We investigated the effect of > or = 8 months of 40% caloric restriction (CR) on photoreceptor cell loss in 12, 18, and 24 month-old Fischer 344 rats (N = 154). Rats were reared at the NIA Biomarkers Program, National Center for Toxicological Research. Photoreceptor cell density, assessed histologically, declined with age in both the CR-fed and ad lib (AL)-fed cohorts (P < 0.000), but declines were more pronounced in the CR cohort (P < 0.0005). The deleterious effect of CR was most pronounced in the central as opposed to the peripheral retina (P = 0.008), suggesting a light-dependent mechanism. Photoreceptor cell density was inversely associated with rearing under bright light (300-750 lux) as compared with rearing under lower illuminance (< or = 200 lux) (P < 0.0005). However, the deleterious effect of bright light on photoreceptor cell density was more pronounced in the CR cohort (P = 0.04). Effects of CR on circadian activity are likely to increase the actual light exposure of the CR cohort and may explain the apparent inability of CR to delay retinal aging in albino rats.
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Turk J Ophthalmol
January 2025
İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, Department of Ophthalmology, İstanbul, Türkiye.
Jeune syndrome (JS), first described by Jeune as asphyxiating thoracic dystrophy, is an autosomal recessive osteochondrodysplasia with characteristic skeletal abnormalities and variable renal, hepatic, pancreatic, and ocular complications. Approximately 1 in every 100,000 to 130,000 babies is born with JS. Most patients with JS have respiratory distress due to inadequate lung development and many lose their lives due to respiratory failure.
View Article and Find Full Text PDFJ Struct Biol
January 2025
Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, CA 92697, USA; Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA. Electronic address:
Arrestins halt cell signaling by binding to phosphorylated activated G protein-coupled receptors. Arrestin-1 binds to rhodopsin, arrestin-4 binds to cone opsins, and arrestins-2,3 bind to the rest of GPCRs. In addition, it has been reported that arrestin-1 is functionally expressed in mouse cone photoreceptors.
View Article and Find Full Text PDFCell Insight
February 2025
Eye Center, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei, China.
Retinal degenerative diseases encompass a diverse range of eye conditions that result in blindness, many due to photoreceptor dysfunction and loss. Regrettably, current clinical treatments are frequently not overly effective. However, photoreceptor transplantation shows promise as a potential therapy for late-stage retinal degenerative diseases.
View Article and Find Full Text PDFMol Ther Nucleic Acids
March 2025
Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy.
Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous disorders characterized by progressive photoreceptor degeneration and irreversible vision loss. MicroRNAs (miRNAs), a class of endogenous non-coding RNAs with post-transcriptional regulatory properties, are known to play a major role in retinal function, both in physiological and pathological conditions. Given their ability to simultaneously modulate multiple molecular pathways, miRNAs represent promising therapeutic tools for disorders with high genetic heterogeneity, such as IRDs.
View Article and Find Full Text PDFPreviously we reported color matches measured in young adults using a newly developed multi-wavelength LED-based visual trichromator with which we estimated their individual L-, M- and S-cone spectral sensitivities. Here, we extend those measurements to include 70 additional observers aged between 8 to 80 years. As in our previous work, a series of color matching measurements were made to a reference white.
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