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MicroRNA expression in response to controlled exposure to diesel exhaust: attenuation by the antioxidant N-acetylcysteine in a randomized crossover study.

Yamamoto M, Singh A, Sava F, Pui M, Tebbutt SJ, Carlsten C - Environ. Health Perspect. (2013)

Bottom Line: Expression of miR-21, miR-30e, miR-215, and miR-144 was significantly associated with DEP.NRF2 and its downstream antioxidant genes [glutamate cysteine ligase catalytic subunit (GCLC) and NAD(P)H:quinone oxidoreductase 1 (NQO1)] were negatively associated with miR-144 levels.Oxidative stress appears to mediate DE-associated changes in miR-144.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Division of Respiratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.

ABSTRACT

Background: Adverse health effects associated with diesel exhaust (DE) are thought to be mediated in part by oxidative stress, but the detailed mechanisms are largely unknown. MicroRNAs (miRNAs) regulate gene expression post-transcriptionally and may respond to exposures such as DE.

Objectives: We profiled peripheral blood cellular miRNAs in participants with mild asthma who were exposed to controlled DE with and without antioxidant supplementation.

Methods: Thirteen participants with asthma underwent controlled inhalation of filtered air and DE in a double-blinded, randomized crossover study of three conditions: a) DE plus placebo (DEP), b) filtered air plus placebo (FAP), or c) DE with N-acetylcysteine supplementation (DEN). Total cellular RNA was extracted from blood drawn before exposure and 6 hr after exposure for miRNA profiling by the NanoString nCounter assay. MiRNAs significantly associated with DEP exposure and a predicted target [nuclear factor (erythroid-derived 2)-like 2 (NRF2)] as well as antioxidant enzyme genes were assessed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) for validation, and we also assessed the ability of N-acetylcysteine supplementation to block the effect of DE on these specific miRNAs. 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured in plasma as a systemic oxidative stress marker.

Results: Expression of miR-21, miR-30e, miR-215, and miR-144 was significantly associated with DEP. The change in miR-144 was validated by RT-qPCR. NRF2 and its downstream antioxidant genes [glutamate cysteine ligase catalytic subunit (GCLC) and NAD(P)H:quinone oxidoreductase 1 (NQO1)] were negatively associated with miR-144 levels. Increases in miR-144 and miR-21 were associated with plasma 8-hydroxydeoxyguanosine 8-OHdG level and were blunted by antioxidant (i.e, DEN).

Conclusions: Systemic miRNAs with plausible biological function are altered by acute moderate-dose DE exposure. Oxidative stress appears to mediate DE-associated changes in miR-144.

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Related in: MedlinePlus

Scatter plots of miR-144 compared with GCLC, NQO1, and NRF2. The plots show log2-transformed levels measured by RT-qPCR in post-FAP and post-DEP. The p-values refer to the association analyzed using limma.
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f2: Scatter plots of miR-144 compared with GCLC, NQO1, and NRF2. The plots show log2-transformed levels measured by RT-qPCR in post-FAP and post-DEP. The p-values refer to the association analyzed using limma.

Mentions: The association of NRF2 and antioxidant genes with miR-144. Among predicted target genes from a database of miRNAs (http://www.miRDB.org), we selected NRF2 as a candidate target gene for miR-144, whose role in oxidative stress pathways was previously demonstrated (Sangokoya et al. 2010). Given the purported role of miR-144 in target gene expression, expression of genes coding for NRF2 and enzymes NQO1 and GCLC, which are downstream of NRF2, were assessed and found negatively associated with miR-144 levels (p = 0.020, 0.001, < 0.0001, respectively, Figure 2).


MicroRNA expression in response to controlled exposure to diesel exhaust: attenuation by the antioxidant N-acetylcysteine in a randomized crossover study.

Yamamoto M, Singh A, Sava F, Pui M, Tebbutt SJ, Carlsten C - Environ. Health Perspect. (2013)

Scatter plots of miR-144 compared with GCLC, NQO1, and NRF2. The plots show log2-transformed levels measured by RT-qPCR in post-FAP and post-DEP. The p-values refer to the association analyzed using limma.
© Copyright Policy - public-domain
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3672916&req=5

f2: Scatter plots of miR-144 compared with GCLC, NQO1, and NRF2. The plots show log2-transformed levels measured by RT-qPCR in post-FAP and post-DEP. The p-values refer to the association analyzed using limma.
Mentions: The association of NRF2 and antioxidant genes with miR-144. Among predicted target genes from a database of miRNAs (http://www.miRDB.org), we selected NRF2 as a candidate target gene for miR-144, whose role in oxidative stress pathways was previously demonstrated (Sangokoya et al. 2010). Given the purported role of miR-144 in target gene expression, expression of genes coding for NRF2 and enzymes NQO1 and GCLC, which are downstream of NRF2, were assessed and found negatively associated with miR-144 levels (p = 0.020, 0.001, < 0.0001, respectively, Figure 2).

Bottom Line: Expression of miR-21, miR-30e, miR-215, and miR-144 was significantly associated with DEP.NRF2 and its downstream antioxidant genes [glutamate cysteine ligase catalytic subunit (GCLC) and NAD(P)H:quinone oxidoreductase 1 (NQO1)] were negatively associated with miR-144 levels.Oxidative stress appears to mediate DE-associated changes in miR-144.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine, Division of Respiratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.

ABSTRACT

Background: Adverse health effects associated with diesel exhaust (DE) are thought to be mediated in part by oxidative stress, but the detailed mechanisms are largely unknown. MicroRNAs (miRNAs) regulate gene expression post-transcriptionally and may respond to exposures such as DE.

Objectives: We profiled peripheral blood cellular miRNAs in participants with mild asthma who were exposed to controlled DE with and without antioxidant supplementation.

Methods: Thirteen participants with asthma underwent controlled inhalation of filtered air and DE in a double-blinded, randomized crossover study of three conditions: a) DE plus placebo (DEP), b) filtered air plus placebo (FAP), or c) DE with N-acetylcysteine supplementation (DEN). Total cellular RNA was extracted from blood drawn before exposure and 6 hr after exposure for miRNA profiling by the NanoString nCounter assay. MiRNAs significantly associated with DEP exposure and a predicted target [nuclear factor (erythroid-derived 2)-like 2 (NRF2)] as well as antioxidant enzyme genes were assessed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) for validation, and we also assessed the ability of N-acetylcysteine supplementation to block the effect of DE on these specific miRNAs. 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured in plasma as a systemic oxidative stress marker.

Results: Expression of miR-21, miR-30e, miR-215, and miR-144 was significantly associated with DEP. The change in miR-144 was validated by RT-qPCR. NRF2 and its downstream antioxidant genes [glutamate cysteine ligase catalytic subunit (GCLC) and NAD(P)H:quinone oxidoreductase 1 (NQO1)] were negatively associated with miR-144 levels. Increases in miR-144 and miR-21 were associated with plasma 8-hydroxydeoxyguanosine 8-OHdG level and were blunted by antioxidant (i.e, DEN).

Conclusions: Systemic miRNAs with plausible biological function are altered by acute moderate-dose DE exposure. Oxidative stress appears to mediate DE-associated changes in miR-144.

Show MeSH
Related in: MedlinePlus