ABSTRACT
The aim of this paper was to explore the effects of Frankincense and Myrrh essential oil on transdermal absorption, and investigate the mechanism of permeation on the microstructure and molecular structure of stratum corneum. Through the determination of stratum corneum/medium partition coefficient of ferulicacid in Chuanxiong influenced by Frankincense and Myrrh essential oil, the effects of volatile oil of frankincense and Myrrh on the the microscopic and molecular structure of stratum corneum were explored by observation of skin stratum corneum structure under scanning electron microscopy, and investigation of frankincense and myrrh essential oil effects on the molecular structure of keratin and lipids in stratum corneum under Fourier transform infrared spectroscopy. The results showed that the oil could enhance the distribution of ferulic acid in the stratum corneum and medium, and to a certain extent damaged the imbricate structure of stratum corneum which was originally regularly, neatly, and closely arranged; some epidermal scales turned upward, with local peeling phenomenon. In addition, frankincense and myrrh essential oil caused the relative displacement of CH2 stretching vibration peak of stratum corneum lipids and amide stretching vibration peak of stratum corneum keratin, indicating that frankincense and myrrh essential oil may change the conformation of lipid and keratin in the stratum corneum, increase the bilayer liquidity of the stratum corneum lipid, and change the orderly and compact structure to increase the skin permeability and reduce the effect of barrier function. It can be concluded that Frankincense and Myrrh essential oil can promote the permeation effect by increasing the distribution of drugs in the stratum corneum and changing the structure of the stratum corneum.
ABSTRACT
The aim of this paper was to explore the effects of Frankincense and Myrrh essential oil on transdermal absorption in vitro of Chuanxiong, and to investigate the possible penetration mechanism of their essential oil from the perspective of skin blood perfusion changes. Transdermal tests were performed in vitro with excised mice skin by improved Franz diffusion cells. The cumulative penetration amounts of ferulic acid in Chuanxiong were determined by HPLC to investigate the effects of Frankincense and Myrrh essential oil on transdermal permeation properties of Chuanxiong. Simultaneously, the skin blood flows were determined by laser flow doppler. The results showed that the cumulative penetration amount of ferulic acid in Chuanxiong was (8.13±0.76) μg•cm⁻² in 24 h, and was (48.91±4.87), (57.80±2.86), (63.34±4.56), (54.17±4.40), (62.52±7.79) μg•cm⁻² respectively in Azone group, Frankincense essential oil group, Myrrh essential oil, frankincense and myrrh singly extracted essential oil mixture group, and frankincense and myrrh mixed extraction essential oil group. The enhancement ratios of each essential oil groups were 7.68, 8.26, 7.26, 8.28, which were slightly greater than 6.55 in Azone group. In addition, as compared with the conditions before treatment, there were significant differences and obvious increasing trend in blood flow of rats in Frankincense essential oil group, Myrrh essential oil group, frankincense and myrrh singly extracted essential oil mixture group, and frankincense and myrrh mixed extraction essential oil group when were dosed at 10, 20, 30, 10 min respectively, indicating that the skin blood flows were increased under the effects of Frankincense and Myrrh essential oil to a certain extent. Thus, Frankincense and Myrrh essential oil had certain effect on promoting permeability of Chuanxiong both before and after drug combination, and may promote the elimination of drugs from epidermis to dermal capillaries through increase of skin blood flow, thus enhancing the transdermal permeation amounts of drugs.