The link connecting gut bacteria and psoriasis is inflammation, the authors said.
Citing numerous supporting studies, authors discuss how promising therapeutic probiotics may be able to prevent and treat the condition.
The link connecting gut bacteria and psoriasis is inflammation. Dysbiosis, or an imbalance of effector T cells and regulatory T cells in gut bacteria, can lead to chronic inflammatory disorders of the skin like psoriasis. Psoriasis is also often associated with intestinal inflammation conditions like inflammatory bowel disease.
“Through complex immune mechanisms, the gut microbiome has the ability to affect distant organ systems, including the skin,” the authors said.
Studies indicate a strong bidirectional correlation exists between gastrointestinal (GI) health and skin homeostasis, as many GI conditions are accompanied by skin manifestations. In several studies conducted on animals and humans, the administration of intestinal bacteria prompted benefits like increased blood flow and corneal hydration of the skin, along with a decrease in transepidermal water loss.
The intestinal microbiome also assisted in restoring the skin to homeostasis after a disturbance or stressor and enhanced the response to a disruption of skin barrier function. Notably, this occurred after ultraviolet radiation exposure.
Findings suggest “the intestinal microbiome produces metabolites that have immune-modifying potential and alter the balance between immune tolerance and inflammation.”
One study described how administrating Lactobacillus pentosus GMNL-77 as a probiotic to psoriatic mice significantly reduced erythema, scaling, and epidermal thickening compared with mice in the control group. Another group of mice which received Lactobacillus reuteri exhibited an accelerated wound healing time.
A study conducted with humans diagnosed with severe pustular psoriasis emphasized the effectiveness of probiotic treatments in patients. Previously these patients were unresponsive to several treatments including steroids, dapsone, and methotrexate. However, “after initiating Lactobacillus sporogenes supplementation 3 times per day, the patients showed significant clinical improvement within 2 weeks, with almost complete remission after 4 weeks,” the authors said.
Low-risk adverse effects and encouraging supporting studies lead authors to postulate that oral administration of beneficial gut bacteria can positively impact the management and prevention of various skin conditions, not just psoriasis.
This is significant, as skin conditions accounted for over 44 million physician office visits in the United States in 2015 and were among the top 20 main reasons for visits to family physicians, according to the CDC.
Alesa DI, Alshamrani HM, Alzahrani YA, Alamssi DN, Alzahrani NS, Almohammadi ME. The role of gut microbiome in the pathogenesis of psoriasis and the therapeutic effects of probiotics. J Family Med Prim Care. 2019;8(11):3496-3503. doi: 10.4103/jfmpc.jfmpc_709_19.