Contents lists available at ScienceDirect Food and Chemical Toxicology journal homepage: www.elsevier.com/locate/foodchemtox Clinopodium vulgare L. (wild basil) extract and its active constituents modulate cyclooxygenase-2 expression in neutrophils Kristiana M. Amirova a , Petya Dimitrova b , Andrey S. Marchev a,c , Ina Y. Aneva d , Milen I. Georgiev a,c,* a Center of Plant Systems Biology and Biotechnology, 4000, Plovdiv, Bulgaria b Department of Immunology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Georgi Bonchev Str., 1113, Sofia, Bulgaria c Group of Plant Cell Biotechnology and Metabolomics, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 139 Ruski Blvd., 4000, Plovdiv, Bulgaria d Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria ARTICLE INFO Keywords: Wild basil Clinopodium vulgare L. NMR profiling Phenolic compounds COX-2 Neutrophils ABSTRACT Clinopodium vulgare L. (wild basil) has a wide range of ethnopharmacological applications and accumulates a broad spectrum of phenolic compounds, recognized for their anti-inflammatory and anticancer properties. The triggered cyclooxygenase-2 (COX-2) expression is creating an immunosuppressive microenvironment in the inflamed tissue and considered to be the main cause of failure of even new anticancer-/immune-therapies. Nowadays, selective and novel plant-derived COX-2 inhibitors with safe profile are subject of profound research interest. This study aimed to analyze the metabolic profile of C. vulgare and search for phenolic molecules with po- tential biological properties. By application of 1 H and 2D-NMR (Nuclear Magnetic Resonance) profiling, caffeic, chlorogenic acids and catechin were identified along with a bunch of primary and secondary metabolites. Further, the biological effect of C. vulgare extract (CVE) and its constituents on zymosan-induced COX-2 ex- pression and apoptosis of murine neutrophils have been studied. The CVE, caffeic and chlorogenic acids in- hibited zymosan-induced COX-2 expression in bone marrow neutrophils, in vitro and in vivo activated. The ob- tained data indicate that CVE may have a good potential to manipulate neutrophil functions, however, its action may depend on the cellular state, the inflammatory milieu and the relative content of caffeic and chlorogenic acid in the extract. 1. Introduction Clinopodium vulgare L. (wild basil; Lamiaceae) has diverse ethno- pharmacological applications and hence has been used for treatment of hemorrhagic disease, ulcer, diabetes, mastitis, prostatitis and skin in- flammation (Badisa et al., 2003). Contemporary studies revealed the multiple beneficial properties of C. vulgare aqueous or methanolic ex- tracts (CVEs), i.e. anticancer, anti-inflammatory, DNA-protective, anti- oxidant and antibacterial properties (Burk et al., 2009). Comprehensive investigations accentuate on the selective and tissue specific anticancer activity of the extracts against vast panel of human cancer cell lines (Badisa et al., 2003). However, to date, there is scarcity of information concerning the molecular mechanisms and targets of the anti-in- flammatory and anticancer activity of CVEs referenced to specific mo- lecule or multiple constituents that formulate the activity of the ex- tracts. Cyclooxygenases exist in two isoforms, and while COX-1 is con- stitutively expressed in the cells and has housekeeping functions, COX-2 is induced by inflammatory stimuli, which in turn accelerates the synthesis of prostaglandins, and stimulates cancer cells proliferation and their metastatic potential. Therefore, COX-2 is considered as a molecular target for the development of novel and selective (natural) anti-inflammatory drugs (Chen et al., 2019; Desai et al., 2018). Many plant-derived molecules, such as caffeic and chlorogenic acid, as well https://doi.org/10.1016/j.fct.2018.11.054 Received 22 September 2018; Received in revised form 21 November 2018; Accepted 24 November 2018 Abbreviations: BM, Bone marrow; COX-1, Cyclooxygenase-1; COX-2, Cyclooxygenase-2; CVE, Clinopodium vulgare extract; HO-1, Heme oxygenase-1; iNOS, Inducible nitric oxide synthase; NF-kB, Nuclear factor-kappa B; NSAIDs, Non-steroidal anti-inflammatory drugs; Nrf2, Nuclear factor erythroid 2 p45-related factor 2; MAPK, Mitogen-activated protein kinase; MPO, Myeloperoxidase; Myd88, Myeloid differentiation primary response 88; NMR, Nuclear magnetic resonance; PGE 2 , Prostaglandin E2; TLR, Toll-like receptor * Corresponding author. Center of Plant Systems Biology and Biotechnology, 4000, Plovdiv, Bulgaria. E-mail address: milengeorgiev@gbg.bg (M.I. Georgiev). Food and Chemical Toxicology 124 (2019) 1–9 Available online 24 November 2018 0278-6915/ © 2018 Elsevier Ltd. All rights reserved. T