Effect of Enteromorpha polysaccharides on gut-lung axis in mice infected with H5N1 influenza virus
Yanyi Huang1, Peiyang Zhang2, Shuyi Han1
1National Research Center for Wildlife-Borne Diseases, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; College of Life Science, University of Chinese Academy of Sciences, Beijing, China.
Abstract:
Enteromorpha polysaccharides (EPPs) have been reported to have antiviral and anti-inflammatory properties. To explore the effect of EPPs on H5N1-infected mice, mice were pretreated with EPPs before being infected with the H5N1 influenza virus intranasally. H5N1 infection resulted in body-weight loss, pulmonary and intestinal damage, and an imbalance of gut microbiota in mice. As a result of the inclusion of EPPs, the body weight of mice recovered and pathological damage to the lung and intestine was reduced. EPPs also diminished inflammation by drastically lowering the expression of proinflammatory cytokines in lungs and intestines. H5N1 infection reduced bacterial diversity, and the abundance of pathogenic bacteria such as Desulfovibrio increased. However, the beneficial bacteria Alistipes rebounded in the groups which received EPPs before the infection. The modulation of the gut-lung axis may be related to the mechanism of EPPs in antiviral and anti-inflammatory responses. EPPs have shown potential in protecting the host from the influenza A virus infection.
Insights
Enteromorpha polysaccharides (EPPs) show promise in combating H5N1 influenza virus. Pretreatment with EPPs protected mice from H5N1 infection, reducing damage and restoring gut microbiota balance.
Area of Science:
- Marine Biology
- Immunology
- Microbiology
Background:
- Enteromorpha polysaccharides (EPPs) possess known antiviral and anti-inflammatory properties.
- Influenza A virus (H5N1) infection causes significant host damage, including pulmonary and intestinal pathology and gut dysbiosis.
- The gut-lung axis plays a crucial role in host defense and disease pathogenesis.
Purpose of the Study:
- To investigate the protective effects of EPPs against H5N1 influenza virus infection in a mouse model.
- To evaluate the impact of EPPs on H5N1-induced pathological changes, inflammation, and gut microbiota.
- To explore the potential mechanism of EPPs involving the gut-lung axis.
Main Methods:
- Mice were pretreated with EPPs prior to intranasal inoculation with the H5N1 influenza virus.
- Assessment of body weight changes, pulmonary and intestinal tissue damage, and inflammatory cytokine expression.
- Analysis of gut microbiota composition using 16S rRNA sequencing.
Main Results:
- EPP pretreatment significantly improved body weight recovery and reduced lung and intestinal pathological damage in H5N1-infected mice.
- EPPs markedly decreased the expression of pro-inflammatory cytokines in the lungs and intestines.
- H5N1 infection led to reduced bacterial diversity and increased pathogenic bacteria (e.g., Desulfovibrio), while EPPs promoted the recovery of beneficial bacteria (e.g., Alistipes).
Conclusions:
- EPPs demonstrate significant antiviral and anti-inflammatory potential against H5N1 influenza virus infection.
- EPPs modulate the gut microbiota, suggesting a role in regulating the gut-lung axis.
- EPPs offer a promising therapeutic strategy for protecting against influenza A virus infections.
