Evaluation of anti-adipogenic active homoisoflavonoids from Portulaca oleracea

This study was performed to isolate antiobesity components from the crude extract of Portulaca oleracea. The crude extract was partitioned into n-hexane, 85% aqueous methanol, n-butanol, and water fractions. Their effects on adipogenic differentiation were evaluated in 3T3-L1 cells. Among the solvent fractions from P. olearacea, the 85% aq. MeOH effectively reduced the levels of lipid accumulation. Further purification of 85% aq. MeOH led to the isolation of the known homoisoflavonoids 1-4, as the active substances. The administration of homoisoflavonoids to adipocyte cells decreased the lipid accumulation and glucose consumption and increased the release of glycerol into culture medium. In particular, homoisoflavonoid 3 effectively down-regulated the adipogenic transcription genes such as peroxisome proliferator activated receptor-gamma (PPAR gamma) and CCAAT/enhancer-binding proteins (C/EBP alpha), and adipogenic target genes such as fatty acid binding protein 4 (FABP4), fatty acid transport protein 1 (FATP1), and acyl-CoA synthase 1 (ACS1).