Glaucoma is characterized by irreversible loss of axons from the optic nerve. The site of damage to the axons is at the level of the lamina cribrosa in the optic nerve head. It has been hypothesized that structural and biochemical abnormalities in the extracellular matrix (ECM) of the lamina cribrosa underlie the progressive compressive and remodelling of this connective tissue in glaucoma. The importance of proteases as mediators of ECM degradation in the pathogenesis of various diseases is indisputable. ADAMTS-like proteins are secreted proteins resembling members of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motif) family. In this work, we evaluated the ADAMTSL family (ADAMTSL1, ADAMTSL2, ADAMTSL3, ADAMTSL4 and ADAMTSL5) gene expression by Real Time PCR in human optic nerve tissue

We used 9 human eye optic nerve tissue, in 3 class of ages, <3, 20-40 and >60. Total RNA from the tissues was isolated using the Trizol according to the manufacturer’s instruction. RNA quality was assessed using density ratio of 28S to 18S rRNA bands. First strand cDNA synthesis from 1000 ng of total RNA was performed using avian myeloblastosis virus reverse transcriptase primed by random hexamers. Real time PCR was performed on a Corbett 65H0 machine using the QuantiFast SYBR Green PCR Kit. DNA was first denatured for 10 min at 94°C, and then amplified using cycles of 15 sec at 95°C, 30 sec at 60°C, and 30 sec at 72°C. The specificity of PCR products was confirmed by both melting curve analysis and gel agarose electrophoresis. GAPDH was used as the control gene in the real time PCR experiments. Analysis was performed by comparing normalized cycle threshold (CT) values of different samples.

. Our results show that the ADAMTSL genes are expressed in the optic nerve and ADAMTSL-5 has the highest levels expression. Also, expression of some genes increases with age in the optic nerve.

Our finding indicates that these genes may have potential roles in glaucoma pathogenesis.