Development of Injectable Fucoidan and Biological Macromolecules Hybrid Hydrogels for Intra-Articular Delivery of Platelet-Rich Plasma.

Platelet-rich plasma (PRP) is rich in growth factors and has commonly been utilized in the repair and regeneration of damaged articular cartilage. However, the major drawbacks of direct PRP injection are unstable biological fixation and fast or burst release of growth factors. Fucoidan is a heparinoid compound that can bind growth factors to control their release rate. Furthermore, fucoidan can reduce arthritis through suppressing inflammatory responses and thus it has been reported to prevent the progression of osteoarthritis, promote bone regeneration and accelerate healing of cartilage injury. Injectable hydrogels can be used to deliver cells and growth factors for an alternative, less invasive treatment of cartilage defects. In this study, hyaluronic acid (HA) and fucoidan (FD) was blended with gelatin (GLT) and the GLT/HA/FD hybrid was further cross-linked with genipin (GP) to prepare injectable GP-GLT/HA/FD hydrogels. The gelation rate was affected by the GP, GLT, HA and FD concentrations, as well as the pH values. The addition of HA and FD to GLT networks improved the mechanical strength of the hydrogels and facilitated the sustained release of PRP growth factors. The GP-GLT/HA/FD hydrogel showed adequate injectability, shape-persistent property and strong adhesive ability, and was more resistant to enzymatic degradation. The PRP-loaded GP-GLT/HA/FD hydrogel promoted cartilage regeneration in rabbits, which may lead to an advanced PRP therapy for enhancing cartilage repair.

Development of genipin-crosslinked and fucoidan-adsorbed nano-hydroxyapatite/hydroxypropyl chitosan composite scaffolds for bone tissue engineering.

Hydroxypropyl chitosan (HPCS) has recently attracted increasing attention in biomedical applications because it has enhanced water solubility, excellent biocompatibility, and better antioxidant and antibacterial activities compared with chitosan. However, HPCS doesn't meet the mechanical strength requirement in bone tissue engineering and is not suitable for cell adhesion and growth because of its hydrophilic nature and low crystallinity. In this study, nano-scaled hydroxyapatite (n-HA) and HPCS were synthesized, respectively, and then n-HA/HPCS nanocomposite scaffolds were developed by incorporating n-HA into HPCS matrix accompanied with crosslinking of HPCS by a naturally occurring compound, genipin (GP), which in turn greatly altered the hydrophilicity and mechanical properties. The nanocomposite scaffolds showed an open structure with interconnected pores and a rough morphology with n-HA inserted in the GP-crosslinked HPCS matrix. The porosity, swelling capacity, compressive strength, fluorescence emission and degradation rate can be regulated by varying GP concentrations and n-HA contents. An osteoconductive and osteogenic marine algae polysaccharide, fucoidan, was further adsorbed to the composite scaffolds via electrostatic interactions. Incorporation of n-HA and adsorption of FD into the composite scaffolds increased ALP activity in 7F2 osteoblast cells and promoted their mineralization. The FD-adsorbed n-HA/HPCS composite scaffolds can be a potential biomaterial for BTE applications.

Development of mutlifunctional nanoparticles self-assembled from trimethyl chitosan and fucoidan for enhanced oral delivery of insulin.

Oral administration is a highly attractive approach for the delivery of protein drugs. However, oral protein therapeutics typically exhibit extremely poor bioavailability due to the harsh gastrointestinal (GI) environments and low permeability of protein across the intestinal barrier. Trimethyl chitosan (TMC) shows excellent mucoadhesive and absorption-enhancing properties while fucoidan (FD) has hypoglycemic effects and can prevent diabetes-related complications. Here we report, for the first time, that TMC combined with FD can be developed to a mutlifunctional nanoplatform for enhancing the transepithelial permeation of insulin through the intestinal epithelial cell barrier and inhibiting the α-glucosidase activity. TMC and FD self-assembled into spherical nanoparticles (NPs) for insulin encapsulation. TMC/FD NPs protected insulin against degradation by releasing insulin in a pH-dependent manner in the gastrointestinal tract fluids. The NPs were able to modulate the barrier function of the Caco-2 intestinal epithelial cell monolayer, and enhance paracellular transport of insulin across the intestinal barrier. TMC/FD NPs also showed α-glucosidase inhibitory activity, with an inhibition ratio of 33.2% at 2 mg/mL. The superior transepithelial absorption enhancing property of the TMC/FD NPs is expected to combine in the future with the functions of fucoidan against diabetes-related complications for development of advanced mutlifunctional therapeutic platforms for diabetes.

Development of nanocomposite scaffolds based on biomineralization of N,O-carboxymethyl chitosan/fucoidan conjugates for bone tissue engineering.

Bone tissue engineering holds great promise and clinical efficacy for the regeneration of bone defects. In this study, an amphoteric N,O-carboxymethyl chitosan (NOCC) and fucoidan (FD) were covalently cross-linked via an amidation reaction to synthesize NOCC/FD composite hydrogels. The hydrogels were lyophilized and then three-dimensional scaffolds with interconnected macropores were obtained. To enhance the mechanical properties and osteogenic activity, the NOCC/FD scaffolds were biomineralized for the growth of hydroxyapatite crystals. A comparative assessment of the structures, morphologies, and physical properties of the original and mineralized scaffolds were performed by SEM, EDS, X-ray diffraction and FT-IR analysis. FD regulated the growth of hydroxyapatite nanocrystallites (n-HAp) and thus the NOCC/FD scaffolds showed better mineralization efficiency than NOCC scaffolds. The compressive strength of the scaffolds was greatly enhanced after mineralization with n-HAp. The n-HAp/NOCC/FD scaffolds enhanced the proliferation, ALP activity, and mineralization of osteoblast cells more strongly than the original and mineralized NOCC scaffolds. Hence, the n-HAp-mineralized NOCC/FD scaffolds may prove to be an excellent and versatile scaffold for bone tissue engineering.

Mutlifunctional nanoparticles prepared from arginine-modified chitosan and thiolated fucoidan for oral delivery of hydrophobic and hydrophilic drugs.

Self-assembled nanoparticles (NPs) from arginine-modified chitosan (CS-N-Arg) and thiolated fucoidan (THL-fucoidan) were synthesized to enhance the transport of dextran and curcumin across intestinal epithelial cell layer. CS-N-Arg/THL-fucoidan NPs exhibited a pH-sensitive assembly-disassembly and drug release property. Evaluations of the NPs in enhancing the transport of a hydrophilic macromolecule (FITC-dextran) and a hydrophobic drug (curcumin) were investigated in Caco-2 cell monolayers. The cationic CS-N-Arg in the NPs induced disruption of intestinal epithelial tight junctions as indicated by the decrease of transepithelial electrical resistance (TEER). Permeation studies revealed that the NPs enhanced the paracellular permeation of macromolecular dextran through the monolayer barrier. In addition, the multifunctional NPs increased the permeability of rhodamine 123 because the thiomer THL-fucoidan in the NPs inhibited P-glycoprotein. Cellular uptake and permeability of curcumin encapsulated in the NPs were improved due to increasing their water solubility and stability.

Elevated IgM against Nε-(Carboxyethyl)lysine-modified Apolipoprotein A1 peptide 141-147 in Taiwanese with Alzheimer's disease.

OBJECTIVE: Advanced glycation end products (AGEs) are involved in the pathogenesis of Alzheimer's disease (AD). Specific AGEs and related autoantibodies may be early AD markers. Apolipoprotein A1 (ApoA1) and its post-translational modifications (PTMs) are associated with neurodegeneration and thus selected to test the hypothesis. METHODS: Serum samples from totally 64 AD or health control (HC) Taiwanese were analyzed. ApoA1 was isolated from the serum and examined through LC-MS/MS and PTM analyses. A specific AGE and its autoantibodies were determined using Western blotting or ELISA. RESULTS: Nε-(Carboxyethyl)lysine (CEL) modification, a kind of AGEs, was identified on ApoA1 peptide 141-QKVEPLR-147 (ApoA1141-147) from AD serum. Total CEL adducts and autoantibodies against CEL on ApoA1141-147 were significantly increased in AD samples. The area under the receiver operating characteristic curve was 0.965 for anti-CEL-ApoA1141-147 IgM. Mini Mental State Examination scores of the AD patients were positively correlated with anti-CEL-ApoA1141-147 IgM, suggesting that the IgM level is high in early AD pathology and decreased with disease progression. CONCLUSION: CEL modification was increased on AD serum proteins including ApoA1, leading to an elevated anti-CEL IgM in early disease state. Both CEL and anti-CEL IgM may serve as AD biomarkers.

Annexin A2-mediated cancer progression and therapeutic resistance in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a head and neck cancer with poor clinical outcomes and insufficient treatments in Southeast Asian populations. Although concurrent chemoradiotherapy has improved recovery rates of patients, poor overall survival and low efficacy are still critical problems. To improve the therapeutic efficacy, we focused on a tumor-associated protein called Annexin A2 (ANXA2). This review summarizes the mechanisms by which ANXA2 promotes cancer progression (e.g., proliferation, migration, the epithelial-mesenchymal transition, invasion, and cancer stem cell formation) and therapeutic resistance (e.g., radiotherapy, chemotherapy, and immunotherapy). These mechanisms gave us a deeper understanding of the molecular aspects of cancer progression, and further provided us with a great opportunity to overcome therapeutic resistance of NPC and other cancers with high ANXA2 expression by developing this prospective ANXA2-targeted therapy.

Piperlongumine inhibits cancer stem cell properties and regulates multiple malignant phenotypes in oral cancer.

Piperlongumine (PL), a natural product of Piper longum, inhibits multiple malignant phenotypes. Therefore, the present study examined whether PL suppresses cancer stemness in oral cancer. The cellular effects of PL were determined by examining alterations in tumor sphere formation, cell migration, invasion, proliferation ability, chemosensitivity and radiosensitivity. Reverse transcription-quantitative polymerase chain reaction analysis and western blotting were performed in order to determine molecular expression levels. The present study revealed that PL inhibited cancer stem cell-forming ability and suppressed the expression of the stemness-related transcription factors SRY-Box 2, POU class 5 homeobox 1, and Nanog homeobox. However, it increased the expression of the differentiation marker cytokeratin 18. PL also suppressed cell migration and invasion, resulting in the elimination of the epithelial-mesenchymal transition. Furthermore, PL increased chemo- and radiosensitivity and suppressed tumor growth in vitro and in vivo. The results of the present study suggested that PL inhibits malignant phenotypes via the suppression of cancer stemness in oral cancer. Thus, PL may serve as an effective therapeutic agent for oral cancer.

Development of genipin-crosslinked fucoidan/chitosan-N-arginine nanogels for preventing Helicobacter infection.

AIM: This study aims to validate the anti-Helicobacter pylori efficacy of amoxicillin-loaded nanoparticles and nanogels with pH-responsive and site-specific drug release properties against H. pylori infection. MATERIALS & METHODS: Genipin-crosslinked low molecular weight fucoidan/chitosan-N-arginine nanogels (FCSA) were prepared for targeted delivery of amoxicillin to the site of H. pylori infected AGS gastric epithelial cells. RESULTS: The negatively charged nanogels (n-FCSA) adhered to H. pylori and exhibited pH-responsive drug release property to reduce cytotoxic effects in H. pylori infected AGS cells. CONCLUSION: These in vitro findings suggest that n-FCSA nanogels are potential carriers for H. pylori specific delivery of antibacterial agents, and provide the basis for further studies on the clinical use of the nanogels.

Eotaxin-2 increased toll-like receptor 4 expression in endothelial cells in vitro and exacerbates high-cholesterol diet-induced atherogenesis in vivo.

Eotaxin-2 is a potent chemoattractant. High concentration of eotaxin-2 triggers the inflammation and tumor metastasis. Inhibition of eotaxin-2 may protect experimental atherogenesis although the mechanism is still unclear. Toll-like receptor 4 (TLR4) plays a major role mediating vascular inflammation, which is related to atherogenesis. In the results, we demonstrated that eotaxin-2 potentially impairs the tube formation capacity of human coronary artery endothelial cells (HCAECs). Eotaxin-2 augments the monocytic adhesion in lipopolysaccharides (LPS)-induced HCAECs, and which were reversed by TLR4 siRNA. Thus this study was conducted to investigate whether eotaxin-2 increases TLR4 expression, and then enhances the sensitivity of cells to antigen stimulation in HCAECs, which mediates the increasing of the development of serious atherosclerosis. In fact, we showed that JNK/SAPK, p38 MAPK, and ERK1/2 activation contribute to the transcriptional signaling pathway, JNK/SAPK and p38 MAPK regulate post-transcriptional modification, as well as protein-trafficking pathway in eotaxin-2-treated HCAECs TLR4 expression. RNA binding proteins, such as human antigen R (HuR) and tristetraprolin (TTP) mediate stability of TLR4 mRNA and chaperone, such as PRAT4A (a protein associated with TLR4) regulate trafficking of TLR4 protein might confer eotaxin-2 responsiveness. Eotaxin-2 administration led to a significant elevation of high cholesterol diet-induced atherosclerosis, and of TLR4 expression in B6.129S7-Ldlrtm1Her /J but not Ldlr-/--/-/Tlr4-/- mice. Our results revealed that eotaxin-2 induced overexpression TLR4 via mitogen-activated protein kinases (MAPK) signaling pathways, RNA binding proteins-mediated mRNA stabilization, and PRAT4A-regulated trafficking in HCAECs. These effects may lead to amplification of inflammatory responses contribute to the pathogenesis of cardiovascular disorders.

Alterative effects of an oral alginate extract on experimental rabbit osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is a common joint disease that causes disabilities in elderly. However, few agents with high efficacy and low side effects have been developed to treat OA. In this study, we evaluated the effects of the alginate extract named CTX in OA cell and rabbit models. RESULTS: CTX was formulated by hydrolyzing sodium alginate polymers with alginate lyase and then mixing with pectin. HPLC was used to analyze the CTX content. Human chondrosarcoma SW1353 cells treated with interleukin-1ß were used as OA model cells to investigate the effects of CTX on chondrocyte inflammation and anabolism. CTX at concentrations up to 1000 µg/ml exerted low cytotoxicity. It inhibited the gene expression of proinflammatory matrix metalloproteinases (MMPs) including MMP1, MMP3 and MMP13 in a dose-dependent manner and increased the mRNA level of aggrecan, the major proteoglycan in articular cartilage, at 1000 µg/ml. Thirteen-week-old New Zealand White rabbits underwent a surgical anterior cruciate ligament transection and were orally treated with normal saline, glucosamine or CTX for up to 7 weeks. Examinations of the rabbit femur and tibia samples demonstrated that the rabbits taking oral CTX at a dosage of 30 mg/kg/day suffered lesser degrees of articular stiffness and histological cartilage damage than the control rabbits. CONCLUSIONS: The gene expression profiles in the cell and the examinations done on the rabbit cartilage suggest that the alginate extract CTX is a pharmaco-therapeutic agent applicable for OA therapy.

Targeting annexin A2 reduces tumorigenesis and therapeutic resistance of nasopharyngeal carcinoma.

The expression of annexin A2 (ANXA2) in nasopharyngeal carcinoma (NPC) cells induces the immunosuppressive response in dendritic cells; however, the oncogenic effect and clinical significance of ANXA2 have not been fully investigated in NPC cells. Immunohistochemical staining for ANXA2 was performed in 61 patients and the association with clinicopathological status was determined. Short hairpin (sh)RNA knockdown of ANXA2 was used to examine cellular effects of ANXA2, by investigating alterations in cell proliferation, migration, invasion, adhesion, tube-formation assay, and chemo- and radiosensitivity assays were performed. RT-qPCR, Western blotting, and immunofluorescence were applied to determine molecular expression levels. Clinical association studies showed that the expression of ANXA2 was significantly correlated with metastasis (p = 0.0326) and poor survival (p = 0.0256). Silencing of ANXA2 suppressed the abilities of cell proliferation, adhesion, migration, invasion, and vascular formation in NPC cell. ANXA2 up-regulated epithelial-mesenchymal transition associated signal proteins. Moreover, ANXA2 reduced sensitivities to irradiation and chemotherapeutic drugs. These results define ANXA2 as a novel prognostic factor for malignant processes, and it can serve as a molecular target of therapeutic interventions for NPC.

Huntingtin-associated protein 1 interacts with breakpoint cluster region protein to regulate neuronal differentiation.

Alterations in microtubule-dependent trafficking and certain signaling pathways in neuronal cells represent critical pathogenesis in neurodegenerative diseases. Huntingtin (Htt)-associated protein-1 (Hap1) is a brain-enriched protein and plays a key role in the trafficking of neuronal surviving and differentiating cargos. Lack of Hap1 reduces signaling through tropomyosin-related kinases including extracellular signal regulated kinase (ERK), resulting in inhibition of neurite outgrowth, hypothalamic dysfunction and postnatal lethality in mice. To examine how Hap1 is involved in microtubule-dependent trafficking and neuronal differentiation, we performed a proteomic analysis using taxol-precipitated microtubules from Hap1-null and wild-type mouse brains. Breakpoint cluster region protein (Bcr), a Rho GTPase regulator, was identified as a Hap1-interacting partner. Bcr was co-immunoprecipitated with Hap1 from transfected neuro-2a cells and co-localized with Hap1A isoform more in the differentiated than in the nondifferentiated cells. The Bcr downstream effectors, namely ERK and p38, were significantly less activated in Hap1-null than in wild-type mouse hypothalamus. In conclusion, Hap1 interacts with Bcr on microtubules to regulate neuronal differentiation.

Serum level of interleukin-21 is elevated in chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is an inflammatory disease of the sinuses and mucosa with unclear pathogenesis. Interleukin (IL)-21 is mainly expressed in activated cluster of differentiation (CD)4(+) T cells and has potent regulatory effects on the immune system. OBJECTIVE: This study is to determine whether IL-21 in the blood is correlated with CRS. METHODS: The blood samples from CRS patients and normal controls were analyzed in correlation with clinical features. The eosinophil percentage was counted, and serum levels of total immunoglobulin E (IgE) and IL-21 were analyzed by enzyme-linked immunosorbent assay (ELISA). In addition, IL-21 and interferon (IFN)-γ secreted from stimulated peripheral blood mononuclear cells (PBMCs) were measured by ELISA, and their mRNA expression levels were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). Disease severity was scored based on computed tomography (CT) scan, nasal endoscopy, and global osteitis scoring scale (GOSS). RESULTS: A total of 55 CRS and 37 healthy subjects were recruited. The average levels of serum total IgE were 20 kU/L in normal group, 290 kU/L in CRS with nasal polys (CRSwNP), and 187 kU/L in CRS without nasal polys (CRSsNP). IL-21 levels were 28 pg/mL in normal group, 54 pg/mL in CRSwNP, and 71 pg/mL in CRSsNP. Both IgE and IL-21 were significantly elevated in both CRS patient subgroups. However, no significant difference was found between these two patient subgroups. The serum IL-21 levels correlated well with the disease severity in the patients. In addition, the secreted IL-21 was enhanced significantly in the patient's PBMCs stimulated by phytohemagglutin (PHA). CONCLUSION: IL-21 could be a target for diagnosis and treatment of CRS.

Dendritic cells respond to nasopharygeal carcinoma cells through annexin A2-recognizing DC-SIGN.

Dendritic cells (DCs) play an essential role in immunity and are used in cancer immunotherapy. However, these cells can be tuned by tumors with immunosuppressive responses. DC-specific intercellular adhesion molecule 3-Grabbing Nonintegrin (DC-SIGN), a C-type lectin expressed on DCs, recognizes certain carbohydrate structures which can be found on cancer cells. Nasopharyngeal carcinoma (NPC) is an epithelial cell-derived malignant tumor, in which immune response remains unclear. This research is to reveal the molecular link on NPC cells that induces the immunosuppressive responses in DCs. In this article, we report identification of annexin A2 (ANXA2) on NPC cells as a ligand for DC-SIGN on DCs. N-linked mannose-rich glycan on ANXA2 may mediate the interaction. ANXA2 was abundantly expressed in NPC, and knockdown of ANXA2 suppressed NPC xenograft in mice, suggesting a crucial role of ANXA2 in NPC growth. Interaction with NPC cells caused DC-SIGN activation in DCs. Consequently DC maturation and the proinflammatory interleukin (IL)-12 production were inhibited, and the immunosuppressive IL-10 production was promoted. Blockage of either DC-SIGN or ANXA2 eliminated the production of IL-10 from DCs. This report suggests that suppression of ANXA2 at its expression or glycosylation on NPC may improve DC-mediated immunotherapy for the tumor.

Apoptotic toxicity of destruxin B in human non-Hodgkin lymphoma cells.

Destruxins are fungal toxins used as insecticides. Recent reports demonstrated the potential anti-cancer activities of destruxin B (DB). This study is to discover the effects of DB in lymphoma. Flow cytometry and Western blotting were used to analyze apoptosis and protein expression, respectively, in Toledo human non-Hodgkin lymphoma cells in response to DB. Administration of DB, induced apoptosis via death receptor pathway activating Fas associated death domain (FADD), caspase 8 and caspase 3, and suppressed the cell growth. In addition, DB alterated mitochondrial membrane potential by increasing the expressions of tBid and Bax, but decreasing the levels of Bcl-2, resulting in the release of apoptosis-inducing factor (AIF). In conclusion, apoptosis of human non-Hodgkin lymphoma cells in response to DB is induced through the death receptor pathway and involves an alteration of the mitochondrial membrane potential. These findings may aid the development of novel treatment of non-Hodgkin lymphoma.

Injectable hyaluronic-acid-doxycycline hydrogel therapy in experimental rabbit osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is a common joint disease that causes disabilities in elderly adults. However, few long-lasting pharmacotherapeutic agents with low side effects have been developed to treat OA. We evaluated the therapeutic effects of intra-articular injections of hydrogels containing hyaluronic acid (HA) and doxycycline (DOX) in a rabbit OA model. RESULTS: Thirteen week old New Zealand White rabbits undergone a partial meniscectomy and unilateral fibular ligament transection were administered with either normal saline (NT), HA, DOX or HA-DOX hydrogels on day 0, 3, 6, 9 and 12; animals were also examined the pain assessment in every three days. The joint samples were taken at day 14 post-surgery for further histopathological evaluation. The degree of pain was significantly attenuated after day 7 post-treatment with both HA and HA-DOX hydrogels. In macroscopic appearance, HA-DOX hydrogel group showed a smoother cartilage surface, no or minimal signs of ulceration, smaller osteophytes, and less fissure formation in compare to HA or DOX treatment alone. In the areas with slight OA changes, HA-DOX hydrogel group exhibited normal distribution of chondrocytes, indicating the existence of cartilage regeneration. In addition, HA-DOX hydrogels also ameliorated the progression of OA by protecting the injury of articular cartilage layer and restoring the elastoviscosity. CONCLUSION: Overall, from both macroscopic and microscopic data of this study indicate the injectable HA-DOX hydrogels presented as a long-lasting pharmacotherapeutic agent to apply for OA therapy.

Hyaluronan regulates PPARγ and inflammatory responses in IL-1ß-stimulated human chondrosarcoma cells, a model for osteoarthritis.

The carbohydrate polymer, hyaluronan, is a major component of the extracellular matrix in animal tissues. Exogenous hyaluronan has been used to treat osteoarthritis (OA), a degenerative joint disease involving inflammatory changes. The underlying mechanisms of hyaluronan in OA are not fully understood. Pro-inflammatory interleukin (IL)-1ß downregulates peroxisome proliferator-activated receptor gamma (PPARγ), and increases expression of matrix metalloproteinases (MMPs) which are responsible for the degeneration of articular cartilage. The effects of low- and high-molecular-weight hyaluronan (oligo-HA and HMW-HA) on the inflammatory genes were determined in human SW-1353 chondrosarcoma cells. HMW-HA antagonized the effects of IL-1ß by increasing PPARγ and decreasing cyclooxygenase (COX)-2, MMP-1, and MMP-13 levels. It promoted Akt, but suppressed mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NFκB) signaling, indicating anti-inflammatory effects. In contrast, the cells had overall opposite responses to oligo-HA. In conclusion, HMW-HA and oligo-HA exerted differential inflammatory responses via PPARγ in IL-1ß-treated chondrosarcoma cells.

Incorporation of exudates of human platelet-rich fibrin gel in biodegradable fibrin scaffolds for tissue engineering of cartilage.

The goal of this study was to assess the incorporation of exudates of human platelet-rich fibrin (hPRF) that is abundant in platelet cytokines and growth factors into biodegradable fibrin (FB) scaffolds as a regeneration matrix for promoting chondrocyte proliferation and re-differentiation. hPRF was obtained from human blood by centrifugation without an anticoagulant, and the exudate of hPRF was collected and mixed with bovine fibrinogen, and then thrombin was added to form the FB scaffold. Proliferation and differentiation of human primary chondrocytes and a human chondrosarcoma cell line, the SW-1353, embedded in the three-dimensional (3D) scaffolds and on the two-dimensional (2D) surface of the FB scaffolds so produced were evaluated in comparison with an agarose (AG) scaffold serving as the control. Results demonstrated that the amounts of these cytokines and growth factors in hPRF exudates were higher than those in the blood-derived products except for TGF-ß1. Chondrocytes and SW1353 cells on the 2D and 3D FB scaffolds with the addition of the exudates of PRF exhibited more-available proliferation and differentiation than cells on 2D and 3D FB and AG scaffolds. It was concluded that FB scaffolds can provide an appropriate environment for chondrocyte proliferation and re-differentiation, and it could be improved by adding exudates of hPRF. These 3D scaffolds have great promise for cartilage tissue engineering.

Bone and joint protection ability of ceramic material with biological effects.

Ceramic materials with biological effects (bioceramic) have been found to modulate various biological effects, especially those effects involved in antioxidant activity and hydrogen peroxide scavenging. As arthropathy and osteopathy are the major chronic diseases of geriatric medicine, we explored the possible activity of bioceramic on these conditions using animal and cell models. Rabbits received intra-articular injections of lipopolysaccharides (LPS) to induce inflammation that mimic rheumatic arthritis. FDG isotopes were then IV injected for PET scan examinations at 16 hours and 7 days after the LPS injection. We examined and compared the bioceramic and control groups to see if bioceramic was capable of relieving inflammation in the joints by subtracting the final and initial uptake amount of FDG (max SUV). We studied the effects in prostaglandin E2 (PGE2) inhibition on the human chondrosarcoma (SW1353) cell line, and the effects on the murine osteoblast (MC3T3-E1) cell line under oxidative stress. All the subtractions between final and initial uptakes of FDG in the left knee joints of the rabbits after LPS injection indicated larger decreases in the bioceramic group than in the control group. This anti-arthritic or inflammatory effect was also demonstrated by the PGE2 inhibition of the SW1353 cells. We further proved that bioceramic treatment of the MC3T3-E1 cells resulted in increased viability of osteoblast cells challenged with hydrogen peroxide toxicity, and increased alkaline phosphatase activity and the total protein production of MC3T3-E1 cells under oxidative stress. Since LPS-induced arthritis is an experimental model that mimics RA, the potential therapeutic effects of bioceramic on arthropathy merit discussion. Bioceramic may contribute to relieving inflammatory arthritis and maintaining bone health.