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Cytochrome P450 (CYP) epoxygenases and their metabolic products, epoxyeicosatrienoic acids (EETs), have been proposed as important therapeutic targets in the brain. However, CYP expression can be modified by the presence of diverse pro-inflammatory cytokines and the subsequent activation of the NF-κB pathway. It has been indicated that CYP epoxygenases are down-regulated by inflammation in the heart, kidney and liver. However, up to this point, there has been no evidence regarding regulation of CYP epoxygenases during inflammation in the brain. Therefore, in order to explore the effects of inflammation and NF-κB activation in CYP2J3 and CYP2C11 regulation, rat primary astrocytes cultures were treated with LPS with and without IMD-0354 (selective NF-κB inhibitor). Cyp2j3 and Cyp2c11 mRNA expression was determined by qRT-PCR; protein expression was determined by immunofluorescence and by Western Blot and total epoxygenase activity was determined by the quantification of EETs by ELISA. NF-κB binding sites in Cyp2j3 and Cyp2c11 promoter regions were bioinformatically predicted and Electrophoretic Mobility Shift Assays (EMSA) were performed to determine if each hypothetic response element was able to bind NF-κB complexes. Results shown that LPS treatment is able to down-regulate astrocyte CYP2J3 and CYP2C11 mRNA, protein and activity. Additionally, we have identified NK-κB as the transcription factor involved in this regulation.

Curcumin has protective effects against toxic agents and shows preventive properties for various diseases. Particulate material with an aerodynamic diameter of ≤10 μm (PM10) and titanium dioxide nanoparticles (TiO2-NPs) induce endothelial dysfunction and activation. We explored whether curcumin is able to attenuate different events related to endothelial activation. This includes adhesion, expression of adhesion molecules and oxidative stress induced by PM10 and TiO2-NPs. Human umbilical vein endothelial cells (HUVEC) were treated with 1, 10 and 100 μM curcumin for 1 h and then exposed to PM10 at 3 μg/cm2 or TiO2-NPs at 10 μg/cm2. Cell adhesion was evaluated by co-culture with U937 human myelomonocytic cells. Adhesion molecules expression was measured by flow cytometry after 3 or 24 h of exposure. Oxidative stress was determined by 2,7-dichlorodihydrofluorescein (H2DCF) oxidation. PM10 and TiO2-NPs induced the adhesion of U937 cells and the expression of E- and P-selectins, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1). The expression of E- and P-selectins matched the adhesion of monocytes to HUVEC after 3 h. In HUVEC treated with 1 or 10 μM curcumin, the expression of adhesion molecules and monocytes adhesion was significantly diminished. Curcumin also partially reduced the H2DCF oxidation induced by PM10 and TiO2-NPs. Our results suggest an anti-inflammatory and antioxidant role by curcumin attenuating the activation caused on endothelial cells by exposure to particles. Therefore, curcumin could be useful in the treatment of diseases where an inflammatory process and endothelial activation are involved.

Tumor microenvironment is an important promoter of tumorigenesis in all forms of breast cancer and has been associated with the risk of metastasis in the different breast cancer subtypes including the more frequent luminal subtypes that encompass 60% of cancer patients. Adhesive properties of endothelial cells (ECs) are strikingly affected during cancer cell dissemination and are related to functional changes of adhesion receptors. The contribution of tumor secreted factors to tumor‑EC adhesion represents a therapeutic opportunity for breast cancer metastasis. Conditioned medium (CM) of tumor cells can be used as a model to study the role of the secreted molecules to the tumor microenvironment. We explored transcriptomic changes associated to a pro‑adhesive phenotype in primary human umbilical vein endothelial cells (HUVECs) treated with CM of the breast cancer cell line ZR75.30 or with TNF for 3 h. Selected genes were used to validate the microarray through RT‑qPCR. The bioinformatic analysis identified NFκB as the main regulator of the pro-adhesive phenotype and this was confirmed by pharmacological inhibition of NFκB pathway with BAY 11‑7085. The changes induced by ZR75.30‑CM mimic those promoted by TNF and display changes in the expression of genes related to inflammatory response, wound healing, extracellular matrix, cytokines, metabolism and cell communication. Despite the abundance of G‑CSF, IL‑8, IL‑6 and VEGF in the ZR75.30‑CM and the confirmed activation of STAT3 and VEGFR2 pathways, our results suggest dominance of NFκB as a central controller of the transcriptomic response of ECs to breast cancer cells leading to expression of cell adhesion receptors.