Pathological cardiac hypertrophy induced by angiotensin II (AngII) can subsequently give rise to heart failure, a leading cause of mortality. Nardosinone is a pharmacologically active compound extracted from the roots of Nardostachys chinensis, a well-known traditional Chinese medicine. In order to investigate the effects of nardosinone on AngII-induced cardiac cell hypertrophy and the related mechanisms, the myoblast cell line H9c2, derived from embryonic rat heart, was treated with nardosinone (25, 50, 100, and 200 μmol/L) or AngII (1 μmol/L). Then cell surface area and mRNA expression of classical markers of hypertrophy were detected. The related protein levels in PI3K/Akt/mTOR and MEK/ERK signaling pathways were examined by Western blotting. It was found that pretreatment with nardosinone could significantly inhibit the enlargement of cell surface area induced by AngII. The mRNA expression of ANP, BNP and β-MHC was obviously elevated in AngII-treated H9c2 cells, which could be effectively blocked by nardosinone at the concentration of 100 μmol/L. Further study revealed that the protective effects of nardosinone might be mediated by repressing the phosphorylation of related proteins in PI3K/Akt and MEK/ERK signaling pathways. It was suggested that the inhibitory effect of nardosinone on Ang II-induced hypertrophy in H9c2 cells might be mediated by targeting PI3K/Akt and MEK/ERK signaling pathways.
Angiotensin II ; physiology ; Animals ; Cardiotonic Agents ; pharmacology ; Cell Line ; Cell Size ; drug effects ; Hypertrophy ; metabolism ; pathology ; MAP Kinase Signaling System ; Myoblasts, Cardiac ; cytology ; drug effects ; metabolism ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Sesquiterpenes ; pharmacology ; TOR Serine-Threonine Kinases ; genetics ; metabolism

OBJECTIVETo investigate whether Astragaloside IV(AST) protects H9c2 cells against H2O2-induced oxidative injury partly through ERK1/2 signaling pathway.

METHODSH9c2 cells oxidative injury was induced by 200 tmol/L H2O2 for 6 hours to establish the H2O2-induced injury model of H9c2 cells. The viability of H9c2 cells was detected using MTf method. Activity of lactate dehydrogenase(LDH), total-superoxide dismutase (T-SOD), manganese-superoxide dismutase (Mn-SOD) and content of MDA (malondialdehyde) in the culture medium were detected using colorimetric method. Western blot was performed to exam expression of p-ERK1/2 and ERK1/2 in H9c2 cells respectively.

RESULTSUnder 200 micromol/L H2O2 treatment for 6 hours, the vaibility of H9c2 cells was suitable for the following study. Compared with H2O2 group, the cell viability was increased significantly in AST10 + H2O2 and AST2O + H2O2 groups (P < 0.01). The activity of LDH in the culture medium was decreased significantly (P < 0.01). The activity of T-SOD and Mn-SOD was increased significantly (P < 0.01), the content of MDA was decreased significantly (P < 0.01). Treated with 10 mg/L or 20 mg/L of AST, expression of p-ERK1/2 in H9c2 cells injured from H2O2 was increased significantly (P < 0.01), when PD98059 (inhibitor of ERK1/2) was added, the effects of AST were cancelled.

CONCLUSIONAST protects H9c2 cells against H2O2-induced oxidative injury partly through ERK1/2 signaling pathway.

Animals ; Antioxidants ; pharmacology ; Cell Line ; Hydrogen Peroxide ; toxicity ; MAP Kinase Signaling System ; physiology ; Myoblasts, Cardiac ; drug effects ; metabolism ; pathology ; Oxidative Stress ; drug effects ; Protective Agents ; pharmacology ; Rats ; Saponins ; pharmacology ; Triterpenes ; pharmacology

BACKGROUNDTissue-engineered bioartificial muscle-based gene therapy represents a promising approach for the treatment of heart diseases. Experimental and clinical studies suggest that systemic administration of insulin-like growth factor-1 (IGF-1) protein or overexpression of IGF-1 in the heart exerts a favorable effect on cardiovascular function. This study aimed to investigate a chronic stage after myocardial infarction (MI) and the potential therapeutic effects of delivering a human IGF-1 gene by tissue-engineered bioartificial muscles (BAMs) following coronary artery ligation in Sprague-Dawley rats.

METHODSLigation of the left coronary artery or sham operation was performed. Primary skeletal myoblasts were retrovirally transduced to synthesize and secrete recombinant human insulin-like growth factor-1 (rhIGF-1), and green fluorescent protein (GFP), and tissue-engineered into implantable BAMs. The rats that underwent ligation were randomly assigned to 2 groups: MI-IGF group (n = 6) and MI-GFP group (n = 6). The MI-IGF group received rhIGF-secreting BAM (IGF-BAMs) transplantation, and the MI-GFP group received GFP-secreting BAM (GFP-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: S-IGF group (n = 6) and S-GFP group (n = 6). The S-IGF group underwent IGF-1-BAM transplantation, and S-GFP group underwent GFP-BAM transplantation. IGF-1-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats after two weeks of operation was performed. Four weeks after the treatment, hemodynamics was performed. IGF-1 was measured by radioimmunoassay, and then the rats were sacrificed and ventricular samples were subjected to immunohistochemistry. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of bax and Bcl-2. TNF-α and caspase 3 expression in myocardium was examined by Western blotting.

RESULTSPrimary rat myoblasts were retrovirally transduced to secrete rhIGF-1 and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted consistent levels of hIGF (0.4 - 1.2 µg×BAM(-1)×d(-1)). When implanted into syngeneic rat, IGF-BAMs secreted and delivered rhIGF. Four weeks after therapy, the hemodynamics was improved significantly in MI rats treated with IGF-BAMs compared with those treated with GFP-BAMs. The levels of serum IGF-1 were increased significantly in both MI and sham rats treated with IGF-BAM. The mRNA expression of bax was lower and Bcl-2 expression was higher in MI-IGF group than MI-GFP group (P < 0.05). Western blotting assay showed TNF-α and caspase 3 expression was lower in MI-IGF group than MI-GFP group after therapy.

CONCLUSIONSrhIGF-1 significantly improves left ventricular function and suppresses cardiomyocyte apoptosis in rats with chronic heart failure. Genetically modified tissue-engineered BAMs provide a method delivering recombinant protein for the treatment of heart failure.

Animals ; Apoptosis ; Caspase 3 ; analysis ; Desmin ; analysis ; Genetic Therapy ; Heart Failure ; pathology ; physiopathology ; therapy ; Insulin-Like Growth Factor I ; genetics ; secretion ; Myoblasts, Skeletal ; metabolism ; Myocytes, Cardiac ; pathology ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; secretion ; Retroviridae ; genetics ; Tissue Engineering ; Tumor Necrosis Factor-alpha ; analysis ; Ventricular Function, Left

BACKGROUND: A critical shortage of donor organs has necessitated an investigation of new strategies to increase the availability of additional organs available for human transplantation. We investigated the amount of apoptosis and expression of GADD45beta in two groups, a GADD45beta-transfected group and untransfected group. MATERIAL AND METHOD: The experimental groups consist of a control group (normal H9C2 cell line) and GADD45beta-transfected group. After injury of the each group, we evaluated the expression of GADD45beta and the level of apoptosis in each group. RESULT: There was a significant increase in the expression of GADD45beta in the GADD45beta-transfected group at 1 hour, 2 hours, and 3 hours after stimuli as compared with the control group. The amount of cardiac myoblast cell line apoptosis was significantly lower in the GADD45beta-transfected group as compared with the control group. The concentration of annexin in the GADD45beta-transfected group was significantly lower than that of the control group after cell injury. CONCLUSION: Transfection of a rat myoblast cell line with the GADD45beta gene results in decreased susceptibility to cell injury of human serum.
Animals ; Apoptosis ; Cell Line ; Humans ; Myoblasts ; Myoblasts, Cardiac ; Rats ; Tissue Donors ; Transfection ; Transplantation, Heterologous ; Transplants

Curcumin is a polyphenolic compound possessing interesting anti-inflammatory and antioxidant properties and has the ability to induce the defensive protein heme oxygenase-1 (HO-1). The objective of this study was to investigate whether curcumin protects against cold storage-mediated damage of human adult atrial myoblast cells (Girardi cells) and to assess the potential involvement of HO-1 in this process. Girardi cells were exposed to either normothermic or hypothermic conditions in Celsior preservation solution in the presence or absence of curcumin. HO-1 protein expression and heme oxygenase activity as well as cellular damage were assessed after cold storage or cold storage followed by re-warming. In additional experiments, an inhibitor of heme oxygenase activity (tin protoporphyrin IX, micrometer) or siRNA for HO-1 were used to investigate the participation of HO-1 as a mediator of curcumin- induced effects. Treatment with curcumin produced a marked induction of cardiac HO-1 in normothermic condition but cells were less responsive to the polyphenolic compound at low temperature. Cold storage-induced damage was markedly reduced in the presence of curcumin and HO-1 contributed to some extent to this effect. Thus, curcumin added to Celsior preservation solution effectively prevents the damage caused by cold- storage; this effect involves the protective enzyme HO-1 but also other not yet identified mechanisms.
Cell Death/drug effects ; Cell Survival/drug effects ; Cells, Cultured ; Cold Temperature ; *Cryopreservation ; Cryoprotective Agents/pharmacology ; Curcumin/*pharmacology ; Gene Expression Regulation, Enzymologic/drug effects ; Heme Oxygenase-1/genetics/metabolism ; Hemin/pharmacology ; Humans ; Hydrogen Peroxide/pharmacology ; Myoblasts, Cardiac/*drug effects/*pathology ; RNA, Messenger/genetics/metabolism

AIMTo investigate whether AcSDKP can inhibit proliferation and collagen synthesis in cultured rat cardiac fibroblasts mediated by PDGF.

METHODSNeonatal rat cardiac fibroblasts were isolated. The cell proliferation was observed by 3H-proline incorporation assay.

RESULTSOn the culture of 0.4% FBS, PDGF stimulated cardiac fibroblasts proliferation and collagen synthesis with a dose-dependent manner at the concentrations from 1 ng/ml to 20 ng/ml, in which 10 ng/ml PDGF reached its peak. AcSDKP at the concentration from 10(-10) mol/L to 10(-8) mol/L could inhibit cardiac fibroblasts proliferation and collagen synthesis mediated by PDGF. 10(-9) mol/L AcSDKP attained its peak on inhibiting cardiac fibroblasts proliferation and collagen synthesis.

CONCLUSIONAcSDKP can inhibit proliferation and collagen synthesis in cultured rat cardiac fibroblasts mediated by PDGF.

Animals ; Cell Proliferation ; Cells, Cultured ; Collagen ; biosynthesis ; Fibroblasts ; cytology ; drug effects ; metabolism ; Myoblasts, Cardiac ; cytology ; drug effects ; metabolism ; Oligopeptides ; pharmacology ; Platelet-Derived Growth Factor ; pharmacology ; Rats ; Rats, Wistar

AIMTo investigate the effects of pravastatin on endothelin(ET) expression induced by aldosterone in cultured neonatal rat cardiac fibroblasts.

METHODSET concentration in conditioned medium was measured by radioimmunoassay, intracellular ET-1 level was evaluated by flow cytometry, and the expression of preproendothelin-1 (ppET-1) was detected and quantified using reverse transcriptase-polymerase chain reaction (RT-PCR) method.

RESULTSThe cardiac fibroblasts, treated with aldosterone at 107 mol/L, significantly up-regulated ppET-1 mRNA expression, as well as ET-1 synthesis and release. Pravastatin (10(-5), 10(-4), 10(-3) mol/L) dose-dependently blocked these effects. In contrast, pravastatin-induced inhibitory effects were reversed in the presence of mevalonate.

CONCLUSIONPravastatin down-regulated ppET-1 mRNA expression, as well as ET-1 synthesis and release induced by aldosterone in a process specifically related to mevalonate in cardiac fibroblasts.

Aldosterone ; metabolism ; Animals ; Cells, Cultured ; Endothelins ; metabolism ; Fibroblasts ; drug effects ; metabolism ; Myoblasts, Cardiac ; drug effects ; metabolism ; Pravastatin ; pharmacology ; Rats ; Rats, Sprague-Dawley

Aldosterone ; pharmacology ; Animals ; Animals, Newborn ; Cells, Cultured ; Endothelins ; metabolism ; Myoblasts, Cardiac ; drug effects ; secretion ; Nitric Oxide ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To clarify the effect of nucleolin on the proliferation and apoptosis in C2C12 cells. METHODS: After inhibiting the expression of nucleolin using antisense oligonucleotides, the cellular proliferation was determined by MTT, and the apoptosis was detected by flow cytometry (FCM) assays and DNA ladder assays. RESULTS: After being transfected with antisense oligonucleotides for 24 hours, Western blotting showed that the expression of nucleolin was repressed significantly. In cells treated with antisense oligonucleotides, the cellular proliferation was obviously inhibited; the apoptotic cell increased significantly; and the "DNA ladder" was clearly observed. But the sense and random oligonucleotides had no effect on the cellular proliferation and apoptosis. CONCLUSION The down-regulation of nucleolin can inhibit the cellular proliferation and initiate the apoptosis in C2C12cells.
Animals ; Apoptosis ; physiology ; Cell Proliferation ; Cells, Cultured ; Down-Regulation ; Mice ; Myoblasts ; cytology ; Myocytes, Cardiac ; cytology ; Oligonucleotides, Antisense ; Phosphoproteins ; biosynthesis ; genetics ; RNA-Binding Proteins ; biosynthesis ; genetics ; Transfection

OBJECTIVE: To observe whether HSP70 could protect against H2O2-induced apoptosis in C2C12 myogenic cells by inhibiting Smac release from the mitochondria. METHODS: HSP70 gene and full length Smac gene was transiently transfected in C2C12 myogenic cells by lipofectamine and the protein levels of HSP70 and Smac were analysed by Western blotting. Hoechst 33 258 staining was used to examine cell morphological changes and to calculate percentage of apoptotic nuclei. DNA ladder pattern on agarose gel electrophoresis was used to observe the DNA fragmentation. Activities of caspase-3 and caspase-9 were assayed with Western blotting. The release of Smac from the mitochondria to the cytoplasm was observed by immunofluorescence. RESULTS: H2O2 ( 0.5 mmol/L ) activated caspase-3, caspase-9 8 h after the treatment and specific morphological changes of apoptosis 12 h after the treatment, and overexpression of Smac significantly promoted H2O2-induced activation of caspase-3, caspase-9 and apoptosis in C2C12 myogenic cells. HSP70 overexpression significantly inhibited H2O2-induced and Smac-promoted apoptosis, as shown by no specific DNA ladder pattern in agarose gel electrophoresis, decrease of percentage of apoptotic nuclei, and marked inactivation of caspase-3 and caspase-9. HSP70 could inhibit the release of Smac from the mitochondria to the cytoplasm 2 h after the treatment by H2O2. CONCLUSION HSP70 inhibits Smac release from the mitochondria and protects against H2O2-induced apoptosis in C2C12 myogenic cells.
Apoptosis ; drug effects ; Apoptosis Regulatory Proteins ; Cells, Cultured ; HSP70 Heat-Shock Proteins ; pharmacology ; Humans ; Hydrogen Peroxide ; Intracellular Signaling Peptides and Proteins ; metabolism ; Mitochondria, Heart ; drug effects ; metabolism ; Mitochondrial Proteins ; antagonists & inhibitors ; metabolism ; Myoblasts ; metabolism ; Myocytes, Cardiac ; drug effects ; metabolism