Activation of autophagic flux and the Nrf2/ARE signaling pathway by hydrogen sulfide protects against acrylonitrile-induced neurotoxicity in primary rat astrocytes
- 566 Downloads
Hydrogen sulfide (H2S), the third gasotransmitter, has been shown to act as a neuroprotective factor in numerous pathological processes; however, its underlying mechanism(s) of action remain unclear. It is widely accepted that activation of moderate autophagy and the Nrf2/ARE signaling pathway play important roles in the biological self-defense systems. In the present study, we investigated whether exogenous H2S protects against the cytotoxicity of acrylonitrile (AN), a neurotoxin, in primary rat astrocytes. We found that pretreatment for 1 h with sodium hydrosulfide (NaHS), a donor of H2S (200–800 µM), significantly attenuated the AN-induced decrease in cell viability, increase in lactate dehydrogenase release and morphological changes. Furthermore, NaHS significantly attenuated AN-induced oxidative stress by reducing reactive oxygen species (ROS) levels and increasing glutathione (GSH) concentration. Moreover, NaHS activated the autophagic flux, detectable as a change in autophagy-related proteins (Beclin-1, Atg5 and p62), the formation of acidic vesicular organelles and LC3B aggregation, confirmed by adenoviral expression of mRFP–GFP–LC3. Additionally, NaHS stimulated translocation of Nrf2 into the nucleus and increased expression of heme oxygenase-1 and γ-glutamylcysteine synthetase, downstream targets of Nrf2. Notably, the autophagy inhibitor 3-methyladenine and Beclin-1, or Nrf2-targeted siRNA, significantly attenuated the neuroprotective effects of NaHS against AN-induced neurotoxicity. In conclusion, we identified a crucial role of autophagy and the Nrf2/ARE signaling pathway in H2S-mediated neuroprotection against AN-induced toxicity in primary rat astrocytes. Our findings provide novel insights into the mechanisms of H2S-mediated neuroprotection, and suggest that H2S-based donors may serve as potential new candidate drugs to treat AN-induced neurotoxicity.
KeywordsHydrogen sulfide Acrylonitrile Astrocyte Autophagy Nrf2 Oxidative stress
This work was partly supported in part by the Natural Science Foundation of China (Nos. 30872139, 81273124, 81302459) and by grants from the National Institute of Environmental Health Sciences (NIEHS R01ES07331, NIEHS R01ES10563 and NIEHS R01ES020852). We thank Barry Patel, PhD, from Liwen Bianji, Edanz Group China (http://www.liwenbianji.cn/ac), for editing the English text of a draft of this manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that there is no conflict of interest regarding the publication of this paper.
- Decker T, Lohmannmatthes ML (1988) A quick and simple method for the quantitation of lactate dehydrogenase release in measurements of cellular cytotoxicity and tumor necrosis factor (TNF) activity. J Immunol Methods 115(1):61–69. https://doi.org/10.1016/0022-1759(88)90310-9 CrossRefPubMedGoogle Scholar
- He CH, Gong P, Fau - Hu B, Hu B, Fau-Stewart D et al (2001) Identification of activating transcription factor 4 (ATF4) as an Nrf2-interacting protein. Implication for heme oxygenase-1 gene regulation. J Biol Chem 276(24):20858–20865. https://doi.org/10.1074/jbc.M101198200 CrossRefPubMedGoogle Scholar
- He Y, Wang S, Xing G et al (2013) Acrylonitrile has distinct hormetic effects on acetyl-cholinesterase activity in mouse brain and blood that are modulated by ethanol. Dose-Response 11(1):49–59. https://doi.org/10.2203/dose-response.11-030.Yuanqing CrossRefGoogle Scholar
- Kamat PK, Kalani A, Tyagi SC, Tyagi N (2015) Hydrogen sulfide epigenetically attenuates homocysteine-induced mitochondrial toxicity mediated through NMDA receptor in mouse brain endothelial (bEnd3) cells. J Cell Physiol 230(2):378–394. https://doi.org/10.1002/jcp.24722 CrossRefPubMedPubMedCentralGoogle Scholar
- Kimura S, Noda T, Fau - Yoshimori T, Yoshimori T (2007) Dissection of the autophagosome maturation process by a novel reporter protein, tandem fluorescent-tagged LC3. Autophagy 3(5):452–460 https://doi.org/10.4161/auto.4451
- Koike S, Nishimoto S, Ogasawara Y (2017) Cysteine persulfides and polysulfides produced by exchange reactions with H(2)S protect SH-SY5Y cells from methylglyoxal-induced toxicity through Nrf2 activation. Redox Biol 12:530–539. https://doi.org/10.1016/j.redox.2017.03.020 CrossRefPubMedPubMedCentralGoogle Scholar
- Lu M, Hu LF, Hu G, Bian JS (2008) Hydrogen sulfide protects astrocytes against H(2)O(2)-induced neural injury via enhancing glutamate uptake. Free Radic Biol Med 45(12):1705–1713. https://doi.org/10.1016/j.freeradbiomed.2008.09.014 CrossRefPubMedGoogle Scholar
- Medeiros JV, Bezerra VHGomes AS (2009) Hydrogen sulfide prevents ethanol-induced gastric damage in mice: role of ATP-sensitive potassium channels and capsaicin-sensitive primary afferent neurons. J Pharmacol Exp Ther 330(3):764–770. https://doi.org/10.1124/jpet.109.152801 CrossRefPubMedGoogle Scholar
- Reiffenstein RJ, Hulbert WC, Roth SH (1992) Toxicity of hydrogen sulfide. Annu Rev Pharmacol 32(1):109–134. https://doi.org/10.1146/annurev.pa.32.040192.000545 CrossRefGoogle Scholar
- Scott A (2013) Acrylonitrile fumes kill one in Belgium. In: Business concentrates. http://cen.acs.org/articles/91/i19/Acrylonitrile-Fumes-Kill-One-Belgium.html?type=paidArticleContent Accessed 21 June 2017
- Specia M (2015) Thousands evacuated after train carrying toxic chemicals derails in Tennessee. In. http://mashable.com/2015/07/02/train-derailment-tennessee/#wdowKufr38qW Accessed 21 June 2017
- Yadav V, Gao XH, Willard B, Hatzoglou M, Banerjee R, Kabil O (2017) Hydrogen sulfide modulates eukaryotic translation initiation factor 2alpha (eIF2alpha) phosphorylation status in the integrated stress-response pathway. J Biol Chem 292(32):13143–13153. https://doi.org/10.1074/jbc.M117.778654 CrossRefPubMedPubMedCentralGoogle Scholar
- Yang H, Mao Y, Tan B, Luo S, Zhu Y (2015) The protective effects of endogenous hydrogen sulfide modulator, S-propargyl-cysteine, on high glucose-induced apoptosis in cardiomyocytes: A novel mechanism mediated by the activation of Nrf2. Eur J Pharmacol 761:135–143. https://doi.org/10.1016/j.ejphar.2015.05.001 CrossRefPubMedGoogle Scholar