title: Expression of obesity markers and Persistent Organic Pollutants levels in adipose tissue of obese patients: reinforcing the obesogen hypothesis?
abstract: BACKGROUND
  Persistent Organic Pollutants (POPs) accumulate in adipose tissue and some are described to possess endocrine disrupting capacities. Therefore, it is important to evaluate their effects on key endocrine pathways in adipose tissue (AT), to further evaluate their potential role in metabolic pathologies such as obesity.
  
  
  OBJECTIVE
  THE AIM IS TWOFOLD: (i) evaluate gene expression levels of obesity marker genes, i.e. the adipokines leptin (LEP), adiponectin (ADIPOQ) and Tumor Necrosis Factor α (TNFα) and the nuclear receptor, Peroxisome Proliferator Activated Receptor γ (PPARγ) in paired subcutaneous (SAT) and visceral (VAT) AT of obese subjects (n = 50) and to relate these values to serum concentrations of LEP and ADIPOQ (ii) evaluate the association of expression levels of marker genes in AT and serum with POP concentrations in AT.
  
  
  CONCLUSIONS
  Leptin and adiponectin levels in serum were positively correlated to respectively expression levels of leptin in SAT and adiponectin in VAT. Our study shows more significant correlations between gene expression of obesity marker genes and POP concentrations in VAT compared to SAT. Since VAT is more important than SAT in pathologies associated with obesity, this suggests that POPs are able to influence the association between obesity and the development of associated pathologies. Moreover, this finding reveals the importance of VAT when investigating the obesogen hypothesis. Concerning PPARγ expression in VAT, negative correlations with polychlorinated biphenyls (PCBs) concentrations were found in non T2D patients. LEP serum concentrations correlated with several PCBs in women whereas in men no correlations were found. This strengthens the potential importance of gender differences in obesity and within the obesogen hypothesis.
authors.affiliation: Systemic Physiological and Ecotoxicological Research (SPHERE), Department of Biology, University of Antwerp, Antwerp, Belgium.
authors.forename: Anna
authors.initials: A
authors.lastname: Pereira-Fernandes
authors.affiliation: Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, University of Antwerp, Edegem, Belgium.
authors.forename: Eveline
authors.initials: E
authors.lastname: Dirinck
authors.affiliation: Toxicological Centre, University of Antwerp, Antwerp, Belgium.
authors.forename: Alin C
authors.initials: AC
authors.lastname: Dirtu
authors.affiliation: Toxicological Centre, University of Antwerp, Antwerp, Belgium.
authors.forename: Govindan
authors.initials: G
authors.lastname: Malarvannan
authors.affiliation: Toxicological Centre, University of Antwerp, Antwerp, Belgium.
authors.forename: Adrian
authors.initials: A
authors.lastname: Covaci
authors.affiliation: Department of Endocrinology, Diabetology and Metabolism, Antwerp University Hospital, University of Antwerp, Edegem, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Van Gaal
authors.affiliation: Systemic Physiological and Ecotoxicological Research (SPHERE), Department of Biology, University of Antwerp, Antwerp, Belgium.
authors.forename: Caroline
authors.initials: C
authors.lastname: Vanparys
authors.affiliation: Department of Clinical Pharmacology, Antwerp University Hospital, University of Antwerp, Edegem, Belgium.
authors.forename: Philippe G
authors.initials: PG
authors.lastname: Jorens
authors.affiliation: Systemic Physiological and Ecotoxicological Research (SPHERE), Department of Biology, University of Antwerp, Antwerp, Belgium.
authors.forename: Ronny
authors.initials: R
authors.lastname: Blust
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D050152:Intra-Abdominal Fat / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics* / Q000378:metabolism*; D050151:Subcutaneous Fat / Q000378:metabolism; D055815:Young Adult
chemical_list: D015415:Biomarkers