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Gold and Silver Nanoparticles Biomimetically Synthesized Using Date Palm Pollen Extract-Induce Apoptosis and Regulate p53 and Bcl-2 Expression in Human Breast Adenocarcinoma Cells

Biological Trace Element Research volume 186, pages 122–134 (2018)Cite this article

Abstract

Recently, several attempts have been made to use the phytopharmaceuticals from plant extracts as reducing, capping and stabilizing agents for the biomimetic synthesis of various metal nanoparticles conjugated to the phytopharmaceuticals. These biogenic metal nanoparticles are non-toxic and can be used as contrast agents, drug delivery vehicles and photothermal agents for cancer therapy. Herein, we report the synthesis of both silver and gold nanoparticles using the pollen extract of Phoenix dactylifera (Date Palm), characterization using UV-visible spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, quantitation of phytochemicals capping the nanoparticles using Folin – Ciocalteu’s method, cytotoxicity studies on MCF-7 breast cancer cells, cancer cell death analysis using fluorescent microscopy, and modulation of expression of the pro-apoptotic p53 and anti-apoptotic Bcl-2 proteins. The biosynthesis resulted in stable and poly-dispersed silver nanoparticles and gold nanoparticles, exhibiting strong and broad surface plasmon absorption peaks. The elemental analysis confirmed the presence of gold and silver of high purity and also the organic moieties from the plant extract acting as capping and stabilizing agents. The biogenic nanoparticles also exhibited dose-dependent cytotoxicity on MCF-7 cells and showed signs of apoptotic cell death. Immunoassays revealed the upregulation of the pro-apoptotic protein p53 and down-regulation of the anti-apoptotic protein Bcl-2 after the nanoparticle treatment.

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Acknowledgements

We would like to acknowledge Dr. Firdos Alam Khan, Chairperson of School of Life Sciences, Manipal University, Dubai for his cooperation and encouragement; Dr. Taher Rizvi, Professor, College of Medicine and Health Sciences, UAE University; Al-Ain for providing us the cell lines; Dr. Elango, Researcher at Masdar Institute, Abu Dhabi for helping us with some of the characterization studies; Dr. N.K. Rao, Plant Genetic Resources Scientist at the International Center for Biosaline Agriculture (ICBA) for arranging the plant source; Dr. Zakiya Ansari, Assistant Professor – English Language Teaching, Manipal University, Dubai for proof-reading the manuscript; and the undergraduate students Ms. Sajidah Hashim and Ms. Sahadiya Zubair for their support.

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  1. School of Life Sciences, Manipal University Dubai Campus,, G-04-Academic city, P.O. Box 345050, Dubai, UAE

    Hussaina Banu, S.M. Faheem, Raees Ismail, Vinita Singh, Zahra Saadatmand, Saad Sultan Khan, Kavya Narayanan & Alma Raheem

  2. Cancer Genetics and Nanomedicine Laboratory, Department of Biomedical Science, Bharathidasan University, P.O. Box 620024, Tiruchirappalli, India

    Hussaina Banu & Kumpati Premkumar

  3. Department of Engineering, Higher Colleges of Technology, Abu Dhabi Men’s College, P.O. Box 25035, Abu Dhabi, UAE

    N. Renuka

  4. Holistic International Testing Services FZ-LLC, G04-A1, Ground Floor, Dubiotech Laboratory Building, P.O. Box 500767, Dubai, UAE

    Geetha Vasanthakumar

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  1. Hussaina Banu
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Banu, H., Renuka, N., Faheem, S. et al. Gold and Silver Nanoparticles Biomimetically Synthesized Using Date Palm Pollen Extract-Induce Apoptosis and Regulate p53 and Bcl-2 Expression in Human Breast Adenocarcinoma Cells. Biol Trace Elem Res 186, 122–134 (2018). https://doi.org/10.1007/s12011-018-1287-0

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Keywords

  • Nanoparticles
  • Phytochemicals
  • Phoenix dactylifera
  • Breast cancer
  • Cytotoxicity
  • Apoptosis