title: Fractalkine is expressed in the human ovary and increases progesterone biosynthesis in human luteinised granulosa cells.
abstract: BACKGROUND
  Recent evidence from rodent ovaries has demonstrated expression of fractalkine and the existence of fractalkine receptor, and showed that there is a significant increase in steroidogenesis in response to fractalkine, yet the role of fractalkine and CX3CR1 in the human ovary is still unknown. This study aimed to determine the expression levels of fractalkine and CX3CR1 in the human ovary and to investigate their roles in sexual hormone biosynthesis by human luteinising granulosa cells. This is the first detailed report of fractalkine and CX3CR1 expression and function in the human ovary.
  
  
  METHODS
  Fractalkine and CX3CR1 expression levels were measured by immunohistochemistry using ovarian tissue from pathological specimens from five individuals. Granulosa cells were obtained from patients during IVF treatment. They were cultured and treated with increasing doses of hCG with or without fractalkine. Media were collected to detect estradiol and progesterone by chemiluminescence. StAR, 3-βHSD and CYP11A expression were determined in granulosa cells treated with or without fractalkine by real-time RT-PCR.
  
  
  RESULTS
  Fractalkine and CX3CR1 were expressed in the human ovary and in luteinising granulosa cells. However, fractalkine expression was stronger in luteinising granulosa cells. Treatment with fractalkine augmented hCG stimulation of progesterone production in a dose-dependent manner with concomitant increases in transcript levels for key steroidogenic enzymes (StAR, 3-βHSD and CYP11A) but had no effect on estradiol biosynthesis (P<0.05).
  
  
  CONCLUSIONS
  Fractalkine and CX3CR1 were found to express in human ovary and luteinising granulosa cells. Fractalkine can increase the biosynthesis of progesterone in a dose-dependent manner by enhancing transcript levels of key steroidogenic enzymes.
authors: Reproductive Medical Center, Peking University Third Hospital, Beijing, People's Republic of China.
authors: Shuo
authors: S
authors: Huang
authors: Ping
authors: P
authors: Zhao
authors: Liying
authors: L
authors: Yang
authors: Yuan
authors: Y
authors: Chen
authors: Jie
authors: J
authors: Yan
authors: Enkui
authors: E
authors: Duan
authors: Jie
authors: J
authors: Qiao
mesh_terms: D000328:Adult; D000073883:CX3C Chemokine Receptor 1; D002478:Cells, Cultured; D054428:Chemokine CX3CL1 / Q000096:biosynthesis*; D005260:Female; D006107:Granulosa Cells / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D010053:Ovary / Q000378:metabolism*; D011374:Progesterone / Q000096:biosynthesis*; D019707:Receptors, Chemokine / Q000096:biosynthesis*
chemical_list: D000073883:CX3C Chemokine Receptor 1; C095235:CX3CR1 protein, human; D054428:Chemokine CX3CL1; D019707:Receptors, Chemokine; D011374:Progesterone