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Background: Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic synovitis, cartilage degradation and bone deformities. Synovitis is the term for inflammation of the synovial membrane, an early stage of RA. The pathogenesis of the disease occurs through cytokine induction. The major cytokine that increases the severity of RA is TNF-α. Thus, inhibition of the TNF-α cascade is an effective way to diminish the progression of the disease. We are interested in investigating the difference between primary human synovial fibroblast (hSF) cells and SW982 as synovitis models induced by TNF-α and in monitoring their responses to sesamin as an anti-inflammatory phytochemical. Method: The designed experiments were performed in hSF cells or the SW982 cell line treated with 10 ng/ml TNF-α with or without 0.25, 0.5 or 1 μM sesamin. Subsequently, pro-inflammatory cytokine genes and proteins were measured in parallel with a study of associated signalling transduction involved in inflammatory processes, including NF-κBand MAPK pathways. Results: The results demonstrated that although hSF and SW982 cells responded to TNF-α inductioninthesamefashion, they reacted at different levels. TNF-α could induce IL-6, IL-8 and IL-1β in both cell types, but the levels in SW982 cells were much higher than in hSF cells. This characteristic was duetothedifferentinductionofMAPKsineachcelltype. Both cell types reacted to sesamin in almost the same fashion. However, hSF cells were more sensitive to sesamin than SW982 cells in terms of the anti-RA effect. Conclusions: The responses of TNF-α-induced hSF and SW982 were different at the signal transduction level. However, the two cell types showed almost the same reaction to sesamin treatment in terms of the end point of the response. [ABSTRACT FROM AUTHOR]

Background Cartilage tissue engineering offers new strategies in repairing damaged cartilage. Scaffolds have been used for the in vitro and in vivo procedures for this application, which demonstrates the compatible biological and physical properties that mimic natural tissues. Several types of scaffolds were used and had different effects on cell functions. The study was designed to develop a functional gelatin scaffold by adsorption of hyaluronan (HA) and the transforming growth factor ß3 (TGF-ß3) in a commercially available gelatin scaffold. Results The biological properties of human articular chondrocytes were investigated during a 21-day cultivation embedded in either HA + TGF-ß3 adsorbed scaffolds or the conventional supplemented method. The rising of proliferation of chondrocytes embedded in adsorbed scaffolds was observed at day 17 and 21 of cultivation (1.27 and 1.28 fold, respectively). The chondrogenic gene expression of the chondrocytes embedded in HA + TGF-ß3 adsorbed scaffolds significantly increased: SOX-9 (1.65 fold), ACAN (7.65 fold) and COL2A1 (1.83 fold). Remarkably, over the 21 days of cultivation, HA + TGF-ß3 adsorbed scaffolds promoted the extracellular matrix molecules production with higher accumulation of HA (1.2 fold), collagen (1.42 fold) and uronic acid (1.41 fold). Moreover, the cell population and extracellular matrix production, which were examined by a histological analysis and a scanning electron microscope, were correlated with the biochemical analysis. Conclusion A small amount of HA and TGF-ß3 initially adsorbed in the scaffolds (70 pg and 10 ng, respectively) was consumed over the 21-day cultivation. The HA + TGF-ß3 adsorbed gelatin scaffold is effective and more suitable than the conventional supplemented method for the in vitro assessment of human chondrocyte 3D culture. [ABSTRACT FROM AUTHOR]

Background: Autologous chondrocyte transplantation is a promising technique for treatment of cartilage defects. Three dimensional chondrocyte cultures on a scaffold are widely used to retain the chondrogenic phenotype.Using a biodegradable gelatin scaffold is one option for the cell delivery system, but molecular and histological studies of the method have not yet been done. Methods: We evaluated the chondrogenic property of the primary human chondrocyte on a gelatin scaffold as compared to a collagen scaffold over a period of 21 days. We examined the production of glycosaminoglycan by quantitative and histological analysis. Gene expression of cartilage-associated molecules was assessed by quantitative RT-PCR.Results: The gelatin scaffold showed the ability to promote chondrocyte expansion, chondrogenic phenotype retention at molecular and mRNA levels. Conclusions: This scaffold is thus suitable for use as an in vitro model for chondrocyte 3D culture. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a worldwide health problem predominantly affecting post-menopausal women. Therapies aimed at increasing bone mass in osteoporetic patients lag behind comparable investigation of therapeutic strategies focusing on the bone resorption process. Sesamin, a major lignan compound found in Sesamun indicum Linn., has a variety of pharmacological effects, though its activity on bone cell function is unclear. Herein we examine the effect of this lignan on osteoblast differentiation and function. Method: Cell cytotoxicity and proliferative in hFOB1.19 were examined by MTT and alamar blue assay up to 96 h of treatment. Gene expression of COL1, ALP, BMP-2, Runx2, OC, RANKL and OPG were detected after 24 h of sesamin treatment. ALP activity was measured at day 7, 14 and 21 of cultured. For mineralized assay, ADSCs were cultured in the presence of osteogenic media supplement with or without sesamin for 21 days and then stained with Alizarin Red S. MAPK signaling pathway activation was observed by using western blotting. Results: Sesamin promoted the gene expression of COL1, ALP, OCN, BMP-2 and Runx2 in hFOB1.19. On the other hand, sesamin was able to up-regulate OPG and down-regulate RANKL gene expression. ALP activity also significantly increased after sesamin treatment. Interestingly, sesamin induced formation of mineralized nodules in adipose derived stem cells (ADSCs) as observed by Alizarin Red S staining; this implies that sesamin has anabolic effects both on progenitor and committed cell stages of osteoblasts. Western blotting data showed that sesamin activated phosphorylation of p38 and ERK1/2 in hFOB1.19. Conclusions: The data suggest that sesamin has the ability to trigger osteoblast differentiation by activation of the p38 and ERK MAPK signaling pathway and possibly indirectly regulate osteoclast development via the expression of OPG and RANKL in osteoblasts. Therefore, sesamin may be a promising phytochemical that could be developed for supplementation of osteoporotic therapy. [ABSTRACT FROM AUTHOR]

Background: Zearalenone (ZEA) is a phytoestrogen from Fusarium species. The aims of the study was to identify mode of human leukemic cell death induced by ZEA and the mechanisms involved. Methods: Cell cytotoxicity of ZEA on human leukemic HL-60, U937 and peripheral blood mononuclear cells (PBMCs) was performed by using 3-(4,5-dimethyl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Reactive oxygen species production, cell cycle analysis and mitochondrial transmembrane potential reduction was determined by employing 2',7'-dichlorofluorescein diacetate, propidium iodide and 3,3'-dihexyloxacarbocyanine iodide and flow cytometry, respectively. Caspase-3 and -8 activities were detected by using fluorogenic Asp-Glu-Val-Asp-7-amino-4- methylcoumarin (DEVD-AMC) and Ile-Glu-Thr-Asp-7-amino-4-methylcoumarin (IETD-AMC) substrates, respectively. Protein expression of cytochrome c, Bax, Bcl-2 and Bcl-xL was performed by Western blot. The expression of proteins was assessed by two-dimensional polyacrylamide gel-electrophoresis (PAGE) coupled with LC-MS2 analysis and realtime reverse transcription polymerase chain reaction (RT-PCR) approach. Results: ZEA was cytotoxic to U937 > HL-60 > PBMCs and caused subdiploid peaks and G1 arrest in both cell lines. Apoptosis of human leukemic HL-60 and U937 cell apoptosis induced by ZEA was via an activation of mitochondrial release of cytochrome c through mitochondrial transmembrane potential reduction, activation of caspase-3 and -8, production of reactive oxygen species and induction of endoplasmic reticulum stress. Bax was up regulated in a time-dependent manner and there was down regulation of Bcl-xL expression. Two-dimensional PAGE coupled with LC-MS2 analysis showed that ZEA treatment of HL-60 cells produced differences in the levels of 22 membrane proteins such as apoptosis inducing factor and the ER stress proteins including endoplasmic reticulum protein 29 (ERp29), 78 kDa glucose-regulated protein, heat shock protein 90 and calreticulin, whereas only ERp29 mRNA transcript increased. Conclusion: ZEA induced human leukemic cell apoptosis via endoplasmic stress and mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Background: Glucosamine (GlcN) is a well-recognized candidate for treatment of osteoarthritis. However, it is currently used in derivative forms, such as glucosamine-hydrochloride (GlcN-HCl) or glucosamine sulfate (GlcN-S). However, the molecular mode of action remains unclear. In this study, we compared the effects of Glucose (Glc), Glucuronic acid (GlcA), Glucosamine hydrochloride (GlcN-HCl) and Glucosamine sulfate (GlcN-S) on cartilage degradation. Methods: Porcine cartilage explants were co-cultured with recombinant human IL-1β and each tested substance for 3 days. HA, s-GAG and MMP-2 releases to media were measured using ELISA, dye-binding assay and gelatin zymography, respectively. Similar studies were performed in a human articular chondrocytes (HAC) monolayer culture, where cells were co-treated with IL-1β and each reagent for 24 hours. Subsequently, cells were harvested and gene expression measured using RT-PCR. All experiments were carried out in triplicate. Student's t-tests were used for statistical analysis. Results: In cartilage explants treated with IL-1β, GlcN-S had the highest chondroprotective activity of all four chemicals as shown by the inhibition of HA, s-GAG and MMP-2 released from cartilage. The anabolic (aggrecan core protein; AGG, SOX9) and catabolic (MMP-3, -13) genes in HACs treated with IL-1β and with/without chemicals were studied using RT-PCR. It was found that, GlcN-HCl and GlcN-S could reduce the expression of both MMP-3 and -13 genes. The IL-1β induced-MMP-13 gene expression was decreased maximally by GlcN-S, while the reduction of induced-MMP-3 gene expression was greatest with GlcN-HCl. Glc and GlcA reversed the effect of IL-1β on the expression of AGG and SOX9, but other substances had no effect. Conclusion: This study shows that glucosamine derivatives can alter anabolic and catabolic processes in HACs induced by IL-1β. GlcN-S and GluN-HCl decreased induced MMP-3 and -13 expressions, while Glc and GlcA increased reduced-AGG and SOX9 expression. The chondroprotective study using porcine cartilage explant showed that GlcN-S had the strongest effect. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have reported on the health benefits of sesamin, a major lignin found in sesame (S. indicum) seeds. Recently, sesamin was shown to have the ability to promote chondroitin sulfate proteoglycan synthesis in normal human chondrocytes. This study assesses the anti-inflammatory effect of sesamin on proteoglycans production in 3D chondrocyte cultures., Methods: To evaluate the effects of sesamin on IL-1β-treated human articular chondrocytes (HAC) pellets, the pellets were pre-treated with IL-1β then cultured in the presence of various concentrations of sesamin for 21 days. During that period, the expression of IL-1β, glycosaminoglycans (GAGs) content and Chondroitin sulfate proteoglycans (CSPGs) synthesis genes (ACAN, XT-1, XT-2, CHSY1 and ChPF) was measured. The GAGs accumulation in the extracellular matrix was determined on day 21 by histological analysis., Results: There was clear evidence that sesamin upregulated expression of all the CSPGs synthesis genes, in contrast to the down-regulation of IL-1β expression both in genes and in protein levels. The level of release and matrix accumulation of GAGs in IL-1β pre-treated HAC pellets in the presence of sesamin was recovered. These results correlate with the histological examination which showed that sesamin enhanced matrix CSPGs accumulation., Conclusions: Sesamin enhances CSPGs synthesis, suppresses IL-1β expression and ameliorates IL-1β induced inflammation in human chondrocytes. Sesamin could have therapeutic benefits for treating inflammation in osteoarthritis.

Background: Rheumatoid arthritis (RA) is an autoimmune disease associated with chronic inflammatory arthritis. TNF-α and OSM are pro-inflammatory cytokines that play a key role in RA progression. Thus, reducing the effects of both cytokines is practical in order to relieve the progression of the disease. This current study is interested in sesamin, an active compound in sesame seeds. Sesamin has been shown to be a chondroprotective agent in osteoarthritis models. Here, we have evaluated a porcine cartilage explant as a cartilage degradation model related to RA induced by TNF-α and/or OSM in order to investigate the effects of sesamin on TNF-α and OSM in the cartilage degradation model., Methods: A porcine cartilage explant was induced with a combination of TNF-α and OSM (test group) or IL-1β and OSM (control group) followed by a co-treatment of sesamin over a long-term period (35 days). After which, the tested explants were analyzed for indications of both the remaining and the degradation aspects using glycosaminoglycan and collagen as an indicator., Results: The combination of TNF-α and OSM promoted cartilage degradation more than either TNF-α or OSM alone and was comparable with the combination of IL-1β and OSM. Sesamin could be offering protection against cartilage degradation by reducing GAGs and collagen turnover in the generated model., Conclusions: Sesamin might be a promising agent as an alternative treatment for RA patients. Furthermore, the generated model revealed itself to be an impressive test model for the analysis of phytochemical substances against the cartilage degradation model for RA. The model could be used to test for the prevention of cartilage degradation in other biological agents induced with TNF-α and OSM as well.

Background: The purpose of this study was to compare two biochemical markers, which have been previously used to determine the degrees of alveolar bone destruction, in evaluating periodontal disease severity., Methods: The WF6 epitope of chondroitin sulfate (CS) and the alkaline phosphatase (ALP) levels were determined in gingival crevicular fluid (GCF) samples collected from patients with various degrees of disease severity, including ten patients with gingivitis (50 gingivitis sites) and 33 patients with chronic periodontitis (including gingivitis, slight, moderate, and severe periodontitis sites; n = 50 each), as well as from ten healthy volunteers (50 healthy sites) by Periopaper strips. The levels of CS and ALP were measured by an ELISA and a fluorometric assay, respectively., Results: The results demonstrated low levels of CS and ALP in non-destructive and slightly destructive periodontitis sites, whereas significantly high levels of these two biomolecules were shown in moderately and severely destructive sites (p < 0.05). Although a significant difference in CS levels was found between moderate and severe periodontitis sites, no difference in ALP levels was found. Stronger correlations were found between CS levels and periodontal parameters, including probing depth, loss of clinical attachment levels, gingival index and plaque index, than between ALP levels and these parameters., Conclusions: It is suggested that the CS level is a better diagnostic marker than the ALP level for evaluating distinct severity of chronic periodontitis.

Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various tumor cells, but does not affect normal cells or human leukemic cells, such as MOLT-4 and U937 cells, which are relatively resistant to TRAIL. Three flavonoids extracted from the rhizome of K. parviflora were 5,7-dimethoxyflavone (DMF), 5,7,4'-trimethoxyflavone (TMF) and 3,5,7,3',4'-pentamethoxyflavone (PMF), and synthetic flavonoids including 5-methoxyflavone (5-MF) and 2'-methoxyflavone (2"-MF) were chosen for testing in this study. The aims of this study were to examine whether the treatment of TRAIL-resistant leukemia MOLT-4 and U937 cells, with methoxyflavone derivatives could enhance the apoptotic response and to identify the mechanism involved., Methods: The cytotoxic effect of methoxyflavone (MF) derivatives in MOLT-4, U937 and peripheral blood mononuclear cells (PBMCs) was analyzed by the MTT assay. The induction of apoptosis and the reduction of mitochondrial transmembrane potential (ΔΨm) after staining with annexin V FITC and propidium iodide (PI), and 3,3'-dihexyloxacarbocyanine iodide (DiOC(6)), respectively, were performed using flow cytometry. ROS production was determined by staining with 2',7'-dichlorofluorescin diacetate and processed with a flow cytometer. DR4, DR5, cFLIP, Mcl-1, BAX and Bid expression were demonstrated by immunoblotting. Caspase-8 and -3 activities were determined by using IETD-AFC and DEVD-AFC substrates and the fluorescence intensity was measured., Results: All methoxyflavone derivatives were cytotoxic to MOLT-4, U937 cells and PBMCs, except DMF, TMF and PMF were not toxic to PBMCs. All MF derivatives induced human leukemic MOLT-4 cell apoptosis, but not in U937 cells. Percentage of MOLT-4 cells with (ΔΨm) was increased when treated with DMF, TMF, PMF, 5-MF and 2'-MF in the presence of TRAIL. 5-MF and 2'-MF enhanced TRAIL-induced apoptosis through the up-regulation of both DRs and the down-regulation of cFLIP and Mcl-1. Bid was cleaved and BAX was up-regulated, followed by the activation of caspase-8 and -3. Oxidative stress was also increased. 2'-MF gave the same result compared with 5-MF but with a less effect., Conclusion: Methoxyflavone derivatives enhanced TRAIL-induced apoptosis in human leukemic MOLT-4 cells through the death receptors and mitochondrial pathways.

Introduction: The purpose of this study was to evaluate serum chondroitin sulfate (CS) and hyaluronic acid (HA) levels and the capability of cartilage repair of full-thickness cartilage defects after treatment with two different fundamental surgical techniques: autologous chondrocyte transplantation (AC) and subchondral drilling (SD)., Methods: A 4-mm-diameter full-thickness cartilage defect was created in each of 10 skeletally mature male outbred dogs. The dogs were randomly separated into two groups. Groups A and B were treated with AC and SD, respectively. An evaluation was made at the 24th week of the experiment. Serum was analyzed prospectively--preoperatively and at 6-week intervals--for CS and HA levels by enzyme-linked immunosorbent assay (ELISA) and ELISA-based assays, respectively., Results: The cartilage repair assessment score (median +/- standard deviation) of group A (9.5 +/- 2.5) was significantly higher than that of group B (2.5 +/- 1.3) (P < 0.05). Group A also demonstrated a better quality of hyaline-like cartilage repair. Prospective analysis of serum WF6 and HA levels between the two groups did not show any significant difference. Serum WF6 levels at the 24th week of the experiment had a negative correlation (r = -0.69, P < 0.05) with the cartilage repair assessment score, whereas serum HA levels tended to correlate positively (r = 0.46, 0.1