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 over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
AUG 16, 2020
Microbiology
Newly Discovered Gut Enzyme Could Function as Disease Biomarker
AUG 16, 2020
Newly Discovered Gut Enzyme Could Function as Disease Biomarker
Bacteria in the gut have a powerful influence on our health, in part because all of those microbes have genes of their o ...
AUG 24, 2020
Immunology
Injectable Drug Stops HIV From Entering Cells
AUG 24, 2020
Injectable Drug Stops HIV From Entering Cells
Once in the body, HIV tracks down T cells that bear the CD4 receptor. It attaches to these immune cells, fusing itself w ...
OCT 05, 2020
Plants & Animals
Bacteria Caused the Deaths of Hundreds of Elephants
OCT 05, 2020
Bacteria Caused the Deaths of Hundreds of Elephants
African elephants are a threatened species that are increasing in some areas but at risk in many others. There are proba ...
OCT 11, 2020
Microbiology
Getting Closer to a Vaccine for Flaviviruses
OCT 11, 2020
Getting Closer to a Vaccine for Flaviviruses
Flaviviruses like dengue, West Nile, Zika, Japanese Encephalitis, and yellow fever infect over 400 million people a year ...
OCT 13, 2020
Microbiology
Bacterial Biofilms Can Take on Some Animal-Like Characteristics
OCT 13, 2020
Bacterial Biofilms Can Take on Some Animal-Like Characteristics
Bacteria are everywhere, even inside of our bodies, and they are thought to date back to the early days of life on Earth ...
NOV 05, 2020
Clinical & Molecular DX
Painless Microneedle Patch Diagnoses Malaria in Minutes
NOV 05, 2020
Painless Microneedle Patch Diagnoses Malaria in Minutes
It looks like a Band-Aid — a small, adhesive patch that is applied directly to the skin. This simple, low-cost dia ...
Loading Comments...