About TRPV1 receptors...
Involvement of TRPV1 and the efficacy of α-spinasterol on experimental fibromyalgia symptoms in mice
Author links open overlay panel
Susana Paula MoreiraFischeraIndiaraBruscoaEvelyne SilvaBrumaMaria Fernanda PessanoFialhoaCamilaCamponogaraaRahisaScusselbRicardo AndrezMachado-de-ÁvilabGabrielaTrevisancSara MarchesanOliveiraa
Show more
https://doi.org/10.1016/j.neuint.2020.104673Get rights and content
Highlights
•
Reserpine caused nociceptive/depressive-like behaviours without promoting physical alterations.
•
TRPV1 is involved in the reserpine-induced nociceptive/depressive-like behaviours.
•
α-spinasterol, a new TRPV1 antagonist, decreased reserpine-induced nociception-depression.
Abstract
Fibromyalgia is characterised mainly by symptoms of chronic widespread pain and comorbidities like depression.
Although these symptoms cause a notable impact on the patient's quality of life, the underlying aetiology and pathophysiology of this disease remain incompletely elucidated.
The transient receptor potential vanilloid type 1 (TRPV1) is a polymodal receptor that is involved in the development of nociceptive and depressive behaviours, while α-spinasterol, a multitarget TRPV1 antagonist and cyclooxygenase inhibitor, presents antinociceptive and antidepressant effects.
The present study investigated the involvement of the TRPV1 channel and the possible effects of α-spinasterol on nociceptive and depressive-like behaviours in an experimental fibromyalgia model.
The fibromyalgia model was induced with a subcutaneous (s.c.) injection of reserpine (1 mg/kg) once daily for 3 consecutive days in male Swiss mice.
Reserpine administration depleted monoamines and caused mechanical allodynia.
This dysfunction was inhibited by SB-366791 (1 mg/kg, oral route [p.o.]), a selective TRPV1 antagonist, with a maximum inhibition (Imax) of 73.4 ± 15.5%, or by the single or 3-day-repeated administration of α-spinasterol (0.3 mg/kg, p.o.), with an Imax of 72.8 ± 17.8% and 78.9 ± 32.9%, respectively.
SB-366791 also inhibited the increase of the reserpine-induced immobility time, with an Imax of 100%, while α-spinasterol inhibited this parameter with an Imax of 98.2 ± 21.5% and 100%, by single or repeated administration, respectively.
The reserpine-induced mechanical allodynia and the thermal hyperalgesia were abolished by TRPV1-positive fibers desensitization induced by previous resiniferatoxin (RTX) administration.
In summary, the TRPV1 channel is involved in the development and maintenance of nociception and depressive-like behaviours in a fibromyalgia model, while the α-spinasterol has therapeutic potential to treat the pain and depression symptoms in fibromyalgia patients.