title: Ginsenoside Rd alleviates mouse acute renal ischemia/reperfusion injury by modulating macrophage phenotype.
abstract: BACKGROUND
  Ginsenoside Rd (GSRd), a main component of the root of Panax ginseng, exhibits anti-inflammation functions and decreases infarct size in many injuries and ischemia diseases such as focal cerebral ischemia. M1 Macrophages are regarded as one of the key inflammatory cells having functions for disease progression.
  
  
  METHODS
  To investigate the effect of GSRd on renal ischemia/reperfusion injury (IRI) and macrophage functional status, and their regulatory role on mouse polarized macrophages in vitro, GSRd (10-100 mg/kg) and vehicle were applied to mice 30 min before renal IRI modeling. Renal functions were reflected by blood serum creatinine and blood urea nitrogen level and histopathological examination. M1 polarized macrophages infiltration was identified by flow cytometry analysis and immunofluorescence staining with CD11b(+), iNOS(+)/interleukin-12/tumor necrosis factor-α labeling. For the in vitro study, GSRd (10-100 μg/mL) and vehicle were added in the culture medium of M1 macrophages to assess their regulatory function on polarization phenotype.
  
  
  RESULTS
  In vivo data showed a protective role of GSRd at 50 mg/kg on Day 3. Serum level of serum creatinine and blood urea nitrogen significantly dropped compared with other groups. Reduced renal tissue damage and M1 macrophage infiltration showed on hematoxylin-eosin staining and flow cytometry and immunofluorescence staining confirmed this improvement. With GSRd administration, in vitro cultured M1 macrophages secreted less inflammatory cytokines such as interleukin-12 and tumor necrosis factor-α. Furthermore, macrophage polarization-related pancake-like morphology gradually changed along with increasing concentration of GSRd in the medium.
  
  
  CONCLUSIONS
  These findings demonstrate that GSRd possess a protective function against renal ischemia/reperfusion injury via downregulating M1 macrophage polarization.
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Kaixi
authors.initials: K
authors.lastname: Ren
authors.affiliation: Department of General Surgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Jin
authors.affiliation: Department of General Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Ma
authors.affiliation: Department of Traditional Chinese Medicine, Tangdu Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Qinyou
authors.initials: Q
authors.lastname: Ren
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Zhansheng
authors.initials: Z
authors.lastname: Jia
authors.affiliation: Department of Infectious Diseases, Tangdu Hospital, The Fourth Military Medical University, Xi'an, China.
authors.forename: Daocheng
authors.initials: D
authors.lastname: Zhu
keywords: ginsenoside Rd; macrophage; renal ischemia/reperfusion injury