OBJECTIVES: To design and prepare silk fibroin/hyaluronic acid composite hydrogel. METHODS: The thiol modified silk fibroin and the double-bond modified hyaluronic acid were rapidly cured into gels through thiol-ene click polymerization under ultraviolet light condition. The grafting rate of modified silk fibroin and hyaluronic acid was characterized by ¹H NMR spectroscopy; the gel point and the internal microstructure of hydrogels were characterized by rheological test and scanning electron microscopy; the mechanical properties were characterized by compression test; the swelling rate and degradation rate were determined by mass method. The hydrogel was co-cultured with the cells, the cytotoxicity was measured by the lactate dehydrogenase method, the cell adhesion was measured by the float count method, and the cell growth and differentiation on the surface of the gel were observed by scanning electron microscope and fluorescence microscope. RESULTS: The functional group substitution degrees of modified silk fibroin and hyaluronic acid were 17.99% and 48.03%, respectively. The prepared silk fibroin/hyaluronic acid composite hydrogel had a gel point of 40-60 s and had a porous structure inside the gel. The compressive strength was as high as 450 kPa and it would not break after ten cycles. The water absorption capacity of the composite hydrogel was 4-10 times of its own weight. Degradation experiments showed that the hydrogel was biodegradable, and the degradation rate reached 28%-42% after 35 d. The cell biology experiments showed that the cytotoxicity of the composite gel was low, the cell adhesion was good, and the growth and differentiation of the cells on the surface of the gel were good. CONCLUSIONS The photocurable silk fibroin/hyaluronic acid composite hydrogel can form a gel quickly, and has excellent mechanical properties, adjustable swelling rate and degradation degree, good biocompatibility, so it has promising application prospects in biomedicine.
Fibroins/chemistry* ; Hydrogels/chemistry* ; Hyaluronic Acid/chemistry* ; Biocompatible Materials/chemistry* ; Click Chemistry ; Sulfhydryl Compounds ; Silk/chemistry*

Soft tissue is an indispensable tissue in human body. It plays an important role in protecting the body from external physical, chemical or biological factors. Mild soft tissue injuries can self-heal, while severe soft tissue injuries may require related treatment. Natural polymers (such as chitosan, hyaluronic acid, and collagen) and synthetic polymers (such as polyethylene glycol and polylactic acid) exhibit good biocompatibility, biodegradability and low toxicity. It can be used for soft tissue repairs for antibacterial, hemostatic and wound healing purposes. Their related properties can be enhanced through modification or preparation of composite materials. Commonly used soft tissue repairs include wound dressings, biological patches, medical tissue adhesives, and tissue engineering scaffolds. This study introduces the properties, mechanisms of action and applications of various soft tissue repair medical materials, including chitosan, hyaluronic acid, collagen, polyethylene glycol and polylactic acid, and provides an outlook on the application prospects of soft tissue repair medical materials and products.
Humans ; Biocompatible Materials/chemistry* ; Chitosan/chemistry* ; Hyaluronic Acid ; Tissue Scaffolds/chemistry* ; Collagen/chemistry* ; Polymers/chemistry* ; Polyethylene Glycols ; Soft Tissue Injuries

In this study, insulin (insulin, INS)/Ca₃PO₄ complex and glucose oxidase (glucose oxidase, GOx)/Cu₃(PO₄)₂ complex were prepared by coprecipitation method. The mineralized insulin (mineralized insulin, m-INS) showed irregular crystalline clusters, and the mineralized glucose oxidase (m-GOx) showed flower spherical morphology, with a diameter of about 1-2 μm. In vitro simulated release experiment showed that m-INS released INS as the pH value of the medium decreased. When the pH value was 4.5, the release amount reached 96.68%. The enzyme activity detection experiment showed that the enzyme activity stability of m-GOx was higher than that of free GOx. It still maintained high activity after 10 days at room temperature, while the activity of GOx was less than 60%. The glucose solution was prepared to simulate the state of normal blood glucose (5.6 mmol/L) and hyperglycemia (22.2 mmol/L). When m-INS and m-GOx were added to the glucose solution, the release amount of INS showed a significant glucose concentration dependence. The higher the glucose concentration, the greater the release amount and release rate of INS. Finally, m-INS, m-GOx and hyaluronic acid (HA) solution were mixed to prepare HA microneedle arrays loaded with m-INS and m-GOx. Type 1 diabetes mice were constructed to evaluate the effect of drug-loaded HA microarray on blood glucose control in diabetic rats. The results show that the HA microneedles loaded with m-INS/m-GOx could deliver drugs effectively. The average blood glucose concentration in diabetic rats dropped to about 7 mmol/L within 1 h, normal blood glucose concentration could be maintained for 10 h, and the overall blood glucose concentration was lower than the level before administration for 36 hours. Compared with HA microneedles loaded with INS only, m-ins microneedles showed better glucose tolerance, longer-lasting glucose control effect and less risk of hypoglycemia. Compared with other sustained-release systems, the preparation process of the core components in this study is simple, efficient, safe and effective, and has great commercial potential.
Animals ; Blood Glucose ; Delayed-Action Preparations/therapeutic use* ; Diabetes Mellitus, Experimental/drug therapy* ; Drug Delivery Systems/methods* ; Glucose Oxidase/chemistry* ; Hyaluronic Acid ; I Blood-Group System ; Insulin/therapeutic use* ; Mice ; P Blood-Group System ; Rats

According to literature, certain microorganism productions mediate biological effects. However, their beneficial characteristics remain unclear. Nowadays, scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine. The present review aims to introduce microorganism-derived biological macromolecules, such as pullulan, alginate, dextran, curdlan, and hyaluronic acid, and their available sources for tissue engineering. Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications. These natural-based materials are attractive in pharmaceutical, regenerative medicine, and biomedical applications. This study provides a detailed overview of natural-based biomaterials, their chemical and physical properties, and new directions for future research and therapeutic applications.
Biocompatible Materials/chemistry* ; Humans ; Hyaluronic Acid ; Regenerative Medicine ; Tissue Engineering ; Tissue Scaffolds/chemistry*

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 chondroitin 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-5 were injected 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 560 μg. Transfection efficiency was (62.0±2.1)% in a liposome group, and (60.0±1.8)% in the NMP group. There was no significant 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.
Animals ; Cell Differentiation ; Cell Survival/drug effects* ; Chitosan/chemistry* ; Chondrocytes/cytology* ; Chondroitin Sulfates/chemistry* ; Drug Carriers ; Extracellular Matrix/metabolism* ; Genetic Therapy/methods* ; Growth Differentiation Factor 5/genetics* ; Hyaluronic Acid/chemistry* ; Microspheres ; Nanomedicine ; Osteoarthritis/therapy* ; Plasmids/metabolism* ; Rabbits

OBJECTIVETo provide a theoretical basis for surface modification of titanium implants, the effects of the stiffness of polyelectrolyte multilayer films on titanium surface on bacterium adhesion was explored.

METHODSVia layer-by-layer technique, catechol functionalized polyelectrolyte multilayer film (cPEM) was constructed on titanium surface by using catechol functionalized hyaluronic acid (cHA) and lipopolysaccharide-amine nanopolymersomes (NP). The stiffness of cPEM was controlled by adjusting the catechol substitution degree of cHA (5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%). Titanium samples covered with cPEM were selected as test group, and the cPEM was constructed with the lowest, medium and highest stiffness. The polished titanium was used as a control. The surface topography of titanium before and after film construction was observed by scanning electron microscopy (SEM). At 1 and 24 h after incubation, the adhesion and clonal formation of Streptococcus mutans (S. mutans) on different titanium surfaces were quantified, and their morphology and survival status were observed by SEM and laser scanning confocal microscope (LSCM).

RESULTSWhen the catechol grafting ratio was 5%, 30% and 70%, the lowest, medium and highest cPEM stiffness were obtained, and the cPEM stiffness were (10.69±4.54) GPa(cPEM-L), (20.99± 5.81) GPa (cPEM-M) and (32.57±6.93) GPa (cPEM-H) respectively, and the stiffness of polished titanium was (107.12±8.68) GPa (P<0.05). SEM observation showed that after cPEM coating, the titanium surface became smoother. After incubation for 1 and 24 h, the amount of adhesion and clonal formation of S. mutans on cPEM were higher than those on control titanium, and the difference was statistically significant (P<0.05). SEM images showed that for 1 h incubation, softer surfaces were beneficial for S. mutans adhering and agglomerating, while this difference nearly disappeared at 24 h. Observation under LSCM revealed that most of bacteria were alive on titanium disks at 1 h, and their amount decreased with the increase of stiffness. At 24 h, the living/dead bacterium ratios on cPEM-L and control titanium was higher than that on cPEM-M and cPEM-H, and cPEM-L surface was dominated by living bacteria, while stiffer cPEM-M and cPEM-H had more dead bacteria than living bacteria.

CONCLUSIONSIncreasing the stiffness of polyelectrolyte films on titanium limits the adhesion of S. mutans. As an independent factor, stiffness influences the bacterium adhesion.

Bacterial Adhesion ; Catechols ; Elasticity ; Hyaluronic Acid ; Lipopolysaccharides ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Nanoparticles ; Polymers ; chemistry ; Streptococcus mutans ; physiology ; Surface Properties ; Time Factors ; Titanium ; chemistry

OBJECTIVETo explore biomimetic mineralization of polyelectrolyte multilayer films (PEM) of gene-loaded lipopolysaccharide-amine nanopolymersomes/hyaluronic acid self assembled on titanium surface.

METHODSVia lay-by-layer self assembly technology, PEM were constructed on titanium or quartz surface using bone morphogenetic protein-2(BMP-2) plasmid-loaded lipopolysaccharide-amine nanopolymersomes(pLNP) as a polycation, and hyaluronic acid(HA) as a polyanion. The constructed PEM were defined as substrate-pLNP-(HA-pLNP)n, where a successive deposition of HA and pLNP on substrate surface was defined as one assembly cycle, and n was the cycle number. Biomimetic mineralization on surfaces of Ti-pLNP-(HA-pLNP)4(Group A, with outermost layer of pLNP), Ti-pLNP-(HA-pLNP)4.5(Group B, with outermost layer of HA), blank control(polished titanium, Ti) and alkaline-heat treated titanium(Ti-OH) were investigated. The biomimetic mineralization was analyzed by observing the topography under field-emisssion electron microscopy(FE-SEM), characterizing the surface chemical structure and components via X-ray diffractometer(XRD) and X-ray energy disperse spectroscopy(EDS).

RESULTSFor experiment groups, XRD analysis showed that the diffraction peak of hydroxyapatite appeared, and its intensity was higher than that for Ti group. FE-SEM images showed that its surface was homogeneously covered by discrete agglomerate of big particles. EDS spectra showed that the percentage of Ca and P were 77.24% and 64.23%, and these were much higher than those in Ti group.

CONCLUSIONSThe surface of Ti-pLNP-(HA-pLNP)n is favorable for in vitro biomimetic mineralization.

Amines ; chemistry ; Biomimetic Materials ; chemistry ; Bone Morphogenetic Protein 2 ; Durapatite ; chemistry ; Hyaluronic Acid ; chemistry ; Lipopolysaccharides ; Nanocomposites ; chemistry ; Plasmids ; Surface Properties ; Titanium ; chemistry

OBJECTIVETo study the inhibitory effect of flavonoids from Glycyrrhiza uralensis on thioacetamide-induced chonic hepatic fibrosis in rats and the effect on the protein expressions of transforming growth factor-β1 (TGF-β1) and Caspase-3 in livers.

METHODMale Sprague-Dawley rats were randomly divided into totally seven groups: the normal control group, the model group, LF groups s (400, 200, 100, 50 mg · kg(-1) · d(-1)) and the silymarin positive control group (30 mg · kg(-1) · d(-1)). The hepatic fibrosis model was induced in the rats through intraperitoneal injection with 3% thioacetamide (TAA) at a dose of 150 mg · kg(-1) body weight twice a week for 12 weeks. During the course, the control group and the model group were orally administered with saline (1 mL · kg(-1) · d(-1)). After the modeling and drug intervention, the pathologic changes and fibrosis in liver tissues were observed by HE staining and Masson's Trichrome staining. The serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and liver hydroxyproline (HYP) contents were assayed by biochemical process. The serum hyaluronic acid (HA) was assessed by radioimmunoassay. In addition, the protein expressions of liver TGF-β1 and Caspase-3 were examined by immunohistochemical method. The mRNA expression of TGF-β1 in hepatic tissues was examined by quantitative Real-time PCR analysis.

RESULTCompared with the model group, flavonoids can protect the integrity of the structure of liver tissues, significantly reduce the hepatic cell degeneration and necrosis and the proliferation of fibrous tissues, notably reduce the serum AST, ALT, ALP and HA and HYP in hepatic tissues and down-regulate the protein expressions of liver TGF-β1 and Caspase-3 and the mRNA expression of TGF-β1 in hepatic tissues.

CONCLUSIONThe licorice flavonoids can resist the thioacetamide-induced hepatic fibrosis in rats. Its mechanism may be related to the down-regulation of the protein expressions of TGF-β1 and Caspase-3.

Animals ; Caspase 3 ; analysis ; Flavonoids ; pharmacology ; Glycyrrhiza uralensis ; chemistry ; Hyaluronic Acid ; blood ; Liver ; pathology ; Liver Cirrhosis, Experimental ; chemically induced ; metabolism ; prevention & control ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Thioacetamide ; Transforming Growth Factor beta1 ; analysis ; genetics

OBJECTIVETo investigate the biocompatibility and degradation rate of crosslinking sodium hyaluronate gel with different ratio of molecular weight, so as to choose the effective, safe and totally degraded hyaluronate gel for aesthetic injection.

METHODS(1) Compound colloid was formed by cross-linking the divinyl sulphone and sodium hyaluronate with different molecular weight (4 x 10(5), 8 x 10(5), 10 x 10(5), 12 x 10(5)). (2) Healthy level KM mice was randomly divided into two groups to receive hyaluronic acid gel or liquid injection. Each group was subdivided into three subgroup to receive hyaluronic acid with different molecular weight. The biocompatibility and degradation rate, of hyaluronate were observed at 7, 90, 180 days after injection. At the same time, different molecular weight of sodium hyaluronate gel is sealed or exposed respectively under the low temperature preservation to observe its natural degradation rate. (3) The most stable colloid was selected as aesthetic injector for volunteers to observe the aesthetic effect.

RESULTSThe sodium hyaluronate gel with molecular of 4 x 10(5) was completely degraded 90 days later. The sodium hyaluronate gel with molecular of 8 x 10(5) was completely degraded 180 days later. The sodium hyaluronate gel with molecular of 10 x 10(5) was degraded to 90.0% after 180 days. The sodium hyaluronate liquid can be degraded completely within 7 days. The colloid could be kept for at least 12 months when sealed under low temperature, but was totally degraded when exposed for I d. Sodium hyaluronate gel with molecular 10 x 10(5) was confirmed to be kept for at least 6 months in animal experiment and clinical trials.

CONCLUSIONSUnder the same condition of material ratio, the higher the molecular weight is, the lower the degradation rate is. But the liquidity of gel is not good for injection when molecular weight is too large. It suggests that Sodium hyaluronate gel with molecular 10 x 10(5) maybe the best choice in cosmetic injections.

Animals ; Cross-Linking Reagents ; administration & dosage ; chemistry ; Hyaluronic Acid ; administration & dosage ; chemistry ; Injections, Subcutaneous ; Mice ; Molecular Weight ; Random Allocation

OBJECTIVETo investigate the effects of Dragon' s blood extract on proliferation and secret extracellular matrix function of fibroblasts in vitro.

METHODSDragon' s blood was extracted by chloroform, acetoacetic ester, alcohol. Human fibroblast were cultured in vitro in media containing gradient dilutions of Dragon' s blood extracts (0.002, 0.02, 0.2, 2, 20 mg/ml) , which was followed by cell proliferation assessed with MTT assay on 0, 12, 24, 36, 48, 60, 72 h. Under the optimal concentration, the cell growth curves were drawn and the flow cytometry (FCM) was used to determine the changes of cell cycle. On 0, 12, 24, 36, 48, 60, 72 h, the concentration of hyaluronic acid in the supernatant of fibroblast culture was measured by radioimmunoassay.

RESULTS0.2-2 mg/ml Dragon' s blood extracts enhanced the proliferation of fibroblasts in a dose-dependent manner. 2 mg/ml was the optimal dilution of Dragon's blood extract, and it increased the ratio of S cells in cell cycle [(25.80 ± 3.10)%] than control group [(7.50 ± 0.70)%, P < 0.01]. From 12 h to 72 h, in 2 mg/ml Dragon's blood group, concentration of Hyaluronic acid secreted by fibroblasts gradually increased, but were less than control (P < 0.01).

CONCLUSIONSDragon's blood acetoacetic ester extract improved the proliferation of cultured human fibroblasts in vitro, might be beneficial to promote wound healing.

Cell Cycle ; Cell Proliferation ; drug effects ; Culture Media ; chemistry ; Dose-Response Relationship, Drug ; Extracellular Matrix ; Fibroblasts ; cytology ; drug effects ; secretion ; Flow Cytometry ; Humans ; Hyaluronic Acid ; analysis ; secretion ; Plant Extracts ; pharmacology ; Resins, Plant ; Time Factors