Synthesis and Biological Evaluation of Novel Gigantol Derivatives as Potential Agents in Prevention of Diabetic Cataract

PLoS One. 2015 Oct 30;10(10):e0141092. doi: 10.1371/journal.pone.0141092. eCollection 2015.

Abstract

As a continuation of our efforts directed towards the development of natural anti-diabetic cataract agents, gigantol was isolated from Herba dendrobii and was found to inhibit both aldose reductase (AR) and inducible nitric oxide synthase (iNOS) activity, which play a significant role in the development and progression of diabetic cataracts. To improve its bioefficacy and facilitate use as a therapeutic agent, gigantol (compound 14f) and a series of novel analogs were designed and synthesized. Analogs were formulated to have different substituents on the phenyl ring (compounds 4, 5, 8, 14a-e), substitute the phenyl ring with a larger steric hindrance ring (compounds 10, 17c) or modify the carbon chain (compounds 17a, 17b, 21, 23, 25). All of the analogs were tested for their effect on AR and iNOS activities and on D-galactose-induced apoptosis in cultured human lens epithelial cells. Compounds 5, 10, 14a, 14b, 14d, 14e, 14f, 17b, 17c, 23, and 25 inhibited AR activity, with IC50 values ranging from 5.02 to 288.8 μM. Compounds 5, 10, 14b, and 14f inhibited iNOS activity with IC50 ranging from 432.6 to 1188.7 μM. Compounds 5, 8, 10, 14b, 14f, and 17c protected the cells from D-galactose induced apoptosis with viability ranging from 55.2 to 76.26%. Of gigantol and its analogs, compound 10 showed the greatest bioefficacy and is warranted to be developed as a therapeutic agent for diabetic cataracts.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aldehyde Reductase / antagonists & inhibitors
  • Apoptosis
  • Bibenzyls / chemical synthesis*
  • Bibenzyls / chemistry
  • Bibenzyls / pharmacology
  • Cataract / enzymology
  • Cataract / etiology
  • Cataract / prevention & control
  • Cell Survival / drug effects
  • Cells, Cultured
  • Diabetes Complications / enzymology
  • Diabetes Complications / prevention & control
  • Enzyme Inhibitors / chemical synthesis*
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Epithelial Cells / cytology
  • Epithelial Cells / drug effects*
  • Epithelial Cells / enzymology
  • Guaiacol / analogs & derivatives*
  • Guaiacol / chemical synthesis
  • Guaiacol / chemistry
  • Guaiacol / pharmacology
  • Humans
  • Hypoglycemic Agents / chemical synthesis*
  • Hypoglycemic Agents / chemistry
  • Hypoglycemic Agents / pharmacology
  • Lens, Crystalline / cytology
  • Lens, Crystalline / drug effects*
  • Molecular Structure
  • Nitric Oxide Synthase Type II / antagonists & inhibitors
  • Structure-Activity Relationship

Substances

  • Bibenzyls
  • Enzyme Inhibitors
  • Hypoglycemic Agents
  • gigantol
  • Guaiacol
  • Aldehyde Reductase
  • Nitric Oxide Synthase Type II

Grants and funding

This work was supported by the National Natural Science Foundation of China (81274157, 81102674), Guangzhou Science & Technology Planning Project (2014J4100082), Guangdong Natural Science Foundation (S2011010005661), Guangdong Science & Technology Planning Project (2011B031700076, 2009B090300335) and the U.S. Department of Agriculture (USDA)/Agricultural Research Service (Cooperative Agreement No. 1950-5100-087).