scholarly journals Salivary amylase gene copy number and its association with fasting and postprandial glucose response

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Mary Farrell ◽  
Emily Sonestedt ◽  
Anne Raben ◽  
Juscelino Tovar ◽  
Stina Ramne ◽  
...  
Keyword(s):  
Observational Study ◽  
Copy Number ◽  
Fasting Glucose ◽  
Postprandial Glucose ◽  
Gene Copy ◽  
Amylase Gene ◽  
Salivary Amylase ◽  
Glucose Levels ◽  
Copy Numbers ◽  
Meal Study

AbstractIntroductionWhen compared to other primates, humans elicit a large variation in the copy number for the salivary amylase gene, AMY1. This variation can range from 2 to 17 copies. The AMY1 gene is responsible for coding for salivary amylase, an enzyme needed to catalyze the hydrolysis of starch molecules into smaller sugars. AMY1 copy number correlates with the amount and activity of salivary amylase. Few studies have investigated the effect of amylase copy number on fasting and postprandial glucose levels. The aim was first to investigate the association between AMY1 copy numbers and fasting glucose in an observational study, and secondly to investigate the difference in postprandial effect of high-starch meals in individuals with either high or low AMY1 copy numbers.Materials and methodsFor the observational study, we used data from 436 participants from the Malmö Offspring Study (MOS) cohort whom have been genotyped for AMY1. For the meal study (conducted during May 2019), we used genotype-based-recall to recruit 24 participants from the observational study of the MOS cohort: 12 with low AMY1 copy number (from the lowest 20%) and 12 with high AMY1 copy numbers (from the highest 20%). Each subject will be served a breakfast meal of white wheat bread on two separate test days: one containing 40 g and the other containing 80 g of carbohydrates (mainly starch). Blood samples will then be taken at various time points to investigate postprandial glucose and insulin responses.ResultsWhen using linear regression analyses adjusting for age and sex, no significant association between AMY1 copy number and fasting glucose was observed (p = 0.23). However, there was a difference (p = 0.05) in fasting glucose levels between the lowest (2–4 copy numbers: 5.31 mmol/L; 95% CI: 5.13–5.50) and highest (10–16 copy numbers: 5.57 mmol/L; 95% CI: 5.39–5.75) copy number groups. The results for the meal study will be obtained in June 2019 and be presented at the conference.DiscussionOur findings of higher fasting glucose among the group with more than 10 AMY1 copy numbers is the first study to find this and needs to be replicated in other populations.

scholarly journals Effect of AMY1 copy number variation and various doses of starch intake on glucose homeostasis: data from a cross-sectional observational study and a crossover meal study

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Mary Farrell ◽  
Stina Ramne ◽  
Phébée Gouinguenet ◽  
Louise Brunkwall ◽  
Ulrika Ericson ◽  
...  
Keyword(s):  
Observational Study ◽  
Gut Microbiota ◽  
Glucose Homeostasis ◽  
Copy Number ◽  
Fasting Glucose ◽  
Postprandial Glucose ◽  
Interaction Effects ◽  
Microbiota Composition ◽  
Gut Microbiota Composition ◽  
Meal Study

Abstract Background Copy number (CN) variation (CNV) of the salivary amylase gene (AMY1) influences the ability to digest starch and may influence glucose homeostasis, obesity and gut microbiota composition. Hence, the aim was to examine the association of AMY1 CNV with fasting glucose, BMI, and gut microbiota composition considering habitual starch intake and to investigate the effect of AMY1 CNV on the postprandial response after two different starch doses. Methods The Malmö Offspring Study (n = 1764, 18–71 years) was used to assess interaction effects between AMY1 CNV (genotyped by digital droplet polymerase chain reaction) and starch intake (assessed by 4-day food records) on fasting glucose, BMI, and 64 gut bacteria (16S rRNA sequencing). Participants with low (≤ 4 copies, n = 9) and high (≥ 10 copies, n = 10) AMY1 CN were recruited for a crossover meal study to compare postprandial glycemic and insulinemic responses to 40 g and 80 g starch from white wheat bread. Results In the observational study, no overall associations were found between AMY1 CNV and fasting glucose, BMI, or gut microbiota composition. However, interaction effects between AMY1 CNV and habitual starch intake on fasting glucose (P = 0.03) and BMI (P = 0.05) were observed, suggesting inverse associations between AMY1 CNV and fasting glucose and BMI at high starch intake levels and positive association at low starch intake levels. No associations with the gut microbiota were observed. In the meal study, increased postprandial glucose (P = 0.02) and insulin (P = 0.05) were observed in those with high AMY1 CN after consuming 40 g starch. This difference was smaller and nonsignificant after consuming 80 g starch. Conclusions Starch intake modified the observed association between AMY1 CNV and fasting glucose and BMI. Furthermore, depending on the starch dose, a higher postprandial glucose and insulin response was observed in individuals with high AMY1 CN than in those with low AMY1 CN. Trial registration ClinicalTrials.gov, NCT03974126. Registered 4 June 2019—retrospectively registered.

scholarly journals Pretreatment Prevotella-to-Bacteroides ratio and salivary amylase gene copy number as prognostic markers for dietary weight loss

2020 ◽  
Vol 111 (5) ◽  
pp. 1079-1086 ◽  
Author(s):  
Mads F Hjorth ◽  
Lars Christensen ◽  
Thomas M Larsen ◽  
Henrik M Roager ◽  
Lukasz Krych ◽  
...  
Keyword(s):  
Weight Loss ◽  
Weight Change ◽  
Copy Number ◽  
Gene Copy Number ◽  
Diet Group ◽  
Gene Copy ◽  
Whole Grain ◽  
Amylase Gene ◽  
Salivary Amylase ◽  
To Receive

ABSTRACT Background The inconsistent link observed between salivary amylase gene copy number (AMY1 CN) and weight management is likely modified by diet and microbiome. Objective Based on analysis of a previously published study, we investigated the hypothesis that interaction between diet, Prevotella-to-Bacteriodes ratio (P/B ratio), and AMY1 CN influence weight change. Methods Sixty-two people with increased waist circumference were randomly assigned to receive an ad libitum New Nordic Diet (NND) high in dietary fiber, whole grain, intrinsic sugars, and starch or an Average Danish (Western) Diet (ADD) for 26 weeks. All foods were provided free of charge. Before subjects were randomly assigned to receive the NND or ADD diet, blood and fecal samples were collected, from which AMY1 CN and P/B ratio, respectively, were determined. Body weight change was described by using linear mixed models, including biomarker [log10(P/B ratio) and/or AMY1 CN] diet-group interactions. Results Baseline means ± SDs of log10(P/B ratio) and AMY1 CN were −2.1 ± 1.8 and 6.6 ± 2.4, respectively. Baseline P/B ratio predicted a 0.99-kg/unit (95% CI: 0.40, 1.57; n = 54; P < 0.001) higher weight loss for those subjects on the NND compared with those on the ADD diet, whereas AMY1 CN was not found to predict weight loss differences between the NND and ADD groups [0.05 kg/CN (95% CI: −0.40, 0.51; n = 54; P = 0.83)]. However, among subjects with low AMY1 CN (<6.5 copies), baseline P/B ratio predicted a 2.12-kg/unit (95% CI: 1.37, 2.88; n = 30; P < 0.001) higher weight loss for the NND group than the ADD group. No such differences in weight loss were found among subjects in both groups with high AMY1 CN [−0.17 kg/unit (95% CI: −1.01, 0.66; n = 24; P = 0.68)]. Conclusions The combined use of low AMY1 CN and pretreatment P/B ratio for weight loss prediction led to highly individualized weight loss results with the introduction of more fiber, whole grain, intrinsic sugars, and starch in the diet. These preliminary observations suggest that more undigested starch reaches the colon in individuals with low AMY1 CN, and that the fate of this starch depends on the gut microbiota composition. This trial was registered at clinicaltrials.gov as NCT01195610.

scholarly journals No Evidence for Association of BMI with Salivary Amylase Gene Copy Number in the UK 1958 Birth Cohort

Obesity ◽  
2019 ◽  
Vol 27 (9) ◽  
pp. 1533-1538 ◽  
Author(s):  
Nzar A. A. Shwan ◽  
John A. L. Armour
Keyword(s):  
Birth Cohort ◽  
Copy Number ◽  
Gene Copy Number ◽  
Gene Copy ◽  
Amylase Gene ◽  
Salivary Amylase ◽  
The Uk

scholarly journals Human Salivary Amylase Gene Copy Number Impacts Oral and Gut Microbiomes

2019 ◽  
Vol 25 (4) ◽  
pp. 553-564.e7 ◽  
Author(s):  
Angela C. Poole ◽  
Julia K. Goodrich ◽  
Nicholas D. Youngblut ◽  
Guillermo G. Luque ◽  
Albane Ruaud ◽  
...  
Keyword(s):  
Copy Number ◽  
Gene Copy Number ◽  
Gene Copy ◽  
Amylase Gene ◽  
Salivary Amylase

scholarly journals Salivary Amylase Gene Copy Number Is Associated with the Obesity and Inflammatory Markers in Children

2020 ◽  
Vol Volume 13 ◽  
pp. 1695-1701 ◽  
Author(s):  
Vaithinathan Selvaraju ◽  
Chandra MK Venkatapoorna ◽  
Jeganathan R Babu ◽  
Thangiah Geetha
Keyword(s):  
Copy Number ◽  
Inflammatory Markers ◽  
Gene Copy Number ◽  
Gene Copy ◽  
Amylase Gene ◽  
Salivary Amylase

Abstract P613: Absolute Gene Quantification Of Intrarenal Renin-angiotensin System Components Using Droplet Digital PCR Analysis

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Ryousuke Satou ◽  
Akemi Katsurada ◽  
Kayoko Miyata ◽  
Andrei Derbenev ◽  
Andrea Zsombok
Keyword(s):  
Copy Number ◽  
System Analysis ◽  
Renin Angiotensin System ◽  
Digital Pcr ◽  
Droplet Digital Pcr ◽  
Gene Copy ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Copy Numbers ◽  
Intrarenal Ras

The intrarenal renin-angiotensin system (RAS) has been shown to play crucial roles in the development of hypertension and RAS associated kidney injury including diabetic nephropathy. Although some circulating RAS components are filtered into kidneys and contribute to the regulation of intrarenal RAS activity, evaluating expression levels of RAS components in the kidney is important to elucidate the mechanisms underlying intrarenal RAS activation. Digital PCR is a new technique that has been established to quantify absolute target gene levels, which allows for comparisons of different gene levels. Thus, this study was performed to establish profiles of absolute gene copy numbers for intrarenal RAS components in wild-type (WT) rats, WT and streptozotocin (STZ)-induced diabetic mice. Male Sprague-Dawley rats (N=5) and male C57BL/6J mice were used in this study. The mice were subjected to either control (N=5) or STZ (200 mg/kg, N=4) injection. Seven days after STZ injection, copy numbers of renal cortical angiotensinogen (AGT), angiotensin-converting enzyme (ACE), ACE2, angiotensin type 1 receptor a (AT1a), and AT2 mRNA were determined by a droplet digital PCR. Since (pro)renin proteins produced by juxtaglomerular cells are secreted to circulating system, analysis of renin mRNA was excluded from this evaluation. In the renal cortex of WT rats, the copy number of AGT was higher than other measured RAS components (AGT: 719.2±46.6, ACE: 116.0±14.9, ACE2: 183.6±21.5, AT1a: 196.0±25.2 copies in 1 ng total RNA). AT2 levels were lower than other components (0.068±0.01 copies). In WT mice, ACE exhibited the highest copy number in the components (AGT: 447.2±29.0, ACE: 1662.4±61.2, ACE2: 676.8±41.5, AT1a: 867.0±16.8, AT2: 0.049±0.01 copies). Although STZ-induced diabetes did not change ACE2 and AT1a, ACE levels were reduced (765.5±98.1 copies) and AT2 levels were augmented (0.10±0.01 copies) as previously demonstrated. Accordingly, the absolute quantification by digital PCR established precise gene profiles of intrarenal RAS components, which will provide rationales for targeting the each component in future studies. Furthermore, the results indicate that the high sensitive assay accurately quantifies rare target genes including intrarenal AT2.

scholarly journals Photo-Induced Electron Transfer Real-Time PCR for Detection ofPlasmodium falciparum plasmepsin 2Gene Copy Number

2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Samaly Santos Souza ◽  
Mariangela L'Episcopia ◽  
Carlo Severini ◽  
Venkatachalam Udhayakumar ◽  
Naomi W. Lucchi
Keyword(s):  
Electron Transfer ◽  
Real Time ◽  
Real Time Pcr ◽  
Copy Number ◽  
Gene Copy ◽  
Content Type ◽  
Copy Numbers ◽  
Ofplasmodium Falciparum ◽  
Photo Induced Electron Transfer ◽  
Gene Copy Numbers

ABSTRACTPiperaquine is an important partner drug used in artemisinin-based combination therapies (ACTs). An increase in theplasmepsin 2and3gene copy numbers has been associated with decreased susceptibility ofPlasmodium falciparumto piperaquine in Cambodia. Here, we developed a photo-induced electron transfer real-time PCR (PET-PCR) assay to quantify the copy number of theP. falciparumplasmepsin 2gene (PfPM2) that can be used in countries whereP. falciparumis endemic to enhance molecular surveillance.

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