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51.
Osteoarthritis (OA) is a degenerative joint disease leading to joint pain and stiffness. Due to lack of effective treatments, physical and psychological disabilities caused by OA have a detrimental impact on the patient’s quality of life. Emerging evidence suggests that intra-articular injection of platelet-rich plasma (PRP) may provide favorable results since PRP comprises not only a high level of platelets but also a huge amount of cytokines, chemokines, and growth factors. However, the precise mechanism and standardization method remain uncertain. This study aimed to examine cytokine profiling in both PRP and platelet-poor plasma (PPP) of knee OA patients and to determine the effects of PRP on OA chondrocytes and knee OA patients. PRP contained a wide variety of cytokines, chemokines, growth factors, and autologous intra-articular PRP injection resulted in favorable outcomes in knee OA patients. Significant increases in levels of IL-1, IL-2, IL-7, IL-8, IL-9, IL-12, TNF-α, IL-17, PDGF-BB, bFGF, and MIP-1β were detected in PRP compared to PPP (p < 0.001). An in vitro study showed a marked increase in proliferation in OA chondrocytes cultured with PRP, compared to PPP and fetal bovine serum (p < 0.001). In a clinical study, knee OA patients treated with PRP showed improvement of physical function and pain, assessed by physical performance, Western Ontario and McMaster Universities Arthritis Index and visual analog scale. Our findings from both in vitro and clinical studies suggest that intra-articular PRP injection in knee OA patients may be a potential therapeutic strategy for alleviating knee pain and delaying the need for surgery.  相似文献   
52.
Osteoarthritis is a progressive disease characterized by cartilage destruction in the joints. Matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) play key roles in osteoarthritis progression. In this study, we screened a chemical compound library to identify new drug candidates that target MMP and ADAMTS using a cytokine-stimulated OUMS-27 chondrosarcoma cells. By screening PCR-based mRNA expression, we selected 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide as a potential candidate. We found that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated IL-1β-induced MMP13 mRNA expression in a dose-dependent manner, without causing serious cytotoxicity. Signaling pathway analysis revealed that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated ERK- and p-38-phosphorylation as well as JNK phosphorylation. We then examined the additive effect of 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide in combination with low-dose betamethasone on IL-1β-stimulated cells. Combined treatment with 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide and betamethasone significantly attenuated MMP13 and ADAMTS9 mRNA expression. In conclusion, we identified a potential compound of interest that may help attenuate matrix-degrading enzymes in the early osteoarthritis-affected joints.  相似文献   
53.
Synovial fluid (SF) represents the primary source of nutrients of articular cartilage and is implicated in maintaining cartilage metabolism. We investigated the effects of SF, from patients with osteoarthritis (OA), rheumatoid arthritis (RA), and controls, on a pattern of microRNA (miRNA) in human OA chondrocytes. Cells were stimulated with 50% or 100% SF for 24 h and 48 h. Apoptosis and superoxide anion production were detected by cytometry; miRNA (34a, 146a, 155, 181a), cytokines, metalloproteinases (MMPs), type II collagen (Col2a1), antioxidant enzymes, B-cell lymphoma (BCL)2, and nuclear factor (NF)-κB by real-time PCR. The implication of the NF-κB pathway was assessed by the use of NF-κB inhibitor (BAY-11-7082). RA and OA SF up-regulated miR-34a, -146a, -155, -181a, interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, MMP-1, MMP-13, and ADAMTs-5 gene expression, while it down-regulated Col2a1. Pathological SF also induced apoptosis, reduced viability, and decreased BCL2 mRNA, whereas it increased superoxide anions, the expression of antioxidant enzymes, p65 and p50 NF-κB. Opposite and positive results were obtained with 100% control SF. Pre-incubation with BAY-11-7082 counteracted SF effects on miRNA. We highlight the role of the SF microenvironment in regulating some miRNA involved in inflammation and cartilage degradation during OA and RA, via the NF-κB pathway.  相似文献   
54.

目的:骨关节炎(Osteoarthritis,OA)是一种常见的慢性关节性疾病,本研究旨在探究银耳多糖对骨关节炎细胞模型人软骨细胞T/C-28a2的增殖效应和抗炎作用。方法:通过MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide)和结晶紫染色实验检测银耳多糖对T/C-28a2细胞增殖活力和细胞毒性的影响;用脂多糖(Lipopolysaccharide,LPS)处理T/C-28a2细胞建立骨炎症模型,酶联免疫吸附测定(Enzyme-linked immunosorbent assay,ELISA)检测药物处理后细胞白介素-6(Interleukin-6,IL-6)的表达;利用蛋白免疫印迹(Western blot)检测药物处理后相关骨保护因子和炎症因子的表达;通过ROS活性氧释放实验检测药物对细胞的氧化应激水平和抗炎症反应。结果:银耳多糖能够促进人软骨细胞T/C-28a2的增殖活力,且没有明显的细胞毒性;使用LPS刺激软骨细胞模拟骨炎症的环境,药物处理后发现银耳多糖和硫酸软骨素处理能减少IL-6分泌从而抑制炎症发生;进一步Western blot检测发现银耳多糖刺激后,相关骨保护因子(Osteoprotegerin,OPG)的表达上调,而促凋亡相关蛋白Bax、细胞外信号调节激酶(Extracellular-signal-regulated kinases,ERK-MAPK)和核内转录因子κB(Nuclear factor-kappaB,NF-κB)的表达下调。活性氧(Reactive oxygen species,ROS)释放实验结果显示,银耳多糖和硫酸软骨素能够抑制细胞内ROS水平,抑制炎症反应的发生。结论:银耳多糖具有抑制骨关节炎的效用,可以在一定程度上保护软骨组织,抵抗细胞凋亡。本研究初步探讨了银耳多糖的抗炎作用及机制,为开发银耳多糖作为抗炎药物提供初步的实验依据。

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56.
Background: In recent decades, hyaluronic acid (HA) has attracted great attention as a new treatment option for osteoarthritis. Classical therapies are not able to stop the cartilage degeneration process nor do they favor tissue repair. Nowadays, it is accepted that high molecular weight HA can reduce inflammation by promoting tissue regeneration; therefore, the aim of this study was to verify the efficacy of a new high molecular weight HA of plant origin (called GreenIuronic®) in maintaining joint homeostasis and preventing the harmful processes of osteoarthritis. Methods: The bioavailability of GreenIuronic® was investigated in a 3D intestinal barrier model that mimics human oral intake while excluding damage to the intestinal barrier. Furthermore, the chemical significance and biological properties of GreenIuronic® were investigated in conditions that simulate osteoarthritis. Results: Our data demonstrated that GreenIuronic® crosses the intestinal barrier without side effects as it has a chemical–biological profile, which could be responsible for many specific chondrocyte functions. Furthermore, in the osteoarthritis model, GreenIuronic® can modulate the molecular mechanism responsible for preventing and restoring the degradation of cartilage. Conclusion: According to our results, this new form of HA appears to be well absorbed and distributed to chondrocytes, preserving their biological activities. Therefore, the oral administration of GreenIuronic® in humans can be considered a valid strategy to obtain beneficial therapeutic effects during osteoarthritis.  相似文献   
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An innovative modification of the wet inversion phase method, consisting in the use of a polymer nano-nonwoven as a nonclassic pore precursor. Mechanical properties of the obtained scaffolds were determined, their hydrophilic properties (serum absorbability) were tested, and the content of residues of materials used in the scaffold preparation was determined. Nontoxicity of the developed scaffolds toward T lymphocyte cells was proved. Cultures of primary chondrocytes were obtained successfully. It was proved that an addition of a polymer nano-nonwoven changes the properties of the scaffolds favorably in respect of their subsequent application in tissue engineering.  相似文献   
59.
The glucosamine derivative 2-(N-Acetyl)-L-phenylalanylamido-2-deoxy-β-D-glucose (NAPA), was shown to inhibit the kinase activity of IKKα, one of the two catalytic subunits of IKK complex, decreasing the inflammatory status in osteoarthritis chondrocytes. In the present work we have investigated the inhibition mechanism of IKKα by NAPA by combining computational simulations, in vitro assays and Mass Spectrometry (MS) technique. The kinase in vitro assay was conducted using a recombinant IKKα and IKKtide, a 20 amino acid peptide substrate derived from IkBα kinase protein and containing the serine residues Ser32 and Ser36. Phosphorylated peptide production was measured by Ultra Performance Liquid Chromatography coupled with Mass Spectrometry (UPLC-MS), and the atomic interaction between IKKα and NAPA has been studied by molecular docking and Molecular Dynamics (MD) approaches. Here we report that NAPA was able to inhibit the IKKα kinase activity with an IC50 of 0.5 mM, to decrease the Km value from 0.337 mM to 0.402 mM and the Vmax from 0.0257 mM·min1 to 0.0076 mM·min1. The computational analyses indicate the region between the KD, ULD and SDD domains of IKKα as the optimal binding site explored by NAPA. Biochemical data indicate that there is a non-significant difference between Km and Ki whereas there is a statistically significant difference between the two Vmax values. This evidence, combined with computational results, consistently indicates that the inhibition is non-competitive, and that the NAPA binding site is different than that of ATP or IKKtide.  相似文献   
60.
Hop (Humulus lupulus L.) is a plant used as an ingredient in beer or employed for its anti-inflammatory properties. The cultivation of hops is currently dedicated to the brewing industry, where mainly female flowers are used, whereas aerial parts, such as leaves, are considered coproducts. Osteoarthritis is the most common musculoskeletal disease associated with low-grade cartilage inflammation. Liposomes have been shown to be promising systems for drug delivery to cartilage cells, called chondrocytes. The aim of our work was to vectorize hop extract valorized from coproducts as a therapeutic agent to alleviate inflammation in human chondrocytes in vitro. Liquid chromatography allowed the identification of oxidized bitter acids in a methanolic extract obtained from the leaves of Cascade hops. The extract was encapsulated in rapeseed lecithin nanoliposomes, and the physicochemical properties of empty or loaded nanoliposomes exhibited no difference. Increasing concentrations of the hop extract alone, empty nanoliposomes, and loaded nanoliposomes were tested on human chondrocytes to assess biocompatibility. The appropriate conditions were applied to chondrocytes stimulated with interleukin-1β to evaluate their effect on inflammation. The results reveal that encapsulation potentiates the hop extract anti-inflammatory effect and that it might be able to improve joint inflammation in osteoarthritis. Furthermore, these results also show that a “zero waste” chain is something that can be achieved in hop cultivation.  相似文献   
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