title: Enhanced transfection by antioxidative polymeric gene carrier that reduces polyplex-mediated cellular oxidative stress.
abstract: OBJECTIVE
  To test the hypothesis in which polyplex-induced oxidative stress may affect overall transfection efficiency, an antioxidative transfection system minimizing cellular oxidative stress was designed for enhanced transfection.
  
  
  METHODS
  An amphiphilic copolymer (PEI-PLGA) was synthesized and used as a micelle-type gene carrier containing hydrophobic antioxidant, α-tocopherol. Cellular oxidative stress and the change of mitochondrial membrane potential after transfection was measured by using a fluorescent probe (H₂DCFDA) and lipophilic cationic probe (JC-1), respectively. Transfection efficiency was determined by measuring a reporter gene (luciferase) expression level.
  
  
  RESULTS
  The initial transfection study with conventional PEI/plasmid DNA polyplex showed significant generation of reactive oxygen species (ROS). The PEI-PLGA copolymer successfully carried out the simultaneous delivery of α-tocopherol and plasmid DNA (PEI-PLGA/Toco/pDNA polyplex) into cells, resulting in a significant reduction in cellular ROS generation after transfection and helped to maintain the mitochondrial membrane potential (ΔΨ). In addition, the transfection efficiency was dramatically increased using the antioxidative transfection system.
  
  
  CONCLUSIONS
  This work showed that oxidative stress would be one of the important factors that should be considered in designing non-viral gene carriers and suggested a possible way to reduce the carrier-mediated oxidative stress, which consequently leads to enhanced transfection.
authors.affiliation: School of Pharmacy, Sungkyunkwan University, Suwon, 440-746, Republic of Korea.
authors.forename: Min Sang
authors.initials: MS
authors.lastname: Lee
authors.forename: Nak Won
authors.initials: NW
authors.lastname: Kim
authors.forename: Kyuri
authors.initials: K
authors.lastname: Lee
authors.forename: Hongtae
authors.initials: H
authors.lastname: Kim
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Jeong
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D004247:DNA / Q000235:genetics; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics*; D045325:HCT116 Cells; D056945:Hep G2 Cells; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007097:Imines / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry; D008156:Luciferases / Q000737:chemistry / Q000235:genetics; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000235:genetics; D008823:Micelles; D018384:Oxidative Stress / Q000187:drug effects* / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D011095:Polyethylenes / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014162:Transfection / Q000379:methods; D024502:alpha-Tocopherol / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D007097:Imines; D008823:Micelles; D011095:Polyethylenes; D011108:Polymers; D017382:Reactive Oxygen Species; C505405:poly(ethylene imine); D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D004247:DNA; D008156:Luciferases; D024502:alpha-Tocopherol
references.citation: Science. 1997 Mar 14;275(5306):1649-52
references.pmid: 9054359
references.citation: Mol Pharm. 2011 Oct 3;8(5):1709-19
references.pmid: 21699201
references.citation: Mol Pharm. 2011 Jun 6;8(3):976-81
references.pmid: 21446747
references.citation: Adv Drug Deliv Rev. 2006 Jul 7;58(4):467-86
references.pmid: 16781003
references.citation: Biochem J. 2009 Jan 1;417(1):1-13
references.pmid: 19061483
references.citation: Science. 2005 May 6;308(5723):804-6
references.pmid: 15879201
references.citation: Annu Rev Pharmacol Toxicol. 2007;47:143-83
references.pmid: 17029566
references.citation: Mol Ther. 2005 Jun;11(6):990-5
references.pmid: 15922971
references.citation: Toxicol Appl Pharmacol. 2010 Jan 15;242(2):146-54
references.pmid: 19822165
references.citation: Environ Health Perspect. 2003 Apr;111(4):455-60
references.pmid: 12676598
references.citation: J Nutr Biochem. 2010 Dec;21(12):1222-31
references.pmid: 20153624
references.citation: Biomaterials. 2007 Jul;28(19):2946-58
references.pmid: 17379299
references.citation: Science. 2006 Feb 3;311(5761):622-7
references.pmid: 16456071
references.citation: Nano Lett. 2006 Aug;6(8):1794-807
references.pmid: 16895376
references.citation: Proc Natl Acad Sci U S A. 1995 Aug 1;92(16):7297-301
references.pmid: 7638184
references.citation: Biochem J. 1999 Sep 15;342 Pt 3:481-96
references.pmid: 10477257
references.citation: Toxicol Lett. 2008 Aug 28;180(3):222-9
references.pmid: 18662754
references.citation: J Gene Med. 2004 Oct;6(10):1102-11
references.pmid: 15386739
references.citation: Annu Rev Nutr. 1990;10:357-82
references.pmid: 2200468
references.citation: Bioconjug Chem. 2002 Sep-Oct;13(5):952-7
references.pmid: 12236776
references.citation: Proc Natl Acad Sci U S A. 1991 May 1;88(9):3671-5
references.pmid: 2023917
references.citation: Biomaterials. 2003 Mar;24(7):1121-31
references.pmid: 12527253
references.citation: Cell. 2005 Feb 25;120(4):483-95
references.pmid: 15734681
references.citation: Biomaterials. 2009 Aug;30(23-24):3891-914
references.pmid: 19427031
references.citation: Biochim Biophys Acta. 2010 Jun-Jul;1797(6-7):1203-9
references.pmid: 20381448
references.citation: Biomaterials. 2011 Jul;32(20):4647-58
references.pmid: 21477858