Antidiabetic, antihyperlipidemic and antioxidant activities of a novel proteoglycan from ganoderma lucidum fruiting bodies on db/db mice and the possible mechanism

PLoS One. 2013 Jul 11;8(7):e68332. doi: 10.1371/journal.pone.0068332. Print 2013.

Abstract

Previously, we screened a proteoglycan for anti-hyperglycemic, named FYGL, from Ganoderma Lucidum. For further research of the antidiabetic mechanisms of FYGL in vivo, the glucose homeostasis, activities of insulin-sensitive enzymes, glucose transporter expression and pancreatic function were analyzed using db/db mice as diabetic models in the present work. FYGL not only lead to a reduction in glycated hemoglobin level, but also an increase in insulin and C-peptide level, whereas a decrease in glucagons level and showed a potential for the remediation of pancreatic islets. FYGL also increased the glucokinase activities, and simultaneously lowered the phosphoenol pyruvate carboxykinase activities, accompanied by a reduction in the expression of hepatic glucose transporter protein 2, while the expression of adipose and skeletal glucose transporter protein 4 was increased. Moreover, the antioxidant enzyme activities were also increased by FYGL treatment. Thus, FYGL was an effective antidiabetic agent by enhancing insulin secretion and decreasing hepatic glucose output along with increase of adipose and skeletal muscle glucose disposal in the late stage of diabetes. Furthermore, FYGL is beneficial against oxidative stress, thereby being helpful in preventing the diabetic complications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / metabolism*
  • Biological Factors / pharmacology*
  • Blood Glucose / drug effects
  • C-Peptide / blood
  • C-Peptide / metabolism
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetes Mellitus, Type 2 / metabolism
  • Disease Models, Animal
  • Glucokinase / metabolism
  • Glucose / metabolism
  • Glucose Transporter Type 2
  • Glucose Transporter Type 4
  • Glycated Hemoglobin A / metabolism
  • Hypoglycemic Agents / pharmacology*
  • Hypolipidemic Agents / pharmacology*
  • Insulin / blood
  • Insulin / metabolism
  • Insulin Resistance
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / metabolism
  • Liver / drug effects
  • Liver / enzymology
  • Liver / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism
  • Oxidative Stress / drug effects
  • Phosphoenolpyruvate Carboxykinase (ATP) / metabolism
  • Proteoglycans / pharmacology*
  • Reishi / metabolism*

Substances

  • Antioxidants
  • Biological Factors
  • Blood Glucose
  • C-Peptide
  • Glucose Transporter Type 2
  • Glucose Transporter Type 4
  • Glycated Hemoglobin A
  • Hypoglycemic Agents
  • Hypolipidemic Agents
  • Insulin
  • Proteoglycans
  • Glucokinase
  • Phosphoenolpyruvate Carboxykinase (ATP)
  • Glucose

Grant support

This work was supported by the Natural Science Foundation of China (20673022, 21074025), the Soft Science Program of Jing-An district in Shanghai (2008RZ002), Scientific Program of Shanghai Municipal Public Health Bureau (2008220, 2010231). Science and technology innovation program of Science and Technology Commission of Shanghai Municipality (STCSM) (11DZ1971802), Innovation Program of Shanghai Municipal Education Commission (12ZZ009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.