DHCR24 and hyperinsulinemic hypoglycemia, familial, 4: In our study, in hippocampal HT22 neuronal cell models of cellular cholesterol deficiency induced by DHCR24 knockdown, we found that deficiency of cellular cholesterol obviously increased intracellular and extracellular Aβ40/42 generation, conversely, in hippocampal HT22 neuronal cell models of increased cellular cholesterol level mediated by DHCR24 knockin, elevated cellular cholesterol markedly reduced the production of intracellular and extracellular Aβ40/42 (Fig. 2).