Serum α-amylase correlates with xerostomia in patients with primary Sjögren's disease.

Sjögren's disease is one of the most common systemic autoimmune diseases with hallmark features of sicca (dryness) symptoms of the eyes and mouth. There are a variety of ways to quantify xerostomia. α-Amylase is an enzyme secreted by the pancreas and salivary glands. While not specific to salivary glands, it may be measured as a surrogate marker of their output. Therefore, in this short investigation, we determined if there were any associations of serum α-amylase with subjective and objective markers of xerostomia. This investigation found a correlation between objective and subjective markers of xerostomia and α-amylase which suggests that measuring this analyte is a novel adjunct to qualifying xerostomia in the clinic.

Activity-Based Protein Profiling of Retaining α-Amylases in Complex Biological Samples.

Amylases are key enzymes in the processing of starch in many kingdoms of life. They are important catalysts in industrial biotechnology where they are applied in, among others, food processing and the production of detergents. In man amylases are the first enzymes in the digestion of starch to glucose and arguably also the preferred target in therapeutic strategies aimed at the treatment of type 2 diabetes patients through down-tuning glucose assimilation. Efficient and sensitive assays that report selectively on retaining amylase activities irrespective of the nature and complexity of the biomaterial studied are of great value both in finding new and effective human amylase inhibitors and in the discovery of new microbial amylases with potentially advantageous features for biotechnological application. Activity-based protein profiling (ABPP) of retaining glycosidases is inherently suited for the development of such an assay format. We here report on the design and synthesis of 1,6-epi-cyclophellitol-based pseudodisaccharides equipped with a suite of reporter entities and their use in ABPP of retaining amylases from human saliva, murine tissue as well as secretomes from fungi grown on starch. The activity and efficiency of the inhibitors and probes are substantiated by extensive biochemical analysis, and the selectivity for amylases over related retaining endoglycosidases is validated by structural studies.

α-Amylase assay with starch-iodine-sodium fluorescein-based fluorometric method in human serum samples.

A new fluorometric method was developed for the determination of α-amylase activity in human serum samples. Firstly, a saturated starch-iodine complex (SI) was prepared. The SI complex was combined with sodium fluorescein to form a starch-iodine-sodium fluorescein complex (SIF). As the SIF complex decomposes with the α-amylase enzymatic hydrolysis of starch, the intensity of its fluorescence emission increases. The α-amylase activity is determined using the increased fluorescence emission intensity following hydrolysis of the SIF complex by α-amylase. The optimum pH, optimum buffer concentration, optimum temperature, and interference effect were identified for the developed fluorometric measurement method. Under the optimum conditions, a linear calibration curve was obtained between 0.18 and 9.00 U/L for α-amylase. The α-amylase activity in the human serum sample was also determined by our prepared measurement system and compared with the result from a medical center. Both methods are in good agreement with each other. Because this newly developed fluorometric method for α-amylase activity in serum samples is inexpensive, easy to use, and carried out to detect a very low amount of human serum α-amylase with sensitivity, it can be proposed this method for alpha-amylase activity assay in all other biological samples.

Changes in Markers of Oxidative Stress and α-Amylase in Saliva of Children Associated with a Tennis Competition.

The purpose of this paper was to analyze the changes caused by a one-day tennis tournament in biomarkers of oxidative stress and α-amylase in saliva in children. The sample was 20 male active children with the following characteristics: (a) age of players = 9.46 ± 0.66 years; (b) weight = 34.8 ± 6.5 kg; (c) height = 136.0 ± 7.9 cm; (d) mean weekly training tennis = 2.9 ± 1.0 h. The tennis competition ran for one day, with four matches for each player. Data were taken from the average duration per match and the rating of perceived exertion (RPE). Four biomarkers of antioxidant status: uric acid (AU), Trolox equivalent antioxidant capacity (TEAC), ferric reducing ability of saliva (FRAS, cupric reducing antioxidant capacity (CUPRAC) and salivary alpha-amylase (sAA) as a biomarker of psychological stress were measured in saliva. The time points were baseline (at home before the tournament), pre-competition (immediately before the first match) and post-match (after each match) measurements. The four biomarkers of antioxidant status showed a similar dynamic with lower values at baseline and a progressive increase during the four matches. Overall one-day tennis competition in children showed a tendency to increase antioxidant biomarkers in saliva. In addition, there was an increase in pre-competition sAA possibly associated with psychological stress. Further studies about the possible physiological implications of these findings should be performed in the future.

The impact of high-intensity interval training exercise on breast cancer survivors: a pilot study to explore fitness, cardiac regulation and biomarkers of the stress systems.

BACKGROUND: Cardiovascular disease (CVD) remains the largest cause of death in breast cancer survivors. The aim of this study was to explore the impact of exercise intensity on aerobic fitness and autonomic cardiac regulation (heart rate variability (HRV)) and salivary biomarkers of the stress systems (HPA-axis, cortisol; sympathetic nervous system, α-amylase) and mucosal immunity (secretory(s)-IgA), markers of increased risk of CVD in breast cancer survivors. METHODS: Participants were randomly assigned to; 1) high intensity interval training (HIIT); 2) moderate-intensity, continuous aerobic training (CMIT); or 3) a wait-list control (CON) for a 12-week (36 session) stationary cycling intervention. Cardiorespiratory fitness (VO2peak), resting HRV and salivary biomarkers were measured at baseline 2-4 d pre-intervention and 2-4 d post the last exercise session. RESULTS: Seventeen participants were included in this study (62 ± 8 years, HIIT; n = 6, CMIT; n = 5, CON; n = 6). A significant improvement (p ≤ 0.05) was observed for VO2peak in the HIIT group; 19.3% (B = 3.98, 95%CI = [1.89; 4.02]) and a non-significant increase in the CMIT group; 5.6% (B = 1.96, 95%CI = [- 0.11; 4.03]), compared with a 2.6% (B = - 0.64, 95%CI = [- 2.10; 0.82]) decrease in the CON group. Post intervention improvements in HRV markers of vagal activity (log (ln)LF/HF, LnRMSSD) and sympathetic nervous system (α-amylase waking response) occurred for individuals exhibiting outlying (> 95% CI) levels at baseline compared to general population. CONCLUSION: High intensity interval training improved cardiovascular fitness in breast cancer survivors and improved cardiac regulation, and sympathetic nervous system (stress) responses in some individuals. High-intensity interval training was safe and effective for breast cancer survivors to participate in with promising results as a time efficient intensity to improve physical health and stress, reducing CVD risk. TRIAL REGISTRATION: This pilot study was retrospectively registered through the Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12620000684921 .

The effect of bergamot orange essence on anxiety, salivary cortisol, and alpha amylase in patients prior to laparoscopic cholecystectomy: A controlled trial study.

BACKGROUND AND PURPOSE: This study aimed to determine the effect of bergamot orange essence on anxiety, salivary cortisol, and alpha amylase in patients prior to laparoscopic cholecystectomy. MATERIAL AND METHODS: This clinical trial with pre-post design was conducted on 60 candidates for cholecystectomy. The participants were randomly divided into an intervention and a control group. The intervention group participants underwent aromatherapy using two drops of 3% bergamot orange essence, while the control group ones inhaled two drops of odourless grape seed oil. Anxiety mean score and salivary cortisol and alpha amylase levels were measured before and after the intervention. RESULTS: A significant difference was found between the groups regarding anxiety (F = 9.00, p = 0.004) and alpha amylase level (F = 9.46, p = 0.003) after the intervention. CONCLUSION: Bergamot orange essence decreased anxiety and salivary alpha amylase level. Therefore, this method can be used as a complementary technique to reduce patients' anxiety prior to laparoscopic cholecystectomy surgery. IRCT REGISTRATION NUMBER: IRCT20171113037428N2. It is available in following website: https://www.irct.ir/trial/27696 REGISTRATION DATE: 03/25/2018.

Salivary alpha-amylase as a stress biomarker in diseased dogs.

Salivary alpha-amylase (sAA) is a stress biomarker in human diseases, but there are no reports of sAA measurements in diseased dogs. This study measured the sAA and serum alpha-amylase (AA) levels in 16 healthy dogs and 31 diseased dogs using a kinetic enzyme assay to assess the stress status. The sAA and serum AA levels were significantly higher in the diseased dogs than in healthy dogs (p < 0.05), but there was no correlation between the 2 groups (r = 0.251, p = 0.089). This suggests that sAA can be useful as a stress biomarker in diseased dogs.

The impact of dental treatment and age on salivary cortisol and alpha-amylase levels of patients with varying degrees of dental anxiety.

BACKGROUND: The purpose of this study was to assess the salivary cortisol and salivary alpha-amylase levels in children aged between 6 and 9 years, 3 months and 1 year after the successful completion of dental treatment through either pharmacological or non-pharmacological behavior management techniques. METHODS: A total of 1567 patients aged between 6 and 9 years who had completed dental treatment were screened. A total of 703 patients who were caries free at the end of 3 months were classified based on Frankl behavior score and administered the Arabic version of the Children's Fear Survey Schedule- Dental Subscale (CFSS-DS) and accordingly allocated to one of three groups; (Phobic Patients, Anxious Patients, Control Group). A total of 183 patients met the inclusion criteria and were followed up for 1 year. A total of 151 patients completed the study. Patients' heart rate on recall, salivary cortisol and salivary amylase were compared between the groups. RESULTS: The results of the study showed that amylase and cortisol levels had a significant association with the level of dental fear. The phobic patients had the highest levels of salivary amylase and salivary cortisol levels with no significant associations observed with either heart rate or extent of dental treatment. Control and anxious patients had significantly lower amylase levels when compared to phobic patients. There was no significant difference between the salivary cortisol levels of anxious and phobic patients. These findings were replicated on 1-year recall. CONCLUSIONS: Within the limitations of this study we can conclude that salivary amylase is an indicator of of acute stress that can differentiate between anxiety and dental fear; while salivary cortisol appears to be a marker of long-term stress that lacks the sensitivity to differentiate between the two.

Inhibitory effects of pu-erh tea on alpha glucosidase and alpha amylase: a systemic review.

OBJECTIVE: Pu-erh tea was presumed to have anti-hyperglycemic effects via inhibition on alpha-amylase and alpha-glucosidase. However, no integerated literatures were published to substantiate such presumption. METHODS: Current study adopted systemic review method to validate inhibitory effects on alpha amylase and alpha-glucosidase. Five English databases (PubMed, EBSCO, SCOPUS, Cochrane Library, Web of Science) and three Chinese ones (Airti Library, CNKI Library, and Google Scholar) were searched up to 22 March 2018 for eligible literatures, using keywords of Pu-erh, Pu'er, alpha-amylase or alpha-glucosidase. RESULTS: Six studies exploring inhibitory effects on alpha-glucosidase and seven on alpha-amylase were included for systemic review. Though results showed pu-erh tea has significant inhibitory effects on alpha-amylase and alpha-glucosidase, high heterogeneity was detected among studies included. CONCLUSIONS: High heterogeneity may be due to complex alterations of chemicals under different degrees of fermentation. More future studies are required to further identify principal bioactive component(s) at work.

Impact of deep oropharyngeal suctioning on microaspiration, ventilator events, and clinical outcomes: A randomized clinical trial.

AIMS: To evaluate a deep oropharyngeal suction intervention (NO-ASPIRATE) in intubated patients on microaspiration, ventilator-associated events and clinical outcomes. DESIGN: Prospective, two-group, single-blind, randomized clinical trial. METHODS: The study was conducted between 2014 - 2017 in 513 participants enroled within 24 hr of intubation and randomized into NO-ASPIRATE or usual care groups. Standard oral care was provided to all participants every 4 hr and deep oropharyngeal suctioning was added to the NO-ASPIRATE group. Oral and tracheal specimens were obtained to quantify α-amylase as an aspiration biomarker. RESULTS: Data were analysed for 410 study completers enrolled at least 36 hr: NO-ASPIRATE (N = 206) and usual care (N = 204). Percent of tracheal specimens positive for α-amylase, mean tracheal α-amylase levels over time and ventilator-associated events were not different between groups. The NO-ASPIRATE group had a shorter hospital length of stay and a subgroup with moderate aspiration at baseline had significantly lower α-amylase levels across time. CONCLUSION: Hospital length of stay was shorter in the NO-ASPIRATE group and a subgroup of intervention participants had lower α-amylase across time. Delivery of standardized oral care to all participants may have been an intervention itself and possibly associated with the lack of significant findings for most outcomes. IMPACT: This trial compared usual care to oral care with a deep suctioning intervention on microaspiration and ventilator-associated events, as this has not been systematically studied. Further research on the usefulness of α-amylase as an aspiration biomarker and the role of oral suctioning, especially for certain populations, is indicated. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov: NCT02284178.

Low dose of carvacrol prevents rat pancreas tissue damage after L-arginine application, while higher doses cause pancreatic tissue impairment.

Carvacrol (5-isopropyl-2-methylphenol) is a biologically active monoterpene phenol abundantly present in the essential oils of many Lamiaceae aromatic/ethnomedicinal plants. Herein, we aimed to evaluate the damaging effect of carvacrol to rat pancreatic tissue, but also to assess its possible ameliorative impact on pancreatic damage induced by L-arginine. The toxic and beneficial (in a dose of 10 mg/kg) properties of carvacrol were assessed by measuring serum α-amylase and lipase activities, tissue malondialdehyde (MDA) content, and pathohistological changes in pancreatic tissue. Application of 100/500 mg/kg of carvacrol produced a significant increase in α-amylase activity, followed by inflammatory-cell infiltration and patchy interlobular edema in the pancreas. In the L-arginine-induced pancreatitis model, a dose of 10 mg/kg of carvacrol prevented an increase in α-amylase and lipase activities, and MDA formation, when compared to the animals that received L-arginine only. Animals treated with carvacrol prior to L-arginine administration displayed mild edema and inflammatory infiltration with few necrotic areas. Contrary to that, animals that received only L-arginine showed a massive leukocyte infiltrate with edema and substantial necrotic areas. In our study carvacrol showed significant protective effects and a potential to modulate leukocyte recruitment in pancreatic tissue after L-arginine injection.

Effect of a mindfulness exercise on stress in veterinary students performing surgery.

OBJECTIVE: To determine students' stress while performing surgery and evaluate the ability of a mindfulness intervention to reduce this stress. STUDY DESIGN: Quasi-experimental design. SAMPLE POPULATION: Eighteen fourth-year DVM program students (n = 9 student/group). METHODS: Utilizing a quasi-experimental design, students were randomly assigned to a control or treatment group. The treatment group performed a 5-minute breathing (mindfulness) exercise immediately prior to performing surgery. Each student provided 3 samples of saliva, at time 0, at 10 minutes before surgery, and at 10 minutes after surgery. Students' salivary cortisol and α-amylase levels were compared between groups. Students' self-reported mood measures were also correlated to levels of salivary biomarkers. RESULTS: Cortisol and α-amylase levels of students in both groups greatly exceeded normative reference groups (>90th percentile) prior to surgery and diminished to average levels (50th-60th percentile) after surgery but did not differ between groups at any time point. Immediately prior to surgery when stress values were likely to peak, salivary α-amylase levels decreased approximately 30 U/L units for students in the treatment group compared with an increase of approximately 10 U/L units for students in the control group. Students in the treatment group reported being more calm (mean [M] 2.67, SD 1.03, d = 0.75) and relaxed (M 2.33, SD 1.51, d = 0.90) than students in the control group (M 3.44, SD 1.01 and M 3.44, SD 0.88, respectively). CONCLUSION: This study provides some evidence that the mindfulness intervention temporarily decreased stress levels and improved students' sense of calmness and relaxation immediately before operating on a live animal. CLINICAL IMPACT: Students who are experiencing less stress may be less likely to commit a medical error and negatively impact animal health. This study, the first of its kind in veterinary surgery, may serve as a model for related future studies.

An Aggregation-induced Emission Probe Based on Host-Guest Inclusion Composed of the Tetraphenylethylene Motif and γ-Cyclodextrin for the Detection of α-Amylase.

α-Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α-amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non-destructive sensing of α-amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ-cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ-cyclodextrin, but the AIE residues can be released in to water after the α-amylase hydrolysing γ-cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL-1 in MES buffer with a linear range of 0-0.35 U mL-1 , having excellent selectivity to α-amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α-amylase in human serum, showing potential in point of care testing.

Taxifolin prevents postprandial hyperglycemia by regulating the activity of α-amylase: Evidence from an in vivo and in silico studies.

There has been a dramatic increase in the prevalence of diabetes mellitus (DM) and its associated complications globally. The postprandial stage of DM involves prompt elevation in the levels of blood glucose and α-amylase, a carbohydrate-metabolizing enzyme is mainly involved in the regulation of postprandial hyperglycemia. This study was designed to assess the ability of a well-known flavonoid, taxifolin (TFN), against postprandial hyperglycemia and its inhibitory effects on α-amylase activity through the assessment of therapeutic potentials of TFN in an alloxan-induced diabetic animal model. The binding potential TFN with an α-amylase receptor was also investigated through molecular dynamics (MD) simulation and docking of to compare the binding affinities and energies of TFN and standard drug acarbose (ACB) with target enzyme. TFN significantly improved the postprandial hyperglycemia, lipid profile, and serum levels of α-amylase, lipase, and C-reactive protein in a dose-dependent manner when compared with that of either DM-induced and ACB-treated alloxan-induced diabetic rats. Moreover, TFN also enhanced the anti-oxidant status and normal functioning of the liver in alloxan-induced diabetic rats more efficiently as compared to that of ACB-treated alloxan-induced diabetic rats. Therapeutic potentials of TFN were also verified by MD simulation and docking results, which exhibited that the binding energy and affinity of TFN to bind with receptor was significantly higher as compared to that of ACB. Hence, the results of this study signify that TFN might be a potent inhibitor of α-amylase that has the potential to regulate the postprandial hyperglycemia along with its anti-inflammatory and anti-oxidant properties during the treatment of DM.

Point-of-care-testing of α-amylase activity in human blood serum.

Activity of α-amylase enzyme in human serum indicates the onset of pancreatitis, mumps, cancer, stress, and depression. Herein we design and develop a biosensor for the point-of-care-testing (POCT) of α-amylase concentration in serum. The biosensor is composed of a glass substrate coated with an electrically conducting poly-aniline-emeraldine-salt (PANI-ES) film covered with starch-coated gold nanoparticles (SAuNPs). Addition of different dosage of α-amylase on the biosensor selectively depletes starch stabilized on the SAuNPs, which changes the electrical resistance of the sensor. The change in electrical resistance show a nearly linear correlation with the concentration of α-amylase in buffer, which helps the detection of unknown α-amylase activity in the blood serum. The biosensor responds in a specific manner owing to the use of selective enzymatic chemical reaction between α-amylase and starch. The pathways to SAuNP formation on PANI-ES, time-dependent starch digestion with α-amylase, and the subsequent variation in electrical response was characterized to uncover the sensing mechanism. The chloride ions and the AuNPs present catalyse the starch-amylase reaction on the PANI surface to enable a sensitive detection of α-amylase in serum (25 - 100 U/l) at a quick response time of ~60 s. Integration of the biosensor with the built-in sourcemeter and a real time display help an immediate presentation of α-amylase level in the serum, comparable to the clinically approved methodologies.

Anti-inflammatory and Antioxidant Effects of Captopril Compared to Methylprednisolone in L-Arginine-Induced Acute Pancreatitis.

BACKGROUND: Acute pancreatitis (AP) is an inflammatory disease mediated by damage in acinar cells and pancreatic inflammation with infiltration of leukocytes. The pancreatic renin-angiotensin system may play an important role in the pathogenesis of AP. AIM: The present study aimed to investigate the possible protective role of captopril (CAP), an angiotensin-converting enzyme inhibitor, in attenuating L-arginine-induced AP rat model and to elucidate the underlying molecular mechanisms. METHODS: Forty-eight adult male Wister rats were divided into four equal groups: control group (vehicle, orally for 10 days), AP group (3 g/kg L-arginine, single i.p.) on 10th day of the experiment, CAP group (50 mg/kg captopril, orally, once daily), and MP group (30 mg/kg methylprednisolone, orally, once daily). CAP and MP were administered for 10 days prior to L-arginine injection. Rats were sacrificed 24 h after arginine injection. Inflammatory biomarkers; tumor necrosis factor alpha (TNF-α) concentration, myeloperoxidase (MPO) activity, and inducible nitric oxide synthase (iNOS) gene expression were determined in pancreas. Oxidative stress biomarkers; pancreatic nitric oxide (NO) and reduced glutathione (GSH) concentrations were measured. Moreover, serum α-amylase and lipase activities were measured and histopathological studies of the pancreas were done. RESULTS: CAP group showed a significant reduction in pancreatic TNF-α concentration, MPO activity, NO concentration, and downregulation of iNOS gene expression compared to AP group. CAP group also showed a significant increase in GSH concentration with amelioration of histological changes of AP as well as MP group. CONCLUSION: Captopril treatment showed a protective and comparable effect with MP treatment in AP rat model.

Hormonal and Neuromuscular Responses to Breastfeeding: A Pilot Study.

OBJECTIVES: Difficult breastfeeding in the first weeks after birth may result in muscle tension in infants and activation of the maternal hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS). Our primary objective was to examine the feasibility of collecting neuroendocrine markers of maternal HPA axis and SNS activation (salivary cortisol and α-amylase [sAA]) and electromyographic (EMG) markers of infant distress during feeding in the first 2 weeks after birth. We also examined the relationships of these indices to each other and to mother-infant interactive behaviors during feeding. METHODS: We recruited mothers in the postpartum unit of a teaching hospital and observed a feeding in the dyad's home. Cortisol and sAA were sampled before feeding, 10 min into feeding, at feeding end, and 20 min after feeding. Infant muscle activity was recorded continuously with an EMG data logger. We used the Nursing Child Assessment Feeding Scale to measure mother-infant interaction. RESULTS: The 20 mothers reported no disruption to breastfeeding and no change in infant behavior due to collection measures. Mean cortisol levels decreased significantly; there was no significant change in sAA levels. Relationships were found between interactive behavior and trends in neuroendocrine biomarkers. Longer bursts of infant muscle activity were associated with higher levels of maternal cortisol during feeding but not mother-infant interactive behaviors. CONCLUSIONS: Maternal salivary biomarkers and their association with feeding behaviors can be a useful tool for clinical longitudinal research beginning soon after birth. Infant EMG data may be useful for assessing maternal arousal.

Clinical and neurobiological effects of aerobic exercise in dental phobia: A randomized controlled trial.

BACKGROUND: Physical activity has shown to be effective in anxiety disorders. For specific phobia, no studies are available that systematically examined the effects of an aerobic exercise intervention on phobic fear within a randomized-controlled design. Therefore, we investigated the acute effect of a standardized aerobic training on clinical symptoms of dental phobia as well as on stress-related neurobiological markers. METHODS: Within a crossover design, 30 patients with dental phobia (mean age: 34.1 years; mean score of the Dental Anxiety Scale: 18.8) underwent two minor dental interventions separated by 7 days. Dental treatment was performed after 30 min of physical activity at either 20% VO2 max (control) or 70% VO2 max (intervention), respectively. To control for habituation, patients were randomly assigned to one of the two conditions prior to the first intervention. Moreover, saliva samples were collected at five times in order to determine changes in salivary cortisol (sC) and alpha-amylase (sAA) due to treatment. RESULTS: In comparison to baseline, aerobic exercise within 70% VO2 max significantly reduced clinical anxiety and sC concentrations before, during, and after the dental treatment. In contrast, the control condition led to decreased sAA levels at different time points of measurement. Habituation occurred at the second study day, independent of the order. CONCLUSIONS: Our study provides evidence for an effect of moderate-intense exercise on clinical symptoms and sC in patients with dental phobia. Therefore, acute aerobic exercise might be a simple and low-cost intervention to reduce disorder-specific phobic fear.

Alpha-amylase serum levels in professional soccer players are not related with physical fitness.

BACKGORUND: Recent evidence has showed that serum or salivary values of α-amylase predict endurance running performance. In this study we investigate whether serum α-amylase concentration may be associated with training status during a competitive season and after a detraining period in professional soccer players. METHODS: The study population consisted in 15 male professional soccer players from an Italian major league team (age [mean±SD] 27±5 years, weight 76.9±4.1 kg, height 1.82±0.05 m). Serum α-amylase levels were measured 3 times during the last part of a competitive season (January, March and May) and just before preseason training (July). RESULTS: Metabolic and cardiovascular fitness of soccer players was improved during the last part of the season. The levels of α-amylase did not change significantly throughout the study period (χ2=7.331, P=0.062), nor they were found to be associated with variation of physical fitness and training status. CONCLUSIONS: The α-amylase fluctuations throughout a competitive season and after vacation time were meaningless in professional soccer players. No significant associations with physical fitness variations could be observed. These results suggest that α-amylase concentration may be a useful parameter for identifying individual inclination to endurance exercise, but not for predicting actual training status.