title: High-throughput sequencing of microRNAs in peripheral blood mononuclear cells: identification of potential weight loss biomarkers.
abstract: BACKGROUND
  MicroRNAs (miRNAs) are being increasingly studied in relation to energy metabolism and body composition homeostasis. Indeed, the quantitative analysis of miRNAs expression in different adiposity conditions may contribute to understand the intimate mechanisms participating in body weight control and to find new biomarkers with diagnostic or prognostic value in obesity management.
  
  
  OBJECTIVE
  The aim of this study was the search for miRNAs in blood cells whose expression could be used as prognostic biomarkers of weight loss.
  
  
  METHODS
  Ten Caucasian obese women were selected among the participants in a weight-loss trial that consisted in following an energy-restricted treatment. Weight loss was considered unsuccessful when <5% of initial body weight (non-responders) and successful when >5% (responders). At baseline, total miRNA isolated from peripheral blood mononuclear cells (PBMC) was sequenced with SOLiD v4. The miRNA sequencing data were validated by RT-PCR.
  
  
  RESULTS
  Differential baseline expression of several miRNAs was found between responders and non-responders. Two miRNAs were up-regulated in the non-responder group (mir-935 and mir-4772) and three others were down-regulated (mir-223, mir-224 and mir-376b). Both mir-935 and mir-4772 showed relevant associations with the magnitude of weight loss, although the expression of other transcripts (mir-874, mir-199b, mir-766, mir-589 and mir-148b) also correlated with weight loss.
  
  
  CONCLUSIONS
  This research addresses the use of high-throughput sequencing technologies in the search for miRNA expression biomarkers in obesity, by determining the miRNA transcriptome of PBMC. Basal expression of different miRNAs, particularly mir-935 and mir-4772, could be prognostic biomarkers and may forecast the response to a hypocaloric diet.
authors: Department of Nutrition, Food Sciences and Physiology, University of Navarra, Pamplona, Spain.
authors: Fermín I
authors: FI
authors: Milagro
authors: Jonatan
authors: J
authors: Miranda
authors: María P
authors: MP
authors: Portillo
authors: Alfredo
authors: A
authors: Fernandez-Quintela
authors: Javier
authors: J
authors: Campión
authors: J Alfredo
authors: JA
authors: Martínez
mesh_terms: D000328:Adult; D001835:Body Weight / Q000235:genetics; D002874:Chromosome Mapping; D004038:Diet, Reducing; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005819:Genetic Markers; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics*; D017423:Sequence Analysis, RNA; D015431:Weight Loss / Q000235:genetics*
chemical_list: D005819:Genetic Markers; D035683:MicroRNAs