Total RNA was extracted as described previously with minor modification [12 (link)]. In brief, untreated seminal plasma after thawing was immediately confused with Trizol LS (Invitrogen, Carlsbad, USA) at a higher concentration (0.2ml untreated seminal plasma with 0.8ml Trizol LS) to ensure enough quantity for consequent miRNA cDNA synthesis. All procedures were followed according to the manufacturer's instruction.
The purity of total RNA was checked using an ultraviolet spectrophotometer (Biometra, Göttingen, Germany) at 260 nm and 280 nm, and the RNA concentration was calculated using the OD260.
The purity of total RNA was checked using an ultraviolet spectrophotometer (Biometra, Göttingen, Germany) at 260 nm and 280 nm, and the RNA concentration was calculated using the OD260.