J. Cosmet. Sci., 63, 385–395 (November/December 2012) 385 Physiological effect of a probiotic on skin NEELAM MUIZZUDDIN, WANDA MAHER, MICHAEL SULLIVAN, STEVEN SCHNITTGER, and THOMAS MAMMONE, Estee Lauder Companies, New York, NY 10153. Accepted for publication April 13, 2012. Synopsis Introduction and objective: Normal human skin can produce a range of antimicrobial chemicals that play an important part in eliminating potential cutaneous pathogens. Lactobacillus plantarum is a gram-positive bac- teria that produces antimicrobial peptides, which when applied to the skin can act like an anti-infl ammatory as well as enhance the antimicrobial properties of the skin. Clinical studies were conducted to determine the effect of lactobacillus extract on improvement of skin barrier and reduction of erythema from chemical irri- tant, skin microfl ora, and acne. Results show that lactobacillus extract was effective in reducing skin ery- thema, repairing skin barrier, and reducing skin microfl ora, thereby exhibiting an effective reduction in acne lesion size and erythema at 5%, but not at 1%.Conclusion: Based on the results of these studies, lactobacillus extract (5%) can be used to treat mild acne lesions. INTRODUCTION The concept of probiotics likely dates back to 1908, when Nobel Prize winner Eli Metchnikoff suggested that the long life of Bulgarian peasants resulted from their con- sumption of fermented milk products (1). The term “probiotic” was fi rst used in 1965 by Lilly and Stillwell for describing the substances secreted by one organism, which stimu- late the growth of another (2). Marteau et al. in 2002 (3) defi ned them as “microbial preparations or components of microbial cells that have a benefi cial effect on health and well being” (2,3). Probiotics from Lactobacillus cultures are well recognized as possessing certain health benefi ts, such as antimicrobial and immune-stimulating properties. A recent study (4) showed that prenatal administration of Lactobacillus GG reduced the risk of children de- veloping eczema. Lactobacillus cultures have also been reported to possess antimicrobial activity against pathogenic bacteria such as Staphylococcus aureus (5). Normal human skin is remarkably resistant to infection from a myriad of microorganisms that routinely colonize its surface. In addition to the role of skin as a mechanical barrier, Address all correspondence to Neelam Muizzuddin at nmuizzud@estee.com.

JOURNAL OF COSMETIC SCIENCE 386 it has long been recognized that skin and other epithelia can produce a range of antimicrobial peptides that play an important part in eliminating potential cutaneous pathogens (6,7). Antimicrobial peptides are induced in keratinocytes of the skin via the binding of bacte- rial lipopolysaccharides, beta glucans, some mannose-containing carbohydrates, peptido- glycans or bacterial DNA to “pattern recognition” receptors, or the toll-like receptors. Heat-killed bacteria or fungi alone can provoke the transcription of antimicrobial pep- tides. Lactobacillus and other types of lactic acid bacteria have been reported to produce specifi c antimicrobial peptides known as bacterocins (8) that possess broad-spectrum an- timicrobial activity against gram-negative and gram-positive bacteria (9). Oral administration of probiotics has been shown to be effective in improving skin barrier functions (10). Impaired skin barrier function is invariably caused by decreased amounts of ceramides that may be responsible for comedone formation, since barrier dysfunction is accompanied by hyperkeratosis of the follicular epithelium (11). Since microbial agents, impaired barrier, and infl ammation play an important role in acne, we considered observing the effect of a probiotic on acne. Acne vulgaris is a com- plex, chronic, and common skin disorder of pilosebaceous units (12). The major patho- genic factors involved are ductal hyperkeratinization, obstruction of sebaceous follicles resulting from abnormal keratinization of the infundibular epithelium, stimulation of sebaceous gland secretion by androgens, and microbial colonization of pilosebaceous units by Propionibacterium acnes. Both viable and non-viable P. acnes have been shown to induce an immunostimulatory effect that activates an infl ammatory response (13). The infl ammatory stage of acne vulgaris is usually of greatest concern to the patient. A num- ber of morphologically different infl ammatory lesions may form that can be painful and unsightly and can lead to scarring. Infl ammatory acne and acne scarring can have signifi - cant psychological effects on the patient, including depression, anxiety, and poor self- image. The onset of non-infl ammatory lesions is understood as the consequence of follicular keratinocytes failing to differentiate, thus producing hypergranulosis, resulting in the formation of microcomedones (12). Acne is commonly treated with antibiotics, bactericidals, retinoids, and so on, however, most of such treatments come with side effects. In this study, we addressed alleviation of three aspects of acne, namely skin microfl ora, barrier strength, and infl ammation using a probiotic: lactobacillus extract. MATERIALS AND METHODS The test material was the probiotic lactobacillus extract (14). The Lactobacillus ferment was prepared in MRS broth (Neogen Corporation, Lansing, MI) inside a 1000-L fermen- ter sterilized for 20 min at 121°C to insure sterility. The vessel was cooled to 37°C and nitrogen was pumped into the vessel until the total dissolved oxygen was down to zero in order to ensure anaerobic conditions for the growth of Lactobacillus plantarum. The vessel was inoculated with 10 L (or 1% of total volume) of L. plantarum prepared in the same MRS media broth and same conditions as the fi nal 1000-L vessel. The organism was al- lowed to grow in the vessel for 18–24 h after which the ferment was passed through a heat exchanger to lyse most of the cells. The ferment was then fi ltered fi rst through a 0.45-μm fi lter, and fi nally through a 0.22-μm fi lter to produce the fi nal broth (14).