Search Results (160)

Precision nutrition is an emerging approach that tailors dietary recommendations based on an individual’s unique genetic, metabolic, microbiome, and lifestyle factors. β-hydroxybutyrate (β-HB) is a key ketone body produced during fat metabolism, especially in states of fasting, low-carbohydrate intake, or prolonged exercise. Therefore, monitoring β-HB levels provides valuable insights into an individual’s metabolic state, making it an essential biomarker for precision and personalized nutrition. A smartphone-connected electrochemical biosensor for single-use, rapid, low-cost, accurate, and selective detection of β-HB in whole blood and saliva at the Point-of-Care (POC) is reported. A graphite screen-printed carbon electrode modified with potassium ferricyanide (Fe(III)GSPE) was used as an electrode platform for the deposition of β-hydroxybutyrate dehydrogenase (HBDH), nicotinamide adenine dinucleotide oxidized form (NAD⁺), and chitosan nanoparticles (ChitNPs). An outer poly(vinyl) chloride (PVC) diffusion-limiting membrane was used to protect the modified electrode. The biosensor showed a linear range in the clinically relevant range, between 0.4 and 8 mM, with a detection limit (LOD) of 0.1 mM. The biosensor was tested on human blood and saliva samples, and the results were compared to those obtained with a commercial ketone meter, showing excellent agreement. Full article

Beta-thalassemia major is an inherited disorder that requires lifelong blood transfusions, with the risk of complications including poor oral health and dental caries. The objective of this study was to compare the oral microbiome diversity and composition in transfusion-dependent thalassemia patients and relate it to oral hygiene and dental caries. A cross-sectional analysis of 35 patients of beta-thalassemia major aged 6–18 years was performed. The status of oral hygiene was examined through the Oral Hygiene Index—Simplified (OHI-S) and Decayed, Missing, and Filled Teeth (DMFT) index. Saliva was taken for DNA extraction, followed by the 16S rRNA sequencing of V3-V4 hypervariable regions. The bioinformatics pipeline in QIIME2 was utilized for analyzing the comparison of microbial composition and diversity in groups of varying oral hygiene status and severity of caries. Metagenomic analysis revealed 3334 Amplicon Sequence Variants (ASVs), of which the most prevalent genera were Streptococcus, Haemophilus, Veillonella, Rothia, and Prevotella. High-oral-hygiene groups presented increased levels of cariogenic bacteria, while moderate-oral-hygiene groups presented an equilibrated microbiome. No statistically significant differences in microbial diversity were found between the study groups (p > 0.05). This study sheds light on the critical importance of oral hygiene in microbiome diversity in patients with beta-thalassemia major. Full article

The oral cavity harbors a highly intricate and dynamic microbial ecosystem of multiple microhabitats supporting diverse microbial populations. As the second most complex microbiome in the human body, surpassed only by the gut, the oral microbiome comprises over 1000 species. Disruptions in the microbial balance have been associated with an increased risk of both oral diseases (dental caries and periodontitis) and systemic conditions, including inflammatory diseases and certain types of cancers. In our pilot study, we purified bacterial DNA from pre-treated, saponin-based, host-depleted saliva samples and performed 16S amplicon sequencing, using Oxford Nanopore Technologies, to identify bacterial composition and investigate changes in the oral microbiota of patients with solid tumors in response to chemotherapy, either alone or in combination with immunotherapy. We found significant reductions in microbial diversity of the oral microbiota following cancer treatment, which may contribute to post-therapeutic complications such as oral mucositis. Moreover, our findings indicate that on the one hand, following chemotherapy treatment the microbial profile is characterized by an increased abundance of Streptococcus, Gemella, and Granulicatella and a decrease in the abundance of Neisseria and Veillonella. On the other hand, post combined treatment, only Streptococcus relative abundance increased, Veillonella exhibited a slight decline, and Haemophilus and Neisseria displayed a marked decrease, whilst Granulicatella and Gemella remained relatively stable. Our findings underline the impact of cancer therapy on the oral microbiome, highlighting the potential for precision-based strategies to restore microbial balance and minimize treatment-related complications. Full article

Background: This study explores the link between oral biofluids, microbial dysbiosis, and Alzheimer’s disease (AD), highlighting saliva and gingival crevicular fluid (GCF) as non-invasive diagnostic sources. AD onset and progression appear to be influenced not only by genetic and environmental factors but also by changes in the oral microbiome and related inflammatory and metabolic alterations. As global populations age, the incidence of AD is projected to rise significantly. Emerging evidence implicates the oral microbiome and salivary metabolites in neurodegenerative pathways, suggesting that oral health may mirror or influence brain pathology. Materials and Methods: A systematic review of recent multi-omics studies was performed, focusing on salivary and GCF analysis in patients with AD, those with mild cognitive impairment (MCI), and cognitively healthy individuals. Databases searched included PubMed, Web of Science, and Scopus, following PRISMA guidelines. Results: Across the 11 included studies, significant alterations were reported in both the salivary microbiome and metabolome in AD patients. Notable microbial shifts involved increased abundance of Veillonella parvula and Porphyromonas gingivalis, while key metabolites such as L-tyrosine, galactinol, and mannitol were consistently dysregulated. These biomarkers correlated with cognitive performance and systemic inflammation. Conclusions: Oral biofluids represent promising, accessible sources of biomarkers for early AD detection. Multi-omics integration reveals the oral–brain axis as a potential target for diagnosis, monitoring, and therapeutic strategies. Full article

Background/Purpose: Coronavirus disease 2019 (COVID-19) has become the cause of a global health crisis during the pandemic. This research aimed to study the impact of symptomatic COVID-19 on children’s oral health indices and salivary microbiome composition during the post-COVID-19 period. Methods: An observational, cross-sectional study was conducted in Tbilisi (Georgia) among children aged 7–12 years. A total of 421 children included in the study had a history of laboratory-confirmed COVID-19 within one year of exposure. No participants met the criteria for comorbid conditions or for PCC. A stratified simple random selection of schools and among selected clusters was used. The selected children were divided into two groups: the exposed group, who were patients with a history of symptomatic COVID-19, and the control group, who were patients with a history of asymptomatic COVID-19. The data were collected from August 2022 to December 2023. Oral screening, microbiological examination of saliva, and administration of questionnaires were also performed. Logistic regression was used to calculate ORs with 95% confidence intervals. The statistical processing of the data was performed with SPSS 23.0. This study was approved by the Biomedical Research Ethical Council of the University of Georgia (UGREC–04–22/9 March 2022). Results: Statistically significant differences in the means of the oral health indicators between the studied groups were detected (exposed: DMFT + deft = 5.9; MGI = 0.92; S-OHI = 1.9; control: DMFT + deft = 3.8; MGI = 0.56; S-OHI = 1.4). According to the logistic regression, symptomatic COVID-19 had a significant effect on the following oral health indicators: DMFT + deft (OR = 1.26; 95% CI = 1.14–1.39), MGI (OR = 2.31; 95% CI = 1.50–3.55), and S-OHI (OR = 3.43; 95% CI = 2.03–5.76). The effect of symptomatic COVID-19 on the frequency of eradication of the studied microbiome was also significant (OR = 2.12; 95% CI = 1.23–3.63). Conclusions: A close association was established between symptomatic COVID-19 and microbiome changes in the oral saliva of children, as well as between oral health indicators and symptomatic COVID-19. Considering the research results, it is assumed that a symptomatic course of COVID-19 may be an additional risk factor associated with poor oral health in the pediatric population in the post-COVID-19 period. Full article

Periodontal diseases are highly prevalent in dogs and intricately interconnected with the composition and functional attributes of the oral microbiota. The demand for non-invasive interventions to support oral health presents an opportunity for functional ingredients. The novel postbiotic heat-treated (HT) Lactiplantibacillus plantarum CECT 9161 inhibited growth and biofilm formation of oral microorganisms in vitro. The in vitro growth of saliva-derived biofilms was also inhibited and revealed microbiome modulation. Two doses of the postbiotic (LOW: 5 mg dog/day, HIGH: 25 mg/dog/day) were assessed in a placebo-controlled, double-blinded, 57-day clinical trial involving 60 dogs. Associations were found between the postbiotic, reduced plaque formation, and modulation of the oral microbiome, including increased abundance of genes involved in denitrification, heme and catechol biosynthesis, and oxidative stress reduction. The results suggest that HT Lactiplantibacillus plantarum CECT 9161 may support oral health in dogs by modifying the microbiome of supragingival plaque and reducing plaque formation. Full article

Background and Objectives: Menopause is a natural physiological process involving hormone production changes, affecting many functions and systems. This scoping review offers a contemporary outlook on oral issues related to menopause, such as saliva production, periodontal and alveolar bone issues, and changes in the microbiome, and it also investigates the effects of hormonal therapy. Materials and Methods: A literature search from 2019 to 2024 was conducted according to PRISMA-ScR guidelines. Articles investigating the oral effects of menopause were included. Results: A total of 30 studies were covered; 8 focused on salivary alterations, 5 on periodontal issues, 7 on bone, 3 on the microbiome, and 7 on multiple oral problems, showing that xerostomia and altered taste are the most common oral manifestations, followed by indirect causal effects on periodontitis. Many of these alterations can be contained through regular consultations and adequate hygiene. Some alveolar bone changes may occur after menopause and are associated with osteoporosis. Conclusions: Postmenopausal women experience notable reductions in salivary flow, pH levels, and taste sensitivity, which are associated with hormonal fluctuations as well as factors such as age, medication use, and treatments for climacteric symptoms. This population is at increased risk for periodontitis, tooth loss, altered taste, lichen planus, candidiasis, and decreased bone mineral density, which also affect the peri-implant area. Osteoporosis and hormonal changes can play a significant role in causing these increased risks. Maintaining proper oral hygiene and consistently monitoring bone health are essential. While changes in the oral microbiome are more heavily influenced by reductions in salivary flow than by menopause itself, hormone therapy may help improve periodontal health by reducing harmful bacteria and fostering a more balanced microbial environment. The intricate impact of hormones on oral health highlights the necessity for further research. Full article

Background: According to the One Health concept, the physical proximity between pets and their owners facilitates the interspecies spread of bacteria including those that may harbor numerous antimicrobial resistance genes (ARGs). Methods: A shotgun sequencing metagenomic data-based bacteriome and resistome study of 1830 canine saliva samples was conducted considering the subsets of ARGs with higher public health risk, ESKAPE pathogen relatedness (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species), and survey results on the physical and behavioral characteristics of the participating dogs. Results: A total of 318 ARG types achieved sufficiently high detection rates. These ARGs can affect 31 antibiotic drug classes through various resistance mechanisms. ARGs against tetracyclines, cephalosporins, and, interestingly, peptides appeared in the highest number of samples. Other Critically Important Antimicrobials (CIAs, WHO), such as aminoglycosides, fluoroquinolones, or macrolides, were among the drug classes most frequently affected by ARGs of higher public health risk and ESKAPE pathogen-related ARGs of higher public health risk. Several characteristics, including coat color, sterilization status, size, activity, or aggressiveness, were associated with statistically significant differences in ARG occurrence rates (p < 0.0500). Conclusions: Although the oral microbiome of pet owners is unknown, the One Health and public health implications of the close human–pet bonds and the factors potentially underlying the increase in salivary ARG numbers should be considered, particularly in light of the presence of ARGs affecting critically important drugs for human medicine. Full article

Background and Objectives: Preterm birth (PTB), defined as delivery before 37 weeks of gestation, remains a significant public health concern due to its association with neonatal morbidity and mortality. Although studies have suggested that microbial factors in vaginal microbiota (VMB) influence PTB, longitudinal research on Korean women is limited. This study aimed to analyze VMB differences between term and preterm pregnancies in Korean women and their correlation with the cervical length (CL). Materials and Methods: A cohort of 60 pregnant Korean women (40 who had a term birth (TB) and 20 who had a PTB) was recruited. Vaginal samples were collected at five time points (first, second, and third trimester; 1–2 weeks postpartum; 1–2 months postpartum). Microbial DNA was extracted and analyzed using quantitative PCR targeting 12 bacterial species. The CL was measured in the second and third trimesters. Results: Lactobacillus crispatus was consistently dominant in the TB group, whereas PTB cases exhibited greater microbial diversity with elevated levels of Prevotella salivae and Ureaplasma species. The CL was significantly shorter in PTB cases, correlating with shifts in the VMB composition. Conclusions: A stable, Lactobacillus-dominant microbiome is protective in pregnancy, while increased diversity in PTB cases suggests microbial biomarkers for early risk prediction. Combining VMB profiling with CL measurement may enhance early, non-invasive PTB risk assessments. Full article

Background/Objectives: Microbial biofilms on denture surfaces pose significant oral and systemic health risks. Although chemical denture cleansers are widely used, they can cause mucosal irritation and disrupt the oral microbiome. The aim of this study was to evaluate the antimicrobial efficacy and biocompatibility of a denture cleanser containing Paeonia lactiflora extract (DC-PL) as a potential natural alternative. Methods: Oral microcosm biofilms were formed using human saliva and matured over 6 days. Then, the biofilms were treated for 1 min daily over 6 days with DC-PL, distilled water (DW; negative control), or Polident^® (PD; positive control). Antimicrobial effects were assessed by measuring the red fluorescence intensity (ratio of red to green fluorescence intensity [Ratio_R/G]) and aciduric bacterial counts. Biocompatibility was evaluated through an oral mucosal irritation test. A one-way analysis of variance followed by Tukey’s post hoc test was used for between-group comparisons. Results: Ratio_R/G in the DC-PL group was significantly lower than that in the DW group (0.94-fold, p = 0.021) and comparable with that in the PD group (p = 0.502). Aciduric bacterial counts in the DC-PL group were 0.92-fold lower than those in the DW group (p = 0.037) and comparable with those in the PD group (p = 0.460). The oral mucosal irritation index was 0, indicating no irritation. Conclusions: DC-PL demonstrated antimicrobial efficacy similar to that of PD while maintaining excellent biocompatibility. These findings underscore its potential as a safe and effective alternative to conventional chemical cleansers, offering a clinically viable solution for improving oral health management. Full article

This study investigated changes in physiological processes and rumen microbial communities in does from mid-gestation to lactation and identified potential associations between these physiological changes and the rumen microbiome. Additionally, we studied the transmission mechanisms of microorganisms between the dam and offspring. Our study demonstrates significant changes in maternal physiological metabolism, immune status, and rumen microbiota from mid-pregnancy through lactation. We identified potential associations between these physiological changes and the rumen microbiome. Moreover, the findings highlight that alterations in maternal physiological metabolism and immune status significantly influence the growth and immune development of offspring kids. Additionally, we observed that the maternal microbiota serves as a key source of gastrointestinal microbial communities in young animals, with early colonization of maternally derived microbes in the offspring’s gastrointestinal tract playing a role in shaping their immune system development. The results for primary outcomes are as follows: The serum levels of estrogen and progesterone in pregnant does were greater than those observed during lactation, while the concentration of growth hormone, triiodothyronine, and glucose exhibited an upward trend during lactation. During late gestation, the serum IL-10 concentration in does decreased, while the TNF-α concentration increased. Additionally, on day 140 of gestation, does showed a significant decrease in IgG, total protein, and globulin levels. From mid-gestation to lactation, the abundance of dominant phyla and genera, including Firmicutes, Bacteroidetes, Patescibacteria, Bacteroidales_RF16_group, Clostridia_UCG-014, RF39, and Eubacterium_ventriosum_group, in the rumen of does underwent significant changes. LEfSe analysis identified a series of marker microorganisms in the rumen of does at different physiological stages. A correlation was observed between these dominant bacteria and the serum physiological indicators of the does. Notably, rumen volatile fatty acids also exhibited a correlation with serum physiological indicators. In addition, serum physiological indicators of does were significantly correlated with the growth and immune indicators of their kids. Microbiological origin analysis revealed that the gastrointestinal microbiome of kids primarily originated from the rumen, birth canal, and milk of does. Further analysis identified a correlation between the kids’ serum immunometric indicators and certain gastrointestinal microorganisms. In particular, the jejunum microbiota of 28-day-old lactating kids, including Alysiella, Neisseria, and Muribaculaceae, showed a significant positive correlation with serum IL-6 and IL-10 levels. Meanwhile, these genera were dominant in the saliva and milk of does, suggesting a direct microbial transfer from dam to offspring. These microbial communities may play a significant role in modulating the metabolism and immune responses of the offspring, thereby influencing their immune system development. Full article

The microbiome plays a crucial role in cancer development, influencing fundamental processes such as cell proliferation, apoptosis, immune system regulation, and host metabolism. Recent studies have highlighted a possible relationship between esophageal cancer and the oral microbiota, making oral microflora a possible risk factor. The bacteria Prevotella intermedia, Tannerella forsythia, Streptococcus sanguinis, and Streptococcus mutans, implicated in various oral pathologies, were of interest in this study, which was initiated to examine their potential role in the etiology of esophageal squamous cell carcinoma (ESCC). To achieve this, a case-control design was used, with whole saliva samples collected from 24 healthy controls and 24 patients with esophageal squamous cell carcinoma. DNA was then extracted, and real-time PCR was performed to quantify the presence of the targeted bacteria in both groups. The results showed that all the bacteria studied were present in the saliva of both patients with ESCC and healthy controls. However, expression levels were significantly higher in patients with ESCC. Specifically, a marked increase in the presence of P. intermedia, T. forsythia, S. sanguinis, and S. mutans was observed in the patients with cancer compared to the healthy controls. In short, this study highlights a significant imbalance in the microbial flora, with an increased abundance of selected bacteria in patients with ESCC. The monitoring of these bacteria could thus be exploited to track patients who are at risk. Their integration into diagnostic and therapeutic strategies would offer new prospects for the early diagnosis and improved prognosis of patients at risk of ESCC. Full article

The composition of the human microbiome is a critical health indicator, and culture-independent methodologies have substantially advanced our understanding of human-associated microorganisms. However, precise identification and characterization of microbial strains require culture-based techniques. Recently, the resurgence of culturomics, combined with high-throughput sequencing technology, has reduced the high labor demand of pure culture methods, facilitating a more efficient and comprehensive acquisition of culturable microbial strains. This study employed an integrated approach combining culturomic and high-throughput sequencing to identify culturable microorganisms on the human scalp and in human saliva and feces. Several Staphylococcus strains were identified from the scalp, whereas anaerobic microorganisms were dominant in the saliva and fecal samples. Additionally, the study highlighted the beneficial effects of transportation conditions (liquid nitrogen treatment, dry ice transport, and dimethyl sulfoxide [DMSO] buffer) in preserving culturable microorganisms. A robust methodology was developed for the large-scale acquisition of culturable microorganisms with optimized transport conditions that enhance the potential for isolating a greater diversity of culturable strains. Full article

The Canary Islands, a region with high asthma prevalence, are frequently exposed to Saharan Dust Intrusions (SDIs), as are a wide range of countries in Europe. Alpha-1 antitrypsin (SERPINA1 gene) regulates the airway’s inflammatory response. This study analyzed the combined effect of SDI exposure and SERPINA1 variants on bacterial/fungal DNA concentrations in saliva and pharyngeal samples from asthmatic patients. Bacterial and fungal DNAs were quantified by qPCR in 211 asthmatic patients (GEMAS study), grouped based on their exposure to daily PM₁₀ concentrations. Associations between SDI exposure, microbial DNA concentrations, and nine variants in SERPINA1 were tested using linear regression models adjusted for confounders. The ratio between bacterial and fungal DNA was similar in saliva and pharyngeal samples. SDI exposure for 1–3 days was enough to observe significant microbial DNA change. Increased bacterial DNA concentration was detected when SDI exposure occurred 4–10 days prior to sampling, while exposure between days 1 and 3 led to a reduction in the fungal DNA concentration. The T-allele of SERPINA1 SNV rs2854254 prevented the increase in the bacterial/fungal DNA ratio in pharyngeal samples after SDI exposure. The bacterial/fungal DNA ratio represents a potential tool to monitor changes in the microbiome of asthmatic patients. Full article

Alzheimer’s disease (AD) is characterized by progressive cognition and behavior impairments. Diagnosing AD early is important for clinicians to slow down AD progression and preserve brain function. Biomarkers such as tau protein and amyloid-β peptide (Aβ) are used to aid diagnosis as clinical diagnosis often lags. Additionally, biomarkers can be used to monitor AD status and evaluate AD treatment. Clinicians detect these AD biomarkers in the brain using positron emission tomography/computed tomography or in the cerebrospinal fluid using a lumbar puncture. However, these methods are expensive and invasive. In contrast, saliva collection is simple, inexpensive, non-invasive, stress-free, and repeatable. Moreover, damage to the brain parenchyma can impact the oral cavity and some pathogenic molecules could travel back and forth from the brain to the mouth. This has prompted researchers to explore biomarkers in the saliva. Therefore, this study provides an overview of the main finding of salivary biomarkers for AD diagnosis. Based on these available studies, Aβ, tau, cholinesterase enzyme activity, lactoferrin, melatonin, cortisol, proteomics, metabolomics, exosomes, and the microbiome were changed in AD patients’ saliva when compared to controls. However, well-designed studies are essential to confirm the reliability and validity of these biomarkers in diagnosing and monitoring AD. Full article