OBJECTIVE: To observe the effects of the "Zhibian" (BL54)-toward-"Shuidao" (ST28) acupuncture on key regulatory factors during mitochondrial apoptosis of testicular tissue in asthenozoospermia mice, and explore the potential mechanism of the protective effect of acupuncture on reproductive function. METHODS: Thirty C57BL/6 male mice were randomly divided into a blank group, a model group and an acupuncture group, 10 mice in each group. In the model and the acupuncture groups, the intraperitoneal injection of cyclophosphamide (30 mg•kg^-1•d^-1) was delivered for 7 days to prepare the asthenozoospermia model. After the success of modeling, the modeled mice in the acupuncture group were intervened with "Zhibian" (BL54)-toward-"Shuidao" (ST28) acupuncture, once daily and the needles were retained for 20 min. The duration of the intervention was 2 weeks. The general condition of each mouse was observed, and the body mass was recorded before modeling, after modeling and after intervention completion. After intervention, the testicular mass was recorded and the weight coefficient was calculated, and the mouse sperm quality was examined; the serum contents of testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were detected using ELISA, the morphology of testicular tissue was observed using HE, the mitochondrial ultra-microstructure of testicular tissue was observed under transmission electrone microscopy, the mitochondrial membrane potential level of testicular tissue was detected using JC-1 staining, the positive rate of apoptosis cell of testicular tissue was observed using TUNEL; and the mRNA and protein expression of b-cell lymphocytoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), cytochrome c (Cyt C), apoptotic protease-activating factor1 (Apaf-1), Caspase-9 and Caspase-3 of testicular tissue was detected using real-time quantitative fluorescence PCR and Western blot methods separately; and the positive expression of Cleaved Caspase-3 of the testicular tissue was detected using immunohistochemistry. RESULTS: Compared with the blank group, the mice were in listless spirits, had shaggy hairs, the reduced appetite and movement, and weight loss in the model group (P<0.01); the testicular mass and the weight coefficient decreased (P<0.01); the total number of sperms, sperm motility, and sperm viability were declined (P<0.01); while the levels of serum T, FSH, and LH were dropped (P<0.01). The morphology of seminiferous tubules in testicular tissue was abnormal, the number of spermatogenic cells and the number of mitochondria decreased, the inner mitochondrial crest was fractured and lost, and vacuoles appeared. The level of mitochondrial membrane potential was reduced (P<0.01); and the positive rate of apoptosis cell in testicular tissue increased (P<0.01). The mRNA and protein expression of Bax, Cyt C, Apaf-1, Caspase-9 and Caspase-3 was elevated (P<0.01, P<0.05), the mRNA and protein expression of Bcl-2 was dropped (P<0.01), and the average absorbance value of Cleaved Caspase-3 increased (P<0.01). When compared with the model group, in the acupuncture group, the general condition of mice was improved, the testicular mass and the weight coefficient elevated (P<0.01); the total number of sperms, sperm motility, and sperm viability increased (P<0.01); while the levels of serum T, FSH, and LH rose (P<0.01). The pathological morphology of testicular tissue and the inner mitochondrial ultra-microstructure were ameliorated, the level of mitochondrial membrane potential was elevated (P<0.01); the positive rate of apoptosis cell was reduced (P<0.01). The mRNA and protein expression of Bax, Cyt C, Apaf-1, Caspase-9 and Caspase-3 was dropped (P<0.01, P<0.05), the mRNA and protein expression of Bcl-2 elevated (P<0.05), and the average absorbance value of Cleaved Caspase-3 declined (P<0.01). CONCLUSION "Zhibian" (BL54)-toward- "Shuidao" (ST28) acupuncture may ameliorate mouse reproductive function by inhibiting mitochondrial apoptosis pathway, alleviating testicular tissue damage in the asthenospermia mice induced by cyclophosphamide.
Animals ; Male ; Mice ; Apoptosis ; Acupuncture Therapy ; Mitochondria/metabolism* ; Asthenozoospermia/genetics* ; Humans ; Testis/metabolism* ; Mice, Inbred C57BL ; Spermatozoa/metabolism* ; Acupuncture Points ; Sperm Motility ; Testosterone/blood* ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Caspase 3/genetics* ; Follicle Stimulating Hormone/blood* ; Reproduction ; Cytochromes c/genetics* ; bcl-2-Associated X Protein/genetics* ; Apoptotic Protease-Activating Factor 1/genetics*

This study aims to elucidate the role and mechanism of clematichinenoside AR(CAR) in protecting bone marrow mesenchymal stem cells(BMSCs) from hypoxia-induced apoptosis. BMSCs were isolated by the bone fragment method and identified by flow cytometry. Cells were cultured under normal conditions(37℃, 5% CO_2) and hypoxic conditions(37℃, 90% N_2, 5% CO_2) and treated with CAR. The BMSCs were classified into eight groups: control(normal conditions), CAR(normal conditions + CAR), hypoxia 24 h, hypoxia 24 h + CAR, hypoxia 48 h, hypoxia 48 h + CAR, hypoxia 72 h, and hypoxia 72 h + CAR. The cell counting kit-8(CCK-8) assay and terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) were employed to measure cell proliferation and apoptosis, respectively. The number of mitochondria and mitochondrial membrane potential were measured by MitoTracker®Red CM-H2XRo staining and JC-1 staining, respectively. The level of reactive oxygen species(ROS) was measured with the DCFH-DA fluorescence probe. The protein levels of B-cell lymphoma-2 associated X protein(BAX), caspase-3, and optic atrophy 1(OPA1) were determined by Western blot. The results demonstrated that CAR significantly increased cell proliferation. Compared with the control group, the hypoxia groups showed increased apoptosis rates, reduced mitochondria, elevated ROS levels, decreased mitochondrial membrane potential, upregulated expression of BAX and caspase-3, and downregulated expression of OPA1. In comparison to the corresponding hypoxia groups, CAR intervention significantly decreased the apoptosis rate, increased mitochondria, reduced ROS levels, elevated mitochondrial membrane potential, downregulated the expression of BAX and caspase-3, and upregulated the expression of OPA1. Therefore, it can be concluded that CAR may exert an anti-apoptotic effect on BMSCs under hypoxic conditions by regulating OPA1 to maintain mitochondrial homeostasis.
Mesenchymal Stem Cells/metabolism* ; Apoptosis/drug effects* ; Mitochondria/metabolism* ; Animals ; Rats ; Cell Hypoxia/drug effects* ; Homeostasis/drug effects* ; Reactive Oxygen Species/metabolism* ; Rats, Sprague-Dawley ; Membrane Potential, Mitochondrial/drug effects* ; Saponins/pharmacology* ; Caspase 3/genetics* ; Male ; bcl-2-Associated X Protein/genetics* ; Bone Marrow Cells/metabolism* ; Cell Proliferation/drug effects* ; Protective Agents/pharmacology* ; Cells, Cultured

Objective To explore the mechanism of lncRNA-BC200 (BC200) targeting the ubiquitination of Beta-site APP cleaving enzyme 1 (BACE1) and regulating the repair of nerve cell injury. Methods Mouse hippocampal neuron cell line HT22 was divided into four groups: control group, oxygen-glucose deprivation/reoxygenation(OGD/R) group, OGD/R+si-NC group and OGD/R+si-BC200 group. In order to further explore the relationship between BC200 and BACE1, HT22 cells were divided into four groups: OGD/R group, OGD/R+si-BC200 group, OGD/R+si-BC200+NC group and OGD/R+si-BC200+ BACE1 group. Twenty male C57BL/6J mice were randomly assigned to the following four groups: control group, middle cerebral artery occlusion (MCAO) group, MCAO+si-BC200 group and MCAO+si-BC200+BACE1 group. The mRNA expression levels of BC200 and BACE1 in cells were measured by real-time quantitative reverse transcription polymerase chain reaction. The expressions of c-caspase-3, B-cell lymphoma 2 (Bcl2), Bcl2 associated X protein(BAX) and BACE1 were detected by western blot, and the apoptotic cells were detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) test. Results Compared with the control group, the activity of HT22 cells in OGD/R group decreased significantly, and the percentage of apoptotic cells increased significantly. Compared with OGD/R+si-NC group, the activity of HT22 cells in OGD/R+si-BC200 group increased significantly, and the percentage of apoptotic cells decreased significantly. Compared with the control group, the expression of BACE1 protein in HT22 cells in OGD/R group was significantly enhanced. Compared with OGD/R+si-NC group, the expression of BACE1 protein in HT22 cells in OGD/R+si-BC200 group decreased significantly. It was observed that after OGD/R treatment, the ubiquitination level of BACE1 decreased significantly and the expression of BACE1 protein increased significantly. After transfection with si-BC200, the ubiquitination level of BACE1 protein increased significantly, while the expression of BACE1 protein decreased significantly. Compared with OGD/R+si-BC200+NC group, the percentage of apoptotic cells, the expression of c-caspase-3 and Bax protein in HT22 cells in OGD/R+si-BC200+BACE1 group increased significantly, and the expression of Bcl2 protein decreased significantly. Compared with the control group, the number of cerebral infarction areas and TUNEL positive cells in MCAO group increased significantly, and the survival number of neurons decreased significantly. Compared with the MCAO group, the number of cerebral infarction areas and TUNEL positive cells in MCAO+si-BC200 group decreased significantly, and the survival number of neurons increased significantly, while the addition of BACE1 reversed the improvement of si-BC200 transfection. Conclusion The combination of BC200 and BACE1 inhibit the ubiquitination of BACE1, and participate in mediating the expression enhancement of BACE1 induced by OGD/R. Specific blocking of BC200/BACE1 axis may be a potential therapeutic target to protect neurons from apoptosis induced by cerebral ischemia/reperfusion.
Animals ; Amyloid Precursor Protein Secretases/genetics* ; RNA, Long Noncoding/physiology* ; Aspartic Acid Endopeptidases/genetics* ; Male ; Neurons/pathology* ; Mice ; Mice, Inbred C57BL ; Apoptosis/genetics* ; Ubiquitination ; Cell Line ; Hippocampus/metabolism* ; bcl-2-Associated X Protein/genetics* ; Caspase 3/genetics* ; Infarction, Middle Cerebral Artery/metabolism*

OBJECTIVE: To study the expression of SPOP in patients with acute myeloid leukemia (AML) and its effect on proliferation, apoptosis and cycle of AML cells. METHODS: RT-qPCR was used to detect the expression of SPOP mRNA in bone marrow samples of patients with newly diagnosed AML and normal controls. The stable overexpression of SPOP in AML cell lines THP-1 and U937 were constructed by liposome transfection. The effect of SPOP on cell proliferation was detected by CCK-8, and the effect of SPOP on apoptosis and cell cycle was detected by flow cytometry. The expressions of anti-apoptotic protein Bcl-2 and apoptotic protein Bax, Caspase3 were detected by Western blot. RESULTS: The median expression level of SPOP mRNA in normal control group was 0.993 1(0.6303, 1.433), while that in AML group was 0.522 1(0.242 2, 0.723 7). The expression level of SPOP in AML group was significantly lower than that in normal control group ( P < 0.001). After the overexpression of SPOP, the proportion of apoptotic cells in the U937 overexpression group and THP-1 overexpression group was 10.9%±0.3% and 4.6%±015%, which were higher than 8.9%±0.3% and 3.0%±0.30% in the Empty Vector group, respectively (both P < 0.05). The expression of Caspase3 in U937 overexpression group and THP-1 overexpression group was 1.154±0.086 and 1.2±0.077, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). The ratio of Bax/Bcl-2 in U937 overexpression group and THP-1 overexpression group was 1.328±0.057 and 1.669±0.15, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). In the cell proliferation experiment, the number of cells in the U937 overexpression group and THP-1 overexpression group were both slightly lower than those in the Empty Vector group, but the differences were not statistically significant (P >0.05). In the cell cycle experiment, the proportion of G₁ cells in the U937 overexpression group and THP-1 overexpression group were both slightly higher than those in the Empty Vector group, but the differences were not statistically significant (P >0.05). CONCLUSION SPOP can promote the apoptosis of leukemic cells, and its mechanism may be related to down-regulation of Bcl-2 expression and up-regulation of Bax and Caspase3 expression.
Humans ; Leukemia, Myeloid, Acute/pathology* ; Apoptosis ; Repressor Proteins/genetics* ; Cell Proliferation ; Nuclear Proteins/genetics* ; Cell Cycle ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Caspase 3/metabolism* ; bcl-2-Associated X Protein/metabolism* ; U937 Cells ; Cell Line, Tumor ; RNA, Messenger/genetics*

OBJECTIVES: To explore the mechanism by which histone deacetylase 1 (HDAC1) regulates steroid-induced apoptosis of mouse osteocyte-like MLO-Y4 cells. METHODS: MLY-O4 cells were treated with 400 nmol/L trichostatin A (TSA) or 1 mmol/L dexamethasone for 24 h or transfected with a HDAC1-overexpressing vector prior to TSA or dexamethasone treatment. The changes in the expressions of HDAC1, SP1, cleaved caspase-3 and Bax, SP1 acetylation level, cell proliferation, and cell apoptosis were examined. The interaction between HDAC1 and SP1 was determined with immunoprecipitation assay and Western blotting. RESULTS: Treatment with dexamethasone significantly increased cell apoptosis, enhanced the expressions of cleaved caspase-3 and Bax, reduced HDAC1 expression, and suppressed proliferation of MLO-Y4 cells. Both TSA and dexamethasone obviously increased SP1 acetylation level and the expression of SP1 in MLO-Y4 cells. HDAC1 overexpression in the cells significantly attenuated the effect of TSA and dexamethasone, promoted cell proliferation, lowered the expressions of SP1, cleaved caspase-3 and Bax, and inhibited dexamethasone-induced cell apoptosis. Immunoprecipitation assay and Western blotting demonstrated the interaction between HDAC1 and SP1 in the cells. CONCLUSIONS HDAC1 inhibits dexamethasone-induced apoptosis and promotes proliferation of cultured mouse osteocytes by suppressing SP1 expression via promoting its deacetylation.
Animals ; Apoptosis/drug effects* ; Mice ; Histone Deacetylase 1/genetics* ; Osteocytes/drug effects* ; Sp1 Transcription Factor/metabolism* ; Acetylation ; Dexamethasone/pharmacology* ; Cell Proliferation/drug effects* ; Caspase 3/metabolism* ; Cell Line ; Hydroxamic Acids/pharmacology* ; bcl-2-Associated X Protein/metabolism*

OBJECTIVES: To investigate the structural changes of rat thoracic aorta and changes in expression levels of Bmal1 and cyclins in thoracic aorta endothelial cells following heat stress. METHODS: Twenty male SD rats were randomized equally into control group and heat stress group. After exposure to 32 ℃ for 2 weeks in the latter group, the rats were examined for histopathological changes and Bmal1 expression in the thoracic aorta using HE staining and immunohistochemistry. In the cell experiments, cultured rat thoracic aortic endothelial cells (RTAECs) were incubated at 40 ℃ for 12 h with or without prior transfection with a Bmal1-specific small interfering RNA (si-Bmal1) or a negative sequence. In both rat thoracic aorta and RTAECs, the expressions of Bmal1, the cell cycle proteins CDK1, CDK4, CDK6, and cyclin B1, and apoptosis-related proteins Bax and Bcl-2 were detected using Western blotting. TUNEL staining was used to detect cell apoptosis in rat thoracic aorta, and the changes in cell cycle distribution and apoptosis in RTAECs were analyzed with flow cytometry. RESULTS: Compared with the control rats, the rats exposed to heat stress showed significantly increased blood pressures and lowered heart rate with elastic fiber disruption and increased expressions of Bmal1, cyclin B1 and CDK1 in the thoracic aorta (P<0.05). In cultured RTAECs, heat stress caused significant increase of Bmal1, cyclin B1 and CDK1 protein expression levels, which were obviously lowered in cells with prior si-Bmal1 transfection. Bmal1 knockdown also inhibited heat stress-induced increase of apoptosis in RTAECs as evidenced by decreased expression of Bax and increased expression of Bcl-2. CONCLUSIONS Heat stress upregulates Bmal1 expression and causes alterations in expressions of cyclins to trigger apoptosis of rat thoracic aorta endothelial cells, which can be partly alleviated by suppressing Bmal1 expression.
Animals ; ARNTL Transcription Factors/genetics* ; Male ; Aorta, Thoracic/metabolism* ; Rats ; Rats, Sprague-Dawley ; Endothelial Cells/metabolism* ; Apoptosis ; Cells, Cultured ; Heat-Shock Response ; Cyclin B1/metabolism* ; CDC2 Protein Kinase/metabolism* ; Cyclins/metabolism* ; RNA, Small Interfering ; bcl-2-Associated X Protein/metabolism*

The Chinese hamster ovary (CHO) cell is the most representative mammalian cell protein expression system, and it is widely used in recombinant protein, vaccine and other biopharmaceutical fields. However, due to its vulnerability to environmental factors, apoptosis, and metabolic inhibitors, CHO cells demonstrate poor robustness, and thus the integrated viable cell density and unit cell productivity are largely limited. To improve the robustness and foreign protein expression efficiency of CHO cells, we employed CRISPR/Cas9 to knock out the apoptosis genes Bax and Bak and the lactate dehydrogenase gene LDHa, thereby blocking apoptosis and lactic acid metabolism pathways. The results of apoptosis and single cell viability detection showed that the number of apoptotic cells in the knockout cell lines Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- was reduced by 22.51%, 37.73%, and 64.12%, respectively, compared with the wild-type cell line CHO-K1, which indicated that the anti-apoptotic ability was significantly improved. After staurosporine treatment, the single cell viability of Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- cells was increased by 30.8%, 22%, and 41.1%, respectively. After treatment with puromycin, the single cell viability of Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- cells was increased by 26.7%, 30.7%, and 38.8%, respectively. To further investigate the production performance of cells obtained after blocking apoptosis and lactic acid metabolism pathways, we induced transient expression of human tissue plasminogen activator (tPA) in these cells. The results showed that the secretion of tPA in Bax^-/-, Bax-Bak^-/-, and LDHa-Bax-Bak^-/- cells was 11.12%, 46.18%, and 63.13%, respectively, higher than that in wild-type CHO-K1 cells. The expression of intracellular tPA was increased by 35.65%, 130%, and 192.15%. In conclusion, blocking apoptosis and lactic acid metabolism pathways simultaneously can improve cell robustness and productivity, with the performance better than blocking the apoptosis pathway alone. The above results indicated that the constructed cell lines were expected to be the delivery carriers of protein drugs such as medicinal peptides, and better used for the treatment of diseases.
CHO Cells ; Cricetulus ; Animals ; Apoptosis/genetics* ; Lactic Acid/metabolism* ; Recombinant Proteins/biosynthesis* ; L-Lactate Dehydrogenase/genetics* ; bcl-2-Associated X Protein/genetics* ; bcl-2 Homologous Antagonist-Killer Protein/genetics* ; Cricetinae ; CRISPR-Cas Systems ; Staurosporine/pharmacology*

This paper aimed to investigate the effect of total flavonoids of buckwheat flower and leaf on myocardial cell apoptosis and Wnt/β-catenin/peroxisome proliferator-activated receptor γ(PPARγ) pathway in arrhythmic rats. SD rats were randomly divided into a control group, a model group, a low-dose(20 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a medium-dose(40 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a high-dose(80 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a propranolol hydrochloride(2 mg·kg~(-1)) group, with 12 rats in each group. Except the control group, rats in other groups were prepared as models of arrhythmia by sublingual injection of 1 mL·kg~(-1) of 0.002% aconitine. After grouping and intervention with drugs, the arrhythmia, myocardial cells apoptosis, myocardial tissue glutathione peroxidase(GSH-Px), catalase(CAT), malondialdehyde(MDA), serum interleukin-6(IL-6), prostaglandin E2(PGE2) levels, myocardial tissue apoptosis, and Wnt/β-catenin/PPARγ pathway-related protein expression of rats in each group were measured. As compared with the control group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA levels in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels increased significantly in the model group, whereas the GSH-Px and CAT levels, and Bcl-2 and PPARγ protein expression levels in myocardial tissues reduced significantly. As compared with the model group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA leve in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels reduced in the drug intervention groups, whereas the GSH-Px and CAT levels and Bcl-2 and PPARγ protein expression levels in myocardial tissues increased. The groups of total flavonoids of buckwheat flower and leaf were in a dose-dependent manner. There was no significant difference in the levels of each index in rats between the propranolol hydrochloride group and the high-dose group of total flavonoids of buckwheat flower and leaf. The total flavonoids of buckwheat flower and leaf inhibit the activation of Wnt/β-catenin pathway, up-regulate the expression of PPARγ, reduce oxidative stress and inflammatory damage in myocardial tissues of arrhythmic rats, reduce myocardial cell apoptosis, and improve the symptoms of arrhythmia in rats.
Rats ; Animals ; PPAR gamma/metabolism* ; Fagopyrum/genetics* ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; beta Catenin/metabolism* ; Interleukin-6 ; Flavonoids/pharmacology* ; Propranolol/pharmacology* ; Ventricular Fibrillation ; Dinoprostone ; Wnt Signaling Pathway ; Plant Leaves/metabolism* ; Flowers/metabolism* ; Apoptosis ; Cardiac Complexes, Premature

OBJECTIVES: Hyperhomocysteinaemia (Hcy) is an independent risk factor for cardiovascular and cerebrovascular diseases. MicroRNA (miR)-18a-5p is closely related to cardiovascular diseases. This study aims to investigate the effects of miR-18a-5p on homocysteine (Hcy)-induced myocardial cells injury. METHODS: H9c2 cells were transfected with miR-18a-5p mimic/miR-18a-5p mimic negative control (NC) or combined with Hcy for intervention, and untreated cells were set as a control group. The transfection efficiency was verified by real-time RT-PCR, and cell counting kit-8 (CCK-8) assay was used to determine cell viability. Flow cytometry was used to detect apoptosis and reactive oxygen species (ROS) levels. Western blotting was performed to measure the protein levels of microtubule-associated protein 1 light chain 3 (LC3)-I, LC3-II, Beclin1, p62, Bax, Bcl-2, and Notch2. Dual luciferase reporter assay was used to detect the interaction of miR-18a-5p with Notch2. RESULTS: Compared with the control, treatment with Hcy or transfection with miR-18a-5p mimic alone, or combined treatment with Hcy and miR-18a-5p mimic/miR-18a-5p mimic NC significantly reduced the H9c2 cell viability, promoted apoptosis and ROS production, up-regulated the expressions of Bax and Beclin, down-regulated the expressions of Bcl-2, p62, and Notch2, and increased the ratio of LC3-II/LC3-I (all P<0.05). Compared with the combined intervention of miR-18a-5p mimic NC and Hcy group, the above indexes were more significantly changed in the combined intervention of miR-18a-5p mimic and Hcy group, and the difference between the 2 groups was statistically significant (all P<0.05). There is a targeted binding between Notch2 and miR-18a-5p. CONCLUSIONS MiR-18a-5p could induce autophagy and apoptosis via increasing ROS production in cardiomyocytes, and aggravate Hcy-induced myocardial injury. Notch2 is a target of miR-18a-5p.
Apoptosis/genetics* ; Autophagy/genetics* ; bcl-2-Associated X Protein ; MicroRNAs/metabolism* ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Reactive Oxygen Species ; Rats ; Animals ; Myocytes, Cardiac/drug effects* ; Homocysteine/adverse effects* ; Hyperhomocysteinemia

Objective To investigate the impacts of forkhead box M1(FOXM1)on the proliferation,invasion,and drug resistance of gastric cancer cells by regulating the circular RNA circ_NOTCH1.Methods Western blotting and real-time quantitative PCR were performed to determine the expression of FOXM1 protein and circ_NOTCH1,respectively,in the gastric cancer tissue,para-carcinoma tissue,human normal gastric mucosa epithelial cell line GES-1 and gastric cancer cell lines MGC-803,HGC-27,and BGC-823.BGC-823 cells were classified into the following groups:control,short hairpin RNA FOXM1(sh-FOXM1)and negative control(sh-NC),small interfering RNA circ_NOTCH1(si-circ_NOTCH1)and negative control(si-NC),and sh-FOXM1+circ_NOTCH1 overexpression plasmid(sh-FOXM1+pcDNA-circ_NOTCH1)and sh-FOXM1+negative control(sh-FOXM1+pcDNA).CCK-8 assay and clone formation assay were employed to measure the cell proliferation,and Transwell assay to measure cell invasion.After treatment with 1.0 mg/L adriamycin for 48 h,the cell resistance in each group was analyzed.Western blotting was employed to determine the expression levels of FOXM1,proliferating cell nuclear antigen(PCNA),Bax,multi-drug resistance-associated protein 1(MRP1),and multi-drug resistance gene 1(MDR1).RNA pull-down and RNA immunoprecipitation were employed to examine the binding of circ_NOTCH1 to FOXM1 protein.Results Compared with those in the para-carcinoma tissue,the expression levels of FOXM1 protein and circ_NOTCH1 in the gastric cancer tissue were up-regulated(all P<0.001).Compared with GES-1 cells,MGC-803,HGC-27,and BGC-823 cells showed up-regulated expression levels of FOXM1 protein and circ_NOTCH1(all P<0.001).Compared with the control group and sh-NC group,the sh-FOXM1 group with down-regulated expression of FOXM1 protein and circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with the control group and the si-NC group,the si-circ_NOTCH1 group with down-regulated expression of circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with sh-FOXM1 group and sh-FOXM1+pcDNA group,the sh-FOXM1+pcDNA-circ_NOTCH1 group with up-regulated expression of circ_NOTCH1 showed increased optical density value,clone formation rate,cell invasion number,and cell viability,up-regulated expression of PCNA,MRP1,and MDR1,and down-regulated expression of Bax protein(all P<0.001).FOXM1 protein was able to interact with circ_NOTCH1.Conclusion Interference with FOXM1 may inhibit the proliferation,invasion,and drug resistance of gastric cancer cells by silencing circ_NOTCH1 expression.
Humans ; bcl-2-Associated X Protein/metabolism* ; Carcinoma ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Drug Resistance ; Forkhead Box Protein M1/metabolism* ; Gene Expression Regulation, Neoplastic ; MicroRNAs/genetics* ; Proliferating Cell Nuclear Antigen/metabolism* ; Receptor, Notch1/metabolism* ; RNA, Small Interfering/genetics* ; Stomach Neoplasms/genetics*