Unravelling Effects of Rosemary (Rosmarinus officinalis L.) Extract on Hepatic Fat Accumulation and Plasma Lipid Profile in Rats Fed a High-Fat Western-Style Diet.

The objective of the study was to investigate the preventive effect on obesity-related conditions of rosemary (Rosmarinus officinalis L.) extract (RE) in young, healthy rats fed a high-fat Western-style diet to complement the existing knowledge gap concerning the anti-obesity effects of RE in vivo. Sprague Dawley rats (71.3 ± 0.46 g) were fed a high-fat Western-style diet (WD) or WD containing either 1 g/kg feed or 4 g/kg feed RE for six weeks. A group fed standard chow served as a negative control. The treatments did not affect body weight; however, the liver fat percentage was reduced in rats fed RE, and NMR analyses of liver tissue indicated that total cholesterol and triglycerides in the liver were reduced. In plasma, HDL cholesterol was increased while triglycerides were decreased. Rats fed high RE had significantly increased fasting plasma concentrations of Glucagon-like peptide-1 (GLP-1). Proteomics analyses of liver tissue showed that RE increased enzymes involved in fatty acid oxidation, possibly associated with the higher fasting GLP-1 levels, which may explain the improvement of the overall lipid profile and hepatic fat accumulation. Furthermore, high levels of succinic acid in the cecal content of RE-treated animals suggested a modulation of the microbiota composition. In conclusion, our results suggest that RE may alleviate the effects of consuming a high-fat diet through increased GLP-1 secretion and changes in microbiota composition.

Mucopenetrating polymer - Lipid hybrid nanovesicles as subunits in alginate beads as an oral formulation.

Crossing the intestinal mucus layer remains a great hurdle in oral drug delivery. The viscous mucus gel protects the body from pathogens but simultaneously traps many types of delivery vehicles, limiting their therapeutic efficacy. We report the assembly of mucopenetrating PEG-based polymer-lipid hybrid vesicles encapsulated in mucoadhesive alginate carriers aiming to increase their residence time in the intestine. The stability of the formulations was evaluated in simulated gastrointestinal conditions, showing negligible subunit leakage in the gastric fluid but a substantial release in the intestinal fluid. Mucopenetration of the free and encapsulated subunits was first demonstrated in vitro in a microfluidic set-up filled with reconstituted porcine mucus and in a mucus-covered co-culture of Caco-2 cells and HT29-MTX-E12 cells. Finally, the free and encapsulated subunits remained adhered in close proximity to the intestinal epithelium after oral administration to rats while the alginate carriers were washed away. In conclusion, the double-encapsulated system with combined mucoadhesive and mucopenetrating properties is a promising alternative drug carrier for oral delivery.