Effect of carrageenin and cortisone on the formation of cultivated connective tissue. I. Isolation and characterisation of glycosaminoglycans

Studies on the metabolism of glycosaminoglycans under the influence of new herbal anti-inflammatory agents

The in vivo effect of an herbal based, non-steroidal anti-inflammatory product, salai guggal, prepared from the gum resin exudate of Boswellia serrata and its active principle "boswellic acids" on glycosaminoglycan metabolism has been studied in male albino rats. The biosynthesis of sulfated glycosaminoglycans, as evaluated by the uptake of [35S]sulfate, and the content of glycosaminoglycans were measured in specimens of skin, liver, kidney and spleen. Statistical analysis of the data obtained with respect to the boswellic acids and salai guggal were compared with those of ketoprofen. A significant reduction in glycosaminoglycan biosynthesis was observed in rats treated with all of the drugs. Glycosaminoglycan content was found to be decreased in the ketoprofen-treated group, whereas that of the boswellic acids or salai guggal treated groups remained unaltered. The catabolism of glycosaminoglycans was followed by estimating the activities of lysosomal glycohydrolases, namely beta-glucuronidase, beta-N-acetylglucosaminidase, cathepsin B1, cathepsin B2 and cathepsin D, in tissues and by estimating the urinary excretion and hexosamine and uronic acid. The degradation of glycosaminoglycans was found to be reduced markedly in all drug-treated animals as compared to controls. The potential significance of boswellic acids and salai guggal was discussed in the light of changes in the metabolism of glycosaminoglycans.

Epidermal growth factor (EGF) prevents methylprednisolone-induced inhibition of wound healing

Subcutaneously implanted cylindrical hollow viscose cellulose sponges were used to study the effect of locally applied epidermal growth factor (EGF) on methylprednisolone-induced inhibition of granulation tissue formation in rats. In in vivo studies the sponges were treated immediately after implantation with a single injection of 2 mg (approximately 1.7 x 10(-3) M) of depot methylprednisolone or with its carrier solution only. Thereafter the implants were injected daily with 5 micrograms of EGF or with its carrier solution 0.1% albumin for 7 days. Methylprednisolone treatment decreased the accumulation of nucleic acids, collagen, and glycosaminoglycans in the developing granulation tissue. After daily injections of EGF the concentrations of these tissue components returned close to the control values. In cultures of rat granulation tissue fibroblasts, 10(-4) M and 10(-3)M methylprednisolone decreased collagen synthesis by 41 and 81% from the control level, respectively. In the presence of methylprednisolone EGF treatment could not increase collagen synthesis of fibroblasts. Methylprednisolone treatment resulted in a dose-dependent reduction in pro alpha 1(I) collagen mRNA levels, which was partially inhibited by low EGF concentrations (1 and 10 ng/ml). In the presence of methylprednisolone all concentrations of EGF increased fibronectin mRNA levels in a dose-dependent manner. It is concluded that EGF treatment can prevent the inhibitory effect of methylprednisolone on wound healing by stimulating fibroblast proliferation but does not stimulate collagen synthesis per cell.

Isolation, partial characterization, and biological properties of polysaccharides from crude papain

Two polysaccharides have been isolated from crude papain by precipitation of papain with ammonium sulfate, further precipitation of other proteins with trichloroacetic acid, and chromatography of the supernatant on DEAE-cellulose. The first polysaccharide to be eluted, designated PP-I, contained D-glucuronic acid, D-glucose, D-galactose, L-arabinose, and L-rhamnose, in the approximate molar ratios of 4:1:12:10:4. The other (PP-II), eluted at a higher salt-concentration, contained the same sugars (with about one-third less glucose and more uronic acid) in the approximate molar ratios of 13:1:40:26:12. Reduction of the uronic acid groups of PP-II produced a polysaccharide (PP-II-R) containing the same sugars in the approximate molar ratios of 2:11:37:28:12. Hydrolysis of a mixture of the two polysaccharides yielded an aldobiouronic acid, D-glucosyluronic acid-D-galactose. Neither polysaccharide preparation contained protein. These polysaccharides dramatically affected aggregation and alignment of normal human fibroblasts but had no effect on a mouse embryo fibroblast aneuploid cell-line that does not exhibit contact inhibition of growth or movement. In aggregating cells, these polysaccharides caused the cells to behave as contact-inhibited cells, that is, cell division and nuclear area were decreased.

Glucocorticoid and starvation effect on glycosaminoglycans in vascular connective tissue. Biochemical studies on repair processes in rabbit aorta

Male rabbits were injured by a single mechanical dilatation injury of aorta and then injected with prednisone 2 mg/kg or saline for 14 days or subjected to starvation. The biosynthesis of the sulfated glycosaminoglycans as evaluated by the uptake of 35S-sulfate and the content of the glycosaminoglycans were measured on the intima-media layer of the descending thoracic aorta. The results indicate that prednisone may inhibit the biosynthesis of heparan and/or dermatan sulfate while starvation increases the biosynthesis of all the sulfated glycosaminoglycans. No alterations were observed in the total amount of glycosaminoglycans in aorta following glucocorticoid injection or starvation. The metabolism of aortic glycosaminoglycans during repair is less sensitive to the action of prednisone than in undamaged aorta. This contrasts with the effect of prednisone on the metabolism of aortic collagen.

The acid mucopolysaccharides (glycosaminoglycans) in secondary cultures of embryonic rat fibroblasts

In secondary cultures of embryonic rat fibroblasts the protein-free acid mucopolysaccharides were separated by cetylpyridinium chloride fractionation and identified afterwards. The following acid mucopolysaccharides were found: hyaluronic acid, chondroitin, 2 heparan sulphate fractions, chondroitin-4-sulphate, chondroitin-6-sulphate, and dermatan sulphate.