Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capacity of non-pepsinyzed type VI collagen to bind to hyaluronan was investigated. Type VI collagen was extracted from bovine meniscal cartilage with 6 M GuHCl and purified by extraction of PEG precipitates and dissociative Sephacryl S-500 HR chromatography. Type VI collagen, detected with a monoclonal antibody, bound in 0.5 M NaCl to hyaluronan-coated micro-wells, the degree of binding being higher at 37 degrees C than 23 degrees C and 4 degrees C. Incubation of type VI collagen in competitive inhibition assays with testicular hyaluronidase digests of hyaluronan in liquid phase, reduced binding of the protein to hyaluronan-coated microwells to background levels. Thus, non-pepsinyzed type VI collagen binds to hyaluronan in vitro.
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PMID:Interaction of intact type VI collagen with hyaluronan. 175 55

An investigation was made of the inter-relationships and characteristics of various hyaluronidase forms isolated from ram spermatozoa. They were shown to be members of an oligomeric series, apparently formed by intermolecular disulphide cross-linking. Two monomer species were detected, alpha (Mr 89,600) and beta (Mr 81,200). Although the alpha species predominated, the two were evenly distributed throughout the oligomer population, and they shared antigenic determinants; the beta species did not arise from the alpha species as a result of catabolism following cell disruption. The oligomeric series was of the form [Hyal]n, where n = 1, 2, 4, 5, 6, 7 etc.; no trimer was detectable. Though essentially cationic, part of the hyaluronidase population also had anionic characteristics, probably due to oxidation of free thiol groups. In the anionic subpopulation tetramers and higher oligomers predominated, whereas the non-anionic subpopulation was composed of monomers, dimers and tetramers. The pH optimum of the monomer was 4.3 in 0.2 M-NaCl/0.1 M-sodium citrate, whereas that of the anionic oligomers was 4.9. Both serum albumin and polylysine stimulated enzyme activity at pH 4.0 in the absence of NaCl; polylysine was particularly effective. NaCl diminished the stimulatory effects, and essentially suppressed them above the pH optimum. The specific activities of different oligomer populations were the same as that of the monomer, and conversion of oligomers into monomer by reduction had likewise no effect upon the specific activity. Low concentrations of poly(vinyl alcohol), poly(ethylene glycol) or polyvinylpyrrolidone stabilized soluble hyaluronidase activity by preventing the enzyme's binding to surfaces; solutions of anionic oligomers were further stabilized by NaCl. Enzyme preparations were stable for several months frozen in the presence of poly(vinyl alcohol) and salt.
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PMID:Preliminary characterization of the multiple forms of ram sperm hyaluronidase. 342 27

To study the contribution of tissue components to the mechanical properties of veins, pressure-volume relationships were obtained with the cylindrical segments of isolated dog external jugular veins at several levels of longitudinal extension. At each length, the transmural pressure of the segment was raised up to 20 cmH2O and then reduced to 0 cmH2O by increasing and decreasing the intraluminal volume at a constant rate. The longitudinal extension of the venous segments caused a significant reduction in the incremental volume elasticity within the pressure range of 0-2 cmH2O (E0-2) as well as a significant increase of the incremental volume elasticity within 10-20 cmH2O (E10-20). The pressure-volume relationships of venous segments were also constructed in the same way after treatment with 1 mg/ml collagenase for 30 min, 0.1 mg/ml elastase for 5 min, or 1 mg/ml hyaluronidase for 60 min. Treatment with collagenase or elastase produced a significant increase of the E0-2. The treatment, however, caused no effect on E10-20. Treatment with hyaluronidase induced no effect on these mechanical parameters but produced a significant attenuation of the extension-induced decrease in E0-2. Activation of the venous smooth muscles induced by norepinephrine (10(-4) M) or high-potassium Krebs solution caused a significant decrease of E0-2 as well as a significant increase of E10-20. A complete relaxation of the smooth muscles elicited by Ca(2+)-free Krebs solution containing ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (2 mM) caused an increase of E0-2. Mechanical rubbing of the endothelium caused no significant effect on E0-2 and E10-20.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of collagenase, elastase, and hyaluronidase on mechanical properties of isolated dog jugular veins. 834 43

A new hyaluronic acid (HA)-based hydrogel film was prepared and evaluated for use in drug delivery. This biocompatible material crosslinks and gels in minutes, and the dried film swells and rehydrates to a flexible hydrogel in seconds. HA was first converted to the adipic dihydrazide derivative and then crosslinked with the macromolecular homobifunctional reagent poly(ethylene glycol)-propiondialdehyde to give a polymer network. After gelation, a solvent casting method was used to obtain a HA hydrogel film. The dried film swelled sevenfold in volume in buffer, reaching equilibrium in less than 100 s. Scanning electron microscopy (SEM) of the hydrogel films showed a condensed and featureless structure before swelling, but a porous microstructure when hydrated. The thermal behavior of the hydrogel films was characterized by differential scanning calorimetry. The enzymatic degradation of the HA hydrogel films by hyaluronidase was studied using both SEM and a spectrophotometric assay. Drug release from the hydrogel film was evaluated in vitro using selected anti-bacterial and anti-inflammatory drugs. This novel biomaterial can be employed for controlled release of therapeutic agents at wound sites.
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PMID:Cross-linked hyaluronic acid hydrogel films: new biomaterials for drug delivery. 1101 55

The objective of this work was to develop an effective vitrification technique for cryopreserving oocytes in sheep ovarian tissues. Ovaries were surgically recovered from 15 pubertal ewes and the ovarian cortex was cut into sections. Ovarian tissues were placed in equilibration medium consisting of 4% (v/v) ethylene glycol (EG) and 20% (v/v) FBS in TCM-199 on ice for 30 min and transferred to vitrification solution (35% EG, 5% polyvinylpyrrolidone, 0.4M trehalose and 20% FBS in TCM-199) for 5 min. Ovarian tissues were vitrified by dropping the tissue on the surface of a steel cube cooled by liquid nitrogen. Cumulus-enclosed oocyte complexes (COC) were also collected and vitrified following the procedure used for ovarian tissues. After 2-3 weeks of storage in liquid nitrogen, ovarian tissues and COC were thawed at 37 degrees C in 0.3M trehalose and COC in ovarian tissues were mechanically and enzymatically isolated. Vitrified COC and freshly collected COC were washed twice in maturation medium (TCM-199 supplemented with 0.255 mM pyruvate and 10% heat-treated estrus cow serum) and cultured in 50 microl drops of maturation medium under paraffin oil for 23-25h at 39 degrees C in a humidified atmosphere of 5% CO(2) in air. After culture, cumulus cells were removed by hyaluronidase treatment and vortexing and oocytes were fixed and stained. No significant differences were observed between vitrified oocytes, oocytes recovered from vitrified ovarian tissues and non-vitrified control oocytes in the percentage of oocytes with acceptable staining per total number of oocytes fixed or with visible chromatin per total number of oocytes with acceptable staining. However, fewer (P<0.05) oocytes obtained from vitrified ovarian tissues (70%) reached metaphase II compared to vitrified oocytes (88%) and non-vitrified control oocytes (90%). In contrast, when oocytes with at least 3-5 layers of cumulus cells were considered from each of the three groups, no differences (P>0.05) were observed due to treatment in the percentages of oocytes developing to metaphase II. These results demonstrate that sheep oocytes can be successfully cryopreserved by vitrification of ovarian tissues and exhibit in vitro maturation rates similar to that of vitrified and non-vitrified oocytes.
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PMID:Survival of oocytes recovered from vitrified sheep ovarian tissues. 1198 74

Hyaluronic acid (HA) was derivatized with methacrylic esters used for the preparation of hydrogels via photopolymerization. Poly(ethylene glycol) diacrylate (PEG-DA) with a molecular weight of 570 was also used as a comacromonomer to improve elastic modulus and swelling behavior. The hydrogels were readily degraded by hyaluronidase and their mechanical properties could be modulated by HA molecular weight and concentration of PEG-DA. The incorporation of RGD peptides allowed modulation of the HA properties from cell non-adhesive to adhesive. Human dermal fibroblasts were cultured on the RGD, RDG, and non-functionalized HA hydrogels for up to 7d, showing adhesion and proliferation only with incorporated RGD.
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PMID:Photopolymerized hyaluronic acid-based hydrogels and interpenetrating networks. 1250 9

The physiological activity of hyaluronic acid (HA) polymers and oligomers makes it a promising material for a variety of applications. The development of HA-hydrogel scaffolds with improved mechanical stability against degradation and biochemical functionality may enhance their application to tissue engineering. In this report, a crosslinking strategy targeting the alcohol groups via a poly(ethylene glycol) diepoxide crosslinker was investigated for the generation of degradable HA hydrogels. To provide support for cell adhesion in vitro, collagen was incorporated into the HA solution prior to the crosslinking process. The hydrogels have a continuous exterior and a porous interior, with pore diameters ranging from 6 to 9 microm. HA and HA-collagen hydrogels degrade in the presence of hyaluronidase and collagenase enzymes, indicating that the chemical modification does not prevent biodegradation. Complete degradation of the hydrogels occurred within 14 days in hyaluronidase (100 U/ml) and 3 days in collagenase (66 U/ml). Pattern transfer was employed to introduce a surface topography onto the hydrogel, which was able to orient cell growth. Furthermore, the hydrogels could be functionalized with the biomolecule neutravidin by incorporation of biotin along the HA backbone. This biotinylation approach may allow attachment of bioactive molecules that are conjugated to avidin.
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PMID:Crosslinked hyaluronic acid hydrogels: a strategy to functionalize and pattern. 1527 10

Efficient and controlled gene delivery from biodegradable materials can be employed to stimulate cellular processes that lead to tissue regeneration. In this report, a substrate-mediated approach was developed to deliver DNA from hyaluronic acid-collagen hydrogels. The hydrogels were formed by crosslinking HA with poly(ethylene glycol) diglycidyl ether. Poly(ethylene imine)(PEI)/DNA complexes were immobilized to the substrate using either biotin/neutravidin or non-specific adsorption. Complexes were formed in the presence or absence of salt to regulate complex size, and resulted in complexes with z-average diameters of 1221.7 +/- 152.3 and 139.4 +/- 1.3 nm, respectively. During 48-h incubation in PBS or hyaluronidase, DNA was released slowly from the hydrogel substrate (<30% of immobilized DNA), which was enhanced by incubation with conditioned media (approximately 50% of immobilized DNA). Transgene expression mediated by immobilized, large diameter complexes was 3 to 7-fold greater than for small diameter complexes. However, the percentage of cells expressing the transgene was greater for small diameter complexes (48.7%) than for large diameter complexes (22.3%). Spatially controlled gene transfer was achieved by topographically patterning the hydrogel to pattern cell adhesion. Biomaterial-based gene delivery can be applicable to numerous tissue engineering applications, or as a tool to examine tissue formation.
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PMID:DNA delivery from hyaluronic acid-collagen hydrogels via a substrate-mediated approach. 1552 59

Acrylated hyaluronic acid (HA) was used as a scaffold for bone morphogenic protein-2 (BMP-2) and human mesenchymal stem cells (hMSCs) for rat calvarial defect regeneration. HA was acrylated by two-step reactions: (1) introduction of an amine group using adipic acid dihydrazide (ADH); (2) acrylation by N-acryloxysuccinimide. Tetrathiolated poly(ethylene) glycol (PEG-SH(4)) was used as a cross-linker by a Michael-type addition reaction and the hydrogel was formed within 10min under physiological conditions. This hydrogel is degraded completely by 100U/ml hyaluronidase in vitro. hMSCs and/or BMP-2 was added during gelation. Cellular viability in vitro was increased up to 55% in the hydrogels with BMP-2 compared with the control. For in vivo calvarial defect regeneration, five different samples (i.e., control, hydrogel, hydrogel with BMP-2, hydrogel with MSCs, and hydrogel with BMP-2 and MSCs) were implanted for 4 weeks. The histological results demonstrated that the hydrogels with BMP-2 and MSCs had the highest expression of osteocalcin and mature bone formation with vascular markers, such as CD31 and vascular endothelial growth factors, compared with the other samples. This study demonstrated that HA base hydrogel can be used for cell and growth factor carriers for tissue regeneration.
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PMID:Bone regeneration using hyaluronic acid-based hydrogel with bone morphogenic protein-2 and human mesenchymal stem cells. 1720 95

Hydrogels have been widely used in tissue engineering as a support for tissue formation or to deliver non-viral gene therapy vectors locally. Hydrogels that combine these functionalities can provide a fundamental tool to promote specific cellular processes leading to tissue formation. This report investigates controlled release of gene therapy vectors from hydrogels as a function of the physical properties for both the hydrogel and the vector. Hydrogels were formed by photocrosslinking acryl-modified hyaluronic acid (HA) with a 4-arm poly(ethylene glycol) (PEG) acryl. The polymer content, and relative composition of HA and PEG modulated the swelling ratio, water content, and degradation, which can influence transport of the vector through the hydrogel. All hydrogels had a water content of 94% or higher, though the water content and swelling ratio increased with a decrease in the PEG:HA ratio. Plasmids were stably incorporated into the hydrogel, with a majority of the release occurring during the initial 2 days. For incubation in buffer, the cumulative release increased with a decreasing PEG or increasing HA content, with approximately 20% to 80% released during the first week depending on the hydrogel composition. Hydrogels incubated in hyaluronidase, an enzyme that degrades HA, significantly increased plasmid release for hydrogels containing 4% PEG and 4% HA-Acryl. The encapsulation of plasmid complexed with polyethylenimine had less than 14% of the complexes released from the hydrogel both in the presence and absence of hyaluronidase. The limited release of the complexes likely results from the complex size and interactions between the vector and hydrogel. These studies demonstrate the dependence of non-viral vector release on the physical properties of the hydrogel and the vector, suggesting vector and hydrogel designs for maximizing localized delivery of non-viral vectors.
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PMID:Non-viral vector delivery from PEG-hyaluronic acid hydrogels. 1758 40


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