To explore the protective mechanism of Celosin Ⅰ on retinal ganglion cells by regulating reactive oxygen species (ROS) mediated mitochondrial apoptosis pathway.

Twenty-four New Zealand white rabbits were randomly divided into sham-operation, model, control and experimental groups, with 6 rabbits per group. The sham-operation group only had the bulbar conjunctiva cut and sutured, the other 3 groups were received with optic nerve clamp injury to contruct the optic nerve injury model. The sham-operation and model groups were given equal volumes of physiological saline by gavage, the control group was given a dose of 0.15 mg·kg^-1 mecobalamine solution by gavage, and the experimental group was given a dose of 30 mg·kg^-1 Celosin Ⅰ solution by gavage. Four groups were administered a daily gavage treatment for four consecutive weeks. The Tunnel method was used to detect apoptosis of retinal ganglion cells, and immunofluorescence was employed to detect the expression of ROS, superoxide dismutase (SOD) and caspase in retinal tissues. The expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-like protein 1 (Bcl-xl), Bcl-2-associated X protein (Bax), and cytochrome C (CytC) proteins in retinal tissues were assessed using Western blotting.

After four weeks of intervention, the apoptosis rates of ganglion cells in the experimental, control, model and sham-operated groups were (7.65±1.20)%, (11.65±1.29)%, (17.66±0.93)% and (0.97±0.14)%; the expression levels of ROS in retinal tissues were 6.14±0.57, 8.25±0.96, 16.51±1.07 and 2.05±0.23; the expression levels of SOD were 2.45±0.33, 1.48±0.23, 0.74±0.13 and 3.19±0.30; the expression levels of caspase-3 were 8.55±1.11, 12.68±0.92, 18.74±1.97 and 3.08±0.20; the expression levels of caspase-9 were 3.69±1.20, 7.79±1.13, 12.81±1.72 and 2.31±0.30; the relative expression levels of Bcl-2 were 0.46±0.02, 0.64±0.07, 0.77±0.05 and 0.20±0.03; the relative expression levels of Bcl-xl were 0.46±0.05, 0.61±0.05, 0.78±0.03, and 0.20±0.03; the relative expression levels of Bax were 0.50±0.07, 0.69±0.18, 0.82±0.13 and 0.14±0.04; the relative expression levels of CytC were 0.43±0.15, 0.80±0.14, 1.08±0.19 and 0.26±0.07. The differences in the aforementioned indicators in the experimental group compared with control group were statistically significant (all P<0.05).

Celosin Ⅰ reduces ROS levels in retinal tissue of a model of optic nerve injury, inhibits the expression of mitochondrial apoptosis related proteins in retinal ganglion cells, and reduces retinal ganglion cell apoptosis.