TY - JOUR
T1 - The VGF-derived peptide TLQP-21
T2 - A new modulatory peptide for inflammatory pain
AU - Rizzi, Roberto
AU - Bartolomucci, Alessandro
AU - Moles, Anna
AU - D'Amato, Francesca
AU - Sacerdote, Paola
AU - Levi, Andrea
AU - La Corte, Giorgio
AU - Ciotti, Maria Teresa
AU - Possenti, Roberta
AU - Pavone, Flaminia
PY - 2008/8/15
Y1 - 2008/8/15
N2 - Vgf, is a neuro-endocrine specific gene encoding for a large protein precursor of different peptides. A role for VGF in pain modulation has been suggested from immunohistochemical studies showing VGF mRNA widely expressed in primary sensory neurons. In this study, the presence of VGF on the primary sensory afferents in mice was confirmed by showing its immunostaining in cultured neurons of dorsal root ganglia in secretory granule varicosities colocalized with Substance P. Moreover, the functional role of a C-terminal internal VGF-derived peptide, i.e. TLQP-21, was assessed by investigating its peripheral (1, 2, 4, 8 mM) and central (1, 2, 4 mM) effects on inflammatory pain in the formalin test. A significant increase of pain-related licking response following peripheral injection of TLQP-21 (4 and 8 mM) was observed in the second inflammatory phase of the test. In addition, an increase in licking response was detected when 4 mM of the peptide was injected alone without formalin. On the other hand, the central administration of TLQP-21 induced an U-shaped curve, with the dose of 2 mM being analgesic during the second phase. This study shows for the first time that a VGF-derived peptide may be involved in inflammatory pain in vivo and demonstrates a different action for TLQP21 at the peripheral and central levels of the nociceptive pathways.
AB - Vgf, is a neuro-endocrine specific gene encoding for a large protein precursor of different peptides. A role for VGF in pain modulation has been suggested from immunohistochemical studies showing VGF mRNA widely expressed in primary sensory neurons. In this study, the presence of VGF on the primary sensory afferents in mice was confirmed by showing its immunostaining in cultured neurons of dorsal root ganglia in secretory granule varicosities colocalized with Substance P. Moreover, the functional role of a C-terminal internal VGF-derived peptide, i.e. TLQP-21, was assessed by investigating its peripheral (1, 2, 4, 8 mM) and central (1, 2, 4 mM) effects on inflammatory pain in the formalin test. A significant increase of pain-related licking response following peripheral injection of TLQP-21 (4 and 8 mM) was observed in the second inflammatory phase of the test. In addition, an increase in licking response was detected when 4 mM of the peptide was injected alone without formalin. On the other hand, the central administration of TLQP-21 induced an U-shaped curve, with the dose of 2 mM being analgesic during the second phase. This study shows for the first time that a VGF-derived peptide may be involved in inflammatory pain in vivo and demonstrates a different action for TLQP21 at the peripheral and central levels of the nociceptive pathways.
KW - Behaviour
KW - DRG
KW - Formalin pain
KW - Immunofluorescence
KW - Mice
KW - Substance P
UR - http://www.scopus.com/inward/record.url?scp=46149096183&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=46149096183&partnerID=8YFLogxK
U2 - 10.1016/j.neulet.2008.06.018
DO - 10.1016/j.neulet.2008.06.018
M3 - Article
C2 - 18586396
AN - SCOPUS:46149096183
VL - 441
SP - 129
EP - 133
JO - Neuroscience Letters
JF - Neuroscience Letters
SN - 0304-3940
IS - 1
ER -