Search Results (28)

Background: Secretory immunoglobulin A (sIgA) plays a key role in oral and mucosal immunity, serving as a first-line defense against pathogens. Smoking is known to negatively affect immune function, but data on the impact of heated tobacco products such as IQOS^® on sIgA levels are limited. Objective: To assess and compare the effects of conventional cigarette smoking and IQOS^® use on the concentration of salivary sIgA in healthy individuals. Methods: A total of 200 participants were enrolled and divided into three groups: 60 non-smokers, 70 conventional cigarette smokers, and 70 IQOS^® users. Unstimulated whole saliva samples were collected and analyzed for sIgA concentration using ELISA method. Statistical analysis was performed using IBM SPSS Statistics 25. Results: Mean salivary sIgA levels were significantly lower in both cigarette smokers (246.03 μg/mL) and IQOS^® users (243.54 μg/mL) compared to non-smokers (380.74 μg/mL, p < 0.05). No significant difference was observed between cigarette smokers and IQOS^® users. A pronounced reduction in sIgA was seen in female users of both tobacco products, whereas male users did not show a statistically significant decline. Conclusions: Both cigarette smoking and IQOS^® use are associated with a significant decrease in salivary sIgA levels, particularly in females. The findings suggest that IQOS^® does not offer an immunological advantage over conventional smoking in terms of preserving mucosal immunity. Further studies are needed to confirm these findings and explore underlying mechanisms. Full article

Anxiety and depression are highly prevalent mental health disorders often associated with dysregulation of neuroendocrine and immune systems, particularly the hypothalamic–pituitary–adrenal (HPA) axis and the sympathetic–adrenal–medullary (SAM) system. Recent research highlights the potential of salivary biomarkers to serve as non-invasive indicators for psychological distress. This narrative review synthesizes current evidence on key salivary biomarkers, cortisol, alpha-amylase (sAA), secretory immunoglobulin A (sIgA), chromogranin A (CgA), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), brain-derived neurotrophic factor (BDNF), and salivary microRNAs (miRNAs), in relation to anxiety, depression, and stress. A comprehensive literature search (2010–2025) was conducted using multiple databases and relevant MeSH terms. The review reveals consistent associations between these salivary analytes and stress-related disorders, reflecting changes in neuroendocrine activity, immune response, and neuroplasticity. Cortisol and sAA mirror acute stress reactivity, while cytokines and CRP indicate chronic inflammation. BDNF and miRNAs provide insight into neuroplastic dysfunction and gene regulation. Despite promising results, limitations such as variability in sampling methods and biomarker specificity remain. In conclusion, salivary biomarkers offer a promising avenue for early detection, monitoring, and personalization of treatment in mood and anxiety disorders. Conclusions: Cortisol and alpha-amylase serve as the principal markers of acute stress response, whereas cytokines such as IL-6 and TNF-α, together with CRP, indicate chronic inflammation associated with extended emotional distress. Full article

Childhood obesity and overweight are linked to subclinical inflammatory conditions. The present manuscript aimed to undertake a scoping review exploring the relationship between childhood obesity and salivary biomarkers to answer the following question: “Are salivary biomarkers trustful factors/indicators for childhood obesity?” The main search terms used were: “obesity and salivary biomarkers and children” (Pubmed, Scielo, Scopus, Embase databases: 1999–2025). Assessed articles were carefully classified according to a predetermined criterion (Newcastle–Ottawa Scale), and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were considered. Papers involving children >13 years, duplicates/triplicates, literature reviews, and non-related to the question addressed were excluded. More than 30 salivary biomarkers were assessed in the thirteen studies appraised. Three studies were rated as having a high level of evidence, two as moderate, and eight as having a low level. Fourteen biomarkers were found to be significantly increased in childhood obesity/overweight (p < 0.05): leptin, insulin, α-amylase, tumor necrosis factor α, interleukin 6, vascular endothelial growth factor-A, C-reactive protein, monocyte chemotactic protein-1, resistin, phosphate, nitric oxide, interleukin 1β, uric acid and fetuin-A; and three were found to be significantly decreased (p < 0.05): adiponectin, secretory immunoglobulin A, and interleukin-12p70. In conclusion, the present review supported the idea that saliva might be a promising diagnostic tool in early life and that it is a significant source of obesity biomarkers in children. Full article

Dental fear and anxiety are frequently identified as major contributing factors to non-compliance, uncooperativeness, and difficulties during dental procedures in pediatric patients. These issues can lead to avoidance of dental treatment, resulting in long-term negative consequences for oral health and overall well-being. The assessment and quantification of psychological functioning (i.e., dental fear, anxiety, and self-perceived stress) has traditionally relied on self-reported questionnaires validated for the pediatric population. While this approach is cost-effective and non-invasive, it relies on subjective self-reported data, oftentimes influenced by parental or guardian interaction, especially in young children. Salivary diagnostics has recently emerged as an objective method for the procurement of biological molecules that serve as biomarkers for a variety of oral and systemic conditions. This literature review aims to comprehensively summarize the available literature on the correlation between psychological and salivary physiological measurements assessing dental fear, dental anxiety, and self-perceived stress in pediatric dental patients, highlighting the advantages and disadvantages of each method of assessment. Four databases (PubMed^®, PsycInfo, Dentistry & Oral Sciences Source, and Web of Science) were searched for published articles, in the English language, assessing the correlation between psychological and physiological distress in children undergoing dental procedures. Studies on pediatric patients reveal positive correlations between salivary cortisol and dental fear, stress, and anxiety, especially in returning patients. Conversely, findings on salivary alpha-amylase and secretory immunoglobulin A were inconsistent, with some studies suggesting correlations with dental fear and prior dental experiences. Full article

Background/Objectives: Volleyball training camps are known to reduce salivary secretory immunoglobulin A (s-SIgA); however, when it begins to decrease is unclear. The validity of a simple device for quantifying s-SIgA is lacking; hence, this study aimed to observe detailed s-SIgA changes during a volleyball training camp after moving to a high altitude and to investigate the difference in s-SIgA response between the two quantification methods, namely, the enzyme-linked immunosorbent assay (ELISA) and lateral flow device (LFD). Methods: Twenty-four male university volleyball players participated in the observational study. Measurements were collected at three points of the training camp (days 1, 4, and 7). The s-SIgA was quantified using conventional ELISA and the new LFD method. Results: The s-SIgA concentrations quantified using the two methods decreased significantly by day 4 (p < 0.05) and continued to decrease until day 7 (p < 0.05). A significant positive correlation was found between the s-SIgA concentrations quantified using the LFD and ELISA (p < 0.05, r_s = 0.319). Conclusions: These results indicate that a high-altitude volleyball training camp may suppress oral immune function by day 4 and that the evaluation of s-SIgA concentration using the LFD method is beneficial. A faster and easier method for assessing s-SIgA could contribute to athletes’ condition management strategies. Full article

Background/Objective: Conventional techniques for evaluating hydration status include the analysis of blood, urine, and body weight. Recently, advancements in dentistry have introduced capacitance sensor-based oral epithelial moisture meters as promising avenues for assessment. This study aimed to examine the correlation between oral mucosal moisture content, as determined using a capacitance sensor, and exercise-induced dehydration. Methods: A total of 21 participants engaged in a 120 min slow distance exercise session. A series of measurements were taken before and after the exercise session, including body weight, sweat rate, secretory immunoglobulin A (s-IgA) concentration in saliva samples, saliva flow rate, and oral mucosal moisture content, which were assessed using a capacitance sensor. The relationship between physical dehydration and oral mucosal moisture content was investigated using statistical analysis. Receiver operating characteristic curves were constructed to ascertain whether variations in oral mucosal moisture content could discern body mass losses (BMLs) of 1.5% and 2%. Results: A significant correlation was observed between the sweat rate during exercise and the change in oral mucosal moisture content before and after exercise (Spearman’s rank correlation coefficient: ρ = −0.58, p < 0.001). The salivary flow and s-IgA secretion rates were lower after the exercise period than before, whereas the s-IgA concentration was higher. Oral mucosal moisture decreased during the exercise period. Receiver operating characteristic curve analysis revealed that differences in oral mucosal moisture content exhibited discriminative capabilities, with area under the curve values of 0.79 at 1.5% BML and 0.72 at 2% BML. Conclusions: The measurement of oral mucosal moisture using capacitance sensors represents a promising noninvasive approach for the assessment of exercise-induced dehydration. Full article

Background: Respiratory tract infections remain among the leading causes of mortality worldwide. The COVID-19 pandemic has highlighted the importance of mucosal immunity in defending against infectious agents. Vitamin A is known to influence the production of secretory immunoglobulin A (SIgA) predominantly in the gut, where it is a critical component of the first line of defense on mucosal surfaces. Methods: This cross-sectional study, conducted 14 days post-positive COVID-19 diagnosis, aimed to determine the relationship between the nutritional status of vitamin A and SIgA levels in COVID-19 outpatients. Serum and saliva samples were collected. Vitamin A nutritional status was determined based on the assessment of dietary intake and the analysis of retinol-binding protein 4 (RBP4). SIgA levels were analyzed from salivary samples. In addition, serum antibodies were analyzed. Results: Dietary vitamin A intake and RBP4 levels positively correlated with SIgA. Patients with higher vitamin A intake showed higher SIgA/IgG1 and SIgA/IgG3 ratios, while those with higher RBP4 levels showed higher SIgA/IgM, SIgA/IgG1, and SIgA/IgG2 ratios. Conclusions: These findings underscore a significant correlation between vitamin A nutritional status and SIgA levels in COVID-19 outpatients, which may suggest the potential importance of maintaining optimal vitamin A levels for the prevention of viral infections. Full article

This study investigated whether Lactobacillus paragasseri SBT2055 (LG2055) activates plasmacytoid dendritic cells (pDCs) and suppresses common cold symptoms in healthy adults. Cell-based experiments showed that a LG2055 treatment upregulated CD86 and HLA-DR expression in pDCs, indicating that LG2055 activates pDCs in vitro. In a subsequent randomized, double-blind, placebo-controlled, parallel-group comparative trial, 200 participants were randomly divided into two groups and consumed three capsules with or without LG2055 once daily for 12 weeks. The primary outcome was the score on a daily physical health questionnaire survey of common cold symptoms. Three participants discontinued the trial and six participants were excluded from the analysis, thus 191 participants (95 in the LG2055 group and 96 in the placebo group) were analyzed. The LG2055 group showed a significantly higher ratio of “without symptoms” responses for runny nose, plugged nose, sneezing, sore throat, hoarseness, and chill than the placebo group. Furthermore, a stratified analysis revealed that LG2055 intake enhanced CD86 and HLA-DR expression in the pDCs of the participants with low secretion rates of salivary secretory immunoglobulin A. These data suggest that LG2055 suppresses the subjective symptoms of the common cold by activating pDCs and improving the host’s immune system in healthy adults, especially in immune-weakened individuals (UMIN000049183). Full article

Zoological institutions aim to continually improve the lives of the animals under their stewardship. To this end, bull elephants are now increasingly maintained in all-male groups to mimic social conditions observed in the wild. While cortisol is the most frequently used “stress” biomarker, secretory immunoglobulin A (sIgA) as a measure of health and positive affect, and the social hormone, oxytocin, are increasingly viewed as additional markers of welfare. The introduction of a pair of bull elephants to an existing group of three bull elephants at Denver Zoo presented an opportunity to assess sIgA, oxytocin and cortisol in response to the socialization process. In this study, sIgA varied greatly between individuals and did not correlate with cortisol but did correlate with salivary oxytocin. sIgA and oxytocin concentrations differed the most between social and solo situations during the introduction period compared to before bulls were introduced, and after a stable group had been formed. In contrast to findings in some species, sIgA and oxytocin were higher when housed alone than socially. Nonetheless, these results suggest that sIgA and oxytocin may be involved in social engagement and establishment of new social dynamics, and thus provide more insight into overall welfare states. Full article

Although nurses’ fatigue affects their well-being and patient safety, no effective objective measurements exist. We explored the profiles of salivary biomarkers associated with nurses’ chronic fatigue across several shifts. This longitudinal study involved 45 shiftwork nurses and collected their saliva samples before two night and two day shifts for a month. Chronic fatigue was measured using the Cumulative Fatigue Symptom Index before the first night shift. Biomarker profiles were analyzed using hierarchical cluster analysis, and chronic fatigue levels were compared between the profiles. Cortisol profiles were classified into high- and low-level groups across two day shifts; the low-level group presented significantly higher irritability and unwillingness to work. Secretory immunoglobulin A (s-IgA) profiles across the four shifts were classified into high- and low-level groups; the high-level group had significantly higher depressive feelings, decreased vitality, irritability, and unwillingness to work. Cortisol (two day shifts) and s-IgA (four shifts) profiles were combined, and (i) cortisol low-level and s-IgA high-level and (ii) cortisol high-level and s-IgA low-level groups were identified. The former group had significantly higher chronic fatigue sign and irritability than the latter group. The profiles of salivary cortisol and s-IgA across several shifts were associated with nurses’ chronic fatigue. Full article

Extremely Low-Frequency Electromagnetic Field (ELF MF) therapy is effective in the treatment of injury, inflammation and postoperative complications. Its clinical applications relate to bone unification, pain reduction, soft tissue oedema and the decrease of electric potentials in the oral cavity. It enhances regeneration of periapical bone lesions. It is obvious that cells (leukocytes, platelets, keratinocytes, osteoblasts) and proteins (fibrin, collagen, elastin and growth factors) exhibit alterations when exposed to an Extremely Low-Frequency Electromagnetic Field. The aim of the study was to evaluate the effect of an Extremely Low-Frequency Electromagnetic Field (ELF MF) on the parotid gland on the concentration of salivary immunoglobulin A. The study group consisted of 24 patients, aged 14–16, who underwent ELF MF on the parotid gland region. The control group comprised 25 matching persons. The IgA concentration in saliva samples was established using radial immunodiffusion. Following ELF MF, a statistically significant increase in the concentration of secretory immunoglobulin A was found in the study group, whereas in the control group, no statistically significant differences were noted. It can be concluded that an Extremely Low-Frequency Electromagnetic Field increases the activity of the immune system of the parotid gland. Full article

We aimed to assess the effect of oral probiotics containing the Streptococcus salivarius K12 strain on the salivary level of secretory immunoglobulin A, salivation rate, and oral biofilm. Thirty-one consenting patients meeting the inclusion criteria were recruited in this double-blind, placebo-controlled, two-arm, parallel-group study and randomly divided into probiotic (n = 15) and placebo (n = 16) groups. Unstimulated salivation rate, concentration of salivary secretory immunoglobulin A, Turesky index, and Papillary-Marginal-Attached index were assessed after 4 weeks of intervention and 2 weeks of washout. Thirty patients completed the entire study protocol. We found no increase in salivary secretory immunoglobulin A levels and salivary flow rates in the probiotic group compared with placebo. Baseline and outcome salivary secretory immunoglobulin A concentrations (mg/L) were 226 ± 130 and 200 ± 113 for the probiotic group and 205 ± 92 and 191 ± 97 for the placebo group, respectively. A significant decrease in plaque accumulation was observed in the probiotic group at 4 and 6 weeks. Within the limitations of the present study, it may be concluded that probiotic intake (Streptococcus salivarius K12) does not affect salivation rates and secretory immunoglobulin A salivary levels but exhibits a positive effect on plaque accumulation. Trial registration NCT05039320. Funding: none. Full article

Sjögren’s syndrome (SS) is a chronic autoimmune disease characterized by dry mouth and dry eyes, with lymphocytic infiltration of the exocrine glands. Saliva is becoming a useful tool to determine the clinical and pathological characteristics of SS because the collection method is easy and non-invasive. Since 1900, salivary proteomic analysis has been performed continuously using a variety of optimized analytical methods. Many studies have identified distinct characteristics of salivary proteins in patients with primary SS, and the changes were related to chronic inflammation and overproduction of immunoglobulins or downregulated secretory function. Several proteomic studies using whole or parotid saliva have evaluated whether several salivary proteins can be used to discriminate SS, including salivary β2-microglobulin, calprotectin, carbonic anhydrase VI, neutrophil gelatinase-associated lipocalin, sialic acid-binding immunoglobulin-like lectin-5, and tripartite motif-containing protein 29. In addition, salivary proinflammatory cytokine levels have been reported to be increased in patients with SS. Although these candidate salivary proteins have exhibited considerable differences in patients with SS, more data are needed to confirm their role as biomarkers. Moreover, the identification of salivary characteristics that can accurately reflect disease activity, predict treatment response and prognosis, and diagnose SS is anticipated. Full article

Athletes’ oral health appears to be poor in numerous sport activities and different diseases can limit athletic skills, both during training and during competitions. Sport activities can be considered a risk factor, among athletes from different sports, for the onset of oral diseases, such as caries with an incidence between 15% and 70%, dental trauma 14–70%, dental erosion 36%, pericoronitis 5–39% and periodontal disease up to 15%. The numerous diseases are related to the variations that involve the ecological factors of the oral cavity such as salivary pH, flow rate, buffering capability, total bacterial count, cariogenic bacterial load and values of secretory Immunoglobulin A. The decrease in the production of S-IgA and the association with an important intraoral growth of pathogenic bacteria leads us to consider the training an “open window” for exposure to oral cavity diseases. Sports dentistry focuses attention on the prevention and treatment of oral pathologies and injuries. Oral health promotion strategies are needed in the sports environment. To prevent the onset of oral diseases, the sports dentist can recommend the use of a custom-made mouthguard, an oral device with a triple function that improves the health and performance of athletes. During training, the sports dentist must monitor the athletes and the sports examination protocol must be implemented with the inclusion of the clinical examination, quantitative and qualitative analysis of saliva and instructions on the use, cleansing and storage of the mouthguard. Full article

Influenza virus and severe acute respiratory syndrome coronavirus (SARS-CoV-2) have caused respiratory diseases worldwide. Coronavirus disease 2019 (COVID-19) is now a global health concern requiring emergent measures. These viruses enter the human body through the oral cavity and infect respiratory cells. Since the oral cavity has a complex microbiota, influence of oral bacteria on respiratory virus infection is considered. Saliva has immune molecules which work as the front line in the biophylactic mechanism and has considerable influence on the incidence and progression of respiratory viral infection. Salivary scavenger molecules, such as gp340 and sialic acid, have been reported to exert anti-influenza virus activity. Salivary secretory immunoglobulin A (SIgA) has potential to acquire immunity against these viruses. Biological features of the oral cavity are thought to affect viral infection in respiratory organs in various ways. In this review, we reviewed the literature addressing the impact of oral conditions on respiratory infectious diseases caused by viruses. Full article