张力刺激对关节软骨细胞β-肌动蛋白mRNA表达的影响

目的 观察张力刺激对关节软骨细胞β-肌动蛋白(β-aetin)mRNA表达的影响.方法 分别获取正常和骨关节炎关节软骨细胞,给予3%、6%和15%的张力刺激,运用实时定量PCR方法检测不同张力刺激强度下关节软骨细胞β-actin mRNA表达的变化.结果 6%和15%的张力刺激均可明显提高lE常关节软骨细胞β-actinmRNA表达(1.34±0.05,1.36±0.04,P＜0.05),而只有15%的张力刺激才能明显增加骨关节炎关节软骨细胞β-actin mRNA表达.结论 关节软骨细胞β-actin mRNA表达量随张力刺激强度不同而变化,不同内外环境使关节软骨细胞对张力刺激的反应不同,故在其相关生物力学研究中不能应用β-actin作为内参.     

Inhibition of histone deacetylases antagonized FGF2 and IL-1β effects on MMP expression in human articular chondrocytes

Fibroblast growth factor-2 (FGF2) and interleukin-1β (IL-1β) stimulate the expression of matrix metalloproteinases (MMPs) in articular chondrocytes, which may contribute to cartilage degradation and development of osteoarthritis. Histone deacetylases (HDACs) have recently been implicated in the regulation of MMP gene expression. To investigate the functional involvement of HDACs in the signaling pathway of FGF2 and IL-1β, we examined the effects of HDAC inhibition on activities of FGF2 or IL-1β on gene expression of MMP-1, MMP-3, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS5), collagen type II, and aggrecan. Human articular chondrocyte cultures were treated with FGF2 or IL-1β in the presence or absence of HDAC inhibitor (trichostatin A, TSA). Gene expression levels after treatments were assessed using quantitative real time PCR. Results showed that FGF2 and IL-1β both increased MMP-1 and -13 expression, while IL-1β also increased MMP-3 mRNA levels. These effects were attenuated in the presence of TSA in a dose dependent manner. In contrast to the effects on MMPs, FGF2 decreased mRNA levels of ADAMTS-5, which was not affected by HDAC inhibition. FGF2, IL-1β, and TSA inhibited expression of aggrecan, while TSA also decreased mRNA levels of collagen type II. These findings showed that HDAC inhibition antagonized FGF2 and IL-1β induced MMP expression. Combination of FGF2 and the HDAC inhibitor decreases both anabolic and catabolic genes, which may slow the cartilage turnover and be beneficial for maintaining cartilage integrity.     

Effects of transforming growth factor-β2 on myocilin expression and secretion in human primary cultured trabecular meshwork cells

High intraocular pressure (IOP) is a risk factor for primary open-angle glaucoma (POAG). The trabecular meshwork (TM), a reticular tissue in the outflow passage of the aqueous humor (AH), is a major contributor to intraocular outflow resistance. High levels of myocilin (MYOC), which is expressed in the TM, are associated with high IOP. Furthermore, transforming growth factor-β2 (TGF-β2) concentrations in human AH are significantly elevated in POAG patients. This study was designed to investigate the effects of TGF-β2 on MYOC expression and secretion in human primary cultured TM cells. Primary cultured human TM cells were treated with 0 (control group), 1, 10, and 100 ng/mL TGF-β2 for 12, 24, or 48 h. MYOC mRNA and protein expressions in TM cells and protein secretion in conditioned media were analyzed by semi-quantitative RT-PCR, Western blotting, and enzyme-linked immunosorbent assays (ELISA), respectively. TM cells treated with 1, 10, and, 100 ng/mL TGF-β2 for 48 h showed higher MYOC mRNA and protein expressions than those in the control group (0 ng/mL TGF-β2) (all P < 0.05). Treatment with TGF-β2 for 48 h also induced MYOC secretion in conditioned media in a dose-dependent manner (0 ng/mL: 7.107±1.163 pg/ml; 1 ng/mL: 7.879±1.894 pg/ml; 10 ng/mL: 8.063±1.181 pg/ml; 100 ng/mL: 8.902±0.699 pg/ml; all P < 0.05). In Conclusion, TGF-β2 induced MYOC expression and secretion in human primary cultured TM cells. Further investigations are required to confirm the involvement of these two factors in POAG pathogenesis.     

Change of inflammatory cytokines after co-culture of inflamed cartilage blocks and chondrocytes transfected by interleukin-β1 receptor antagonist gene and transforming growth factor-β1 gene in vitro

Objective To evaluate the in vitro effects of recombinant human interluekin-β1 receptor antagonist(IL-1Ra) gene and transforming growth factor-β1 (TGF-β1) gene on rabbit osteoarthritis (OA).Methods Articular cartilages were extracted from mature New Zealand rabbits and by enzyme digestion,isolated for chondrocytes which were then identified with specific extracellular matrix collagen type Ⅱ stained immunocytochemistry.The chondrocytes were divided into IL-1Ra-transfected group (group A), TGF-β1?transfected group (group B) , combined IL-1Ra- and TGF-β1-transfected group (group C) , untransfected group (group D) and the blank control group (group E).LipofectamineTM 2000 Reagent was used as the vehicle for transfection among groups A, B and C.All the groups of chondrocytes were co-cultured with fragmented articular cartilages and added with 20 ng IL-β 1?expect for group E.The transgenic expression of chondrocytes was detected under fluorescence microscope at 12h,24h,2d,4d and 6 d after transfection and co-culture.In addition, radioimmunoassay (RIA) was used to determine the levels of IL-1βand TNF-α in each group at 2 d, 4 d and 6 d after transfection and co-culture.Results The chondrocytes were successfully isolated and cultured.Collagen type Ⅱ stained immunocytochemistry showed the brownish - yellow cytoplasm and unstained chromophobic nuclei.Under fluorescence microscope, the expression of enhanced green fluorescent protein was observed in groups A, BandC, which peaked at 24 hours after transfection (16.16±2.71)% vs (16.54±2.91)% vs (17.20±2.39)% and gradually declined 2 d later.At any time spots, the IL-1βevel was highest in group D, followed by group B, group A, group C, and group E.The level of TNF-a in each group was ordered by group D＞group A＞group B＞group C＞group E on days 2 and 6, and by group E＞group A＞group B＞group C＞group D on day 4.The level of TNF-α in group A was slightly higher than that of group B, but the difference was not statistical significance.There were statistical difference among the other groups.The expressions of IL-1βand TNF-α in groups A, B and C were significantly lower on day 6 than those on days 2 and 4.The level of IL-1βin groups D and E did not change with time, while the level of TNF -α was the lowest in group D and highest in group E on day 4.ConclusionsTransfection with IL-1Ra or TGF-β1 can reduce the level of inflammatory cytokines.Combined use of IL-1Ra and TGF-β1 genes may show control of inflammatory response and provide evidences for gene therapy of osteoarthritis.     

Effects and relationship of ERK1 and ERK2 in interleukin-1β-induced alterations in MMP3, MMP13, type II collagen and aggrecan expression in human chondrocytes

Interleukin (IL)-1β plays an important role in the pathogenesis of osteoarthritis and catabolic processes in articular cartilage. Growing evidence suggests that ERK1/2 activation is involved in IL-1β-mediated matrix metalloproteinase (MMP) 3, MMP13, type?II collagen and aggrecan expression in chondrocytes. To investigate the respective effects and the relationship of ERK1 and ERK2, knockdown of ERK1 and/or ERK2 was performed in human chondrocytes using specific small interfering RNAs (siRNAs), and the cells were treated with IL-1β (10?ng/ml) for 24?h. Uninfected chondrocytes treated with IL-1β (10?ng/ml) were used as a positive control. Other cells cultured without IL-1β or siRNA treatment were used as a negative control. The mRNA levels of MMP3, MMP13, type?II collagen and aggrecan were evaluated by quantitative real-time PCR. The protein levels of MMP3 and MMP13 in the culture medium were examined by ELISA. The protein levels of type?II collagen, aggrecan, ERK1/2 and phospho-ERK1/2 were evaluated by western blotting. The results indicate that IL-1β enhances MMP3 and MMP13 expression and inhibits type?II collagen and aggrecan expression. Activation of the MAPK/ERK pathway was observed. Knockdown of ERK1 or ERK2 significantly reversed these effects to similar degree. Combined knockdown of ERK1 and ERK2 displayed synergistic effects. ERK1 and phospho-ERK1 or ERK2 and phospho-ERK2 were inhibited by knockdown of ERK1 or ERK2, respectively. No compensatory effect by up-regulation of the opposite isoform was observed. The combined knockdown suppressed ERK1/2 and phospho-ERK1/2. The data suggest that although inhibition of both ERK1 and ERK2 is more effective, inhibition of either ERK isoform may be sufficient and could be used for novel therapies or as drug targets for pharmacological intervention in cartilage breakdown in osteoarthritis.     

Effects of antipsychotic drugs on BDNF,GSK-3β, and β-catenin expression in rats subjected to immobilization stress

Brain-derived neurotrophic factor (BDNF), glycogen synthase kinase-3β (GSK-3β), and β-catenin have been reported to be altered in patients with schizophrenia and have been targeted by antipsychotic drugs. Atypical antipsychotics, but not typical antipsychotics, exert neuroprotective effects by regulating these proteins. In this study, we analyzed the effects of the atypical antipsychotic drugs olanzapine and aripiprazole and a typical antipsychotic drug, haloperidol, on the expression of BDNF, phosphorylated GSK-3β, and β-catenin in the hippocampus of rats subjected to immobilization stress. Rats were subjected to immobilization stress 6 h/day for 3 weeks. The effects of olanzapine (2 mg/kg), aripiprazole (1.5 mg/kg), and haloperidol (1.0 mg/kg) were determined on BDNF, serine⁹-phosphorylated GSK-3β, and β-catenin expression by Western blotting. Immobilization stress significantly decreased the expression of BDNF, phosphorylated GSK-3β, and β-catenin in the hippocampus. Chronic administration of olanzapine and aripiprazole significantly attenuated the decreased expression of these proteins in the hippocampus of rats caused by immobilization stress, and significantly increased the levels of these proteins even without the immobilization stress. However, chronic haloperidol had no such effect. These results suggest that olanzapine and aripiprazole may exert beneficial effects by upregulating BDNF, phosphorylated GSK-3β, and β-catenin in patients with schizophrenia.     

Effects of antipsychotic drugs on BDNF, GSK-3β, and β-catenin expression in rats subjected to immobilization stress

Brain-derived neurotrophic factor (BDNF), glycogen synthase kinase-3β (GSK-3β), and β-catenin have been reported to be altered in patients with schizophrenia and have been targeted by antipsychotic drugs. Atypical antipsychotics, but not typical antipsychotics, exert neuroprotective effects by regulating these proteins. In this study, we analyzed the effects of the atypical antipsychotic drugs olanzapine and aripiprazole and a typical antipsychotic drug, haloperidol, on the expression of BDNF, phosphorylated GSK-3β, and β-catenin in the hippocampus of rats subjected to immobilization stress. Rats were subjected to immobilization stress 6 h/day for 3 weeks. The effects of olanzapine (2 mg/kg), aripiprazole (1.5 mg/kg), and haloperidol (1.0 mg/kg) were determined on BDNF, serine⁹-phosphorylated GSK-3β, and β-catenin expression by Western blotting. Immobilization stress significantly decreased the expression of BDNF, phosphorylated GSK-3β, and β-catenin in the hippocampus. Chronic administration of olanzapine and aripiprazole significantly attenuated the decreased expression of these proteins in the hippocampus of rats caused by immobilization stress, and significantly increased the levels of these proteins even without the immobilization stress. However, chronic haloperidol had no such effect. These results suggest that olanzapine and aripiprazole may exert beneficial effects by upregulating BDNF, phosphorylated GSK-3β, and β-catenin in patients with schizophrenia.     

Effects of serum containing wuzang wenyang huayu decoction on phosphorylated-tau protein expression in alzheimer’s disease cell model北大核心

BACKGROUND: Various previous studies have shown that Wuzang Wenyang Huayu Decoction has a good therapeutic effect on Alzheimer’s disease, but its pharmacological mechanism has not been fully elucidated. OBJECTIVE: To investigate the effect of Wuzang Wenyang Huayu Decoction drug-containing serum on the expression of peroxisome proliferator-activated receptor γ and phosphorylated-tau protein in Alzheimer’s disease cell model. METHODS: Beta amyloid protein was used to induce primary hippocampal neurons to establish the currently recognized Alzheimer’s disease cell model. Wuzang Wenyang Huayu Decoction drug-containing serum and donepezil hydrochloride drug-containing serum were given for intervention for 72 hours. The dendritic length and branch number of primary neurons cells were detected by immunofluorescence assay. The expression levels of peroxisome proliferator-activated receptor γ and phosphorylated-tau protein were detected by western blot assay. RESULTS AND CONCLUSION: Compared with the control group, the length and branch number of dendritic cells in the model group were significantly decreased (P < 0.05), peroxisome proliferator-activated receptor γ expression decreased, and phosphorylated-tau protein increased (P < 0. 05 or P < 0. 01). Compared with the model group, the dendritic length and branch number of neurons in Wuzang Wenyang Huayu group and donepezil hydrochloride group increased, the expression of PPARγ increased, and the expression of phosphorylated-tau protein significantly decreased (P < 0. 05 or P < 0. 01). Results confirmed that Wuzang Wenyang Huayu Decoction has neuroprotective effect on Alzheimer’s disease cells induced by beta amyloid protein, and its mechanism may be related to upregulation of peroxisome proliferator-activated receptor γ protein and inhibition of phosphorylated-tau protein. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

Effect of PKC signalling pathway and aldose reductase on expression of fibronectin induced by transforming growth factor-β1 in human mesangial cells

Objective To study the effect of PKC signalling pathway and aldose reductase (AR) on the expression of fibronectin (FN) induced by transforming growth factor-β1 (TGF-β1). Methods Human mesangial cells (HMCs) were cultured and transfected with pcDNA3-AR, and subject to AR gene silencing with small interfering RNA (siRNA) and then the cell was treated with recombinant human TGF-β1. The AR mRNA expression in the HMCs was examined using real time RT-PCR and protein expression of AR and FN was detected by Western blotting. Results The cultured HMC treated with TGF-$l showed increased expression of AR and FN,the normal HMC showed not reduced expression of FN after incubation with single inhibitors of AR. Pre-incubation of cells with inhibitors of AR and PKC, then the different groups of cells were treated with TGF-$l ,and the induction effect on FN expression was suppressed (34%) in HMC. HMCs transfected with AR showed a strong protein expression of FN, which was increased by 3. 6-fold after treatment with TGF-pl (P <0. 05) , and the induction effect on FN expression was suppressed by G(O)6983 (42%) in HMCs (P < 0. 05) . The HMC with AR gene knock-down by siRNA showed a decreased expression of AR and 90% decrease of FN protein in HMCs(P <0. 01) , and TGF-β1-induced up-regulation of FN was significantly suppressed by siRNA (12%) in HMCs (P <0. 01). Conclusions AR is capable of regulating FN expression only in the presence of TGF-β1, and this reaction is possibly accomplished through the activation of PKC signalling pathway.     

Effect of PKC signalling pathway and aldose reductase on expression of fibronectin induced by transforming growth factor-β1 in human mesangial cells

Objective To study the effect of PKC signalling pathway and aldose reductase (AR) on the expression of fibronectin (FN) induced by transforming growth factor-β1 (TGF-β1). Methods Human mesangial cells (HMCs) were cultured and transfected with pcDNA3-AR, and subject to AR gene silencing with small interfering RNA (siRNA) and then the cell was treated with recombinant human TGF-β1. The AR mRNA expression in the HMCs was examined using real time RT-PCR and protein expression of AR and FN was detected by Western blotting. Results The cultured HMC treated with TGF-$l showed increased expression of AR and FN,the normal HMC showed not reduced expression of FN after incubation with single inhibitors of AR. Pre-incubation of cells with inhibitors of AR and PKC, then the different groups of cells were treated with TGF-$l ,and the induction effect on FN expression was suppressed (34%) in HMC. HMCs transfected with AR showed a strong protein expression of FN, which was increased by 3. 6-fold after treatment with TGF-pl (P <0. 05) , and the induction effect on FN expression was suppressed by G(O)6983 (42%) in HMCs (P < 0. 05) . The HMC with AR gene knock-down by siRNA showed a decreased expression of AR and 90% decrease of FN protein in HMCs(P <0. 01) , and TGF-β1-induced up-regulation of FN was significantly suppressed by siRNA (12%) in HMCs (P <0. 01). Conclusions AR is capable of regulating FN expression only in the presence of TGF-β1, and this reaction is possibly accomplished through the activation of PKC signalling pathway.     

Effects of the Overall Alkaloid of a Traditional Chinese Medicine “Tongbiling” on the Cytokine Expression in Thl and Th2 Cells of Rheumatoid Arthritis and Their Signaling Pathway

To investigate the effects of overall alkali of a traditional Chinese medicine “Tongbiling” (brucine and strychnine alkaloids in main) on the cytokines expression in Th1 and Th2 cells in the synovial fluid of patients with rheumatism arthritis and their signal pathway, the mononuclear cells in the synovial fluid (SFMC) of patients were isolated by Ficoll-Hypaque gradient centrifugation, and the CD3^+ CD69^+ and CD3^+ HLA-DR antigen were analyzed by flow cytometry in comparison with those of the peripheral blood. The rest of cells were cultured after resuspension with RPMI 1640 culture medium. Phorbol 12, 13-dibutyrate (PDB) and ionomycin were added successively into the culture with various concentration of overall alkali Tongbiling (TBL). After 4 h of cultivation, the expression of IFN-γ and IL-4 in CD3^+ cells were analyzed by flow cytometry. The influence of overall alkali TBL ( 100 mg/I,) on the intracellular calcium was investigated after Fluo-3/AM labeling and stimulation with PDB and ionomycin at 1, 2, 4 and 10 min, and the influence of TBL on the expression of CD3^+ CD69^+ cells were determined with stimulation of PDB for 24 h in the whole blood lymphocytes culture. It was found that the percentage of T cells bearing CD69 was significantly up-regulated (77%), while that of T cells bearing HLA-DR was 44% in the synovial mononucleated cells. After PDB and ionomycin stimulation, the expression of IFN-7 in CD3 ~ cells were up-regulated, but there was no change on the expression of IL-4 in CD3^+ cells, indicating that ratio of Th1/Th2 was significantly increased and Th cells differentiate to Thl cells in mainly. Four concentrations of overall alkaloid of TBI, (200 mg/L, 100 mg/L, 50 mg/L, 25 mg/L) could down-regulated the expression of IFN-γ in CD3^+ cells and the Th1/Th2 ratio obviously, but all the concentrations of the overall alkaloids had no effect on the expression of IL-4 in CD3^+ cells. 100 mg/L concentration of the overall alkaloid did not down-regulate the intracellular calcium level. Each concentration of the overall alkaloid could down-regulated the expression CD69 obviously on the PDB-activated mouse T cells. It concluded from the above observations that the overall alkaloid of TBL could relieve the inflammatory and immune damages by suppressing the expression of Thl type cytokines and Th1 cell differen-tiation, regulating the imbalance of Th1/Th2 cells and inhibiting the early activation of the T lymphocytes bearing CD69. There was no remarkable influence on the intracellular calcium signaling transduction pathway. The inhibitory effected on T cells to express 1FN-γ might be due to the suppression of PKC-MAPK signaling pathway. From the standpoint of traditional Chinese medicine, this might be due to the regulation of “Yin” and “Yang” imbalance of joints to modify the pathological status in rheumatoid arthritis. This study provided an experimental basis for the application of overall alkaloids of TBL in the treatment of rheumatoid arthritis.