PFKFB3 knockdown attenuates Amyloid β-Induced microglial activation and retinal pigment epithelium disorders in mice

• Published in: International immunopharmacology 2023-02, Vol.115, p.109691-109691, Article 109691
• Main Authors: Wang, Yusong, Han, Siyang, Chen, Jieqiong, Sun, Junran, Sun, Xiaodong
• Format: Article
• Language: English
• Subjects: Age-related macular degeneration; Amyloid beta-Peptides - metabolism; Animals; Macular Degeneration - genetics; Metabolic reprogramming; Mice; Microglia; Neuroinflammatory cytokines; Neuroinflammatory Diseases; Retina - pathology; Retinal Pigment Epithelium
• ISSN: 1567-5769; 1878-1705
• DOI: 10.1016/j.intimp.2023.109691

•Intravitreal injection of oligomeric Amyloid β can cause retinal inflammatory microenvironment.•Inflammatory cytokines are reduced by activated microglia in retina.•Activated microglia and released inflammatory cytokines results in retinal pigment epithelium (RPE) disorders.•PFKFB3 knockdown attenuates Aβ-Induced microglial activation and RPE disorders. Age-related macular degeneration (AMD) is characterized by progressive accumulation of drusen deposits and retinal pigment epithelium (RPE) disorders. As the main component of drusen, amyloid β (Aβ) plays a critical role in activating microglia and causing neuroinflammation in AMD pathogenesis. However, the role of activated microglia-mediated neuroinflammation in RPE senescence remains unclear. Recent evidence indicates that inflammatory microglia are glycolytic and driven by an increase in 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), an enzyme described as the master regulator of glycolysis. In this study, we mimicked the retinal inflammatory microenvironment of AMD by intravitreal injection of oligomeric Aβ1-40 in mice, which resulted in activation of microglia and upregulation of PFKFB3. RNA sequencing was performed to evaluate PFKFB3-mediated microglial activation. The effect of microglial activation on RPE disorders was assessed using gene knockout experiments, immunofluorescence, CCK-8 assay, and β-galactosidase staining. Intravitreal Aβ1-40 injection induced proinflammatory activation of microglia by upregulating PFKFB3 and resulted in RPE disorders, which was verified in heterozygous Pfkfb3-deficient mice (Pfkfb3+/-) mice, Aβ1-40-activated microglial cell line BV2, and co-culture of RPE cell line ARPE19. RNA sequencing revealed that PFKFB3 mainly affected innate immune processes during Aβ1-40-induced retinal inflammation. PFKFB3 knockdown inhibited RPE disorders and rescued the retinal structure and function. Overall, the modulation of PFKFB3-mediated microglial glycolysis and activation is a promising strategy for AMD treatment.