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Lin Q, Jing Y, Yan C, Chen X, Zhang Q, Lin X, Xu Y, Chen B. Design and Application of pH-Responsive Liposomes for Site-Specific Delivery of Cytotoxin from Cobra Venom. Int J Nanomedicine 2024; 19:5381-5395. [PMID: 38859950 PMCID: PMC11164093 DOI: 10.2147/ijn.s461728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 05/25/2024] [Indexed: 06/12/2024] Open
Abstract
Background Current immunotherapies with unexpected severe side effects and treatment resistance have not resulted in the desired outcomes for patients with melanoma, and there is a need to discover more effective medications. Cytotoxin (CTX) from Cobra Venom has been established to have favorable cytolytic activity and antitumor efficacy and is regarded as a promising novel anticancer agent. However, amphiphilic CTX with excellent anionic phosphatidylserine lipid-binding ability may also damage normal cells. Methods We developed pH-responsive liposomes with a high CTX load (CTX@PSL) for targeted acidic-stimuli release of drugs in the tumor microenvironment. The morphology, size, zeta potential, drug-release kinetics, and preservation stability were characterized. Cell uptake, apoptosis-promoting effects, and cytotoxicity were assessed using MTT assay and flow cytometry. Finally, the tissue distribution and antitumor effects of CTX@PSL were systematically assessed using an in vivo imaging system. Results CTX@PSL exhibited high drug entrapment efficiency, drug loading, stability, and a rapid release profile under acidic conditions. These nanoparticles, irregularly spherical in shape and small in size, can effectively accumulate at tumor sites (six times higher than free CTX) and are rapidly internalized into cancer cells (2.5-fold higher cell uptake efficiency). CTX@PSL displayed significantly stronger cytotoxicity (IC50 0.25 μg/mL) and increased apoptosis in than the other formulations (apoptosis rate 71.78±1.70%). CTX@PSL showed considerably better tumor inhibition efficacy than free CTX or conventional liposomes (tumor inhibition rate 79.78±5.93%). Conclusion Our results suggest that CTX@PSL improves tumor-site accumulation and intracellular uptake for sustained and targeted CTX release. By combining the advantages of CTX and stimuli-responsive nanotechnology, the novel CTX@PSL nanoformulation is a promising therapeutic candidate for cancer treatment.
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Affiliation(s)
- Qing Lin
- Department of Pharmacy, Affiliated Fuzhou First Hospital of Fujian Medical University, Fujian Medical University, Fuzhou, Fujian, People’s Republic of China
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
| | - Yafei Jing
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
- Key Laboratory of Nanomedical Technology (Education Department of Fujian Province), Fujian Medical University, Fuzhou, Fujian, People’s Republic of China
| | - Cailing Yan
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
| | - Xinyi Chen
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
| | - Qiong Zhang
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
| | - Xinhua Lin
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
- Key Laboratory of Nanomedical Technology (Education Department of Fujian Province), Fujian Medical University, Fuzhou, Fujian, People’s Republic of China
| | - Yunlu Xu
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
- Center of Translational Hematology, Fujian Medical University Union Hospital, Fujian Medical University, Fuzhou, Fujian, People’s Republic of China
| | - Bing Chen
- School of Pharmacy, Fujian Medical University, Fujian, People’s Republic of China
- Key Laboratory of Nanomedical Technology (Education Department of Fujian Province), Fujian Medical University, Fuzhou, Fujian, People’s Republic of China
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Li M, Gasanoff ES. Cationic Proteins Rich in Lysine Residue Trigger Formation of Non-bilayer Lipid Phases in Model and Biological Membranes: Biophysical Methods of Study. J Membr Biol 2023; 256:373-391. [PMID: 37735238 DOI: 10.1007/s00232-023-00292-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 09/05/2023] [Indexed: 09/23/2023]
Abstract
Cationic membrane-active toxins are the most abundant group of proteins in the venom of snakes and insects. Cationic proteins such as cobra venom cytotoxin and bee venom melittin are known for their pharmacological reactions including anticancer and antimicrobial effects which arise from the toxin-induced alteration in the dynamics and structure of plasma membranes and membranes of organelles. It has been established that these cationic toxins trigger the formation of non-bilayer lipid phase transitions in artificial and native mitochondrial membranes. Remarkably, the toxin-induced formation of non-bilayer lipid phase increases at certain conditions mitochondrial ATP synthase activity. This observation opens an intriguing avenue for using cationic toxins in the development of novel drugs for the treatment of cellular energy deficiency caused by aging and diseases. This observation also warrants a thorough investigation of the molecular mechanism(s) of lipid phase polymorphisms triggered by cationic proteins. This article presents a review on the application of powerful biophysical methods such as resonance spectroscopy (31P-, 1H-, 2H-nuclear magnetic resonance, and electron paramagnetic resonance), luminescence, and differential scanning microcalorimetry in studies of non-bilayer lipid phase transitions triggered by cationic proteins in artificial and biological membranes. A phenomenon of the triggered by cationic proteins the non-bilayer lipid phase transitions occurring within 10-2-10-11 s is discussed in the context of potential pharmacological applications of cationic proteins. Next to the ATP dimer is an inverted micelle made of cardiolipin that serves as a vehicle for the transport of H+ ions from the intra-crista space to the matrix. It is proposed that such inverted micelles are triggered by the high density of H+ ions and the cationic proteins rich in lysine residue which compete with the conserved lysine residues of the ATP synthase rotor for binding to cardiolipin in the inner mitochondrial membrane and perturb the bilayer lipid packing of cristae. Phospholipids with a blue polar head represent cardiolipin and those with a red polar head represent other phospholipids found in the crista membrane.
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Affiliation(s)
- Meiyi Li
- STEM Research Centre, Science Department, Chaoyang Kaiwen Academy, Beijing, 100018, China
| | - Edward S Gasanoff
- STEM Research Centre, Science Department, Chaoyang Kaiwen Academy, Beijing, 100018, China.
- Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
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Hiu JJ, Fung JKY, Tan HS, Yap MKK. Unveiling the functional epitopes of cobra venom cytotoxin by immunoinformatics and epitope-omic analyses. Sci Rep 2023; 13:12271. [PMID: 37507457 PMCID: PMC10382524 DOI: 10.1038/s41598-023-39222-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 07/21/2023] [Indexed: 07/30/2023] Open
Abstract
Approximate 70% of cobra venom is composed of cytotoxin (CTX), which is responsible for the dermonecrotic symptoms of cobra envenomation. However, CTX is generally low in immunogenicity, and the antivenom is ineffective in attenuating its in vivo toxicity. Furthermore, little is known about its epitope properties for empirical antivenom therapy. This study aimed to determine the epitope sequences of CTX using the immunoinformatic analyses and epitope-omics profiling. A conserved CTX was used in this study to determine its T-cell and B-cell epitope sequences using immunoinformatic tools and molecular docking simulation with different Human Leukocyte Antigens (HLAs). The potential T-cell and B-cell epitopes were 'KLVPLFY,' 'CPAGKNLCY,' 'MFMVSTPTK,' and 'DVCPKNSLL.' Molecular docking simulations disclosed that the HLA-B62 supertype exhibited the greatest binding affinity towards cobra venom cytotoxin. The namely L7, G18, K19, N20, M25, K33, V43, C44, K46, N47, and S48 of CTX exhibited prominent intermolecular interactions with HLA-B62. The multi-enzymatic-limited-digestion/liquid chromatography-mass spectrometry (MELD/LC-MS) also revealed three potential epitope sequences as 'LVPLFYK,' 'MFMVS,' and 'TVPVKR'. From different epitope mapping approaches, we concluded four potential epitope sites of CTX as 'KLVPLFYK', 'AGKNL', 'MFMVSTPKVPV' and 'DVCPKNSLL'. Site-directed mutagenesis of these epitopes confirmed their locations at the functional loops of CTX. These epitope sequences are crucial to CTX's structural folding and cytotoxicity. The results concluded the epitopes that resided within the functional loops constituted potential targets to fabricate synthetic epitopes for CTX-targeted antivenom production.
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Affiliation(s)
- Jia Jin Hiu
- School of Science, Monash University Malaysia, 47500, Bandar Sunway, Malaysia
| | - Jared Kah Yin Fung
- School of Science, Monash University Malaysia, 47500, Bandar Sunway, Malaysia
| | - Hock Siew Tan
- School of Science, Monash University Malaysia, 47500, Bandar Sunway, Malaysia
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Misuan N, Mohamad S, Tubiana T, Yap MKK. Ensemble-based molecular docking and spectrofluorometric analysis of interaction between cytotoxin and tumor necrosis factor receptor 1. J Biomol Struct Dyn 2023; 41:15339-15353. [PMID: 36927291 DOI: 10.1080/07391102.2023.2188945] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/28/2023] [Indexed: 03/18/2023]
Abstract
Cytotoxin (CTX) is a three-finger toxin presents predominantly in cobra venom. The functional site of the toxin is located at its three hydrophobic loop tips. Its actual mechanism of cytotoxicity remains inconclusive as few conflicting hypotheses have been proposed in addition to direct cytolytic effects. The present work investigated the interaction between CTX and death receptor families via ensemble-based molecular docking and fluorescence titration analysis. Multiple sequence alignments of different CTX isoforms obtained a conserved CTX sequence. The three-dimensional structure of the conserved CTX was later determined using homology modelling, and its quality was validated. Ensemble-based molecular docking of CTX was performed with different death receptors, such as Fas-ligand and tumor necrosis factor receptor families. Our results showed that tumor necrosis factor receptor 1 (TNFR1) was the best receptor interacting with CTX attributed to the interaction of all three functional loops and evinced with low HADDOCK, Z-score and RMSD value. The interaction between CTX and TNFR1 was also supported by a concentration-dependent reduction of fluorescence intensity with increasing binding affinity. The possible intermolecular interactions between CTX and TNFR1 were Van der Waals forces and hydrogen bonding. Our findings suggest a possibility that CTX triggers apoptosis cell death through non-covalent interactions with TNFR1.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Nurhamimah Misuan
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Saharuddin Mohamad
- Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), University of Malaya, Kuala Lumpur, Malaysia
| | - Thibault Tubiana
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Michelle Khai Khun Yap
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia
- Tropical Medicine and Biology Multidisciplinary Platform, Bandar Sunway, Malaysia
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The secretory phenotypes of envenomed cells: Insights into venom cytotoxicity. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 133:193-230. [PMID: 36707202 DOI: 10.1016/bs.apcsb.2022.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Snake envenomation is listed as Category A Neglected Tropical Diseases (NTD) by World Health Organization, indicates a severe public health problem. The global figures for envenomation cases are estimated to be more than 1.8 million annually. Even if the affected victims survive the envenomation, they might suffer from permanent morbidity due to local envenomation. One of the most prominent local envenomation is dermonecrosis. Dermonecrosis is a pathophysiological outcome of envenomation that often causes disability in the victims due to surgical amputations, deformities, contracture, and chronic ulceration. The key venom toxins associated with this local symptom are mainly attributed to substantial levels of enzymatic and non-enzymatic toxins as well as their possible synergistic actions. Despite so, the severity of the local tissue damage is based on macroscopic observation of the bite areas. Furthermore, limited knowledge is known about the key biomarkers involved in the pathogenesis of dermonecrosis. The current immunotherapy with antivenom is also ineffective against dermonecrosis. These local effects eventually end up as sequelae. There is also a global shortage of toxins-targeted therapeutics attributed to inadequate knowledge of the actual molecular mechanisms of cytotoxicity. This chapter discusses the characterization of secretory phenotypes of dermonecrosis as an advanced tool to indicate its severity and pathogenesis in envenomation. Altogether, the secretory phenotypes of envenomed cells and tissues represent the precise characteristics of dermonecrosis caused by venom toxins.
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Zeng L, Hou J, Ge C, Li Y, Gao J, Zhang C, Huang P, Du J, Mo Z, Liu Y, Zeng Z. Clinical study of anti-snake venom blockade in the treatment of local tissue necrosis caused by Chinese cobra (Naja atra) bites. PLoS Negl Trop Dis 2022; 16:e0010997. [PMID: 36525460 PMCID: PMC9803274 DOI: 10.1371/journal.pntd.0010997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 12/30/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE This study aimed to evaluate the clinical therapeutic efficacy of anti-snake venom serum blockade in treating local tissue necrosis caused by Chinese cobra (Naja atra) bites. METHODS Patients bitten by a Chinese cobra (Naja atra) (n = 50) that met the inclusion criteria were randomly divided into two groups: the experimental group (n = 25) and the control group (n = 25). The experimental group received regular as well as anti-snake venom serum blocking treatment, whereas regular treatment plus chymotrypsin blocking therapy was given to the control group. The necrotic volumes around snake wounds in these groups were detected on the first, third and seventh days. On the third day of treatment, some local tissues in the wounds were randomly selected for pathological biopsy, and the necrosis volume of the local tissue was observed. Furthermore, the amount of time required for wound healing was recorded. RESULTS On the third and seventh days post-treatment, the necrotic volume of the wound of the experimental group was much smaller than that of the control group, and the experimental group's wound healing time was shorter than that of the control group (all p < 0.05). Moreover, the pathological biopsies taken from the control group showed nuclear pyknosis, fragmentation, sparse nuclear density, and blurred edges, and the degree of necrosis was much higher than that of the experimental group. CONCLUSIONS Anti-snake venom blocking therapy is a new and improved therapy with good clinical effect on local tissue necrosis caused by Chinese cobra bites; moreover, it is superior to conventional chymotrypsin blocking therapy in the treatment of cobra bites. It can better neutralize and prevent the spread of the toxin, reduce tissue necrosis, and shorten the course of the disease by promoting healing of the wound. Furthermore, this treatment plan is also applicable to wound necrosis caused by other snake toxins, such as tissue necrosis caused by elapidae and viper families. CLINICAL TRIAL REGISTRATION This trial is registered in the Chinese Clinical Trial Registry, a primary registry of International Clinical Trial Registry Platform, World Health Organization (Registration No. ChiCTR2200059070; trial URL:http://www.chictr.org.cn/edit.aspx?pid=134353&htm=4).
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Affiliation(s)
- Linsheng Zeng
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Jingjing Hou
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Cuihong Ge
- Guangzhou University of Chinese Medicine, Guangzhou Panyu Central Hospital,Guangzhou,China
| | - Yanjun Li
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Jianhua Gao
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Congcong Zhang
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Peiying Huang
- The Second Clinical Medical School of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiayu Du
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Zhizhun Mo
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Yuxiang Liu
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- * E-mail: (YL); (ZZ)
| | - Zhongyi Zeng
- Department of Emergency, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- * E-mail: (YL); (ZZ)
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7
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Kalita B, Utkin YN, Mukherjee AK. Current Insights in the Mechanisms of Cobra Venom Cytotoxins and Their Complexes in Inducing Toxicity: Implications in Antivenom Therapy. Toxins (Basel) 2022; 14:toxins14120839. [PMID: 36548736 PMCID: PMC9780984 DOI: 10.3390/toxins14120839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/02/2022] Open
Abstract
Cytotoxins (CTXs), an essential class of the non-enzymatic three-finger toxin family, are ubiquitously present in cobra venoms. These low-molecular-mass toxins, contributing to about 40 to 60% of the cobra venom proteome, play a significant role in cobra venom-induced toxicity, more prominently in dermonecrosis. Structurally, CTXs contain the conserved three-finger hydrophobic loops; however, they also exhibit a certain degree of structural diversity that dictates their biological activities. In their mechanism, CTXs mediate toxicity by affecting cell membrane structures and membrane-bound proteins and activating apoptotic and necrotic cell death pathways. Notably, some CTXs are also responsible for depolarizing neurons and heart muscle membranes, thereby contributing to the cardiac failure frequently observed in cobra-envenomed victims. Consequently, they are also known as cardiotoxins (CdTx). Studies have shown that cobra venom CTXs form cognate complexes with other components that potentiate the toxic effects of the venom's individual component. This review focuses on the pharmacological mechanism of cobra venom CTXs and their complexes, highlighting their significance in cobra venom-induced pathophysiology and toxicity. Furthermore, the potency of commercial antivenoms in reversing the adverse effects of cobra venom CTXs and their complexes in envenomed victims has also been discussed.
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Affiliation(s)
- Bhargab Kalita
- Amrita School of Nanosciences and Molecular Medicine, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - Yuri N. Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
| | - Ashis K. Mukherjee
- Institute of Advanced Study in Science and Technology, Guwahati 781035, India
- Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, India
- Correspondence:
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Hiu JJ, Yap MKK. The myth of cobra venom cytotoxin: More than just direct cytolytic actions. Toxicon X 2022; 14:100123. [PMID: 35434602 PMCID: PMC9011113 DOI: 10.1016/j.toxcx.2022.100123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/03/2022] [Accepted: 03/31/2022] [Indexed: 12/26/2022] Open
Abstract
Cobra venom cytotoxin (CTX) is a non-enzymatic three-finger toxin that constitutes 40-60% of cobra venom. Thus, it plays an important role in the pathophysiology of cobra envenomation, especially in local dermonecrosis. The three-finger hydrophobic loops of CTX determine the cytotoxicity. Nevertheless, the actual mechanisms of cytotoxicity are not fully elucidated as they involve not only cytolytic actions but also intracellular signalling-mediated cell death pathways. Furthermore, the possible transition cell death pattern remains to be explored. The actual molecular mechanisms require further studies to unveil the relationship between different CTXs from different cobra species and cell types which may result in differential cell death patterns. Here, we discuss the biophysical interaction of CTX with the cell membrane involving four binding modes: electrostatic interaction, hydrophobic partitioning, isotropic phase, and oligomerisation. Oligomerisation of CTX causes pore formation in the membrane lipid bilayer. Additionally, the CTX-induced apoptotic pathway can be executed via death receptor-mediated extrinsic pathways and mitochondrial-mediated intrinsic pathways. We also discuss lysosomal-mediated necrosis and the occurrence of necroptosis following CTX action. Collectively, we provided an insight into concentration-dependent transition of cell death pattern which involves different mechanistic actions. This contributes a new direction for further investigation of cytotoxic pathways activated by the CTXs for future development of biotherapeutics targeting pathological effects caused by CTX.
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Affiliation(s)
- Jia Jin Hiu
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Michelle Khai Khun Yap
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia.,Tropical Medicine and Biology Multidisciplinary Platform, Monash University Malaysia, Bandar Sunway, Malaysia
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Naja atra Cardiotoxin 1 Induces the FasL/Fas Death Pathway in Human Leukemia Cells. Cells 2021; 10:cells10082073. [PMID: 34440842 PMCID: PMC8394927 DOI: 10.3390/cells10082073] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/06/2021] [Accepted: 08/10/2021] [Indexed: 12/30/2022] Open
Abstract
This study aimed to investigate the mechanistic pathway of Naja atra (Taiwan cobra) cardiotoxin 1 (CTX1)-induced death of leukemia cell lines U937 and HL-60. CTX1 increased cytoplasmic Ca2+ and reactive oxygen species (ROS) production, leading to the death of U937 cells. It was found that Ca2+-induced NOX4 upregulation promoted ROS-mediated p38 MAPK phosphorylation, which consequently induced c-Jun and ATF-2 phosphorylation. Using siRNA knockdown, activated c-Jun and ATF-2 were demonstrated to regulate the expression of Fas and FasL, respectively. Suppression of Ca2+-mediated NOX4 expression or ROS-mediated p38 MAPK activation increased the survival of U937 cells exposed to CTX1. FADD depletion abolished CTX1-induced cell death, caspase-8 activation, and t-Bid production, supporting the correlation between the Fas death pathway and CTX1-mediated cytotoxicity. Among the tested N. atra CTX isotoxins, only CTX1 induced Fas and FasL expression. Chemical modification studies revealed that intact Met residues were essential for the activity of CTX1 to upregulate Fas and FasL expression. Taken together, the data in this study indicate that CTX1 induces c-Jun-mediated Fas and ATF-2-mediated FasL transcription by the Ca2+/NOX4/ROS/p38 MAPK axis, thereby activating the Fas death pathway in U937 cells. Furthermore, CTX1 activates Fas/FasL death signaling in the leukemia cell line HL-60.
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Hiu JJ, Yap MKK. The effects of Naja sumatrana venom cytotoxin, sumaCTX on alteration of the secretome in MCF-7 breast cancer cells following membrane permeabilization. Int J Biol Macromol 2021; 184:776-786. [PMID: 34174307 DOI: 10.1016/j.ijbiomac.2021.06.145] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/21/2021] [Accepted: 06/21/2021] [Indexed: 12/24/2022]
Abstract
Naja sumatrana venom cytotoxin (sumaCTX) is a basic protein which belongs to three-finger toxin family. It has been shown to induce caspase-dependent, mitochondrial-mediated apoptosis in MCF-7 cells at lower concentrations. This study aimed to investigate the alteration of secretome in MCF-7 cells following membrane permeabilization by high concentrations of sumaCTX, using label-free quantitative (LFQ) approach. The degree of membrane permeabilization of sumaCTX was determined by lactate dehydrogenase (LDH) assay and calcein-propidium iodide (PI) assays. LDH and calcein-PI assays revealed time-dependent membrane permeabilization within a narrow concentration range. However, as toxin concentrations increased, prolonged exposure of MCF-7 cells to sumaCTX did not promote the progression of membrane permeabilization. The secretome analyses showed that membrane permeabilization was an event preceding the release of intracellular proteins. Bioinformatics analyses of the LFQ secretome revealed the presence of 105 significantly distinguished proteins involved in metabolism, structural supports, inflammatory responses, and necroptosis in MCF-7 cells treated with 29.8 μg/mL of sumaCTX. Necroptosis was presumably an initial stress response in MCF-7 cells when exposed to high sumaCTX concentration. Collectively, sumaCTX-induced the loss of membrane integrity in a concentration-dependent manner, whereby the cell death pattern of MCF-7 cells transformed from apoptosis to necroptosis with increasing toxin concentrations.
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Affiliation(s)
- Jia Jin Hiu
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia.
| | - Michelle Khai Khun Yap
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia; Tropical Medicine and Biology Multidisciplinary Platform, Monash University Malaysia, Bandar Sunway, Malaysia.
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Giribaldi J, Smith JJ, Schroeder CI. Recent developments in animal venom peptide nanotherapeutics with improved selectivity for cancer cells. Biotechnol Adv 2021; 50:107769. [PMID: 33989705 DOI: 10.1016/j.biotechadv.2021.107769] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/06/2021] [Accepted: 05/08/2021] [Indexed: 02/07/2023]
Abstract
Animal venoms are a rich source of bioactive peptides that efficiently modulate key receptors and ion channels involved in cellular excitability to rapidly neutralize their prey or predators. As such, they have been a wellspring of highly useful pharmacological tools for decades. Besides targeting ion channels, some venom peptides exhibit strong cytotoxic activity and preferentially affect cancer over healthy cells. This is unlikely to be driven by an evolutionary impetus, and differences in tumor cells and the tumor microenvironment are probably behind the serendipitous selectivity shown by some venom peptides. However, strategies such as bioconjugation and nanotechnologies are showing potential to improve their selectivity and potency, thereby paving the way to efficiently harness new anticancer mechanisms offered by venom peptides. This review aims to highlight advances in nano- and chemotherapeutic tools and prospective anti-cancer drug leads derived from animal venom peptides.
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Affiliation(s)
- Julien Giribaldi
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Jennifer J Smith
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Christina I Schroeder
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
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12
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Konshina AG, Dubovskii PV, Efremov RG. Stepwise Insertion of Cobra Cardiotoxin CT2 into a Lipid Bilayer Occurs as an Interplay of Protein and Membrane "Dynamic Molecular Portraits". J Chem Inf Model 2020; 61:385-399. [PMID: 33382618 DOI: 10.1021/acs.jcim.0c01137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
For many peripheral membrane-binding polypeptides(MBPs), especially β-structural ones, the precise molecular mechanisms of membrane insertion remain unclear. In most cases, only the terminal water-soluble and membrane-bound states have been elucidated, whereas potential functionally important intermediate stages are still not understood in sufficient detail. In this study, we present one of the first successful attempts to describe step-by-step embedding of the MBP cardiotoxin 2 (CT2) from cobra Naja oxiana venom into a lipid bilayer at the atomistic level. CT2 possesses a highly conservative and rigid β-structured three-finger fold shared by many other exogenous and endogenous proteins performing a wide variety of functions. The incorporation of CT2 into the lipid bilayer was analyzed via a 2 μs all-atom molecular dynamics (MD) simulation without restraints. This process was shown to occur over a number of distinct steps, while the geometry of initial membrane attachment drastically differs from that of the final equilibrated state. In the latter one, the hydrophobic platform ("bottom") formed by the tips of the three loops is deeply buried into the lipid bilayer. This agrees well with the NMR data obtained earlier for CT2 in detergent micelles. However, the bottom is too bulky to insert itself into the membrane at once. Instead, the gradual immersion of CT2 initiated by the loop-1 was observed. This initial binding stage was also demonstrated in a series of MD runs with varying starting orientations of the toxin with respect to the bilayer surface. Apart from the nonspecific long-range electrostatic attraction and hydrophobic match/mismatch factor, several specific lipid-binding sites were identified in CT2. They were shown to promote membrane insertion by engaging in strong interactions with lipid head groups, fine-tuning the toxin-membrane accommodation. We therefore propose that the toxin insertion relies on the interplay of nonspecific and specific interactions, which are determined by the "dynamic molecular portraits" of the two players, the protein and the membrane. The proposed model does not require protein oligomerization for membrane insertion and can be further employed to design MBPs with predetermined properties with regard to particular membrane targets.
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Affiliation(s)
- Anastasia G Konshina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow 117997, Russia
| | - Peter V Dubovskii
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow 117997, Russia
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow 117997, Russia.,National Research University Higher School of Economics, 20 Myasnitskaya str., Moscow 101000, Russia.,Research Center for Molecular Mechanisms of Aging and Age-related Diseases, Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141700, Russia
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13
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Chong HP, Tan KY, Tan CH. Cytotoxicity of Snake Venoms and Cytotoxins From Two Southeast Asian Cobras ( Naja sumatrana, Naja kaouthia): Exploration of Anticancer Potential, Selectivity, and Cell Death Mechanism. Front Mol Biosci 2020; 7:583587. [PMID: 33263003 PMCID: PMC7686564 DOI: 10.3389/fmolb.2020.583587] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/25/2020] [Indexed: 01/09/2023] Open
Abstract
Venoms of cobras (Naja spp.) contain high abundances of cytotoxins, which contribute to tissue necrosis in cobra envenomation. The tissue-necrotizing activity of cobra cytotoxins, nevertheless, indicates anticancer potentials. This study set to explore the anticancer properties of the venoms and cytotoxins from Naja sumatrana (equatorial spitting cobra) and Naja kaouthia (monocled cobra), two highly venomous species in Southeast Asia. The cytotoxicity, selectivity, and cell death mechanisms of their venoms and cytotoxins (NS-CTX from N. sumatrana: NS-CTX; N. kaouthia: NK-CTX) were elucidated in human lung (A549), prostate (PC-3), and breast (MCF-7) cancer cell lines. Cytotoxins were purified through a sequential fractionation approach using cation-exchange chromatography, followed by C18 reverse-phase high-performance liquid chromatography (HPLC) to homogeneity validated with sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and identified by liquid chromatography-tandem mass spectrometry (LCMS/MS). The cobra venoms and their respective cytotoxins exhibited concentration-dependent growth inhibitory effects in all cell lines tested, with the cytotoxins being more potent compared to the corresponding whole venoms. NS-CTX and NK-CTX are, respectively, P-type and S-type isoforms of cytotoxin, based on the amino acid sequences as per LCMS/MS analysis. Both cytotoxins exhibited differential cytotoxic effects in the cell lines tested, with NS-CTX (P-type cytotoxin) being significantly more potent in inhibiting the growth of the cancer cells. Both cytotoxins demonstrated promising selectivity only for the A549 lung cancer cell line (selectivity index = 2.17 and 2.26, respectively) but not in prostate (PC-3) and breast (MCF-7) cancer cell lines (selectivity index < 1). Flow cytometry revealed that the A549 lung cancer cells treated with NS-CTX and NK-CTX underwent necrosis predominantly. Meanwhile, the cytotoxins induced mainly caspase-independent late apoptosis in the prostate (PC-3) and breast (MCF-7) cancer cells lines but lacked selectivity. The findings revealed the limitations and challenges that could be faced during the development of new cancer therapy from cobra cytotoxins, notwithstanding their potent anticancer effects. Further studies should aim to overcome these impediments to unleash the anticancer potentials of the cytotoxins.
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Affiliation(s)
- Ho Phin Chong
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kae Yi Tan
- Protein and Interactomics Lab, Department of Molecular Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Choo Hock Tan
- Venom Research and Toxicology Lab, Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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14
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Teoh SQ, Yap MKK. Naja sumatrana venom cytotoxin, sumaCTX exhibits concentration-dependent cytotoxicity via caspase-activated mitochondrial-mediated apoptosis without transitioning to necrosis. TOXIN REV 2020. [DOI: 10.1080/15569543.2020.1799408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Shun Qi Teoh
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Michelle Khai Khun Yap
- School of Science, Monash University Malaysia, Bandar Sunway, Malaysia
- Tropical Medicine and Biology Platform, Monash University Malaysia, Bandar Sunway, Malaysia
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15
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Li F, Shrivastava IH, Hanlon P, Dagda RK, Gasanoff ES. Molecular Mechanism by which Cobra Venom Cardiotoxins Interact with the Outer Mitochondrial Membrane. Toxins (Basel) 2020; 12:E425. [PMID: 32605112 PMCID: PMC7404710 DOI: 10.3390/toxins12070425] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 12/29/2022] Open
Abstract
Cardiotoxin CTII from Najaoxiana cobra venom translocates to the intermembrane space (IMS) of mitochondria to disrupt the structure and function of the inner mitochondrial membrane. At low concentrations, CTII facilitates ATP-synthase activity, presumably via the formation of non-bilayer, immobilized phospholipids that are critical in modulating ATP-synthase activity. In this study, we investigated the effects of another cardiotoxin CTI from Najaoxiana cobra venom on the structure of mitochondrial membranes and on mitochondrial-derived ATP synthesis. By employing robust biophysical methods including 31P-NMR and 1H-NMR spectroscopy, we analyzed the effects of CTI and CTII on phospholipid packing and dynamics in model phosphatidylcholine (PC) membranes enriched with 2.5 and 5.0 mol% of cardiolipin (CL), a phospholipid composition that mimics that in the outer mitochondrial membrane (OMM). These experiments revealed that CTII converted a higher percentage of bilayer phospholipids to a non-bilayer and immobilized state and both cardiotoxins utilized CL and PC molecules to form non-bilayer structures. Furthermore, in order to gain further understanding on how cardiotoxins bind to mitochondrial membranes, we employed molecular dynamics (MD) and molecular docking simulations to investigate the molecular mechanisms by which CTII and CTI interactively bind with an in silico phospholipid membrane that models the composition similar to the OMM. In brief, MD studies suggest that CTII utilized the N-terminal region to embed the phospholipid bilayer more avidly in a horizontal orientation with respect to the lipid bilayer and thereby penetrate at a faster rate compared with CTI. Molecular dynamics along with the Autodock studies identified critical amino acid residues on the molecular surfaces of CTII and CTI that facilitated the long-range and short-range interactions of cardiotoxins with CL and PC. Based on our compiled data and our published findings, we provide a conceptual model that explains a molecular mechanism by which snake venom cardiotoxins, including CTI and CTII, interact with mitochondrial membranes to alter the mitochondrial membrane structure to either upregulate ATP-synthase activity or disrupt mitochondrial function.
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Affiliation(s)
- Feng Li
- STEM Program, Science Department, Chaoyang KaiWen Academy, Yard 46, 3rd Baoquan Street, Chaoyang District, Beijing 100018, China; (F.L.); (P.H.); (E.S.G.)
| | - Indira H. Shrivastava
- Department of Computational and System Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA;
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Paul Hanlon
- STEM Program, Science Department, Chaoyang KaiWen Academy, Yard 46, 3rd Baoquan Street, Chaoyang District, Beijing 100018, China; (F.L.); (P.H.); (E.S.G.)
| | - Ruben K. Dagda
- Reno School of Medicine, Department of Pharmacology, University of Nevada, Reno, NV 89557, USA
| | - Edward S. Gasanoff
- STEM Program, Science Department, Chaoyang KaiWen Academy, Yard 46, 3rd Baoquan Street, Chaoyang District, Beijing 100018, China; (F.L.); (P.H.); (E.S.G.)
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16
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Guo R, Yu Q, Liong EC, Fung ML, Tipoe GL. Cathepsin-B dependent autophagy ameliorates steatoheaptitis in chronic exercise rats. Histol Histopathol 2020; 35:833-847. [PMID: 31975365 DOI: 10.14670/hh-18-204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE This study aimed to investigate the role of cathepsin B dependent autophagy induced by chronic aerobic exercise on a high-fat diet (HFD)-induced nonalcoholic steatohepatitis (NASH) in rats. METHODS Healthy female (Sprague-Dawley) SD rats (8-10 weeks old; 180g-200g; n=6 per group) were divided into: (1) control group; (2) HFD group; (3) Exercise group; (4) HFD + exercise group. Rats were fed with a normal chow or an HFD for 12 weeks. Rats with exercise ran on a rotarod for 30 min per day from weeks 9-12. RESULTS Exercise training significantly (1) upregulated the levels of autophagy markers Beclin1, ATG5 and LC3II partly through inhibiting the p-AKT/mTOR pathway; (2) ameliorated HFD-mediated accumulation of fat mass by upregulating β-oxidation regulator PPAR-α and downregulating fatty acid synthesis marker SREBP-1c via lipophagy; (3) diminished the HFD-induced hepatic pro-inflammatory mediators TNF-α and IL-1β via NF-κB inactivation; (4) decreased the NASH-induced hepatic apoptotic marker caspase-3 activation caused by the upstream oxidative stress and by cytochrome P450 2E1 (CYP2E1); (5) mitigated the HFD-mediated lysosomal membrane permeabilisation and cathepsin B release partly via the reduction of reactive oxygen species (ROS). CONCLUSIONS Chronic aerobic exercise reduces oxidative stress/ROS and ROS may cause lysosomal membrane destabilisation and disrupts the autophagic process. The beneficial effect of chronic exercise may further inhibit the process of lysosome membrane permeabilisation and facilitate lysosome fusion with autophagosomes to trigger autophagy. This process may possibly contribute to the inhibition of cathepsin B released into cytosol which further reduces inflammation and mitochondrial-dependent apoptosis.
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Affiliation(s)
- Rui Guo
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R
| | - Qian Yu
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R
| | - Emily C Liong
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R
| | - Man Lung Fung
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R.,Brain Hormone Healthy Aging Centre, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R
| | - George L Tipoe
- Brain Hormone Healthy Aging Centre, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R.,School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R.
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17
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Chiou JT, Shi YJ, Wang LJ, Huang CH, Lee YC, Chang LS. Naja atra Cardiotoxin 3 Elicits Autophagy and Apoptosis in U937 Human Leukemia Cells through the Ca 2+/PP2A/AMPK Axis. Toxins (Basel) 2019; 11:toxins11090527. [PMID: 31547294 PMCID: PMC6784133 DOI: 10.3390/toxins11090527] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 09/04/2019] [Accepted: 09/10/2019] [Indexed: 12/22/2022] Open
Abstract
Cardiotoxins (CTXs) are suggested to exert their cytotoxicity through cell membrane damage. Other studies show that penetration of CTXs into cells elicits mitochondrial fragmentation or lysosome disruption, leading to cell death. Considering the role of AMPK-activated protein kinase (AMPK) in mitochondrial biogenesis and lysosomal biogenesis, we aimed to investigate whether the AMPK-mediated pathway modulated Naja atra (Taiwan cobra) CTX3 cytotoxicity in U937 human leukemia cells. Our results showed that CTX3 induced autophagy and apoptosis in U937 cells, whereas autophagic inhibitors suppressed CTX3-induced apoptosis. CTX3 treatment elicited Ca2+-dependent degradation of the protein phosphatase 2A (PP2A) catalytic subunit (PP2Acα) and phosphorylation of AMPKα. Overexpression of PP2Acα mitigated the CTX3-induced AMPKα phosphorylation. CTX3-induced autophagy was via AMPK-mediated suppression of the Akt/mTOR pathway. Removal of Ca2+ or suppression of AMPKα phosphorylation inhibited the CTX3-induced cell death. CTX3 was unable to induce autophagy and apoptosis in U937 cells expressing constitutively active Akt. Met-modified CTX3 retained its membrane-perturbing activity, however, it did not induce AMPK activation and death of U937 cells. These results conclusively indicate that CTX3 induces autophagy and apoptosis in U937 cells via the Ca2+/PP2A/AMPK axis, and suggest that the membrane-perturbing activity of CTX3 is not crucial for the cell death signaling pathway induction.
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Affiliation(s)
- Jing-Ting Chiou
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Yi-Jun Shi
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Liang-Jun Wang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Chia-Hui Huang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Yuan-Chin Lee
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
| | - Long-Sen Chang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan.
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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18
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Cytotoxin 1 from Naja atra Cantor venom induced necroptosis of leukemia cells. Toxicon 2019; 165:110-115. [DOI: 10.1016/j.toxicon.2019.04.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 04/13/2019] [Accepted: 04/22/2019] [Indexed: 01/19/2023]
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19
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Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function. Toxins (Basel) 2019; 11:toxins11030152. [PMID: 30857180 PMCID: PMC6468758 DOI: 10.3390/toxins11030152] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/01/2019] [Accepted: 03/05/2019] [Indexed: 01/07/2023] Open
Abstract
Cobra venom cardiotoxins (CVCs) can translocate to mitochondria to promote apoptosis by eliciting mitochondrial dysfunction. However, the molecular mechanism(s) by which CVCs are selectively targeted to the mitochondrion to disrupt mitochondrial function remains to be elucidated. By studying cardiotoxin from Naja mossambica mossambica cobra (cardiotoxin VII4), a basic three-fingered S-type cardiotoxin, we hypothesized that cardiotoxin VII4 binds to cardiolipin (CL) in mitochondria to alter mitochondrial structure/function and promote neurotoxicity. By performing confocal analysis, we observed that red-fluorescently tagged cardiotoxin rapidly translocates to mitochondria in mouse primary cortical neurons and in human SH-SY5Y neuroblastoma cells to promote aberrant mitochondrial fragmentation, a decline in oxidative phosphorylation, and decreased energy production. In addition, by employing electron paramagnetic resonance (EPR) and protein nuclear magnetic resonance (1H-NMR) spectroscopy and phosphorescence quenching of erythrosine in model membranes, our compiled biophysical data show that cardiotoxin VII4 binds to anionic CL, but not to zwitterionic phosphatidylcholine (PC), to increase the permeability and formation of non-bilayer structures in CL-enriched membranes that biochemically mimic the outer and inner mitochondrial membranes. Finally, molecular dynamics simulations and in silico docking studies identified CL binding sites in cardiotoxin VII4 and revealed a molecular mechanism by which cardiotoxin VII4 interacts with CL and PC to bind and penetrate mitochondrial membranes.
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20
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Xia C, Luan T, Chen Y, Yan R, Yuan S, Yang D, Wang H. MT-12 inhibits the growth and metastasis of bladder cancer cells via suppressing tumor angiogenesis in vivo and in vitro. Transl Cancer Res 2019; 8:120-129. [PMID: 35116741 PMCID: PMC8798266 DOI: 10.21037/tcr.2019.01.12] [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: 08/24/2018] [Accepted: 12/27/2018] [Indexed: 11/28/2022]
Abstract
Background Cobra venom membrane toxin (MT) has been defined as a major subset of cobra venom having cardiac toxicity and anticancer activity properties. In our previous study, cobra venom membrane toxin 12 (MT-12), isolated from the snake venom of Chinese Naja naja atra, was confirmed to selectively suppress the proliferation and invasion of the bladder cancer (BC) cell line EJ. However, the results have never been confirmed in other bladder cell lines, and the underlying mechanism by which MT-12 inhibits BC is still unknown. Thus, in this study, the effect of MT-12 on the proliferation, adhesion, and invasion of BC cells was explored in vitro and in vivo. As tumor angiogenesis is a prerequisite for tumor growth and metastasis, the factors involved, such as matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1), were tested in our study. Methods Using RT4 and T24 cells for experiments, CCK-8 assays were used to determine cell proliferation. Annexin V-FITC/PI was used to determine cell apoptosis status. Wound-healing assays were used to determine cell invasion. Cell adhesion experiments were used to determine cell adhesion. Gelatin zymography was used to determine the enzymatic activity of MMP-9 and MMP-2. RT-PCR, ELISA, and immunohistochemistry were used to determine the expression of VEGF, ICAM-1, and VCAM-1. Results MT-12 inhibited proliferation, invasion, and adhesion and promoted cell apoptosis in RT4 and T24 cells; this anticancer effect was concentration-dependent. In the BC xenograft mouse model, the results revealed that MT-12 might decrease tumor growth and weight. MT-12 was shown to have an inhibitory effect on MMP-9 activation and the expression of VEGF and ICAM-1 in BC cells in vitro and in vivo. Conclusions The results of the present study, suggest that MT-12 could effectively inhibit BC cell growth and metastasis via inhibition of tumor angiogenesis. As a result, MT-12 may become a novel drug for BC.
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Affiliation(s)
- Chengxing Xia
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Ting Luan
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Yan Chen
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Ruping Yan
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Shunhui Yuan
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Delin Yang
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
| | - Haifeng Wang
- Department of Urology, The Second Affiliated Hospital of Kunming Medical University, Yunnan Institute of Urology, Kunming 650101, China
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Abstract
Naja ashei is an African spitting cobra species closely related to N. mossambica and N. nigricollis. It is known that the venom of N. ashei, like that of other African spitting cobras, mainly has cytotoxic effects, however data about its specific protein composition are not yet available. Thus, an attempt was made to determine the venom proteome of N. ashei with the use of 2-D electrophoresis and MALDI ToF/ToF (Matrix-Assisted Laser Desorption/Ionization Time of Flight) mass spectrometry techniques. Our investigation revealed that the main components of analysed venom are 3FTxs (Three-Finger Toxins) and PLA₂s (Phospholipases A₂). Additionally the presence of cysteine-rich venom proteins, 5'-nucleotidase and metalloproteinases has also been confirmed. The most interesting fact derived from this study is that the venom of N. ashei includes proteins not described previously in other African spitting cobras-cobra venom factor and venom nerve growth factor. To our knowledge, there are currently no other reports concerning this venom composition and we believe that our results will significantly increase interest in research of this species.
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Affiliation(s)
- Konrad Kamil Hus
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstańców Warszawy 6, 35-959 Rzeszow, Poland.
| | - Justyna Buczkowicz
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstańców Warszawy 6, 35-959 Rzeszow, Poland.
| | - Vladimír Petrilla
- Department of Physiology, University of Veterinary Medicine and Pharmacy, Komenského 73, 041 81 Kosice, Slovakia.
- Zoological Department, Zoological Garden Košice, Široká 31, 040 06 Košice-Kavečany, Slovakia.
| | - Monika Petrillová
- Department of General Education Subjects, University of Veterinary Medicine and Pharmacy, Komenského 73, 041 81 Kosice, Slovakia.
| | - Andrzej Łyskowski
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstańców Warszawy 6, 35-959 Rzeszow, Poland.
| | - Jaroslav Legáth
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstańców Warszawy 6, 35-959 Rzeszow, Poland.
- Department of Pharmacology and Toxicology, University of Veterinary Medicine and Pharmacy, Komenského 73, 041 81 Kosice, Slovakia.
| | - Aleksandra Bocian
- Department of Biotechnology and Bioinformatics, Faculty of Chemistry, Rzeszow University of Technology, Powstańców Warszawy 6, 35-959 Rzeszow, Poland.
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22
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Affiliation(s)
- Hassan M. Akef
- National Organization for Research and Control of Biologicals (NORCB), Giza, Egypt
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23
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Bhowmik T, Saha PP, Sarkar A, Gomes A. Evaluation of cytotoxicity of a purified venom protein from Naja kaouthia (NKCT1) using gold nanoparticles for targeted delivery to cancer cell. Chem Biol Interact 2016; 261:35-49. [PMID: 27836789 DOI: 10.1016/j.cbi.2016.11.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/20/2016] [Accepted: 11/07/2016] [Indexed: 11/18/2022]
Abstract
In our earlier report, gold nanoparticle (GNP) and snake venom protein toxin NKCT1 were conjugated and primary characteristics were done. In this communication, further characteristics of GNP-NKCT1 were done with TGA, BET, Zeta potential, ICP-MS, FTIR, XPS, and in vitro release kinetics for its physicochemical, molecular nature and bonding. TGA and ICP-MS showed that the number of conjugation was 40 ± 5 to 90 ± 8 NKCT1 per gold nanoparticles. FTIR and XPS corresponding to (CO), (NH), (SS) reformulated the conjugation of GNP with NKCT1. The efficacy of GNP-NKCT1 on cancer cells were analyzed by MTT assay which demonstrated superior cytotoxic effects as compared to native NKCT1. IC50 dose of GNP-NKCT1 was less than 4 μg/ml in cancer cell lines, whereas in case of NKCT1 it was average 8 μg/ml. Twice dose of IC50 of GNP-NKCT1 even showed less toxicity compared to unconjugated NKCT1, towards normal epithelial or fibroblast cell and also in peripheral blood mononuclear lymphocytes. Flow cytometry analysis revealed that percentage of apoptotic C6 cells was much higher in GNP-NKCT1 treatment (54.58%) than that of NKCT1 treatment (26.79%). Flow cytometric analysis of cell cycle using GNP-NKCT1 on C6 cancer cells revealed that it arrested the cell cycle at Go/G1 phases. In diethylnitrosamine (DEN) induced in vivo hepatocarcinoma mice, the activities of hepatic enzymes- aspartate transaminase (AST) and alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and activities of antioxidant enzymes- superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx) were restored by GNP-NKCT1. This study indicated the capability of gold nanoparticles in enhancing the cancer cell uptake of NKCT1 and also suggested that GNP-NKCT1 might be a good source of anti-carcinoma or anti-sarcoma targeted agent.
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Affiliation(s)
- Tanmoy Bhowmik
- Laboratory of Toxinology & Experimental Pharmacodynamics, Department of Physiology, University of Calcutta, 92, APC Road, Kolkata, 700 009, India
| | - Partha Pratim Saha
- Laboratory of Toxinology & Experimental Pharmacodynamics, Department of Physiology, University of Calcutta, 92, APC Road, Kolkata, 700 009, India
| | - Amrita Sarkar
- Laboratory of Toxinology & Experimental Pharmacodynamics, Department of Physiology, University of Calcutta, 92, APC Road, Kolkata, 700 009, India
| | - Antony Gomes
- Laboratory of Toxinology & Experimental Pharmacodynamics, Department of Physiology, University of Calcutta, 92, APC Road, Kolkata, 700 009, India.
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24
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Shulepko MA, Lyukmanova EN, Shenkarev ZO, Dubovskii PV, Astapova MV, Feofanov AV, Arseniev AS, Utkin YN, Kirpichnikov MP, Dolgikh DA. Towards universal approach for bacterial production of three-finger Ly6/uPAR proteins: Case study of cytotoxin I from cobra N. oxiana. Protein Expr Purif 2016; 130:13-20. [PMID: 27702601 DOI: 10.1016/j.pep.2016.09.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 01/26/2023]
Abstract
Cytotoxins or cardiotoxins is a group of polycationic toxins from cobra venom belonging to the 'three-finger' protein superfamily (Ly6/uPAR family) which includes small β-structural proteins (60-90 residues) with high disulfide bond content (4-5 disulfides). Due to a high cytotoxic activity for cancer cells, cytotoxins are considered as potential anticancer agents. Development of the high-throughput production methods is required for the prospective applications of cytotoxins. Here, efficient approach for bacterial production of recombinant analogue of cytotoxin I from N. oxiana containing additional N-terminal Met-residue (rCTX1) was developed. rCTX1 was produced in the form of E. coli inclusion bodies. Refolding in optimized conditions provided ∼6 mg of correctly folded protein from 1 L of bacterial culture. Cytotoxicity of rCTX1 for C6 rat glioma cells was found to be similar to the activity of wild type CTX1. The milligram quantities of 13C,15N-labeled rCTX1 were obtained. NMR study confirmed the similarity of the spatial structures of recombinant and wild-type toxins. Additional Met residue does not perturb the overall structure of the three-finger core. The analysis of available data for different Ly6/uPAR proteins of snake and human origin revealed that efficiency of their folding in vitro is correlated with the number of proline residues in the third loop and the surface area of hydrophobic residues buried within the protein interior. The obtained data indicate that hydrophobic core is important for the folding of proteins with high disulfide bond content. Developed expression method opens new possibilities for structure-function studies of CTX1 and other related three-finger proteins.
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Affiliation(s)
- M A Shulepko
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - E N Lyukmanova
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia.
| | - Z O Shenkarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region, 141700, Russia
| | - P V Dubovskii
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - M V Astapova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - A V Feofanov
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - A S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia; Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, Dolgoprudny, Moscow Region, 141700, Russia
| | - Y N Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - M P Kirpichnikov
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
| | - D A Dolgikh
- Biological Faculty, Lomonosov Moscow State University, 119234, Moscow, Russia; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya Street, 117997, Moscow, Russia
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25
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Mechanism of apoptosis induction in human breast cancer MCF-7 cell by Ruviprase, a small peptide from Daboia russelii russelii venom. Chem Biol Interact 2016; 258:297-304. [PMID: 27613483 DOI: 10.1016/j.cbi.2016.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/23/2016] [Accepted: 09/06/2016] [Indexed: 12/13/2022]
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Chen F, Deng Z, Xiong Z, Zhang B, Yang J, Hu J. A ROS-mediated lysosomal-mitochondrial pathway is induced by ginsenoside Rh2 in hepatoma HepG2 cells. Food Funct 2016; 6:3828-37. [PMID: 26449932 DOI: 10.1039/c5fo00518c] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ginsenoside Rh2 (GRh2), isolated from Panax ginseng C. A. Meyer, has been proven as an anticancer compound both in vitro and in vivo. In the present study, we investigated the role of the lysosomes during the apoptosis of HepG2 cells induced by GRh2. The results showed that GRh2 significantly induced intracellular reactive oxygen species (ROS) generation in the HepG2 cells, which consequently resulted in early lysosomal membrane permeabilization with the release of cathepsin B (Cat B) to the cytosol. Western blot analysis showed that the released Cat B in the cytosol contributed to Bid cleavage. Subsequently mitochondrial damage was observed in the HepG2 cells. Interestingly, when the HepG2 cells were pre-treated with N-Acetyl-L-Cysteine (NAC) for 1 h, which inhibited ROS generation before being exposed to GRh2, the permeabilization of lysosomal membranes and the levels of Cat B in the cytosol were down-regulated. Moreover, mitochondrial damage was alleviated when the HepG2 cells were pre-treated with leupeptin (Leu). From the above results, it could be concluded that GRh2 induced apoptosis of the HepG2 cells through accumulation of ROS and activation of the lysosomal-mitochondrial apoptotic pathway involving the release of Cat B.
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Affiliation(s)
- Fang Chen
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China. and College of Life Science & Food Engineering, Nanchang University, Nanchang, Jiangxi 330047, China
| | - ZeYuan Deng
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China. and College of Life Science & Food Engineering, Nanchang University, Nanchang, Jiangxi 330047, China
| | - ZengXing Xiong
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China. and College of Life Science & Food Engineering, Nanchang University, Nanchang, Jiangxi 330047, China
| | - Bing Zhang
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China.
| | - JianYuan Yang
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China. and College of Pharmaceutical and Life Sciences, Jiujiang University, Jiujiang 332000, China
| | - JiangNing Hu
- State Key Laboratory of Food Science and Technology, Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330047, China. and College of Life Science & Food Engineering, Nanchang University, Nanchang, Jiangxi 330047, China
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Chan YS, Cheung RCF, Xia L, Wong JH, Ng TB, Chan WY. Snake venom toxins: toxicity and medicinal applications. Appl Microbiol Biotechnol 2016; 100:6165-6181. [PMID: 27245678 DOI: 10.1007/s00253-016-7610-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 05/01/2016] [Accepted: 05/03/2016] [Indexed: 11/25/2022]
Abstract
Snake venoms are complex mixtures of small molecules and peptides/proteins, and most of them display certain kinds of bioactivities. They include neurotoxic, cytotoxic, cardiotoxic, myotoxic, and many different enzymatic activities. Snake envenomation is a significant health issue as millions of snakebites are reported annually. A large number of people are injured and die due to snake venom poisoning. However, several fatal snake venom toxins have found potential uses as diagnostic tools, therapeutic agent, or drug leads. In this review, different non-enzymatically active snake venom toxins which have potential therapeutic properties such as antitumor, antimicrobial, anticoagulating, and analgesic activities will be discussed.
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Affiliation(s)
- Yau Sang Chan
- State Key Laboratory of Respiratory Disease for Allergy, School of Medicine, Shenzhen University, Nanhai Ave 3688, 518060, Shenzhen, Guangdong, China
| | - Randy Chi Fai Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Lixin Xia
- State Key Laboratory of Respiratory Disease for Allergy, School of Medicine, Shenzhen University, Nanhai Ave 3688, 518060, Shenzhen, Guangdong, China.
| | - Jack Ho Wong
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Wai Yee Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
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28
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Ebrahim K, Shirazi FH, Mirakabadi AZ, Vatanpour H. Cobra venom cytotoxins; apoptotic or necrotic agents? Toxicon 2015; 108:134-40. [DOI: 10.1016/j.toxicon.2015.09.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/10/2015] [Accepted: 09/15/2015] [Indexed: 11/28/2022]
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Naja naja oxiana Cobra Venom Cytotoxins CTI and CTII Disrupt Mitochondrial Membrane Integrity: Implications for Basic Three-Fingered Cytotoxins. PLoS One 2015; 10:e0129248. [PMID: 26091109 PMCID: PMC4474699 DOI: 10.1371/journal.pone.0129248] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 05/06/2015] [Indexed: 12/21/2022] Open
Abstract
Cobra venom cytotoxins are basic three-fingered, amphipathic, non-enzymatic proteins that constitute a major fraction of cobra venom. While cytotoxins cause mitochondrial dysfunction in different cell types, the mechanisms by which cytotoxins bind to mitochondria remain unknown. We analyzed the abilities of CTI and CTII, S-type and P-type cytotoxins from Naja naja oxiana respectively, to associate with isolated mitochondrial fractions or with model membranes that simulate the mitochondrial lipid environment by using a myriad of biophysical techniques. Phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy data suggest that both cytotoxins bind to isolated mitochondrial fractions and promote the formation of aberrant non-bilayer structures. We then hypothesized that CTI and CTII bind to cardiolipin (CL) to disrupt mitochondrial membranes. Collectively, 31P-NMR, electron paramagnetic resonance (EPR), proton NMR (1H-NMR), deuterium NMR (2H-NMR) spectroscopy, differential scanning calorimetry, and erythrosine phosphorescence assays suggest that CTI and CTII bind to CL to generate non-bilayer structures and promote the permeabilization, dehydration and fusion of large unilamellar phosphatidylcholine (PC) liposomes enriched with CL. On the other hand, CTII but not CTI caused biophysical alterations of large unilamellar PC liposomes enriched with phosphatidylserine (PS). Mechanistically, single molecule docking simulations identified putative CL, PS and PC binding sites in CTI and CTII. While the predicted binding sites for PS and PC share a high number of interactive amino acid residues in CTI and CTII, the CL biding sites in CTII and CTI are more divergent as it contains additional interactive amino acid residues. Overall, our data suggest that cytotoxins physically associate with mitochondrial membranes by binding to CL to disrupt mitochondrial structural integrity.
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Lee SC, Lin CC, Wang CH, Wu PL, Huang HW, Chang CI, Wu WG. Endocytotic routes of cobra cardiotoxins depend on spatial distribution of positively charged and hydrophobic domains to target distinct types of sulfated glycoconjugates on cell surface. J Biol Chem 2014; 289:20170-81. [PMID: 24898246 DOI: 10.1074/jbc.m114.557157] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Cobra cardiotoxins (CTX) are a family of three-fingered basic polypeptides known to interact with diverse targets such as heparan sulfates, sulfatides, and integrins on cell surfaces. After CTX bind to the membrane surface, they are internalized to intracellular space and exert their cytotoxicity via an unknown mechanism. By the combined in vitro kinetic binding, three-dimensional x-ray structure determination, and cell biology studies on the naturally abundant CTX homologues from the Taiwanese cobra, we showed that slight variations on the spatial distribution of positively charged or hydrophobic domains among CTX A2, A3, and A4 could lead to significant changes in their endocytotic pathways and action mechanisms via distinct sulfated glycoconjugate-mediated processes. The intracellular locations of these structurally similar CTX after internalization are shown to vary between the mitochondria and lysosomes via either dynamin2-dependent or -independent processes with distinct membrane cholesterol sensitivity. Evidence is presented to suggest that the shifting between the sulfated glycoconjugates as distinct targets of CTX A2, A3, and A4 might play roles in the co-evolutionary arms race between venomous snake toxins to cope with different membrane repair mechanisms at the cellular levels. The sensitivity of endocytotic routes to the spatial distribution of positively charged or hydrophobic domains may provide an explanation for the diverse endocytosis pathways of other cell-penetrating basic polypeptides.
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Affiliation(s)
- Shao-Chen Lee
- From the School of Medicine, FuJen Catholic University, Xinzhuang District, New Taipei City, 24205, Taiwan
| | - Chien-Chu Lin
- the Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan, the Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Chia-Hui Wang
- the Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Po-Long Wu
- the Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Hsuan-Wei Huang
- the Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Chung-I Chang
- the Institute of Biological Chemistry, Academia Sinica, Taipei, 11529, Taiwan
| | - Wen-guey Wu
- the Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013, Taiwan,
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