Salivary metabolomic profile associated with cariogenic risk in children

Saliva metabolomics: a non-invasive frontier for diagnosing and managing oral diseases

Salivary metabolomics represents a powerful noninvasive approach for diagnosing, monitoring, and managing oral diseases, providing valuable insights into the metabolic alterations associated with conditions such as oral cancer, oral precancerous lesions, periodontal diseases, and dental caries. Through the comprehensive analysis of salivary metabolites, this methodology facilitates the identification of disease-specific biomarkers reflective of underlying pathophysiological processes, including inflammation, microbial dysbiosis, and metabolic reprogramming. Despite its promising clinical potential, several significant challenges remain, notably the difficulty in establishing direct associations between specific salivary metabolites and distinct disease mechanisms, considerable inter-individual variability, and the inherent complexity of the oral microenvironment. Furthermore, issues related to data interpretation complexity, technological constraints, and the necessity for rigorous clinical validation continue to impede its broader clinical adoption. Nevertheless, ongoing advancements in analytical technologies and bioinformatics approaches hold considerable promise for addressing these limitations, positioning salivary metabolomics as a transformative tool for precision diagnosis and personalized treatment in oral health care.

Metabolomics for dental caries diagnosis: Past, present, and future

Dental caries, a prevalent global infectious condition affecting over 95% of adults, remains elusive in its precise etiology. Addressing the complex dynamics of caries demands a thorough exploration of taxonomic, potential, active, and encoded functions within the oral ecosystem. Metabolomic profiling emerges as a crucial tool, offering immediate insights into microecosystem physiology and linking directly to the phenotype. Identified metabolites, indicative of caries status, play a pivotal role in unraveling the metabolic processes underlying the disease. Despite challenges in metabolite variability, the use of metabolomics, particularly via mass spectrometry and nuclear magnetic resonance spectroscopy, holds promise in caries research. This review comprehensively examines metabolomics in caries prevention, diagnosis, and treatment, highlighting distinct metabolite expression patterns and their associations with disease-related bacterial communities. Pioneering in approach, it integrates singular and combinatory metabolomics methodologies, diverse biofluids, and study designs, critically evaluating prior limitations while offering expert insights for future investigations. By synthesizing existing knowledge, this review significantly advances our comprehension of caries, providing a foundation for improved prevention and treatment strategies.

Dimethyl Citraconate Alleviates Periodontitis via Activating the NRF2 Cascade

Nuclear factor erythroid 2-related factor 2 (NRF2) is a pivotal transcription factor that regulates redox signaling, playing a protective role in inflammation. Citraconate is verified as the strongest NRF2 agonist among its isomers. Dimethyl citraconate (DMC), an esterified derivative of citraconate, holds the potential for activating NRF2 and relieving inflammation. Here, we show that DMC is a strong NRF2-activating compound, stabilizing the intracellular NRF2 level and its nuclear translocation. DMC increases the expression levels of NRF2 downstream genes, thereby restricting the accumulation of reactive oxygen species and performing anti-inflammatory functions. The local administration of DMC effectively alleviates periodontal destruction in a ligation-induced periodontitis mouse model, elevating the NRF2 levels and downstream antioxidant enzymes. Moreover, the protective effect of DMC against periodontitis is absent in Nfe2l2-/- mice. Mechanically, DMC prolongs the half-life of NRF2 and facilitates its dissociation from KEAP1 (Kelch-like ECH-associated protein 1), which suggests that DMC interrupts the crosstalk between KEAP1 and NRF2. Collectively, our findings illustrate the role of DMC in activating NRF2 and ameliorating periodontal inflammation, suggesting its therapeutic potential for inflammation-related diseases.

Salivary metabolites profiling for diagnosis of COPD: an exploratory study

Pulmonary function tests (PFTs) are the gold standard for diagnosing of Chronic obstructive pulmonary disease (COPD). Given its limitation in some scenarios, it is imperative to develop new high-throughput screening methods for biomarkers in diagnosing COPD. This study aims to explore the feasibility of screening novel diagnostic biomarkers based on salivary metabolomics for the limited availability of PFTs and difficulties in implementation at primary care facilities. Participants were recruited from the outpatient department of West China Hospital. Saliva samples were collected to analyze the metabolites through the UPLC-Q-Exactive Orbitrap-MS platform. The raw data from the mass spectrometer was preprocessed with R software after peak extraction. The Wilcoxon rank sum test, Fold change analysis, PCA and orthogonal partial least squares - discriminant analysis were used to identify potential biomarkers. The receiver operating characteristic curve was used to assess the diagnostic efficacy of the predictive model generated by potential biomarkers. Saliva samples were collected from 66 patients with COPD and 55 healthy volunteers. Significant differences in the salivary metabolome between COPD patients and healthy controls were identified, with 261 differential metabolites recognized, 16 of which were considered as potential biomarker. The diagnostic model generated by these 16 biomarkers can successfully distinguish COPD patients from healthy people. Salivary metabolomic profiling is likely to emerge as a promising method for screening potential diagnostic biomarkers of COPD. Further prospective studies with large sample size are needed to verify the predictive value of these biomarkers in COPD diagnosis.Trial registrationThe study is registered with the China Clinical Trial Registry (www.chictr.org.cn/searchprojEN.html) on 26 September 2022, registration number: ChiCTR2200064091.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of select 2023 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertize in their subject areas that include (in order of appearance here): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine, oral and maxillofacial surgery, and oral radiology; and dental caries and cariology. The authors have focused their efforts on presenting information likely to influence the daily dental treatment decisions of the reader with an emphasis on current innovations, new materials and processes, emerging technology, and future trends in dentistry. With the overwhelming volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to inform and update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope readers find this work helpful in providing evidence-based care to patients seeking healthier and happier lives.

Manipulating the diseased oral microbiome: the power of probiotics and prebiotics

Dental caries and periodontal disease are amongst the most prevalent global disorders. Their aetiology is rooted in microbial activity within the oral cavity, through the generation of detrimental metabolites and the instigation of potentially adverse host immune responses. Due to the increasing threat of antimicrobial resistance, alternative approaches to readdress the balance are necessary. Advances in sequencing technologies have established relationships between disease and oral dysbiosis, and commercial enterprises seek to identify probiotic and prebiotic formulations to tackle preventable oral disorders through colonisation with, or promotion of, beneficial microbes. It is the metabolic characteristics and immunomodulatory capabilities of resident species which underlie health status. Research emphasis on the metabolic environment of the oral cavity has elucidated relationships between commensal and pathogenic organisms, for example, the sequential metabolism of fermentable carbohydrates deemed central to acid production in cariogenicity. Therefore, a focus on the preservation of an ecological homeostasis in the oral environment may be the most appropriate approach to health conservation. In this review we discuss an ecological approach to the maintenance of a healthy oral environment and debate the potential use of probiotic and prebiotic supplementation, specifically targeted at sustaining oral niches to preserve the delicately balanced microbiome.