Salvia hispanica L. (chia) seed improves liver inflammation and endothelial dysfunction in an experimental model of metabolic syndrome

Abstract

The purposes of the present study were to analyze liver inflammation and endothelial dysfunction in an experimental model of metabolic syndrome (MS) induced by chronic administration of a sucrose-rich diet (SRD) and to evaluate the effects of chia seed as a therapeutic strategy. Male Wistar rats were fed with a reference diet (RD) for 6 months or a SRD for 3 months. Then, the latter group was randomly divided into two subgroups. One subgroup continued receiving the SRD for up to 6 months and the other was fed with a SRD where whole chia seed was incorporated as a source of dietary fat for the next 3 months (SRD + CHIA). Results showed that rats fed a SRD for a long period of time developed dyslipidemia, hyperglycemia, inflammation and endothelial dysfunction. Hepatic NAS, IL-1β, NFκB p65, PAI-1, and F4-80 expression, as well as MPO activity were significantly increased and IL-10 expression was significantly decreased; this was accompanied by increased plasma IL-6 and TNF-α levels in rats fed a SRD. In addition, serum and liver nitric oxide (NO) levels and nitric oxide synthase (NOS) were significantly increased in the SRD group. In addition, a significant increase in hepatic iNOS expression and a positive correlation of this with liver NFκB p65 was found. We observed a significant increase in hepatic intercellular adhesion molecule (ICAM), and a negative correlation of this with liver Nrf2 was found. The administration of chia seed for 3 months reversed dyslipidemia, hyperglycemia, inflammation and endothelial dysfunction. In the liver tissue, NAS, IL-1β, IL-10, NFκB p65, PAI-1, and F4-80 expression and MPO activity were normalized. Serum and liver NO and NOS levels and hepatic iNOS expression were decreased and this last one was associated with a decrease in liver NFκB p65 levels. Hepatic ICAM-1 was normalized and negatively correlated with liver NrF2 levels. This study showed new aspects of liver inflammation and endothelial dysfunction in dyslipidemic insulin resistant rats chronically fed with a sucrose-rich diet. In addition, we demonstrated new properties and molecular mechanisms associated with beneficial effects on inflammation and endothelial dysfunction of chia seed as a therapeutic strategy.