Pro- and prebiotics on the skin?
An interview with Cath O’Neill
Cath is coming from the skin research area, being an expert on skin health. During the last years her research focussed on the skins microbiome. With her company SkinBioTherapeutics, Cath translated her research from the University of Manchester into the SkinBiotix® platform. SkinBioTherapeutics is targeting three specific skin healthcare sectors: cosmetics, infection control and eczema.
The SkinBiotix® platform is based on discoveries made with lysates derived from bacteria such as Lactobacillus and Bifidobacterium.
I met Cath on the 5thMicrobiome R&D and Business Collaboration Forum in Rotterdam and asked her about the effects of pro- and prebiotics on the skins microbiome:
How do probiotics affect the skins microbiome?
“I don’t think you can change the skins microbiome by putting on probiotics from the gut, but you can certainly change the skins physiology. Lactobacilli are quite anaerobic, so they are probably not going to grow well on the skin. Nevertheless, even as a dead preparation, specific strains of lactobacilli have some remarkable effects on skin”
What about prebiotics for the skin?
“The well-known gut Prebiotics like FOS are not prebiotic on the skin because the skin’s microbiome doesn’t have the enzymatic machinery to digest these prebiotics. Much more research is needed to identify compounds that promote the growth of beneficial bacteria in skins microbiome”
SkinBioTherapeutics is applying dead bacteria on the skin. How is the principle working?
“We use lysates of microorganisms, to me it’s a little bit like vaccines. Vaccines are dead or attenuated bacteria which still elicit an immune response. We know the proteins within the bacterial extracts because we’ve analysed them by MASS-Spec and we know which effects they elicit on the skin. We screened loads of different strains for efficacy and we´ve done a lot of science in vitro.”
Indeed, the claims of SkinBio Therapeutics are scientifically substantiated. In four peer reviewed publications Cath O’Neill and co-workers describe their work on keratinocyte (predominant cell type in the epidermis, the outermost layer of the skin) models:
1. Improvement of the barrier effect of skin models
In a cell culture of keratinocytes the formation of so called ‘tight junctions’, which seal the space between the cells, was investigated in the presence of bacterial lysates of Bifidobacterium longum and different Lactobacillus strains. Except for L. fermentum all strains investigated enhanced the tight-junction barrier within 24h. Overall, B. longum and L. rhamnosus GG were most efficacious with a dose dependent effect over 4 days. These data show that effects of probiotics/ probiotic lysates on the skins tight-junctions are strongly strain-dependent!
2. Improved skin repair
In another study on keratinocytes, the effect of different Lactobacillus lysates was investigated in a scratch assay. In this assay, a monolayer of keratinocytes was scratched and then incubated with the respective bacterial lysate. Re-epithelialization of the scratches was monitored and compared to an untreated control. While L. rhamnosus GG and L. reuteri significantly increased the rate of re-epithelialization, L. rhamnosus GG lysate was most efficacious triggering increased proliferation and migration rates of the cells.
3. Reduced bacterial load
In two different studies, the inhibiting effect of different Lactobacillus lysates on Staphylococcus aureus infections was investigated on a keratinocyte monolayer. S. aureus is the overabundant infectious agent in atopic dermatitis patients. These studies showed that certain bacterial species were able to prevent S. aureus infection due to growth inhibition and reduction of bacterial adherence (LGG) and competitive exclusion. However, this protection of the keratinocytes against S. aureus infection was only observed when the probiotic lysates were added before or simultaneously with S. aureus, thus suggesting a prophylactic use of probiotics against infection.
All these studies performed by Cath and her colleagues show that probiotics which are normally used for food may also be beneficial for skin health. However, the observed effects are very variable between bacterial species, thus a detailed scientific evaluation of the used bacterial strain(s) is obligatory.
SkinBio Therapeutics is planning clinical studies on humans for their three indications Scientific Skin Care, Infection control and Eczema.
We are very excited about the results!
Thank you Cath for the interview and looking forward to the next interview on the results of the clinical studies!