Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

Humans ; Myocardial Reperfusion Injury/genetics* ; RNA, Long Noncoding/genetics* ; Myocytes, Cardiac ; Apoptosis ; Myocardial Ischemia

Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

Humans ; Myocardial Reperfusion Injury/genetics* ; RNA, Long Noncoding/genetics* ; Myocytes, Cardiac ; Apoptosis ; Myocardial Ischemia

OBJECTIVE: To observe the effects of electroacupuncture (EA) on cardiac function and local field potential (LFP) in sensory and motor cortices in mice with stress cardiomyopathy (SC), and to explore the possible mechanism of EA in improving SC. METHODS: Twenty-seven female C57BL/6 mice were randomized into a blank group, a model group and an EA group, 9 mice in each group. In the model group and the EA group, SC model was established by continuous intraperitoneal injection of isoproterenol (ISO) for 14 days. At the same time of modeling, EA was applied at "Neiguan" (PC 6) and "Shenmen" (HT 7) in the EA group, with disperse-dense wave, in frequency of 2 Hz/15 Hz, 15 min each time, once a day for 14 days. After intervention, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test within 5 minutes were observed; the left ventricular function indexes (left ventricular diameter of end-diastole [LVIDd], left ventricular diameter of end-systole [LVIDs], left ventricular volume of end-diastole [LVEDV], left ventricular volume of end-systole [LVESV], ejection fraction [EF] and fraction shortening [FS]) were detected by echocardiography; the changes in ST-segment amplitude and PR interval of electrocardiogram were observed; the morphology of myocardial tissue was observed by HE staining; the serum levels of cortisol (CORT), cardiac troponin T (cTnT) and brain natriuretic peptide (BNP) were detected by ELISA; the changes of LFP in sensory and motor cortices were recorded by Plexon multi-channel acquisition system. RESULTS: Compared with the blank group, in the model group, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test were decreased (P<0.05); LVIDd, LVIDs, LVEDV and LVESV were increased (P<0.05), EF and FS were decreased (P<0.05); ST-segment amplitude was increased (P<0.05) and PR interval was prolonged (P<0.05); irregular myocardial fiber arrangement, interstitial edema and inflammatory cell infiltration were observed; the serum levels of CORT, cTnT and BNP were increased (P<0.05); in the sensory cortex, the ratios of delta, theta, alpha and beta frequency bands were increased (P<0.05), the maximum energy spectrum of theta and beta frequency bands was increased (P<0.05), the power spectral density (PSD) of delta, theta, alpha, beta and gamma frequency bands was increased (P<0.05); in the motor cortex, the ratios of delta, theta, alpha and beta frequency bands were increased (P<0.05), the maximum energy spectrum as well as PSD of delta, theta, alpha, beta and gamma frequency bands were increased (P<0.05). Compared with model group, in the EA group, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test were increased (P<0.05); LVIDd, LVIDs, LVEDV and LVESV were decreased (P<0.05), EF and FS were increased (P<0.05); ST-segment amplitude was decreased (P<0.05), and the PR interval was shortened (P<0.05); myocardial fiber injury and inflammatory cell infiltration were reduced; the serum levels of CORT, cTnT and BNP were decreased (P<0.05); in the sensory cortex, the ratios of theta, alpha and beta frequency bands were decreased (P<0.05), the ratio of gamma frequency band was increased (P<0.05), the maximum energy spectrum of theta frequency band as well as the PSD of theta, alpha, beta and gamma frequency bands were decreased (P<0.05); in the motor cortex, the ratios of theta, alpha and beta frequency bands were decreased (P<0.05) and the ratio of gamma frequency band was increased (P<0.05), the maximum energy spectrum of delta frequency band was increased (P<0.05), the maximum energy spectrum of theta frequency band as well as the PSD of theta and gamma frequency bands were decreased (P<0.05). CONCLUSION EA can improve cardiac function in mice with stress cardiomyopathy, and its mechanism may be related to the regulation of local field potentials in sensory and motor cortices.
Female ; Mice ; Animals ; Electroacupuncture ; Takotsubo Cardiomyopathy ; Motor Cortex ; Mice, Inbred C57BL ; Myocardium

Humans ; Muscular Dystrophy, Duchenne/epidemiology* ; Prevalence ; Myocardium

The present study was aimed to investigate the role and mechanism of glutaminolysis of cardiac fibroblasts (CFs) in hypertension-induced myocardial fibrosis. C57BL/6J mice were administered with a chronic infusion of angiotensin II (Ang II, 1.6 mg/kg per d) with a micro-osmotic pump to induce myocardial fibrosis. Masson staining was used to evaluate myocardial fibrosis. The mice were intraperitoneally injected with BPTES (12.5 mg/kg), a glutaminase 1 (GLS1)-specific inhibitor, to inhibit glutaminolysis simultaneously. Immunohistochemistry and Western blot were used to detect protein expression levels of GLS1, Collagen I and Collagen III in cardiac tissue. Neonatal Sprague-Dawley (SD) rat CFs were treated with 4 mmol/L glutamine (Gln) or BPTES (5 μmol/L) with or without Ang II (0.4 μmol/L) stimulation. The CFs were also treated with 2 mmol/L α-ketoglutarate (α-KG) under the stimulation of Ang II and BPTES. Wound healing test and CCK-8 were used to detect CFs migration and proliferation respectively. RT-qPCR and Western blot were used to detect mRNA and protein expression levels of GLS1, Collagen I and Collagen III. The results showed that blood pressure, heart weight and myocardial fibrosis were increased in Ang II-treated mice, and GLS1 expression in cardiac tissue was also significantly up-regulated. Gln significantly promoted the proliferation, migration, mRNA and protein expression of GLS1, Collagen I and Collagen III in the CFs with or without Ang II stimulation, whereas BPTES significantly decreased the above indices in the CFs. α-KG supplementation reversed the inhibitory effect of BPTES on the CFs under Ang II stimulation. Furthermore, in vivo intraperitoneal injection of BPTES alleviated cardiac fibrosis of Ang II-treated mice. In conclusion, glutaminolysis plays an important role in the process of cardiac fibrosis induced by Ang II. Targeted inhibition of glutaminolysis may be a new strategy for the treatment of myocardial fibrosis.
Rats ; Mice ; Animals ; Rats, Sprague-Dawley ; Angiotensin II/pharmacology* ; Fibroblasts ; Mice, Inbred C57BL ; Fibrosis ; Collagen/pharmacology* ; Collagen Type I/metabolism* ; RNA, Messenger/metabolism* ; Myocardium/pathology*

This study aimed to investigate the underlying mechanism of Zhenwu Decoction in the treatment of heart failure by regulating electrical remodeling through the transient outward potassium current(I_(to))/voltage-gated potassium(Kv) channels. Five normal SD rats were intragastrically administered with Zhenwu Decoction granules to prepare drug-containing serum, and another seven normal SD rats received an equal amount of distilled water to prepare blank serum. H9c2 cardiomyocytes underwent conventional passage and were treated with angiotensin Ⅱ(AngⅡ) for 24 h. Subsequently, 2%, 4%, and 8% drug-containing serum, simvastatin(SIM), and BaCl_2 were used to interfere in H9c2 cardiomyocytes for 24 h. The cells were divided into a control group [N, 10% blank serum + 90% high-glucose DMEM(DMEM-H)], a model group(M, AngⅡ + 10% blank serum + 90% DMEM-H), a low-dose Zhenwu Decoction-containing serum group(Z1, AngⅡ + 2% drug-containing serum of Zhenwu Decoction + 8% blank serum + 90% DMEM-H), a medium-dose Zhenwu Decoction-containing serum group(Z2, AngⅡ + 4% drug-containing serum of Zhenwu Decoc-tion + 6% blank serum + 90% DMEM-H), a high-dose Zhenwu Decoction-containing serum group(Z3, AngⅡ + 8% drug-containing serum of Zhenwu Decoction + 2% blank serum + 90% DMEM-H), an inducer group(YD, AngⅡ + SIM + 10% blank serum + 90% DMEM-H), and an inhibitor group(YZ, AngⅡ + BaCl_2 + 10% blank serum + 90% DMEM-H). The content of ANP in cell extracts of each group was detected by ELISA. The relative mRNA expression levels of ANP, Kv1.4, Kv4.2, Kv4.3, DPP6, and KChIP2 were detected by real-time quantitative PCR. The protein expression of Kv1.4, Kv4.2, Kv4.3, DPP6, and KChIP2 was detected by Western blot. I_(to) was detected by the whole cell patch-clamp technique. The results showed that Zhenwu Decoction at low, medium, and high doses could effectively reduce the surface area of cardiomyocytes. Compared with the M group, the Z1, Z2, Z3, and YD groups showed decreased ANP content and mRNA level, increased protein and mRNA expression of Kv4.2, Kv4.3, DPP6, and KChIP2, and decreased protein and mRNA expression of Kv1.4, and the aforementioned changes were the most notable in the Z3 group. Compared with the N group, the Z1, Z2, and Z3 groups showed significantly increased peak current and current density of I_(to). The results indicate that Zhenwu Decoction can regulate myocardial remodeling and electrical remodeling by improving the expression trend of Kv1.4, Kv4.2, Kv4.3, KChIP2, and DPP6 proteins and inducing I_(to) to regulate Kv channels, which may be one of the mechanisms of Zhenwu Decoction in treating heart failure and related arrhythmias.
Rats ; Animals ; Myocytes, Cardiac ; Atrial Remodeling ; Rats, Sprague-Dawley ; Heart Failure/metabolism* ; RNA, Messenger/metabolism* ; Potassium

Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.
Mice ; Animals ; Myocytes, Cardiac ; Phosphatidylinositol 3-Kinase/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Myocarditis/pathology* ; Exosomes/metabolism* ; bcl-2-Associated X Protein/metabolism* ; MicroRNAs/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis/genetics*

OBJECTIVE: To investigate the protective mechanisms of Chinese medicine Shexiang Tongxin Dropping Pills (STDP) on heart failure (HF). METHODS: Isoproterenol (ISO)-induced HF rat model and angiotensin II (Ang II)-induced neonatal rat cardiac fibroblast (CFs) model were used in the present study. HF rats were treated with and without STDP (3 g/kg). RNA-seq was performed to identify differentially expressed genes (DEGs). Cardiac function was evaluated by echocardiography. Hematoxylin and eosin and Masson's stainings were taken to assess cardiac fibrosis. The levels of collagen I (Col I) and collagen III (Col III) were detected by immunohistochemical staining. CCK8 kit and transwell assay were implemented to test the CFs' proliferative and migratory activity, respectively. The protein expressions of α-smooth muscle actin (α-SMA), matrix metalloproteinase-2 (MMP-2), MMP-9, Col I, and Col III were detected by Western blotting. RESULTS: The results of RNA-seq analysis showed that STDP exerted its pharmacological effects on HF via multiple signaling pathways, such as the extracellular matrix (ECM)-receptor interaction, cell cycle, and B cell receptor interaction. Results from in vivo experiments demonstrated that STDP treatment reversed declines in cardiac function, inhibiting myocardial fibrosis, and reversing increases in Col I and Col III expression levels in the hearts of HF rats. Moreover, STDP (6, 9 mg/mL) inhibited the proliferation and migration of CFs exposed to Ang II in vitro (P<0.05). The activation of collagen synthesis and myofibroblast generation were markedly suppressed by STDP, also the synthesis of MMP-2 and MMP-9, as well as ECM components Col I, Col III, and α-SMA were decreased in Ang II-induced neonatal rats' CFs. CONCLUSIONS STDP had anti-fibrotic effects in HF, which might be caused by the modulation of ECM-receptor interaction pathways. Through the management of cardiac fibrosis, STDP may be a compelling candidate for improving prognosis of HF.
Rats ; Animals ; Matrix Metalloproteinase 2/metabolism* ; Matrix Metalloproteinase 9/metabolism* ; RNA-Seq ; Transcriptome/genetics* ; Heart Failure/drug therapy* ; Collagen ; Collagen Type I/metabolism* ; Fibrosis ; Myocardium/pathology*