Liver X Receptors Protect Dorsal Root Ganglia from Obesity-Induced Endoplasmic Reticulum Stress and Mechanical Allodynia

Abstract

Obesity is associated with many complications, including type 2 diabetes and painful neuropathy. There is no cure or prevention for obesity-induced pain, and the neurobiology underlying the onset of the disease is still obscure. In this study, we observe that western diet (WD)-fed mice developed early allodynia with an increase of ER stress markers in the sensory neurons of the dorsal root ganglia (DRG). Using cell-specific approaches, we demonstrate that neuronal liver X receptor (LXR) activation delays ER stress and allodynia in WD-fed mice. Our findings suggest that lipid-binding nuclear receptors expressed in the sensory neurons of the DRG play a role in the onset of obesity-induced hypersensitivity. The LXR and lipid-sensor pathways represent a research avenue to identify targets to prevent debilitating complications affecting the peripheral nerve system in obesity.

Keywords: DRG; ER stress; diet-induced obesity; liver X receptors; neuropathy.