Liposomal delivery of a 30-mer antisense oligodeoxynucleotide to inhibit proopiomelanocortin expression.
An oligodeoxynucleic sequence of 30 bases (30-mer ODN), complementary to a region of beta-endorphin mRNA, was synthesized to have an antisense effect with regard to the expression of this oligopeptide. Following the solid-phase synthesis of the oligodeoxynucleotide, the 30-mer ODN was encapsulated within liposomes to provide a higher resistance against DNases and an improved entrance into cells. The most suitable liposome formulation as a 30-mer ODN carrier consisted of small unilamellar vesicles (50 nm) with an encapsulation capacity of 4.76 microL/micromol. The liposomal formulations containing dipalmitoyl-DL-alpha-phosphatidyl-L-serine presented fusogenic properties, which are of great importance for the delivery of antisense compounds. The antisense activity of 30-mer ODN-loaded liposomes was evaluated by the determination of beta-endorphin levels in AtT-20 cells. The free 30-mer ODN did not provide any lowering of the beta-endorphin production, whereas the liposomally entrapped compound elicited a concentration-dependent inhibition. The inhibition was determined by a sequence-specific binding of the 30-mer ODN with the target mRNA.
Fresta
M
M
Dipartimento di Scienze Farmaceutiche, Facoltà di Farmacia, Università di Catania, Viale Andrea Doria 6, I-95125 Catania, Italy.
Chillemi
R
R
Spampinato
S
S
Sciuto
S
S
Puglisi
G
G
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000818:Animals; D002152:Calorimetry, Differential Scanning; D002460:Cell Line; D002784:Cholesterol / Q000737:chemistry; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D004337:Drug Carriers; D015870:Gene Expression / Q000187:drug effects*; D008081:Liposomes; D051379:Mice; D016376:Oligonucleotides, Antisense / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010718:Phosphatidylserines / Q000737:chemistry; D011333:Pro-Opiomelanocortin / Q000037:antagonists & inhibitors* / Q000737:chemistry; D012333:RNA, Messenger / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D001615:beta-Endorphin / Q000037:antagonists & inhibitors / Q000737:chemistry
D004337:Drug Carriers; D008081:Liposomes; D016376:Oligonucleotides, Antisense; D010718:Phosphatidylserines; D012333:RNA, Messenger; D015060:1,2-Dipalmitoylphosphatidylcholine; C038694:dipalmitoylphosphatidylserine; D001615:beta-Endorphin; D011333:Pro-Opiomelanocortin; D002784:Cholesterol; D004134:Dimyristoylphosphatidylcholine