Anti-inflammatory and anti-oxidant effect of Calea urticifolia lyophilized aqueous extract on lipopolysaccharide-stimulated RAW 264.7 macrophages

Authors: TORRES-RODRIGUEZ, MARIA - Autonomous University Of San Luis Potosi; GARCIA-CHAVEZ, ERIKA - Autonomous University Of San Luis Potosi; Berhow, Mark; DE MEJIA, ELVIRA - University Of Illinois

Submitted to: Journal of Ethnopharmacology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/2016
Publication Date: 4/30/2016
Citation: Torres-Rodriguez, M.L., Garcia-Chavez, E., Berhow, M., de Mejia, E.G. 2016. Anti-inflammatory and anti-oxidant effect of Calea urticifolia lyophilized aqueous extract on lipopolysaccharide-stimulated RAW 264.7 macrophages. Journal of Ethnopharmacology. 188:266-274.

Interpretive Summary: Calea urticifolia leaves (commonly known as negrito, hierba del negro, jaral de castilla, chilchaca, and juanislama) are traditionally used as a remedy to treat gastric ulcers, diabetes, and inflammation by the Xi’uy ancient native community of San Luis Potosi, Mexico. The aim of this study was to assess the effects of the aqueous extract ("teas") of C. urticifolia as anti-inflammatory and anti-oxidant using an anti-inflammatory bioassay system and to chemically evaluate the phenolic compounds contained in these extracts. In model cell culture studies, inflammation responses were reduced through inhibiting the production of particular enzymes involved in the inflammation response. Reactive oxygen species production was significantly inhibited in a dose-dependent manner. Moreover, the expression of several inflammatory genetic markers were also suppressed. A mix of bioactive phenolic compounds were found in these extracts which could be responsible for inhibiting induced inflammation and regulating oxidative stress through suppressing a signaling pathway and by inhibition of reactive oxygen species production in these cell culture systems. Therefore, these results support the traditional knowledge of C. urticifolia tea such as an anti-inflammatory and antioxidant agent.

Technical Abstract: Ethnopharmacological relevance: Calea urticifolia leaves are traditionally used as a remedy to treat gastric ulcers, diabetes, and inflammation by the Xi’uy ancient native community of San Luis Potosi, Mexico. Aim of the study: The aim was to assess the effects of the aqueous extract of the Mexican plant C. urticifolia as anti-inflammatory and anti-oxidant using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and to provide evidence on the phenolic compounds. Materials and methods: RAW 264.7 macrophages were stimulated with 1 ug/mL of LPS and treated with 10, 25 50, 75 y 100 ug/mL of Calea urticifolia lyophilized aqueous extract (CuAqE). Nitric oxide (NO) release, tumor necrosis factor alpha, prostaglandin E2 production, inducible nitric oxide synthase (iNOS), cyclooxygenase-2, nuclear factor-kB (NF-'B) p65, NF-'B p50 expression and reactive oxygen species (ROS) were measured; other pro-inflammatory proteins were measured with membrane antibody array. Phenolic compounds were analyzed by LC-ESI-MS. Results: Inflammation was inhibited by suppressing iNOS/NO pathway through inhibiting nucleus translocation of NF-'B p65 and p50 sub-units. ROS production was significantly (P <0.05) inhibited in a dose-dependent manner in LPS-stimulated macrophages. Moreover, the expression of inflammatory markers was suppressed (34.5–88.3%) by CuAqE. A mix of caffeoylquinic acid derivatives and flavonoid-glycosides were found in CuAqE. Conclusion: Phenolic compounds in CuAqE such as caffeoylquinic acid derivatives and flavonoid glycosides could be responsible for inhibiting LPS-induced inflammation and oxidative stress by iNOS/NO pathway through suppressing NF-kB signaling pathway and by inhibition of ROS production in RAW 264.7 macrophages. Therefore, these results support the traditional knowledge of C. urticifolia tea such as an anti-inflammatory and antioxidant agent.