Heat-induced reformulation of amphotericin B-deoxycholate favours drug uptake by the macrophage-like cell line J774.
OBJECTIVE
Heat treatment of deoxycholate-amphotericin B (AmB-DOC) leads to a therapeutically interesting supramolecular rearrangement (h-AmB-DOC); this reformulation improves the therapeutic index of AmB-DOC by reducing amphotericin B (AmB) toxicity in mammalian cell lines from 3- to 10-fold. Its activity in experimentally induced fungal infection in mice remains unchanged compared with AmB-DOC, whereas its activity is 2.5 times higher in Leishmania donovani-infected mice. This work investigates the in vitro mechanism that allows this improvement.


METHODS
In this study, we analysed the role of serum components on the interaction of h-AmB-DOC with two cultured cell lines: murine peritoneal macrophage cells (J774) and kidney epithelial cells (LLCPK1). The methods used were: spectrophotometry for AmB uptake; MTT assay for cell viability; and lactate dehydrogenase release for membrane damage.


RESULTS
In the presence of 10% fetal calf serum (FCS), the toxicity of AmB-DOC or h-AmB-DOC for both cell lines was null or weak. Interestingly, in J774 cells, the uptake of AmB in the form of h-AmB-DOC was much higher. In LLCPK1 cells, AmB uptake was more limited in both cases but remained higher with h-AmB-DOC. In the absence of FCS, no toxicity for either cell line was observed with h-AmB-DOC.


CONCLUSIONS
These findings confirm the importance of serum proteins in AmB biodistribution and suggest that, in vivo, the reduced toxicity and the improved antileishmanial activity of AmB-DOC after moderate heating may be the result of its increased uptake by macrophages.
Chéron
Monique
M
LPBC (UMR CNRS 7033), Université Pierre et Marie Curie, 4 place Jussieu, F-75252 Cedex 05, France.
Petit
Caroline
C
Bolard
Jacques
J
Gaboriau
François
F
D000465:Algorithms; D000666:Amphotericin B / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D000818:Animals; D000935:Antifungal Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D003840:Deoxycholic Acid / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D004338:Drug Combinations; D006358:Hot Temperature; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D018374:LLC-PK1 Cells; D008077:Lipoproteins, LDL / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D013552:Swine; D013778:Tetrazolium Salts; D013844:Thiazoles
D000935:Antifungal Agents; D004338:Drug Combinations; D008077:Lipoproteins, LDL; D013778:Tetrazolium Salts; D013844:Thiazoles; D003840:Deoxycholic Acid; D000666:Amphotericin B; C059765:amphotericin B, deoxycholate drug combination; D007770:L-Lactate Dehydrogenase; C022616:thiazolyl blue