The impact of liposomal linolenic acid on gastrointestinal microbiota in mice

BACKGROUND: The prevalence of Helicobacter pylori has long been a global health issue. Triple therapy, being the first-line treatment, has caused dysbiosis of the gastrointestinal tract that led to various complications. A novel nanomedicine – liposomal linolenic acid (LipoLLA) – has been proven to have great potential in eradicating H. pylori. However, the possible side effects of LipoLLA due to alteration of the gastrointestinal microbiota remain unknown. AIM: This study focused on the impact of LipoLLA on gastrointestinal microbiota in mice in comparison with triple therapy in order to assess the safety profile. METHODS: Mice were divided into five groups: blank control group; H. pylori control group; triple therapy group; low-dose LipoLLA group (25 mg/kg); and high-dose LipoLLA group (50 mg/kg). Fecal samples were collected before and after the intake of corresponding formulas. Gastric tissues were obtained after mice dissection. These samples were analyzed with high-throughput sequencing. RESULTS: The analysis revealed that LipoLLA resulted in minor gut microbiota alteration at different levels. The altered proportions in the high-dose group were higher than that of the low-dose group. On the other hand, the triple therapy group showed dramatic shifts in the major community composition. It displayed a notable boost in the relative abundance of Proteobacteria and Firmicutes along with a decrease in that of Verrucomicrobia and Bacteroidetes. All of them belonged to the major phyla in the microbiome. Triple therapy also led to the growth of the family Enterobacteriaceae, Enterococcaceae, and Clostridiaceae_1 that may be associated with clinical illnesses. Gastric microbiota analysis reached similar conclusions. CONCLUSION: Our findings indicated that LipoLLA causes minor gastrointestinal microbiota alterations while the triple therapy triggered dramatic changes. Thus, LipoLLA is not only promising but also a safe therapeutic medication to eradicate H. pylori infection.