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Analgesia induced by dietary restriction is mediated by the kappa-opioid system

Mercedes de los Santos-Arteaga1, Sergio A Sierra-Domínguez, German H Fontanella

  • 1División de Neurociencias, Universidad Pablo de Olavide de Sevilla, 41013 Sevilla, Spain.

The Journal of Neuroscience : the Official Journal of the Society for Neuroscience
|December 6, 2003
PubMed

Insights

Intermittent fasting reduces pain sensitivity in mice by enhancing the spinal cord's kappa-opioid system. This dietary approach may offer a novel strategy for pain management.

Area of Science:

  • Neuroscience
  • Pain Research
  • Metabolic Studies

Background:

  • Understanding nociceptive processing is key to advancing pain control.
  • Dietary interventions are increasingly explored for their systemic effects.

Purpose of the Study:

  • To investigate the impact of intermittent fasting on pain responses.
  • To elucidate the underlying mechanisms of diet-induced analgesia.

Main Methods:

  • Comparison of pain responses in mice on intermittent fasting diets versus ad libitum feeding.
  • Pharmacological and molecular analyses of the kappa-opioid system in the spinal cord.
  • Measurement of prodynorphin mRNA, kappa-opioid receptors, DREAM activity, and c-Fos expression.

Main Results:

  • Intermittent fasting significantly reduced thermal and visceral pain responses.
  • Increased spinal cord prodynorphin mRNA and kappa-opioid receptor levels were observed in fasting mice.
  • Reduced activity of the transcriptional repressor DREAM and lower c-Fos expression in the spinal cord indicated suppressed nociceptive signaling.

Conclusions:

  • Dietary restriction via intermittent fasting enhances the endogenous kappa-opioid system, leading to analgesia.
  • Dynorphin likely inhibits nociceptive information transmission at the spinal cord level.
  • Combined dietary restriction and kappa-opioid agonists present a potential therapeutic avenue for pain relief.

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