Intestinal Microbes Influence The Survival, Reproduction And Proteinprofile Of Trichinella Spiralis

Humans have intimately co-existed with diverse and complex microbiota for millions of years. Approximately 100 trillion microorganisms inhabit the gastrointestinal tract, the majority of which are bacteria. Playing a predominant role in health and disease, gut bacteria are linked with the host in a wide variety of relationships. Some parasitic worms also occupy a gastrointestinal niche for all or part of their lifecycle. Thus, gut bacteria live in close contact with gastrointestinaldwelling helminths. The interactions between intestinal microbes and parasitic worms play an essential role in the development of the host immune system. Trichinella spiralis(T. spiralis) was the most abundant of nine species of Trichinella, can infect humans and many other mammalian species. Undercooked meat contaminated with larva are swallowed, larvae would be released and migrate to the intestine, where they mature into adults and reproduce, sharing the same niche with gut bacteria. However, the effects of gut microbes on T. spiralis are unknown. The aim of this work was to explore microbe-induced alterations in the survival and reproduction of T. spiralis in vitro.The results showed Lactobacillus acidophilus and especially Lactobacillus bulgaricus significantly enhanced the survival and reproductive rates of nematodes. Salmonella enterica and especially E. coli O157: H(EHEC) had opposite effects. Nitric oxide(NO) production of the culture supernatant was detected by Griess reaction. In experiment we found that T. spiralis resisted EHEC by NO. To further identify the proteins and genes involved in the response of nematodes to microbes, quantitative proteomic analysis of T. spiralis was conducted by i TRAQ-coupled LCMS/MS technology and q RT-PCR was used to measure changes in m RNA expression. Genetic responses were activated mainly by EHEC. A total of 514 proteins were identified and quantified, and carbohydrate metabolism-related proteins existed in a higher proportion. These findings indicated that some gut bacteria are friendly or harmful for humans, and they may have similar beneficial or detrimental effects on parasites as well. This may be due to the regulation of the expression of specific genes and proteins. Our studies provide a basis for developing therapies against parasitic infections from knowledge generated by studying the gut microbes of mammals.