Effects of &amp;lt;i&amp;gt;γ&amp;lt;/i&amp;gt;-Polyglutamic Acid on Blood Glucose and Caecal Short Chain Fatty Acids in Adult Male Mice

Tamura, Motoi; Hori, Shingo; Inose, Atsuko; Kobori, Masuko

doi:10.4236/fns.2020.111002

Cited by 7 publications

(6 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, a hyperglycemia inhibitor that consists primarily of the γ-PGA potassium salt has been patented [10]. Tamura et al also reported that co-administration of γ-PGA suppresses the initial rise in blood glucose levels after starch loading in mice [18]. Therefore, the high-γ-PGA natto-induced suppression of blood glucose elevation in this study might have been affected by γ-PGA, the content of which was markedly different between the high-and low-γ-PGA natto meals.…”

Section: Discussionmentioning

confidence: 99%

The Possibility of Suppression of Increased Postprandial Blood Glucose Levels by Gamma-Polyglutamic Acid-Rich Natto in the Early Phase after Eating: A Randomized Crossover Pilot Study

et al. 2020

View full text Add to dashboard Cite

The natto containing high levels of gamma-polyglutamic acid (γ-PGA) was recently developed. We investigated the effect of γ-PGA-rich natto consumption on postprandial glycemic excursion in humans. A randomized crossover meal test study was performed on healthy volunteers aged 20–64 years using the following test meals: (1) white rice (WR), (2) low-γ-PGA natto meal (WR + low-γ-PGA natto), and (3) high-γ-PGA natto meal (WR + high-γ-PGA natto). Blood samples were obtained at each visit before and for 120 min after loading. The incremental area under the curve (IAUC) of blood glucose and insulin levels was calculated and compared among the test meals. The blood glucose’s IAUC at 0–120 min, the primary endpoint, was 20.1% and 15.4% lower for the high- and low-γ-PGA natto meal than for the WR, with a significant difference only between the high-γ-PGA natto meal and WR (p < 0.05). The blood glucose’s IAUC at 0–15, 0–30, and 0–45 min was lower for the high-γ-PGA natto meal than for the low-γ-PGA natto meal (all p < 0.05). The possibility that high-γ-PGA natto might suppress blood glucose elevations in the early phase after eating is indicated.

show abstract

Section: Discussionmentioning

confidence: 99%

The Possibility of Suppression of Increased Postprandial Blood Glucose Levels by Gamma-Polyglutamic Acid-Rich Natto in the Early Phase after Eating: A Randomized Crossover Pilot Study

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In a human study, it was reported that a single administration of high γ-PGA natto diet lowered postprandial blood glucose level of γ-PGA more than a single administration of low γ-PGA natto diet, ( 11 ) and in a mouse study, oral administration of starch + γ-PGA significantly lowered blood glucose level than starch alone, suggesting a hypoglycemic effect of γ-PGA. ( 24 ) The low blood glucose levels in the NA group are presumably due to the hypoglycemic effect of γ-PGA.…”

Section: Discussionmentioning

confidence: 97%

High poly-γ-glutamic acid-containing natto improves lipid metabolism and alters intestinal microbiota in mice fed a high-fat diet

Tamura,

Watanabe,

Noguchi

et al. 2024

J. Clin. Biochem. Nutr.

Self Cite

View full text Add to dashboard Cite

Several beneficial effects of poly-γ-glutamic acid (γ-PGA) have been reported. To test whether natto, a fermented soy food rich in γ-PGA, can improve intestinal microbiota content and lipid metabolism in a high-fat diet, we compared the intestinal microbiota content, plasma, liver, and fecal contents, and changes in gene expression in the livers and large intestines of a group of mice fed a high-fat diet supplemented with cooked soybeans (SC group) and a group fed a high-fat diet supplemented with natto (NA group) for 42 days; high-fat diet-fed mice were used as a control (Con group). Hepatic lipid levels were significantly lower, the fecal bile acid and lipid levels were significantly greater, and the Bacteroidetes / Firmicutes ratio was significantly higher in the SC and NA groups as compared to Con group. Additionally, plasma glucose and triglyceride levels, the expression of liver fatty acid synthase, and the relative abundance of Lactobacillaceae was significantly higher in the NA group than in the Con group. Although both natto and cooked soybeans impacted the metabolic response to a high-fat diet, the addition of natto had a greater effect on glucose and lipid metabolism. γ-PGA may play an important role in natto functionality.

show abstract

“…In the animal study by Tamura et al, the inhibitory effect of γ -PGA on the blood glucose levels increased at the initial phase after starch loading [ 17 ]. γ -PGA is a viscous substance [ 3 ], and its content is approximately eight-fold higher in HPGA natto than in LPGA natto.…”

Section: Discussionmentioning

confidence: 99%

Gamma-Polyglutamic Acid-Rich Natto Suppresses Postprandial Blood Glucose Response in the Early Phase after Meals: A Randomized Crossover Study

et al. 2020

View full text Add to dashboard Cite

We evaluated the suppressive effects of high-gamma-polyglutamic acid (γ-PGA) natto on postprandial blood glucose level and insulin response. After confirming the eligibility of candidates using a pre-selective test with packaged white rice, a meal loading test including low- or high-γ-PGA natto (with 57.6 mg (LPGA) and 439.6 mg (HPGA) of γ-PGA, respectively) was conducted in men aged 20 to 70 years (n = 29) and postmenopausal women aged ≤70 years (n = 7). On each examination day, blood samples were obtained after they fasted overnight and for 120 min after test meal loading. The primary outcome of this study was the difference between the measurements of the incremental area under the curve (IAUC) for blood glucose 0 to 30 min after loading of LPGA and HPGA meals. The IAUCs for blood glucose and insulin after the HPGA meal were lower than those after the LPGA meal within 45 min (0 to 15 and 0 to 30 min: p < 0.001, 0 to 45 min: p < 0.01) and 1 h (all p < 0.001) of loading, respectively. The suppressive effects of HPGA natto on postprandial glucose response in the early phase, which possibly relates to the risk of dysglycemia and cardiovascular disease, were clarified.

show abstract

Effects of <i>γ</i>-Polyglutamic Acid on Blood Glucose and Caecal Short Chain Fatty Acids in Adult Male Mice

Cited by 7 publications

References 26 publications

The Possibility of Suppression of Increased Postprandial Blood Glucose Levels by Gamma-Polyglutamic Acid-Rich Natto in the Early Phase after Eating: A Randomized Crossover Pilot Study

The Possibility of Suppression of Increased Postprandial Blood Glucose Levels by Gamma-Polyglutamic Acid-Rich Natto in the Early Phase after Eating: A Randomized Crossover Pilot Study

High poly-γ-glutamic acid-containing natto improves lipid metabolism and alters intestinal microbiota in mice fed a high-fat diet

Gamma-Polyglutamic Acid-Rich Natto Suppresses Postprandial Blood Glucose Response in the Early Phase after Meals: A Randomized Crossover Study

Contact Info

Product

Resources

About