Navigation
High-fat diet causes mechanical allodynia in the absence of injury or diabetic pathology
It is postulated that high-fat diets (HFD) cause an increase in pain sensitivity, neuropathic pain, and hyperresponsiveness to stimuli that would not normally illicit pain, a condition known as allodynia. This is particularly important in the western dietary pattern (WD), which has elevated levels of fats and generates a myriad of systemic bioactive metabolites. Improving our understanding of the relationship between obesity, diet, and diabetes is paramount to the understanding of diabetic neuropathy. To that end, Tierney et al. (2022) used a mouse model to observe the impact of a HFD on increasing pain sensitivity. After exposing the mice to the HFD for 8 weeks the authors noted the following observations: firstly, HFD mice were found to be increasingly sensitive to intraplantar prostaglandin E2 (PGE2) compared to controls (mechanical allodynia). In addition, the intake of a HFD was linked to elevated levels of ATF3 in the lumbar dorsal root ganglia (DRG), indicating neuronal injury. Finally, a HFD led to an alteration in neuron composition at nerve endings, where HFD mice were found to have a higher percentage of capsaicin-responsive neurons than control mice via calcium imaging. Collectively, these findings lead the authors to postulate that a HFD causes allodynia through consequential bioactive metabolites, irrespective of previous pathology or injury. The authors present these findings in hopes to improve the understanding of the relationship between diabetes and obesity to help create effective pharmacological interventions. [NPID: Immunology, feeding behavior, neuroscience, neuroimmunology, high fat diet, pain sensitivity, allodynia, mice]
Year: 2022
