Lysophosphatidylcholine 16:0 mediates chronic joint pain associated to rheumatic diseases through acid-sensing ion channel 3.

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"The authors thank Drs A. Baron, S. Diochot, J. Noel, and M. Salinas for helpful discussions, V. Friend and J. Salvi-Leyral for technical support, and V. Berthieux for secretarial assistance. The authors also thank Tycho Tullberg, MD, PhD, CEO of Stockholm Spine Center during the data collection period for generous support and for providing research facilities at Stockholm Spine Center. The authors thank orthopaedic surgeons Ingemar Gladh and Per Gerdin for patient recruitment and taking tissue samples during surgery at Ortho Center, Stockholm. Furthermore, the authors thank Carola Skärvinge, research nurse at Stockholm Spine Center for excellent logistic assistance and Azar Baharpoor, Department of Physiology and Pharmacology, Karolinska Insitutet for support and laboratory assistance. This work was supported by the Centre National de la Recherche Scientifique (CNRS), the Institut National de la Santé et de la Recherche Médicale (INSERM), the Association Française contre les Myopathies (AFM grant #19618), the Agence Nationale de la Recherche (ANR-11-LABX-0015-01 and ANR-17-CE16-0018) and the NeuroMod Institute of University Côte d'Azur (UCA). This work was also supported by the Conseil Regional Auvergne-Rhone-Alpes (project Ressourcement S3, Arth-Innov) and Feder as well as the French government IDEX-ISITE initiative 16-IDEX-0001 (CAP 20-25). The authors thank the multimodal imaging platform IVIA and CICS, Clermont-Ferrand, France, for in vivo imaging and electronic microscopy, respectively. The study has also received funding from Stockholm County Council, Swedish research Council (K2013-52X-22,199-01-3), and Eli Lilly, USA. The research leading to these results has also received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 602919 and from a generous donation from Leif Lundblad and family."

"Fifty patients suffering from different painful joint diseases (32 women and 18 men, average age, 68.6 years, range, 26-94 years), recruited in the Rheumatology Department of Nice University Hospital, France, participated and were distributed as follow: rheumatoid arthritis (RA, n = 6), chondrocalcinosis (CCA, n = 12), spondyloarthritis (SPA, n = 5), psoriatic arthritis (n = 4), gout (n = 5), and OA (n = 18). All subjects provided informed consent before inclusion, and the study was approved by the Nice University Institutional Review Board for Research on Human Subjects. By contrast with the first OA cohort, information about medications was not available for all patients excluding the possibility to perform correlation studies between LPC levels in synovial fluids and patient pain outcomes. The study has been conducted in accordance with the French national regulations regarding patient consent and ethical review. The study was registered in the ClinicalTrials.gov protocol registration system (NCT 01867840). All samples were obtained from patients with acute knee joint effusion requiring joint puncture for diagnosis and/or treatment. The synovial fluids remaining after biological analysis for patients' care were included in the present study and frozen at −80°C for future analysis."