National Basic Research Program of China [2005CB522804]; National Science Foundation of China [31070741]Formaldehyde (FA) is widely present in the environment, and is also a mammalian metabolite. However, its biological role has not been well understood. Here, we show that FA plays an anti-apoptotic role in cultured hippocampal neurons: FA suppressed staurosporine-induced neuronal apoptosis and inhibited the activity of apoptosis-associated caspase-3/7 proteases in a concentration-dependent manner. Moreover, FA suppressed outward K+ currents and attenuated the enhanced I-K currents that are associated with neuronal apoptosis. As an increase in outward K+ currents is critical for cell apoptosis, our results suggest that FA exerts its anti-apoptotic effects on neuronal cells, probably through its inhibitory effect on the outward K+ currents
