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


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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How to Cite
Bae, U.-J., Jung, E.-S., Jung, S.-J., Chae, S.-W., & Park, B.-H. (2018). Mulberry leaf extract displays antidiabetic activity in <em>db/db</em> mice <em>via</em&gt; Akt and AMP-activated protein kinase phosphorylation. Food & Nutrition Research, 62.
Original Articles