Integrative study of gene expression datasets in retinal samples of Diabetic Retinopathy

PI3Kδ Mediates Fibrosis by Patient-Derived Vitreous

The epithelial-mesenchymal transition (EMT) is a fundamental process in developing fibrotic diseases, including forming epiretinal membranes (ERMs). ERMs can result in irreversible vision loss. Previous research has demonstrated that vitreous (VIT) derived from patients with proliferative diabetic retinopathy can stimulate angiogenesis through the Axl/PI3K/Akt pathway. Building upon this knowledge, we aimed to explore the influence of VIT from patients with macular membranes in ARPE-19 cells. Our findings reveal that patient-derived VIT from individuals with macular membranes promotes EMT and phosphoinositide 3-kinase-delta (PI3Kδ) expression in ARPE-19 cells. To elucidate the function of PI3Kδ in the ERM, we conducted experiments involving the knockout of p110δ, a key subunit of PI3Kδ, and observed that its absence hinders EMT induced by patient-derived VIT. Moreover, p110δ depletion reduces cell proliferation and migration in ARPE-19 cells. Remarkably, these effects were further corroborated by applying the p110δ inhibitor idelalisib, which blocks fibrosis in the laser-induced fibrosis model. Collectively, our results propose that p110δ plays a critical role in the progression of ERMs. Consequently, targeting p110δ emerges as a promising therapeutic approach for mitigating fibrosis. These findings contribute to a better understanding of the underlying mechanisms involved in ERM formation and highlight the potential for p110δ-directed antifibrotic therapy in retinal diseases.

Diabetes Reshapes the Circadian Transcriptome Profile in Murine Retina

Purpose

Diabetic retinopathy (DR) is a common complication of diabetes and has a high prevalence. Dysregulation of circadian rhythmicity is associated with the development of DR. This research aimed to investigate rhythmical transcriptome alterations in the retina of diabetic mice.

Methods

C57BL/6J mice were used to establish a diabetes model by intraperitoneal injection of streptozotocin (STZ). After 12 weeks, retinas were collected continuously at 4-hour intervals over 1 day. Total RNA was extracted from normal and STZ-treated retinas and RNA sequencing was performed. Meta2d algorithm, Kyoto Encyclopedia of Genes, Phase Set Enrichment Analysis, and time-series cluster analysis were used to identify, analyze and annotate the composition, phase, and molecular functions of rhythmic transcripts in retinas.

Results

The retina exhibited powerful transcriptome rhythmicity. STZ-induced diabetes markedly modified the transcriptome characteristics of the circadian transcriptome in the retina, including composition, phase, and amplitude. Moreover, the diabetic mice led to re-organized temporal and clustering enrichment pathways in space and time and affected core clock machinery.

Conclusions

Diabetes impairs the circadian rhythm of the transcriptomic profile of retinas. This study offers new perspectives on the negative effects of diabetes on the retina, which may provide important information for the development of new treatments for DR.