Distorted adipogenic capacity of isolated stromal-vascular fraction (SVF) cells from hyperadipose male rats

ZUBIRIA G; VIDAL BRAVO J; GAILLARD RC; SPINEDI E; GIOVAMBATTISTA A

San Diego

Congreso; Obesity 2010 28th Annual Scientific Meeting; 2010

The Obesity Society

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 (neonatally-treated with L-monosodium glutamate; 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 (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 ADIPOQ mRNA levels) were measured. Cell parameters, such as cell vacuole area and cell nucleus position were determined. 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, but not those of ADIPOQ. Additionally, low cell vacuole area and diminished percentage of cells with nucleus situated at the periphery characterized MSG cells. Our study suggests that in the male MSG rat, the in vitro adipogenic process pattern seems to be somewhat shifted to the left. Whether the leptin- and glucocorticoid-rich endogenous environment could be responsible for distorted adipogenesis in MSG rat requires a deeper research.