Increased expression of Trpv1 in peripheral terminals mediates thermal nociception in Fabry disease mouse model

J Lakomá, R Rimondini, A Ferrer Montiel… - Molecular …, 2016 - journals.sagepub.com
J Lakomá, R Rimondini, A Ferrer Montiel, V Donadio, R Liguori, M Caprini
Molecular pain, 2016journals.sagepub.com
Fabry disease is a X-linked lysosomal storage disorder caused by deficient function of the
alpha-galactosidase A (α-GalA) enzyme. α-GalA deficiency leads to multisystemic clinical
manifestations caused by the preferential accumulation of globotriaosylceramide (Gb3) in
the endothelium and vascular smooth muscles. A hallmark symptom of Fabry disease
patients is neuropathic pain that appears in the early stage of the disease as a result of
peripheral small fiber damage. The α-GalA gene null mouse model (α-GalA (−/0)) has …
Fabry disease is a X-linked lysosomal storage disorder caused by deficient function of the alpha-galactosidase A (α-GalA) enzyme. α-GalA deficiency leads to multisystemic clinical manifestations caused by the preferential accumulation of globotriaosylceramide (Gb3) in the endothelium and vascular smooth muscles. A hallmark symptom of Fabry disease patients is neuropathic pain that appears in the early stage of the disease as a result of peripheral small fiber damage. The α-GalA gene null mouse model (α-GalA(−/0)) has provided molecular evidence for the molecular alterations in small type-C nociceptors in Fabry disease that may underlie their hyperexcitability, although the specific mechanism remains elusive. Here, we have addressed this question and report that small type-C nociceptors from α-GalA(−/0) mice exhibit a significant increase in the expression and function of the TRPV1 channel, a thermoTRP channel implicated in painful heat sensation. Notably, male α-GalA(−/0) mice displayed a ≈2-fold higher heat sensitivity than wild-type animals, consistent with the augmented expression levels and activity of TRPV1 in α-GalA(−/0) nociceptors. Intriguingly, blockade of neuronal exocytosis with peptide DD04107, a process that inhibits among others the algesic membrane recruitment of TRPV1 channels in peptidergic nociceptors, virtually eliminated the enhanced heat nociception of α-GalA(−/0) mice. Together, these findings suggest that the augmented expression of TRPV1 in α-GalA(−/0) nociceptors may underly at least in part their increased heat sensitivity, and imply that blockade of peripheral neuronal exocytosis may be a valuable pharmacological strategy to reduce pain in Fabry disease patients, increasing their quality of life.
Sage Journals