Tumor necrosis factor-related apoptosis inducing ligand expression and activity in hen granulosa cells.
Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) represents one of several cytokine members of the tumor necrosis factor superfamily reported to initiate apoptosis in a wide range of transformed, but not most normal, cell types. The present studies were conducted to evaluate the potential for TRAIL to promote apoptotic cell death in differentiated granulosa cells collected from hen preovulatory follicles. While mRNA encoding critical components (including TRAIL) required for a functional extrinsic cell death pathway are expressed in granulosa cells, TRAIL treatment by itself fails to induce either caspase-3 activity or a decrease in cell viability. On the other hand, preculture of cells with the conventional chemotherapeutic, cisplatin, or the 20S proteosome inhibitor, Z-LLF-CHO, sensitizes granulosa cells to TRAIL as evidenced by enhanced caspase-3 activity after 4 h of culture and loss of cell viability after 24 h when compared with either cisplatin or Z-LLF-CHO treatment alone. Moreover, the sensitizing effect of Z-LLF-CHO on TRAIL-induced loss of cell viability is prevented by the selective caspase-8 inhibitor, Z-IETD-FMK. Interestingly, TRAIL mRNA expression is elevated both in prehierarchal follicles undergoing spontaneous atresia and in prehierarchal follicles induced to undergo atresia for 6 h in vitro. In summary, the data demonstrate the presence of a functional TRAIL signaling pathway in hen granulosa cells, and are consistent with the possibility that TRAIL signaling may directly or indirectly participate in the process of follicle atresia in vivo.
Johnson
A L
AL
Department of Biological Sciences and Walther Cancer Institute, The University of Notre Dame, PO Box 369, Notre Dame, Indiana 46556, USA. johnson.128@nd.edu
Ratajczak
Christine
C
Haugen
Morgan J
MJ
Liu
Han-Ken
HK
Woods
Dori C
DC
D000818:Animals; D017209:Apoptosis / Q000235:genetics; D015152:Blotting, Northern; D053148:Caspase 3 / Q000032:analysis / Q000378:metabolism; D002452:Cell Count; D002478:Cells, Cultured; D002645:Chickens / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005496:Follicular Atresia / Q000378:metabolism*; D015870:Gene Expression; D006107:Granulosa Cells / Q000737:chemistry* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000032:analysis* / Q000235:genetics / Q000378:metabolism
D017931:DNA Primers; D053221:TNF-Related Apoptosis-Inducing Ligand; D053148:Caspase 3