OBJECTIVE: To investigate the role of myosin heavy chain 9 (MYH9) in regulation of cell proliferation, apoptosis, and cisplatin sensitivity of non-small cell lung cancer (NSCLC). METHODS: Six NSCLC cell lines (A549, H1299, H1975, SPCA1, H322, and H460) and a normal bronchial epithelial cell line (16HBE) were examined for MYH9 expression using Western blotting. Immunohistochemical staining was used to detect MYH9 expression in a tissue microarray containing 49 NSCLC and 43 adjacent tissue specimens. MYH9 knockout cell models were established in H1299 and H1975 cells using CRISPR/Cas9 technology, and the changes in cell proliferation cell were assessed using cell counting kit-8 (CCK8) and clone formation assays; Western blotting and flow cytometry were used to detect apoptosis of the cell models, and cisplatin sensitivity of the cells was evaluated using IC50 assay. The growth of tumor xenografts derived from NSCLC with or without MYH9 knockout was observed in nude mice. RESULTS: MYH9 expression was significantly upregulated in NSCLC (P < 0.001), and the patients with high MYH9 expression had a significantly shorter survival time (P=0.023). In cultured NSCLC cells, MYH9 knockout obviously inhibited cell proliferation (P < 0.001), promoted cell apoptosis (P < 0.05), and increased their chemosensitivity of cisplatin. In the tumor-bearing mouse models, the NSCLC cells with MYH9 knockout showed a significantly lower growth rate (P < 0.05). Western blotting showed that MYH9 knockout inactivated the AKT/c- Myc axis (P < 0.05) to inhibit the expression of BCL2- like protein 1 (P < 0.05), promoted the expression of BH3- interacting domain death agonist and the apoptosis regulator BAX (P < 0.05), and activated apoptosis-related proteins caspase-3 and caspase-9 (P < 0.05). CONCLUSION High expression of MYH9 contributes to NSCLC progression by inhibiting cell apoptosis via activating the AKT/c-Myc axis.
Animals ; Humans ; Mice ; Apoptosis ; Carcinoma, Non-Small-Cell Lung/metabolism* ; Cell Line, Tumor ; Cell Proliferation ; Cisplatin/pharmacology* ; Cytoskeletal Proteins/metabolism* ; Lung Neoplasms/metabolism* ; Mice, Nude ; Myosin Heavy Chains/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Signal Transduction

Objective: To investigate the effects of non-muscle myosin Ⅱ (NMⅡ) gene silenced bone marrow-derived mesenchymal stem cells (BMMSCs) on pulmonary extracellular matrix (ECM) and fibrosis in rats with acute lung injury (ALI) induced by endotoxin/lipopolysaccharide (LPS). Methods: The experimental research methods were adopted. Cells from femur and tibial bone marrow cavity of four one-week-old male Sprague-Dawley rats were identified as BMMSCs by flow cytometry, and the third passage of BMMSCs were used in the following experiments. The cells were divided into NMⅡ silenced group transfected with pHBLV-U6-ZsGreen-Puro plasmid containing small interference RNA sequence of NMⅡ gene, vector group transfected with empty plasmid, and blank control group without any treatment, and the protein expression of NMⅡ at 72 h after intervention was detected by Western blotting (n=3). The morphology of cells was observed by an inverted phase contrast microscope and cells labeled with chloromethylbenzoine (CM-DiⅠ) in vitro were observed by an inverted fluorescence microscope. Twenty 4-week-old male Sprague-Dawley rats were divided into blank control group, ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group according to the random number table, with 5 rats in each group. Rats in blank control group were not treated, and rats in the other 3 groups were given LPS to induce ALI. Immediately after modeling, rats in ALI alone group were injected with 1 mL normal saline via tail vein, rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were injected with 1×10⁷/mL BMMSCs and NMⅡ gene silenced BMMSCs of 1 mL labelled with CM-DiⅠ via tail vein, and rats in blank control group were injected with 1 mL normal saline via tail vein at the same time point, respectively. At 24 h after intervention, the lung tissue was collected to observe intrapulmonary homing of the BMMSCs by an inverted fluorescence microscope. Lung tissue was collected at 24 h, in 1 week, and in 2 weeks after intervention to observe pulmonary inflammation by hematoxylin eosin staining and to observe pulmonary fibrosis by Masson staining, and the pulmonary fibrosis in 2 weeks after intervention was scored by modified Ashcroft score (n=5). The content of α-smooth muscle actin (α-SMA), matrix metalloproteinase 2 (MMP-2), and MMP-9 was detected by immunohistochemistry in 2 weeks after intervention (n=3), the activity of superoxide dismutase (SOD), malondialdehyde, myeloperoxidase (MPO) was detected by enzyme-linked immunosorbent assay at 24 h after intervention (n=3), and the protein expressions of CD11b and epidermal growth factor like module containing mucin like hormone receptor 1 (EMR1) in 1 week after intervention were detected by immunofluorescence staining (n=3). Data were statistically analyzed with one-way analysis of variance, Bonferroni method, and Kruskal-Wallis H test. Results: At 72 h after intervention, the NMⅡprotein expression of cells in NMⅡ silenced group was significantly lower than those in blank control group and vector group (with P values <0.01). BMMSCs were in long spindle shape and grew in cluster shaped like vortexes, which were labelled with CM-DiⅠ successfully in vitro. At 24 h after intervention, cell homing in lung of rats in ALI+NMⅡ silenced BMMSC group was more pronounced than that in ALI+BMMSC group, while no CM-DiⅠ-labelled BMMSCs were observed in lung of rats in blank control group and ALI alone group. There was no obvious inflammatory cell infiltration in lung tissue of rats in blank control group at all time points, while inflammatory cell infiltration in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly less than that in ALI alone group at 24 h after intervention, and alveolar wall turned to be thinner and a small amount of congestion in local lung tissue appeared in rats of the two groups in 1 week and 2 weeks after intervention. In 1 week and 2 weeks after intervention, collagen fiber deposition in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group was significantly aggravated compared with that in blank control group, while collagen fiber deposition in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly improved compared with that in ALI alone group. In 2 weeks after intervention, modified Ashcroft scores for pulmonary fibrosis of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were 2.36±0.22, 1.62±0.16, 1.06±0.26, respectively, significantly higher than 0.30±0.21 in blank control group (P<0.01). Modified Ashcroft scores for pulmonary fibrosis of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly lower than that in ALI alone group (P<0.01), and modified Ashcroft score for pulmonary fibrosis of rats in ALI+NMⅡ silenced BMMSC group was significantly lower than that in ALI+BMMSC group (P<0.01). In 2 weeks after intervention, the content of α-SMA in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly decreased compared with that in ALI alone group (P<0.05 or P<0.01). The content of MMP-2 in lung tissue of rats in the 4 groups was similar (P>0.05). The content of MMP-9 in lung tissue of rats in ALI alone group was significantly increased compared with that in blank control group (P<0.01), and the content of MMP-9 in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group (P<0.01). At 24 h after intervention, the activity of malondialdehyde, SOD, and MPO in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in blank control group (P<0.01), the activity of malondialdehyde in lung tissue of rats in ALI+NMⅡ silenced BMMSC group and the activity of SOD in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in ALI alone group (P<0.05 or P<0.01), and the activity of SOD in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group (P<0.01). The activity of MPO in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group (P<0.01), and the activity of MPO in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group (P<0.01). In 1 week after intervention, the protein expression of CD11b in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly increased compared with those in the other three groups (P<0.05 or P<0.01), while the protein expressions of EMR1 in lung tissue of rats in the four groups were similar (P>0.05). Conclusions: Transplantation of NMⅡ gene silenced BMMSCs can significantly improve the activity of ECM components in the lung tissue in LPS-induced ALI rats, remodel its integrity, and enhance its antioxidant capacity, and alleviate lung injury and pulmonary fibrosis.
Acute Lung Injury/therapy* ; Animals ; Bone Marrow ; Collagen/metabolism* ; Endotoxins ; Extracellular Matrix ; Lipopolysaccharides/adverse effects* ; Lung ; Male ; Malondialdehyde/metabolism* ; Matrix Metalloproteinase 2/metabolism* ; Matrix Metalloproteinase 9/metabolism* ; Mesenchymal Stem Cells/metabolism* ; Myosin Type II/metabolism* ; Pulmonary Fibrosis ; Rats ; Rats, Sprague-Dawley ; Saline Solution/metabolism* ; Superoxide Dismutase/metabolism*

Myosin light chain 9 (MYL9) is a regulatory light chain of myosin, which plays an important role in various biological processes including cell contraction, proliferation and invasion. MYL9 expresses abnormally in several malignancies including lung cancer, breast cancer, prostate cancer, malignant melanoma and others, which is closely related to the poor prognosis, but the clinical significance for its expression varies with different types of cancer tissues. Further elucidating the molecular mechanism of MYL9 in various types of malignant tumor metastasis is of great significance for cancer prevention and treatment. At the same time, as a molecular marker and potential target, MYL9 may have great clinical value in the early diagnosis, prognosis prediction, and targeted treatment of malignant tumors.
Biomarkers ; Humans ; Lung Neoplasms ; Male ; Myosin Light Chains/metabolism* ; Prognosis ; Prostatic Neoplasms

This paper was aimed to investigate the inhibitory effect of aconitine(AC) on angiotensin Ⅱ(Ang Ⅱ)-induced H9 c2 cell hypertrophy and explore its mechanism of action. The model of hypertrophy was induced by Ang Ⅱ(1×10-6 mol·L-1),and cardiomyocytes were incubated with different concentrations of AC. Western blot was used to quantify the protein expression levels of atrial natriuretic peptide(ANP),brain natriuretic peptide(BNP),β-myosin heavy chain(β-MHC),and α-smooth muscle actin(α-SMA). Real-time quantitative PCR(qRT-PCR) was used to quantify the mRNA expression levels of cardiac hypertrophic markers ANP,BNP and β-MHC. In addition,the fluorescence intensity of the F-actin marker,an important component of myofibrils,was detected by using laser confocal microscope. AC could significantly reverse the increase of total protein content in H9 c2 cells induced by Ang Ⅱ; qRT-PCR results showed that AC could significantly inhibit the ANP,BNP and β-MHC mRNA up-regulation induced by AngⅡ. Western blot results showed that AC could significantly inhibit the ANP,BNP and β-MHC protein up-regulation induced by AngⅡ. In addition,F-actin expression induced by Ang Ⅱ could be inhibited by AC,and multiple indicators of cardiomyocyte hypertrophy induced by Ang Ⅱ could be down-regulated,indicating that AC may inhibit cardiac hypertrophy by inhibiting the expression of hypertrophic factors,providing new clues for exploring the cardiovascular protection of AC.
Aconitine ; pharmacology ; Actins ; metabolism ; Angiotensin II ; Atrial Natriuretic Factor ; metabolism ; Cardiac Myosins ; metabolism ; Cardiomegaly ; Cells, Cultured ; Humans ; Hypertrophy ; Myocytes, Cardiac ; drug effects ; Myosin Heavy Chains ; metabolism ; Natriuretic Peptide, Brain ; metabolism

OBJECTIVE: To investigate the effects of hydrogen sulfide (HS) on the negatively regulation of cardiomyocyte hypertrophy and the relationship between the effect of HS with miRNA-133a-mediated Ca/calcineurin/NFATc4 signal pathway. METHODS: Cardiomyocyte hypertrophy was induced by isoproterenol (ISO). The cell surface area was measured by image analysis system (Leica). The expression of brain natriuretic peptide(BNP), β-myosin heavy chain(β-MHC), cystathionase (CSE), miRNA-133a, calcineurin (CaN) were detected by qRT-PCR. The protein expressions of CaN、nuclear factors of activated T cells (NFATc4) were detected by Western blot. The concentration of HS in the cardiomyocyte was detected by Elisa. The concentration of intracellular calcium was measured by calcium imaging using confocal microscope. The nuclear translocation of NFATc4 was checked by immuno-fluorescence cell staining technique. RESULTS: ①The level of system of CSE/HS and expression of miRNA-133a were significantly reduced in cardiomyocyte hypertrophy. Pretreatment with NaHS increased the concentration of HS and the expression of miRNA-133a mRNA in cardiomyocytes, and suppressed cardiomyocyte hypertrophy. ②The concentration of intracellular calcium, the expression of CaN and nulear protein NFATc4 were significantly increased, and the nuclear translocation of NFATc4 were obviously enhanced in cardiomyocyte hypertrophy. NaHS pretreatment markedly inhibited these effects of ISO induced cardiomyocyte hypertrophy. ③Application of antagomir-133a reversed the inhibitory effects of NaHS on cardiomyocyte hypertrophy, and increased the influx of intracellular calcium, and elevated the expression of CaN and nuclear protein NFATc4, and enhanced the nuclear translocation of NFATc4. CONCLUSIONS HS can negatively regulate cardiomyocyte hypertrophy. The effects might be associated with HS increasing expression of miRNA-133a and inhibiting inactivation of Ca/calcineurin/NFATc4 signal pathway.
Animals ; Calcineurin ; metabolism ; Cardiomegaly ; chemically induced ; metabolism ; Cells, Cultured ; Cystathionine gamma-Lyase ; metabolism ; Hydrogen Sulfide ; metabolism ; MicroRNAs ; metabolism ; Myocytes, Cardiac ; metabolism ; Myosin Heavy Chains ; metabolism ; NFATC Transcription Factors ; metabolism ; Natriuretic Peptide, Brain ; metabolism ; Nerve Tissue Proteins ; metabolism ; Rats ; Signal Transduction

BackgroundOutflow tract (OFT) septation defects are a common cause of congenital heart disease. Numerous studies have focused on the septation mechanism of the OFT, but have reported inconsistent conclusions. This study, therefore, aimed to investigate the septation of the aortic sac and the OFT in the early embryonic human heart.

MethodsSerial sections of 27 human embryonic hearts from Carnegie stage (CS) 10 to CS19 were immunohistochemically stained with antibodies against α-smooth muscle actin (α-SMA) and myosin heavy chain.

ResultsAt CS10-CS11, the OFT wall was an exclusively myocardial structure that was continuous with the aortic sac at the margin of the pericardial cavity. From CS13 onward, the OFT was divided into nonmyocardial and myocardial portions. The cushion formed gradually, and its distal border with the OFT myocardium was consistently maintained. The aortic sac between the fourth and sixth aortic arch arteries was degenerated. At CS16, the α-SMA-positive aortopulmonary septum formed and fused with the two OFT cushions, thus septating the nonmyocardial portion of the OFT into two arteries. At this stage, the cushions were not fused. At CS19, the bilateral cushions were fused to septate the myocardial portion of the OFT.

ConclusionsData suggest that the OFT cushion is formed before the aortopulmonary septum is formed. Thus, the OFT cushion is not derived from the aortopulmonary septum. In addition, the nonmyocardial part of the OFT is septated into the aorta and pulmonary trunk by the aortopulmonary septum, while the main part of the cushion fuses and septates the myocardial portion of the OFT.

Actins ; metabolism ; Alkaline Phosphatase ; metabolism ; Aorta ; embryology ; Heart ; embryology ; Heart Valves ; embryology ; Humans ; Immunohistochemistry ; Myosin Heavy Chains ; metabolism

OBJECTIVETo investigate whether phenotypic modulation of bladder smooth muscle occurs in diabetic rats.

METHODSThirty-two male SD rats were randomly assigned into diabetic group and control group. Diabetic rat models were established by a single intraperitoneal injection of streptozotocin (60 mg/kg). Nine weeks later, the bladder tissues of the rats were examined for structural changes using HE and Masson's trichrome staining , and the expressions of myocardin, α-SMA, and SMMHC in bladder smooth muscles were detected with RT-PCR and Western blotting.

RESULTSCompared with the control group, the diabetic rats showed obvious polydipsia and polyuria with significantly increased collagenous fibers and lowered expressions of myocardin, α-SMA, and SMMHC in the bladder tissue (P<0.05).

CONCLUSIONs In rats at 9 weeks after diabetic model establishment, phenotypic transition of the bladder smooth muscles occurs to cause bladder contractile dysfunction, which may play an important role in the pathology of diabetic bladder dysfunction.

Actins ; metabolism ; Animals ; Diabetes Mellitus, Experimental ; physiopathology ; Male ; Muscle Contraction ; Muscle, Smooth ; physiopathology ; Myosin Heavy Chains ; metabolism ; Nuclear Proteins ; metabolism ; Phenotype ; Rats ; Rats, Sprague-Dawley ; Streptozocin ; Trans-Activators ; metabolism ; Urinary Bladder ; physiopathology

OBJECTIVE: To investigate the effect of hydrogen sulfide (H2S) on cardiac myosin light chain kinase (MLCK) expression in diabetic rats.
 METHODS: A total of 32 male SD rats were randomly divided into a normal control group (NC group), a diabetic control group (DM), a NaHS treatment group (DM+NaHS) and a NaHS group (NaHS) (n=8 in each group). Intraperitoneal injection of streptozotocin was utilized to establish Type 1 diabetic rat model. The diabetic rats in the DM+NaHS and NaHS groups were intraperitoneally injected with 28 μmol/kg NaHS solution. Eight weeks later, the ventricular hemodynamic parameters, the ratio of heart weight/body weight (HW/BW ratio), the levels of lactate dehydrogenase (LDH) and creatine kinase MB isozyme (CK-MB) in serum were determined. The ultrastructures of myocardium were observed under electron microscopy. The expressions of MLCK mRNA and protein level in myocardium were detected by RT-PCR and Western blot, respectively.
 RESULTS: Compared with the NC group, there was no significant difference in the various indexes in the NaHS group (all P>0.05). The function of left ventricular contract and relaxation were decreased obviously in diabetic rats, while the HW/BW ratio was increased (all P<0.01). The levels of LDH and CK-MB were increased (both P<0.01) in serum, while the levels of MLCK mRNA and protein were decreased significantly (both P<0.01) in myocardial tissues. Compared with the DM group, the left ventricular hemodynamic parameters and myocardial ultrastructure damage were improved in the DM+NaHS group, while the HW/BW ratio was decreased (all P<0.05). The levels of LDH and CK-MB were decreased (both P<0.01), while the levels of MLCK mRNA and protein were increased significantly (both P<0.01).
 CONCLUSION H2S can protect myocardium in diabetic rats, which may be associated with upregulation of cardiac MLCK.
Animals ; Cardiotonic Agents ; pharmacology ; Creatine Kinase, MB Form ; blood ; Diabetes Mellitus, Experimental ; drug therapy ; Heart ; drug effects ; Hemodynamics ; Hydrogen Sulfide ; pharmacology ; L-Lactate Dehydrogenase ; blood ; Male ; Myocardium ; ultrastructure ; Myosin-Light-Chain Kinase ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sulfides ; pharmacology ; Ventricular Function, Left ; drug effects

AMP-activated protein kinase (AMPK) is a metabolic sensor activated during metabolic stress and it regulates various enzymes and cellular processes to maintain metabolic homeostasis. We previously reported that activation of AMPK by glucose deprivation (GD) and leptin increases KATP currents by increasing the surface levels of KATP channel proteins in pancreatic beta-cells. Here, we show that the signaling mechanisms that mediate actin cytoskeleton remodeling are closely associated with AMPK-induced KATP channel trafficking. Using F-actin staining with Alexa 633-conjugated phalloidin, we observed that dense cortical actin filaments present in INS-1 cells cultured in 11 mM glucose were disrupted by GD or leptin treatment. These changes were blocked by inhibiting AMPK using compound C or siAMPK and mimicked by activating AMPK using AICAR, indicating that cytoskeletal remodeling induced by GD or leptin was mediated by AMPK signaling. AMPK activation led to the activation of Rac GTPase and the phosphorylation of myosin regulatory light chain (MRLC). AMPK-dependent actin remodeling induced by GD or leptin was abolished by the inhibition of Rac with a Rac inhibitor (NSC23766), siRac1 or siRac2, and by inhibition of myosin II with a myosin ATPase inhibitor (blebbistatin). Immunocytochemistry, surface biotinylation and electrophysiological analyses of KATP channel activity and membrane potentials revealed that AMPK-dependent KATP channel trafficking to the plasma membrane was also inhibited by NSC23766 or blebbistatin. Taken together, these results indicate that AMPK/Rac-dependent cytoskeletal remodeling associated with myosin II motor function promotes the translocation of KATP channels to the plasma membrane in pancreatic beta-cells.
AMP-Activated Protein Kinases/metabolism ; Actins/*metabolism ; Animals ; Cell Line ; Glucose/metabolism ; Insulin-Secreting Cells/*metabolism ; KATP Channels/*metabolism ; Leptin/metabolism ; Myosin Type II/*metabolism ; Phosphorylation ; Rats ; *Signal Transduction ; rac GTP-Binding Proteins/*metabolism

OBJECTIVETo study the effect of platelet-derived growth factor-BB (PDGFBBB) on rat corpus cavernosum smooth muscle (CCSM) cell proliferation, migration and phenotypic modulation and explore the underlying mechanisms.

METHODSWistar rat CCSM cells were obtained through a modified tissue culture method and identified by immunofluorescence assay. The effect of PDGFBB on the proliferation of CCSM cells was investigated using a CCK-8 kit and the optimum PDGFBB concentration for cell treatment was determined. CCSM cells were treated with vehicle or PDGF-BB at the optimum concentration, and the cell migration was examined using scratch assay; the mRNA expression of the transcription factor myocardin and the contractile phenotype markers αSMA and SMMHC in CCSM cells were determined by qRT-PCR at 24 h and 48 h. The protein expression of myocardin in CCSM cells incubated with PDGFBB for 0, 24 and 48 h was examined by Western blotting.

RESULTIn CCSM cell culture, 96.5%and 96% of the cells were positive for αSMA and smoothelin, respectively. PDGFBB at different concentrations markedly promoted the proliferation of CCSM cells; the optimum PDGFBB concentration for enhancing cell proliferation was 12.5 ng/mL, which induced the migration of CCSM cells and significantly reduced the mRNA expressions of myocardin, αSMA and SMMHC (P<0.01). Exposure to PDGFBB decreased the protein expression of myocardin as the exposure time extended (within 48 h).

CONCLUSIONCCSM cells of a high purity can be obtained by the modified tissue culture method. PDGFBB can promote the proliferation and migration of CCSM cells and cause a phenotypic conversion from the contractile to the synthetic type possibly by down-regulating myocardin.

Actins ; metabolism ; Animals ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Down-Regulation ; Male ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Myosin Heavy Chains ; metabolism ; Nuclear Proteins ; metabolism ; Penis ; cytology ; Phenotype ; Proto-Oncogene Proteins c-sis ; pharmacology ; RNA, Messenger ; Rats ; Rats, Wistar ; Trans-Activators ; metabolism