Mulberry leaf extract displays antidiabetic activity in db/db mice via Akt and AMP-activated protein kinase phosphorylation

  • Ui-Jin Bae Chonbuk National University Medical School
  • Eun-Soo Jung Chonbuk National University Hospital
  • Su-Jin Jung Chonbuk National University Hospital
  • Soo-Wan Chae Chonbuk National University Hospital
  • Byung-Hyun Park Chonbuk National University Medical School
Keywords: glucose uptake, muscle, steatosis, insulin, hypertriglyceridemia

Abstract

Background: Augmenting glucose utilization in skeletal muscle via the phosphatidylinositol-3 kinase (PI3
kinase)/protein kinase B (Akt) pathway or the adenosine monophosphate (AMP)-activated protein kinase
(AMPK) pathway is necessary to regulate hyperglycemia in patients with type 2 diabetes mellitus.

Objective: We investigated the effect of mulberry leaf extract (MLE) on glucose uptake in skeletal muscle cells
and explored its in vivo antidiabetic potential.

Design: Male db/db mice were treated with either MLE (50 mg/kg, 100 mg/kg, and 250 mg/kg) or metformin
(100 mg/kg) for 8 weeks.

Results: MLE treatment stimulated glucose uptake, driven by enhanced translocation of glucose transporter
4 to cell membranes in L6 myotubes. These effects of MLE were synergistic with those of insulin and were
abolished in the presence of PI3K inhibitor or AMPK inhibitor. In db/db mice, supplementation with MLE
decreased fasting blood glucose and insulin levels and enhanced insulin sensitivity, with increases of p-Akt
and p-AMPK in skeletal muscle. Moreover, MLE improved blood lipid parameters and attenuated hepatic
steatosis in diabetic db/db mice.

Discussion: These findings suggest that MLE exerts antidiabetic activity through stimulating glucose disposal
in skeletal muscle cells via the PI3K/Akt and AMPK pathways.

Conclusions: MLE can potentially improve hyperglycemia and hepatic steatosis in patients with type 2 diabetes.

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References


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Published
2018-08-22
How to Cite
1.
Bae U-J, Jung E-S, Jung S-J, Chae S-W, Park B-H. Mulberry leaf extract displays antidiabetic activity in <em>db/db</em> mice <em>via</em&gt; Akt and AMP-activated protein kinase phosphorylation. fnr [Internet]. 2018Aug.22 [cited 2018Nov.19];620. Available from: https://foodandnutritionresearch.net/index.php/fnr/article/view/1473
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Original Articles