title: An aqueous extract of the popular Chinese nutraceutical Kwei Ling Ko (Tortoise shell-Rhizome jelly) activates the PPARgamma pathway and down-regulates the NFkappaB activity.
abstract: It is generally believed that the popular nutraceutical 'Kwei Ling Ko' (KLK; Tortoise shell-Rhizome jelly) has antiinflammatory effects, but the mechanism by which its effects are manifested remains unknown. Peroxisome proliferation-activated receptors (PPARs) are members of the nuclear hormone receptor/transcription factor superfamily with multiple roles in adipocyte differentiation, glucose homeostasis, immunomodulation and antiinflammatory regulation. As PPAR is required for adipocyte induction, we used adipogenesis as a possible screen for the activation of the PPAR pathway. Interestingly, an aqueous extract of KLK (sKLK) was able to induce the adipocyte differentiation of fibroblast cell lines. Adipogenesis was confirmed by flow cytometric analysis using a fluorescent lipid stain. Up-regulation of PPARgamma transcripts during adipogenesis was also demonstrated by reverse transcription-polymerase chain reaction (RT-PCR). The sKLK-induced adipogenesis was similar to that elicited by insulin. The activity of nuclear factor-kappaB (NFkappaB), a transcription factor responsible for the regulation of proinflammatory genes, was also down-regulated in response to sKLK. Luciferase reporter gene assays further demonstrated that sKLK inhibited both basal and tumor necrosis factor-alpha-stimulated NFkappaB activation. The activities reported in this study support an immunomodulatory effect for sKLK. As activation of PPAR pathway has a dual role in adipogenesis and anti-inflammation, our observations are consistent with the notion that KLK possesses antiinflammatory properties.
authors.affiliation: Department of Biochemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: E C H
authors.initials: EC
authors.lastname: Yip
authors.forename: A M F
authors.initials: AM
authors.lastname: Liu
authors.forename: J T Y
authors.initials: JT
authors.lastname: Wong
authors.forename: Y H
authors.initials: YH
authors.lastname: Wong
mesh_terms: D016475:3T3 Cells; D050156:Adipogenesis / Q000187:drug effects*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D015536:Down-Regulation; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D017930:Genes, Reporter / Q000187:drug effects; D006801:Humans; D051379:Mice; D016328:NF-kappa B / Q000187:drug effects; D047492:Peroxisome Proliferator-Activated Receptors / Q000187:drug effects*; D027343:Rhizome; D032281:Smilax; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014426:Turtles; D015854:Up-Regulation
chemical_list: D000893:Anti-Inflammatory Agents; D004365:Drugs, Chinese Herbal; D016328:NF-kappa B; D047492:Peroxisome Proliferator-Activated Receptors; D014409:Tumor Necrosis Factor-alpha