BACKGROUND: Salvianolate is a compound mainly composed of salvia magnesium acetate, which is extracted from the Chinese herb Salvia miltiorrhiza . In recent years, salvianolate injection has been widely used in the treatment of cardiovascular diseases, but the mechanism of how it can alleviate cardiotoxicity remains unclear. METHODS: The cardiac injury model was constructed by treatment with doxorubicin (Dox) or azithromycin (Azi) in zebrafish larvae. Heart phenotype, heart rate, and cardiomyocyte apoptosis were observed in the study. RNA-sequencing (RNA-seq) analysis was used to explore the underlying mechanism of salvianolate treatment. Moreover, cardiomyocyte autophagy was assessed by in situ imaging. In addition, the miR-30a/becn1 axis regulation by salvianolate was further investigated. RESULTS: Salvianolate treatment reduced the proportion of pericardial edema, recovered heart rate, and inhibited cardiomyocyte apoptosis in Dox/Azi-administered zebrafish larvae. Mechanistically, salvianolate regulated the lysosomal pathway and promoted autophagic flux in zebrafish cardiomyocytes. The expression level of becn1 was increased in Dox-induced myocardial tissue injury after salvianolate administration; overexpression of becn1 in cardiomyocytes alleviated the Dox/Azi-induced cardiac injury and promoted autophagic flux in cardiomyocytes, while becn1 knockdown blocked the effects of salvianolate. In addition, miR-30a, negatively regulated by salvianolate, partially inhibited the cardiac amelioration of salvianolate by targeting becn1  directly. CONCLUSION This study has proved that salvianolate reduces cardiomyopathy by regulating autophagic flux through the miR-30a/becn1 axis in zebrafish and is a potential drug for adjunctive Dox/Azi therapy.
Animals ; Zebrafish ; MicroRNAs/genetics* ; Autophagy/drug effects* ; Myocytes, Cardiac/metabolism* ; Cardiomyopathies/metabolism* ; Beclin-1/genetics* ; Apoptosis/drug effects* ; Plant Extracts/therapeutic use* ; Doxorubicin

The study aims to examine the effects and potential mechanisms of disulfiram (DSF) on cardiac hypertrophic injury, focusing on the role of transforming growth factor-β-activated kinase 1 (TAK1)-mediated pan-apoptosis (PANoptosis). H9C2 cardiomyocytes were treated with angiotensin II (Ang II, 1 µmol/L) to establish an in vitro model of myocardial hypertrophy. DSF (40 µmol/L) was used to treat cardiomyocyte hypertrophic injury models, either along or in combination with the TAK1 inhibitor, 5z-7-oxozeaenol (5z-7, 0.1 µmol/L). We assessed cell damage using propidium iodide (PI) staining, measured cell viability with CCK8 assay, quantified inflammatory factor levels in cell culture media via ELISA, detected TAK1 and RIPK1 binding rates using immunoprecipitation, and analyzed the protein expression levels of key proteins in the TAK1-mediated PANoptosis pathway using Western blot. In addition, the surface area of cardiomyocytes was measured with Phalloidin staining. The results showed that Ang II significantly reduced the cellular viability of H9C2 cardiomyocytes and the binding rate of TAK1 and RIPK1, significantly increased the surface area of H9C2 cardiomyocytes, PI staining positive rate, levels of inflammatory factors [interleukin-1β (IL-1β), IL-18, and tumor necrosis factor α (TNF-α)] in cell culture media and p-TAK1/TAK1 ratio, and significantly up-regulated key proteins in the PANoptosis pathway [pyroptosis-related proteins NLRP3, Caspase-1 (p20), and GSDMD-N (p30), apoptosis-related proteins Caspase-3 (p17), Caspase-7 (p20), and Caspase-8 (p18), as well as necroptosis-related proteins p-MLKL, RIPK1, and RIPK3]. DSF significantly reversed the above changes induced by Ang II. Both 5z-7 and exogenous IL-1β weakened these cardioprotective effects of DSF. These results suggest that DSF may alleviate cardiac hypertrophic injury by inhibiting TAK1-mediated PANoptosis.
Animals ; MAP Kinase Kinase Kinases/physiology* ; Rats ; Myocytes, Cardiac/pathology* ; Disulfiram/pharmacology* ; Cardiomegaly ; Apoptosis/drug effects* ; Cell Line ; Angiotensin II ; Necroptosis/drug effects* ; Interleukin-1beta/metabolism* ; Receptor-Interacting Protein Serine-Threonine Kinases/metabolism* ; Lactones ; Resorcinols ; Zearalenone/administration & dosage*

OBJECTIVES: To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells). METHODS: H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe²⁺ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting. RESULTS: Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC₅₀ of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe²⁺ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1. CONCLUSIONS Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.
Ferroptosis/drug effects* ; Myocytes, Cardiac/cytology* ; Animals ; NF-E2-Related Factor 2/metabolism* ; Rats ; N-Acetylneuraminic Acid/pharmacology* ; Cell Hypoxia ; Reactive Oxygen Species/metabolism* ; Cell Line ; Myocardial Reperfusion Injury/metabolism*

OBJECTIVES: To explore the mechanism that mediate the therapeutic effect of quercetin on heart failure. METHODS: We searched the TCMSP and Swiss ADME databases for the therapeutic targets of quercetin and retrieved heart failure targets from the Genecards and OMIM databases. The intersecting targets were analyzed with GO and KEGG pathway analysis using DAVID database, and the key genes were identified via PPI analysis. Molecular docking between the core targets and quercetin was performed using PyMOL and AutoDock Tools. In a heart failure model established in H9C2 cardiomyocytes by treatment with isoproterenol, the effect of quercetin on the expressions of the MAPK signaling pathway was tested. RESULTS: A total of 60 intersecting targets were identified. Enrichment analysis revealed that quercetin may inhibit heart failure through the MAPK signaling pathway. The core genes, including AMPK3 and BCL-2, were identified as potential key regulators in quercetin-mediated improvement of heart failure. Cellular experiments demonstrated that quercetin significantly reduced isoproterenol-induced apoptosis of cardiomyocytes in a dose-dependent manner and obviously decreased the Bax/Bcl-2 ratio and the expression levels of caspase-3, ERK and p38 in the cells. CONCLUSIONS Quercetin improves heart failure possibly by inhibiting cardiomyocyte apoptosis through the MAPK signaling pathway.
Quercetin/pharmacology* ; Myocytes, Cardiac/drug effects* ; Heart Failure/metabolism* ; Apoptosis/drug effects* ; MAP Kinase Signaling System/drug effects* ; Rats ; Animals ; Isoproterenol

OBJECTIVES: To investigate the effects of quercetin on cuproptosis and L-type calcium currents in the myocardium of diabetic rats. METHODS: Forty SD rats were randomized into control group and diabetic model groups. The rat models of diabetes mellitus (DM) induced by high-fat and high-sugar diet combined with streptozotocin (STZ) injection were further divided into DM model group, quercetin treatment group, and empagliflozin treatment group (n=10). Blood glucose and body weight were measured every other week, and cardiac function of the rats was evaluated using echocardiography. HE staining, Sirius red staining, and wheat germ agglutinin (WGA) analysis were used to observe the changes in myocardial histomorphology, and serum copper levels and myocardial FDX1 expression were detected. In cultured rat cardiomyocyte H9c2 cells with high-glucose exposure, the effects of quercetin and elesclomol, alone or in combination, on intracellular CK-MB and LDH levels and FDX1 expression were assessed, and the changes in L-type calcium currents were analyzed using patch-clamp technique. RESULTS: The diabetic rats exhibited elevated blood glucose, reduced body weight, impaired left ventricular function, increased serum copper levels and myocardial FDX1 expression, decreased L-type calcium currents, and prolonged action potential duration. Quercetin and empagliflozin treatment significantly lowered blood glucose, improved body weight, and restored cardiac function of the diabetic rats, and compared with empagliflozin, quercetin more effectively reduced serum copper levels, downregulated FDX1 expression, and enhanced myocardial L-type calcium currents in diabetic rats. In H9c2 cells, high glucose exposure significantly increased myocardial expressions of FDX1, CK-MB and LDH, which were effectively lowered by quercetin treatment; Elesclomol further elevated FDX1, CK-MB and LDH levels in the exposed cells, and these changes were not significantly affected by the application of quercetin. CONCLUSIONS Quercetin ameliorates myocardial injury in diabetic rats possibly by suppressing myocardial cuproptosis signaling and restoring L-type calcium channel activity.
Animals ; Quercetin/pharmacology* ; Calcium Channels, L-Type/metabolism* ; Diabetes Mellitus, Experimental/metabolism* ; Rats, Sprague-Dawley ; Rats ; Myocytes, Cardiac/drug effects* ; Myocardium/pathology* ; Male

OBJECTIVES: To investigate the effect of cardiomyocytes-derived exosomes on lipopolysaccharide (LPS)-induced cardiomyocyte injury and its mechanism. METHODS: Exosomes isolated from rat cardiomyocytes with or without LPS treatment were co-cultured with rat lymphocytes. The lymphocytes with or without exosome treatment were co-cultured with LPS-induced rat cardiomyocytes for 48 h. Cardiomyocyte apoptosis was detected using flow cytometry, and the expressions of apoptosis marker proteins and the PI3K/AKT pathway proteins were detected using Western blotting. The effects of human recombinant IL-38 protein on apoptosis and protein expressions in LPS-induced cardiomyocytes were examined. RESULTS: Compared with normal cardiomyocyte-derived exosomes, the exosomes from LPS-induced cardiomyocytes significantly enhanced proliferation and increased mRNA and protein expression levels of IL-38 in rat lymphocytes. Bioinformatics analysis suggested that miR-1275 in the exosome played a key role in LPS-induced cardiomyocyte injury, and in dual luciferase reporter gene assay, miR-1275 mimics significantly increased luciferase activity of WT-IL-38. Co-culture with lymphocytes treated with exosomes from LPS-induced cardiomyocytes significantly inhibited apoptosis of LPS-induced cardiomyocytes. Treatment with recombinant IL-38 also effectively lowered apoptosis rate of LPS-induced cardiomyocytes, reduced cellular expression of Bax protein, and increased the protein expression levels of Bcl-2, p-PI3K and p-AKT. CONCLUSIONS miR-1275 in exosomes derived from LPS-induced cardiomyocytes mediates IL-38 up-regulation expression in lymphocytes to activate the PI3K/AKT pathway and inhibit LPS-induced cardiomyocyte apoptosis.
Apoptosis/drug effects* ; MicroRNAs/metabolism* ; Myocytes, Cardiac/metabolism* ; Animals ; Lipopolysaccharides ; Rats ; Exosomes/metabolism* ; Up-Regulation ; Interleukins/metabolism* ; Lymphocytes/cytology* ; Cells, Cultured ; Signal Transduction ; Coculture Techniques ; Phosphatidylinositol 3-Kinases/metabolism* ; Rats, Sprague-Dawley ; Humans ; Proto-Oncogene Proteins c-akt/metabolism*

OBJECTIVES: To verify whether hesperetin (Hes) alleviates doxorubicin (DOX)-induced cardiotoxicity by reducing inflammation via regulating the AMPK/NLRP3 pathway. METHODS: C57/bl6 mice and H9c2 cells treated with DOX to mimic cardiotoxicity were randomly divided into Sham (or control) group, DOX group, DOX+Hes group, DOX+Hes+compound C (CC, an AMPK inhibitor) group. Cardiac function and myocardial pathologies of the mice were evaluated, and the changes in H9c2 cell morphology and viability were assessed. Lactate dehydrogenase (LDH) activity in mouse myocardial tissues and H9c2 cells was measured using ELISA, and H9c2 cell apoptosis was detected with TUNEL staining. In both H9c2 cells and the myocardial tissues of the mice, cellular expression levels of TNF-α, IL-6 and IL-1β mRNAs and cleaved caspase-3, Bcl2, Bax, IL-1β, IL-18, p-AMPK, AMPK, p-mTOR, mTOR, NLRP3, ASC and caspase-1 proteins were detected using RT-PCR and Western blotting. RESULTS: DOX treatment caused cell swelling, decreased cell viability and increased LDH activity in H9c2 cells, resulting also in significantly increased cell apoptosis and cleaved caspase-3 expression and decreased Bcl2/Bax ratio. The DOX-treated mice showed obvious myocardial fiber swelling and inflammatory infiltration, decreased cardiac function and significantly increased myocardial LDH activity. In H9c2 cells, DOX treatment significantly increased the mRNA expressions of TNF-α, IL-6 and IL-1β and protein expressions of IL-1β and IL-18, lowered the expressions of p-AMPK and p-mTOR, and increased the expressions of NLRP3, ASC and caspase-1. Hes treatment obviously reduced these toxic effects of DOX in H9c2 cells, but its protective effects were blocked by application of compound C. CONCLUSIONS Hes reduces DOX-induced cardiotoxicity by inhibiting inflammation via regulating the AMPK/NLRP3 pathway.
Animals ; Doxorubicin/toxicity* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Mice, Inbred C57BL ; Mice ; Signal Transduction/drug effects* ; Cardiotoxicity ; AMP-Activated Protein Kinases/metabolism* ; Apoptosis/drug effects* ; Cell Line ; Myocytes, Cardiac/drug effects* ; Rats

OBJECTIVES: To explore the mechanism of cinnamic acid (CA) for improving doxorubicin-induced myocardial injury (DIC) in mice. METHODS: Network pharmacology analysis was used to obtain the key targets of CA and DIC. Male C57BL/6J mice were randomized into Sham, DOX, CA (25, 50 and 100 mg/kg)+DOX, and CA+Ferrostatin-1+DOX groups, and their myocardial function and pathology were examined by echocardiography and HE staining. Serum levels of CK-MB, LDH, MDA, IL-6, TNF‑α and myocardial ROS level were detected, and the expression levels of TLR4 and ferroptosis pathway proteins in myocardial tissue were detected by Western blotting. Cultured murine cardiomyocytes (HL-1 cells) with or without transfection with a small interfering RNA targeting TLR4 (si-TLR4) were treated with DOX or Erastin, and the cellular ROS content was measured by DCFH-DA staining; the expression level of GPX4 was detected using immunofluorescence staining. RESULTS: Network pharmacology analysis suggested that CA may improve DIC through TLR4 signaling. DOX treatment caused obvious myocardial injury in mice, which showed significantly increased serum levels of CK-MB, LDH, MDA, IL-6, TNF-α and myocardial ROS level with decreased myocardial levels of SLC7A11 and GPX4 proteins and increased levels of TLR4 and PTGS2 proteins. All these changes in the mouse models were significantly alleviated by treatment with CA, and the mice receiving CA or ferrostatin-1 treatment exhibited increased myocardial expressions of SLC7A11 and GPX4 proteins and lowered expressions of TLR4 and PTGS2 proteins. In cultured HL-1 cells, treatment with DOX and Erastin both obviously increased intracellular ROS level and decreased cellular GPX4 expression level, and these changes were strongly attenuated by TLR4 interference. CONCLUSIONS CA, as a potent herbal monomer, can effectively alleviate DIC in mice by inhibiting TLR4-mediated ferroptosis.
Animals ; Ferroptosis/drug effects* ; Toll-Like Receptor 4/metabolism* ; Myocytes, Cardiac/metabolism* ; Mice, Inbred C57BL ; Mice ; Male ; Doxorubicin/adverse effects* ; Cinnamates/pharmacology* ; Signal Transduction ; Reactive Oxygen Species/metabolism*

OBJECTIVES: To investigate the molecular mechanism by which salvianolic acid B (Sal-B) modulates mitochondrial functional homeostasis and alleviates myocardial ischemia-reperfusion (I/R) injury in mice. METHODS: Mouse cardiomyocyte HL-1 cells were pretreated with 5 μmol/L Sal-B with or without sh-Sirt1 transfection before exposure to hypoxia-reoxygenation (HR), and the changes in ATP production, mitochondrial superoxide activity, substrate oxidation level were evaluated. In the animal experiment, 36 C57BL/6J mice were randomized into 3 groups (n=12) for sham operation or ligation of the left anterior coronary artery to induce myocardial I/R injury with or without intravenous injection of Sal-B+I/R (50 mg/kg). In the rescue experiment, 60 adult C57BL/6J mice were randomized into 5 groups (n=12): sham-operated group, myocardial I/R group, Sal-B+I/R group, I/R+Sal-B+Sirt1fl/fl group, and I/R+Sal-B+cKO-Sirt1 group. Myocardial injury was evaluated with HE staining, and cardiac function was assessed by measurement of the ejection fraction and fractional shortening using echocardiography. RESULTS: In HL-1 cells with HR injury, Sal-B pretreatment significantly increased cellular ATP production, reduced mitochondrial superoxide anion levels, and enhanced oxygen consumption level. In the mouse models of myocardial I/R injury, Sal-B pretreatment markedly ameliorated I/R-induced structural disarray of the cardiac myocytes and improved cardiac ejection. Cycloheximide chase with Western blotting and ubiquitination assays after Sirt1-IP showed that Sal-B significantly inhibited Sirt1 degradation in HL-1 cells. Sirt1 knock-down reversed Sal-B-induced increases in ATP production, reduction in superoxide, and elevation of OCR in HL-1 cells. Cardiomyocyte-specific Sirt1 knockout obviously reversed Sal-B-mediated improvement in cardiac ejection function and myocardial structure damage in mice with myocardial I/R injury. CONCLUSIONS Sal-B promotes mitochondrial functional homeostasis in cardiomyocytes with HR injury and improves cardiac function in mice after myocardial I/R by inhibiting Sirt1 protein degradation.
Animals ; Sirtuin 1/metabolism* ; Myocardial Reperfusion Injury/physiopathology* ; Mice, Inbred C57BL ; Mice ; Myocytes, Cardiac/drug effects* ; Benzofurans/pharmacology* ; Homeostasis/drug effects* ; Male ; Mitochondria/drug effects* ; Depsides

OBJECTIVE: To investigate the effects of calcitonin gene-related peptide (CGRP) on autophagy in hypoxic/reoxygenated (H/R) cardiomyocytes and its relationship with the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway. METHODS: The rat cardiomyocyte cell line H9c2 was routinely cultured in vitro and passaged for experiments when the cells grew to 80% fusion. (1) CGRP dosage screening experiment: the cells were divided into blank control group, H/R group and different dosages of CGRP pretreatment groups. H9c2 cells were placed in a closed hypoxia chamber for 2 hours and then reoxygenated in a conventional incubator for 12 hours to prepare the H/R model. The CGRP pretreatment groups were pretreated with 0.01, 0.1, 0.5, 1, 5, and 10 μmol/L CGRP before the modeling process. The blank control group was not given any treatment. Cell counting kit-8 (CCK-8) was used to detect the cell survival rate, and the most suitable drug dosage was screened out. (2) Intervention experiment: H9c2 cells were divided into blank control group, H/R group, CGRP+H/R group, and CGRP+PI3K target inhibitor ly294002 (LY)+H/R group. H/R group was prepared as cellular H/R model. CGRP (1 μmol/L) alone or in combination with LY (10 μmol/L) was administered to CGRP+H/R group and CGRP+LY+H/R group, respectively, prior to the preparation of cellular H/R model. The blank control group was cultured routinely without treatment. The cell survival rate was detected by CCK-8. The level of lactate dehydrogenase (LDH) release was detected by colorimetric assay. The expressions of autophagy-related proteins [autophagy effector protein Beclin-1, microtubule-associated protein 1 light chain 3-II (LC3-II), autophagy protein p62] and PI3K/Akt/mTOR signaling pathway proteins [phosphorylated Akt (p-Akt), phosphorylated mTOR (p-mTOR)] were detected by Western blotting. RESULTS: (1) Results of CGRP dosage screening experiment: compared with the blank control group, the cell survival rate of the H/R group decreased significantly; and after giving 0.1, 0.5, 1, 5 μmol/L CGRP for pretreatment, the cell survival rate increased significantly, and intervention effect of 1 μmol/L CGRP was the best, and the difference was statistically significant when compared with that of the H/R group [(74.23±6.18)% vs. (23.43±4.09)%, P < 0.01], so it was used as the intervention dosage for the subsequent experiment. (2) Intervention experiment results: compared with the blank control group, the cell survival rate in the H/R group was significantly reduced, the level of LDH release was significantly increased, the protein expressions of Beclin-1 and LC3-II were significantly increased, and the protein expressions of p62, p-Akt and p-mTOR were significantly reduced, indicating that the death of cardiomyocytes occurred after the treatment of H/R and was accompanied by the elevation of autophagy level, and this process was associated with the activation of PI3K/Akt/mTOR signaling pathway. Compared with the H/R group, CGRP pretreatment increased cell survival rate [(76.02±2.43)% vs. (46.15±3.29)%, P < 0.01], decreased the level of LDH release (U/L: 169.83±11.65 vs. 590.17±34.50, P < 0.01), and down-regulated the protein expressions of Beclin-1 and LC3-II [Beclin-1 protein (Beclin-1/β-actin): 1.27±0.15 vs. 1.93±0.19, LC3-II protein (LC3-II/LC3-I): 1.27±0.13 vs. 1.98±0.18, both P < 0.01], up-regulated the protein expressions of p62, p-Akt, p-mTOR [p62 protein (p62/β-actin): 0.96±0.02 vs. 0.63±0.05, p-Akt protein (p-Akt/Akt): 0.76±0.04 vs. 0.48±0.02, p-mTOR protein (p-mTOR/mTOR): 1.13±0.09 vs. 0.68±0.15, all P < 0.05], suggesting that CGRP was able to reduce the H/R-induced cardiomyocyte injury, and this process was accompanied by a decrease in the level of cellular autophagy and activation of the PI3K/Akt/mTOR signaling pathway. Compared with the CGRP+H/R group, the cell survival rate was significantly lower than that in the CGRP+LY+H/R group [(56.95±6.63)% vs. (76.02±2.43)%, P < 0.01], LDH release level was significantly higher (U/L: 436.00±27.44 vs. 169.83±11.65, P < 0.01), and the protein expressions of Beclin-1 and LC3-II were significantly up-regulated [Beclin-1 protein (Beclin-1/β-actin): 1.63±0.12 vs. 1.27±0.15, LC3-II protein (LC3-II/LC3-I): 1.61±0.13 vs. 1.27±0.13, both P < 0.01], and significantly down-regulated p62, p-Akt, and p-mTOR protein expressions [p62 protein (p62/β-actin): 0.57±0.09 vs. 0.96±0.02, p-Akt protein (p-Akt/Akt): 0.45±0.01 vs. 0.76±0.04, p-mTOR protein (p-mTOR/mTOR): 0.66±0.06 vs. 1.13±0.09, all P < 0.05], suggesting that PI3K-targeted inhibitor was able to reverse the protective effect of CGRP on H/R cells. CONCLUSIONS CGRP pretreatment attenuated H/R-induced cardiomyocyte injury, increased cell survival rate, and reduced cellular LDH release. This effect may be achieved through inhibiting the activation of PI3K/Akt/mTOR signaling pathway.
Animals ; Myocytes, Cardiac/drug effects* ; Signal Transduction/drug effects* ; Rats ; TOR Serine-Threonine Kinases/metabolism* ; Calcitonin Gene-Related Peptide/pharmacology* ; Proto-Oncogene Proteins c-akt/metabolism* ; Autophagy/drug effects* ; Cell Line ; Cell Hypoxia ; Phosphatidylinositol 3-Kinases/metabolism*