Role of ICAM-1 in impaired retinal circulation in rhegmatogenous retinal detachment

Impairment of flicker-induced increase in retinal blood flow in diabetic pigs

PURPOSE

To evaluate retinal blood flow (RBF) regulation in response to RBF stress in maturity-onset diabetes of the young type 3 (MODY3) pigs.

STUDY DESIGN

Case-control study.

METHODS

MODY3 pigs (diabetes mellitus [DM] group, n = 8) transfected with the human mutant hepatocyte nuclear factor-1⍺ and normal pigs of the same age (normal group, n = 8) were used as subjects. After confirming DM onset, the experiment was performed under inhalation anesthesia with isoflurane at 2 months of age before the cataract progressed. Ocular blood flow was assessed by calculating the optic papillary mean blur rate using laser speckle flowgraphy, modified for pig eye measurements. After baseline ocular blood flow measurements, flicker stimulation (12 Hz, 3 min) was applied, and ocular blood flow was measured over time.

RESULTS

Blood glucose was 81.8 ± 5.1 mg/dL in the normal group and 311.4 ± 23.1 mg/dL in the DM group (mean ± standard error). The percent change in ocular blood flow at 3 min after flicker stimulation was +31.0 ± 10.9% in the normal group and -6.6 ± 6.5% in the DM group compared to the preload value, and the difference was statistically significant (Mann-Whitney test, P = 0.015).

CONCLUSION

RBF response to flicker stimulation is reduced at 2 months of age in MODY3 pigs, suggesting that retinal neurovascular coupling is impaired from the early onset of DM.

Innate immune responsive inflammation in development of progressive myopia

PURPOSE

Inflammation has been implicated for development of myopia. It is not clear when inflammation is kicked in during the course of myopia, and what characteristics of the inflammation. In this study, we tested for cytokines from aqueous humour of eyes with wide spectrum of refractive status for profiling the inflammation.

METHODS

Aqueous humour of 142 patient eyes were tested for soluble intercellular adhesion molecule 1 (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), and transforming growth factor-beta 2 (TGF-β2) using an enzyme-linked immunosorbent assay (ELISA). Eye globe axial length of these patients ranged from emmetropia to high myopia.

RESULTS

Of 142 patients, an average axial length is 25.51 ± 3.31 mm, with a range of 21.56-34.37 mm. There are 36 cases in lower 25 percentile, 37 cases in upper 25 percentile, and 69 case in the middle 50 percentile. sICAM-1 and MCP-1 were significantly higher in the eyes with staphyloma (407.48 pg/mL, 312.31 pg/mL, n = 33) or macular schisis (445.86 pg/mL,345.33 pg/mL, n = 19) than that in the eyes without these changes (206.44 pg/mL, 244.76 pg/mL, n = 107). All three cytokines level was significantly associated with eye globe axial in a positive mode while adjusting for the age and sex. Strength of the association was the greatest for sICAM-1 and the weakest for TGF- β2. MCP-1 was in between.

CONCLUSION

sICAM-1 and MCP-1 in ocular fluid may be indicative biomarkers for progressive high myopia and the underneath autoimmune inflammation. sICAM-1 may be used as a monitoring biomarker for development of pathologic myopia.

Integrated bioinformatics analysis of retinal ischemia/reperfusion injury in rats with potential key genes

The tissue damage caused by transient ischemic injury is an essential component of the pathogenesis of retinal ischemia, which mainly hinges on the degree and duration of interruption of the blood supply and the subsequent damage caused by tissue reperfusion. Some research indicated that the retinal injury induced by ischemia-reperfusion (I/R) was related to reperfusion time.In this study, we screened the differentially expressed circRNAs, lncRNAs, and mRNAs between the control and model group and at different reperfusion time (24h, 72h, and 7d) with the aid of whole transcriptome sequencing technology, and the trend changes in time-varying mRNA, lncRNA, circRNA were obtained by chronological analysis. Then, candidate circRNAs, lncRNAs, and mRNAs were obtained as the intersection of differentially expression genes and trend change genes. Importance scores of the genes selected the key genes whose expression changed with the increase of reperfusion time. Also, the characteristic differentially expressed genes specific to the reperfusion time were analyzed, key genes specific to reperfusion time were selected to show the change in biological process with the increase of reperfusion time.As a result, 316 candidate mRNAs, 137 candidate lncRNAs, and 31 candidate circRNAs were obtained by the intersection of differentially expressed mRNAs, lncRNAs, and circRNAs with trend mRNAs, trend lncRNAs and trend circRNAs, 5 key genes (Cd74, RT1-Da, RT1-CE5, RT1-Bb, RT1-DOa) were selected by importance scores of the genes. The result of GSEA showed that key genes were found to play vital roles in antigen processing and presentation, regulation of the actin cytoskeleton, and the ribosome. A network included 4 key genes (Cd74, RT1-Da, RT1-Bb, RT1-DOa), 34 miRNAs and 48 lncRNAs, and 81 regulatory relationship axes, and a network included 4 key genes (Cd74, RT1-Da, RT1-Bb, RT1-DOa), 9 miRNAs and 3 circRNAs (circRNA_10572, circRNA_03219, circRNA_11359) and 12 regulatory relationship axes were constructed, the subcellular location, transcription factors, signaling network, targeted drugs and relationship to eye diseases of key genes were predicted. 1370 characteristic differentially expressed mRNAs (spec_24h mRNA), 558 characteristic differentially expressed mRNAs (spec_72h mRNA), and 92 characteristic differentially expressed mRNAs (spec_7d mRNA) were found, and their key genes and regulation networks were analyzed.In summary, we screened the differentially expressed circRNAs, lncRNAs, and mRNAs between the control and model groups and at different reperfusion time (24h, 72h, and 7d). 5 key genes, Cd74, RT1-Da, RT1-CE5, RT1-Bb, RT1-DOa, were selected. Key genes specific to reperfusion time were selected to show the change in biological process with the increased reperfusion time. These results provided theoretical support and a reference basis for the clinical treatment.

Comprehensive exploration of hub genes involved in oxidative stress in rhegmatogenous retinal detachment based on bioinformatics analysis

Rhegmatogenous retinal detachment (RRD) is a type of ophthalmologic emergency, if left untreated, the blindness rate approaches 100 %. The RRD patient postoperative recovery of visual function is unsatisfactory, most notably due to photoreceptor death. We conducted to identify the key genes for oxidative stress (OS) in RRD through bioinformatics analysis and clinical validation, thus providing new ideas for the recovery of visual function in RRD patients after surgery. A gene database for RRD was obtained from the Gene Expression Omnibus (GEO) database (GSE28133). Then we screened differentially expressed OS genes (DEOSGs) from the database and assessed the critical pathways in RRD with Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Protein-protein interaction (PPI) networks and hub genes among the common DEOSGs were identified. In addition, we collected general information and vitreous fluid from 42 patients with RRD and 22 controls [11 each of epiretinal membrane (EM) and macular hole (MH)], examined the expression levels of proteins encoded by hub genes in vitreous fluid by enzyme-linked immunosorbent assay (ELISA) to further assess the relationship between the ELISA data and the clinical characteristics of patients with RRD. Ten hub genes (CCL2, ICAM1, STAT3, CD4, ITGAM, PTPRC, CCL5, IL18, TLR2, VCAM1) were finally screened out from the dataset. The ELISA results showed that, compared with the control group, patients with RRD: TLR2 and ICAM-1 were significantly elevated, and CCL2 had a tendency to be elevated, but no statistically significant; RRD patients and MH patients compared with EM patients: STAT3 and VCAM-1 were significantly elevated. We found affected eyes of RRD patients compared with healthy eyes: temporal and nasal retinal nerve fiber layer (RNFL) were significantly thickened. By correlation analysis, we found that: STAT3 was negatively correlated with ocular perfusion pressure (OPP); temporal RNFL was not only significantly positively correlated with CCL2, but also negatively correlated with Scotopic b-wave amplitude. These findings help us to further explore the mechanism of RRD development and provide new ideas for finding postoperative visual function recovery.