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Heering, J.

Publications and source records attributed to Heering, J..

3 recordsLinked to original sources

Discovery of a new activator of Slack potassium channels with robust efficacy in models of histamine-independent and chronic itch

Various disorders are accompanied by histamine-independent itching, which is often resistant to the currently available therapies. In this study, we hypothesized that pharmacological activation of Slack (Kcnt1, KNa1.1), a potassium channel highly expressed in itch-sensitive sensory neurons, has therapeutic potential for the treatment of itching. Based on the Slack-activating antipsychotic drug, loxapine, we designed a series of new derivatives with improved pharmacodynamic and pharmacokinetic profiles that enabled us to validate Slack as a pharmacological target in vivo. One of these new Slack activators, compound 6, exhibited negligible dopamine D2 and D3 receptor binding, unlike loxapine. We found that compound 6 displayed potent on-target antipruritic activity in multiple mouse models of acute histamine-independent and chronic itch without motor side effects. These properties make compound 6 a lead molecule for the development of new antipruritic therapies targeting Slack.

pharmacology and toxicology↗

Targeting LC3/GABARAP for degrader development and autophagy modulation

Recent successes in developing small-molecule degraders that act through the ubiquitin system have spurred efforts to extend this technology to other mechanisms, including the autophagosomal-lysosomal pathway. Therefore, reports of autophagosome tethering compounds (ATTECs) have received considerable attention from the drug development community. ATTECs are based on the target recruitment to LC3/GABARAP, a family of membrane-bound proteins that tether autophagy receptors to the autophagosome. In order to validate the existing ligands, we rigorously tested target engagement of reported ATTEC ligands and handles. Surprisingly, using various biophysical methods, most available ligands did not interact with their designated target LC3. Intrigued by the idea of developing ATTECs, we evaluated the druggability of LC3/GABARAP by in silico docking and large scale crystallographic fragment screening. The data revealed that most fragments bound to the HP2, but not the HP1 pocket of the LC3-interacting region (LIR) docking site, suggesting favorable druggability of this binding pocket. Here, we present diverse comprehensively validated ligands for future ATTEC development.

biochemistry↗

Nurr1 modulation mediates neuroprotective effects of statins

The ligand-sensing transcription factor Nurr1 emerges as a promising therapeutic target for neurodegenerative pathologies but Nurr1 ligands for functional studies and therapeutic validation are lacking. Here we report pronounced Nurr1 modulation by statins for which clinically relevant neuroprotective effects have been demonstrated. Several statins directly affected Nurr1 activity in cellular and cell-free settings with low micromolar to sub-micromolar potencies. Simvastatin exhibited anti-inflammatory effects in astrocytes which were abrogated by Nurr1 knockdown. Differential gene expression analysis in native and Nurr1 silenced cells revealed strong proinflammatory effects of Nurr1 knockdown while simvastatin treatment induced several neuroprotective mechanisms via Nurr1, for example, in energy utilization and reduced apoptosis. These findings suggest Nurr1 involvement in the well-documented but mechanistically elusive neuroprotection by statins.

neuroscience↗