No abstract

No abstract

The amounts and activities of matrix metalloproteinases (MMPs) were studied in human myometrium and uterine leiomyomas in various stages of growth. It was found that both myometrium and the investigated tumors contain collagenolytic enzymes. MMP-1, MMP-2, MMP-3 and MMP-9 were found. Gelatinase A (MMP-2) is the most abundant. In control myometrium only 10% of this enzyme exists in an active form, whereas in tumors, especially in large ones, the values reach 30%. It is suggested that the high activity of MMP-2 is responsible for remodelling of extracellular matrix in the growing tumors.

In this paper the authors present studies on the effect of auxin precursors and chemical analogues on the growth and biochemical composition in Chlorella pyrenoidosa (Chlorophyceae). Among auxin precursors tryptamine exhibited slightly higher stimulative activity in regard to fresh and dry weight, mineral substances, chlorophylls, carotenoids, monosaccharides (aldohexoses) and water-soluble proteins content in Ch. pyrenoidosa cells as compared to anthranilic acid. Among auxin analogues used phenoxyacetic acid and naphthyl-3-acetic acid had the strongest stimulative effect of the above-mentioned parameters. Their activity was significantly higher than that of auxin precursors. The activity of naphthyl-3-sulphonic acid was slightly lower than that of tryptamine, whereas the stimulation by 2,4-dichlorophenoxyacetic acid was similar to that of anthranilic acid. In Ch. pyrenoidosa cells 2,4-dichlorophenoxyacetic acid and naphthyl-3-sulphonic reached their maximum activity at the latest (between the 15th or 16th day) of the culturing, whereas tryptamine, phenylacetic acid, naphthyl-3-acetic acid and indolyl-3-acetic acid - at the earliest (between the 8th or 12th) day

It was found that both normal human myometrium and uterine leiomyoma contain several glycosaminoglycans. In contrast to many normal and tumour tissues the amount of hyaluronic acid is very low and the proportional amount of sulphated glycosaminoglycans is distinctly higher. It is of interest that heparan sulphate is the major glycosaminoglycan component both in normal myometrium, and in leiomyoma. The amount of hyaluronic acid in myometrium and in the leiomyoma is very low. No significant change in hyaluronate content was observed during the tumour growth. In contrast to that the amount of some sulphated glycosaminoglycans (heparan sulphate, keratan sulphate, chondroitin sulphates and heparin) distinctly increased. It is suggested that some of the GAGs participate in the creation of a storage depot for biologically active molecules (growth factors, enzymes) which are thereby stabilized and protected. Hydrolytic degradation of some GAGs may result in the release of some cytokines which may promote the tumour growth and stimulate collagen biosynthesis by tumour cells.

The abdominal aortic aneurysm (AAA) wall represents an extreme example of arterial remodeling with disturbed elastin, collagen and proteoglycan metabolism. The aim of this study was to evaluate enzymes involved in the degradation of glycosaminoglycan chains and core proteins of proteoglycans in the AAA wall. The study material consisted of wall samples from 10 AAA. Fragments of 5 normal abdominal aortas from organ donors were used as a control. The activity of endoglycosidases, exoglycosidases and sulfatases was measured using colorimetric methods. To assess matrix metalloproteinases (MMPs), Western blot and zymography were performed. The activity of endoglycosidase degrading chondroitin-4-sulfate was lower in the AAA wall. Endoglycosidase degrading heparan sulfate and dermatan sulfate, arylosulfatase B, as well as all the exoglycosidases assessed demonstrated higher activities in the AAA wall. Furthermore, increased expression of MMP1, MMP2 and MMP9 was also shown in the AAA wall. Zymography revealed decreased activity of pro-MMP2 and presence of pro-MMP9 in the AAA wall compared to the wall of normal aorta. Extensive changes in the activity of glycosaminoglycan-degrading enzymes and MMPs may influence the organization of the extracellular matrix network and lead to previously demonstrated changes in the proteoglycan and glycosaminoglycan content in the AAA wall.

The aim of the study was to examine the content and molecular differentiation of glycosaminoglycans (GAGs) in the wall of varicose veins. The studied material consisted of normal, varicose veins and varicose veins complicated by thrombophlebitis collected during operations on 26 patients. In the wall of varicose veins the mean GAGs’ content as well as the content of sulphated GAGs, except heparan sulphate was increased, whereas the amount of hyaluronic acid was decreased. Furthermore, the increased quantitative ratio between sulphated and nonsulphated GAGs was demonstrated. The results indicate an evident extracellular matrix remodelling in the wall of varicose veins particularly those complicated by thrombophlebitis, that is characterised by alterations in the content and molecular differentiation of GAGs.

The walls of human abdominal aortas and atherosclerosis-induced aneurysms contain similar amounts of collagen. The quantitative ratio between collagens of various types of this protein does not differ significantly either, whereas solubility of the collagen in aneurysmal wall and its susceptibility to the action of EDTA are distinctly decreased. In contrast with collagen, the amount of elastin in aneurysms is significantly lower. Total amount of glycosaminoglycans slightly decreased as compared with that of normal tissue, but the ratio of particular compounds varies. The percentage of chondroitin sulphate is increased and that of heparan sulphate significantly decreased. The significance of these changes in pathogenesis of aneurysms is discussed.