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Kitzberger F, Yang SM, Týč J, Bílý T, Nebesářová J. An advanced fast method for the evaluation of multiple immunolabelling using gold nanoparticles based on low-energy STEM. Sci Rep 2024; 14:10150. [PMID: 38698090 PMCID: PMC11065996 DOI: 10.1038/s41598-024-60314-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 04/21/2024] [Indexed: 05/05/2024] Open
Abstract
We present a powerful method for the simultaneous detection of Au nanoparticles located on both sides of ultrathin sections. The method employs a high-resolution scanning electron microscope (HRSEM) operating in scanning transmission electron microscopy (STEM) mode in combination with the detection of backscattered electrons (BSE). The images are recorded simultaneously during STEM and BSE imaging at the precisely selected accelerating voltage. Under proper imaging conditions, the positions of Au nanoparticles on the top or bottom sides can be clearly differentiated, hence showing this method to be suitable for multiple immunolabelling using Au nanoparticles (NPs) as markers. The difference between the upper and lower Au NPs is so large that it is possible to apply common software tools (such as ImageJ) to enable their automatic differentiation. The effects of the section thickness, detector settings and accelerating voltage on the resulting image are shown. Our experimental results correspond to the results modelled in silico by Monte Carlo (MC) simulations.
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Affiliation(s)
- František Kitzberger
- Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre CAS, 370 05, České Budějovice, Czech Republic.
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic.
| | - Shun-Min Yang
- Laboratory of Evolutionary Protistology, Institute of Parasitology, Biology Centre CAS, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Jiří Týč
- Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre CAS, 370 05, České Budějovice, Czech Republic
| | - Tomáš Bílý
- Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre CAS, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Jana Nebesářová
- Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre CAS, 370 05, České Budějovice, Czech Republic.
- Faculty of Science, Charles University, 128 00, Prague 2, Czech Republic.
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Bzducha-Wróbel A, Farkaš P, Bieliková S, Čížová A, Sujkowska-Rybkowska M. How do the carbon and nitrogen sources affect the synthesis of β-(1,3/1,6)-glucan, its structure and the susceptibility of Candida utilis yeast cells to immunolabelling with β-(1,3)-glucan monoclonal antibodies? Microb Cell Fact 2024; 23:28. [PMID: 38243245 PMCID: PMC10799355 DOI: 10.1186/s12934-024-02305-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/14/2024] [Indexed: 01/21/2024] Open
Abstract
BACKGROUND The need to limit antibiotic therapy due to the spreading resistance of pathogenic microorganisms to these medicinal substances stimulates research on new therapeutic agents, including the treatment and prevention of animal diseases. This is one of the goals of the European Green Deal and the Farm-To-Fork strategy. Yeast biomass with an appropriate composition and exposure of cell wall polysaccharides could constitute a functional feed additive in precision animal nutrition, naturally stimulating the immune system to fight infections. RESULTS The results of the research carried out in this study showed that the composition of Candida utilis ATCC 9950 yeast biomass differed depending on growth medium, considering especially the content of β-(1,3/1,6)-glucan, α-glucan, and trehalose. The highest β-(1,3/1,6)-glucan content was observed after cultivation in deproteinated potato juice water (DPJW) as a nitrogen source and glycerol as a carbon source. Isolation of the polysaccharide from yeast biomass confirmed the highest yield of β-(1,3/1,6)-glucan after cultivation in indicated medium. The differences in the susceptibility of β-(1,3)-glucan localized in cells to interaction with specific β-(1,3)-glucan antibody was noted depending on the culture conditions. The polymer in cells from the DPJW supplemented with glycerol and galactose were labelled with monoclonal antibodies with highest intensity, interestingly being less susceptible to such an interaction after cell multiplication in medium with glycerol as carbon source and yeast extract plus peptone as a nitrogen source. CONCLUSIONS Obtained results confirmed differences in the structure of the β-(1,3/1,6)-glucan polymers considering side-chain length and branching frequency, as well as in quantity of β-(1,3)- and β-(1,6)-chains, however, no visible relationship was observed between the structural characteristics of the isolated polymers and its susceptibility to immunolabeling in whole cells. Presumably, other outer surface components and molecules can mask, shield, protect, or hide epitopes from antibodies. β-(1,3)-Glucan was more intensely recognized by monoclonal antibody in cells with lower trehalose and glycogen content. This suggests the need to cultivate yeast biomass under appropriate conditions to fulfil possible therapeutic functions. However, our in vitro findings should be confirmed in further studies using tissue or animal models.
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Affiliation(s)
- Anna Bzducha-Wróbel
- Department of Food Biotechnology and Microbiology, Institute of Food Sciences, Warsaw University of Life Sciences, Nowoursynowska 159C Street, 02-787, Warsaw, Poland.
| | - Pavol Farkaš
- Department of Glycobiotechnology, Institute of Chemistry Slovak Academy of Sciences, Dúbravská Cesta 9, 84538, Bratislava, Slovakia.
| | - Sandra Bieliková
- Department of Glycomaterials, Institute of Chemistry Slovak Academy of Sciences, Dúbravská Cesta 9, 84538, Bratislava, Slovakia
| | - Alžbeta Čížová
- Department of Glycomaterials, Institute of Chemistry Slovak Academy of Sciences, Dúbravská Cesta 9, 84538, Bratislava, Slovakia
| | - Marzena Sujkowska-Rybkowska
- Department of Botany, Warsaw, Institute of Biology, University of Life Sciences, Nowoursynowska 159C Street, 02-787, Warsaw, Poland
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Makai D, Mihók E, Polgári D, Cseh A, Lenykó-Thegze A, Sepsi A, Sági L. Rapid in-solution preparation of somatic and meiotic plant cell nuclei for high-quality 3D immunoFISH and immunoFISH-GISH. Plant Methods 2023; 19:80. [PMID: 37553677 PMCID: PMC10408160 DOI: 10.1186/s13007-023-01061-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 07/22/2023] [Indexed: 08/10/2023]
Abstract
BACKGROUND Though multicolour labelling methods allow the routine detection of a wide range of fluorescent (immuno)probe types in molecular cytogenetics, combined applications for the simultaneous in situ detection of proteins and nucleic acids are still sporadic in plant cell biology. A major bottleneck has been the availability of high-quality plant nuclei with a balance between preservation of 3D ultrastructure and maintaining immunoreactivity. The aim of this study was to develop a quick and reliable procedure to prepare plant nuclei suitable for various combinations of immunolabelling and fluorescence in situ hybridisation methods (immunoFISH-GISH). RESULTS The mechanical removal of the cell wall and cytoplasm, instead of enzymatic degradation, resulted in a gentle, yet effective, cell permeabilisation. Rather than manually releasing the nuclei from the fixed tissues, the procedure involves in-solution cell handling throughout the fixation and the preparation steps as ended with pipetting the pure nuclei suspension onto microscope slides. The optimisation of several critical steps is described in detail. Finally, the procedure is shown to be compatible with immunolabelling, FISH and GISH as well as their simultaneous combinations. CONCLUSION A simple plant cell nuclei preparation procedure was developed for combined immunolabelling-in situ hybridisation methods. The main and critical elements of the procedure are: a short period of fixation, incorporation of detergents to facilitate the fixation of tissues and the penetration of probes, tissue grinding to eliminate unwanted cell components, and an optimal buffer to handle nuclei. The procedure is time efficient and is easily transferable without prior expertise.
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Affiliation(s)
- Diána Makai
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary
- Doctoral School of Plant Sciences, Hungarian University of Agriculture and Life Sciences, Gödöllő, 2100, Hungary
| | - Edit Mihók
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary
- Doctoral School of Plant Sciences, Hungarian University of Agriculture and Life Sciences, Gödöllő, 2100, Hungary
| | - Dávid Polgári
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary
- Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, 2100, Hungary
| | - András Cseh
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary
| | - Andrea Lenykó-Thegze
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary
- Doctoral School of Biology, Eötvös Loránd University, Budapest, 1117, Hungary
| | - Adél Sepsi
- Centre for Agricultural Research, Eötvös Loránd Research Network, Martonvásár, 2462, Hungary.
| | - László Sági
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Plant Biotechnology Section, Centre for Agricultural Research, Martonvásár, 2462, Hungary.
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Kyslík J, Vancová M, Bartošová-Sojková P, Lövy A, Holzer AS, Fiala I. Expression profiling and cellular localization of myxozoan minicollagens during nematocyst formation and sporogenesis. Int J Parasitol 2022:S0020-7519(22)00104-7. [PMID: 35970383 DOI: 10.1016/j.ijpara.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/14/2022] [Accepted: 07/19/2022] [Indexed: 11/20/2022]
Abstract
In free-living cnidarians, minicollagens are major structural components in the biogenesis of nematocysts. Recent sequence mining and proteomic analysis demonstrate that minicollagens are also expressed by myxozoans, a group of evolutionarily ancient cnidarian endoparasites. Nonetheless, the presence and abundance of nematocyst-associated genes/proteins in nematocyst morphogenesis have never been studied in Myxozoa. Here, we report the gene expression profiles of three myxozoan minicollagens, ncol-1, ncol-3, and the recently identified noncanonical ncol-5, during the intrapiscine development of Myxidium lieberkuehni, the myxozoan parasite of the northern pike, Esox lucius. Moreover, we localized the myxozoan-specific minicollagen Ncol-5 in the developing myxosporean stages by Western blotting, immunofluorescence, and immunogold electron microscopy. We found that expression of minicollagens was spatiotemporally restricted to developing nematocysts within the myxospores during sporogenesis. Intriguingly, Ncol-5 is localized in the walls of nematocysts and predominantly in nematocyst tubules. Overall, we demonstrate that despite being significantly reduced in morphology, myxozoans retain structural components associated with nematocyst development in free-living cnidarians. Furthermore, our findings have practical implications for future functional and comparative studies as minicollagens are useful markers of the developmental phase of myxozoan parasites.
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Osborn A, Caruana D, Furness DN, Evans MG. Electrical and Immunohistochemical Properties of Cochlear Fibrocytes in 3D Cell Culture and in the Excised Spiral Ligament of Mice. J Assoc Res Otolaryngol 2022; 23:183-193. [PMID: 35041102 PMCID: PMC8964888 DOI: 10.1007/s10162-021-00833-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 12/23/2021] [Indexed: 11/17/2022] Open
Abstract
Fibrocyte degeneration in the cochlear lateral wall is one possible pathology of age-related metabolic hearing loss (presbycusis). Within the lateral wall fibrocytes play a role in potassium recycling and maintenance of the endocochlear potential. It has been proposed that cell replacement therapy could prevent fibrocyte degeneration in the CD/1 mouse model of hearing loss. For this to work, the replacement fibrocytes would need to take over the structural and physiological role of those lost. We have grown lateral wall fibrocytes from neonatal CD/1 mice in a 3D-collagen gel culture with the aim of assessing their functional similarity to native lateral wall fibrocytes, the latter in a slice preparation and in excised spiral ligament pieces. We have compared cultured and native fibrocytes using both immuno-labelling of characteristic proteins and single cell electrophysiology. Cultured fibrocytes exhibited rounded cell bodies with extending processes. They labelled with marker antibodies targeting aquaporin 1 and calcium-binding protein S-100, precluding an unambiguous identification of fibrocyte type. In whole-cell voltage clamp, both native and cultured fibrocytes exhibited non-specific currents and voltage-dependent K+ currents. The non-specific currents from gel-cultured and excised spiral ligament fibrocytes were partially and reversibly blocked by external TEA (10 mM). The TEA-sensitive current had a mean reversal potential of + 26 mV, suggesting a permeability sequence of Na+ > K+. These findings indicate that 3D-cultured fibrocytes share a number of characteristics with native spiral ligament fibrocytes and thus might represent a suitable population for transplantation therapy aimed at treating age-related hearing loss.
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Affiliation(s)
- A Osborn
- School of Life Sciences, Keele University, Stoke-on-Trent, ST5 5BG, UK
| | - D Caruana
- School of Life Sciences, Keele University, Stoke-on-Trent, ST5 5BG, UK.,Life & Health Sciences, Aston University, Birmingham, B4 7ET, UK
| | - D N Furness
- School of Life Sciences, Keele University, Stoke-on-Trent, ST5 5BG, UK
| | - M G Evans
- School of Life Sciences, Keele University, Stoke-on-Trent, ST5 5BG, UK.
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Ori F, Leonardi M, Faccio A, Sillo F, Iotti M, Pacioni G, Balestrini R. Synthesis and ultrastructural observation of arbutoid mycorrhizae of black truffles (Tuber melanosporum and T. aestivum). Mycorrhiza 2020; 30:715-723. [PMID: 33079241 PMCID: PMC7591440 DOI: 10.1007/s00572-020-00985-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/18/2020] [Indexed: 06/11/2023]
Abstract
Arbutus unedo (the strawberry tree) is a Mediterranean shrub which forms arbutoid mycorrhizae with a variety of Asco- and Basidiomycetes. After the discovery of the mycorrhizal symbiosis between A. unedo and Tuber borchii, in this study, arbutoid mycorrhizae were synthetized in greenhouse with Tuber aestivum and Tuber melanosporum. Six months after inoculation, both species colonized the roots of all inoculated A. unedo seedlings, but mature mycorrhizae were only observed after 12 months. Ultrastructure analysis of Tuber arbutoid mycorrhizae was described for the first time, showing, as observed in typical endosymbiosis, a rearrangement of host cells and the creation of an interface compartment with both truffle species. Immunolabelling experiments suggested that pectins are not present in the interface matrix surrounding the intracellular hyphae. Thus, the ability to establish symbiosis with A. unedo seems to be a common feature in the genus Tuber, opening up the possibility to use this plant for mycorrhization with valuable truffles. This could represent an important economic opportunity in Mediterranean areas by combining the production of truffles, edible fruits and valued honey.
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Affiliation(s)
- Francesca Ori
- Department of Life, Health and Environmental Sciences, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy
| | - Marco Leonardi
- Department of Life, Health and Environmental Sciences, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy
| | - Antonella Faccio
- National Research Council, Institute for Sustainable Plant Protection, Viale Mattioli 25, 10125, Torino, Italy
| | - Fabiano Sillo
- National Research Council, Institute for Sustainable Plant Protection, Viale Mattioli 25, 10125, Torino, Italy
| | - Mirco Iotti
- Department of Life, Health and Environmental Sciences, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy.
| | - Giovanni Pacioni
- Department of Life, Health and Environmental Sciences, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy
| | - Raffaella Balestrini
- National Research Council, Institute for Sustainable Plant Protection, Viale Mattioli 25, 10125, Torino, Italy
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Nduohosewo IS, Ekong MB. Murine's amygdala microstructure and elevated plus maze activities following R. vomitoria root bark and G. latifolium leaf extracts administration. Anat Sci Int 2020; 95:342-55. [PMID: 32006225 DOI: 10.1007/s12565-020-00527-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 01/22/2020] [Indexed: 12/31/2022]
Abstract
R. vomitoria (RV), a plant used locally in the management of psychotic disorders, adversely affects the brain functionally and structurally. Such adverse reports, as well as the potential of G. latifolium (GL) to mitigate same warranted this investigation on the combined actions of RV and GL on the amygdala. Twenty-four male CD-1 mice weighing 22-27 g were divided into four groups (n = 6): Control (20 ml/kg body weight, b.w., distilled water); RV (200 mg/kg b.w.), GL (200 mg/kg b.w.), and RV (200 mg/kg b.w.) and GL (200 mg/kg b.w.) combination orally, and for 14 days. On day 15, the elevated-plus maze test was carried out and the animals sacrificed, and processed for histological and immunohistochemical studies. Neurobehavioural results showed significant decrease (p[Formula: see text] 0.001) in stretch-attend posture, time spent in closed arms, grooming frequency, protected head-dip, as well as significantly (p [Formula: see text] 0.01) increased time spent in the open arms and unprotected head-dips of the RV group. The combined RV and GL groups showed no such differences in these parameters. Histologically, the amygdala showed hypertrophied cells, with pyknotic and karyorrhectic nuclei, and reduced expression of Nissl substance in the RV group, while the combined RV and GL group showed less degenerative features. Glial fibrillary acidic protein expression (GFAP) was increased in the RV group, while the combined RV and GL group showed reduced expression. In conclusion, RV root bark extract has adverse effects on the microstructure of murines' amygdala and their behaviour, which may be ameliorated by GL.
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Bloomer SA, Moyer ED, Brown KE, Kregel KC. Aging results in accumulation of M1 and M2 hepatic macrophages and a differential response to gadolinium chloride. Histochem Cell Biol 2019; 153:37-48. [PMID: 31691025 DOI: 10.1007/s00418-019-01827-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2019] [Indexed: 02/06/2023]
Abstract
Macrophages have vital roles in innate immunity by modulating the inflammatory response via their ability to alter their phenotype from pro-inflammatory (M1) to anti-inflammatory (M2). Aging increases activation of the innate immune system, and macrophage numbers increase in the aged liver. Since macrophages also produce free radical molecules, they are a potential source of age-related oxidative injury in the liver. This study evaluated macrophage phenotype in the aged liver and whether the increase in the number of macrophages with aging is associated with enhanced hepatic oxidative stress. Hepatic macrophage phenotype and oxidative stress were evaluated 2 days after a single intraperitoneal injection of saline or gadolinium chloride (GdCl3, 10 mg/kg) in young (6 months) and aged (24 months) Fischer 344 rats. GdCl3 has been shown to decrease the expression of macrophage-specific markers and impair macrophage phagocytosis in the liver. Saline-treated aged rats demonstrated greater numbers of both M1 (HO-1+/iNOS+) and M2 (HO-1+/CD163+) macrophages, without evidence of a phenotypic shift. GdCl3 did not alter levels of dihydroethidium fluorescence or malondialdehyde, suggesting that macrophages are not a major contributor to steady-state levels of oxidative stress. However, GdCl3 decreased M1 and M2 macrophage markers in both age groups, an effect that was attenuated in aged rats. In old animals, GdCl3 decreased iNOS expression to a greater extent than HO-1 or CD163. These results suggest a novel effect of aging on macrophage biology and that GdCl3 shifts hepatic macrophage polarization to the M2 phenotype in aged animals.
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Affiliation(s)
- Steven A Bloomer
- Division of Science and Engineering, Penn State University, Abington College, 1600 Woodland Rd., Abington, PA, 19001, USA.
| | - Eric D Moyer
- Division of Science and Engineering, Penn State University, Abington College, 1600 Woodland Rd., Abington, PA, 19001, USA
| | - Kyle E Brown
- Iowa City Veterans Administration Medical Center, Iowa City, IA, 52242, USA.,Division of Gastroenterology-Hepatology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, 52242, USA.,Program in Free Radical and Radiation Biology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, 52242, USA
| | - Kevin C Kregel
- Department of Health and Human Physiology, The University of Iowa, Iowa City, IA, 52242, USA
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Alibardi L. Immunodetection of ephrin receptors in the regenerating tail of the lizard Podarcis muralis suggests stimulation of differentiation and muscle segmentation. Zool Res 2019; 40:416-426. [PMID: 31111695 PMCID: PMC6755122 DOI: 10.24272/j.issn.2095-8137.2019.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Ephrin receptors are the most common tyrosine kinase effectors operating during development. Ephrin receptor genes are reported to be up-regulated in the regenerating tail of the Podarcis muralis lizard. Thus, in the current study, we investigated immunolocalization of ephrin receptors in the Podarcis muralis tail during regeneration. Weak immunolabelled bands for ephrin receptors were detected at 15-17 kDa, with a stronger band also detected at 60-65 kDa. Labelled cells and nuclei were seen in the basal layer of the apical wound epidermis and ependyma, two key tissues stimulating tail regeneration. Strong nuclear and cytoplasmic labelling were present in the segmental muscles of the regenerating tail, sparse blood vessels, and perichondrium of regenerating cartilage. The immunolocalization of ephrin receptors in muscle that gives rise to large portions of new tail tissue was correlated with their segmentation. This study suggests that the high localization of ephrin receptors in differentiating epidermis, ependyma, muscle, and cartilaginous cells is connected to the regulation of cell proliferation through the activation of programs for cell differentiation in the proximal regions of the regenerating tail. The lower immunolabelling of ephrin receptors in the apical blastema, where signaling proteins stimulating cell proliferation are instead present, helps maintain the continuous growth of this region.
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Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and Department of Biology, University of Bologna, Bologna 40126, Italy; E-mail:
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Ekong MB, Ekpo MM, Akpanyung EO, Nwaokonko DU. Neuroprotective effect of Moringa oleifera leaf extract on aluminium-induced temporal cortical degeneration. Metab Brain Dis 2017; 32:1437-1447. [PMID: 28397152 DOI: 10.1007/s11011-017-0011-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 04/03/2017] [Indexed: 10/19/2022]
Abstract
Aluminium (Al), one of the metals implicated in neurodegeneration easily gain access to the nervous system through its presence in many manufactured foods, medicines and drinking water, and causes neurotoxicity utilizing the reactive oxygen specie pathway. The need to curtail these effects on the nervous system motivated the use of the plant Moringa oleifera (MO). This study thus, investigated the neuroprotective effects of MO leaf extract on aluminium-induced temporal cortical degeneration in rats. 24 male albino Wistar rats were grouped (n = 6) into control (1 ml/kg distilled water), l00 mg/kg aluminium chloride (AlCl3), 300 mg/kg MO, and 100 mg/kg AlCl3 and 300 mg/kg MO groups. The administration lasted for 28 days and the rats were sacrificed on day 29 by perfusion-fixation after blood was obtained for serum Al estimation. The brain tissues were then routinely processed for some histological and immunnolabelling studies. There was no significant difference in serum Al in the test groups. Histological results showed atrophied and karyorrhetic cells with loss of Nissl substance in the temporal cortex of the AlCl3 group, while no adverse effect was observed in the cytoarchitecture of the temporal cortex and Nissl substance of the MO group. However, groups which were administered AlCl3 simultaneously with MO extract showed less degenerative features in the cyto-architecture of the temporal cortex with normal Nissl substance staining. There was increased neuron specific enolase (NSE) and glial fibrillary acidic protein (GFAP) expressions in the AlCl3 group, while the MO group also showed increased NSE but decreased GFAP expression. However, the group which were administered AlCl3 simultaneously with MO extract showed less expression of NSE and GFAP. In conclusion, MO protects against Al-induced neurotoxicity of the temporal cortex of rats.
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Affiliation(s)
- Moses B Ekong
- Department of Anatomy, Faculty of Basic Medical Sciences, University of Uyo, Uyo, Nigeria.
| | - Mfon M Ekpo
- Department of Anatomy, Faculty of Basic Medical Sciences, University of Uyo, Uyo, Nigeria
| | - Edet O Akpanyung
- Department of Biochemistry, Faculty of Basic Medical Sciences, University of Uyo, Uyo, Nigeria
| | - Dennis U Nwaokonko
- Department of Biochemistry, Faculty of Basic Medical Sciences, University of Uyo, Uyo, Nigeria
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Stanly TA, Fritzsche M, Banerji S, García E, Bernardino de la Serna J, Jackson DG, Eggeling C. Critical importance of appropriate fixation conditions for faithful imaging of receptor microclusters. Biol Open 2016; 5:1343-50. [PMID: 27464671 PMCID: PMC5051640 DOI: 10.1242/bio.019943] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Receptor clustering is known to trigger signalling events that contribute to critical changes in cellular functions. Faithful imaging of such clusters by means of fluorescence microscopy relies on the application of adequate cell fixation methods prior to immunolabelling in order to avoid artefactual redistribution by the antibodies themselves. Previous work has highlighted the inadequacy of fixation with paraformaldehyde (PFA) alone for efficient immobilisation of membrane-associated molecules, and the advantages of fixation with PFA in combination with glutaraldehyde (GA). Using fluorescence microscopy, we here highlight how inadequate fixation can lead to the formation of artefactual clustering of receptors in lymphatic endothelial cells, focussing on the transmembrane hyaluronan receptors LYVE-1 and CD44, and the homotypic adhesion molecule CD31, each of which displays their native diffuse surface distribution pattern only when visualised with the right fixation techniques, i.e. PFA/GA in combination. Fluorescence recovery after photobleaching (FRAP) confirms that the artefactual receptor clusters are indeed introduced by residual mobility. In contrast, we observed full immobilisation of membrane proteins in cells that were fixed and then subsequently permeabilised, irrespective of whether the fixative was PFA or PFA/GA in combination. Our study underlines the importance of choosing appropriate sample preparation protocols for preserving authentic receptor organisation in advanced fluorescence microscopy. Summary: Commonly used fixation protocols during immunolabelling can result in artefactual protein distribution. We highlight the artefacts in images and provide fixation conditions for studying membrane receptor organisation.
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Affiliation(s)
- Tess A Stanly
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Marco Fritzsche
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Suneale Banerji
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Esther García
- Wolfson Imaging Centre, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Jorge Bernardino de la Serna
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK Science & Technology Facilities Council, Rutherford Appleton Laboratory, Central Laser Facility, Research Complex at Harwell, Harwell-Oxford Campus, Oxford OX11 0FA, UK
| | - David G Jackson
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK Wolfson Imaging Centre, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
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Sharma S, Martin S, Sykes MJ, Dave A, Hewitt AW, Burdon KP, Ronci M, Voelcker NH, Craig JE. Biological effect of LOXL1 coding variants associated with pseudoexfoliation syndrome. Exp Eye Res 2016; 146:212-23. [PMID: 26997634 DOI: 10.1016/j.exer.2016.03.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 03/01/2016] [Accepted: 03/13/2016] [Indexed: 01/08/2023]
Abstract
Pseudoexfoliation (PEX) syndrome is a systemic disease involving the extracellular matrix. It increases the risk of glaucoma, an irreversible cause of blindness, and susceptibility to heart disease, stroke and hearing loss. Single nucleotide polymorphisms (SNPs) in the LOXL1 (Lysyl oxidase-like 1) gene are the major known genetic risk factor for PEX syndrome. Two coding SNPs, rs1048861 (G > T; Arg141Leu) and rs3825942 (G > A; Gly153Asp), in the LOXL1 gene are strongly associated with the disease risk in multiple populations worldwide. In the present study, we investigated functional effects of these SNPs on the LOXL1 protein. We show through molecular modelling that positions 141 and 153 are likely surface residues and hence possible recognition sites for protein-protein interactions; the Arg141Leu and Gly153Asp substitutions cause charge changes that would lead to local differences in protein electrostatic potential and in turn the potential to modify protein-protein interactions. In RFL-6 rat fetal lung fibroblast cells ectopically expressing the LOXL1 protein variants related to PEX (Arg141_Gly153, Arg141_Asp153 or Leu141_Gly153), immunoprecipitation of the secreted variants showed differences in their processing by endogenous proteins, possibly Bone morphogenetic protein-1 (BMP-1) that cleaves and leads to enzymatic activation of LOXL1. Immunofluorescence labelling of the ectopically expressed protein variants in RFL-6 cells showed no significant difference in their extracellular accumulation tendency. In conclusion, this is the first report of a biological effect of the coding SNPs in the LOXL1 gene associated with PEX syndrome, on the LOXL1 protein. The findings indicate that the disease associated coding variants themselves may be involved in the manifestation of PEX syndrome.
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Amrehn E, Aschenbrenner AK, Heller A, Spring O. Localization of sesquiterpene lactone biosynthesis in cells of capitate glandular trichomes of Helianthus annuus (Asteraceae). Protoplasma 2016; 253:447-455. [PMID: 25956500 DOI: 10.1007/s00709-015-0823-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 04/20/2015] [Indexed: 06/04/2023]
Abstract
Capitate glandular trichomes (CGT) of sunflower, Helianthus annuus, synthesize bioactive sesquiterpene lactones (STLs) within a short period of only a few days during trichome development. In the current project, the subcellular localization of H. annuus germacrene A monooxygenase (HaGAO), a key enzyme of the STL biosynthesis in sunflower CGT, was investigated. A polyclonal antibody raised against this enzyme was used for immunolabelling. HaGAO was found in secretory and stalk cells of CGT. This correlated with the appearance of smooth endoplasmic reticulum in both cell types. Stalk cells and secretory cells differed in form, size and types of plastids, but both had structures necessary for secretion. No HaGAO-specific immunoreaction was found in sunflower leaf tissue outside of CGT or in developing CGT before the secretory phase had started. Our results indicated that not only secretory cells but also nearly all cells of the CGT were involved in the biosynthesis of STL and that this process was not linked to the presence or absence of a specific type of plastid.
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Affiliation(s)
- Evelyn Amrehn
- Institute of Botany, University Hohenheim, Garbenstraße 30, 70599, Stuttgart, Germany
| | | | - Annerose Heller
- Institute of Botany, University Hohenheim, Garbenstraße 30, 70599, Stuttgart, Germany
| | - Otmar Spring
- Institute of Botany, University Hohenheim, Garbenstraße 30, 70599, Stuttgart, Germany.
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Loussert Fonta C, Leis A, Mathisen C, Bouvier DS, Blanchard W, Volterra A, Lich B, Humbel BM. Analysis of acute brain slices by electron microscopy: a correlative light-electron microscopy workflow based on Tokuyasu cryo-sectioning. J Struct Biol 2014; 189:53-61. [PMID: 25448886 DOI: 10.1016/j.jsb.2014.10.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 10/16/2014] [Accepted: 10/20/2014] [Indexed: 10/24/2022]
Abstract
Acute brain slices are slices of brain tissue that are kept vital in vitro for further recordings and analyses. This tool is of major importance in neurobiology and allows the study of brain cells such as microglia, astrocytes, neurons and their inter/intracellular communications via ion channels or transporters. In combination with light/fluorescence microscopies, acute brain slices enable the ex vivo analysis of specific cells or groups of cells inside the slice, e.g. astrocytes. To bridge ex vivo knowledge of a cell with its ultrastructure, we developed a correlative microscopy approach for acute brain slices. The workflow begins with sampling of the tissue and precise trimming of a region of interest, which contains GFP-tagged astrocytes that can be visualised by fluorescence microscopy of ultrathin sections. The astrocytes and their surroundings are then analysed by high resolution scanning transmission electron microscopy (STEM). An important aspect of this workflow is the modification of a commercial cryo-ultramicrotome to observe the fluorescent GFP signal during the trimming process. It ensured that sections contained at least one GFP astrocyte. After cryo-sectioning, a map of the GFP-expressing astrocytes is established and transferred to correlation software installed on a focused ion beam scanning electron microscope equipped with a STEM detector. Next, the areas displaying fluorescence are selected for high resolution STEM imaging. An overview area (e.g. a whole mesh of the grid) is imaged with an automated tiling and stitching process. In the final stitched image, the local organisation of the brain tissue can be surveyed or areas of interest can be magnified to observe fine details, e.g. vesicles or gold labels on specific proteins. The robustness of this workflow is contingent on the quality of sample preparation, based on Tokuyasu's protocol. This method results in a reasonable compromise between preservation of morphology and maintenance of antigenicity. Finally, an important feature of this approach is that the fluorescence of the GFP signal is preserved throughout the entire preparation process until the last step before electron microscopy.
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Affiliation(s)
- Celine Loussert Fonta
- Electron Microscopy Facility, University of Lausanne, Biophore, 1015 Lausanne, Switzerland.
| | - Andrew Leis
- CSIRO, Australian Animal Health Laboratory, Private Bag 24, Geelong 3220, Australia
| | - Cliff Mathisen
- FEI Company, Achtseweg Noord 5, 5651 GG Eindhoven, The Netherlands
| | - David S Bouvier
- Department of Fundamental Neurosciences, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - Willy Blanchard
- Electron Microscopy Facility, University of Lausanne, Biophore, 1015 Lausanne, Switzerland
| | - Andrea Volterra
- Department of Fundamental Neurosciences, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - Ben Lich
- FEI Company, Achtseweg Noord 5, 5651 GG Eindhoven, The Netherlands
| | - Bruno M Humbel
- Electron Microscopy Facility, University of Lausanne, Biophore, 1015 Lausanne, Switzerland
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