In a recently published study in the International Journal of Molecular Sciences, a team of Polish researchers conducted a review to understand the relationship between the gut microbiome and dermatological diseases, and investigated the use of probiotics to correct gut microbiome dysbiosis as a treatment for various skin diseases.
While dermatological diseases are mostly non-fatal, they significantly contribute to the global public health burden, regardless of the impact of skin diseases on mental health and the quality of work and daily life due to discomfort and social stigmatization. Genetic and environmental factors often cause skin diseases. However, increasing research findings suggest that the gut microbiome, which plays a significant role in the progression of various types of diseases, also contributes to the development and progression of dermatological diseases.
Nucleic acid sequencing is widely used to explore bacterial genes, understand the composition, frequency, and diversity of the microbiome, and understand the crucial role that the gut microbiome plays in human health and homeostasis. It has been found that dysbiosis of the gut microbiome significantly influences the development and progression of various chronic diseases. Determining the contribution of microbiome dysbiosis to the pathogenesis and progression of dermatological diseases could help find new therapeutic options for skin diseases.
Function of the Gut Microbiome
In the present review, the researchers discussed the structure and composition of the gut microbiome and its role in human health. The review revealed that the gut microbiome consists of over 1014 microorganisms, which collectively weigh as much as the human liver. Furthermore, over three million bacterial genes from the gut microbiome are responsible for the synthesis of numerous metabolites, some of which are essential for human health.
The studies examining the structure and composition of the gut microbiome mostly showed that the gut microbiota is acquired during prenatal developmental stages and the microbiome profile is established by the age of five or six, persisting into adulthood. Bacteroidetes and Firmicutes are the two most dominant bacterial groups in the healthy human gut microbiome, with individual differences in the proportions and composition of flora.
It is known that antibiotic use, genetics, diet, and lifestyle factors such as smoking, stress, poor sleep, exercise, and body mass index influence the profile of the gut microbiota. A diet mainly composed of fats, processed foods, and low in fiber has been known to drive the gut microbiome towards an inflammatory profile.
Dermatological Diseases and the Gut Microbiome
The review also included a detailed examination of the role of the gut microbiome in numerous dermatological diseases, including atopic dermatitis, psoriasis, acne, and alopecia areata. Studies have shown that the chronic nature of atopic dermatitis, particularly the persistence of itching despite taking medication, is known to significantly impact the quality of life and is associated with an increased risk of depression and anxiety. The review found that dysbiosis of the gut microbiome is strongly associated with atopic dermatitis.
Results from genome-wide association studies have shown that bacterial taxa such as z Bifidobacteriaceae, Bifidobacteria, Bifidobacterium, Christensenellaceae, Clostridia, Tenericutes show a negative correlation with the risk of atopic dermatitis, while Anaerotruncus, Bacteroides, and Bacteroidaceae show a positive correlation.
Furthermore, cases in which atopic dermatitis developed in adulthood had lower alpha diversity of the gut microbiome. Additionally, the richness and proportion of taxa differed between atopic dermatitis patients with and without gastrointestinal symptoms. Moreover, the reduction in alpha diversity was also associated with a higher risk for atopic dermatitis, severity, remission, and age of onset.
Genomic analyses of stool samples from psoriasis patients have found lower species diversity in their gut microbiome compared to healthy controls and significant dysbiosis. Additionally, the microbiomes of psoriasis patients and healthy controls both included Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes, with the abundance of Proteobacteria and Bacteroidetes being significantly lower, and that of Actinobacteria and Firmicutes being significantly higher in the gut microbiome of psoriasis patients.
The review also discussed the results of numerous studies on the association between the gut microbiome and the development, symptoms, severity, and progression of acne and alopecia areata.
In summary, the review examined numerous studies that investigated the relationship between the gut microbiome and dermatological diseases such as atopic dermatitis, psoriasis, acne, and alopecia areata. The findings suggest that dysbiosis of the gut microbiome at different stages of life is significantly associated with the development, severity, and progression of skin diseases.
Although there is limited research on the use of probiotics to alleviate the symptoms of various skin diseases, the review found that some studies have yielded positive results, highlighting the need to further explore the potential use of probiotics as a therapeutic option for skin diseases.
- Ryguła, I., Pikiewicz, W., Grabarek, BO, Wójcik, M. & Kaminiów, K. (2024). The Role of the Gut Microbiome and Microbial Dysbiosis in Common Skin Diseases. International Journal of Molecular Sciences, 25(4). DOI: 10.3390/ijms25041984, https://www.mdpi.com/1422-0067/25/4/1984