title: A dual-role of Gu-4 in suppressing HMGB1 secretion and blocking HMGB1 pro-inflammatory activity during inflammation.
abstract: BACKGROUND
  High mobility group box 1(HMGB1) was first recognized as a nuclear protein that increased the chromatin remodeling and regulates transcription of many genes. In recent years, HMGB1 has been identified as a critical "late" pro-inflammatory mediator due to its unique secretion pattern and lethal effects in sepsis. Therefore, preventing the active release and inhibiting the pro-inflammatory activity of HMGB1 become promising strategies for the treatment of sepsis. Here, we reported the therapeutic effects of Gu-4, a lactosyl derivative, on sepsis and the underlying molecular mechanisms.
  
  
  RESULTS
  In an experimental rat model of sepsis caused by cecal ligation and puncture (CLP), Gu-4 administration prominently attenuated lung injury and improved the survival of the septic animals, which was positively correlated with the decrease of the serum HMGB1 level. Using RAW264.7 macrophage cell line, we further showed that Gu-4 significantly suppressed the lipopolysaccharide (LPS)-induced release and cytoplasmic translocation of HMGB1. Moreover, Gu-4 not only dose-dependently attenuated recombinant human (rhHMGB1)-induced production of TNF-α, IL-6, and IL-1β in THP-1 cells, but also greatly inhibited the adhesion of rhHMGB1-challenged THP-1 cells to HUVECs. Analyses of flow cytometry demonstrated that Gu-4 could effectively reduce the activation of CD11b elicited by rhHMGB1. Western blot analyses revealed that Gu-4 treatment could partially block the rhHMGB1-induced activation of ERK and NF-κB signalings. Meanwhile, CD11b knockdown also obviously attenuated the rhHMGB1-induced phosphorylations of ERK and IKKα/β.
  
  
  CONCLUSIONS
  Taken together, our results suggest that Gu-4 possesses a therapeutic potential in the treatment of sepsis probably via inhibiting the LPS-induced release of HMGB1 from macrophages and via suppressing the pro-inflammatory activity of HMGB1.
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Huiting
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Ji
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Ju
authors.initials: J
authors.lastname: Xuan
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Zhilin
authors.initials: Z
authors.lastname: Qi
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Shen
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China; Collaborative Innovation Center of Biomedicine for Public Hygiene Emergency and Critical Care, Jiangsu Life Sciences & Technology Innovation Park, Nanjing, Jiangsu, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lan
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, PR China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China; Collaborative Innovation Center of Biomedicine for Public Hygiene Emergency and Critical Care, Jiangsu Life Sciences & Technology Innovation Park, Nanjing, Jiangsu, PR China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, PR China.
authors.forename: Zhongjun
authors.initials: Z
authors.lastname: Li
authors.affiliation: Jiangsu Province Key Laboratory for Molecular and Medicine Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu, PR China; Collaborative Innovation Center of Biomedicine for Public Hygiene Emergency and Critical Care, Jiangsu Life Sciences & Technology Innovation Park, Nanjing, Jiangsu, PR China.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D000818:Animals; D015153:Blotting, Western; D039481:CD11b Antigen / Q000235:genetics / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005973:Glutamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D024243:HMGB1 Protein / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects; D006801:Humans; D051550:I-kappa B Kinase / Q000378:metabolism; D007249:Inflammation / Q000378:metabolism*; D007785:Lactose / Q000031:analogs & derivatives* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D034622:RNA Interference; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D018805:Sepsis / Q000378:metabolism / Q000401:mortality / Q000517:prevention & control*; D015996:Survival Rate
chemical_list: D039481:CD11b Antigen; C540504:Gu-4 compound; D024243:HMGB1 Protein; D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D005973:Glutamine; D051550:I-kappa B Kinase; D048049:Extracellular Signal-Regulated MAP Kinases; D007785:Lactose