Association of TNF-α upregulation of MMP-9 activation in monocyte-derived macrophages with progression of joint damage in patients with rheumatoid arthritis

AIM: To explore the expression and activation of matrix metalloproteinase-9 (MMP-9) from monocyte-derived macrophages induced by tumor necrosis factor-α (TNF-α) and to investigate its association with progression of joint damage in patients with rheumatoid arthritis. METHODS: TNF-α and MMP-9 in serum and synovial fluid from patients with early RA and controls were tested with a double-antibody enzyme-linked immunosorbent assay. The correlation between MMP-9 and Larsen score over the first 12 months was analyzed. THP-1 cells differentiated by the treatment with TPA were stimulated with increasing concentration of TNF-α for 24 h in vitro. The protein expression of MMP-9 was determined by Western blotting. The activity of MMP-9 was measured by gelatinolytic zymography. Boyden chamber-matrigel in vitro invasion assay was used to detect the invasive capacity. RESULTS: The levels of TNF-α and MMP-9 in serum and synovial fluid of RA patients were significantly higher than those in controls (P<0.05). Serum and synovial fluid levels of MMP-9 correlated significantly with Larsen score (r=0.37 and 0.32, P<0.01). The MMP-9 activity and invasive ability of co-cultured THP-1 cells with TNF-α and TPA were higher than those of non-TNF-α treatment. CONCLUSION: TNF-α upregulates MMP-9 activation and promotes infiltration of monocyte-derived macrophages, indicating that TNF-α play an important role in the pathogenesis of RA.     

Effects of diosmin on changes of TNF-α, IL-1β, IL-6, IL-8 and IL-10 in serum and kidney tissues of rats with kidney ischemia and reperfusion

AIM: To observe the effects of diosmin on the production of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), IL-6, IL-8 and IL-10 in serum and kidney tissues of rats with kidney ischemia and reperfusion (I/R). METHODS: Sprague-Dawley rats (180 in total) were randomly divided into 3 groups including sham operation group (sham),I/R group and diosmin+I/R group (diosmin+I/R). At the end of the experiment, the blood and kidney tissues were obtained and TNF-α, IL-1β, IL-6, IL-8 and IL-10 were detected by ELISA. RESULTS: The levels of TNF-α, IL-1β, IL-6, IL-8 and IL-10 in serum and kidney tissues in I/R group and diosmin+I/R group were significantly higher than those in sham group (P<0.01 or P<0.05). Following the development of the pathologic process, the level of TNF-α, IL-1β, IL-6 and IL-8 was significantly increased in I/R group and diosmin+I/R groups, but the level of IL-10 was significantly decreased in I/R group and significantly increased in diosmin+I/R group. The levels of TNF-α, IL-1β, IL-6 and IL-8 in I/R group was significantly higher than those in diosmin+I/R group (except TNF-α at 1 h in diosmin+I/R group). The level of IL-10 in diosmin+I/R group was significantly higher than that in I/R group (P<0.01 or P<0.05). CONCLUSION: Diosmin not only decreases the production of TNF-α, IL-1β, IL-6 and IL-8, but also promotes the production of anti-inflammatory cytokine IL-10, suggesting that the protective effect of diosmin on kidney I/R injury was associated with anti-inflammatory mechanism.     

Association of IFN-γ and IL-4 gene polymorphisms with childhood bronchial asthmatic susceptibility and the levels of plasma IFN-γ,IL-4 and IgE

AIM: To investigate the gene polymorphisms of interferon-γ(IFN-γ) and interleukin-4(IL-4) and the association with asthmatic susceptibility and the levels of plasma IFN-γ, IL-4 and IgE of asthmatic children. METHODS: 100 asthmatic children and 122 control children were enrolled the study. The genotypes of IFN-γ gene-179G/T polymorphism, IL-4 gene-33C/T and-589C/T polymorphisms were tested by PCR-RFLP.The genotype of IFN-γ gene +874A/T polymorphism was tested by AS-PCR.The CA repeat polymorphism of IFN-γ gene was detected by capillary electrophoresis technique.The levels of serum IFN-γ, IL-4 and IgE were measured by ELISA. RESULTS: 100 asthmatic children and 122 control children were all GG homozygotes at -179 locus of IFN-γ gene.-179 locus of IFN-γ gene has no mutation. The genotypes and allele frequency of IFN-γ gene +874A/T and CA repeat polymorphisms showed no significant difference between asthmatic children and the control(P>0.05). An association was revealed between IFN-γ gene +874A/T polymorphism and the level of plasma IFN-γ.The level of IFN-γ was lower in AA genotype than in AT genotype(P<0.05). The genotypes and allele frequency of IL-4 gene -33C/T and -589C/T polymorphisms showed significant difference between asthmatic children and the control(P<0.05).The levels of plasma IL-4 and IgE were higher in TT genotype at -33 locus and -589 locus than those in CT genotype, but only -33C/T polymorphism was associated with the level of plasma IL-4(P<0.05). CONCLUSION: The IFN-γ gene +874A/T and CA repeat polymorphisms were not correlated with asthmatic susceptibility, but there is significant correlation between the level of IFN-γ and +874A/T polymorphism. TT genotype of IL-4 gene -33 locus and -589 locus maybe the susceptible genotype of asthma in children, and the -33 locus polymorphism is associated with the level of IL-4.     

Effect of the acupotome therapy and electro-acupuncture on the serum contents of IL-1β, IL-6 and TNF-α in rabbits with knee osteoarthritis

AIM: IL-1β, IL-6 and TNF-α play important roles in emergence of osteoarthritis. This study aims at observing the effect of the acupotome therapy and electro-acupuncture on the cytokines in serum of rabbits with osteoarthritis. METHODS: 52 New Zealand rabbits were divided randomly into the normal group, model group, acupotome group and electro-acupuncture group. Knee osteoarthritis of the model rabbits was made with the straightened immobilization method. The acupotome and electro-acupuncture therapies were applied for three weeks. One week after the treatment the serum was collected, and the changes of IL-1β, IL-6 and TNF-α in serum were detected with RIA. RESULTS: In comparison with the control group, the contents of IL-1β, IL-6 and TNF-α elevated significantly in the knee osteoarthritis model group (P<0.05). Compared to the knee osteoarthritis model group, the contents of the cytokines in acupotome treatment group and electro-acupuncture treatment group decreased significantly (P<0.05). No significant difference between the content of cytokines in the acupotome treatment or electro-acupuncture treatment groups (P<0.05) was observed, also no statistical difference between the acupotome treatment or electro-cupuncture treatment groups and the control group was found. However, the contents of the three cytokines in the acupotome treatment and electro-acupuncture treatment groups were still higher than those in control group. CONCLUSION: The acupotome and electro-acupuncture treatment can decrease the release of IL-1β, IL-6 and TNF-α, indicating that the two therapies play an important role in improvement of the articular cartilage cell injury and function through inhibiting the generation of matrix protease and alleviation of degradation of the cartilage matrix.     

Effect of IL-1β and IL-6 on expression of nerve growth factor in human nucleus pulposus cells

AIM: To determine the effect of interleukin-1β(IL-1β)and IL-6 on the expression of nerve growth factor (NGF) by human nucleus pulposus (NP) cells. METHODS: The NP cells from the normal disc of operative patients with scoliosis were isolated, cultured and identified. After 7 days preculture, the NP cells were treated with IL-1β (10 μg/L, 50 μg/L) or IL-6 (10 μg/L, 50 μg/L) for 48 h in the experimental groups and 0.3% PBS was used in the control groups. The expression of NGF was detected by the methods of immunohistochemistry, semi-quantitative RT-PCR and Western blotting.RESULTS: The NP cells were chondrocyte-like cellular morphology with positive staining of toluidine blue, safranine O and anti-collagen II antibody. The NP cells cultured in monolayer showed immunoreactivity to NGF either in control condition or in experimental group. IL-1β and IL-6 up-regulated the mRNA expression of NGF and the protein production of NGF. The effect of this up-regulation was higher by treating with IL-6 than by treating with IL-1β in the same concentration.CONCLUSION: Our results demonstrate that the proinflammatory cytokines IL-1β and IL-6 stimulate the production of NGF in NP cells. The effect of IL-6 is more significant than that of IL-1β.     

Immunohistochemical localization of CD14, IL-4 and TNF-α in periapical tissue of healthy individuals and patients with chronic periapical diseases

AIM: To observe the expression of cluser of differentiation 14 (CD14), tumor necrosis factor-α (TNF-α) and interleukin-4 (IL-4) in periapical tissues of patients with chronic periapical diseases, and to analyze the role of immunopathogenesis of CD14, TNF-α and IL-4 expression in human chronic periapical diseases. METHODS: A total of 88 samples were divided into 3 groups: healthy control group (n=45), chronic periapical abscess group (n=23), and periapical cyst group (n=20). All samples were fixed in 10% buffered formalin and stained with double immunofluorescence for identification of TNF-α-CD14 and IL-4-CD14 double-positive cells in periapical tissues. RESULTS: Compared with healthy control group, the densities of TNF-α-CD14 and IL-4-CD14 double-positive cells in the 2 groups of chronic periapical diseases were increased significantly (P<0.05). Compared with periapical cyst group, the density of TNF-α-CD14 double-positive cells in chronic periapical abscess was increased significantly (P<0.05). The density of IL-4-CD14 double-positive cells in periapical cyst group was significantly higher than that in chronic periapical abscess group (P<0.05). CONCLUSION: There is high expression of TNF-α-CD14 and IL-4-CD14 double-positive cells in the periapical tissues of the patients with chronic periapical abscess and perapical cyst, suggesting that the Th cytokines participate in the immune regulation of periapical diseases, which may be one of the immune mechanisms of the interaction between Th1 and Th2 cytokines.     

A study on the mechanism of doxorubicin promoting IL-1β and collagen type I secretion in cardiac fibroblasts

AIM To observe the effect of adriamycin/doxorubicin （DOX） on the production of inflammatory cytokines and collagen in cardiac fibroblasts and its mechanism. METHODS Neonatal SD rat cardiac fibroblasts were isolated, cultured, and identified by immunofluorescence staining with monoclonal antibodies against vimentin observed under a confocal laser-scanning microscope. The Cell Counting Kit-8 assay was used to detect the toxicity of DOX on cardiac fibroblasts, and flow cytometry with annexin V-FITC/PI double staining was used to detect apoptosis. ELISA was used to detect the release of inflammatory factors in the supernatant of cultured cells. Immunofluorescence labeling assay was used to detected α-smooth muscle actin （α-SMA） expression and mitochondrial reactive oxygen species （mROS） in the cells. Western blot was used to detect the expression of nucleotide-binding oligomerization domain-like receptor protein 3 （NLRP3） inflammasome-related proteins in cardiac fibroblasts. RESULTS （1） Compared with the control group, DOX inhibited the proliferation of cardiac fibroblasts （P<0.05）, but had no significant effect on apoptosis （P>0.05）. （2） Treatment with DOX promotes the release of proinflammatory factors interleukin-1β （IL-1β） and IL-6 in cardiac fibroblasts （P<0.05）. （3） The expression of α-SMA, collagen type I and transforming growth factor-β in DOX treatment group increased significantly compared with control group （P<0.05）. （4） Compared with the control group, the levels of mROS, cellular NLRP3 and cleaved caspase-1 in cardiac fibroblasts increased significantly after DOX treatment. CONCLUSION Doxorubicin promotes cardiac fibroblasts to secrete IL-1β and collagen type I by promoting mROS production and activating NLRP3 inflammasome.     

Effects of TNF-α-induced changes of expression and activity of 11-β HSD-1 on the insulin sensitivity in 3T3-L1 adipocytes

AIM: To observe the effects of tumor necrosis factor-α（TNF-α）-induced changes of expression and activity of 11-beta-hydroxysteroid dehydrogenase type1(11-β HSD-1) on the insulin sensitivity in 3T3-L1 adipocytes.METHODS: 3T3-L1 adipocytes were treated with TNF-α and TNF-α combined with aspirin, 2’-hydroxyflavanone or RU486, then mRNA expression and activity of 11-β HSD-1 and insulin-stimulated glucose uptake were examined.RESULTS: TNF-α increased expression and activity of 11-β HSD-1 in 3T3-L1 adipocytes, and decreased insulin-stimulated glucose uptake. Aspirin decreased expression and activity of 11-β HSD-1 induced by TNF-α, and alleviated the inhibiting effect of TNF-α on insulin-stimulated glucose uptake. 11-β HSD-1 specific inhibitor 2’-hydroxyflavanone and cortisol-receptor antagonist RU486 also alleviated the inhibiting effect of TNF-α on insulin-stimulated glucose uptake. CONCLUSION: TNF-α may decrease the insulin sensitivity in 3T3-L1 adipocytes through increasing expression and activity of 11-β HSD-1.     

Effect of S-nitrosylation induced by IL-1β and IFN-γ on DNA binding activity of cAMP response element binding protein in fibroblast-like synoviocytes

AIM: To investigate the effect of S-nitrosylation induced by recombinant interleukin-1β (rIL-1β) and recombinant interferon-γ (rIFN- γ) on DNA binding activity of cAMP response element binding protein (CREB) in fibroblast-like synoviocytes (FLSs). METHODS: (1)FLSs were incubated with rIL-1β and rIFN-γ in the presence or absence of inducible nitric oxide synthase inhibitor aminoguanidine (AG) for 12 h. The supernatant of the cell culture was collected to determine the contents of nitric oxide (NO). The total proteins prepared from each group ［only the total proteins prepared from rIL-1β+rIFN-γ group was reacted with dithiothreitol (DTT) for 15 min in vitro］ were subjected to the biotin switch assay, and the level of S-nitrosylation was determined by Western blotting. (2)FLSs were incubated with rIL-1β, rIL-1β+ rIFN-γ and AG respectively for 12 h. The nuclear extracts from each group were prepared. The nuclear extracts from each group were subjected to electrophoresis mobility shift assay to analyze the DNA binding activity of CREB (only the nuclear extracts from rIL-1β +rIFN-γ group was reacted with DTT for 15 min in vitro before assaying). RESULTS: rIL-1β plus rIFN-γ increased the production of NO and the level of S-nitrosylation, which was inhibited by AG. Administration of DTT in the total proteins reversed the induction of S-nitrosylation by rIL-1β and rIFN-γ. Co-incubation with rIL-1β and rIFN-γ inhibited the CREB activity induced by rIL-1β alone, which was reversed by AG. Administration of DTT in the nuclear extracts reversed the effect of co-incubation of the cytokines. CONCLUSION: Co-incubation with rIL-1β and rIFN-γ may increase the level of S-nitrosylation through inducing the production of endogenous NO, leading to reversible thiols modification of CREB and inhibit the DNA binding activity of CREB in FLSs.     

Inhibitors of CaMKⅡ suppress the expression of TNF-α, TGF-β1 and collagen I,III in cardiac fibroblasts treated with angiotensin II or electrical field stimulation

AIM: To observe the role of calcium/calmodulin-dependent protein kinase Ⅱ (CaMKⅡ) in the proliferation, released cytokines and expression of collagen Ⅰ and Ⅲ in rat cardiac fibroblasts induced by angiotensin Ⅱ (AngⅡ) or electrical field stimulation (EFS).METHODS: The cultured cardiac fibroblasts were isolated from the neonatal rats of 1-3 days and used in the 3rd passage. The cells were divided into 10 groups: control group, 0.1 μmol/L AngⅡ group, 0.1 μmol/L AngⅡ+0.5 μmol/L KN92 group, 0.1 μmol/L AngⅡ+0.5 μmol/L KN93 group, 0.1 μmol/L AngⅡ+0.5 μmol/L AIP group; 10V 1.0 Hz EFS group, 10 V 1.0 Hz EFS+0.5 μmol/L KN92 group, 10 V 1.0 Hz EFS+0.5 μmol/L KN93 group, 10 V 1.0 Hz EFS+0.5 μmol/L AIP group, 10 V 1.0 Hz EFS+0.1 μmol/L AngⅡ group.MTT was used to detect the proliferation of cardiac fibroblasts. The release of cytokines was measured by ELISA. The mRNA expression of TNF-α, TGF-β₁ and collagen Ⅰ, Ⅲ was determined by RT-PCR.RESULTS: CaMKⅡ inhibitors (0.5 μmol/L KN93 or 0.5 μmol/L AIP) prevented the proliferation and the increase in the expression of TGF-β₁ and TNF-α in cardiac fibroblasts induced by AngⅡ (0.1 μmol/L) or EFS (10 V 1.0 Hz). CaMKⅡ inhibitors (0.5 μmol/L AIP or 1.0 μmol/L AIP) also prevented the increase in mRNA expression of collagen Ⅰ and Ⅲ induced by 0.1 μmol/L AngⅡ. CONCLUSION: Inhibition of CaMKⅡ prevents the proliferation of cardiac fibroblasts induced by AngⅡ or EFS. The possible mechanism of CaMKⅡ inhibitors may be involved in preventing the mRNA expression and release of cytokines (TGF-β₁ and TNF-α), and regulating collagen I and III expression.     

Effects of ClC-3 knockdown-induced TNF-α/IL-10 imbalance in rat DRG on voltage-gated sodium channel expression and mechanical allodynia

AIM To investigate the effect of ClC-3 chloride channel/antiporter knockdown in rat dorsal root ganglion (DRG) on voltage-gated sodium channel expression in neurons and mechanical allodynia in rats. METHODS Adeno-associated virus carrying ClC-3 shRNA (AAV-ClC-3 shRNA) was injected intrathecally to knock down ClC-3 expression in DRG tissues of adult SD rats. The mRNA and protein expression levels of ClC-3, cytokines and voltage-gated sodium channels were detected by RT-qPCR, immunofluorescence and Western blot. The mechanical sensitivity was assessed using von Frey hairs and up-down method. RESULTS Intrathecal injection of AAV-ClC-3 shRNA decreased ClC-3 expression in the DRG tissues and induced mechanical allodynia in the rats. Knockdown of ClC-3 up-regulated the expression levels of Nav1.3, Nav1.7, Nav1.8 and Nav1.9 in the DRG tissues. Knockdown of ClC-3 increased tumor necrosis factor-α (TNF-α) and decreased interleukin-10 (IL-10) levels in the DRG tissues. CONCLUSION Knockdown of ClC-3 in rat DRG tissues induces TNF-α/IL-10 imbalance and increases expression of voltage-gated sodium channels, thus contributing to mechanical allodynia.     

Release of tumor necrosis factor-α in podocytes and its mechanism by mesangial cell cultured medium with IgA1 from IgA nephropathy

AIM: To explore the effect and mechanism on tumor necrosis factor-α production in podocytes by medium from growth arrested mesangial cells incubated with aIgA1 isolated from IgAN patients and normal control. METHODS: Jacalin affinity chromatography and Sephacryl S-200 molecular sieve chromatography were used to isolate IgA1. Monomeric IgA1 (mIgA1) was transformed to aggregated IgA1 (aIgA1) by heating. IgA-mesangial cell medium was prepared by collecting medium in which growth arrested mesangial cell were incubated with different aIgA1, then the medium with RPMI-1640 containing 0.5% FBS was exposed to podocytes. Real time PCR was used to detect the mRNA expression of Ang and ACE, and TNF-α was measured by ELISA assay. RESULTS: TNF-α level of podocytes by medium from aIgA1 from IgAN cultured with mesangial cells was higher than that in control (6.47±0.45) ng/L vs (1.33±0.65) ng/L, P<0.05. Ang and ACE mRNA in podocytes exposed to the special medium were higher than those in podocytes exposed to control and medium from mesangial cells incubated with aIgA1 from healthy control (P<0.05). Enalaprilat decreased the TNF-α to (7.52±1.12) ng/L (P<0.05), and valsartan decreased TNF-α in the podocytes to (6.64±0.68) ng/L (P<0.05), while enalaprilat and valsartan restored the level of TNF-α in podocytes to normal level (2.72±0.55) ng/L, P>0.05. CONCLUSION: Our findings implicate that medium from mesangial cells cultured with IgA1 from IgA nephropathy stimulates the release of TNF-α in podocytes by the activation of renin-angiotensin system, which might accelerate the progression of IgAN.     

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.     

Effect of compound of Epimedium, Astragalus and Radix Puerariae on expression of ADAM10 in Aβ-induced hippocampal neuron HT22 cells with or without hepcidin expression knock-down

AIM To explore the effect of compound of Epimedium, Astragalus and Radix Puerariae on the expression of a disintegrin and metalloproteinase 10 （ADAM10） in Aβ-induced hippocampal neuron HT22 cells with or without hepcidin （HAMP） expression knock-down for analyzing the pathogenesis of Alzheimer disease （AD） at cell level. METHODS Hippocampal neuron HT22 cells were cultured in vitro and randomly divided into 7 groups： control group, Aβ group （Aβ_25-35-induced HT22 cells）, RNAi group （HAMP gene was silenced in HT22 cells）, Aβ+RNAi group （HAMP gene expression in Aβ_25-35-induced HT22 cells was silenced）, Aβ+TCM group （Aβ_25-35-induced HT22 cells were treated with Epimedium, Astragalus root and Radix Puerariae effective components）, RNAi+TCM group （HT22 cells with HAMP gene silence were treated with Epimedium, Astragalus root and Radix Puerariae effective components） and Aβ+RNAi+TCM group （Aβ_25-35-induced HT22 cells with HAMP gene silence were treated with Epimedium, Astragalus root and Radix Puerariae effective components）. The silence efficiency of HAMP siRNA was detected by qPCR and Western blot. The ADAM10 expression in each group was determined by immunofluorescence, qPCR and Western blot. RESULTS The HAMP siRNA-3 sequence had the highest interference efficiency. Compared with control group, the expression levels of ADAM10 in Aβ group, RNAi group and Aβ+RNAi group were decreased （P<0.05）. Compared with Aβ group,the expression levels of ADAM10 in Aβ+RNAi group was also decreased （P<0.05）, and the expression levels of ADAM10 in Aβ+TCM group was increased （P<0.05）. Compared with RNAi group, the expression levels of ADAM10 in Aβ+RNAi group was decreased （P<0.05）, while the expression levels of ADAM10 in RNAi+TCM group was increased （P<0.05）. Compared with Aβ+RNAi group, the expression levels of ADAM10 in Aβ+RNAi+TCM group was increased （P<0.05）. CONCLUSION The effective components of Epimedium, Astragalus and Radix Puerariae compound promotes the expression of ADAM10 in Aβ_25-35-induced HT22 cells, which mechanism may be related to the expression of HAMP.