Saliva detection----the way of diagnosis in the future

Saliva detection----the way of diagnosis in the future

Saliva can be used for early diagnosis and treatment of oral and dental diseases, a concept that is not difficult to understand. However, if there are biomarkers in the saliva that reflect the general health status, some people will inevitably have to ask a question mark. In fact, saliva detection is not a newly proposed concept. As early as a few years ago, there was a news report on “Saliva diagnosis of AIDS”.

In 2008, Denny of the University of Southern California published an article in the Journal of Proteomics Research [J Proteome Res 2008, 7 (5): 1994] that there are 1,166 proteins in human saliva. Most of these proteins can be found in both plasma and tears. At the time, researchers suggested that biomarkers associated with disease could be found in these proteins, suggesting a new way for future clinical diagnosis.

Subsequent studies have found that levels of C-reactive protein, α-1B glycoprotein, and creatinine in human saliva are associated with cardiovascular disease, cancer, and kidney disease.

Saliva and diabetes

A study published recently in the Journal of Proteomics Research [J Proteome Res 2009, 8(1): 239] confirmed that salivary proteins are associated with type 2 diabetes.

By analyzing the salivary proteomics of type 2 diabetic patients and controls, Indian scholars discovered 487 proteins associated with type 2 diabetes in saliva. Of these, 33% of the protein has never been reported in human saliva. Among these proteins, the levels of 65 proteins differed by a factor of two in the saliva of patients and controls. Further analysis showed that some protein levels were significantly elevated in the saliva of patients with type 2 diabetes, and there was a corresponding increase in pre-diabetic patients. Therefore, it may be used as a biomarker for the future non-invasive diagnosis of type 2 diabetes and the discovery of pre-diabetes patients.

Saliva and cancer

As early as 2007, researchers at the MD Anderson Cancer Center in the United States reported in the Journal of International Oncology [Int J Oncol 2007, 30(3): 743], in patients with squamous cell carcinoma of the head and neck. In saliva, levels of α-1B glycoprotein and complement factor B protein were significantly elevated, whereas the two proteins were barely detectable in the saliva of the control. Correspondingly, levels of proteins such as cystine S and parotid secretory factors are present in the saliva of controls, but not in saliva of patients with head and neck squamous cell carcinoma.

At the time, the researchers wrote in the report that these proteins may be used as markers for clinical diagnosis of such cancers in the future.

Through an animal study, scientists have tried to exploit the mechanisms by which proteins in saliva change with tumors. Wong, of the University of California, Los Angeles, reported that tumors are associated with altered levels of protein in saliva in cancer model mice. It is speculated that tumors, like endocrine organs, secrete hormones, lymphokines, and cytokines, which are transported by blood. The distal organ has an effect on it. Once these factors reach the salivary glands, the transcriptional profile of the gene in the saliva changes, causing changes in the levels of certain proteins. These altered levels of protein will likely be an alternative biomarker for the detection of systemic tumors in saliva.

The researchers compared differences in levels of transcription factors in saliva between model mice of melanoma and non-small cell lung cancer as well as control mice. It was found that tumor mice had significant changes in transcriptomics in saliva compared to normal mice. Further analysis revealed that certain changes in transcriptomics are present in tumor tissues, blood, salivary glands, and saliva. Significant changes have been made in both types of gene transcription factors. In melanoma model mice, Runx1, Mlxipl, Trim30, and Egr1, Tbx1, and Nr1d1 were associated with 80.9% up-regulation of gene expression and 62.7% down-regulation of gene expression, respectively. Further analysis revealed that the abnormal product nerve growth factor (NGF) in melanoma tissue in mice can be used as an intermediary to induce the expression of the transcription factor Egr1 in the salivary gland (as shown).

The researchers believe that the results support that in the pathogenesis of systemic diseases, tumor tissue will cause disease-specific changes in certain proteins in saliva through certain intervening factors, and the proteins in these saliva become disease-specific biomarkers. potential.

Saliva and acute coronary syndrome

Recently, at the 87th session of the International Association of Dental Research, Miller of the University of Texas reported that changes in the levels of some proteins in saliva samples may be related to acute coronary syndrome (ACS), and people may pass the test in the future. The saliva component can diagnose ACS. It is not purely hypothetical to reaffirm the reference to "saliva biomarkers".

The study included non-stimulated saliva and saliva stimulation in 25 patients with ST-segment elevation myocardial infarction, 23 patients with non-ST-segment elevation myocardial infarction, and 43 controls. Saliva and blood samples were collected from patients 8 to 48 hours after diagnosis of myocardial infarction (MI).

The results indicate that the presence of ACS biomarkers in the blood can be detected in the saliva of MI patients, either in non-stimulated saliva or in saliva. The level of myosin in saliva of patients with MI was significantly higher than that of controls. Further analysis showed that stimulation of soluble intercellular adhesion molecule-1 (sICAM-1) in saliva was significantly associated with female MI, and C-reactive protein (CRP) in non-stimulated saliva was significantly associated with male MI. However, there was no significant difference in the composition of the above proteins in the saliva of ST-segment elevation and non-ST-segment elevation patients.

Researchers believe that some markers in saliva can effectively distinguish between MI and non-MI patients, and may provide new methods for rapid diagnosis. Further research needs to consider why saliva types (stimulation and non-stimulation), sampling time, gender, etc. all affect the concentration of ACS-related biomarkers in saliva.

Saliva and chronic kidney disease

Proteins in saliva are manipulated by distant tumor tissue, and this possible mechanism requires more research to confirm. However, from another perspective, saliva can reflect dental conditions, and dental diseases are actually related to diseases of other organs and systems. This can help people understand and accept the concept of "saliva related to systemic diseases" from one side.

A study published online March 17, 2009 in the journal Nephrol Dial Transplant confirmed that dental calculus is associated with mineral metabolic disorders and chronic kidney disease, the severity of calculus and chronic kidney disease. The severity is related. In addition, the content of calcium, phosphorus, magnesium and other elements in saliva and urea, creatinine levels, and oral pH have been altered in children with chronic kidney disease. The study in Jerusalem concluded the analysis of saliva samples and calculus scores in 74 children with chronic kidney disease, suggesting that saliva, which is closely related to dental disease, is likely to reflect the progression of other diseases.

Germany IBL has developed a series of ELISA detection reagents for the detection of human adrenal cortex technology, estrogen, progesterone and testosterone by saliva. These reagents have been widely used in Europe and other developed countries where human care is generally promoted. Applications will also become more common.