We’re back with the second in our quarterly review series that keeps you enlightened on the latest research, industry developments and news around the microbiome.
This time, we summarize the ‘Out of your skin’ article published in the April edition of Nature Biotechnology then take a dive into some highlights in microbiome research – on the skin and beyond – from the last three months.
Out of your skin
Published in Nature Biotechnology, this read provides a fascinating overview of the latest research into skin microbes and the secrets that we are beginning to discover in relation to health and disease management. We have summarized our key takeaways below:
- As scientific technology continues to develop, researchers are able to utilise and capture genetic material from smaller biological samples, enabling differentiation between microbial species and, increasingly, strains
- Gut microbiome research is more advanced than studies on the skin microbiome, which requires new approaches to develop therapies due to the increased structural complexity of the skin and relatively small microbial concentrations
- However, this doesn’t mean that skin microbiome treatments need to be more complex. In fact, as the majority of skin conditions derive from the breakdown of the skin barrier and are associated with skin colonization of pathogens, such as S. aureus, this provides a clear target for treatments to aim for
- More specifically, the ‘Out of your skin’ review looks at how biotech companies are making moves to use the skin microbiome to treat skin conditions, whether that be using commensal (healthy) bacteria already present in the skin microbiome or engineering bacteria to meet their needs. We have outlined a few interesting examples of each below…
Using commensal (healthy) bacteria to treat skin conditions:
- MatriSys Biosciences has taken to interfering with the growth of pathogenic S. aureus colonies to treat atopic dermatitis (eczema) using a healthy bacterium – S. hominis – to suppress its growth
- In the search for a new acne treatment that does not irritate or dry the skin as those currently on the market tend to do, Naked Biome has identified and applied use of a ‘healthy’ strain of C. acnes that is less inflammatory than strains associated with acne, and therefore has potential to reduce acne symptoms
- Also targeting acne, S-Biomedic have taken to look at molecules produced by C. acnes rather than the bacterium itself. Having shown that modulation of the skin microbiome can be done using healthy bacterial samples (see more on this here), the company is now preparing a product for acne made from a strain that produces lower levels of an enzyme linked to the development of acne
- DermBiont has isolated a bacterium found on amphibian skin and in low levels on human skin that has anti-fungal properties. The company is now exploiting its anti-fungal properties in a trial to treat Athlete’s Foot
Engineering bacteria to treat skin conditions by enhancing beneficial capabilities:
- Xycrobe Therapeutics has engineered strains of C. acnes to secrete an anti-inflammatory molecule – a reduction in which is often associated with people with acne and psoriasis
- Taking a different approach, Azitra has produced a strain of commensal bacteria S. epidermis, the growth of which they are able to control so as to outcompete pathogenic S. aureus. As well as the cause for conditions such as eczema, colonization of S. aureus is associated with a form of cancer therapy thus making patients more vulnerable to rashes
Interestingly, it seems that many companies in the skin microbiome field are creating their products as consumer health products rather than as therapeutics. This is due to the much faster path to commercialization as, although they are regulated, cosmetics do not have to be tested for efficacy. While not a single therapeutic product, targeting either the gut or skin microbiome, has yet won regulatory approval, we are seeing microbiome-based cosmetics widely available on the market.
Companies often develop therapeutics and cosmetics alongside each other or in succession. Indeed, it is common for the same bacteria to be components in products for both markets but in different doses depending if for therapeutic or cosmetic use. Higher doses are used in therapeutic applications so as to engraft better into skin and persist for longer to exert its beneficial effects.
Available online (subscription required): https://www.nature.com/articles/s41587-020-0473-8#citeas
In addition to the long-read above, there has been a range of recent research published on the skin microbiome in space, the link to stress and the gut microbiome and also the impact vaping has on the oral microbiome. Scroll on to find out more…
Exchanging microbes in space
As part of NASA’s Human Research Program, a multi-year program investigated the impact of long-term space travel on the microbiome of astronauts – specifically the effect of long-duration stays on the International Space Station (ISS) – and how this might affect their microbiome and health. They looked at the gut, nasal, tongue, skin, saliva and blood and results were shared in mid-2019.
Given the uniquely isolated and sterile environment of the space station, it was expected that reduced microbial diversity would be found. However, much to their surprise, the gut microbiomes of the astronauts became more diverse (a benefit for human health) despite the lack of exposure to new bacteria. The impact on the microbial diversity of the skin was less clear than the gut with a mixture of increased and decreased diversity discovered in different individuals. One consistent observation in the skin was a notable decrease in specific bacteria associated with protection from hypersensitive skin reactions. This provides an explanation for the higher incidence of skin rashes found in astronauts.
More recently, data released shows that this microbial exchange between astronaut and environment isn’t a one-way street. Indeed, through Microbial Tracking, researchers have found that the microbiome of the ISS itself reflects that of the astronauts’ skin – with 55% of the surface microbiome attributed to that of one astronaut investigated.
The prevalence of microbes derived from a new crew member provides a sort of calendar, enabling researchers to tell when a person arrives or departs based on the ISS’s microbiome alone.
There’s much more to be explored but these findings provide a glimpse into how space travel affects human health.
What’s going on beyond the skin microbiome? We love talking about all things skin and the more than 1,000 species of bacteria that inhabit it yet this makes up only 0.46% of our human microbiome so there is a lot more out there that is being explored…
Stress and the gut microbiome
We know that psychological stresses can wreak havoc on our bodies, and this is more relevant now than ever. The ongoing COVID-19 pandemic is causing elevated levels of stress in the global population with raised concerns around health, relationships, isolation, and both short- and long-term financial standing.
As such, more and more articles are being published with tips to help us take care of our minds and bodies right now. Take this one published on Gutxy which provides some insight into how we can help our brains through our guts!
Microbiome research is increasingly linking stress with the gut microbiome via the gut-brain axis. In fact, one researcher found that stress-driven changes to the gut microbiome was reflected in disruption to the body’s immune response – including to COVID-19.
Vaping and the oral microbiome
Vaping – or use of e-cigarettes – is a trend that has becoming increasingly popular since the 2000s. While smoking has been on a downward trajectory for some time, the pattern of vape use is very much the opposite. The number of vape users worldwide leapt from 7 million in 2011 to 41 million in 2018 and Euromonitor estimates this figure will have climbed to nearly 55 million by next year.
There have been contradictory views surrounding the safety of vapes as an alternative to cigarette smoking. A 2015 independent study suggested e-cigarettes are 95% less harmful than tobacco, but there is growing evidence to the contrary; a recent longer term study suggested they do more harm than previously thought.
But how does vaping affect the microbiome?
Scientists in the US looked into just that by comparing the oral microbiomes of non-smokers, cigarette smokers and e-cigarette users. Looking at individuals who used e-cigarettes, they found that their oral microbiomes resembled those of patients with periodontitis, a gum disease associated with other severe conditions such as diabetes and coronary heart disease. The results, therefore, indicate that e-cigarettes negatively influence the oral microbiome with potential to lead to a variety of related pathologies. The researchers also showed that the damaging effects to the microbiome were not due to the presence of nicotine.