Induction of age-related ocular disorders in a mouse model of pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease linked to aging. This study investigates potential connections between IPF and age-related eye problems using a bleomycin-induced IPF mouse model. Intratracheal administration of bleomycin induces rapid lung injury in mice, followed by IPF with characteristics of cellular senescence. IPF-injured mice had reduced amplitudes of scotopic ERG and immunostaining of visual arrestin, suggesting declined rod-related visual function. Interestingly, the mice's eyes also showed increased susceptibility to Staphylococcus aureus infections, reminiscent of the aging eyes. To determine whether an early onset of aging contributes to the eye disorders, we examined complement and senescence markers in the retina. In bleomycin-injury IPF mice, DNA damage-related senescence marker γH2AX was found in the retinal out nuclear layer where photoreceptors are located. Additionally, IPF mice displayed elevated levels of C3b, a complement fragment resulting from C3 activation that occurs frequently in aging eyes. These findings underscore the potential of IPF as a valuable mouse model for investigating early-onset age-related ocular disorders.