The Complicated Relationship of Short-Chain Fatty Acids and Oral Microbiome: A Narrative Review

Abstract

The human oral microbiome has emerged as a focal point of research due to its profound implications for human health. The involvement of short-chain fatty acids in oral microbiome composition, oral health, and chronic inflammation is gaining increasing attention. In this narrative review, the results of early in vitro, in vivo, and pilot clinical studies and research projects are presented in order to define the boundaries of this new complicated issue. According to the results, the current research data are disputable and ambiguous. When investigating the role of SCFAs in human health and disease, it is crucial to distinguish between their local GI effects and the systemic influences. Locally, SCFAs are a part of normal oral microbiota metabolism, but the increased formation of SCFAs usually attribute to dysbiosis; excess SCFAs participate in the development of local oral diseases and in oral biota gut colonization and dysbiosis. On the other hand, a number of studies have established the positive impact of SCFAs on human health as a whole, including the reduction of chronic systemic inflammation, improvement of metabolic processes, and decrease of some types of cancer incidence. Thus, a complex and sophisticated approach with consideration of origin and localization for SCFA function assessment is demanded. Therefore, more research, especially clinical research, is needed to investigate the complicated relationship of SCFAs with health and disease and their potential role in prevention and treatment.

Oral Microbiome Stamp in Alzheimer’s Disease

“…Despite numerous studies devoted to AD, a precise mechanism for the disease development still needs to be discovered. The scientific community currently targets the microbiome as a critical point in various diseases [ 34 ], including AD pathogenesis. This performed study provides the oral microbiome compartment peculiarities in Kazakhstanis in the interactions with clinical, demographic, and anamnestic data and laboratory parameters.…”

Mechanisms underlying the laxative effect of lactulose: A randomized placebo‐controlled trial showing increased small bowel water and motility unaltered by the 5‐HT3 receptor antagonist, ondansetron

“…46 Most are oral facultative anaerobic organisms which are capable of producing SCFAs though oral concentrations are much less than colonic. 42,47 Several studies have indicated that SCFAs stimulate propulsive motility in the terminal ileum 36 while in the colon they may both inhibit and stimulate propulsive motility depending on the type and concentration. 48 SCFAs act by activating the G protein coupled receptors (GPRs), GPR41 and GPR43 which are expressed on Peptide YY containing enteroendocrine cells in rats 49 and humans.…”

Salivary Metabolites Produced by Oral Microbes in Oral Diseases and Oral Squamous Cell Carcinoma: A Review

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