Liposomal encapsulation of Chenopodium berlandieri extracts rich in oleanolic acid: improved bioactivities targeting metabolic syndrome prevention†

Abstract

Chronic inflammation and oxidative stress are major contributors to the development of metabolic syndrome conditions, including obesity, insulin resistance, dyslipidemia, and hypertension. These interconnected disorders significantly impact global health and demand preventive strategies. We encapsulated extracts from Chenopodium berlandieri—a Mexican edible pseudocereal rich in oleanolic acid (OA)—into liposomes to improve their bioactivity and delivery. Liposomes prepared via thin-film hydration followed by sonication showed particle sizes between 100 and 130 nm, narrow size distributions (PdI < 0.25), and zeta potentials from −6.3 to −7.6 mV. Encapsulation efficiencies exceeded 80%. In vitro release studies demonstrated sustained OA release, with over 80% released at 12 hours for OA and hydrolyzed extract liposomes. Cytotoxicity assays on human dermal fibroblasts confirmed lipid safety at physiologically relevant concentrations. Liposomal formulations significantly improved cellular antioxidant activity and nitric oxide inhibition compared to non-encapsulated samples. They also enhanced IL-10 production and reduced levels of pro-inflammatory markers including IL-6, TNF-α, and IL-1β. Additionally, liposomes downregulated COX-2 and inhibited elastase, collagenase, and hyaluronidase—enzymes involved in extracellular matrix (ECM) degradation, which contributes to tissue damage and inflammation in metabolic syndrome. These responses were most pronounced in liposomes loaded with hydrolyzed extracts. Overall, liposomal encapsulation enhanced the physicochemical stability, release behavior, and functional bioactivities of C. berlandieri bioactives, supporting their potential as functional food ingredients for metabolic syndrome prevention.