Dynamic expression of caspase-2, -3, -8, and -9 proteins and enzyme activity, but not messenger ribonucleic acid, in the monkey corpus luteum during the menstrual cycle

Marina C. Peluffo, Kelly A. Young, Richard Stouffer

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    26 Scopus citations


    Studies were designed to determine whether: 1) changes in caspase expression or activity occur in the macaque corpus luteum (CL) during its lifespan in the menstrual cycle, and 2) LH acting directly or via ovarian steroids regulates luteal caspases. Caspase-2, -3, -8, and -9 mRNAs were detectable by semiquantitative RT- or real time-PCR in CL, but levels did not differ between the early, mid, mid-late, late, and very-late luteal phases. Immunostaining for caspase-2 and -3 proteins was observed in luteal cells and appeared to peak by mid to mid-late stage. Enzyme activity for caspase-2, -3, -8, and -9 increased (P <0.05) by mid-late stage, and then declined by the very-late stage. Treatment with GnRH antagonist + LH at the mid-late stage increased caspase-2, -8, and -9, but not -3, activity, compared with controls. Coadministration of a steroid synthesis inhibitor (trilostane) with GnRH antagonist + LH reduced (P <0.05) caspase-2, -8, and -9 activity. Progestin (R5020) replacement during trilostane treatment did not restore caspase activity. Thus, initiator and effector caspases are present during CL development and regression in the menstrual cycle. The increased caspase activity at mid-late stage suggests that apoptosis is involved in early luteolysis in primates. Gonadotropin, perhaps via local steroids, modulates initiator caspases in the primate CL.

    Original languageEnglish (US)
    Pages (from-to)2327-2335
    Number of pages9
    JournalJournal of Clinical Endocrinology and Metabolism
    Issue number4
    Publication statusPublished - Apr 2005


    ASJC Scopus subject areas

    • Biochemistry
    • Endocrinology, Diabetes and Metabolism

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