Objective To investigate the protective effects and possible mechanism of hydrogen sulfide (H2S) against oxidative stress injury induced by hydrogen peroxide (H2O2) in retinal ganglion cell-5 (RGC-5).Methods RGC-5 cells were divided into four groups:RGC-5 group (normal control group),RGC-5 + H2O2 (RGC-5 were cultured in 500 μmol · L-1 H2O2 for 24 hours) group,RGC-5 + NaHS (RGC-5 were cultured in 50 μmol · L-1 NaHS for 30 minutes) + H2O2 (RGC-5 were cultured in 500 μmol · L-1 H2 O2 for 24 hours) group,and RGC-5 + NaHS (RGC-5 were cultured in 50 μmol · L-1 NaHS for 30 minutes) group.Western blots were applied to measure the expression of cytochrome c (Cyt.c) and optic atrophy 1 (OPA1).The fluorescent dye JC-1 assay was chosen to detect the mitochondrial membrane potential (△Ψm).Furthermore,transmission electron microscope was used to observe the morphology of mitochondria.Results Compared with RGC-5 group,the expression of Cyt.c in RGC-5 + H2O2 group decreased in mitochondria,and increased in cytoplasm (all P ＜ 0.05),but there was no statistical difference between RGC-5 group and RGC-5 + NarHS + H2O2 group (all P ＞0.05).Compared with RGC-5 group,the expression of Cyt.c in RGC-5 + NaHS group increased in mitochondria,and decreased in cytoplasm (all P ＜ 0.05).Compared with RGC-5 group,the expression of OPA1 in RGC-5 + H2O2 group decreased in mitochondria,and increased in cytoplasm (all P ＜ 0.05).In RGC-5 + NaHs + H2O2 group and RGC-5 + NaHS group,the expression of OPA1 within and outside the mitochondria had no significant difference compared with RGC-5 group (all P ＞ 0.05).Compared with other three groups,the mitochondrial membrane potential in RGC-5 + H2O2 group obviously decreased,but there was no statistical difference among other three groups (P ＞ 0.05).The mitochondria were globular swelled in RGC-5 group,but in other three groups,the mitochondria had slightly swelled.Conclusion H2S can protect the mitochondrial morphology and functions of RGC? 5 from H2O2-induced oxidative stress via preventing OPA1 release from mitochondria.

Objective:To investigate the causes of secondary glaucoma after vitrectomy for familial vitreous amyloidosis associated with transthyretin (TTR) gene Gly83Arg mutation.Methods:A retrospective case study. From January 2008 to January 2020, 13 cases (23 eyes) with hereditary vitreous amyloidosis and treated by vitrectomy in the Affiliated Hospital of Zunyi Medical University were collected. Among them, there were 7 males with 12 eyes and 6 females with 11 eyes. The average age was 43.0±4.8 years. All the affected eyes underwent standard three-channel vitrectomy through the flat part of the ciliary body. According to whether complete vitreous detachment (PVD) was formed during the operation, it was divided into complete PVD group and incomplete PVD group; according to the occurrence time of secondary glaucoma and vitreous amyloidosis after surgery, it was divided into 1-12 months group and 13-36 months group, >37 months group. The average follow-up time after surgery was 36.7±6.0 months. The incidence of secondary glaucoma and the recurrence rate of vitreous amyloidosis between groups were compared by χ2 test; the correlation between recurrence of vitreous amyloidosis and secondary glaucoma after surgery was analyzed by Spearman rank correlation analysis. Results:Among the 23 eyes, there were 8 eyes in the complete PVD group and 15 eyes in the incomplete PVD group, respectively. Vitreous amyloidosis recurred in 15 eyes (65.22%, 15/23) after surgery. There were 14 (93.30%, 14/15) and 1 (6.70%, 1/15) eyes in the incomplete PVD group and the complete PVD group, respectively; the comparison of the recurrence rate of vitreous amyloidosis between the two groups was statistically significant ( χ2=11.676, P<0.01). 1-12 months group, 13-36 months group, >37 months group included 1 (4.35%, 1/23), 12 (52.17%, 12/23), 2 (8.70%, 2/23) Only eye. The recurrence rate in the 13-36 months group was significantly higher than that in the 1-12 months group and >37 month group. Secondary glaucoma occurred in 11 eyes (47.80%, 11/23) after surgery. 1-12 months group, 13-36 months group, above 37 months group were 1 (4.35%, 1/23), 8 (34.78%, 8/23), 2 (8.70%, 2/23) eyes. The incidence of secondary glaucoma in the 13-36 months group was higher than that in the 1-12 months group and >37 months group. Among 11 eyes with secondary glaucoma, 10 eyes had recurrence of vitreous amyloidosis after surgery, and 1 eye had no recurrence. The results of Spearman rank correlation analysis showed that there was a positive correlation between the recurrence of vitreous amyloidosis and the occurrence of secondary glaucoma ( rs=0.516, P=0.012). Conclusion:The incidence of secondary glaucoma after vitrectomy in a family with vitreous amyloidosis caused by the Gly83Arg mutation of TTR gene is higher, and its occurrence is significantly positively correlated with the recurrence of vitreous amyloidosis.