title: The formation of cortical actin arrays in human trabecular meshwork cells in response to cytoskeletal disruption.
abstract: The cytoskeleton of human trabecular meshwork (HTM) cells is known to be altered in glaucoma and has been hypothesized to reduce outflow facility through contracting the HTM tissue. Latrunculin B (Lat-B) and Rho-associated protein kinase (ROCK) inhibitors disrupt the actin cytoskeleton and are in clinical trials as glaucoma therapeutics. We have previously reported a transient increase in HTM cell stiffness peaking at 90 min after Lat-B treatment with a return to pretreatment values after 270 min. We hypothesize that changes in actin morphology correlate with alterations in cell stiffness induced by Lat-B but this is not a general consequence of other cytoskeletal disrupting agents such as Rho kinase inhibitors. We treated HTM cells with 2 µM Lat-B or 100 µM Y-27632 and allowed the cells to recover for 30-270 min. While examining actin morphology in Lat-B treated cells, we observed striking cortical actin arrays (CAAs). The percentage of CAA positive cells (CPCs) was time dependent and exceeded 30% at 90 min and decreased after 270 min. Y-27632 treated cells exhibited few CAAs and no changes in cell stiffness. Together, these data suggest that the increase in cell stiffness after Lat-B treatment is correlated with CAAs.
authors.affiliation: Department of Biomedical Engineering / University of California, Davis.
authors.forename: Kaitlin C
authors.initials: KC
authors.lastname: Murphy
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Morgan
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Wood
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.
authors.forename: Adeline
authors.initials: A
authors.lastname: Sadeli
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.|Department of Ophthalmology & Vision Science, School of Medicine / University of California, Davis.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Murphy
authors.affiliation: Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.
authors.forename: Paul
authors.initials: P
authors.lastname: Russell
mesh_terms: D000199:Actins / Q000378:metabolism*; D000577:Amides / Q000494:pharmacology; D000959:Antihypertensive Agents / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology*; D002468:Cell Physiological Phenomena; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D011725:Pyridines / Q000494:pharmacology; D053778:Thiazolidines / Q000494:pharmacology*; D014129:Trabecular Meshwork / Q000166:cytology* / Q000187:drug effects; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors
chemical_list: D000199:Actins; D000577:Amides; D000959:Antihypertensive Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D011725:Pyridines; D053778:Thiazolidines; C108830:Y 27632; D054460:rho-Associated Kinases; C037068:latrunculin B
keywords: Actin; Cytoskeleton; Latrunculin B; Rho-associated protein kinase; Trabecular Meshwork