Gene Expression Assessment of the Polycomb Trithorax Complexes in the Brain of Fat-Tissue- Implanted Polycystic-Ovarian-Sindrome Mice

摘要

The Polycystic Ovary Syndrome (PCOS) is the most common androgenic disorder in women duringreproductive life. PCOS may also be accompanied by metabolic syndrome and recent studies point to leptin asplaying a role in disrupting infertility and in changing the energy balance in obese mice through its action on thehypothalamus. To assess the expression of the Polycomb & Trithorax Complexes genes in brain of micetransplanted with fat tissue from normal mice, in order to better understand the neuronal mechanisms underlyingthe reversion of PCOS. Three B6 V-Lepob/J mouse groups: normal weight, obese and seven-day-treatmentobese had their brain RNA extracted and submitted to an 84 Polycomb & Trithorax Complexes genes PCRArray plate and MetacoreTM pathways localization. Genomic profiles obtained were compared to the ones of thenormal-weight-mice group. Differentially expressed genes were 13% and 26% respectively to control andtreatment. Major changes were in genes: Snai1/31; Smarca1/-17; Dnmt3b/4.7; Ezh1/15. Altered genes wereassociated to canonical pathways and provided 3 networks related to epigenetics. Underlying neuronal changescaused by leptin in obese mice brain, there is an important role being played by the histone code. Here there isevidence that leptin drives the chromatin packing to a more condensed pattern. Upregulation ofmethyltransferase genes, like Ezh1, favors this thought. In summary the Polycomb & Trithorax complexes mightanswer for the silencing of some downregulated genes in the obese mice brain when exposed to leptin, like Neu4and Scg2.