title: Gu-Ben-Fang-Xiao decoction attenuates sustained airway inflammation by suppressing ER stress response in a murine asthma remission model of respiratory syncytial virus infection.
abstract: BACKGROUND
  In recent years, asthma has increased dramatically in prevalence with a considerable economic burden all over the world. Long-term remission should be regarded as the promising and meaningful therapeutic goal in asthma management. However, the precise definition criteria and rational therapies for asthma remission have not been well-established. In academia, there is a consensus that even in those who develop asymptomatic remission of asthma, persistent airway inflammation is ubiquitous. Gubenfangxiao decoction (GBFXD) has been widely used in treating asthma remission stage for decades in the Jiangsu Province Hospital of Chinese Medicine, China. We previously demonstrated that GBFXD could downregulate the asthma susceptibility gene ORMDL3, a trigger of Endoplasmic reticulum (ER) stress and unfolded protein response (UPR).
  To investigate the involvement of ER stress and UPR in the anti-inflammatory effects of GBFXD in Respiratory Syncytial Virus (RSV)-OVA-induced asthma remission mice.
  
  
  METHODS
  Mice were orally administered GBFXD at three doses for 30 days after an RSV-OVA challenge. The levels of inflammation mediators in serum were measured using a Luminex assay and the amount of IFN-γ in lung homogenates was detected using ELISA. The splenic CD4+ and CD8+ T lymphocytes were counted using flow cytometric analysis. The mRNA and protein levels of asthma susceptibility gene ORMDL3, ER stress markers (BIP, CHOP), and three canonical UPR branches (PERK-eIF2a-ATF4, IRE1α-XBP1/IRE1α-JNK-AP1 and ATF6-SERCA2b signal pathways) were detected using real-time RT-PCR and western blot.
  
  
  RESULTS
  Histopathological analysis showed that the model group mice still exhibited a sustained airway inflammation even after suspending the OVA-challenge and RSV infections for 30 days. H&E staining results indicated that GBFXD could attenuate sustained airway inflammation. Decreased serum CXCL1 level and increased IFN-γ level in lung homogenate were observed after GBFXD treatment. Reductions in the number of splenic CD4+/CD8+ T lymphocytes were found after DEX treatment. We further confirmed the previous finding that GBFXD could downregulate the expression of ORMDL3. As a result of suppressed UPR, decreased ER stress markers and inhibited UPR branches (PERK and IRE1α signal pathway) were also observed through the significant reduction of signature mRNA and protein expressions after GBFXD treatment.
  
  
  CONCLUSIONS
  GBFXD can significantly attenuate RSV-OVA-induced persistent airway inflammation in murine asthma remission model. These effects may be mediated, at least partially, by inhibiting the activation of ER stress responses.
authors.affiliation: Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China. Electronic address: heiheidoctor@163.com.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China. Electronic address: 710735592@qq.com.
authors.forename: Jian-Ya
authors.initials: JY
authors.lastname: Xu
authors.affiliation: Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China. Electronic address: 2461969297@qq.com.
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Zhang
authors.affiliation: Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China. Electronic address: zhaoxiahy@126.com.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000818:Animals; D018927:Anti-Asthmatic Agents / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001249:Asthma / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects*; D005260:Female; D005786:Gene Expression Regulation; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018836:Inflammation Mediators / Q000097:blood; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology / Q000821:virology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008807:Mice, Inbred BALB C; D010047:Ovalbumin; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012074:Remission Induction; D018357:Respiratory Syncytial Virus Infections / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology / Q000821:virology; D015398:Signal Transduction / Q000187:drug effects; D013154:Spleen / Q000187:drug effects / Q000378:metabolism; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism; D056811:Unfolded Protein Response / Q000187:drug effects
chemical_list: D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D016207:Cytokines; C497250:Ddit3 protein, mouse; D004365:Drugs, Chinese Herbal; D000091342:Endoplasmic Reticulum Chaperone BiP; C000617791:Gu-Ben-Fang-Xiao decoction; D006360:Heat-Shock Proteins; D018836:Inflammation Mediators; D008565:Membrane Proteins; C583840:ORMDL3 protein, mouse; D012333:RNA, Messenger; D051742:Transcription Factor CHOP; D010047:Ovalbumin
keywords: Asthma remission; ER stress; GuBenFangXiao decoction; Hesperidin (PubChem CID, 10621, CAS# 520-26-3); Liquiritin (PubChem CID, 503737, CAS# 551-15-5); Lobetyolin (PubChem CID, 6369123, CAS# 136085-37-5); Magnolin (PubChem CID, 169234, CAS# 31008-18-1); Prim-o-glucosylcimifugin (PubChem CID, 14034912, CAS# 80681-45-4); Schisandrol A (PubChem CID, 23915, CAS# 7432-28-2); Sustained airway inflammation; Unfolded protein response