1
|
Hosseinzadeh M, Postigo C, Porte C. Toxicity and underlying lipidomic alterations generated by a mixture of water disinfection byproducts in human lung cells. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170331. [PMID: 38278255 DOI: 10.1016/j.scitotenv.2024.170331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 01/28/2024]
Abstract
Complex mixtures of disinfection by-products (DBPs) are present in disinfected waters, but their mixture toxicity has been rarely described. Apart from ingestion, DBP exposure can occur through inhalation, which may lead to respiratory effects in highly exposed individuals. However, the underlying biological mechanisms have yet to be elucidated. This study aimed to investigate the toxicity of a mixture of 10 DBPs, including haloacetic acids and haloaromatics, on human alveolar A549 cells by assessing their cytotoxicity, genotoxicity, and impact on the cell lipidome. A DBP mixture up to 50 μM slightly reduced cell viability, induced the generation of reactive oxygen species (ROS) up to 3.5-fold, and increased the frequency of micronuclei formation. Exposure to 50 μM DBP mixture led to a significant accumulation of triacylglycerides and a decrease of diacylglycerides and phosphatidylcholines in A549 cells. Lipidomic profiling of extracellular vesicles (EVs) released in the culture medium revealed a marked increase in cholesterol esters, sphingomyelins, and other membrane lipids. Overall, these alterations in the lipidome of cells and EVs may indicate a disruption of lipid homeostasis, and thus, potentially contribute to the respiratory effects associated with DBP exposure.
Collapse
Affiliation(s)
- Mahboubeh Hosseinzadeh
- Environmental Chemistry Department, Institute of Environmental Research and Water Assessment, IDAEA -CSIC-, C/ Jordi Girona, 18-26, 08034 Barcelona, Spain.
| | - Cristina Postigo
- Technologies for Water Management and Treatment Research Group, Department of Civil Engineering, University of Granada, Avda. Severo Ochoa s/n, Granada 18071, Spain; Institute for Water Research (IdA), University of Granada, Ramón y Cajal 4, 18071 Granada, Spain
| | - Cinta Porte
- Environmental Chemistry Department, Institute of Environmental Research and Water Assessment, IDAEA -CSIC-, C/ Jordi Girona, 18-26, 08034 Barcelona, Spain
| |
Collapse
|
2
|
Qin M, Huang L, Li M, Shao T, Zhang J, Jiang X, Shao C, Zhao C, Pan Y, Zhou Q, Wang Y, Liu XM, Qiu J. Immunotoxicity Evaluation of Trihalophenolic Disinfection By-Products in Mouse and Human Mononuclear Macrophage Systems: The Role of RNA Epitranscriptomic Modification in Mammalian Immunity. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:127023. [PMID: 38157273 PMCID: PMC10756339 DOI: 10.1289/ehp11329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 10/15/2023] [Accepted: 11/14/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND 2,4,6-Trichlorophenol (TCP), 2,4,6-tribromophenol (TBP) and 2,4,6-triiodophenol (TIP) are three widely detected trihalophenolic disinfection by-products (DBPs). Previous studies have mainly focused on the carcinogenic risk and developmental toxicity of 2,4,6-trihalophenols. Very little is known about their immunotoxicity in mammals. OBJECTIVES We investigated the effects of 2,4,6-trihalophenols on mammalian immunity using a mouse macrophage model infected with bacteria or intracellular parasites and aimed to elucidate the underlying mechanisms from an epitranscriptomic perspective. The identified mechanisms were further validated in human peripheral blood mononuclear cells (PBMCs). METHODS The mouse macrophage cell line RAW264.7 and primary mouse peritoneal macrophages were exposed to different concentrations of TCP, TBP, and TIP. The pro-inflammatory marker Ly6C, the survival of the bacterium Escherichia coli (E. coli), and the parasite burden of Toxoplasma gondii (T. gondii) were assessed. Furthermore, the global gene expression profiling of macrophages following exposure to 2,4,6-trihalophenols was obtained through RNA-sequencing (RNA-seq). The effects of 2,4,6-trihalophenols on RNA N 6 -methyladenosine (m 6 A ) methyltransferases and total RNA m 6 A levels were evaluated using Western blotting and dot blot, respectively. Transcriptome-wide m 6 A methylome was analyzed by m 6 A -seq . In addition, expression of m 6 A regulators and total RNA m 6 A levels in human PBMCs exposed to 2,4,6-trihalophenols were detected using quantitative reverse transcriptase polymerase chain reaction and dot blot, respectively. RESULTS Mouse macrophages exposed to TCP, TBP, or TIP had lower expression of the pro-inflammatory marker Ly6C, with a greater difference from control observed for TIP-exposed cells. Consistently, macrophages exposed to such DBPs, especially TIP, were susceptible to infection with the bacterium E. coli and the intracellular parasite T. gondii, indicating a compromised ability of macrophages to defend against pathogens. Intriguingly, macrophages exposed to TIP had significantly greater m 6 A levels, which correlated with the greater expression levels of m 6 A methyltransferases. Macrophages exposed to each of the three 2,4,6-trihalophenols exhibited transcriptome-wide redistribution of m 6 A . In particular, the m 6 A peaks in genes associated with immune-related pathways were altered after exposure. In addition, differences in m 6 A were also observed in human PBMCs after exposure to 2,4,6-trihalophenols. DISCUSSION These findings suggest that 2,4,6-trihalophenol exposure impaired the ability of macrophages to defend against pathogens. This response might be associated with notable differences in m 6 A after exposure. To the best of our knowledge, this study presents the first m 6 A landscape across the transcriptome of immune cells exposed to pollutants. However, significant challenges remain in elucidating the mechanisms by which m 6 A mediates immune dysregulation in infected macrophages after 2,4,6-trihalophenol exposure. https://doi.org/10.1289/EHP11329.
Collapse
Affiliation(s)
- Min Qin
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
- Department of Pathology, Children’s Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Linyuan Huang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
- School of Pharmacy, Jiangsu Health Vocational College, Nanjing, Jiangsu, China
| | - Meishuang Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Tianye Shao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jun Zhang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Xiaoqin Jiang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Chenlu Shao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Chengsi Zhao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yang Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Qing Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Yong Wang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-Min Liu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Jingfan Qiu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| |
Collapse
|