Cosmeceutical Critique

Snail mucus in skin care

Publish date: June 15, 2020

Although it is not glamorous, snail mucus is a popular ingredient in skin care products. Its use dates back to ancient Greece, where Hippocrates reportedly applied crushed snails to treat skin inflammations.¹ The modern consideration of using snail secretions in skin care arose serendipitously in the 1990s when Chilean farmers observed accelerated healing of their skin lesions without scarring after handling snails.¹

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Today, snail mucin is among the increasingly wide array of bioactive ingredients undergoing scientific validation and inclusion in the burgeoning Korean cosmeceutical market.^2,3 In fact, a variety of Korean cosmeceuticals incorporate the mucus derived from Achatina fulica (African giant land snail) and Cryptomphalus (Helix) aspersa (common brown garden snail) based on their demonstrated antimicrobial and skin regenerative activity.^1,3,4 The antioxidant properties also attributed to snail mucus are thought to originate in constituents such as glycosaminoglycans, as well as growth factors, and may justify the use of these ingredients in novel cosmeceuticals.⁵ The focus of this discussion is recent research into the novel use of this animal-derived product for dermatologic purposes.

Antioxidant activity, skin rejuvenation, and wound healing

In 2008, Brieva et al. reported on a screen for natural products yielding a molecular basis for the secretions of the mollusk Cryptomphalus aspersa, which displays skin-regenerative activity. Specifically, they found that the secretion exerts antioxidant superoxide dismutase and glutathione S-transferase, and spurred fibroblast proliferation and extracellular matrix assembly while regulating metalloproteinase function. The researchers concluded that such activities may support wound regeneration.⁵

Four years later, Cruz et al. found that secretions of C. aspersa promote in vitro cell proliferation and migration by localizing beta-catenin to the nuclei of human fibroblasts and keratinocytes, augment phosphorylated focal adhesion kinase, and thereby enhance cell survival. The investigators concluded that snail secretions may therefore impart regenerative and wound healing activity.3,6

Antimicrobial properties

In 2015, Pitt et al. investigated the antimicrobial properties of the mucus of the brown garden snail C. or H. aspersa, which had a reputation for exhibiting skin regeneration capabilities. Their results revealed that snail mucus displayed a strong antibacterial effect against multiple strains of Pseudomonas aeruginosa and a weak effect against Staphylococcus aureus.⁴

Indications for the use of snail mucin

Radiation-induced dermatitis and burns represented the first indication for the initial use of snail mucin as a cutaneous therapy.⁷ Experimental and clinical studies have since been performed to assess its applicability to treat acute radiation dermatitis, atopic dermatitis, partial-thickness burns, and photoaging.^8-11

A 2017 in vitro investigation by Ellijimi et al. revealed that snail mucin displayed antimelanogenic and antitumoral activity against human melanoma cells, suggesting another possible application of this product.¹²

Human studies on photoaging

In a 2009 study by Tsoutsos et al. of an open, moist burn management protocol in deep partial-thickness facial burns, a cream containing H. aspersa secretions was identified to be an effective treatment option. For 14 days or until full epithelialization, 27 adult patients were treated with snail extract cream twice daily. Comparisons were made to 16 patients treated with moist exposure burn ointment. Visual analog scale pain scores were significantly lower in the group that received the H. aspersa cream, compared with the moist exposure burn group. The researchers concluded that the H. aspersa cream is a safe, effective, and natural option for treating partial-thickness burns in adults that acts by facilitating debris removal and accelerating reepithelialization.¹⁰

Also that year, Tribo-Boixareu et al. treated 15 patients with chronic photodamage with secretions of C. aspersa over a 3-month period, yielding significant amelioration in the clinical and histologic markers of photoaging.¹¹

Four years later, a double-blind, split-face, randomized, controlled clinical study conducted by Fabi et al. over 12 weeks demonstrated that the topical application of an antiphotoaging formulation containing C. aspersa mucus diminished periocular and fine facial rhytides and enhanced skin texture within 8 weeks of treatment initiation.⁷

Snail eggs and photoaging

In 2015, Espada et al. determined in vitro that an extract derived from C. aspersa eggs could reorganize the cytoskeleton of keratinocytes and fibroblasts, as well as trigger the synthesis of the extracellular proteins collagen and fibronectin. They also found that gene expression declined in age-related genes including p53 and b-Gal. The researchers concluded that C. aspersa egg extract has the potential to reduce the signs of photoaging.^3,13

Dr. Leslie S. Baumann

Antiaging cosmeceuticals

In a 2017 assessment of the antiaging and skin-whitening activity of the nine most popular ingredients in the South Korean skin care product market, Quay et al. considered industry profit data from Euromonitor and conducted a comprehensive literature search. They identified licorice, niacinamide, green tea, soy, beta-glucan, snail mucus, ginkgo biloba, ginseng, and pomegranate as the nine most popular ingredients, with the first four associated with the most supportive data. They found a paucity of cogent evidence on the use of the other ingredients in antiaging and skin-whitening formulations.¹⁴

Conclusion

The use of snail mucin to treat skin dates back at least to the time of Hippocrates. Recent research suggests reasons for optimism, and further investigation, as this ingredient appears to have potential across various cutaneous conditions. As is often the case, though, much more research is necessary to ascertain what enduring benefits may be derived from the use of snail mucin. Nevertheless, this product has been available on the market for the last 20 years and is associated with anecdotal reports of efficacy.

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 wrote two textbooks: “Cosmetic Dermatology: Principles and Practice” (New York: McGraw-Hill, 2002), and “Cosmeceuticals and Cosmetic Ingredients” (New York: McGraw-Hill, 2014), and a New York Times Best Sellers book for consumers, “The Skin Type Solution” (New York: Bantam Dell, 2006). Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Evolus, Galderma, and Revance. She is the founder and CEO of Skin Type Solutions Franchise Systems LLC. Write to her at dermnews@mdedge.com. She has no relevant disclosures.