Induction of anti-aging gene klotho with a small chemical compound that demethylates CpG islands

Oncotarget. 2017 Jul 18;8(29):46745-46755. doi: 10.18632/oncotarget.18608.

Abstract

Klotho (KL) is described as an anti-aging gene because mutation of Kl gene leads to multiple pre-mature aging phenotypes and shortens lifespan in mice. Growing evidence suggests that an increase in KL expression may be beneficial for age-related diseases such as arteriosclerosis and diabetes. It remains largely unknown, however, how Kl expression could be induced. Here we discovered novel molecular mechanism for induction of Kl expression with a small molecule 'Compound H', N-(2-chlorophenyl)-1H-indole-3-caboxamide. Compound H was originally identified through a high-throughput screening of small molecules for identifying Kl inducers. However, how Compound H induces Kl expression has never been investigated. We found that Compound H increased Kl expression via demethylation in CpG islands of the Kl gene. The demethylation was accomplished by activating demethylases rather than inhibiting methylases. Due to demethylation, Compound H enhanced binding of transcription factors, Pax4 and Kid3, to the promoter of the Kl gene. Pax4 and Kid3 regulated Kl promoter activity positively and negatively, respectively. Thus, our results show that demethylation is an important molecular mechanism that mediates Compound H-induced Kl expression. Further investigation is warranted to determine whether Compound H demethylates the Kl gene in vivo and whether it can serve as a therapeutic agent for repressing or delaying the onset of age-related diseases.

Keywords: CpG island; Kid3; Pax4; klotho; methylation.

MeSH terms

  • Aging / genetics*
  • Animals
  • CpG Islands*
  • DNA Methylation / drug effects*
  • Gene Expression Regulation / drug effects*
  • Glucuronidase / genetics*
  • HEK293 Cells
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism
  • Humans
  • Klotho Proteins
  • Mice
  • Paired Box Transcription Factors / genetics
  • Paired Box Transcription Factors / metabolism
  • Promoter Regions, Genetic
  • Protein Binding
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • Homeodomain Proteins
  • PAX4 protein, human
  • Paired Box Transcription Factors
  • Repressor Proteins
  • Transcription Factors
  • ZNF354C protein, human
  • Glucuronidase
  • Klotho Proteins