No. 66 Enhancement of bioavailability of R-α lipoic acid by γ-cyclodextrin in human healthy volunteers

Background

Our company have attractive technologies in functional food and personal care fields which raise the water solubility, stability and bioavailability of a functional ingredient by using the inclusion property of cyclodextrin (CD).

In spite of high anti-aging functions of R-α lipoic acid, its stability and bioavailability are fairly low. So some of health benefits of R-α lipoic acid can not be shown up easily. Recently, we succeeded the enhancement of bioavailability of R-α lipoic acid with γ-CD in rats (* please refer to the newest result of research "47th" of our homepage for details.). That effect was achieved through the stabilization of R-α lipoic acid by complexation with γ-CD. Therefore, we commercialized "R-α lipoic acid-γ-CD complex" as functional health food and cosmetics materials.

In this research, the bioavailability of R-α lipoic acid with γ-CD was also examined in human healthy volunteers.

Health benefits of R-α lipoic acid

Study design

This study was approved by the ethics committees of Kobe university.

single-dose crossover comparative bioavailability trial consisted of two studies (Study 1 and Study 2) was conducted.

Human subject

Healthy 6 males aged 20-45 years

Test material

R-α lipoic acid -γ-CD : 6g (containing 600mg of R-α lipoic acid) / dose

Comparative material

R-α lipoic acid : 600mg /dose

Collection points of blood

Result : Effect of γ-CD on the bioavailability R-α lipoic acid

Fig. 1

Plasma concentration time-profiles of R-α lipoic acid in human healthy volunteers after oral supplementation (n=6,mean±S.D.)

The bioavailability of R-α lipoic acid was enhanced by complexation with γ-CD.

Conclusion

• The bioavailability of R-α lipoic acid was enhanced by complexation with γ-CD in not only rats but also human healthy volunteers.
• Any adverse effects were not shown by the single-dose of R-α lipoic acid-γ-CD complex.