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1.
目的 慢性牙周炎表现的病理性骨吸收非常常见,牙周膜干细胞(PDLSCs)的外泌体(Exo)对骨吸收的作用和影响尚不明确,本研究分析了该Exo蛋白组分对破骨细胞分化的影响。方法 分别从正畸前拔牙患者和慢性牙周炎患者的牙周膜组织中提取PDLSCs,通过流式细胞术检测表面标记物;通过差速离心分别提取2种细胞的Exo,即Exo-WT和Exo-CP,并通过Western blot、透射电子显微镜(TEM)、蛋白浓度检测、纳米粒径追踪检测Exo特征;通过蛋白质谱检测2种Exo的蛋白组分;通过酶联免疫吸附(ELISA)验证了差异表达蛋白肿瘤坏死因子α(TNF-α)、核因子κB受体活化因子配体(RANKL)、白细胞介素(IL)-1α、转化生长因子β(TGF-β)、骨形态发生蛋白2(BMP-2)表达水平;将10、100、1 000 μg·mL-1的Exo-CP或Exo-WT加入RAW264.7培养基中并于5 d时通过实时荧光定量聚合酶链反应(RT-qPCR)、Western blot、抗酒石酸酸性磷酸酶(TRAP)染色检测破骨分化相关指标表达情况;采用SPSS 24.0软件对实验数据进行统计学分析。结果 Exo-CP富集的差异表达蛋白主要与破骨细胞分化的TNF信号通路、核转录因子κB(NF-κB)信号通路相关;ELISA实验证实了Exo-CP中高表达TNF-α、RANKL、IL-1α,低表达TGF-β1、BMP-2(P<0.05);Exo-CP作用于RAW264.7,显著提高了细胞的破骨分化相关基因及蛋白的表达水平,TRAP染色可见分化的破骨细胞,且呈现浓度依赖性,100、1 000 μg·mL-1浓度Exo-CP对破骨细胞分化的促进作用显著高于10 μg·mL-1浓度组(P<0.05)。结论 慢性牙周炎的病理性骨吸收可能由炎性PDLSCs所分泌的Exo通过促进破骨细胞分化引起,Exo中主要的作用蛋白可能为RANKL和TNF-α,本研究为慢性牙周炎骨吸收的发病机制提供了新视角。  相似文献   
2.
Burn injuries are underappreciated injuries associated with substantial morbidity and mortality. Overexposure to ultraviolet (UV) radiation has dramatic clinical effects in humans and is a significant public health concern. Although the mechanisms underlying UVB exposure are not fully understood, many studies have made substantial progress in the pathophysiology of sunburn in terms of its molecular aspects in the last few years. It is well established that the transient receptor potential ankyrin 1 (TRPA1), and vanilloid 1 (TRPV1) channels modulate the inflammatory, oxidative, and proliferative processes underlying UVB radiation exposure. However, it is still unknown which mechanisms underlying TRPV1/A1 channel activation are elicited in sunburn induced by UVB radiation. Therefore, in this review, we give an overview of the TRPV1/A1 channel-mediated signalling cascades that may be involved in the pathophysiology of sunburn induced by UVB radiation. These data will undoubtedly help to explain the various features of sunburn and contribute to the development of novel therapeutic approaches to better treat it.  相似文献   
3.
目的探究芒针深刺秩边穴对大鼠脊髓损伤后运动功能的影响及可能作用机制。方法选择健康雄性Wister大鼠81只,随机分为正常组、模型组和芒针组(正常组9只,其余两组各36只),采用改良Allen's造模法制备大鼠脊髓中度损伤模型,模型组不做特殊处理,芒针组采用芒针深刺秩边穴,每日1次,每次30 min。分别于术后1 d、3 d、5 d、7 d行BBB(Basso-Beattie-Bresnahan)运动功能评分;术后1 d、3 d、5 d、7 d取受损段脊髓组织行酶联免疫吸附测定(ELISA)、实时荧光定量PCR(RT-qPCR)和苏木素-伊红染色(HE染色)。结果术后5 d和7 d,芒针组大鼠BBB评分高于模型组,差异有统计学意义(P<0.01);脊髓损伤后,模型组和芒针组大鼠脊髓组织中高迁移率族蛋白B1(HMGB1)、核转录因子kB(NF-kB)、白介素-6(IL-6)含量及HMGB1mRNA、NF-kBmRNA、IL-6mRNA水平显著升高(P<0.05);受损的脊髓组织松散,灰质中有许多空洞形成,伴有炎性细胞浸润。芒针治疗后,芒针组大鼠脊髓组织中HMGB1、NF-kB、IL-6含量及HMGB1mRNA、NF-kBmRNA、IL-6mRNA水平较模型组降低,且在3 d、5 d、7 d差异有统计学意义(P<0.05);受损部位的空洞及炎性细胞逐渐减少。结论脊髓损伤后,炎症因子的大量聚集引起级联性炎症反应,影响大鼠运动功能的恢复。芒针的抗炎机制可能包括抑制HMGB1的表达,降低NF-kB信号通路的传导,下调促炎因子IL-6的分泌。  相似文献   
4.
目的观察旋覆代赭汤对反流性食管炎(RE)模型大鼠食管黏膜与脂多糖(LPS)、Toll样受体4(TLR4)、核因子κB(NF-κB)表达的影响。方法将60只雄性Wistar大鼠按随机数字表法分为正常对照组、模型组、旋覆代赭汤组(简称中药组,9.89 g/kg)、西药(奥美拉唑+莫沙比利,2.58 mg/kg)组,每组15只。除正常对照组外大鼠采用“4.2 mm幽门夹+2/3胃底结扎术”制备酸碱混合反流RE大鼠模型。术后第7天予相应药物干预,持续干预14天。利用光学显微镜观察大鼠食管下段黏膜组织形态学变化;应用ELISA法检测定外周血中LPS含量;采用Western Blot法与RT-PCR法检测食管黏膜组织中TLR4、NF-κB蛋白和基因表达。结果与正常对照组比较,模型组大鼠食管黏膜镜下损伤最为严重,食管黏膜呈炎性改变,可见急慢性炎细胞浸润,病理积分和外周血中LPS含量升高(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达升高(P<0.05)。与模型组比较,中药组、西药组病理积分和外周血中LPS含量降低(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达亦明显降低(P<0.05)。结论旋覆代赭汤能够减轻RE模型大鼠食管黏膜的损伤,抑制TLR4、NF-κB的表达,促进食管黏膜损伤的恢复。  相似文献   
5.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
6.
目的初步探讨LM49(2,4'三羟基-5,2'-二溴二苯甲酮)对脂多糖(LPS)联合干扰素γ(IFN-γ)诱导的小鼠单核巨噬细胞(RAW264.7)M1/M2极化的影响及其调控机制。方法四曱基偶氮唑蓝(MTT)法测定LM49对细胞活力的影响;流式细胞术、实时荧光定量聚合酶链反应(PCR)和Westem-blot法测定LM49(5,10,20μmol·L^-1)与LPS/INF-γ共同作用于RAW264.7细胞后,巨噬细胞亚型标志物的表达情况及对核因子(NF)-κB和JAK/STAT信号通路的影响。结果与LPS/INF-γ造模组相比,LM49显著抑制CD16/32^+细胞数及诱导型一氧化氮合酶(iNOS)、白细胞介素(IL)4和肿瘤坏死因子(TNF)-αmRNA的表达,升高CD206^+细胞数及Arg-1和IL-10 mRNA的表达,且降低巨噬细胞M1/M2的比值;Westem-blot法验证LM49可显著降低TLR4、Myd88、NF-κB和STAT1蛋白的表达量,同时抑制p-JAK2和p-STATl蛋白磷酸化水平。结论LM49通过抑制TLR4-Myd88-NF-κB和JAK2-STAT1信号通路,抑制巨噬细胞Ml型极化及促进巨噬细胞M2型极化,调节巨噬细胞M1/M2的平衡。  相似文献   
7.
目的探究双黄连对动脉粥样硬化大鼠体内TLR4/MyD88/NF-κB信号通路表达的影响。方法建立动脉粥样硬化大鼠模型,进行双黄连不同剂量的处理后,对大鼠进行相关检测。结果双黄连处理组大鼠血清中的总胆固醇、甘油三酯、高密度脂蛋白和低密度脂蛋白均明显低于模型组,高剂量组效果更明显;将胸主动脉进行HE染色后发现,相比模型组,双黄连处理组均有管腔狭窄的减轻,脂质斑块的减少,泡沫细胞沉积的减少,蓝色颗粒钙化病灶的缩小;免疫组化实验和Western Blot实验检测发现,双黄连处理组大鼠的动脉组织中TLR4、MyD88、NF-κB表达相比模型组发生了明显降低,且高剂量组降低更明显。结论双黄连有利于减轻大鼠动脉粥样硬化的病症,其机理在于降低TLR4、MyD88、NF-κB蛋白的表达水平,且疗效显著。  相似文献   
8.
目的研究五味子醇甲(SCH)对APP/PS1双转基因痴呆小鼠行为学和NF-κB p65的影响。方法将35只APP/PS1双转基因痴呆小鼠随机分为模型(APP/PS1)组、五味子醇甲(SCH+APP/PS1)组;另以同背景同月龄的C 57 BL/6 J阴性小鼠为空白(WT)组。SCH+APP/PS1组给予SCH悬浊液灌胃(2.6 mg·kg^-1·d^-1),模型组和空白组给予等量蒸馏水灌胃。各组灌胃30 d进行Mirror水迷宫空间探索试验后取材。HE染色法观察皮层及海马CA1区神经细胞的形态结构。运用DCFH-DA法检测脑组织活性氧(ROS)含量。Western印迹检测法检验磷酸化核转录因子(NF-κB p65,pp65)的表达。结果与APP/PS 1组相比,APP/PS 1+SCH组有效区停留距离及时间明显延长,差异有统计学意义(P<0.05,P<0.01);APP/PS 1+SCH组穿越有效区次数和平台区停留距离增加,均差异有统计学意义(P<0.01)。APP/PS 1+SCH组HE染色观察皮层有部分神经细胞萎缩、减少,较APP/PS1组明显好转,海马细胞排列整齐度尚可、较均匀。与APP/PS1组相比,APP/PS1+SCH组能降低ROS含量,差异有统计学意义(P<0.05)。APP/PS 1+SCH组皮层及海马pp65蛋白相对表达量下调(P<0.05,P<0.01)。结论SCH可能通过降低ROS含量和抑制pp65保护脑组织形态结构和提高APP/PS1鼠空间探索记忆能力。  相似文献   
9.
Ras-specific guanine nucleotide-releasing factor 2 (RasGRF2) is a member of the guanine nucleotide exchange factors family which is expressed in a variety of tissues and cancer. However, the role of RasGRF2 in cancer is less reported, especially in colorectal cancer(CRC). Hence, the present study aimed to investigated the function of RasGRF2 and ways in which it affects tumor progression in CRC samples and cell lines. We first measured RasGRF2 mRNA level in 26 paired tumor and nontumor colon tissues after colon cancer surgical resection, and determined RasGRF2 protein level in 97 paired paraffin-embedded colon cancer tissues, and found that levels of RasGRF2 mRNA and protein were increased in colorectal tumor tissues, compared with adjacent non-tumor tissues. We then examined the effects of RasGRF2 knockdown on proliferation, migration and invasion were analyzed in CRC cells (SW480, HCT116 and LS174T). HCT116 cells with RasGRF2 knockdown were injected into the tail vein in nude mice to yield metastatic model, and tumor metastasis was measured as well. We found that knockdown of RasGRF2 in CRC cells reduced their migration and invasion in vitro and metastasis in mice. Furthermore, we explored the underlying molecular mechanism for RasGRF2-mediated CRC migration and invasion. The results showed that knockdown of RasGRF2 in CRC cells impairing the expression of MMP9 and inhibiting the activation of Src/Akt and NF-κB signaling. We conclude that RasGRF2 plays a role in controlling migration and invasion of CRC and modulates the expression of MMP9 through Src/PI 3-kinase and the NF-κB pathways.  相似文献   
10.
Osteoarthritis (OA) is a progressive and degenerative joint disease. Aloin is a bitter and yellow-brown-coloured compound from the Aloe plant and is allowed for use in foods as a “natural flavour”. In our study, we examined the protective effects of Aloin on the inhibition of OA development as well as its underlying mechanism in both in vitro and vivo experiments. In in-vitro experiments, the protective effect of aloin on the anabolism and catabolism of the extracellular matrix (ECM) induced by IL-1 β in chondrocytes by inhibiting the expression of pro-inflammatory factors, including TNF-α (p = 0.016), IL-6 (p = 0.006), iNOS (p = 0.001) and COX-2 (p = 0.006). Mechanistically, Aloin suppressed the IL-1β-induced activation of the PI3K/Akt/NF-κB signalling pathway cascades. Moreover, molecular docking studies demonstrated that Aloin bound strongly to PI3K. In vivo, Aloin ameliorated the OA process in the destabilization of the medial meniscus (DMM) model.In summary, our findings demonstrate that Aloin ameliorates the progression of OA via the PI3K/Akt/NF-κB signalling pathways, which supports Aloin as a promising therapeutic agent for the treatment of OA.  相似文献   
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