title: Identification of microRNAs in human follicular fluid: characterization of microRNAs that govern steroidogenesis in vitro and are associated with polycystic ovary syndrome in vivo.
abstract: BACKGROUND
  Human follicular fluid is a combination of proteins, metabolites, and ionic compounds that is indicative of the general state of follicular metabolism and is associated with maturation and quality of oocytes. Deviations in these components are often associated with reproductive diseases. There has been no report of microRNAs (miRNAs) in human follicular fluids.
  
  
  OBJECTIVE
  We hypothesized that human follicular fluid may contain miRNAs. We sought to identify cell-free miRNAs in human follicular fluid and to investigate the function of these miRNAs in vitro and any roles they play in polycystic ovary syndrome (PCOS).
  
  
  METHODS
  Genome-wide deep sequencing and TaqMan miRNA arrays were used to identify miRNAs, and the roles of the highly expressed miRNAs in steroidogenesis were investigated in KGN cells. Quantification of candidate miRNAs in follicular fluids of PCOS and controls was performed using TaqMan miRNA assays.
  
  
  RESULTS
  We identified miRNAs in microvesicles and the supernatant of human follicular fluid. Bioinformatics analysis showed that the most highly expressed miRNAs targeted genes associated with reproductive, endocrine, and metabolic processes. We found that miR-132, miR-320, miR-520c-3p, miR-24, and miR-222 regulate estradiol concentrations and that miR-24, miR-193b, and miR-483-5p regulate progesterone concentrations. Finally, we showed that miR-132 and miR-320 are expressed at significantly lower levels in the follicular fluid of polycystic ovary patients than in healthy controls (P = .005 and P = .0098, respectively).
  
  
  CONCLUSIONS
  These results demonstrate that there are numerous miRNAs in human follicular fluids, some of which play important roles in steroidogenesis and PCOS. This study substantially revises our understanding of the content of human follicular fluid and lays the foundation for the future investigation of the role of miRNAs in PCOS.
authors.affiliation: State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences, and Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Sang
authors.forename: Zhongyuan
authors.initials: Z
authors.lastname: Yao
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.forename: Ruizhi
authors.initials: R
authors.lastname: Feng
authors.forename: Haojue
authors.initials: H
authors.lastname: Wang
authors.forename: Xinzhi
authors.initials: X
authors.lastname: Zhao
authors.forename: Qinghe
authors.initials: Q
authors.lastname: Xing
authors.forename: Li
authors.initials: L
authors.lastname: Jin
authors.forename: Lin
authors.initials: L
authors.lastname: He
authors.forename: Lingqian
authors.initials: L
authors.lastname: Wu
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
mesh_terms: D000328:Adult; D002460:Cell Line; D015331:Cohort Studies; D019295:Computational Biology; D045166:Estradiol Congeners / Q000378:metabolism*; D005260:Female; D015571:Follicular Fluid / Q000378:metabolism*; D006107:Granulosa Cells / Q000378:metabolism; D006801:Humans; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010053:Ovary / Q000378:metabolism*; D011085:Polycystic Ovary Syndrome / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D015398:Signal Transduction; D014162:Transfection; D022161:Transport Vesicles / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D045166:Estradiol Congeners; D035683:MicroRNAs; C549214:MIRN19A microRNA, human; C525710:MIR222, human; C543845:MIRN24 microRNA, human