Objective: Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach. Here, we determined the corresponding activity profile of bakuchiol, a plant-derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
April 2022
SignificanceClassic serine proteases are synthesized as inactive precursors that are proteolytically processed, resulting in irreversible activation. We report an alternative and reversible mechanism of activation that is executed by an inactive protease. This mechanism involves a protein complex between the serine protease HTRA1 and the cysteine protease calpain 2.
View Article and Find Full Text PDFThe autophagic clearance of damaged lysosomes by lysophagy involves extensive modification of the organelle with ubiquitin, but the underlying ubiquitination machinery is still poorly characterized. Here, we use an siRNA screening approach and identify human UBE2QL1 as a major regulator of lysosomal ubiquitination, lysophagy, and cell survival after lysosomal damage. UBE2QL1 translocates to permeabilized lysosomes where it associates with damage sensors, ubiquitination targets, and lysophagy effectors.
View Article and Find Full Text PDFBackground: The ex vivo generation of human hematopoietic stem cells (HSCs) with long-term repopulating capacity and multi-lineage differentiation potential represents the holy grail of hematopoiesis research. In principle, human induced pluripotent stem cells (hiPSCs) provide the tool for both studying molecular mechanisms of hematopoietic development and the ex vivo production of 'true' HSCs for transplantation purposes and lineage-specific cells, e.g.
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