Comparative Protective Effects of Anakinra and Tocilizumab in Experimental Ocular Ischemic Syndrome

Ocular ischemic syndrome (OIS) is a vision-threatening disorder characterized by retinal ischemia, oxidative stress, and inflammation. In this study, the protective effects of anakinra, an interleukin-1 receptor antagonist, were investigated and compared with those of tocilizumab, an interleukin-6 receptor antagonist. Twenty-four male Wistar rats were randomly assigned to four groups (n = 6 per group): sham-operated (SG), carotid artery clamping/unclamping (CUG), anakinra-treated carotid artery clamping/unclamping (ACUG), and tocilizumab-treated carotid artery clamping/unclamping (TCUG). An experimental ocular ischemic injury model induced by transient bilateral common carotid artery occlusion was established by transient bilateral common carotid artery clamping followed by reperfusion. Retinal tissues were analyzed for malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6) levels, and histopathological examinations were performed. OIS markedly increased MDA, TNF-α, IL-1β, and IL-6 levels while significantly decreasing tGSH, SOD, and CAT activities. Both anakinra and tocilizumab attenuated oxidative stress and inflammatory responses; however, anakinra produced notably greater improvements in MDA, tGSH, SOD, and CAT levels. Histopathological evaluation demonstrated that both treatments reduced retinal injury, edema, vascular congestion, and inflammatory cell infiltration. Although retinal architecture appeared slightly better preserved in the anakinra-treated group, histopathological scores were comparable between the treatment groups. These findings suggest that anakinra may attenuate oxidative and inflammatory retinal damage in this experimental ocular ischemic injury model and may provide greater biochemical protection than tocilizumab, whereas histopathological protection was comparable between treatments. Nevertheless, further experimental and clinical studies are required to confirm these findings. © 2026 by the authors.