Effects of early and late aerobic exercise on right heart failure induced by monocrotaline in rats with pulmonary hypertension / 中国组织工程研究

BACKGROUND:Clinical studies have shown that aerobic exercise is an important supplement to the clinical treatment of patients with pulmonary hypertension,which can alleviate the disease condition,increase exercise tolerance and improve the quality of life.However,it is not clear whether patients at different stages of pulmonary hypertension can benefit equally from exercise training. OBJECTIVE:To compare the intervention effects of early or late aerobic training on right heart failure in rats with pulmonary hypertension and explore its possible mechanism. METHODS:Sixty male Wistar rats were randomly divided into control group,model sedentary group,model early exercise group and model late exercise group,with 15 rats in each group.The model of pulmonary hypertension was established by intraperitoneal injection of monocrotaline(60 mg/kg)in the latter three groups.The model early exercise group was given 8 weeks of treadmill aerobic exercise(60%maximum running speed,60 minutes per day,5 days a week)after modeling,while the model late exercise group was trained for 6 weeks after 2 weeks of modeling.The control and model sedentary groups were fed quietly in the rat cage for 8 weeks.After training,the exercise performance,right ventricular hemodynamics,cardiopulmonary function,cardiopulmonary histopathology,reactive oxygen species level in mitochondria,activity of mitochondrial respiratory chain complex and expressions of myocardial tissue proteins were detected. RESULTS AND CONCLUSION:Compared with the model sedentary group,exercise performance and right ventricular function improved(P<0.05),myocardial collagen content,endothelin-1,tumor necrosis factor-α/interleukin-10 ratio and β-myosin heavy chain/α-myosin heavy chain ratio decreased(P<0.05),vascular endothelial growth factor and sarcoplasmic reticulum calcium-adenosine triphosphate enzyme expression increased(P<0.05),immunofluorescence intensity of mitochondrial reactive oxygen species and the protein expression of 3-nitrotyrosine decreased(P<0.05),the activities of complex I,II,IV and V increased in the model early exercise and model late exercise groups(P<0.05),but there were no significant changes in right ventricular maximum pressure,pulmonary acceleration time and pulmonary artery wall area/total vascular area ratio(P>0.05).Compared with the model late exercise group,the model early exercise group further improved exercise performance and right ventricular function,and downregulated collagen content,brain natriuretic peptide protein expression,tumor necrosis factor-α/interleukin-10 ratio and β-myosin heavy chain/α-myosin heavy chain ratio(P<0.05).To conclude,although pulmonary vascular remodeling and right ventricular overload persist in rats with pulmonary hypertension,exercise training at different stages of the disease has a cardioprotective effect.The mechanism is related to the improvement of cardiac remodeling,neurohormone system imbalance,inflammatory response and mitochondrial oxidative stress.Greater benefit is gained from initiating exercise in the early stage of the disease.

Aerobic exercise modulates mitochondrial quality control system to reverse cardiac pathological remodeling in aging rats / 中国组织工程研究

BACKGROUND:Aging is associated with increased susceptibility to cardiovascular disease,and mitochondrial dysfunction plays a key role in the pathogenesis of cardiovascular disease.Regular physical activity is beneficial to cardiovascular health and can prevent and treat chronic heart disease.However,the specific mechanism of mitochondria in the protective effect of exercise on the aging heart has not yet been clarified. OBJECTIVE:To explore the effect of aerobic exercise on cardiac pathological remodeling in aging rats and to investigate the possible mechanism of mitochondrial quality control system. METHODS:Sixty Wistar rats were randomly divided into young sedentary group(6 months old),old sedentary group(20 months old)and old exercise group(20 months old)with 20 rats in each group.Rats in the young sedentary and old sedentary groups were fed in cages for 12 weeks,while those in the old exercise group underwent moderate-intensity aerobic treadmill exercise(60%of the maximal running speed,slope 0°,60 minute per day,5 days per week)for 12 weeks.After the experiment,the heart was extracted for relevant indicator tests. RESULTS AND CONCLUSION:Cardiac morphology and myocardial histopathology:compared with the young sedentary group,the rats in the old sedentary group presented with concentric cardiac hypertrophy,myocardial fibrosis,myocardial cell apoptosis and loss,and cardiac diastolic dysfunction(P＜0.05);compared with the old sedentary group,animals in the old exercise group showed reduced myocardial fibrosis and apoptosis rates,increased cell numbers,improved cardiac function(P＜0.05),and a transition in cardiac phenotype from pathological to physiological hypertrophy.Mitochondrial function:compared with the young sedentary group,the generation rate of mitochondrial hydrogen peroxide increased(P＜0.05),respiration rate and respiratory control ratio of state 3 and state 4 decreased(P＜0.05),activities of respiratory chain complexes Ⅰ,Ⅱ and Ⅳ decreased(P＜0.05),mitochondrial calcium retention capacity decreased(P＜0.05),and mitochondrial permeability transition pore opening increased(P＜0.05)in the old sedentary group.Compared with the old sedentary group,all of the above indicators were significantly improved in the old exercise group(P＜0.05).Mitochondrial quality control:compared with the young sedentary group,mitochondrial biogenesis decreased(P＜0.05),mitophagy activity increased(P＜0.05),mitochondrial fusion reduced(P＜0.05),and fission raised(P＜0.05)in the old sedentary group;compared with the old sedentary group,mitochondrial biogenesis and mitophagy activity increased(P＜0.05),mitochondrial fusion raised(P＜0.05)and fission decreased(P＜0.05)in the old exercise group.To conclude,regular aerobic exercises exert cardioprotective effects in aging rats by regulating the mitochondrial quality control system,thus reversing pathological cardiac remodeling and improving cardiac function.

Regulation of N6-methyladenosine on non-coding RNAs in pathological cardiac remodeling / 中国组织工程研究

BACKGROUND:N6-methyladenosine(m6A)is a hot research topic in the mechanism of pathological cardiac remodeling and plays an important role in the development of cardiovascular diseases. OBJECTIVE:To summarize the possible mechanism by which m6A modification in non-coding RNAs regulates the main processes of pathological cardiac remodeling,such as pathological cardiac hypertrophy,cardiomyocyte death,myocardial fibrosis and vascular remodeling. METHODS:"m6A,non-coding RNA,pathological cardiac hypertrophy,cardiomyocyte apoptosis,cardiomyocyte pyroptosis,cardiomyocyte ferroptosis,myocardial fibrosis,vascular remodeling"were used as search terms in Chinese and English.Relevant literature from CNKI,PubMed and Web of Science databases published from January 1974 to April 2023 was retrieved,and finally 86 eligible articles were reviewed. RESULTS AND CONCLUSION:m6A modification is a highly dynamic and reversible modification.Pathological cardiac remodeling mainly involves pathological cardiac hypertrophy,cardiomyocyte apoptosis,cardiomyocyte pyroptosis,cardiomyocyte ferroptosis,myocardial fibrosis and vascular remodeling.m6A-related enzymes can regulate pathological cardiac remodeling processes through various non-coding RNAs and different signaling pathways,which can be used as a new potential intervention for cardiovascular diseases.In pathological cardiac remodeling,research on the regulatory relationship between m6A modification and non-coding RNAs is still in its infancy.With the development of epigenetics,m6A modification in non-coding RNAs is expected to have a new development in the regulation of pathological cardiac remodeling.

Aerobic exercise preconditioning improves therapeutic effect of bone marrow mesenchymal stem cells on acute myocardial infarction / 中国组织工程研究

BACKGROUND:Stem cell therapy is an alternative treatment strategy for restoring damaged myocardial tissue after acute myocardial infarction.Exercise preconditioning can induce endogenous cardioprotective effects in the body.However,the efficacy and mechanism of the combined application are still unclear. OBJECTIVE:To explore the effect and possible mechanism of exercise preconditioning combined with bone marrow mesenchymal stem cells on the therapeutic effect in rats with acute myocardial infarction. METHODS:Seventy male SD rats were randomly divided into sham operation group,model group,stem cell therapy group,exercise preconditioning group,and combined intervention group.Rats in the exercise preconditioning group and combined intervention group underwent 8-week aerobic exercise on the treadmill before modeling.The animal model of acute myocardial infarction was made by ligating the anterior descending coronary artery.The stem cell therapy group and the combined intervention group were injected with bone marrow mesenchymal stem cells(1×109 L-1,1 mL)through the tail vein the next day after modeling.After 4 weeks of treatment,the exercise performance was evaluated by a graded treadmill exercise test.The cardiac structure and function were detected by echocardiography.The left ventricle was isolated.2,3,5-Triphenyltetrazolium chloride staining was used to evaluate myocardial infarct size.Masson staining was used to obtain collagen volume fraction.CD31 immunohistochemical staining was used to detect myocardial capillary density.TUNEL staining was used to detect myocardial cell apoptosis.Immunoblotting was used to detect protein expression levels of stromal cell-derived factor 1,CXC chemokine receptor protein 4,tumor necrosis factor-α,interleukin-10,and vascular endothelial growth factor. RESULTS AND CONCLUSION:(1)Intervention efficacy:Compared with the sham operation group,exercise performance,left ventricular ejection fraction,left ventricular fractional shortening,and CD31 positive cell rate decreased(P<0.05);myocardial infarct size,collagen volume fraction,and myocardial apoptotic rate increased(P<0.05)in the model group.Compared with the model group,exercise performance was not statistically significant(P>0.05)in the stem cell therapy group,and the exercise performance improved(P<0.05)in the exercise preconditioning and combined intervention groups;left ventricular ejection fraction,left ventricular fractional shortening,and CD31 positive cell rate increased(P<0.05),and the myocardial infarct size,collagen volume fraction,and cardiomyocyte apoptosis rate decreased(P<0.05)in the stem cell therapy,exercise preconditioning,and combined intervention groups.Compared with the stem cell therapy group,exercise performance,left ventricular ejection fraction,left ventricular shortening fraction,and CD31 positive cell rate increased(P<0.05),myocardial infarct size,collagen volume fraction,and myocardial cell apoptosis rate decreased(P<0.05)in the combined intervention group.(2)Protein expression:Compared with the sham operation group,the expression of tumor necrosis factor-α increased(P<0.05),while interleukin-10 and vascular endothelial growth factor expression decreased(P<0.05)in the model group.Compared with the model group,the expression of CXC chemokine receptor protein 4 increased(P<0.05)in the stem cell therapy group and combined intervention group,and the expression of tumor necrosis factor-α decreased(P<0.05)while interleukin-10 and vascular endothelial growth factor increased(P<0.05)in the stem cell therapy group,exercise preconditioning group,and combined intervention group.Compared with the stem cell therapy group,the expression of tumor necrosis factor-α decreased(P<0.05),while CXC chemokine receptor protein 4,interleukin-10,and vascular endothelial growth factor increased(P<0.05)in the combined intervention group.To conclude,exercise preconditioning can enhance the therapeutic effect of bone marrow mesenchymal stem cells in rats with acute myocardial infarction,which can inhibit cardiac remodeling,improve cardiac function,and delay the progress of heart failure.Its mechanism is related to the promotion of stem cell homing,inhibition of inflammatory response,and promotion of angiogenesis.

Effect and mechanism of angiotensin(1-7)supplementation combined with exercise therapy on cardiac remodeling in rats with renal hypertension / 中国组织工程研究

BACKGROUND:The renin-angiotensin system plays a key role in the occurrence and development of hypertension,in which angiotensin(1-7)has antihypertensive effect and reversely regulates the adverse effects of angiotensin Ⅱ.Exercise rehabilitation therapy is an important non-pharmaceutical means to prevent and treat hypertension;however,whether angiotensin(1-7)and exercise have a synergistic effect is not yet clear. OBJECTIVE:To explore the effect of angiotensin(1-7)supplementation combined with exercise therapy on cardiac remodeling in rats with renal hypertension and to investigate the possible mechanism of angiotensin(1-7)and its receptor signal axis. METHODS:Sixty male Sprague-Dawley rats were selected,of which 12 rats were randomly selected as normotensive group and the remaining 48 rats were used to make animal models of renal hypertension using two-kidney one-clip method and were then randomly divided into hypertension control group,hypertension exercise group,angiotensin(1-7)group and combined treatment group.One week after successful modeling,different interventions were given(for a period of 6 weeks)as follows:the hypertension exercise group was subjected to a running training on an electric treadmill,the angiotensin(1-7)group was perfused with angiotensin(1-7)by implanting Alzet microosmotic pump subcutaneously on the back of the rats,and the combined treatment group was perfused with angiotensin(1-7)after running training,while the normotensive group and hypertension control group were caged quietly.At 48 hours after the last training session,the tail artery blood pressure was measured with a non-invasive sphygmomanometer;the heart structure and function were detected by echocardiography;the left ventricular myocardium was taken for histopathological observation by hematoxylin-eosin and Masson staining,and the cardiomyocyte cross-sectional area and collagen volume fraction were obtained by image analysis software as markers of myocardial hypertrophy and fibrosis,respectively;the content of angiotensin(1-7)in the heart was detected by high performance liquid chromatography;the mRNA expression of cardiac embryonic genes,atrial natriuretic peptide and β-myosin heavy chain,was detected by real-time fluorescence quantitative PCR;and the protein expression of cardiac Mas receptor,angiotensin Ⅱ type 2 receptor and endothelial nitric oxide synthase was measured by western blot assay. RESULTS AND CONCLUSION:Compared with the normotensive group,blood pressure increased(P<0.05),cardiac function had no significant changes(P>0.05),cardiomyocyte cross-sectional area and collagen volume fraction increased(P<0.05),mRNA expression of atrial natriuretic peptide and β-myosin heavy chain was upregulated(P<0.05),angiotensin(1-7)content and protein expression of Mas receptor,angiotensin Ⅱ type 2 receptor and endothelial nitric oxide synthase was downregulated(P<0.05)in the hypertension control group.Compared with the hypertension control group,blood pressure decreased(P<0.05),cardiac function improved(P<0.05),collagen volume fraction decreased(P<0.05),cardiomyocyte cross-sectional area and angiotensin(1-7)content showed no significant changes(P>0.05),mRNA expression of atrial natriuretic peptide and β-myosin heavy chain was downregulated(P<0.05),and the protein expression of Mas receptor,angiotensin Ⅱ type 2 receptor and endothelial nitric oxide synthase was upregulated(P<0.05)in the hypertension exercise group;except for an increase in myocardial angiotensin(1-7)content(P<0.05),other parameters had no statistical significance(P>0.05)in the hypertension angiotensin(1-7)group.Compared with the hypertension exercise group,blood pressure decreased(P<0.05),cardiomyocyte cross-sectional area and cardiac function had no significant changes(P>0.05),collagen volume fraction decreased(P<0.05),angiotensin(1-7)content increased(P<0.05),mRNA expression of atrial natriuretic peptide and β-myosin heavy chain was downregulated(P<0.05),and the protein expression of Mas receptor,angiotensin Ⅱ type 2 receptor and endothelial nitric oxide synthase was upregulated(P<0.05)in the combined treatment group.To conclude,supplementation of angiotensin(1-7)alone cannot improve cardiac remodeling in rats with renal hypertension,but it can enhance the efficacy of exercise.The mechanism is related to the improvement of angiotensin(1-7)receptor deficiency and restoration of its signaling pathway function.

Granulocyte colony-stimulating factor combined with high-intensity intermittent exercise preconditioning improved cardiac remodeling in rats with acute myocardial infarction / 中国组织工程研究

BACKGROUND:Exercise training is an important non-drug rehabilitation method for many heart diseases,and it can also enhance the heart's tolerance to adverse stressors(such as myocardial ischemia),that is,exercise preconditioning.Granulocyte colony-stimulating factor can effectively mobilize stem cell homing and differentiation and promote the repair of damaged myocardium.However,the effect of the combination of the two treatments is not yet clear. OBJECTIVE:To explore the effect of granulocyte colony-stimulating factor supplementation combined with high-intensity intermittent exercise preconditioning on cardiac remodeling in rats with acute myocardial infarction and investigate its possible mechanism. METHODS:Totally 58 male Wistar rats were divided into sham group(n=10),model group(n=12),model drug group(n=12),model exercise group(n=12)and model combined treatment group(n=12).The myocardial infarction rat model was made by coronary artery ligation.The model exercise group and the model combined treatment group were pretreated with 8 weeks of high-intensity intermittent exercise on an electric treadmill before modeling.The model drug group and the model combined treatment group were subcutaneously injected with human recombinant granulocyte colony-stimulating factor 3 hours after modeling for 5 days(10 μg/kg per day).At 8 weeks after administration,echocardiography was used to detect heart structure and function;heart was stained with 2,3,5-triphenyltetrazolium chloride and Masson staining to obtain myocardial infarct area and collagen volume fraction,respectively.Vessel density and cell apoptosis rate were detected by immunofluorescence.Real-time fluorescent quantitative PCR was utilized to detect the mRNA expression of embryonic genes(brain natriuretic peptide,β-myosin heavy chain)and myocardial contraction regulatory factors(α-myosin heavy chain,sarcoplasmic reticulum Ca2+-ATPase).Western blot assay was used to detect the protein expression of cardiac stromal cell-derived factor 1,CXC chemokine receptor protein 4,Janus kinase 2(JAK2),signal transducer and activator of transcription 3(STAT3),Bcl2,Bax,and cleaved caspase-3. RESULTS AND CONCLUSION:(1)Compared with sham group,myocardial infarct size,collagen volume fraction,and apoptosis rate increased(P<0.05);vessel density,left ventricular fractional shortening,and left ventricular ejection fraction decreased(P<0.05);brain natriuretic peptide and β-myosin heavy chain mRNA increased(P<0.05),α-myosin heavy chain and sarcoplasmic reticulum Ca2+-ATPase mRNA and α-myosin heavy chain/β-myosin heavy chain ratio decreased(P<0.05);stromal cell-derived factor 1,CXC chemokine receptor protein 4,Bax,cleaved caspase-3 protein expression increased(P<0.05);p-JAK2,p-STAT3,and Bcl-2 protein expression decreased(P<0.05)in the model group.(2)Compared with the model group,the above indexes in the model drug and model exercise groups were significantly improved(P<0.05).Compared with the model drug and model exercise groups,the above parameters were further ameliorated(P<0.05)in the model combined treatment group.(3)The results showed that supplementation of granulocyte colony-stimulating factor or high-intensity intermittent exercise preconditioning alone can improve cardiac remodeling in rats with acute myocardial infarction,and the combined therapy has a better effect,which may be related to the induction of stem cell homing and the activation of JAK2/STAT3 signaling pathway to inhibit cardiomyocyte apoptosis.

Borneol attenuates inflammation and inhibits cardiac remodeling after myocardial infarction in mice via TRPM8 / 中国病理生理杂志

AIM:To examine the effects of borneol on inflammation and myocardial remodeling after myocar-dial infarction(MI)in mice,and to investigate the underlying mechanisms.METHODS:Eight-week-old wild-type(WT)C57BL/6 mice and transient receptor potential cation channel subfamily M member 8(TRPM8)gene knockout(TRPM8-/-)mice were randomly divided into sham and MI groups,and were subsequently treated with normal saline(control group)or borneol(borneol group)via gavage.Survival curves were plotted for WT and TRPM8-/-mice with MI treated with or with-out borneol.After 28 d,cardiac function of the mice was assessed through echocardiography,and haemodynamic indexes were evaluated using a multi-channel physiological instrument.Infarct size,myocardial hypertrophy and interstitial fibro-sis were assessed via pathological staining.In addition,inflammatory response in the peri-infarct region was detected.RE-SULTS:The TRPM8 expression was up-regulated in the peri-infarct region of the mice with MI(P＜0.05),and borneol had no effect on TRPM8 expression(P＞0.05).Borneol increased the survival rate,reduced the infarct size,inhibited car-diac remodeling and improved cardiac function in WT mice with MI(P＜0.05 or P＜0.01).However,it did not affect the survival rate,infarct size,myocardial hypertrophy,myocardial fibrosis or cardiac function in TRPM8-/-mice(P＞0.05).Furthermore,borneol reduced inflammatory cell infiltration and the expression of inflammatory cytokines,tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6 and monocyte chemotactic protein-1(MCP-1),in WT mice(P＜0.05 or P＜0.01)but not in TRPM8-/-mice(P＞0.05).CONCLUSION:Borneol attenuates inflammation,inhibits cardiac re-modeling and improves cardiac function in mice with MI via TRPM8.

The effects of aerobic exercise on endothelial nitric oxide synthase uncoupling in the myocardium of spontaneously hypertensive rats / 中华物理医学与康复杂志

Objective:To observe any effect of regular aerobic exercise on cardiac remodeling in spontaneously hypertensive rats (SHR) and explore the mechanism of endothelial nitric oxide synthase (eNOS) uncoupling.Methods:Thirty 6-week-old healthy male SHR were divided into a sedentary group and an exercise group, each of 15. Another ten age- and sex-matched Wistar-Kyoto rats were set as a normal control group. The animals in the normal control and sedentary groups were fed quietly in their cages, and those in the exercise group performed moderate intensity treadmill exercise for 8 weeks (5 times per week). Forty-eight hours after the last training, echocardiography was applied to document cardiac structure and function in both groups. Wheat germ agglutinin staining and Picrosirius Red staining were used to obtain the cardiomyocyte cross sectional areas (CSAs) and interstitial collagen volume fractions (CVFs) of all of the mice. The rates of cardiomyocyte apoptosis were measured using TUNEL staining, and myocardial tetrahydrobiopterin (BH4) content was measured using high-performance liquid chromatography. Total eNOS, eNOS dimer and eNOS monomer protein expression in the myocardia were detected using western blotting.Results:Compared with the normal control group, the left ventricular wall thickness (LVWT), myocardial CSA, CVF, apoptosis of cardiomyocytes and eNOS monomer levels were significantly higher in the sedentary group, on average. But the end-diastolic diameter (LVEDD) and ejection fraction (LVEF) of the left ventricle and the levels of eNOS dimer and myocardial BH4 and the eNOS dimer/monomer ratio tended to be lower. Comparing the exercise group with the sedentary group, the average LVEDD, LVEF, eNOS dimer, eNOS dimer/monomer ratio and myocardial BH4 content were significantly higher in the exercise group, but the myocardial CVF, cardiomyocyte apoptosis and eNOS monomer levels were significantly lower. LVWT and CSA were not significantly different. There were no significant differences in the total eNOS protein levels among the three groups.Conclusion:Regular aerobic exercise might improve cardiac remodeling in cases of spontaneous hypertension regulating eNOS uncoupling, at least in rats.

Mechanism of Shengmaisan Regulating Cardiac Remodeling of Arrhythmias with Deficiency of Qi and Yin / 中国实验方剂学杂志

Arrhythmia is an important disease among cardiovascular diseases. Malignant arrhythmias often occur clinically and are induced by abnormal ion channels， electrical activity disorders， myocardial fibrosis， inflammation， dysfunctional mitochondrial biogenesis， mitochondrial calcium overload， out-of-balance energy metabolism， oxidative stress， sympathetic hyperactivity， and other pathological cardiac remodeling， and they are the main causes of sudden cardiac death. In traditional Chinese medicine， arrhythmias are considered to be palpitations， which are commonly caused by deficiency of Qi and Yin. It is often manifested as a deficiency of the spleen and stomach， resulting in malfunction of the Qi mechanism， followed by a particularly severe decline in cardiac function. Shengmaisan is a representative formula for nourishing Qi and Yin， consisting of Ginseng Radix et Rhizoma， Ophiopogonis Radix， and Schisandrae Chinensis Fructus. In recent years， clinical studies have shown that Shengmaisan and its additions and subtractions are commonly used in the treatment of arrhythmias. In this article， the mechanisms of the active ingredients of Shengmaisan in the electrophysiology， biochemistry， structure， autonomic nervous system， and subcellular fraction of the heart are reviewed， and the multi-target， multi-system， and integrality of Shengmaisan in the treatment of arrhythmias of Qi and Yin deficiency are described. In addition， energy metabolism disorder is tightly juxtaposed with Qi and Yin deficiency syndrome. Mitochondria， as the center of myocardial energy metabolism， play a paramount role in cardiac remodeling， indicating that Shengmaisan will be a salient part of future research to ameliorate cardiac pathologic remodeling through energy metabolism of mitochondria， so as to provide a theoretical basis for the clinical treatment of these arrhythmias.

Como eu faço no Coração de Atleta: avaliação dos diferentes tipos de adaptação ao exercício / My approach to "Athlete'S Heart": evaluation of the different types of adaptation to exercise

A prática regular de esportes pode induzir adaptações no coração, sendo essa condição comumente chamada de "coração de atleta". As alterações observadas incluem dilatação das câmaras cardíacas, aumento da espessura miocárdica, melhora do enchimento ventricular, aumento da trabeculação do ventrículo esquerdo (VE), dilatação da veia cava inferior, entre outras. Essas alterações também podem ser observadas em algumas doenças cardíacas, como cardiomiopatia (CMP) dilatada, hipertrófica e outras. Dessa forma, os exames de imagem cardíaca são fundamentais na identificação dessas alterações e na diferenciação entre o "coração de atleta" e uma possível cardiopatia.(AU)

Exercise-induced adaptation may occur in amateur and professional athletes. This condition is commonly named "athlete's heart". The alterations observed include dilation of the heart chambers, increased myocardial thickness, improved ventricular filling, increased left ventricular trabeculation, dilation of the inferior vena cava, among others. These changes can also be observed in some heart diseases, such as dilated, hypertrophic and other cardiomyopathies (CMP). Thus, cardiac imaging tests are fundamental in identifying these alterations and in differentiating between "athlete's heart" and possible heart disease. (AU)

Effect of candesartan treatment on echocardiographic indices of cardiac remodeling in post-myocardial infarction patients

SUMMARY Objective: Myocardial infarction has unfavorable effect on structural and functional properties of the myocardium, referred to as cardiac remodeling. Left ventricular mass, left ventricular mass index, and relative wall thickness are important predictors of cardiac remodeling. In this study, we investigated the effect of candesartan treatment in comparison with zofenopril treatment on echocardiographic indices of cardiac remodeling in post myocardial infarction patients. Material and Methods: In this prospective study, patients who underwent successful percutaneous coronary intervention were randomly assigned to a candesartan or zofenopril treatment. After randomization, echocardiographic indices of cardiac remodeling including left ventricular mass, left ventricular mass index, and relative wall thickness were evaluated before the start of treatment along with 1- and 6-month follow-ups. Results: According to our study, candesartan group showed significant reduction of estimated left ventricular mass and left ventricular mass index at 6-month follow-up visit compared to baseline values (199.53±38.51 g vs. 212.69±40.82 g; 99.05 g/m2 (90.00-116.5) vs. 106.0 g/m2 (96.0∼123.00), p<0.05, respectively). This trend was also observed in zofenopril group during the 6-month period (201.22±40.07 g vs. 207.52±41.61 g; 101.0 g/m2 (92.25-111.75.0) vs. 104.50 g/m2 (95.0∼116.75), p<0.05, respectively). Although both classes of drugs had favorable effects on post-myocardial infarction cardiac remodeling, the absolute benefit was more prominent in candesartan group as compared to zofenopril group (p<0.05). Conclusion: Our results suggest that candesartan treatment following myocardial infarction may potentially be useful in terms of improving post-myocardial infarction cardiac remodeling.

Inhibitor of growth protein-2 silencing alleviates angiotensin Ⅱ-induced cardiac remodeling in mice by reducing p53 acetylation / 南方医科大学学报

OBJECTIVE@#To investigate the effect of inhibitor of growth protein-2 (Ing2) silencing on angiotensin Ⅱ (AngⅡ)-induced cardiac remodeling in mice and explore the underlying mechanism.@*METHODS@#An adenoviral vector carrying Ing2 shRNA or empty adenoviral vector was injected into the tail vein of mice, followed 48 h later by infusion of 1000 ng · kg-1 · min-1 Ang Ⅱ or saline using a mini-osmotic pump for 42 consecutive days. Transthoracic echocardiography was used to assess cardiac geometry and function and the level of cardiac hypertrophy in the mice. Masson and WGA staining were used to detect myocardial fibrosis and cross-sectional area of cardiomyocytes, and myocardial cell apoptosis was detected with TUNEL assay. Western blotting was performed to detect myocardial expressions of cleaved caspase 3, ING2, collagen Ⅰ, Ac-p53(Lys382) and p-p53 (Ser15); Ing2 mRNA expression was detected using real-time PCR. Mitochondrial biogenesis, as measured by mitochondrial ROS content, ATP content, citrate synthase activity and calcium storage, was determined using commercial assay kits.@*RESULTS@#The expression levels of Ing2 mRNA and protein were significantly higher in the mice with chronic Ang Ⅱ infusion than in saline-infused mice. Chronic infusion of AngⅡ significantly increased the left ventricular end-systolic diameter (LVESD) and left ventricular end-diastolic diameter (LVEDD) and reduced left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) in the mice. Ing2 silencing obviously alleviated AngⅡ-induced cardiac function decline, as shown by decreased LVEDD and LVESD and increased LVEF and LVFS, improved myocardial mitochondrial damage and myocardial hypertrophy and fibrosis, and inhibited cardiomyocyte apoptosis. Chronic AngⅡ infusion significantly increased myocardial expression levels of Ac-p53(Lys382) and p-p53(Ser15) in the mice, and Ing2 silencing prior to AngⅡ infusion lessened AngⅡ- induced increase of Ac-p53(Lys382) without affecting p53 (ser15) expression.@*CONCLUSION@#Ing2 silencing can inhibit AngⅡ-induced cardiac remodeling and dysfunction in mice by reducing p53 acetylation.

Effects of stem cells therapy combined with aerobic exercise on ventricular remodeling in rats with acute myocardial infarction / 中华物理医学与康复杂志

Objective:To explore the effect of supplementing stem cell therapy with aerobic exercise in left ventricle remodeling after myocardial infarction.Methods:Sixty 6-week-old male Wistar rats had acute myocardial infarction induced by ligation of the anterior descending coronary artery. They were then randomly divided into a model group, a stem cell group, an exercise group and an observation group. Another ten healthy Wistar rats formed a sham operation group. The rats in the stem cell and observation groups were infused with a suspension of bone marrow mesenchymal stem cells through the tail vein. Beginning four weeks later, the exercise and observation groups underwent 60 minutes of aerobic treadmill exercise 5 days per week for 8 weeks. At the beginning and end of the eight weeks the rats′ exercise performance was evaluated using a graded treadmill exercise test. And after the last training session cardiac structure and function were detected using ultrasound imaging. Tissue was then collected from the left ventricles and the collagen volume fractions were calculated. The expression of myocardial brain natriuretic peptide (BNP), heavy chain β-myosin (β-MHC) and α-MHC mRNA was detected using real-time fluorescence quantitative PCRs.Results:Compared with the sham operation group, the time and distance to exhaustion shortened significantly in the model group, with a significant decrease in the average maximum running speed, left ventricle ejection fraction (LVEF), left ventricle shortening fraction (LVFS), expression of α-MHC and the α-MHC/β-MHC ratio. There was a significant increase in the average resting heart rate, collagen volume fraction, expression of BNP and β-MHC in the model group. Compared with the model group, there was a significant increase in the average LVEF and LVFS of the stem cell group as well as in the time and distance to exhaustion, maximum running speed, expression of α-MHC and in the α-MHC/β-MHC ratio of the observation group, but a significant decrease in the average collagen volume fraction of the stem cell group compared with the observation group, together with the resting heart rate, collagen volume fraction, the expression of BNP and of β-MHC. Compared with the stem cell group, the observation group showed a significant increase in the average time and distance to exhaustion, maximum running speed, expression of α-MHC and the α-MHC/β-MHC ratio, with a significant decrease in the average resting heart rate, collagen volume fraction, expression of BNP and β-MHC.Conclusion:Aerobic exercise or stem cell therapy alone can inhibit left ventricular remodeling and improve cardiac function after myocardial infarction, at least in rats. The combination of the two treatments has a synergistic effect and can further enhance the effect of stem cell therapy.

The traditional Chinese medicines treat chronic heart failure and their main bioactive constituents and mechanisms

Chronic heart failure (CHF) is a severe public health problem with increasing morbidity and mortality, any treatment targeting a single session is insufficient to tackle this. CHF is characterized by reduced cardiac output resulting from neurohumoral dysregulation and cardiac remodeling, which might be related to oxidative stress, inflammation, endoplasmic reticulum stress, apoptosis, autophagy, mitochondrial function, and angiogenesis. These molecular mechanisms interact with each other through crosstalk. Historically, Chinese medicinal herbs have been widely applied in the treatment of CHF, and therapeutic effects of Chinese medicinal herbs and their ingredients have been scientifically confirmed over the past decades. Traditional Chinese medicine (TCM) with multiple components can confront the different pathogenesis of CHF through multiple targets. This review analyzes commonly used TCM patent drugs and TCM decoctions that are applicable to different stages of CHF based on clinical trials. Diverse bioactive ingredients in Chinese medicinal herbs have been found to treat CHF via multiple molecular mechanisms. This review comprehensively covers the key works on the effects and underlying mechanisms of TCM, herbal ingredients and synergistic effects of constituent compatibility in treating CHF, providing additional ideas to address this threat.

Angiotensin receptor-neprilysin inhibitors and cardiac remodeling

The aim of this study was to determine how sacubitril/valsartan compared with valsartan in an outpatient setting affects left ventricular remodeling in heart failure with reduced ejection fraction and functional (or secondary) mitral regurgitation (SMR) due to the effect of dual inhibition of the renin-angiotensin system and neprilysin. The outpatient study included 90 patients with chronic SMR who were followed up for 12 months. They received sacubitril/valsartan or valsartan instead of the more commonly used angiotensin-converting enzyme inhibitor enalapril for heart failure, in addition to standard medical therapy for heart failure. The difference in NT-proBNP change between groups was the primary endpoint. Changes in effective regurgitation orifice area, left ventricular ejection fraction, left ventricular end-systolic and end-diastolic volume indices, left atrial volume index, E/e' index, and exercise tolerance on the 6-minute walk test were secondary endpoints. In the treatment efficacy analysis, NT-proBNP levels decreased significantly by 37% in the sacubitril/valsartan group and by 11% in the valsartan group (P<0.001). Ejection fraction and exercise tolerance (increase in walking distance in the 6-min test) increased in the sacubitril/valsartan group (P<0.05). Also, in this group, the effective area of the regurgitation orifice, the left atrial volume index, the E/e' index, and the indices of the end-systolic and end-diastolic volume of the left ventricle (P<0.05) decreased more pronouncedly. Compared with valsartan, treatment with sacubitril/valsartan led to a significant improvement in cardiac remodeling in patients with SMR and heart failure with reduced ejection fraction.

Progress of pharmacotherapy for myocardial hypertrophy and cardiac remodeling / 中国临床药理学与治疗学

Cardiomyopathy is a disease with abnormal myocardial structure and function. For a long time, due to the limited understanding of cardiomyopathies, cardiomyopathies are treated empirically based on symptoms (such as heart failure, arrhythmia, etc.). Over years, with the improvement of diagnosis technology and the discover of disease mechanism, a variety of drugs have been approved, such as tafamidis, patisiran and Inotersen. Many more drugs have completed preliminary safety and efficacy verification and entered Phase III trials. In addition, some cutting-edge technologies are also being developed, such as siRNA drug patisiran, CRISPR/Cas9 gene editing technology drug NTLA-2001, stem cell therapy, etc. This article discusses two cardiac problems that may be caused by cardiomyopathy: myocardial hypertrophy and cardiac remodeling, and introduces the pharmacology and related research of the latest drugs for these diseases.

Effects of activated CD4 + T cell-derived exosomes on cardiac remodeling after myocardial infarction / 中华危重病急救医学

Objective:To explore the role of activated CD4 + T cells in cardiac remodeling after myocardial infarction (MI). Methods:① Experiment in vitro: naive CD4 + T cells were isolated in mouse spleen, and then stimulated with plate-bound anti-CD3 and anti-CD28 for 48 hours. Exosomes isolated from the supernatant of activated CD4 + T cells were incubated with cardiac fibroblasts (CFs) for 48 hours, and then the ability of CFs proliferation, migration and differentiation were detected by cell counting kit-8 (CCK-8) assay, Transwell assay, and immunofluorescence assay. ② Experiment in vivo: 40 male C57 mice were divided into 4 groups according to random number table method, including control group (Ctrl group), sham operation group (Sham group), MI group, and exosome treatment group (MI+Exo group), with 10 in each group. The mice model of MI was established by ligating the left anterior descending coronary artery. In MI+Exo group, 40 μg/d exosomes were injected intravenously into the tail after modeling. Cardiac function and cardiac fibrosis post-MI were assessed by echocardiography and quantitative polymerase chain reaction (qPCR) at 4th week. Results:① In vitro: exosomes derived from activated CD4 + T cells significantly promote CFs proliferation, migration and differentiation [proliferation ability ( A value): 0.31±0.01 vs. 0.21±0.01, migration capability (cells/MP): 79.20±3.34 vs. 48.80±2.13, differentiation ability (α-smooth muscle actin, α-SMA; fluorescence intensity): 1.56±0.03 vs. 1.00±0.02, all P < 0.05]. ② In vivo: echocardiographic analysis showed that exosomes derived from activated CD4 + T cells aggravated the deterioration of cardiac dysfunction post-MI than MI group, as indicated by left ventricular ejection fraction (LVEF) and fractional shortening (FS) decreased significantly [LVEF: 0.185±0.008 vs. 0.257±0.022, FS: (9.72±1.72)% vs. (14.08±1.08)%, both P < 0.05], left ventricular end-diastolic diameter (LVEDD) and left ventricular end-systolic diameter (LVESD) increased significantly [LVEDD (mm): 5.43±0.29 vs. 4.62±0.35, LVESD (mm): 4.94±0.12 vs. 3.69±0.29, both P < 0.05]. Additionally, qPCR showed that exosomes derived from activated CD4 + T cells remarkably promoted myocardial fibrosis post-MI than MI group, as indicated by the mRNA expression of α-SMA, collagens (Col1a1, Col3a1) in MI+Exo group was significantly higher than that in MI group [α-SMA (2 -ΔΔCT): 4.72±0.89 vs. 3.58±0.78, Col1a1 (2 -ΔΔCT): 6.59±0.56 vs. 4.23±0.42, Col3a1 (2 -ΔΔCT): 13.40±1.03 vs.4.96±0.36, all P < 0.05]. Conclusion:Activated CD4 + T cells promote cardiac remodeling following MI through transferring exosomes to CFs.

Protective effects of rice bran hydrolysates on heart rate variability, cardiac oxidative stress, and cardiac remodeling in high fat and high fructose diet-fed rats

Objective: To examine the ameliorative effect of rice bran hydrolysates (RBH) on metabolic disorders, cardiac oxidative stress, heart rate variability (HRV), and cardiac structural changes in high fat and high fructose (HFHF)-fed rats.Methods: Male Sprague-Dawley rats were daily fed either standard chow diet with tap water or an HFHF diet with 10％ fructose in drinking water over 16 weeks. RBH (500 and 1000 mg/kg/day) was orally administered to the HFHF-diet-fed rats during the last 6 weeks of the study period. At the end of the treatment, metabolic parameters, oxidative stress, HRV, and cardiac structural changes were examined. Results: RBH administration significantly ameliorated metabolic disorders by improving lipid profiles, insulin sensitivity, and hemodynamic parameters. Moreover, RBH restored HRV, as evidenced by decreasing the ratio of low-frequency to high-frequency power of HRV, a marker of autonomic imbalance. Cardiac oxidative stress was also mitigated after RBH supplementation by decreasing cardiac malondialdehyde and protein carbonyl, upregulating eNOS expression, and increasing catalase activity in the heart. Furthermore, RBH mitigated cardiac structural changes by reducing cardiac hypertrophy and myocardial fibrosis in HFHF-diet-fed rats. Conclusions: The present findings suggest that consumption of RBH may exert cardioprotective effects against autonomic imbalances, cardiac oxidative stress, and structural changes in metabolic syndrome.

Effects of PNU 282987 on Improving Cardiac Remodeling and JAK 2/STAT3 Signaling Pathway / 中国药房

OBJECTIVE：To st udy the effects of α7 nicotinic acetylcholine receptor agonists （PNU282987）on improving cardiac remodeling of mice and Janus kinase 2/signal transducer and activator of transcription 3（JAK2/STAT3）signaling pathway. METHODS：Male Kunming mice were randomly divided into normal control group ，model group ，propranolol group （positive control，i.g. 40 mg/kg）and PNU 282987 low-dose，medium-close and high-dose groups （intraperitoneal injection of 0.5，1.0，3.0 mg/kg），with 10 mice in each group. Except for the normal control group ，mice in the other groups were given isoproterenol （ISO，30 mg/kg） subcutaneously for 7 days to induce the cardiac remodeling model. After 30 minutes of ISO injection ， administration groups were given relevant liquid ，once a day ，for 7 consecutive days. Twelve hours after last administration ，the left ventricular ejection fraction （EF）and left ventricular short axis shortening rate （FS）of mice in each group were measured ，and the whole heart mass index （HMI）was calculated ；the pathological changes of myocardium were observed. The serum contents of lactate dehydrogenase （LDH），creatine kinase （CK），tumor necrosis factor α（TNF-α），interleukin 6（IL-6），the protein expression of intercellular adhesion molecule 1（ICAM-1）and adhesion molecule 1（VCAM-1）were also determined. The ratios of p-JAK2/JAK2，p-STAT3/STAT3 in myocardial tissue were detected. RESULTS ：Compared with normal control group ，EF and FS of model group were significantly reduced ，HMI，the contents of LDH，CK，TNF-α and IL-6，the protein expression of ICAM- 1 and VCAM- 1，the ratio of p-JAK 2/JAK2 and p-STAT 3/STAT3 were increased significantly （P＜0.05 or P＜0.01）； blue collagen deposition in the interstitium of myocardium was obvious，and the degree of fibrosis was severe. Compared with model group ， the EF and FS of the mice in the medium-dose and high-dose groups were increased significantly ， HMI （except for PNU 282987 medium-dose group ），the contents of LDH （except for PNU 282987 medium-dose group ），CK，TNF-α and IL-6，the protein expression of ICAM- 1 and VCAM- 1，the ratio of p-JAK 2/JAK2 and p-STAT 3/STAT3 were decreased significantly （P＜0.05 or P＜ 0.01）；blue collagen deposition in the myocardial interstitium was significantly reduced ，and the degree of myocardial fibrosis was significantly reduced. There was no significant difference in the comparison of the above indicators in PNU 282987 low-dose group （P＞0.05）. CONCLUSIONS ：PNU282987 can improve cardiac remodeling of mice ，the mechanism of which may be associated with inhibiting JAK 2/STAT3 signaling pathway.