Opiorphin levels in fluids of burning mouth syndrome patients: a case-control study.
OBJECTIVE
Idiopathic Burning mouth syndrome (iBMS) is a poorly understood affection characterized by persistent pain in the oral cavity without any clinical or biological abnormality. Opiorphin is a natural inhibitor of enkephalin-inactivating ectopeptidases, mainly produced by salivary glands, that has demonstrated analgesic properties. The objective of the present case-control study was to test the hypothesis of a decrease in opiorphin levels in iBMS patients.


METHODS
Twenty-one iBMS patients and 21 matched controls subjects were included between 2011 and 2013. Submandibular and sublingual salivary, blood, and urinary opiorphin levels of iBMS patients were compared to controls.


RESULTS
Results are expressed as mean values ± SD and compared using the Wilcoxon Signed Rank test. Correlations were analyzed with Spearman coefficient. The level of significance was fixed at p < 0.05. Opiorphin levels in iBMS and controls were respectively (in ng/ml) in basal saliva: 37.8 ± 42.5 and 67.6 ± 188.9 (p = NS); stimulated saliva: 28.8 ± 25.3 and 31.1 ± 29.1 (p = NS); blood: 4.6 ± 5.4 and 1.9 ± 1.4 (p < 0.05); and urines: 68.5 ± 259.8 and 8.9 ± 6.2 (p = NS).


CONCLUSIONS
In conclusion, the lack of significative difference in salivary opiorphin levels between iBMS and controls does not favor a direct local role for opiorphin in the etiopathogeny of iBMS. However, higher blood opiorphin levels may reflect a systemic dysregulation in iBMS. Trial registration NCT02686359 https://clinicaltrials.gov/ct2/show/NCT02686359.
UFR Odontologie, Université Paris Diderot, 5, rue Garancière, 75006, Paris, France. yves.boucher@univ-paris-diderot.fr.|Groupe Hospitalier Pitie Salpêtrière Charles Foix, Paris, France. yves.boucher@univ-paris-diderot.fr.
Yves
Y
Boucher
UFR Odontologie, Université Paris Diderot, 5, rue Garancière, 75006, Paris, France.
Adeline
A
Braud
Institut Pasteur, Laboratory of Pharmacology of Pain, Paris, France.
Evelyne
E
Dufour
Groupe Hospitalier Pitie Salpêtrière Charles Foix, Paris, France.
Scarlette
S
Agbo-Godeau
UFR Odontologie, Université Paris Diderot, 5, rue Garancière, 75006, Paris, France.|Groupe Hospitalier Pitie Salpêtrière Charles Foix, Paris, France.
Vanessa
V
Baaroun
UFR Odontologie, Université Paris Diderot, 5, rue Garancière, 75006, Paris, France.|Groupe Hospitalier Pitie Salpêtrière Charles Foix, Paris, France.
Vianney
V
Descroix
Institut Pasteur, ICAReB platform, Paris, France.
Marie-Thérèse
MT
Guinnepain
Institut Pasteur, ICAReB platform, Paris, France.
Marie-Noëlle
MN
Ungeheuer
Institut Pasteur, ICAReB platform, Paris, France.
Catherine
C
Ottone
Institut Pasteur, Laboratory of Pharmacology of Pain, Paris, France.
Catherine
C
Rougeot
D015415:Biomarkers / Q000378:metabolism; D002054:Burning Mouth Syndrome / Q000378:metabolism* / Q000523:psychology; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000378:metabolism*; D010147:Pain Measurement; D012471:Salivary Proteins and Peptides / Q000378:metabolism*
D015415:Biomarkers; D009842:Oligopeptides; D012471:Salivary Proteins and Peptides; C517879:glutaminyl-arginyl-phenylalanyl-seryl-arginine
Blood; Burning mouth syndrome; Opiorphin; Pain; Saliva; Urine