Skullcap (Scutellaria Baicalensis) Hexane Fraction Inhibits the Permeation of Ovalbumin and Regulates Th1/2 Immune Responses.

Skullcap (Scutellaria baicalensis) is well known for its anti-inflammatory and anti-allergic effects. In our previous study, we found that skullcap could inhibit allergen permeation and regulate Th1/2 immune balance. To reveal the key fractions and components of skullcap, we fractionated skullcap extract into five fractions: hexane, chloroform, ethyl acetate, butanol, and water fraction. Among these fractions, the hexane fraction significantly suppressed the production of Th2-mediated cytokines (Interleukin (IL)-4, 5, 10 and 13) and increased Th1-mediated cytokines (Interferon (IFN)-γ and IL-12). Furthermore, the hexane fraction inhibited the permeation of ovalbumin (OVA), used as an allergen, across the intestinal epithelial cell monolayer. To confirm the active compounds in the hexane fraction, fatty acids were analyzed. Linoleic acid (LA, C18:2 (>59.7%)) was identified as the most important fatty acid in the skullcap hexane fraction. LA significantly suppressed IL-4 production and increased IFN-γ secretion, as well as inhibiting OVA permeation. Thus, LA significantly diminished the permeation of allergen by enhancing intestinal barrier function and regulated allergic responses to maintain Th1/Th2 immune balance.

Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers.

Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function.

Enhancing Effect of Trachelogenin from Trachelospermi caulis Extract on Intestinal Barrier Function.

Trachelospermi caulis is used widely as an herbal medicine in oriental countries to attenuate fever and pain. We wished to reveal the novel function of this herb and its active component on barrier function in intestinal epithelial cells. Monolayers of intestinal epithelial cells (Caco-2) were used to evaluate the transepithelial electrical resistance (TEER) and quantity of permeated ovalbumin (OVA) as indices of barrier function. T. caulis increased TEER values on cell monolayers and decreased OVA permeation across cell monolayers. To ascertain the active component of T. caulis, the extract was isolated to five fractions, and the effect of each of these fractions on intestinal barrier function examined. Chloroform and ethyl acetate fractions showed increased TEER values and decreased OVA flux. Chloroform and ethyl acetate fractions contained mainly trachelogenin and its glycoside, tracheloside. Trachelogenin increased TEER values and decreased OVA flux by enhancing the tight-junction protein occludin (but not tracheloside) in Caco-2 monolayers. These findings demonstrated that trachelogenin, an active component of T. caulis, might help to attenuate food allergy or inflammatory bowel disease through inhibition of allergen permeation or enhancement of the intestinal barrier.

Optimisation of microwave-assisted extraction for functional properties of Vitis coignetiae extract by response surface methodology.

BACKGROUND: Consumer preference for selection of natural substances, with their safe and beneficial effects on the human body as well as various physiological efficacies, is increasing. In this study, response surface methodology (RSM) was used to monitor the extraction characteristics of Vitis coignetiae (wild grape) and thereby optimise the functional properties of the resulting extract. RESULTS: A maximum total polyphenol content (TPC) of 415.74 mg per 100 g was obtained at a microwave power (MWP) of 102.36 W, an ethanol concentration (ETC) of 42.62% (by volume) and an extraction time (EXT) of 12.35 min. Electron-donating ability (EDA) reached a maximum of 69.20% at 125.65 W MWP, 41.81% ETC and 13.65 min EXT. The maximum nitrite-scavenging ability (NSA) obtained was 87.50% at 119.13 W MWP, 37.41% ETC and 13.20 min EXT. Superoxide dismutase (SOD) showed a maximum pseudo-activity (SDA) of 56.74% at 69.54 W MWP, 94.88% ETC and 10.32 min EXT. The effect of ETC was most prominent among the studied factors. CONCLUSION: Based on the superimposition of four-dimensional response surfaces with respect to TPC, EDA, NSA and SDA, the optimum ranges of extraction conditions were 70-150 W MWP, 30-50% ETC and 8-18 min EXT.