Sodium Iodate-Induced Degeneration Results in Local Complement Changes and Inflammatory Processes in Murine Retina

• Published in: International journal of molecular sciences 2021-08, Vol.22 (17), p.9218
• Main Authors: Enzbrenner, Anne, Zulliger, Rahel, Biber, Josef, Pousa, Ana Maria Quintela, Schäfer, Nicole, Stucki, Corinne, Giroud, Nicolas, Berrera, Marco, Kortvely, Elod, Schmucki, Roland, Badi, Laura, Grosche, Antje, Pauly, Diana, Enzmann, Volker
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis; Apoptosis - genetics; Apoptosis - immunology; Atrophy; Blindness; Chemokines; Complement; Complement component C1s; Complement component C3; Complement component C4; Complement System Proteins - genetics; Complement System Proteins - immunology; Complement System Proteins - metabolism; Cytokines; Disease Models, Animal; Disease Susceptibility; Enzyme-linked immunosorbent assay; Epithelium; Fluorescent Antibody Technique; Gene Expression Regulation - drug effects; geographic atrophy; IL-1β; Immune system; Immunity, Innate; Immunohistochemistry; Inflammation; innate immunity; Iodates - adverse effects; local complement; Macrophages; Macular degeneration; Mice; Microglia; Mueller cells; Oxidative stress; Photoreceptors; Proteins; Retina; Retinal degeneration; Retinal Degeneration - etiology; Retinal Degeneration - metabolism; Retinal Degeneration - pathology; Retinal pigment epithelium; Sodium; sodium iodate; Transcription; Vascular endothelial growth factor
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms22179218

Age-related macular degeneration (AMD), one of the leading causes of blindness worldwide, causes personal suffering and high socioeconomic costs. While there has been progress in the treatments for the neovascular form of AMD, no therapy is yet available for the more common dry form, also known as geographic atrophy. We analysed the retinal tissue in a mouse model of retinal degeneration caused by sodium iodate (NaIO )-induced retinal pigment epithelium (RPE) atrophy to understand the underlying pathology. RNA sequencing (RNA-seq), qRT-PCR, Western blot, immunohistochemistry of the retinas and multiplex ELISA of the mouse serum were applied to find the pathways involved in the degeneration. NaIO caused patchy RPE loss and thinning of the photoreceptor layer. This was accompanied by the increased retinal expression of complement components , , and . C1s, C3, CFH and CFB were complement proteins, with enhanced deposition at day 3. C4 was upregulated in retinal degeneration at day 10. Consistently, the transcript levels of proinflammatory , , , , and were increased in the retinas of NaIO mice, but mRNA was reduced. Macrophages, microglia and gliotic Müller cells could be a cellular source for local retinal inflammatory changes in the NaIO retina. Systemic complement and cytokines/chemokines remained unaltered in this model of NaIO -dependent retinal degeneration. In conclusion, systemically administered NaIO promotes degenerative and inflammatory processes in the retina, which can mimic the hallmarks of geographic atrophy.