Research from the University of Antwerp, recently published in Cell Reports Medicine, has indicated selected probiotic strains could mediate the skin microbiome to reduce acne lesions.
Acne on the face is often treated with topical antibiotics, which tend to be used for an extended period of time and contribute to the serious problem of antibiotic resistance. The researchers at Antwerp are investigating an alternative approach using lactobacilli strains, typically associated with the gut microbiome, to alter the collection of bacteria and other microorganisms residing on the skin. Although the ecosystem on the skin may play a significant role in causing acne-causing inflammation, this system has proven difficult to alter.
Prof Sarah Lebeer, who led the research, said: “Lactobacilli are well-documented safe and beneficial bacteria that produce lactic acid as a broad-acting antimicrobial molecule that can inhibit the growth and activity of a wide array of competing bacteria. They can also often reduce inflammation in different conditions. Therefore, we suspected they could work for this purpose even though they’re not highly abundant on the skin.”
The researchers selected the three strains of lactobacilli—Lacticaseibacillus rhamnosus GG, L. plantarum WCFS1, and Lactiplantibacillus pentosus KCA1—employing genome and functional screening to evaluate the probiotics’ robustness, safety and predicted immune system interactions. They also developed a cream with micro-capsules containing the microorganisms for topical application.
In both a pilot study and a randomised, placebo-controlled trial, the researchers asked people with mild-to-moderate acne to apply the cream on a daily basis. The intervention successfully reduced inflammatory lesions on subjects’ skin. It also modulated the cutaneous microbiome, in part by reducing the relative abundance of staphylococci, which are bacteria thought to perpetuate acne.
Even after individuals discontinued application of the cream, the reduction in acne symptoms persisted for several weeks, leading the researchers to believe the trio of bacteria act, at least partially, by modulating the immune system. Lebeer says more research is needed on the mode of action of these bacteria for the treatment of acne.
Lebeer is a board member of ISAPP (the International Scientific Association for Probiotics and Prebiotics), which published the scientific consensus definition of probiotics in 2014.
Mary Ellen Sanders, ISAPP’s Executive Science Officer, says, “The intention of the probiotic definition was to encompass probiotics not just for the gut, but for many other applications, including the skin. This research elegantly shows the progress being made in these non-gut applications.”
