DYSBIOSIS ASSOCIATED TO AZITRHOMYCIN ADMINISTRATION

PIQUERAS VIRGINIA; JAIME CRISTIAN; GIAJ MERLERA GUILLERMO; VELEZ PABLO; BEAUZ ANDREA; CORREA SILVIA

Modalidad virtual

Congreso; Reunión anual de sociedades de biociencias 2021. SAIC. SAI. AAFE. NANOMED.AR; 2021

SAIC. SAI. AAFE. NANOMED.AR

The intestinal microbiota represents a complex community of microorganisms inhabiting the intestine. It plays an important role in development and maintenance of the immune system and gastrointestinal functionality. Alterations in the composition of the microbiota (dysbiosis) can initiate or enhance autoimmune or inflammatory diseases. Among the factors that cause dysbiosis, the administration of antibiotics is one of the most frequent, although not all have been characterized. In this work we evaluated the impact on the intestinal microbiota of the acute administration of azithromycin (AZM). Adult male C57BL/6 mice received (50 mg/kg/day) in drinking water for 5 days and stool samples were collected to evaluate composition and density of the microbiota by T-RFLP and flow cytometry (FC), material from the small and large intestine (SI and LI) to evaluate mucus by colorimetric methods, luminal content for measuring markers of metabolic profiles by GC-MS and proximal and distal mesenteric lymph nodes (MLN) to assess CD3, CD4, CD8 and CD19 lymphoid subsets by FC. In control samples from two different years the analysis of samples compared to databases suggests the same composition in terms of phyla evidencing the stability of the microbiota in our colony. Compared with control group, the results of the comparison with the database shows modifications in the abundance of the main phyla with an increase in Firmicutes and Actinobacteria and decrease of Bacteroidetes after AZM administration. The antibiotic produced a decrease in mucus levels (up to 50% in SI and up to 75% in LI); the analysis of colon content of mice treated with AZM and controls showed similar profiles. For lymphoid subsets, in proximal MLN percentage and absolute numbers of CD3+, CD4+, CD8+ subsets were similar with an increase in % of CD19+ cells (p=0,0723): in distal MLN instead, we found a trend in the frequency of CD8+ and CD19+ subsets.In our study we included microbiological, biochemical and molecular biology methods to evaluate the dysbiosis caused by AZM in the gut microbiota.