Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
Southwest National Primate Research Center, San Antonio, TX, USA.
IUBMB Life. 2017 Sep;69(9):745-755. doi: 10.1002/iub.1658. Epub 2017 Jul 31.
Ultrasound-targeted microbubble destruction (UTMD) is a novel means of tissue-specific gene delivery. This approach systemically infuses transgenes precoupled to gas-filled lipid microbubbles that are burst within the microvasculature of target tissues via an ultrasound signal resulting in release of DNA and transfection of neighboring cells within the tissue. Previous work has shown that adenovirus containing cDNA of UCP-1, injected into the epididymal fat pads in mice, induced localized fat depletion, improving glucose tolerance, and decreasing food intake in obese diabetic mice. Our group recently demonstrated that gene therapy by UTMD achieved beta cell regeneration in streptozotocin (STZ)-treated mice and baboons. We hypothesized that gene therapy with BMP7/PRDM16/PPARGC1A in skeletal muscle (SKM) of obese Zucker diabetic fatty (fa/fa) rats using UTMD technology would produce a brown adipose tissue (BAT) phenotype with UCP-1 overexpression. This study was designed as a proof of concept (POC) project. Obese Zucker rats were administered plasmid cDNA contructs encoding a gene cocktail with BMP7/PRDM16/PPARGC1A incorporated within microbubbles and intravenously delivered into their left thigh. Controls received UTMD with plasmids driving a DsRed reporter gene. An ultrasound transducer was directed to the thigh to disrupt the microbubbles within the microcirculation. Blood samples were drawn at baseline, and after treatment to measure glucose, insulin, and free fatty acids levels. SKM was harvested for immunohistochemistry (IHC). Our IHC results showed a reliable pattern of effective UTMD-based gene delivery in enhancing SKM overexpression of the UCP-1 gene. This clearly indicates that our plasmid DNA construct encoding the gene combination of PRDM16, PPARGC1A, and BMP7 reprogrammed adult SKM tissue into brown adipose cells in vivo. Our pilot established POC showing that the administration of the gene cocktail to SKM in this rat model of genetic obesity using UTMD gene therapy, engineered a BAT phenotype with UCP-1 over-expression. © 2017 IUBMB Life, 69(9):745-755, 2017.
超声靶向微泡破坏（UTMD）是一种组织特异性基因传递的新方法。该方法系统地将与充满气体的脂质微泡预偶联的转基因注入目标组织的微血管中，通过超声信号使微泡破裂，导致 DNA 释放并转染组织内的邻近细胞。以前的工作表明，将含有 UCP-1 cDNA 的腺病毒注入小鼠的附睾脂肪垫中，可诱导局部脂肪消耗，改善肥胖糖尿病小鼠的葡萄糖耐量，并减少食物摄入。我们的研究小组最近证明，UTMD 基因治疗可实现链脲佐菌素（STZ）处理的小鼠和狒狒的胰岛细胞再生。我们假设，使用 UTMD 技术，在肥胖的 Zucker 糖尿病肥胖（fa/fa）大鼠的骨骼肌（SKM）中进行 BMP7/PRDM16/PPARGC1A 基因治疗，将产生具有 UCP-1 过表达的棕色脂肪组织（BAT）表型。这项研究旨在作为概念验证（POC）项目。肥胖的 Zucker 大鼠给予编码基因鸡尾酒的质粒 cDNA 构建体，该基因鸡尾酒将 BMP7/PRDM16/PPARGC1A 纳入微泡中，并静脉内递送至其左大腿。对照组接受带有驱动 DsRed 报告基因的 UTMD。将超声换能器引导至大腿，以破坏微泡在微循环中的破裂。在基线和治疗后抽血以测量血糖、胰岛素和游离脂肪酸水平。采集 SKM 进行免疫组织化学（IHC）分析。我们的 IHC 结果显示了一种可靠的基于 UTMD 的基因传递模式，可有效增强 SKM 中 UCP-1 基因的过表达。这清楚地表明，我们编码 PRDM16、PPARGC1A 和 BMP7 基因组合的质粒 DNA 构建体在体内将成年 SKM 组织重新编程为棕色脂肪细胞。我们的初步研究结果表明，在这种遗传性肥胖大鼠模型中，通过 UTMD 基因治疗将基因鸡尾酒施用于 SKM，可在体内产生具有 UCP-1 过表达的 BAT 表型。2017 IUBMB 生命，69（9）：745-755，2017。
