in the 2nd year) and Gifu Prefecture (1,226 in the pre-year, 1,174 in the 1st year, and 1,206 in the 2nd year). However, a clear reduction was observed in the subanalysis for Kobe City (895 in the preceding year, 830 (-7.3%) in the 1st year, and 792 (-11.5%) in the 2nd year), where adherence to the smoking ban was higher than in other Hyogo districts. CONCLUSIONS: The primary endpoint did not show a significant change. However, the subanalysis showed a significant decrease in ACS admissions in Kobe City. These results suggest that ACS reduction may depend on the degree of adherence to a smoking ban. (Circ J 2016; 80: 2528-2532).

Feasibility of tissue characterization of coronary plaques using 320-detector row computed tomography: comparison with integrated backscatter intravascular ultrasound.

Recently, a new generation of multi-detector row computed tomography (CT) with 320-detector rows (DR) has become available in the clinical settings. The purpose of the present study was to determine the cutoff values of Hounsfield unit (HU) for discrimination of plaque components by comparing HU of coronary plaques with integrated backscatter intravascular ultrasound (IB-IVUS) serving as a gold standard. Seventy-seven coronary atherosclerotic lesions in 77 patients with angina were visualized by both 320-DR CT (Aquilion One, Toshiba, Japan) and IB-IVUS at the same site. To determine the thresholds for discrimination of plaque components, we compared HU with IB values as a gold standard. Optimal thresholds were determined from receiver operating characteristic (ROC) curves analysis. The HU values of lipid pool (n = 115), fibrosis (n = 93), vessel lumen and calcification (n = 73) were 28 ± 19 HU (range -18 to 69 HU), 98 ± 31 HU (44 to 195 HU), 357 ± 65 HU (227 to 534 HU) and 998 ± 236 HU (366 to 1,489 HU), respectively. The thresholds of 56 HU, 210 HU and 490 HU were the most reliable predictors of lipid pool, fibrosis, vessel lumen and calcification, respectively. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS (r = 0.63, p < 0.05), whereas fibrous volume measured by 320-DR CT was not. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS, whereas fibrous volume was not correlated with that measured by IB-IVUS because manual exclusion of the outside of vessel hindered rigorous discrimination between fibrosis and extravascular components.

OPC-28326, a selective peripheral vasodilator with angiogenic activity, mitigates postinfarction cardiac remodeling.

Although OPC-28326, 4-(N-methyl-2-phenylethylamino)-1-(3,5-dimethyl-4-propionyl-aminobenzoyl) piperidine hydrochloride monohydrate, was developed as a selective peripheral vasodilator with α2-adrenergic antagonist properties, it also reportedly exhibits angiogenic activity in an ischemic leg model. The purpose of this study was to examine the effect of OPC-28326 on the architectural dynamics and function of the infarcted left ventricle during the chronic stage of myocardial infarction. Myocardial infarction was induced in male C3H/He mice, after which the mice were randomly assigned into two groups: a control group receiving a normal diet and an OPC group whose diet contained 0.05% OPC-28326. The survival rate among the mice (n = 18 in each group) 4 wk postinfarction was significantly greater in the OPC than control group (83 vs. 44%; P < 0.05), and left ventricular remodeling and dysfunction were significantly mitigated. Histologically, infarct wall thickness was significantly greater in the OPC group, due in part to an abundance of nonmyocyte components, including blood vessels and myofibroblasts. Five days postinfarction, Ki-67-positive proliferating cells were more abundant in the granulation tissue in the OPC group, and there were fewer apoptotic cells. These effects were accompanied by activation of myocardial Akt and endothelial nitric oxide synthase. Hypoxia within the infarct issue, assessed using pimonidazole staining, was markedly attenuated in the OPC group. In summary, OPC-28326 increased the nonmyocyte population in infarct tissue by increasing proliferation and reducing apoptosis, thereby altering the tissue dynamics such that wall stress was reduced, which might have contributed to a mitigation of postinfarction cardiac remodeling and dysfunction.

Restriction of food intake prevents postinfarction heart failure by enhancing autophagy in the surviving cardiomyocytes.

We investigated the effect of restriction of food intake, a potent inducer of autophagy, on postinfarction cardiac remodeling and dysfunction. Myocardial infarction was induced in mice by left coronary artery ligation. At 1 week after infarction, mice were randomly divided into four groups: the control group was fed ad libitum (100%); the food restriction (FR) groups were fed 80%, 60%, or 40% of the mean amount of food consumed by the control mice. After 2 weeks on the respective diets, left ventricular dilatation and hypofunction were apparent in the control group, but both parameters were significantly mitigated in the FR groups, with the 60% FR group showing the strongest therapeutic effect. Cardiomyocyte autophagy was strongly activated in the FR groups, as indicated by up-regulation of microtubule-associated protein 1 light chain 3-II, autophagosome formation, and myocardial ATP content. Chloroquine, an autophagy inhibitor, completely canceled the therapeutic effect of FR. This negative effect was associated with reduced activation of AMP-activated protein kinase and of ULK1 (a homolog of yeast Atg1), both of which were enhanced in hearts from the FR group. In vitro, the AMP-activated protein kinase inhibitor compound C suppressed glucose depletion-induced autophagy in cardiomyocytes, but did not influence activity of chloroquine. Our findings imply that a dietary protocol with FR could be a preventive strategy against postinfarction heart failure.

Resveratrol reverses remodeling in hearts with large, old myocardial infarctions through enhanced autophagy-activating AMP kinase pathway.

We investigated the effect of resveratrol, a popular natural polyphenolic compound with antioxidant and proautophagic actions, on postinfarction heart failure. Myocardial infarction was induced in mice by left coronary artery ligation. Four weeks postinfarction, when heart failure was established, the surviving mice were started on 2-week treatments with one of the following: vehicle, low- or high-dose resveratrol (5 or 50 mg/kg/day, respectively), chloroquine (an autophagy inhibitor), or high-dose resveratrol plus chloroquine. High-dose resveratrol partially reversed left ventricular dilation (reverse remodeling) and significantly improved cardiac function. Autophagy was augmented in those hearts, as indicated by up-regulation of myocardial microtubule-associated protein-1 light chain 3-II, ATP content, and autophagic vacuoles. The activities of AMP-activated protein kinase and silent information regulator-1 were enhanced in hearts treated with resveratrol, whereas Akt activity and manganese superoxide dismutase expression were unchanged, and the activities of mammalian target of rapamycin and p70 S6 kinase were suppressed. Chloroquine elicited opposite results, including exacerbation of cardiac remodeling associated with a reduction in autophagic activity. When resveratrol and chloroquine were administered together, the effects offset one another. In vitro, compound C (AMP-activated protein kinase inhibitor) suppressed resveratrol-induced autophagy in cardiomyocytes, but did not affect the events evoked by chloroquine. In conclusion, resveratrol is a beneficial pharmacological tool that augments autophagy to bring about reverse remodeling in the postinfarction heart.

Regression of Electrocardiographic Signs of Left Ventricular Hypertrophy by Combined Treatment With Thiazide Diuretic and Angiotensin-II Receptor Blocker.

BACKGROUND: In hypertensive patients, left ventricular hypertrophy (LVH) may persist despite satisfactory blood pressure (BP) control. The efficacy of thiazide diuretics in Western countries has been reported, but whether this applies to hypertensive Japanese patients is uncertain. METHODS AND RESULTS: We randomly assigned 94 patients whose BP was poorly controlled with usual doses of angiotensin-II receptor blockers (ARB), to losartan/hydrochlorothiazide (HCTZ) fixed-dose combination vs. maximum doses of ARB. After 6 months follow-up, decrease in BP, regression of electrocardiographic LVH, and changes in laboratory measurements were examined. Although a similar decrease in BP was observed in both groups, the decrease in LV Sokolow-Lyon voltage, from 34.4±9.2 to 29.4±8.8 mm in the losartan/HCTZ vs. from 29.9±10.2 to 29.1±8.4 mm in the ARB group (P=0.0003), and the decrease in serum B-type natriuretic peptide (BNP) level, from 30.1±28.5 to 26.8±28.0 pg/ml vs. from 23.7±14.8 to 29.8±29.3 pg/ml (P=0.045) were greater in the losartan/HCTZ group. By single variable logistic regression analysis, ∆BNP (P=0.012) and treatment with losartan/HCTZ (P<0.0001) correlated with the regression of LVH. By multiple variable logistic regression analysis, both ∆BNP (P=0.035) and treatment with losartan/HCTZ (P=0.0003) remained significant. No major adverse effects were observed. CONCLUSIONS: Greater regression of LVH was safely achieved with losartan/HCTZ in patients whose BP was poorly controlled with an ARB.

Postinfarct active cardiac-targeted delivery of erythropoietin by liposomes with sialyl Lewis X repairs infarcted myocardium in rabbits.

We investigated the effect of cardiac-targeting erythropoietin (EPO)-encapsulated liposomes with sialyl Lewis(X) (SLX) on myocardial infarct (MI) size, left ventricular (LV) remodeling and function, and its molecular mechanism for repairing infarcted myocardium. In rabbits, MI was induced by 30 min of coronary occlusion followed by reperfusion. EPO-encapsulated liposomes with SLX (L-EPO group), EPO-encapsulated liposomes without SLX (L-EPO without SLX group), liposomes with SLX without EPO (L group), or saline (saline group) were intravenously administered immediately after MI. MI sizes and numbers of microvessels were assessed 14 days after MI. Prosurvival proteins and signals were assessed by Western blot analysis 2 and 14 days after MI. Confocal microscopy and electron microscopy showed the specific accumulation of liposomes with SLX in the infarcted myocardium. MI and cardiac fibrosis areas were significantly smaller in the L-EPO group than in the other groups. LV function and remodeling were improved in the L-EPO group. The number of CD31-positive microvessels was significantly greater in the L-EPO group than in the other groups. Higher expressions of EPO receptors, phosphorylated (p)Akt, pERK, pStat3, VEGF, Bcl-2, and promatrix metalloproteinase-1 were observed in the infarct area in the L-EPO group than in the other groups. EPO-encapsulated liposomes with SLX selectively accumulated in the infarct area, reduced MI size, and improved LV remodeling and function through activation of prosurvival signals and by exerting antifibrotic and angiogenic effects. EPO-encapsulated liposomes with SLX may be a promising strategy for active targeting treatment of acute MI.

Tetomilast attenuates elastase-induced pulmonary emphysema through inhibition of oxidative stress in rabbits.

Tetomilast was originally identified as a potent inhibitor of superoxide production in human neutrophils, and is of interest because it may relieve oxidative stress related to chronic obstructive pulmonary disease (COPD). Our objective was to determine whether tetomilast effectively protects against the development of porcine pancreatic elastase (PPE)-induced emphysema in rabbits. Rabbits were divided into three groups (sham n=19, PPE n=19, PPE/Tetomilast n=18). The rabbits were once daily orally administered vehicle solution or tetomilast 5 d/week for 4 weeks before the PPE instillation. We compared pulmonary function, inflammatory cell infiltration, oxidative stress, and the incidences of apoptosis among the three groups. Tetomilast suppressed PPE-induced increases in the incidence of apoptosis and the production of 8-hydroxy-deoxyguanosine (8-OHdG) in lung tissues. PPE-instilled rabbits treated with tetomilast showed significantly less mean linear intercept and significantly better pulmonary function than rabbits administered PPE alone. Tetomilast may inhibit the development of emphysema by attenuating pulmonary inflammation and apoptosis caused by PPE-induced oxidative stress.

Comparison between integrated backscatter intravascular ultrasound and 64-slice multi-detector row computed tomography for tissue characterization and volumetric assessment of coronary plaques.

BACKGROUND: The purpose of this study was to determine the cut-off values of Hounsfield units (HU) for the discrimination of plaque components and to evaluate the feasibility of measurement of the volume of plaque components using multi-detector row computed tomography (MDCT). METHODS: Coronary lesions (125 lesions in 125 patients) were visualized by both integrated backscatter intravascular ultrasound (IB-IVUS) and 64-slice MDCT at the same site. The IB values were used as a gold standard to determine the cut off values of HU for the discrimination of plaque components. RESULTS: Plaques were classified as lipid pool (n =50), fibrosis (n =65) or calcification (n =35) by IB-IVUS. The HU of lipid pool, fibrosis and calcification were 18 ± 18 HU (-19 to 58 HU), 95 ± 24 HU (46 to 154 HU) and 378 ± 99 HU (188 to 605 HU), respectively. Using receiver operating characteristic curve analysis, a threshold of 50 HU was the optimal cutoff values to discriminate lipid pool from fibrosis. Lipid volume measured by MDCT was correlated with that measured by IB-IVUS (r =0.66, p <0.001), whereas fibrous volume was not (r =0.21, p =0.059). CONCLUSION: Lipid volume measured by MDCT was moderately correlated with that measured by IB-IVUS. MDCT may be useful for volumetric assessment of the lipid volume of coronary plaques, whereas the assessment of fibrosis volume was unstable.

Relationship among coronary plaque compliance, coronary risk factors and tissue characteristics evaluated by integrated backscatter intravascular ultrasound.

BACKGROUND: The purpose of the present study was to evaluate the mechanical properties of coronary plaques and plaque behavior, and to elucidate the relationship among tissue characteristics of coronary plaques, mechanical properties and coronary risk factors using integrated backscatter intravascular ultrasound (IB-IVUS). METHODS: Non-targeted plaques with moderate stenosis (plaque burden at the minimal lumen site: 50-70%) located proximal to the site of the percutaneous coronary intervention target lesions were evaluated by IB-IVUS. Thirty-six plaques (less calcified group: an arc of calcification ≤10°) in 36 patients and 22 plaques (moderately calcified group: 10° < an arc of calcification ≤60°) in 22 patients were evaluated. External elastic membrane volume (EEMV) compliance, lumen volume (LV) compliance, plaque volume (PV) response (difference between PV in systole and diastole), EEM area stiffness index were measured at the minimal lumen site. Relative lipid volume (lipid volume/internal elastic membrane volume) was calculated by IB-IVUS. RESULTS: In the less calcified group, there was a significant correlation between EEMV compliance and the relative lipid volume (r = 0.456, p = 0.005). There was a significant inverse correlation between EEM area stiffness index and the relative lipid volume (p = 0.032, r = -0.358). The LV compliance and EEM area stiffness index were significantly different in the diabetes mellitus (DM) group than in the non-DM group (1.32 ± 1.49 vs. 2.47 ± 1.79%/10 mmHg, p =0.014 and 28.3 ± 26.0 vs. 15.7 ± 17.2, p =0.020). The EEMV compliance and EEM area stiffness index were significantly different in the hypertension (HTN) group than in the non-HTN group (0.77 ± 0.68 vs. 1.57 ± 0.95%/10 mmHg, p =0.012 and 26.5 ± 24.3 vs. 13.0 ± 16.7, p =0.020). These relationships were not seen in the moderately calcified group. CONCLUSION: The present study provided new findings that there was a significant correlation between mechanical properties and tissue characteristics of coronary arteries. In addition, our results suggested that the EEMV compliance and the LV compliance were independent and the compliance was significantly impaired in the patients with DM and/or HTN. Assessment of coronary mechanical properties during PCI may provide us with useful information regarding the risk stratification of patients with coronary heart disease.

Correlation between serum concentrations of B-type natriuretic peptide and albumin in patients with chronic congestive heart failure.

While B-type natriuretic peptide (BNP) and hypoalbuminemia are both predictors of major adverse cardiac events (MACE) in patients with congestive heart failure (CHF), whether these markers are correlated is not known. We retrospectively analyzed data collected in 85 patients presenting with CHF, a left ventricular (LV) ejection fraction (EF) < 50%, and non-ischemic heart disease, followed for a mean of 38 months. Statistical analysis was performed to 1) examine the relationship between a) baseline BNP or albumin concentrations and b) baseline clinical characteristics, 2) identify the correlates of changes in (Δ) BNP concentrations, and Δ albumin concentrations, and 3) ascertain the prognostic value of each variable. Log transformed BNP was correlated with New York Heart Association functional class, total protein and LVEF, while albumin was correlated with a history of diabetes mellitus and total protein. Δ BNP and Δ albumin concentrations between baseline and follow-up were correlated (P < 0.0001). The follow-up BNP and albumin concentrations were independent predictors of MACE.BNP and albumin were correlated with different baseline clinical characteristics. The long-term changes in the two markers were inversely correlated and both were independent predictors of CHF.

Autophagy limits acute myocardial infarction induced by permanent coronary artery occlusion.

Ischemia is known to potently stimulate autophagy in the heart, which may contribute to cardiomyocyte survival. In vitro, transfection with small interfering RNAs targeting Atg5 or Lamp-2 (an autophagy-related gene necessary, respectively, for the initiation and digestion step of autophagy), which specifically inhibited autophagy, diminished survival among cultured cardiomyocytes subjected to anoxia and significantly reduced their ATP content, confirming an autophagy-mediated protective effect against anoxia. We next examined the dynamics of cardiomyocyte autophagy and the effects of manipulating autophagy during acute myocardial infarction in vivo. Myocardial infarction was induced by permanent ligation of the left coronary artery in green fluorescent protein-microtubule-associated protein 1 light chain 3 (GFP-LC3) transgenic mice in which GFP-LC3 aggregates to be visible in the cytoplasm when autophagy is activated. Autophagy was rapidly (within 30 min after coronary ligation) activated in cardiomyocytes, and autophagic activity was particularly strong in salvaged cardiomyocytes bordering the infarcted area. Treatment with bafilomycin A1, an autophagy inhibitor, significantly increased infarct size (31% expansion) 24 h postinfarction. Interestingly, acute infarct size was significantly reduced (23% reduction) in starved mice showing prominent autophagy before infarction. Treatment with bafilomycin A1 reduced postinfarction myocardial ATP content, whereas starvation increased myocardial levels of amino acids and ATP, and the combined effects of bafilomycin A1 and starvation on acute infarct size offset one another. The present findings suggest that autophagy is an innate and potent process that protects cardiomyocytes from ischemic death during acute myocardial infarction.

Anti-Fas gene therapy prevents doxorubicin-induced acute cardiotoxicity through mechanisms independent of apoptosis.

Activation of Fas signaling is a key mediator of doxorubicin cardiotoxicity, which involves both cardiomyocyte apoptosis and myocardial inflammation. In this study, acute cardiotoxicity was induced in mice by doxorubicin, and some mice simultaneously received an intramuscular injection of adenoviral vector encoding mouse soluble Fas (sFas) gene (Ad.CAG-sFas), an inhibitor of Fas/Fas ligand interaction. Two weeks later, left ventricular dilatation and dysfunction were apparent in the LacZ-treated control group, but both were significantly mitigated in the sFas-treated group. The in situ nick-end labeling-positive rate were similar in the two groups, and although electron microscopy revealed cardiomyocyte degeneration, no apoptotic structural features and no activation of caspases were detected, suggesting an insignificant role of apoptosis in this model. Instead, sFas treatment reversed doxorubicin-induced down-regulation of GATA-4 and attenuated ubiquitination of myosin heavy chain and troponin I to preserve these sarcomeric proteins. In addition, doxorubicin-induced significant leukocyte infiltration, fibrosis, and oxidative damage to the myocardium, all of which were largely reversed by sFas treatment. sFas treatment also suppressed doxorubicin-induced p53 overexpression, phosphorylation of c-Jun N-terminal kinase, c-Jun, and inhibitor of nuclear factor-kappaB, as well as production of cyclooxygenase-2 and monocyte chemoattractant protein-1, and it restored extracellular signal-regulated kinase activation. Therefore, sFas gene therapy prevents the progression of doxorubicin-induced acute cardiotoxicity, with accompanying attenuation of the cardiomyocyte degeneration, inflammation, fibrosis, and oxidative damage caused by Fas signaling.

Treatment of leg ischemia with biodegradable gelatin hydrogel microspheres incorporating granulocyte colony-stimulating factor.

Granulocyte colony-stimulating factor (G-CSF) is a potent angiogenic factor. We hypothesized that G-CSF-immersed gelatin hydrogel microspheres (G-CSF-GHMs) injected into the ischemic legs might continuously release a small amount of G-CSF to locally stimulate angiogenesis without unfavorable systemic effects. Just after ligation of the right femoral artery of BALB/c mice, recombinant human G-CSF (100-µg/kg)-immersed GHM was injected into the right hindlimb muscles; the controls included a saline-injected group, an intramuscularly injected G-CSF group, a subcutaneously injected G-CSG group, and an empty GHM-injected group. Eight weeks later, improvement of blood perfusion to the ischemic limb was significantly augmented in the G-CSF-GHM group compared with any of the control groups. Despite there being no increase in the serum concentration of G-CSF, in peripheral granulocytes, or in circulating endothelial progenitor cells, not only capillary but also arteriolar density was significantly increased in this group. Next, we started treatment with G-CSF-GHM 4 weeks after ligation to examine whether the treatment is effective if performed during the chronic stage of ischemia. The late treatment was also found to effectively improve blood flow in the ischemic leg. In conclusion, G-CSF-GHM administration is suggested to be a promising and readily usable approach to treating peripheral artery disease, applicable even during the chronic stage.