Induction of quinone oxidoreductase 1 enzyme by Rhazya stricta through Nrf2-dependent mechanism

Mohamed A M El Gendy, Badreldin H. Ali, Karim Michail, Arno G. Siraki, Ayman O S El-Kadi

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Ethnopharmacological relevance: Rhazya stricta Decne. (Apocynaceae) is a common medicinal plant in the Arabian Peninsula, Pakistan and India. Rhazya stricta has been used traditionally to treat several diseases including tumors; however, the underlying mechanism is still not fully elucidated. Aim of the study: The aim of this study is to examine the ability of Rhazya stricta to induce a key enzyme involved in cancer chemoprevention, NAD(P)H:quinone oxidoreductase 1 (Nqo1) in murine and human hepatoma cells. Nqo1 is regulated by the nuclear factor erythroid 2-related factor 2 (Nrf2) and the aryl hydrocarbon receptor (AhR) transcription factors. Materials and methods: Rhazya stricta leaves were extracted using ethanol, the strong basic alkaloid fraction (AF) was isolated according to a bioassay-guided fractionation and its mass spectrum was used as a fingerprint for its identity. The effect of increasing concentrations of AF on Nqo1 was tested in murine hepatoma Hepa 1c1c7 and human HepG2 cells. The role of Nrf2-dependent mechanism was tested by using Nrf2-dependent luciferase assay and by determining the Nrf2 nuclear accumulation in Hepa 1c1c7 cells. The role of AhR-dependent mechanism was assessed by using an AhR-deficient version of murine hepatoma c12 cells. Results: AF significantly induced the Nqo1 at mRNA, protein and catalytic activity levels in murine hepatoma Hepa 1c1c7 cells. Moreover, the induction of Nqo1 by AF was completely abolished by using the transcriptional inhibitor, actinomycin D, implying a role of transcriptional regulation. In addition, the role of Nrf2 signaling pathway was confirmed by the induction of Nrf2-dependent luciferase activity and the induced Nrf2 nuclear accumulation in Hepa 1c1c7 cells. Interestingly, AF induced Nqo1 at mRNA and catalytic activity in c12 and HepG2 cells. Finally, the AF induced the Nrf2-dependent luciferase activity in HepG2 cells, confirming the role of Nrf2 in its regulation. Conclusions: The present study presents the first evidence that Rhazya stricta and its active strongly basic alkaloid fraction induce the chemopreventative enzyme, Nqo1 through Nrf2-dependent mechanism.

Original languageEnglish
Pages (from-to)416-424
Number of pages9
JournalJournal of Ethnopharmacology
Volume144
Issue number2
DOIs
Publication statusPublished - Nov 21 2012

Fingerprint

Apocynaceae
Alkaloids
Oxidoreductases
Aryl Hydrocarbon Receptors
Enzymes
Hepatocellular Carcinoma
Hep G2 Cells
Luciferases
Messenger RNA
Pakistan
Chemoprevention
Dermatoglyphics
Dactinomycin
Medicinal Plants
benzoquinone
Biological Assay
NAD
India
Neoplasms
Ethanol

Keywords

  • Chemoprevention
  • Nqo1
  • Nuclear factor erythroid 2-related factor 2
  • Rhazya stricta

ASJC Scopus subject areas

  • Pharmacology
  • Drug Discovery

Cite this

Induction of quinone oxidoreductase 1 enzyme by Rhazya stricta through Nrf2-dependent mechanism. / El Gendy, Mohamed A M; Ali, Badreldin H.; Michail, Karim; Siraki, Arno G.; El-Kadi, Ayman O S.

In: Journal of Ethnopharmacology, Vol. 144, No. 2, 21.11.2012, p. 416-424.

Research output: Contribution to journalArticle

El Gendy, Mohamed A M ; Ali, Badreldin H. ; Michail, Karim ; Siraki, Arno G. ; El-Kadi, Ayman O S. / Induction of quinone oxidoreductase 1 enzyme by Rhazya stricta through Nrf2-dependent mechanism. In: Journal of Ethnopharmacology. 2012 ; Vol. 144, No. 2. pp. 416-424.
@article{9e1f22a972e547c789ccc01d3a8f41c3,
title = "Induction of quinone oxidoreductase 1 enzyme by Rhazya stricta through Nrf2-dependent mechanism",
abstract = "Ethnopharmacological relevance: Rhazya stricta Decne. (Apocynaceae) is a common medicinal plant in the Arabian Peninsula, Pakistan and India. Rhazya stricta has been used traditionally to treat several diseases including tumors; however, the underlying mechanism is still not fully elucidated. Aim of the study: The aim of this study is to examine the ability of Rhazya stricta to induce a key enzyme involved in cancer chemoprevention, NAD(P)H:quinone oxidoreductase 1 (Nqo1) in murine and human hepatoma cells. Nqo1 is regulated by the nuclear factor erythroid 2-related factor 2 (Nrf2) and the aryl hydrocarbon receptor (AhR) transcription factors. Materials and methods: Rhazya stricta leaves were extracted using ethanol, the strong basic alkaloid fraction (AF) was isolated according to a bioassay-guided fractionation and its mass spectrum was used as a fingerprint for its identity. The effect of increasing concentrations of AF on Nqo1 was tested in murine hepatoma Hepa 1c1c7 and human HepG2 cells. The role of Nrf2-dependent mechanism was tested by using Nrf2-dependent luciferase assay and by determining the Nrf2 nuclear accumulation in Hepa 1c1c7 cells. The role of AhR-dependent mechanism was assessed by using an AhR-deficient version of murine hepatoma c12 cells. Results: AF significantly induced the Nqo1 at mRNA, protein and catalytic activity levels in murine hepatoma Hepa 1c1c7 cells. Moreover, the induction of Nqo1 by AF was completely abolished by using the transcriptional inhibitor, actinomycin D, implying a role of transcriptional regulation. In addition, the role of Nrf2 signaling pathway was confirmed by the induction of Nrf2-dependent luciferase activity and the induced Nrf2 nuclear accumulation in Hepa 1c1c7 cells. Interestingly, AF induced Nqo1 at mRNA and catalytic activity in c12 and HepG2 cells. Finally, the AF induced the Nrf2-dependent luciferase activity in HepG2 cells, confirming the role of Nrf2 in its regulation. Conclusions: The present study presents the first evidence that Rhazya stricta and its active strongly basic alkaloid fraction induce the chemopreventative enzyme, Nqo1 through Nrf2-dependent mechanism.",
keywords = "Chemoprevention, Nqo1, Nuclear factor erythroid 2-related factor 2, Rhazya stricta",
author = "{El Gendy}, {Mohamed A M} and Ali, {Badreldin H.} and Karim Michail and Siraki, {Arno G.} and El-Kadi, {Ayman O S}",
year = "2012",
month = "11",
day = "21",
doi = "10.1016/j.jep.2012.09.032",
language = "English",
volume = "144",
pages = "416--424",
journal = "Journal of Ethnopharmacology",
issn = "0378-8741",
publisher = "Elsevier Ireland Ltd",
number = "2",

}

TY - JOUR

T1 - Induction of quinone oxidoreductase 1 enzyme by Rhazya stricta through Nrf2-dependent mechanism

AU - El Gendy, Mohamed A M

AU - Ali, Badreldin H.

AU - Michail, Karim

AU - Siraki, Arno G.

AU - El-Kadi, Ayman O S

PY - 2012/11/21

Y1 - 2012/11/21

N2 - Ethnopharmacological relevance: Rhazya stricta Decne. (Apocynaceae) is a common medicinal plant in the Arabian Peninsula, Pakistan and India. Rhazya stricta has been used traditionally to treat several diseases including tumors; however, the underlying mechanism is still not fully elucidated. Aim of the study: The aim of this study is to examine the ability of Rhazya stricta to induce a key enzyme involved in cancer chemoprevention, NAD(P)H:quinone oxidoreductase 1 (Nqo1) in murine and human hepatoma cells. Nqo1 is regulated by the nuclear factor erythroid 2-related factor 2 (Nrf2) and the aryl hydrocarbon receptor (AhR) transcription factors. Materials and methods: Rhazya stricta leaves were extracted using ethanol, the strong basic alkaloid fraction (AF) was isolated according to a bioassay-guided fractionation and its mass spectrum was used as a fingerprint for its identity. The effect of increasing concentrations of AF on Nqo1 was tested in murine hepatoma Hepa 1c1c7 and human HepG2 cells. The role of Nrf2-dependent mechanism was tested by using Nrf2-dependent luciferase assay and by determining the Nrf2 nuclear accumulation in Hepa 1c1c7 cells. The role of AhR-dependent mechanism was assessed by using an AhR-deficient version of murine hepatoma c12 cells. Results: AF significantly induced the Nqo1 at mRNA, protein and catalytic activity levels in murine hepatoma Hepa 1c1c7 cells. Moreover, the induction of Nqo1 by AF was completely abolished by using the transcriptional inhibitor, actinomycin D, implying a role of transcriptional regulation. In addition, the role of Nrf2 signaling pathway was confirmed by the induction of Nrf2-dependent luciferase activity and the induced Nrf2 nuclear accumulation in Hepa 1c1c7 cells. Interestingly, AF induced Nqo1 at mRNA and catalytic activity in c12 and HepG2 cells. Finally, the AF induced the Nrf2-dependent luciferase activity in HepG2 cells, confirming the role of Nrf2 in its regulation. Conclusions: The present study presents the first evidence that Rhazya stricta and its active strongly basic alkaloid fraction induce the chemopreventative enzyme, Nqo1 through Nrf2-dependent mechanism.

AB - Ethnopharmacological relevance: Rhazya stricta Decne. (Apocynaceae) is a common medicinal plant in the Arabian Peninsula, Pakistan and India. Rhazya stricta has been used traditionally to treat several diseases including tumors; however, the underlying mechanism is still not fully elucidated. Aim of the study: The aim of this study is to examine the ability of Rhazya stricta to induce a key enzyme involved in cancer chemoprevention, NAD(P)H:quinone oxidoreductase 1 (Nqo1) in murine and human hepatoma cells. Nqo1 is regulated by the nuclear factor erythroid 2-related factor 2 (Nrf2) and the aryl hydrocarbon receptor (AhR) transcription factors. Materials and methods: Rhazya stricta leaves were extracted using ethanol, the strong basic alkaloid fraction (AF) was isolated according to a bioassay-guided fractionation and its mass spectrum was used as a fingerprint for its identity. The effect of increasing concentrations of AF on Nqo1 was tested in murine hepatoma Hepa 1c1c7 and human HepG2 cells. The role of Nrf2-dependent mechanism was tested by using Nrf2-dependent luciferase assay and by determining the Nrf2 nuclear accumulation in Hepa 1c1c7 cells. The role of AhR-dependent mechanism was assessed by using an AhR-deficient version of murine hepatoma c12 cells. Results: AF significantly induced the Nqo1 at mRNA, protein and catalytic activity levels in murine hepatoma Hepa 1c1c7 cells. Moreover, the induction of Nqo1 by AF was completely abolished by using the transcriptional inhibitor, actinomycin D, implying a role of transcriptional regulation. In addition, the role of Nrf2 signaling pathway was confirmed by the induction of Nrf2-dependent luciferase activity and the induced Nrf2 nuclear accumulation in Hepa 1c1c7 cells. Interestingly, AF induced Nqo1 at mRNA and catalytic activity in c12 and HepG2 cells. Finally, the AF induced the Nrf2-dependent luciferase activity in HepG2 cells, confirming the role of Nrf2 in its regulation. Conclusions: The present study presents the first evidence that Rhazya stricta and its active strongly basic alkaloid fraction induce the chemopreventative enzyme, Nqo1 through Nrf2-dependent mechanism.

KW - Chemoprevention

KW - Nqo1

KW - Nuclear factor erythroid 2-related factor 2

KW - Rhazya stricta

UR - http://www.scopus.com/inward/record.url?scp=84868212358&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84868212358&partnerID=8YFLogxK

U2 - 10.1016/j.jep.2012.09.032

DO - 10.1016/j.jep.2012.09.032

M3 - Article

C2 - 23026305

AN - SCOPUS:84868212358

VL - 144

SP - 416

EP - 424

JO - Journal of Ethnopharmacology

JF - Journal of Ethnopharmacology

SN - 0378-8741

IS - 2

ER -