Metagenomic dna profile of intestinal microbiome in psoriasis patients

Introduction and Aim: The gut microbiome is a large colonization of bacteria, viruses, fungi, and protozoa found in the gastrointestinal tract. Beneficial bacteria of this community function as natural digestive organs by digesting plant polysaccharides that cannot be digested by the host. They are responsible for vitamin B and K2 and amino acid production, development of the immune system, and keeping it active, additional energy formation by helping digestion and absorption of some foods. Dysbiosis is the disruption in balance in the intestinal microbiota. It is influenced by various factors such as age, genetics, nutritional habits, geographic location, and antibiotic use. Dysbiosis has been associated with autoimmune and inflammatory diseases such as diabetes mellitus, obesity, inflammatory bowel disease, spondyloarthritis, cardiovascular diseases, autism, anxiety, depression in various studies. Microbiome analysis has also been used to explain the pathogenesis of some common dermatological diseases such as acne vulgaris, atopic dermatitis. It has been demonstrated that the gut microbiome plays a role in the pathogenesis of dermatological diseases in addition to the skin microbiome. Psoriasis is an immune-mediated chronic inflammatory disease with clinical manifestations and phenotypes of different severity, often characterized by demarcated erythematous, scaled plaques. Although the etiopathogenesis of the disease could not be clarified, genetic, environmental, and immunological factors have been investigated to be involved. Psoriasis may be associated with comorbidities involving the gastrointestinal, cardiovascular, and musculoskeletal systems. There is no clear treatment yet. In this study, we aimed to determine the possible relationship between psoriasis disease and the gut microbiome comparing with healthy individuals to contribute to psoriasis pathogenesis which may help to introduce new diagnosis and treatment approaches. Material and Method: 24 psoriasis patients without any other systemic and/or dermatological diseases, medication, probiotic/prebiotic use, and history of recent gastrointestinal surgery, and 16 healthy individuals with the same conditions as the control group were included in this study. Following nucleic acid isolation from fecal samples, bacterial 16S ribosomal RNA (rRNA) gene target sequencing was performed with the Illumina MiSeq system using universal bacteria 16S primers. After bioinformatics procedures, statistical analyzes were done. Taxons that differ significantly between groups were determined with the default settings. Results: The ratio of Firmucites / Bacteroidetes was found to be higher in patients with psoriasis than in the healthy control group (in patients with psoriasis; 4.91, in healthy volunteers; 1.85). Lachnospiraceae, Peptostreptococcaceae, Bacteroidaceae, Prevotellaceae family, Prevotella, Megasphera, Blautia, Dorea, Lachnoclostridium, Fusicatenibacter, Terrisporobacter ve Bacteroides genus, Prevotella copri ve Faecalibacterium prausnitzii, Bacteroides plebeius species amounts were found to be higher and Christensenellaceae, Ruminococcaceae, Victivallaceae, Oxalobacteriaceae, Porphyromonadoceae family, Ruminococcus, Oxalobacter, Victivallis, Alistipes, and Odoribacter genus were found to be lower with a statistically significance for both, in psoriasis patients (p <0.05 and LDA score> 2). In alpha diversity analysis, decreased microbiome diversity was found in psoriasis patients compared to the control group (according to PD and Chao1 indexes). In Beta variety, it was determined that the content of the species determined in two groups differed from each other as a result of Bray-Curtis analyzes (PC1 15.82% according to the amplicon sequence variant. PC1 40.31% by genus level). Conclusion: According to the results of the sequence analysis; phylogenetic diversity was decreased in psoriasis patients. There is a relationship between psoriasis and intestinal dysbiosis, and dysbiosis can be considered as an important factor in the pathogenesis of psoriasis, and prebiotics or probiotics can be introduced or supplemented in treatment modalities. Since there exist limited number of studies examining this issue in the literature, more comprehensive studies are needed to achieve more data in order to make accurate statements. Keyword: microbiota, psoriasis, 16S rRNA, dysbiosis, microbiome