Tongue microbiome of smokeless tobacco users

Abstract

Background: The possibility that smokeless tobacco may contribute to oral carcinogenesis by influencing the oral microbiome has not been explored. This preliminary cross-sectional study sought to assess the effect of using shammah, a form of smokeless tobacco prevalent in Arabia, on the tongue microbiome. Tongue scarping samples were obtained from 29 shammah users (SU; 27.34 ± 6.9 years) and 23 shammah non-users (SNU; 27.7 ± 7.19 years) and analyzed with 16S rRNA gene sequencing (V1-V3). Species-level taxonomy assignment of the high-quality, merged reads was obtained using a previously described BLASTn-based algorithm. Downstream analyses were performed with QIIME, LEfSe, and R. Results: A total of 178 species, belonging to 62 genera and 8 phyla were identified. Genera Streptococcus, Leptotrichia, Actinomyces, Veillonella, Haemophilus, Prevotella and Neisseria accounted for more than 60% of the average microbiome. There were no differences between the two groups in species richness and alpha-diversity, but PCoA showed significant separation (P = 0.015, ANOSIM). LEfSe analysis identified 22 species to be differentially abundant between the SU and SNU. However, only 7 species maintained a false discovery rate of ≤0.2 and could cluster the two groups separately: Rothia mucilaginosa, Streptococcus sp. oral taxon 66, Actinomyces meyeri, Streptococcus vestibularis Streptococcus sanguinis and a potentially novel Veillonella species in association with SU, and Oribacterium asaccharolyticum with SNU. Conclusion: These preliminary results indicate that shammah use induces tongue microbiome changes including enrichment of several species with high acetaldehyde production potential, which warrants further investigation.

Tongue microbiome in children with autism spectrum disorder

“…Hence, comparing our results against others will be limited to healthy adult samples. At the phylum level, our results are identical to what we revealed previously among healthy adults [ 44 ], and almost similar to what was revealed by Seerangaiyan et al except for tiny proportions of Saccharobacteria, Spirochetes and SR1 in our sample but not theirs, and somewhat high proportion of TM7 in theirs, but not in ours [ 25 ]. At the genus level, the similarity with the above two studies is almost perfect, although with noticeable differences in the relative abundance, in addition to absence of Capnocytophaga and Atopopium in our study.…”

“…The tongue microbiome has been scarcely assessed and in contexts other than autism and not involving children [ 25 , 27 , 43 , 44 ]. Hence, comparing our results against others will be limited to healthy adult samples.…”

The Role of the Microbiome in Oral Squamous Cell Carcinoma with Insight into the Microbiome–Treatment Axis

“…Lee et al, 2017, noted significant variations in the salivary microbiome of those with OSCC and oral premalignant lesions in the genera Bacillus, Enterococcus, Parvimonas, Peptostreptococcus, and Slackia [61]. Indeed, an interesting species is Rothia mucaliginosa, which was found to be abundant in leukoplakic lesions, but less so within OSCC lesions, indicating a possible role in early OSCC establishment [62]. An excellent producer but poor detoxifier of acetaldehyde, this species imparts significant oxidative stress in oral keratinocytes [63].…”

Oral Microbiota Composition and Function Changes During Chronic Erythematous Candidiasis

“…Both bacteria are normal inhabitant of the human oral cavity and their abundance changed a lot in some abnormal status of oral cavity. It has been reported that the abundance of Rothia mucilaginosa was significantly increased in tongue leukoplakia lesions ( Amer et al., 2017 ) and smokeless tobacco users ( Halboub et al., 2020 ). And the abundance of oral Streptococcus mitis was reported to have changed a lot in periodontitis patients ( Lundmark et al., 2019 ).…”