Effect of ranibizumab on levels of IL-6 and VEGF in peripheral blood and aqueous humor of glaucoma rat model and association of IL-6 and VEGF with optic nerve damage

This study aims to investigate the effect of intravitreal injection of ranibizumab on glaucoma rat model and its effect on optic nerve injury. A total of 125 SD rats were used to establish glaucoma models. Of them, 80 well-established model were selected, 40 of which received intravitreal injections of ranibizumab and were assigned to the observation group. The remaining 40 received no drug and were assigned to the control group. After rats were sacrificed at the time-points, the retina was harvested. Numbers of retinal ganglion cells (RGCs) were counted under a fluorescence microscope. In the meantime, levels of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in peripheral blood and aqueous humor were determined. The levels of IL-6 and VEGF in peripheral blood and aqueous humor decreased gradually over the time of treatment in the observation group (P<0.05). In the control group the levels of IL-6 in peripheral blood and aqueous humor increased gradually over time (P<0.05). At the same time-point, the IL-6 level was higher in the control group than that in the observation group (P<0.05). The VEGF level in the observation group was lower in day 21 than that in day 7 (P<0.05). The VEGF level was higher in the control group than that in the observation group (P<0.05). The number of RGCs in the observation group increased gradually over the time of treatment, and there were significant differences in the number of RGCs between day 7 and 14, as well as day 14 and 21 (P<0.05). The number of RGCs in the control group decreased gradually over time (P<0.05). The levels of IL-6 and VEGF were all negatively correlated with the number of RGCs, and the correlation coefficient r and P-value were −0.743 and 0.012, and −0.675 and 0.022, respectively. Ranibizumab attenuated optic nerve injury by reducing levels of IL-6 and VEGF in peripheral blood and aqueous humor of glaucoma rat model.