In vitro Evidence

Standardized curcuminoid extract (Curcuma longa l.) decreases gene expression related to inflammation and interacts with associated microRNAs in human umbilical vein endothelial cells (HUVEC)
Food Funct.2012;3:1286–93
Chronic inflammation induced by pathogenic bacterial or viral infection, or other factors play a crucial role in the progression of atherosclerosis. Additionally, other pro-inflammatory mediators like intercellular adhesion molecules (ICAMs) and vascular cell adhesion molecule-1 (VCAM-1), and endothelial-selection (E-selectin) are known to be involved in causing endothelial dysfunction and tissue injury. Studies have discussed about the role of miRNAs (miRNA-126 and miRNA-146a), regulatory RNAs, during inflammatory process.

Studies have demonstrated effects of natural compounds, such as Curcuminoids on inflammation-involved miRNAs in conditions like cancer and apoptosis. However, protective role of Curcuminoids and involvement of miRNAs against chronic inflammation and related endothelial dysfunction is yet to be determined.

To explicate involvement of miRNA-126 and miRNA-146a in the anti-inflammatory effects of Curcuminoids in human umbilical vein endothelial cells (HUVEC).

Study Design:
  • Cell viability assay was performed in the presence of Curcuminoids for 24 h
  • Intracellular reactive oxygen species (ROS) generation was determined by stimulating HUVEC with E. coli lipopolysaccharides (LPS) (1 µg/mL) after pre-treating with varying concentrations of Curcuminoids (0–10 mg/L) for 60 min
  • mRNA analysis was done on cells pre-treated with varying concentrations of Curcuminoids (0–5 mg/L) for 30 min. followed by LPS-challenge for 24 h, and MicroRNA analysis was carried out using qRT-PCR
  • Furthermore, western-blot analysis and multiplex bead assay were performed to evaluate protein expression
Results and Discussion:
  • Treatment with Curcuminoids at varying concentrations resulted no change in cell viability and showed protection against ROS generation as well
  • Curcuminoids treatment also down-regulated the LPS-challenge induced mRNA and protein levels of pro-inflammatory mediators, such as NF-ĸB, IL-6, TNF-α
  • In addition, LPS-induced up-regulation of miRNA 146a was inhibited by Curcuminoids. Similarly, Curcuminoids decreased the mRNA expression of VCAM-1 and ICAM-1

It was concluded that Curcuminoids exhibit anti-inflammatory effects in HUVEC.