title: Rhamnolipids functionalized AgNPs-induced oxidative stress and modulation of toxicity pathway genes in cultured MCF-7 cells.
abstract: Rhamnolipids extracted from Pseudomonas aeruginosa strain JS-11 were utilized for synthesis of stable silver nanoparticles (Rh-AgNPs). The Rh-AgNPs (23 nm) were characterized by Fourier transform infra-red (FTIR) spectroscopy, atomic force microscopy (AFM) and transmission electron microscopy (TEM). The cytotoxicity assays suggested significant decrease in viability of Rh-AgNPs treated human breast adenocarcinoma (MCF-7) cells, compared with normal human peripheral blood mononuclear (PBMN) cells. Flow cytometry data revealed 1.25-fold (p<0.05) increase in the fluorescence of 2',7'-dichlorofluorescein (DCF) at 0.25 μg/mL. However, at Rh-AgNPs concentrations of 0.5 and 1.0 μg/mL, much lesser fluorescence was noticed, which is attributed to cell death. Results with the fluorescent probe Rh123 demonstrated change in inner mitochondrial membrane and dissipation of membrane potential. The cell cycle analysis suggested 19.9% (p<0.05) increase in sub-G1 peak with concomitant reduction in G1 phase at 1 μg/mL of Rh-AgNPs, compared to 2.7% in untreated control. The real-time RT(2) Profiler™ PCR array data elucidated the overexpression of seven oxidative stress and DNA damage pathways genes viz. BAX, BCl2, Cyclin D1, DNAJA1, E2F transcription factor 1, GPX1 and HSPA4, associated with apoptosis signaling, proliferation and carcinogenesis, pro inflammatory and heat shock responses in Rh-AgNPs treated cells. Thus, the increased ROS production, mitochondrial damage and appearance of sub-G1 (apoptotic) population suggested the anti-proliferative activity, and role of oxidative stress pathway genes in Rh-AgNPs induced death of MCF-7 cancer cells.
authors.affiliation: Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
authors.forename: Sourabh
authors.initials: S
authors.lastname: Dwivedi
authors.affiliation: Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Quaiser
authors.initials: Q
authors.lastname: Saquib
authors.affiliation: Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Abdulaziz A
authors.initials: AA
authors.lastname: Al-Khedhairy
authors.affiliation: Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Javed
authors.initials: J
authors.lastname: Ahmad
authors.affiliation: Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
authors.forename: Maqsood A
authors.initials: MA
authors.lastname: Siddiqui
authors.affiliation: Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India. Electronic address: musarratj1@yahoo.com.
authors.forename: Javed
authors.initials: J
authors.lastname: Musarrat
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016923:Cell Death; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D008055:Lipids / Q000737:chemistry / Q000494:pharmacology*; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D053768:Metal Nanoparticles; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012834:Silver / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D008055:Lipids; D017382:Reactive Oxygen Species; D012834:Silver
keywords: Cytotoxicity; Gene expression; ROS; Rhamnolipid; Silver nanoparticles; XRD