Nickel Oxide Nanoparticles Trigger Caspase- and Mitochondria

Jan 18, 2019 - The execution of yeast cell death induced by NiO NPs is Yca1p ... mutants, which supports the involvement of mitochondria in the cell d...
3 downloads 0 Views 471KB Size
Subscriber access provided by TULANE UNIVERSITY

Article

Nickel oxide (NiO) nanoparticles trigger caspase- and mitochondriadependent apoptosis in yeast Saccharomyces cerevisiae Cátia A. Sousa, Helena MVM Soares, and Eduardo V. Soares Chem. Res. Toxicol., Just Accepted Manuscript • DOI: 10.1021/acs.chemrestox.8b00265 • Publication Date (Web): 18 Jan 2019 Downloaded from http://pubs.acs.org on January 20, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Chemical Research in Toxicology

Nickel oxide (NiO) nanoparticles trigger caspase- and mitochondria-dependent apoptosis in yeast Saccharomyces cerevisiae

Cátia A. Sousa†,‡,§, Helena M.V.M. Soares§ and Eduardo V. Soares†,‡*

†Bioengineering Laboratory-CIETI,

Chemical Engineering Department, ISEP-School of Engineering

of Polytechnic Institute of Porto, Rua Dr António Bernardino de Almeida, 431, 4249-015 Porto, Portugal ‡CEB-Centre

of Biological Engineering, University of Minho, 4710-057 Braga, Portugal

§REQUIMTE/LAQV,

Departamento de Engenharia Química, Faculdade de Engenharia,

Universidade do Porto, rua Dr. Roberto Frias, 4200-465, Porto, Portugal

Keywords: apoptosis, caspase, mitochondrial dysfunction; regulated cell death; Saccharomyces cerevisiae; toxicity.

*Author

for correspondence:

Eduardo V. Soares e-mail: [email protected]; Tel: 351-22-8340500

1 ACS Paragon Plus Environment

Chemical Research in Toxicology 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 36

Abstract The expansion of industrial use of nickel oxide (NiO) nanoparticles (NPs) raises concerns about their potential adverse effects. The present work aimed to investigate the mechanisms of toxicity induced by NiO NPs, using the yeast Saccharomyces cerevisiae, as cell model. Yeast cells exposed to NiO NPs exhibited typical hallmarks of regulated cell death (RCD) by apoptosis [loss of cell proliferation capacity (cell viability), exposure of phosphatidylserine at the outer cytoplasmic membrane leaflet, nuclear chromatin condensation and DNA damage] in a process which required de novo protein synthesis. The execution of yeast cell death induced by NiO NPs is Yca1p metacaspase-dependent. NiO NPs also induced the reduction of the mitochondrial membrane potential and the increase of the frequency of respiratory deficient mutants, which supports the involvement of mitochondria in the cell death process. Cells deficient in the apoptosis-inducing factor (aif1Δ) displayed higher tolerance to NiO NPs, which reinforces the involvement of mitochondria in the RCD by apoptosis. In resume, this study shows that NiO NPs induce caspaseand mitochondria-dependent apoptosis in yeast. The presented results warn to the possible harmful effects associated with the use of NiO NPs.

2 ACS Paragon Plus Environment

Page 3 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Chemical Research in Toxicology

Table of Content (TOC) Graphic

3 ACS Paragon Plus Environment

Chemical Research in Toxicology 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 36

INTRODUCTION Due to their unique physiochemical properties and reactivity, the metal oxide nanoparticles (NPs) are increasingly manufactured in the last decade. Nickel oxide (NiO) NPs are used for multiple applications, such as catalysts, memory cells, electrode materials in multilayer ceramic capacitors, diesel-fuel additives and pigments for ceramics and glasses.1 As the nanotechnology industry expands, the exposure to NiO NPs emerges as a significant occupational hazard. In addition, a deeper understanding of the potential impact of NiO NPs on the environment and human health is required. Adverse effects as consequence of the exposure to NiO NPs, such as, cytotoxicity, inflammation and genotoxicity in human pulmonary cells, has been reported.2-5 The International Agency for Research on Cancer classed nickel compounds as group 1 (carcinogenic to humans) and metallic nickel was classed as group 2B (possible carcinogenic to humans).6 Cell death can be classified into a not programed “accidental cell death” (ACD) and “regulated cell death” (RCD). The first subtype of cell death (ACD) occurs as a consequence of the exposure of cells to severe physical, chemical or mechanical stimuli; cells demise in an uncontrollable manner as a result of their immediate loss of structural integrity. RCD involves a genetically encoded machinery and can result from multiple signalling pathways, including apoptosis. The designation “programed cell death” (PCD) is used to refer RCD that is executed in specific physiological scenarios.7,

8

Many human diseases, such as several neurological disorders (for example,

Huntington’s, Parkinson’s and Alzheimer’s disease) and cancer are associated with the dysregulation of cell death pathways.9 In this context, it has been shown that the exposure to NiO NPs induce apoptosis in different cell lines, such as in human bronchial epithelial (BEAS-2B)

10,

lung epithelial (NCIH460) 11, liver (HepG2) 12, 13 and neuronal cells (SH-SY5Y) 14. The yeast S. cerevisiae is a relevant eukaryotic cell model in different fields, such as biochemistry, molecular and cellular biology. In the last decade, this unicellular microorganism has been used in the study of RCD.15,

16

This yeast displays some similarities (orthologues) with mammalian

4 ACS Paragon Plus Environment

Page 5 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Chemical Research in Toxicology

(including human) cells, which makes it an effective cell model to human diseases.17 In a previous work, it was found that the exposure of yeast cells of S. cerevisiae to NiO NPs induced the loss of metabolic activity and cell viability in a dose-dependent manner.18 In a subsequent work, it was observed that the loss of cell viability induced by NiO could be attributed to the intracellular generation of reactive oxygen species (ROS) and glutathione depletion.19 It is described that oxidative stress is a common denominator of RCD initiation.20 The present work aimed to characterize the cell death observed in S. cerevisiae upon exposure to NiO NPs. For this purpose, yeast cell death induced by NiO NPs was assessed by monitoring the loss of plasma membrane integrity and cell viability. Subsequently, the presence of typical morphological and biochemical features of apoptotic cell death was examined in yeast cells exposed to a cytotoxic concentration of NiO NPs. In addition, the dependence of known apoptotic regulators/executors (Yca1p and Aif1p) in the RCD NiO NPs-induced was evaluated.

EXPERIMENTAL PROCEDURES Preparation of nickel oxide nanoparticles suspensions Commercial nickel oxide (NiO) nanoparticles (NPs) (Catalogue number 637130, with a particle size