Bleomycin-Induced Trabecular Meshwork Senescence

Example 8

Administration of bleomycin, a DNA damaging agent, to the anterior chamber of the mouse or rabbit eye leads to cellular senescence, as detected by the induction of p16 transcript in the trabecular meshwork.

To induce a senescent phenotype in the trabecular meshwork in vivo, C57Bl/6 mice (aged 8 to 10 weeks) were injected intracamerally with 2 μL of 0.0075 U bleomycin sulfate. In the rabbit, 30 μL of 0.0075 U bleomycin sulfate were injected intracamerally in New Zealand white rabbits. Eyes were enucleated 14 days post-bleomycin injury and TM-enriched samples were micro-dissected. To determine change in senescent cells, RNA was isolated from TM and qPCR analysis was done to assess the effect of bleomycin on p16 mRNA levels.

FIGS. 12A and 12B show elevated relative expression of p16 at 14 days after intracameral (IC) injection of bleomycin in the right (OD) eye relative to the PBS-injected left (OS) eye of the test animals. This model can also be used to assess whether a test compound is pharmacologically capable of reducing or ameliorating the increased intraocular pressure that is a hallmark of primary open angle glaucoma (POAG).