# Gut microbial communities in chronic rhinosinusitis patients in response to 1,8-Cineol treatment

## TL;DR

This study shows that 1,8-Cineol, a plant-based drug, treats chronic rhinosinusitis without harming the gut microbiome, unlike antibiotics.

## Contribution

Demonstrates that 1,8-Cineol preserves gut microbial diversity and promotes beneficial bacteria like Akkermansia muciniphila.

## Key findings

- 1,8-Cineol treatment does not disturb the gut microbiome and maintains bacterial diversity.
- Akkermansia muciniphila levels increase during 1,8-Cineol administration.
- 1,8-Cineol is a safer alternative to antibiotics for treating CRS.

## Abstract

•Chronic rhinosinusitis (CRS) patients reveal a dysbacteriosis of the nasal microbiota and increased levels of bacterial pathogens such as Staphylococcus aureus, which is suggested to trigger the development of nasal polyps.•Common treatment options for chronic rhinosinusitis patients include systemic antibiotics, which are well known to influence the microbial composition of the gut, including a decrease in bacterial diversity and an increase in antibiotic resistance.•Plant-based anti-inflammatory monoterpene 1,8-Cineol is commonly used as the clinically approved drug Soledum® for the treatment of inflammatory airway diseases including CRS replacing need for antibiotic therapy.•Anti-inflammatory 1,8-Cineol does not cause overall disturbances of the physiologic gut microbial community, but promotes increased abundances of intestinal Akkermansia muciniphila, which has gained increasing attention as a promising probiotic bacterial species.•Thus, 1,8-Cineol outcompetes antibiotic therapy by the means of lack of negative side effects on the gut microbiome, thereby promising increased patient´s wellbeing and reduced development of antimicrobial resistance following treatment.

Chronic rhinosinusitis (CRS) patients reveal a dysbacteriosis of the nasal microbiota and increased levels of bacterial pathogens such as Staphylococcus aureus, which is suggested to trigger the development of nasal polyps.

Common treatment options for chronic rhinosinusitis patients include systemic antibiotics, which are well known to influence the microbial composition of the gut, including a decrease in bacterial diversity and an increase in antibiotic resistance.

Plant-based anti-inflammatory monoterpene 1,8-Cineol is commonly used as the clinically approved drug Soledum® for the treatment of inflammatory airway diseases including CRS replacing need for antibiotic therapy.

Anti-inflammatory 1,8-Cineol does not cause overall disturbances of the physiologic gut microbial community, but promotes increased abundances of intestinal Akkermansia muciniphila, which has gained increasing attention as a promising probiotic bacterial species.

Thus, 1,8-Cineol outcompetes antibiotic therapy by the means of lack of negative side effects on the gut microbiome, thereby promising increased patient´s wellbeing and reduced development of antimicrobial resistance following treatment.

Chronic rhinosinusitis (CRS) is a widespread inflammatory disease of the paranasal sinuses and the standard treatment includes surgery and the administration of corticosteroids or antibiotics. Antibiotics are well known to influence the microbial composition of the gut, including a reduced bacterial diversity and an increased antibiotic resistance. This underlines the need for alternative treatment approaches, especially regarding vulnerable patients such as children. Therefore, we evaluated the intestinal microbiota of CRS patients regarding plant-based anti-inflammatory monoterpene 1,8-Cineol, which is administered as the clinically approved drug Soledum® for the therapy of different inflammatory airway diseases including CRS.

Microbiome analysis from stool samples was performed from 31 CRS patients before and after 1,8-Cineol administration using 16S rRNA gene next generation sequencing using dissimilarity-based and taxonomic approaches.

Data revealed elevated abundances of specific taxa including Bacteroides and Faecalibacterium as part of the physiologic gut microbial community and no overall disturbances in response to 1,8-Cineol treatment. Of note, abundances of intestinal Akkermansia muciniphila tend to increase during the course of 1,8-Cineol administration.

Our data recommend 1,8-Cineol as a valuable addition to the current standard treatment of inflammatory diseases, without running the risk of profound changes of the gut microbial community.

Image, graphical abstract