Induction of apoptosis by all-trans-retinoic acid and C2-ceramide treatment in rat stromal-vascular cultures.
Apoptosis of preadipocytes and adipocytes contributes to the balance of adipose tissue mass by reducing adipocyte number. To address this phenomenon, we treated cultured rat S-V cells with all-trans-retinoic acid (RA) (10 microM) or C2-ceramide (50 microM) during adipogenesis. Gel electrophoresis of DNA from treated cells cultured in serum-free medium showed that 10 microM RA or 50 microM ceramide induced a distinct laddering pattern of DNA fragments. Cellular caspase 3 activity, another marker of apoptosis, was increased by RA (10 microM) (P < 0.05), but not by 50 microm C2-ceramide. RT-PCR results showed that RA (10 microM) decreased the expression of Bcl-2 mRNA. These results suggest that fat cell loss by apoptosis can be regulated, in part, by RA (10 microM) which increases caspase 3 activity and decreases Bcl-2 expression in rat S-V cells. C2-ceramide apparently works through a different cellular mechanism to induce apoptosis.
Kim
H S
HS
Department of Animal and Dairy Science, USDA-ARS, Athens, Geogia, 30602, USA.
Hausman
D B
DB
Compton
M M
MM
Dean
R G
RG
Martin
R J
RJ
Hausman
G J
GJ
Hartzell
D L
DL
Baile
C A
CA
D017667:Adipocytes / Q000187:drug effects*; D000273:Adipose Tissue / Q000098:blood supply / Q000166:cytology / Q000187:drug effects; D000818:Animals; D017209:Apoptosis; D007264:Inguinal Canal; D007328:Insulin / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D013234:Stem Cells / Q000187:drug effects; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects*; D014212:Tretinoin / Q000494:pharmacology*; D014284:Triiodothyronine / Q000494:pharmacology
D007328:Insulin; C064769:N-acetylsphingosine; D014284:Triiodothyronine; D014212:Tretinoin; D013110:Sphingosine