建议低唾液淀粉酶活性(SAA)和冷却或炒熟淀粉会降低其消化率和血糖指数。
我们确定了SAA的作用,冷却,和唾液淀粉酶(AMY1)中的单核苷酸多态性(SNP),胰淀粉酶(AMY2A,AMY2B),麦芽糖酶-葡糖淀粉酶(MGAM),蔗糖酶-异麦芽糖酶(SI)基因对熟米饭淀粉消化率和血糖指数的影响。
健康受试者[飞行员,n=12;主,n=20,低SAA(<50U/mL),andn=20withhigh-SAA(>105U/mL)]consumedtestmealscontaining25g(pilot)or50g(main)availablecarbodicatacontractresearchorganizationusingopen-label(pilot)orassessor-blinded(main),随机化,交叉,拉丁方设计(试用注册:NCT03667963)。中试测试餐是葡萄糖,新鲜煮熟的精米,煮熟的米饭冷却过夜,炒热饭,或者炒冷米饭。主要试验测试餐是葡萄糖,葡萄糖加10克乳果糖,普通热饭,或者普通的冷米饭。在两个试验中,空腹和每隔2小时测量血糖。在主要试验中,空腹和每小时测量呼吸氢,持续6小时,以估计体内淀粉的消化率。通过重复测量ANOVA分析数据,以了解温度和炒制的主要影响(中试)或SAA和温度的主要影响(主要试验)及其相互作用。分别评估了24种单核苷酸多态性(SNP)的影响。如果差异的95%CI在葡萄糖反应/血糖指数的比较平均值的±20%或消化率的±7%内,则认为平均值相等。
试点:温度和炒菜都不会显着影响葡萄糖增量AUC(主要终点,n=12)。主要:平均±SEM血糖指数(主要终点,n=40)与高SAA相比,低SAA相当(73±3vs.75±4)和冷米饭与热米饭(75±3vs.70±3)。与高SAA相比,低SAA的估计淀粉消化率(n=39)相当(95%±1%与92%±1%)和热饭与冷饭相比(94%±1%与93%±1%)。对于任何SNP,在基因型和淀粉消化率或血糖指数之间没有观察到有意义的关联。
结果不支持低SAA,冷却,淀粉消化酶的常见遗传变异会影响煮熟的米饭的血糖指数或体内碳水化合物消化率。该试验在clinicaltrials.gov注册为NCT03667963。
It was suggested that low salivary-amylase activity (SAA) and cooling or stir-frying cooked starch decreases its digestibility and glycemic index.
We determined the effects of SAA, cooling, and single-nucleotide polymorphisms (SNPs) in the salivary amylase (AMY1), pancreatic amylase (AMY2A, AMY2B), maltase-glucoamylase (MGAM), and sucrase-isomaltase (SI) genes on starch digestibility and glycemic index of cooked polished rice.
Healthy subjects [pilot, n = 12; main, n = 20 with low-SAA (<50 U/mL), and n = 20 with high-SAA (>105 U/mL)] consumed test meals containing 25 g (pilot) or 50 g (main) available carbohydrate at a contract research organization using open-label (pilot) or assessor-blinded (main), randomized, crossover, Latin-square designs (trial registration: NCT03667963). Pilot-trial test meals were dextrose, freshly cooked polished rice, cooked rice cooled overnight, stir-fried hot rice, or stir-fried cold rice. Main-trial test meals were dextrose, dextrose plus 10 g lactulose, plain hot rice, or plain cold rice. In both trials, blood glucose was measured fasting and at intervals over 2 h. In the main trial, breath hydrogen was measured fasting and hourly for 6 h to estimate in vivo starch digestibility. Data were analyzed by repeated-measures ANOVA for the main effects of temperature and stir-frying (pilot trial) or the main effects of SAA and temperature (main trial) and their interactions. Effects of 24 single nucleotide polymorphisms (SNPs) were assessed separately. Means were considered to be equivalent if the 95% CI of the differences were within ±20% of the comparator mean for glucose response/glycemic index or ±7% for digestibility.
Pilot: neither temperature nor stir-frying significantly affected glucose incremental AUC (primary endpoint, n = 12). Main: mean ± SEM glycemic index (primary endpoint, n = 40) was equivalent for low-SAA compared with high-SAA (73 ± 3 vs. 75 ± 4) and cold rice compared with hot rice (75 ± 3 vs. 70 ± 3). Estimated starch digestibility (n = 39) was equivalent for low-SAA compared with high-SAA (95% ± 1% vs. 92% ± 1%) and hot rice compared with cold rice (94% ± 1% vs. 93% ± 1%). No meaningful associations were observed between genotypes and starch digestibility or glycemic index for any of the SNPs.
The results do not support the hypotheses that low-SAA, cooling, and common genetic variations in starch-digesting enzymes affect the glycemic index or in vivo carbohydrate digestibility of cooked polished rice. This trial was registered at clinicaltrials.gov as NCT03667963.