title: Expression of a mitochondrial progesterone receptor in human spermatozoa correlates with a progestin-dependent increase in mitochondrial membrane potential.
abstract: The hyperactivation of human spermatozoa necessary for fertilization requires a substantial increase in cellular energy production. The factors responsible for increasing cellular energy remain poorly defined. This article proposes a role for a novel mitochondrial progesterone receptor (PR-M) in modulation of mitochondrial activity. Basic science studies demonstrate a 38 kDa protein with western blot analysis, consistent with PR-M; whereas imaging studies with confocal and immunoelectron microscopy demonstrate a PR on the mitochondria. Treatment with a PR-specific progestin shows increased mitochondrial membrane potential, not related to induction of an acrosome reaction. The increase in mitochondrial membrane potential was inhibited by a specific PR antagonist, but not affected by an inhibitor to the progesterone-dependent Catsper voltage-activated channel. In conclusion, these studies suggest expression of a novel mitochondrial PR in human spermatozoa with a progestin-dependent increase in mitochondrial activity. This mechanism may serve to enhance cellular energy production as the spermatozoa traverse the female genital tract being exposed to increasing concentrations of progesterone.
authors.affiliation: Department of Obstetrics and Gynecology, Duke University, Durham, NC, USA.
authors.forename: J
authors.initials: J
authors.lastname: Tantibhedhyangkul
authors.forename: K C
authors.initials: KC
authors.lastname: Hawkins
authors.forename: Q
authors.initials: Q
authors.lastname: Dai
authors.forename: K
authors.initials: K
authors.lastname: Mu
authors.forename: C N
authors.initials: CN
authors.lastname: Dunn
authors.forename: S E
authors.initials: SE
authors.lastname: Miller
authors.forename: T M
authors.initials: TM
authors.lastname: Price
mesh_terms: D006801:Humans; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D008856:Microscopy, Fluorescence; D016253:Microscopy, Immunoelectron; D008928:Mitochondria / Q000378:metabolism*; D011372:Progestins / Q000494:pharmacology*; D011980:Receptors, Progesterone / Q000378:metabolism*; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D011372:Progestins; D011980:Receptors, Progesterone
keywords: human spermatozoa; immunocytochemistry; immunoelectron microscopy; mitochondrial membrane potential; mitochondrial progesterone receptor