Rutaecarpine Analogues Reduce Lipid Accumulation in Adipocytes via Inhibiting Adipogenesis/Lipogenesis with AMPK Activation and UPR Suppression

Abstract

Obesity is characterized by expansion of adipose tissue, which results from an increase in adipocyte number (adipogenesis) and adipocyte size (lipogenesis). A reversal of these processes has been suggested to be a potential antiobetic therapy. Rutaecarpine (Rut) and its novel analogues (R17 and R18) were identified to exert potent effect in reducing lipid accumulation during adipocyte differentiation in 3T3-L1 adipocytes with little cytotoxicity. All three compounds reduced lipid accumulation in a dose-dependent manner, while R17 and R18 exhibited much more potent inhibitory effects compared to that of Rut. Further studies showed that R17 suppressed both adipogenesis and lipogenesis during all stages of adipocyte differentiation as indicated by the reduced protein and mRNA levels of key regulators of adipogenesis/lipogenesis, including PPARγ, C/EBPα, SREBP-1c, ACC, FAS, and SCD-1. We next examined the effect of R17 on the UPR pathway and the results showed that the UPR markers (PERK, eIF2α, IRE1α, and spliced XBP1 mRNA) were all significantly reduced by R17. Further studies revealed that R17 persistently activated AMPK during differentiation, suggesting that the AMPK may be an upstream mechanism for the effect of R17 on adipogenesis and lipogenesis via the adipogenic/lipogenic markers and the UPR pathway. Finally, studies in fast/refeeding mice demonstrated that R17 administration was able to reduce epididymal fat mass and the levels of plasma TG and FFA in vivo. Our results suggest that rutaecarpine analogues may have therapeutic potential for obesity and related metabolic disorders. The mechanism involves the suppression of adipogenic/lipogenic proteins and the suppression of the UPR pathway possibly via the AMPK.

Pyrocincholic acid 3β-O-β-d-quinovopyranosyl-28-O-β-d-glucopyranoside suppresses adipogenesis and regulates lipid metabolism in 3T3-L1 adipocytes

“…Cells were routinely cultured in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% CS and 1% P/S at 37 °C in a 5% CO 2 atmosphere [25]. For adipocytes differentiation, 2-day postconfluent cells (day 0) were placed in Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% FBS, 1% P/S, IBMX, DEX, insulin [26] and Rosi (designated hereafter as MDIR).…”

“…The second one: PAQG was added at day 5 and cells were harvested after 2 days treatment. The PAQG was dissolved in DMSO, 3T3-L1 cells cultured in DMEM supplemented with 0.1% DMSO were used as a vehicle control for all experiments [25]. …”

“…The Oil Red O working solution was prepared as described [25, 27]. At a word, 3T3-L1 cells were washed twice with phosphate-buffered saline (PBS) after removed the culture medium and were fixed in 10% formaldehyde at room temperature for 10 min, the 10% formaldehyde was discarded and new 10% formaldehyde was added for 1 h. Wash twice with water and one time with 60% isopropanol sequentially after fixing.…”

One-pot synthesis of quinazolin-4(3H)-ones and2,3-dihydroquinazolin-4(1H)-ones utilizingN-(2-aminobenzoyl)benzotriazoles

“…has been used for the treatment of malaria for more than 2000 years because it contains antimalarial active quinazolinone alkaloids, febrifugine and iso-febrifugine (lately, however, it was discontinued due to its toxic effects) [7]. Rutaecarpine, originally extracted from Evodia rutaecarpa, is a COX-2 inhibitor and has diverse pharmacological properties, including antithrombotic, anticancer, antiinflammatory and antiobesity activities [8][9][10][11]. Vasicinone is another quinazolinone alkaloid that was originally isolated from the leaves of Adhatoda vasica and has bronchodilatory activity [12].…”

Discovery of natural alkaloid bouchardatine as a novel inhibitor of adipogenesis/lipogenesis in 3T3-L1 adipocytes

“…These factors have important function in regulation of adipogenesis by modulating the expression of their target genes in a coordinated manner. [8][9][10][11][12] Moreover, AMPK is one of the most well-characterized and important targets for the prevention and treatment of obesity. [13][14][15][16] The AMPK complex is a heterotrimer composed of catalytic a subunit and regulatory b, c subunits.…”