1
|
Spencer PS, Valdes Angues R, Palmer VS. Nodding syndrome: A role for environmental biotoxins that dysregulate MECP2 expression? J Neurol Sci 2024; 462:123077. [PMID: 38850769 DOI: 10.1016/j.jns.2024.123077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 05/15/2024] [Accepted: 05/30/2024] [Indexed: 06/10/2024]
Abstract
Nodding syndrome is an epileptic encephalopathy associated with neuroinflammation and tauopathy. This initially pediatric brain disease, which has some clinical overlap with Methyl-CpG-binding protein 2 (MECP2) Duplication Syndrome, has impacted certain impoverished East African communities coincident with local civil conflict and internal displacement, conditions that forced dependence on contaminated food and water. A potential role in Nodding syndrome for certain biotoxins (freshwater cyanotoxins plus/minus mycotoxins) with neuroinflammatory, excitotoxic, tauopathic, and MECP2-dysregulating properties, is considered here for the first time.
Collapse
Affiliation(s)
- Peter S Spencer
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Gulu University School of Medicine, Gulu, Uganda.
| | - Raquel Valdes Angues
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Valerie S Palmer
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Gulu University School of Medicine, Gulu, Uganda
| |
Collapse
|
2
|
Ge K, Du X, Liu H, Meng R, Wu C, Zhang Z, Liang X, Yang J, Zhang H. The cytotoxicity of microcystin-LR: ultrastructural and functional damage of cells. Arch Toxicol 2024; 98:663-687. [PMID: 38252150 DOI: 10.1007/s00204-023-03676-0] [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] [Received: 10/23/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024]
Abstract
Microcystin-LR (MC-LR) is a toxin produced by cyanobacteria, which is widely distributed in eutrophic water bodies and has multi-organ toxicity. Previous cytotoxicity studies have mostly elucidated the effects of MC-LR on intracellular-related factors, proteins, and DNA at the molecular level. However, there have been few studies on the adverse effects of MC-LR on cell ultrastructure and function. Therefore, research on the cytotoxicity of MC-LR in recent years was collected and summarized. It was found that MC-LR can induce a series of cytotoxic effects, including decreased cell viability, induced autophagy, apoptosis and necrosis, altered cell cycle, altered cell morphology, abnormal cell migration and invasion as well as leading to genetic damage. The above cytotoxic effects were related to the damage of various ultrastructure and functions such as cell membranes and mitochondria. Furthermore, MC-LR can disrupt cell ultrastructure and function by inducing oxidative stress and inhibiting protein phosphatase activity. In addition, the combined toxic effects of MC-LR and other environmental pollutants were investigated. This review explored the toxic targets of MC-LR at the subcellular level, which will provide new ideas for the prevention and treatment of multi-organ toxicity caused by MC-LR.
Collapse
Affiliation(s)
- Kangfeng Ge
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Xingde Du
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Haohao Liu
- Department of Public Health, First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450001, China
| | - Ruiyang Meng
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Chunrui Wu
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Zongxin Zhang
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Xiao Liang
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Jun Yang
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China
| | - Huizhen Zhang
- College of Public Health, Zhengzhou University, Zhengzhou, 450001, China.
| |
Collapse
|
3
|
Cao L, Shao N, Du J, Zhu H, Gao J, Li Q, Sun Y, Hu J, Yin G, Xu G. Involvement of reactive oxygen species (ROS) in the hepatopancreatic cytotoxicity, oxidative stress, and apoptosis induced by microcystin-LR in Eriocheir sinensis. Comp Biochem Physiol C Toxicol Pharmacol 2024; 276:109801. [PMID: 37996048 DOI: 10.1016/j.cbpc.2023.109801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/24/2023] [Accepted: 11/20/2023] [Indexed: 11/25/2023]
Abstract
There is limited knowledge about the toxicity of Microcystin-LR (MC-LR) in crustaceans, despite its high toxicity to aquatic organisms. This research aimed to explore the effects of MC-LR on cytotoxicity, oxidative stress, and apoptosis in the hepatopancreas of Eriocheir sinensis, as well as elucidate the involvement of reactive oxygen species (ROS) and potential mechanisms of toxicity. In vivo and in vitro exposures of crabs to MC-LR and N-acetylcysteine (NAC) were performed, followed by assessments of cell morphology, viability, tissue pathology, biochemical indicators, gene expression, and hepatopancreatic transcriptome. Results revealed that MC-LR facilitated the entry of the MC-LR transporter oatp3a into hepatopancreatic cells, leading to upregulated expression of phase I detoxification enzyme genes (cyp4c, cyp2e1, and cyp3) and downregulated the phase II enzyme genes (gst1, gpx, gsr2, gclc, and nqo1), resulting in increased ROS levels and cytotoxic effects. MC-LR exhibited cytotoxicity, reducing cell viability and inducing abnormal nuclear morphology with a 48 h-IC50 value of approximately 120 μm. MC-LR exposure caused biochemical changes indicative of oxidative stress damage and evident hepatopancreatic lesions. Additionally, MC-LR exposure regulated the levels of bax and bcl-2 expression, activating caspase 3 and 6 to induce cell apoptosis. Intervention with NAC attenuated MC-LR-induced ROS production and associated toxic effects. Transcriptome analysis revealed enrichment of differentially expressed genes in pathways related to cytochrome P450-mediated xenobiotic metabolism and the FoxO signaling pathway. These findings shed light on the potential mechanisms underlying MC-LR toxicity and provide valuable references for further research and conservation efforts regarding the health of aquatic animals.
Collapse
Affiliation(s)
- Liping Cao
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; International Joint Research Laboratory for Fish Immunopharmacology, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Nailin Shao
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Jinliang Du
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China; Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; International Joint Research Laboratory for Fish Immunopharmacology, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Haojun Zhu
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Jiancao Gao
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Quanjie Li
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yi Sun
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Jiawen Hu
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Guojun Yin
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; International Joint Research Laboratory for Fish Immunopharmacology, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Gangchun Xu
- Key Laboratory of Integrated Rice-Fish Farming Ecology, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
| |
Collapse
|
4
|
Li T, Fan X, Cai M, Jiang Y, Wang Y, He P, Ni J, Mo A, Peng C, Liu J. Advances in investigating microcystin-induced liver toxicity and underlying mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:167167. [PMID: 37730048 DOI: 10.1016/j.scitotenv.2023.167167] [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: 07/02/2023] [Revised: 08/27/2023] [Accepted: 09/15/2023] [Indexed: 09/22/2023]
Abstract
Microcystins (MCs) are a class of biologically active cyclic heptapeptide pollutants produced by the freshwater alga Microcystis aeruginosa. With increased environmental pollution, MCs have become a popular research topic. In recent years, the hepatotoxicity of MCs and associated effects and mechanisms have been studied extensively. Current epidemiological data indicate that long-term human exposure to MCs can lead to severe liver toxicity, acute toxicity, and death. In addition, current toxicological studies on the liver, a vital target organ of MCs, indicate that MC contamination is associated with the development of liver cancer, nonalcoholic fatty liver, and liver fibrosis. MCs produce hepatotoxicity that affects the metabolic homeostasis of the liver, induces apoptosis, and acts as a pro-cancer factor, leading to liver lesions. MCs mainly mediate the activation of signaling pathways, such as the ERK/JNK/p38 MAPK and IL-6-STAT3 pathways, which leads to oxidative damage and even carcinogenesis. Moreover, MCs can act synergistically with other pollutants to produce combined toxicity. However, few systematic reviews have been performed on these new findings. This review systematically summarizes the toxic effects and mechanisms of MCs on the liver and discusses the combined liver toxicity effects of MCs and other pollutants to provide reference for subsequent research. The toxicity of different MC isomers deserves further study. The detection methods and limit standards of MCs in agricultural and aquatic products will represent important research directions in the future. Standard protocols for fish sampling during harmful algal blooms or to evaluate the degree of MC toxicity in nature are lacking. In future, bioinformatics can be applied to offer insights into MC toxicology research and potential drug development for MC poisoning. Further research is essential to understand the molecular mechanisms of liver function damage in combined-exposure toxicology studies to establish treatment for MC-induced liver damage.
Collapse
Affiliation(s)
- Tong Li
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Xinting Fan
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Meihan Cai
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Yuanyuan Jiang
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Yaqi Wang
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Peishuang He
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Juan Ni
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Aili Mo
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Cuiying Peng
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China
| | - Jun Liu
- Department of Cell Biology and Genetics, Institute of Cytology and Genetics, School of Basic Medical Sciences, Hengyang Medical School, Key Laboratory of Hengyang City on Biological Toxicology and Ecological Restoration, Key Laboratory of Hengyang City on Ecological Impedance Technology of Heavy Metal Pollution in Cultivated Soil of Nonferrous Metal Mining Area, Key Laboratory of Ecological Environment and Critical Human Diseases Prevention of Hunan Province Department of Education, University of South China, Hengyang, Hunan 421001, China; School of Public Health, Hengyang Medical School, Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, University of South China, Hengyang, Hunan 421001, China.
| |
Collapse
|
5
|
Zhu L, Cao P, Yang S, Lin F, Wang J. Prolonged exposure to environmental levels of microcystin-LR triggers ferroptosis in brain via the activation of Erk/MAPK signaling pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 267:115651. [PMID: 37913581 DOI: 10.1016/j.ecoenv.2023.115651] [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: 07/25/2023] [Revised: 10/16/2023] [Accepted: 10/27/2023] [Indexed: 11/03/2023]
Abstract
While existing research has illuminated the environmental dangers and neurotoxic effects of MC-LR exposure, the molecular underpinnings of brain damage from environmentally-relevant MC-LR exposure remain elusive. Employing a comprehensive approach involving RNA sequencing, histopathological examination, and biochemical analyses, we discovered genes differentially expressed and enriched in the ferroptosis pathway. This finding was associated with mitochondrial structural impairment and downregulation of Gpx4 and Slc7a11 in mice brains subjected to low-dose MC-LR over 180 days. Mirroring these findings, we noted reduced cell viability and GSH/GSSH ratio, along with an increased ROS level, in HT-22, BV-2, and bEnd.3 cells following MC-LR exposure. Intriguingly, MC-LR also amplified phospho-Erk levels in both in vivo and in vitro settings, and the effects were mitigated by treatment with PD98059, an Erk inhibitor. Taken together, our findings implicate the activation of the Erk/MAPK signaling pathway in MC-LR-induced ferroptosis, shedding valuable light on the neurotoxic mechanisms of MC-LR. These insights could guide future strategies to prevent MC-induced neurodegenerative diseases.
Collapse
Affiliation(s)
- Lingyun Zhu
- Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Pingping Cao
- Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Suisui Yang
- Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Fan Lin
- Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, China.
| | - Jing Wang
- Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, Jiangsu, China.
| |
Collapse
|
6
|
Hu Z, Meng G, Zhang L, Zhang M, Cui H, Tang H. Protective effect of Huanglianjiedu Decoction on microcystin-LR induced nerve injury. Comp Biochem Physiol C Toxicol Pharmacol 2023; 272:109698. [PMID: 37442312 DOI: 10.1016/j.cbpc.2023.109698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 06/26/2023] [Accepted: 07/09/2023] [Indexed: 07/15/2023]
Abstract
Microcystin-LR (MC-LR) presented in eutrophic water has been identified as having the capacity to induce damage to the mammalian nervous system by crossing the blood-brain barrier through organic anion transporting polypeptides. However, the lack of effective preventive and protective strategies remains a concern. Huanglianjiedu Decoction (HLJD), a classical Chinese traditional formula originating from the Tang Dynasty and comprising Rhizoma Coptidis, Radix Scutellariae, Cortex Phellodendri, and Fructus Gardeniae, has exhibited neuroprotective effects attributed to its antioxidant properties. In this study, we investigated the potential of HLJD in counteracting the neurotoxic effects induced by MC-LR. Our findings revealed that MC-LR dose-dependently inhibited the activity of the PP2A enzyme in PC 12 cells and significantly elevated the phosphorylation levels of JNK, ERK1/2, and p38. Moreover, MC-LR administration resulted in synaptic damage in mouse neurons, hyperphosphorylation of the microtubule-related protein Tau, cognitive impairment, and deficits in learning and memory in C57BL/6J mice. Notably, HLJD effectively reversed the cytotoxicity caused by MC-LR in PC 12 cells, and attenuated MC-LR-induced neuronal damage while improving learning ability in mice. These results highlight the potential of HLJD as a promising protective strategy against MC-LR-induced neurological injury.
Collapse
Affiliation(s)
- Zhengqiang Hu
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Guanmin Meng
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada; Department of Clinical Laboratory, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang 310013, China
| | - Lejun Zhang
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Meng Zhang
- Department of Clinical Laboratory, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang 310013, China
| | - Huashun Cui
- Department of Acupuncture and Moxibustion, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 200021, China.
| | - Huifang Tang
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
7
|
Yao X, Liu Y, Yang Y, Li Y, Hu N, Song F, Yang F. Microcystin-LR-Exposure-Induced Kidney Damage by Inhibiting MKK6-Mediated Mitophagy in Mice. Toxins (Basel) 2023; 15:404. [PMID: 37368704 DOI: 10.3390/toxins15060404] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 06/29/2023] Open
Abstract
Previous studies have reported that microcystin-LR (MC-LR) levels are highly correlated with abnormal renal function indicators, suggesting that MC-LR is an independent risk factor for kidney damage. However, the evidence for the exact regulation mechanism of MC-LR on kidney damage is still limited, and further in-depth exploration is needed. In addition, the mitochondria-related mechanism of MC-LR leading to kidney damage has not been elucidated. To this end, the present study aimed to further explore the mechanism of mitophagy related to kidney damage induced by MC-LR through in vitro and in vivo experiments. Male C57BL/6 mice were fed with a standard rodent pellet and exposed daily to MC-LR (20 μg/kg·bw) via intraperitoneal injections for 7 days. Moreover, HEK 293 cells were treated with MC-LR (20 μM) for 24 h. The histopathological results exhibited kidney damage after MC-LR exposure, characterized by structurally damaged nephrotomies, with inflammatory cell infiltration. Similarly, a significant increase in renal interstitial fibrosis was observed in the kidneys of MC-LR-treated mice compared with those of the control group (CT) mice. MC-LR exposure caused impaired kidney function, with markedly increased blood urea nitrogen (BUN), creatinine (Cr), and uric acid (UA) levels in mice. Ultrastructural analysis exhibited obviously swollen, broken, and disappearing mitochondrial crests, and partial mitochondrial vacuoles in the MC-LR-treated HEK 293 cells. The Western blotting results demonstrated that exposure to MC-LR significantly increased the protein expressions of MKK6, p-p38, and p62, while the expression of mitophagy-related proteins was significantly inhibited in the kidneys of mice and HEK293 cells, including parkin, TOM20, and LC3-II, indicating the inhibition of mitophagy. Therefore, our data suggest that the inhibition of MKK6-mediated mitophagy might be the toxicological mechanism of kidney toxicity in mice with acute exposure to MC-LR.
Collapse
Affiliation(s)
- Xueqiong Yao
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Ying Liu
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Yue Yang
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Department of Social Medicine and Health Management, Xiangya School of Public Health, Central South University, Changsha 410017, China
| | - Yafang Li
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Na Hu
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Fengmei Song
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Fei Yang
- Department of Epidemiology and Health Statistics, The Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Basic Medicine, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Department of Social Medicine and Health Management, Xiangya School of Public Health, Central South University, Changsha 410017, China
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210000, China
| |
Collapse
|
8
|
Nugumanova G, Ponomarev ED, Askarova S, Fasler-Kan E, Barteneva NS. Freshwater Cyanobacterial Toxins, Cyanopeptides and Neurodegenerative Diseases. Toxins (Basel) 2023; 15:toxins15030233. [PMID: 36977124 PMCID: PMC10057253 DOI: 10.3390/toxins15030233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/13/2023] [Accepted: 03/19/2023] [Indexed: 03/30/2023] Open
Abstract
Cyanobacteria produce a wide range of structurally diverse cyanotoxins and bioactive cyanopeptides in freshwater, marine, and terrestrial ecosystems. The health significance of these metabolites, which include genotoxic- and neurotoxic agents, is confirmed by continued associations between the occurrence of animal and human acute toxic events and, in the long term, by associations between cyanobacteria and neurodegenerative diseases. Major mechanisms related to the neurotoxicity of cyanobacteria compounds include (1) blocking of key proteins and channels; (2) inhibition of essential enzymes in mammalian cells such as protein phosphatases and phosphoprotein phosphatases as well as new molecular targets such as toll-like receptors 4 and 8. One of the widely discussed implicated mechanisms includes a misincorporation of cyanobacterial non-proteogenic amino acids. Recent research provides evidence that non-proteinogenic amino acid BMAA produced by cyanobacteria have multiple effects on translation process and bypasses the proof-reading ability of the aminoacyl-tRNA-synthetase. Aberrant proteins generated by non-canonical translation may be a factor in neuronal death and neurodegeneration. We hypothesize that the production of cyanopeptides and non-canonical amino acids is a more general mechanism, leading to mistranslation, affecting protein homeostasis, and targeting mitochondria in eukaryotic cells. It can be evolutionarily ancient and initially developed to control phytoplankton communities during algal blooms. Outcompeting gut symbiotic microorganisms may lead to dysbiosis, increased gut permeability, a shift in blood-brain-barrier functionality, and eventually, mitochondrial dysfunction in high-energy demanding neurons. A better understanding of the interaction between cyanopeptides metabolism and the nervous system will be crucial to target or to prevent neurodegenerative diseases.
Collapse
Affiliation(s)
- Galina Nugumanova
- Department of Biology, School of Sciences and Humanities, Nazarbayev University, Astana 010000, Kazakhstan
| | - Eugene D Ponomarev
- Department of Biology, School of Sciences and Humanities, Nazarbayev University, Astana 010000, Kazakhstan
| | - Sholpan Askarova
- Center for Life Sciences, National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan
| | - Elizaveta Fasler-Kan
- Department of Pediatric Surgery, Children's Hospital, Inselspital Bern, University of Bern, 3010 Bern, Switzerland
| | - Natasha S Barteneva
- Department of Biology, School of Sciences and Humanities, Nazarbayev University, Astana 010000, Kazakhstan
- The Environment & Resource Efficiency Cluster (EREC), Nazarbayev University, Astana 010000, Kazakhstan
| |
Collapse
|
9
|
Falfushynska H, Kasianchuk N, Siemens E, Henao E, Rzymski P. A Review of Common Cyanotoxins and Their Effects on Fish. TOXICS 2023; 11:toxics11020118. [PMID: 36850993 PMCID: PMC9961407 DOI: 10.3390/toxics11020118] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/23/2023] [Accepted: 01/23/2023] [Indexed: 05/31/2023]
Abstract
Global warming and human-induced eutrophication drive the occurrence of various cyanotoxins in aquatic environments. These metabolites reveal diversified mechanisms of action, encompassing cyto-, neuro-, hepato-, nephro-, and neurotoxicity, and pose a threat to aquatic biota and human health. In the present paper, we review data on the occurrence of the most studied cyanotoxins, microcystins, nodularins, cylindrospermopsin, anatoxins, and saxitoxins, in the aquatic environment, as well as their potential bioaccumulation and toxicity in fish. Microcystins are the most studied among all known cyanotoxins, although other toxic cyanobacterial metabolites are also commonly identified in aquatic environments and can reveal high toxicity in fish. Except for primary toxicity signs, cyanotoxins adversely affect the antioxidant system and anti-/pro-oxidant balance. Cyanotoxins also negatively impact the mitochondrial and endoplasmic reticulum by increasing intracellular reactive oxygen species. Furthermore, fish exposed to microcystins and cylindrospermopsin exhibit various immunomodulatory, inflammatory, and endocrine responses. Even though cyanotoxins exert a complex pressure on fish, numerous aspects are yet to be the subject of in-depth investigation. Metabolites other than microcystins should be studied more thoroughly to understand the long-term effects in fish and provide a robust background for monitoring and management actions.
Collapse
Affiliation(s)
- Halina Falfushynska
- Department of Marine Biology, Institute for Biological Sciences, University of Rostock, 18059 Rostock, Germany
- Faculty of Electrical, Mechanical and Industrial Engineering, Anhalt University for Applied Sciences, 06366 Köthen, Germany
| | - Nadiia Kasianchuk
- Faculty of Biology, Adam Mickiewicz University, 61712 Poznan, Poland
| | - Eduard Siemens
- Faculty of Electrical, Mechanical and Industrial Engineering, Anhalt University for Applied Sciences, 06366 Köthen, Germany
| | - Eliana Henao
- Research Group Integrated Management of Ecosystems and Biodiversity XIUÂ, School of Biological Sciences, Universidad Pedagógica y Tecnológica de Colombia, Tunja 150003, Colombia
| | - Piotr Rzymski
- Department of Environmental Medicine, Poznan University of Medical Sciences, 61701 Poznan, Poland
- Integrated Science Association (ISA), Universal Scientific Education and Research Network (USERN), 61701 Poznań, Poland
| |
Collapse
|
10
|
Towards a Better Quantification of Cyanotoxins in Fruits and Vegetables: Validation and Application of an UHPLC-MS/MS-Based Method on Belgian Products. SEPARATIONS 2022. [DOI: 10.3390/separations9100319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Vegetables and fruits can potentially accumulate cyanotoxins after water contaminated with cyanobacteria is used for irrigation. We developed and validated an analytical method to quantify eight microcystin congeners (MCs) and nodularin (NOD) using ultra high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) in three different matrices. Strawberries, carrots and lettuce are selected as model matrices to represent the fruits/berries, leafy and root vegetables, sequentially. The validation of a UHPLC-MS/MS method in the strawberry matrix is novel. Matrix effects are observed in all three matrices. Our methodology uses matrix-matched calibration curves to compensate for the matrix effect. The implementation of our method on 103 samples, containing nine different sorts of fruits and vegetables from the Belgian market, showed no presence of MCs or NOD. However, the recoveries of our quality controls showed the effectiveness of our method, illustrating that the use of this method in future research or monitoring as well as in official food controls in fruit and vegetable matrices is valid.
Collapse
|
11
|
Turco L, Santori N, Buratti FM, Dorne JLCM, Testai E. Congeners-Specific Intestinal Absorption Of Microcystins In An In Vitro 3D Human Intestinal Epithelium: The Role Of Influx/Efflux Transporters. FRONTIERS IN TOXICOLOGY 2022; 4:883063. [PMID: 35990858 PMCID: PMC9388863 DOI: 10.3389/ftox.2022.883063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 03/28/2022] [Indexed: 11/18/2022] Open
Abstract
Microcystins constitute a group of over 200 variants and are increasingly considered as emerging toxins in food and feed safety, particularly with regards to sea-food and fish consumption. Toxicity of MCs is congener-specific, being characterised by different acute potencies, likely related to the differential activity of metabolic enzymes and transporters proteins involved in their cellular uptake. However, the active transport of MCs across intestinal membranes has not been fully elucidated. Our results, obtained using a fit for purpose 3D human reconstructed intestinal epithelium, provide new information on the complex mechanisms involved in the absorption of 5 MC variants’: it is indeed characterised by the equilibrium between uptake and extrusion, since the selected congeners are substrates of both influx and efflux proteins. In the range of tested nominal concentrations (10–40 µM) fully representative of relevant exposure scenarios, none of the active tested transporters were saturated. The comparison of permeability (Papp) values of MCs variants highlighted a dose independent relationship for MC-LR, -YR and -RR (Papp x 10–7 ranged from 2.95 to 3.54 cm/s), whereas -LW and–LF showed a dose dependent increase in permeability reaching Papp values which were similar to the other congeners at 40 µM. MC-RR, -LR, -YR show absorption values around 5% of the administered dose. Due to their lipophilicity, MC-LW and -LF were also detected within the cellular compartment. The intestinal uptake was only partially attributable to OATPs, suggesting the involvement of additional transporters. Regarding the efflux proteins, MCs are not P-gp substrates whereas MRP2 and to a lesser extent Breast cancer resistance protein are active in their extrusion. Despite the presence of GST proteins, as an indication of metabolic competence, in the intestinal tissue, MC-conjugates were never detected in our experimental settings.
Collapse
Affiliation(s)
- Laura Turco
- Istituto Superiore Di Sanità, Environment & Health Dept, Rome, Italy
- *Correspondence: Laura Turco,
| | - Nicoletta Santori
- Istituto Superiore Di Sanità, Environment & Health Dept, Rome, Italy
| | - Franca M. Buratti
- Istituto Superiore Di Sanità, Environment & Health Dept, Rome, Italy
| | | | - Emanuela Testai
- Istituto Superiore Di Sanità, Environment & Health Dept, Rome, Italy
| |
Collapse
|
12
|
Shartau RB, Snyman HN, Turcotte L, McCarron P, Bradshaw JC, Johnson SC. Acute microcystin exposure induces reversible histopathological changes in Chinook Salmon (Oncorhynchus tshawytscha) and Atlantic Salmon (Salmo salar). JOURNAL OF FISH DISEASES 2022; 45:729-742. [PMID: 35235682 DOI: 10.1111/jfd.13599] [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: 12/27/2021] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Atlantic Salmon (Salmo salar) and Chinook Salmon (Oncorhynchus tshawytscha) develop a severe liver disease called net-pen liver disease (NPLD), which is characterized by hepatic lesions that include megalocytosis and loss of gross liver structure. Based on studies where salmonids have been exposed to microcystin (MC) via intraperitoneal injection, NPLD is believed to be caused by MC exposure, a hepatotoxin produced by cyanobacteria. Despite the link between MC and NPLD, it remains uncertain if environmentally relevant MC exposure is responsible for NPLD. To determine if we could produce histopathology consistent with NPLD, we compared the response of Atlantic and Chinook Salmon sub-lethal MC exposure. Salmon were orally gavaged with saline or MC containing algal paste and sampled over 2 weeks post-exposure. Liver lesions appeared by 6 h but were resolved 2-weeks post-exposure; histopathological changes observed in other tissues were not as widespread, nor was their severity as great as those in the liver. There was no evidence for NPLD due to the absence of hepatic megalocytosis. These results indicate that the development of NPLD is not due to acute MC exposure but may be associated with higher MC concentration occurring in food, long-term exposure through drinking of contaminated seawater and/or interactions with other marine toxins.
Collapse
Affiliation(s)
- Ryan B Shartau
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia, Canada
- Department of Biology, The University of Texas at Tyler, Tyler, Texas, USA
| | - Heindrich N Snyman
- Animal Health Laboratory, University of Guelph, Kemptville, Ontario, Canada
| | - Lenora Turcotte
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia, Canada
| | - Pearse McCarron
- Biotoxin Metrology, National Research Council Canada, Halifax, Nova Scotia, Canada
| | - Julia C Bradshaw
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia, Canada
| | - Stewart C Johnson
- Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia, Canada
| |
Collapse
|
13
|
Acuña-Alonso C, Álvarez X, Valero E, Pacheco FAL. Modelling of threats that affect Cyano-HABs in an eutrophicated reservoir: First phase towards water security and environmental governance in watersheds. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 809:152155. [PMID: 34890658 DOI: 10.1016/j.scitotenv.2021.152155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 06/13/2023]
Abstract
Cyano-HABs are proliferating around the world due to anthropogenic nutrient enrichment of freshwater bodies. This study seeks to obtain a holistic vision over the various threats that affect the Cyano-HABs of Umia basin and especially of A Baxe reservoir (Galicia, NW Spain), through the method of Partial least squares path modelling (PLS-PM). The A Baxe reservoirs is a fundamental source of drinking water supply to surrounding dwellings. This study identifies and quantify the variables that increase contaminant concentration and decrease ecological integrity, as well as how this scenario evolved over various hydrologic years. In this regard, the PLS-PM equations will be robust and powerful tools to predict changes in eutrophication and ecological integrity, as response to measures implemented in the basin that can improve water quality. The dependent latent variables are "Eutrophication" (chlorophyl-a, Microcystis sp.) and "Ecological Integrity" (METI Bioindicator). The independent latent variables are "SWP", which represents surface water parameters (phosphorus, nitrogen and pH) and "Climatic Conditions" (temperature, precipitation). The PLS-PM results revealed that 51.0% of "Eutrophication" is predicted by the independent variables. The connections between latent variables are quantified through path coefficients (β). The "SWP" contributes by increasing "Eutrophication" (β = 0.235), the same occurring with the "Climatic Conditions" (β = -0.672). The variables "Eutrophication" (β = -0.217) and "SWP" (β = -0.483) lower the "Ecological Integrity". On the other hand, different trophic scenarios, adapted to the temperature increase predicted for the study area, were tested, and it was found that ecological integrity would improve by 46% if the oligotrophic state were reached. Therefore, it is recommended to prevent pollution by means of water control and governance plans, as well as corrective and preventive measures, which guarantee the water security of the river basins. Despite the complex mathematics behind the PLS-PM models, their user-friendly development and application through interactive graphical interfaces make them easily transposable to other eutrophic reservoirs, widening the readership of these studies focused on multiple-geosphere assessment of environmental impacts.
Collapse
Affiliation(s)
- Carolina Acuña-Alonso
- University of Vigo, Agroforestry Group, School of Forestry Engineering, 36005 Pontevedra, Spain.
| | - Xana Álvarez
- University of Vigo, Agroforestry Group, School of Forestry Engineering, 36005 Pontevedra, Spain.
| | - Enrique Valero
- University of Vigo, Agroforestry Group, School of Forestry Engineering, 36005 Pontevedra, Spain.
| | - Fernando António Leal Pacheco
- Center of Chemistry of Vila Real, University of Trás-os-Montes e Alto Douro, Ap. 1013, 5001-801 Vila Real, Portugal.
| |
Collapse
|
14
|
A Summer of Cyanobacterial Blooms in Belgian Waterbodies: Microcystin Quantification and Molecular Characterizations. Toxins (Basel) 2022; 14:toxins14010061. [PMID: 35051038 PMCID: PMC8780180 DOI: 10.3390/toxins14010061] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/08/2022] [Accepted: 01/12/2022] [Indexed: 12/04/2022] Open
Abstract
In the context of increasing occurrences of toxic cyanobacterial blooms worldwide, their monitoring in Belgium is currently performed by regional environmental agencies (in two of three regions) using different protocols and is restricted to some selected recreational ponds and lakes. Therefore, a global assessment based on the comparison of existing datasets is not possible. For this study, 79 water samples from a monitoring of five lakes in Wallonia and occasional blooms in Flanders and Brussels, including a canal, were analyzed. A Liquid Chromatography with tandem mass spectrometry (LC-MS/MS) method allowed to detect and quantify eight microcystin congeners. The mcyE gene was detected using PCR, while dominant cyanobacterial species were identified using 16S RNA amplification and direct sequencing. The cyanobacterial diversity for two water samples was characterized with amplicon sequencing. Microcystins were detected above limit of quantification (LOQ) in 68 water samples, and the World Health Organization (WHO) recommended guideline value for microcystins in recreational water (24 µg L−1) was surpassed in 18 samples. The microcystin concentrations ranged from 0.11 µg L−1 to 2798.81 µg L−1 total microcystin. For 45 samples, the dominance of the genera Microcystis sp., Dolichospermum sp., Aphanizomenon sp., Cyanobium/Synechococcus sp., Planktothrix sp., Romeria sp., Cyanodictyon sp., and Phormidium sp. was shown. Moreover, the mcyE gene was detected in 75.71% of all the water samples.
Collapse
|
15
|
Jaeger-Honz S, Nitschke J, Altaner S, Klein K, Dietrich DR, Schreiber F. Investigation of microcystin conformation and binding towards PPP1 by molecular dynamics simulation. Chem Biol Interact 2022; 351:109766. [PMID: 34861245 DOI: 10.1016/j.cbi.2021.109766] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/18/2021] [Accepted: 11/19/2021] [Indexed: 11/30/2022]
Abstract
Microcystins (MC) are a group of structurally similar cyanotoxins with currently 279 described structural variants. Human exposure is frequent by consumption of contaminated water, food or food supplements. MC can result in serious intoxications, commensurate with ensuing pathology in various organs or in rare cases even mortality. The current WHO risk assessment primarily considers MC-LR, while all other structural variants are treated as equivalent to MC-LR, despite that current data strongly suggest that MC-LR is not the most toxic MC, and toxicity can be very different for MC congeners. To investigate and analyse binding and conformation of different MC congeners, we applied for the first time Molecular Dynamics (MD) simulation to four MC congeners (MC-LR, MC-LF, [Enantio-Adda5]MC-LF, [β-D-Asp3,Dhb7]MC-RR). We could show that ser/thr protein phosphatase 1 is stable in all MD simulations and that MC-LR backbone adopts to a second conformation in solvent MD simulation, which was previously unknown. We could also show that MC congeners can adopt to different backbone conformation when simulated in solvent or in complex with ser/thr protein phosphatase 1 and differ in their binding behaviour. Our findings suggest that MD Simulation of different MC congeners aid in understanding structural differences and binding of this group of structurally similar cyanotoxins.
Collapse
Affiliation(s)
- Sabrina Jaeger-Honz
- Department of Computer and Information Science, University of Konstanz, Germany
| | - Jahn Nitschke
- Department of Biology, University of Konstanz, Germany
| | | | - Karsten Klein
- Department of Computer and Information Science, University of Konstanz, Germany
| | | | - Falk Schreiber
- Department of Computer and Information Science, University of Konstanz, Germany; Faculty of Information Technology, Monash University, Australia.
| |
Collapse
|
16
|
Pestana CJ, Moura DS, Capelo-Neto J, Edwards C, Dreisbach D, Spengler B, Lawton LA. Potentially Poisonous Plastic Particles: Microplastics as a Vector for Cyanobacterial Toxins Microcystin-LR and Microcystin-LF. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15940-15949. [PMID: 34758624 DOI: 10.1021/acs.est.1c05796] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The potential of microplastics to act as a vector for micropollutants of natural or anthropogenic origin is of rising concern. Cyanobacterial toxins, including microcystins, are harmful to humans and wildlife. In this study, we demonstrate for the first time the potential of microplastics to act as vectors for two different microcystin analogues. A concentration of up to 28 times from water to plastic was observed for the combination of polystyrene and microcystin-LF achieving toxin concentrations on the plastic of 142 ± 7 μg g-1. Based on the experimental results, and assuming a worst-case scenario, potential toxin doses for daphnids are calculated based on published microplastic ingestion data. Progressing up through trophic levels, theoretically, the concentration of microcystins in organisms is discussed. The experimental results indicate that adsorption of microcystins onto microplastics is a multifactorial process, depending on the particle size, the variable amino acid composition of the microcystins, the type of plastic, and pH. Furthermore, the results of the current study stressed the limitations of exclusively investigating microcystin-LR (the most commonly studied microcystin congener) as a model compound representing a group of around 250 reported microcystin congeners.
Collapse
Affiliation(s)
- Carlos J Pestana
- School of Pharmacy and Life Sciences, Robert Gordon University, Sir Ian Wood Building, Garthdee Road, Aberdeen AB10 7GJ, U.K
| | - Diana S Moura
- School of Pharmacy and Life Sciences, Robert Gordon University, Sir Ian Wood Building, Garthdee Road, Aberdeen AB10 7GJ, U.K
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Avenida Humberto Monte, Pici Campus Block 713 (first floor), Fortaleza, Ceará 60440-593, Brazil
| | - José Capelo-Neto
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Avenida Humberto Monte, Pici Campus Block 713 (first floor), Fortaleza, Ceará 60440-593, Brazil
| | - Christine Edwards
- School of Pharmacy and Life Sciences, Robert Gordon University, Sir Ian Wood Building, Garthdee Road, Aberdeen AB10 7GJ, U.K
| | - Domenic Dreisbach
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, Giessen D-35392, Germany
| | - Bernhard Spengler
- Institute of Inorganic and Analytical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, Giessen D-35392, Germany
| | - Linda A Lawton
- School of Pharmacy and Life Sciences, Robert Gordon University, Sir Ian Wood Building, Garthdee Road, Aberdeen AB10 7GJ, U.K
| |
Collapse
|
17
|
Ma Y, Wang J, Xu D, Chen Y, Han X. Chronic MC-LR exposure promoted Aβ and p-tau accumulation via regulating Akt/GSK-3β signal pathway. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148732. [PMID: 34323745 DOI: 10.1016/j.scitotenv.2021.148732] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/10/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
It has been reported that microcystin-leucine-arginine (MC-LR) can enter into the brain and demonstrate neurotoxicity resulting in learning and memory deficits. While, there is still a lack of clear understanding of the related molecular mechanisms. In this study, we observed β-amyloid (Aβ) accumulation and tau hyperphosphorylation (p-tau) at sites of Ser396 and Thr205 in mouse hippocampus and cortex, Alzheimer's disease (AD) like changes, after chronic exposure to MC-LR at different concentrations (1, 7.5, 15 and 30 μg/L) for 180 days. The hallmarks of AD are characterized by senile plaques and neurofibrillary tangles (NFT), with associated loss of neurons, resulting in cognitive impairment and dementia. Similarly, the production of Aβ and tau hyperphosphorylation was also detected in HT-22 cells treated with MC-LR. In addition, MC-LR promoted increased expressions of BACE1 and PS1, but reduced mRNA expressions of ADAM family members both in vivo and in vitro, promoting the Aβ production. Moreover, we identified Akt/GSK-3β signal pathway mediated the Aβ and p-tau accumulation, bringing about Alzheimer's disease-like changes. Furthermore, microglial cells were activated in those mice exposed to MC-LR. Inflammatory cytokines were also found being activated to release in vitro. In conclusion, this study could provide a clue for MC-LR-induced neurotoxicity, which gave insights into the environmental risks of Alzheimer's disease.
Collapse
Affiliation(s)
- Yuhan Ma
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Jing Wang
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Dihui Xu
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China
| | - Yabing Chen
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China.
| | - Xiaodong Han
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China.
| |
Collapse
|
18
|
Banerjee S, Maity S, Guchhait R, Chatterjee A, Biswas C, Adhikari M, Pramanick K. Toxic effects of cyanotoxins in teleost fish: A comprehensive review. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2021; 240:105971. [PMID: 34560410 DOI: 10.1016/j.aquatox.2021.105971] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 09/03/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
The phenomenon of eutrophication leads to the global occurrence of algal blooms. Cyanotoxins as produced by many cyanobacterial species can lead to detrimental effects to the biome due to their stability and potential biomagnification along food webs. Therefore, understanding of the potential risks these toxins pose to the most susceptible organisms is an important prerequisite for ecological risks assessment of cyanobacteria blooms. Fishes are an important component of aquatic ecosystems that are prone to direct exposure to cyanotoxins. However, relatively few investigations have focused on measuring the toxic potentials of cyanotoxins in teleost fishes. This review comprehensively describes the major toxicological impacts (such as hepatotoxicity, neurotoxicity, immune toxicity, reproductive toxicity and cytogenotoxicity) of commonly occurring cyanotoxins in teleost fishes. The present work encompasses recent research progresses with special emphasis on the basic molecular mechanisms by which different cyanotoxins impose their toxicities in teleost fishes. The major research areas, which need to be focused on in future scientific investigations, have also been highlighted. Protein kinase inhibition, transcriptional dysregulation, disruption of redox homeostasis and the induction of apoptotic pathways appear to be the key drivers of the toxicological effects of cyanotoxins in fish. Analyses also showed that the impacts of cyanotoxins on specific reproductive processes are relatively less described in teleosts in comparison to mammalian systems. In fact, as compared to other toxicological effects of cyanotoxins, their reproductive toxicity (such as impacts on oocyte development, maturation and their hormonal regulation) is poorly understood in fish, and thus requires further studies. Furthermore, additonal studies characterizing the molecular mechanisms responsible for the cellular uptake of cyanotoxins need to be investigated.
Collapse
Affiliation(s)
- Sambuddha Banerjee
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India
| | - Sukhendu Maity
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India
| | - Rajkumar Guchhait
- P.G. Department of Zoology, Mahishadal Raj College, Garkamalpur, Purba Medinipur, India
| | - Ankit Chatterjee
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India
| | - Chayan Biswas
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India
| | - Madhuchhanda Adhikari
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India
| | - Kousik Pramanick
- Integrative Biology Research Unit, Department of Life Sciences, Presidency University, 86/1, College Street, Kolkata 700073, India.
| |
Collapse
|
19
|
Fournier C, Riehle E, Dietrich DR, Schleheck D. Is Toxin-Producing Planktothrix sp. an Emerging Species in Lake Constance? Toxins (Basel) 2021; 13:toxins13090666. [PMID: 34564670 PMCID: PMC8472890 DOI: 10.3390/toxins13090666] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 01/04/2023] Open
Abstract
Recurring blooms of filamentous, red-pigmented and toxin-producing cyanobacteria Planktothrix rubescens have been reported in numerous deep and stratified prealpine lakes, with the exception of Lake Constance. In a 2019 and 2020 Lake Constance field campaign, we collected samples from a distinct red-pigmented biomass maximum below the chlorophyll-a maximum, which was determined using fluorescence probe measurements at depths between 18 and 20 m. Here, we report the characterization of these deep water red pigment maxima (DRM) as cyanobacterial blooms. Using 16S rRNA gene-amplicon sequencing, we found evidence that the blooms were, indeed, contributed by Planktothrix spp., although phycoerythrin-rich Synechococcus taxa constituted most of the biomass (>96% relative read abundance) of the cyanobacterial DRM community. Through UPLC-MS/MS, we also detected toxic microcystins (MCs) in the DRM in the individual sampling days at concentrations of ≤1.5 ng/L. Subsequently, we reevaluated the fluorescence probe measurements collected over the past decade and found that, in the summer, DRM have been present in Lake Constance, at least since 2009. Our study highlights the need for a continuous monitoring program also targeting the cyanobacterial DRM in Lake Constance, and for future studies on the competition of the different cyanobacterial taxa. Future studies will address the potential community composition changes in response to the climate change driven physiochemical and biological parameters of the lake.
Collapse
Affiliation(s)
- Corentin Fournier
- Microbial Ecology and Limnic Microbiology, University of Konstanz, 78457 Konstanz, Germany;
| | - Eva Riehle
- Human and Environmental Toxicology, University of Konstanz, 78457 Konstanz, Germany;
| | - Daniel R. Dietrich
- Human and Environmental Toxicology, University of Konstanz, 78457 Konstanz, Germany;
- Correspondence: (D.R.D.); (D.S.)
| | - David Schleheck
- Microbial Ecology and Limnic Microbiology, University of Konstanz, 78457 Konstanz, Germany;
- Limnological Institute, University of Konstanz, 78457 Konstanz, Germany
- Correspondence: (D.R.D.); (D.S.)
| |
Collapse
|
20
|
Cyanotoxins and the Nervous System. Toxins (Basel) 2021; 13:toxins13090660. [PMID: 34564664 PMCID: PMC8472772 DOI: 10.3390/toxins13090660] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 08/31/2021] [Accepted: 09/09/2021] [Indexed: 11/16/2022] Open
Abstract
Cyanobacteria are capable of producing a wide range of bioactive compounds with many considered to be toxins. Although there are a number of toxicological outcomes with respect to cyanobacterial exposure, this review aims to examine those which affect the central nervous system (CNS) or have neurotoxicological properties. Such exposures can be acute or chronic, and we detail issues concerning CNS entry, detection and remediation. Exposure can occur through a variety of media but, increasingly, exposure through air via inhalation may have greater significance and requires further investigation. Even though cyanobacterial toxins have traditionally been classified based on their primary mode of toxicity, increasing evidence suggests that some also possess neurotoxic properties and include known cyanotoxins and unknown compounds. Furthermore, chronic long-term exposure to these compounds is increasingly being identified as adversely affecting human health.
Collapse
|
21
|
Mao Y, Zong Z, Dang Y, Yu L, Liu C, Wang J. Promotion effect of microcystin-LR on liver tumor progression in kras V12 transgenic zebrafish following acute or subacute exposure. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 224:112673. [PMID: 34438271 DOI: 10.1016/j.ecoenv.2021.112673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 07/27/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
Microcystin-LR (MC-LR) is widely distributed in the natural environment and causes hepatotoxicity. However, whether MC-LR promotes liver tumor progression remains controversial. krasV12 transgenic zebrafish were used as an inducible liver tumor model to evaluate the potential tumor-promoting effect of MC-LR. First, krasV12 transgenic larvae were exposed to 0, 0.1 and 1 mg/L MC-LR with 20 mg/L doxycycline (Dox) for 4 d. The gray values and histopathological examinations of the liver demonstrated that MC-LR aggravated liver tumor progression, which could be inhibited by the Protein arginine methyltransferase 5 (Prmt5) inhibitor compound 5 (CMP5). Second, 1-month-old juvenile transgenic zebrafish were exposed to 0, 20 mg/L Dox, 1 μg/L MC-LR, and 20 mg/L Dox with 0.1 or 1 μg/L MC-LR for 15 d to determine whether the exposure to environmental concentrations of MC-LR promoted hepatocellular carcinoma (HCC) progression. We found that environmental concentrations of MC-LR increased the hepatosomatic index (HSI) and gray value (intensity/area) and promoted HCC progression. The results indicate that environmental concentrations of MC-LR have the potential to promote liver tumor progression. Taken together, the present study demonstrates that MC-LR can promote tumor in krasV12 transgenic zebrafish and that the upregulation of prmt5 expression might contribute to MC-LR-mediated promotion of liver tumorigenesis.
Collapse
Affiliation(s)
- Yuchao Mao
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Zijing Zong
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Yao Dang
- 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.
| | - Liqin Yu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunsheng Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China
| | - Jianghua Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan 430070, China.
| |
Collapse
|
22
|
Mondal A, Saha P, Bose D, Chatterjee S, Seth RK, Xiao S, Porter DE, Brooks BW, Scott GI, Nagarkatti M, Nagarkatti P, Chatterjee S. Environmental Microcystin exposure in underlying NAFLD-induced exacerbation of neuroinflammation, blood-brain barrier dysfunction, and neurodegeneration are NLRP3 and S100B dependent. Toxicology 2021; 461:152901. [PMID: 34416350 DOI: 10.1016/j.tox.2021.152901] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/28/2021] [Accepted: 08/12/2021] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) has been shown to be associated with extrahepatic comorbidities including neuronal inflammation and Alzheimer's-like pathology. Environmental and genetic factors also act as a second hit to modulate severity and are expected to enhance the NAFLD-linked neuropathology. We hypothezied that environmental microcystin-LR (MC-LR), a toxin produced by harmful algal blooms of cyanobacteria, exacerbates the neuroinflammation and degeneration of neurons associated with NAFLD. Using a mouse model of NAFLD, exposed to MC-LR subsequent to the onset of fatty liver, we show that the cyanotoxin could significantly increase proinflammatory cytokine expression in the frontal cortex and cause increased expression of Lcn2 and HMGB1. The above effects were NLRP3 inflammasome activation-dependent since the use of NLRP3 knockout mice abrogated the increase in inflammation. NLRP3 was also responsible for decreased expression of the blood-brain barrier (BBB) tight junction proteins Occludin and Claudin 5 suggesting BBB dysfunction was parallel to neuroinflammation following microcystin exposure. An increased circulatory S100B release, a hallmark of astrocyte activation in MC-LR exposed NAFLD mice also confirmed BBB integrity loss, but the astrocyte activation observed in vivo was NLRP3 independent suggesting an important role of a secondary S100B mediated crosstalk. Mechanistically, conditioned medium from reactive astrocytes and parallel S100B incubation in neuronal cells caused increased inducible NOS, COX-2, and higher BAX/ Bcl2 protein expression suggesting oxidative stress-mediated neuronal cell apoptosis crucial for neurodegeneration. Taken together, MC-LR exacerbated neuronal NAFLD-linked comorbidities leading to cortical inflammation, BBB dysfunction, and neuronal apoptosis.
Collapse
Affiliation(s)
- Ayan Mondal
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA
| | - Punnag Saha
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA
| | - Dipro Bose
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA; Columbia VA Medical Center, Columbia, SC, 29209, USA
| | - Somdatta Chatterjee
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA
| | - Ratanesh K Seth
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA; Columbia VA Medical Center, Columbia, SC, 29209, USA
| | - Shuo Xiao
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy at Rutgers University, Piscataway, NJ, 08854, USA
| | - Dwayne E Porter
- NIEHS Center for Oceans and Human Health on Climate Change Interactions, Department of Environmental Health Sciences, University of South Carolina, 29208, USA
| | - Bryan W Brooks
- Department of Environmental Science, Baylor University, Waco, TX, 76798-7266, USA
| | - Geoff I Scott
- NIEHS Center for Oceans and Human Health on Climate Change Interactions, Department of Environmental Health Sciences, University of South Carolina, 29208, USA
| | - Mitzi Nagarkatti
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29209, USA
| | - Prakash Nagarkatti
- Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29209, USA
| | - Saurabh Chatterjee
- Environmental Health and Disease Laboratory, Arnold School of Public Health, University of South Carolina, Columbia, SC, 29208, USA; Columbia VA Medical Center, Columbia, SC, 29209, USA.
| |
Collapse
|
23
|
Wood SA, Puddick J, Hawes I, Steiner K, Dietrich DR, Hamilton DP. Variability in microcystin quotas during a Microcystis bloom in a eutrophic lake. PLoS One 2021; 16:e0254967. [PMID: 34288957 PMCID: PMC8294494 DOI: 10.1371/journal.pone.0254967] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 07/08/2021] [Indexed: 11/18/2022] Open
Abstract
Microcystis is a bloom-forming genus of cyanobacteria with some genotypes that produce highly toxic microcystin hepatotoxins. In waterbodies where biological and physical factors are relatively homogenous, toxin quotas (the average amount of toxin per cell), at a single point in time, are expected to be relatively constant. In this study we challenged this assumption by investigating the spatial distribution of microcystin quotas at a single point in time on two separate occasions in a lake with a major Microcystis bloom. Microcystis cell concentrations varied widely across the lake on both sampling occasions (730- and 137-fold) together with microcystin quotas (148- and 362-fold). Cell concentrations and microcystin quotas were strongly positively correlated (R2 = 0.89, P < 0.001, n = 28; R2 = 0.67, P < 0.001, n = 25). Analysis of Microcystis strains using high-throughput sequencing of the 16S-23S rRNA intergenic spacer region showed no relationship between microcystin quota and the relative abundance of specific sequences. Collectively, the results of this study indicate an association between microcystin production and cell density that magnifies the potential for bloom toxicity at elevated cell concentrations.
Collapse
Affiliation(s)
| | | | - Ian Hawes
- Department of Biological Sciences, University of Waikato, Hamilton, New Zealand
| | | | | | - David P. Hamilton
- Australian Rivers Institute, Griffith University, Brisbane, Australia
| |
Collapse
|
24
|
Zaidi H, Amrani A, Sedrati F, Maaref H, Leghrib F, Benamara M, Amara H, Wang Z, Nasri H. Histological and chemical damage induced by microcystin-LR and microcystin-RR on land snail Helix aspersa tissues after acute exposure. Comp Biochem Physiol C Toxicol Pharmacol 2021; 245:109031. [PMID: 33737222 DOI: 10.1016/j.cbpc.2021.109031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 02/09/2021] [Accepted: 03/06/2021] [Indexed: 11/17/2022]
Abstract
Microcystins (MCs) are the most common cyanotoxins with more than 200 variants. Among these cyanotoxins, microcystin-LR (MC-LR) and microcystin-RR (MC-RR) are the most studied congeners due to their high toxicity and frequent occurrence in surface waters. MC-LR has been detected in more than 75% of natural cyanobacteria bloom, along with other toxic and less toxic congeners. Accumulation of several microcystins variants (MC-LR and MC-RR) has been confirmed in aquatic snails exposed naturally or in the laboratory to toxic blooms. Thus, this paper aims to compare the biochemical and histological impact of both toxic variants (microcystin-LR and microcystin-RR) and their mixed form on a bioindicator, the land snail Helix aspersa. During experiments, snails were gavaged with a single acute dose (0.5 μg/g) of purified MC-LR, MC-RR, or mixed MC-LR + MC-RR (0.25 + 0.25 μg/g). After 96 h of exposure, effects on the hepatopancreas, kidney, intestine and lungs were assessed by histological observations and analysis of oxidative stress biomarkers. The results show that a small dose of MCs variants can increase the non-enzymatic antioxidant glutathione (GSH), inhibit glutathione-s-transferase (GST) level and trigger a defense system by activating glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD). Microcystin-RR causes serious anomalies in the hepatopancreas and kidney than Microcystin-LR. The organ most affected is the kidney. The damage caused by MC-LR + MC-RR is greater than that caused by single variants.
Collapse
Affiliation(s)
- H Zaidi
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria
| | - A Amrani
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria
| | - F Sedrati
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria
| | - H Maaref
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria; Central Pathology Laboratory, El Taref Hospital, El Tarf, Algeria
| | - F Leghrib
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria
| | - M Benamara
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria
| | - H Amara
- Central Pathology Laboratory, El Taref Hospital, El Tarf, Algeria
| | - Zhi Wang
- Key Laboratory for Environment and Disaster Monitoring and Evaluation, Hubei, Institute of Geodesy and Geophysics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China
| | - H Nasri
- Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria; Thematic Agency for Research in Health Sciences, Oran, Algeria.
| |
Collapse
|
25
|
Zeng H, Tan Y, Wang L, Xiang M, Zhou Z, Chen JA, Wang J, Zhang R, Tian Y, Luo J, Huang Y, Lv C, Shu W, Qiu Z. Association of serum microcystin levels with neurobehavior of school-age children in rural area of Southwest China: A cross-sectional study. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 212:111990. [PMID: 33524912 DOI: 10.1016/j.ecoenv.2021.111990] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
To investigate whether microcystin-LR (MC-LR) influences children's cognitive function and memory ability, we measured serum MC-LR and whole blood lead levels in 697 primary students, and collected their academic and neurobehavioral test scores. The median of serum MC-LR levels was 0.80 µg/L (the value below the limit of detection to 1.67 µg/L). The shapes of the associations of serum MC-LR levels (cut-point: 0.95 µg/L) with scores on academic achievements, digit symbol substitution test and long-term memory test were parabolic curves. Logistic regression analysis showed that MC-LR at concentrations of 0.80-0.95 µg/L was associated with the increased probability of higher achievements on academic achievements [odds ratio (OR) = 2.20, 95% confidence interval (CI): 1.28-3.79], and also with scores on digit symbol substitution test (OR = 1.73, 95% CI: 1.05-2.86), overall memory quotient (OR = 2.27, 95% CI: 1.21-4.26), long-term memory (OR = 1.85, 95% CI: 1.01-3.38) and short-term memory (OR = 2.13, 95% CI: 1.14-3.98) after adjustment for confounding factors. Antagonism of MC-LR and lead on long-term memory was observed (synergism index = 0.15, 95% CI: 0.03-0.74). In conclusion, serum MC-LR at concentrations of 0.80-0.95 µg/L was positively associated with higher scores on cognitive and neurobehavioral tests, and antagonism between MC-LR at concentrations of 0.80-1.67 µg/L and lead exposure was obviously observed on long-term memory in children. Concerning that MC-LR is a neurotoxin at high doses, our observation is interesting and need further investigation.
Collapse
Affiliation(s)
- Hui Zeng
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Yao Tan
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Lingqiao Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Menglong Xiang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Ziyuan Zhou
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Ji-An Chen
- Department of Health Education, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Jia Wang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Renping Zhang
- The Center for Disease Control and Prevention in Fuling District, Chongqing, China
| | - Yingqiao Tian
- The Center for Disease Control and Prevention in Fuling District, Chongqing, China
| | - Jiaohua Luo
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Yujing Huang
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Chen Lv
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China
| | - Weiqun Shu
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China.
| | - Zhiqun Qiu
- Department of Environmental Hygiene, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, China.
| |
Collapse
|
26
|
Henri J, Lanceleur R, Delmas JM, Fessard V, Huguet A. Permeability of the Cyanotoxin Microcystin-RR across a Caco-2 Cells Monolayer. Toxins (Basel) 2021; 13:toxins13030178. [PMID: 33673481 PMCID: PMC7997155 DOI: 10.3390/toxins13030178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 12/27/2022] Open
Abstract
Microcystins (MCs) are toxins produced by several cyanobacterial species found worldwide. While MCs have a common structure, the variation of two amino acids in their structure affects their toxicity. As toxicodynamics are very similar between the MC variants, their differential toxicity could rather be explained by toxicokinetic parameters. Microcystin-RR (MC-RR) is the second most abundant congener and induces toxicity through oral exposure. As intestinal permeability is a key parameter of oral toxicokinetics, the apparent permeability of MC-RR across a differentiated intestinal Caco-2 cell monolayer was investigated. We observed a rapid and large decrease of MC-RR levels in the donor compartment. However, irrespective of the loaded concentration and exposure time, the permeabilities were very low from apical to basolateral compartments (from 4 to 15 × 10−8 cm·s−1) and from basolateral to apical compartments (from 2 to 37 × 10−8 cm·s−1). Our results suggested that MC-RR would be poorly absorbed orally. As similar low permeability was reported for the most abundant congener microcystin-LR, and this variant presented a greater acute oral toxicity than MC-RR, we concluded that the intestinal permeability was probably not involved in the differential toxicity between them, in contrast to the hepatic uptake and metabolism.
Collapse
|
27
|
Xiao W, Zhong Q, Sun F, Wang W, Zhao Z, Gu K. Differences in Abnormal Water Metabolism between SD Rats and KM Mice Intoxicated by Microcystin-RR. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18041900. [PMID: 33669356 PMCID: PMC7920292 DOI: 10.3390/ijerph18041900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 01/17/2023]
Abstract
The effects of microcystin-RR (MC-RR) on water metabolism were studied on Sprague–Dawley (SD) rats and KunMing (KM) mice. In the single dose toxicity test, polydipsia, polyuria, hematuria and proteinuria were found in group of rats receiving a MC-RR dose of 574.7 μg/kg, and could be relieved by dexamethasone (DXM). Gradient damage was observed in kidney and liver in rats with gradient MC-RR doses of 574.7, 287.3, and 143.7 μg/kg. No significant water metabolic changes or kidney injuries were observed in mice treated with MC-RR doses of 210.0, 105.0, and 52.5 μg/kg. In the continuous exposure test, in which mice were administrated with 140.0, 70.0, and 35.0 μg/kg MC-RR for 28 days, mice in the 140.0 μg/kg group presented increasing polydipsia, polyuria, and liver damage. However, no anatomic or histological changes, including related serological and urinary indices, were found in the kidney. In summary, abnormal water metabolism can be induced by MC-RR in rats through kidney injury in single dose exposure; the kidney of SD rats is more sensitive to MC-RR than that of KM mouse; and polydipsia and polyuria in mice exposed to MC-RR for 28 days occurred but could not be attributed to kidney damage.
Collapse
|
28
|
Xu S, Yi X, Liu W, Zhang C, Massey IY, Yang F, Tian L. A Review of Nephrotoxicity of Microcystins. Toxins (Basel) 2020; 12:toxins12110693. [PMID: 33142924 PMCID: PMC7693154 DOI: 10.3390/toxins12110693] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/09/2020] [Accepted: 10/28/2020] [Indexed: 12/14/2022] Open
Abstract
Cyanobacterial blooms triggered by eutrophication and climate change have become a global public health issue. The toxic metabolites microcystins (MCs) generated by cyanobacteria can accumulate in food chain and contaminate water, thus posing a potential threat to human and animals health. Studies have suggested that aside liver, the kidney may be another target organ of MCs intoxication. Therefore, this review provides various evidences on the nephrotoxicity of MCs. The review concludes that nephrotoxicity of MCs may be related to inhibition of protein phosphatases and excessive production of reactive oxygen species, cytoskeleton disruption, endoplasmic reticulum stress, DNA damage and cell apoptosis. To protect human from MCs toxic consequences, this paper also puts forward some directions for further research.
Collapse
Affiliation(s)
- Shuaishuai Xu
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha 410078, Hunan, China; (S.X.); (W.L.); (C.Z.); (I.Y.M.)
| | - Xiping Yi
- School of Public Health, Xiangnan University, Chenzhou 423000, China;
- Chenzhou Center for Disease Control and Prevention, Chenzhou 423000, China
| | - Wenya Liu
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha 410078, Hunan, China; (S.X.); (W.L.); (C.Z.); (I.Y.M.)
| | - Chengcheng Zhang
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha 410078, Hunan, China; (S.X.); (W.L.); (C.Z.); (I.Y.M.)
| | - Isaac Yaw Massey
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha 410078, Hunan, China; (S.X.); (W.L.); (C.Z.); (I.Y.M.)
| | - Fei Yang
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Xiangya School of Public Health, Central South University, Changsha 410078, Hunan, China; (S.X.); (W.L.); (C.Z.); (I.Y.M.)
- Hunan Province Key Laboratory of Typical Environmental Pollution and Health Hazards, School of Public Health, University of South China, Hengyang 421001, China
- Correspondence: (F.Y.); (L.T.); Tel./Fax: +86-731-84805460 (F.Y.)
| | - Li Tian
- Department of Gastroenterology, Third Xiangya Hospital, Central South University, Changsha 410013, China
- Correspondence: (F.Y.); (L.T.); Tel./Fax: +86-731-84805460 (F.Y.)
| |
Collapse
|
29
|
Schreidah CM, Ratnayake K, Senarath K, Karunarathne A. Microcystins: Biogenesis, Toxicity, Analysis, and Control. Chem Res Toxicol 2020; 33:2225-2246. [PMID: 32614166 DOI: 10.1021/acs.chemrestox.0c00164] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Microcystins are cyclic peptide toxins formed by cyanobacteria. These toxins are recognized for their association with algal blooms, posing a significant threat to ecosystems and drinking water quality. Due to the growing environmental concerns they raise, a comprehensive review on microcystins' genesis, toxicity, and analytical methods for their quantitative determination is outlined. Genes, including the mcyABC cluster, regulate microcystin biogenesis. Bioanalytical experiments have identified key environmental factors, such as temperature and nitrogen availability, that promote microcystin production. Microcystin toxicity is explored based on its modulatory effects on protein phosphatases 1 and 2A in specific tissues and organs. Additionally, biochemical mechanisms of chelation, transportation, resultant oxidative stress, and tumor promotion abilities of microcystins are also discussed. Various analytical methods to separate, detect, and quantify microcystins, including the quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, nuclear magnetic resonance spectroscopy, and chromatographic platforms-linked tandem mass spectrometry (LC-MS) for unequivocal structural identification, are also reviewed. Since control of microcystins in water is of great necessity, both water treatment and mechanisms of abiotic transformation and microbial degradation are also discussed.
Collapse
Affiliation(s)
- Celine M Schreidah
- Vagelos College of Physicians and Surgeons, Columbia University, New York, New York 10032, United States
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
| | - Kasun Ratnayake
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
| | - Kanishka Senarath
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
- Department of Chemistry, University of Colombo, Colombo 00300, Sri Lanka
| | - Ajith Karunarathne
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, Ohio 43606, United States
| |
Collapse
|
30
|
Miller TR, Xiong A, Deeds JR, Stutts WL, Samdal IA, Løvberg KE, Miles CO. Microcystin Toxins at Potentially Hazardous Levels in Algal Dietary Supplements Revealed by a Combination of Bioassay, Immunoassay, and Mass Spectrometric Methods. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:8016-8025. [PMID: 32597644 DOI: 10.1021/acs.jafc.0c02024] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Microcystins (MCs) are hepatotoxic heptapeptides produced by cyanobacteria and are potent inhibitors of protein phosphatases in eukaryotic cells. Algae for dietary supplements are harvested from outdoor environments and can be contaminated with MCs. Monitoring of MCs in these products is necessary but is complicated by their structural diversity (>250 congeners). We used a combination of protein phosphatase inhibition assay (PPIA), ELISA, LC-MS/MS, and nontargeted LC-high-resolution MS (LC-HRMS) with thiol derivatization to characterize the total MCs in 18 algal dietary supplements. LC-MS/MS revealed that some products contained >40 times the maximum acceptable concentration (MAC) of 1 μg/g MCs, but ELISA and PPIA showed up to 50-60 times the MAC. LC-HRMS identified all congeners targeted by LC-MS/MS plus MC-(H4)YR contributing up to 18% of total MCs, along with numerous minor MCs. Recommended dosages of the products greater than the MAC would result in 2.6-75 times the tolerable daily intake, presenting a risk to consumers. This study confirms the need for monitoring these products and presents strategies to fully describe the total MC pool in environmental samples and algal products.
Collapse
Affiliation(s)
- Todd R Miller
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Ame Xiong
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, United States
| | - Jonathan R Deeds
- United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park, Maryland 20740-3835, United States
| | - Whitney L Stutts
- United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park, Maryland 20740-3835, United States
| | - Ingunn A Samdal
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway
| | - Kjersti E Løvberg
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway
| | - Christopher O Miles
- Biotoxin Metrology, National Research Council, 1411 Oxford Street, Halifax B3H 3Z1, NS, Canada
| |
Collapse
|
31
|
Álvarez SD, Kruk C, Martínez de la Escalera G, Montes MA, Segura AM, Piccini C. Morphology captures toxicity in Microcystis aeruginosa complex: Evidence from a wide environmental gradient ✰. HARMFUL ALGAE 2020; 97:101854. [PMID: 32732048 DOI: 10.1016/j.hal.2020.101854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/04/2020] [Accepted: 06/07/2020] [Indexed: 06/11/2023]
Abstract
Blooms of the Microcystis aeruginosa complex (MAC) consist of mixtures of toxin-producing and non-toxin-producing populations, but the environmental conditions that determine their relative abundance and shift are not clear. Morphological traits reflect the responses of MAC organisms to environmental changes, thus they could be useful to improve the predictability of the abundance of both toxic and nontoxic populations. In this work, the response of MAC toxic populations to environmental conditions and their relationship with morphology (size of organisms) were investigated in different water bodies (reservoir, river, and estuary) covering wide salinity (0-33) and temperature (10-36 °C) gradients. Sub-surface water samples were collected and divided into 4 size classes (mesh size 〈20 µm, 20-60 µm, 60-150 µm and〉 150 µm) and three toxicity proxies were assessed (mcyE gene and transcripts copy numbers and microcystin concentration) for each size-class. For all the size-classes, the logarithm of the number of mcyE gene copies per sample was proportional to the logarithm of the corresponding biovolume fraction, showing that MAC biovolume is a good indicator of toxicity potential. When toxicity was analyzed through mcyE transcript abundance and microcystin concentration, the largest size fraction (>150 µm) showed the highest toxicity values of both proxies. Nevertheless, mcyE transcription and toxin production per cell were higher in the colonies retained in the 60 to 150 µm size fractions, followed by single cells (<20 µm). At the reservoir, where environmental variability is low, the total abundance of mcyE gene copies was significantly explained by MAC biovolume, regardless of the environmental conditions. However, when data from the reservoir to the estuary were modeled, biovolume and temperature (with a minor contribution of salinity and wind intensity) were selected in the best models. According to these results, the size distribution of MAC biovolume appears as a good predictor of active toxin production, being the colonies in the 60-150 µm size fraction good indicators of higher toxicity. These results can be used to predict MAC toxicity based on the size structure of the community.
Collapse
Affiliation(s)
- Susana Deus Álvarez
- Departamento de Microbiología, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay
| | - Carla Kruk
- Ecología Funcional de Sistemas Acuáticos, CURE-Rocha, Universidad de la República, Uruguay; Sección Limnología, IECA, Facultad de Ciencias, Universidad de la República, Uruguay
| | | | - Martín A Montes
- NASA Goddard Space Flight Center, Terrestrial Information Systems Laboratory, Greenbelt, MD 20771, United States
| | - Angel M Segura
- Modelización y Análisis de Recursos Naturales, CURE Rocha, Universidad de la República, Uruguay
| | - Claudia Piccini
- Departamento de Microbiología, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), Montevideo, Uruguay.
| |
Collapse
|
32
|
The Comparative Toxicity of 10 Microcystin Congeners Administered Orally to Mice: Clinical Effects and Organ Toxicity. Toxins (Basel) 2020; 12:toxins12060403. [PMID: 32570788 PMCID: PMC7354475 DOI: 10.3390/toxins12060403] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/16/2020] [Accepted: 06/16/2020] [Indexed: 12/16/2022] Open
Abstract
Microcystins (MCs) are common cyanobacterial toxins that occur in freshwaters worldwide. Only two of the >200 MC variants have been tested for potential toxicity after oral exposure. This paper reports on the toxicity of 10 different MC congeners identified in algal blooms, microcystin-LR (MCLR), MCLA, MCLF, MCLW, MCLY, MCRR, [Asp3]MCRR, [Asp3,Dhb7]MCRR, MCWR, and MCYR after single administrations to BALB/c mice. In a preliminary MCLR dose–response study of 3 to 9 mg/kg doses, ≥5 mg/kg induced clinical changes, increased serum levels of ALT, AST, and GLDH, liver congestion, increased liver/body weight ratios, and reduced serum glucose and total protein. Based on the extent of these effects, the 10 congeners were administered as single 7 mg/kg oral doses and toxicity evaluated. The greatest toxicity was observed with MCLA and MCLR including a high percentage of moribundity. In addition to eliciting effects similar to those listed above for MCLR, MCLA also induced serum alterations indicative of jaundice. MCLY, and MCYR induced changes like those noted with MCLR, but to lesser extents. MCLW and MCLF exhibited some serum and morphological changes associated with hepatic toxicity, while there were few indications of toxicity after exposures to MCRR, [Asp3]MCRR, [Asp3,Dhb7]MCRR, or MCWR. These data illustrate a wide spectrum of hepatic effects and different potencies of these MC congeners.
Collapse
|
33
|
Zhao Y, Yan Y, Xie L, Wang L, He Y, Wan X, Xue Q. Long-term environmental exposure to microcystins increases the risk of nonalcoholic fatty liver disease in humans: A combined fisher-based investigation and murine model study. ENVIRONMENT INTERNATIONAL 2020; 138:105648. [PMID: 32187572 DOI: 10.1016/j.envint.2020.105648] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/21/2020] [Accepted: 03/08/2020] [Indexed: 06/10/2023]
Abstract
Microcystins (MCs) produced by cyanobacteria pose serious threats to human health. However, the contribution of long-term exposure to MCs to the development of nonalcoholic fatty liver disease (NAFLD) remains poorly documented. In this study, we estimated the environmental uptake of MCs by a small population of fishers who have lived for many years on Meiliang Bay of Lake Taihu, where cyanobacterial blooms occur frequently. Serum biochemical indices of liver function and their relationships with MC contamination in these people were also investigated. Moreover, to mimic the long-term effects of MC on the livers of fishers, an animal model was established in which mice were exposed to MC-LR at an environmentally relevant level, a reference level (the no-observed adverse effect level, NOAEL), and three times the NOAEL through drinking water for 12 months. We estimated the total daily intake of MCs by fishers through contaminated lake water and food to be 5.95 μg MC-LReq, far exceeding the tolerable daily intake (2.40 μg MC-LReq) proposed by the World Health Organization (WHO). More than 80% of participants had at least one abnormal serum marker. The indices of aspartate aminotransferase (AST)/alanine aminotransferase (ALT), triglyceride (TG), globulin (GLB), and lactate dehydrogenase (LDH) had close positive associations with MC contamination, indicating that both liver damage and lipid metabolism dysfunction were induced by chronic MC exposure. Furthermore, the animal experimental results showed that long-term exposure to MC-LR at the environmentally relevant level led to hepatic steatosis with molecular alterations in circadian rhythm regulation, lipid metabolic processes, and the cell cycle pathway. Exposure to MC-LR at or above the NOAEL worsened the pathological phenotype towards nonalcoholic steatohepatitis disease (NASH) or fibrosis. These results suggest that prolonged exposure to the reference level (NOAEL) of MC-LR could cause severe liver injury to mammals. People with long-term environmental exposure to MCs might be at high risk for developing NAFLD.
Collapse
Affiliation(s)
- Yanyan Zhao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China.
| | - Yunjun Yan
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, PR China
| | - Liqiang Xie
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China
| | - Lixiao Wang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, PR China
| | - Yaojia He
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, PR China
| | - Xiang Wan
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China
| | - Qingju Xue
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China
| |
Collapse
|
34
|
Santori N, Buratti FM, Scardala S, Dorne JLCM, Testai E. In vitro detoxication of microcystins in human samples: variability among variants with different hydrophilicity and structure. Toxicol Lett 2020; 322:131-139. [PMID: 31953209 DOI: 10.1016/j.toxlet.2020.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 01/07/2020] [Accepted: 01/11/2020] [Indexed: 10/25/2022]
Abstract
Cyanotoxins, among which >200 variants of Microcystins (MC), constitute an emerging issue in food safety. Microcystins (MC) toxicity is congener-specific; however, the in vitro inhibition of PP1/PP2A (the key molecular event of MC toxicity) by single MC variants is comparable and MC toxicokinetics seems to be the critical point. Here, the variability in GSH conjugation catalysed by human recombinant enzymes and human hepatic cytosol has been compared between hydrophilic (MC-LR and MC-RR) and hydrophobic (MC-LW, MC-YR and MC-LF) variants, according to measured logPow. In vitro detoxication reaction (spontaneous plus enzymatic) is favored by the variant hydrophilicity, with MC-LF very poorly detoxified. With MC-YR and -LW the spontaneous reaction always gave the major contribution, whereas with MC-LR and -RR the enzymatic reaction became by far predominant when GSH was depleted. Consequently, the well-known GST polymorphisms seems not to be the major driver for potential human variability in susceptibility towards the MC-toxicity, except for MC-RR and -LR when GSH is depleted. Looking at these results and literature data, MC-RR (the least cytotoxic and acutely toxic in rodents) is the more hydrophilic, has the lowest OATP-mediated hepatic uptake and the highest detoxication efficiency. The opposite is true for the most lipophilic MC-LF: once entered in the cells with the highest uptake, it is very poorly detoxified, and resulted as the most toxic in various cell types. MC-dependent TK should be considered in order to estimate the variability in toxicity and to support the use of quantitative in vitro-in vivo extrapolation models of single toxins and their mixtures co-occurring in the environment.
Collapse
Affiliation(s)
- Nicoletta Santori
- Istituto Superiore Di Sanità, Environment & Health Dept., Viale Regina Elena, 299, Rome Italy
| | - Franca Maria Buratti
- Istituto Superiore Di Sanità, Environment & Health Dept., Viale Regina Elena, 299, Rome Italy.
| | - Simona Scardala
- Istituto Superiore Di Sanità, Environment & Health Dept., Viale Regina Elena, 299, Rome Italy
| | | | - Emanuela Testai
- Istituto Superiore Di Sanità, Environment & Health Dept., Viale Regina Elena, 299, Rome Italy
| |
Collapse
|
35
|
Antiproliferative, neurotoxic, genotoxic and mutagenic effects of toxic cyanobacterial extracts. Interdiscip Toxicol 2019; 11:267-274. [PMID: 31762678 PMCID: PMC6853012 DOI: 10.2478/intox-2018-0026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 01/13/2018] [Indexed: 01/08/2023] Open
Abstract
Cyanobacteria are the rich resource of various secondary metabolites including toxins with broad pharmaceutical significance. The aim of this work was to evaluate the antiproliferative, neurotoxic, genotoxic and mutagenic effects of cyanobacterial extracts containing Microcystin-LR (MCLR) in vitro. ELISA analysis results showed that MCLR contents of five cyanobacterial extracts were 2.07 ng/mL, 1.43 ng/mL, 1.41 ng/mL, 1.27 ng/mL, and 1.12 ng/mL for Leptolyngbya sp. SB1, Phormidium sp. SB4, Oscillatoria earlei SB5, Phormidium sp. SB2, Uncultured cyanobacterium, respectively. Phormidium sp. SB4 and Phormidium sp. SB2 extracts had the lowest neurotoxicity (86% and 79% cell viability, respectively) and Oscillatoria earlei SB5 extracts had the highest neurotoxicity (47% cell viability) on PC12 cell at 1000 µg/ml extract concentration. Leptolyngbya sp. SB1 and Phormidium sp. SB2 showed the highest antiproliferative effect (92% and 77% cell death) on HT29 cell. On the other hand, all concentrations of five toxic cyanobacterial extracts induced DNA damage between 3.0% and 1.3% of tail intensity and did not cause any direct mutagenic effect at the 1000 µg/plate cyanobacterial extracts. These results suggest that cyanobacteria-derived MCLR is a promising candidate for development of effective agents against colon cancer.
Collapse
|
36
|
Tavares D, Paulino MG, Terezan AP, Batista Fernandes J, Giani A, Fernandes MN. Osmoregulatory disturbance in Neotropical fish exposed to the crude extracts of the cyanobacterium, Radiocystis fernandoi. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 216:105315. [PMID: 31561138 DOI: 10.1016/j.aquatox.2019.105315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 06/10/2023]
Abstract
Blooms of cyanobacteria, a common event in eutrophic environments, result in the release of potentially toxic substances into the water. The cyanobacterium Radiocystis fernandoi produces microcystin (MC) and other peptides that may disturb homeostasis. This study evaluated the effect of intraperitoneal injections containing the crude extract (CE) of R. fernandoi strain R28 on the gills and kidneys of neotropical fish, Piaractus mesopotamicus, 3, 6 and 24 h post-injection. CE contained MC-RR, MC-YR and minor other oligopeptides. Plasma ions and the activities of the enzymes PP1 and PP2A, Na+/K+-ATPase (NKA), H+-ATPase (HA) and carbonic anhydrase (CA) were determined and morphological changes in both the gills and kidneys were characterized. Compared to controls, the concentration of Na+ within the plasma of P. mesopotamicus decreased after treatment with CE 3 h post treatment and increased after 24 h; the concentration of K+ decreased after 6 h. The activity of the endogenous PP1 and PP2A was unchanged in the gills and was inhibited in the kidneys 6 h after i.p. injection. In the gills, NKA activity increased after 3 h and decreased 6 h post i.p. exposure. Further, NKA activity did not differ from the controls 24-h post injection. In the kidneys, NKA, HA and CA activities were unaffected by treatment. The mitochondria-rich cell (MRC) density in the gills decreased after 3 h in the filament and 3 and 6 h in the lamellae and was restored to the control levels 24 h post-exposure. Filament epithelial hyperplasia and hypertrophy, lamellar atrophy and rupture of the lamellar epithelium were the most common effects of treatment in the gills. No histopathological changes occurred in the kidneys. This study demonstrates that a single dose of toxic CE from R. fernandoi can cause a transitory ion imbalance in P. mesopotamicus which is related to the changes in MRC levels and NKA activity. Ionic balance was recovered 24 h post i.p. injection, however, morphological changes that occurred in the gills took a longer amount of time to return to normal. To conclude, the effects of components contained within the CE of R. fernandoi may be harmful to P. mesopotamicus. In particular, the recovery of ionic regulation depends on MRC responses and histopathological changes produced by CE may affect gas exchange and other gill functions.
Collapse
Affiliation(s)
- Driele Tavares
- Department of Physiological Sciences, Federal University of São Carlos, Rodovia Washington Luiz km 235, 13565-905 São Carlos, São Paulo, Brazil
| | - Marcelo Gustavo Paulino
- Department of Physiological Sciences, Federal University of São Carlos, Rodovia Washington Luiz km 235, 13565-905 São Carlos, São Paulo, Brazil
| | - Ana Paula Terezan
- Department of Chemistry, Federal University of São Carlos, Rodovia Washington Luiz km 235, 13565-905 São Carlos, São Paulo, Brazil
| | - João Batista Fernandes
- Department of Chemistry, Federal University of São Carlos, Rodovia Washington Luiz km 235, 13565-905 São Carlos, São Paulo, Brazil
| | - Alessandra Giani
- Department of Botany, Federal University of Minas Gerais, Av. Pres. Antônio Carlos, 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Marisa Narciso Fernandes
- Department of Physiological Sciences, Federal University of São Carlos, Rodovia Washington Luiz km 235, 13565-905 São Carlos, São Paulo, Brazil.
| |
Collapse
|
37
|
Simultaneous Detection of 14 Microcystin Congeners from Tissue Samples Using UPLC- ESI-MS/MS and Two Different Deuterated Synthetic Microcystins as Internal Standards. Toxins (Basel) 2019; 11:toxins11070388. [PMID: 31269739 PMCID: PMC6669509 DOI: 10.3390/toxins11070388] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 06/21/2019] [Accepted: 06/28/2019] [Indexed: 02/02/2023] Open
Abstract
Cyanobacterial microcystins (MCs), potent serine/threonine-phosphatase inhibitors, pose an increasing threat to humans. Current detection methods are optimised for water matrices with only a few MC congeners simultaneously detected. However, as MC congeners are known to differ in their toxicity, methods are needed that simultaneously quantify the congeners present, thus allowing for summary hazard and risk assessment. Moreover, detection of MCs should be expanded to complex matrices, e.g., blood and tissue samples, to verify in situ MC concentrations, thus providing for improved exposure assessment and hazard interpretation. To achieve this, we applied two synthetic deuterated MC standards and optimised the tissue extraction protocol for the simultaneous detection of 14 MC congeners in a single ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) run. This procedure was validated using plasma and liver homogenates of mice (male and female) spiked with deuterated MC standards. For proof of concept, tissue and plasma samples from mice i.p. injected with MC-LR and MC-LF were analysed. While MC-LF was detected in all tissue samples of both sexes, detection of MC-LR was restricted to liver samples of male mice, suggesting different toxicokinetics in males, e.g., transport, conjugation or protein binding. Thus, deconjugation/-proteinisation steps should be employed to improve detection of bound MC.
Collapse
|
38
|
Hinojosa MG, Gutiérrez-Praena D, Prieto AI, Guzmán-Guillén R, Jos A, Cameán AM. Neurotoxicity induced by microcystins and cylindrospermopsin: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 668:547-565. [PMID: 30856566 DOI: 10.1016/j.scitotenv.2019.02.426] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 05/26/2023]
Abstract
Microcystins (MCs) and cylindrospermopsin (CYN) are among the most frequent toxins produced by cyanobacteria. These toxic secondary metabolites are classified as hepatotoxins and cytotoxin, respectively. Furthermore, both may present the ability to induce damage to the nervous system. In this sense, there are many studies manifesting the potential of MCs to cause neurotoxicity both in vitro and in vivo, due to their probable capacity to cross the blood-brain-barrier through organic anion transporting polypeptides. Moreover, the presence of MCs has been detected in brain of several experimental models. Among the neurological effects, histopathological brain changes, deregulation of biochemical parameters in brain (production of oxidative stress and inhibition of protein phosphatases) and behavioral alterations have been described. It is noteworthy that minority variants such as MC-LF and -LW have demonstrated to exert higher neurotoxic effects compared to the most studied congener, MC-LR. By contrast, the available studies concerning CYN-neurotoxic effects are very scarce, mostly showing inflammation and apoptosis in neural murine cell lines, oxidative stress, and alteration of the acetylcholinesterase activity in vivo. However, more studies are required in order to clarify the neurotoxic potential of both toxins, as well as their possible contribution to neurodegenerative diseases.
Collapse
Affiliation(s)
- M G Hinojosa
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain
| | - D Gutiérrez-Praena
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain
| | - A I Prieto
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain.
| | - R Guzmán-Guillén
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain
| | - A Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain
| | - A M Cameán
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012 Seville, Spain
| |
Collapse
|
39
|
Hinojosa MG, Prieto AI, Gutiérrez-Praena D, Moreno FJ, Cameán AM, Jos A. Neurotoxic assessment of Microcystin-LR, cylindrospermopsin and their combination on the human neuroblastoma SH-SY5Y cell line. CHEMOSPHERE 2019; 224:751-764. [PMID: 30851527 DOI: 10.1016/j.chemosphere.2019.02.173] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/12/2019] [Accepted: 02/24/2019] [Indexed: 06/09/2023]
Abstract
Microcystin-LR (MC-LR) and Cylindrospermopsin (CYN) are produced by cyanobacteria. Although being considered as a hepatotoxin and a cytotoxin, respectively, different studies have revealed neurotoxic properties for both of them. The aim of the present work was to study their cytotoxic effects, alone and in combination, in the SH-SY5Y cell line. In addition, toxicity mechanisms such as oxidative stress and acetylcholinesterase (AChE) activity, and morphological studies were carried out. Results showed a cytotoxic response of the cells after their exposure to 0-100 μg/mL of MC-LR or 0-10 μg/mL CYN in both differentiated and undifferentiated cells. Thus, CYN resulted to be more toxic than MC-LR. Respect to their combination, a higher cytotoxic effect than the toxins alone in the case of undifferentiated cells, and almost a similar response to the presented by MC-LR in differentiated cells were observed. However, after analyzing this data with the isobolograms method, an antagonistic effect was mainly obtained. The oxidative stress study only showed an affectation of glutathione levels at the highest concentrations assayed of MC-LR and the combination in the undifferentiated cells. A significant increase in the AChE activity was observed after exposure to MC-LR in undifferentiated cells, and after exposure to the combination of both cyanotoxins on differentiated cells. However, CYN decreased the AChE activity only on differentiated cultures. Finally, the morphological study revealed different signs of cellular affectation, with apoptotic processes at all the concentrations assayed. Therefore, both cyanotoxins isolated and in combination, have demonstrated to cause neurotoxic effects in the SH-SY5Y cell line.
Collapse
Affiliation(s)
- M G Hinojosa
- Área de Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/Profesor García González 2, 41012, Sevilla, Spain
| | - A I Prieto
- Área de Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/Profesor García González 2, 41012, Sevilla, Spain
| | - D Gutiérrez-Praena
- Área de Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/Profesor García González 2, 41012, Sevilla, Spain.
| | - F J Moreno
- Área de Biología Celular, Facultad de Biología, Universidad de Sevilla, Avda. Reina Mercedes s/n, 41012, Sevilla, Spain
| | - A M Cameán
- Área de Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/Profesor García González 2, 41012, Sevilla, Spain
| | - A Jos
- Área de Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/Profesor García González 2, 41012, Sevilla, Spain
| |
Collapse
|
40
|
Wang Q, Liu Y, Guo J, Lin S, Wang Y, Yin T, Gregersen H, Hu T, Wang G. Microcystin-LR induces angiodysplasia and vascular dysfunction through promoting cell apoptosis by the mitochondrial signaling pathway. CHEMOSPHERE 2019; 218:438-448. [PMID: 30485828 DOI: 10.1016/j.chemosphere.2018.11.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/25/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
The harmful algal blooms are becoming increasingly problematic in the regions that drinking water production depends on surface waters. With a global occurrence, microcystins are toxic peptides produced by multiple cyanobacterial genera in the harmful algal blooms. In this study, we examined the effects of microcystin-LR (MC-LR), a representative toxin of the microcystin family, on vascular development in zebrafish and the apoptosis of human umbilical vein endothelial cells (HUVECs). In zebrafish larvae, MC-LR induced angiodysplasia, damaged vascular structures and reduced lumen size at 0.1 μM and 1 μM, leading to the decrease of the blood flow area in the blood vessels and brain hemorrhage, which showed that MC-LR could dose-dependently inhibit vascular development and cause vascular dysfunction. In MC-LR treated HUVECs, the proportion of early apoptosis and late apoptosis cells increased in a concentration-dependent manner. Different concentrations of MC-LR could also activate caspase 3/9 in HUVECs, increase the level of mitochondrial ROS and reduce mitochondrial membrane potential. Additionally, MC-LR could promote the expression of p53 and inhibit the expression of PCNA. The findings showed that MC-LR could promote apoptosis of HUVECs through the mitochondrial signaling pathway. Combined with these results, MC-LR may promote vascular endothelial cell apoptosis through mitochondrial signaling pathway, leading to angiodysplasia and vascular dysfunction.
Collapse
Affiliation(s)
- Qilong Wang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Yuanli Liu
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Jingsong Guo
- Key Laboratory of the Three Gorges Reservoir's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China
| | - Song Lin
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Yeqi Wang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Tieying Yin
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Hans Gregersen
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China
| | - Tingzhang Hu
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China.
| | - Guixue Wang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), State and Local Joint Engineering Laboratory for Vascular Implants (Chongqing), Bioengineering College of Chongqing University, Chongqing 400030, China.
| |
Collapse
|
41
|
Díez-Quijada L, Prieto AI, Guzmán-Guillén R, Jos A, Cameán AM. Occurrence and toxicity of microcystin congeners other than MC-LR and MC-RR: A review. Food Chem Toxicol 2018; 125:106-132. [PMID: 30597222 DOI: 10.1016/j.fct.2018.12.042] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/29/2018] [Accepted: 12/25/2018] [Indexed: 12/11/2022]
Abstract
The occurrence of cyanobacterial toxins is being increasingly reported. This is a reason for concern as they can induce toxic effects both in humans and in the environment. Among them, microcystins (MCs) are the best described and most diverse group of cyanobacterial toxins, and MC-LR and MC-RR are the congeners most widely investigated. However, the number of MC variants has also increased in recent years. Some of these minority variants have been shown to have a different toxicokinetic and toxicodynamic profile, but research focused on them is still limited. Moreover, in some water bodies these minority variants can be the predominant toxins. Nonetheless, MC-LR is the only one used for risk evaluation purposes at present. In order to contribute to more realistic risk assessments in the future, the aim of this review was to compile the available information in the scientific literature regarding the occurrence and concentration of minority MCs in water and food samples, and their toxic effects. The data retrieved demonstrate the congener-specific toxicity of MCs, as well as many data gaps in relation to analytical or mechanistic aspects, among others. Therefore, further research is needed to improve the toxicological characterization of these toxins and the exposure scenarios.
Collapse
Affiliation(s)
- Leticia Díez-Quijada
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Ana I Prieto
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Remedios Guzmán-Guillén
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| | - Angeles Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain.
| | - Ana M Cameán
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, C/Profesor García González 2, 41012, Seville, Spain
| |
Collapse
|
42
|
Wang X, Xu L, Li X, Chen J, Zhou W, Sun J, Wang Y. The differential effects of microcystin-LR on mitochondrial DNA in the hippocampus and cerebral cortex. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 240:68-76. [PMID: 29729571 DOI: 10.1016/j.envpol.2018.04.103] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 04/23/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Microcystin-LR (MC-LR) is the most abundant toxicant among microcystin variants produced by cyanobacteria. MC-induced toxicity is broadly reported to pose a threat to aquatic animals and humans and has been associated with the dysfunction of some organs such as liver and kidney. However, MC-induced neurotoxicity has not been well characterized after long-term exposure. This study was designed to investigate the neurotoxic effects after chronic oral administration of MC-LR. In our trial, C57/BL6 mice received MC-LR at 0, 1, 5, 10, 20 and 40 μg/L in drinking water for twelve months. Our data demonstrated that mitochondrial DNA (mtDNA) damage was evident in the damaged neurons as a result of chronic exposure. Histopathological abnormalities and mtDNA damage were observed in the hippocampus and cerebral cortex. Furthermore, MC-LR exerted distinct effects on these two brain regions. The hippocampus was more susceptible to the treatment of MC-LR compared with the cerebral cortex. However, no strong relationships were observed between the genotoxic effects and exposure doses. In conclusion, this study has provided a mtDNA-related mechanism for underlying chronic neurotoxicity of MC-LR and suggested the presence of differential toxicant effects on the hippocampus and cerebral cortex.
Collapse
Affiliation(s)
- Xiaofen Wang
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Lizhi Xu
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China; Experimental Center of Basic Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Xinxiu Li
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Jingwen Chen
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Wei Zhou
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Jiapeng Sun
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China
| | - Yaping Wang
- Department of Medical Genetics, Nanjing University School of Medicine, Nanjing, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University School of Medicine, Nanjing, China.
| |
Collapse
|
43
|
Beversdorf LJ, Rude K, Weirich CA, Bartlett SL, Seaman M, Kozik C, Biese P, Gosz T, Suha M, Stempa C, Shaw C, Hedman C, Piatt JJ, Miller TR. Analysis of cyanobacterial metabolites in surface and raw drinking waters reveals more than microcystin. WATER RESEARCH 2018; 140:280-290. [PMID: 29729580 DOI: 10.1016/j.watres.2018.04.032] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/10/2018] [Accepted: 04/14/2018] [Indexed: 05/26/2023]
Abstract
Freshwater cyanobacterial blooms are becoming increasingly problematic in regions that rely on surface waters for drinking water production. Microcystins (MCs) are toxic peptides produced by multiple cyanobacterial genera with a global occurrence. Cyanobacteria also produce a variety of other toxic and/or otherwise bioactive peptides (TBPs) that have gained less attention including cyanopeptolins (Cpts), anabaenopeptins (Apts), and microginins (Mgn). In this study, we compared temporal and spatial trends of four MCs (MCLR, MCRR, MCYR, MCLA), three Cpts (Cpt1020, Cpt1041, Cpt1007), two Apts (AptF, AptB), and Mgn690 in raw drinking water and at six surface water locations above these drinking water intakes in a eutrophic lake. All four MC congeners and five of six TBPs were detected in lake and raw drinking water. Across all samples, MCLR was the most frequently detected metabolite (100% of samples) followed by MCRR (97%) > Cpt1007 (74%) > MCYR (69%) > AptF (67%) > MCLA (61%) > AptB (54%) > Mgn690 (29%) and Cpt1041 (15%). Mean concentrations of MCs, Apts, and Cpts into two drinking water intakes were 3.9 ± 4.7, 0.14 ± 0.21, and 0.38 ± 0.92, respectively. Mean concentrations in surface water were significantly higher (p < 0.05) than in drinking water intakes for MCs but not for Cpts and Apts. Temporal trends in MCs, Cpts, and Apts in the two raw drinking water intakes were significantly correlated (p < 0.05) with measures of cell abundance (chlorophyll-a, Microcystis cell density), UV absorbance, and turbidity in surface water. This study expands current information about cyanobacterial TBPs that occur in lakes and that enter drinking water treatment plants and underscores the need to determine the fate of less studied cyanobacterial metabolites during drinking water treatment that may exacerbate toxicity of more well-known cyanobacterial toxins.
Collapse
Affiliation(s)
- Lucas J Beversdorf
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Kayla Rude
- Department of Chemistry, Carroll University, Waukesha, WI, USA
| | - Chelsea A Weirich
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Sarah L Bartlett
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Mary Seaman
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Christine Kozik
- Department of Biological Sciences, University of Wisconsin - Milwaukee, WI, USA
| | - Peter Biese
- Menasha Drinking Water Treatment Plant, Menasha, WI, USA
| | - Timothy Gosz
- Menasha Drinking Water Treatment Plant, Menasha, WI, USA
| | - Michael Suha
- Appleton Drinking Water Treatment Plant, Menasha, WI, USA
| | | | | | - Curtis Hedman
- Wisconsin State Laboratory of Hygiene, Madison, WI, USA
| | - Joseph J Piatt
- Department of Chemistry, Carroll University, Waukesha, WI, USA
| | - Todd R Miller
- Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.
| |
Collapse
|
44
|
Microcystin-LR-Triggered Neuronal Toxicity in Whitefish Does Not Involve MiR124-3p. Neurotox Res 2018; 35:29-40. [PMID: 29882005 PMCID: PMC6313356 DOI: 10.1007/s12640-018-9920-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 05/28/2018] [Accepted: 05/30/2018] [Indexed: 02/07/2023]
Abstract
Microcystin-LR (MC-LR) is a potent hepatotoxin that has also been pointed out of causing neurotoxicity, but the exact mechanisms of action still remain ambiguous and need to be elucidated. Data from studies on mammals show that pathology of astrocyte cells points to perturbations of microRNA signaling. Glial fibrillary acidic protein (GFAP), a neuronal cell/astrocyte-specific protein, and a microRNA-124-3p (MiR124-3p) are among putative triggers and regulators of neuronal cell/astrocyte reactivity. In the present study on whitefish (Coregonus lavaretus), we found that gfap mRNA contains a putative target site for MIR124-3p, to potentially affect its expression changes. qPCR expression study of gfap:MiR124-3p pair in the midbrain of juvenile whitefish, during 28 days of exposure to a repeated subacute dose of MC-LR (100 μg kg−1 body mass), showed marginally significant up-regulation of gfap only on the 7th day of exposure period which suggests neuronal toxicity. During the whole exposure period, neither midbrain nor blood plasma levels of MiR124-3p were changed. Furthermore, double luciferase gene reporter assay confirmed the lack of MiR124-3p involvement in mediating control over gfap mRNA expression. These data show that, although MC-LR may trigger neuronal toxicity in whitefish, this does not involve MiR124-3p in response to the treatment.
Collapse
|
45
|
Casquilho NV, Moreira-Gomes MD, Magalhães CB, Okuro RT, Ortenzi VH, Feitosa-Lima EK, Lima LM, Barreiro EJ, Soares RM, Azevedo SMFO, Valença SS, Fortunato RS, Carvalho AR, Zin WA. Oxidative imbalance in mice intoxicated by microcystin-LR can be minimized. Toxicon 2018; 144:75-82. [PMID: 29454806 DOI: 10.1016/j.toxicon.2018.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/09/2018] [Accepted: 02/13/2018] [Indexed: 12/19/2022]
Abstract
Microcystins-LR (MC-LR) is a cyanotoxin produced by cyanobacteria. We evaluated the antioxidant potential of LASSBio-596 (LB-596, inhibitor of phosphodiesterases 4 and 5), per os, and biochemical markers involved in lung and liver injury induced by exposure to sublethal dose of MC-LR. Fifty male Swiss mice received an intraperitoneal injection of 60 μL of saline (CTRL group, n = 20) or a sublethal dose of MC-LR (40 μg/kg, TOX group, n = 20). After 6 h the animals received either saline (TOX and CTRL groups) or LB-596 (50 mg/kg, TOX + LASS group, n = 10) by gavage. At 6 h after exposure, respiratory mechanics was evaluated in 10 CTRL and 10 TOX mice: there was a significant increase of all lung mechanics parameters (static elastance, viscoelastic component of elastance and lung resistive and viscoelastic/inhomogeneous pressures) in TOX compared to CTRL. 8 h after saline or MC-LR administration, i.e., 2 h after treatment with LB-596, blood serum levels of alanine aminotransferase and aspartate aminotransferase, activity of superoxide dismutase, catalase, and content of malondialdehyde and carbonyl in lung and liver, NADPH oxidase 2 and 4 mRNA expressions, dual oxidase enzyme activity and H2O2 generation were analyzed in lung homogenates. All parameters were significantly higher in TOX than in the other groups. There was no significant difference between CTRL and TOX + LASS. MC-LR deteriorated lung and liver functions and induced redox imbalance in them, which was prevented by oral administration of LB-596.
Collapse
Affiliation(s)
- Natália V Casquilho
- Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria Diana Moreira-Gomes
- Laboratory of Respiratory Physiology and Biochemistry, Superior Institute of Biomedical Sciences, Universidade Estadual do Ceará, Fortaleza, Brazil
| | - Clarissa B Magalhães
- Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Renata T Okuro
- Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Victor Hugo Ortenzi
- Laboratory of Molecular Radiobiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Emanuel K Feitosa-Lima
- Laboratory of Biology Redox, Institute of Biomedical Sciences, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lidia M Lima
- Laboratory of Evaluation and Synthesis of Bioactive Substances (LASSBio(®)), Institute of Biomedical Sciences, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Eliezer J Barreiro
- Laboratory of Evaluation and Synthesis of Bioactive Substances (LASSBio(®)), Institute of Biomedical Sciences, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Raquel M Soares
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; NUMPEX-BIO - Multidisciplinar Center of Biological Research, Universidade Federal do Rio de Janeiro, Polo Xerém, Duque de Caxias, RJ, Brazil
| | - Sandra M F O Azevedo
- Laboratory of Ecophysiology and Toxicology of Cyanobacteria, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Samuel S Valença
- Laboratory of Biology Redox, Institute of Biomedical Sciences, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo S Fortunato
- Laboratory of Molecular Radiobiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alysson Roncally Carvalho
- Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Walter A Zin
- Laboratory of Respiration Physiology, Carlos Chagas Filho Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
| |
Collapse
|
46
|
Biosynthesis of microcystin hepatotoxins in the cyanobacterial genus Fischerella. Toxicon 2017; 141:43-50. [PMID: 29154789 DOI: 10.1016/j.toxicon.2017.10.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 10/18/2017] [Accepted: 10/22/2017] [Indexed: 01/13/2023]
Abstract
Microcystins (MCs) are serine/threonine phosphatase inhibitors synthesized by several members of the phylum Cyanobacteria. Mining the draft genome sequence of the nostocalean MC-producing Fischerella sp. strain CENA161 led to the identification of three contigs containing mcy genes. Subsequent PCR and Sanger sequencing allowed the assembling of its complete biosynthetic mcy gene cluster with 55,016 bases in length. The cluster encoding ten genes (mcyA-J) with a central bidirectional promoter was organized in a similar manner as found in other genera of nostocalean cyanobacteria. However, the nucleotide sequence of the mcy gene cluster of Fischerella sp. CENA161 showed significant differences from all the other MC-producing cyanobacterial genera, sharing only 85.2 to 74.1% identities. Potential MC variants produced by Fischerella sp. CENA161 were predicted by the analysis of the adenylation domain binding pockets and further investigated by LC-MS/MS analysis. To our knowledge, this study presents the first complete mcy cluster characterization from a strain of the genus Fischerella, providing new insight into the distribution and evolution of MCs in the phylum Cyanobacteria.
Collapse
|
47
|
Xiong W, Tang Y, Shao C, Zhao Y, Jin B, Huang T, Miao Y, Shu L, Ma W, Xu X, Tang R. Prevention of Cyanobacterial Blooms Using Nanosilica: A Biomineralization-Inspired Strategy. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:12717-12726. [PMID: 28949533 DOI: 10.1021/acs.est.7b02985] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Cyanobacterial blooms represent a significant threat to global water resources because blooming cyanobacteria deplete oxygen and release cyanotoxins, which cause the mass death of aquatic organisms. In nature, a large biomass volume of cyanobacteria is a precondition for a bloom, and the cyanobacteria buoyancy is a key parameter for inducing the dense accumulation of cells on the water surface. Therefore, blooms will likely be curtailed if buoyancy is inhibited. Inspired by diatoms with naturally generated silica shells, we found that silica nanoparticles can be spontaneously incorporated onto cyanobacteria in the presence of poly(diallyldimethylammonium chloride), a cationic polyelectrolyte that can simulate biosilicification proteins. The resulting cyanobacteria-SiO2 complexes can remain sedimentary in water. This strategy significantly inhibited the photoautotrophic growth of the cyanobacteria and decreased their biomass accumulation, which could effectively suppress harmful bloom events. Consequently, several of the adverse consequences of cyanobacteria blooms in water bodies, including oxygen consumption and microcystin release, were significantly alleviated. Based on the above results, we propose that the silica nanoparticle treatment has the potential for use as an efficient strategy for preventing cyanobacteria blooms.
Collapse
Affiliation(s)
- Wei Xiong
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
| | - Yiming Tang
- College of Life and Environmental Science, Shanghai Normal University , Shanghai 200234, China
| | - Changyu Shao
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
| | - Yueqi Zhao
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
- Qiushi Academy for Advanced Studies, Zhejiang University , Hangzhou 310027, China
| | - Biao Jin
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
| | - Tingting Huang
- College of Life and Environmental Science, Shanghai Normal University , Shanghai 200234, China
| | - Ya'nan Miao
- College of Life and Environmental Science, Shanghai Normal University , Shanghai 200234, China
| | - Lei Shu
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
- Qiushi Academy for Advanced Studies, Zhejiang University , Hangzhou 310027, China
| | - Weimin Ma
- College of Life and Environmental Science, Shanghai Normal University , Shanghai 200234, China
| | - Xurong Xu
- Qiushi Academy for Advanced Studies, Zhejiang University , Hangzhou 310027, China
| | - Ruikang Tang
- Center for Biomaterials and Biopathways, Department of Chemistry, Zhejiang University , Hangzhou 310027, China
| |
Collapse
|
48
|
Lin W, Hou J, Guo H, Qiu Y, Li L, Li D, Tang R. Dualistic immunomodulation of sub-chronic microcystin-LR exposure on the innate-immune defense system in male zebrafish. CHEMOSPHERE 2017; 183:315-322. [PMID: 28551208 DOI: 10.1016/j.chemosphere.2017.05.079] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 05/11/2017] [Accepted: 05/12/2017] [Indexed: 06/07/2023]
Abstract
Microcystins (MCs), produced by toxic cyanobacterial blooms that appeared world wildly in eutrophication waters, have often caused fish illness and even massive death cases. Among at least 90 structural variants, microcystin-LR (MC-LR) is the most common and toxic variant. In order to better understand innate immune responses in fish disrupted by environmental concentrations of MC-LR, male zebrafish (Danio rerio) were exposed to 0, 0.3, 1, 3, 10 and 30 μg/L MC-LR for 30 d, and the changes in splenic pathology and immunological gene expression as well as serum immune parameters were studied. In the low concentration groups (0.3, 1 and 3 μg/L), zebrafish displayed splenic inflammatory changes including the formation of melano-macrophage centers and the increase of macrophage pseudopodia, remarkable elevation of serum C3 levels, and significantly upregulated expression of innate immune-related genes (c3b, lyz, il1β, tnfα and ifnγ). In contrast, high concentrations of MC-LR (10 and 30 μg/L) resulted in the degeneration of splenic lymphocytes and macrophages, and down-regulation of immune-related genes as well as significant decreases in the level of serum C3. Furthermore, significant increases in the activity of serum ACP and ALP suggested that high concentrations of MC-LR increased permeability of macrophage plasma membrane or cellular necrosis, and subsequently decreased innate immune function. Our findings illustrated that sub-chronic exposure of MC-LR has dualistic influences on fish innate immune system with inflammatory activation at low exposure concentrations but turned to immune inhibition with the increases of exposure concentration.
Collapse
Affiliation(s)
- Wang Lin
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jie Hou
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Honghui Guo
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Yuming Qiu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Li Li
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, PR China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, Wuhan 430070, PR China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PR China.
| | - Dapeng Li
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, PR China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, Wuhan 430070, PR China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PR China
| | - Rong Tang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, PR China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, Wuhan 430070, PR China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PR China
| |
Collapse
|
49
|
Mello FD, Braidy N, Marçal H, Guillemin G, Nabavi SM, Neilan BA. Mechanisms and Effects Posed by Neurotoxic Products of Cyanobacteria/Microbial Eukaryotes/Dinoflagellates in Algae Blooms: a Review. Neurotox Res 2017; 33:153-167. [PMID: 28836116 DOI: 10.1007/s12640-017-9780-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/28/2017] [Accepted: 07/05/2017] [Indexed: 12/12/2022]
Abstract
Environmental toxins produced by cyanobacteria and dinoflagellates have increasingly become a public health concern due to their ability to damage several tissues in humans. In particular, emerging evidence has called attention to the neurodegenerative effects of the cyanobacterial toxin β-N-methylamino-L-alanine (BMAA). Furthermore, other toxins such as anatoxin, saxitoxin, microcystin, nodularin and ciguatoxin also have a different range of effects on human tissues, including hepatotoxicity, neurotoxicity and gastrointestinal irritation. However, the vast majority of known environmental toxins have not yet been examined in the context of neurodegenerative disease. This review aims to investigate whether neurotoxic mechanisms can be demonstrated in all aforementioned toxins, and whether there exists a link to neurodegeneration. Management of toxin exposure and potential neuroprotective compounds is also discussed. Collectively, all aforementioned microbial toxins are likely to exert some form of neuronal damage, with many of their modes of action consistent with neurodegeneration. This is important in advancing our current understanding of the cytotoxic potential of environmental toxins upon human brain function, particularly in the context of age-related neurodegenerative disease.
Collapse
Affiliation(s)
- Fiona D Mello
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, Faculty of Medicine, The University of New South Wales, Sydney, Australia
| | - Helder Marçal
- Graduate School of Biomedical Engineering, Faculty of Engineering, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Gilles Guillemin
- Neuropharmacology group, MND and Neurodegenerative diseases Research Centre, Macquarie University, Sydney, NSW, Australia
| | - Seyed Mohammad Nabavi
- Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Brett A Neilan
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia.
| |
Collapse
|
50
|
McLellan NL, Manderville RA. Toxic mechanisms of microcystins in mammals. Toxicol Res (Camb) 2017; 6:391-405. [PMID: 30090507 PMCID: PMC6060792 DOI: 10.1039/c7tx00043j] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/21/2017] [Indexed: 01/08/2023] Open
Abstract
Microcystins, such as microcystin-leucine arginine (MC-LR), are some of the most toxic and prevalent cyanotoxins produced by cyanobacteria in freshwater and saltwater algal blooms worldwide. Acute and chronic exposures to microcystins are primarily known to cause hepatotoxicity; cellular damage and genotoxicity within mammalian livers. However, in vivo studies indicate that similar damage may occur in other mammalian organs and tissues, such as the kidney, heart, reproductive systems, and lungs - particularly following chronic low-dose exposures. Mechanisms of toxicity of mycrocystins are reviewed herein; including cellular uptake, interaction with protein phosphatases PP1 and PP2A, cytoskeletal effects, formation of oxidative stress and induction of apoptosis. In general, the mode of action of toxicity by MCs in mammalian organs are similar to those that have been observed in liver tissues. A comprehensive understanding of the toxic mechanisms of microcystins in mammalian tissues and organs will assist in the development of risk assessment approaches to public health protection strategies and the development of robust drinking water policies.
Collapse
Affiliation(s)
- Nicole L McLellan
- School of Environmental Sciences , University of Guelph , Guelph , Ontario N1G 2W1 , Canada
| | - Richard A Manderville
- Department of Chemistry and Toxicology , University of Guelph , Guelph , Ontario N1G 2W1 , Canada . ; ; Tel: +1-519-824-4120, x53963
| |
Collapse
|