In-Vitro Effect of Ammodaucus Leucotrichus Flower and Fruit Essential Oils on Nitric Oxide Production and Arginase Activity in Human Peripheral Blood Mononuclear Cells (PBMC) from Patients with Behçet Disease

Ammodaucus leucotrichus is an Algerian aromatic medicinal plant, widely known as "Oum-draiga or Kamoune-l'ibel". In folk medicine, the flower and fruit of this plant are widely used for the treatment of cough, fever, diarrhea, colic, and cold. In this study, we describe for the first time the modulatory effects of flower and fruit essential oils (EOs) of A. leucotrichus subsp. leucotrichus on NOS and Arginase activities and their regulation during Behcet disease, an auto-inflammatory vasculitis of unknown etiology. The EOs were obtained by Clevenger-hydrodistillation and their chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). The peripheral blood mononuclear cells of 20 patients and 15 control samples (PBMC) were cultured in RPMI-1640 and incubated with or without seeds and the flowers' essential oil from A. leucotrichus was dissolved in DMSO (0.01%). Culture supernatants were harvested after 24 h of incubation. NO and urea measurements were, respectively, performed by modified Griess and Berthelot methods. Our results show that essential oils for both fruits and flowers significantly reduce the production of NO production in a concentration-dependent manner. In contrast, significantly increased urea was noted in treated PBMC of BD patients. Our study suggests that EOs extracted from the flower and fruit of A. leucotrichus could have potential immuno-modulatory effects characterized by a down-regulation and up-regulation of NO and urea, respectively, probably by NOS/Arginase balance regulation.