The Effects of Astragali Radix Extracts on Mitochondrial Function in C2C12 Myotubes

C2C12 골격근세포에서 황기의 미토콘드리아 조절 작용

Objective: The prevalence of metabolic syndrome and type 2 diabetes is increasing worldwide. Mitochondrial dysfunction is known to be involved in insulin resistance and obesity, researches have been increasing highly. Astragali Radix extract (ARE) or its main components have been shown to perform comparably to insulin by significantly reducing blood glucose levels in animal models however, the influence on mitochondrial dysfunction are not well understood. Methods: ARE (0.2, 0.5 and 1.0 mg/ml) or metformin (2.5 mM) were treated in C2C12 after 6 day-differentiation. The expressions of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and phosphorylation AMPK, peroxisome proliferators-activated receptror ${\gamma}$ coactivator $1{\alpha}$ ($PGC1{\alpha}$), nuclear respiratory factors 1 (NRF1), mitochondrial transcription factor (Tfam) and myosin heavy chain were detected with western blotting or polymerase chain reaction analysis. The morphological changes were also investigated. Results: ARE dose dependently increased phosphorylation of AMPK and respectively activated mRNA expressions of $PGC1{\alpha}$, NRF1 and Tfam which are mitochondrial biogenesis regulators. Furthermore, there were some morphologic differences of differentiated cells between ARE treatment and control. Conclusions: This study suggests that ARE has the potential to increase muscle mitochondrial function by activating AMPK and $PGC1{\alpha}$.