Interaction of Lipoplex with Albumin Enhances Gene Expression in Hepatitis Mice

Understanding the in vivo fate of lipoplex, which is composed of cationic liposomes and DNA, is an important issue toward gene therapy. In disease conditions, the fate of lipoplex might change compared with the normal condition. Here, we examined the contribution of interaction with serum components to in vivo transfection using lipoplex in hepatitis mice. Prior to administration, lipoplex was incubated with serum or albumin. In the liver, the interaction with albumin enhanced gene expression in hepatitis mice, while in the lung, the interaction with serum or albumin enhanced it. In normal mice, the interaction with albumin did not enhance hepatic and pulmonary gene expression. Furthermore, hepatic and pulmonary gene expression levels of albumin-interacted lipoplex were correlated with serum transaminases in hepatitis mice. The albumin interaction increased the hepatic accumulation of lipoplex and serum tumor necrosis factor-α level. We suggest that the interaction with albumin enhanced the inflammation level after the administration of lipoplex in hepatitis mice. Consequently, the enhancement of the inflammation level might enhance the gene expression level. Information obtained in the current study will be valuable toward future clinical application of the lipoplex.

PL-020 Establishment of skeletal muscle-specific PGC-1α overexpression model via in vivo local transfection

Objective To establish a skeletal muscle-specific PGC-1α overexpression mouse model via in vivo local transfection. Methods For the PGC-1α in vivo transfection study, the Male FVB/N mice were randomly divided into 2 groups: subject to green fluorescent protein (GFP) transfection (Con-GFP), and subject to PGC-1α in vivo transfection (Con-PGC-1α). Plasmid DNA solution (2.5 mg/ml GFP or 2.7 mg/ml Flag-PGC-1α) were injected into the proximal (6 ml) and distal (6 ml) ends of the muscle belly. Following the injections, electric pulses were applied through 2 stainless steel pin electrodes laid on top of the proximal and distal myotendinous junctions. Then skeletal muscle and myocardium were isolated, and PGC-1α, mtTFA, NF-κB, MnSOD, FNDC5 protein expression were measured with Western blot. Results n skeletal muscle, compared with con-GFP group, the expression of PGC-1α (+125%, p<0.01), mtTFA (+210%, p<0.01), and FNDC5 (+47%, p<0.05) were significantly increased in con-PGC-1α group. However, NF-κB and MnSOD protein level had no change in con-PGC-1α group. In myocardium, compared with con-GFP group, the expression of mtTFA (+130%, p<0.01) and FNDC5 (+55%, p<0.05) were significantly increased in con-PGC-1α group. Conclusions Skeletal muscle-specific PGC-1α overexpression model via in vivo local transfection was established, which was supported by elevated expression of PGC-1α and its downstream FNDC5 and mtTFA. Furthermore, skeletal muscle-specific PGC-1α overexpression induced increase in myocardial mitochondrial biogenesis, while relative mechanism remains to be determined.