Cobalt oxide nanoparticles aggravate DNA damage and cell death in eggplant via mitochondrial swelling and NO signaling pathway. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Faisal, Mohammad; Saquib, Quaiser; Alatar, Abdulrahman; Al-Khedhairy, Abdulaziz; Ahmed, Mukhtar; Ansari, Sabiha; Alwathnani, Hend; Dwivedi, Sourabh; Musarrat, Javed; Praveen, Shelly
• Is Part Of: Biological research. Volume 49:Issue 1(2016)
• Page Start: 1
• Page End: 13
• Publication Date: 2016-12
• Subjects: Cobalt oxide nanoparticles -- Nanotoxicity -- DNA damage -- Apoptosis -- Oxidative stress; Biology, Experimental -- Periodicals; Biology -- Periodicals; 570.724
• DOI: 10.1186/s40659-016-0080-9
• Languages: English
• ISSNs: 0716-9760

Abstract

Abstract Background Despite manifold benefits of nanoparticles (NPs), less information on the risks of NPs to human health and environment has been studied. Cobalt oxide nanoparticles (Co3 O4 -NPs) have been reported to cause toxicity in several organisms. In this study, we have investigated the role of Co3 O4 -NPs in inducing phytotoxicity, cellular DNA damage and apoptosis in eggplant (Solanum melongena L. cv. Violetta lunga 2). To the best of our knowledge, this is the first report on Co3 O4 -NPs showing phytotoxicity in eggplant. Results The data revealed that eggplant seeds treated with Co3 O4 -NPs for 2 h at a concentration of 1.0 mg/ml retarded root length by 81.5 % upon 7 days incubation in a moist chamber. Ultrastructural analysis by transmission electron microscopy (TEM) demonstrated the uptake and translocation of Co3 O4 -NPs into the cytoplasm. Intracellular presence of Co3 O4 -NPs triggered subcellular changes such as degeneration of mitochondrial cristae, abundance of peroxisomes and excessive vacuolization. Flow cytometric analysis of Co3 O4 -NPs (1.0 mg/ml) treated root protoplasts revealed 157, 282 and 178 % increase in reactive oxygen species (ROS), membrane potential (ΔΨm ) and nitric oxide (NO), respectively. Besides, the esterase activity in treated protoplasts was also found compromised. About 2.4-fold greater level of DNA damage, as compared to untreated control was observed in Comet assay, and 73.2 % of Co3 O4 -NPs treated cells appeared apoptotic in flow cytometry based cell cycle analysis. Conclusion This study demonstrate the phytotoxic potential of Co3 O4 -NPs in terms of reduction in seed germination, root growth, greater level of DNA and mitochondrial damage, oxidative stress and cell death in eggplant. The data generated from this study will provide a strong background to draw attention on Co3 O4 -NPs environmental hazards to vegetable crops.