The modulating of Qingguang’anⅡFormula on gut microbiota in mice with chronic high intraocular pressure by 16S rDNA sequencing

Objective To investigate the effects of Qingguang'anⅡFormula(QGAⅡ)on the gut micro-biota of mice with chronic high intraocular pressure(IOP)model,and explore its key micro-biota for protecting the optic nerve.Methods A total of 10 specific pathogen free(SPF)grade female DBA/2J mice were random-ly divided into model group and QGAⅡgroup(n=5 for each group),while additional 5 SPF-grade female C57BL/6J mice were assigned to control group.Mice presented spontaneous high IOP and showed elevated approximately at the age of seven months.The high IOP was maintained until week 38,when gavage was initiated.Mice in control group underwent the same intragastric treatment,while those in QGAⅡgroup were gavaged with QGAⅡ(9.67 g/kg),once a day for four weeks.Retinal morphology was examined using hematoxylin and eosin(HE)staining,with the number of retinal ganglion cells(RGCs)counted.The expression level of Brn3a protein,a specific marker for RGCs,was detected by immunofluorescence,with the mean optical density(OD)measured for quantitative analysis.In addition,16S rDNA se-quencing was leveraged to analyze changes in the diversity of gut microbiota,including theirα-diversity(Chao1,Shannon,Pielou’s evenness,and observed species index)andβ-diversity.Venn diagrams and linear discriminant analysis effect size(LEfSe)analysis was employed to investigate the number of amplicon sequence variants(ASVs),the abundance of differential gut microbiota species,and the classification of species at both the phylum and genus levels within the three groups of mice.Results HE staining revealed that compared with control group,model group showed signif-icant reduction in the number of RGCs(P<0.01),with intracellular vacuolar degeneration and nuclear pyknosis.After QGAⅡtreatment,the number of RGCs was significantly in-creased compared with model group(P<0.01),with notable improvements in intracellular vacuolar degeneration.Immunofluorescence analysis showed that the mean OD of Brn3a protein was significantly decreased in model group compared with control group(P<0.01),while QGAⅡtreatment significantly elevated its expression level(P<0.01).Analysis ofα-diversity showed that after QGAⅡintervention,the Chao1,Shannon,and Pielou’s evenness indices were significantly increased(P<0.01),and the observed species index was elevated(P<0.05).β-Diversity analysis demonstrated distinct clustering among the three groups,indicating relatively low similarity in bacterial community structures.ASV clustering identi-fied a total of 14061 ASVs across all groups,with 9514 ASVs shared between model and QGAⅡgroups.At the phylum level,the abundance of Bacteroidetes was significantly decreased in model group compared with control group(P<0.01),while Firmicutes and the Firmicutes/Bacteroidetes(F/B)ratio were significantly increased(P<0.01).QGAⅡtreatment significantly reduced both Firmicutes abundance and the F/B ratio(P<0.01).At the genus level,Lactobacillus was dominant across all groups,with its abundance significantly in-creased in model group(P<0.01)and subsequently decreased following QGAⅡintervention(P<0.05).Conclusion QGAⅡrestructured the gut microbiota of DBA/2J mice with chronic high IOP,bringing changes in their diversity and abundance of components.Firmicutes,Bacteroidetes,Lactobacillus,along with their associated microorganisms,are likely critical components of the gut microbiota that contribute to the optic neuroprotective effects of QGAⅡon chronic high IOP mice.

Effect on multifocal electroretinogram in persistently elevated intraocular pressure by erigeron breviscapus extract

AIM: To observe the effect on multifocal electroretinogram (mfERG) in persistently elevated intraocular pressure (TOP) by erigeron breviscapus extract (also named Dengzhanhua in Chinese) in rat models. METHODS: The rat models with persistently elevated TOP were established by the method of Akira. Then, erigeron breviscapus extract was given for one month to observe the effect on mfERG in persistently elevated TOP in rats. RESULTS: As elevated TOP went on, the mfERG changes were mainly in weaken of reaction density with progressive development. After intervention of erigeron breviscapus extract, the total peak latency of 131 wave had recovered to some extent and the difference was significant when compared with control group (P <0.05); the total response density and P1 wave response density in second circle had risen noticeably, which had significant differences than those of control group (P <0.05). CONCLUSION: Erigeron breviscapus extract can improve the impaired visual function of persistently elevated TOP in rats, suggesting that this extract is the effective part of erigeron breviscapus for optic neuroprotection.