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Reibel, S.

Publications and source records attributed to Reibel, S..

2 recordsLinked to original sources

Effects of bromodomain and extraterminal domain protein inhibition in a mouse model of Niemann-Pick type C disease

Defects in lysosomal lipid handling provoke fatal disorders presenting neurovisceral symptoms with variable onset and life spans. A prime example is Niemann-Pick type C disease (NPCD), where export of cholesterol and other lipids from the endosomal-lysosomal system is impaired due to variants of either NPC intracellular cholesterol transporter 1 (NPC1) or NPC intracellular cholesterol transporter 2 (NPC2). Therapeutic options for NPCD are limited to palliative care and disease-modifying drugs, and there is an unmet need for new treatments. Based on positive effects in patient-derived fibroblasts in vitro, we explored how inhibition of bromodomain and extra-terminal domain (BET) proteins affects a well-established mouse model bearing the frequent I1061T variant of NPC1. Treatment with JQ1, a hydrophobic prototype BET protein inhibitor, induced beneficial but sex-dependent molecular and behavioral changes in mice. Our results indicate bromodomain proteins as therapeutic drug target for NPCD and reveal sex-dependent BET protein signaling in mice.

neuroscience↗

Glial contribution to cyclodextrin-mediated reversal of cholesterol accumulation in murine NPC1-deficient neurons in vivo

Niemann-Pick type C (NPC) disease is a rare and fatal lysosomal storage disorder presenting severe neurovisceral symptoms. Disease-causing mutations in genes encoding either NPC1 or NPC2 protein provoke accumulation of cholesterol and other lipids in specific structures of the endosomal-lysosomal system and degeneration of specific cells, notably neurons in the central nervous system (CNS). 2-hydroxypropyl-beta-cyclodextrin (CD) emerged as potential therapeutic approach based on animal studies and clinical data, but the mechanism of action on neurons has remained unclear. To address this topic in vivo, we took advantage of the retina as highly accessible part of the (CNS) and intravitreal injections as mode of drug administration. We find that CD enters the endosomal-lysosomal system of neurons and enables the release of lipid-laden lamellar inclusions, which are then removed from the extracellular space by specific types of glial cells. Thus, CD triggers a concerted action of neurons and glial cells to restore lipid homeostasis in the central nervous system.

neuroscience↗