PMID- 15277510
OWN - NLM
STAT- MEDLINE
DCOM- 20040831
LR  - 20161124
IS  - 0146-0404 (Print)
IS  - 0146-0404 (Linking)
VI  - 45
IP  - 8
DP  - 2004 Aug
TI  - Cytotoxicity of oxidized low-density lipoprotein in cultured RPE cells is 
      dependent on the formation of 7-ketocholesterol.
PG  - 2830-7
AB  - PURPOSE: To determine which components present in oxidized LDL are responsible 
      for the cytotoxicity associated with its internalization by culture ARPE19 cells. 
      METHODS: ARPE19 cells were grown in 24-well and 96-well plates. Cell viability 
      was measured by MTT and/or adenosine triphosphate (ATP) content. LDL was oxidized 
      with Cu(+2) and oxysterol content analyzed by a novel HPLC method. RESULTS: OxLDL 
      showed increased cytotoxicity with prolonged oxidation. Analysis of the oxLDL 
      showed a predominance of the 7-oxygenated products, 7 alpha-hydroxycholesterol (7 
      alpha HCh), 7 beta-hydroxycholesterol (7 beta HCh), and 7-ketocholesterol (7kCh). 
      Addition of these oxysterols to the ARPE19 cell in free form indicated that 7kCh 
      is the most cytotoxic of the oxysterols but at physiologically unrealistic 
      concentrations. Partitioning of individual oxysterols into nonoxidized LDL at 
      concentrations similar to those found in the oxLDL also indicated that 7kCh is 
      the most cytotoxic of the oxysterols. Transition metals are tightly bound by LDL 
      and play an important role in the oxidation of LDL, but do not seem to enhance 
      its cytotoxicity directly. CONCLUSIONS: Prolonged oxidation of LDL increases the 
      levels of 7kCh due to further oxidation of 7 alpha HCh and 7 beta HCh. The 
      formation of 7KCh seems to be responsible for most of the cytotoxicity associated 
      with oxLDL internalization in ARPE19 cells.
FAU - Rodriguez, Ignacio R
AU  - Rodriguez IR
AD  - Laboratory of Retinal Cell and Molecular Biology, Section on Mechanisms of 
      Retinal Diseases, National Eye Institute, National Institutes of Health, 
      Bethesda, Maryland 20892, USA. rodriguezi@nei.nih.gov
FAU - Alam, Shahabuddin
AU  - Alam S
FAU - Lee, Jung Wha
AU  - Lee JW
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Invest Ophthalmol Vis Sci
JT  - Investigative ophthalmology & visual science
JID - 7703701
RN  - 0 (Hydroxycholesterols)
RN  - 0 (Ketocholesterols)
RN  - 0 (Lipoproteins, LDL)
RN  - 0 (Tetrazolium Salts)
RN  - 0 (Thiazoles)
RN  - 0 (Transition Elements)
RN  - 0 (oxidized low density lipoprotein)
RN  - 566-26-7 (cholest-5-en-3 beta,7 alpha-diol)
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - EUY85H477I (thiazolyl blue)
RN  - O7676FE78M (7-ketocholesterol)
SB  - IM
MH  - Adenosine Triphosphate/metabolism
MH  - Cell Survival
MH  - Cells, Cultured
MH  - Chromatography, High Pressure Liquid
MH  - Drug Synergism
MH  - Humans
MH  - Hydroxycholesterols/metabolism
MH  - Ketocholesterols/*metabolism
MH  - Lipoproteins, LDL/*toxicity
MH  - Oxidation-Reduction
MH  - Pigment Epithelium of Eye/*drug effects/metabolism
MH  - Tetrazolium Salts/metabolism
MH  - Thiazoles/metabolism
MH  - Time Factors
MH  - Transition Elements/toxicity
EDAT- 2004/07/28 05:00
MHDA- 2004/09/01 05:00
CRDT- 2004/07/28 05:00
PHST- 2004/07/28 05:00 [pubmed]
PHST- 2004/09/01 05:00 [medline]
PHST- 2004/07/28 05:00 [entrez]
AID - 45/8/2830 [pii]
AID - 10.1167/iovs.04-0075 [doi]
PST - ppublish
SO  - Invest Ophthalmol Vis Sci. 2004 Aug;45(8):2830-7. doi: 10.1167/iovs.04-0075.