title: Diet-induced variability of the resistin gene (Retn) transcript level and methylation profile in rats.
abstract: BACKGROUND
  Adipose tissue is recognized as a highly active metabolic and endocrine organ. The hormones secreted by this tissue play an important role in many biochemical processes. It is known that dysfunction of adipocytes can cause insulin resistance, type 2 diabetes or hyperlipidemia. One of the important factors produced in fat tissue is resistin (Retn). It has been postulated that this hormone is involved in glucose homeostasis and insulin resistance. In the present study, the impact of five diet types (ad libitum normal, restricted, high-carbohydrate, high-fat and high-protein) on the Retn gene transcription and methylation profile was evaluated in rats of different ages.
  
  
  RESULTS
  Transcript levels and methylation status of the Retn gene were studied in three tissues (muscle, subcutaneous and abdominal fat) in rats at 30, 60 and 120 days of age. We found an effect of tissue type on the Retn transcription in all diet types, as well as an effect of feeding type and age on the mRNA levels for high-fat and high-protein diets. The DNA methylation levels depended only on tissue type.
  
  
  CONCLUSIONS
  The obtained results demonstrate a tissue-specific expression pattern and a characteristic DNA methylation profile of the Retn gene in rats. Retn expression seems to be sensitive to nutritional changes, but only in the case of high-fat and high-protein diets. Moreover, an effect of age on Retn mRNA content was observed in these diets. Because no correlation between the transcript level and methylation status was found, we assumed that the transcription control of this gene by DNA methylation of the promoter seems to be unlikely.
authors.affiliation: Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Wolynska 33, 60-637, Poznan, Poland. jnowacka@up.poznan.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Nowacka-Woszuk
authors.affiliation: Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Wolynska 35, Poznan, 60-637, Poland. ewaprusz@up.poznan.pl.
authors.forename: Ewa
authors.initials: E
authors.lastname: Pruszynska-Oszmalek
authors.affiliation: Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Wolynska 33, 60-637, Poznan, Poland. maciej@up.poznan.pl.
authors.forename: Maciej
authors.initials: M
authors.lastname: Szydlowski
authors.affiliation: Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Wolynska 33, 60-637, Poznan, Poland. slawek87@up.poznan.pl.
authors.forename: Slawomir
authors.initials: S
authors.lastname: Sadkowski
authors.affiliation: Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Wolynska 33, 60-637, Poznan, Poland. izabel@up.poznan.pl.
authors.forename: Izabela
authors.initials: I
authors.lastname: Szczerbal
mesh_terms: D024506:5' Flanking Region / Q000235:genetics; D000375:Aging / Q000235:genetics; D000818:Animals; D020029:Base Pairing / Q000235:genetics; D001483:Base Sequence; D019175:DNA Methylation / Q000235:genetics*; D004032:Diet; D004040:Dietary Carbohydrates; D008297:Male; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017208:Rats, Wistar; D052243:Resistin / Q000235:genetics* / Q000378:metabolism
chemical_list: D004040:Dietary Carbohydrates; D012333:RNA, Messenger; D052243:Resistin