Helicobacter pylori infection and its related factors in junior high school students in Nagano Prefecture, Japan.

BACKGROUND: There have been few reports on Helicobacter pylori (H. pylori) infection in asymptomatic Japanese children and adolescents. We hypothesized that the prevalence of H. pylori infection is very low among Japanese children and that clinical variables such as serum pepsinogen and iron levels are associated with H. pylori infection. MATERIALS AND METHODS: We conducted a cross-sectional analysis of a sample of 454 junior high school students aged 12-15 years in four areas in Nagano Prefecture. A commercial ELISA kit (E-plate Eiken H. pylori antibody) was used to measure IgG antibody against H. pylori. Serum pepsinogen and iron levels were also measured using standard methods. A urea breath test was performed for seropositive students. RESULTS: The overall prevalence of H. pylori was 3.1% (14/454). There were no significant differences in H. pylori prevalence among mountain, rural, and urban areas. The mean level of both serum pepsinogen (PG I) and PG II was significantly increased in the seropositive subjects compared with the seronegative subjects. When the cutoff values for adults (PG I: 70 ng/mL and PG I/II ratio: 3) were used, 4 of 14 subjects had PG I ≤70 ng/mL and PG I/II ratio ≤3. The results of a logistic regression analysis showed that low serum iron levels were significantly associated with H. pylori infection (P=.02). CONCLUSIONS: The prevalence of H. pylori infection is as low as 3% among junior high school students aged 12-15 years in Japan. The disappearance of H. pylori is accelerating in Japanese children.

Importance of cystatin C and uric acid levels in the association of cardiometabolic risk factors in Japanese junior high school students.

BACKGROUND: Serum cystatin C (CysC), a novel marker of renal function, is associated with the components of metabolic syndrome in adults. Little is known about the utility of CysC and its association with cardiometabolic risks in young subjects. METHODS AND RESULTS: In a cohort of 454 Japanese junior high school students, the distribution of serum CysC levels and associated variables were analyzed. CysC levels were significantly higher in boys than in girls (0.92±0.10mg/L vs. 0.77±0.08mg/L, p<0.001). CysC was significantly correlated with serum creatinine (r=0.473, p<0.001), and serum uric acid (SUA) (r=0.546, p<0.001). Multivariable regression analysis revealed significant associations between CysC and SUA in all subjects (ß=0.241, p<0.001), and in boys and girls separately (ß=0.264 and 0.240, respectively, both p<0.001). Importantly, subjects with elevation of both serum CysC and SUA levels had the highest ratio of triglyceride to high-density lipoprotein cholesterol. CONCLUSIONS: CysC had significant associations with both creatinine and SUA in Japanese junior high school students. The concomitant elevation of serum CysC and SUA levels was associated with subclinical lipid metabolism dysregulation, and suggested the presence of cardiometabolic risk accumulation.

Rapid quantitative analysis of human serum sphingomyelin species using MALDI-TOF mass spectrometry with lipid hydrolase treatment.

BACKGROUND: Sphingomyelin (SM) is a key component of extracellular membranes and lipoproteins, and plays roles in cell signaling and as a component of lipoproteins. SM species differ in terms of fatty acid (FA) composition. However, no simple, rapid, quantitative assay for identifying different SM species has yet been reported. In this study, lipid hydrolase treatment and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used to identify serum SM species. METHODS: Sera were collected from healthy young individuals. To identify SM species, sera were treated with phospholipase A2 and lipoprotein lipase, and lipids were extracted using the standard chloroform/methanol (2/1 v/v) method. RESULTS: We detected 15 peaks from serum using MALDI-TOF MS, which were assigned to SM species bound with FA components ranging from C15:0 to C24:2. The most prominent serum SM species was SM [C16:0], which accounted for approximately 26% of serum SM. Some SM species contained an odd-carbon FA (C15, C21, and C23), and these accounted for approximately 4% of serum SM. The reproducibility of major SM species within and between application positions on MS-sample plate was CV=3.0%-7.9% and CV=3.1%-6.8%, respectively. The concentration and dilution ratio were linearly related. The SM species composition of 10 healthy young subjects showed a similar profile. CONCLUSIONS: We developed a rapid, and quantitative method for identifying serum SM species using lipid hydrolase treatment and MALDI-TOF MS. This method will be suitable for clinical laboratory studies to examine the associations between SM species and disease states.

[Rapid and Easy Measurement of Serum Fatty Acid Composition of Neonates, Infants and Young People Using the Gas Chromatography Mass Spectrometry].

A variation of the fatty acid composition is closely associated with the clinical state of inflammatory disorder and metabolic syndrome. The analysis of serum fatty acid composition of neonates and infants has been measured hardly at the laboratory, because a large quantity of serum was required for an analysis and the measurement procedure was cumbersome. We examined the rapid and easy analysis in a small amount of serum using the combination methods of the gas chromatography mass spectrometry (GC MS) and the quick transmethylation. The serum fatty acid composition of neonates and infants were compared with the young people. The serum fatty acids with the internal standard material were performed transmethylation using the microwave, and then the lipids were extracted. The fatty acid esters were analyzed by GC MS with capillary column, and the statistical procedure used nonparametric method. The repeatability of each fatty acid concentration was CV = 5-11.3% (n = 5) with serum 50 µl. The lowest quantity of sample was possible to measure with 13 µl of serum. The total serum fatty acid, saturated fatty acid and monounsaturated fatty acid levels did not show a significant difference at all age, but the polyunsaturated fatty acid (PUFA) level of neonates and infants was significantly lower than young people, p = 0.007. The four main PUFA exclusive of α-linolenic acid showed a significant difference. The fatty acid composition with small quantities serum was measured by the rapid and accurate method using the GC MS and the microwave. The serum PUFA concentrations have fluctuated according to growth, therefore it was necessary to evaluate serum fatty acid composition in each age category.

A young patient with atypical type-B Wolff-Parkinson-White syndrome accompanied by left ventricular dysfunction.

A 15-year-old asymptomatic male patient presented with an electrocardiographic abnormality and left ventricular (LV) dysfunction (left ventricle ejection fraction of 40%) in a physical examination performed 2 years previously. LV dysfunction did not improve despite optimal medical therapy for dilated cardiomyopathy. Twelve-lead electrocardiography revealed a normal PR interval (138 ms) with a small delta-like wave in V2, but not a typical diagnostic wave that could be diagnosed as Wolff-Parkinson-White (WPW) syndrome by an electrocardiogram auto-analysis. Transthoracic echocardiography showed a remarkable asynchronous septal motion. An electrophysiological study was performed to exclude WPW syndrome. An accessory pathway (AP) was revealed on the lateral wall of the right ventricle, and radiofrequency catheter ablation was successfully performed to disconnect the AP. Thereafter, the dyssynchrony disappeared, and LV function improved. The intrinsic atrioventricular nodal conduction was very slow (A-H, 237 ms). The results of electrocardiogram auto-analysis could not be used to confirm the diagnosis of WPW syndrome because of the atypical delta wave. Conduction via the right lateral AP caused electrical dyssynchrony in the LV. This case suggests that atypical delta waves should be evaluated without depending on electrocardiographic auto-analyses in patients with LV dysfunction accompanied by dyssynchrony.

ß(2)-Adrenergic and M(2)-muscarinic receptors decrease basal t-tubular L-type Ca2+ channel activity and suppress ventricular contractility in heart failure.

L-type Ca(2+) channels (LTCC) play a crucial role in cardiac excitation-contraction coupling. We previously found that in failing ventricular myocytes of mice chronically treated with isoproterenol, basal t-tubular (TT) LTCC activity was halved by activation of protein phosphatase (PP)2A whereas basal surface sarcolemmal (SS) LTCC activity was doubled by inhibition of PP1. Interestingly, chronic treatment of these mice with pertussis toxin almost completely normalized TT and SS LTCC densities and cardiac contractility. In the present study, we therefore sought to identify the Gi/o protein-coupled receptors in cardiac myocytes (i.e. ß2-adrenergic, M2-muscarinic and A1-adenosine receptors) that are responsible for these abnormalities in heart failure by chronically administrating mice a selective antagonist of each receptor (ICI118,551, atropine and 8-cyclopentyl-1,3-dipropilxanthine (DPCPX), respectively) with isoproterenol. Compared with mice treated with isoproterenol alone, mice treated with isoproterenol plus ICI118,551 or atropine, but not DPCPX showed significantly lower lung weight/tibial length, higher fractional shortening, lower left ventricular end-diastolic pressure and higher dP/dtmax and dP/dtmin. In addition, ventricular myocytes of mice treated with isoproterenol plus ICI118,551 or atropine, but not DPCPX exhibited significantly higher TT and lower SS LTCC current densities than those of mice treated with isoproterenol alone due to normalization of the PP activities. These results indicate that ß2-adrenergic, M2-muscarinic, but not A1-adenosine receptors contribute to reduced ventricular contractility at least partially by decreasing basal TT LTCC activity in heart failure. Therefore, antagonists of ß2-adrenergic and/or M2-muscarinic receptors can be good adjuncts to ß1-adrenergic receptor antagonists in the treatment of heart failure.

High concentrations of omega-3 fatty acids are associated with the development of atrial fibrillation in the Japanese population.

The favorable effect of fish oils rich in n-3 polyunsaturated fatty acids (PUFAs) on the development of atrial fibrillation (AF) is controversial. The relationship between the serum concentrations of n-3 PUFAs and the incidence of AF is unclear; therefore, in the present study, we aimed to elucidate this relationship. We evaluated the serum concentrations of n-3 PUFAs in 110 patients with AF, 46 patients with ischemic heart disease (IHD) and no AF, and 36 healthy volunteers. Thirty-six patients had a history of IHD (IHD-AF group) and 74 did not (L-AF group). The eicosapentaenoic acid (EPA) levels in the L-AF group were higher than those in the IHD-AF and control groups (117 ± 64, 76 ± 30, and 68 ± 23 µg/ml, respectively); the docosahexaenoic acid (DHA) levels showed the same pattern (170 ± 50, 127 ± 27, and 126 ± 35 µg/ml, respectively). In both the L-AF and IHD-AF groups, the EPA levels in patients with persistent and permanent AF were higher than those in patients with paroxysmal AF (L-AF 131 ± 74 vs. 105 ± 51 µg/ml; IHD-AF 82 ± 28 vs 70 ± 33 µg/ml). Multivariate analysis showed that cases of AF were associated with higher levels of EPA but not DHA. In this Japanese population study, the EPA and DHA levels in patients with L-AF were higher than those in normal subjects. In particular, the EPA level was associated with the incidence of AF. These findings suggest that an excess of EPA might be a precipitating factor of AF.

Chronic receptor-mediated activation of Gi/o proteins alters basal t-tubular and sarcolemmal L-type Ca²âº channel activity through phosphatases in heart failure.

L-type Ca(2+) channels (LTCCs) play an essential role in the excitation-contraction coupling of ventricular myocytes. We previously found that t-tubular (TT) LTCC current density was halved by the activation of protein phosphatase (PP)1 and/or PP2A, whereas surface sarcolemmal (SS) LTCC current density was increased by the inhibition of PP1 and/or PP2A activity in failing ventricular myocytes of mice chronically treated with isoproterenol (ISO mice). In the present study, we examined the possible involvement of inhibitory heterotrimeric G proteins (G(i/o)) in these abnormalities by chronically administrating pertussis toxin (PTX) to ISO mice (ISO + PTX mice). Compared with ISO mice, ISO + PTX mice exhibited significantly higher fractional shortening of the left ventricle. The expression level of Gα(i2) proteins was not altered by the treatment of mice with ISO and/or PTX. ISO + PTX myocytes had normal TT and SS LTCC current densities because they had higher and lower availability and/or open probability of TT and SS LTCCs than ISO myocytes, respectively. A selective PKA inhibitor, H-89, did not affect LTCC current densities in ISO + PTX myocytes. A selective PP2A inhibitor, fostriecin, did not affect SS or TT current density in control or ISO + PTX myocytes but significantly increased TT but not SS LTCC current density in ISO myocytes. These results indicate that chronic receptor-mediated activation of G(i/o) in vivo decreases basal TT LTCC activity by activating PP2A and increases basal SS LTCC activity by inhibiting PP1 without modulating PKA in heart failure.

Low-dose rosuvastatin improves arterial stiffness in high-risk Japanese patients with dyslipdemia in a primary prevention group.

BACKGROUND: The treatment effects of rosuvastatin on arterial stiffness were assessed and compared to those of fluvastatin in high-risk Japanese patients with dyslipidemia in a primary prevention group. METHODS AND RESULTS: Patients were randomly assigned to either 2.5-5 mg/day of rosuvastatin (Group A) or 20-40 mg/day of fluvastatin (Group B) and followed up for 12 months. In Group A (n=38), there was a progressive reduction in brachial-ankle pulse wave velocity (baPWV) along with a decrease in the low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (L/H) ratio and high-sensitivity C-reactive protein (hsCRP), and the change in baPWV correlated significantly with that of the L/H ratio and that of hsCRP after rosuvastatin treatment. In Group B (n=37), although fluvastatin achieved a significant improvement in baPWV, L/H ratio, and hsCRP, baPWV was significantly greater than that in Group A and showed a significant correlation with that of hsCRP alone after fluvastatin treatment. In a subgroup of patients (n=26), switching from fluvastatin to rosuvastatin further improved baPWV and the L/H ratio without altering hsCRP after 12 months. CONCLUSIONS: Low-dose rosuvastatin would be more effective than fluvastatin in improving arterial stiffness in high-risk Japanese patients with dyslipidemia. The results suggest that improvement in arterial stiffness by rosuvastatin mainly depends on its strong lipid-lowering effects, whereas that by fluvastatin is strongly dependent on the pleiotropic effects, especially an anti-inflammatory action.

Inflammasome activation of cardiac fibroblasts is essential for myocardial ischemia/reperfusion injury.

Background- Inflammation plays a key role in the pathophysiology of myocardial ischemia/reperfusion (I/R) injury; however, the mechanism by which myocardial I/R induces inflammation remains unclear. Recent evidence indicates that a sterile inflammatory response triggered by tissue damage is mediated through a multiple-protein complex called the inflammasome. Therefore, we hypothesized that the inflammasome is an initial sensor for danger signal(s) in myocardial I/R injury. Methods and Results- We demonstrate that inflammasome activation in cardiac fibroblasts, but not in cardiomyocytes, is crucially involved in the initial inflammatory response after myocardial I/R injury. We found that inflammasomes are formed by I/R and that its subsequent activation of inflammasomes leads to interleukin-1ß production, resulting in inflammatory responses such as inflammatory cell infiltration and cytokine expression in the heart. In mice deficient for apoptosis-associated speck-like adaptor protein and caspase-1, these inflammatory responses and subsequent injuries, including infarct development and myocardial fibrosis and dysfunction, were markedly diminished. Bone marrow transplantation experiments with apoptosis-associated speck-like adaptor protein-deficient mice revealed that inflammasome activation in bone marrow cells and myocardial resident cells such as cardiomyocytes or cardiac fibroblasts plays an important role in myocardial I/R injury. In vitro experiments revealed that hypoxia/reoxygenation stimulated inflammasome activation in cardiac fibroblasts, but not in cardiomyocytes, and that hypoxia/reoxygenation-induced activation was mediated through reactive oxygen species production and potassium efflux. Conclusions- Our results demonstrate the molecular basis for the initial inflammatory response after I/R and suggest that the inflammasome is a potential novel therapeutic target for preventing myocardial I/R injury.

Decrease in the density of t-tubular L-type Ca2+ channel currents in failing ventricular myocytes.

In some forms of cardiac hypertrophy and failure, the gain of Ca(2+)-induced Ca(2+) release [CICR; i.e., the amount of Ca(2+) released from the sarcoplasmic reticulum normalized to Ca(2+) influx through L-type Ca(2+) channels (LTCCs)] decreases despite the normal whole cell LTCC current density, ryanodine receptor number, and sarcoplasmic reticulum Ca(2+) content. This decrease in CICR gain has been proposed to arise from a change in dyad architecture or derangement of the t-tubular (TT) structure. However, the activity of surface sarcolemmal LTCCs has been reported to increase despite the unaltered whole cell LTCC current density in failing human ventricular myocytes, indicating that the "decreased CICR gain" may reflect a decrease in the TT LTCC current density in heart failure. Thus, we analyzed LTCC currents of failing ventricular myocytes of mice chronically treated with isoproterenol (Iso). Although Iso-treated mice exhibited intact t-tubules and normal LTCC subunit expression, acute occlusion of t-tubules of isolated ventricular myocytes with osmotic shock (detubulation) revealed that the TT LTCC current density was halved in Iso-treated versus control myocytes. Pharmacological analysis indicated that kinases other than PKA or Ca(2+)/calmodulin-dependent protein kinase II insufficiently activated, whereas protein phosphatase 1/2A excessively suppressed, TT LTCCs in Iso-treated versus control myocytes. These results indicate that excessive ß-adrenergic stimulation causes the decrease in TT LTCC current density by altering the regulation of TT LTCCs by protein kinases and phosphatases in heart failure. This phenomenon might underlie the decreased CICR gain in heart failure.

Association between serum uric acid levels and cardiometabolic risk factors among Japanese junior high school students.

BACKGROUND: The present study was designed to examine whether serum uric acid (SUA) levels were associated with cardiometabolic risk factors and to determine optimal cut-offs for SUA to identify multiple risk factors among Japanese junior high school students. METHODS AND RESULTS: A total of 958 students (518 boys and 440 girls, aged 12.1-15.0 years) who were enrolled between April 2005 and June 2008 were divided into 4 groups according to SUA quartiles. Compared with the lowest quartile of SUA, prevalence of abdominal obesity, hypertension, and dyslipidemia was significantly increased in the highest quartile in boys and that of abdominal obesity was increased in the highest quartile in girls. The adjusted odds ratios (95% confidence interval) of the highest quartile of SUA for 2 or more cardiometabolic risk factors were 2.59 (1.16-5.79) for boys and 1.54 (0.43-5.56) for girls. Receiver operating characteristic curve analysis demonstrated that the most appropriate cut-offs for SUA to identify multiple cardiometabolic risk factors were 6.4 mg/dl for boys and 4.9 mg/dl for girls. CONCLUSIONS: SUA was strongly associated with the prevalence of cardiometabolic risk factors among male Japanese junior high school students. The present study may provide insights into the role of SUA in the school screening system for the development of educational programs on prevention of lifestyle-related diseases among school children.

Nonalcoholic fatty liver disease in Japanese junior high school students: its prevalence and relationship to lifestyle habits.

BACKGROUND: Despite the increase in nonalcoholic fatty liver disease (NAFLD) in Japanese adults, its prevalence in adolescents remains unclear. This prompted us to evaluate the incidence and clinical characteristics of NAFLD among junior high school students. METHODS: A population-based cross-sectional study was conducted among students in a single junior high school in Nagano prefecture. Serum alanine aminotransferase (ALT) and gamma-glutamyltransferase (gammaGT) measurements and abdominal ultrasonography were performed in 249 and 288 students in 2004 and 2007, respectively. In the latter survey, student lifestyle habits were also assessed, using questionnaires. RESULTS: The prevalence of NAFLD was 4.4% and 4.5% in 2004 and 2007, respectively, which was lower than that of obesity (10.0% and 5.9%). Body mass index and ALT and gammaGT levels increased significantly with hepatic steatosis severity. Multivariate logistic regression analysis demonstrated that the presence of obesity and an ALT level of 30 U/L or more were independent predictors of NAFLD (odds ratio 16.9, P<0.001 and odds ratio 16.6, P=0.001, respectively). The ratios of students commuting to and from school by car and not doing sports outside of school were higher in NAFLD students compared with non-NAFLD ones. Such tendencies were observed independently of the presence of obesity. Additionally, one obese student with severe steatosis and liver dysfunction was diagnosed as having nonalcoholic steatohepatitis (NASH). CONCLUSIONS: Approximately 4% of junior high school students had NAFLD that was primarily associated with obesity and reduced daily physical activity. Serum ALT measurement during school check-ups is recommended for the early detection of young adolescent NAFLD/NASH.

A new method for electric impedance imaging using an eddy current with a tetrapolar circuit.

A new contactless technique for electrical impedance imaging, using an eddy current managed along with the tetrapolar circuit method, is proposed. The eddy current produced by a magnetic field is superimposed on a constant current that is normally used in the tetrapolar circuit method, and thus is used to control the current distribution in the body. By changing the current distribution, a set of voltage differences is measured with a pair of electrodes. This set of voltage differences is used in the image reconstruction of the resistivity distribution. The least square error minimization method is used in the reconstruction algorithm. The principle of this method is explained theoretically. A backprojection algorithm was used to get 2-D images. Based on this principle, a measurement system was developed and model experiments were conducted with a saline-filled phantom. The estimated shape of each model in the reconstructed image was similar to that of the corresponding model. From the results of these experiments, it is confirmed that the proposed method is applicable to the realization of electrical conductivity imaging.

Risk stratification assessed by combined lung and heart iodine-123 metaiodobenzylguanidine uptake in patients with idiopathic dilated cardiomyopathy.

Iodine-123 metaiodobenzylguanidine (123I-MIBG) has been used to assess myocardial sympathetic nervous activity and severity of heart failure. (123)I-MIBG is also used as a potential marker of pulmonary endothelial cell function and may be related to pulmonary hypertension. Thus, we hypothesized that combined assessment of lung and heart 123I-MIBG kinetics predicts future clinical outcome more accurately than myocardial evaluation alone in patients with chronic heart failure. To test this hypothesis, we examined 123I-MIBG scintigrams in 62 consecutive patients with idiopathic dilated cardiomyopathy. Anterior planar images were obtained 15 minutes and 3 hours after 123I-MIBG injection. Cardiac and pulmonary 123I-MIBG activities were quantified as heart-to-mediastinum activity ratio and lung-to-mediastinum activity ratio. We introduced lung-to-heart activity ratio as the new 123I-MIBG parameter including myocardial sympathetic nerve activity and pulmonary endothelial cell function. Delayed lung-to-heart ratio was correlated with pulmonary vascular resistance (r = 0.48, p <0.0001), disease duration (r = 0.49, p <0.0001), and number of heart failure episodes (r = 0.55, p <0.0001). During a mean follow-up of 25 months, 15 patients had a cardiac event. Area under receiver operating characteristic curves for prediction of the event was greatest in delayed lung-to-heart ratio (lung to heart 0.92, heart to mediastinum 0.83, lung to mediastinum 0.80). In multivariate analysis, the lung-to-heart ratio (hazard ratio 2.76/0.1 increase, p = 0.002) was selected as an independent predictor for a future cardiac event. In conclusion, the combined assessment of lung and heart 123I-MIBG uptake may help to predict future clinical outcome for patients with idiopathic dilated cardiomyopathy more accurately than myocardial evaluation alone.

Fluvastatin improves arterial stiffness in patients with coronary artery disease and hyperlipidemia: a 5-year follow-up study.

BACKGROUND: The present study was designed to test the hypothesis that fluvastatin might improve arterial stiffness, as assessed with pulse wave velocity (PWV), in patients with coronary artery disease (CAD) and hyperlipidemia over the long term. METHODS AND RESULTS: Ninety-three patients were randomly assigned to either fluvastatin (group A, n=50) or bezafibrate (group B, n=43) and followed for 5 years. There was no difference in the clinical findings between the 2 groups. In group A, there was a progressive reduction in the brachial-ankle PWV along with a decrease in serum low-density lipoprotein-cholesterol (LDL-C) and C-reactive protein (CRP) by 12 months after fluvastatin, and the improvement was maintained until 5 years after treatment. In group B, despite identical lowering of the serum lipid, PWV was progressively increased. In group A, the percentage change in PWV correlated significantly with that of the serum CRP (r=0.49, p<0.001), but not with that of the serum LDL-C after treatment. CONCLUSIONS: The beneficial vascular effects of fluvastatin persisted for a long period in patients with CAD and hyperlipidemia. Its anti-inflammatory action might contribute to the favorable effects on arterial stiffness.

Effects of low-intensity resistance exercise with vascular occlusion on physical function in healthy elderly people.

Some successful fall prevention programs include resistance or balance training, but less is known about the effects of low-intensity resistance exercise with moderate vascular occlusion (LIO) on physical function in healthy elderly people. In LIO, appropriate pressure is applied to the proximal parts of the upper and lower extremities with a specially designed belt. The reduction of muscle blood flow is considered likely to induce the secretion of growth hormone. The aim of this study was to compare the effects of two training programs, LIO versus dynamic balance exercise (DBE) in elderly people in a community. Fifty-one healthy subjects aged 65 and older were randomly assigned to the LIO program (n = 24) or the DBE program (n = 27). Performance, balance, muscle strength were measured in both groups before and after the 8-week programs. In addition, blood was sampled from LIO participants (n = 11) and analyzed for growth hormone and lactate. Overall improvements, but no group differences, were found in performance and balance after the programs. Muscle strength in the lower extremities was significantly increased in the LIO group, but not in the DBE group. Growth hormone was significantly increased immediately after LIO. The 8-week LIO program improved physical function, especially muscle strength, which may be associated with the exercise-induced secretion of growth hormone. Further studies are needed to determine the contents and duration of an LIO program for elderly people.

A novel sphingosine-1-phosphate receptor agonist KRP-203 attenuates rat autoimmune myocarditis.

Sphingosine-1-phosphate (S1P) is an active sphingolipid metabolite that exerts important biological effects. Recently, we demonstrated that KRP-203 is a novel S1P receptor agonist that can alter lymphocyte homing and act as an immunomodulating agent. We investigated the efficacy of KRP-203 in the treatment of rat experimental autoimmune myocarditis. KRP-203 significantly attenuated the inflammation area, heart weight/body weight ratio, and left ventricular function. Immunohistochemical analysis and RT-PCR revealed that KRP-203 significantly decreased the infiltration of macrophages and CD4 T cells in the myocardium and the expression of inflammatory cytokines. Flow cytometric analysis revealed that treatment with KRP-203 effectively reduced the number of peripheral CD4 and CD8 T cells but not that of B cells and granulocytes. Further, late KRP-203 treatment was effective even against established EAM. These results demonstrate the therapeutic potential of KRP-203 for the treatment of human myocarditis and provide new insights into the pathogenesis of this disease.

Effect of single and multi-joint lower extremity muscle strength on the functional capacity and ADL/IADL status in Japanese community-dwelling older adults.

Forty-seven community-dwelling older adults aged >70 years participated in this Japanese cross-sectional study to determine the relationship between the isometric lower extremity muscle strength measured during knee extension (KE) in single-joint and total leg extension (TLE) in multi-joint tasks, physical performance tests, and functional status. The physical performance was determined by KE and TLE muscle strength, walking capacity, and balance performance tests, while the functional status was evaluated by interview using basic activities of daily living (ADL) and instrumental activities of daily living (IADL) tools. The results indicated that the TLE muscle strength was significantly related to all the other performance tests, while the KE muscle strength was not correlated with the balance test. Also, the bilateral TLE muscle strength was significantly associated with IADL status compared with the KE muscle strength. In conclusion, multi-joint muscle strength testing might be superior to single-joint muscle strength testing for the screening of the functional impairments of older adults.

Bone marrow-derived CXCR4+ cells mobilized by macrophage colony-stimulating factor participate in the reduction of infarct area and improvement of cardiac remodeling after myocardial infarction in mice.

The monocyte/macrophage lineage might affect the healing process after myocardial infarction (MI). Because macrophage colony-stimulating factor (M-CSF) stimulates differentiation and proliferation of this lineage, we examined the effect of M-CSF treatment on infarct size and left ventricular (LV) remodeling after MI. MI was induced in C57BL/6J mice by ligation of the left coronary artery. Either recombinant human M-CSF or saline was administered for 5 consecutive days after MI induction. M-CSF treatment significantly reduced the infarct size (P < 0.05) and scar formation (P < 0.05) and improved the LV dysfunction (percent fractional shortening, P < 0.001) after the MI. Immunohistochemistry revealed that M-CSF increased macrophage infiltration (F4/80) and neovascularization (CD31) of the infarct myocardium but did not increase myofibroblast accumulation (alpha-smooth muscle actin). M-CSF mobilized CXCR4(+) cells into peripheral circulation, and the mobilized CXCR4(+) cells were then recruited into the infarct area in which SDF-1 showed marked expression. The CXCR4 antagonist AMD3100 deteriorated the infarction and LV function after the MI in the M-CSF-treated mice. In conclusion, M-CSF reduced infarct area and improved LV remodeling after MI through the recruitment of CXCR4(+) cells into the infarct myocardium by the SDF-1-CXCR4 axis activation; this suggests that the SDF-1-CXCR4 axis is as a potential target for the treatment of MI.