Genome-Wide Identification of Circular RNAs as a Novel Class of Putative Biomarkers for an Ocular Surface Disease.

BACKGROUND/AIMS: Pterygium is a common ocular surface disease with an unknown etiology and threatens vision as it invades into the cornea. Circular RNAs (circRNAs) are a novel class of RNA transcripts that participate in several physiological and pathological processes. However, the role of circRNAs in pathogenesis of pterygium remains largely unknown. METHODS: Genome-wide circRNA expression profiling was performed to identify pterygium -related circRNAs. GO analysis, pathway analysis, and miRNA response elements analysis was performed to predict the function of differentially expressed circRNAs in pterygium. MTT assays, Ki67 staining, Transwell assay, Hoechst 33342 staining, and Calcein-AM/PI staining were performed to determine the effect of circRNA silencing on pterygium fibroblast and epithelial cell function. RESULTS: Approximately 669 circRNAs were identified to be abnormally expressed in pterygium tissues. GO analysis demonstrated that the host genes of differentially expressed circRNAs were targeted to extracellular matrix organization (ontology: biological process), cytoplasm (ontology: cellular component), and protein binding (ontology: molecular function). Pathway analysis showed that dysregulated circRNAs-mediated regulatory networks were mostly enriched in focal adhesion signaling pathway. Notably, circ_0085020 (circ-LAPTM4B) was shown as a potential biomarker for pterygium. circ_0085020 (circ-LAPTM4B) silencing affected the viability, proliferation, migration, and apoptosis of pterygium fibroblast and epithelial cells in vitro. CONCLUSIONS: This study provides evidence that circRNAs are involved in the pathogenesis of pterygium and might constitute promising targets for the therapeutic intervention of pterygium.

Long non-coding RNA MEG3 silencing protects against light-induced retinal degeneration.

Excessive light exposure leads to retinal degeneration and accelerates the progression and severity of several ocular diseases, such as age-related macular degeneration (AMD) and retinitis pigmentosa. Long non-coding RNAs (LncRNAs) have emerged as important regulators of photoreceptor development and ocular diseases. In this study, we investigated the role of lncRNA-MEG3 in light-induced retinal degeneration. MEG3 expression was significantly up-regulated after light insult in vivo and in vitro. MEG3 silencing protected against light-induced retinal degeneration in vivo and light-induced photoreceptor cell apoptosis in vitro. Mechanistically, MEG3 regulated retinal photoreceptor cell function by acting as p53 decoy. MEG3 silencing decreased caspase 3/7 activity, up-regulated anti-apoptotic protein (Bcl-2) expression, and down-regulated pro-apoptotic protein (Bax) expression. Taken together, this study provides a promising method of MEG3 silencing for treating light-induced retinal degeneration.

Parabrachial nucleus astrocytes regulate wakefulness and isoflurane anesthesia in mice.

Background: The parabrachial nucleus (PBN) is an important structure regulating the sleep-wake behavior and general anesthesia. Astrocytes in the central nervous system modulate neuronal activity and consequential behavior. However, the specific role of the parabrachial nucleus astrocytes in regulating the sleep-wake behavior and general anesthesia remains unclear. Methods: We used chemogenetic approach to activate or inhibit the activity of PBN astrocytes by injecting AAV-GFAabc1d-hM3Dq-eGFP or AAV-GFAabc1d-hM4Di-eGFP into the PBN. We investigated the effects of intraperitoneal injection of CNO or vehicle on the amount of wakefulness, NREM sleep and REM sleep in sleep-wake behavior, and on the time of loss of righting reflex, time of recovery of righting reflex, sensitivity to isoflurane, electroencephalogram (EEG) power spectrum and burst suppression ratio (BSR) in isoflurane anesthesia. Results: The activation of PBN astrocytes increased wakefulness amount for 4 h, while the inhibition of PBN astrocytes decreased total amount of wakefulness during the 3-hour post-injection period. Chemogenetic activation of PBN astrocytes decreased isoflurane sensitivity and shortened the emergence time from isoflurane-induced general anesthesia. Cortical EEG recordings revealed that PBN astrocyte activation decreased the EEG delta power and BSR during isoflurane anesthesia. Chemogenetic Inhibition of PBN astrocytes increased the EEG delta power and BSR during isoflurane anesthesia. Conclusion: PBN astrocytes are a key neural substrate regulating wakefulness and emergence from isoflurane anesthesia.