Send to

Choose Destination
Antioxid Redox Signal. 2015 Nov 10;23(14):1092-105. doi: 10.1089/ars.2014.6025. Epub 2015 Jan 9.

Targeting of Gamma-Glutamyl-Cysteine Ligase by miR-433 Reduces Glutathione Biosynthesis and Promotes TGF-β-Dependent Fibrogenesis.

Author information

1 Departamento de Biología Celular e Inmunología, Centro de Biología Molecular "Severo Ochoa, " Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid , Madrid, Spain .
2 Cellular Biology in Renal Diseases Laboratory, Universidad Autonoma de Madrid , Madrid, Spain .
3 Department of Metabolomics, CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (Ciberehd) , Bizkaia, Spain .
4 Vascular Biology and Therapeutics Program, Department of Comparative Medicine, Yale University School of Medicine , New Haven, Connecticut.



Glutathione (GSH) is the main antioxidant against cell damage. Several pathological states course with reduced nucleophilic tone and perturbation of redox homeostasis due to changes in the 2GSH/GSSG ratio. Here, we investigated the regulation of the rate-limiting GSH biosynthetic heterodimeric enzyme γ-glutamyl-cysteine ligase (GCL) by microRNAs (miRNAs).


"In silico" analysis of the 3'- untranslated regions (UTRs) of both catalytic (GCLc) and regulatory (GCLm) subunits of GCL enabled an identification of miR-433 as a strong candidate for the targeting of GCL. Transitory overexpression of miR-433 in human umbilical vein endothelial cells (HUVEC) showed a downregulation of both GCLc and GCLm in a nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-independent manner. Increases in pro-oxidant stimuli such as exposure to hydrogen peroxide or GSH depletion in endothelial and hepatic cells caused an expected increase in GCLc and GCLm protein expression and abrogation of miR-433 levels, thus supporting a cross-regulation of these pathways. Treatment of HUVEC with miR-433 resulted in reduced antioxidant and redox potentials, increased S-glutathionylation, and reduced endothelial nitric oxide synthase activation. In vivo models of renal and hepatic fibrosis were associated with transforming growth factor β1 (TGF-β1)-related reduction of GCLc and GCLm levels that were miR-433 dependent.


We describe for the first time an miRNA, miR-433, capable of directly targeting GCL and promoting functional consequences in endothelial physiology and fibrotic processes by decreasing GSH levels.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Atypon Icon for PubMed Central
Loading ...
Support Center