title: Trilobolide-porphyrin conjugates: on synthesis and biological effects evaluation.
abstract: Trilobolide (Tb), a potent natural counterpart of thapsigargin, is a sesquiterpene lactone of guaianolide type isolated from horse caraway (Laser trilobum, L. Borkh). Tb exerts remarkable pharmacological properties based on irreversible inhibition of sarco/endoplasmic reticulum calcium ATPase (SERCA), thus being of increasing interest for cancer cure. Additionally, another pharmacological activity of Tb, as well as of thapsigargin, was reported in several studies, Tb as being an effective inductor of nitric oxide and cytokine production. These extraordinary biological properties move these molecules in further pre-clinical evaluation. Because of ubiquitous character of SERCA expression, development of specifically targeted bioactive molecules is inevitable. Since it is well known that porphyrins are preferentially taken up by cancer cells, we have designed and synthesized novel Tb-porphyrin conjugates. Copper-catalyzed azide-alkyne cycloaddition was used to link Tb with porphyrin at once. Two model conjugates of Tb and porphyrin were synthesized and properly characterized. Employing naturally occurring fluorescence properties of porphyrins, we investigated the intracellular localization of the conjugates employing fluorescence microscopy in living cells. Intriguingly, the prepared conjugates localized both in mitochondria and lysosomes of HeLa and LNCaP cells. Furthermore, the cytotoxicity of Tb-porphyrin conjugates was assessed in a number of human cancer cell lines and rat peritoneal cells. Likewise in cancer cell lines, viability of rat peritoneal cells was not affected by the tested conjugates. Interestingly, we observed dose-dependent nitric oxide (iNOS) production induced by the tested conjugates. The effect was related to the type of a linker used and the overall size of the molecule. Another potent immunobiological effects are under evaluation. In summary, the results presented here indicate notable immunobiological potential of the prepared Tb conjugates. Moreover, they could help to decipher the molecular mechanism of Tb for its possible biomedical applications.
authors.affiliation: Department of Chemistry of Natural Compounds, Institute of Chemical Technology in Prague, CZ-16628 Prague, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Tomanová
authors.affiliation: Department of Biochemistry and Microbiology, Institute of Chemical Technology in Prague, CZ-166 28 Prague, Czech Republic.
authors.forename: Silvie
authors.initials: S
authors.lastname: Rimpelová
authors.affiliation: Department of Chemistry of Natural Compounds, Institute of Chemical Technology in Prague, CZ-16628 Prague, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Jurášek
authors.affiliation: Institute of Organic Chemistry and Biochemistry, CZ-166 10 Prague, Czech Republic.
authors.forename: Miloš
authors.initials: M
authors.lastname: Buděšínský
authors.affiliation: Institute of Pharmacology and Toxicology and Biomedical Centre, Faculty of Medicine in Pilsen, Charles University in Prague, CZ-301 66 Pilsen, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Vejvodová
authors.affiliation: Department of Biochemistry and Microbiology, Institute of Chemical Technology in Prague, CZ-166 28 Prague, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Ruml
authors.affiliation: Institute of Pharmacology and Toxicology and Biomedical Centre, Faculty of Medicine in Pilsen, Charles University in Prague, CZ-301 66 Pilsen, Czech Republic. Electronic address: eva.kmonickova@lfp.cuni.cz.
authors.forename: Eva
authors.initials: E
authors.lastname: Kmoníčková
authors.affiliation: Department of Chemistry of Natural Compounds, Institute of Chemical Technology in Prague, CZ-16628 Prague, Czech Republic. Electronic address: pavel.drasar@vscht.cz.
authors.forename: Pavel B
authors.initials: PB
authors.lastname: Drašar
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002087:Butyrates / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D005663:Furans / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008968:Molecular Conformation; D009569:Nitric Oxide / Q000096:biosynthesis; D011166:Porphyrins / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D002087:Butyrates; D005663:Furans; D011166:Porphyrins; D009569:Nitric Oxide; C086352:trilobolide
keywords: Fluorescence microscopy; Nitric oxide; Porphyrin; Trilobolide