Single-cell profiling reveals Müller glia coordinate retinal intercellular communication during light/dark adaptation via thyroid hormone signaling

Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination. Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation. However, various types of neurons and glial cells exist in the retina, and whether and how all retinal cells interact to adapt to light/dark conditions at the cellular and molecular levels requires systematic investigation. Therefore, we utilized single-cell RNA sequencing to dissect retinal cell-type-specific transcriptomes during light/dark adaptation in mice. The results demonstrated that, in addition to photoreceptors, other retinal cell types also showed dynamic molecular changes and specifically enriched signaling pathways under light/dark adaptation. Importantly, Müller glial cells (MGs) were identified as hub cells for intercellular interactions, displaying complex cell‒cell communication with other retinal cells. Furthermore, light increased the transcription of the deiodinase Dio2 in MGs, which converted thyroxine (T4) to active triiodothyronine (T3). Subsequently, light increased T3 levels and regulated mitochondrial respiration in retinal cells in response to light conditions. As cones specifically express the thyroid hormone receptor Thrb, they responded to the increase in T3 by adjusting light responsiveness. Loss of the expression of Dio2 specifically in MGs decreased the light responsive ability of cones. These results suggest that retinal cells display global transcriptional changes under light/dark adaptation and that MGs coordinate intercellular communication during light/dark adaptation via thyroid hormone signaling.

Comparison of kidney tubular epithelial cells and endothelial cells grown on titania nanotubes / 中华肾脏病杂志

Objective To observe the adhesion and growth of LLC-PK1 cells and ECV304 cells on titania nanotube arrays, and provide evidence for construction of miniaturation bioartificial kidney. Methods Four different diameters nanotube materials were prepared by anodic oxidation, each material was processed by unannealed and with UV irradiation, annealed and without UV irradiation, annealed and with UV irradiation, respectively, which had 12 groups totally,then two kinds of cells were separately grown on the 12 materials. The adhesion and growth of the two kinds of cells were studied under a fluorescence microscope. MTT assay was used to test the activity of two kinds of cells on different diameters and the proliferation of two kinds of cells on 70 nm diameters. Results The adhesion and proliferation of two kinds of cells on TiO2 nanotube arrays were basically consistent, both on anatase TiO2 nanotubes with 70 nm diameter but without UV irradiation showed the optimal adhesion and activity. The activities of LLC-PK1 cells and ECV304 cells were both increased with time extended, while the absorbance of ECV304 cells was higher on pure Ti film than on titania nanotube. Conclusion TiO2 nanotube is beneficial to LLC-PK1 cells, but is unfavorable for ECV304 cells when they grow alone.