Browsing by Author "Wilms, Gerrit"

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Discovery of hydroxybenzothiazole urea compounds as multi-targeted agents suppressing major cytotoxic mechanisms in neurodegenerative diseases
(American Chemical Society, 11/02/2021) Aboushady, Youssef; Gabr, Moustafa; ElHady, Ahmed K; Salah, Mohamed; Abadi, Ashraf H; Wilms, Gerrit; Becker, Walter; Abdel-Halim, Mohammad; Engel, Matthias
Multiple factors are causally responsible and/or contribute to the progression of Alzheimer’s and Parkinson’s diseases. The protein kinase Dyrk1A was identified as a promising target as it phosphorylates tau protein, α-synuclein, and parkin. The first goal of our study was to optimize our previously identified Dyrk1A inhibitors of the 6-hydroxy benzothiazole urea chemotype in terms of potency and selectivity. Our efforts led to the development of the 3-fluorobenzyl amide derivative 16b, which displayed the highest potency against Dyrk1A (IC50 = 9.4 nM). In general, the diversification of the benzylamide moiety led to an enhanced selectivity over the most homologous isoform, Dyrk1B, which was a meaningful indicator, as the high selectivity could be confirmed in an extended selectivity profiling of 3b and 16b. Eventually, we identified the novel phenethyl amide derivative 24b as a triple inhibitor of Dyrk1A kinase activity (IC50 = 119 nM) and the aggregation of tau and α-syn oligomers. We provide evidence that the novel combination of selective Dyrk1A inhibition and suppression of tau and α-syn aggregations of our new lead compound confers efficacy in several established cellular models of neurotoxic mechanisms relevant to neurodegenerative diseases, including α-syn- and 6-hydroxydopamine-induced cytotoxicities.
Discovery of novel 6-hydroxybenzothiazole urea derivatives as dual Dyrk1A/α-synuclein aggregation inhibitors with neuroprotective effects
(Elsevier, 10/09/2021) AlNajjar, Yasmeen T; Gabr, Moustafa; ElHady, Ahmed K; Salah, Mohamed; Wilms, Gerrit; Abadi, Ashraf H; Becker, Walter; Abdel-Halim, Mohammad; Engel, Matthias
A role of Dyrk1A in the progression of Down syndrome–related Alzheimer's disease (AD) is well supported. However, the involvement of Dyrk1A in the pathogenesis of Parkinson's disease (PD) was much less studied, and it is not clear whether it would be promising to test Dyrk1A inhibitors in relevant PD models. Herein, we modified our previously published 1-(6-hydroxybenzo[d]thiazol-2-yl)-3-phenylurea scaffold of Dyrk1A inhibitors to obtain a new series of analogues with higher selectivity for Dyrk1A on the one hand, but also with a novel, additional activity as inhibitors of α-synuclein (α-syn) aggregation, a major pathogenic hallmark of PD. The benzyl acetamide derivative b27 displayed the highest potency against Dyrk1A with an IC50 of 20 nM and high selectivity over closely related kinases. Furthermore, b27 was shown to successfully target intracellular Dyrk1A and to inhibit SF3B1 phosphorylation in HeLa cells with an IC50 of 690 nM. In addition, two compounds among the Dyrk1A inhibitors, b1 and b20, also suppressed the aggregation of α-synuclein (α-syn) oligomers (with IC50 values of 10.5 μM and 7.8 μM, respectively). Both these compounds but not the Dyrk1A reference inhibitor harmine protected SH-SY5Y neuroblastoma cells against α-syn–induced cytotoxicity, with b20 exhibiting a higher neuroprotective effect. b1 and harmine were more efficient in protecting SH-SY5Y cells against 6-hydroxydopamine–induced cell death, an effect that was previously correlated to Dyrk1A inactivation in cells but not yet verified using chemical inhibitors. The presented dual inhibitors exhibited a novel activity profile encouraging for further testing in neurodegenerative disease models.