Chewing bread: impact on alpha-amylase secretion and oral digestion

The effect of the gastrointestinal hormone, cholecystokinin-pancreozymin (CCK-PZ), on the flux of alpha-amylase across the basolateral surface of the pancreas into interstitial fluid was measured by following its appearance in the medium bathing whole rabbit pancreas in organ culture. CCK-PZ increased the rate of amylase release by about an order of magnitude for the maximum applied dose. The response was only observed at concentrations of CCK-PZ that were supramaximal for ductal enzyme secretion (320 pmol/l to 10 nmol/l). Over this range, amylase secretion into the bath varied widely with dose, whereas that into the duct remained relatively unchanged. These observations, in conjunction with others, suggest that the acinar cell, and not the duct system, is the direct source of this amylase and that there is a natural secretion of digestive enzyme from the acinar cell in the endocrine direction that is augmented by CCK-PZ or a homologous peptide.

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Altered Salivary Alpha-Amylase Secretion in Patients with Ulcerative Colitis

Gastroenterology Research and Practice ◽

10.1155/2018/4203737 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Zhuoni Xu ◽

Baoping Wei ◽

Yanting Qiu ◽

Tao Zhang

Keyword(s):

Ulcerative Colitis ◽

Nervous System ◽

Copy Number ◽

Nervous Activity ◽

Alpha Amylase ◽

Gene Copy ◽

Anxiety And Depression ◽

Amylase Secretion ◽

Salivary Alpha Amylase ◽

Sympathetic Nervous

Purpose. Patients with ulcerative colitis (UC) frequently present with psychological disturbances as well as dysfunctions of autonomic nervous system (ANS). Salivary alpha-amylase (sAA) secretion is predominantly controlled by sympathetic nervous activity, while salivary fluid secretion is by parasympathetic nervous activity. Thus, it is speculated that alterations of salivary secretion may be addressed in UC populations. Methods. Thirty-five UC patients as well as 32 age- and sex-matched healthy controls were enrolled. Saliva samples before and after citric acid stimulation were collected from each participant, and salivary flow rate (SFR) was calculated accordingly. Western blotting and quantitative PCR were applied to measure the sAA level and sAA gene (AMY1) copy number, respectively. The psychological disorders, anxiety and depression, were evaluated by the scoring system of Hospital Anxiety and Depression Scale (HADS) for each participant. Results. We observed robustly increased prevalence of anxiety (p<0.001) as well as depression (p<0.001) in UC patients relative to controls. Interestingly, we detected elevated basal (p=0.015) and stimulated (p=0.021) sAA levels in the UC populations compared to controls. However, no differences were found for basal (p=0.643) or stimulated (p=0.402) SFR between the two study groups. Besides, AMY1 gene copy number was comparable between UC patients and controls. Conclusions. Our results reveal an overactivity of the sympathetic nervous system and a normal activity of the parasympathetic nervous system in the UC population.

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The effect of oral stimulation on human parotid salivary flow rate and alpha-amylase secretion

Physiology & Behavior ◽

10.1016/0031-9384(87)90355-6 ◽

1987 ◽

Vol 41 (3) ◽

pp. 209-217 ◽

Cited By ~ 71

Author(s):

Deborah A. Froehlich ◽

Rose Marie Pangborn ◽

John R. Whitaker

Keyword(s):

Flow Rate ◽

Salivary Flow ◽

Salivary Flow Rate ◽

Alpha Amylase ◽

Amylase Secretion ◽

Oral Stimulation

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Identification and optimization of PrsA in Bacillus subtilis for improved yield of amylase

Microbial Cell Factories ◽

10.1186/s12934-019-1203-0 ◽

2019 ◽

Vol 18 (1) ◽

Cited By ~ 6

Author(s):

Ane Quesada-Ganuza ◽

Minia Antelo-Varela ◽

Jeppe C. Mouritzen ◽

Jürgen Bartel ◽

Dörte Becher ◽

...

Keyword(s):

Bacillus Subtilis ◽

Stress Response ◽

Alpha Amylase ◽

Amylase Secretion ◽

Secretion Stress ◽

Final Yield ◽

Alpha Amylases

Abstract Background PrsA is an extracytoplasmic folding catalyst essential in Bacillus subtilis. Overexpression of the native PrsA from B. subtilis has repeatedly lead to increased amylase yields. Nevertheless, little is known about how the overexpression of heterologous PrsAs can affect amylase secretion. Results In this study, the final yield of five extracellular alpha-amylases was increased by heterologous PrsA co-expression up to 2.5 fold. The effect of the overexpression of heterologous PrsAs on alpha-amylase secretion is specific to the co-expressed alpha-amylase. Co-expression of a heterologous PrsA can significantly reduce the secretion stress response. Engineering of the B. licheniformis PrsA lead to a further increase in amylase secretion and reduced secretion stress. Conclusions In this work we show how heterologous PrsA overexpression can give a better result on heterologous amylase secretion than the native PrsA, and that PrsA homologs show a variety of specificity towards different alpha-amylases. We also demonstrate that on top of increasing amylase yield, a good PrsA–amylase pairing can lower the secretion stress response of B. subtilis. Finally, we present a new recombinant PrsA variant with increased performance in both supporting amylase secretion and lowering secretion stress.

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RECONSTITUTION OF DIFFERENT SIGNAL PEPTIDES FOR ENHANCED THERMOSTABLE ALPHA AMYLASE SECRETION IN Bacillus subtilis

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/1/9698 ◽

2018 ◽

Vol 56 (1) ◽

pp. 7 ◽

Cited By ~ 1

Author(s):

Nguyen Thị Da ◽

Tran Dinh Man ◽

Nguyen Kim Thoa

Keyword(s):

Molecular Weight ◽

Bacillus Subtilis ◽

Bacillus Cereus ◽

Bacillus Licheniformis ◽

Signal Peptide ◽

Amylase Activity ◽

Alpha Amylase ◽

Amylase Secretion ◽

Signal Peptides ◽

Extracellular Amylase

Three signal peptides of alpha amylase genes of three isolated strains that were Bacillus licheniformis DA23, Bacillus subtilis D5-2, Bacillus cereus CN1-5 were successfully sequenced. Three predicted “Sec – type” signal peptides have a length varying from 27 (CN1-5) to 33 residues (D5-2). The secretion of alpha amylase of the recombination B. subtilis 168MPgrac strain (pHV33–PgracAmy3BT2) with 71.4U/ml was larger than that of 168MPamy with 53.2U/ml. Base on analyzed rerults of PAGE and zymogram about molecular weight, alpha amylases in both strains were the same size, nearly 58kDa. The extracellular amylase activity of signal peptide SsubtilisD5.2 in 168M was highest with 76.4±4.3 U/ml in four signal peptide targets.

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Dynamics of diurnal cortisol and alpha-amylase secretion and their associations with PTSD onset in recent interpersonal trauma survivors

Psychological Medicine ◽

10.1017/s0033291721004050 ◽

2021 ◽

pp. 1-11

Author(s):

Kerry L. Kinney ◽

Uma Rao ◽

Brooklynn Bailey ◽

Natalie Hellman ◽

Chris Kelly ◽

...

Keyword(s):

Stress Response ◽

Childhood Trauma ◽

Symptom Severity ◽

Trauma Exposure ◽

Interpersonal Trauma ◽

Alpha Amylase ◽

Trauma Survivors ◽

Amylase Secretion ◽

Diurnal Cortisol ◽

Response Systems

Abstract Background Dysfunction in major stress response systems during the acute aftermath of trauma may contribute to risk for developing posttraumatic stress disorder (PTSD). The current study investigated how PTSD diagnosis and symptom severity, depressive symptoms, and childhood trauma uniquely relate to diurnal neuroendocrine secretion (cortisol and alpha-amylase rhythms) in women who recently experienced interpersonal trauma compared to non-traumatized controls (NTCs). Method Using a longitudinal design, we examined diurnal cortisol and alpha-amylase rhythms in 98 young women (n = 57 exposed to recent interpersonal trauma, n = 41 NTCs). Participants provided saliva samples and completed symptom measures at baseline and 1-, 3-, and 6-month follow-up. Results Multilevel models (MLMs) revealed lower waking cortisol predicted the development of PTSD in trauma survivors and distinguished at-risk women from NTCs. Women with greater childhood trauma exposure exhibited flatter diurnal cortisol slopes. Among trauma-exposed individuals, lower waking cortisol levels were associated with higher concurrent PTSD symptom severity. Regarding alpha-amylase, MLMs revealed women with greater childhood trauma exposure exhibited higher waking alpha-amylase and slower diurnal alpha-amylase increase. Conclusions Results suggest lower waking cortisol in the acute aftermath of trauma may be implicated in PTSD onset and maintenance. Findings also suggest childhood trauma may predict a different pattern of dysfunction in stress response systems following subsequent trauma exposure than the stress system dynamics associated with PTSD risk; childhood trauma appears to be associated with flattened diurnal cortisol and alpha-amylase slopes, as well as higher waking alpha-amylase.

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