Opiorphin Level in Unstimulated Whole Saliva of Burning Mouth Syndrome Patients
Ruangsri S, DDS, MScDent, PhD1,2, Jorns TP, DDS, MDSc, PhD1,2, Chaiyarit P, DDS, PhD1
Affiliation : 1 Department of Oral Biomedical Sciences, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand 2 Neuroscience Research and Development Group (NRDG), Khon Kaen University, Khon Kaen, Thailand
Background : Burning mouth syndrome (BMS) is characterized by intense burning sensation of the tongue or other regions of the
oral mucosa with no known medical or dental cause. BMS is poorly understood condition which requires multidisciplinary
management. Opiorphin is a natural antinociceptor, previously identified from human saliva and demonstrated analgesic properties.
It has been reported to involve in pain pathways and could potentially be a biomarker for different types of physiological disorders.
Objective : Because of its abundance in the oral cavity, we aimed to measure the level of opiorphin in unstimulated whole saliva
(UWS) of patients with BMS.
Materials and Methods : Demographic data, history taking, oral examination and UWS samples were obtained from 20 BMS patients
before starting the drug treatment. Opiorphin levels were measured with a quantitative assay using commercially immunoenzymatic
competitive ELISA kit (cat No. E1779h, Wuhan, China) and compared to those of healthy control.
Results : UWS of 20 BMS patients (3 males and 17 females, average age 60.2 years old) were collected. The average concentration of
opiorphin in UWS of BMS patients was 1.25+0.79 ng/ml. The result demonstrated that opiorphin in BMS patients’ UWS was
significantly lower, compared to 4.16+0.82 ng/ml in the healthy control group (n = 3, 3 females, average age 50.6 years old).
Conclusion : Our results indicate that the decreased levels of opiorphin in UWS of patients with BMS may be associated with the
inhibition of analgesic property of encephalin, thereby causing chronic pain. To dates, knowledge on opiorphin’s involvement in
pain pathways has been controversial. Further study remains significant to understand the mechanistic role of opiorphin in chronic
orofacial pain.
Keywords : Burning mouth syndrome, Salivary opiorphin, Natural nociceptor
