Anti-inflammatory potential of Capparis spinosa L. in vivo in mice through inhibition of cell infiltration and cytokine gene expression

BACKGROUND Several chronic inflammatory diseases are characterized by inappropriate CD4+ T cell response. In the present study, we assessed the ability of Capparis spinosa L. (CS) preparation to orientate, in vivo, the immune response mediated by CD4+ T cells towards an anti-inflammatory response. METHODS The in vivo study was carried out by using the contact hypersensitivity (CHS) model in Swiss mice. Then we performed a histological analysis followed by molecular study by using real time RT-PCR. We also realized a phytochemical screening and a liquid-liquid separation of CS preparation. RESULTS Our study allowed us to detect a significantly reduced edema in mice treated with CS preparations relative to control. CS effect was dose dependent, statistically similar to that observed with indomethacin, independent of the plant genotype and of the period of treatment. Furthermore, our histology studies revealed that CS induced a significant decrease in immune cell infiltration, in vasodilatation and in dermis thickness in the inflammatory site. Interestingly, we showed that CS operated by inhibiting cytokine gene expression including IFNγ, IL-17 and IL-4. Besides, phytochemical screening of CS extract showed the presence of several chemical families such as saponins, flavonoids and alkaloids. One (hexane fraction) out of the three distinct prepared fractions, exhibited an anti-inflammatory effect similar to that of the raw preparation, and would likely contain the bioactive(s) molecule(s). CONCLUSIONS Altogether, our data indicate that CS regulates inflammation induced in vivo in mice and thus could be a source of anti-inflammatory molecules, which could be used in some T lymphocyte-dependent inflammatory diseases.