Skip to main content

Advertisement

SpringerLink
Log in

Boric Acid Activation of eIF2α and Nrf2 Is PERK Dependent: a Mechanism that Explains How Boron Prevents DNA Damage and Enhances Antioxidant Status

  • Published:
Biological Trace Element Research Aims and scope Submit manuscript

Abstract

Boron is abundant in vegetables, nuts, legumes, and fruit and intake is associated with reduced risk of cancer and DNA damage and increased antioxidant status. Blood boric acid (BA) levels are approximately 10 μM BA in men at the mean US boron intake. Treatment of DU-145 human prostate cancer cells with 10 μM BA stimulates phosphorylation of elongation initiation factor 2α (eIF2α) at Ser51 leading to activation of the eIF2α/ATF4 pathway which activates the DNA damage-inducible protein GADD34. In the present study, we used MEF WT and MEF PERK (±) cells to test the hypothesis that BA-activated eIF2α phosphorylation requires protein kinase RNA-like endoplasmic reticulum kinase (PERK) and activates Nrf2 and the antioxidant response element (ARE). BA (10 μM) increased phosphorylation of eIF2α Ser51 in MEF WT cells at 1 h, but not in MEF Perk −/− cells exposed for as long as 6 h. GCN2 kinase-dependent phosphorylation of eIF2α Ser51 was activated in MEF PERK −/− cells by amino acid starvation. Nrf2 phosphorylation is PERK dependent and when activated is translocated from the cytoplasm to the nucleus where it acts as a transcription factor for ARE. DU-145 cells were treated with 10 μM BA and Nrf2 measured by immunofluorescence. Cytoplasmic Nrf2 was translocated to the nucleus at 1.5–2 h in DU-145 and MEF WT cells, but not MEF PERK −/− cells. Real-time PCR was used to measure mRNA levels of three ARE genes (HMOX-1, NQO1, and GCLC). Treatment with 10 μM BA increased the mRNA levels of all three genes at 1–4 h in DU-145 cells and HMOX1 and GCLC in MEF WT cells. These results extend the known boric acid signaling pathway to ARE-regulated genes. The BA signaling pathway can be expressed using the schematic [BA + cADPR → cADPR-BA → [[ER]i Ca2+↓] → 3 pathways: PERK/eIF2αP → pathways ATF4 and Nrf2; and [[ER]i Ca2+↓] → ER stress → ATF6 pathway. This signaling pathway provides a framework that links many of the molecular changes that underpin the biological effects of boron intake.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

Abbreviations

eIF2α:

Elongation initiation factor 2α

ATF4:

Activating transcription factor 4

GCN2:

General control nonderepressible 2

PERK:

Protein kinase RNA-like endoplasmic reticulum kinase

HRI:

Heme-regulated inhibitor kinase

PKR kinase:

Protein kinase R

MEF:

Mouse embryo fibroblasts

Nrf2:

Nuclear factor (erythroid-derived 2)-like 2

HMOX-1:

Heme oxygenase (decycling) 1

NQO1:

NAD(P)H dehydrogenase quinone 1

GCLC:

Glutamate-cysteine ligase catalytic subunit

ATF6:

Activating transcription factor 6

ER:

Endoplasmic reticulum

References

  1. Cui Y, Winton MI, Zhang ZF, Rainey C, Marshall J, De Kernion JB, Eckhert CD (2004) Dietary boron intake and prostate cancer risk. Oncol Rep 11(4):887–892

    CAS  PubMed  Google Scholar 

  2. Barranco WT, Eckhert CD (2004) Boric acid inhibits human prostate cancer cell proliferation. Cancer Lett 216:21–29

    Article  CAS  Google Scholar 

  3. Barranco WT, Hudak PF, Eckhert CD (2007) Evaluation of ecological and in vitro effects of boron on prostate cancer risk (United States). Cancer Causes Control 18:71–77

    Article  Google Scholar 

  4. Barranco W, Hudak P, Eckhert CD (2007b) Erratum: Evaluation of ecological and in vitro effects of boron on prostate cancer risk. Cancer Causes Control 18:583–584. https://doi.org/10.1007/s10552-007-9023-7

    Article  Google Scholar 

  5. Kim D, Que Hee S, Norris A, Faull K, Eckhert C (2006) Boric acid inhibits ADP-ribosyl cyclase non-competitively. J Chromatogr A 1115:246–252

    Article  CAS  Google Scholar 

  6. Henderson K, Stella SL, Kobylewski S, Eckhert CD (2009) Receptor activated Ca2+ release is inhibited by boric acid in prostate cancer cells. PLosONE 4:e6009. https://doi.org/10.1371/journal.pone.0006009

    Article  CAS  Google Scholar 

  7. Palakurthi SS, Aktas H, Grubissich H, Mortensen RM, Halperin JA (2001) Anticancer effects of thiazolidinediones are independent of peroxisome proliferator-activated receptor gamma and mediated by inhibition of translation initiation. Cancer Res 61:6213–6218

    CAS  PubMed  Google Scholar 

  8. Aktas H, Fluckiger R, Acosta JA, Savage JM, Palakurthi SS (1998) Depletion of interacellular Ca2+ stores, phosphorylation of eIF2a, and sustained inhibition of translation initiation mediate the anticancer effects of clotrimazole. Proc Natl Acad Sci U S A 95:8280–8285

    Article  CAS  Google Scholar 

  9. Palakurthi SS, Fluckiger R, Aktas H, Changolkar AK, Shahsafaei A, Harneit S, Kilic E, Halperin JA (2000) Inhibition of translation initiation mediates the anticancer effect of the n-3 polyunsaturated fatty acid eicosapentaenoic acid. Cancer Res 60:2919–2925

    CAS  PubMed  Google Scholar 

  10. Palam LR, Baird TD, Wek RC (2011) Phosphorylation of eIf2 facilitates ribosomal bypass of an inhibitory upstream ORF to enhance CHOP translation. J Biol Chem 286:10939–10949. https://doi.org/10.1074/jbc.M110.216093

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Sonenberg N, Hinnebusch AG (2009) Regulation of translation initiation in eukaryotes: mechanisms and biological targets. Cell 136:731–745. https://doi.org/10.1016/j.cell.2009.01.042

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Dever TE, Dar AC, Sicheri F (2007) The eIF2α kinases. In: Matthews MB, Sonenberg N, Hershey JWB (eds) Translational control in biology and medicine, Cold Spring Harbor Monograph, vol 48. Cold Spring Harbor Laboratory Press, New York, pp 319–344. https://doi.org/10.1101/087969767.48.319

  13. Carpick BW, Graziano V, Schneider D, Maitra RK, Lee X, Williams BR (1997) Characterization of the solution complex between the interferon-induced, double-stranded RNA-activated protein kinase and HIV-I trans-activating region RNA. J Biol Chem 272(14):9510–9516

    Article  CAS  Google Scholar 

  14. Manche L, Green SR, Schmedt C, Mathews MB (1992) Interactions between double-stranded RNA regulators and the protein kinase DAI. Mol Cell Biol 12(11):5238–5248

    Article  CAS  Google Scholar 

  15. Sharp TV, Moonan F, Romashko A, Joshi B, Barber GN, Jagus R (1998) The vaccinia virus E3L gene product interacts with both the regulatory and the substrate binding regions of PKR: implications for PKR autoregulation. Virology 250(2):302–315. https://doi.org/10.1006/viro.1998.9365

    Article  CAS  PubMed  Google Scholar 

  16. Dong J, Qiu H, Garcia-Barrio M, Anderson J, Hinnebusch AG (2000) Uncharged tRNA activates GCN2 by displacing the protein kinase moiety from a bipartite tRNA-binding domain. Mol Cell 6(2):269–279

    Article  CAS  Google Scholar 

  17. Wek SA, Zhu S, Wek RC (1995) The histidyl-tRNA synthetase-related sequence in the eIF-2 alpha protein kinase GCN2 interacts with tRNA and is required for activation in response to starvation for different amino acids. Mol Cell Biol 15(8):4497–4506

    Article  CAS  Google Scholar 

  18. Yun BG, Matts JA, Matts RL (2005) Interdomain interactions regulate the activation of the heme-regulated eIF 2 alpha kinase. Biochim Biophys Acta 1725(2):174–181. https://doi.org/10.1016/j.bbagen.2005.07.011

    Article  CAS  PubMed  Google Scholar 

  19. Henderson K, Kobylewski S, Yamada K, Eckhert C (2016) Boric acid induces cytoplasmic stress granule formation, eIF2-alpha phosphorylation, and ATF4 in prostate DU-145 cells. Biometals 28:133–141

    Article  Google Scholar 

  20. Cullinan SB, Zhang D, Hannink M, Arvisais E, Kaufman RJ, Diehl JA (2003) Nrf2 is a direct PERK substrate and effector of PERK-dependent cell survival. Mol Cell Biol 23(20):7198–7209

    Article  CAS  Google Scholar 

  21. Cullinan SB, Diehl JA (2006) Coordination of ER and oxidative stress signaling: the PERK/Nrf2 signaling pathway. Int J Biochem Cell Biol 38(3):317–332. https://doi.org/10.1016/j.biocel.2005.09.018

    Article  CAS  PubMed  Google Scholar 

  22. Bennett A, Rowe RI, Soch N, Eckhert CD (1999) Boron stimulates yeast (Saccharomyces cerevisiae) growth. J Nutr 129(12):2236–2238

    Article  CAS  Google Scholar 

  23. Zhang P, McGrath BC, Reinert J, Olsen DS, Lei L, Gill S, Wek SA, Vattem KM, Wek RC, Kimball SR, Jefferson LS, Cavener DR (2002) The GCN2 eIF2alpha kinase is required for adaptation to amino acid deprivation in mice. Mol Cell Biol 22(19):6681–6688

    Article  CAS  Google Scholar 

  24. Kang MI, Kobayashi A, Wakabayashi N, Kim SG, Yamamoto M (2004) Scaffolding of Keap1 to the actin cytoskeleton controls the function of Nrf2 as key regulator of cytoprotective phase 2 genes. Proc Natl Acad Sci USA 101(7):2046–2051. https://doi.org/10.1073/pnas.0308347100

    Article  CAS  PubMed  Google Scholar 

  25. Kensler TW, Wakabayashi N, Biswal S (2007) Cell survival responses to environmental stresses via the Keap1-Nrf2-ARE pathway. Ann Rev Pharm Toxicol 47:89–116. https://doi.org/10.1146/annurev.pharmtox.46.120604.141046

    Article  CAS  PubMed  Google Scholar 

  26. Nguyen T, Yang CS, Pickett CB (2004) The pathways and molecular mechanisms regulating Nrf2 activation in response to chemical stress. Free Radic Biol Med 37(4):433–441. https://doi.org/10.1016/j.freeradbiomed.2004.04.033

    Article  CAS  PubMed  Google Scholar 

  27. Itoh K, Chiba T, Takahashi S, Ishii T, Igarashi K, Katoh Y, Oyake T, Hayashi N, Satoh K, Hatayama I, Yamamoto M, Nabeshima Y (1997) An Nrf2/small Maf heterodimer mediates the induction of phase II detoxifying enzyme genes through antioxidant response elements. Biochem Biophys Res Commun 236(2):313–322

    Article  CAS  Google Scholar 

  28. Ma K, Vattem KM, Wek RC (2002) Dimerization and release of molecular chaperone inhibition facilitate activation of eukaryotic initiation factor-2 kinase in response to endoplasmic reticulum stress. J Biol Chem 277(21):18728–18735. https://doi.org/10.1074/jbc.M200903200

    Article  CAS  PubMed  Google Scholar 

  29. Credle JJ, Finer-Moore JS, Papa FR, Stroud RM, Walter P (2005) On the mechanism of sensing unfolded protein in the endoplasmic reticulum. Proc Natl Acad Sci U S A 102(52):18773–18784. https://doi.org/10.1073/pnas.0509487102

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Kobylewski SE, Henderson KA, Yamada KE, Eckhert CD (2016) Activation of the eIF2α/ATF4 and ATF6 pathways in DU-145 cells by boric acid at the concentration reported in men at the US mean boron intake. Biol Trace Elem Res 176:278–293. https://doi.org/10.1007/s12011-016-0824-y

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Eckhert CD, Yamada K (2014) Boric acid activates PERK and ARE at physiological levels. FASEB J 28(1 supplement):372.372

    Google Scholar 

  32. Khaliq H, Jing W, Ke X, Ke-Li Y, Peng-Peng S, Cui L, Wei-Wei Q, Zhixin L, Hua-Zhen L, Hui S, Ju-Ming Z, KeMei P (2018) Boron affects the development of the kidney through modulation of apoptosis, antioxidant capacity, and Nrf2 pathway in the African ostrich chicks. Biol Trace Elem Res. https://doi.org/10.1007/s12011-018-1280-7

  33. Turkez H (2008) Effects of boric acid and borax on titanium dioxide genotoxicity. J Appl Toxicol 28:658–664. https://doi.org/10.1002/jat.1318

    Article  CAS  PubMed  Google Scholar 

  34. Turkez H, Tata A, Hacimuftuoglu A, Ozdemir E (2010) Boric acid as a protector against paclitaxel genotoxicity. ACTA Biochim Pol 57:95–97

    Article  CAS  Google Scholar 

  35. Turkez H, Geyikoglu F, Tatar A, Keles MS, Kaplan L (2012) The effects of some boron compounds against heavy metal toxicity in human blood. Exp Toxicol Pathol 64:93–101

    Article  CAS  Google Scholar 

  36. Turkez H, Geyikoglu F, Dirican E, Tatar A (2012) In vitro studies on chemoprotective effect of borax against aflatoxin B1-induced genetic damage in human lymphocytes. Cytotechnology 64:607–612

    Article  CAS  Google Scholar 

  37. Ince S, Kucukkurt I, Demirel HH, Acaroz DA, Akbel E, Cigerci IH (2014) Protective effects of boron on cyclophosphamide induced lipid peroxidation and genotoxicity in rats. Chemosphere 108:197–204

    Article  CAS  Google Scholar 

  38. Yilma S, Ustundag A, Ulker OC, Duydu Y (2016) Protective effect of boric acid on oxidative DNA damage in Chinese hamster lung fibroblast V79 cell lines. Cell J 17:748–754

    Google Scholar 

  39. Sarikaya R, Erciyas K, Kara MI, Sezer U, Erciyas AF, Ay S (2016) Evaluation of genotoxic and antigenotoxic effects of boron by the somatic mutation and recombination test (SMART) on drosophila. Drug Chem Toxicol 39:400–406. https://doi.org/10.3109/01480545.2015.1130719

    Article  CAS  PubMed  Google Scholar 

  40. Tepedelen BE, Soya E, Korkma M (2016) Boric acid reduces the formation of DNA double strand breaks and accelerates wound healing process. Biol Trace Elem Res 174:309–318. https://doi.org/10.1007/s12011-016-0729-9

    Article  CAS  PubMed  Google Scholar 

  41. Alak G, Parlak V, Aslan ME, Ucar A, Atamanalp M, Turkez H (2018) Borax supplementation alleviates hematotoxicity and DNA damage in rainbow trout (Oncorhynchus mykiss) exposed to copper. Biol Trace Elem Res. https://doi.org/10.1007/s12011-018-1399-6

  42. Hayashi A, Suzuki H, Itoh K, Yamamoto M, Sugiyama Y (2003) Transcription factor Nrf2 is required for the constitutive and inducible expression of multidrug resistance-associated protein 1 in mouse embryo fibroblasts. Biochem Biophys Res Commun 310(3):824–829

    Article  CAS  Google Scholar 

  43. Sasaki H, Sato H, Kuriyama-Matsumura K, Sato K, Maebara K, Wang H, Tamba M, Itoh K, Yamamoto M, Bannai S (2002) Electrophile response element-mediated induction of the cystine/glutamate exchange transporter gene expression. J Biol Chem 277(47):44765–44771. https://doi.org/10.1074/jbc.M208704200

    Article  CAS  PubMed  Google Scholar 

  44. Nguyen T, Sherratt PJ, Pickett CB (2003) Regulatory mechanisms controlling gene expression mediated by the antioxidant response element. Ann Rev Pharm Toxicol 43:233–260. https://doi.org/10.1146/annurev.pharmtox.43.100901.140229

    Article  CAS  PubMed  Google Scholar 

  45. Nguyen T, Huang HC, Pickett CB (2000) Transcriptional regulation of the antioxidant response element. Activation by Nrf2 and repression by MafK. J Biol Chem 275(20):15466–15473. https://doi.org/10.1074/jbc.M000361200

    Article  CAS  PubMed  Google Scholar 

  46. Venugopal R, Jaiswal AK (1996) Nrf1 and Nrf2 positively and c-Fos and Fra1 negatively regulate the human antioxidant response element-mediated expression of NAD(P)H:quinone oxidoreductase1 gene. Proc Natl Acad Sci U S A 93(25):14960–14965

    Article  CAS  Google Scholar 

  47. Wild AC, Moinova HR, Mulcahy RT (1999) Regulation of gamma-glutamylcysteine synthetase subunit gene expression by the transcription factor Nrf2. J Biol Chem 274(47):33627–33636

    Article  CAS  Google Scholar 

  48. Griffith OW, Mulcahy RT (2006) The enzymes of glutathione synthesis: γ-glutamylcysteine synthetase. In: Advances in enzymology and related areas of molecular biology: mechanism of enzyme action, Part A, vol 73. Wiley, Hoboken. https://doi.org/10.1002/9780470123195.ch7

    Chapter  Google Scholar 

  49. Wise CD, Drabkin DL (1964) Degradation of hemoglobin+ hemin to biliverdin by new cell-free enzyme system obtained from hemophagous organ of dog placenta. Fed Proc 23(2P1):223

    Google Scholar 

  50. Tenhunen R, Marver HS, Schmid R (1968) The enzymatic conversion of heme to bilirubin by microsomal heme oxygenase. Proc Natl Acad Sci U S A 61(2):748–755

    Article  CAS  Google Scholar 

  51. Jin X, Xu Z, Fan R, Wang C, Ji W, Ma Y, Cai W, Zhang Y, Yang N, Zou S, Zhou X, Li Y (2017) HO-1 alleviates cholesterol-induced oxidative stress through activation of Nrf2/ERK and inhibition of PI3K/AKT pathways in endothelial cells. Mol Med Rep 16:3519–3527. https://doi.org/10.3892/mmr.2017.6962

    Article  CAS  PubMed  Google Scholar 

  52. Colucci MA, Moody CJ, Couch GD (2008) Natural and synthetic quinones and their reduction by the quinone reductase enzyme NQO1: from synthetic organic chemistry to compounds with anticancer potential. Organ Biomol Chem 6(4):637–656. https://doi.org/10.1039/b715270a

    Article  CAS  Google Scholar 

  53. Alam J, Camhi S, Choi AM (1995) Identification of a second region upstream of the mouse heme oxygenase-1 gene that functions as a basal level and inducer-dependent transcription enhancer. J Biol Chem 270(20):11977–11984

    Article  CAS  Google Scholar 

  54. Camhi SL, Alam J, Otterbein L, Sylvester SL, Choi AM (1995) Induction of heme oxygenase-1 gene expression by lipopolysaccharide is mediated by AP-1 activation. Am J Respir Cell Mol Biol 13(4):387–398. https://doi.org/10.1165/ajrcmb.13.4.7546768

    Article  CAS  PubMed  Google Scholar 

  55. Morse D, Choi AM (2002) Heme oxygenase-1: the “emerging molecule” has arrived. Am J Respir Cell Mol Biol 27(1):8–16. https://doi.org/10.1165/ajrcmb.27.1.4862

    Article  CAS  PubMed  Google Scholar 

  56. Dinkova-Kostova AT, Talalay P (2010) NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1), a multifunctional antioxidant enzyme and exceptionally versatile cytoprotector. Arch Biochem Biophys 501(1):116–123. https://doi.org/10.1016/j.abb.2010.03.019

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  57. Barranco WT, Eckhert CD (2004) Boric acid inhibits human prostate cancer cell proliferation. Cancer Lett 216(1):21–29. https://doi.org/10.1016/j.canlet.2004.06.001

    Article  CAS  PubMed  Google Scholar 

  58. Kobylewski S, Henderson KA, Yamada K, Eckhert CD (2016) Activation of the EIF2a/ATF4 and ATF6 pathways in DU-45 cells by boric acid at the concentration reported in men at the US mean intake. Biol Trace Elem Res 176:278–293. https://doi.org/10.1007/s12011-016-0823-y

    Article  PubMed  PubMed Central  Google Scholar 

  59. Mengesdorf T, Althausen S, Oberndorfer I, Paschen W (2001) Response of neurons to an irreversible inhibition of endoplasmic reticulum Ca(2+)-ATPase: relationship between global protein synthesis and expression and translation of individual genes. Biochem J 356(Pt 3):805–812

    Article  CAS  Google Scholar 

  60. Jiang S, Chow SC, Nicotera P, Orrenius S (1994) Intracellular Ca2+ signals activate apoptosis in thymocytes: studies using the Ca(2+)-ATPase inhibitor thapsigargin. Exp Cell Res 212(1):84–92. https://doi.org/10.1006/excr.1994.1121

    Article  CAS  PubMed  Google Scholar 

  61. McCullough KD, Martindale JL, Klotz LO, Aw TY, Holbrook NJ (2001) Gadd153 sensitizes cells to endoplasmic reticulum stress by down-regulating Bcl2 and perturbing the cellular redox state. Mol Cell Biol 21(4):1249–1259. https://doi.org/10.1128/mcb.21.4.1249-1259.2001

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  62. Oyadomari S, Mori M (2004) Roles of CHOP/GADD153 in endoplasmic reticulum stress. Cell Death Differ 11(4):381–389. https://doi.org/10.1038/sj.cdd.4401373

    Article  CAS  Google Scholar 

  63. Cullinan SB, Diehl JA (2004) PERK-dependent activation of Nrf2 contributes to redox homeostasis and cell survival following endoplasmic reticulum stress. J Biol Chem 279(19):20108–20117. https://doi.org/10.1074/jbc.M314219200

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Interdepartmental Program in Molecular Toxicology, University of California, Los Angeles, 90095, CA, USA

    Kristin E. Yamada & Curtis D. Eckhert

  2. Department of Environmental Health Sciences, Fielding School of Public Health, University of California, 650 Charles E. Young Dr., Los Angeles, CA, 90095, USA

    Curtis D. Eckhert

Authors
  1. Kristin E. Yamada
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Curtis D. Eckhert
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Curtis D. Eckhert.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Yamada, K.E., Eckhert, C.D. Boric Acid Activation of eIF2α and Nrf2 Is PERK Dependent: a Mechanism that Explains How Boron Prevents DNA Damage and Enhances Antioxidant Status. Biol Trace Elem Res 188, 2–10 (2019). https://doi.org/10.1007/s12011-018-1498-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12011-018-1498-4

Keywords

Search

Navigation