The main purpose of this article is to develop a new and reliable saliva-based clinical diagnostic method for the early detection of oral squamous cell carcinoma (OSCC). This study used an immunoproteomic approach which allowed the detection of immunogenic host proteins in patients' samples using pooled human antibodies. In an attempt to investigate potential biomarkers of OSCC, two-dimensional electrophoresis (2-DE) followed by immunoblotting of saliva from patients and controls were compared. The protein spots of interest were analyzed using 2-DE image analyzer and subsequently subjected to MALDI-TOF/TOF and then matched against NCBI database. The result showed that four protein clusters, namely Human Pancreatic Alpha-amylase (HPA), Human Salivary Amylase (sAA), keratin-10 (K-10), and Ga Module Complexed with Human Serum Albumin (GA-HSA), had exhibited immunoreactivity in western blot. The results are suggestive of the potential use of the differentially expressed saliva protein as tumor biomarkers for the detection of OSCC. However, further studies are recommended to validate this finding.
Previous works on the effects of salivary alpha amylase in respond to various stressors report encouraging findings on it being a good indicator of stress. Ellestad protocol is a clinical procedure to screen for coronary artery disease by introducing exercise induced physical stress. If a salivary based biomarker profile in accordance to a stress test protocol could be established, the critical stress state which disable rational decision making could be ascertained in a standardized procedure. This technique would serve to aid human resource management in times of critical events such as rescue, firefighting or even military, that would potentially prevent unnecessary sacrifice of human lives. In this pilot study with five healthy volunteers performing the Ellestad protocol treadmill, a measurement profile with physiologic and salivary based biomarker is obtained. It is found that the alpha amylase levels or the changes in it as workload changes from resting-walking-running at ease-exhaustive running, is relatively more significant in reflecting the stress state than heart rate and blood pressure. Moreover, it is strongly associated with mood state with correlation coefficient of 0.8 and significance of 0.01.
Fresh samples of human whole saliva containing approximately 20-40 micrograms protein were analyzed using SDS-polyacrylamide slab gel electrophoresis systems. More than 20 protein bands were revealed by Coomassie Brilliant Blue R 250 staining. Some of the protein bands were shown to be glycoprotein-positive with PAS (periodic acid-Schiff) reagent. The protein bands with alpha-Amylase activity appeared within a molecular weight range of 120,000-180,000, which is 2 to 2.8 times higher than the normal molecular weight reported for alpha-Amylase from parotid saliva, and showed positive staining with PAS reagent. These results show that the alpha-Amylase in whole saliva appears to exist in a macromolecular form which is not dissociated in the presence of sodium dodecyl sulfate (SDS).
Milk-derived peptides have emerged as a popular mean to manage various lifestyle disorders such as diabetes. Fermentation is being explored as one of the faster and efficient way of producing peptides with antidiabetic potential. Therefore, in this study, an attempt was made to comparatively investigate the pancreatic α-amylase (PAA) inhibitory properties of peptides derived from milk of different farm animals through probiotic fermentation. Peptide's identification was carried out using liquid chromatography-quadrupole time-of-flight mass spectrometry and inhibition mechanisms were characterized by molecular docking. Results obtained showed a PAA-IC50 value (the amount of protein equivalent needed to inhibit 50% of enzymes) between 2.39 and 36.1 µg protein equivalent for different fermented samples. Overall, Pediococcus pentosaceus MF000957-derived fermented milk from all animals indicated higher PAA inhibition than other probiotic derived fermented milk (PAA-IC50 values of 6.01, 3.53, 15.6, and 10.8 µg protein equivalent for bovine, camel, goat, and sheep fermented milk). Further, molecular docking analysis indicated that camel milk-derived peptide IMEQQQTEDEQQDK and goat milk-derived peptide DQHQKAMKPWTQPK were the most potent PAA inhibitory peptides. Overall, the study concluded that fermentation derived peptides may prove useful in for managing diabetes via inhibition of carbohydrate digesting enzyme PAA.