Co-crystal structure determination and cellular evaluation of 1,4-dihydropyrazolo[4,3-c] [1,2] benzothiazine 5,5-dioxide p38α MAPK inhibitors

Desirée Bartolini; Mike Bührmann; Maria Letizia Barreca; Giuseppe Manfroni; Violetta Cecchetti; Daniel Rauh; Francesco Galli

doi:10.1016/j.bbrc.2019.02.063

Co-crystal structure determination and cellular evaluation of 1,4-dihydropyrazolo[4,3-c] [1,2] benzothiazine 5,5-dioxide p38α MAPK inhibitors

Biochem Biophys Res Commun. 2019 Apr 9;511(3):579-586. doi: 10.1016/j.bbrc.2019.02.063. Epub 2019 Feb 27.

Authors

Desirée Bartolini¹, Mike Bührmann², Maria Letizia Barreca³, Giuseppe Manfroni³, Violetta Cecchetti³, Daniel Rauh⁴, Francesco Galli³

Affiliations

¹ University of Perugia, Department of Pharmaceutical Sciences, Italy. Electronic address: desirex85@hotmail.it.
² TU Dortmund University, Faculty of Chemistry and Chemical Biology, Dortmund, Germany.
³ University of Perugia, Department of Pharmaceutical Sciences, Italy.
⁴ TU Dortmund University, Faculty of Chemistry and Chemical Biology, Dortmund, Germany. Electronic address: daniel.rauh@tu-dortmund.de.

PMID: 30824186
DOI: 10.1016/j.bbrc.2019.02.063

Abstract

p38α mitogen-activated protein kinase (MAPK) is an attracting pharmacological target in inflammatory diseases and cancer. Searching for new and more efficient p38-MAPK inhibitors, two recently developed pyrazolobenzothiazine-based (COXP4M12 and COXH11) compounds were investigated in this study using a cellular model of p38 activation. This consisted of HT29 human colorectal adenocarcinoma cells exposed to H₂O₂ or lipopolysaccharide (LPS). Immunoblot data confirmed the inhibitory effect of COXP4M12 and COXH11 on p38 substrate phosphorylation (MAPK-APK2 and ATF2 transcription factor). Compound cytotoxicity was very low and apparent efficacy of these inhibitors was comparable with that of SB203580, a commercially available type I inhibitor of p38. All these compounds also inhibit upstream kinases that promote p38-MAPK phosphorylation and co-activate the stress-activated protein kinase JNK, while ERK1/2 MAPK phosphorylation was unaffected. Compound-target kinase interaction was investigated by means of co-crystallization experiments that provided further structural and molecular insight on the inhibitory mechanism and optimization strategy of this new class of p38-MAPK inhibitors.

Keywords: ERK; HT-29 cells; MAPK inhibitors; Protein kinases; SAPK-JNK; p38-MAPK.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cell Line, Tumor
Crystallography, X-Ray
Humans
Mitogen-Activated Protein Kinase 14 / antagonists & inhibitors*
Mitogen-Activated Protein Kinase 14 / chemistry
Mitogen-Activated Protein Kinase 14 / metabolism*
Molecular Docking Simulation
Phosphorylation / drug effects
Protein Kinase Inhibitors / chemistry
Protein Kinase Inhibitors / pharmacology*
Pyrazoles / chemistry
Pyrazoles / pharmacology
Thiazines / chemistry
Thiazines / pharmacology*

Substances

Protein Kinase Inhibitors
Pyrazoles
Thiazines
Mitogen-Activated Protein Kinase 14