Cartilage biology, pathology, and repair

Protective effect of resveratrol against IL-1β-induced inflammatory response on human osteoarthritic chondrocytes partly via the TLR4/MyD88/NF-κB signaling pathway: an "in vitro study"

Resveratrol is a natural polyphenolic compound that prevents inflammation in chondrocytes and animal models of osteoarthritis (OA) via yet to be defined mechanisms. The purpose of this study was to determine whether the protective effect of resveratrol on IL-1β-induced human articular chondrocytes was associated with the TLR4/MyD88/NF-κB signaling pathway by incubating human articular chondrocytes (harvested from osteoarthritis patients) with IL-1β before treatment with resveratrol. Cell viability was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and TNFα levels in culture supernatants were measured by ELISA(Enzymelinked immunosorbent assay). The levels of TLR4 and its downstream signaling targets (MyD88 and TRAF6) and IL-1β were assessed by measuring the levels of mRNA and protein expression by real-time RT-PCR and western blot analysis, respectively, in addition to assessing NF-κB activation. In addition, TLR4 siRNA was used to block TLR4 expression in chondrocytes further demonstrating that resveratrol prevented IL-1β-mediated inflammation by TLR4 inhibition. We found that resveratrol prevented IL-1β-induced reduction in cell viability. Stimulation of chondrocytes with IL-1β caused a significant up-regulation of TLR4 and its downstream targets MyD88 and TRAF6 resulting in NF-κB activation associated with the synthesis of IL-1β and TNFα. These IL-1β-induced inflammatory responses were all effectively reversed by resveratrol. Furthermore, activation of NF-κB in chondrocytes treated with TLR4 siRNA was significantly attenuated, but not abolished, and exposure to resveratrol further reduced NF-κB translocation. These data suggested that resveratrol prevented IL-1β-induced inflammation in human articular chondrocytes at least in part by inhibiting the TLR4/MyD88/NF-κB signaling pathway suggesting that resveratrol has the potential to be used as a nutritional supplement to counteract OA symptoms.

Polyethylene wear particles play a role in development of osteoarthritis via detrimental effects on cartilage, meniscus, and synovium

OBJECTIVE

While ultra-high molecular weight polyethylene (UHMWPE) wear particles are known to cause periprosthetic osteolysis, its interaction with other intra-articular tissues in the case of partial joint arthroplasties is not well understood. We hypothesized that UHMWPE particles per se would interact with intra-articular tissue, which by acting as inflammatory reservoirs, would subsequently induce osteoarthritic (OA) changes. Our goal was to assess the inflammatory response, phagocytic activity, as well as apoptosis of intra-articular cells in the presence of UHMWPE particles in vitro, and the in vivo response of those tissues after intra-articular injection of particles in a murine model.

DESIGN

Three cell types were used for the in vitro study; chondrocytes, meniscal fibrochondrocytes, and synoviocytes. Each cell type was cultured with two different concentrations of UHMWPE particles. Pro-inflammatory cytokine production, phagocytosis, and apoptosis were analyzed. In vivo experiments were done by injecting two concentrations of UHMWPE particles into normal and murine OA model knee joints.

RESULTS

In vitro experiments showed that UHMWPE particles increase pro-inflammatory cytokine and mediator (IL-1β, IL-6, TNF-α, Nitric Oxide, and Prostaglandin E2) production, phagocytosis of particles, and apoptosis in all cell types. In vivo experiment showed degeneration of cartilage and meniscus, as well as synovitis after particle injection.

CONCLUSIONS

UHMWPE wear particles per se exert detrimental effects in cartilage, synovium, and meniscus of the knee joint resulting in pro-inflammatory cytokine release, phagocytosis of particles and apoptosis. Particles induced and exacerbated OA changes in a murine model.

Exogenous bFGF promotes articular cartilage repair via up-regulation of multiple growth factors

OBJECTIVE

To investigate the roles of exogenous basic fibroblast growth factor (bFGF) on the repair of full-thickness articular cartilage defects in rabbits.

DESIGN

In the present study, a double-layered collagen membrane sandwiched with bFGF-loaded-nanoparticles between a dense layer and a loose layer was implanted into full-thickness articular cartilage defects in rabbits. By grafting the membrane in a different direction, the dense layer or the loose layer facing the surface of the subchondral bone, the effects of the released bFGF on the defects and the profiles of nine growth factors (GFs) in synovial fluid (SF) were investigated using histological methods and antibody arrays, respectively.

RESULTS

In the group with the loose layer facing the surface of the subchondral bone, fast release of bFGF was observed, and early high levels of endogenous transforming growth factor-β2 (TGF-β2), vascular endothelial growth factor (VEGF), bFGF, bone morphogenetic protein 2 (BMP-2), BMP-3, and BMP-4 in SF were detected by antibody arrays, especially on day 3. Chondrocyte-like cells were also observed in this group at an early stage. As a result, this group showed better levels of repair, as compared to the other groups in which low GF levels were detected at an early stage, and chondrocyte-like cells appeared much later.

CONCLUSIONS

Our study suggests that exogenous bFGF promotes articular cartilage repair by up-regulating the levels of multiple GFs, but administration at an early stage is required.

Mesenchymal stem cell chondrogenesis: composite growth factor-bioreactor synergism for human stem cell chondrogenesis

BACKGROUND

Effective mesenchymal stem cell chondrogenesis can be accomplished by using a tailored mechanical-biochemical stimulus. To achieve this requires parallel suppression of hypertrophy and osteogenesis.

MATERIALS & METHODS

We compared the effects of isolated bioreactor stimulation, isolated growth factor (TGF-β1 or IGF-1) application and their combined stimulation on human bone marrow-derived mesenchymal stem cells cultured within 3D scaffolds. Free-swelling cell-matrix constructs underwent identical growth factor stimulation for control.

RESULTS

Mechanical stimulation provoked stronger chondrogenic differentiation than free-swelling culture. Chondrogenesis by the addition of TGF-β1 was enhanced compared with single physical stimulation. There were no such effects under the influence of IGF-1 alone. Composite application of multiaxial mechanical stimulation plus TGF-β1 and IGF-1 not only triggered the strongest chondrogenesis overall, but also the strongest hypertrophy and osteogenesis.

CONCLUSION

Bioreactor-induced chondrogenic differentiation of human mesenchymal stem cells can be effectively enhanced by growth factor addition, while the partially effective suppression of unwanted signs of endochondral ossification requires further scientific input.

Identification of chondrocyte-binding peptides by phage display

As an initial step toward targeting cartilage tissue for potential therapeutic applications, we sought cartilage-binding peptides using phage display, a powerful technology for selection of peptides that bind to molecules of interest. A library of phage displaying random 12-amino acid peptides was iteratively incubated with cultured chondrocytes to select phage that bind cartilage. The resulting phage clones demonstrated increased affinity to chondrocytes by ELISA, when compared to a wild-type, insertless phage. Furthermore, the selected phage showed little preferential binding to other cell types, including primary skin fibroblast, myocyte and hepatocyte cultures, suggesting a tissue-specific interaction. Immunohistochemical staining revealed that the selected phage bound chondrocytes themselves and the surrounding extracellular matrix. FITC-tagged peptides were synthesized based on the sequence of cartilage-binding phage clones. These peptides, but not a random peptide, bound cultured chondrocytes, and extracelluar matrix. In conclusion, using phage display, we identified peptide sequences that specifically target chondrocytes. We anticipate that such peptides may be coupled to therapeutic molecules to provide targeted treatment for cartilage disorders.

The expression of intronic miRNAs, miR-483 and miR-483*, and their host gene, Igf2, in murine osteoarthritis cartilage

MicroRNAs (miRNAs) have been shown to be important regulators in the pathogenesis of osteoarthritis (OA). The objective of this study was to determine the expression levels of miR-483, miR-483*, their host gene (Igf2) and other cytokines in a murine model of OA. The expression of miR-483 was significantly up-regulated in old mouse and in all of the operation groups, particularly the group assessed 1 week after surgery. The expression of miR-483* was significantly increased in the old mouse group and the group assessed 5 weeks after surgery. The expression of miR-483 was negatively correlated with the expression of (mRNA) Bmp7 and TgfB and positively correlated with Mmp13 by Pearson correlation analysis, while miR-483* was positively correlated with Il1B. Surprisingly, there was no correlation between the expression of either miR-483 or miR-483* and Igf2. This study shows that the expression of miR-483 and miR-483* is up-regulated in murine OA. These data suggest that miR-483 and miR-483* may play critical roles in early and later pathogenesis of OA, respectively, without the involvement of their host gene Igf2.

Acid ceramidase maintains the chondrogenic phenotype of expanded primary chondrocytes and improves the chondrogenic differentiation of bone marrow-derived mesenchymal stem cells

Acid ceramidase is required to maintain the metabolic balance of several important bioactive lipids, including ceramide, sphingosine and sphingosine-1-phosphate. Here we show that addition of recombinant acid ceramidase (rAC) to primary chondrocyte culture media maintained low levels of ceramide and led to elevated sphingosine by 48 hours. Surprisingly, after three weeks of expansion the chondrogenic phenotype of these cells also was markedly improved, as assessed by a combination of histochemical staining (Alcian Blue and Safranin-O), western blotting (e.g., Sox9, aggrecan, collagen 2A1), and/or qPCR. The same effects were evident in rat, equine and human cells, and were observed in monolayer and 3-D cultures. rAC also reduced the number of apoptotic cells in some culture conditions, contributing to overall improved cell quality. In addition to these effects on primary chondrocytes, when rAC was added to freshly harvested rat, equine or feline bone marrow cultures an ∼2-fold enrichment of mesenchymal stem cells (MSCs) was observed by one week. rAC also improved the chondrogenic differentiation of MSCs, as revealed by histochemical and immunostaining. These latter effects were synergistic with TGF-beta1. Based on these results we propose that rAC could be used to improve the outcome of cell-based cartilage repair by maintaining the quality of the expanded cells, and also might be useful in vivo to induce endogenous cartilage repair in combination with other techniques. The results also suggest that short-term changes in sphingolipid metabolism may lead to longer-term effects on the chondrogenic phenotype.

The inflammatory circuitry of miR-149 as a pathological mechanism in osteoarthritis

Osteoarthritis (OA) is a multifactorial degenerative pathology, whose progression is exacerbated by pro-inflammatory cytokines signaling. Among the changes triggered in chondrocytes during inflammation, modified expression of tiny epigenetic regulators as microRNAs was shown having deleterious implications for articular cartilage. Aim of the present study was to identify differentially expressed microRNAs in human OA cartilage and to determine their relevance to pathological progression. An OA model based on inflammatory stimulation of a chondrocytic human cell line was used to analyze microRNAs deregulation, and results revealed miR-149 severely down-regulated by IL1β and TNFα. Real-time PCR analysis of miR-149 was exerted also in human primary chondrocytes isolated from cartilage of OA donors and postmortem from subjects with no known history of OA, confirming down-regulation in osteoarthritis. Moving on a functional study, miR-149 regulatory effect on tumor necrosis factor alpha (TNFα), interleukin 1 beta (IL1β) and interleukin 6 (IL6) 3'UTRs was evaluated by luciferase assays, and chondrocytes production of TNFα upon miR-149 transfection was measured by enzyme-linked immuno sorbent assay. We found that miR-149 is down-regulated in OA chondrocytes, and this decrease seems to be correlated to increased expression of pro-inflammatory cytokines such as TNFα, IL1β and IL6. OA is a multifactorial disease and we think that our results give new insights for understanding the complex mechanisms of osteoarthritic pathogenesis.

Evidence of chondrocyte turnover in lung cartilage, with the probable participation of nestin-positive cells

Healthy adult cartilage is thought to have little or no capacity to renewal, and cell turnover has not been reported in lung cartilage. We report that chondrocyte turnover occurs in lung cartilage, found in an unrelated study. Lung specimens from CD1 mice of 2, 6, 12, 18 or 24 months were fixed in 10% neutral-buffered formalin and paraffin-embedded. Apoptosis was analysed by in situ end-labelling of fragmented DNA. Proliferating cell nuclear antigen (PCNA) and nestin were examined by immunohistochemistry. Apoptosis and PCNA were detected in lung chondrocytes. Serial section analysis showed that cells in apoptosis were different from PCNA-positive cells, indicating that turnover was occurring. Chondrocytes were negative for nestin. Nestin-positive cells were present in connective tissue associated with cartilage, in some specimens in close proximity of it and in perivascular cells. Thus cell turnover in lung cartilage is possible, which may be mediated by nestin-positive cells.

The identification of CD163 expressing phagocytic chondrocytes in joint cartilage and its novel scavenger role in cartilage degradation

Background

Cartilage degradation is a typical characteristic of arthritis. This study examined whether there was a subset of phagocytic chondrocytes that expressed the specific macrophage marker, CD163, and investigated their role in cartilage degradation.

Methods

Cartilage from the knee and temporomandibular joints of Sprague-Dawley rats was harvested. Cartilage degradation was experimentally-induced in rat temporomandibular joints, using published biomechanical dental methods. The expression levels of CD163 and inflammatory factors within cartilage, and the ability of CD163⁺ chondrocytes to conduct phagocytosis were investigated. Cartilage from the knees of patients with osteoarthritis and normal cartilage from knee amputations was also investigated.

Results

In the experimentally-induced degrading cartilage from temporomandibular joints, phagocytes were capable of engulfing neighboring apoptotic and necrotic cells, and the levels of CD163, TNF-α and MMPs were all increased (P<0.05). However, the levels of ACP-1, NO and ROS, which relate to cellular digestion capability were unchanged (P>0.05). CD163⁺ chondrocytes were found in the cartilage mid-zone of temporomandibular joints and knee from healthy, three-week old rats. Furthermore, an increased number of CD163⁺ chondrocytes with enhanced phagocytic activity were present in Col-II⁺ chondrocytes isolated from the degraded cartilage of temporomandibular joints in the eight-week experimental group compared with their age-matched controls. Increased number with enhanced phagocytic activity of CD163⁺ chondrocytes were also found in isolated Col-II⁺ chondrocytes stimulated with TNF-α (P<0.05). Mid-zone distribution of CD163⁺ cells accompanied with increased expression of CD163 and TNF-α were further confirmed in the isolated Col-II⁺ chondrocytes from the knee cartilage of human patients with osteoarthritis, in contrast to the controls (both P<0.05).

Conclusions

An increased number of CD163⁺ chondrocytes with enhanced phagocytic activity were discovered within degraded joint cartilage, indicating a role in eliminating degraded tissues. Targeting these cells provides a new strategy for the treatment of arthritis.

Standardized butanol fraction of WIN-34B suppresses cartilage destruction via inhibited production of matrix metalloproteinase and inflammatory mediator in osteoarthritis human cartilage explants culture and chondrocytes

Background

WIN-34B is a novel Oriental medicine, which represents the n-butanol fraction prepared from dried flowers of Lonicera japonica Thunb and dried roots of Anemarrhena asphodeloides BUNGE. The component herb of WIN-34B is used for arthritis treatment in East Asian countries. The aim of this study was to determine the cartilage-protective effects and mechanisms of WIN-34B and its major phenolic compounds, chlorogenic acid and mangiferin, in osteoarthritis (OA) human cartilage explants culture and chondrocytes.

Methods

The investigation focused on whether WIN-34B and its standard compounds protected cartilage in interleukin (IL)-1β-stimulated cartilage explants culture and chondrocytes derived from OA patients. Also, the mechanisms of WIN-34B on matrix metalloproteinases (MMPs), tissue inhibitor of matrix metalloproteinases (TIMPs), inflammatory mediators, and mitogen-activated protein kinases (MAPKs) pathways were assessed.

Results

WIN-34B was not cytotoxic to cultured cartilage explants or chondrocytes. WIN-34B dose-dependently inhibited the release of glycosaminoglycan and type II collagen, increased the mRNA expression of aggrecan and type II collagen, and recovered the intensity of proteoglycan and collagen by histological analysis in IL-1β-stimulated human cartilage explants culture. The cartilage protective effect of WIN-34B was similar to or better than that of chlorogenic acid and mangiferin. Compared to chlorogenic acid and mangiferin, WIN-34B displayed equal or greater decreases in the levels of MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5, and markedly up-regulated TIMP-1 and TIMP-3. WIN-34B inhibited inflammatory mediators involved in cartilage destruction, such as prostaglandin E2, nitric oxide, tumor necrosis factor-alpha, and IL-1β. The phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase (JNK), and p38 was significantly reduced by WIN-34B treatment, while phosphorylation of JNK was only inhibited by chlorogenic acid or mangiferin in IL-1β-stimulated chondrocytes.

Conclusions

WIN-34B is potentially valuable as a treatment for OA by virtue of its suppression of MMPs, ADAMTSs, and inflammatory mediators, and it’s up-regulation of TIMP-1 and TIMP-3 involved in the MAPK pathway.

Treatment of growth plate injury using IGF-I-loaded PLGA scaffolds

Growth plate fracture can lead to retarded growth and unequal limb length, which may have a lifelong effect on a person's physical stature. The goal of this research was to develop an in vivo tissue-engineering approach for the treatment of growth plate injury via localized delivery of insulin-like growth factor I (IGF-I) from cell-free poly(lactic-co-glycolic acid) (PLGA) scaffolds. Mass loss and drug release studies were conducted to study the scaffold degradation and IGF-I release patterns. In vitro cell studies showed that rat bone marrow stromal cells seeded on the porous scaffolds colonized the pores and deposited matrix within the scaffolds. These in vitro evaluations were followed by a proof-of-concept animal study involving implantation of scaffolds in proximal tibial growth plate defects in New Zealand white rabbits. Histological analysis of tissue sections from the in vivo studies showed regeneration of cartilage, albeit with disorganized structure, at the site of implantation of IGF-I-releasing scaffolds; in contrast, only bone was formed in empty defects and those treated with IGF-free scaffolds. The present findings show the potential for treating growth plate injury using in vivo tissue engineering techniques.

Infrared fiber optic probe evaluation of degenerative cartilage correlates to histological grading

BACKGROUND

Osteoarthritis (OA), a degenerative cartilage disease, results in alterations of the chemical and structural properties of tissue. Arthroscopic evaluation of full-depth tissue composition is limited and would require tissue harvesting, which is inappropriate in daily routine. Fourier transform infrared (FT-IR) spectroscopy is a modality based on molecular vibrations of matrix components that can be used in conjunction with fiber optics to acquire quantitative compositional data from the cartilage matrix.

PURPOSE

To develop a model based on infrared spectra of articular cartilage to predict the histological Mankin score as an indicator of tissue quality.

STUDY DESIGN

Comparative laboratory study.

METHODS

Infrared fiber optic probe (IFOP) spectra were collected from nearly normal and more degraded regions of tibial plateau articular cartilage harvested during knee arthroplasty (N = 61). Each region was graded using a modified Mankin score. A multivariate partial least squares algorithm using second-derivative spectra was developed to predict the histological modified Mankin score.

RESULTS

The partial least squares model derived from IFOP spectra predicted the modified Mankin score with a prediction error of approximately 1.4, which resulted in approximately 72% of the Mankin-scored tissues being predicted correctly and 96% being predicted within 1 grade of their true score.

CONCLUSION

These data demonstrate that IFOP spectral parameters correlate with histological tissue grade and can be used to provide information on tissue composition.

CLINICAL RELEVANCE

Infrared fiber optic probe studies have significant potential for the evaluation of cartilage tissue quality without the need for tissue harvest. Combined with arthroscopy, IFOP analysis could facilitate the definition of tissue margins in debridement procedures.

Single impact cartilage trauma and TNF-α: interactive effects do not increase early cell death and indicate the need for bi-/multidirectional therapeutic approaches

Blunt trauma of articular cartilage, often resulting from accidents or sports injuries, is associated with local inflammatory reactions and represents a major risk factor for development of post-traumatic osteoarthritis. TNF-α is increased in synovial fluid early after trauma, potentiates injury-induced proteoglycan degradation and may act proapoptotic under permissive conditions. We asked whether TNF-α also influences chondrocyte death, gene expression of catabolic and anabolic markers and the release of proinflammatory mediators in the early post-traumatic phase. Interactive effects of a defined single impact trauma (0.59 J) and TNF-α (100 ng/ml) on human early-stage osteoarthritic cartilage were investigated in vitro over 24 h. Exposure of traumatized cartilage to TNF-α did not increase chondrocyte death. IL-6-synthesis was augmented by trauma, TNF-α and combined treatment. The impact increased the release of PGE2 and PGD2 in the presence and absence of TNF-α to a similar extent while TNF-α alone showed no effect. In contrast, NOS2A-expression and nitric oxide (NO)-release were not affected by trauma but significantly increased by TNF-α. Expression of OPG and RANKL was not affected by TNF-α but modulated by trauma. TNF-α with and without trauma significantly induced MMP1 gene expression. These results indicate that TNF-α does not potentiate early cell death in early-stage osteoarthritic cartilage after blunt injury. However, trauma and TNF-α showed independent and interactive effects concerning prostaglandin and NO release. TNF-α probably contributes to cartilage degradation after trauma by an early induction of MMP1 gene expression. Our study confirms that an anti-TNF-α therapy may have inhibitory effects on catabolic and, partly, on inflammatory processes after a single impact trauma. As TNF-α does not contribute to the loss of chondrocytes in the initial post-traumatic phase, a combination with pharmaco-therapeutic strategies reducing early cell death could be reasonable.

Biochemical and proteomic characterization of alkaptonuric chondrocytes

Alkaptonuria (AKU) is a rare genetic disease associated with the accumulation of homogentisic acid (HGA) and its oxidized/polymerized products which leads to the deposition of melanin-like pigments (ochronosis) in connective tissues. Although numerous case reports have described ochronosis in joints, little is known on the molecular mechanisms leading to such a phenomenon. For this reason, we characterized biochemically chondrocytes isolated from the ochronotic cartilage of AKU patients. Based on the macroscopic appearance of the ochronotic cartilage, two sub-populations were identified: cells coming from the black portion of the cartilage were referred to as “black” AKU chondrocytes, while those coming from the white portion were referred to as “white” AKU chondrocytes. Notably, both AKU chondrocytic types were characterized by increased apoptosis, NO release, and levels of pro-inflammatory cytokines. Transmission electron microscopy also revealed that intracellular ochronotic pigment deposition was common to both “white” and “black” AKU cells. We then undertook a proteomic and redox-proteomic analysis of AKU chondrocytes which revealed profound alterations in the levels of proteins involved in cell defence, protein folding, and cell organization. An increased post-translational oxidation of proteins, which also involved high molecular weight protein aggregates, was found to be particularly relevant in “black” AKU chondrocytes. J. Cell. Physiol. 227: 3333–3343, 2012. © 2011 Wiley Periodicals, Inc.

Dietary polyphenols and mechanisms of osteoarthritis

Osteoarthritis is a condition caused in part by injury, loss of cartilage structure and function, and an imbalance in inflammatory and anti-inflammatory pathways. It primarily affects the articular cartilage and subchondral bone of synovial joints and results in joint failure, leading to pain upon weight bearing including walking and standing. There is no cure for osteoarthritis, as it is very difficult to restore the cartilage once it is destroyed. The goals of treatment are to relieve pain, maintain or improve joint mobility, increase the strength of the joints and minimize the disabling effects of the disease. Recent studies have shown an association between dietary polyphenols and the prevention of osteoarthritis-related musculoskeletal inflammation. This review discusses the effects of commonly consumed polyphenols, including curcumin, epigallocatechin gallate and green tea extract, resveratrol, nobiletin and citrus fruits, pomegranate, as well as genistein and soy protein, on osteoarthritis with an emphasis on molecular antiosteoarthritic mechanisms.

Use of complementary and alternative therapy among patients with rheumatoid arthritis and osteoarthritis

AIMS AND OBJECTIVES

We wanted to assess the prevalence of complementary and alternative therapy use among patients suffering from rheumatoid arthritis or osteoarthritis in the Lebanese population and to determine the perceived efficacy and side effects of complementary and alternative therapy in the treatment of these diseases.

BACKGROUND

Complementary and alternative therapy has become popular among patients with chronic illnesses because of its widespread use. Rheumatoid arthritis and osteoarthritis are two diseases associated with severe pain, inflammation and limited activity. Although both are quite common in Lebanon, no studies were conducted in our country to portray complementary and alternative therapy use in their treatment.

DESIGN

Descriptive cross-sectional study.

METHODS

Conducted individualised questionnaire-based interviews among 250 adult patients, ranging between the ages of 20-90 years and diagnosed with either rheumatoid arthritis or osteoarthritis. The questionnaire included demographic information, clinical information, use of conventional therapies and complementary and alternative therapy, and the disease status before and after complementary and alternative therapy use.

RESULTS

Fifty-eight (23·2%) patients used complementary and alternative therapy in addition to their conventional medications in the treatment of either rheumatoid arthritis or osteoarthritis. Most herbal medicine users (63·8%) believed that complementary and alternative therapy was beneficial. The disease status measured by the intensity of pain, sleeping pattern and level of activities was significantly improved after using complementary and alternative therapy (p =0·01). Forty-eight (82·75%) patients were using herbals as complementary and alternative therapy, 14 (24·1%) of whom have sought medical care because of potential concomitant drug-complementary and alternative therapy side effects. However, these side effects were not serious and reversible.

CONCLUSION AND RECOMMENDATIONS

Although complementary and alternative therapy might have beneficial effects in rheumatoid arthritis and osteoarthritis, patients should be cautious about their use and should necessarily inform their health care providers about the consumption of any products other than their conventional medicines.

RELEVANCE TO CLINICAL PRACTICE

It is quite essential for health care professionals to be knowledgeable about the use of complementary and alternative medicine therapies when providing medical care to patients with arthritis.

Dynamic compression of rabbit adipose-derived stem cells transfected with insulin-like growth factor 1 in chitosan/gelatin scaffolds induces chondrogenesis and matrix biosynthesis

Articular cartilage is routinely subjected to mechanical forces and growth factors. Adipose-derived stem cells (ASCs) are multi-potent adult stem cells and capable of chondrogenesis. In the present study, we investigated the comparative and interactive effects of dynamic compression and insulin-like growth factor-I (IGF-I) on the chondrogenesis of rabbit ASCs in chitosan/gelatin scaffolds. Rabbit ASCs with or without a plasmid overexpressing of human IGF-1 were cultured in chitosan/gelatin scaffolds for 2 days, then subjected to cyclic compression with 5% strain and 1 Hz for 4 h per day for seven consecutive days. Dynamic compression induced chondrogenesis of rabbit ASCs by activating calcium signaling pathways and up-regulating the expression of Sox-9. Dynamic compression plus IGF-1 overexpression up-regulated expression of chondrocyte-specific extracellular matrix genes including type II collagen, Sox-9, and aggrecan with no effect on type X collagen expression. Furthermore, dynamic compression and IGF-1 expression promoted cellular proliferation and the deposition of proteoglycan and collagen. Intracellular calcium ion concentration and peak currents of Ca(2+) ion channels were consistent with chondrocytes. The tissue-engineered cartilage from this process had excellent mechanical properties. When applied together, the effects achieved by the two stimuli (dynamic compression and IGF-1) were greater than those achieved by either stimulus alone. Our results suggest that dynamic compression combined with IGF-1 overexpression might benefit articular cartilage tissue engineering in cartilage regeneration.

One-Year Clinical and Radiological Results of a Prospective, Investigator-Initiated Trial Examining a Novel, Purely Autologous 3-Dimensional Autologous Chondrocyte Transplantation Product in the Knee

BACKGROUND

The 3-dimensional autologous chondrocyte transplantation (ACT3D) comprises isolation of chondrocytes from cartilage biopsies, cultivation to spheroids, and transplantation into the cartilage defect.

OBJECTIVES

To evaluate the patients' general health and functionality and to assess the defect repair after ACT3D with spheroids by MRI and MOCART scoring.

METHODS

Thirty-seven patients with isolated chondral lesions of the knee underwent ACT3D with spheroids through medial arthrotomy. Patient-administered scores were assessed at baseline (day before transplantation), at 6 weeks, and at 3, 6, and 12 months. MRI and MOCART scoring were performed at 3 and 12 months after ACT3D.

RESULTS

Patients were diagnosed with full-thickness patellofemoral (n = 16), femoral condylar (n = 18), or both defect types (n = 3), International Cartilage Repair Society (ICRS) grade 3 or 4, with defect sizes between 1.0 and 12.0 cm(2). On average, 59.5 spheroids/cm(2) in defect size were transplanted. An overall statistically significant improvement from baseline to 12 months was observed for all assessment scores (Lysholm, International Knee Documentation Committee [IKDC], SF-36, Tegner) combined with a significant reduction in the visual analog scale (VAS) for pain and an advanced defect filling. Subgroup analyses revealed a positive clinical outcome independent on defect size, defect locations, spheroid dosage, age, duration of symptoms, and severity of complaints at baseline. Seven patients experienced in total 8 adverse events, of which knee joint effusion and blocking were assessed as possibly or probably related to ACT3D.

CONCLUSIONS

The patient-administered assessment scores along with the fast defect filling with ACT3D using spheroids demonstrated an increase in activity level and quality of life after a 1-year follow-up.

BACTERIAL CELLULOSE: A NATURAL NANOMATERIAL FOR BIOMEDICAL APPLICATIONS

Bacterial cellulose (BC) synthesized from Acetobacter xylinum has drawn lots of attention and interest from biomedical device field due to its unique structure and properties. Characterized by its remarkable physical strength and extremely hydrophilic surface, BC has become a favorable material for wound healing, neuron protection, and vascular grafts. Moreover, due to its homologous structure with native extracellular matrix, BC nanofibrous matrix could also be a potent candidate for tissue-engineered scaffolding materials. In this review, the characters and properties of BC, as a promising material for regenerative medicine, are summarized. The progresses made on application of BC to wound dressing, vascular grafts, meniscus and cartilage repair, bone healing, and other biomedical fields are expatiated in details. In the end, the future expectation of BC is briefly discussed. Overall, this low cost, biocompatible, and versatile nanomaterial could eventually be developed as an excellent platform for a new generation of medical device and regenerative medicine.