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Research on the influence of Indigo Naturalis (青黛 Qing dai) in cosmetics on our skin's immune system
Indigo Naturalis (青黛 Qing dai)
Blue wonder from the traditional Chinese herb garden
Indigo naturalis has long been used in traditional Chinese medicine to
Eliminate detoxification, cool blood to stop bleeding, cleanse liver, extinguish fire, treat ulcers[1] , eczema, boils, skin inflammation and other diseases.[2] [3]
Research confirms
the effect of indigo naturalis in psoriasis[4] [5] [6] ,an anti-inflammatory[7], antibacterial[8] effect and that indigo naturalis inhibits the proliferation of skin cells.[9]
The ingredients of indigo naturalis reduce the development of plaques and inflammation in psoriasis. Studies found that it is not the individual isolated ingredients that cause skin improvement, but the interaction of all of them. [10] [11]
By treating psoriasis with indigo naturalis balm, all skin changes disappeared after 2 months and no symptoms appeared for more than 2 years afterwards.[12]
In a Chinese study, after eight weeks of treating moderate psoriasis with indigo naturalis, more than half of the patients experienced a 75% improvement. [13]
Indigo naturalis is also effective in nail psoriasis, which is more difficult to treat.[14] [15] [16]
[1] 复方青黛散的制备与临床应用 (Preparation and clinical application of compound Qingdai San)
Chongqing Weipu Information
[2] 青黛的临床应用 (Qingdai's ancient and modern applications)
Chongqing Weipu Information
[3] 青黛的临床应用 (Clinical application of Indigo Naturalis)
Chongqing Weipu Information
[4] Lin YK, Chang CJ, Chang YC, Wong WR, Chang SC, Pang JH. Clinical assessment of patients with recalcitrant psoriasis in a randomized, observer-blind, vehicle-controlled trial using indigo naturalis. Arch Dermatol. 2008 Nov;144(11):1457-64. doi: 10.1001/archderm.144.11.1457. PMID: 19015420.
pubmed
[5] Brattström, A. (2016). Woad (Isatis tinctoria) for treating psoriasis Zeitschrift für Phytotherapie, 37(02), 67-70.
[Thieme Connect]
[6] Lin, Y.‐K., See, L.‐C., Huang, Y.‐H., Chi, C.‐C. and Hui, R.‐Y. (2018), 治疗银屑病的青黛软膏中的靛玉红含量对比:一项随机、双盲、剂量对照试验. (Comparison of indirubin content in Qingdai ointment for treating psoriasis: a randomized, double-blind, dose-controlled trial )Br J Dermatol, 178: e104-e104.
wiley
[7] Kunikata, T., Tatefuji, T., Aga, H., Iwaki, K., Ikeda, M., & Kurimoto, M. (2000). Indirubin inhibits inflammatory reactions in delayed-type hypersensitivity. European journal of pharmacology, 410(1), 93-100.
[Science Direct]
[8] Chiang, Y. R., Li, A., Leu, Y. L., Fang, J. Y., & Lin, Y. K. (2013). An in vitro study of the antimicrobial effects of indigo naturalis prepared from Strobilanthes formosanus Moore. Molecules (Basel, Switzerland), 18(11), 14381–14396.
[PMC]
[9] Lin, Y. K., Wong, W. R., Chang, Y. C., Chang, C. J., Tsay, P. K., Chang, S. C., & Pang, J. H. S. (2007). The efficacy and safety of topically applied indigo naturalis ointment in patients with plaque-type psoriasis. Dermatology, 214(2), 155-161.
[Karger]
[10] Lin YK, Chen HW, Leu YL, et al. Indigo naturalis upregulates claudin-1 expression in human keratinocytes and psoriatic lesions. J Ethnopharmacol.2013;145(2):614-620; PMID: 23220199
[Science Direct]
[11] Lin YK, Leu YL, Huang TH, et al. Anti-inflammatory effects of the extract of indigo naturalis in human neutrophils. J Ethnopharmacol.2009;125(1):51-58; PMID: 19559779
[Science Direct]
[12] Lin, Y.-K., Yen, H.-R., Wong, W.-R., Yang, S.-H. and Pang, J.-H.S. (2006), Successful Treatment of Pediatric Psoriasis with Indigo naturalis Composite Ointment. Pediatric Dermatology, 23: 507-510.
wiley
[13] Cheng, H. M., Wu, Y. C., Wang, Q., Song, M., Wu, J., Chen, D., Li, K., Wadman, E., Kao, S. T., Li, T. C., Leon, F., Hayden, K., Brodmerkel, C., & Chris Huang, C. (2017). Clinical efficacy and IL-17 targeting mechanism of Indigo naturalis as a topical agent in moderate psoriasis. BMC complementary and alternative medicine, 17(1), 439.
[PMC]
[14] Liang, C. Y., Lin, T. Y., & Lin, Y. K. (2013). Successful treatment of pediatric nail psoriasis with periodic pustular eruption using topical indigo naturalis oil extract. Pediatric dermatology, 30(1), 117-119.
[Wiley Online Library]
[15] Lin, Y. K. (2011). Indigo naturalis oil extract drops in the treatment of moderate to severe nail psoriasis: a small case series. Archives of dermatology, 147(5), 627-629.
[JAMA Network]
[16] Lin, Y. K., Chang, Y. C., Hui, R. C. Y., See, L. C., Chang, C. J., Yang, C. H., & Huang, Y. H. (2015). A Chinese herb, indigo naturalis, extracted in oil (Lindioil) used topically to treat psoriatic nails: a randomized clinical trial. Jama Dermatology, 151(6), 672-674.
[JAMA Network]