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Preparation of Naringenin Solution for In Vivo Application
08:18

Preparation of Naringenin Solution for In Vivo Application

Published on: August 10, 2021

The citrus flavanone naringenin suppresses CYP1B1 transactivation through antagonising xenobiotic-responsive element

Ching Ho Poon1, Tsz Yan Wong, Yanfei Wang

  • 1Molecular Biotechnology Programme, School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.

The British Journal of Nutrition
|September 1, 2012
PubMed

Insights

Naringenin, found in citrus fruits, inhibits the enzyme Cytochrome P450 (CYP) 1B1, which transforms environmental toxicants into cancer-causing agents. This suggests fruit consumption may protect against carcinogens by reducing toxic biotransformation.

Area of Science:

  • Biochemistry
  • Environmental Health
  • Nutritional Science

Background:

  • Environmental toxicants, like polycyclic aromatic hydrocarbons (PAH), increase cancer risk by undergoing biotransformation into genotoxic agents.
  • Cytochrome P450 (CYP) 1B1 is a key enzyme responsible for activating certain toxicants.
  • Dietary intake of fruits and vegetables is associated with reduced cancer risk, with naringenin in citrus fruits being a notable compound.

Purpose of the Study:

  • To investigate the effect of naringenin on the regulation of CYP1B1 activity and expression.
  • To determine if naringenin interferes with the transcriptional regulation of CYP1B1.

Main Methods:

  • Enzyme inhibition assays were performed using MCF-7 cells to assess naringenin's effect on CYP1B1 and CYP1A1 activity.
  • Quantitative PCR was used to measure CYP1B1 mRNA expression following treatment with naringenin and 7,12-dimethylbenz(α)anthracene (DMBA).
  • Reporter gene assays and electrophoretic mobility shift assays (EMSA) were employed to examine DNA binding to the CYP1B1 promoter regions (ERE and XRE).

Main Results:

  • Naringenin demonstrated significant inhibition of CYP1B1 activity at concentrations of 5 μm and above, with no effect on CYP1A1.
  • Naringenin treatment reduced DMBA-induced CYP1B1 mRNA expression, indicating suppression at the transcriptional level.
  • Naringenin was found to counteract DMBA-induced binding to the xenobiotic-responsive element (XRE) in the CYP1B1 promoter region.

Conclusions:

  • Naringenin effectively inhibits CYP1B1 activity and suppresses its gene expression, particularly by interfering with XRE binding.
  • These findings support the protective role of fruit consumption against carcinogenesis by mitigating the biotransformation of harmful environmental toxicants.

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