Hyaluronidase activity in gingival crevicular material and in peritoneal exudate leukocytes in dogs

Histochemical localization at the electron microscopic level of sulfated glycosaminoglycans in the rat gingiva

Using the high iron diamine thiocarbohydrazide silver proteinate (HID-TCH-SP) staining technique, we investigated ultrastructural localization of sulfated glycosaminoglycans (GAGs) in the rat gingiva shortly after eruption, especially those associated with internal and external basal laminae. In the apical portion of the internal basal lamina, HID-TCH-SP stain deposits were distributed mainly in the region of the lamina lucida located between the lamina densa and the distal surface membrane of the junctional epithelium and inside the depression of the distal surface membrane adjacent to the basal lamina. Stain deposits were also detected on the surface membrane of the cytoplasmic protrusion. Interestingly, the density of HID-TCH-SP stain deposits in the internal basal lamina was highest in the apical portion of the junctional epithelium and decreased in the coronal direction, finally tending to disappear completely. On the other hand, in the external basal lamina the deposits were localized in the whole region of the basal lamina or at both sites of the lamina densa. HID-TCH-SP stain deposits were also detected external to the lamina densa in the basement membrane associated with capillaries and in the connective tissue where they were distributed in close relation to collagen fibrils. Testicular hyaluronidase digested most HID-TCH-SP stain deposits in the connective tissue, whereas those in the region of basement membranes resisted this enzymatic digestion.

Hyaluronidase activity of rabbit skin wound granulation tissue fibroblasts

The objective of this work was to identify and compare hyaluronidase activities of normal dermal and dermal wound granulation tissue fibroblasts. Direct evidence of the fibroblast as a source of tissue hyaluronidase was obtained. Fourth passage rabbit dermal fibroblasts were harvested on culture days 4, 8, 14, 18, and 22. Hyaluronidase activity and [35S]-sulfate- or [3H]-glucosamine-labeled glycosaminoglycans (GAGs) were monitored. Hyaluronidase assays were performed on medium and cellular fractions at the designated intervals. Enzyme activity of cellular fractions for both normal dermal and 14-day post-wound granulation tissue fibroblasts increased progressively through culture day 8. Thereafter (days 14-22), an eight-fold drop in cellular activity was coupled with cell death and emergence of hyaluronidase activity in medium fractions. Marked increases in degradation of secreted matrix components were concurrent with lysis-induced release of hyaluronidase. In this culture system, hyaluronidase activity was confined exclusively to cellular fractions and was released into the medium only under non-physiological conditions conducive to cellular death and lysis. Accordingly, this work suggests that previously reported skin wound hyaluronidases may be of fibroblastic origin and that susceptible GAGs are not degraded extracellularly, but, rather, must be internalized as a prerequisite to depolymerization.

Hyaluronic acid and hyaluronidase activity in gingival exudate from sites of acute ulcerative gingivitis in man

Gingival exudates from sites of acute ulcerative gingivitis (AUG) and chronic gingivitis (CG) in adults were investigated by cellulose-acetate electrophoresis for the hyaluronic acid (HA) content and assayed for the levels of HA-degrading enzymes. HA was the only glycosaminoglycan (GAG) in gingival exudate from CG sites. HA was not detected at untreated AUG sites but was evident, at increasing levels, after two and seven days of effective antibacterial treatment. In AUG exudates, the total HA-degrading enzyme activity, of bacterial origin, decreased to approx. 30 and 10 per cent of the high initial levels after two and seven days of treatment respectively, to that level found at sites of CG. The specific activity of HA-degrading enzyme of lysosomal origin was low initially and increased with treatment to a level comparable to CG. The notable absence of HA from gingival exudate from sites of untreated AUG thus appears to result from the increased levels of bacterial hyaluronidase. Electrophoresis of gingival exudate may be an indirect method of monitoring the rate of response of AUG to different antibacterial treatments.

Identification and characterization of rabbit buccal mucosal hyaluronidase

This study establishes the existence of a mammalian buccal mucosal hyaluronidase having properties typical of a lysosomal enzyme. Mucosal hyaluronidase exhibited a distinct substrate preference for hyaluronic acid, generated saturated de-polymerization products by endoglycosidic hydrolysis, and possessed a pH optimum of 3.5 and an isoelectric point of 5.9.

Evaluation and modification of spectrophotometric procedures for analysis of lactate dehydrogenase, beta-glucuronidase and arylsulphatase in human gingival crevicular fluid collected with filter-paper strips

Filter-paper strips were used to collect GCF, and the sample eluted into a larger volume of diluent. This procedure allows for detection of site-to-site variation in GCF volume, and provides a 300-400 microliter sample for analysis of lactate dehydrogenase (LDH), beta-glucuronidase (BG) and arylsulphatase (AS) activities by a standard (serum) spectrophotometric assay modified for increased sensitivity. The results indicate that although the standard assay for LDH (based on oxidation of NADH) was adequate for detecting low activity in GCF samples, the modification doubled the sensitivity and allowed the use of less sample volume, thereby providing additional material for other assays. The standard assay for BG based on phenolphthalein being generated from phenophthalein glucuronic acid was not adequate for use in GCF analysis. The modification used increased assay sensitivity five-fold and allowed smaller samples to be used. The serum assay for AS (conversion of nitrocatechol sulphate to nitrocatechol) was accurate to the lower limit of AS activity in GCF and could be used without modification. The results emphasize the need to evaluate critically standard spectrophotometric assays for sensitivity when studying physiologically-collected GCF.

Degradation of basement membrane collagen by proteinases from human gingiva, leukocytes and bacterial plaque

Basement membranes in human gingiva are found in dento-epithelial junction, epithelial-connective tissue junction and endothelium-connective-tissue junction where they have important attachment and filtering functions. The ability of plaque and gingiva-derived proteinases to degrade Type IV collagen, the major protein of basement membranes, was examined in vitro. The basement membrane collagen (Type IV) isolated from bovine lens capsules was incubated in the presence of enzyme samples. The degradation was assayed by the release of hydroxyproline from the insoluble substrate and by examining the peptide pattern of the residue by polyacrylamide gel electrophoresis. Salt extracts of inflamed gingival specimens degraded basement membrane collagen into soluble form and produced degradation products that were similar to those produced by human leukocyte extracts. Gingival crevicular fluid collected from patients with severe adult periodontitis also digested the substrate but the degradation pattern was different from the leukocyte and gingival extract samples. The pattern closely resembled the degradation produced by bacterial plaque extracts. A third type of cleavage was observed when collagenase from Clostridium histolyticum was incubated with basement membrane collagen. Crevicular fluid and the extracts from gingiva, leukocytes and plaque also contained gelatinase and elastase-like enzyme activities that have earlier been shown to be potent in degrading basement membrane. It was concluded that enzymes capable of degrading basement membrane collagen in gingivitis and periodontal disease may originate from both plaque bacteria and human leukocytes. It also appeared that the enzymes responsible are more likely to be gelatinase and elastase-like enzymes than specific collagenases.

Penetration of dental plaque components into gingiva: sequential topical treatments with hyaluronidase and streptococcal polysaccharide in rats

EIGHTY-FIVE Sprague-Dawley rats were used in two experiments to determine the conditions necessary to permit transepithelial penetration by deleterious macromolecules in murine oral mucosa. In experiment one, Group I was a water and diet control; Group II mucosa was treated with hyaluronidase; Group III with streptococcal polysaccharide; and Group IV with hyaluronidase, followed by treatment with the polysaccharide. In the second experiment, the histological effects of the streptococcal polysaccharide were quantified by administering a series of concentrations, from 10 mg/ml to 100 microgram/ml. The results suggest that tissue-damaging plaque components, such as hyaluronidase and polysaccharide, act in combination to pass through the epithelial structures into the subjacent connective tissues to cause destructive changes in rat gingiva. Such changes may possibly be related to those seen in the periodontium when it is adjacent to dental plaque.

Basement membrane changes under neoplastic oral mucous membrane. Ultrastructural observations, review of the literature, and a unifying concept

This study explores the morphologic nature of the basement membrane under neoplastic oral mucous membrane. Of particular interest is the progression of changes associated with dysplasia, carcinoma in situ, and invasive carcinoma. On the basis of a critical review of the literature and our own ultrastructural observations, we present a unifying concept for the development of these basement membrane changes. This concept proposes that neoplastic epithelial cells may produce a collagenolytic enzyme which is released into the epithelial intercellular spaces. This enzyme permeates to the basement membrane, causes breaks in the basement membrane, and focal loss of stromal area contiguous with intercellular spaces. The neoplastic basal cells develop pseudopodia that eventually extend through the breaks in the basement membrane. This concept suggests that the basement membrane changes herald the progression of carcinoma in situ to invasive carcinoma.

Enzymatic penetration through intact sulcular epithelium

To explore possible enzymatic penetration through intact sulcular epithelium tritium labeled hyaluronidase and collagenase were applied to the gingival sulcus of five white lip marmosets. One quadrant per monkey remained untreated. Each remaining quadrant was randomly assigned to one of the following modalities of application: (a) tritiated hyaluronidase, (b) tritiated collagenase, (c) unlabeled hyaluronidase followed by tritiated collagenase, (d) inactivated tritiated hyaluronidase, or (e) normal saline as experimental controls. The enzymes were applied by means of a Pasteur disposable pipette. Eight drops were administered over a 4-minute period, one every 30 seconds. After a 5-minute waiting period a second series of eight applications was given over a 4-minute period. Radioautographic and standard histologic materials were obtained. Results suggest that: 1. Hyaluronidase has the ability to penetrate through intact nonkeratinized sulcular epithelium, widening the intercellular epithelial spaces and disorganizing the connective tissue ground substance. 2. Collagenase per se does not have the ability to penetrate through the intact sulcular epithelium. Its effect remains confined only to the superficial layers of the epithelium. 3. However, when collagenase application is preceded by hyaluronidase, collagenase spreads easily through the epithelium and deeply into the connective tissue. Hyaluronidase acts unquestionably as a spreading factors.