DISTORTED IN VITRO ADIPOGENIC CAPACITY IN STROMAL-VASCULAR FRACTION (SVF) CELLS FROM HYPOTHALAMIC OBESE MALE RATS

ZUBIRÍA G,; VIDAL BRAVO, J; GAILLARD, R.C; SPINEDI E; GIOVAMBATTISTA A

San Diego, California

Congreso; Obesity 2010 28th Annual Scientific Meeting; 2010

The Obesity Society

Distorted in vitro adipogenic capacity in stromal-vascular fraction (SVF) cells from hypothalamic obese male rats Adipogenesis involves preadipocyte differentiation into mature adipocyte, and is regulated by endocrine/paracrine signals. We currently evaluated the adipogenic capacity in SVF cells from adult control (CTR) and hyperadipose (due to neonatal L-monosodium glutamate treatment; MSG) male rats. The peripheral levels of leptin (LEP), insulin (INS) and corticosterone (B) were determined. Also, isolated SVF cells from retroperitoneal adipose tissue origin, were induced to differentiate in culture up to 10 days. Before starting differentiation, preadipocyte factor-1 (Pref-1) mRNA was quantified (by RT-PCR real time) in confluent preadipocytes. On day 10 post-differentiation, the culture medium was removed (to measure LEP concentration) and, intracellular lipid content (Oil-Red O) and gene expression (LEP, PPARg, and AIPOQ mRNA levels) were determined. Cell vacuole area and cell nucleus position were measured. MSG rats displayed high plasma LEP and B levels (p<0.05 vs. CTR), whereas INS remained normal. Before induction of differentiation, MSG SVF cells revealed a high (p<0.05 vs. CTR) Pref-1 mRNA expression. On day 10 post-differentiation, MSG cells showed diminished (p<0.05 vs. CTR) LEP release into the medium, lipid content and, mRNA levels of LEP and PPARg. Additionally, low cell vacuole area and diminished percentage of cells with nucleus situated at the periphery were characteristics of MSG cells. Our study suggests that in the male rat MSG, the in vitro adipogenic process pattern seems to be shifted to the left. Thus, it could be speculated that a leptin- and glucocorticoid-rich endogenous environment could be responsible, at least in part, for distorting adipogenesis in the MSG rat.