AIM: To investigate the endothelial activation, inflammation, monocyte-endothelial cell binding and oxidative stress effects of four FD varieties.
METHODS: Human coronary artery endothelial cells (HCAEC) were incubated with different concentrations of aqueous ethanolic extracts of FD var. trengganuensis (FDT), var. kunstleri (FDK), var. deltoidea (FDD) and var. intermedia (FDI), together with LPS. Protein and gene expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular cell adhesion molecule-1 (ICAM-1), endothelial-leukocyte adhesion molecule-1 (E-selectin), interleukin-6 (IL-6), Nuclear factor-κB (NF-κB) p50 and p65 and endothelial nitric oxide synthase (eNOS) were measured using ELISA and QuantiGene plex, respectively. Adhesion of monocyte to HCAEC and formation of reactive oxygen species (ROS) were detected by Rose Bengal staining and 2'-7'-dichlorofluorescein diacetate (DCFH-DA) assay.
RESULTS: FDK exhibited the highest inhibition of biomarkers in relation to endothelial activation and inflammation, second in reducing monocyte binding (17.3%) compared to other varieties. FDK (25.6%) was also the most potent at decreasing ROS production.
CONCLUSION: FD has anti-atherogenic effects, possibly mediated by NF-κB and eNOS pathways; with FDK being the most potent variety. It is potentially beneficial in mitigating atherogenesis.
OBJECTIVE: This study investigated the potential of Stingless Bee Honey (SBH) to suppress lipopolysaccharide (LPS)-induced systemic acute inflammation in rats and to reveal the probable mechanism of action.
METHODS: Rats received 4.6 and 9.2 g/kg SBH for 7 days followed by a single injection of LPS after which blood samples were taken 6h later.
RESULTS: LPS induced liver, kidney, heart, and lung injury, were manifested by increased serum transaminases, alkaline phosphatase, creatine kinase, creatinine, and urea, along with multiple histological alterations, particularly leukocyte infiltration. Pro-inflammatory cytokines were elevated in the serum, and NF-κB p65, p38 MAPK, and HMGB-1 were significantly increased in different tissues of LPS-challenged rats. SBH prevented tissue injury, ameliorated pro-inflammatory cytokines, and suppressed NF-κB p65, p38 MAPK, and HMGB-1 in rats that had received LPS. In addition, SBH diminished reactive oxygen species (ROS) production, lipid peroxidation, and oxidative DNA damage, and enhanced glutathione and Nrf2 in LPS-treated rats.
CONCLUSION: SBH prevents systemic acute inflammation by suppressing NF-κB, p38 MAPK, HMGB-1, oxidative stress, and tissue injury in rats. Thus, SBH may represent an effective anti-inflammatory nutraceutical, pending further mechanistic studies.