Cyclin-dependent kinase 5 inhibitor attenuates lipopolysaccharide-induced neuroinflammation through metabolic reprogramming.

The atypical cyclin-dependent kinase 5 (CDK5) is considered a neuron-specific kinase that plays important roles in many cellular functions including neuronal migration, neuronal differentiation, synapse development, and synaptic functions. However, the role of CDK5 in microglia under physiological and pathological conditions remains unclear. This study showed that treatment with lipopolysaccharide (LPS) caused the release of pro-inflammatory mediators and increased expression of CDK5 in BV2 microglia in vitro. Moreover, lipopolysaccharide treatment-induced glycolysis by increasing the expression levels of HIF-1α, PFKFB3, and HK2. Application of CDK5 inhibitor roscovitine significantly decreased LPS-induced CDK5 expression and glycolysis, thus suppressing neuroinflammation in the cells. The roscovitine treatment of BV2 cells also significantly blocked the HIF-1 activator, CoCl-mediated HIF-1α, HK2, and PFKFB3 expression. Finally, we demonstrated that roscovitine inhibited microglial activation, metabolic reprogramming, expression of pro-inflammatory markers, cell apoptosis, and alleviated memory impairment in LPS-injected mice. In summary, our results suggest that inhibition of CDK5 can reduce the neuroinflammation of microglia through modulation of metabolic reprogramming.