Citrus aurantium L. dry extracts promote C/ebpβ expression and improve adipocyte differentiation in 3T3-L1 cells

Abstract

Metabolic and/or endocrine dysfunction of the white adipose tissue (WAT) contribute to the development of metabolic disorders, such as Type 2 Diabetes (T2D). Therefore, the identification of products able to improve adipose tissue function represents a valuable strategy for the prevention and/or treatment of T2D. In the current study, we investigated the potential effects of dry extracts obtained from Citrus aurantium L. fruit juice (CAde) on the regulation of 3T3-L1 cells adipocyte differentiation and function in vitro. We found that CAde enhances terminal adipocyte differentiation of 3T3-L1 cells raising the expression of CCAAT/enhancer binding protein beta (C/Ebpβ), peroxisome proliferator activated receptor gamma (Pparγ), glucose transporter type 4 (Glut4) and fatty acid binding protein 4 (Fabp4). CAde improves insulin-induced glucose uptake of 3T3-L1 adipocytes, as well. A focused analysis of the phases occurring in the pre-adipocytes differentiation to mature adipocytes furthermore revealed that CAde promotes the early differentiation stage by up-regulating C/ebpβ expression at 2, 4 and 8 h post the adipogenic induction and anticipating the 3T3-L1 cell cycle entry and progression during mitotic clonal expansion (MCE). These findings provide evidence that the exposure to CAde enhances in vitro fat cell differentiation of pre-adipocytes and functional capacity of mature adipocytes, and pave the way to the development of products derived from Citrus aurantium L. fruit juice, which may improve WAT functional capacity and may be effective for the prevention and/or treatment of T2D.

Citrus aurantium L. Dry Extracts Ameliorate Adipocyte Differentiation of 3T3-L1 Cells Exposed to TNFα by Down-Regulating miR-155 Expression

“…Indeed, an increasing number of studies have reported that several natural food-derived compounds modulate miRNA expression in different animal cells and tissues [24][25][26]. Extracts from Citrus aurantium L. have been recently used for investigating adipocyte differentiation [28,42,43]. However, quite different results have been obtained, and whether or not extracts from Citrus aurantium L. have pro-or anti-adipogenic properties is still unclear.…”

“…As well as this, nutraceuticals are known to regulate adipocyte cell line activity [ 27 ]. In line with this, we have recently demonstrated the nutraceutical properties of CA de, a dry extract preparation obtained from Citrus aurantium L. ( CA de) fruit juice, on the regulation of 3T3-L1 cell adipocyte differentiation and function [ 28 ]. CA de enhances in vitro terminal adipocyte differentiation of 3T3-L1 pre-adipocytes in terms of increased gene expression of Pparγ , glucose transporter type 4 ( Glut4 ), and fatty acid-binding protein 4 ( Fabp4 ), as well as the functional capacity of 3T3-L1 mature adipocytes in terms of improved insulin-induced glucose uptake [ 28 ].…”

“…Citrus aurantium L. ( CA de) fruit juice dry extracts were from [ 28 ]. Lyophilized CA de was re-hydrated with distilled H 2 O to a final concentration of 10 mg/mL and used for treatments at the concentration of 100 μg/mL.…”

“…WB analysis was performed as described in [ 28 ]. 3T3-L1 cell lysates were obtained by lysing cells in buffer containing 20 mm Tris-HCl, pH 7.5; 5 mm Ethylenediaminetetraacetic acid (EDTA); 150 mm NaCl; 1% Nonidet P40 (NP40), 10 μm phenylmethylsulfonyl fluoride (PMSF); 5 μg/mL aprotinin; and 5 μg/mL leupeptin.…”

“…CA de enhances in vitro terminal adipocyte differentiation of 3T3-L1 pre-adipocytes in terms of increased gene expression of Pparγ , glucose transporter type 4 ( Glut4 ), and fatty acid-binding protein 4 ( Fabp4 ), as well as the functional capacity of 3T3-L1 mature adipocytes in terms of improved insulin-induced glucose uptake [ 28 ]. Furthermore, CA de promotes the early differentiation stage as well, by anticipating the 3T3-L1 cell cycle entry and progression during mitotic clonal expansion and by activating CREB and nearly doubling the expression of the transcription factor C/Ebpβ a few hours later in the adipogenic induction [ 28 ].…”