Ragweed pollen induces allergic conjunctivitis immune tolerance in mice via regulation of the NF-κB signal pathway

AIM:To investigate the feasibility and mechanism of immune tolerance in allergic conjunctivitis.METHODS:The allergic conjunctivitis immune tolerance mice model was established by ragweed pollen(RW)and the related cytokines were detected.The mice were divided into 9 groups and the maslinic acid(MA)or PBS were given for different group after modeling.The expression levels of chemokine ligand 5(CCL5)and P-65 in the conjunctival tissue were analyzed by immunohistochemistry,quantitative reverse transcription polymerase chain reaction(q RT-PCR)and Western blot.The percentage of interleukin-17(IL-17)and CD4+CD25+in the splenocyte supernatant was analyzed by flow cytometry.Fur thermore,the serum and splenocyte supernatant concentration of total-IgE,interleukin-10(IL-10),and IL-17 was analyzed by enzyme linked immune response(ELISA).RESULTS:After the model was established,symptoms of conjunctivitis were alleviated,the level of P-65,CCL5,IL-17,and total-IgE was raised,while the expression of IL-10,CD4+CD25+was decreased.This result fully demonstrated that a typical IL-17/regulatory-T-cells(Treg cells)imbalance and NF-κB activation.When the NF-κB signal pathway was suppressed,it showed that there was a further relief of conjunctivitis in mice.At the same time,the expression of total-IgE,IL-17,and CCL5 was decreased and the expression of anti-inflammatory factor(IL-10,CD4+CD25+)was increased.CONCLUSION:In the state of immune tolerance,symptoms of conjunctivitis in mice are alleviated,the Th-17 cells of allergic conjunctivitis mice are inhibited,and Treg cells activity is enhanced.

Inhibitory Effect of Bergenin on TLR-4/NF-κB Signal Pathway in Reducing Allergic Rhinitis in Mice

[Objectives]To explore the effect and possible mechanism of bergenin in relieving allergic rhinitis(AR)in mice.[Methods]50 C57/BL6 mice were randomly divided into blank group(n=10),model group(n=10)and high(100 mg/kg),medium(50 mg/kg)and low(25 mg/kg)dose bergenin groups with 10 mice in each group.Except for the blank group,the other mice were sensitized by basic ways combined with attack to replicate the AR model.From the 15th d of modeling(from the second d after the end of the basic modeling),the drug group was given bergenin orally for 15 d,and the blank group and model group were given the same volume of normal saline once a day.24 h after the last establishment of the model,the content of interleukin 4(IL-4),IL-6,TNF-αand IL-1βin nasal lavage fluid and serum of mice in each group was detected by ELISA.The expression of TLR-4,NF-κB and p-NF-κB in nasal mucosa of mice was detected by Western blot.[Results]Compared with the blank group,the content of inflammatory factors IL-4,IL-6,TNF-αand IL-1βin nasal lavage fluid and serum of model group was significantly increased,and the protein expression of TLR-4 and p-NF-κB was significantly increased.After the intervention of bergenin,the content of IL-4,IL-6,TNF-αand IL-1βin nasal lavage fluid and serum and TLR-4 and p-NF-κB protein in tissue was significantly inhibited in bergenin group.[Conclusions]Bergenin can effectively reduce allergic inflammation in AR model mice,and its mechanism may be related to inhibition of inflammation and down-regulation of TLR-4/NF-κB signal pathway.

Downregulation of MUC1 Inhibits Proliferation and Promotes Apoptosis by Inactivating NF-κB Signaling Pathway in Human Nasopharyngeal Carcinoma

Objective To investigate the effect of mucin 1(MUC1)on the proliferation and apoptosis of nasopharyngeal carcinoma(NPC)and its regulatory mechanism.Methods The 60 NPC and paired para-cancer normal tissues were collected from October 2020 to July 2021 in Quanzhou First Hospital.The expression of MUC1 was measured by real-time quantitative PCR(qPCR)in the patients with PNC.The 5-8F and HNE1 cells were transfected with siRNA control(si-control)or siRNA targeting MUC1(si-MUC1).Cell proliferation was analyzed by cell counting kit-8 and colony formation assay,and apoptosis was analyzed by flow cytometry analysis in the 5-8F and HNE1 cells.The qPCR and ELISA were executed to analyze the levels of TNF-αand IL-6.Western blot was performed to measure the expression of MUC1,NFкB and apoptosis-related proteins(Bax and Bcl-2).Results The expression of MUC1 was up-regulated in the NPC tissues,and NPC patients with the high MUC1 expression were inclined to EBV infection,growth and metastasis of NPC.Loss of MUC1 restrained malignant features,including the proliferation and apoptosis,downregulated the expression of p-IкB、p-P65 and Bcl-2 and upregulated the expression of Bax in the NPC cells.Conclusion Downregulation of MUC1 restrained biological characteristics of malignancy,including cell proliferation and apoptosis,by inactivating NF-κB signaling pathway in NPC.

Kuicolong-yu enema decoction retains traditional Chinese medicine enema attenuates inflammatory response ulcerative colitis through TLR4/NF-κB signaling pathway

BACKGROUND Ulcer colitis(UC)is a chronic,nonspecific,and noninfectious inflammatory bowel disease.Recently,Toll-like receptors(TLRs)have been found to be closely associated with clinical inflammatory diseases.Achieving complete remission in patients with intermittent periods of activity followed by dormancy is challenging.Moreover,no study has explored the mechanism by which Kuicolong-yu enema decoction retains traditional Chinese medicine enemas to attenuate the inflammatory response in UC.AIM To explore the mechanism by which Kuicolong-yu enema decoction retains traditional Chinese medicine enemas to attenuate the inflammatory response in UC.METHODS This prospective clinical study included patients who met the exclusion criteria in 2020 and 2021.The patients with UC were divided into two groups(control and experimental).The peripheral blood of the experimental and control groups were collected under aseptic conditions.The expression of TLR4 protein,NF-κB,IL-6,and IL-17 was detected in the peripheral blood of patients in the experimental group and control group before and 1 month after taking the drug.Linear co rrelation analysis was used to analyze the relationship between the expression level of TLR4 protein and the expression levels of downstream signal NF-κB and inflammatory factors IL-6 and IL-17,and P<0.05 was considered statistically significant.RESULTS There were no significant differences in the patient characteristics between the control and experimental groups.The results showed that the expression levels of TLR4 and NF-κB in the experimental group were significantly lower than those in the control group(P<0.05).The levels of IL-6 and IL-17 in the experimental group were significantly lower than those in the control group(P<0.05).The TLR4 protein expression in the experimental group was positively correlated with the expression level of downstream signal NF-κB and was positively correlated with the levels of downstream inflammatory cytokines IL-6 and IL-17(r=0.823,P<0.05).CONCLUSION Kuicolong-yu enema decoction retains traditional Chinese medicine enema attenuates the inflammatory response of UC through the TLR4/NF-κB signaling pathway.

Aszonapyrone A Isolated from Neosartorya spinosa IFM 47025 Inhibits the NF-κB Signaling Pathway Activated by Expression of the Ependymoma-Causing Fusion Protein ZFTA-RELA

Ependymoma is a rare and chemotherapy-resistant brain tumor, which has resulted in a delay in the development of drugs to treat it. A subclass of supratentorial ependymomas (ST-EPN), designated ST-EPN-zinc finger-translocation-associated (ZFTA, ST-EPN-ZFTA), exhibits the expression of a fusion protein comprising ZFTA and v-rel reticuloendotheliosis viral oncogene homolog A (RELA), an effector transcription factor of the nuclear factor-kappa B (NF-κB) pathway (ZFTA-RELA). The expression of ZFTA-RELA results in the hyperactivation of the oncogenic NF-κB signaling pathway, which ultimately leads to the development of ST-EPN-ZFTA. To identify inhibitors of the NF-κB signaling pathway activated by the expression of ZFTA-RELA, we used a doxycycline-inducible ZFTA-RELA-expressing NF-κB reporter cell line and found that extracts of the fungus Neosartorya spinosa IFM 47025 exhibited NF-κB inhibitory activity. We identified eight compounds [aszonapyrone A (2), sartorypyrone A (3), epiheveadride (4), acetylaszonalenin (5), (R)-benzodiazepinedione (6), aszonalenin (7), sartorypyrone E (8) and (Z, Z)-N,N’-(1,2-bis[(4-methoxyphenyl)methylene]-1,2-ethanediyl)bis-formamide (9)] from N. spinosa IFM 47025 culture extract using a variety of chromatographic techniques. The structures of these compounds were identified through the analysis of various instrumental data (1D, 2D-NMR, MS, and optical rotation). The NF-κB responsive reporter assay indicated that compounds 2, 3, 5, 7, and 9 exhibited inhibitory activity. We further evaluated the inhibitory activity of these compounds against the expression of endogenous NF-κB responsive genes (CCND1, L1CAM, ICAM1, and TNF) and found that compound 2 showed significant inhibitory activity. Further studies are required to elucidate the mechanism of action of compound 2, which may serve as a lead compound for the development of a novel therapy for ST-EPN-ZFTA.

Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways

BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy options are still lacking.Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1(NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis,but its role in diseases including hepatic fibrosis remains undefined.Therefore,additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.AIM To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.METHODS Twenty-four male C57BL/6 mice were randomized and separated into three groups,comprising the normal,fibrosis,and calcitriol treatment groups,and liver fibrosis was modeled by carbon tetrachloride(CCl4).To evaluate the level of hepatic fibrosis in every group,serological and pathological examinations of the liver were conducted.TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells.NS3TP1,α-smooth muscle actin(α-SMA),collagen I,and collagen Ⅲ in every group were examined using a Western blot and real-time quantitative polymerase chain reaction.The activity of the transforming growth factor beta 1(TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected.The statistical analysis of the data was performed using the Student’s t test.RESULTS NS3TP1 promoted the activation,proliferation,and differentiation of hepatic stellate cells(HSCs)and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways,as evidenced by the presence of α-SMA,collagen I,collagen Ⅲ,p-smad3,and p-p65 in LX-2 cells,which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference.The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression,as shown by the luciferase assay.NS3TP1 inhibited the apoptosis of HSCs.Moreover,both Smad3 and p65 could bind to NS3TP1,and p65 increased the promoter activity of NS3TP1,while NS3TP1 increased the promoter activity of TGFβ1 receptor I,as indicated by coimmunoprecipitation and luciferase assay results.Both in vivo and in vitro,treatment with calcitriol dramatically reduced the expression of NS3TP1.Calcitriol therapy-controlled HSCs activation,proliferation,and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice.Furthermore,calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.CONCLUSION Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique,prospective therapeutic target in hepatic fibrosis.

Acupuncture at Back-Shu point improves insomnia by reducing inflammation and inhibiting the ERK/NF-κB signaling pathway

BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use is prone to drug resistance and other adverse reactions.Acupuncture has a good curative effect and unique advantages in the treatment of insomnia.AIM To explore the molecular mechanism of acupuncture at Back-Shu point for the treatment of insomnia.METHODS We first prepared a rat model of insomnia,and then carried out acupuncture for 7 consecutive days.After treatment,the sleep time and general behavior of the rats were determined.The Morris water maze test was used to assess the learning ability and spatial memory ability of the rats.The expression levels of inflammatory cytokines in serum and the hippocampus were detected by ELISA.qRTPCR was used to detect the mRNA expression changes in the ERK/NF-κB signaling pathway.Western blot and immunohistochemistry were carried out to evaluate the protein expression levels of RAF-1,MEK-2,ERK1/2 and NF-κB.RESULTS Acupuncture can prolong sleep duration,and improve mental state,activity,diet volume,learning ability and spatial memory.In addition,acupuncture increased the release of 1L-1β,1L-6 and TNF-αin serum and the hippocampus and inhibited the mRNA and protein expression of the ERK/NF-κB signaling pathway.CONCLUSION These findings suggest that acupuncture at Back-Shu point can inhibit the ERK/NF-κB signaling pathway and treat insomnia by increasing the release of inflammatory cytokines in the hippocampus.

基于HMGB1/TLR4/NF-κB通路研究鱼油延缓气道重塑治疗哮喘的作用机制

目的:探讨鱼油通过HMGB1/TLR4/NF-κB信号通路延缓气道重塑,治疗哮喘的潜在作用机制及其疗效,为哮喘的新型治疗策略提供理论依据和实验支持。方法:采用Ovalbumin(OVA)诱导的哮喘小鼠模型,随机分为对照组、模型组、鱼油组、鱼油+E5564组,每组10只,共40只;4组小鼠,通过肺功能测试仪对比气道阻力,酶联免疫吸附试验判断运用TLR4抑制剂前后的IL-1β、IL-6、TNF-α、IL-10炎症因子水平,苏木精—伊红染色观察肺组织病理变化,逆转录定量聚合酶链反应对比Bax、caspase-3、Bcl2的mRNA表达水平,免疫印迹分析观察Bax、caspase-3、Active-caspase3、HMGB1、TLR4、NF-κB、p-NF-κB p65的蛋白表达量,免疫组化法观察HMGB1、TLR4、NF-κB的蛋白表达水平。结果:气道阻力测试表明,鱼油组小鼠的气道阻力显著降低,肺组织病理损伤减轻,炎症细胞浸润明显减少;HE染色结果表明降低,鱼油组小鼠的气道损伤更小,炎症细胞浸润和上皮细胞排列紊乱更少;ELISA结果显示,鱼油组小鼠的血清炎症因子IL-1β、IL-6、TNF-α的表达降低,并提高了IL-10的表达,而鱼油+E5564组的血清炎症因子水平与模型组相近;RT-qPCR结果表明,鱼油组小鼠的Bax、caspase-3的mRNA表达量较低,Bcl2的mRNA表达量较高;WB结果表明,鱼油组小鼠的Bax、caspase-3、Active-caspase3、HMGB1、TLR4、NF-κB、p-NF-κB p65蛋白表达量更低,而鱼油+E5564组小鼠HMGB1、TLR4、NF-κB及p-NF-κB p65蛋白表达量与模型组小鼠相近;IHC结果表明,鱼油组小鼠HMGB1、TLR4、NF-κB蛋白表达量更低,与WB结果趋同。结论:鱼油通过影响HMGB1/TLR4/NF-κB信号通路,显著减轻哮喘小鼠模型的气道炎症和重塑,提高肺功能,显示出作为哮喘潜在治疗剂的可能性;该研究为鱼油在哮喘治疗领域的应用提供了实验依据,但需要进一步的临床研究来验证其疗效和安全性。

丹参多酚酸盐调控NF-κB信号通路对冠心病大鼠心肌细胞凋亡的影响

目的 探讨丹参多酚酸盐调控NF-κB信号通路对冠心病大鼠心肌细胞凋亡的影响。方法 选取60只健康雄性的SD大鼠,将其随机分为对照组、模型组、阳性对照组及丹参多酚酸盐低、中、高剂量组,每组10只。模型组、阳性对照组、丹参多酚酸盐低中高剂量组在连续6周每天喂食高脂饲料后每隔24 h腹腔注射30μg/kg垂体后叶素,连续3次,建立模型。丹参多酚酸盐低、中、高剂量组分别给予50、150和450 mg/L丹参多酚酸盐,阳性对照组给予10 mg/kg瑞舒伐他汀,对照组采用常规饮食。观察各组大鼠心肌梗死面积、心肌细胞凋亡情况、心肌组织中炎性因子表达、心肌组织中超氧化物歧化酶(SOD)、丙二醛(MDA)表达、NF-κB通路相关蛋白及mRNA表达。结果 与对照组相比,模型组梗死心肌组织/危险区(IS/AAR)、凋亡率、炎症因子水平较高(P<0.05);与模型组相比,丹参多酚酸盐各剂量组有所改善(P<0.05)。与对照组相比,模型组SOD较低,MDA较高(P<0.05);与模型组相比,丹参多酚酸盐各剂量组SOD较高,MDA较低(P<0.05)。与对照组相比,模型组NF-κB p65、NF-κB蛋白及mRNA表达较高(P<0.05);与模型组相比,丹参多酚酸盐各剂量组NF-κB p65、NF-κB蛋白及mRNA表达较低(P<0.05)。结论 丹参多酚酸盐可有效抑制冠心病大鼠心肌细胞凋亡,其作用机制与NF-κB信号通路有关。

补虚化瘀方及其拆方对脂多糖诱导的人肝内胆管上皮细胞TLR4/MyD88/NF-κB信号通路的影响

目的 观察补虚化瘀方及其拆方对脂多糖(LPS)诱导的人肝内胆管上皮细胞(HIBEC)细胞外基质及TLR4/MyD88/NF-κB信号通路的影响,探讨其改善原发性胆汁性胆管炎(PBC)炎症病变的相关机制。方法 将48只SD大鼠随机分为空白组、补虚组、化瘀组、补虚化瘀方组,每组12只。补虚组、化瘀组、补虚化瘀方组分别灌以相应中药水煎液,空白组灌以等量的生理盐水,每日1次,连续灌胃2周,灌胃结束后取血制备含药血清;将不同处理因素的HIBEC分为正常组、模型组(5μg/mL脂多糖)、补虚组、化瘀组、补虚化瘀方组;CCK8法筛选最佳干预浓度,检测各组细胞活力;免疫荧光检测各组NF-κB激活-核转运状态;Western blot检测各组TLR4、MyD88、NF-κB p65、P-NF-κB p65目的蛋白的表达;酶联免疫吸附测定法(ELISA)测定各组细胞培养上清液中IL-6、IL-8、MCP-1、CXCL10的含量。结果 (1) CCK8结果显示,15%含药血清为最佳干预浓度;与正常组及模型组相比,化瘀组细胞活力增加(P<0.05),补虚化瘀方组细胞活力增加明显(P<0.01);(2)免疫荧光检测显示,与正常组比较,模型组NF-κB亚基从细胞浆大量转运到细胞核内,光密度明显增强(P<0.01);与模型组、补虚组、化瘀组相比,补虚化瘀方含药血清组转运到细胞核内的NF-κB亚基明显减少,光密度减弱(P<0.01);(3) Western blot结果显示,与正常组比较,模型组TLR4、MyD88、NF-κB p65、P-NF-κB p65蛋白表达增加(P<0.01);与模型组比较,补虚组NF-κB p65、P-NF-κB p65蛋白表达减少(P<0.01),化瘀组P-NF-κB p65蛋白表达减少(P<0.01),补虚化瘀方组TLR4、MyD88、NF-κB p65、P-NF-κB p65蛋白表达明显减少(P<0.01);(4) ELISA检测显示,与正常组比较,模型组IL-6、IL-8、MCP-1、CXCL10分泌增多(P<0.01);与模型组比较,补虚组、化瘀组IL-6、MCP-1、CXCL10分泌减少(P<0.01),补虚化瘀方组IL-6、IL-8、MCP-1、CXCL10分泌明显减少(P<0.05,P<0.01)。结论 相对于模型组、补虚组、化瘀组,补虚化瘀方全方组能增加HIBEC的细胞活力,显著抑制脂多糖诱导的HIBEC中IL-6、IL-8、MCP-1、CXCL10的分泌,方中补虚、化瘀两组药物存在协同作用,全方可发挥最大疗效,其机制可能与抑制TLR4/MyD88/NF-κB信号通路的激活密切相关。

Apigenin ameliorates imiquimod-induced psoriasis in C57BL/6J mice by inactivating STAT3 and NF-κB

Psoriasis is a chronic autoimmune disease featured by patches on the skin.It is caused by malfunction of immune cells and keratinocytes with inflammation as one of its key features.Apigenin(API)is a natural flavonoid with anti-inflammatory and immunoregulatory properties.Therefore,we speculated that API can ameliorate psoriasis,and determined its effect on the development of psoriasis by using imiquimod(IMQ)-induced psoriasis mouse model.Our results showed that API attenuated IMQ-induced phenotypic changes,such as erythema,scaling and epidermal thickening,and improved splenic hyperplasia.Abnormal differentiation of immune cells was restored in API-treated mice.Mechanistically,we revealed that API is a key regulator of signal transducer activator of transcription 3(STAT3).API regulated immune responses by reducing interleukin-23(IL-23)/STAT3/IL-17A axis.Moreover,it suppressed IMQ-caused cell hyperproliferation by inactivating STAT3 through regulation of extracellular signal-regulated kinase 1/2 and nuclear factor-κB(NF-κB)pathway.Furthermore,API reduced expression of inflammatory cytokines through inactivation of NF-κB.Taken together,our study demonstrates that API can ameliorate psoriasis and may be considered as a strategy for psoriasis treatment.

IKIP downregulates THBS1/FAK signaling to suppress migration and invasion by glioblastoma cells

Background:Inhibitor of NF-κB kinase-interacting protein(IKIP)is known to promote proliferation of glioblastoma(GBM)cells,but how it affects migration and invasion by those cells is unclear.Methods:We compared levels of IKIP between glioma tissues and normal brain tissue in clinical samples and public databases.We examined the effects of IKIP overexpression and knockdown on the migration and invasion of GBM using transwell and wound healing assays,and we compared the transcriptomes under these different conditions to identify the molecular mechanisms involved.Results:Based on data from our clinical samples and from public databases,IKIP was overexpressed in GBM tumors,and its expression level correlated inversely with survival.IKIP overexpression in GBM cells inhibited migration and invasion in transwell and wound healing assays,whereas IKIP knockdown exerted the opposite effects.IKIP overexpression in GBM cells that were injected into mouse brain promoted tumor growth but inhibited tumor invasion of surrounding tissue.The effects of IKIP were associated with downregulation of THBS1 mRNA and concomitant inhibition of THBS1/FAK signaling.Conclusions:IKIP inhibits THBS1/FAK signaling to suppress migration and invasion of GBM cells.

Involvement of ayu NOD2 in NF-κB and MAPK signaling pathways: Insights into functional conservation of NOD2 in antibacterial innate immunity

Nucleotide oligomerization domain 2(NOD2) is a major cytoplasmic sensor for pathogens and is critical for the clearance of cytosolic bacteria in mammals.However, studies regarding NOD2, especially the initiated signaling pathways, are scarce in teleost species. In this study, we identified a NOD2 molecule(PaNOD2) from ayu(Plecoglossus altivelis).Bioinformatics analysis showed the structure of NOD2 to be highly conserved during vertebrate evolution. Dual-luciferase reporter assays examined the activation of NF-κB signaling and Western blotting analysis detected the phosphorylation of three MAP kinases(p-38, Erk1/2, and JNK1/2).Functional study revealed that, like its mammalian counterparts, PaNOD2 was the receptor of the bacterial cell wall component muramyl dipeptide(MDP), and the leucine-rich repeat motif was responsible for the recognition and binding of Pa NOD2 with the ligand. Overexpression of PaNOD2 activated the NF-κB signaling pathway, leading to the upregulation of inflammatory cytokines, including TNF-α and IL-1β in HEK293 T cells and ayu head kidney-derived monocytes/macrophages(MO/MΦ).Particularly, we found that PaNOD2 activated the MAPK signaling pathways, as indicated by the increased phosphorylation of p-38, Erk1/2, and JNK1/2, which have not been characterized in any teleost species previously. Our findings proved that the NOD2 molecule and initiated pathways are conserved between mammals and ayu. Therefore, ayu could be used as an animal model to investigate NOD2-based diseases and therapeutic applications.

β-arrestin 2 attenuates lipopolysaccharide-induced liver injury via inhibition of TLR4/NF-κB signaling pathwaymediated inflammation in mice

AIM To study the role and the possible mechanism of β-arrestin 2 in lipopolysaccharide(LPS)-induced liver injury in vivo and in vitro.METHODS Male β-arrestin 2^(+/+) and β-arrestin 2^(-/-)C57 BL/6 J mice were used for in vivo experiments, and the mouse macrophage cell line RAW264.7 was used for in vitro experiments. The animal model was established via intraperitoneal injection of LPS or physiological sodium chloride solution. Blood samples and liver tissues were collected to analyze liver injury and levels of pro-inflammatory cytokines. Cultured cell extracts were collected to analyze the production of pro-inflammatory cytokines and expression of key molecules involved in the TLR4/NF-κB signaling pathway.RESULTS Compared with wild-type mice, the β-arrestin 2 knockout mice displayed more severe LPS-induced liver injury and significantly higher levels of proinflammatory cytokines, including interleukin(IL)-1β, IL-6, tumor necrosis factor(TNF)-α, and IL-10. Compared with the control group, pro-inflammatory cytokines(including IL-1β, IL-6, TNF-α, and IL-10) produced by RAW264.7 cells in the β-arrestin 2 si RNA group were significantly increased at 6 h after treatment with LPS. Further, key molecules involved in the TLR4/NF-κB signaling pathway, including phosphoIκBα and phosho-p65, were upregulated.CONCLUSION β-arrestin 2 can protect liver tissue from LPS-induced injury via inhibition of TLR4/NF-κB signaling pathwaymediated inflammation.

Immunoregulatory polysaccharides from Apocynum venetum L.flowers stimulate phagocytosis and cytokine expression via activating the NF-κB/MAPK signaling pathways in RAW264.7 cells

Two immunomodulatory polysaccharides(Vp2a-Ⅱ and Vp3) were isolated and identified from Apocynum venetum L. flowers, and their innate immune-stimulating functions and working mechanisms were evaluated in RAW264.7 cells. Both the level of released nitric oxide(NO) and expression of inducible nitric oxide synthase(iNOS) m RNA were significantly enhanced in the RAW264.7 macrophages cells treated by Vp2a-Ⅱ and Vp3. Vp2a-Ⅱ(100–800 μg/m L) and Vp3(400 μg/mL) could significantly increase the phagocytic activity of RAW264.7 cells and the secretion and m RNA expression of TNF-α and IL-6 in a concentrationdependent manner through affecting mitogen-activated protein kinase(MAPK) activity and nuclear factor κB(NF-κB) nuclear translocation. Vp2a-Ⅱ might activate the MAPK signaling pathways and induce the nuclear translocation of NF-κB p65, whilst Vp3 likely activated the NF-κB and MAPK signaling pathways without influencing the p38 MAPK route.

Low-temperature Plasma Promotes Fibroblast Proliferation in Wound Healing by ROS-activated NF-κB Signaling Pathway

Low-temperature plasma(LTP)has shown great promise in wound healing,although the underlying mechanism remains poorly understood.In the present study,an argon atmospheric pressure plasma jet was employed to treat L929 murine fibroblasts cultured in vitro and skin wounds in BALB/c mice.The in vitro analysis revealed that treatment of fibroblasts with LTP for 15 s resulted in a significant increase in cell proliferation,secretion of epidermal growth factor(EGF)and transforming growth factor-β1(TGF-β1),production of intracellular reactive oxygen species(ROS),and the percentage of cells in S phase,protein expression of phosphorylated p65(P-p65)and cyclin D1,but a noted decrease in the protein expression of inhibitor kappa B(IκB).The in vivo experiments demonstrated that 30-s LTP treatment enhanced the number of fibroblasts and the ability of collagen synthesis,while 50-s treatment led to the opposite outcomes.These results suggested that LTP treatment promotes the fibroblast proliferation in wound healing by inducing the generation of ROS,upregulating the expression of P-p65,downregulating the expression of IκB,and activating the NF-κB signaling pathway and consequently altering cell cycle progression(increased DNA synthesis in S phage).

黄连素调节PI3K/AKT/NF-κB信号通路对慢性湿疹大鼠皮肤损伤的影响

目的探讨黄连素对慢性湿疹大鼠皮肤损伤及磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(AKT)/核因子-κB(NF-κB)信号通路的影响。方法60只SD大鼠分为对照组,慢性湿疹组,黄连素低、中、高剂量组和泼尼松组,每组10只。除对照组外,其余组大鼠背部涂抹2,4-二硝基氯苯(DNCB)构建慢性湿疹模型。进行湿疹面积及严重度指数(EASI)评分;酶联免疫吸附试验(ELISA)检测血清组胺、胃泌素释放肽(GRP)、免疫球蛋白E(IgE)、白细胞介素(IL)-4、IL-6、肿瘤坏死因子α(TNF-α)、γ干扰素(IFN-γ)水平;苏木素-伊红(HE)染色观察皮损组织病理学改变;Western blot法检测皮损组织PI3K/AKT/NF-κB信号通路相关蛋白表达。结果与对照组比较,慢性湿疹组大鼠皮损组织受损严重,血清组胺、GRP、IgE、IL-4、IL-6、TNF-α水平以及皮损组织IL-4、IL-6、TNF-α蛋白表达和p-PI3K/PI3K、p-AKT/AKT、p-NF-κB p65/NF-κB p65、p-NF-κB抑制蛋白α(IκBα)/IκBα比值升高,血清和皮损组织IFN-γ降低(P<0.05)。与慢性湿疹组比较,黄连素各剂量组和泼尼松组大鼠皮损组织病理损伤有所改善,EASI评分下降,血清组胺、GRP、IL-4、IL-6、TNF-α水平以及皮损组织IL-6、TNF-α蛋白表达和p-PI3K/PI3K、p-AKT/AKT、p-NF-κB p65/NF-κB p65、p-IκBα/IκBα比值降低,血清和皮损组织IFN-γ升高(P<0.05),同时黄连素中、高组和泼尼松组大鼠血清IgE和皮损组织IL-4降低(P<0.05),且黄连素高剂量组效果更好;黄连素高剂量组和泼尼松组上述指标比较差异无统计学意义(P>0.05)。结论黄连素尤其是高剂量黄连素可抑制PI3K/AKT/NF-κB信号通路激活,减轻免疫失衡和炎症反应,改善慢性湿疹大鼠皮肤损伤。

Effect of dexmedetomidine on the prevention of PSH in patients with severe craniocerebral injury by regulating TLR4/My D88/NF-kappa B signaling pathway

Objective:To investigate the clinical efficacy of dexmedetomidine in the regulation of TLR4/My D88/NF-κB in the prevention of paroxysmal sympathetic over-excitation (PSH) in patients with severe head injury. Methods:One hundred patients with severe head injury who were admitted to our hospital from September 2016 to May 2019 were enrolled. The randomized digital table method was divided into 50 cases in the study group and the control group. Patients in the study group were given dexmedetomidine at a dose of 1.0 μg/kg before anesthesia induction, followed by infusion at 0.4 μg / (kg·h), and the control group was injected with the same amount of normal saline. The incidence of PSH, clinical symptoms, imaging findings, mechanical ventilation time, tracheal intubation/incision duration, ICU hospitalization time, total length of hospital stay, and GCS scores three months after discharge were compared between the two groups. At the same time, the fluorescence intensity, TLR4, NF-κB expression level and tumor necrosis factor-α (TNF-α) expression levels in peripheral blood CD14+ monocytes of the two groups were detected. Results:The incidence of PSH was significantly lower in the study group than in the control group at 7 and 3 months (P<0.05). The total length of hospital stay, duration of ICU hospitalization, intraoperative tracheotomy, and mechanical ventilation time were significantly lower in the study group than in the control group. And the GCS score was higher than the control group, and the difference was statistically significant (P<0.05). In addition, the imaging results showed that there were some differences in the location of imaging lesions between the two groups. The proportion of lesions in the ventricular system and surrounding areas was higher in the control group than in the study group (P<0.05). And the T14-T3 CD14+ PBMC MyD88 fluorescence intensity, TLR4 and NK-κB positive expression rate were significantly higher than those of T0 (P<0.05), but the MyD88 fluorescence intensity, TLR4 and NK-κB positive expression rate in the study group were significantly lower than those in the control group at T1~T3 (P<0.05). The levels of serum TNF-α in T1~T3 groups were significantly higher than those in T0 (P<0.05), but the levels of serum TNF-α in T1~T3 in the study group were significantly lower than those in the control group (P< 0.05). Conclusions:Dexmedetomidine can reduce the oxidative stress response in patients with severe head injury by inhibiting TLR4/My D88/NF-κB signaling pathway, thus effectively reducing the risk of PSH and improving the prognosis of patients.

Mechanism and effect of curcumin on apoptosis of EAE mice by regulating TLRs/NF-κB signaling pathway

Objective:To investigate theanti apoptosis effect of curcumin(cur)in experimental autoimmune encephalomyelitis(EAE)mice by regulating TLRs/NF-κB signaling pathway and its mechanism.Methods:45 C57BL/6 mice were randomly divided into the control group,EAE group,curcumin group,15 mice in each group.Blank groups are not processed.The EAE model was established by classical modeling method in the EAE group and the curcumin group.From the day of modeling,the blank group and the EAE group were intraperitoneally injected with 1ml/kg/d of normal saline,Curcumin group was given 100 mg/kg/d continuous intraperitoneal injection of curcumin extract.With Benson EAE group and Curcumin group mice were killed at the peak of the disease.The blank group and the rest of the mice were killed after 4 weeks of feeding,and the spinal cord tissue was taken out to separate the lumbar enlargement segment.The effects of curcumin on the pathological changes of spinal cord tissue in EAE mice were observed by HE staining and TUNEL staining,and the expression of apoptosis positive cells was calculated.The distribution and co aggregation of apoptosis related proteins Bcl-2 and Bax with spinal cord tissue were observed by double immunofluorescence staining The protein levels of TLR4,NF-κBp65 and MyD88 were detected by Western blot.Results:compared with the blank group,TUNEL staining increased the number of apoptotic cells and the apoptotic rate in EAE group(P<0.05);the expression of apoptosis related protein Bcl-2 decreased and the expression of Bax increased in EAE group(P<0.05),The protein of TLR4,NF-κBp65 and MyD88 in spinal cord tissue of mice were increased by blot detection(P<0.05);compared with EAE group,the number of apoptotic cells in spinal cord tissue of curcumin group was decreased by TUNEL staining,and the apoptosis rate was decreased(P<0.05);the expression of apoptosis related protein Bcl-2 was increased,the expression of Bax protein was decreased,and Western blot was used to detect the expression of apoptosis related protein The protein of TLR4,NF-κBp65 and MyD88 in spinal cord tissue of mice were decreased by blot(P<0.05).Conclusion:Curcumin has anti apoptotic effect on EAE mice,and its mechanism may be related to the inhibition of TLRs/NF-κB signaling pathway and the reduction of apoptotic protein production.

Study on the Hepatoprotective Effect of Oxalis coriniculata L. and Related Mechanism by Regulating Oxidative Stress and TLR-2/NF-κB Signaling Pathway

[Objectives]This study aimed to explore the protective effect of Oxalis coriniculata L.on rats with acute liver injury induced by carbon tetrachloride(CCl4)and related mechanism by regulating oxidative stress and the TLR-2 TLR-2/NF-κB signaling pathway.[Methods]A total of 48 female rats were randomly and evenly divided into normal group,model group,silymarin group(0.12 g/kg),and high(16 g/kg),middle(8 g/kg)and low-dose(4 g/kg)O.coriniculata L.groups.The rats in the groups were intragastrically administered with 5 mL/kg of corresponding drugs(equal-volume distilled water for normal group and control group),respectively.The administration was conducted twice a day,for 10 consecutive days.After 2 h of the last administration,the rats in all the groups except the normal group were intraperitoneally injected with 12%carbon tetrachloride(CCl4)olive oil solution(5 mL/kg),respectively to establish liver injury rat models.After 16 h,the eyeball blood of the rats was collected,and their liver tissues were collected for preparation of HE sections.The biochemical indicators detected included aspartate aminotransferase(AST),alanine aminotransferase(ALT),total superoxide dismutase(T-SOD)and glutathione peroxidase(GSH-Px)activity and malondialdehyde(MDA)content in the serum.The contents of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin-6(IL-6)in the serum were detected by ELISA.The expression of Toll-like receptor-2(TLR-2)and nuclear factor-κB(NF-κB)in liver tissue was detected using Western blotting.The pathological changes of liver were observed under light microscope.[Results]Compared with the normal group,the ALT,AST activity and MDA,IL-1β,IL-6,TNF-αlevels in rat serum significantly increased(P<0.01),the GSH-Px,T-SOD activity in rat serum significantly decreased(P<0.01),and the expression of TLR-2 and NF-κB in liver tissue was up-regulated(P<0.01)in the model group.Compared with the model group,the ALT,AST activity and MDA,IL-1β,IL-6 and TNF-αlevels in rat serum reduced(P<0.05,P<0.01),the GSH-Px and T-SOD activity in rat serum increased(P<0.05,P<0.01),and the expression of TLR-2 and NF-κB in liver tissue was down-regulated(P<0.05,P<0.01)in the O.coriniculata L.administration groups.Pathological sections show that O.coriniculata L.had an improving effect on rats with acute liver injury induced by CCl4.[Conclusions]O.coriniculata L.has a good protective effect on rats with acute liver injury induced by CCl4.Its mechanism may be related to inhibition of oxidative stress,inhibition of inflammatory response and regulation of the TLR-2/NF-κB signaling pathway.