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Faggi M, Vanzetti A, Teijeiro JM. Effect of glucose and reactive oxygen species on boar sperm induced-acrosome exocytosis. Res Vet Sci 2023; 164:105013. [PMID: 37742485 DOI: 10.1016/j.rvsc.2023.105013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/21/2023] [Accepted: 09/01/2023] [Indexed: 09/26/2023]
Abstract
Ejaculated boar spermatozoa can be liquid preserved for several days and be easily activated to produce physiological changes. One of the major changes is acrosome exocytosis that is physiologically related to capacitation. Glycolysis and reactive oxygen species (ROS) were studied regarding several boar sperm functions, but data available about their effect on boar sperm acrosome exocytosis are scarce. The objective of this work was to evaluate the effect of glucose and ROS on boar sperm acrosome exocytosis. We evaluated acrosome exocytosis by progesterone induction of capacitated sperm and assess viability, kinematics parameters, ROS levels, ATP content and Protein Kinase A activity in media with or without glucose and hydrogen peroxide or potassium chromate, as source of ROS. Our results show that glucose has no effect on acrosome exocytosis and also, it is not necessary for boar sperm capacitation, although it has a positive effect in the presence of ROS. On the other hand, ROS effects are related to spontaneous acrosome reaction. We conclude that glycolysis may function as a metabolic pathway that provides sustain but is not directly involved in boar sperm acrosome exocytosis and capacitation. Also, ROS do not promote capacitation in boar sperm, but affect spontaneous acrosome exocytosis.
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Affiliation(s)
- Melina Faggi
- Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Santa Fe, Argentina
| | - Agustín Vanzetti
- Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Santa Fe, Argentina
| | - Juan Manuel Teijeiro
- Laboratorio de Medicina Reproductiva, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario, Santa Fe, Argentina; CONICET.
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Henning H, Nguyen QT, Luther AM, Wallner U, Beyerbach M, Waberski D. In vitro storage of boar spermatozoa increases the demand of ATP for reactivation of motility. Andrology 2022; 10:1426-1440. [PMID: 35785447 DOI: 10.1111/andr.13226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 06/08/2022] [Accepted: 06/28/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Prolonging the shelf-life of liquid-preserved semen without compromising its fertilizing capacity may increase the efficiency of artificial insemination in pigs. Many fertilization-relevant processes are ATP dependent. The impact of semen storage and rewarming to body temperature on the energy status of sperm are as yet unknown. OBJECTIVES To investigate the energy status of boar spermatozoa during storage and subsequent rewarming, and to reveal the potential role of mitochondrial function for reactivation and maintenance of sperm motility. MATERIALS AND METHODS Extended semen samples (n = 7 boars) were used. Spermatozoa were challenged by storage at 17°C for seven days and incubation at 38°C for 180 minutes. The ATP concentration and energy charge (EC) in semen samples and lactate concentration in the extracellular medium were assessed. Viability and mitochondrial activity were determined by flow cytometry, and clustered single cell analysis of motility parameters were performed. RESULTS The energy status was not affected by semen storage (p>0.05). Rewarming resulted in a net reduction in ATP concentration which increased with storage time (maximum Day 5: -24.2±10.3 %), but was not accompanied by a loss in viability, motility or mitochondrial activity. Blocking glycolysis with 2-Deoxy-D-glucose prevented re-establishing of motility and mitochondrial activity after rewarming. Mitochondrial activity gradually subsided in virtually all spermatozoa during incubation at 38°C, while ATP and EC remained high. Concomitantly, extracellular lactate levels rose and sperm populations with lower velocity, increased linearity, and low lateral head-displacement grew larger. Size changes for major sperm subpopulations correlated with the percentage of viable sperm with high mitochondrial activity (r = 0.44 to 0.70 for individual subpopulations, p<0.01). CONCLUSION Storage of boar spermatozoa increases the demand of ATP for reactivation of sperm towards fast, non-linear and hyperactivation-like motility patterns upon rewarming. Maintenance of glycolysis seems to be decisive for sperm function after long-term storage in vitro. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Heiko Henning
- Unit for Reproductive Medicine / Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany.,Friedrich-Loeffler-Institut, Institute of Farm Animal Genetics, Höltystrasse 10, D-31535, Neustadt, Germany
| | - Quynh Thu Nguyen
- Unit for Reproductive Medicine / Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany.,Department of Animal Sciences, University of Göttingen, Albrecht-Thaer-Weg 3, D-37075, Göttingen, Germany
| | - Anne-Marie Luther
- Unit for Reproductive Medicine / Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany
| | - Ulrike Wallner
- Unit for Reproductive Medicine / Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany
| | - Martin Beyerbach
- Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany
| | - Dagmar Waberski
- Unit for Reproductive Medicine / Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Bünteweg 15, D-30559, Hannover, Germany
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Wang W, Liang K, Chang Y, Ran M, Zhang Y, Ali MA, Dai D, Qazi IH, Zhang M, Zhou G, Yang J, Angel C, Zeng C. miR-26a is Involved in Glycometabolism and Affects Boar Sperm Viability by Targeting PDHX. Cells 2020; 9:E146. [PMID: 31936222 PMCID: PMC7016825 DOI: 10.3390/cells9010146] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/26/2019] [Accepted: 12/27/2019] [Indexed: 02/06/2023] Open
Abstract
miR-26a is associated with sperm metabolism and can affect sperm motility and apoptosis. However, how miR-26a affects sperm motility remains largely unknown. Our previous study indicated that the PDHX gene is predicted to be a potential target of miR-26a, which is responsible for pyruvate oxidative decarboxylation which is considered as a key step for connecting glycolysis with oxidative phosphorylation. In this study, we first reported a potential relationship between miR-26a and PDHX and their expressions in fresh, frozen-thawed, and epididymal boar sperm. Then, sperm viability and survival were determined after transfection of miR-26a. mRNA and protein expression level of PDHX in the liquid-preserved boar sperm after transfection were also determined by RT-qPCR and Western Blot (WB). Our results showed that expression level of PDHX was significantly increased during sperm transit from epididymal caput to corpus and cauda. Similarly, expression of PDHX was significantly higher (P < 0.05) in fresh sperm as compared to epididymal cauda and frozen-thawed sperm. However, the expression of miR-26a in epididymal corpus sperm was significantly higher (P < 0.05) than that of caput and cauda sperm. Furthermore, after transfection of boar sperm with miR-26a mimic and inhibitor under liquid storage, the lowest and highest sperm viability was observed in miR-26a mimic and inhibitor treatment (P < 0.05), respectively. The protein levels of PDHX, after 24 and 48 h of transfection of miR-26a mimics and inhibitor, were notably decreased and increased (P < 0.05), respectively, as compared to negative control (NC) group. In conclusion, the novel and enticing findings of our study provide a reasonable evidence that miR-26a via PDHX, a link between glycolysis and oxidative phosphorylation, could regulate the glycometabolic pathway which eventually affect boar sperm viability and survival.
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Affiliation(s)
- Wencan Wang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Kai Liang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Yu Chang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Mingxia Ran
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Yan Zhang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Malik Ahsan Ali
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
- Department of Theriogenology, Riphah College of Veterinary Sciences, Lahore 54000, Pakistan
| | - Dinghui Dai
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Izhar Hyder Qazi
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
- Department of Veterinary Anatomy & Histology, Shaheed Benazir Bhutto University of Veterinary and Animal Sciences, Sakrand 67210, Pakistan
| | - Ming Zhang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Guangbin Zhou
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Jiandong Yang
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
| | - Christiana Angel
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China;
- Department of Veterinary Parasitology, Faculty of Veterinary Sciences, Shaheed Benazir Bhutto University of Veterinary and Animal Sciences, Sakrand 67210, Pakistan
| | - Changjun Zeng
- College of Animal Sciences and Technology, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; (W.W.); (K.L.); (Y.C.); (M.R.); (Y.Z.); (M.A.A.); (D.D.); (I.H.Q.); (M.Z.); (G.Z.); (J.Y.)
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Effect of diluent composition on the dynamics of sperm DNA fragmentation and other sperm quality parameters in ram during incubation at 37°C. Small Rumin Res 2015. [DOI: 10.1016/j.smallrumres.2015.05.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hereng TH, Elgstøen KBP, Eide L, Rosendal KR, Skålhegg BS. Serum albumin and HCO3- regulate separate pools of ATP in human spermatozoa. Hum Reprod 2014; 29:918-30. [PMID: 24578478 DOI: 10.1093/humrep/deu028] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
STUDY QUESTION Do the known capacitating agents HCO(3)(-) and serum albumin regulate the generation of ATP required for sperm motility and capacitation? SUMMARY ANSWER Serum albumin and HCO(3)(-) seem to regulate two separate pools of ATP by different mechanisms in human spermatozoa. WHAT IS KNOWN ALREADY Sperm capacitation is a maturation process that naturally occurs in the female reproductive tract preparing the sperm cell for fertilization. It is a highly energy-depending process as it involves hyperactive motility and substantial levels of protein phosphorylation. STUDY DESIGN, SIZE, DURATION Human sperm cells from four (motility experiments) and three (all other experiments) healthy donors were used. Untreated cells were compared with cells treated with HCO(3)(-) and serum albumin for up to 4 h. PARTICIPANTS/MATERIALS, SETTING, METHODS Changes in glycolysis and mitochondrial respiration rates upon treatment with serum albumin and HCO(3)(-) were analysed by metabolic tracing of (13)C-labelled substrates and respirometry studies, respectively. Levels of hyperactive spermatozoa and ATP content were measured during 4 h of incubation under capacitating conditions. MAIN RESULTS AND THE ROLE OF CHANCE We found that HCO(3)(-) significantly (P < 0.05) increased glycolytic flux by >3-folds via a cAMP/PKA sensitive pathway. This was accompanied by an increase in hyperactive motility. In contrast, serum albumin significantly increased endogenous ATP levels by 50% without stimulating hyperactive motility or glycolysis, indicating that this pool of ATP is separately located from the HCO(3)(-)-induced ATP. The increase in ATP induced by albumin could be mimicked by treatment with the cholesterol acceptors 2-hydroxypropyl- and methyl-β-cyclodextrin and counteracted by co-incubation with cholesterol sulphate to the level of the non-treated control (P < 0.05), pointing to cholesterol extraction from the sperm cell membrane as the main mechanism. However, the concentration of cyclodextrins needed to directly detect cholesterol extraction from the sperm cells was not compatible with maintenance of sperm viability. The increase in ATP seemed not to be dependent on the sperm-specific Ca(2+) channel CatSper. Finally, we demonstrated that neither HCO(3)(-) nor serum albumin stimulated mitochondrial respiration rates. However, serum albumin increased the respiratory capacity of mitochondria by >50%, an effect that was counteracted by HCO(3)(-). LIMITATIONS, REASONS FOR CAUTION Great variation in motility and capacitation is observed between sperm cells from different species. Hence, caution should be taken when extrapolating the findings in this work on human spermatozoa to sperm from other species. WIDER IMPLICATIONS OF THE FINDINGS It is already established that an efficient energy-generation is required to support sperm motility and capacitation. However, the mechanisms explaining how ATP production is regulated in spermatozoa are not fully understood. Our findings indicate that HCO(3)(-) stimulates hyperactive motility by increasing glycolytic flux and ATP production in a cAMP/PKA sensitive fashion. On the other hand, serum albumin seems to increase ATP concentration at a different location and by a mechanism different from glycolysis that involves extraction of cholesterol from the sperm cell membrane. These new insights into sperm metabolism may pave the way for both the development of new and improved male contraceptives and optimized assisted reproduction techniques. STUDY FUNDING The work was funded by Spermatech AS, The University of Oslo and the Research Council of Norway. COMPETING INTEREST(S) T.H.H. and K.R.R. are employees at Spermatech. B.S.S is a shareholder in Spermatech.
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Zwitterionic buffers preserve ram semen quality more efficiently than TRIS during storage at 15°C. Small Rumin Res 2011. [DOI: 10.1016/j.smallrumres.2010.08.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Campbell BK, Onions V, Kendall NR, Guo L, Scaramuzzi RJ. The effect of monosaccharide sugars and pyruvate on the differentiation and metabolism of sheep granulosa cells in vitro. Reproduction 2010; 140:541-50. [DOI: 10.1530/rep-10-0146] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The objective of this study was to investigate the effect of three monosaccharides or pyruvate on the ability of gonadotrophins to induce cellular proliferation and differentiation of cultured sheep granulosa cells. Lactate production and levels of mRNA expression for the glucose transporters SLC2A1, SLC2A4, SLC2A5 and SLC2A8 were also determined. No energy source in the culture media reduced cell number (50%) and oestradiol (E2) production. Dose and type of monosaccharide had a highly significant (P<0.001) effect on FSH-induced differentiation of the granulosa cells, and there was a highly significant interaction (P<0.001). Glucose supported higher levels of E2production than fructose, which was in turn higher than galactose (P<0.001). In contrast, pyruvate at low doses supported similar levels of E2production as glucose, but higher doses were markedly inhibitory to E2production (P<0.001). Cells responded positively to insulin (P<0.001) in the presence of all three monosaccharides. Glucose and the high doses of fructose resulted in the accumulation of lactate (P<0.001), but pyruvate, galactose and the low dose of fructose resulted in low lactate production. SLC2A5 expression was not detected and SLC2A8 expression was not affected, but SLC2A1 and SLC2A4 expression was depressed (P<0.05) by culture in the presence of fructose and glucose. These data show that glucose, metabolised under anoxic conditions to lactate, is the preferred energy substrate to support the gonadotrophin-induced differentiation of ovine granulosa cellsin vitro, and that fructose and pyruvate, but not galactose, are alternative energy substrates despite marked differences in the way these substrates are metabolised.
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Kamp G, Schmidt H, Stypa H, Feiden S, Mahling C, Wegener G. Regulatory properties of 6-phosphofructokinase and control of glycolysis in boar spermatozoa. Reproduction 2007; 133:29-40. [PMID: 17244730 DOI: 10.1530/rep-06-0082] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glycolysis is crucial for sperm functions (motility and fertilization), but how this pathway is regulated in spermatozoa is not clear. This prompted to study the location and the regulatory properties of 6-phosphofructokinase (PFK, EC 2.7.1.11), the most important element for control of glycolytic flux. Unlike some other glycolytic enzymes, PFK showed no tight binding to sperm structures. It could readily be extracted from ejaculated boar spermatozoa by sonication and was then chromatographically purified. At physiological pH, the enzyme was allosterically inhibited by near-physiological concentrations of its co-substrate ATP, which induced co-operativity, i.e. reduced the affinity for the substrate fructose 6-phosphate. Inhibition by ATP was reinforced by citrate and H+. Above pH 8, PFK lost all its regulatory properties and showed maximum activity. However, in the physiological pH range, PFK activity was very sensitive to small changes in effectors. At near-physiological substrate concentrations, PFK activity requires activators (de-inhibitors) of which the combination of AMP and fructose 2,6-bisphosphate (F2,6P2) was most efficient as a result of synergistic effects. The kinetics of PFK suggest AMP, F2,6P2, H+, and citrate as allosteric effectors controlling PFK activity in boar spermatozoa. Using immunogold labeling, PFK was localized in the mid-piece and principal piece of the flagellum as well as in the acrosomal area at the top of the head and in the cytoplasmic droplets released from the mid-piece after ejaculation.
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Affiliation(s)
- G Kamp
- Institut für Zoologie, Johannes Gutenberg-Universität, Becherweg 9-11, D-55099 Mainz, Germany
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Schistosoma mansoni: biochemical characterization of lactate transporters or similar proteins. Exp Parasitol 2006; 114:180-8. [PMID: 16682030 DOI: 10.1016/j.exppara.2006.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 03/08/2006] [Accepted: 03/09/2006] [Indexed: 11/30/2022]
Abstract
While in medium containing glucose, schistosomes exhibit homolactic fermentation. Accumulation of lactate acid in tissue fluid causes lowering of pH and a resultant inhibition of metabolic pathways. This requires lactate transporter protein in homolactic fermentors to facilitate the translocation of lactate(-) and [H(+)] across their plasma membrane. The ex-vivo experiment assessed lactic acid secretion by adult worms in absence and the presence of lactic acid transporter protein inhibitors. Phloretin and alpha-cyano-4-hydroxycinnamate caused a combined 25-35% inhibition of lactic acid secretion and probenecid increased this inhibition to 65% of control values. The removal of inhibitors resulted in 80% recovery of lactic acid secretion. In the in-vitro studies using vesicles isolated from adult worms and from schistosomula, the effects of phloretin and alpha-cyano-4-hydroxycinnamate were greater, each causing approximately 80% inhibition independently. The data obtained in this study demonstrate the presence of lactic acid transporters or similar proteins in Schistosoma mansoni.
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