1 This column discusses some of the emerging data in this novel area of medical and dermatologic research. For more detailed information, a on the therapeutic potential of peptides in animal venom was published in 2003 (Nat Rev Drug Discov. 2003 Oct;2:790-802).
The potential of peptides found in snake venom
Snake venom is known to contain carbohydrates, nucleosides, amino acids, and lipids, as well as enzymatic and nonenzymatic proteins and peptides, with proteins and peptides comprising the primary components.2
There are many different types of peptides in snake venom. The peptides and the small proteins found in snake venoms are known to confer a wide range of biologic activities, including antimicrobial, antihypertensive, analgesic, antitumor, and analgesic, in addition to several others. These peptides have been included in antiaging skin care products.3Pennington et al. have observed that venom-derived peptides appear to have potential as effective therapeutic agents in cosmetic formulations.4 In particular, Waglerin peptides appear to act with a Botox-like paralyzing effect and purportedly diminish skin wrinkles.5
Issues with efficacy of snake venom in skin care products
As with many skin care ingredients, what is seen in cell cultures or a laboratory setting may not translate to real life use. Shelf life, issues during manufacturing, interaction with other ingredients in the product, interactions with other products in the regimen, exposure to air and light, and difficulty of penetration can all affect efficacy. With snake venom in particular, stability and penetration make the efficacy in skin care products questionable.
The problem with many peptides in skin care products is that they are usually larger than 500 Dalton and, therefore, cannot penetrate into the skin. Bos et al. described the “500 Dalton rule” in 2000.6 Regardless of these issues, there are several publications looking at snake venom that will be discussed here.
Antimicrobial and wound healing activity
In 2011, Samy et al. found that phospholipase A2 purified from crotalid snake venom expressed antibacterial activity in vitro against various clinical human pathogens. The investigators synthesized peptides based on the sequence homology and ascertained that the synthetic peptides exhibited potent microbicidal properties against Gram-negative and Gram-positive (Staphylococcus aureus) bacteria with diminished toxicity against normal human cells. Subsequently, the investigators used a BALB/c mouse model to show that peptide-treated animals displayed accelerated healing of full-thickness skin wounds, with increased re-epithelialization, collagen production, and angiogenesis. They concluded that the protein/peptide complex developed from snake venoms was effective at fostering wound healing.7
In that same year, Samy et al. showed in vivo that the snake venom phospholipase A₂ (svPLA₂) proteins from Viperidae and Elapidae snakes activated innate immunity in the animals tested, providing protection against skin infection caused by S. aureus. In vitro experiments also revealed that svPLA₂ proteins dose dependently exerted bacteriostatic and bactericidal effects on S. aureus.8 In 2015, Al-Asmari et al. comparatively assessed the venoms of two cobras,four vipers, a standard antibiotic, and an antimycotic as antimicrobial agents. The methicillin resistant Staphylococcus aureus bacterium was the most susceptible, followed by Gram-positive S. aureus, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa. While the antibiotic vancomycin was more effective against P. aeruginosa, the venoms more efficiently suppressed the resistant bacteria. The snake venoms had minimal effect on the fungus Candida albicans. The investigators concluded that the snake venoms exhibited antibacterial activity comparable to antibiotics and were more efficient in tackling resistant bacteria.9 In a review of animal venoms in 2017, Samy et al. reported that snake venom–derived synthetic peptide/snake cathelicidin exhibits robust antimicrobial and wound healing capacity, despite its instability and risk, and presents as a possible new treatment for S. aureus infections. They indicated that antimicrobial peptides derived from various animal venoms, including snakes, spiders, and scorpions, are in early experimental and preclinical development stages, and these cysteine-rich substances share hydrophobic alpha-helices or beta-sheets that yield lethal pores and membrane-impairing results on bacteria.10