PMID- 17325185
OWN - NLM
STAT- MEDLINE
DCOM- 20070409
LR  - 20161124
IS  - 0146-0404 (Print)
IS  - 0146-0404 (Linking)
VI  - 48
IP  - 3
DP  - 2007 Mar
TI  - Caspase-8, -12, and -3 activation by 7-ketocholesterol in retinal neurosensory 
      cells.
PG  - 1362-7
AB  - PURPOSE: To determine the caspase pathways involved with 7-ketocholesterol 
      (7kCh)-induced apoptosis in rat R28 cells. METHODS: R28 cells were exposed to 
      7kCh with or without low-density lipoprotein (LDL) and z-VAD-fmk, a pan-caspase 
      inhibitor. Cell viability was measured by a trypan blue dye exclusion assay. 
      Caspase-3, -8, -9, and -12 activities were measured by fluorochrome caspase 
      assays. ARPE-19 cells were used as control for caspase-3 inhibition experiments. 
      RESULTS: R28 cultures showed decreased cell viability on 7kCh exposure compared 
      with controls (P < 0.001), and this was reversed with LDL and LDL + z-VAD-fmk (P 
      < 0.001). The 7kCh-treated R28 cultures had increased caspase-8 activity compared 
      with controls (P < 0.001). This activity was blocked partially with LDL (P < 
      0.01) or LDL + z-VAD-fmk (P < 0.001) but not with z-VAD-fmk alone. Caspase-12 
      activity was increased after 7kCh treatment compared with controls (P < 0.01), 
      and this activity was increased further with the addition of LDL. Caspase-3 
      activity in R28 cultures increased with 7kCh treatment compared with controls (P 
      < 0.001). In R28 cultures, the z-VAD-fmk treatment did not blocked 7kCh-induced 
      caspase-3 activity but did block activity in ARPE-19 cultures (P < 0.001). 
      Caspase-9 was not activated by 7kCh treatment. CONCLUSIONS: In R28 cells, 
      7kCh-induced apoptosis involves the caspase-3 along with the caspase-8 and 
      caspase-12 pathways. LDL partially blocked 7kCh-induced caspase-8 activity but 
      increased caspase-12 activities, suggesting that caspase-8 and caspase-12 
      pathways are independent of each other. The z-VAD-fmk inhibitor blocked caspase-3 
      activities in the homogeneous ARPE-19 cultures but not in the heterogeneous R28 
      cultures.
FAU - Neekhra, Aneesh
AU  - Neekhra A
AD  - Department of Ophthalmology, School of Medicine, University of California, 
      Irvine, California, USA. mkenney@uci.edu
FAU - Luthra, Saurabh
AU  - Luthra S
FAU - Chwa, Marilyn
AU  - Chwa M
FAU - Seigel, Gail
AU  - Seigel G
FAU - Gramajo, Ana L
AU  - Gramajo AL
FAU - Kuppermann, Baruch D
AU  - Kuppermann BD
FAU - Kenney, M Cristina
AU  - Kenney MC
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Invest Ophthalmol Vis Sci
JT  - Investigative ophthalmology & visual science
JID - 7703701
RN  - 0 (Amino Acid Chloromethyl Ketones)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Ketocholesterols)
RN  - 0 (Lipoproteins, LDL)
RN  - 0 (benzyloxycarbonyltyrosyl-valyl-alanyl-aspartic acid fluoromethyl ketone)
RN  - EC 3.4.22.- (Casp12 protein, rat)
RN  - EC 3.4.22.- (Casp3 protein, rat)
RN  - EC 3.4.22.- (Casp8 protein, rat)
RN  - EC 3.4.22.- (Caspase 12)
RN  - EC 3.4.22.- (Caspase 3)
RN  - EC 3.4.22.- (Caspase 8)
RN  - I2ZWO3LS3M (Trypan Blue)
RN  - O7676FE78M (7-ketocholesterol)
SB  - IM
MH  - Amino Acid Chloromethyl Ketones/pharmacology
MH  - Animals
MH  - Apoptosis/*drug effects
MH  - Caspase 12/*metabolism
MH  - Caspase 3/*metabolism
MH  - Caspase 8/*metabolism
MH  - Cell Line
MH  - Cell Survival
MH  - DNA Fragmentation
MH  - Enzyme Activation/drug effects
MH  - Enzyme Inhibitors/pharmacology
MH  - Humans
MH  - Ketocholesterols/*pharmacology
MH  - Lipoproteins, LDL/pharmacology
MH  - Neurons/*drug effects/enzymology
MH  - Rats
MH  - Retina/*cytology
MH  - Trypan Blue
EDAT- 2007/02/28 09:00
MHDA- 2007/04/10 09:00
CRDT- 2007/02/28 09:00
PHST- 2007/02/28 09:00 [pubmed]
PHST- 2007/04/10 09:00 [medline]
PHST- 2007/02/28 09:00 [entrez]
AID - 48/3/1362 [pii]
AID - 10.1167/iovs.06-0900 [doi]
PST - ppublish
SO  - Invest Ophthalmol Vis Sci. 2007 Mar;48(3):1362-7. doi: 10.1167/iovs.06-0900.