ABSTRACT
Objective: The aim of this study was to investigate the effects of dietary silicon-enriched spirulina (SES) on atherosclerosis.
Methods: Hamsters (six per group) on a high-fat (HF) diet received SES or non-enriched spirulina (both at 57 mg/kg body weight) daily. This corresponded to 0.57 mg silicon/kg body weight daily.
Results: The HF diet induced dyslipidemia, insulin resistance, oxidative stress, and vascular dysfunction. Compared with the HF group, SES attenuated increases of lipemia and prevented insulin resistance (IR) (P¼0.001). SES protected against oxidative stress through a reduction of heart (P¼0.006) and liver (P<0.0001) nicotinamide adenine dinucleotide phosphate-oxidaseactivity and by sparing the activity of superoxide dismutase (P¼0.0017) and glutathione perox-idase (P¼0.01861). SES decreased inflammation, lowering tumor necrosis factor-a (P¼0.0006) and interleukin-6 levels (P¼0.0112), decreasing polymorphonuclear cells and preventing nuclearfactor-kB activity (P¼0.0259). SES corrected plasma level of monocyte chemoattractant protein-1 (P¼0.0380), which was increased by the HF diet. Finally, SES supplementation prevented vascular and endothelial functions assessed respectively by the contractile response to the agonist phen-ylephrine and the relaxation induced by acetylcholine.
Conclusion: SES protects against metabolic imbalance, inflammation, oxidative stress, and vascular dysfunction induced by an HF diet, and could prevent the atherogenic processes. Synergistic effects between spirulina and silicon were observed.
