Assessment of Dermal Safety of Scutellaria baicalensis Aqueous Extract Topical Application on Skin Hypersensitivity

Abstract

Scutellaria baicalensis has been used as a traditional herbal medicine for bronchitis, hepatitis, and allergic diseases. The root of Scutellaria baicalensis contains active flavonoid components, including baicalin, baicalein, wogonoside, and wogonin, which have pharmaceutical properties. In the present study, the antiallergic properties of a standardized aqueous extract of S. baicalensis were evaluated, and the skin toxicity of its dermal application was also determined. The in vivo and in vitro assays were performed by using the β-hexosaminidase assay in rat basophilic leukemia cells (RBL-2H3) and cutaneous skin reaction in BALB/c mice, respectively. In addition, the acute dermal irritation/corrosion test was carried out in New Zealand white rabbits, and the skin sensitization test was conducted by Buhlerʼs method in Hartley guinea pigs to estimate the safety of the standardized aqueous extract of S. baicalensis for topical application. β-Hexosaminidase release in RBL-2H3 was markedly decreased following treatment with the standardized aqueous extract of S. baicalensis. It also ameliorated antigen-induced ear swelling compared with the control group in BALB/c mice. In the toxicological studies, it did not induce any dermal irritation/corrosion in rabbits or skin sensitization in guinea pigs. Although still limited, these results concerning the toxicological effects of S. baicalensis could be an initial step toward the topical application of S. baicalensis extracts on hypersensitive skin.

Key words

Scutellaria baicalensis - Lamiaceae - topical application - skin hypersensitivity - dermal toxicity - β-hexosaminidase

• References

• 1 Gao ZH, Huang KX, Xu HB. Protective effects of flavonoids in the roots of Scutellaria baicalensis Georgi against hydrogen peroxide-induced oxidative stress in HS-SY5Y cells. Pharmacol Res 2001; 43: 173-178
• 2 Kim DH, Cho KH, Moon SK, Kim YS, Kim DH, Choi JS, Chung HY. Cytoprotective mechanism of baicalin against endothelial cell damage by peroxynitrite. J Pharm Pharmacol 2005; 57: 1581-1590
• 3 Lai MY, Chen CC, Hsiu SL, Chao PDL. Analysis and comparison of baicalin, baicalein and wogonin contents in traditional decoctions and commercial extracts of Scutellariae Radix. J Food Drug Anal 2001; 9: 145-149
• 4 Chang YL, Shen JJ, Wung BS, Cheng JJ, Wang DL. Chinese herbal remedy wogonin inhibits monocyte chemotactic protein-1 gene expression in human endothelial cells. Mol Pharmacol 2001; 60: 507-513
• 5 Hamada H, Hiramatsu M, Edamatsu R, Mori A. Free-radical scavenging action of baicalein. Arch Biochem Biophys 1993; 306: 261-266
• 6 Li HB, Jiang Y, Chen F. Separation methods used for Scutellaria baicalensis active components. J Chromatogr B 2004; 812: 277-290
• 7 Jung HS, Kim MH, Gwak NG, Im YS, Lee KY, Sohn Y, Choi H, Yang WM. Antiallergic effects of Scutellaria baicalensis on inflammation in vivo and in vitro . J Ethnopharmacol 2012; 141: 345-349
• 8 Kim DS, Son EJ, Kim M, Heo YM, Nam JB, Ro JY, Woo SS. Antiallergic herbal composition from Scutellaria baicalensis and Phyllostachys edulis . Planta Med 2010; 76: 678-682
• 9 Kimura Y, Sumiyoshi M. Effects of various flavonoids isolated from Scutellaria baicalensis roots on skin damage in acute UVB-irradiated hairless mice. J Pharm Pharmacol 2011; 63: 1613-1623
• 10 Chiu HY, Tsai TF. Topical use of systemic drugs in dermatology: a comprehensive review. J Am Acad Dermatol 2011; 65: 1048-1053
• 11 Guy RH, Maibach HI. Drug delivery to local subcutaneous structures following topical administration. J Pharm Sci 1983; 72: 1375-1380
• 12 Song J, Zheng H, Seo HJ, Ji GE. Effect of oral administration of Scutellaria baicalensis root extract on atopic dermatitis-like skin lesion induced by oxazolone in hairless mice. J Korean Soc Appl Biol Chem 2012; 55: 175-181
• 13 Ikawati Z, Wahyuono S, Maeyama K. Screening of several Indonesian medicinal plants for their inhibitory effect on histamine release from RBL-2H3 cells. J Ethnopharmacol 2001; 75: 249-256
• 14 Fischer MJ, Paulussen JJ, Horbach DA, Roelofsen EP, van Miltenburg JC, de Mol NJ, Janssen LH. Inhibition of mediator release in RBL-2H3 cells by some H1-antagonist derived anti-allergic drugs: relation to lipophilicity and membrane effects. Inflamm Res 1995; 44: 92-97
• 15 Bak JP, Kim JB, Park JH, Yang YJ, Kim IS, Choung ES, Kang SC. Screening and compound isolation from natural plants for anti-allergic activity. J Korean Soc Appl Biol Chem 2011; 54: 367-375
• 16 Draize JH, Woodgard G, Calvery HO. Methods for the study of irritation and toxicity of substances applied topically to the skin and mucous membranes. J Pharmacol Exp Ther 1944; 82: 377-390
• 17 Gao J, Sanchez-Medina A, Pendry BA, Hughes MJ, Webb GP, Corcoran O. Validation of a HPLC method for flavonoid biomarkers in skullcap (Scutellaria) and its use to illustrate wide variability in the quality of commercial tinctures. J Pharm Pharm Sci 2008; 11: 77-87
• 18 Inagaki N, Shibata T, Itoh T, Suzuki T, Tanaka H, Nakamura T, Akiyama Y, Kawagishi H, Nagai H. Inhibition of IgE-dependent mouse triphasic cutaneous reaction by a boiling water fraction separated from mycelium of Phellinus linteus . Evid Based Complement Alternat Med 2005; 2: 369-374