Modulation of musculoskeletal hyperalgesia by brown adipose tissue activity in mice

Pain. 2016 Nov;157(11):2561-2570. doi: 10.1097/j.pain.0000000000000677.

Abstract

Cold exposure and a variety of types of mild stress increase pain in patients with painful disorders such as fibromyalgia syndrome. Acutely, stress induces thermogenesis by increasing sympathetic activation of beta-3 (β3) adrenergic receptors in brown adipose tissue. Chronic stress leads to the hypertrophy of brown adipose, a phenomenon termed adaptive thermogenesis. Based on the innervation of skeletal muscle by collaterals of nerves projecting to brown adipose, we theorized an association between brown adipose tissue activity and musculoskeletal hyperalgesia and tested this hypothesis in mice. Exposure to a cold swim or injection of BRL37344 (β3 adrenergic agonist) each enhanced musculoskeletal hyperalgesia, as indicated by morphine-sensitive decreases in grip force responses, whereas SR59230A (β3 adrenergic antagonist) attenuated swim-induced hyperalgesia. Chemical ablation of interscapular brown adipose, using Rose Bengal, attenuated the development of hyperalgesia in response to either swim stress or BRL37344. In addition, elimination of the gene expressing uncoupling protein-1 (UCP1), the enzyme responsible for thermogenesis, prevented musculoskeletal hyperalgesia in response to either a swim or BRL37344, as documented in UCP1-knockout (UCP1-KO) mice compared with wild-type controls. Together, these data provide a convergence of evidence suggesting that activation of brown adipose contributes to stress-induced musculoskeletal hyperalgesia.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue, Brown / drug effects
  • Adipose Tissue, Brown / pathology*
  • Adrenergic beta-Agonists / toxicity
  • Animals
  • Body Temperature / drug effects
  • Body Temperature / genetics
  • Body Weight / drug effects
  • Body Weight / genetics
  • Cold Temperature / adverse effects
  • Disease Models, Animal
  • Ethanolamines / toxicity
  • Female
  • Hyperalgesia / etiology*
  • Hyperalgesia / genetics
  • Hyperalgesia / pathology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Muscle Strength / drug effects
  • Musculoskeletal Pain / complications*
  • Musculoskeletal Pain / pathology
  • Musculoskeletal Pain / surgery
  • Pain Threshold / drug effects
  • Pain Threshold / physiology
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Swimming / psychology
  • Tail / innervation
  • Uncoupling Protein 1 / deficiency
  • Uncoupling Protein 1 / genetics

Substances

  • Adrenergic beta-Agonists
  • Ethanolamines
  • Ucp1 protein, mouse
  • Uncoupling Protein 1
  • BRL 37344