Anti-inflammatory activity
Inflammation is well known to trigger the production of melanin. This is why anti-inflammatory ingredients are often included in skin lighting products. A. capillaris displays anti-inflammatory activity and has shown some antioxidant activity.
In 2018, Lee et al. confirmed the therapeutic potential of A. capillaris extract to treat psoriasis in HaCaT cells and imiquimod-induced psoriasis-like mouse models. In the murine models, those treated with the ethanol extract of A. capillaris had a significantly lower Psoriasis Area and Severity Index score than that of the mice not given the topical application of the botanical. Epidermal thickness was noted to be significantly lower compared with the mice not treated with A. capillaris.9 Further studies in mice by the same team later that year supported the use of a cream formulation containing A. capillaris that they developed to treat psoriasis, warranting new investigations in human skin.10
Yeo et al. reported, earlier in 2018, on other anti-inflammatory activity of the herb, finding that the aqueous extract from A. capillaris blocked acute gastric mucosal injury by hindering reactive oxygen species and nuclear factor kappa B. They added that A. capillaris maintains oxidant/antioxidant homeostasis and displays potential as a nutraceutical agent for treating gastric ulcers and gastritis.5
In 2011, Kwon et al. studied the 5-lipoxygenase inhibitory action of a 70% ethanol extract of aerial parts of A. capillaris. They identified esculetin and quercetin as strong inhibitors of 5-lipoxygenase. The botanical agent, and esculetin in particular, robustly suppressed arachidonic acid-induced ear edema in mice as well as delayed-type hypersensitivity reactions. Further, A. capillaris potently blocked 5-lipoxygenase-catalyzed leukotriene synthesis by ionophore-induced rat basophilic leukemia-1 cells. The researchers concluded that their findings may partially account for the use of A. capillaris as a traditional medical treatment for cutaneous inflammatory conditions.2
Atopic dermatitis and A. capillaris
In 2014, Ha et al. used in vitro and in vivo systems to assess the anti-inflammatory effects of A. capillaris as well as its activity against atopic dermatitis. The in vitro studies revealed that A. capillaris hampered NO and cellular histamine synthesis. In Nc/Nga mice sensitized by Dermatophagoides farinae, dermatitis scores as well as hemorrhage, hypertrophy, and hyperkeratosis of the epidermis in the dorsal skin and ear all declined after the topical application of A. capillaris. Plasma levels of histamine and IgE also significantly decreased after treatment with A. capillaris. The investigators concluded that further study of A. capillaris is warranted as a potential therapeutic option for atopic dermatitis.11
Summary
Many botanical ingredients from Asia are making their way into skin care products in the USA. A. capillaris extract is an example and may have utility in treating hyperpigmentation-associated skin issues such as melasma. Its inhibitory effects on both inflammation and melanin production in addition to possible antioxidant activity make it an interesting compound worthy of more scrutiny.
Dr. Baumann is a private practice dermatologist, researcher, author, and entrepreneur who practices in Miami. She founded the Cosmetic Dermatology Center at the University of Miami in 1997. Dr. Baumann has written two textbooks and a New York Times Best Sellers book for consumers. Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Galderma, Revance, Evolus, and Burt’s Bees. She is the CEO of Skin Type Solutions Inc., a company that independently tests skin care products and makes recommendations to physicians on which skin care technologies are best. Write to her at dermnews@mdedge.com.
References
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2. Kwon OS et al. Arch Pharm Res. 2011 Sep;34(9):1561-9.
3. Hsueh TP et al. Biomedicines. 2021 Oct 8;9(10):1412.
4. Dolinska MB et al. Int J Mol Sci. 2020 Jan 3;21(1):331.
5. Yeo D et al. Biomed Pharmacother. 2018 Mar;99:681-7.
6. Kim YS et al. J Food Sci. 2008 Jan;73(1):T16-20.
7. Kim MJ et al. Mol Med Rep. 2022 Apr;25(4):113.
8. Tabassum N et al. Evid Based Complement Alternat Med. 2016;2016:7823541.
9. Lee SY et al. Phytother Res. 2018 May;32(5):923-2.
10. Lee SY et al. Evid Based Complement Alternat Med. 2018 Aug 19;2018:3610494.
11. Ha H et al. BMC Complement Altern Med. 2014 Mar 14;14:100.