title: Enhanced delivery of monomethoxypoly(ethylene glycol)-poly(lactic-co-glycolic acid)-poly l-lysine nanoparticles loading platelet-derived growth factor BB small interfering RNA by ultrasound and/or microbubbles to rat retinal pigment epithelium cells.
abstract: BACKGROUND
  A novel small interfering RNA (siRNA) delivery method based on the combined use of nanoparticles (NPs) with ultrasound (US) and/or microbubbles (MBs) was introduced in the present study. We investigated the efficacy and safety of US and/or MBs-enhanced delivery of monomethoxypoly(ethylene glycol)-poly(lactic-co-glycolic acid)-poly l-lysine (mPEG-PLGA-PLL) NPs loading platelet-derived growth factor BB (PDGF-BB) siRNA to rat retinal pigment epithelium (RPE)-J cells.
  
  
  METHODS
  The effect of US and/or MBs on the delivery of NPs containing Cy3-labeled siRNA was evaluated by fluorescence microscopy and flow cytometry. Potential toxicity of NPs and cell viability under different conditions of US and/or MBs were assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.
  
  
  RESULTS
  The results obtained showed that low intensity US or 15-20% MBs could increase the delivery efficiency of a lower concentration of mPEG-PLGA-PLL NPs loading siRNA to RPE-J cells, whereas the combination of US with MBs under the optimal conditions for the enhancement of NPs delivery did not further increase the cellular uptake of NPs compared to either US or MBs alone (p = 0.072 and p = 0.488, respectively). Under the optimal condition for US-enhanced NPs delivery, the enhanced PDGF-BB gene silencing with a combination of US and NPs encapsulating siRNA resulted in a significant decrease of mRNA and protein expression levels compared to NPs alone.
  
  
  CONCLUSIONS
  US and/or MBs could be used safely to enhance the delivery of NPs loading siRNA to rat RPE-J cells. A combination of the chemical (mPEG-PLGA-PLL NPs loading siRNA) and physical (US) approaches could more effectively downregulate the mRNA and protein expression of PDGF-BB.
authors.affiliation: Department of Ultrasound, Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University School of Medicine, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Du
authors.forename: Qiu Sheng
authors.initials: QS
authors.lastname: Shi
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.forename: Pei Feng
authors.initials: PF
authors.lastname: Liu
authors.forename: Ming Jie
authors.initials: MJ
authors.lastname: Zhu
authors.forename: Lian Fang
authors.initials: LF
authors.lastname: Du
authors.forename: You Rong
authors.initials: YR
authors.lastname: Duan
mesh_terms: D000818:Animals; D000077214:Becaplermin; D018929:Cell Culture Techniques / Q000379:methods; D017931:DNA Primers / Q000235:genetics; D016503:Drug Delivery Systems / Q000379:methods*; D004847:Epithelial Cells / Q000378:metabolism*; D008239:Lysine / Q000008:administration & dosage / Q000378:metabolism; D045423:Microbubbles / Q000627:therapeutic use*; D053758:Nanoparticles / Q000008:administration & dosage*; D010982:Platelet-Derived Growth Factor / Q000235:genetics*; D011091:Polyesters / Q000008:administration & dosage / Q000378:metabolism; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000378:metabolism; D020574:Proto-Oncogene Proteins c-sis; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D051381:Rats; D055213:Retinal Pigment Epithelium / Q000166:cytology / Q000378:metabolism; D014465:Ultrasonics
chemical_list: D017931:DNA Primers; D010982:Platelet-Derived Growth Factor; D011091:Polyesters; D020574:Proto-Oncogene Proteins c-sis; D034741:RNA, Small Interfering; C466993:poly(lactic-co-glycolic acid)-grafted-poly(L-lysine); D000077214:Becaplermin; D011092:Polyethylene Glycols; C028210:monomethoxypolyethylene glycol; D008239:Lysine