Gut microbiota signature in a cohort of Chinese patients with rosacea.

BACKGROUNDRosacea is a chronic inflammatory skin disease characterized by diverse symptoms and variable clinical progression, which can significantly impair patients' quality of life and mental health. The exact etiology of rosacea remains elusive. It has been hypothesized that specific microorganisms may trigger symptom onset and play crucial roles in the pathogenesis of the disease.

OBJECTIVEWe performed a case-control study to investigate the gut microbiome of rosacea patients compared to controls matched by age, sex in China.

METHODSThe study cohort comprised eight patients diagnosed with rosacea and eight age- and sex-matched healthy controls residing in Beijing. Metagenomic sequencing was performed using on a llumina Novaseq 6000 platform. Hospital Anxiety and Depression Scale was used to evaluate the severity of anxiety and depression of rosacea patients. Skindex-16 score was used to assess dermatology-specific health-related quality of life (HrQoL) in patients with rosacea. The clinical evaluation of acne was done using the ECLA score.

RESULTSThe rosacea patients showed higher HADS and Skindex-16 score (15.375 ± 1.302 and 46 ± 9.75 respectively) vs healthy controls (3.425 ± 1.308 and 0 respectively). A clear distinction was observed between the rosacea group and the control group, characterized by a significant increase in the abundance of Turicibacter_sp._TJ11, Turicibacter_sp._H121,Turicibacter_sp._TA25,Turicibacter_sp._T129,Ruminococcus_sp._AF18-22,Ruminococcus_sp._CAG:379,Ruminococcus_sp._AM2829LB,Ruminococcus_callidus, Ruminococcus_sp._AM36-18,Ruminococcus_sp._AF43-11,Ruminococcus_sp._AM28-41,Streptococcus sp. 23.2,Streptococcus infantarius, Streptococcus vestibularis, Streptococcus salivarius, Streptococcus gordonii, Clostridium_sp._CAG:798, Clostridium_tertium, Alistipes_sp._Z76 and Lachnospiraceae_bacterium_XBB2008in the rosacea group. In contrast, reduced levels were detected in the rosacea group for Clostridium_sp._AF12-41, Clostridium_sp._CAG:299, Clostridium_sp._OM05-5BH,Clostridium_sp._AF24-2LB, Clostridium_sp._AM18-55, Clostridium_sp._CAG:43, Clostridium_sp._OM047,Clostridium_sp._TF1113AC,Clostridium_sp._OF134,Clostridium_disporicum, Butyrivibrio_sp._CB08,Butyrivibrio_sp._INlla14, Roseburia_sp._CAG:50 (p < 0.05). Pearson correlation analysis revealed that Gemmiger_sp._An120 was positively correlated with Skindex-16 and negatively correlated with ECLA score (P < 0.05). Clostridium_sp._CAG:299 was negatively correlated with HADS scores and positive correlation with ECLA score (P < 0.05). KEGG pathway analysis found KO05034, KO04024 and KO00920 pathways exhibited increased activity in the Rosacea group (P < 0.05).

CONCLUSIONSThe gut microbiota in individuals with rosacea displayed changed from that of healthy control. These microbial alterations may contribute to the pathogenesis of rosacea through multiple mechanisms, including impairment of the intestinal barrier function, induction of pro-inflammatory cytokine release, and modulation of neurotransmitter synthesis. By integrating taxonomic shifts with functional alterations, this study provides deeper insights into the gut ecosystem changes associated with systemic inflammation in rosacea.