Comparisons of Ethanol Extracts of Chinese Propolis (Poplar Type) and Poplar Gums Based on the Antioxidant Activities and Molecular Mechanism

Figure 4

EECP and EEPG stimulated the mRNA expression of antioxidant genes in RAW264.7 cells. ((a)–(d)) To detect the time-course of EECP and EEPG on the mRNA expression of antioxidant genes, cells were treated with EECP (5 μg/mL) or EEPG (15 μg/mL) for indicated lengths of time. ((e)–(h)) RAW264.7 cells were treated with indicated concentrations of EECP and EEPG for 6 h. The expressions of mRNA were measured by qRT-PCR and the results were normalized by GAPDH, which were conducted for three independent experiments and the results were expressed as mean ± SD.

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