Effect of ixazomib on apoptosis and NF-κB signaling pathway in pancreatic cancer cells

AIM:To investigate the effects of ixazomib on the apoptosis and NF-κB signaling pathway in pancreatic cancer cells. METHODS:Human pancreatic cancer cell lines CFPAC-1 and PANC-1 were cultured, and the cells were treated with ixazomib at 0, 10, 20, 30 and 40 nmol/L for 12, 18, 24 and 48 h. The expression of NF-κB p65, IκB kinase (IKK), Bax and caspase-3 in the cells at mRNA and protein levels was determined by RT-qPCR and Western blot. The cell viability was measured by CCK-8 assay. The apoptosis was analyzed by flow cytometry. RESULTS:Treatment with ixazomib at 10~40 nmol/L inhibited the viability of PANC-1 cells and CFPAC-1 cells, and the inhibitory rate was increased significantly with the increases in the concentration and time (P<0.05). Compared with the control cells, treatment with ixazomib significantly increased the apoptotic rates of PANC-1 cells and CFPAC-1 cells in a dose- dependent manner (P<0.05), and significantly decreased the mRNA expression levels of NF-κB p65 and IKK in the PANC-1 cells and CFPAC-1 cells (P<0.05), while the mRNA expression levels of apoptotic factors Bax and caspase-3 in the PANC-1 cells and CFPAC-1 cells were significantly increased (P<0.05). The results of Western blot showed that treatment with ixazomib significantly decreased the protein levels of NF-κB p65 and IKK in the PANC-1 cells and CFPAC-1 cells (P<0.05), which was consistent with the results of mRNA expression. The protein levels of apoptosis factors Bax and caspase-3 in the CFPAC-1 cells were significantly increased (P<0.05), and the protein level of caspase-3 in the PANC-1 cells was increased significantly (P<0.05). However, Bax protein did not increase significantly in 10 nmol/L ixazomib group. CONCLUSION:Ixazomib, a proteasome inhibitor, inhibits the viability of pancreatic cancer cells and promotes apoptosis by inhibiting the activation of NF-κB signaling pathway in a time- and dose-dependent manner.     

Inhibitory effect of butylphthalide on apoptosis of hippocampal neurons in Alzheimer disease rats via SIRT1/NF-κB signaling pathway

AIM: To investigate the effect of butylphthalide on apoptosis of hippocampal neurons in Alzheimer disease (AD) rats via SIRT1/NF-κB signaling pathway and its mechanism. METHODS: AD rat model was established by intragastric administration of AlCl₃ and intraperitoneal injection of D-galactose. After treated with butylphthalide at 25 mg/kg (low dose), 50 mg/kg (medium dose) and 100 mg/kg (high dose), the effects of butylphthalide on the morphology of hippocampal neurons, apoptosis rate, and the protein levels of Bcl-2, Bax, cleaved caspase-3 and the SIRT1/NF-κB signaling pathway associated proteins were determined by HE staining, flow cytometry and Western blot, respectively. After treated with SIRT1 agonist SRT1720 and inhibitor sirtinol, the role of SIRT1/NF-κB signaling pathway in hippocampal neuronal apoptosis was observed. On the basis of giving 50 mg/kg butylphthalide, sirtinol was administered, and the effect of butylphthalide on neuronal apoptosis regulated by SIRT1/NF-κB signaling pathway was evaluated. RESULTS: The morphology of hippocampal neurons in the AD rats were improved, the apoptosis rate of hippocampal neurons and the protein levels of Bax and cleaved caspase-3 were inhibited, and the protein levels of Bcl-2 and the activation of SIRT1/NF-κB signaling pathway were promoted by butylphthalide significantly (P<0.05). The protein expression of Bcl-2 and the activation of SIRT1/NF-κB signaling pathway were promoted, and the apoptosis of hippocampal neurons and the protein levels of Bax and cleaved caspase-3 were inhibited by SRT1720 remarkably (P<0.05), whereas the effect of sirtinol was contrary to that of SRT1720. After sirtinol treatment, the inhibitory effect of butylphthalide on apoptosis of hippocampal neurons, the protein levels of Bax and cleaved caspase-3, and the promotion of Bcl-2 protein expression in hippocampal neurons were markedly weakened (P<0.05). CONCLUSION: Butylphthalide inhibits the apoptosis of hippocampal neurons in the AD rats by down-regulating the protein expression of Bax and cleaved caspase-3, and up-regulating the protein expression of Bcl-2 through activating SIRT1/NF-κB signaling pathway.     

Resveratrol attenuates inflammatory pain induced by complete Freund's adjuvant via NF-κB signaling pathway in a mouse model

AIM: To investigate the anti-inflammatory action of resveratrol (Res) and its correlation with nuclear factor-κB (NF-κB) signaling pathway in a mouse model of inflammatory pain.METHODS: BALB/c mice (n=60) were randomly divided into 6 groups:normal control group, inflammatory pain model group, positive control (dexamethasone, 0.5 mg/kg) group and resveratrol (100, 50 and 25 mg/kg) groups (10 mice in each group). In order to observe the anti-inflammatory pain effects of reseratrol on mice, the paw withdrawal mechanical threshold, paw withdrawal thermal latency and cold withdrawal times were detected. In order to analyze the mechanism of analgesic effect of resveratrol, the expression levels of NF-κB, inhibitor of NF-κB (IκB) α, inhibitor of NF-κB kinase (IKK) β, tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the spinal cord tissues (L4~L6) of the mice were determined by RT-PCR and Western blot.RESULTS: The resveratrol at 100 and 50 mg/kg increased the paw withdrawal mechanical threshold, prolonged the paw withdrawal thermal latency, and decreased the cold withdrawal times in the inflammatory pain mice (P<0.05 or P<0.01). The resveratrol at 100 mg/kg down-regulated the mRNA and protein expression levels of NF-κB, IκBα, IKKβ, TNF-α and IL-1β in the spinal cord tissues (L4~L6) of inflammatory pain mice (P<0.05 or P<0.01).CONCLUSION: Resveratrol ameliorates the inflammatory pain of the mice induced by complete Freund's adjuvant. The mechanism is related to the inhibition of NF-κB signaling pathway.     

Emodin reduces hypoglycemia/hypoxia-induced injury of microglia by TLR4/NF-κB signaling pathway

AIM: To investigate the mechanism of emodin on the protection of glucose-deficient/anoxic microglia. METHODS: A microglia BV2 cell model induced by hypoglycemia/hypoxia (HH) was established. The glucose-deficient/anoxic cells treated with emodin were labeled as HH+emodin (20, 40 and 80 μmol/L) groups. The BV2 cells with TLR4 over-expression treated with emodin under hypoglycemia/hypoxia condition was labeled as HH+pcDNA-TLR4+ emodin (40 μmol/L) group. The cell viability was measured by MTT assay. Lactate dehydrogenase (LDH) and tumor necrosis factor-α (TNF-α) levels were detected by ELISA. The apoptosis was analyzed by flow cytometry. The protein levels of Bax, Bcl-2, TLR4, p-IκB and IκB were determined by Western blot. RESULTS: Compared with HH+DMSO group, the viability was significantly increased, the levels of LDH and TNF-α and apoptotic rate were significantly decreased, the protein levels of Bax, TLR4 and p-IκB were significantly decreased, the protein level of Bcl-2 was significantly increased in HH+emodin groups (P<0.05). Over-expression of TLR4 reversed the effect of emodin on promoting the viability and inhibiting apoptosis in the BV2 cells. CONCLUSION: Emodin has a protective effect on hypoglycemia/hypoxia induced microglia, and its mechanism may be related to the inactivation of TLR4/NF-κB signaling pathway.     

Asiaticoside attenuates hypoxic pulmonary hypertension in mice by inhibiting NF-κB/p38 signaling pathway

AIM: To investigate whether asiaticoside attenuates hypoxic pulmonary hypertension by inhibiting p38/NF-κB signaling pathway. METHODS: BALB/c mice (n=30) were randomly divided into normoxia (N) group, hypoxia (H) group, and hypoxia+asiaticoside group. Right ventricular systolic pressure (RVSP), mean carotid artery pressure (mCAP), the weight ratio of right ventricle/(left ventricle+ventricular septum)[RV/(LV+S)], the ratio of right ventricle/body weight (RV/BW), vessel wall area/vessel total area (WA/TA) and vessel wall diameter/vessel wall total diameter (WT/TT) were determined after the model was established. The protein levels of p38, p-p38, NF-κB and p-NF-κB in the lung tissues were detected by Western blot. The fluorescence intensity of p-p38 and p-NF-κB were measured by immunofluorescence method. The serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured by ELISA. RESULTS: Compared with N group, the levels of RVSP, RV/(LV+S), RV/BW, WA/TA and WT/TT were significantly increased in H group, while administration of asiaticoside decreased the levels of RVSP, RV/(LV+S), RV/BW, WA/TA and WT/TT (P<0.05). Compared with N group, the relative protein levels of p-p38 and p-NF-κB in H group were significantly increased (P<0.05), and the concentrations of IL-6 and TNF-α were significantly increased, which were apparently attenuated by asiaticoside injection. CONCLUSION: Inhibition of p38/NF-κB signaling pathway and reduction of inflammatory responses may be the important mechanisms of asiaticoside in the prevention and treatment of hypoxic pulmonary hypertension.     

Trx-1 over-expression attenuates oxidative stress injury in MPP+ -induced PC12 cells by regulating NF-κB signaling pathway

AIM:To investigate the inhibitory effect of thioredoxin 1 (Trx-1) over-expression on oxidative stress injury in 1-methyl-4-phenylpyridinium (MPP⁺)-induced rat pheochromocytoma PC12 cells by regulating NF-κB signaling pathway.METHODS:The PC12 cells were damaged by treatment with MPP⁺ at 1, 3 and 5 mmol/L, and the optimal concentration of 3 mmol/L was selected. The cell viability was measured by MTT assay. The oxidative stress indexes lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in the cell culture supernatant were detected, and the protein expression of Trx-1 was determined by Western blot. Lentiviral infection with Ad-Trx-1-GFP sequence was used to establish a model of MPP⁺-treated PC12 cells with Trx-1 over-expression. The effects of Trx-1 over-expression on the cell viability, oxidative stress responses and NF-κB signaling pathway were determined by MTT assay, commercial kits and Western blot. The effects of phorbol 12-myristate 13-acetate (PMA), an activator of NF-κB signaling pathway, on the viability and oxidative stress of PC12 cells were observed. The NF-κB signaling pathway inhibitor pyrrolidine dithiocarbamate (PDTC) was used in MPP⁺-treated PC12 cells with Trx-1 over-expression, and the cell viability and oxidative stress responses were measured. RESULTS:The viability of PC12 cells, SOD activity in the supernatant and protein expression of Trx-1 were decreased, while LDH activity and MDA content in the supernatant were increased significantly by treatment with MPP⁺ at 1, 3 and 5 mmol/L. The effect of MPP⁺ at 3 mmol/L and 5 mmol/L was significantly greater than that at 1 mmol/L (P<0.05), and no significant difference between 3 mmol/L and 5 mmol/L was observed (P>0.05). The inhibitory effect of MPP⁺ on the viability of PC12 cells, and the oxidative stress injury and activation of NF-κB signaling pathway induced by MPP⁺ were significantly attenuated by over-expression of Trx-1. The inhibitory effect of MPP⁺ on the viability of PC12 cells and the oxidative stress injury induced by MPP⁺ were promoted by the activation of NF-κB signaling pathway, while the protective effects of Trx-1 over-expression on the MPP⁺-treated PC12 cells were enhanced by the inhibition of NF-κB signaling pathway. CONCLUSION:Over-expression of Trx-1 protects MPP⁺-treated PC12 cells from oxidative stress injury by regulating NF-κB signaling pathway.     

Down-regulated BARF1 expression induces EBV-positive gastric carcinoma cell apoptosis via activating caspase-dependent mitochondrial pathway

AIM: To investigate the effects of BARF1 down-regulation on EBV-positive gastric carcinoma cell apoptosis, and the molecular mechanisms by BARF1 silencing-mediated apoptosis. METHODS: After NUGC3 and SNU719 cells were transfected with NCsiRNA and siRNA, respectively, the protein levels of BARF1, Bcl-2, Bax, cytochrome C, caspase 3 and capase 9 were detected by Western blot, and the mRNA expression of BARF1, Bcl-2 and Bax was determined by RT-PCR. The cell viability was measured by the method of Trypan blue exclusion and the cell apoptosis was analyzed by flow cytometry analysis with Annexin V-FITC/PI staining. The expression of the apoptosis-related proteins in the cells transfected with siRNA and NCsiRNA was examined by human apoptosis antibody arrays. Mitochondrial membrane potential was determined by flow cytometry. The interaction between Apaf-1 and caspase 9 was confirmed by immunoprecipitation. RESULTS: Compared with untreated and NCsiRNA groups, BARF1 gene silencing significantly inhibited the cell viability, induced apoptosis, and reduced the mitochondrial membrane potential in the NUGC3 and SNU719 cells transfected with siRNA. BARF1 gene silencing up-regulated the expression of pro-apoptotic proteins and down-regulated the expression of anti-apoptotic proteins, and the Bcl-2/Bax ratio was significantly decreased. In BARF1 gene silencing cells, the caspase inhibitor z-VAD-fmk inhibited BARF1 silencing-mediated apoptosis, and significantly increased the levels of cleaved caspase 3 and caspase 9. The concentration of cytochrome C significantly increased as compared with NCsiRNA group, and Apaf-1 interacted with caspase 9 in the cytoplasm. CONCLUSION: BARF1 silencing induces apoptosis via the mitochondrial pathway through regulating the expression of Bcl-2 and Bax proteins in a caspase-dependent manner in the NUGC3 and SNU719 cells.     

Crosstalk between Wnt/β-catenin and NF-κB signaling #br# pathways during wound healing

Both Wnt/β-catenin and NF-κB signaling pathways are conserved pathways that regulate a variety of biological processes throughout the development and adult lifetime of mammals. Recent findings suggest that the 2 signaling pathways can cross-regulate each other. Several studies show that there are both positive and negative regulations between the 2 pathways. Some major components are involved in the cross-regulation of the 2 pathways such as Wnt proteins, DKK1, E-cadherin, GSK-3β, IKKs/IκB and so on. By reviewing the literature, we conjecture that the crosstalk between the 2 pathways regulate the wound healing process by intervening in the inflammation, fibroblast and angiogenesis, but the concrete mechanism is still unknown.     

Linarin inhibits migration and invasion abilities of human breast cancer MDA-MB-231 cells through IKK/NF-κB signaling pathway

AIM: To investigate the effect of linarin (LIN) on the migration and invasion abilities of human breast cancer MDA-MB-231 cells and its underlying mechanism. METHODS: MCF-7, MDA-MB-231 and MCF-10A cells were cultured in vitro and treated with LIN at 5, 10, 20, 40, 80 and 160 μmol/L for 24 h, and the cell proliferation was measured by CCK-8 assay and colony formation assay. The protein levels of Snail, E-cadherin, matrix metalloproteinase-9 (MMP-9), IκBα, p-IKKα/β and p-p65 were determined by Western blot. RESULTS: LIN remarkably reduced the viability of MDA-MB-231 cells in a dose-dependent manner (P<0.05), and the IC₅₀ was 55.89 μmol/L for 24 h. LIN decreased the colony formation rate of MDA-MB-231 cells at the concentration of 20 μmol/L (P<0.05). After exposed to LIN at 5 μmol/L and 10 μmol/L for 24 h, the migration and invasion abilities of the MDA-MB-231 cells were significantly reduced (P<0.05), the protein expression levels of E-cadherin and IκBα were up-regulated (P<0.05), the protein expression levels of Snail and MMP-9 were down-regulated (P<0.05), and the phosphorylation levels of IKKα/β and p65 were decreased (P<0.05) in comparison with the control group. Meanwhile, IKK-16 (IKKα/β inhibitor) and PDTC (NF-κB inhibitor) also down-regulated the protein expression levels of Snail and MMP-9 (P<0.05), and up-regulated the protein expression level of E-cadherin (P<0.05). CONCLUSION: LIN down-regulates the protein expression levels of Snail and MMP-9, and up-regulates the protein expression level of E-cadherin most likely through inhibiting IKK/NF-κB signaling pathway, and ultimately lead to decreases in the migration and invasion abilities of MDA-MB-231 cells.     

Ethanol extract from Cortex Albiziae attenuates mouse acute liver injury induced by carbon tetrachloride via modulation of NF-κB pathway

AIM:To investigate the protective effect of ethanol extract from Cortex Albiziae on acute liver injury, and to explore its possible mechanism. METHODS:Acute liver injury in mice was induced by single intraperitoneal injection of 25% carbon tetrachloride (olive oil solubilization). The effective parts of ethanol extract from Cortex Albizziae against acute liver injury were screened. The pathological changes of the liver tissues were examined by pathological sections with HE staining. The activity of total superoxide dismutase (T-SOD) and the content of malondialdehyde (MDA) of the liver tissues were detected, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were mea-sured by ELISA, and the protein expression levels of NF-κB p65, Bcl-2 and Bax in the liver cells of the mice in each group were determined by Western blot. RESULTS:Compared with model group, the serum levels of AST and ALT in low-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-L, 4 mg·kg^-1·d^-1) group and high-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-H, 8 mg·kg^-1·d^-1) group were significantly decreased. The necrosis extent and degree of the hepatocytes and infiltration of inflammatory cells were significantly lower than that in model group. Compared with model group, the serum levels of TNF-α and IL-6 in AB-H group and AB-L group were significantly decreased (P<0.05). The protein level of NF-κB p65 in the nuclei of mouse liver cells in AB-H group and AB-L group were also decreased significantly (P<0.05). Compared with model group, the protein expression of Bax was decreased, the protein expression of Bcl-2 was increased, and the Bcl-2/Bax ratio was increased in AB-L group and AB-H group. CONCLUSION:The n-butanol phase of ethanol extract from Cortex Albiziae may protect the liver by reducing the activation of NF-κB p65, inhibiting the excessive release of inflammatory cytokines IL-6 and TNF-α, and decreasing hepatocyte apoptosis via regulating Bcl-2 and Bax expression.     

Role of NF-κB in inducing HEL cell proliferation and apoptosis during human cytomegalovirus infection

AIM:To investigate whether human cytomegalovirus(HCMV) regulate human embryonic lung fibroblast(HEL) cell proliferation and apoptosis by activating NF-κB.METHODS:Immunohistochemistry and Western blot analysis were used to detect the NF-κB translocation and/or Bcl-2 and the levels of I-κBα during HCMV infection. Apoptotic cell were examined by flow cytometry, and the HEL cell proliferation was determined by MTT.RESULTS:The levels of NF-κB in the nucleus reached highly 48 h postinfection, and the levels of I-κBα were low 24 h postinfection. The activity of NF-κB was inhibited 120 h postinfection. The levels ofbcl-2was accorded with the activity of NF-κB. HCMV promoted HEL cells to proliferate before 72 h postinfection and induced apoptosis 120 h postinfection.CONCLUSION:NF-κB plays a role in HEL cell proliferation and apoptosis during HCMV infection, and it involves in the pathological mechanisms of diseases associated with HCMV infection.     

Quercitrin promotes apoptosis of gastric cancer cell line SGC7901 by inhibiting PI3K/AKT signaling pathway

AIM: To investigate whether quercitrin induces apoptosis of gastric cancer cell line SGC7901 by inhibition of PI3K/AKT signaling pathway. METHODS: The human gastric cancer SGC7901 cells were selected as the research object. The cytotoxicity of quercitrin was detected by MTT assay, and IC₅₀ value of quercitrin was calculated. The SGC7901 cells were divided into control group, quercitrin group (incubated with 200 μmol/L quercitrin), insulin-like growth factor-1 (IGF-1) group (incubated with 100 μg/L IGF-1) and quercitrin+IGF-1 group (incubated with 200 μmol/L quercitrin and 100 μg/L IGF-1). After 48 h, the apoptosis of SGC7901 cells was analyzed by flow cytometry, and the protein levels of cleaved caspase-3, p-AKT (Ser473), AKT, p-PI3K (Tyr508) and PI3K were determined by Western blot. RESULTS: The viability of SGC7901 cells was significantly decreased as the concentration of quercitrin increased, starting at 100 μmol/L (P<0.05). The IC₅₀ value of quercitrin for 48 h was 275.40 μmol/L. After treatment with 200 μmol/L quercitrin for 48 h, the apoptosis rate and the protein level of cleaved caspase-3 in quercitrin group were significantly increased (P<0.05), and the phosphorylated levels of AKT and PI3K were significantly decreased compared with control group (P<0.05). Treatment with quercitrin and IGF-1 inhibited the effect of quercitrin on SGC7901 cells compared with quercitrin group. CONCLUSION: Quercitrin may induce apoptosis of gastric cancer cell line SGC7901 by inhibiting the activation of PI3K/AKT signaling pathway.     

Effect of NF-κB inhibitor pyrrolidine dithiocarbamate on proliferation and apoptosis of human multiple myeloma U266 cells

AIM:To explore the effect of pyrrolidine dithiocarbamate (PDTC),an NF-κB inhibitor,on the proliferation and apoptosis of human multiple myeloma U266 cells and its mechanisms.METHODS:The U266 cells were treated with PDTC at different concentrations (0,25,50,100 and 200 μmol/L)in vitro.The growth inhibitory rate of the U266 cells was detected by CCK-8 assay and cell counting.The cell cycle of the U266 cells was determined by flow cyto-metry,and the apoptosis was examined by flow cytometry with Annexin V-FITC/PI staining.The effect of PDTC on the expression of DNA methyltransferase 1(DNMT1) at mRNA and protein levels was measured by RT-qPCR and Western blot,respectively.The effects of PDTC on the protein levels of NF-κB (P65),DNMT1,Bcl-2,cyclin D1,cleaved caspase-3 and cleaved caspase-8 were determined by Western blot.RESULTS:The protein level of NF-κB (P65) was decreased after treatment with PDTC for 48 h or 72 h.PDTC inhibited the proliferation of U266 cells in both dose-and time-dependent manners.After treatment with PDTC for 48 h,the percentage of U266 cells in G₂ phase increased compared with control group (P<0.05).PDTC induced the apoptosis of U266 cells in a dose-dependent manner.The expression of DNMT1 at mRNA and protein levels decreased (P<0.05).The results of Western blot showed that the expression of Bcl-2 in PDTC groups decreased,while the protein levels of cyclin D1,cleaved caspase-3 and cleaved caspase-8 were higher than those in control group (P<0.05).CONCLUSION:The NF-κB inhibitor PDTC inhibits the proliferation of U266 cells by inducing cell apoptosis.It may be related to the down-regulated expression of DNMT1,cell cycle arrest and activation of the apoptotic pathways.     

Signal transduction pathway and blocking strategies of NF-κB

NF-κB is thought of as a genetic switch to control expressions of many target genes and directly participates in pathogenesis of infection, inflammation, stress, immunoresponse, cellular apoptosis, toxic shock and tumor as well as cell-cycle regulation and cell differentiation.The overactivation of NF-κB is intimately involved in many human diseases.Various therapeutic strategies against NF-κB, to date, in-clude anti-inflammatory drugs, antioxidants, immunosuppressive agents, inhibitors of protease and protea-some, prostaglandings, nitric oxide, IL-10, microbial products, synthetic inhibitors, antisense oligon cleotides and decoy deoxyoligonucleotides.Studies are underway to develop NF-κB member-specific and cell type-specific drugs that can inhibit the activation of NF-κB only in target cells and that may become a novel way to treat the human diseases.     

Effects of Jiedu-Qingfei mixture on NF-κB and p38 MAPK pathways in lung tissues of rats with Mycoplasma pneumoniae infection

AIM: To observe the therapeutic effect of Jiedu-Qingfei mixture on Mycoplasma pneumoniae (MP)-infected rat lung tissues and to explore its mechanism. METHODS: SD rats (n=40) were randomly divided into 4 groups:blank control group, model group, Jiedu-Qingfei group and positive control group, with 10 rats in each group. The rats in experimental groups were slowly dripped with 1×10⁹ CFU/L MP solution into their nostrils for 4 d. One rat in each group was sacrificed for MP nucleic acid detection at the second day after inoculation, and the other rats were given gavage therapy. The rats in blank control group and model group were intragastrically given the same volume of normal saline, the rats in Jiedu-Qingfei group were given 8 mL/kg Jiedu-Qingfei mixture daily for 4 weeks, and the rats in psoitive control group were given dexmethasone sodium phosphate (0.5 mg·kg^-1·d^-1). After the experiment, the rats were killed. The serum and bronchoalveolar lavage fluid (BALF) were collected for detecting the levels of interleukin-12 (IL-12), IL-13 and TNF-α by ELISA. The right lung tissues were used for pathological observation and HE staining, while the left lung tissues were used to detect the expression of NF-κB p50, I-κBα and p38 mitogen-activated protein kinase (p38 MAPK) at mRNA and protein levels. RESULTS: The results of MP nucleic acid detection showed that all the rats except blank control group were MP nucleic acid positive, indicating that the rat model of MP infection was successfully established. On the 1st day of the treatment, the pathological scores of the lung tissues in model group and Jiedu-Qingfei group were significantly higher than those in blank control group (P<0.05). After treatment, the pathological scores of the lung tissues in mo-del group were significantly higher than those in blank control group and Jiedu-Qingfei group. The levels of IL-12 in the serum and BALF in model group were significantly lower than those in blank control group after MP infection (P<0.05), while those after treatment with Jiedu-Qingfei mixture were significantly higher than those in model group (P<0.05). The levels of IL-13 and TNF-α in the serum and BALF of MP-infected rats were increased significantly, while those after treatment with Jiedu-Qingfei mixture were significantly lower than those in model group (P<0.05). The mRNA expression levels of NF-κB p50 and p38 MAPK in model group were increased significantly (P<0.01). After treatment, the mRNA expression levels of NF-κB p50 and p38 MAPK were decreased significantly compared with model group (P<0.01). The mRNA expression level of I-κBα in model group was significantly lower than that in control group. After treatment, the mRNA expression of I-κBα in Jiedu-Qingfei group was significantly higher than that in model group (P<0.05). The protein levels of NF-κB p50 and p38 MAPK in the lung tissues of model group were significantly higher than those of blank control group. After treatment, the protein expression of NF-κB p50 and p38 MAPK was decreased significantly. The protein level of I-κBα in model group was significantly lower than that in blank control group, and after treatment with Jiedu-Qingfei mixture, the protein expression level of I-κBα was increased significantly (P<0.05). CONCLUSION: Jiedu-Qingfei mixture may attenuate lung tissue inflammation caused by MP through NF-κB and p38 MAPK pathways.     

Effect of ruthenium-polypyridine complex on apoptosis of gastric cancer SGC-7901 cells

AIM:To study the effect of ruthenium-pyridine complex Ru1 on apoptosis of gastric cancer SGC-7901 cells. METHODS:MTT assay and crystal violet staining method were used to detect the viability and cell number of SGC-7901 cells treatment with Ru1. Annexin V-FITC and PI staining was performed to test the apoptosis rate of SGC-7901 cells. The protein expression of Bax and Bcl-2 was detected by Western blot. RESULTS:The results of MTT assay and crystal violet staining showed that the ruthenium-pyridine complexes significantly reduced the viability and cell number of SGC-7901 cells. Treatment with Ru1 for 24 h significantly increased the apoptotic rate of SGC-7901 cells (P<0.05). Ru1 up-regulated the expression of Bax protein and down-regulated the expression of Bcl-2 protein in the SGC-7901 cells (P<0.05). CONCLUSION:Ru1 induces apoptosis of SGC-7901 cells by affecting the expression of Bax and Bcl-2 proteins.     

Effect of integrin β1 on multidrug resistance in gastric cancer SGC-7901 cells

AIM: To study the effect of integrin β1 on multidrug resistance in gastric cancer and its possible mechanisms. METHODS: The expression of integrin β1 at mRNA and protein levels in the SGC-7901 cells and SGC-7901/DDP cells was determined by qPCR and Western blot. The expression of integrin β1 in the SGC-7901/DDP cells was silenced by antisense oligodeoxynucleotide. The cell viability was detected by the CCK-8 assay, the cell apoptosis were analyzed by flow cytometry, and the protein levels of integrin β1, Bcl-2/Bax, cleaved caspase-3/caspase-3, cytochrome C (Cyt-C) and p-AKT/AKT were determined by Western blot.RESULTS: The expression of integrin β1 at both mRNA and protein levels was significantly upregulated in SGC-7901/DDP cells. The expression of integrin β1 was increased in SGC-7901 cells treated with chemotherapeutic agents such as cisplatin, paclitaxel and 5-fluorouracil. Knockdown of integrin β1 induced apoptosis of SGC-7901/DDP cells with an increased sensitivity to the chemotherapeutic agents. Meanwhile, knockdown of integrin β1 downregulated the protein levels of Bcl-2/Bax, p-AKT^Ser473 and p-AKT^Thr308, while promoted the release of Cyt-C and upregulated the protein level of cleaved caspase-3. CONCLUSION: Knockdown of integrin β1 increases the sensitivity of SGC-7901/DDP cells to the chemotherapeutic agents, and promotes the cell apoptosis via mitochondrial apoptosis pathway. The mechanism may be related to the attenuation of AKT pathway by inhibiting phosphorylations of AKT at Ser473 and Thr308.