MAR 11, 2019 12:02 PM PDT

How Different Strains of Bacteria Impact Acne

WRITTEN BY: Carmen Leitch

The microbe Propionibacterium acnes has long been thought to be the cause of acne, but it can be found on everyone’s skin. While up to eighty percent of people may experience acne to some degree, not everyone gets it. Now researchers may have an explanation for these observations - not all strains of P. Acnes are the same; some are found in abundance in acne lesions while other strains are never found there. Researchers have explored how different strains of the bacterium impact skin by using a new research model for acne. In a first, scientists have been able to create a mouse model for acne by adding a chemical secreted in abundance by adolescent skin - sebum. The work has been reported in JCI Insight.

Image credit: Pixabay

"Since we know exactly which genes differ between these strains, next we can pinpoint exactly what it is about the acne-associated strains that allows them to cause skin lesions," said George Y. Liu, MD, Ph.D., a professor and chief of the Division of Pediatric Infectious Diseases at UC San Diego School of Medicine, formerly of Cedars-Sinai. "And that information will help us develop new therapies that specifically block those acne-promoting factors, or tip the balance of a person's skin chemistry in favor of the healthy strains."

In this work, mice were inoculated with P. acnes. The mice got minimal lesions afterward unless they had also received a synthetic sebum made from four ingredients (wax, triglyceride, fatty acid, and a sterol precursor called squalene) on a daily basis. By itself, the sebum had no effect. When strains of P. acnes that have been linked to human acne lesions were applied, the mice got what looked like human acne. Skin inflammation and inflammatory cytokine levels both increased. If P. acnes strains that have been linked to health were used, the lesions were far less severe.

Mouse skin treated with synthetic human sebum, administered with strains of either acne-associated P. acnes (left) or health-associated P. acnes (right), and viewed under a microscope./ Credit: UC San Diego Health

"When we started working with these bacteria and checked out the animal models others have been using over the years, we thought 'we've got to come up with something better than this,'" Liu said. "Acne typically occurs when a person hits their teenage years ...What's the difference between a child's skin and a teenager's skin? Increased sebum production. And we were surprised to find how such a simple addition made a big difference in our ability to study acne."
Liu noted that in this work, genetically identical mice were used, illustrating that the differences in the severity of the acne were due to bacterial strain differences, not something in the mice.

The researchers want to make the mouse model better by applying bacteria topically rather than by injection near the skin. They also want to learn more about the genetics of P. acnes strains and how they interact with human sebum. These efforts may help create better therapies and identify individuals who are at risk of serious acne.

Get some tips on dealing with acne from the video above by Mayo Clinic.


Sources: AAAS/Eurekalert! via University of California San Diego, JCI Insight

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
JUL 11, 2020
Microbiology
A Good Germ Can Protect Us From a Nasty One
JUL 11, 2020
A Good Germ Can Protect Us From a Nasty One
E. coli is a microbe that is commonly found in the intestinal tract, where it can exist harmlessly. However, if it gets ...
JUL 20, 2020
Genetics & Genomics
A Tiny But Efficient Cas Protein is Discovered in a Bacteriophage
JUL 20, 2020
A Tiny But Efficient Cas Protein is Discovered in a Bacteriophage
The microbes of the world are locked in a struggle for survival and a battle for resources. They compete directly in dif ...
JUL 27, 2020
Space & Astronomy
Bacteria More Lethal and Antibiotic Resistant in Space
JUL 27, 2020
Bacteria More Lethal and Antibiotic Resistant in Space
Research has shown that bacteria are more lethal and resistant to antibiotics when exposed to microgravity (a lack of gr ...
JUL 27, 2020
Microbiology
Vikings Carried, and Helped Spread Smallpox
JUL 27, 2020
Vikings Carried, and Helped Spread Smallpox
A global vaccination effort led to the official eradication of smallpox, but not before it killed over 300 million peopl ...
SEP 10, 2020
Space & Astronomy
Could There Be Life on Venus?
SEP 10, 2020
Could There Be Life on Venus?
Venus is the hottest planet in our solar system, reaching 465 degrees Celcius- a temperature hot enough to melt lead. Wh ...
SEP 15, 2020
Microbiology
If They Must, Methane-Eating Microbes Will Consume Ammonia
SEP 15, 2020
If They Must, Methane-Eating Microbes Will Consume Ammonia
There are many different kinds of microbes, and some can use unusual substances to survive. Methanotrophs, for example, ...
Loading Comments...