Salivary alpha-amylase as a non-invasive biomarker for the sympathetic nervous system: Current state of research

Fitness level impacts salivary antimicrobial protein responses to a single bout of cycling exercise

“…While exercise increased the concentration and/or secretion of all sAMPs, only α--amylase was sensitive to the workload encountered. This was expected as salivary α--amylase has been used as a biomarker of sympathetic nervous system activation (Papacosta and Nassis 2011), with a number of studies showing increased α--amylase levels in response to a variety of acute stressors such as exercise, academic examinations, medical procedures, and laboratory--based stress tasks (Nater and Rohleder 2009). Further, salivary α--amylase correlates with the anaerobic threshold (Calvo et al 1997), indicating that blood lactate and α--amylase responses to exercise are tightly linked.…”

Changes in the salivary protein profile of morbidly obese women either previously subjected to bariatric surgery or not

“…Salivary alpha-amylase abundance has also been suggested as a marker of stress and sympathetic nervous system activity [31]. Some studies suggest that obesity is associated with increases [20], whereas weight loss is related to decreases in sympathetic nervous system activity [42].…”

“…Although a link between this protein and taste perception has not been reported, it is involved in carbohydrate digestion and absorption, having also a role in the perception of starchy foods [25]. The potential interest in examining alpha-amylase in the study of obesity is increased by the known relation between this protein's concentration levels and the activity of the sympathetic nervous system [31], which is involved in energy balance and implicated in the development and maintenance of obesity [42]. Despite what has been stated above, a limited number of studies on the biochemical characteristics of saliva in obese individuals have been carried out.…”

The effects of autonomy support on salivary alpha-amylase: The role of individual differences

“…Although the vignette method has several strengths, such as minimizing the effects of physical activity on the physiological measure sAA (see for example Nater and Rohleder, 2009), future research might also test the relationship examined here in a reallife setting, in order to strengthen the generalizability of the results. Additionally, future studies employing vignettes could improve the methodological procedure by for example testing whether individuals differ in their abilities to imagine the scenarios, and whether this influences the reported results.…”

“…The response of the SNS is very quick: it activates pre-ganglionic sympathetic nerves, located in the locus coeruleus. This mechanism triggers the release of norepinephrine and epinephrine from the adrenal medulla, which in turn triggers several peripheral reactions, such as an increase in salivary alpha-amylase (sAA), heart rate, and blood pressure, which can be measured relatively promptly after the onset of the stressor (Ali and Pruessner, 2012;Chrousos, 2009;Nater and Rohleder, 2009). In recent research, sAA has been shown to reliably reflect the short-term reaction to different stressors in experimental situations (Allwood et al, 2011;Nater et al, 2005;Nater and Rohleder, 2009;van Stegeren et al, 2006;Skoluda et al, 2015).…”