title: The screening and isolation of an effective anti-endotoxin monomer from Radix Paeoniae Rubra using affinity biosensor technology.
abstract: Lipopolysaccharide (LPS) is a known trigger in the pathogenesis of sepsis, lipid A being the toxic component. One of several adjuvant therapeutic approaches for severe sepsis is currently focusing on the neutralization of LPS. In order to obtain the components from traditional Chinese herbs that can neutralize the endotoxin, aqueous extractions were tested using affinity biosensor technology. From amongst 42 herbs, eight were found to possess lipid A-binding abilities. Radix Paeoniae Rubras had the highest lipid A-binding ability; therefore an aqueous extraction from this plant was investigated further. After preparation using standard methods, including silica gel chromatography and HPLC, we obtained 1, 2, 3, 4, 6-beta-d-pentagalloylglucose (PGG), with lipid A-binding ability. It was found that in vitro, PGG directly bound to lipid A, with a Kd of 32 microM, and that it neutralized the endotoxin both in the Limulus Amebocyte Lysate (LAL) assay and in a TNF-alpha release experiment, in a dose-dependent manner. In in vivo experiments, PGG was found to protect mice from a lethal challenge by LPS, and significantly decreased the plasma endotoxin level both in endotoxemic mice and rats, the reduction of the endotoxin level in rats being tightly associated with the TNF-alpha level. In conclusion, we demonstrate the effectiveness of affinity biosensor technology in discovering useful agents amongst traditional Chinese herbs and using this approach we found a new anti-endotoxin agent.
authors.affiliation: Medical Research Center, Southwestern Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Lv
authors.initials: L
authors.lastname: Genfa
authors.forename: Zheng
authors.initials: Z
authors.lastname: Jiang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Hong
authors.forename: Zheng
authors.initials: Z
authors.lastname: Yimin
authors.forename: Wang
authors.initials: W
authors.lastname: Liangxi
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Huang
authors.initials: H
authors.lastname: Ming
authors.forename: Jiang
authors.initials: J
authors.lastname: Donglen
authors.forename: Wei
authors.initials: W
authors.lastname: Lizhao
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000097:blood / Q000378:metabolism; D004353:Drug Evaluation, Preclinical; D004731:Endotoxins / Q000037:antagonists & inhibitors* / Q000097:blood; D006801:Humans; D007202:Indicators and Reagents; D008033:Limulus Test; D008050:Lipid A / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000187:drug effects; D029596:Paeonia / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D013329:Structure-Activity Relationship; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D016207:Cytokines; D004731:Endotoxins; D007202:Indicators and Reagents; D008050:Lipid A; D014409:Tumor Necrosis Factor-alpha