title: High fat diet impact on Fos expression in ovariectomized female C57BL/6 mice: effect of colchicine and response of different neuronal phenotypes.
abstract: OBJECTIVE
  Activity of neuropeptide Y (NPY), tyrosine hydroxylase (TH), corticoliberine (CRH), and oxytocin (OXY) producing cells was investigated in the ovariectomized (OVX) female C57BL/6 mice kept on the high fat diet for 16 weeks and their response to colchicine stress in selected brain areas, including the hypothalamic paraventricular (PVN), dorsomedial (DMN) and arcuate (ARC) nuclei, A1/C1 (in the ventrolateral medulla), and A2/C2 (in the nucleus of the solitarii tract, NTS) catecholaminergic cell groups.
  
  
  METHODS
  The OVX female C57BL/6 mice kept on high fat diet were sacrificed by transcardial perfusion with fixative 48 h after intracerebroventricular injection of colchicine (18 µg mice). Dual Fos/neuropeptide immunohistochemistry was employed to investigate Fos/neuropeptide colocalizations.
  
  
  RESULTS
  In the OVX saline-treated mice (sham control) with standard diet (St diet), no immunopositive CRH and NPY neurons were identified in the PVN and weak Fos immunostainig was visible in TH neurons in the DMN and ARC nuclei. Colchicine treatment in the OVX mice with St diet increased the number of CRH and OXY immunopositive neurons in the PVN as well as the number of NPY and TH neurons in DMN and ARC nuclei and NPY neurons in the middle NTS (mNTS) and A1/C1 cell group. Prolonged HF diet in OVX sham control mice moderately increased the number of Fos/TH neurons in the mNTS and commissural NTS (cNTS) in comparison with St diet mice. However, prolonged HF diet in OVX colchicines-treated mice reduced the number of Fos/NPY neurons in the anterior NTS (aNTS) and A1/C1 cell group in comparison with colchicines-treated animals with St diet as well as Fos-TH neurons in the mNTS and cNTS in comparison with saline-treated animals with HF diet.
  
  
  CONCLUSIONS
  The data of this pilot study indicate that prolonged high fat diet might: 1) represent itself a light/moderate stimulus for activation of TH neurons in the NTS and A1/C1 cell group as well as NPY neurons in the A1/C1 cell group and 2) interfere with colchicines-induced and time-delayed Fos activation in the NPY and TH neurons in both the above mentioned brain nuclei.
authors.affiliation: Slovak Academy of Sciences, Bratislava, Slovak Republic.
authors.forename: Z
authors.initials: Z
authors.lastname: Pirnik
authors.forename: J
authors.initials: J
authors.lastname: Bundzikova
authors.forename: A
authors.initials: A
authors.lastname: Kiss
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000166:cytology / Q000187:drug effects; D003078:Colchicine / Q000633:toxicity*; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism; D004041:Dietary Fats / Q000494:pharmacology*; D004302:Dorsomedial Hypothalamic Nucleus / Q000166:cytology / Q000187:drug effects; D005260:Female; D007031:Hypothalamus / Q000166:cytology / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D010052:Ovariectomy; D010121:Oxytocin / Q000378:metabolism; D010286:Paraventricular Hypothalamic Nucleus / Q000166:cytology / Q000187:drug effects; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D050257:Tubulin Modulators / Q000633:toxicity; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: D004041:Dietary Fats; D009478:Neuropeptide Y; D016760:Proto-Oncogene Proteins c-fos; D050257:Tubulin Modulators; D010121:Oxytocin; D003346:Corticotropin-Releasing Hormone; D014446:Tyrosine 3-Monooxygenase; D003078:Colchicine