Recent Findings on the Role of Gelatinases (Matrix Metalloproteinase-2 and -9) in Osteoarthritis

Table 1

Metalloproteinase-2 and metalloproteinase-9 chromosome location, biological effects and substrates of action.

Gene	Biological effects	Main substrates
MMP-2; 16q13-q21	(1) Adipocyte migration; (2) Apoptosis (amnion epithelial cells); (3) Conversion of vasodilator to vasoconstrictor; (4) ECM degradation; (5) Enhanced collagen affinity; (6) Epithelial cell migration; (7) Generation of vasoconstrictor; (8) Increased bioavailability of IGF1 and cell proliferation; (9) Increased bioavailability of TGF-β; (10) Mesenchymal cell differentiation with inflammatory phenotype; (11) Neural apoptosis leading to neurodegeneration; (12) Neurite outgrowth	(13) Aggrecan
		(14) Collagen type I
		(15) Collagen type III
		(16) Collagen type IV
		(17) Collagen type VII
		(18) Collagen type X
		(19) Collagen type XI
		(20) Decorin
		(21) Elastin
		(22) Fibrinogen
		(23) Gelatin
		(24) Laminin
		(25) Plasminogen
		(26) proMMP-9
		(27) proMMP-13
		(28) Vitronectin
MMP-9; 20q11.2-q13.1	(29) Bioavailability of TGF-β; (30) Generation of angiostatin-like fragment; (31) ECM degradation; (32) Enhanced collagen affinity; (33) Hypertrophic chondrocytes apoptosis and recruitment of osteoclast; (34) Pro-inflammatory; (35) Reduced IL-2 response; (36) Tumor cell resistance; (37) Thymic neovascularization	(38) Collagen type I
		(39) Collagen type IV
		(40) Collagen type VII
		(41) Collagen type X
		(42) Collagen type XI
		(43) Collagen type XVIII
		(44) Elastin
		(45) Fibronectin
		(46) Gelatin
		(47) Laminin
		(48) proMMP-2
		(49) proMMP-9
		(50) Vitronectin