抄録
[Aims] Corpus luteum (CL) regression is required for subsequent estrus cycle in most mammals including cattle. This study aimed to evaluate the autophagic and lysosomal activities associated with apoptotic activity during bovine CL regression. [Material and Methods] Mid and late CL were collected from a local abattoir. Autophagic status was evaluated by measuring expression of autophagy-related genes (LC3α, LC3β, Atg3 and Atg7) by qRT-PCR and detecting LC3 protein by immunohistochemistry and western blotting. Next, activities of lysosome and cathepsin B were measured by commercial kits. Moreover expression of cathepsin-related genes (CTSB, CTSD, and CTSZ), that are members of lysosomal protease were performed in addition to cathepsin B protein was detected by immunohistochemistry. Apoptotic status was evaluated by measuring expression of CASP3 and detection of caspase 3 activity with commercial kit. [Results and Discussion] Expressions of LC3α, LC3β, Atg3 and Atg7 and the level of LC3 protein especially LC3II showed a significant increase in late CL than mid CL. Lysosomal activity showed a significant increase in late CL than mid CL. Moreover expressions of CTSB, CTSD, and CTSZ were significantly higher in late CL than those in mid CL. Furthermore higher level of activity and expression of cathepsin B protein were also observed in late CL than those in mid CL. A significantly higher CASP3 expression and higher activity of caspase 3 were observed in late CL than mid CL. These results suggest that autophagy and lysosomal activities have a role in bovine CL regression through expressions of autophagy-related genes and protein in relation to activities of lysosome and cathepsins.
