The flower of Edgeworthia gardneri (wall.) Meisn. suppresses adipogenesis through modulation of the AMPK pathway in 3T3-L1 adipocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: The flower of Edgeworthia gardneri (Wall.) Meisn., locally named "Lvluohua, ", has been widely used as Tibetan folk medicine for the treatment of metabolic diseases for a long time. AIM OF THIS STUDY: To evaluate the anti-adipogenesis effect of ethyl acetate extract of the flower of E. gardneri (EEG extract) in 3T3-L1 adipocytes. MATERIALS AND METHODS: Obesity-related parameters such as lipid accumulation and TG content were determined by Oil red O staining and enzymatic kit, respectively. Western blotting was used to determine the expressions of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein-α (C/EBPα), phosphorylated adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC). Moreover, main constituents of EEG extract were analyzed by high performance liquid chromatography (HPLC). RESULTS: EEG extract decreased the lipid and triglyceride (TG) accumulations during the differentiation process and down-regulated the adipogenesis-related transcriptional factors PPARγ and C/EBPα. EEG extract treatment increased AMPK and ACC phosphorylation. In addition, pretreatment with AMPK inhibitor, weakened the inhibitory effects of EEG extract on the expressions of PPARγand C/EBPα. HPLC analysis indicated that tiliroside was the main constituent in EEG extract. CONCLUSIONS: These results suggest that EEG extract may exert anti-adipogenic effects through modulation of the AMPK signaling pathway.

In vitro evaluation of dual agonists for PPARγ/ß from the flower of Edgeworthia gardneri (wall.) Meisn.

ETHNOPHARMACOLOGICAL RELEVANCE: In Tibet, the flower of Edgeworthia gardneri (Wall.) Meisn., locally named "Lvluohua, [symbols: see text]", has been traditionally used to treat diabetes mellitus for many years. AIM OF THIS STUDY: To evaluate the activity of dual agonists for PPARγ/ß from the flower of E.gardneri in vitro. MATERIALS AND METHODS: HeLa cells were transiently co-transfected with the re-constructed plasmids of pBIND-PPARγ-LBD or pBIND-PPARß-LBD and rL4.35. The activities of crude extracts, secondary fractions and compounds from the flower of E.gardneri were evaluated with the transfected cells. Rosiglitazone (at 0.5 µg/mL) and L-165041 (at 0.5 µg/mL) were used as the positive controls for PPARγ and PPARß respectively. RESULTS: The results demonstrated that n-hexane, ethyl acetate and n-butanol extracts from the flower of E.gardneri were able to significantly activate PPARγ and PPARß respectively, and the activity of ethyl acetate extract was much better. We further observed that, among the 11 secondary fractions of ethyl acetate extract, the fr. 9 could activate PPARγ and PPARß significantly. Moreover, umbelliferone (from fr.9) and pentadecanoic acid could activate PPARγ and PPARß at the same time. CONCLUSIONS: The extracts from the flower of E.gardneri could significantly activate PPARγ and PPARß. Besides, umbelliferone and pentadecanoic acid isolated from the flower of E.gardneri were the new agonists for PPARγ and PPARß.