Caffeic acid phenethyl ester suppresses monocyte adhesion to the endothelium by inhibiting NF-κB/NOX2-derived ROS signaling.

Caffeic acid phenethyl ester (CAPE), one of the major polyphenols, exhibits anti-oxidative, anti-bacterial, and anti-cancer properties. Atherosclerosis is a chronic inflammatory disease, the progression of which is closely related to the accumulated adhesion of inflammatory monocytes/macrophages to the endothelium. We herein determined whether CAPE and its derivatives suppressed THP-1 cell adhesion to human umbilical vein endothelial cells (HUVEC).

Royal Jelly Constituents Increase the Expression of Extracellular Superoxide Dismutase through Histone Acetylation in Monocytic THP-1 Cells.

Extracellular superoxide dismutase (EC-SOD) is one of the main SOD isozymes and plays an important role in the prevention of cardiovascular diseases by accelerating the dismutation reaction of superoxide. Royal jelly includes 10-hydroxy-2-decenoic acid (10H2DA, 2), which regulates the expression of various types of genes in epigenetics through the effects of histone deacetylase (HDAC) antagonism. The expression of EC-SOD was previously reported to be regulated epigenetically through histone acetylation in THP-1 cells.

Suppression of EC-SOD by oxLDL During Vascular Smooth Muscle Cell Proliferation.

Reactive oxygen species (ROS) produced by endothelial cells and macrophages play important roles in atherogenesis because they promote the formation of oxidized low-density lipoproteins (oxLDL). Extracellular-superoxide dismutase (EC-SOD) is mainly produced by vascular smooth muscle cells (VSMCs), is secreted into the extracellular space, and protects cells from the damaging effects of the superoxide anion. Thus, the expression of EC-SOD in VSMCs is crucial for protecting cells against atherogenesis; however, oxLDL-induced changes in the expression of EC-SOD in VSMCs have not yet been examined.

Oxidized low-density lipoprotein accelerates the destabilization of extracellular-superoxide dismutase mRNA during foam cell formation.

Extracellular-superoxide dismutase (EC-SOD) is one of the main anti-oxidative enzymes that protect cells against the damaging effects of superoxide. In the present study, we investigated the regulation of EC-SOD expression during the oxidized low density lipoprotein (oxLDL)-induced foam cell formation of THP-1-derived macrophages. The uptake of oxLDL into THP-1-derived macrophages was increased and EC-SOD expression was decreased in a time-dependent manner by oxLDL.

Luteolin suppresses the differentiation of THP-1 cells through the Inhibition of NOX2 mRNA expression and the membrane translocation of p47phox.

Luteolin (1), a natural product occurring in many vegetables and fruits, is known to have several biological activities. Cluster for differentiation (CD) families, such as CD11b, -14, and -36, are expressed during pathological processes of atherosclerosis and are used broadly as markers of monocytic differentiation into macrophages. Herein, it was investigated whether 1 and three other flavonoids [chrysin (2), apigenin (3), and tricetin (4)] blocked 12-O-tetradecanoylphorbol 13-acetate (TPA)-triggered induction of CD families, which were induced through the activation of protein kinase C (PKC), mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK), and NADPH oxidase (NOX)-derived reactive oxygen species (ROS).

Epigenetic regulation of extracellular-superoxide dismutase in human monocytes.

Extracellular-superoxide dismutase (EC-SOD) is a major SOD isozyme mainly present in the vascular wall and plays an important role in normal redox homeostasis. We previously showed the significant reduction or induction of EC-SOD during human monocytic U937 or THP-1 cell differentiation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), respectively; however, its cell-specific expression and regulation have not been fully elucidated. It has been reported that epigenetic factors, such as DNA methylation and histone modification, are involved in several kinds of gene regulation.

TPA induces the expression of EC-SOD in human monocytic THP-1 cells: involvement of PKC, MEK/ERK and NOX-derived ROS.

Extracellular-superoxide dismutase (EC-SOD) is a major SOD isozyme mainly present in the vascular wall. EC-SOD is also observed in monocytes/macrophages, and its high expression contributes to the suppression of atherosclerosis by scavenging superoxide. The molecular mechanisms governing cell-specific expression of EC-SOD are mostly unknown, while the anti-oxidative effect of EC-SOD is well recognized.

Extracellular-superoxide dismutase expression during monocytic differentiation of U937 cells.

Leukemic cell lines, such as U937, THP-1, and HL60 cells, can differentiate into macrophages following exposure to various agents including 12-O-tetradecanoylphorbol-13-acetate (TPA) in vitro. It is well known that TPA enhances reactive oxygen species (ROS) generation through the activation of NADPH oxidase (NOX), and ROS act as mediators in TPA signaling. Extracellular-superoxide dismutase (EC-SOD) is a major anti-oxidative enzyme that protects the cells from damaging effects of superoxide.