Total Western Diet Alters Mechanical and Thermal Sensitivity and Prolongs Hypersensitivity Following Complete Freund's Adjuvant in Mice

Abstract

Obesity and chronic pain are often comorbid and their rates are rising. It is currently unknown whether increased pain is due to greater weight or poor diet quality, or both. Therefore, we utilized a Total Western Diet (TWD) to investigate the functional and physiological consequences of nutritionally-poor diet in mice. During thirteen weeks on the commercially-available TWD, based on the National Health and Nutrition Examination Survey (NHANES), thresholds of TWD-fed mice significantly increased in both thermal and mechanical tests. Quantitative magnetic resonance (QMR) imaging revealed a significant increase in fat mass with a concomitant decrease in lean mass, in the TWD-fed mice. Additionally, there were significant increases in serum leptin and inflammatory cytokines. Following chronic pain induction using Complete Freund’s Adjuvant (CFA), hypersensitivity was more pronounced and significantly prolonged in the TWD-fed mice. Therefore, prolonged exposure to poor diet quality resulted in altered acute nociceptive sensitivity, systemic inflammation and persistent pain following inflammatory pain induction.

Evaluating analgesic efficacy and administration route following craniotomy in mice using the grimace scale

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High-fat diet increases pain behaviors in rats with or without obesity

“…Some preclinical studies show that diet-induced obesity increases arthritis severity in animal models, although most of these did not directly measure pain responses 23 – 26 . Enhanced pain responses in peripheral inflammation models in rodents with diet-induced obesity have been shown in a few studies 27 – 29 . However, to our knowledge there are no preclinical studies of obesity in radicular pain models.…”

Pain pathogenesis in rheumatoid arthritis—what have we learned from animal models?

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