Anti‐Hyperglycemic Effects of Oils and Extracts Derived from Sea Buckthorn – A Comprehensive Analysis Utilizing In Vitro and In Vivo Models

Abstract

Scope Sea buckthorn (Hippophaes rhamnoides) is capable of ameliorating disturbed glucose metabolism in animal models and human subjects. Here, the effect of sea buckthorn oil as well as of extracts of fruits, leaves, and press cake on postprandial glucose metabolism is systematically investigated. Methods and results Sea buckthorn did neither exert decisive effects in an in vitro model of intestinal glucose absorption nor did it alter insulin secretion. However, sea buckthorn stimulates GLUT4 translocation to the plasma membrane comparable to insulin, indicative of increased glucose clearance from the circulation. Isorhamnetin is identified in all sea buckthorn samples investigated and is biologically active in triggering GLUT4 cell surface localization. Consistently, sea buckthorn products lower circulating glucose by ≈10% in a chick embryo model. Moreover, sea buckthorn products fully revert hyperglycemia in the nematode Caenorhabditis elegans while they are ineffective in Drosophila melanogaster under euglycemic conditions. Conclusion These data indicate that edible sea buckthorn products as well as by‐products are promising resources for hypoglycemic nutrient supplements that increase cellular glucose clearance into target tissues.

Improved Bioavailability and Bioaccessibility of Lutein and Isoflavones in Cultured Cells In Vitro through Interaction with Ginger, Curcuma and Black Pepper Extracts

“…For transport studies, cells were seeded at 5.5 × 10 5 cells/trans-well insert (ThinCert, 0.336 cm 2 , 0.4 μm pore diameter; Greiner-Bio One, Kremsmünster, Austria) and differentiated using Entero-STIM Intestinal Epithelium Differentiation Medium (Corning, Wiesbaden, Germany) supplemented with 1% penicillin/streptomycin and 0.1% MITO+ Serum Extender (Corning). Monolayer integrity was assessed by transepithelial electrical resistance (TEER) measurement with a Millicell-ERS-2 Voltohmmeter (Merck, Darmstadt, Germany) as described previously [ 20 ]. For experiments, differentiated cells were washed twice with HEPES buffer.…”

Novel Insight into the Formation of Odour—Active Compounds in Sea Buckthorn Wine and Distilled Liquor Based on GC–MS and E–Nose Analysis

“…Sea buckthorn ( Hippophae rhamnoides ), classified as a medicine food homology (MFH) plant, contains large amounts of vitamin C, carotene, flavones, linoleic acid and other bioactive substances [ 1 , 2 ]. For example, the vitamin C content of sea buckthorn juice (SJ) reaches 1000 mg/100 g, which is two to three times higher than that of kiwifruit ( Actinidia deliciosa ) [ 3 ].…”