The causes of acne could be more than skin deep—maybe gut deep, according a new investigative study performed in China.
The recent study detailed in the Journal of Investigative Dermatology reports that patients afflicted with acne have distinct differences in the ratios of their gut microbiome compared to patients without acne. These differences may be reflected in the skin microbiome.
“There is clearly a change in the diversity and population of bacteria in those who get acne,” said Dr. Adam Friedman, an associate professor of dermatology at George Washington University who was not affiliated with the study. “It’s not like bacteria are bad or good, it’s that they’re good when everyone is where they’re supposed to be in the right concentration, that communities are in harmony with one another.”
In those with acne, “there’s a decrease in diversity among organisms. There are certain types of bacteria in particular that are implicated in clinical disease,” Friedman said, including P. acnes and Staphylococcus, the proportions of which vary before, during, and after an infection.
Both Staphylococcus and P. acnes have the ability to inhibit the growth of the other, leading to a sort of tug of war that can contain or cause acne breakouts.
Years ago, Friedman said, P. acnes was considered a “bystander” when it came to acne infections because no one could figure out its role in the infection. It was simply always present during acne breakouts, giving the bacteria its name. Thanks to the recent advances in research, dermatologists and skin researchers now know it’s a main player.
The study of the body’s bacterial harmony and its disruption was enabled by a technique known as 16S RNA sequencing, which is now heavily used in human microbiome research.
Before 16S RNA sequencing, “we weren’t even able to study this,” Friedman said, “A lot of these organisms [in the human skin and gut microbiomes], you can’t even culture.”
Though the sequencing technique was available decades ago, it has only been recently applied to microbiome research, said Nora Richter, a graduate student at Brown University who uses 16S RNA sequencing in her research.
The sequencing technique is “gaining more momentum because sequencing methods are becoming cheaper,” Richter said. And cheaper costs mean more data for researchers to analyze, furthering the science of the skin.
The sequencing method, she said, is used to identify the different bacterial species as well as how closely related those species are in a particular environment. In the case of recent acne research, the environments of the skin and gut.
Though the science behind the pathology of acne is advancing, current acne treatment methods have yet to change. Current common acne treatments involve oral antibiotics or over-the-counter salicylic acid or benzoyl peroxide. For more serious cases, patients may incorporate isotretinoin into their routines, formerly known as Accutane.
These treatments indiscriminately inhibit and prevent bacterial growth and don’t always lead to the restoration of healthy bacterial proportions in those who suffer from chronic acne.
Marie-Ange Dagnelie, a graduate student at the University of Nantes, studies the microbiology of the skin. She thinks the recent advances in skin microbiome research could be used to develop new therapeutic approaches for treating acne.
Understanding the connections between different skin bacteria, she believes, can influence future acne treatments. Dagnelie imagines a therapeutic approach that is able to restore healthy proportions of skin bacteria by using bacteria themselves.
This approach is similar to fecal transplants, where doctors transplant gut flora from healthy patients to those suffering from gastrointestinal infections. Such treatments have restored the healthy balance of bacterial populations.
“I’m really convinced that in future years this will be a new treatment, especially in acne,” she said.