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Modulation of neutral matrix metalloproteinases of involuting rat mammary gland by different cations and glycosaminoglycans
Author(s) -
Ambili M.,
Sudhakaran P.R.
Publication year - 1999
Publication title -
journal of cellular biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.028
H-Index - 165
eISSN - 1097-4644
pISSN - 0730-2312
DOI - 10.1002/(sici)1097-4644(19990501)73:2<218::aid-jcb8>3.0.co;2-c
Subject(s) - gelatinase , matrix metalloproteinase , chemistry , chondroitin sulfate , basement membrane , gelatinase a , collagenase , glycosaminoglycan , enzyme , sulfatase , biochemistry , biology , microbiology and biotechnology
The synthesis and regulation of the matrix metalloproteinases (MMPs) are important factors contributing to the involution of mammary gland. In order to understand the role of these MMPs in involution and in remodeling of the mammary gland, the different MMPs (130K, 68K, and 60K gelatinases) were partially purified by gel filtration and affinity chromatography over gelatin Sepharose and subjected to kinetic analysis. Comparative analysis of the different gelatinases showed that the 130K that appears at the early involutary phase and the constitutive 68K enzyme are more specific for Col IV of the basement membrane, while the inducible 60K that appeared at the later phase of involution degraded Col I more efficiently. These neutral proteinases required Ca 2+ /Zn 2+ for their activity and the analysis of cation dependence revealed that Ca 2+ at 10 mM concentration and above completely inhibited the enzyme. The 60K was active at very low concentration of Zn 2+ (5 μM); but at higher concentration of Zn 2+ (2 mM), where the 68K and 130K were active, the 60K gelatinase was inhibited, indicating a difference in the cation dependence of these enzymes. Chondroitin sulfate A and chondroitin sulfate C caused inhibition of the 130K, 68K, and 60K, while hyaluronic acid and heparin did not show any effect, suggesting that the chondroitin sulfate proteoglycan that decorates collagen in the ECM can modulate the activity of the collagenases in vivo. These results suggest that the 130K gelatinase expressed during the early phase of involution degraded Col IV of the basement membrane, making the 60K gelatinase formed at a later stage of involution more accessible to its preferred substrate (Col I of the underlying stroma), highlighting the role of these MMPs in mammary gland involution. J. Cell. Biochem. 73:218–226, 1999. © 1999 Wiley‐Liss, Inc.