title: Rg3 Improves Mitochondrial Function and the Expression of Key Genes Involved in Mitochondrial Biogenesis in C2C12 Myotubes.
abstract: BACKGROUND
  Panax ginseng has glucose-lowering effects, some of which are associated with the improvement in insulin resistance in skeletal muscle. Because mitochondria play a pivotal role in the insulin resistance of skeletal muscle, we investigated the effects of the ginsenoside Rg3, one of the active components of P. ginseng, on mitochondrial function and biogenesis in C2C12 myotubes.
  
  
  METHODS
  C2C12 myotubes were treated with Rg3 for 24 hours. Insulin signaling pathway proteins were examined by Western blot. Cellular adenosine triphosphate (ATP) levels and the oxygen consumption rate were measured. The protein or mRNA levels of mitochondrial complexes were evaluated by Western blot and quantitative reverse transcription polymerase chain reaction analysis.
  
  
  RESULTS
  Rg3 treatment to C2C12 cells activated the insulin signaling pathway proteins, insulin receptor substrate-1 and Akt. Rg3 increased ATP production and the oxygen consumption rate, suggesting improved mitochondrial function. Rg3 increased the expression of peroxisome proliferator-activated receptor γ coactivator 1α, nuclear respiratory factor 1, and mitochondrial transcription factor, which are transcription factors related to mitochondrial biogenesis. Subsequent increased expression of mitochondrial complex IV and V was also observed.
  
  
  CONCLUSIONS
  Our results suggest that Rg3 improves mitochondrial function and the expression of key genes involved in mitochondrial biogenesis, leading to an improvement in insulin resistance in skeletal muscle. Rg3 may have the potential to be developed as an anti-hyperglycemic agent.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.|Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, Korea.
authors.forename: Min Joo
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Korea.
authors.forename: Young Do
authors.initials: YD
authors.lastname: Koo
authors.affiliation: Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, Korea.
authors.forename: Min
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Soo
authors.initials: S
authors.lastname: Lim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.|Biomedical Research Institute and Innovative Research Institute for Cell Therapy, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sung Soo
authors.initials: SS
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea.
authors.forename: Hak C
authors.initials: HC
authors.lastname: Jang
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea. kspark@snu.ac.kr.
authors.forename: Kyong Soo
authors.identifier: http://orcid.org/0000-0003-3597-342X
authors.initials: KS
authors.lastname: Park
keywords: Ginsenoside Rg3; Mitochondria; Panax