Progesterone Induces Production of Reactive Oxygen Species in a Bovine Granulosa Cell Line

Abstract

In cattle, low progesterone (P4) concentrations have been linked to anovulation. To study the local effects of P4 on granulosacells, in the present study we aimed: (a) to characterise the expression of receptors (progesterone receptor (PR), oestrogen receptorsα and β (ERα and β), FSH receptor (FSHR) and LH receptor (LHR)), as well as the co-expressionof PR and signal transducerand activator of transcription 5 (STAT5) and a cytochrome P450 aromatase A1 (CYP19A1), in a bovine granulosa cell line(BGC-1)sensitive to P4 stimuli; and (b) to evaluate the effects of P4 on cell viability, apoptosis and reactive oxygen species (ROS)production in BGC-1cells after 12, 24 and 48 h of stimulation. BGC-1cells expressed CYP19A1, as well as ERα and β, PR, FSHRand LHR. The mean fluorescence intensity of STAT5 and PR and the percentage of simple and double-positivecells (STAT5/PR)were lower in control cells than in P4-stimulatedcells after 12, 24, and 48 h of stimulation. Regarding the effects of P4 on cellviability, after 12, 24, and 48 h of stimulation, the percentage of living cells was high and the number of apoptotic and necroticcells was low. Finally, BGC-1cells responded to P4 stimulation by stimulating ROS production, without inducing damage. Theseresults support the potential use of P4-stimulatedBCG-1cells to study the mechanisms underlying follicular persistence in cows.