Previous studies have shown that baicalin prevented iron accumulation after substantia nigra injury, reduced divalent metal transporter 1 expression, and increased ferroportin 1 expression in the substantia nigra of rotenone-induced Parkinson’s disease rats. In the current study, we investigated the relationship between iron accumulation and transferrin expression in C6 cells, to explore the mechanisms of the inhibitory effect of baicalin on iron accumulation observed in Parkinson’s disease rats. Iron content was detected using inductively coupled plasma-atomic emission spectroscopy. Results showed that iron content decreased 41%after blocking divalent metal transporter 1 and ferroportin 1 proteins. After treatment with ferric ammonium citrate of differing concentrations (10, 50, 100, 400 μg/mL) in C6 glioma cells, cell survival rate and ferroportin 1 expression were negatively correlated with ferric ammonium citrate concentration, but divalent metal transporter 1 expression positively correlated with ferric ammonium citrate concentration. Baicalin or deferoxamine reduced divalent metal transporter 1 expression, but increased ferroportin 1 expression in the 100 μg/mL ferric ammonium citrate-loaded C6 cells. These results indicate that baicalin down-regulated iron concentration, which positively regulat-ed divalent metal transporter 1 expression and negatively regulated ferroportin 1 expression, and decreased iron accumulation in the substantia nigra.

Baicalin, a type of flavonoid extracted from the dried root of Scutel aria baicalensis georgi, has been shown to effectively inhibit cellapoptosis. Therefore, we assumed that baicalin would suppress colistin sulfate-induced neuronal apoptosis. PC12 cells exposed to colistin sulfate (62.5-500 μg/mL) for 24 hours resulted in PC12 cellapoptosis. In addition, caspase-3 activity, lactate dehydrogenase level and free radical content increased in a dose-dependent manner. Subsequently, PC12 cells were pretreated with baicalin (25, 50 and 100 μg/mL), and exposed to 125 μg/mL colistin sulfate. cellmorphology markedly changed, and cellviability increased. Moreover, caspase-3 activity, lac-tate dehydrogenase level and free radical content decreased. Results indicated that baicalin inhib-ited colistin sulfate-induced PC12 cellapoptosis by suppressing free radical injury, and reducing caspase-3 activity and lactate dehydrogenase activity.