Reverse transcription (RT)-PCR was employed to analyse the differential gene
expression at a transcriptional level. Total RNA was extracted from the liver samples
of the four groups using TRIzol (Invitrogen, USA). Aliquots of the total RNA (5 μg)
were reverse-transcribed with Super Script III (Invitrogen) according to the manufacturer’s
instructions. PCR was performed with an iCycler Thermal Cycler (Bio-
Rad, USA). cDNA (0.5 μL) were used for each PCR amplification in a total reaction
volume of 15 μL, and all reactions were performed in duplicate. The ubiquitin C transcript
was adopted as an internal control. The amplification was initiated by 4 min
of denaturation at 94 °C for one cycle, followed by 30 cycles at 94 °C for 30 s, 58 °C
for 30 s, and 72 °C for 1 min. After the last cycle of amplification, samples were
incubated for 7 min at 72 °C. The PCR products were examined in 1% agarose gels
stained with SYPRO Safe (1:100000; Invitrogen) and analysed using Quantity One
software (Bio-Rad).