| First Author | Chatterjee A | Year | 2014 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 55 |
| Issue | 5 | Pages | 3127-39 |
| PubMed ID | 24713487 | Mgi Jnum | J:229880 |
| Mgi Id | MGI:5754711 | Doi | 10.1167/iovs.13-12755 |
| Citation | Chatterjee A, et al. (2014) AMP-activated protein kinase regulates intraocular pressure, extracellular matrix, and cytoskeleton in trabecular meshwork. Invest Ophthalmol Vis Sci 55(5):3127-39 |
| abstractText | PURPOSE: In this study, we investigate how adenosine monophosphate-activated protein kinase (AMPK) affects extracellular matrix (ECM) and cellular tone in the trabecular meshwork (TM), and examine how deletion of its catalytic alpha2 subunit affects IOP and aqueous humor clearance in mice. METHODS: Human TM tissue was examined for expression of AMPKalpha1 and AMPKalpha2, genomically distinct isoforms of the AMPK catalytic subunit. Primary cultured human TM cells were treated for 24 hours with the AMPK activator 5-amino-1-beta-Dffff-ribofuranosyl-imidazole-4-carboxamide (AICAR), under basal or TGF-beta2 stimulatory conditions. Conditioned media (CM) was probed for secreted protein acidic and rich in cysteine (SPARC), thrombospondin-1 (TSP-1), and ECM proteins, and cells were stained for F-actin. Cells underwent adenoviral infection with a dominant negative AMPKalpha subunit (ad.DN.AMPKalpha) and were similarly analyzed. Intraocular pressure, central corneal thickness (CCT), and aqueous clearance were measured in AMPKalpha2-null and wild-type (WT) mice. RESULTS: Both AMPKalpha1 and AMPKalpha2 are expressed in TM. AICAR activated AMPKalpha and suppressed the expression of various ECM proteins under basal and TGF-beta2 stimulatory conditions. AICAR decreased F-actin staining and increased the phospho-total RhoA ratio (Ser188). Transforming growth factor-beta2 transiently dephosphorylated AMPKalpha. Infection with ad.DN.AMPKalpha upregulated various ECM proteins, decreased the phospho-total RhoA ratio, and increased F-actin staining. AMPKalpha2-null mice exhibited 6% higher IOP and decreased aqueous clearance compared with WT mice, without significant differences in CCT or angle morphology. CONCLUSIONS: Collectively, our data identify AMPK as a critical regulator of ECM homeostasis and cytoskeletal arrangement in the TM. Mice that are AMPKalpha2-null exhibit higher IOPs and decreased aqueous clearance than their WT counterparts. |
