Photobiomodulation inhibits the expression of chondroitin sulfate proteoglycans after spinal cord injury via the Sox9 pathway

Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins such as chondroitin sulfate proteoglycans inside and around the glial scar is known to affect axonal growth and be a major obstacle to autogenous repair.These proteins are thus candidate targets for spinal cord injury therapy.Our previous studies demonstrated that 810 nm photo biomodulation inhibited the formation of chondroitin sulfate proteoglycans after spinal cord injury and greatly improved motor function in model animals.However,the specific mechanism and potential targets involved remain to be clarified.In this study,to investigate the therapeutic effect of photo biomodulation,we established a mouse model of spinal cord injury by T9 clamping and irradiated the injury site at a power density of 50 mW/cm~2 for 50 minutes once a day for 7 consecutive days.We found that photobiomodulation greatly restored motor function in mice and down regulated chondroitin sulfate proteoglycan expression in the injured spinal cord.Bioinformatics analysis revealed that photobiomodulation inhibited the expression of proteoglycan-related genes induced by spinal cord injury,and versican,a type of proteoglycan,was one of the most markedly changed molecules.Immunofluorescence staining showed that after spinal cord injury,versican was present in astrocytes in spinal cord tissue.The expression of versican in primary astrocytes cultured in vitro increased after inflammation induction,whereas photobiomodulation inhibited the expression of ve rsican.Furthermore,we found that the increased levels of p-Smad3,p-P38 and p-Erk in inflammatory astrocytes were reduced after photobiomodulation treatment and after delivery of inhibitors including FR 180204,(E)-SIS3,and SB 202190.This suggests that Sma d 3/Sox9 and MAP K/Sox9 pathways may be involved in the effects of photobiomodulation.In summary,our findings show that photobiomodulation modulates the expression of chondroitin sulfate proteoglycans,and versican is one of the key target molecules of photo biomodulation.MAPK/Sox9 and Smad3/Sox9 pathways may play a role in the effects of photo biomodulation on chondroitin sulfate proteoglycan accumulation after spinal cord injury.

Physicochemical, structural characterization, and antioxidant activities of chondroitin sulfate from Oreochromis niloticus bones

In this study,chondroitin sulfate was extracted from Oreochromis niloticus bones(OCS)and isolated to three fractions(OCS-1,OCS-2,and OCS-3).The physicochemical properties and structure characterization including monosaccharide,disaccharide compositions,molecular weight(Mw)of OCS were determined by HPAEC,HPLC-SAX,HPGPC,FT-IR spectra,and 1D/2D NMR.Moreover,their thermal properties,crystalline structure,and microstructure were also analyzed.Results showed that their Mw were between 10 kDa and 50 kDa.CS-6 was the predominant disaccharide unit in four OCS,and the CS-4/CS-6 ratios were close to CS from shark cartilage.Besides,the results of antioxidant activity showed that different fractions of OCS had a distinct DPPH radical,hydroxyl radical,and ABTS+radical scavenging activity.OCS-1 has the highest scavenging activities in DPPH and hydroxyl radical compared with other fractions,which showed a higher medicinal value.Those findings may lay some theoretical basis for the potential application development of OCS.

Optimization of the Formulation Process of Glucosamine Chondroitin Sulfate Tablets

[Objectives]This study was conducted to optimize the Formulation Process of glucosamine chondroitin sulfate tablets. [Methods] The orthogonal design with three levels was carried out with microcrystalline cellulose, calcium hydrophosphate and cross-linked polyvinylpyrrolidone as three factors to optimize the preparation process. [Results] When microcrystalline cellulose 200 mg/tablet, calcium hydrophosphate 150 mg/tablet, and cross-linked polyvinylpyrrolidone 80 mg/tablet were added, the angle of repose could meet the requirements of tablet pressing, and the dissolution could reach more than 95% in 30 min. The results of the orthogonal test showed that the dissolution effect of self-made tablets was faster than that of commercial products. [Conclusions] The glucosamine hydrochloride chondroitin sulfate tablets prepared by this prescription have better quality.

Chondroitin sulfate and glucosamine combination in patients with knee and hip osteoarthritis:A long-term observational study in Russia

BACKGROUND Oral treatment of glucosamine(GA) combined with chondroitin sulfate(CS) was reportedly effective for pain relief and function improvement in osteoarthritis patients with moderate to severe knee pain in clinical trials. While the effectiveness of GA and CS on both clinical and radiological findings has been demonstrated, only a few high-quality trials exist. Therefore, controversy regarding their effectiveness in real-world clinical practice remains.AIM To investigate the impact of GA + CS on clinical outcomes of patients with knee and hip osteoarthritis in routine clinical practice.METHODS A multicenter prospective observational cohort study included 1102 patients of both genders with knee or hip osteoarthritis(Kellgren & Lawrence grades Ⅰ-Ⅲ) in 51 clinical centers in the Russian Federation from November 20, 2017, to March 20,2020, who had started to receive oral capsules of glucosamine hydrochloride 500 mg and CS 400mg according to the approved patient information leaflet starting from 3 capsules daily for 3 wk,followed by a reduced dosage of 2 capsules daily before study inclusion(minimal recommended treatment duration is 3-6 mo). Changes in subscale scores [Pain, Symptoms, Function, and Quality of Life(QOL)] of the Knee Injury and Osteoarthritis Outcome Score(KOOS)/Hip Disability and Osteoarthritis Outcome Score(HOOS) questionnaires during the observational period(up to 54-64wk with a total of 4 visits). Patients’ treatment satisfaction, data on the combined oral use of glucosamine hydrochloride and CS, concomitant use of non-steroidal anti-inflammatory drugs(NSAIDs), and adverse events(AEs) were also evaluated.RESULTS A total of 1102 patients with knee and hip osteoarthritis were included in the study. The mean patient age was 60.4 years, most patients were women(87.8%), and their average body mass index was 29.49 kg/m2. All subscale scores(Pain, Symptoms, Function, and QOL) of the KOOS and HOOS demonstrated clinically and statistically significant improvements. In patients with knee osteoarthritis, the mean score increases from baseline to the end of Week 64 were 22.87, 20.78,16.60, and 24.87 on Pain, Symptoms, Physical Function(KOOS-PS), and QOL subscales(P < 0.001for all), respectively. In patients with hip osteoarthritis, the mean score increases were 22.81, 19.93,18.77, and 22.71 on Pain, Symptoms, Physical Function(HOOS-PS), and QOL subscales(P < 0.001for all), respectively. The number of patients using any NSAIDs decreased from 43.1% to 13.5%(P < 0.001) at the end of the observation period. Treatment-related AEs occurred in 2.8% of the patients and mainly included gastrointestinal disorders [25 AEs in 24(2.2%) patients]. Most patients(78.1%) were satisfied with the treatment.CONCLUSION Long-term oral GA + CS was associated with decreased pain, reduced concomitant NSAID therapy, improved joint function and QOL in patients with knee and hip osteoarthritis in routine clinical practice.

M1-type microglia can induce astrocytes to deposit chondroitin sulfate proteoglycan after spinal cord injury

After spinal cord injury(SCI),astrocytes gradually migrate to and surround the lesion,depositing chondroitin sulfate proteoglycan-rich extracellular matrix and forming astrocytic scar,which limits the spread of inflammation but hinders axon regeneration.Meanwhile,microglia gradually accumulate at the lesion border to form microglial scar and can polarize to generate a pro-inflammatory M1 phenotype or an anti-inflammatory M2 phenotype.However,the effect of microglia polarization on astrocytes is unclear.Here,we found that both microglia(CX3 CR1^(+))and astrocytes(GFAP^(+))gathered at the lesion border at 14 days post-injury(dpi).The microglia accumulated along the inner border of and in direct contact with the astrocytes.M1-type microglia(i NOS^(+)CX3 CR1^(+))were primarily observed at 3 and 7 dpi,while M2-type microglia(Arg1^(+)CX3 CR1^(+))were present at larger numbers at 7 and 14 dpi.Transforming growth factor-β1(TGFβ1)was highly expressed in M1 microglia in vitro,consistent with strong expression of TGFβ1 by microglia in vivo at 3 and 7 dpi,when they primarily exhibited an M1 phenotype.Furthermore,conditioned media from M1-type microglia induced astrocytes to secrete chondroitin sulfate proteoglycan in vitro.This effect was eliminated by knocking down sex-determining region Y-box 9(SOX9)in astrocytes and could not be reversed by treatment with TGFβ1.Taken together,our results suggest that microglia undergo M1 polarization and express high levels of TGFβ1 at 3 and 7 dpi,and that M1-type microglia induce astrocytes to deposit chondroitin sulfate proteoglycan via the TGFβ1/SOX9 pathway.The study was approved by the Institutional Animal Care and Use Committee of Anhui Medical University,China(approval No.LLSC20160052)on March 1,2016.

Chondroitin sulfate-mediated albumin corona nanoparticles for the treatment of breast cancer

Chondroitin sulfate-mediated albumin corona nanoparticles were readily prepared without any chemical reaction,and their active tumor targeting and therapeutic effects were examined.Negatively charged chondroitin sulfate(CS)and positively charged doxorubicin(DOX)self-assembled into nanoparticles(CS-DOX-NPs)via electrostatic interactions.Bovine serum albumin(BSA)was then adsorbed on the surface of CS-DOX-NPs to form albumin corona nanoparticles(BC-DOX-NPs)protected from endogenous proteins.Due to the dual effect of BSA and CS,BC-DOX-NPs interacted with the gp60,SPARC and CD44 receptors on tumor cells,facilitating their rapid and efficient transcytosis and improving their accumulation and uptake within tumor tissues.The simultaneous presence of BSA and CS also allowed BC-DOX-NPs to target CD44 efficiently,leading to greater cellular uptake and cytotoxicity against 4 T1 cells than CS-DOX-NPs or free DOX.Intravenous injection of BCDOX-NPs into orthotopic 4 T1 tumor-bearing mice led to greater drug accumulation at the tumor site than with CS-DOX-NPs or free DOX,resulting in significant inhibition of tumor growth and lower exposure of major organs to the drug.

Role of chondroitin sulfate proteoglycan signaling in regulating neuroinflammation following spinal cord injury

Spinal cord injury （SCI） elicits a robust inflammatory response that is a hallmark of the secondary injury mechanisms. Neuroinflammation is orchestrated initially by the response of resident astrocytes and microglia to injury, which subsequently facilitates the recruitment of peripheral immune cells into the SCI lesion （Orr and Gensel, 2018）. This inflammatory response contributes to cell death and tissue degeneration through the production of pro-inflammatory cytokines and chemokines, free radicals and proteolytic enzymes. However, neuroinflammatory cells also play beneficial regulatory role in repair mechanisms after SCI by adopting a reparative and wound healing phenotype （Orr and Gensel, 2018; Tran et al., 2018）. Hence, understanding the underlying mechanisms by which immune cells are reg- ulated within the microenvironment of injury would aid in harnessing the reparative potential of inflammation following SCI.

Effect of chondroitin sulfate proteoglycans on neuronal cell adhesion, spreading and neurite growth in culture

As one major component of extracellular matrix （ECM） in the central nervous system, chondroitin sul- fate proteoglycans （CSPGs） have long been known as inhibitors enriched in the glial scar that prevent axon regeneration after injury. Although many studies have shown that CSPGs inhibited neurite out- growth in vitro using different types of neurons, the mechanism by which CSPGs inhibit axonal growth remains poorly understood. Using cerebellar granule neuron （CGN） culture, in this study, we evaluated the effects of different concentrations of both immobilized and soluble CSPGs on neuronal growth, in- cluding cell adhesion, spreading and neurite growth. Neurite length decreased while CSPGs concentration arised, meanwhile, a decrease in cell density accompanied by an increase in cell aggregates formation was observed. Soluble CSPGs also showed an inhibition on neurite outgrowth, but it required a higher concen- tration to induce cell aggregates formation than coated CSPGs. We also found that growth cone size was significantly reduced on CSPGs and neuronal cell spreading was restrained by CSPGs, attributing to an inhibition on lamellipodial extension. The effect of CSPGs on neuron adhesion was further evidenced by interference reflection microscopy （IRM） which directly demonstrated that both CGNs and cerebral cortical neurons were more loosely adherent to a CSPG substrate. These data demonstrate that CSPGs have an effect on cell adhesion and spreading in addition to neurite outgrowth.

Effects of chondroitin sulfate on alteration of actin cytoskeleton in rats with acute necrotizing pancreatitis

BACKGROUND: In experimental acute pancreatitis, a large amount of reactive oxygen species are produced, and in turn cytoskeletal changes may be induced in pancreatic tissue. These changes contribute to an imbalance of digestive enzyme segregation, transport, exocytosis and activation, resulting in cell injury. In this study, we assessed the effects of chondroitin sulfate (CS) on attenuation of oxidative damage and protection of F-actin in rats with acute necrotizing pancreatitis (ANP). METHODS: Ninety male Wistar rats were divided randomly into three groups. Group A was infused with 5% sodium taurocholate; group B was treated with CS; and group C served as control. Rats from the three groups were killed at 1, 3 or 8 hours. The levels were measured of malonyl dialdehyde (MDA), total superoxide dismutase (SOD), glutathione synthetase (GSH), serum amylase (SAM) and adenosine triphosphate (ATP). F-actin immunostained with rhodamine-phalloidin was analyzed using a confocal laser scanning system and the content of F-actin protein was determined. RESULTS: The levels of SAM increased in groups A and B, whereas the levels of GSH, SOD and ATP in group A decreased markedly during pancreatitis, and MDA increased significantly. The levels of GSH, SOD and ATP in group B were higher than those in group A, but the level of MDA was lower than in group A. At the same time, ANP resulted in early disruption of the cytoskeleton with dramatic changes and a loss of F-actin. Administration of CS moderated the damage to the actin cytoskeleton. CONCLUSIONS: Retrograde infusion of sodium taurocholate via the pancreatic duct may produce pancreatic necrosis and a marked increase in serum amylase activity, induce a severe depletion of ATP level, prime lipid peroxidation, and damage F-actin. Treatment with CS can ameliorate pancreatic cell conditions, limit cell membrane peroxidation, protect F-actin, and attenuate pancreatitis.

Preparation and Characterization of PD LIA/Chondroitin Sulfate/Chitosan Seaffold for Peripheral Nerve Regeneration

A novel bioactive and bioresorbable PDLLA/chondroitin sulfate/chitosan scaffold was prepared via layer-by-layer（LBL） electrostatic-self-assembly （ESA） and the thermally induced phase separation （TIPS） technique. Chondroitin sulfate and chitosan were alternately deposited on the activated PDLLA substrate. The deposition process was monitored by UV-Vis absorbance spectroscopy. After frozen and lyophilized, the scaffold was characterized by attenuated total reflection （ATR）-FT-IR, XPS, SEM and AFM. The results showed that the scaffold was modified uniformly with a dense inner layer with few detectable pores and a porous sponge outer layer with the pore size about 5 μm, there was an obvious across section and the average thickness of each layer was about 9.4 nm.

Preparation and Charactcrization of a Novel PDLLA/Chondroitin Sulfate/Chitosan Asymmetry Film

A novel bioactive and bioresorbable asymmetry film was prepared. The PDLLA membrane was activated by 1, 6-hexanediamine to obtain a stable positive charge surface. Chondroitin sulfate and chitosan were then deposited on activated PDLLA membrane via layer-by-layer （LBL） electro-static assembly （ESA） technique. The deposition process was monitored by UV-Vis absorbance spectroscopy. The composite membrane was frozen lyophilized to form the asymmetry film and characterized by attenuated total reflectic （ATR）-FT-IR, XPS and SEM. The experimental results show that a stable 1, 6-hexanediamine layer on PDLLA substrate based on the aminolysis of the polyester and the layer thickness increase linearly first with the increase of the deposited layers, and then increases slowly due to the layer interpenetration. The test results of ATR-FT- IR and SEM show the asymmetry film is modified uniformly with a dense inner layer and a porous sponge outer tayer.

Partial Hydrolysis of the Fucosylated Chondroitin Sulfate from Sea Cucumber Isostichopus badionotus and Its Mechanism

The method for preparing low molecular weight fucosylated chondroitin sulfate from sea cucumber lsostichopus badionotus using partial acid hydrolysis was reported, and its hydrolysis mechanism was also investigated. The sea cucumber chondroitin sulfate FCS was hydrolyzed under different conditions （80℃3 h and 6 h）, then isolated and purified on a Bio-P-4 geltration to prepare low molecular weight fractions （LMWF-FCS）. The chemical compositions of LMWF-FCS showed the branched fucose （Fuc） was cleaved during acid hydrolysis process, whereas the mole ratio of acetyl-galactosamine （GalNAc） and glucuronic acid （GlcA） in the backbone remained the same, which indicated the backbone was a typical chondroitin sulfate structure. The disaccharide composition analysis of LMWF-FCS suggested that the sulfation patterns of GalNAc in the backbone chain changed and the substitution value was reduced. Furthermore, the 1D NMR analysis illustrated the branched-Fuc was cleaved during acid hydrolysis, but their substitution patterns were not influenced, which was distinct from the previous reports that the substitutions of branched-Fuc in FCS were easy to change. Simultaneously, the sulfation pattern of GalNAc in backbone chain changed obviously in the acid hydrolysis process. The anticoagulant activity in vitro illuminated the anticoagulant activity of the degradation products over time in the acid hydrolysis are gradually declined, but still kept good. Therefore, the LMWF-FCS prepared could be developed as a new anticoagulant and antithrombotic drug like low molecular weight heparin.

The relevance study of effective information between near infrared spectroscopy and chondroitin sulfate in ethanol precipitation process

Near infrared spectroscopy(NIRS)is based on molecular overtone and combination vibrations.It is difficult to assign specific features under complicated system.So it is necessary to find the relevance between NIRS and target compound.For this purpose,the chondroitin sulfate(CS)ethanol precipitation process was selected as the research model,and 90 samples of 5 different batches were collected and the content of CS was determined by modifed carbazole method.The relevance between NIRS and CS was studied throughout optical pathlength,pretreat ment methods and variables selection methods.In conclusion,the first derivative with Savitzky--Golay(SG)smoothing was selected as the best pretreatment,and the best spectral region was selected using interval partial least squares(iPLS)method under 1 mm optical cell.A multivariate cali-bration model was established using PLS algorithm for determining the content of CS,and the root mean square error of prediction(RMSEP)is 3.934gL-1.This method will have great potential in process analytical technology in the future.

Semi-synthetic chondroitin sulfate CS-semi5 upregulates miR-122-5p,conferring a therapeutic effect on osteoarthritis via the p38/MMP13 pathway

Osteoarthritis(OA)is an aging-associated disease characterized by joint stiffness pain and destroyed articular cartilage.Traditional treatments for OA are limited to alleviating various OA symptoms.There is a lack of drugs available in clinical practice that can truly repair cartilage damage.Here,we developed the chondroitin sulfate analog CS-semi5,semi-synthesized from chondroitin sulfate A.In vivo,CS-semi5 alleviated inflammation,provided analgesic effects,and protected cartilage in the modified Hulth OA rat model and papain-induced OA rat model.A bioinformatics analysis was performed on samples from OA patients and an exosome analysis on papain-induced OA rats,revealing miR-122-5p as the key regulator associated with CS-semi5 in OA treatment.Binding prediction revealed that miR-122-5p acted on the 30-untranslated region of p38 mitogen-activated protein kinase,which was related to MMP13 regulation.Subsequent in vitro experiments revealed that CS-semi5 effectively reduced cartilage degeneration and maintained matrix homeostasis by inhibiting matrix breakdown through the miR-122-5p/p38/MMP13 axis,which was further validated in the articular cartilage of OA rats.This is the first study to investigate the semi-synthesized chondroitin sulfate CS-semi5,revealing its cartilageprotecting,anti-inflammatory,and analgesic properties that show promising therapeutic effects in OA via the miR-122-5p/p38/MMP13 pathway.

Full-thickness osteochondral defect repair using a biodegradable bilayered scaffold of porous zinc and chondroitin sulfate hydrogel

The regeneration of osteochondral tissue necessitates the re-establishment of a gradient owing to the unique characteristics and healing potential of the chondral and osseous phases.As the self-healing capacity of hyaline cartilage is limited,timely mechanical support during neo-cartilage formation is crucial to achieving optimal repair efficacy.In this study,we devised a biodegradable bilayered scaffold,comprising chondroitin sulfate(CS)hydrogel to regenerate chondral tissue and a porous pure zinc(Zn)scaffold for regeneration of the underlying bone as mechanical support for the cartilage layer.The photocured CS hydrogel possessed a compressive strength of 82 kPa,while the porous pure Zn scaffold exhibited a yield strength of 11 MPa and a stiffness of 0.8 GPa.Such mechanical properties are similar to values reported for cancellous bone.In vitro biological experiments demonstrated that the bilayered scaffold displayed favorable cytocompatibility and promoted chondrogenic and osteogenic differentiation of bone marrow stem cells.Upon implantation,the scaffold facilitated the simultaneous regeneration of bone and cartilage tissue in a porcine model,resulting in(i)a smoother cartilage surface,(ii)more hyaline-like cartilage,and(iii)a superior integration into the adjacent host tissue.Our bilayered scaffold exhibits significant potential for clinical application in osteochondral regeneration.

Reactive oxygen species-scavenging nanoparticles coated with chondroitin sulfate protect cartilage against osteoarthritis in vivo

Osteoarthritis(OA)is a prevalent chronic inflammatory disease in joints.Current interventions confront systemic toxicity and insufficient bioavailability.The unbalanced microenvironment of OA joints mainly fosters over-expressed reactive oxygen species(ROS),extracellular matrix disintegration,and apoptosis of chondrocytes.In this study,a kind of ROS-scavenging,biodegradable and drug-free nanoparticles(PP NPs)were constructed by the crosslinking of poly(propylene fumarate)(PPF)and ROS-scavenging poly(thioketal)(PTK).The high content of PTK and high crosslinking density of PPF and PTK innovatively endowed the NPs with slow degradation and prolonged ROS-elimination ability.The NPs were further surface-modified with chondroitin sulfate(CS),one of the dietary supplements for osteoarthritis.The intrinsic properties of resultant PP-CS NPs were excavated in vitro and in vivo.The PP-CS NPs could desirably consume 1,10-diphenyl-2-picrylhydrazyl(DPPH)radicals without toxicity to RAW264.7 cells in vitro.With an average diameter of~300 nm,the PP-CS NPs could be intra-articular administrated in OA rats and showed prolonged joint retention time,allowing only one injection per month.Moreover,the PP-CS NPs possessed a prolonged ROS depletion and M2 macrophage induction effect,down-regulated inflammatory cytokines,and reduced glycosaminoglycans loss.Consequently,the PP-CS NPs protected articular surface erosion,inhibited uneven cartilage matrix,and attenuated OA progression.

A rapid method for extraction,purification and structure analysis of chondroitin sulfate from six marine tissues

This study was designed to establish a strategy for the extraction,purification,and structure analysis of chondroitin sulfate(cs)in milligram amounts.Crude acidic polysaccharides were extracted from six kinds of marine animals by enzymatic hydrolysis and hexadecylpyridinium chloride precipitation and purified by Q Sepharose Fast Flow strong anion exchange column.The purification of each crude polysaccharide was completed within 1 h.The structure of the polysaccharides,i.e.their chemical characterization,functional group,molecular weight and monosaccharide composition,were analyzed by colorimetry,nuclear magnetic resonace and high-performance liquid chromatogrpahy,respectively.All polysaccharides were identified as Cs.The oligosaccharide profile produced by enzyme hydrolysis of polysaccharides was determined by strong anion-exchange high-performance liquid chromatorgraphy.This method can be widely applied to the extraction and characterization of chondroitin sulfate from unknown raw materials,screening high-quality sources of functional polysaccharides,and laying a good foundation for thefollowing studyof the structure-function relationshipof polysaccharides.

Reveal crucial subtype of natural chondroitin sulfate on the functionalized coatings for cardiovascular implants

Surface functionalization is generally accepted as one of the most useful methods for endowing better biocompatibility of the cardiovascular implants. Chondroitin sulfate(CS) is a commercial drug applied for preventing cardiovascular diseases in clinics, suggesting a potential application for functionalized coatings. Our previous work demonstrated that the CS conjugated onto the poly-dopamine(PDA)/hexanediamine(HD) co-deposited 316 L stainless steel(316 L SS) could endow the surface stronger multi-functions for cardiovascular implants. However, the natural CS has two subtypes, CS A and CS C,while it is still unclear which subtype makes more contribution to the surface modification of cardiovascular implants. Thus, the present study focus on comparing CS A and CS C via preparing functionalized coatings on the cardiovascular implants. Our data suggested PDA/HD-CS C coating possessed better blood compatibility and pro-endothelialization function through controlling the phenotype and distribution of macrophages, smooth muscle cells and endothelial cells in time sequence and space sequence.

Novel nano-microspheres containing chitosan, hyaluronic acid, and chondroitin sulfate deliver growth and differentiation factor-5 plasmid for osteoarthritis gene therapy

Objective:To construct a novel non-viral vector loaded with growth and differentiation factor-5(GDF-5) plasmid using chitosan,hyaluronic acid,and chondroitin sulfate for osteoarthritis (OA)gene therapy.Methods: Nano-microspheres (NMPs)were prepared by mixing chitosan,hyaluronic acid,and chondreitin sulfate.GDF-5 plasmid was encapsulated in the NMPs through electrostatic adsorption.The basic characteristics of the NMPs were observed,and then they were co-cultured with chondrocytes to observe their effects on extracellular matrix (ECM) protein expression.Finally,NMPs loaded with GDF-5were inje.cted into the articular cavities of rabbits to observe their therapeutic effects on OA in vivo.Results:NMPs exhibited good physicochemical properties and low cytotoxicity.Their average diameter was (0.61±0.20)μm,and encapsulation efficiency was (38.19±0.36)%.According to Cell Counting Kit-8(CCK-8)assay,relative cell viability was 75%-99%when the total weight of NMPs was less than 560μg. Transfection efficiency was (62.0±2.1)% in a liposome group,and (60.0±1.8)% in the NMP group.There was no sig- nificant difference between the two groups (P>0.05).Immunohistochemical staining results suggested that NMPs can successfully transfect chondrocytes and stimulate ECM protein expression in vitro.Compared with the control groups, the NMP group significantly promoted the expression of chondrocyte ECM in vivo (P<0.05),as shown by analysis of the biochemical composition of chondrocyte ECM.When NMPs were injected into OA model rabbits,the expression of ECM proteins in chondrocytes was significantly promoted and the progression of OA was slowed down.Conclusions: Based on these data,we think that these NMPs with excellent physicochemical and biological properties could be promising non-viral vectors for OA gene therapy.

A Novel Polybrene/Chondroitin Sulfate C Double Coated Capillary and Its Application in Capillary Electrophoresis

A new capillary coated by double polymer, polybrene/chondroitin sulfate C (P/CC), was developed using a simple procedure. The P/CC double coated capillary showed long lifetime, strong chemical stability and good reproducibility. It endured during more than 100 replicated analyses and was also tolerant to HCl (1 mol/L), NaOH (0.01 mol/L), CH3OH and CH3CN. The P/CC double coated capillary can be applied to basic drug analyses. The adsorption of basic drugs to the capillary wall was suppressed and the peak tailing greatly decreased. The use of the P/CC double coated capillary allowed excellent separation of the enantiomers of some basic drugs by using chondroitin sulfate C as the chiral selector, and the peak symmetry of basic drugs was further improved under these conditions.