title: Identification of anti-inflammatory fractions of Geranium wilfordii using tumor necrosis factor-alpha as a drug target on Herbochip® - an array-based high throughput screening platform.
abstract: BACKGROUND
  Geranium wilfordii is one of the major species used as Herba Geranii (lao-guan-cao) in China, it is commonly used solely or in polyherbal formulations for treatment of joint pain resulted from rheumatoid arthritis (RA) and gout. This herb is used to validate a target-based drug screening platform called Herbochip® and evaluate anti-inflammatory effects of Geranium wilfordii ethanolic extract (GWE) using tumor necrosis factor-alpha (TNF-α) as a drug target together with subsequent in vitro and in vivo assays.
  
  
  METHODS
  A microarray-based drug screening platform was constructed by arraying HPLC fractions of herbal extracts onto a surface-activated polystyrene slide (Herbochip®). Using TNF-α as a molecular probe, fractions of 82 selected herbal extracts, including GWE, were then screened to identify plant extracts containing TNF-α-binding agents. Cytotoxicity of GWE and modulatory effects of GWE on TNF-α expression were evaluated by cell-based assays using TNF-α sensitive murine fibrosarcoma L929 cells as an in vitro model.
  
  
  RESULTS
  The in vivo anti-inflammatory effects of GWE were further assessed by animal models including carrageenan-induced hind paw edema in rats and xylene-induced ear edema in mice, in comparison with aspirin. The hybridization data obtained by Herbochip® analysis showed unambiguous signals which confirmed TNF-α binding activity in 46 herbal extracts including GWE. In L929 cells GWE showed significant inhibitory effect on TNF-α expression with negligible cytotoxicity. GWE also significantly inhibited formation of carrageenan-induced hind paw edema and xylene-induced ear edema in animal models, indicating that it indeed possessed anti-inflammatory activity.
  
  
  CONCLUSIONS
  We have thus validated effectiveness of the Herbochip® drug screening platform using TNF-α as a molecular target. Subsequent experiments on GWE lead us to conclude that the anti-RA activity of GWE can be attributed to inhibitory effect of GWE on the key inflammatory factor, TNF-α. Our results contribute towards validation of the traditional use of GWE in the treatment of RA and other inflammatory joint disorders.
authors.affiliation: Yunnan Baiyao-Herbcopoeia Laboratory Inc, 51 Xi-Ba Road, Kunming, Yunnan, China. apirl19810411@aliyun.com.|Yunnan Institute of Microbiology, Yunnan University, Kunming, China. apirl19810411@aliyun.com.
authors.forename: Min
authors.initials: M
authors.lastname: Huang
authors.affiliation: Institute of Biotechnology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan. her159@msn.com.
authors.forename: Pei-Wun
authors.initials: PW
authors.lastname: Yao
authors.affiliation: Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan. dtchang@life.nthu.edu.tw.
authors.forename: Margaret Dah-Tysr
authors.initials: MD
authors.lastname: Chang
authors.affiliation: Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan. s100080821@m100.nthu.edu.tw.
authors.forename: Sim-Kun
authors.initials: SK
authors.lastname: Ng
authors.affiliation: Institute of Biotechnology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan. yujaniwily0718@gmail.com.
authors.forename: Chien-Hui
authors.initials: CH
authors.lastname: Yu
authors.affiliation: School of Life Sciences, Yunnan Normal University, Kunming, Yunnan, China. zhyunfeng001@aliyun.com.
authors.forename: Yun-Feng
authors.initials: YF
authors.lastname: Zhang
authors.affiliation: Yunnan Institute of Microbiology, Yunnan University, Kunming, China. mlwen@ynu.edu.cn.
authors.forename: Meng-Liang
authors.initials: ML
authors.lastname: Wen
authors.affiliation: Yunnan Baiyao-Herbcopoeia Laboratory Inc, 51 Xi-Ba Road, Kunming, Yunnan, China. yangxiaoyuan@vip.sina.com.
authors.forename: Xiao-Yuan
authors.initials: XY
authors.lastname: Yang
authors.affiliation: Yunnan Baiyao-Herbcopoeia Laboratory Inc, 51 Xi-Ba Road, Kunming, Yunnan, China. yklai@life.nthu.edu.tw.|Institute of Biotechnology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan. yklai@life.nthu.edu.tw.
authors.forename: Yiu-Kay
authors.initials: YK
authors.lastname: Lai
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000032:analysis / Q000494:pharmacology / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000378:metabolism; D002351:Carrageenan / Q000627:therapeutic use; D002460:Cell Line; D002681:China; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D004487:Edema / Q000188:drug therapy / Q000378:metabolism; D031315:Geranium / Q000737:chemistry*; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008813:Mice, Inbred ICR; D046228:Microarray Analysis / Q000379:methods; D008517:Phytotherapy; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014992:Xylenes
chemical_list: D000893:Anti-Inflammatory Agents; D004365:Drugs, Chinese Herbal; D014409:Tumor Necrosis Factor-alpha; D014992:Xylenes; D002351:Carrageenan