METHODS: HCAECs were stimulated for 24 hours (h) with 200 µg/ml of Lipopolysaccharides (LPS) and different concentrations of NSO (55, 110, 220, 440 µg/ml) or TQ (4.5, 9.0, 18.0, 36.0 µm). The effects of NSO and TQ on gene and protein expressions were measured using multiplex gene assay and ELISA assay, respectively. Rose Bengal assay was used to analyse monocyte binding activity.
RESULTS: NSO and TQ significantly reduced ICAM-1 and VCAM-1 gene and protein expressions. TQ showed significant reduction activity of the biomarkers in dose dependent manner. HCAECs pre-treated with NSO and TQ for 24 h significantly lowered monocytes adherence compared to non-treated HCAECs.
CONCLUSIONS: NSO and TQ supplementation have anti-atherogenic properties and inhibit monocytes' adherence to HCAECs via down-regulation of ICAM-1 expression. NSO could potentially be incorporated in standard treatment regimens to prevent atherosclerosis and its related complications.
OBJECTIVES: (1) To compare the concentrations of biomarkers of inflammation, endothelial activation and oxidative stress in subjects with low HDL-c compared to normal HDL-c; (2) To examine the association and correlation between HDL-c and these biomarkers and (3) To determine whether HDL-c is an independent predictor of these biomarkers.
METHODS: 422 subjects (mean age±SD = 43.2±11.9 years) of whom 207 had low HDL-c concentrations (HDL-c <1.0 mmol/L and <1.3 mmol/L for males and females respectively) and 215 normal controls (HDL-c ≥1.0 and ≥1.3 mmol/L for males and females respectively) were recruited in this study. The groups were matched for age, gender, ethnicity, smoking status, diabetes mellitus and hypertension. Fasting blood samples were collected for analysis of biomarkers of inflammation [high-sensitivity C-reactive protein (hsCRP) and Interleukin-6 (IL-6)], endothelial activation [soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), soluble Intercellular Adhesion Molecule-1 (sICAM-1) and E-selectin)] and oxidative stress [F2-Isoprostanes, oxidized Low Density Lipoprotein (ox-LDL) and Malondialdehyde (MDA)].
RESULTS: Subjects with low HDL-c had greater concentrations of inflammation, endothelial activation and oxidative stress biomarkers compared to controls. There were negative correlations between HDL-c concentration and biomarkers of inflammation (IL-6, p = 0.02), endothelial activation (sVCAM-1 and E-selectin, p = 0.029 and 0.002, respectively), and oxidative stress (MDA and F2-isoprostane, p = 0.036 and <0.0001, respectively). Multiple linear regression analysis showed HDL-c as an independent predictor of IL-6 (p = 0.02) and sVCAM-1 (p<0.03) after correcting for various confounding factors.
CONCLUSION: Low serum HDL-c concentration is strongly correlated with enhanced status of inflammation, endothelial activation and oxidative stress. It is also an independent predictor for enhanced inflammation and endothelial activation, which are pivotal in the pathogenesis of atherosclerosis and atherosclerosis-related complications.