WCP2018 OR28-3 Oral session White-to-brown adipose differentiation: role of beta and the isoflavone genistein

Alessandra Bitto, Federica Mannino, Natasha Irrera, Giovanni Pallio, Domenica Altavilla, Francesco Squadrito

Clinical and experimental medicine, University of Messina, Italy

The two types of fat cells in mammals brown and white have different functions. White (WAT) stores excess energy in the form of triglyceride and releases free fatty acids during caloric deficiency. (BAT) on the other hand can dissipate energy through thermogenesis. Genistein can have an effect on energy expenditure UCP (uncoupling ) expression and protect against the obesogenic effect of a high calorie diet. The effect of genistein in inducing white-to-brown transdifferentiation was investigated in 3T3-L1 cells differentiated into white adipocytes with a specific medium (DMEM 10% calf serum 1% penicillin/streptomycin 500 uM 3isobutyl1 methylxanthine 10ug/ml insulin 250 nM dexmethasone 8 ug/ml biotin and 4 ug/ml pantothenic acid). Fully differentiated white adipocytes were treated after 10 days with different genistein doses (10-50-100-200 uM) for 24-48h or left untreated. Two specific ER-beta and PPAR-gamma receptor inhibitors were also used to understand if genistein effects are mediated by the estrogen or the PPAR receptor. Also a CRISPR/Cas9 approach was used to delete either ER-beta or PPAR-gamma to clarify which receptor is involved in genistein action. Intracellular lipid accumulation was determined by oil-red-O staining after 24 and 48hours of treatment. The expression of UCP1 and beta PPARalpha and gamma DIO2 (Type II iodothyronine deiodinase) PRDM16 (PR domain containing 16) and CIDEA (cell death inducing DNA fragmentation factor) were evaluated by qPCR after 24 and 48hours of genistein treatment. Genistein significantly reduced lipid accumulation in adipose cells and affected the expression of the specific browning related thus suggesting a role for this isoflavone as a browning agent.