Attenuated acute salivary α-amylase responses to gustatory stimulation with citric acid in thin children

Abstract

Salivary a-amylase (sAA) is responsible for the 'pre-digestion' of starch in the oral cavity and accounts for up to 50 % of salivary protein in human saliva. An accumulating body of literature suggests that sAA is of nutritional importance; however, it is still not clear how sAA is related to individual's nutritional status. Although copy number variations (CNV) of the salivary amylase gene (AMY1) are associated with variation in sAA levels, a significant amount of sAA variation is not explained by AMY1 CNV. To measure sAA responses to gustatory stimulation with citric acid, we used sAA ratio (the ratio of stimulated sAA levels to those of resting sAA) and investigated acute sAA responses to citric acid in children with normal (Normal-BMI, n 22) and low (Low-BMI, n 21) BMI. The AMY1 gene copy number was determined by quantitative PCR. We, for the first time, demonstrated attenuated acute sAA responses (decreased sAA ratio) to gustatory stimulation in Low-BMI (thinness grade 3) children compared with the Normal-BMI children, which suggest that sAA responses to gustatory stimulation may be of nutritional importance. However, child's nutritional status was not directly related to their resting or stimulated sAA levels, and it was not associated with AMY1 gene copy number. Finally, AMY1 CNV might influence, but did not eventually determine, sAA levels in children.

Abnormalities in acute salivary biochemical characteristic responses to gustatory stimulation with citric acid in chronic non‐atrophic gastritis

“…It is well known that gustatory stimulation with acid promotes salivary secretion, so acute responses of salivary glands induced by acid stimulation can provide more pathophysiological information compared with sole assessment of resting saliva. For example, our previous study found that acute sAA activity response to acid stimulation was reduced in low‐BMI children compared with normal‐BMI children; however, no relationship of nutritional status with sAA activities under both resting and stimulated conditions was found . Hence, our present study focused on acute salivary biochemical characteristic responses to acid stimulation, in order to explore more pathophysiological information of CNAG.…”

“…Our data revealed that attenuated acute sAA activity response to acid stimulation reflects that the extent of sAA response to diet feeding may be decreased and then affect CNAG patients' nutritional status. This suggests that sAA response to acid stimulation may be of nutritional importance, consistent with our previous results …”

Gender differences in the saliva of young healthy subjects before and after citric acid stimulation

“…Fifty-five subjects were enrolled, ranging in age from 21 As determined by PD sampling, compared to baseline, the SFR, pH, sAA activity and sTAPM increased significantly (p < 0.05) for both genders after the initial acid stimulation (Table 1). In the PD samples, the mean pH values of females both before and after acid stimulation were significantly lower than males (p < 0.01).…”

“…Furthermore, gustatory stimulation, especially acid stimulation, plays a major role in elevated SFR and altered salivary composition [10,11,21,22].…”

Salivary Diagnostics in Pediatrics: Applicability, Translatability, and Limitations

“…These components, whether molecule, transcript, protein, metabolite, or microbe, are reflective of both the age and developmental stage of the individual (25–27). For example, salivary enzymes, such as amylase, are known to increase from early infancy through adolescence, ultimately peaking in adulthood (28–31). Salivary electrolyte levels are also known to vary with age.…”