d-β-hydroxybutyrate inhibits the apoptosis of PC12 cells induced by 6-OHDA in relation to up-regulating the ratio of Bcl-2/Bax mRNA

d-β-hydroxybutyrate (DβHB) is a predominant member of ketone bodies produced by hepatocytes and, to a lesser extent, by astrocytes. It is an alternative source of energy in the brain when glucose supply is depleted such as during starvation. It has been reported that ketone bodies could protect dopaminergic culture. However, the biological function of DβHB in Parkinson disease (PD) is still unclear. In the present work, we investigated the role of DβHB in protecting rat pheochromocytoma (PC12) cells from apoptosis induced by 6-Hydroxydopamine (6-OHDA). DβHB rescued PC12 cells from apoptotic death induced by 6-OHDA by MTT assay, acridine orange (AO) staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining and the activity of caspase-3. DβHB prevented the decrease of cell viability and the increase of caspase-3 activity induced by 6-OHDA in a dose-dependent manner in PC12 cells. AO and TUNEL staining showed that DβHB prevented the apoptosis of PC12 cells induced by 6-OHDA. The ratio of Bcl-2/Bax at mRNA levels, which regulates the apoptosis of PC12 cells when exposed to 6-OHDA, increased when DβHB was preincubated. The data showed that DβHB inhibited the apoptosis of PC12 cells induced by 6-OHDA in relation to up-regulating the ratio of Bcl-2/Bax mRNA.