The role of cFLIP as anti-apoptotic protein in the bovine corpus luteum

Abstract EN

Apoptosis, programmed cell death, is a key mechanism in luteal regression.

Improving our understanding of pro- and anti-apoptotic factors during luteolysis can advance our knowledge and may lead to a new strategy in manipulating luteolysis.

This study aimed to elucidate the role of cellular Fas like interleukin converting enzyme (FLICE) inhibitory protein {cFLIP} an anti-apoptotic protein, in the bovine corpus luteum function.

Corpora lutea were collected at different stages throughout the estrous cycle for immunolocalization of cFLIP.

Additionally, cultured mid luteal cells were treated with IFNγ/TNFα (tumor necrosis factor alpha/ interferon gamma) to induce apoptosis and examine cFLIP expression.

Immunostaining was found predominantly in the cytoplasm of luteal and non-luteal cells, including endothelial and immune cells.

The density of cFLIP immunostaining was high during the early, developing and mid luteal stages and then decreased significantly (P<0.05) at the late and regressed luteal stages.

Macrophage like cells were the only type of cells immunostained in the regressing CL.

However, cultured mid luteal cells showed higher percentage of cFLIP positive cells with lower percentage of TUNEL (terminal deoxynucleotidyl transferase- mediated dUTP nick-end labelling) positive cells compared with treated luteal cells with cytokines (P<0.01).

The above results suggested regulation of cFLIP during structural luteal regression and cFLIP plays a crucial role in the bovine CL.