Dataset Information

N(6)-isopentenyladenosine and analogs activate the NRF2-mediated antioxidant response.

ABSTRACT: N(6)-isopentenyladenosine (i(6)A), a naturally occurring modified nucleoside, inhibits the proliferation of human tumor cell lines in vitro, but its mechanism of action remains unclear. Treatment of MCF7 human breast adenocarcinoma cells with i(6)A or with three synthetic analogs (allyl(6)A, benzyl(6)A, and butyl(6)A) inhibited growth and altered gene expression. About 60% of the genes that were differentially expressed in response to i(6)A treatment were also modulated by the analogs, and pathway enrichment analysis identified the NRF2-mediated oxidative stress response as being significantly modulated by all four compounds. Luciferase reporter gene assays in transfected MCF7 cells confirmed that i(6)A activates the transcription factor NRF2. Assays for cellular production of reactive oxygen species indicated that i(6)A and analogs had antioxidant effects, reducing basal levels and inhibiting the H2O2- or 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced production in MCF7 or dHL-60 (HL-60 cells induced to differentiate along the neutrophilic lineage) cell lines, respectively. In vivo, topical application of i(6)A or benzyl(6)A to mouse ears prior to TPA stimulation lessened the inflammatory response and significantly reduced the number of infiltrating neutrophils. These results suggest that i(6)A and analogs trigger a cellular response against oxidative stress and open the possibility of i(6)A and benzyl(6)A being used as topical anti-inflammatory drugs.

SUBMITTER: Dassano A

PROVIDER: S-EPMC3969604 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Abnormally increased resorption contributes to bone degenerative diseases such as Paget's disease of bone (PDB) through unclear mechanisms. Recently, the optineurin (OPTN) gene has been implicated in PDB, and global OPTN knockout mice (Optn-/-) were shown to exhibit increased formation of osteoclasts (osteoclastogenesis). Growing evidence, including our own, has demonstrated that intracellular reactive oxygen species (ROS) stimulated by receptor activator of nuclear factor kappa-B ligand (RANKL) can act as signaling molecules to promote osteoclastogenesis. Here, we report that OPTN interacts with nuclear factor erythroid-derived factor 2-related factor 2 (NRF2), the master regulator of the antioxidant response, defining a pathway through which RANKL-induced ROS could be regulated for osteoclastogenesis. In this study, monocytes from Optn-/- and wild-type (Optn+/+) mice were utilized to differentiate into osteoclasts, and both qRT-PCR and tartrate-resistant acid phosphatase (TRAP) staining showed that the Optn-/- monocytes exhibited enhanced osteoclastogenesis compared to the Optn+/+ cells. CellROX® staining, qRT-PCR, and Western blotting indicated that OPTN deficiency reduced the basal expression of Nrf2, inhibited the expression of NRF2-responsive antioxidants, and increased basal and RANKL-induced intracellular ROS levels, leading to enhanced osteoclastogenesis. Coimmunoprecipitation (co-IP) showed direct interaction, and immunofluorescence staining showed perinuclear colocalization of the OPTN-NRF2 granular structures during differentiation. Finally, curcumin and the other NRF2 activators attenuated the hyperactive osteoclastogenesis induced by OPTN deficiency. Collectively, our findings reveal a novel OPTN-mediated mechanism for regulating the NRF2-mediated antioxidant response in osteoclasts and extend the therapeutic potential of OPTN in the aging process resulting from ROS-triggered oxidative stress, which is associated with PDB and many other degenerative diseases.

Dataset Information

N(6)-isopentenyladenosine and analogs activate the NRF2-mediated antioxidant response.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets