title: Excessive matrix metalloproteinase activity in diabetes: inhibition by tetracycline analogues with zinc reactivity.
abstract: Diabetes mellitus in rats is characterized by excessive activity of several matrix metalloproteinases (MMPs), notably collagenase(s) and gelatinase(s), in skin, gingiva, and other tissues. A number of tetracyclines (TCs), both antimicrobial compounds as well as chemically modified non-antimicrobial TC analogues (CMTs) are known to possess potent inhibitory activity against these enzymes. Three conventional antimicrobial TCs and six CMTs were used in this study. In vitro, doxycycline was shown to possess higher inhibitory capacity (i.e. lower IC(max)) against diabetic rat skin collagenase than either minocycline or tetracycline HCl. Addition of excess zinc partially reversed the proteinase inhibition by TCs. In vivo, using rats made diabetic with streptozotocin (STZ), oral administration of various TCs led to decreased weight loss and substantial reductions in the activity of both skin collagenase and skin gelatinase (primarily MMP-9, 92 kDa) without affecting blood glucose. Using an in vitro spectrophotometric technique, the Zn(++) reactivity of several CMTs was assessed and found to be positively related to the potency of these compounds as MMP inhibitors. One particular CMT (CMT-5, pyrazole analogue), which is neither antimicrobial nor capable of binding metal cations, did not inhibit the MMPs. TCs have potential utility in management of diabetic complications mediated by excessive activity of MMPs.
authors.affiliation: Department of Oral Biology and Pathology, School of Dental Medicine, State University of New York, Stony Brook, NY 11794-8702, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Ryan
authors.forename: A
authors.initials: A
authors.lastname: Usman
authors.forename: N S
authors.initials: NS
authors.lastname: Ramamurthy
authors.forename: L M
authors.initials: LM
authors.lastname: Golub
authors.forename: R A
authors.initials: RA
authors.lastname: Greenwald
mesh_terms: D000818:Animals; D003094:Collagen / Q000378:metabolism; D017364:Collagenases / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology*; D018093:Gelatinases / Q000378:metabolism; D005881:Gingiva / Q000201:enzymology; D008297:Male; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D015394:Molecular Structure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000201:enzymology; D013329:Structure-Activity Relationship; D013752:Tetracycline / Q000494:pharmacology; D013754:Tetracyclines / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D061965:Matrix Metalloproteinase Inhibitors; D013754:Tetracyclines; C117155:tetracycline CMT-3; C117154:tetracycline CMT-7; C117153:tetracycline CMT-8; C053450:4-des-dimethylaminotetracycline; D003094:Collagen; D017364:Collagenases; D018093:Gelatinases; D020782:Matrix Metalloproteinases; D013752:Tetracycline