PMID- 11785781
OWN - NLM
STAT- MEDLINE
DCOM- 20020627
LR  - 20191105
IS  - 1098-8823 (Print)
IS  - 1098-8823 (Linking)
VI  - 66
IP  - 4
DP  - 2001 Dec
TI  - Oxidized low density lipoprotein inhibits prostacyclin generation by rat aorta in 
      vitro: a key role of lysolecithin.
PG  - 283-304
AB  - The objective of this study was to examine the effect of oxLDL on prostacyclin 
      (PGI2) generation by rat aortic segments and to see whether the lipid fraction of 
      oxLDL or its components are responsible for that effect. We also tested if 
      antioxidants have any protective role. LDL oxidized by copper was characterized 
      by higher TBARS, conjugated diene, lysophosphatidylcholine (lyso PC), oxysterols 
      and less polyunsaturated fatty acids (PUFA) than nLDL. Preincubation of aortas 
      with oxLDL caused a significant inhibition of PGI2 generation compared to aortas 
      preincubated with nLDL or buffer only. The percent inhibition was dependent on 
      the concentration of oxLDL. Most of the inhibitory effect of oxLDL resided in its 
      lipid moiety while the lipid fraction of nLDL, as well as native LDL had no 
      effect. Preincubation of aortas with 10 microg/ml of 7-ketocholesterol the major 
      oxysterol in oxLDL reduced the amount of PGI2 generated by aorta at all times 
      tested; however that decrease did not reach a significant level. Aortas 
      preincubated with 10 microg/ml of lyso PC showed a 21-36% inhibition of PGI2 
      generation which was comparable to the inhibition produced by preincubating the 
      aortas with 50 microg protein/ml of oxLDL (containing about 7.5 microg lyso PC). 
      This indicated that most of the inhibitory effect of oxLDL was due to its lyso 
      PC. The small molecular weight fraction (< 10 kDa) with a high level of TBARS 
      (TBARS solution) also significantly decreased the PGI2 generation by aorta. 
      Addition of superoxide dismutase (SOD) + catalase or vitamin E simultaneously 
      with oxLDL or TBARS solution in the preincubation medium did not reverse their 
      inhibitory effects. This indicated that oxygen free radicals are not a 
      contributing factor to the inhibitory effect of oxLDL but lyso PC and the lipid 
      peroxides and probably other components already present within oxLDL are the 
      important inhibitors.
FAU - Mahfouz, M
AU  - Mahfouz M
AD  - University of Illinois, Burnsides Research Laboratory, Urbana 61801, USA.
FAU - Kummerow, F
AU  - Kummerow F
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Prostaglandins Other Lipid Mediat
JT  - Prostaglandins & other lipid mediators
JID - 9808648
RN  - 0 (Antioxidants)
RN  - 0 (Ketocholesterols)
RN  - 0 (Lipoproteins, LDL)
RN  - 0 (Lysophosphatidylcholines)
RN  - 0 (Solutions)
RN  - 0 (Thiobarbituric Acid Reactive Substances)
RN  - 1406-18-4 (Vitamin E)
RN  - DCR9Z582X0 (Epoprostenol)
RN  - EC 1.11.1.6 (Catalase)
RN  - EC 1.15.1.1 (Superoxide Dismutase)
RN  - O7676FE78M (7-ketocholesterol)
SB  - IM
MH  - Animals
MH  - Antioxidants/metabolism
MH  - Aorta/drug effects/*metabolism
MH  - Catalase/metabolism
MH  - Epoprostenol/*metabolism
MH  - Humans
MH  - In Vitro Techniques
MH  - Ketocholesterols/pharmacology
MH  - Lipoproteins, LDL/chemistry/metabolism/*pharmacology
MH  - Lysophosphatidylcholines/*pharmacology
MH  - Oxidation-Reduction
MH  - Rats
MH  - Solutions
MH  - Superoxide Dismutase/drug effects/metabolism
MH  - Thiobarbituric Acid Reactive Substances/pharmacology
MH  - Vitamin E/pharmacology
EDAT- 2002/01/12 10:00
MHDA- 2002/06/28 10:01
CRDT- 2002/01/12 10:00
PHST- 2002/01/12 10:00 [pubmed]
PHST- 2002/06/28 10:01 [medline]
PHST- 2002/01/12 10:00 [entrez]
AID - S0090-6980(01)00166-6 [pii]
AID - 10.1016/s0090-6980(01)00166-6 [doi]
PST - ppublish
SO  - Prostaglandins Other Lipid Mediat. 2001 Dec;66(4):283-304. doi: 
      10.1016/s0090-6980(01)00166-6.