title: St. John's wort promotes adipocyte differentiation and modulates NF-κB activation in 3T3-L1 cells.
abstract: St. John's wort (SJW), or Hypericum perforatum, is a perennial herb that has been used in the treatment of depression in several countries. Though its therapeutic effect on depression has been extensively studied, its influence on metabolic syndrome is yet to be fully characterized. Therefore, we investigated the effect of SJW extract on adipocyte differentiation and its anti-inflammatory effects by using 3T3-L1 preadipocytes. Oil Red O staining indicated that SJW promotes adipocyte differentiation, while immunoblots indicated that SJW increases the expression of peroxisome proliferator activated receptor γ (PPARγ), a nuclear receptor regulating adipocyte differentiation, and adiponectin, an anti-inflammatory adipokine. Furthermore, the anti-inflammatory activity of SJW was demonstrated by its inhibition of the activation of nuclear factor-κB (NF-κB), an inflammatory transcription factor. Stimulation of mature 3T3-L1 adipocytes by tumor necrosis factor-α (TNF-α) decreased the expression of the NF-κB inhibitor IκBα, and increased its phosphorylation. Treatment with SJW further decreased the TNF-α-induced perturbation in IκBα expression and phosphorylation, which indicated that SJW mediated the inhibition of NF-κB activation. In addition, SJW decreased the TNF-α-induced increase in the mRNA levels of pro-inflammatory adipokines, interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1). Collectively, our results indicate that SJW treatment could promote adipocyte differentiation probably through its anti-inflammatory activity, which in turn suggests that SJW has the potential to minimize the risk factors of metabolic syndrome.
authors.affiliation: School of Pharmaceutical Sciences, Mukogawa Women's University.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hatano
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sameshima
authors.forename: Mami
authors.initials: M
authors.lastname: Kawabata
authors.forename: Shizuo
authors.initials: S
authors.lastname: Yamada
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Shinozuka
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Nakabayashi
authors.forename: Hideya
authors.initials: H
authors.lastname: Mizuno
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D052242:Adiponectin / Q000096:biosynthesis; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology*; D015153:Blotting, Western; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D035264:Flowers / Q000737:chemistry; D020902:Hypericum / Q000737:chemistry*; D024821:Metabolic Syndrome / Q000517:prevention & control; D051379:Mice; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D047495:PPAR gamma / Q000096:biosynthesis; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D052242:Adiponectin; D000893:Anti-Inflammatory Agents; D016328:NF-kappa B; D047495:PPAR gamma; D010936:Plant Extracts