Hydrogen peroxide responsive miR153 targets Nrf2/ARE cytoprotection in paraquat induced dopaminergic neurotoxicity

Abstract

Epidemiological and animal studies suggest that environmental toxins including paraquat (PQ) increase the risk of developing Parkinson's disease (PD) by damaging nigrostriatal dopaminergic neurons. We previously showed that overexpression of a group of microRNAs (miRs) affects the antioxidant promoting factor, Nrf2 and related glutathione-redox homeostasis in SH-SY5Y dopaminergic neurons. Although, dysregulation of redox balance by PQ is well documented, the role for miRs and their impact have not been elucidated. In the current study we investigated whether PQ impairs Nrf2 and its related cytoprotective machinery by misexpression of specific fine tune miRs in SH-SY5Y neurons. Real time PCR analysis revealed that PQ significantly (p<0.05) increased the expression of brain enriched miR153 with an associated decrease in Nrf2 and its function as revealed by decrease in 4× ARE activity and expression of GCLC and NQO1. Also, PQ and H2O2-induced decrease in Nrf2 3′ UTR activity was restored on miR153 site mutation suggesting a 3′ UTR interacting role. Overexpression of either anti-miR153 or Nrf2 cDNA devoid of 3′ UTR prevented PQ and H2O2-induced loss in Nrf2 activity confirming that PQ could cause miR153 to bind to and target Nrf2 3′ UTR thereby weakening the cellular antioxidant defense. Adenovirus mediated overexpression of cytoplasmic catalase (Ad cCAT) confirmed that PQ induced miR153 is hydrogen peroxide (H2O2) dependent. In addition, Ad cCAT significantly (p<0.05) negated the PQ induced dysregulation of Nrf2 and function along with minimizing ROS, caspase 3/7 activation and neuronal death. Altogether, these results suggest a critical role for oxidant mediated miR153-Nrf2/ARE pathway interaction in paraquat neurotoxicity. This novel finding facilitates the understanding of molecular mechanisms and to develop appropriate management alternatives to counteract PQ-induced neuronal pathogenesis.

Tanshinone IIA protects dopaminergic neurons against 6-hydroxydopamine-induced neurotoxicity through miR-153/NF-E2-related factor 2/antioxidant response element signaling pathway

“…Forced expression of miR-153 diminished GCLC and GSR expression, which resulted in alteration of Nrf2-dependent redox homeostasis (Narasimhan et al, 2012). Paraquat and H 2 O 2 have also been reported to significantly increase the expression of brain-enriched miR-153 with an associated decrease in Nrf2, ARE activity and expression of GCLC and NQO1 (Narasimhan et al, 2014). In our study, we found miR-153 was also significantly increased by 6-OHDA, and accounted for the reduction of Nrf2, which elicited a post-transcriptional repression of Nrf2 and its activity in dopaminergic SH-SY5Y neurons.…”

“…Once specific CDNA was generated, individual miRNA was detected using Tagman small RNA assay Real-time PCR analysis. Results were normalized to small nuclear RNA U6 and the data were expressed as Log 2-fold-change in respective miRs/U6 snRNA levels (Narasimhan et al, 2014).…”

Nrf2 Pathway in Age-Related Neurological Disorders: Insights into MicroRNAs

“…Interestingly, miR-153 has been found enriched in the brain, pointing out a pivotal role of this miR in the redox homeostasis of the brain. Moreover, the same group demonstrated that miR-153 was increased after exposure to paraquat (PQ), an herbicide that causes irreversible damages to DA neurons and therefore is considered to be a potent risk factor of developing PD [161]. The neurotoxicity of PQ is attributed to the ROS generation and consequent induction of oxidative stress.…”

“…Of interest, PQ significantly increases, through a mechanism H 2 O 2 -dependency, the expression of miR-153 in neuronal cells that, in turn, reduces both Nrf2 expression and activity. Conversely, the overexpression of an anti-miR-153 prevents ROS accumulation as H 2 O 2 -induced neuronal death [161]. Interestingly, both miR-7 and miR-153 are also implicated in the post-transcriptional regulation of α-Syn by binding specifically its 3'-UTR [158,162].…”

MicroRNA Pharmacoepigenetics: Posttranscriptional Regulation Mechanisms behind Variable Drug Disposition and Strategy to Develop More Effective Therapy

“…BCRP/ABCG2, another important efflux transporter in ADME and MDR, is also regulated by a number of miRNAs via direct or indirect mechanisms ( Table 2). The MDR of S1 colon carcinoma cell line is Zhao et al, 2008;Guttilla et al, 2012;Wei et al, 2014a Let-7 Reporter assay, mRNA/protein expression, and function study Zhao et al, 2011 miR-18a Reporter assay, protein expression, association and function study Liu et al, 2009 miR-18a/b, -19b, -20b, -193b, -206 Reporter assay, protein expression Castellano et al, 2009;Leivonen et al, 2009b miR-145 Reporter assay, mRNA and protein expression, and function study Spizzo et al, 2010 miR-22 Reporter assay, protein expression, and function study Pandey and Picard, 2009;Xiong et al, 2010 miR-206 Reporter assay, protein expression, and function study Adams et al, 2007;Kondo et al, 2008 miR-27a via zinc finger and BTB domain containing 10 (ZBTB10) Li et al, 2010a miR-219-5p Reporter assay, mRNA/protein expression, association and function Huang et al, 2015 miR-135b Reporter assay, mRNA and protein expression Aakula et al, 2015 NFE2L2/Nrf2 miR-144 Reporter assay, mRNA and protein expression, and function study Sangokoya et al, 2010 miR-28 Reporter assay, mRNA and protein expression Yang et al, 2011 miR-200a (Activation) via Kelch-like ECH-associated protein 1 (Keap1) Eades et al, 2011;Yang et al, 2014 miR-153, -27a, -142-5p, -144 Reporter assay, mRNA and protein expression, and function study Narasimhan et al, 2012Narasimhan et al, , 2014 Protein expression, and function study Singh et al, 2013 miR-507, -634, -450, -129-5p Reporter assay, mRNA and protein expression, and function study Yamamoto et al, 2014 miR-34a mRNA and protein expression Huang et al, 2014 miR-340 Reporter assay, mRNA and protein expression, and function study Shi et al, 2014a miR-141 via Kelch-like ECH-associated protein 1 (Keap1) …”