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Mignerot L, Gimond C, Bolelli L, Bouleau C, Sandjak A, Boulin T, Braendle C. Natural variation in the Caenorhabditis elegans egg-laying circuit modulates an intergenerational fitness trade-off. eLife 2024; 12:RP88253. [PMID: 38564369 PMCID: PMC10987095 DOI: 10.7554/elife.88253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024] Open
Abstract
Evolutionary transitions from egg laying (oviparity) to live birth (viviparity) are common across various taxa. Many species also exhibit genetic variation in egg-laying mode or display an intermediate mode with laid eggs containing embryos at various stages of development. Understanding the mechanistic basis and fitness consequences of such variation remains experimentally challenging. Here, we report highly variable intra-uterine egg retention across 316 Caenorhabditis elegans wild strains, some exhibiting strong retention, followed by internal hatching. We identify multiple evolutionary origins of such phenotypic extremes and pinpoint underlying candidate loci. Behavioral analysis and genetic manipulation indicates that this variation arises from genetic differences in the neuromodulatory architecture of the egg-laying circuitry. We provide experimental evidence that while strong egg retention can decrease maternal fitness due to in utero hatching, it may enhance offspring protection and confer a competitive advantage. Therefore, natural variation in C. elegans egg-laying behaviour can alter an apparent trade-off between different fitness components across generations. Our findings highlight underappreciated diversity in C. elegans egg-laying behavior and shed light on its fitness consequences. This behavioral variation offers a promising model to elucidate the molecular changes in a simple neural circuit underlying evolutionary shifts between alternative egg-laying modes in invertebrates.
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Affiliation(s)
| | | | | | | | - Asma Sandjak
- Université Côte d’Azur, CNRS, Inserm, IBVNiceFrance
| | - Thomas Boulin
- Institut NeuroMyoGène, CNRS, Inserm, Université de LyonLyonFrance
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Min H, Kim J, Lee M, Kang S, Shim YH. Methionine Supplementation Alleviates the Germ Cell Apoptosis Increased by Maternal Caffeine Intake in a C. elegans Model. Nutrients 2024; 16:894. [PMID: 38542805 PMCID: PMC10974396 DOI: 10.3390/nu16060894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 03/14/2024] [Accepted: 03/17/2024] [Indexed: 04/01/2024] Open
Abstract
Caffeine (1,3,7-trimethylxanthine) is a widely consumed bioactive substance worldwide. Our recent study showed that a reduction in both reproduction and yolk protein production (vitellogenesis) caused by caffeine intake were improved by vitamin B12 supplementation, which is an essential co-factor in methionine metabolism. In the current study, we investigated the role of methionine in the reproduction of caffeine-ingested animals (CIAs). We assessed the effect of methionine metabolism on CIAs and found that caffeine intake decreased both methionine levels and essential enzymes related to the methionine cycle. Furthermore, we found that the caffeine-induced impairment of methionine metabolism decreased vitellogenesis and increased germ cell apoptosis in an LIN-35/RB-dependent manner. Interestingly, the increased germ cell apoptosis was restored to normal levels by methionine supplementation in CIAs. These results indicate that methionine supplementation plays a beneficial role in germ cell health and offspring development by regulating vitellogenesis.
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Affiliation(s)
| | | | | | | | - Yhong-Hee Shim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Republic of Korea; (H.M.); (J.K.); (M.L.); (S.K.)
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Li J, Dai L, Feng Y, Cao Z, Ding Y, Xu H, Xu A, Du H. Multigenerational effects and mutagenicity of three flame retardants on germ cells in Caenorhabditis elegans. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 269:115815. [PMID: 38091675 DOI: 10.1016/j.ecoenv.2023.115815] [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: 09/10/2023] [Revised: 11/14/2023] [Accepted: 12/09/2023] [Indexed: 01/12/2024]
Abstract
Flame retardants (FRs) have raised public concerns because of their environmental persistence and negative impacts on human health. Recent evidence has revealed that many FRs exhibit reproductive toxicities and transgenerational impacts, whereas the toxic effects of FRs on germ cells remain barely explored. Here we investigated the multigenerational effects of three flame retardants (TBBPA, TCEP and TCPP) on germ cell development in Caenorhabditis elegans, and examined the germ cell mutagenicity of these FRs by using whole genome sequencing. Parental exposure to three FRs markedly increased germ cell apoptosis, and impeded oogenesis in F1-F6 offspring. In addition, the double-increased mutation frequencies observed in progeny genomes uncover the mutagenic actions of FRs on germ cells. Analysis of mutation spectra revealed that these FRs predominantly induced point mutations at A:T base pairs, whereas both small and large indels were almost unaffected. These results revealed the long-term effects of FRs on development and genomic stability of germ cells, which may pose risks to environmental organisms and human reproductive health. Taken together, our findings suggest that germ cell mutagenicity should be carefully examined for the environmental risk assessment of FRs and other emerging pollutants.
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Affiliation(s)
- Jiali Li
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, Anhui, China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China
| | - Linglong Dai
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Science Island Branch, Graduate School of USTC, Hefei 230026, Anhui, China
| | - Yu Feng
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Science Island Branch, Graduate School of USTC, Hefei 230026, Anhui, China
| | - Zhenxiao Cao
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, Anhui, China
| | - Yuting Ding
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, Anhui, China
| | - Hao Xu
- Department of Neurosurgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, Anhui, China
| | - An Xu
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China.
| | - Hua Du
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, China.
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Qu Z, Liu L, Wu X, Guo P, Yu Z, Wang P, Song Y, Zheng S, Liu N. Cadmium-induced reproductive toxicity combined with a correlation to the oogenesis process and competing endogenous RNA networks based on a Caenorhabditis elegans model. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 268:115687. [PMID: 37976926 DOI: 10.1016/j.ecoenv.2023.115687] [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: 08/03/2023] [Revised: 11/01/2023] [Accepted: 11/11/2023] [Indexed: 11/19/2023]
Abstract
Accumulation of the heavy metal Cadmium (Cd) in the ovaries and placenta can affect the structure and function of these organs and induce female reproductive toxicity. This toxicity may be due to Cd's similarity to estrogen and its ability to disrupt endocrine systems. However, the exact molecular mechanism by which Cd causes reproductive toxicity at the transcriptome level remains poorly understood. Hence, this study aimed to observe Cd-induced reproductive damage at the gene level, scrutinize the repercussions of Cd exposure on oogenesis, and explicate the putative pathogenesis of Cd-induced oogenesis based on Caenorhabditis elegans (C. elegans) as an in vivo model. The results showed that Cd exposure significantly decreased the number of offspring and prolonged the reproductive span of C. elegans. Cd exposure also reduced the number of cells in mitosis and the pachytene and diakinesis stages of meiosis, thereby disrupting oogenesis. Combined with transcriptional sequencing and bioinformatics analysis, a total of 3167 DEmRNAs were identified. Regarding gene expression, cul-6, mum-2, and vang-1 were found to be related to Cd-induced reproductive toxicity, and their competing endogenous RNA networks were constructed. We observed that mutations of mom-2 and vang-1 in the Wnt pathway could induce susceptibility to Cd-caused meiosis injury. In conclusion, the results indicated that Cd could impair the oogenesis of C. elegans and the Wnt pathway might serve as a protective mechanism against Cd reproductive toxicity. These findings contribute to a better understanding of the damaging effects and molecular biological mechanisms of Cd on the human reproductive system.
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Affiliation(s)
- Zhi Qu
- School of Nursing and Health, Henan University, Kaifeng 475004, PR China
| | - Limin Liu
- College of Public Health, Zhengzhou University, Zhengzhou 540001, PR China
| | - Xiaoliang Wu
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, PR China
| | - Peisen Guo
- College of Public Health, Zhengzhou University, Zhengzhou 540001, PR China
| | - Zengli Yu
- College of Public Health, Zhengzhou University, Zhengzhou 540001, PR China
| | - Peixi Wang
- School of Nursing and Health, Henan University, Kaifeng 475004, PR China
| | - Yuzhen Song
- School of Nursing and Health, Henan University, Kaifeng 475004, PR China
| | - Shanqing Zheng
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, PR China.
| | - Nan Liu
- School of Nursing and Health, Henan University, Kaifeng 475004, PR China; College of Public Health, Zhengzhou University, Zhengzhou 540001, PR China; Institute of Environment and Health, South China Hospital of Shenzhen University, Shenzhen 518116, PR China.
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Davis GM, Hipwell H, Boag PR. Oogenesis in Caenorhabditis elegans. Sex Dev 2023; 17:73-83. [PMID: 37232019 PMCID: PMC10659005 DOI: 10.1159/000531019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 05/01/2023] [Indexed: 05/27/2023] Open
Abstract
BACKGROUND The nematode, Caenorhabditis elegans has proven itself as a valuable model for investigating metazoan biology. C. elegans have a transparent body, an invariant cell lineage, and a high level of genetic conservation which makes it a desirable model organism. Although used to elucidate many aspects of somatic biology, a distinct advantage of C. elegans is its well annotated germline which allows all aspects of oogenesis to be observed in real time within a single animal. C. elegans hermaphrodites have two U-shaped gonad arms which produce their own sperm that is later stored to fertilise their own oocytes. These two germlines take up much of the internal space of each animal and germ cells are therefore the most abundant cell present within each animal. This feature and the genetic phenotypes observed for mutant worm gonads have allowed many novel findings that established our early understanding of germ cell dynamics. The mutant phenotypes also allowed key features of meiosis and germ cell maturation to be unveiled. SUMMARY This review will focus on the key aspects that make C. elegans an outstanding model for exploring each feature of oogenesis. This will include the fundamental steps associated with germline function and germ cell maturation and will be of use for those interested in exploring reproductive metazoan biology. KEY MESSAGES Since germ cell biology is highly conserved in animals, much can be gained from study of a simple metazoan like C. elegans. Past findings have enhanced understanding on topics that would be more laborious or challenging in more complex animal models.
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Affiliation(s)
- Gregory M. Davis
- Institute of Innovation, Science and Sustainability, Federation University, Churchill, VIC, Australia
| | - Hayleigh Hipwell
- Department of Biochemistry and Molecular Biology, Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia
| | - Peter R. Boag
- Department of Biochemistry and Molecular Biology, Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia
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Shi C, Wang C, Zeng L, Peng Y, Li Y, Hao H, Zheng Y, Chen C, Chen H, Zhang J, Xiang M, Huang Y, Li H. Triphenyl phosphate induced reproductive toxicity through the JNK signaling pathway in Caenorhabditis elegans. JOURNAL OF HAZARDOUS MATERIALS 2023; 446:130643. [PMID: 36586333 DOI: 10.1016/j.jhazmat.2022.130643] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 12/09/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Triphenyl phosphate (TPHP) is a widely used aryl organophosphate flame retardant (OPFR) that has attracted attention due to its frequent detection in the environment and living organisms. To date, the reproductive toxicity of TPHP has been investigated in organisms, but its molecular mechanisms are not fully understood. Caenorhabditis elegans (C. elegans) is the ideal animal for the study of reproductive toxicity following environmental pollutants, with short generation times, intact reproductive structures, and hermaphroditic fertilization. This study aimed to explore the reproductive dysfunction and molecular mechanisms induced by TPHP exposure in C. elegans. Specifically, exposure to TPHP resulted in a reduction in the number of eggs laid and developing embryos in utero, an increase in the number of apoptotic gonadal cells, and germ cell cycle arrest. The JNK signaling pathway is a potential pathway inducing reproductive toxicity following TPHP exposure based on transcriptome sequencing (RNA-seq). Moreover, TPHP exposure induced down-regulation of vhp-1 and kgb-2 gene transcription levels, and the knockout of vhp-1 and kgb-2 in the mutant strains exhibited more severe toxicity in apoptotic gonad cells, embryos, and eggs developing in utero, suggesting that vhp-1 and kgb-2 genes play a crucial role in TPHP-induced reproductive toxicity. Our data provide convergent evidence showing that TPHP exposure results in reproductive dysfunction through the JNK signaling pathway and improve our understanding of the ecotoxicity and toxicological mechanisms of aryl-OPFRs.
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Affiliation(s)
- Chongli Shi
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Chen Wang
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
| | - Lingjun Zeng
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yi Peng
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yeyong Li
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Haibin Hao
- Department of Critical Care Medicine, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing 210000, China
| | - Yang Zheng
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Chao Chen
- State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
| | - Haibo Chen
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences. Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Jin Zhang
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Minghui Xiang
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yuan Huang
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Hui Li
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
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7
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Intraovarian condensed platelet cytokines for infertility and menopause-Mirage or miracle? Biochimie 2023; 204:41-47. [PMID: 36075561 DOI: 10.1016/j.biochi.2022.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/30/2022] [Accepted: 08/31/2022] [Indexed: 01/12/2023]
Abstract
On a therapeutic landscape unchanged since the 1980's, oocyte donation with IVF still stands as the solitary medical answer to diminished reserve and premature ovarian insufficiency. In 2016, intraovarian platelet-rich plasma (PRP) crossed the horizon as a hopeful reply to these intertwined problems. The once remote mirage of platelet cytokine effects on gene regulation or telomere stabilization has been brought into sharper focus, with current work clarifying how PRP corrects oxidative stress, rectifies tissue hypoxia, downregulates apoptosis, and enhances cellular metabolism. Not yet ready for routine use, this innovative treatment has already offered at least one point of early consensus: How intraovarian PRP results should be classified-Patients are either responders or non-responders. From this it is intriguing that no published PRP protocol has ever reported a supranormal ovarian rebound or hyperstimulation effect. This might be explained by baseline age-related ovarian conditions prevalent among poor responders, but since dysregulated or malignant transformations are also missing in other tissue contexts following autologous PRP treatment, the contribution of some platelet product which intrinsically delimits regenerative action cannot be discounted. Here we summarize results with recent experimental and clinical platelet research, framing those most likely to help advance reproductive endocrinology practice.
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Cao Z, Wang M, Zhou T, Xu A, Du H. Whole-Genome Sequencing Reveals Germ Cell Mutagenicity of α-Endosulfan in Caenorhabditis elegans. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:16024-16032. [PMID: 36239620 DOI: 10.1021/acs.est.2c06817] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Endosulfan is an extensively used organochlorine pesticide around the world, which was classified as a persistent organic pollutant (POP) in 2009. Although previous studies have documented the reproductive toxicity of endosulfan in a variety of organisms, little is known about the influence of endosulfan on the genome stability of germ cells and nonexposed progeny. Here we applied whole-genome sequencing to explore the germ cell mutagenicity of α-endosulfan in Caenorhabditis elegans (C. elegans). We found that, although low doses of α-endosulfan exhibited a minor effect on the reproductive capacity of C. elegans, chronic exposure to 1 μM α-endosulfan significantly increased the mutation frequencies of nonexposed progeny. Further analysis of genome-wide mutation spectra demonstrated that α-endosulfan preferentially elicited A:T → G:C substitutions and clustered mutations. By using worms deficient in DNA damage response genes, our results suggest the involvement of translesion synthesis polymerase η in modulating α-endosulfan-induced mutations in germ cells. Together, these observations reveal the germ cell mutagenicity of α-endosulfan in C. elegans and the possible underlying mechanism. In addition, our findings implicate that germ cell mutagenicity might be a necessary consideration for the health risk assessment of environmental chemicals such as POPs.
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Affiliation(s)
- Zhenxiao Cao
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, Anhui, P. R. China
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, P. R. China
| | - Meimei Wang
- Department of Pathophysiology, School of Basic Medical Science, Anhui Medical University, No. 81 Mei-Shan Rd, Hefei 230032, Anhui, P. R. China
| | - Tong Zhou
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, P. R. China
| | - An Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, P. R. China
| | - Hua Du
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, CAS, Hefei 230031, Anhui, P. R. China
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Huang CW, Yen PL, Kuo YH, Chang CH, Liao VHC. Nanoplastic exposure in soil compromises the energy budget of the soil nematode C. elegans and decreases reproductive fitness. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 312:120071. [PMID: 36055456 DOI: 10.1016/j.envpol.2022.120071] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/20/2022] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
Environmental nanoplastics (NPs) can accumulate in soils, posing a potential risk to soil ecosystems. However, the ecotoxicity of NPs for soil organisms has received little research attention. This study investigated whether NP exposure in soil leads to reproductive decline in the soil nematode Caenorhabditis elegans and sought to determine the mechanisms by which it may occur. Wild-type N2 C. elegans L1 larvae were exposed to various concentrations of nano-sized polystyrene (100 nm) in soil (0, 1, 10, 100, and 1000 mg/kg dry weight) for 96 h. We show that nano-sized polystyrene (100 nm) labeled with red fluorescence significantly accumulated in the intestine of C. elegans in a dose-dependent fashion via soil exposure (8%-47% increase). In addition, NP soil exposure led to 7%-33% decline in the number of eggs in utero and 2.6%-4.4% decline in the egg hatching percentage. We also find that the number of germ cell corpses (31%-55% increase) and the mRNA levels of germline apoptosis marker gene ced-3 (14%-31% increase) were significantly higher with greater NP soil exposure (10, 100, and 1000 mg/kg), while intracellular ATP levels were significantly reduced. Finally, the DEBtox model, which is based on the dynamic energy budget theory, was applied to show that the increased reproductive costs for C. elegans caused by NPs in soil are associated with energy depletion and reproductive decline. The threshold value (4.18 × 10-6 mg/kg) for the energy budget also highlighted the potential high reproductive risk posed by NPs in terrestrial ecosystems. Our study provides new insights into how soil organisms interact with NPs in soil ecosystems.
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Affiliation(s)
- Chi-Wei Huang
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan
| | - Pei-Ling Yen
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yu-Hsuan Kuo
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Chun-Han Chang
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Vivian Hsiu-Chuan Liao
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 10617, Taiwan.
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Lee M, Youn E, Kang K, Shim YH. 3,3'-Diindolylmethane Supplementation Maintains Oocyte Quality by Reducing Oxidative Stress and CEP-1/p53-Mediated Regulation of Germ Cells in a Reproductively Aged Caenorhabditis elegans Model. Antioxidants (Basel) 2022; 11:950. [PMID: 35624814 PMCID: PMC9137721 DOI: 10.3390/antiox11050950] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/06/2022] [Accepted: 05/08/2022] [Indexed: 11/20/2022] Open
Abstract
In recent decades, maternal age at first birth has increased, as has the risk of infertility due to rapidly declining oocyte quality with age. Therefore, an understanding of female reproductive aging and the development of potential modulators to control oocyte quality are required. In this study, we investigated the effects of 3,3'-diindolylmethane (DIM), a natural metabolite of indole-3-cabinol found in cruciferous vegetables, on fertility in a Caenorhabditis elegans model. C. elegans fed DIM showed decreased mitochondrial dysfunction, oxidative stress, and chromosomal aberrations in aged oocytes, and thus reduced embryonic lethality, suggesting that DIM, a dietary natural antioxidant, improves oocyte quality. Furthermore, DIM supplementation maintained germ cell apoptosis (GCA) and germ cell proliferation (GCP) in a CEP-1/p53-dependent manner in a reproductively aged C. elegans germ line. DIM-induced GCA was mediated by the CEP-1-EGL-1 pathway without HUS-1 activation, suggesting that DIM-induced GCA is different from DNA damage-induced GCA in the C. elegans germ line. Taken together, we propose that DIM supplementation delays the onset of reproductive aging by maintaining the levels of GCP and GCA and oocyte quality in a reproductively aged C. elegans.
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Affiliation(s)
- Mijin Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
| | - Esther Youn
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
| | - Kyungsu Kang
- Natural Product Informatics Research Center, Korea Institute of Science and Technology, Gangneung 25451, Gangwon-do, Korea;
| | - Yhong-Hee Shim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 05029, Korea; (M.L.); (E.Y.)
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