title: Continuous erythropoietin delivery by muscle-targeted gene transfer using in vivo electroporation.
abstract: It has been demonstrated that gene transfer by in vivo electroporation of mouse muscle increases the level of gene expression by more than 100-fold over simple plasmid DNA injection. We tested continuous rat erythropoietin (Epo) delivery by this method in normal rats, using plasmid DNA expressing rat Epo (pCAGGS-Epo) as the vector. A pair of electrodes was inserted into the thigh muscles of rat hind limbs and 100 microg of pCAGGS-Epo was injected between the electrodes. Eight 100-V, 50-msec electric pulses were delivered through the electrodes. Each rat was injected with a total of 400 microg of pCAGGS-Epo, which was delivered to the medial and lateral sides of each thigh. The presence of vector-derived Epo mRNA at the DNA injection site was confirmed by RT-PCR. The serum Epo levels peaked at 122.2 +/- 33.0 mU/ml on day 7 and gradually decreased to 35.9 +/- 18.2 mU/ml on day 32. The hematocrit levels increased continuously, from the preinjection level of 49.5 +/- 1.1 to 67.8 +/- 2.2% on day 32 (p < 0.001). In pCAGGS-Epo treated rats, endogenous Epo secretion was downregulated on day 32. In a control experiment, intramuscular injection of pCAGGS-Epo without subsequent electroporation did not significantly enhance the serum Epo levels. These results demonstrate that muscle-targeted pCAGGS-Epo transfer by in vivo electroporation is a useful procedure for the continuous delivery of Epo.
authors.affiliation: Department of Medicine II, Niigata University School of Medicine, Japan. hirokim@med.niigata-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Maruyama
authors.forename: M
authors.initials: M
authors.lastname: Sugawa
authors.forename: Y
authors.initials: Y
authors.lastname: Moriguchi
authors.forename: I
authors.initials: I
authors.lastname: Imazeki
authors.forename: Y
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: K
authors.initials: K
authors.lastname: Ataka
authors.forename: S
authors.initials: S
authors.lastname: Hasegawa
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: N
authors.initials: N
authors.lastname: Higuchi
authors.forename: J J
authors.initials: JJ
authors.lastname: Kazama
authors.forename: F
authors.initials: F
authors.lastname: Gejyo
authors.forename: J I
authors.initials: JI
authors.lastname: Miyazaki
mesh_terms: D000818:Animals; D018274:Electroporation; D004920:Erythropoiesis / Q000235:genetics; D004921:Erythropoietin / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D005293:Ferritins / Q000097:blood; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000008:administration & dosage; D006614:Hindlimb; D007273:Injections, Intramuscular; D007274:Injections, Intraperitoneal; D007501:Iron / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D018962:Phlebotomy; D010976:Platelet Count; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D004921:Erythropoietin; D005293:Ferritins; D007501:Iron