Graptopetalum paraguayense and resveratrol ameliorates carboxymethyllysine (CML)-induced pancreas dysfunction and hyperglycemia.

Abstract

Hyperglycemia is associated with advanced glycation end products (AGEs). Recently, AGEs were found to cause pancreatic damage, oxidative stress, and hyperglycemia through the AGE receptor. Carboxymethyllysine (CML) is an AGE but whether it induces pancreatic dysfunction remains unclear. Graptopetalum paraguayense, a vegetable consumed in Taiwan, has been used in folk medicine and is an antioxidant that protects against liver damage. We investigated the protective properties of G. paraguayense 95% ethanol extracts (GPEs) against CML-induced pancreatic damage. The results indicated that resveratrol, GPE, and gallic acid (the active compound of GPE) increased insulin synthesis via upregulation of pancreatic peroxisome proliferator activated-receptor-γ (PPARγ) and pancreatic-duodenal homeobox-1 (PDX-1) but inhibited the expression of CML-mediated CCAAT/enhancer binding protein-β (C/EBPβ), a negative regulator of insulin production. Moreover, resveratrol and GPE also strongly activated nuclear factor-erythroid 2-related factor 2 (Nrf2) to attenuate oxidative stress and improve insulin sensitivity in the liver and muscle of CML-injected C57BL/6 mice and resulted in reduced blood glucose levels. Taken together, these findings suggested that GPE and gallic acid could potentially be used as a food supplement to protect against pancreatic damage and the development of diabetes.

• Authors: Bao-Hong Lee, Chia-Chen Lee, Yu-Hsiang Cheng, Wen-Chang Chang, Wei-Hsuan Hsu, She-Ching Wu
• Journal: Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association (Food Chem Toxicol) Vol. 62 Pg. 492-8 (Dec 2013) ISSN: 1873-6351 [Electronic] England
• PMID: 24036142 (Publication Type: Journal Article)
• Copyright: Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical References

• Homeodomain Proteins
• Insulin
• NF-E2-Related Factor 2
• Nfe2l2 protein, mouse
• PPAR gamma
• Plant Extracts
• Stilbenes
• Trans-Activators
• pancreatic and duodenal homeobox 1 protein
• Gallic Acid
• N(6)-carboxymethyllysine
• Lysine
• Resveratrol

Topics

• Animals
• Crassulaceae (chemistry)
• Gallic Acid (analysis, pharmacology)
• Homeodomain Proteins (metabolism)
• Hyperglycemia (chemically induced, drug therapy, physiopathology)
• Insulin (blood)
• Liver (drug effects, metabolism)
• Lysine (analogs & derivatives, toxicity)
• Mice
• Mice, Inbred C57BL
• NF-E2-Related Factor 2 (metabolism)
• Oxidative Stress (drug effects)
• PPAR gamma (metabolism)
• Pancreas (drug effects, physiopathology)
• Plant Extracts (pharmacology)
• Resveratrol
• Stilbenes (pharmacology)
• Taiwan
• Trans-Activators (metabolism)