title: Saikosaponin a, an active compound of Radix Bupleuri, attenuates inflammation in hypertrophied 3T3-L1 adipocytes via ERK/NF-κB signaling pathways.
abstract: Bupleurum falcatum L. is employed in oriental medicine in Korea. This root has been used for anti-inflammatory, anti-pyretic, and anti-hepatotoxic effects in the treatments of common cold, fever, and hepatitis. One of major bioactive compounds of Radix Bupleuri is the saikosaponin a (SSNa). However, little is known concerning the effects of SSNa on obesity associated with a state of low-grade inflammation. Consequently, this study was conducted to determine the inhibition of the inflammation pathway of SSNa in obesity. MTT assay was conducted for cytotoxicity and viability; nuclear and cytoplasmic fractions were extracted from adipocytes for translocation of nuclear factor-κB cells (NF-κB); nitric oxide (NO) production and secretion using Griess reagent; reverse transcription-polymerase chain reaction (RT-PCR) and immunoblotting for mRNA and protein levels associated with inflammation in the hypertrophied adipocytes. The results revealed that SSNa significantly decreased the expression of tumor necrosis factor-α (TNFα), interleukin (IL)-1β and IL-6 as proinflammatory cytokines, compared to that of non-treated control cells. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as inflammatory factors were reduced by treatment of these cells with SSNa and also suppressed NO production. Phosphorylation of IκBα was inhibited and translocation of NF-κB was suppressed via the ERK pathway in response to SSNa treatment. In conclusion, the results demonstrated that SSNa can inhibit the expression of inflammatory-associated genes in hypertrophied 3T3-L1 adipocytes and is a potent inhibitor of NF-κB activation. Thus these results suggest that SSNa is a novel therapeutic agent against that can be used against obesity-associated inflammation.
authors: Department of Herbal Pharmacology, College of Oriental Medicine, Daegu Haany University, Suseong‑gu, Daegu 706‑828, Republic of Korea.
authors: Sung Ok
authors: SO
authors: Kim
authors: Department of Herbal Pharmacology, College of Oriental Medicine, Daegu Haany University, Suseong‑gu, Daegu 706‑828, Republic of Korea.
authors: Ji Yeoung
authors: JY
authors: Park
authors: Department of Herbal Pharmacology, College of Oriental Medicine, Daegu Haany University, Suseong‑gu, Daegu 706‑828, Republic of Korea.
authors: Seo Young
authors: SY
authors: Jeon
authors: Department of Physiology, College of Oriental Medicine, Daegu Haany University, Suseong‑gu, Daegu 706‑828, Republic of Korea.
authors: Chea Ha
authors: CH
authors: Yang
authors: Department of Herbal Pharmacology, College of Oriental Medicine, Daegu Haany University, Suseong‑gu, Daegu 706‑828, Republic of Korea.
authors: Mi Ryeo
authors: MR
authors: Kim
mesh_terms: D041721:3T3-L1 Cells; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D007249:Inflammation / Q000235:genetics / Q000378:metabolism*; D018836:Inflammation Mediators / Q000378:metabolism; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D012503:Saponins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D018836:Inflammation Mediators; D016328:NF-kappa B; D012503:Saponins; D009569:Nitric Oxide; D009828:Oleanolic Acid; D048049:Extracellular Signal-Regulated MAP Kinases; C025759:saikosaponin D