The experiment in the mechanisms of microbubble-mediated GFP gene enhancement in skeletal muscle in C57B10/mdx mice

Abstract

Objective To investigate the role of sonoporation and the deblic of microbubbles with perfluoropropane gas and albumin in the mechanisms of microbubble-mediated gene enhancement by experimenting in skeletal muscle in C57B10/mdx mice. Methods Plasmid DNA (10 μg) encoding green fluorescent protein (GFP) was mixed with Optison or SonoVue dissolved in saline and injected into the tibialis anterior (TA) muscle of /C57B10/mdx mice with and without adjunct ultrasound. The efficiencies of GFP transgene expression were determined under different experimental conditions. C57B10 mice as normal control:①C57B10 mice + saline (4 left TAs);②C57B10 mice + saline + ultrasound (4 right TAs) ;③C57B10 mice + Optison(4 left TAs);④C57B10 mice+ Optison + ultrasound(4 right TAs);⑤ C57B10 mice + SonoVue(4 left TAs) ;⑥C57B10 mice + SonoVue + ultrasound(4 right TAs). Mdx mice groups:① mdx mice + saline(4 left TAs) ;② mdx mice + saline + ultrasound(4 right TAs);③ mdx mice + Optison (4 left TAs) ; ④ mdx mice + Optison + ultrasound (4 right TAs); ⑤mdx mice + SonoVue(4 left TAs) ;⑥mdx mice + SonoVue + ultrasound(4 right TAs). Mice were sacrificed 1 week after plasmid DNA injection. Fibres with fluorescence green signals were determined as GFP-positive fibres by fluorescence microscopy. Readout was performed on the section with the maximum number of transfected fibers. Results C57B10 mice: ?Optison without ultrasound had significantly increased gene expression compared with negative control ( P <0. 01). SonoVue without ultrasound did not enhance gene expression. ?Optison with ultrasound had significantly increased gene expression compared with negative control (P < 0.01). ?SonoVue with ultrasound had significantly increased gene expression compared with negative control ( P<0. 01).Mdx mice:? Compared with C57B10 mice, GFP alone demonstrated significant GFP expression in mdx mice ( P <0. 01) , Optison demonstrated significant GFP expression in mdx mice ( P <0.01), and SonoVue demonstrated significant GFP expression in mdx mice ( P <0. 01). ?Microbubble groups (Optison and SonoVue) had significantly increased gene expression compared with negative control (P <0. 01). Conclusions In the mechanisms of microbubble-mediated gene enhancement, sonoporation is the key step. The deblic of microbubbles with perfluoropropane gas and albumin is the main constituent in the mechanisms of Optison-mediated gene enhancement. fibers.Results C5781 0 mice:①Optison without ultrasound had significantly increased gene expressioncompared with negative control(P<0.01).SonoVue without ultrasound did not enhance gene expression.②Optison with ultrasound had significantly increased gene expression compared with negative control(P<0.01).③SonoVue with ultrasound had significantly increased gene expression compared with negativecontr01(P<O.01).Mdx mice:①Compared with C57810 mice,GFP alone demonstrated significant GFPexpression in mdx mice(P<0.01),0prison demonstrated significant GFP expression in mdx mice(P<0.01),and SonoVue demonstrated significant GFP expression in mdx mice(P<0.01).②Microbubblegroups(0ptison and SonoVue)had significantly increased gene expression compared with negative control(P<0.01).Conclusions In the mechanisms of microbubble-mediated gene enhancement,sonoporation isthe key step.The deblic of microbubbles with perfluoropropane gas and albumin is the main constituent inthe mechanisms of Optison-mediated gene enhancement. Key words: Ultrasonography; Microbubbles; Transfection