Exploring the Gut Microbiome's Association in Psoriasis and Psoriatic Arthritis: A Scoping Review

Area of Science:

• Microbiology
• Immunology
• Dermatology

Background:

• Psoriasis (PsO) and psoriatic arthritis (PsA) are chronic inflammatory diseases.
• Current treatments primarily involve immune-modulating medications.
• There is growing interest in gut microbiome-based therapies for PsO/PsA.

Purpose of the Study:

• To review global studies on the association between gut microbiota and PsO/PsA.
• To understand the role of the gut microbiome in the pathogenesis of PsO/PsA.
• To explore the efficacy of gut microbiome-targeted therapies.

Main Methods:

• A scoping literature review was conducted.
• PubMed was searched for studies published between 2015-2025.
• Thirty studies involving 749,275 participants were included.

Main Results:

• Eighteen studies found significant gut microbiome differences in PsO/PsA patients compared to controls.
• Variations in the Firmicutes/Bacteroides ratio were observed, linked to short-chain fatty acid (SCFA) production.
• SCFAs, acetate and propionate, were associated with the IL-23/Th17 axis and keratinocyte activation.
• Therapies like ustekinumab and tofacitinib altered gut microbiota.
• Probiotic interventions showed mixed outcomes, with some improving SCFA producers or reducing inflammation.
• Fecal microbiota transplantation (FMT) showed benefits in mice but not in human trials.

Conclusions:

• Gut microbiome alterations are associated with inflammation and immune responses in PsO/PsA.
• The gut microbiome represents a potential therapeutic target for PsO/PsA.
• Further research is needed to optimize microbiome-based interventions.