title: Anti-proliferative and antibacterial in vitro evaluation of the polyurethane nanostructures incorporating pentacyclic triterpenes.
abstract: BACKGROUND
  Oleanolic and ursolic acids are antitumor and antibacterial agents which are extensively studied. Their major disadvantage is the poor water solubility which limits their applications.
  
  
  OBJECTIVE
  Oleanolic and ursolic acid were encapsulated into polyurethane nanostructures that act as drug carriers. In order to evaluate the effectiveness of the particles, anti-microbial and anti-proliferative activity compared to un-encapsulated active compounds was tested.
  
  
  METHODS
  Using an interfacial polycondensation technique, combined with spontaneous emulsification, structures with nanoscale dimensions were obtained. Scanning electron microscopy, differential scanning calorimetry and X-ray assays confirmed the encapsulation process. Concentrations of 10 and 30 μM particles and un-encapsulated compounds were tested by MTT viability assay for several breast cancer lines, with an exposure time of 72 h. For the antibacterial studies, the dilution method with MIC determination was used.
  
  
  RESULTS
  Ursolic acid had an excellent inhibitory effect with IC50value of 2.47, 1.20, 1.26 and 1.34 μM on MCF7, T47D, MDA-MB-231 and MDA-MB-361, respectively. Oleanolic acid did not show anti-proliferative activity. The pure compounds showed their antibacterial activity only against Bacillus species and Candida albicans, but MIC values were too high to be considered efficient antimicrobial agents (2280 and 4570 μg mL-1, respectively). Polyurethane nanoparticles which incorporated the agents did not show any biological activity.
  
  
  CONCLUSIONS
  Although the active compounds did not fully exert their anti-proliferative activity following encapsulation inside polymeric nanoparticles, in vivo evaluation is needed in order to obtain an exhaustive conclusion, as the active compounds could be released as a result of metabolic activity.
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Camelia
authors.initials: C
authors.lastname: Oprean
authors.affiliation: b Faculty of Medicine , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Csilla
authors.initials: C
authors.lastname: Zambori
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Florin
authors.initials: F
authors.lastname: Borcan
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Codruta
authors.initials: C
authors.lastname: Soica
authors.affiliation: c Department of Pharmacodynamics and Biopharmacy , University of Szeged , Szeged , Hungary.
authors.forename: Istvan
authors.initials: I
authors.lastname: Zupko
authors.affiliation: c Department of Pharmacodynamics and Biopharmacy , University of Szeged , Szeged , Hungary.
authors.forename: Renata
authors.initials: R
authors.lastname: Minorics
authors.affiliation: b Faculty of Medicine , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Florina
authors.initials: F
authors.lastname: Bojin
authors.affiliation: d Department of Pharmaceutical Technology , University of Szeged , Szeged , Hungary.
authors.forename: Rita
authors.initials: R
authors.lastname: Ambrus
authors.affiliation: b Faculty of Medicine , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Delia
authors.initials: D
authors.lastname: Muntean
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Corina
authors.initials: C
authors.lastname: Danciu
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Iulia Andreea
authors.initials: IA
authors.lastname: Pinzaru
authors.affiliation: a Faculty of Pharmacy , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Cristina
authors.initials: C
authors.lastname: Dehelean
authors.affiliation: b Faculty of Medicine , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Virgil
authors.initials: V
authors.lastname: Paunescu
authors.affiliation: b Faculty of Medicine , University of Medicine and Pharmacy "Victor Babeş" , Timişoara , România.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Tanasie
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D045744:Cell Line, Tumor; D016503:Drug Delivery Systems; D006801:Humans; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures; D009828:Oleanolic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D010316:Particle Size; D011140:Polyurethanes / Q000008:administration & dosage*; D014315:Triterpenes / Q000008:administration & dosage / Q000494:pharmacology*; D000097245:Ursolic Acid
chemical_list: D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D009828:Oleanolic Acid; D011140:Polyurethanes; D014315:Triterpenes; D000097245:Ursolic Acid
keywords: Antitumor; breast cancer; minimal inhibitory concentration; oleanolic acid; ursolic acid