title: Improvement of therapeutic efficacy of PLGA nanoformulation of siRNA targeting anti-apoptotic Bcl-2 through chitosan coating.
abstract: Potential use of siRNA as therapeutic agent has elicited a great deal of interest. However, insufficient cellular uptake and poor stability limited its application in therapeutics. In our earlier study, we prepared PLGA nanoparticles for effective delivery of siRNA targeting Bcl-2 gene to block its expression. Purpose of the present study was to improve effectiveness of PLGA nanoformulation of siRNA targeting anti-apoptotic Bcl-2 gene through chitosan coating. We prepared chitosan coated PLGA nanoparticles by using the double emulsion solvent diffusion (DESE) method. Characterization of prepared chitosan coated nanoformulation was done followed by cytotoxicity studies, expression studies and in vivo studies. Particle size of chitosan coated nanoparticles was found to be increased compared to PLGA nanoparticles from 244 to 319 nm. Surface charge of chitosan coated nanoparticles was found to be positive facilitating transfection of nanoformulation into cells. In vitro studies indicated increased transfection of nanoparticles resulting in effective silencing of Bcl-2. Marked apoptotic lesions were observed in nuclear staining studies. On comparison of the results from the present study with those of previous study, it was found that the extent of silencing of Bcl-2 gene by PLGA nanoformulation has improved significantly through chitosan coating. In vivo studies showed significant tumor regression in animals treated with chitosan coated PLGA nanoformulation of siRNA.
authors.affiliation: Department of Pharmaceutical Biotechnology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal 576 104, Karnataka, India.
authors.forename: Hitesh Vitthalbhai
authors.initials: HV
authors.lastname: Jagani
authors.forename: Venkata Rao
authors.initials: VR
authors.lastname: Josyula
authors.forename: Vasanth Raj
authors.initials: VR
authors.lastname: Palanimuthu
authors.forename: Raghu Chandrashekar
authors.initials: RC
authors.lastname: Hariharapura
authors.forename: Sagar Shantimal
authors.initials: SS
authors.lastname: Gang
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000008:administration & dosage* / Q000737:chemistry; D005260:Female; D020868:Gene Silencing; D019254:Genes, bcl-2; D006801:Humans; D019344:Lactic Acid / Q000008:administration & dosage* / Q000737:chemistry; D008297:Male; D051379:Mice; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D010316:Particle Size; D011100:Polyglycolic Acid / Q000008:administration & dosage* / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics* / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000737:chemistry; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D048271:Chitosan