Figures
Hyperglycemia increases SCO-spondin and Wnt5a secretion into the cerebrospinal fluid to regulate ependymal cell beating and glucose sensing
Hyperglycemia increases glucose concentrations in the cerebrospinal fluid (CSF), activating glucose-sensing mechanisms and feeding behavior in the hypothalamus. Here, Nualart, Cifuentes et al. show how hyperglycemia temporarily modifies ependymal cell ciliary beating to increase hypothalamic glucose sensing. A high level of glucose in the rat CSF stimulates subcommissural organ (SCO) cells to release SCO-spondin into the dorsal third ventricle. In addition, SCO cells secrete Wnt5a-positive vesicles; thus, Wnt5a and SCO-spondin are found at the apex of dorsal ependymal cilia to regulate ciliary beating. The authors propose that the SCO-spondin/Wnt5a/Frizzled-2/Cx43 axis in ependymal cells regulates ciliary beating, a cyclic and adaptive signaling mechanism to control glucose sensing. The image shows scanning electron microscopy of dorsal third ventricle ependymal cells under hyperglycemic conditions, where the cilia appear rigid and perpendicular to the cell surface.
Image Credit: Paul San Martín and Francisco Nualart
Citation: (2023) PLoS Biology Issue Image | Vol. 21(9) October 2023. PLoS Biol 21(9): ev21.i09. https://doi.org/10.1371/image.pbio.v21.i09
Published: October 4, 2023
Copyright: © 2023 . This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Hyperglycemia increases glucose concentrations in the cerebrospinal fluid (CSF), activating glucose-sensing mechanisms and feeding behavior in the hypothalamus. Here, Nualart, Cifuentes et al. show how hyperglycemia temporarily modifies ependymal cell ciliary beating to increase hypothalamic glucose sensing. A high level of glucose in the rat CSF stimulates subcommissural organ (SCO) cells to release SCO-spondin into the dorsal third ventricle. In addition, SCO cells secrete Wnt5a-positive vesicles; thus, Wnt5a and SCO-spondin are found at the apex of dorsal ependymal cilia to regulate ciliary beating. The authors propose that the SCO-spondin/Wnt5a/Frizzled-2/Cx43 axis in ependymal cells regulates ciliary beating, a cyclic and adaptive signaling mechanism to control glucose sensing. The image shows scanning electron microscopy of dorsal third ventricle ependymal cells under hyperglycemic conditions, where the cilia appear rigid and perpendicular to the cell surface.
Image Credit: Paul San Martín and Francisco Nualart