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)

Hyaluronic acid (salt) (HA) has been chemically modified as a biomaterial for medical applications such as controlled drug release matrices, nerve guides and wound dressings. A series of HA derivatives, which include different ester types and different degrees of esterification, have been used to investigate the stability of these materials in testicular hyaluronidase. Gel permeation chromatography and capillary viscometer have been employed to determine the size of the molecules, the former used for the water insoluble derivatives that dissolve in dimethyl sulphoxide, the latter for the water soluble samples. The preliminary experimental results indicated that the molecular weight of fully esterified hyaluronic acid (both ethyl and benzyl esters) did not decrease after treatment in the enzyme for 7 and 14 days while the water soluble partially esterified HA were degraded by the enzyme producing a sharp reduction of viscosity within minutes. These observations tend to suggest that the carboxylic groups in the beta-glucoronic acid unit are the activation centre of this enzyme and the total blockage of these groups can restrict the cleavage of beta (1-->4) glycoside bonds by this enzyme.
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PMID:Biodegradation of hyaluronic acid derivatives by hyaluronidase. 806 Nov 27

The objectives of this study were to determine the viscoelastic shear properties of articular cartilage and to investigate the effects of the alteration of proteoglycan structure on these shear properties. Glycosidase treatments (chondroitinase ABC and Streptomyces hyaluronidase) were used to alter the proteoglycan structure and content of the tissue. The dynamic viscoelastic shear properties of control and treated tissues were measured and statistically compared. Specifically, cylindrical bovine cartilage specimens were subjected to oscillatory shear deformation of small amplitude (gamma degrees = 0.001 radian) over a physiological range of frequencies (0.01-20 Hz) and at various compressive strains (5, 9, 12, and 16%). The dynamic complex shear modulus was calculated from the measurements. The experimental results show that the solid matrix of normal articular cartilage exhibits intrinsic viscoelastic properties in shear over the range of frequencies tested. These viscoelastic shear properties were found to be dependent on compressive strains. Our data also provide significant insights into the structure-function relationships for articular cartilage. Significant correlations were found between the material properties (the magnitude of dynamic shear modulus, the phase shift angle, and the equilibrium compressive modulus), and the biochemical compositions of the cartilage (collagen, proteoglycan, and water contents). The shear modulus was greatly reduced when the proteoglycans were degraded by either chondroitinase ABC or Streptomyces hyaluronidase. The results suggest that the ability of collagen to resist tension elastically provides the stiffness of the cartilage matrix in shear and its elastic energy storage capability. Proteoglycans enmeshed in the collagen matrix inflate the collagen network and induce a tensile prestress in the collagen fibrils. This interaction of the collagen and proteoglycan within the cartilage matrix provides the complex mechanism that allows the tissue to resist shear deformation.
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PMID:Viscoelastic shear properties of articular cartilage and the effects of glycosidase treatments. 828 21

A series of oligosaccharides was prepared from hyaluronate by depolymerisation with bovine testicular hyaluronidase. Complete assignment of the 1H and 13C NMR spectra was obtained for the disaccharide, the tetrasaccharide, and the NaBH4-treated tetrasaccharide, by using various 1D and 2D NMR methods. The 1H assignments for the tetrasaccharide differ from the incomplete data reported recently (ref. 11). The 13C NMR spectra of the aqueous di-, tetra-, hexa-, and octa-saccharides of this series show that all resonances, apart from those subject to obvious end effects, have chemical shifts comparable to those of the corresponding resonances of hyaluronate in D2O. The observed 13C chemical shifts suggests that cooperative intramolecular hydrogen bonds probably play a minor role in determining the conformation of hyaluronate in water.
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PMID:NMR studies of oligosaccharides derived from hyaluronate: complete assignment of 1H and 13C NMR spectra of aqueous di- and tetra-saccharides, and comparison of chemical shifts for oligosaccharides of increasing degree of polymerisation. 835 43

The aim of the present study was to evaluate the ability of Porphyromonas gingivalis to degrade hyaluronic acid. No hyaluronidase activity was detected using a turbidimetric method, whereas a standard plate assay showed a positive reaction for P. gingivalis. We postulated that the high proteolytic activity of P. gingivalis may account for this observation. A modified plate assay was designed to avoid false-positive reactions caused by proteolytic bacteria. The new assay, based on the formation of a water-insoluble salt between hyaluronic acid and the polyanion cetylpyridinium chloride, indicated that P. gingivalis does not have hyaluronidase activity. By this modified plate method, it was found that among 24 different oral bacterial species tested, Propionibacterium acnes and Prevotella oris were the only species that possess hyaluronidase activity.
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PMID:Evidence for the absence of hyaluronidase activity in Porphyromonas gingivalis. 839 79

Immunological methods were used to determine the identity of the major components comprising a network of electron-dense seams (described by the authors in a previous work) within the extracellular matrix of medial collateral ligament (MCL) from humans and rabbits. Tissue obtained from MCL midsubstance was subjected to pre-embedding labelling with colloidal gold at the electron microscopic level with monoclonal antibodies (MAbs) against type-VI collagen and chondroitin sulphate (CS), before and after digestion with chondroitinase ABC and testicular hyaluronidase. Tissue labelled with anti-type-VI MAbs showed gold conjugates attached to the microfilamentous component of the seams both before and after enzyme digestion, which confirmed the identity of the beaded microfilaments as type-VI collagen. Treatment of the tissue with anti-CS MAbs resulted in labelling of undigested tissue only. In these treatments, gold particles were found attached to granules that were interspersed throughout the network of type-VI microfilaments. Both the granules and gold labels were absent from the network following enzyme digestion. Thin nonbeaded microfilaments that did not label with anti-type-VI MAbs also were present within the seams. The loss of these nonbeaded microfilaments following enzyme digestion suggested that they might represent strands of hyaluronan. The codistribution and sequestering of type-VI collagen and CS within discrete seams or channels suggests that these regions of the MCL midsubstance may contain higher concentrations of water than the surrounding dense fibrillar matrix.
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PMID:Ultrastructural immunolocalization of type-VI collagen and chondroitin sulphate in ligament. 841 Apr 68

Our methodology for obtaining zona-free ova from golden hamster females (Mesocricetus Auratus Waterhouse) is described here. Five groups of 5 females were superovulated injecting intraperitoneally pregnant mare gonadothropins (PMG) at different dosages. The control group received 0.25 ml of distilled water. We harvested 653 ova from the stimulated females with an average of 32.65 per individual (range 16-52). The control group produced a total of 50 ova with an average of 10 (range 0-14). PMG optimum dose was 25 IU with an average of 39 (S.D. +/- 10.93) (n = 195 ova). The best conditions for denuding the cumulus was a 0.01% hyaluronidase solution with an average time of 10 minutes (S.D. +/- 03'56"). The optimum conditions for digesting the zona was 0.20% trypsin during 03'20" (S.D. +/- 01'19"). The proof that the ova were not damaged by the procedure was by means of a supravital stain (Eosin Y). All mature ova (N = 681) were not affected by enzymes or manipulation. Final preparation used a 1% acetic acid fixation and staining with 0.01% methylene blue, both acting for 1-3 minutes. Animal gametes give us the opportunity to substitute human ova in biology of reproduction studies and experiments, avoiding technical, ethical and moral problems.
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PMID:[Obtaining zona-free ova from the golden hamster (Mesocricetus auratus Waterhouse)]. 848 15

Orbital regional anesthesia is the only circumstance where hyaluronidase is routinely added to local anesthetics to accelerate the onset of the block. The aim of this study was to compare the pharmacokinetics of lidocaine and bupivacaine with or without hyaluronidase for peribulbar blockade. Twenty-one patients scheduled for cataract surgery with lens implantation were included in this prospective randomized study. Peribulbar blocks were achieved with plain bupivacaine 0.5% (5.5 mL), lidocaine 2% (5.5 mL), and hyaluronidase (100 IU = 2 mL) (n = 10) ir sterile water (2 mL) (n = 11). Plasma bupivacaine and lidocaine concentrations were measured by high-performance liquid chromatography at regular intervals from the end of the local anesthetic injection until the 360th minute. Maximum plasma concentration (Cmax) and time to reach Cmax (Tmax) were obtained for all the patients except one who needed a supplementary injection and was excluded from the study. The time to onset and duration of the analgesia and akinesia were monitored at the times of sampling. Motor blockade was incomplete in two patients in each group without affecting surgery. The Tmax and absorption half-life (t1/2a) of lidocaine and bupivacaine were not different within each group (P > 0.05). The Tmax of lidocaine was shorter in the presence of hyaluronidase (17.1 +/- 2.6 min vs 32.7 +/- 6.0 min) as well as the Tmax of bupivacaine (16.8 +/- 3.0 min vs 26.5 +/- 4.4 min). The Cmax of lidocaine and bupivacaine were not modified by the addition of hyaluronidase. The clearance, terminal half-life, and volume of distribution were not different between groups. The absorption of lidocaine and bupivacaine from the peribulbar space are hastened by the addition of hyaluronidase. The Tmax of lidocaine is not different from that of bupivacaine within each group suggesting that the absorption of local anesthetics is minimally influenced by the liposolubility of the drugs. Moreover, hyaluronidase influences the absorption kinetics of both lidocaine and bupivacaine in the same manner.
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PMID:The role of hyaluronidase on lidocaine and bupivacaine pharmacokinetics after peribulbar blockade. 861 Aug 68

The pulmonary interstitium may affect the movement of water, macromolecules, and inflammatory cells between capillaries and lymphatics. Hyaluronan (hyaluronic acid), a glycosaminoglycan of the interstitial matrix, helps to retain water in the lung interstitium and to exclude proteins. Marked reduction of interstitial hyaluronan by infusion of hyaluronidase decreased the resistance to fluid transport and decreased water retention in the interstitium, and thus accelerated lymphatic removal of fluid filtered across capillary walls. However, reduction of hyaluronan increased the accumulation of neutrophils in the lung and exacerbated acute lung injury caused by pancreatic elastase. Interstitial hyaluronan may protect against acute inflammatory changes in elastase-induced lung injury.
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PMID:[The role of interstitial hyaluronan in acute lung injury]. 875 11

Histochemical staining of the epiphysial growth plate revealed that free hyaluronan (i.e. available to the staining probe) was restricted to the zone of hypertrophy, where it was located in the pericellular space between the chondrocytes and the edge of the lacunae. Furthermore, the amount of hyaluronan staining was directly proportional to the size of the lacunae. Autoradiographic analysis of growth plates cultured with isotopically labeled glucosamine indicated that at least a portion of this hyaluronan was newly synthesized by the hypertrophic chondrocytes. Since hyaluronan can adsorb large amounts of water, it is possible that it exerted a hydrostatic pressure on the surrounding territorial matrix and thereby caused the expansion of hypertrophic lacunae. To assess this possibility, segments of the growth plate were placed in organ culture under different conditions. Under normal culture conditions, a band of hyaluronan staining migrated across the segments coinciding with the enlargement of lacunae in these regions, and the segments, as a whole, increased in size. In contrast, when the segments were cultured in the presence of hyaluronidase, which degraded the pericellular hyaluronan, the lacunae did not undergo enlargement and the overall size of the segments did not increase. These results suggest that the production of hyaluronan contributes to the enlargement of hypertrophic lacunae which is important for determining both the body's stature and proportions.
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PMID:Hyaluronan contributes to the enlargement of hypertrophic lacunae in the growth plate. 883 56

An accumulation of the connective tissue component, hyaluronan (HA), is known to occur in both syngeneic and allogeneic kidney grafts during the early postoperative period. The presence of HA in the interstitial tissue of the grafts is paralleled by an increased water content, suggesting a role for HA in the development of the transplantation edema. In the present work, the kidney content and distribution of HA was studied in a model of warm renal ischemia in the rat to investigate whether renal ischemia is associated with HA accumulation. Seventy-two hours after a period of warm renal ischemia (30 or 60 min) significantly higher amounts of HA were observed in the left kidney that had been exposed to ischemia, than in the right, healthy kidney. The most pronounced increase was found to occur in the cortex (20 to 40 times), a structure where there normally is almost no presence of HA. In addition, there was a correlation between the relative water content of the kidney and the amount of HA possible to extract from the tissue. The renal accumulation of HA and water was prevented by daily intravenous administration of hyaluronidase. We conclude that renal ischemia induces an accumulation of HA that may increase the risk for the development of interstitial edema, a situation that may be circumvented by hyaluronidase treatment.
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PMID:Experimentally-induced warm renal ischemia induces cortical accumulation of hyaluronan in the kidney. 888 81


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