title: Inhibitory effects of Aphanizomenon flos-aquae constituents on human UDP-glucose dehydrogenase activity.
abstract: OBJECTIVE
  The purpose of this study was to investigate the in vitro inhibitory effects of the edible microalga Aphanizomenon flos-aquae (AFA) on human UDP-α-d-glucose 6-dehydrogenase (UGDH) activity, a cytosolic enzyme involved both in tumor progression and in phytochemical bioavailability.
  
  
  METHODS
  Both the hydrophilic and ethanolic AFA extracts as well as the constitutive active principles phycocyanin (PC), phycocyanobilin (PCB) and mycosporine-like amino acids (MAAs) were tested.
  
  
  RESULTS
  Among AFA components, PCB presented the strongest inhibitory effect on UGDH activity, acting as a competitive inhibitor with respect to UDP-glucose and a non-competitive inhibitor with respect to NAD(+). In preliminary experiments, AFA PCB was also effective in reducing the colony formation capacity of PC-3 prostate cancer cells and FTC-133 thyroid cancer cells.
  
  
  CONCLUSIONS
  Overall, these findings confirmed that AFA and its active principles are natural compounds with high biological activity. Further studies evaluating the effects of AFA PCB in reducing tumor cell growth and phytochemical glucuronidation are encouraged.
authors.affiliation: a Nutritherapic Research Center , Urbino , Italy and.
authors.forename: Stefano
authors.initials: S
authors.lastname: Scoglio
authors.affiliation: b Department of Biomolecular Sciences , University of Urbino "Carlo Bo" , Urbino , Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Lo Curcio
authors.affiliation: b Department of Biomolecular Sciences , University of Urbino "Carlo Bo" , Urbino , Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Catalani
authors.affiliation: b Department of Biomolecular Sciences , University of Urbino "Carlo Bo" , Urbino , Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Palma
authors.affiliation: b Department of Biomolecular Sciences , University of Urbino "Carlo Bo" , Urbino , Italy.
authors.forename: Serafina
authors.initials: S
authors.lastname: Battistelli
authors.affiliation: b Department of Biomolecular Sciences , University of Urbino "Carlo Bo" , Urbino , Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Benedetti
mesh_terms: D046890:Aphanizomenon / Q000737:chemistry*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D008297:Male; D014533:Uridine Diphosphate Glucose Dehydrogenase / Q000037:antagonists & inhibitors*
chemical_list: D004791:Enzyme Inhibitors; D014533:Uridine Diphosphate Glucose Dehydrogenase
keywords: Klamath algae; phycocyanin; phycocyanobilin; tumor cell growth inhibition