Hydroxyproline assay
Hydroxyproline (HYP) content was detected in murine lung tissues using an HYP measurement kit (NBP2-59747, Novus Biologicals, Littleton, CO, USA) following the instructions provided by the manufacturer. Approximately 30 mg of the diaphragmatic lobe of the right lung in each mouse was applied to conduct this examination. The ultimate content analysis was determined by the absorbance at 560 nm according to the standard curve.