title: No evidence for neo-oogenesis may link to ovarian senescence in adult monkey.
abstract: Female germline or oogonial stem cells transiently residing in fetal ovaries are analogous to the spermatogonial stem cells or germline stem cells (GSCs) in adult testes where GSCs and meiosis continuously renew. Oocytes can be generated in vitro from embryonic stem cells and induced pluripotent stem cells, but the existence of GSCs and neo-oogenesis in adult mammalian ovaries is less clear. Preliminary findings of GSCs and neo-oogenesis in mice and humans have not been consistently reproducible. Monkeys provide the most relevant model of human ovarian biology. We searched for GSCs and neo-meiosis in ovaries of adult monkeys at various ages, and compared them with GSCs from adult monkey testis, which are characterized by cytoplasmic staining for the germ cell marker DAZL and nuclear expression of the proliferative markers PCNA and KI67, and pluripotency-associated genes LIN28 and SOX2, and lack of nuclear LAMIN A, a marker for cell differentiation. Early meiocytes undergo homologous pairing at prophase I distinguished by synaptonemal complex lateral filaments with telomere perinuclear distribution. By exhaustive searching using comprehensive experimental approaches, we show that proliferative GSCs and neo-meiocytes by these specific criteria were undetectable in adult mouse and monkey ovaries. However, we found proliferative nongermline somatic stem cells that do not express LAMIN A and germ cell markers in the adult ovaries, notably in the cortex and granulosa cells of growing follicles. These data support the paradigm that adult ovaries do not undergo germ cell renewal, which may contribute significantly to ovarian senescence that occurs with age.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, The 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics and College of Life Sciences, Nankai University, Tianjin, China; Key Laboratory of Ministry of Health on Hormones and Development, Metabolic Diseases Hospital, Tianjin Medical University, Tianjin, China.
authors.forename: Jihong
authors.initials: J
authors.lastname: Yuan
authors.forename: Dongdong
authors.initials: D
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Mengyuan
authors.initials: M
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Mao
authors.forename: Yu
authors.initials: Y
authors.lastname: Yin
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Ye
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.forename: Jihong
authors.initials: J
authors.lastname: Han
authors.forename: Yingdai
authors.initials: Y
authors.lastname: Gao
authors.forename: Tao
authors.initials: T
authors.lastname: Cheng
authors.forename: David L
authors.initials: DL
authors.lastname: Keefe
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
mesh_terms: D053687:Adult Stem Cells / Q000502:physiology*; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D016922:Cellular Senescence / Q000502:physiology; D005260:Female; D000882:Haplorhini; D008297:Male; D008540:Meiosis / Q000502:physiology; D051379:Mice; D009866:Oogenesis / Q000235:genetics*; D006080:Ovarian Follicle / Q000166:cytology; D010053:Ovary / Q000166:cytology / Q000378:metabolism / Q000502:physiology*
keywords: Aging; Germline stem cells; Meiosis; Monkey; Oogenesis; Ovary