Detection of autophagic flux in primary cerebral cortical neurons after oxygen glucose deprivation/reperfusion (OGD/R) using various methods

The current research hot spot in the field of autophagic flux is to explain and alleviate disease from the perspective of autophagy. A highly sophisticated, sensitive, quantifiable and comprehensive method is required to accurately determine the dynamic process of autophagic flux. There are very few methods in neuroscience that specifically examine autophagic flux. Therefore, primary cortical neurons were divided into oxygen glucose deprivation/reperfusion (OGD/R) (group A) and OGD/R plus bafilomycin A1 (BafA1) (group B) groups. (1) Transfection of the LC3 gene with the RFP-GFP tandem fluorescent label was performed. (2) Direct quantification was performed using transmission electron microscopy (TEM). (3) Autophagy-related tools were used to detect the transformation of LC3I/II. (4) SQSTM1/P62 combined with the LC3 protein flip test was performed to comprehensively evaluate autophagic flux. Using method one, the ratio of autophagolysosomes to autophagosomes in group A was significantly increased based on fluorescence microscopy analysis. Using method two, the autophagy process in group A was more continuous and unobstructed based on TEM analysis, while only some partial processes were observed in group B, and the number of autophagosomes and autophagy lysosomes in group A was significantly greater more than that in group B. The LC3II/I ratio measured in method three was analysed in detail to explain the autophagic flux. The ratio of soluble p62 combined with the ratio of LC3II/I detected using method four reflected the activation of autophagy. In summary, each method has its own advantages, and different methods and indicators can be used to monitor different stages of autophagy. An understanding of these advantages and mastery of these methods, is a very promising strategy to systematically and objectively study central nervous system diseases, facilitate the rational use of drugs, and formulate effective treatment plans from the perspective of autophagy.