High Dietary Kuding Tea Extract Supplementation Induces Hepatic Xenobiotic-Metabolizing Enzymes-A 6-Week Feeding Study in Mice.

Kuding tea (KT) is a traditional Chinese beverage rich in plant bioactives that may exhibit various health benefits. However, little is known about the safety of KT extract (KTE) when consumed long term at high doses as a dietary supplement. Therefore, in this study, we investigated aspects of the safety of KTE.

Anti-obesity effects of α-cyclodextrin-stabilized 4-methylthio-3-butenyl isothiocyanate from daikon ( var. ) in mice.

4-Methylthio-3-butenyl isothiocyanate (MTBI) is a pungent bioactive constituent found in daikon. However, MTBI is immediately hydrolyzed to 3-hydroxy-methylene-2-thioxopyrrolidine in grated daikon. In this study, we evaluated whether MTBI in grated daikon complexed with α-cyclodextrin (αCD) has anti-obesity effects in mice.

Dietary α-cyclodextrin modifies gut microbiota and reduces fat accumulation in high-fat-diet-fed obese mice.

We investigated the effect of α-cyclodextrin (α-CD) on the bacterial populations of gut microbiota, production of organic acids, and short-chain fatty acids (SCFAs), and lipid metabolism in obese mice induced by feeding a high-fat diet (HFD). Male C57BL/6J mice were assigned to three diet groups: normal diet (ND) (5% [w/w] fat), HFD (35% [w/w] fat), and HFD (35% [w/w] fat) + 5.5% (w/w) α-CD for 16 weeks.

Bioavailability of an R-α-Lipoic Acid/γ-Cyclodextrin Complex in Healthy Volunteers.

R-α-lipoic acid (R-LA) is a cofactor of mitochondrial enzymes and a very strong antioxidant. R-LA is available as a functional food ingredient but is unstable against heat or acid. Stabilized R-LA was prepared through complexation with γ-cyclodextrin (CD), yielding R-LA/CD.

Investigation of Enantioselective Membrane Permeability of α-Lipoic Acid in Caco-2 and MDCKII Cell.

α-Lipoic acid (LA) contains a chiral carbon and exists as two enantiomers (R-α-lipoic acid (RLA) and S-α-lipoic acid (SLA)). We previously demonstrated that oral bioavailability of RLA is better than that of SLA. This difference arose from the fraction absorbed multiplied by gastrointestinal availability (F(a) × F(g)) and hepatic availability (F(h)) in the absorption phase.

Enantioselective Pharmacokinetics of α-Lipoic Acid in Rats.

α-Lipoic acid (LA) is widely used for nutritional supplements as a racemic mixture, even though the R enantiomer is biologically active. After oral administration of the racemic mixture (R-α-lipoic acid (RLA) and S-α-lipoic acid (SLA) mixed at the ratio of 50:50) to rats, RLA showed higher plasma concentration than SLA, and its area under the plasma concentration-time curve from time zero to the last (AUC) was significantly about 1.26 times higher than that of SLA.

Isomeric effects of anti-diabetic α-lipoic acid with γ-cyclodextrin.

Aims: Previous studies reported the anti-diabetic effects of α-lipoic acid (αLA) isomers: racemic-αLA, R-αLA, or S-αLA. Previously, we examined the anti-diabetic effects of αLA administered as a food additive, but were unable to demonstrate the differences among different isomers. In this study, αLAs were complexed with γ-cyclodextrin (γCD) for the stability.

Effect of γ-Cyclodextrin Inclusion Complex on the Absorption of R-α-Lipoic Acid in Rats.

R-α-lipoic acid (RLA) is an endogenous organic acid, and works as a cofactor for mitochondrial enzymes and as a kind of antioxidant. Inclusion complexes of RLA with α-, β- or γ-cyclodextrins (CD) were prepared and orally administered as a suspension to rats. Among them, RLA/γ-CD showed the highest plasma exposure, and its area under the plasma concentration-time curve (AUC) of RLA was 2.

A study on the inhibitory mechanism for cholesterol absorption by α-cyclodextrin administration.

Background: Micelle formation of cholesterol with lecithin and bile salts is a key process for intestinal absorption of lipids. Some dietary fibers commonly used to reduce the lipid content in the body are thought to inhibit lipid absorption by binding to bile salts and decreasing the lipid solubility. Amongst these, α-cyclodextrin (α-CD) is reportedly one of the most powerful dietary fibers for decreasing blood cholesterol.