Targeting spinal mechanistic target of rapamycin complex 2 alleviates inflammatory and neuropathic pain.

ABSTRACT

The development and maintenance of chronic pain involves the reorganization of spinal nociceptive circuits. The mechanistic target of rapamycin complex 2 (mTORC2), a central signaling hub that modulates both actin-dependent structural changes and mTORC1-dependent mRNA translation, plays key roles in hippocampal synaptic plasticity and memory formation. However, its function in spinal plasticity and chronic pain is poorly understood. Here we show that pharmacological activation of spinal mTORC2 induces pain hypersensitivity, whereas its inhibition, using downregulation of the mTORC2-defining component Rictor, alleviates both inflammatory and neuropathic pain. Cell-type-specific deletion of Rictor showed that the selective inhibition of mTORC2 in a subset of excitatory neurons impairs spinal synaptic potentiation and alleviates inflammation-induced mechanical and thermal hypersensitivity, and nerve injury-induced heat hyperalgesia. The ablation of mTORC2 in inhibitory interneurons strongly alleviated nerve injury-induced mechanical hypersensitivity. Our findings reveal the role of mTORC2 in chronic pain and highlight its cell-type-specific functions in mediating pain hypersensitivity in response to peripheral inflammation and nerve injury.