Protective Effect Of Autophagy On Alcohol-induced PC12Cell Injury

Autophagy is a phenomenon of life which is widely present in eukaryotic cells, it isa lysosomal pathway for degradation of cytoplasmic organelles and long-lived proteins ineukaryotic cells. It is a highly conserved mechanism during the degradation of largemolecules, ribosomes and organelle. Autophagy is generally considered to temporarilyprovide chance of survival for cells in some circumstances, such as absence of amino acidsand nutrients, hypoxia and metabolic stress. Programmed cell death is a type of cell deathwhich is different from necrosis cell death, it is divided into apoptotic cell death andautophagic cell death. Studies have shown that autophagy, as a type of programmed cell death,may be brought cells to the final death in some cases, such as apoptosis-blocked. Alcohol is aneurotropic substances, which can induce injury in many body’s systems and organs. Nervoussystem is one of the main target organ of these injuries. Neurotoxic effects of alcohol mainlymanifest in oxidative damage, change of the cell cytoplasm membrane, inducing cellapoptosis and other aspects. Domestic and international studies of alcohol-induced injury innerve cell is still uncommon in autophagic death aspect.Objective: The studies were designed to evaluate whether autophagy was inducedby alcohol in PC12cell, and whether autophagy plays a role in alcohol mediated cytotoxicityin PC12cell. The results may provide the experimental basis for the further study ofrevealing alcohol neurotoxicity, and also provide a theoretical basis for the recovery ofalcohol-induced injury in nerve cells. Methods: PC12cells were divided into the following four groups: control, alcoholtreated, autophagy inhibitor3-MA+alcohol treated, pancaspase inhibitor z-VAD-fmk+alcohol treated. To determine whether alcohol can induce autophagy in PC12cell, therecombinant expression vector pEGFP-LC3were constructed and transiently transfected intoPC12cells. The role of autophagy in the process of alcohol-inhibited proliferation of PC12cell was detected by MTT assay. To investigate the role of autophagy in alcohol-inducedoxidative injury of PC12cells, the level of reactive oxygen species was detected by highcontent screening(HCS). Immunofluorescence analysis, HCS, Western blot analysis wereused to investigate the relationship between autophagy and apoptosis in alcohol-inducedPC12cell injury.Results:(1) Autophagy is present in the process of alcohol-induced PC12cellinjury;(2) In the process of alcohol-induced PC12cell injury, inhibition of autophagy willlead to decrease of cell survival and rise of oxidative injury level of PC12cells;(3) In theprocess of alcohol-induced PC12cell injury, inhibition of autophagy will risecaspase-mediated apoptosis levels, inhibition of caspase-mediated apoptosis will riseautophagy levels.Conclusions:(1) Autophagy, as a protective effect to maintain the steady-statebalance of cells,is present in the process of alcohol-induced PC12cell injury;(2) In theprocess of alcohol-induced PC12cell injury, there is a relativity between autophagy andapoptosis. Inhibition of autophagy leads to risen levels of caspase-mediated apoptosis,inhibition of caspase-mediated apoptosis leads to risen levels of autophagy.