Aβ1-40 induces inflammation and phenotypic switching via activation of MAPKs signaling pathway in vascular smooth muscle cells

AIM To investigate the effects of amyolid β-protein 1-40 （Aβ1-40） on inflammation, viability, migration and phenotypic switching in vascular smooth muscle cells （VSMCs）, and to analyze the underlying mechanisms. METHODS The VSMCs were treated with Aβ1-40 at different concentration gradients for appropriate time. CCK-8 and Transwell assays were performed to evaluate the viability and migration ability of VSMCs. The levels of inflammatory factors including interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α）, phenotypic switching-related proteins including α?smooth muscle actin （α?SMA）, osteopontin （OPN） and Krüppel?like factor 4 （KLF4）, and mitogen-activated protein kinases （MAPKs） signaling pathway-related proteins including p-p38 MAPK, p-ERK1/2 and p-JNK were determined by Western bolt. RESULTS After Aβ1-40 treatment, the levels of inflammatory factors IL-1β and TNF-α in the VSMCs were significantly increased （P<0.05）, and the expression of phenotypic switching-related proteins was altered, as indicated by down-regulation of α?SMA and up-regulation of OPN and KLF4 （P<0.05）. Treatment with Aβ1-40 within a certain concentration range promoted the viability and migration of the VSMCs. In addition, the protein levels of p-p38 MAPK, p-ERK1/2 and p-JNK were significantly increased by Aβ1-40 treatment （P<0.05）. Furthermore, pretreatment with specific inhibitors of MAPKs pathway significantly reduced the levels of IL-1β and TNF-α （P<0.05）, and inhibited the phenotypic switching, as indicated by up-regulation of α?SMA and down-regulation of OPN and KLF4 （P<0.05）. CONCLUSION Treatment with Aβ1-40 induces the inflammation and phenotypic switching in VSMCs via activation of MAPKs signaling pathway.     

Alternariol induces DNA polymerase β expression via the PKA-CREB pathway in NIH3T3 cells

AIM: To investigate the signal transduction induced DNA polymerase β expression by alternariol(AOH) in NIH3T3 cells. METHODS: The NIH3T3 cells were treated with 15 μmol/L AOH for 16 h or the cells were pretreated with an inhibitor of PKA (H89) for 1 h, and then exposed to AOH. The changes of DNA polβ expression and phospho-CREB in the cells with different treatments were determined by Western blotting and immunocytochemistry analysis. RESULTS: The expression of DNA polymerase β and phospho-CREB in NIH3T3 cells induced by AOH were significantly higher than that in control group (P<0.05). However, H89 partly blocked the AOH-induced phospho-CREB and DNA polβ expression. CONCLUSION: Alternariol up-regulates DNA polymerase β expression via the PKA-CREB pathway in NIH3T3 cells.     

Tanshinone ⅡA attenuates doxorubicin-induced injury in H9c2 cardiomyocytes via AMPK-mediated autophagy

AIM: To investigate the effect of tanshinone ⅡA on doxorubicin-induced rat H9c2 cardiomyocyte injury. METHODS: The H9c2 cardiomyocytes were treated with tanshinone ⅡA and/or doxorubicin with or without AMPK inhibitor dorsomorphin. The cell viability was measured by CCK-8 assay, the LDH release was examined for evaluating the cell injury, autophagy was analyzed by immunofluorescence staining, and AMPK activation was determined by Western blot. RESULTS: Compared with control group, the viability of H9c2 cells was decreased, the release of LDH was increased, the autophagy degree was increased, and AMPK activation was inhibited after treatment with doxorubicin (P<0.05). Compared with doxorubicin group, the treatment with tanshinone ⅡA restored the cell viability, reduced the release of LDH, further increased autophagy degree, and activated AMPK in the H9c2 cells (P<0.05). AMPK inhibitor dorsomorphin attenuated the abilities of tanshinone ⅡA to restore the cell viability, reduce the release of LDH, and increase autophagy degree in the H9c2 cells (P<0.05). CONCLUSION: Tanshinone ⅡA attenuates doxorubicin-induced injury in H9c2 cardiomyocytes, and its mechanism might be related to AMPK-mediated autophagy, which provides experimental and theoretical basis for the clinical application of tanshinone ⅡA in the prevention and treatment of doxorubicin-induced cardiomyocyte injury.     

RIP1-mediated necroptosis regulates inflammatory response of renal tubular epithelial cells via NF-κB signaling pathway

AIM To investigate the effect of receptor-interacting protein 1 (RIP1)-mediated necroptosis on human kidney proximal tubular cell inflammation and its related mechanisms. METHODS Human kidney proximal tubular HK-2 cells were cultured in vitro, and stimulated with tumot tumor necrosis factor-α (TNF-α) and Z-VAD-FMK for 24 h. Lactate dehydrogenase (LDH) cytotoxicity assay was used to detect the percentage of necrosis. Western blot was used to detect the protein expression of RIP1, IKK-α and NF-κB p65. The protein levels of interleukin-1β (IL-1β) and monocyte chemoattractant protein-1 (MCP-1) were determined by Western blot and ELISA. Real-time PCR was used to detect the mRNA expression level of NF-κB p65. Furthermore, the RIP1 inhibitor necrostatin-1 (Nec-1) and the NF-κB specific inhibitor ammonium pyrrolidinedithiocarbamate (PDTC) were used, and the above indicators were also detected. RESULTS Compared with control group, the protein level of RIP1 was increased in TNF-α combined with Z-VAD-FMK stimulation group (T/Z group). The protein levels of IKK-α and NF-κB p65 were obviously increased, and the release of LDH was increased (P<0.01). Western blot and ELISA showed that the expression levels of IL-1β and MCP-1 were significantly increased (P<0.01). Real-time PCR showed that the mRNA expression level of NF-κB p65 was also obviously increased. After Nec-1 or PDTC stimulation (T/Z+N group or T/Z+P group), the release of LDH, and the expression levels of inflammation-related indicators IL-1β and MCP-1 were significantly decreased. The protein expression levels of IL-1β and MCP-1 were further reduced after treatment with the above 2 stimulati (T/Z+P/N group). CONCLUSION Under T/Z condition, RIP1-mediated necroptosis plays an important role in renal tubular inflammatory response, which may be partly achieved by regulating the activation of NF-κB signaling pathway.     

AngiotensinⅡ activates autophagy pathway through elevating ROS level in vascular endothelial cells

AIM: To evaluate the effects of angiotensinⅡ (AngⅡ) on autophagy induction in vascular endothelial cells. METHODS: Human vascular endothelial EA.hy926 cells were used in the study. Intracellular reactive oxygen species (ROS) levels were detected by a microplate reader after the cells were treated with AngⅡ (10^-7 mol/L) or AngⅡ combined with antioxidant N-acetyl-L-cysteine (NAC,50 μmol/L) for 24 h. The protein levels of LC3-Ⅱ was detected by Western blotting after the cells were stimulated by different concentrations (10^-8, 10^-7, 10^-6 mol/L) of AngⅡ for 24 h or by AngⅡ (10^-7mol/L) for different time (0 h, 6 h, 12 h, 24 h, 36 h). The number of autophagosomes was evaluated by fluorescence microscopy after stained with acridine orange. Similarly, the protein level of LC3-Ⅱ and the number of autophagosomes were detected after treated with AngⅡ(10^-7mol/L), AngⅡ combined with autophagy inhibitor 3-methyladenine (3-MA) at concentration of 2 mmol/L or AngⅡ combined with NAC at concentration of 50 μmol/L. RESULTS: Intracellular ROS level and LC3-Ⅱprotein level were significantly increased (P<0.05) after the cells were treated with AngⅡ, accompanied by the significant increase in the number of autophagosomes. AngⅡ-induced autophagy (as showed both in LC3-Ⅱprotein level and autophagosomes) was dramatically down-regulated by the treatment with 3-MA or NAC in EA.hy926 cells (P<0.05). CONCLUSION: AngⅡ induces autophagy through elevating ROS levels in EA.hy926 cells.     

AngⅡ/AT1R pathway activates PP2A to down-regulate p-eNOS (Ser1177) in human umbilical vein endothelial cells

AIM: To investigate whether angiotensinⅡ (AngⅡ)/angiotensin Ⅱ type 1 receptor (AT₁R) pathway down-regulates endothelial nitric oxide synthase (eNOS) Ser1177 phosphorylation level in human umbilical vein endothelial cells by activating protein phosphatase 2A (PP2A).METHODS: Human umbilical vein endothelial cells were randomly divided into normal control (control) group, Ang Ⅱ group, candesartan (CAN; specific AT₁R blocker) group and CAN pretreatment+AngⅡ group. The protein levels of total eNOS, p-eNOS (Ser1177), PP2Ac, I₂^PP2A and p-PP2Ac (Tyr307) were determined by Western blot. The content of NO in the cell culture medium was detected by chemical colorimetry.RESULTS: Compared with control group, the level of p-eNOS (Ser1177) and the content of NO decreased (P<0.05). Compared with the same concentration of AngⅡ group, CAN pretreatment increased the level of p-eNOS (Ser1177) and the content of NO (P<0.05), but the protein expression of eNOS showed no significant difference. Compared with control group, the levels of p-PP2Ac (Tyr307) and I₂^PP2A decreased (P<0.05). Compared with the same concentration of AngⅡ group, CAN pretreatment increased the levels of p-PP2Ac (Tyr307) and I₂^PP2A (P<0.05), but the protein expression of PP2Ac showed no significant difference.CONCLUSION: AngⅡ down-regulates the level of p-eNOS (Ser1177), and decreases the production of NO in human umbilical vein endothelial cells via AT₁R pathway. This effect may be related to the reduction of p-PP2Ac (Tyr307) and protein expression of I₂^PP2A, which results in the enhancement of PP2A activity. Pretreatment with AT₁R blocker CAN increases p-PP2Ac (Tyr307) level and I₂^PP2A protein expression, thus reducing the PP2A activity, and ultimately restoring eNOS Ser1177 phosphorylation level and eNOS activity.     

Effect of high glucose toxicity on JNK pathway,cell viability and apoptosis in pancreatic β-cell line INS-1

AIM: To investigate the effect of high glucose toxicity on JNK pathway and cell function of INS-1 cells.METHODS: Cultured INS-1 cells with or without IGF-1 exposure, were treated with glucose at 3 concentrations (5.6 mmol/L, 11.2 mmol/L and 33.3mmol/L), respectively. MTT was used to measure the cell viability. Apoptosis was determined by immuno-fluorescence and flow-cytometry analysis. The serine 270 phosphorylation of IRS and phosphorylation of JNK in INS-1 cells were detected in the presence or absence of SP600125 treatment.RESULTS: The cell viability decreased and apoptosis increased with elevated glucose concentrations. The percentage of apoptosis cells was 11.3% in 5.6 G group, 12.7% in 11.2 G group and 28.2% in 33.3 G group. There was remarkable increase in apoptosis in 33.3 G group with a 2.49-fold increase to the cells in the basal 5.6 mmol/L glucose. High glucose activated the serine 270 phosphorylation of IRS correlates with JNK phosphorylation in INS-1 cells. Using Western blotting analysis, the levels of JNK phosphorylation were 3.33 fold increased and serine 270 phosphorylation of IRS was 1.17 fold increased in 33.3 G group compared to 11.2 G group (P<0.01). IGF-1 treatment inhibited phosphorylation of JNK and IRS. SP600125 treatment completely blocked JNK phosphorylation in 11.2 G group and reduced JNK phosphorylation by 90% in 33.3 G group. In addition, SP600125 treatment partly reduced serine 270 phosphorylation of IRS by 88.3% in 11.2 G group and 80% in 33.3 G group, the viability of INS-1 cells increased and the apoptosis decreased.CONCLUSION: The toxicity of chronic high glucose, which inhibits the cells viability and induces the cell apoptosis, might be related to suppress IRS signal by activating the JNK pathway. Blocking the JNK pathway might relieve the effect of glucose toxicity to the β cell function by improving the IRS signal pathway.     

circRNA-42398 inhibits activation of hepatic stellate cells via TGF-?β1/Smads signaling pathway modulation

AIM To study the effect of mouse circular RNA-42398 (mmu_circ_42398) over-expression on the activation of hepatic stellate cells. METHODS Mouse hepatic stellate JS1 cells were cultured and randomly divided into control group, vector group and mmu_circ_42398 over-expression group.mmu_circ_42398 over-expression plasmid vector was constructed, and then transiently transfected into JS1 cells using Lipofectamine 2000. The cells were collected 48 h after transfection. Expression of mmu_circ_42398 was detected by RT-qPCR.The backsplice site of PCR products was verified by sequencing. The protein levels of α-smooth muscle actin (α-SMA), collagen type I （Col I), transforming growth factor β1(TGF-β1), Smad2, Smad3, p-Smad2 and p-Smad3 in the cells were determined by Western blot. RESULTS RT-qPCR results showed that the expression of mmu_circ_42398 was significantly increased after mmu_circ_42398 over-expression vector was transiently transfected into the JS1 cells (P<0.01). The protein expression levels of α-SMA and Col I were significantly decreased(P<0.01), and the phosphorylation levels of Smad2 and Smad3 were decreased significantly in mmu_circ_42398 over expression group (P<0.01). However, the protein expression levels of TGF-β1, Smad2 and Smad3 had no significant change (P>0.05). CONCLUSION mmu-circ-42398 inhibits the activation of hepatic stellate cells via TGF-β1/Smads signaling pathway modulation.     

Angiotensin II-induced matrix metalloproteinase-9 expression mediated by NF-κB pathway in human THP-1 cells

AIM: The present study was undertaken to investigate the effect of angiotensin II (AngⅡ) on expression of MMP-9 in THP-1 macrophages. METHODS: Macrophages converted from THP-1 monocytes by incubating with PMA (0.1 μmol/L) for 48 h were divided into PMA group; PMA+AngⅡ group (10-7mol/L, 1 h); PMA+AngⅡ+PDTC group (10 μmol/L, 30 min) and PDTC group. Western blotting was used to detect the MMP-9 and phosphorylation of NF-κB p65, and the expression of MMP-9 mRNA in THP-1 macrophages was measured by RT-PCR.RESULTS: Compared to control group, the expression of MMP-9 (1.06±0.11, P<0.05) and phosphorylation of NF-κB p65 (1.02±0.10, P<0.05) in THP-1 macrophages were expressed when treated with AngⅡ (10-7mol/L); and the expression of MMP-9 mRNA were upregulated (1.22±0.08, P<0.05). However, NF-κB inhibitor PDTC reduced the NF-κB p65 (0.99±0.12, P<0.01) and MMP-9 (1.04±0.14, P<0.01) expressions and decreased the expression of MMP-9 mRNA (0.90±0.06,P<0.01). CONCLUSION: NF-κB signaling pathway contributes to the expression of MMP-9 in THP-1 macrophage induced by AngⅡ.     

Lysophosphatidic acid (LPA) induces the proliferation of astrocytes in rat via pathway of protein kinase C-α and calcium ion in vitro

AIM: To determine if lysophosphatidic acid (LPA) regulates the proliferation of astrocytes (AS) and to approach the mechanism of the process.METHODS: The cerebral AS of the neonatal SD rats were cultured in vitro and divided randomly into control group, PKC excitomotor (PMA) group, LPA group, PKC-α inhibitor (Ro31-8220) group, Ro31-8220+PMA group and Ro31-8220+LPA group. The proliferation of the cells was detected by MTT assay and flow cytometry (FCM). The concentration of intra-cellular calcium ion of the cells (［Ca2＋］i) which were labeled with Fura-2/AM was determined by ultraviolet spectrophotometer. The change of PKC-α inside the cells was observed by Western blotting.RESULTS: LPA and PMA stimulated the proliferation of AS, they also enhanced the expression of PKC-α and increased the concentration of ［Ca2＋］i. After pretreated with Ro31-8220, the abilities of LPA that mentioned above were decreased. The change of ［Ca2＋］i was associated with the diversity of PKC-α.CONCLUSION: LPA promotes the proliferation of AS via the way of PKC-α and Ca2＋.     

Metformin attenuates nerve injury in stroke rats by regulating SIRT1/PGC-1α signaling pathway via miR-29c

AIM To explore the inhibitory effect of metformin （MET） on nerve injury in rats with stroke and its mechanism. METHODS SD rats were randomly divided into sham group （n=15）, model group （n=30）, MET group （n=30）, MET+agomir-NC group （n=30） and MET+agomir group （n=30）. The modified Puisinelli four-vessel occlusion method was used to prepare the model of global ischemic stroke, while the blood vessels in sham rats were isolated without clamping the common artery. One week before modeling, the rats in MET group, MET+agomir-NC group and MET+agomir group were given intraperitoneal injection of 100 mg·kg^-1·d^-1 MET, 100 mg·kg^-1·d^-1 MET+40 nmol/d agomir-NC, 100 mg·kg^-1·d^-1 MET+40 nmol/d miR-29c agomir, respectively, and the rats in sham group and model group were given intraperitoneal injection of the same amount of normal saline. Each treatment in the above groups was given once a day, 0.2 mL each time, for 7 consecutive days. The neurological deficit scores were measured 24, 48 and 72 h after operation. HE staining was used to observe the morphological changes of the hippocampus, and the living neurons were counted. RT-qPCR was used to detect the expression level of miR-29c, and the mRNA levels of silent information regulator 1 （SIRT1） and peroxisome proliferator-activated receptor γ coactivator 1α （PGC-1α） in hippocampus. The protein expression levels of SIRT1 and PGC-1α were determined by Western blot. RESULTS At the same time point, compared with model group, the neurological deficit score in MET group was significantly decreased, and the survival rate of the neurons was significantly increased （P<0.05）. Compared with MET+agomir-NC group, the neurological deficit score in MET+agomir group was increased, and the survival rate of the neurons was significantly decreased （P<0.05）. With the prolongation of time, except for sham group, the neurological deficit score was increased and the survival rate of the neurons was decreased. At 72 h after operation, compared with sham group, the expression of miR-29c in hippocampus of model group was significantly increased, and the mRNA and protein expression levels of SIRT1 and PGC-1α were significantly decreased （P<0.05）. Compared with model group, the expression of miR-29c in hippocampus of MET group was significantly decreased, and the expression of SIRT1 and PGC-1α at mRNA and protein levels was significantly increased （P< 0.05）. Compared with MET+agomir-NC group, the expression of miR-29c in hippocampus of MET+agomir group was significantly increased, and the mRNA and protein expression of SIRT1 and PGC-1α was significantly decreased （P<0.05）. CONCLUSIONS MET alleviates nerve injury in stroke rats, which may be related to down-regulation of miR-29c and promotion of SIRT1/PGC-1α signaling pathway activation.     

Effects of platelet-rich plasma on chondrocyte apoptosis and NLRP3/IL-1β signaling pathway in rabbits with osteoarthritis

AIM To explore the effect of platelet-rich plasma (PRP) on rabbit osteoarthritis and its possible mechanism. METHODS The rabbits with knee osteoarthritis were prepared and then divided into model group, sodium hyaluronate (SH) group and PRP group, and another sham operation group was set up, with 6 rabbits in each group. The gross morphological changes of rabbit cartilage were observed. HE staining was used to evaluate the pathomorphological changes of the cartilage. TUNEL staining was used to detect the apoptosis of chondrocytes. The expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1β （IL-1β） signaling pathway-related molecules was observed by immunohistochemical staining, and the protein levels of caspase-3, Bcl-2 and Bax were determined by Western blot. Chondrocytes were isolated and processed according to grouping, and the NLRP3 and IL-1β levels of the cells were measured by ELISA. RESULTS Compared with sham operation group, Pelletier score, Mankin score, chondrocyte apoptotic rate, the positive protein expression rates of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in model group were increased significantly (P<0.05), while the protein expression of Bcl-2 was decreased significantly (P<0.05). Compared with model group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in SH group and PRP group were decreased significantly (P<0.05), while the protein expression of Bcl-2 was increased significantly (P<0.05). In PRP group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax were lower than those in SH group, while the protein expression of Bcl-2 was higher than that in SH group (P<0.05). Compared with control group, the expression of NL?RP3 and IL-1β in MCC950 (NLRP3 ihibitor) group were significantly reduced (P<0.05), the expression of NLRP3 in eucalyptol (IL-1β inhibitor) group was not significantly changed (P>0.05), and the expression of IL-1β was significantly reduced (P<0.05). CONCLUSION Platelet-rich plasma promotes the repair of cartilage in osteoarthritis rabbits, which has better effect than SH. The mechanism may be related to the inhibition of NLRP3/IL-1β pathway and the reduction of chondrocyte apoptosis.     

PPARγ affects epithelial-mesenchymal transition in renal tubular epithelial cells under high glucose by regulating AKT/FAK signaling pathway through PTEN

AIM To investigate the role of peroxisome proliferator-activited receptor γ （PPARγ） in the regulation of PTEN/AKT/FAK signaling pathway and epithelial-mesenchymal transition （EMT） in renal tubular epithelial cells grown in high-glucose environment. METHODS Renal tubular epithelial cells （NRK52E cells） cultured in high glucose were used as an in vitro model system. PPARγ was over-expressed or knocked down in these cells, and its effect on PTEN expression was determined by RT-qPCR, immunofluorescence and Western blot. The changes of EMT-related proteins were also measured. The PPARγ inhibitor GW9662 and the PPARγ agonist rosiglitazone were used along with PTEN over-expression or knockdown to determine whether the effects of PPARγ were mediated through PTEN. RESULTS PPARγ over-expression resulted in the increased expression of PTEN at mRNA and protein levels, the up-regulation of E-cadherin, and the down-regulation of vimentin and α-SMA. Knockdown of PPARγ expression reduced the mRNA and protein levels of PTEN, down-regulated E-cadherin, and up-regulated vimentin and α-SMA （P<0.05）. Treatment of the NRK-52E cells with GW9662 decreased PTEN expression and increased the protein levels of p-AKT （Thr308）, FAK and p-FAK （Tyr397）. These effects were rescued by PTEN over-expression. Treatment of the NRK-52E cells with rosiglitazone increased PTEN expression and decreased the protein levels of p-AKT （Thr308）, FAK and p-FAK （Tyr397）. These effects were rescued by PTEN knockdown. These changes were all statistically significant （P<0.05）. CONCLUSION PPARγ regulates the mRNA and protein expression of PTEN in renal tubular epithelial NRK52E cells, and affects EMT in renal tubular epithelial cells. The regulation of AKT/FAK signaling pathway by PPARγ is primarily mediated by PTEN.     

Urotensin Ⅱinduces pulmonary arterial smooth muscle cell proliferation and up-regulates Egr-1 expression through ERK1/2 pathway in rats

AIM: To investigate the effect of urotensinⅡ (UⅡ) on the proliferation of cultured rat pulmonary arterial smooth muscle cells (PASMCs), and to explore whether mitogen-activated protein kinase (MAPK) signaling pathways and early growth response factor-1 (Egr-1) involved in the regulation of the PASMCs proliferation stimulated by UⅡ. METHODS: The rat PASMCs were isolated and cultured in vitrowith explant culture technique. The proliferation of cultured PASMCs stimulated by different doses of UⅡwas detected by BrdU incorporation. The mRNA expression of extracellular signal-regulated kinase 1/2 (ERK1/2), stress-activated protein kinase (SAPK), p38 MAPK and Egr-1 in cultured PASMCs treated with UⅡ, UⅡ-specific antagonist urantide, and ERK1/2 inhibitor PD98059 was detected by real-time PCR. The protein levels of phosphorylated ERK1/2 (p-ERK1/2), p-SAPK, p-p38 and Egr-1 in cultured PASMCs were determined by Western blotting. RESULTS: UⅡ at concentrations of 1 μmol/L, 0.1 μmol/L and 0.01 μmol/L increased the proliferation of cultured PASMCs in a dose-dependent manner (P<0.01 or P<0.05), with the maximal effect at a concentration of 1 μmol/L. However, urantide inhibited the promotion effect of UⅡ on PASMC proliferation (P<0.05). UⅡ up-regulated the mRNA expression of ERK1/2, SAPK and Egr-1 (P<0.01 or P<0.05), but not the p38 MAPK. However, the up-regulatory effect of UⅡ on ERK1/2 and Egr-1 expression was inhibited by PD98059 and/or urantide (P<0.01 or P<0.05). UⅡ also increased the protein levels of p-ERK1/2, p-SAPK and Egr-1 (P<0.01 or P<0.05), but the promotion effect was also inhibited by PD98059 and/or urantide (P<0.01 or P<0.05).CONCLUSION: UⅡ increases the proliferation of PASMCs, and U Ⅱand Egr-1 participates in UⅡ-mediated proliferation of cultured PASMCs through activation of ERK1/2 signal pathway.     

Regulatory effect of NOX-4 on PI3K signaling pathway in TGF-β1-induced collagenⅠsynthesis from lung cancer cells

AIM: To investigate the regulatory effect of NADPH oxidase-4 (NOX-4) on PI3K signaling pathway in transforming growth factor-β1 (TGF-β1)-induced collagen type I (collagen I)synthesis from lung cancer cells and the mechanisms. METHODS: Human lung cancer A549 cells were cultured in vitro and stimulated with TGF-β1. The expression of NOX family and collagen family at mRNA and protein levels as well as the PI3K class I catalytic subunits and the activation of PI3K signaling pathway was measured. A549 cells were pre-treated with NOX-4 inhibitor diphenyleneiodonium (DPI), and the expression of collagen I at mRNA level as well as the PI3K class I catalytic subunits and the activation of PI3K signaling pathway was measured upon TGF-β1 stimulation. RESULTS: TGF-β1 stimulated the expression of NOX-4 and collagen I at mRNA and protein levels as well as the expression of PIK3CD and the activation of PI3K signaling pathway at a dose-and time-dependent manner. NOX-4 inhibitor DPI partly reversed TGF-β1-induced collagen I expression. Inhibition of NOX-4 down-regulated the degree of TGF-β1-stimulated activation of PI3K signaling pathway without effect on the expression of PIK3CD. CONCLUSION: NOX-4 participates in TGF-β1-induced collagenⅠsynthesis from lung cancer cells via regulating the activation of PI3K signaling pathway. TGF-β1/NOX-4/PI3K signaling pathway axis acts as a regulatory role in collagenⅠsynthesis from lung cancer cells.     

Effects of Huanglian-jiedu decoction on TLR4/NF-κB signaling pathway and goblet cells of mucosa in rats with allergic rhinitis

AIM To investigate the effect of Huanglian-jiedu decoction （HLJD） on goblet cells and Toll-like receptor 4 （TLR4）/nuclear factor （NF）-κB signaling pathway in allergic rhinitis rats. METHODS The rat model of allergic rhinitis was made by ovalbumin. The model rats were divided into model group, low-, medium- and high-dose HLJD groups, and positive control drug group. The rats in low-, medium- and high-dose HLJD groups were given different doses（5, 10 and 20 g/kg, respectively） of crude drug by intragastric administration, the rats in positive control group was given fluticasone propionate nasal spray （50 μg per side）, and the rats in control group and model group were given normal saline, once per day for 10 days. The behaviors were observed and scored after modeling and treatment, the weight of nasal secretion was measured after the treatment. The goblet cells in nasal mucosa were observed by periodic acid-Schiff （PAS） staining. The morphological changes of nasal mucosa were observed by hematoxylin-eosin （HE） staining. The interleukin （IL）-4 and IL-5 levels in nasal mucosa were measured by ELISA. The mRNA levels of mouse calcium-activated chloride channel 3 （mCLCA3） and mucin 5AC （MUC5AC） were detected by RT-qPCR. The protein expression of TLR4 and NF-κB p65 was determined by Western blot. RESULTS After modeling, compared with control group, the behavioral scores in model group, low-, medium- and high-dose HLJD groups and positive control group were increased （P<0.05）. The eosinophils, neutrophils and lymphocytes in nasal mucosa were seriously infiltrated, inflammatory infiltration was obvious, and obvious small vessel dilatation and interstitial edema in model group were observed. With the increase in the dosage of HLJD, the lymphatic infiltration was obviously relieved, but the eosinophil and neutrophil infiltration still existed, and the inflammatory infiltration was relieved. Compared with control group, the behavioral score, nasal secretion, the relative proportion of goblet cells in the mucosa, the IL-4 and IL-5 levels, the mRNA levels of mCLCA3 and MUC5AC, and the protein expression of TLR4 and NF-κB p65 in the mucosa of model group were increased （P<0.05）. Compared with model group, the behavioral score, nasal secretion, the relative proportion of goblet cells in the mucosa, the IL-4 and IL-5 levels, the mRNA levels of mCLCA3 and MUC5AC, and the protein expression of TLR4 in the mucosa of low-, medium- and high-dose HLJD groups and positive control group were increased （P<0.05）, and the protein expression of NF-κB p65 in the mucosa of medium- and high-dose HLJD groups and positive control group was decreased （P<0.05）. CONCLUSION Huanglian-jiedu decoction reduces the relative proportion of goblet cells in the nasal mucosa of rats with allergic rhinitis, which may be achieved by inhibiting TLR4/NF-κB signaling pathway.