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1.
Hypertens Res ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802501

RESUMO

Mineralocorticoid receptor (MR) is involved in the mechanisms of blood pressure elevation, organ fibrosis, and inflammation. MR antagonists have been used in patients with hypertension, heart failure, or chronic kidney disease. Esaxerenone, a recently approved MR blocker with a nonsteroidal structure, has demonstrated a strong blood pressure-lowering effect. However, blood pressure reduction may lead to sympathetic activation through the baroreflex. The effect of esaxerenone on the sympathetic nervous system remains unclear. We investigated the effect of esaxerenone on organ damage and the sympathetic nervous system in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), a well-established model of essential hypertension with sympathoexcitation and organ damage. Three-week administration of esaxerenone or hydralazine successfully attenuated the blood pressure elevation. Both esaxerenone and hydralazine comparably suppressed left ventricular hypertrophy and urinary albumin excretion. However, renal fibrosis and glomerular sclerosis were suppressed by esaxerenone but not hydralazine. Furthermore, plasma norepinephrine level, a parameter of systemic sympathetic activity, was significantly increased by hydralazine but not by esaxerenone. Consistent with these findings, the activity of the control centers of sympathetic nervous system, the parvocellular region of the paraventricular nucleus in the hypothalamus and the rostral ventrolateral medulla, was enhanced by hydralazine but remained unaffected by esaxerenone. These results suggest that esaxerenone effectively lowers blood pressure without inducing reflex sympathetic nervous system activation. Moreover, the organ-protective effects of esaxerenone appear to be partially independent of its blood pressure-lowering effect. In conclusion, esaxerenone demonstrates a blood pressure-lowering effect without concurrent sympathetic activation and exerts organ-protective effects in salt-loaded SHRSP. Esaxerenone has antihypertensive and cardiorenal protective effects without reflex sympathetic activation in salt-loaded stroke-prone spontaneously hypertensive rats.

2.
J Gen Intern Med ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782808

RESUMO

BACKGROUND: The triglyceride-glucose index (TyG index), calculated as the logarithmic product of fasting triglyceride and glucose concentrations, is recognized as a simple marker of insulin resistance. However, the association between the TyG index and future decline of renal function remains unclear in the general population. OBJECTIVE: To investigate whether the TyG index was associated with future decline of renal function in the general population who had not progressed to chronic kidney disease stage G2. DESIGN: Retrospective longitudinal observational cohort study. PARTICIPANTS: Individuals who received a population-based health checkup at JA Ehime Kouseiren Checkup Center from 2010 to 2019 (n = 134,007). Individuals without data of baseline fasting triglyceride or glucose levels, or baseline and follow-up data of estimated glomerular filtration rate (eGFR), or those with baseline eGFR < 60 mL/min/1.73 m2 were excluded. MAIN MEASURES: Future renal function decline, defined as a ≥ 25% decrease in eGFR from baseline. KEY RESULTS: Of 10,758 participants, 8,076 were classified into the low TyG index group (TyG index < 8.76, 1st to 3rd quartiles) and 2,682 into the high TyG index group (TyG index ≥ 8.76, 4th quartile). The mean follow-up period was 37.8 ± 23.6 months. The incidence rates of renal function decline were 0.31 and 0.69 per 100 person-years in the low and high TyG index groups, respectively. In multivariate Cox proportional hazard models, high TyG index was significantly associated with future renal function decline (hazard ratio 2.25, 95% CI 1.40-3.60). This association was consistent across subgroups stratified by age, sex, body mass index, baseline eGFR, and diagnosed hypertension, diabetes, or dyslipidemia. CONCLUSION: In the general population, high TyG index was associated with future renal function decline. The TyG index may be useful in identifying individuals at high risk for future renal function decline in the setting of health checkups.

3.
Circ J ; 88(4): 615-619, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38448007

RESUMO

The 87thAnnual Meeting of the Japanese Circulation Society (JCS2023) was held in March 2023 in Fukuoka, Japan, marking the first in-person gathering after the COVID-19 pandemic. With the theme of "New Challenge With Next Generation" the conference emphasized the development of future cardiovascular leaders and technologies such as artificial intelligence (AI). Notable sessions included the Mikamo Lecture on heart failure and the Mashimo Lecture on AI in medicine. Various hands-on sessions and participatory events were well received, promoting learning and networking. Post-event surveys showed high satisfaction among participants, with positive feedback on face-to-face interactions and the overall experience. JCS2023, attended by 17,852 participants, concluded successfully, marking a significant milestone in post-pandemic meetings, and advancing cardiovascular medicine.


Assuntos
Cardiologia , Sistema Cardiovascular , Humanos , Japão , Inteligência Artificial , Pandemias
4.
J Cardiovasc Electrophysiol ; 35(5): 906-915, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38433355

RESUMO

INTRODUCTION: Right ventricular (RV) pacing sometimes causes left ventricular (LV) systolic dysfunction, also known as pacing-induced cardiomyopathy (PICM). However, the association between specifically paced QRS morphology and PICM development has not been elucidated. This study aimed to investigate the association between paced QRS mimicking a complete left bundle branch block (CLBBB) and PICM development. METHODS: We retrospectively screened 2009 patients who underwent pacemaker implantation from 2010 to 2020 in seven institutions. Patients who received pacemakers for an advanced atrioventricular block or bradycardia with atrial fibrillation, baseline LV ejection fraction (LVEF) ≥ 50%, and echocardiogram recorded at least 6 months postimplantation were included. The paced QRS recorded immediately after implantation was analyzed. A CLBBB-like paced QRS was defined as meeting the CLBBB criteria of the American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society in 2009. PICM was defined as a ≥10% LVEF decrease, resulting in an LVEF of <50%. RESULTS: Among the 270 patients analyzed, PICM was observed in 38. Baseline LVEF was lower in patients with PICM, and CLBBB-like paced QRS was frequently observed in PICM. Multivariate analysis revealed that low baseline LVEF (odds ratio [OR]: 0.93 per 1% increase, 95% confidence interval [CI]: 0.89-0.98, p = 0.006) and CLBBB-like paced QRS (OR: 2.69, 95% CI: 1.25-5.76, p = 0.011) were significantly associated with PICM development. CONCLUSION: CLBBB-like paced QRS may be a novel risk factor for PICM. RV pacing, which causes CLBBB-like QRS morphology, may need to be avoided, and patients with CLBBB-like paced QRS should be followed-up carefully.


Assuntos
Potenciais de Ação , Bloqueio de Ramo , Estimulação Cardíaca Artificial , Cardiomiopatias , Eletrocardiografia , Frequência Cardíaca , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/terapia , Bloqueio Atrioventricular/etiologia , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/terapia , Bloqueio de Ramo/etiologia , Estimulação Cardíaca Artificial/efeitos adversos , Cardiomiopatias/fisiopatologia , Cardiomiopatias/etiologia , Cardiomiopatias/terapia , Cardiomiopatias/diagnóstico , Diagnóstico Diferencial , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Direita
7.
Hypertens Res ; 47(4): 1073-1077, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38337003

RESUMO

This study aimed to investigate whether renal denervation (RDN) reduces blood pressure and attenuates cardiac hypertrophy with decreasing sympathetic activity in spontaneously hypertensive rats (SHRs), a model of essential hypertension, during the established phase of hypertension. We performed RDN or sham operation in 15-weeks-old SHRs. Thirty days after RDN, mean blood pressure measured by telemetry, heart weight, left ventricular wall thickness assessed by echocardiography, and urinary norepinephrine levels were significantly decreased in the RDN group compared to the Sham group. Furthermore, oxidative stress, as indicated by thiobarbituric acid reactive substances, in the rostral ventrolateral medulla, a pivotal region regulating basal sympathetic tone, was significantly decreased in the RDN group. In conclusion, RDN reduces blood pressure and attenuates cardiac hypertrophy with sympathoinhibition in the established phase of hypertension in SHRs. These findings highlight the sympathoinhibitory effect of RDN and suggest that RDN may be a potential therapy for hypertensive cardiac hypertrophy. Renal denervation reduces blood pressure and attenuates cardiac hypertrophy with sympathoinhibition in the established phase of hypertension in spontaneously hypertensive rats. This study highlights the sympathoinhibitory effect of renal denervation and suggests that renal denervation may be a potential therapy for hypertensive cardiac hypertrophy.


Assuntos
Hipertensão , Rim , Ratos , Animais , Pressão Sanguínea/fisiologia , Ratos Endogâmicos SHR , Cardiomegalia , Denervação , Simpatectomia
8.
Sci Rep ; 14(1): 301, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167863

RESUMO

Electrocardiographic left ventricular hypertrophy (LVH) could predict adverse renal outcomes in patients with hypertension. This study aimed to investigate the association between electrocardiographic LVH and future decline in renal function in the general population using a dataset of population-based health checkups from 2010 to 2019 including 19,825 participants. Electrocardiographic LVH was defined according to the Minnesota code. Renal function decline was defined as a decrease of ≥ 25% in the estimated glomerular filtration rate from baseline to < 60 mL/min/1.73 m2. Electrocardiographic LVH was found in 1263 participants at the baseline visit. The mean follow-up period was 3.4 ± 1.9 years. The incidence rates of renal function decline were 0.30 and 0.78 per 100 person-years in the non-LVH group and LVH groups, respectively. Electrocardiographic LVH was associated with the risk for renal function decline in the adjusted analysis (hazard ratio 1.69, 95% confidence interval 1.14-2.50, P = 0.009). This association was comparable across subgroups stratified by age, sex, body mass index, diagnosed hypertension, systolic blood pressure, hemoglobin A1c, and urinary protein. This study underscores the usefulness of electrocardiographic LVH to detect high-risk individuals for renal function decline in the setting of health checkups in the general population.


Assuntos
Hipertensão , Hipertrofia Ventricular Esquerda , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Rim , Pressão Sanguínea , Incidência , Eletrocardiografia , Fatores de Risco
9.
Eur J Prev Cardiol ; 31(4): 448-457, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38078901

RESUMO

AIMS: Exercise intolerance is a clinical feature of patients with heart failure (HF). Cardiopulmonary exercise testing (CPET) is the first-line examination for assessing exercise capacity in patients with HF. However, the need for extensive experience in assessing anaerobic threshold (AT) and the potential risk associated with the excessive exercise load when measuring peak oxygen uptake (peak VO2) limit the utility of CPET. This study aimed to use deep-learning approaches to identify AT in real time during testing (defined as real-time AT) and to predict peak VO2 at real-time AT. METHODS AND RESULTS: This study included the time-series data of CPET recorded at the Department of Cardiovascular Medicine, Kyushu University Hospital. Two deep neural network models were developed to: (i) estimate the AT probability using breath-by-breath data and (ii) predict peak VO2 using the data at the real-time AT. The eligible CPET contained 1472 records of 1053 participants aged 18-90 years and 20% were used for model evaluation. The developed model identified real-time AT with 0.82 for correlation coefficient (Corr) and 1.20 mL/kg/min for mean absolute error (MAE), and the corresponding AT time with 0.86 for Corr and 0.66 min for MAE. The peak VO2 prediction model achieved 0.87 for Corr and 2.25 mL/kg/min for MAE. CONCLUSION: Deep-learning models for real-time CPET analysis can accurately identify AT and predict peak VO2. The developed models can be a competent assistant system to assess a patient's condition in real time, expanding CPET utility.


Cardiopulmonary exercise testing can be used to evaluate the condition of patients with heart failure during exercise. Developed deep-learning models can accurately predict a patient's anaerobic threshold in real time and peak oxygen uptake. The models can be used by clinicians for more objective and accurate assessments in real time, expanding the utility of cardiopulmonary exercise testing.


Assuntos
Aprendizado Profundo , Insuficiência Cardíaca , Humanos , Teste de Esforço/métodos , Limiar Anaeróbio , Consumo de Oxigênio , Insuficiência Cardíaca/diagnóstico
10.
Pacing Clin Electrophysiol ; 47(1): 5-18, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38112039

RESUMO

BACKGROUND: Precise mapping of the Purkinje fiber network is essential in catheter ablation of Purkinje-related ventricular arrhythmias (PrVAs). We sought to evaluate the mapping ability of a multi-spline duodecapolar catheter (PentaRay) for PrVAs. METHODS: Mappings of Purkinje fibers by PentaRay catheters were compared with those by conventional mapping catheters in consecutive patients undergoing catheter ablation of PrVAs from 2015 to 2022. RESULTS: Sixteen PrVAs (7 premature ventricular contractions or non-reentrant fascicular tachycardias [PVCs/NRFTs] and 9 fascicular ventricular tachycardias [FVTs]) were retrospectively studied. In PVCs/NRFTs, earliest preceding Purkinje potentials (PPs) could be recorded by the PentaRay catheters but not by the mapping and ablation catheters in 5 cases. At the earliest PP sites, the precedence from the QRS onset was greater, and the amplitude of the preceding potentials was higher in the PentaRay catheter compared with those in the mapping and ablation catheter (-62.0 ± 42.8 vs. -29.4 ± 34.2 ms, P = 0.02; 0.45 ± 0.43 vs. 0.09 ± 0.08 mV, P = 0.02). In FVTs, late diastolic potentials (P1) were recorded by the PentaRay catheters but not by the mapping and ablation catheters or the linear duodecapolar catheter in 2 cases. The amplitude of P1 was higher in the PentaRay catheter compared with that in the linear duodecapolar catheter and the mapping and ablation catheters (0.72 ± 0.49 vs. 0.17 ± 0.18 vs. 0.27 ± 0.21 mV, P = 0.0006, P = 0.002). The localized critical PPs, defined as the earliest preceding potentials in PVCs/NRFTs and P1 in FVTs, could be recorded in all the patients by the PentaRay catheter. The mapping ability of critical PPs of PrVAs was better with the PentaRay catheter than with the conventional mapping catheters (16/16 vs. 9/16, P = 0.004 by McNemar exact test). CONCLUSIONS: The PentaRay catheter has clinical advantages in mapping of the Purkinje fiber network to reveal critical PPs as ablation targets of PrVAs.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Taquicardia Ventricular/cirurgia , Eletrodos , Complexos Ventriculares Prematuros/cirurgia , Catéteres
11.
Eur Heart J Digit Health ; 4(4): 325-336, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37538146

RESUMO

Aims: We evaluated a self-care intervention with a novel mobile application (app) in chronic heart failure (HF) patients. To facilitate patient-centred care in HF management, we developed a self-care support mobile app to boost HF patients' optimal self-care. Methods and results: We conducted a multicentre, randomized, controlled study evaluating the feasibility of the self-care support mobile app designed for use by HF patients. The app consists of a self-monitoring assistant, education, and automated alerts of possible worsening HF. The intervention group received a tablet personal computer (PC) with the self-care support app installed, and the control group received a HF diary. All patients performed self-monitoring at home for 2 months. Their self-care behaviours were evaluated by the European Heart Failure Self-Care Behaviour Scale. We enrolled 24 outpatients with chronic HF (ages 31-78 years; 6 women, 18 men) who had a history of HF hospitalization. During the 2 month study period, the intervention group (n = 13) showed excellent adherence to the self-monitoring of each vital sign, with a median [interquartile range (IQR)] ratio of self-monitoring adherence for blood pressure, body weight, and body temperature at 100% (92-100%) and for oxygen saturation at 100% (91-100%). At 2 months, the intervention group's self-care behaviour score was significantly improved compared with the control group (n = 11) [median (IQR): 16 (16-22) vs. 28 (20-36), P = 0.02], but the HF Knowledge Scale, the General Self-Efficacy Scale, and the Short Form-8 Health Survey scores did not differ between the groups. Conclusion: The novel mobile app for HF is feasible.

13.
Sci Rep ; 13(1): 5203, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997629

RESUMO

Systemic inflammation underlies the association between obesity and nonalcoholic fatty liver disease (NAFLD). Here, we investigated functional changes in leukocytes' mitochondria in obese individuals and their associations with NAFLD. We analyzed 14 obese male Japanese university students whose body mass index was > 30 kg/m2 and 15 healthy age- and sex-matched lean university students as controls. We observed that the mitochondrial oxidative phosphorylation (OXPHOS) capacity with complex I + II-linked substrates in peripheral blood mononuclear cells (PBMCs), which was measured using a high-resolution respirometry, was significantly higher in the obese group versus the controls. The PBMCs' mitochondrial complex IV capacity was also higher in the obese subjects. All of the obese subjects had hepatic steatosis defined by a fatty liver index (FLI) score ≥ 60, and there was a positive correlation between their FLI scores and their PBMCs' mitochondrial OXPHOS capacity. The increased PBMCs' mitochondrial OXPHOS capacity was associated with insulin resistance, systemic inflammation, and higher serum levels of interleukin-6 in the entire series of subjects. Our results suggest that the mitochondrial respiratory capacity is increased in the PBMCs at the early stage of obesity, and the enhanced PBMCs' mitochondrial oxidative metabolism is associated with hepatic steatosis in obese young adults.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Adulto Jovem , Hepatopatia Gordurosa não Alcoólica/metabolismo , Leucócitos Mononucleares/metabolismo , Obesidade/metabolismo , Mitocôndrias/metabolismo , Inflamação/metabolismo , Estresse Oxidativo , Fígado/metabolismo
14.
Circ Res ; 132(9): 1110-1126, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36974722

RESUMO

BACKGROUND: Mitochondrial DNA (mtDNA)-induced myocardial inflammation is intimately involved in cardiac remodeling. ZBP1 (Z-DNA binding protein 1) is a pattern recognition receptor positively regulating inflammation in response to mtDNA in inflammatory cells, fibroblasts, and endothelial cells. However, the role of ZBP1 in myocardial inflammation and cardiac remodeling remains unclear. The aim of this study was to elucidate the role of ZBP1 in mtDNA-induced inflammation in cardiomyocytes and failing hearts. METHODS: mtDNA was administrated into isolated cardiomyocytes. Myocardial infarctionwas conducted in wild type and ZBP1 knockout mice. RESULTS: We here found that, unlike in macrophages, ZBP1 knockdown unexpectedly exacerbated mtDNA-induced inflammation such as increases in IL (interleukin)-1ß and IL-6, accompanied by increases in RIPK3 (receptor interacting protein kinase 3), phosphorylated NF-κB (nuclear factor-κB), and NLRP3 (nucleotide-binding domain and leucine-rich-repeat family pyrin domain containing 3) in cardiomyocytes. RIPK3 knockdown canceled further increases in phosphorylated NF-κB, NLRP3, IL-1ß, and IL-6 by ZBP1 knockdown in cardiomyocytes in response to mtDNA. Furthermore, NF-κB knockdown suppressed such increases in NLRP3, IL-1ß, and IL-6 by ZBP1 knockdown in response to mtDNA. CpG-oligodeoxynucleotide, a Toll-like receptor 9 stimulator, increased RIPK3, IL-1ß, and IL-6 and ZBP1 knockdown exacerbated them. Dloop, a component of mtDNA, but not Tert and B2m, components of nuclear DNA, was increased in cytosolic fraction from noninfarcted region of mouse hearts after myocardial infarction compared with control hearts. Consistent with this change, ZBP1, RIPK3, phosphorylated NF-κB, NLRP3, IL-1ß, and IL-6 were increased in failing hearts. ZBP1 knockout mice exacerbated left ventricular dilatation and dysfunction after myocardial infarction, accompanied by further increases in RIPK3, phosphorylated NF-κB, NLRP3, IL-1ß, and IL-6. In histological analysis, ZBP1 knockout increased interstitial fibrosis and myocardial apoptosis in failing hearts. CONCLUSIONS: Our study reveals unexpected protective roles of ZBP1 against cardiac remodeling as an endogenous suppressor of mtDNA-induced myocardial inflammation.


Assuntos
Infarto do Miocárdio , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , DNA Mitocondrial/genética , Interleucina-6/metabolismo , Remodelação Ventricular , Células Endoteliais/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/patologia , Inflamação/metabolismo , Camundongos Knockout , Interleucina-1beta/metabolismo , Proteínas de Ligação a RNA
15.
Circ J ; 87(4): 500-507, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36792220

RESUMO

BACKGROUND: Little is known about nationwide temporal trends in the clinical characteristics and treatment of dilated cardiomyopathy (DCM) in Japan.Methods and Results: We collected data regarding demographics, echocardiography, and treatment of DCM between 2003 to 2013 from Clinical Personal Records, a national registry organized by the Japanese Ministry of Health, Labour, and Welfare. Among the 40,794 DCM patients screened, 27,702 with left ventricular ejection fraction (LVEF) <50% and age ≥18 years were enrolled in this study and divided into 3 groups according to registration year: Group 1, 2003-2005 (10,006 patients); Group 2, 2006-2010 (11,252 patients); and Group 3, 2011-2013 (6,444 patients). Over time, there were decreases in age at registration (mean [±SD] 58.6±13.0 vs. 56.8±13.8 vs. 56.2±13.8 years; P<0.001) and LVEF (33.5±10.0% vs. 31.1±9.9% vs. 29.2± 9.7%; P<0.001), and an increase in patients with New York Heart Association Class III-IV (28.2% vs. 35.2% vs. 41.0%; P<0.001). The use of ß-blockers (59.1% vs. 79.3% vs. 87.8%; P<0.001) and mineralocorticoid receptor antagonists (30.6% vs. 35.8% vs. 39.7%; P<0.001) increased over time. In multivariate analysis, male sex, systolic blood pressure, chronic kidney disease, hemoglobin, and registration year were positively associated, whereas age and LVEF were negatively associated, with ß-blocker prescription. CONCLUSIONS: Although the clinical characteristics of DCM changed, the implementation of optimal medical therapy for DCM increased from 2003 to 2013 in Japan.


Assuntos
Cardiomiopatia Dilatada , Humanos , Masculino , Adolescente , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/complicações , Volume Sistólico , Função Ventricular Esquerda , Japão/epidemiologia , Antagonistas Adrenérgicos beta/uso terapêutico
18.
Front Sports Act Living ; 4: 969623, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570495

RESUMO

Exercise has long been known to effectively improve and enhance skeletal muscle function and performance. The favorable effects of exercise on remote organs other than skeletal muscle are well known, but the underlying mechanism has remained elusive. Recent studies have indicated that skeletal muscle not only enables body movement, but also contributes to body homeostasis and the systemic stress response via the expression and/or secretion of cytokines (so-called myokines). Not only the induction of muscle contraction itself, but also changes in intracellular calcium concentration ([Ca2+]i) have been suggested to be involved in myokine production and secretion. Caffeine is widely known as a Ca2+ ionophore, which improves skeletal muscle function and exercise performance (i.e., an "ergogenic aid"). Interestingly, some studies reported that caffeine or an increase in [Ca2+]i enhances the expression and/or secretion of myokines. In this review, we discuss the association between caffeine as an ergogenic aid and myokine regulation.

19.
Front Oncol ; 12: 1006322, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387253

RESUMO

Accumulating clinical data have demonstrated a clear positive association between cancer and cardiac disorders, particularly chronic heart failure (CHF). These two diseases can be mutual drivers of each other, and hence frequently co-occur in patients. The immune system is the core mechanism that eliminates transformed cells from our bodies. However, immune cells often play distinct or even conflicting roles in cancer and CHF. Moreover, CHF alters the properties of immune cells, particularly those of regulatory T cells. Our previous study showed that the oxidative phosphorylation capacity of peripheral blood mononuclear cells is impaired in CHF, leading to the increased production of reactive oxygen species. Therefore, the co-occurrence of cancer and CHF becomes a serious problem, affecting the treatment of both diseases, and consequently negatively affecting patient survival rates. To date, few methods have been identified that effectively treat both diseases at the same time. Mitochondria activity may change in immune cells during their activation and exhaustion, and in CHF. Mitochondria activity is also largely affected in myocardia in CHF. We here focus on the mitochondrial abnormalities of immune cells in cancer and CHF, and discuss possible ways to treat cancer and CHF at the same time by targeting mitochondrial abnormalities. Many cancer cells are inevitably produced daily in our bodies, mostly owing to enzymatic nucleotide errors of DNA replication and repair. Therefore, the possibility of ways to prevent cancer by preventing the onset of heart failure will also be discussed.

20.
Proc Natl Acad Sci U S A ; 119(41): e2203628119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36201541

RESUMO

Heart failure (HF) is a leading cause of death and repeated hospitalizations and often involves cardiac mitochondrial dysfunction. However, the underlying mechanisms largely remain elusive. Here, using a mouse model in which myocardial infarction (MI) was induced by coronary artery ligation, we show the metabolic basis of mitochondrial dysfunction in chronic HF. Four weeks after ligation, MI mice showed a significant decrease in myocardial succinyl-CoA levels, and this decrease impaired the mitochondrial oxidative phosphorylation (OXPHOS) capacity. Heme synthesis and ketolysis, and protein levels of several enzymes consuming succinyl-CoA in these events, were increased in MI mice, while enzymes synthesizing succinyl-CoA from α-ketoglutarate and glutamate were also increased. Furthermore, the ADP-specific subunit of succinyl-CoA synthase was reduced, while its GDP-specific subunit was almost unchanged. Administration of 5-aminolevulinic acid, an intermediate in the pathway from succinyl-CoA to heme synthesis, appreciably restored succinyl-CoA levels and OXPHOS capacity and prevented HF progression in MI mice. Previous reports also suggested the presence of succinyl-CoA metabolism abnormalities in cardiac muscles of HF patients. Our results identified that changes in succinyl-CoA usage in different metabolisms of the mitochondrial energy production system is characteristic to chronic HF, and although similar alterations are known to occur in healthy conditions, such as during strenuous exercise, they may often occur irreversibly in chronic HF leading to a decrease in succinyl-CoA. Consequently, nutritional interventions compensating the succinyl-CoA consumption are expected to be promising strategies to treat HF.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Acil Coenzima A , Difosfato de Adenosina/metabolismo , Ácido Aminolevulínico , Metabolismo Energético , Glutamatos/metabolismo , Insuficiência Cardíaca/metabolismo , Heme/metabolismo , Humanos , Ácidos Cetoglutáricos , Fosforilação Oxidativa
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