1
|
Truong NV, Phan TTT, Hsu TS, Phu Duc P, Lin LY, Wu WG. Action mechanism of snake venom l-amino acid oxidase and its double-edged sword effect on cancer treatment: Role of pannexin 1-mediated interleukin-6 expression. Redox Biol 2023; 64:102791. [PMID: 37385076 DOI: 10.1016/j.redox.2023.102791] [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: 05/02/2023] [Accepted: 06/16/2023] [Indexed: 07/01/2023] Open
Abstract
Snake venom l-amino acid oxidases (svLAAOs) have been recognized as promising candidates for anticancer therapeutics. However, multiple aspects of their catalytic mechanism and the overall responses of cancer cells to these redox enzymes remain ambiguous. Here, we present an analysis of the phylogenetic relationships and active site-related residues among svLAAOs and reveal that the previously proposed critical catalytic residue His 223 is highly conserved in the viperid but not the elapid svLAAO clade. To gain further insight into the action mechanism of the elapid svLAAOs, we purify and characterize the structural, biochemical, and anticancer therapeutic potentials of the Thailand elapid snake Naja kaouthia LAAO (NK-LAAO). We find that NK-LAAO, with Ser 223, exhibits high catalytic activity toward hydrophobic l-amino acid substrates. Moreover, NK-LAAO induces substantial oxidative stress-mediated cytotoxicity with the magnitude relying on both the levels of extracellular hydrogen peroxide (H2O2) and intracellular reactive oxygen species (ROS) generated during the enzymatic redox reactions, but not being influenced by the N-linked glycans on its surface. Unexpectedly, we discover a tolerant mechanism deployed by cancer cells to dampen the anticancer activities of NK-LAAO. NK-LAAO treatment amplifies interleukin (IL)-6 expression via the pannexin 1 (Panx1)-directed intracellular calcium (iCa2+) signaling pathway to confer adaptive and aggressive phenotypes on cancer cells. Accordingly, IL-6 silencing renders cancer cells vulnerable to NK-LAAO-induced oxidative stress together with abrogating NK-LAAO-stimulated metastatic acquisition. Collectively, our study urges caution when using svLAAOs in cancer treatment and identifies the Panx1/iCa2+/IL-6 axis as a therapeutic target for improving the effectiveness of svLAAOs-based anticancer therapies.
Collapse
Affiliation(s)
- Nam V Truong
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC
| | - Trinh T T Phan
- Institute of Molecular and Cellular Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC
| | - Tzu-Sheng Hsu
- Institute of Molecular and Cellular Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC
| | - Phan Phu Duc
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC
| | - Lih-Yuan Lin
- Institute of Molecular and Cellular Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC.
| | - Wen-Guey Wu
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, 300044, Taiwan, ROC.
| |
Collapse
|
2
|
Bernardes CP, Santos NAG, Costa TR, Menaldo DL, Sisti FM, Amstalden MK, Ribeiro DL, Antunes LMG, Sampaio SV, Santos AC. Effects of C-Terminal-Ethyl-Esterification in a Snake-Venom-Based Peptide Against the Neurotoxicity of Acrolein in PC12 Cells. Int J Pept Res Ther 2023. [DOI: 10.1007/s10989-023-10517-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
|
3
|
Liang J, Zhang R, Zhao J, Liu H. Active sites of peptide from Arg-Ser-Ser protect against oxidative stress in HepG2 cells. EFOOD 2021. [DOI: 10.53365/efood.k/143990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Peptide Arg-Ser-Ser (RSS) was derived from Lactobacillus amylolyticus co-incubated with edible <i>Dendrobium aphyllum</i>. Here, we further examined the antioxidative effects of RSS in HepG2 cells subjected to 2,2-azobis(2-methylpropanimidamidine) dihydrochloride-induced oxidative stress. RSS protected cells by eliminating the level of reactive oxygen species (ROS). The protein expression of antioxidant enzymes, Nrf2 and Keap1 determined by western blot, indicated that RSS might maintain cellular homeostasis by directly scavenging free radicals instead of by enzymatic system. Furthermore, quantum chemistry calculations and a characterization of electronic-related properties showed that the highest occupied molecular orbital energy distribution was on arginine residue. Pre-treatment with RSS with the active site methylated resulted in increased ROS levels, thereby verifying that N<sub>2</sub>-H<sub>3</sub> is the active site for antioxidant activity. Our findings provide valuable insights into the antioxidant activity of RSS and a basis for developing antioxidant functional foods.
Collapse
|
4
|
Abdelkafi-Koubaa Z, ELBini-Dhouib I, Souid S, Jebali J, Doghri R, Srairi-Abid N, Essafi-Benkhadir K, Micheau O, Marrakchi N. Pharmacological Investigation of CC-LAAO, an L-Amino Acid Oxidase from Cerastes cerastes Snake Venom. Toxins (Basel) 2021; 13:toxins13120904. [PMID: 34941741 PMCID: PMC8704781 DOI: 10.3390/toxins13120904] [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: 10/08/2021] [Revised: 11/01/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Snake venom proteins, which are responsible for deadly snakebite envenomation, induce severe injuries including neurotoxicity, myotoxicity, cardiotoxicity, hemorrhage, and the disruption of blood homeostasis. Yet, many snake-venom proteins have been developed as potential drugs for treating human diseases due to their pharmacological effects. In this study, we evaluated the use of, an L-amino acid oxidase isolated from Cerastes cerastes snake venom CC-LAAO, as a potential anti-glioblastoma drug, by investigating its in vivo and in vitro pharmacological effects. Our results showed that acute exposure to CC-LAAO at 1 and 2.5 µg/mL does not induce significant toxicity on vital organs, as indicated by the murine blood parameters including aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH) activities, and creatinine levels. The histopathological examination demonstrated that only at high concentrations did CC-LAAO induce inflammation and necrosis in several organs of the test subjects. Interestingly, when tested on human glioblastoma U87 cells, CC-LAAO induced a dose-dependent apoptotic effect through the H2O2 generated during the enzymatic reaction. Taken altogether, our data indicated that low concentration of CC-LAAO may be safe and may have potential in the development of anti-glioblastoma agents.
Collapse
Affiliation(s)
- Zaineb Abdelkafi-Koubaa
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (I.E.-D.); (J.J.); (N.S.-A.); (N.M.)
- Correspondence:
| | - Ines ELBini-Dhouib
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (I.E.-D.); (J.J.); (N.S.-A.); (N.M.)
| | - Soumaya Souid
- Laboratoire d’Epidémiologie Moléculaire et de Pathologie Expérimentale (LR16IPT04), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (S.S.); (K.E.-B.)
- School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe, LA 71201, USA
| | - Jed Jebali
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (I.E.-D.); (J.J.); (N.S.-A.); (N.M.)
| | - Raoudha Doghri
- Département d’Anatomie Pathologique, Institut Salah Azaiez, Bab Saadoun, Tunis 1006, Tunisia;
| | - Najet Srairi-Abid
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (I.E.-D.); (J.J.); (N.S.-A.); (N.M.)
| | - Khadija Essafi-Benkhadir
- Laboratoire d’Epidémiologie Moléculaire et de Pathologie Expérimentale (LR16IPT04), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (S.S.); (K.E.-B.)
| | - Olivier Micheau
- Lipides Nutrition Cancer, INSERM-UMR 1231, Université de Bourgogne Franche-Comté, UFR Science de Santé, 7 Bd Jeanne d’Arc, 21000 Dijon, France;
| | - Naziha Marrakchi
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia; (I.E.-D.); (J.J.); (N.S.-A.); (N.M.)
- Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
| |
Collapse
|
5
|
Valdés-Arellanes M, Ortega-Hernández G, Cervantes-Santos DM, Rendón-Barrón MJ, Madrigal-Santillán EO, Morales-González JA, Paniagua-Pérez R, Madrigal-Bujaidar E, Álvarez-González I. In vivo genotoxic and cytotoxic evaluation of venom obtained from the species of the snake ophryacus, cope, viperidae. TOXIN REV 2021. [DOI: 10.1080/15569543.2021.1975752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Mariel Valdés-Arellanes
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| | - Gerardo Ortega-Hernández
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| | - Doralí M. Cervantes-Santos
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| | - Michael Joshue Rendón-Barrón
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| | | | - José Antonio Morales-González
- Laboratorio de Medicina de Conservación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Ciudad de México, México
| | | | - Eduardo Madrigal-Bujaidar
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| | - Isela Álvarez-González
- Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México
| |
Collapse
|
6
|
Urra FA, Araya-Maturana R. Putting the brakes on tumorigenesis with snake venom toxins: New molecular insights for cancer drug discovery. Semin Cancer Biol 2020; 80:195-204. [PMID: 32428714 DOI: 10.1016/j.semcancer.2020.05.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 05/04/2020] [Accepted: 05/11/2020] [Indexed: 01/09/2023]
Abstract
Cancer cells exhibit molecular characteristics that confer them different proliferative capacities and survival advantages to adapt to stress conditions, such as deregulation of cellular bioenergetics, genomic instability, ability to promote angiogenesis, invasion, cell dormancy, immune evasion, and cell death resistance. In addition to these hallmarks of cancer, the current cytostatic drugs target the proliferation of malignant cells, being ineffective in metastatic disease. These aspects highlight the need to identify promising therapeutic targets for new generations of anti-cancer drugs. Toxins isolated from snake venoms are a natural source of useful molecular scaffolds to obtain agents with a selective effect on cancer cells. In this article, we discuss the recent advances in the molecular mechanisms of nine classes of snake toxins that suppress the hallmarks of cancer by induction of oxidative phosphorylation dysfunction, reactive oxygen species-dependent DNA damage, blockage of extracellular matrix-integrin signaling, disruption of cytoskeleton network and inhibition of growth factor-dependent signaling. The possible therapeutic implications of toxin-based anti-cancer drug development are also highlighted.
Collapse
Affiliation(s)
- Félix A Urra
- Programa de Farmacología Molecular y Clínica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 7800003, Chile; Network for Snake Venom Research and Drug Discovery, Santiago 7800003, Chile.
| | - Ramiro Araya-Maturana
- Network for Snake Venom Research and Drug Discovery, Santiago 7800003, Chile; Instituto de Química de Recursos Naturales, Universidad de Talca, Talca 3460000, Chile; Programa de Investigación Asociativa en Cáncer Gástrico, Universidad de Talca, Talca 3460000, Chile.
| |
Collapse
|
7
|
Menaldo DL, Costa TR, Ribeiro DL, Zambuzi FA, Antunes LM, Castro FA, Frantz FG, Sampaio SV. Immunomodulatory actions and epigenetic alterations induced by proteases from Bothrops snake venoms in human immune cells. Toxicol In Vitro 2019; 61:104586. [DOI: 10.1016/j.tiv.2019.06.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 06/28/2019] [Accepted: 06/29/2019] [Indexed: 12/25/2022]
|
8
|
A Synthetic Snake-Venom-Based Tripeptide Protects PC12 Cells from the Neurotoxicity of Acrolein by Improving Axonal Plasticity and Bioenergetics. Neurotox Res 2019; 37:227-237. [DOI: 10.1007/s12640-019-00111-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/11/2019] [Accepted: 09/12/2019] [Indexed: 02/07/2023]
|
9
|
Machado ART, Aissa AF, Ribeiro DL, Ferreira RS, Sampaio SV, Antunes LMG. BjussuLAAO-II induces cytotoxicity and alters DNA methylation of cell-cycle genes in monocultured/co-cultured HepG2 cells. J Venom Anim Toxins Incl Trop Dis 2019; 25:e147618. [PMID: 31131003 PMCID: PMC6527400 DOI: 10.1590/1678-9199-jvatitd-1476-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/22/2018] [Indexed: 12/18/2022] Open
Abstract
Background: The use of animal venoms and their toxins as material sources for
biotechnological applications has received much attention from the
pharmaceutical industry. L-amino acid oxidases from snake venoms (SV-LAAOs)
have demonstrated innumerous biological effects and pharmacological
potential against different cancer types. Hepatocellular carcinoma has
increased worldwide, and the aberrant DNA methylation of liver cells is a
common mechanism to promote hepatic tumorigenesis. Moreover, tumor
microenvironment plays a major role in neoplastic transformation. To
elucidate the molecular mechanisms responsible for the cytotoxic effects of
SV-LAAO in human cancer cells, this study aimed to evaluate the cytotoxicity
and the alterations in DNA methylation profiler in the promoter regions of
cell-cycle genes induced by BjussuLAAO-II, an LAAO from Bothrops
jaracussu venom, in human hepatocellular carcinoma (HepG2)
cells in monoculture and co-culture with endothelial (HUVEC) cells. Methods: BjussuLAAO-II concentrations were 0.25, 0.50, 1.00 and 5.00 μg/mL. Cell
viability was assessed by MTT assay and DNA methylation of the promoter
regions of 22 cell-cycle genes by EpiTect Methyl II PCR array. Results: BjussuLAAO-II decreased the cell viability of HepG2 cells in monoculture at
all concentrations tested. In co-culture, 1.00 and 5.00 μg/mL induced
cytotoxicity (p < 0.05). BjussuLAAO-II increased the
methylation of CCND1 and decreased the methylation of
CDKN1A in monoculture and GADD45A in
both cell-culture models (p < 0.05). Conclusion: Data showed BjussuLAAO-II induced cytotoxicity and altered DNA methylation of
the promoter regions of cell-cycle genes in HepG2 cells in monoculture and
co-culture models. We suggested the analysis of DNA methylation profile of
GADD45A as a potential biomarker of the cell cycle
effects of BjussuLAAO-II in cancer cells. The tumor microenvironment should
be considered to comprise part of biotechnological strategies during the
development of snake-toxin-based novel drugs.
Collapse
Affiliation(s)
- Ana Rita Thomazela Machado
- Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Alexandre Ferro Aissa
- Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Diego Luis Ribeiro
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Rui Seabra Ferreira
- Center for the Study of Venoms and Venomous Animals (CEVAP), São Paulo State University - UNESP, Botucatu, SP, Brazil
| | - Suely Vilela Sampaio
- Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto, SP, Brazil
| | - Lusânia Maria Greggi Antunes
- Department of Clinical Analysis, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto, SP, Brazil
| |
Collapse
|
10
|
Costa TR, Carone SEI, Tucci LFF, Menaldo DL, Rosa-Garzon NG, Cabral H, Sampaio SV. Kinetic investigations and stability studies of two Bothrops L-amino acid oxidases. J Venom Anim Toxins Incl Trop Dis 2018; 24:37. [PMID: 30534149 PMCID: PMC6280375 DOI: 10.1186/s40409-018-0172-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/07/2018] [Indexed: 01/29/2023] Open
Abstract
Background L-amino acid oxidases isolated from snake venoms (SV-LAAOs) are enzymes that have great therapeutic potential and are currently being investigated as tools for developing new strategies to treat various diseases, including cancer and bacterial infections. The main objective of this study was to make a brief evaluation of the enzymatic stability of two Bothrops LAAOs, one isolated from Bothrops jararacussu (BjussuLAAO-II) and the other from Bothrops moojeni (BmooLAAO-I) venoms. Methods and results The enzymatic activity and stability of both LAAOs were evaluated by microplate colorimetric assays, for which BjussuLAAO-II and BmooLAAO-I were incubated with different L-amino acid substrates, in the presence of different ions, and at different pH ranges and temperatures. BjussuLAAO-II and BmooLAAO-I demonstrated higher affinity for hydrophobic amino acids, such as Phe and Leu. The two enzymes showed high enzymatic activity in a wide temperature range, from 25 to 75 °C, and presented optimum pH around 7.0. Additionally, Zn2+, Al3+, Cu2+ and Ni2+ ions negatively modulated the enzymatic activity of both LAAOs. As to stability, BjussuLAAO-II and BmooLAAO-I showed high enzymatic activity for 42 days stored at 4 °C in neutral pH solution. Moreover, the glycan portions of both LAAOs were analyzed by capillary electrophoresis, which revealed that BjussuLAAO-II presented two main glycan portions with relative masses of 7.78 and 8.13 CGU, while BmooLAAO-I showed three portions of 7.58, 7.94 and 8.37 CGU. Conclusions Our results showed that, when stored properly, BjussuLAAO-II and BmooLAAO-I present enzymatic stability over a long time period, which is very important to allow the use of these enzymes in pharmacological studies of great impact in the medical field.
Collapse
Affiliation(s)
- Tássia R Costa
- 1Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, B. Monte Alegre, Ribeirão Preto, SP CEP 14040-903 Brazil
| | - Sante E I Carone
- 1Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, B. Monte Alegre, Ribeirão Preto, SP CEP 14040-903 Brazil
| | - Luiz F F Tucci
- 1Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, B. Monte Alegre, Ribeirão Preto, SP CEP 14040-903 Brazil
| | - Danilo L Menaldo
- 1Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, B. Monte Alegre, Ribeirão Preto, SP CEP 14040-903 Brazil
| | - Nathalia G Rosa-Garzon
- 2Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Ribeirão Preto, SP Brazil
| | - Hamilton Cabral
- 2Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Ribeirão Preto, SP Brazil
| | - Suely V Sampaio
- 1Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, B. Monte Alegre, Ribeirão Preto, SP CEP 14040-903 Brazil
| |
Collapse
|