Expression and localization of cFLIP anti-apoptotic protein in the porcine corpus luteum and corpora albicans during the estrous cycle and pregnancy

Abstract

ABSTRACT. We determined expression and localization of the antiapoptotic cellular FLICE inhibitory protein (cFLIP) in the porcine corpora lutea (CL) and corpus albicans (CA) during estrous and pregnancy. The CL and CA were collected at different stages of estrous to determine cFLIP immunolocalization, and mRNA and protein expression. The mRNA expression of the short cFLIP isoform (cFLIP S ) was higher at the early and mid CL stages, and lower by the late CL stage (P < 0.01); mRNA expression of the long cFLIP isoform (cFLIP L ) was higher at the mid CL stage, and lower at the early and late CL stages (P < 0.01). Levels of cFLIP S and cFLIP L were steady and high during the early and mid CL stages, and had significantly decreased (P < 0.01) by the late stage. The cFLIP protein was highly expressed in the early and mid CL stages of estrous, but weakly expressed in the late stage. Expression of cFLIP S showed no significant difference between preovulatory corpus albicans (CA1) and corpus (2015) albicans (CA2) coexistent with the CL from the previous estrus, but cFLIP L mRNA expression was higher during CA1 than CA2. The expression of cFLIP S showed no significant difference between CA1 and CA2, but cFLIP L was not detected. The cFLIP protein was weakly expressed in the CA. Expression of cFLIP S and cFLIP L mRNA and proteins was observed in the CL, and the cFLIP protein was highly expressed during pregnancy. We propose that cFLIP S/L acts as a survival factor, and performs an anti-apoptotic function in the porcine CL.

Expression and localization of cellular FLICE-like inhibitory protein (cFLIP), an anti-apoptotic factor, in corpora lutea during the estrous cycle and pregnancy in Thai swamp buffalo <i>(Bubalus bubalis)</i>

“…The mRNA expression levels of cFLIP S and cFLIP L were high during the pregnancy period, but there was no significant difference between cFLIP L during the estrous cycle and pregnancy. A recent study reported that high levels of cFLIP mRNA and protein were shown during the mid stages of the estrous cycle and pregnancy in porcine CLs [15]. The present study found significantly high levels of cFLIP mRNA and protein in CLs of Thai swamp buffalos during the early stage of the estrous cycle and during pregnancy (P < 0.05).…”

“…Apoptosis is a form of physiological cell death and has been demonstrated in luteal cells during luteolysis in cows [2][3][4], humans [5], sows [6], and rats [7]. It is well established that apoptosis is the dominant mechanism regulating apoptosis of granulosa [8][9][10] and luteal cells [2,[11][12][13][14][15]. Studies on apoptosis signal transduction have focused on cell death ligand-and receptor-dependent intracellular signaling.…”

Expression Pattern of Apoptotic Genes During Different Stages of Corpus Luteum Development in Egyptian Buffaloes

“…When luteolysis occurs, luteal cells exhibit a sort of spontaneous cell death called apoptosis (Sugino and okuda, 2007). It is well known that apoptosis is the major mechanism controlling luteolysis in luteal cells ( Jin et al, 2015).…”