title: Potent trypanocidal curcumin analogs bearing a monoenone linker motif act on trypanosoma brucei by forming an adduct with trypanothione.
abstract: We have previously reported that curcumin analogs with a C7 linker bearing a C4-C5 olefinic linker with a single keto group at C3 (enone linker) display midnanomolar activity against the bloodstream form of Trypanosoma brucei. However, no clear indication of their mechanism of action or superior antiparasitic activity relative to analogs with the original di-ketone curcumin linker was apparent. To further investigate their utility as antiparasitic agents, we compare the cellular effects of curcumin and the enone linker lead compound 1,7-bis(4-hydroxy-3-methoxyphenyl)hept-4-en-3-one (AS-HK014) here. An AS-HK014-resitant line, trypanosomes adapted to AS-HK014 (TA014), was developed by in vitro exposure to the drug. Metabolomic analysis revealed that exposure to AS-HK014, but not curcumin, rapidly depleted glutathione and trypanothione in the wild-type line, although almost all other metabolites were unchanged relative to control. In TA014 cells, thiol levels were similar to untreated wild-type cells and not significantly depleted by AS-HK014. Adducts of AS-HK014 with both glutathione and trypanothione were identified in AS-HK014-exposed wild-type cells and reproduced by chemical reaction. However, adduct accumulation in sensitive cells was much lower than in resistant cells. TA014 cells did not exhibit any changes in sequence or protein levels of glutathione synthetase and γ-glutamylcysteine synthetase relative to wild-type cells. We conclude that monoenone curcuminoids have a different mode of action than curcumin, rapidly and specifically depleting thiol levels in trypanosomes by forming an adduct. This adduct may ultimately be responsible for the highly potent trypanocidal and antiparasitic activity of the monoenone curcuminoids.
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Abdulsalam A M
authors.initials: AA
authors.lastname: Alkhaldi
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Creek
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Hasan
authors.initials: H
authors.lastname: Ibrahim
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Neils B
authors.initials: NB
authors.lastname: Quashie
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Karl E
authors.initials: KE
authors.lastname: Burgess
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Chatchawan
authors.initials: C
authors.lastname: Changtam
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Michael P
authors.initials: MP
authors.lastname: Barrett
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.).
authors.forename: Apichart
authors.initials: A
authors.lastname: Suksamrarn
authors.affiliation: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom (A.A.M.A, D.J.C., H.I., D.-H.K., N.B.Q., K.E.B., M.P.B., H.P.K.); Department of Biology, College of Science, Aljouf University, Skaka, Kingdom of Saudi Arabia (A.A.M.A); Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia (D.J.C.); Faculty of Science, Department of Zoology, Sebha University, Libya (H.I.); Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom (D.-H.K.); Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana (N.B.Q.); Division of Physical Science, Faculty of Science and Technology, Huachiew Chalermprakiet University, Samutprakarn, Thailand (C.C.); Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom (M.P.B.); and Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, Thailand (A.S.) Harry.de-Koning@glasgow.ac.uk.
authors.forename: Harry P
authors.initials: HP
authors.lastname: de Koning
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D003474:Curcumin / Q000031:analogs & derivatives* / Q000378:metabolism* / Q000494:pharmacology; D005978:Glutathione / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D013095:Spermidine / Q000031:analogs & derivatives* / Q000378:metabolism; D014344:Trypanocidal Agents / Q000378:metabolism* / Q000494:pharmacology; D014346:Trypanosoma brucei brucei / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D014344:Trypanocidal Agents; C044809:trypanothione; D005978:Glutathione; D003474:Curcumin; D013095:Spermidine