title: A Simple Method to Extract Whole Apolipoproteins for the Preparation of Discoidal Recombined High Density Lipoproteins as Bionic Nanocarriers for Drug Delivery.
abstract: OBJECTIVE
  To develop a simple method to extract the whole apolipoproteins (apo) including apoA-I in native high density lipoproteins (HDLs) and prepare discoidal Tanshinone IIA-loaded reconstituted HDL (TA-rHDLs) as a dual functional drug delivery system with plaque-site target and therapeutic promises in atherosclerotic lesions.
  
  
  METHODS
  A method based on isoelectric precipitation coupled with organic solvent precipitation was developed to isolate the whole apolipoproteins (apos). TA-rHDLs were prepared by incubating the resultant apos with liposomes and the incubation conditions were optimized using fluorescence quenching experiment. TA-rHDLs were characterized in terms of size, zeta potential, morphology, interaction between lipid and apos, safety, and bionic function.
  
  
  RESULTS
  The extraction results showed that the yield of the HDL apos was 82.4%, with 59% being apoA-I type, similar ratio of apoA-I in the native apos. TA-rHDL prepared were disc-like with an average diameter of 157.6 ± 4.8 nm, zeta potential of -20.90 ± 0.15 mV, and entrapment efficiency of (90.13 ± 1.4) %. The interaction between the lipids and apos was electrostatic and hydrophobic force and was associated with amino acid sequence. Haemolysis and cytotoxicity assays showed good biocompatibility of TA-rHDL. Sterol efflux assay from macrophages mediated by TA-rHDLs and structure remodeling behavior from discs to spheres proved that TA-rHDL could resemble the biological activity of native nascent HDL irrespective of the size.
  
  
  CONCLUSIONS
  The simple approach to isolate apos may provide a convenient and economical resource to support the development of rHDL as a potential targeting nanocarrier for lipophilic cardiovascular drugs.
authors.affiliation: Department of Pharmaceutics, China Pharmaceutical University, Nanjing, PR China.
authors.forename: Wenli
authors.initials: W
authors.lastname: Zhang
authors.forename: Ji
authors.initials: J
authors.lastname: Wang
authors.forename: Junting
authors.initials: J
authors.lastname: Jia
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Zimei
authors.initials: Z
authors.lastname: Wu
authors.forename: Jianping
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D001053:Apolipoproteins / Q000737:chemistry / Q000302:isolation & purification*; D011232:Chemical Precipitation; D004337:Drug Carriers / Q000737:chemistry*; D008075:Lipoproteins, HDL / Q000138:chemical synthesis* / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D011817:Rabbits
chemical_list: D001053:Apolipoproteins; D004337:Drug Carriers; D008075:Lipoproteins, HDL