Protective effect of SIRT1 on rat mesangial cells by decreasing high glucose-induced acetylation of NF-κB p65

AIM: To investigate the effects of silent information regulator 1 (SIRT1) on high glucose-induced acetylation of NF-κB p65 subunit and its protective role in rat mesangial cells. METHODS: Rat mesangial cells were cultured in DMEM supplemented with 10% FBS and were divided into control group, mannitol group, high glucose group, resveratrol group and SIRT1 RNAi group. The cell viability was determined by MTT assay. The mRNA expression of SIRT1, monocyte chemoattratant protein 1 (MCP-1), vascular cell adhesion molecule 1 (VCAM-1-1), tumor necrosis factor α (TNF-α), transforming growth factor β1 (TGF-β1) was analyzed by real-time quantitative PCR. The protein expression of SIRT1 and the acetylation of NF-κB p65 subunit were determined by Western blotting. The protein concentrations of MCP-1, VCAM-1, TNF-α, TGF-β1 and malondialdehyde (MDA) were detected by ELISA. RESULTS: The cell viability, superoxide dismutase (SOD) activity, and the expression of SIRT1 at mRNA and protein levels were decreased by high glucose treatment as compared with control group. The acetylation of NF-κB p65 subunit was significantly increased after interfered with high glucose, resulting in the increase in the secretion of MCP-1, VCAM-1, TNF-α and TGF-β1. Resveratrol decreased high glucose-induced acetylation of NF-κB p65 subunit. However, silencing SIRT1 significantly enhanced the acetylation of NF-κB p65 subunit and the expression of MCP-1, VCAM-1, TNF-α and TGF-β1. CONCLUSION: SIRT1 remarkably inhibits the inflammatory reactions by deacetylating NF-κB p65, suggesting that SIRT1 is a possible target for preventing diabetic nephropathy.     

Activation of NF-κB in rat vascular smooth muscle cells by autoantibodies against α1-adrenergic receptor from hypertensive patients

AIM：To study the effects of autoantibodies against α1-adrenergic receptor (α1-AAs) isolated from the hypertensive patients, which showed the agonist-like activity similar to norepinephrine, on the signal mechanism of vascular smooth muscle cells (VSMCs) isolated from rat thoracic aorta. METHODS：Rat VSMCs were cultured and identified. The serum of hypertensive patients was purified by immunoaffinity chromatography. The autoantibodies were detected by ELISA and used to activate the cells with the titer of 1∶80. The total protein was extracted and the expression of NF-κB in different treatment groups was detected by Western blotting. Meanwhile, the activation of NF-κB in the nucleus was analyzed by immunofluorescence method. RESULTS：The expression of NF-κB in VSMCs was obviously higher in α1-AAs group than that in control group. Meanwhile, the expression of NF-κB was inhibited by prasozin and PDTC. The autoantibodies caused a significant increase in NF-κB expression in the nucleus. The fluorescence intensity in α1-AAs group was high than that in control group and α1-AAs+prasozin group (P<0.01). CONCLUSION:The α1-AAs from hypertensive patients increase NF-κB expression in rat VSMCs.     

Hydrogen sulfide ameliorates high glucose-induced endothelial cell senescence by suppressing oxidative stress

AIM：To explore the effect of hydrogen sulfide on the senescence of human umbilical vein endothelial cells (HUVECs) induced by high glucose. METHODS：Senescence model was established by treating HUVECs with 33 mmol/L glucose for 48 h. The parameters were detected to demonstrate the effect of hydrogen sulfide on senescence and the mechanism involved was also investigated. RESULTS：In the cells treated with high glucose, the proliferation was attenuated with a higher number of senescence-associated β-galactosidase (SA-β-Gal) positive cells, and plasminogen activator inhibitor 1 (PAI-1) protein expression, malondialdehyde (MDA) production and NF-κB p65 activity were increased significantly, but the expression of superoxide dismutase 1 (SOD1) was decreased. However, the cell number and SOD1 expression were increased, and the number of SA-β-Gal positive cells, PAI-1 protein expression, MDA production and the activity of NF-κB p65 were decreased after sodium hydrosulfide (100 and 200 μmol/L) treatment.CONCLUSION：Exo-genous hydrogen sulfide prevents HUVECs against high glucose-induced senescence by suppressing oxidative stress and NF-κB p65 activity.     

Protective effects of Zhenwu decoction on kidney injury of diabetic rats induced by streptozotocin

AIM：To investigate the effects of Zhenwu decoction (ZWD) on the expression of α-smooth muscle actin (α-SMA) and NF-κB in diabetic nephropathy (DN) rats. METHODS：Diabetic rat model was induced by intrape-ritoneal injection of streptozotocin (STZ), and the animals were randomly divided into STZ group (n=22) and STZ+ZWD group (n=23). The normal rats served as control (n=16). All rats were sacrificed on 8 weeks after modeling. Biochemical assay and pathological observation (HE staining and transmission electron microscopy) were used to evaluate the effects of Zhenwu decoction on the renal function and pathological morphology. The body weight, renal index, blood glucose, total urinary protein in 24 h, and superoxide dismutase (SOD), malondialdehyde (MDA),inducible nitric oxide synthase (iNOS) were determined as well. Western blotting was used to observe the effects of Zhenwu decoction on the expression of α-SMA and NF-κB in diabetic nephropathy (DN) rats. RESULTS：Compared with normal group, the renal index, blood glucose concentration, total urinary protein in 24 h, blood urea nitrogen (BUN), serum creatinine (SCr) and MDA were significantly higher and body weight was lower in DN rats (P<0. 05). Pathological examination of the kidneys in DN group showed glomerular hypertrophy, glomerular basement membrane thickening, tubular epithelial cell degeneration, mesangial matrix proliferation, protein cast formation in some renal tubules. The protein expression levels of α-SMA and NF-κB were markedly increased (P<0.05). After ZWD treatment, the level of renal index, total urinary protein in 24 h, BUN, SCr and the expression of α-SMA and NF-κB at the protein level were significantly decreased (P<0.05). The renal histological injury in ZWD group was significantly ameliorated. CONCLUSION：Zhenwu decoction might protect kidney against STZ-induced injury via decreasing the expression of α-SMA and NF-κB.     

Effect of propolis on the expression of CD54 and activation of NF-κB p65 of lung tissue in acute lung injury rats

AIM: To study the effect of propolis on the expression of CD54 and activation of NF-κB p65 in lung tissue of acute lung injury (ALI) rats. METHODS: 40 male Wistar rats were divided into 5 groups: normal control, model control, dectancyl group, water soluble derivative of propolis (WSP) group and ethanol extracted propolis (EEP) group. ALI animal model was performed by oleic acid and LPS twice attack. The pathologic slice was observed with light microscope and the NF-κB p65 activity and CD54 expression were tested by immunohistochemistry (SABC and SP). RESULTS: Both EEP and WSP antagonized the lung edema, decreased the inflammation and inhibited the expression of CD54 and activation of NF-κB p65. CONCLUSION: The increase in the expression of CD54 and the activation of NF-κB p65 in the lung tissues of ALI were involved in the formation of ALI. Propolis ameliorated the lung damage, which maybe related to the inhibition of CD54 expression and NF-κB p65 activation.     

Effects of eicosapentaenoic acid on expression of nuclear factor κB and release of cytokines in human umbilical vein endothelial cells stimulated by lipopolysaccharide

AIM: To investigate the effects of eicosapentaenoic acid(EPA) on the expression of nuclear factor kappa B(NF-κB) and release of vascular endothelial growth factor(VEGF), IL-1α and IL-6 in cultured human umbilical vein endothelial cells(HUVECs) stimulated by lipopolysaccharide(LPS).METHODS: HUVECs were obtained from cell strain and cultured in vitro. HUVECs were divided into 4 groups: control group, LPS group, 0.030 g/L EPA treatment group and 0.050 g/L EPA treatment group. The cells were cultured with LPS alone in LPS group and incubated with EPA for 1 h in the EPA pretreatment groups at the concentrations of 0.030 g/L and 0.050 g/L before LPS stimulation. Twenty-four hours after stimulated by LPS, the protein expression of NF-κB p65 in HUVECs were assessed by Western blotting analysis at different time points. The production of VEGF, IL-1α and IL-6 in cultured HUVECs was evaluated by ELISA. The effects of EPA on the protein expression of NF-κB p65 and the production of VEGF, IL-1α and IL-6 in HUVECs challenged by LPS were also determined.RESULTS: Compared with control group, the protein expression of NF-κB p65 was significantly increased in HUVECs induced by LPS and was inhibited by EPA. Compared with control group, the protein expression of VEGF, IL-1α and IL-6 was dramatically increased in HUVECs induced by LPS and most of the increase was inhibited by EPA.CONCLUSION: LPS enhances the protein expression of NF-κB and the release of VEGF, IL-1α and IL-6. EPA inhibits the protein expression of NF-κB, and the production of VEGF and the inflammatory cytokines in cultured HUVECs stimulated by LPS, indicating that EPA may be useful for preventing and treating neovascular and inflammatory diseases.     

Downregulation of DEK induces cell apoptosis via inhibition of NF-κB signaling pathway in gastric carcinoma SGC-7901 cells

AIM: To investigate the effect of DEK downregulation on the apoptosis of gastric carcinoma SGC-7901 cells, and to explore its associations with NF-κB signaling pathway and apoptosis related proteins. METHODS: SGC-7901 cells with different treatments were divided into 3 groups including untreated group, control siRNA group and DEK siRNA group. The expression of DEK at mRNA and protein levels in the SGC-7901 cells was detected by real-time PCR and Western blot. The cell apoptosis was examined by flow cytometry. Furthermore, the activities of caspase-3 and caspase-9 in the SGC-7901 cells were investigated by Caspase-Glo^®-3/9 kit. Finally, the expression of key regulatory protein p65 of NF-κB signaling pathway and apoptosis-related proteins Bcl-2 and Bax in the SGC-7901 cells was investigated by Western blot. RESULTS: Compared with untreated group and control siRNA group, the expression of DEK at mRNA and protein levels was significantly downregulated in DEK siRNA group (P<0.05). In addition, the ratios of early phase apoptosis and total apoptosis in DEK siRNA group were markedly higher than those in untreated group and control siRNA group (P<0.05). Most notably, the decrease in p65 and Bcl-2 proteins, increase in Bax protein and the increases of caspase-3 and caspase-9 activities were observed in DEK siRNA group. CONCLUSION: Downregulation of DEK mediates cell apoptosis of gastric carcinoma may be tightly associated with NF-κB signaling pathway.     

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.     

IL-1β induces human mesangial cell injury via exacerbating lipid-induced endoplasmic reticulum stress

AIM：To investigate the molecular mechanism that interleukin-1 beta (IL-1β) exacerbates lipid-induced endoplasmic reticulum stress (ERS) and the injury of human mesangial cells (HMCs). METHODS：HMCs were cultured and divided into control group, low-density lipoprotein (LDL) group, IL-1β+LDL group and 4-phenyl butyric acid (4-PBA)+IL-1β+LDL group. Oil red O staining was used to evaluate the accumulation of lipid droplet in the cells. The mRNA levels of glucose-regulated protein 78(GRP78), protein kinase R-like endoplasmic reticulum kinase (PERK) and α-smooth muscle actin (α-SMA) were examined by real-time PCR. Immunocytochemistry was used to observe GRP78 expression. The protein level of NF-κB p65 was measured by Western blotting. The releases of IL-6 and TGF-β1 in the culture supernatants of HMCs were detected by ELISA. RESULTS：Compared with LDL group, the intracellular lipid accumulation, the mRNA levels of GRP78 and PERK, the protein expression of GRP78 and NF-κB p65, and the release of IL-6 were significantly increased in IL-1β+LDL group. Dramatically reduced intracellular lipid accumulation, down-regulated GRP78 and PERK mRNA expression, decreased protein levels of GRP78 and NF-κB p65, and suppressed IL-6 release were observed in 4-PBA+IL-1β+LDL group as compared with IL-1β+LDL group. The mRNA level of α-SMA was higher in IL-1β+LDL group than that in LDL group, and that in 4-PBA+IL-1β+LDL group was significantly depressed. CONCLUSION：IL-1β exacerbates lipid-induced ERS, thus promoting the injury of HMCs.     

Roles of nuclear factor-κB in the development of rat pancreatic fibrosis mediated by angiotensin II

AIM: To determine the effects of NF-κB on the development of rat pancreatic fibrosis mediated by angiotensin II. METHODS: Spraque-Dawley rats (200-300g) were randomly divided into normal group, control group and losartan-treatment group. Pancreatic fibrosis was induced by injection of 2% TNBS into biliopancreatic duct. Rats in losartan-treatment group and control group were respectively treated with losartan (10 mg·kg^-1·d^-1) by gavage and the same volume of saline vehicle. The expression, distribution, and activation of NF-κB were studied by Western blot, immunohistochemistry and TransAM^TM. Toluidine blue staining and transmission electron microscopy were also used to observe the number, distribution and degranulation of mast cells. In addition, RT-PCR was performed to detect the intrapancreatic ICAM-1 mRNA expression. RESULTS: The expression and activity of intrapancreatic NF-κB p65 protein were significantly increased on day 3 after operation, reaching peak on day 7 [(0.406±0.086)mg/g total protein].. Mast cell activation was observed and ICAM-1 mRNA levels on day 3 and 7 were up-regulated in control group. Losartan treatment inhibited NF-κB expression and activation, reduced mast cell infiltration and degranulation and decreased ICAM-1 mRNA expression compared with control rats. CONCLUSION: It might be associated with the expression and activation of NF-κB that angiotensin II mediates inflammation and fibrosis in the early stage of pancreatic fibrosis.     

Expression of cyclooxygenase-2 in IL-1β-stimulated mesangial cells is medicated by NF-κB/IκB signal pathway

AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE₂ concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE₂ production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway.     

Inhibition of HMGB1 expression promotes apoptosis of hemangioma endothelial cells

AIM: To investigate the effect of inhibiting high-mobility group box protein 1 (HMGB1) expression on the viability and apoptosis of hemangioma endothelial cells (HemECs). METHODS: Human HemECs were isolated and cultured, and HMGB1 small interfering RNA (HMGB1-siRNA) was transfected into the cells. The cell viability was detected by CCK-8 assay. The apoptosis and reactive oxygen species (ROS) content were analyzed by flow cytometry. The protein levels of HMGB1, NF-κB p65, p-IκBα, cyclin D1 and survivin were determined by Western blot. RESULTS: The protein expression of HMGB1 in the HemECs transfected with HMGB1-siRNA was significantly lower than that in blank control group (P<0.05). Compared with NC group, the cell viability was decreased significantly in the HemECs transfected with HMGB1-siRNA, the apoptotic rate was significantly increased, the content of ROS increased significantly, and the protein levels of NF-κB p65, p-IκBα, cyclin D1 and survivin were significantly decreased (P<0.05). After exposure to NF-κB signaling pathway inhibitor PDTC, the cell viability was inhibited, the apoptosis was increased, ROS content, and the protein levels of NF-κB p65, p-IκBα, cyclin D1 and survivin were down-regulated significantly, as compared with si-HMGB1 group (P<0.05). CONCLUSION: Inhibition of HMGB1 reduces the viability of HemECs and induces apoptosis by increasing the content of ROS and down-regulating the activity of NF-κB signaling pathway.     

Action of NF-κB p65 in renal interstitium in rats with active Heymann nephritis

AIM: To study the action of NF-κB p65 in tubule-interstitium in rats with active Heymann nephritis(AHN). METHODS: Twenty female Wistar rats in 6-8 weeks of age were divided into two groups. The nephritis was induced with Fx1A/CFA by subcutaneous injection and with CFA as control. After rats were killed, the activation of NF-κB p65 in renal tissue was observed by immune histochemistry. RESULTS: The lesion score of renal interstitium and activation of NF-κB p65 of renal tubule in rats with AHN was higher than those of control group(P<0.01). A positive correlation was found between the positive rate of NF-κB p65 in renal tubule and the lesion score of renal interstitium, the levels of urinary protein (r=0.7138 and 0.6376, P<0.05).CONCLUSION: The activation of NF-κB p65 participates in the damage of pathophysiological functions of tubule-interstitium in AHN.     

Ubiquitin-dependent degradation of SnoN/Ski protein in glomerular mesangial cells induced by high glucose

AIM: To observe the protein expression of SnoN/Ski and ubiqutin ligase Arkadia in rat glomerular mesangial cells (GMCs) exposed to the high glucose. METHODS: Cultured rat glomerular mesangial HBZY-1 cells were divided into control group, 20 mmol/L glucose group, 30 mmol/L glucose group, 30 mmol/L glucose+MG132 group (culture medium containing 30 mmol/L glucose and 0.5 μmol/L specific proteasome inhibitor MG132), and mannitol group. The expression levels of SnoN, Ski and Arkadia were measured by Western blotting analysis, immunofluorescence and laser scanning confocal microscopy. RESULTS: In control GMCs, the expression of SnoN/Ski was rich and Arkadia was weak. After stimulated with high glucose, the expression of SnoN/Ski was decreased and Arkadia was gradually increased (P<0.05). Compared with high glucose group, the levels of SnoN/Ski and Arkadia were mostly reverted by adding the proteasome inhibitor MG132 at concentration of 0.5 μmol/L (P<0.01). The expression levels of SnoN/Ski and Arkadia were not significantly changed in mannitol group in comparison with control group (P>0.05). CONCLUSION: High glucose decreases the expression of SnoN/Ski through ubiquitin-dependent degradation of SnoN/Ski. The degradation of SnoN/Ski mediated by Arkadia may play an important role in the pathogenesis of diabetic nephropathy.     

Influence of ginsenoside Re on vascular intima hyperplasia and NF-κB p65 signaling pathway in balloon-injured rats

AIM: To investigate the inhibitory effect of ginsenoside Re on intimal hyperplasia induced by balloon-injury and to explore the role of NF-κB p65 signaling pathway in the process. METHODS: SD rats(n=40) were divided into 5 groups randomly: sham operation group, model group, low-dose ginsenoside Re group, middle-dose ginsenoside Re group and high-dose ginsenoside Re group. The carotid artery intima injury model was established by 2F balloon catheters in all groups except the sham operation group. The day after modeling, the animals in model group and sham operation group were administered intragastrically with distilled water, and the rats in low-dose, middle-dose and high-dose ginsenoside Re groups were given ginsenoside Re at doses of 12.5 mg/kg, 25mg/kg and 50 mg/kg, respectively. After 14 continuous days, the morphological changes of the injured arteries were observed by HE staining and the lumen area, intima area and media area as well as the ratio of intimal area/media area were determined. The expression of tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) were detected by real-time PCR. The proliferating cell nuclear antigen(PCNA) and nuclear factor-kappa B(NF-κB) p65 were examined by immunohistochemistry.RESULTS: Compared with sham operation group, the vessel cavity was narrowed(P<0.01), the mRNA levels of TNF-α and IL-1β, and the protein expression of PCNA and NF-κB p65 were increased in model group(P<0.05). Compared with model group, the vascular intimal hyperplasia was alleviated obviously(P<0.05), and the mRNA levels of TNF-α and IL-1β, and protein expression of PCNA and NF-κB p65 were decreased in medium and high-dose ginsenoside Re groups(P<0.05). CONCLUSION: Ginsenoside Re inhibits the vascular neointimal hyperplasia induced by balloon-injury in rats, and the molecular mechanism may be related to the inhibition of NF-κB p65 signaling pathway.     

Expression and significance of TLR4/NF-κB in pulmonary vascular remodeling in smoking rats

ATM: To observe the expression of Toll-like receptor 4 (TLR4), nuclear factor-κB subunit P65 protein (NF-κB P65) and proliferating cell nuclear antigen (PCNA) in the pulmonary vascular tissues of the rats exposed to smoke, and to explore the possible mechanism of TLR4/NF-κB signaling pathway in pulmonary vascular remodeling. METHODS: SPF male healthy rats (n=48) were randomly divided into control group, smoke exposure for 4 weeks group (S4 group), smoke exposure for 8 weeks group (S8 group) and smoke exposure for 12 weeks group (S12 group), with 12 rats in each group. HE staining was used to observe the morphological changes of pulmonary vessels, and then the pulmonary vascular wall area/total vascular area (WA%) and vascular wall thickness/vascular external diameter (WT%) were measured by the medical image analysis system. The expression of TLR4, NF-κB P65 and PCNA in the pulmonary vascular tissues was detected by immunohistochemical staining. The protein content was expressed by the average integral absorbance. The mRNA expression of TLR4 in the pulmonary vessels was detected by RT-qPCR. The relationships between WA%, WT%,TLR4 protein, TLR4 mRNA, P65 protein, PCNA protein and pulmonary vascular remodeling, and another relationships between WA%, WT%, P65 protein, PCNA protein and TLR4 protein were analyzed.RESULTS: The WA% and WT% in smoke exposure groups significantly increased compared with control group, and the ratio was proportional to the time of smoke exposure. The protein expression of TLR4, p65 and PCNA, and the mRNA expression of TLR4 in smoke exposure groups also increased significantly compared with control group. CONCLUSION: The extent of pulmonary vascular remodeling in the rats increases when the protein expression of TLR4 is up-regulated. There is a positive correlation between pulmonary vascular remodeling and the protein expression of TLR4 and NF-κB P65. Pulmonary vascular remodeling may be related to the activation of TLR4/NF-κB signaling pathway.     

Role of damaged mitochondria in Vibrio vulnificus induced dendritic cell apoptosis

AIM： To investigate the role of damaged mitochondria in dendritic cell (DC) apoptosis induced by Vibrio vulnificus (Vv) and its possible mechanism. METHODS：DC2.4 cells were co-cultured with Vv 1.1758 strain. Fluorescent probes DCFH-DA and Fluo-8-AM were used to detect reactive oxygen species (ROS) and intracellular Ca2+ concentration in the invaded cells, respectively. The cellular apoptotic rates and mitochondrial membrane potential (Δψm) were measured by flow cytometry. The expression of nuclear factor-kappa B p65 (NF-κB p65) and tumor necrosis factor-alpha (TNF-α) was detected by Western blotting. RESULTS： Vv 1.1758 induced DC2.4 cell apoptosis. Vv 1.1758 bacteria invaded into the DC2.4 cells by binding with cellular membrane though the end of the body. In the invaded DC2.4 cells, the visible mitochondrial damage, elevated ROS and intracellular Ca2+ levels, and declined Δψm were presented. After 1 h of co-culture, NF-κB p65 began to rise and reached the peak at 5 h, and then slightly decreased at 6 h. The TNF-α level increased after 2 h of co-culture and reached the peak at 6 h. CONCLUSION： The damaged mitochondria play an important role in DC apoptosis induced by Vv, and its possible mechanism may associate with the elevation of ROS and intracellular Ca2+ level, and the declined Δψm. Meanwhile, NF-κB p65 and TNF-α are potential critical signaling molecules in the process of apoptosis.     

Effects of diterpenoid C from ether extract of Radix Curcumae on nuclear factor-κB activity in LPS-induced human gastric adenocarcinoma SGC7901 cells

AIM: To observe the effects of diterpenoid C from ether extract of Radix Curcumae (RC) on the activity of nuclear factor-κB in human gastric adenocarcinoma SGC7901 cells stimulated with lipopolysaccharide (LPS). METHODS: SGC7901 cells were normally cultured, induced by LPS, or treated with LPS plus RC. The protein expression of IKKα, IKKβ, p65, phosphorylated p65 and phosphorylated IκBα was assayed by Western blotting. NF-κB DNA binding activity was determined by electrophoretic mobility shift assay. RESULTS: RC reduced the protein expression of IKKα, IKKβ, p65, phosphorylated p65 and phosphorylated IκBα induced by LPS. NF-κB DNA binding activity increased much greatly by LPS stimulation, while RC resisted the action of LPS. CONCLUSION: RC may attenuate the secretion of inflammatory cytokines by inhibiting the activation of NF-κB signaling pathway.