Saliva testing is a vital method for clinical applications, for its noninvasive features, richness in substances, and the huge amount. Due to its direct anatomical connection with oral, digestive, and endocrine systems, clinical usage of saliva testing for these diseases is promising. Furthermore, for other diseases that seeming to have no correlations with saliva, such as neurodegenerative diseases and psychological diseases, researchers also reckon saliva informative. Tremendous papers are being produced in this field. Updated summaries of recent literature give newcomers a shortcut to have a grasp of this topic. Here, we focused on recent research about saliva biomarkers that are derived from humans, not from other organisms. The review mostly addresses the proceedings from 2016 to 2022, to shed light on the promising usage of saliva testing in clinical diagnostics. We recap the recent advances following the category of different types of biomarkers, such as intracellular DNA, RNA, proteins and intercellular exosomes, cell-free DNA, to give a comprehensive impression of saliva biomarker testing.
Humans ; Saliva/metabolism* ; Biomarkers/metabolism* ; RNA ; Exosomes/metabolism*

Humans ; Occupational Diseases ; diagnosis ; Saliva ; chemistry ; metabolism ; Stress, Psychological ; diagnosis

The purpose of this study was to determine if salivary chromogranin a secretion in dogs exhibits a circadian rhythm. Saliva sampling was performed during three different sessions occurring in three nonconsecutive 24-h periods. Sixteen healthy adult beagle dogs (8 males and 8 females) were moved to a sampling room and housed individually in cages. Saliva samples were obtained every 4 h from 12:00 p.m. to 12:00 p.m. the following day. In the interest of habituation, saliva was obtained hourly from each dog 3 h before the experiment was started. Salivary chromogranin A concentrations were measured using an enzyme-linked immunosorbent assay. No circadian rhythm was detected for salivary chromogranin A secretion, and no differences in salivary chromogranin A concentrations measured every 4 h were demonstrated during the 24-h cycle in dogs.
Animals ; Chromogranin A/*analysis/*metabolism ; *Circadian Rhythm ; Dogs/*physiology ; Saliva/*chemistry

To study the salivary cortisol level, and to analyze the correlation between salivary cortisol and peri-abortion depression in the women suffering termination of pregnancy for fetal anomaly.
 Methods: Comparing the difference in salivary cortisol level between the women with and without depression when they underwent termination of pregnancy for fetal anomaly in a prospective cohort study. Analyzing the correlation between salivary cortisol and peri-abortion depression through logistics regression analysis.
 Results: The salivary cortisol awakening response was lower in women with depression than women without depression. Based on the logistics regression analysis, the salivary cortisol awakening response showed a negative correlation with pre-abortion (OR=0.063, 95% CI 0.005 to 0.754) and post-abortion (OR=0.002, 95% CI 0.000 to 0.061) depression.
 Conclusion: Cortisol awakening response possesses a negative correlation with peri-abortion depression, and it is a predictive factor for post-abortion depression.
Depression ; Depressive Disorder ; metabolism ; Female ; Humans ; Hydrocortisone ; metabolism ; Pregnancy ; Prospective Studies ; Saliva ; metabolism

OBJECTIVETo explore the endocrinal factors which influence the aggressive behavior of adolescents.

METHODSThe levels of cortisol (CORT), testosterone (T), prolactin (PRL), and growth hormone (GH) in saliva from 20 aggressive students and 20 non-aggressive control students were measured by radioimmunoassay (RIA). The students were matched for their gender, age, grade, stage of pubertal development, and economic status of their families.

RESULTSThe salivary T levels were 22.20 +/- 14.50 pg/mL and 19.54 +/- 12.52 pg/mL in aggressive male and female students, 13.20 +/- 6.85 pg/mL and 5.24 +/- 3.03 pg/mL in non-aggressive male and female students (P < 0.05). The male aggressive students had a lower level of CORT in saliva than non-aggressive male students (P < 0.05). There were no significant differences in the salivary levels of PRL or GH between the aggressive and non-aggressive groups. Correlation analysis revealed a negative relationship in male students between the salivary CORT levels and the aggression factor scores of the child behavior checklist (CBCL). In addition, the data also showed a positive relationship between the salivary T levels and the aggression factor scores of CBCL in female students. Multiple linear regression analysis showed that the salivary CORT level was an independent predictive factor for aggressive behaviors in adolescent boys. The higher the CORT level, the less aggressive the boys were.

CONCLUSIONCORT and T levels may play a certain role in adolescent aggressive behaviors.

Adolescent ; Aggression ; Child ; Female ; Growth Hormone ; metabolism ; Humans ; Hydrocortisone ; metabolism ; Male ; Prolactin ; metabolism ; Saliva ; metabolism ; Testosterone ; metabolism

PURPOSE: The present study was carried out to determine day-to-day differences in cortisol levels and the molar cortisol-to-dehydroepiandrosterone (DHEA) ratio (molar C/D ratio) in working subjects. MATERIALS AND METHODS: The cortisol and DHEA levels were measured from saliva samples collected 30 minutes after awakening for 7 consecutive days in full-time working subjects that worked Monday through Saturday. To determine the day-to-day differences within subjects, the collected data was analyzed using variance (ANOVA) for a randomized complete block design (RCBD). RESULTS: The cortisol levels from samples collected 30 minutes after awakening on workdays were similar to each other, but were significantly different from the cortisol levels on Sunday. The DHEA levels were not significantly different between the days of week. The DHEA levels on Monday and Tuesday were relatively lower than the levels on the other weekdays. The DHEA levels on Thursday and Friday were relatively higher than the other days. The molar C/D ratios on Sunday were significantly lower than those on workdays. The molar C/D ratios on Monday and Tuesday were significantly higher than those on Wednesday or other workdays. CONCLUSION: The cortisol levels and the molar C/D ratios demonstrate differences in adrenocortical activities between workdays and non-workdays, but the molar C/D ratio additionally represents differences in adrenocortical status between the first two workdays and other workdays. Thus, it is possible that the day-to-day differences in the cortisol levels and the molar C/D ratio represent the adrenal response to upcoming work-related stress.
Adult ; Analysis of Variance ; Dehydroepiandrosterone/*metabolism ; Female ; Humans ; Hydrocortisone/*metabolism ; Male ; Middle Aged ; Saliva/chemistry ; Work/*physiology

OBJECTIVETo compare the effect of citric acid stimulation on salivary alpha-amylase (sAA), total protein (TP), salivary flow rate, and pH value between Pi deficiency (PD) children and healthy children, thereby providing evidence for Pi controlling saliva theory.

METHODSTwenty PD children were recruited, and 29 healthy children were also recruited at the same time. Saliva samples from all subjects were collected before and after citric acid stimulation. The sAA activity and amount, TP contents, salivary flow rate, and pH value were determined and compared.

RESULTS(1) Citric acid stimulation was able to significantly increase salivary flow rate, pH value, sAA activities, sAA specific activity and sAA amount (including glycosylated and non-glycosylated sAA amount) in healthy children (P<0.05), while it could markedly increase salivary flow rate, pH value, and glycosylated sAA levels in PD children (P<0.05); (2) Although there was no statistical difference in determined salivary indices between the two groups (P>0.05), salivary indices except salivary flow rate and glycosylated sAA levels decreased more in PD children. There was statistical difference in sAA activity ratio, sAA specific activity ratio, and the ratio of glycosylated sAA levels between PD children and healthy children (P<0.05).

CONCLUSIONPD children had decreased response to citric acid stimulation.

Child ; Citric Acid ; therapeutic use ; Humans ; Medicine, Chinese Traditional ; Saliva ; Salivary alpha-Amylases ; metabolism ; alpha-Amylases

Salivary analysis can be used to assess the severity of caries. Of the known salivary proteins, a paucity of information exists concerning the role of proteinase 3 (PR3), a serine protease of the chymotrypsin family, in dental caries. Whole, unstimulated saliva was collected from children with varying degrees of active caries and tested using a Human Protease Array Kit and an enzyme-linked immunosorbent assay. A significantly decreased concentration of salivary PR3 was noted with increasing severity of dental caries (P<0.01); a positive correlation (r=0.87; P<0.01; Pearson's correlation analysis) was also observed between salivary pH and PR3 concentration. In an antibacterial test, a PR3 concentration of 250 ng·mL⁻¹ or higher significantly inhibited Streptococcus mutans UA159 growth after 12 h of incubation (P<0.05). These studies indicate that PR3 is a salivary factor associated with the severity of dental caries, as suggested by the negative relationship between salivary PR3 concentration and the severity of caries as well as the susceptibility of S. mutans to PR3.
Child ; Dental Caries ; enzymology ; Female ; Humans ; Male ; Myeloblastin ; metabolism ; Saliva ; enzymology

OBJECTIVE: To investigate distribution specificity of human fucosyltransferase 5 (FUT5) as well as its expression and localization in spermatids. METHODS: Human semen, vaginal swab, saliva and venous blood from healthy individuals were collected. The spermatids were isolated and the spermatid membrane protein was then extracted. Expression levels of FUT5 from human spermatid membrane, seminal plasma, vaginal fluid, saliva and serum were detected by immunoblotting technique. The expression and localization of FUT5 in spermatids were analyzed by immunofluorescent method. RESULTS: Immunoblotting technique showed that FUT5 was expressed on spermatid membranes and in serum, but not in seminal plasma, vaginal fluid and saliva. The expressed FUT5 on spermatids was mostly localized on head of spermatids by fluorescent microscopy, suggesting that there was certain amount of FUT5 on human spermatid membrane, and the spermatids might be isolated from mixed stains with vaginal fluid by antigen-antibody reaction. CONCLUSION Human FUT5 shows a characteristic distribution specificity, and this feature may be used for identification of mixed stain involved in criminal sexual offence in future forensic practice.
Cell Membrane/metabolism* ; Female ; Fluorescent Antibody Technique/methods* ; Forensic Genetics/methods* ; Fucosyltransferases/metabolism* ; Humans ; Immunoblotting ; Male ; Saliva/metabolism* ; Semen/metabolism* ; Spermatids/metabolism* ; Vagina/metabolism*

OBJECTIVETo study the variations of protein concentration in saliva stimulated and its effect on clinical diagnosis.

METHODSThe saliva from 33 normal controls and 73 patients with Sjögren syndrome (SS) who were stimulated with acid and not were collected. The concentration of beta 2 microglobulin (beta 2-mG), secretory immunoglobulin A (SIgA), and pH were measured by Radioimmunoassay, Rate Nephelometry and pH Detection Paper, respectively. SPSS 10.0 was used to determine the mean statistical differences among these groups.

RESULTSIn patients with SS, the concentration of beta 2-mG in saliva stimulated with Vc was significantly lower compared with that in saliva not stimulated (P < 0.01); In saliva stimulated with Vc, the concentration of beta 2-mG in patients with SS was higher than that in normal controls (P < 0.05). In normal controls, compared with that in saliva not stimulated, flow rate in saliva stimulated with 3% acetic acid and Vc was significantly higher (P < 0.01) and pH, concentration of beta 2-mG and SIgA were significantly lower (P < 0.01 and P < 0.05 respectively); there was a significant difference of flow rate, beta 2-mG, SIgA and pH in saliva between the subjects stimulated with 3% acetic acid and with Vc (P < 0.01).

CONCLUSIONSThe reason for the decrease of protein concentration in saliva stimulated may be the increase of flow rate caused by the decrease of pH or the decrease of pH itself. Protein detection of saliva stimulated in patients with SS is helpful in diagnosis, but the criterion is different between the saliva stimulated and not stimulated.

Adult ; Female ; Humans ; Hydrogen-Ion Concentration ; Immunoglobulin A, Secretory ; metabolism ; Male ; Saliva ; metabolism ; secretion ; Salivary Proteins and Peptides ; metabolism ; Sjogren's Syndrome ; diagnosis ; metabolism ; beta 2-Microglobulin ; metabolism