Despite how common acne is and how long it has been around—the earliest mention of acne can be traced back to the Ebers Papyrus dating back to before 3,000 BC—the condition is still poorly understood. This uncertainty is reflected in advice on how to tackle acne, with facial treatments running the gamut from honey to mud.
A popular theory is that acne is caused by an imbalance in the microbial population inhabiting the skin. However, scientific evidence for this theory is weak, said Thomas Dawson, senior principal investigator at the Skin Research Institute of Singapore (SRIS).
“Currently, the role of the skin microbial community in acne remains unknown,” he said. “Significant ‘lore’ implicates skin microbiology in acne, and hence many treatments contain antimicrobials. The assumption that microbial dysbiosis is the cause of acne means research is focused on microbes, while it remains unclear if this is a correct choice.”
One challenge in studying microbial dysbiosis in acne lies in the sampling of the correct skin compartment, which influences the kind of skin microbiota isolated. “Most studies which have measured microbes in acne have sampled from the skin surface. But it is highly unlikely surface microbes are involved, as the initiation of the lesion must occur deeper in the skin, where the cells are alive and able to be involved in inflammation,” Dawson pointed out.
Another challenge is rooted in the complexity of the skin microbiota, which comprises different bacteria and fungi, as well as bacteriophages (viruses that infect bacteria). Knowing which ones are responsible for acne and which are mere bystanders is crucial to identifying potential therapeutic targets. However, this obstacle could be overcome by isolating single variables and changing them one at a time, Dawson said.
“This means performing clinical trials where acne patients are treated with specific anti-microbial and non-antimicrobial actives, and then evaluating the effect on the acne as well as on the microbial community,” he continued.
Several types of acne treatments—such as isotretinoin, antimicrobials and hormonal pills—already exist, but the prevailing uncertainty over the cause of acne means that identifying the best course of treatment remains an issue. Dawson also highlighted the importance of seeking alternative forms of treatment, given the risks associated with current therapies such as retinoid treatments, which have unwanted and dangerous side effects.
“We are trying to better define acne etiology and design new, more effective treatments with fewer side effects by examining and targeting different biology than has been used in the past,” he said.
The A*STAR-affiliated researchers contributing to this research are from the Skin Research Institute of Singapore (SRIS).