Nicotine pouch use induces alterations in salivary metabolites and metabolic pathways. Preliminary study based on NMR spectroscopy

Abstract Introduction Nicotine, a addictive substance in tobacco products, has profound negative impacts on oral and systemic health. This study aims to investigate salivary metabolites and metabolic pathways in nicotine pouch users. Methods This study included 28 participants. Of these, 13 individuals used nicotine pouches referred to as nicotine group (NG). Control group (HCs) contains 15 healthy subjects, who do not use any nicotine products. Whole mouth saliva samples were collected in three ways: unstimulated saliva (US-WMS); sub-pressure stimulated saliva (SPS-WMS), and stimulated saliva (S-WMS). Saliva samples were analysed using nuclear magnetic resonance (NMR) spectroscopy, and the metabolic pathway analysis was conducted using the MetaboAnalyst 6.0 platform. Results A total of 35 salivary metabolites were quantified. In NG, salivary choline both in US-WMS and S-WMS showed elevated levels when compared to HCs. The six metabolic pathways in NG were assessed: Phosphatidylethanolamine Biosynthesis (PB; highest Pathway Impact score), Glucose-Alanine Cycle, Phosphatidylcholine Biosynthesis, Phospholipid Biosynthesis, Lactose Degradation, and Trehalose Degradation. Discussion High level of choline have seen in NG affecting the cholinergic system due to deleterious properties of nicotine. In NG, disruption of PB metabolism can lead to salivary gland dysfunction, characterized by reduced saliva secretion and altered composition. Furthermore, dysregulation of PB metabolism has been linked to various systemic diseases. More studies are needed, a more detailed characterization of different product use could have improved the nicotine intake models, and the effects of smoking cessation on salivary metabolome could bring information about the health benefits of this process.