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Shim G, Breinyn IB, Martínez-Calvo A, Rao S, Cohen DJ. Bioelectric stimulation controls tissue shape and size. Nat Commun 2024; 15:2938. [PMID: 38580690 PMCID: PMC10997591 DOI: 10.1038/s41467-024-47079-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 03/20/2024] [Indexed: 04/07/2024] Open
Abstract
Epithelial tissues sheath organs and electro-mechanically regulate ion and water transport to regulate development, homeostasis, and hydrostatic organ pressure. Here, we demonstrate how external electrical stimulation allows us to control these processes in living tissues. Specifically, we electrically stimulate hollow, 3D kidneyoids and gut organoids and find that physiological-strength electrical stimulation of ∼ 5 - 10 V/cm powerfully inflates hollow tissues; a process we call electro-inflation. Electro-inflation is mediated by increased ion flux through ion channels/transporters and triggers subsequent osmotic water flow into the lumen, generating hydrostatic pressure that competes against cytoskeletal tension. Our computational studies suggest that electro-inflation is strongly driven by field-induced ion crowding on the outer surface of the tissue. Electrically stimulated tissues also break symmetry in 3D resulting from electrotaxis and affecting tissue shape. The ability of electrical cues to regulate tissue size and shape emphasizes the role and importance of the electrical micro-environment for living tissues.
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Affiliation(s)
- Gawoon Shim
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, 08540, NJ, USA
| | - Isaac B Breinyn
- Department of Quantitative and Computational Biology, Princeton University, Princeton, 08540, NJ, USA
| | - Alejandro Martínez-Calvo
- Princeton Center for Theoretical Science, Princeton University, Princeton, 08540, NJ, USA
- Department of Chemical and Biological Engineering, Princeton University, Princeton, 08540, NJ, USA
| | - Sameeksha Rao
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, 08540, NJ, USA
| | - Daniel J Cohen
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, 08540, NJ, USA.
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2
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Kang X, Zhang H, Li X, Zhang K, Huang Z, Li Y, Ren X, Chai Y. Electroacupuncture Improving Intestinal Barrier Function in Rats with Irritable Bowel Syndrome Through Regulating Aquaporins. Dig Dis Sci 2024; 69:1143-1155. [PMID: 38421507 DOI: 10.1007/s10620-024-08288-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/07/2024] [Indexed: 03/02/2024]
Abstract
BACKGROUND Intestinal mucosal barrier dysfunction plays a crucial role in the pathogenesis of irritable bowel syndrome with diarrhea (IBS-D). In order to explore the mechanism of electroacupuncture (EA) treatment on intestinal mucosal barrier, this study observed the effect of EA on aquaporins (AQPs), tight junctions (TJs), NF-κB pathway and the gut microbiota in IBS-D rats. METHODS The IBS-D model was established by acetic acid enema combined with chronic restraint method. The effects of EA on the treatment of IBS-D were examined by the abdominal withdrawal reflex score, Bristol's fecal character score, fecal water content, small intestine propulsion rate and HE staining. AQPs, TJs and inflammation-related molecular mechanisms were explored. The fecal samples were applied for 16S rRNA sequencing to assess the effect of EA intervention to the intestinal bacterial abundance. RESULTS EA reduced intestinal sensitization, restored intestinal motility and improved inflammatory cell infiltration. Furthermore, EA improved intestinal inflammation and flora environment significantly, inhibited NF-κB signaling and inflammatory factors (IL-1β and TNF-α). It can also increase the gene and protein expression of AQPs (AQP1, AQP3, and AQP8) and the gene levels of TJs (ZO-1 and Occludin). CONCLUSION EA has an inhibitory effect on the NF-κB signaling pathway, and regulates the proteins of AQP1, AQP3, AQP8, and TJs to restore the balance of water metabolism and intestinal permeability in IBS-D, which also restored the function of the intestinal mucosa by regulating the intestinal flora.
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Affiliation(s)
- Xueling Kang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Honglin Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Xiaying Li
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Kai Zhang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, No. 11 Beisanhuan East Road, Chaoyang District, Beijing, 100029, China
| | - Zhansheng Huang
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Yuanyuan Li
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Xiaoxuan Ren
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Yemao Chai
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, 100029, China.
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Zajac M, Jakiela S, Dolowy K. Understanding Bidirectional Water Transport across Bronchial Epithelial Cell Monolayers: A Microfluidic Approach. MEMBRANES 2023; 13:901. [PMID: 38132905 PMCID: PMC10744786 DOI: 10.3390/membranes13120901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/24/2023] [Accepted: 12/02/2023] [Indexed: 12/23/2023]
Abstract
Deciphering the dynamics of water transport across bronchial epithelial cell monolayers is pivotal for unraveling respiratory physiology and pathology. In this study, we employ an advanced microfluidic system to explore bidirectional water transport across 16HBE14σ bronchial epithelial cells. Previous experiments unveiled electroneutral multiple ion transport, with chloride ions utilizing transcellular pathways and sodium ions navigating both paracellular and transcellular routes. Unexpectedly, under isoosmotic conditions, rapid bidirectional movement of Na+ and Cl- was observed, leading to the hypothesis of a substantial transport of isoosmotic solution (145 mM NaCl) across cell monolayers. To validate this conjecture, we introduce an innovative microfluidic device, offering a 500-fold sensitivity improvement in quantifying fluid flow. This system enables the direct measurement of minuscule fluid volumes traversing cell monolayers with unprecedented precision. Our results challenge conventional models, indicating a self-regulating mechanism governing water transport that involves the CFTR channel and anion exchangers. In healthy subjects, equilibrium is achieved at an apical potential of Δφap = -30 mV, while subjects with cystic fibrosis exhibit modulation by an anion exchanger, reaching equilibrium at [Cl] = 67 mM in the airway surface liquid. This nuanced electrochemical basis for bidirectional water transport in bronchial epithelia sheds light on physiological intricacies and introduces a novel perspective for understanding respiratory conditions.
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Affiliation(s)
- Miroslaw Zajac
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland;
| | | | - Krzysztof Dolowy
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland;
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4
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Lin C, He H, Kim JJ, Zheng X, Huang Z, Dai N. Osmotic pressure induces translocation of aquaporin-8 by P38 and JNK MAPK signaling pathways in patients with functional constipation. Dig Liver Dis 2023; 55:1049-1059. [PMID: 36792433 DOI: 10.1016/j.dld.2023.01.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 12/06/2022] [Accepted: 01/26/2023] [Indexed: 02/17/2023]
Abstract
BACKGROUND Aquaporins (AQPs) maintain fluid homeostasis in the colon. The role of colonic AQPs in the pathophysiology of functional constipation (FC) remains largely unknown. AIM To explore variations in aquaporins and investigate their underlying mechanisms. METHODS Colonic biopsies were collected from patients with FC and healthy controls. The expression and localization of AQPs were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR), western blot analysis, and immunofluorescence assays. Furthermore, osmotic pressure-induced cell model was used in vitro to investigate the potential relationship between AQP8 and osmotic pressure, and to reveal the underlying mechanisms. RESULTS Upregulation of AQP3 and AQP8, and downregulation of AQP1, AQP7, AQP9, AQP10, and AQP11 were observed in the patients with functional constipation. Furthermore, cellular translocation of AQP8 from the cytoplasm to the plasma membrane was observed in patients with FC. Mechanistically, the increase in osmotic pressure could activate the Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) signaling pathways, and subsequently promote the upregulation and translocation of AQP8. CONCLUSION Upregulation of AQP8 and AQP3, and translocation of AQP8 were observed in colon biopsies from patients with FC. The p38 and JNK MAPK signaling pathways are involved in the regulation of osmotic pressure-induced AQP8 variation.
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Affiliation(s)
- Chenhong Lin
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Huiqin He
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - John J Kim
- Division of Gastroenterology & Hepatology, Loma Linda University Health, Loma Linda, CA, United States
| | - Xia Zheng
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhihui Huang
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
| | - Ning Dai
- Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
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Kato S, Inomata H. Blastopore gating mechanism to regulate extracellular fluid excretion. iScience 2023; 26:106585. [PMID: 37192977 PMCID: PMC10182286 DOI: 10.1016/j.isci.2023.106585] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/07/2023] [Accepted: 03/29/2023] [Indexed: 05/18/2023] Open
Abstract
Fluid uptake and efflux play roles in early embryogenesis as well as in adult homeostasis. Multicellular organisms have two main pathways for fluid movement: cellular-level, such as transcellular and paracellular pathways, and tissue-level, involving muscle contraction. Interestingly, early Xenopus embryos with immature functional muscles excrete archenteron fluid via a tissue-level mechanism that opens the blastopore through a gating mechanism that is unclear. Using microelectrodes, we show that the archenteron has a constant fluid pressure and as development progress the blastopore pressure resistance decreases. Combining physical perturbations and imaging analyses, we found that the pushing force exerted by the circumblastoporal collars (CBCs) at the slit periphery regulates pressure resistance. We show that apical constriction at the blastopore dorsoventral ends contributes to this pushing force, and relaxation of ventral constriction causes fluid excretion. These results indicate that actomyosin contraction mediates temporal control of tissue-level blastopore opening and fluid excretion in early Xenopus embryos.
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Affiliation(s)
- Soichiro Kato
- Laboratory for Axial Pattern Dynamics, Center for Biosystems Dynamics Research, RIKEN, Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- Laboratory for Developmental Morphogeometry, Center for Biosystems Dynamics Research, RIKEN, Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Machikaneyama, Toyonaka, Osaka 560-0043, Japan
- Corresponding author
| | - Hidehiko Inomata
- Laboratory for Axial Pattern Dynamics, Center for Biosystems Dynamics Research, RIKEN, Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Machikaneyama, Toyonaka, Osaka 560-0043, Japan
- Corresponding author
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Razzaghi Khamesi P, Charitatos V, Heerfordt EK, MacAulay N, Kurtcuoglu V. Are standing osmotic gradients the main driver of cerebrospinal fluid production? A computational analysis. Fluids Barriers CNS 2023; 20:18. [PMID: 36915140 PMCID: PMC10012606 DOI: 10.1186/s12987-023-00419-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 02/26/2023] [Indexed: 03/14/2023] Open
Abstract
BACKGROUND The mechanisms of cerebrospinal fluid (CSF) production by the ventricular choroid plexus (ChP) have not been fully deciphered. One prominent hypothesized mechanism is trans-epithelial water transport mediated by accumulation of solutes at the luminal ChP membrane that produces local osmotic gradients. However, this standing osmotic gradient hypothesis has not been systematically tested. METHODS To assess the plausibility of the standing gradient mechanism serving as the main driver of CSF production by the ChP, we developed a three-dimensional (3D) and a one-dimensional (1D) computational model to quantitatively describe the associated processes in the rat ChP inter-microvillar spaces and in CSF pools between macroscopic ChP folds (1D only). The computationally expensive 3D model was used to examine the applicability of the 1D model for hypothesis testing. The 1D model was employed to predict the rate of CSF produced by the standing gradient mechanism for 200,000 parameter permutations. Model parameter values for each permutation were chosen by random sampling from distributions derived from published experimental data. RESULTS Both models predict that the CSF production rate by the standing osmotic gradient mechanism is below 10% of experimentally measured values that reflect the contribution of all actual production mechanisms. The 1D model indicates that increasing the size of CSF pools between ChP folds, where diffusion dominates solute transport, would increase the contribution of the standing gradient mechanism to CSF production. CONCLUSIONS The models suggest that the effect of standing osmotic gradients is too small to contribute substantially to CSF production. ChP motion and movement of CSF in the ventricles, which are not accounted for in the models, would further reduce this effect, making it unlikely that standing osmotic gradients are the main drivers of CSF production.
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Affiliation(s)
- Pooya Razzaghi Khamesi
- The Interface Group, Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Vasileios Charitatos
- The Interface Group, Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Eva K Heerfordt
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Nanna MacAulay
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Vartan Kurtcuoglu
- The Interface Group, Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland. .,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland. .,Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland.
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Bhend ME, Kempuraj D, Sinha NR, Gupta S, Mohan RR. Role of aquaporins in corneal healing post chemical injury. Exp Eye Res 2023; 228:109390. [PMID: 36696947 PMCID: PMC9975064 DOI: 10.1016/j.exer.2023.109390] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/31/2022] [Accepted: 01/19/2023] [Indexed: 01/23/2023]
Abstract
Aquaporins (AQPs) are transmembrane water channel proteins that regulate the movement of water through the plasma membrane in various tissues including cornea. The cornea is avascular and has specialized microcirculatory mechanisms for homeostasis. AQPs regulate corneal hydration and transparency for normal vision. Currently, there are 13 known isoforms of AQPs that can be subclassified as orthodox AQPs, aquaglyceroporins (AQGPs), or supraquaporins (SAQPs)/unorthodox AQPs. AQPs are implicated in keratocyte function, inflammation, edema, angiogenesis, microvessel proliferation, and the wound-healing process in the cornea. AQPs play an important role in wound healing by facilitating the movement of corneal stromal keratocytes by squeezing through tight stromal matrix and narrow extracellular spaces to the wound site. Deficiency of AQPs can cause reduced concentration of hepatocyte growth factor (HGF) leading to reduced epithelial proliferation, reduced/impaired keratocyte migration, reduced number of keratocytes in the injury site, delayed and abnormal wound healing process. Dysregulated AQPs cause dysfunction in osmolar homeostasis as well as wound healing mechanisms. The cornea is a transparent avascular tissue that constitutes the anterior aspect of the outer covering of the eye and aids in two-thirds of visual light refraction. Being the outermost layer of the eye, the cornea is prone to injury. Of the 13 AQP isoforms, AQP1 is expressed in the stromal keratocytes and endothelial cells, and AQP3 and AQP5 are expressed in epithelial cells in the human cornea. AQPs can facilitate wound healing through aid in cellular migration, proliferation, migration, extracellular matrix (ECM) remodeling and autophagy mechanism. Corneal wound healing post-chemical injury requires an integrative and coordinated activity of the epithelium, stromal keratocytes, endothelium, ECM, and a battery of cytokines and growth factors to restore corneal transparency. If the chemical injury is mild, the cornea will heal with normal clarity, but severe injuries can lead to partial and/or permanent loss of corneal functions. Currently, the role of AQPs in corneal wound healing is poorly understood in the context of chemical injury. This review discusses the current literature and the role of AQPs in corneal homeostasis, wound repair, and potential therapeutic target for acute and chronic corneal injuries.
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Affiliation(s)
- Madeline E Bhend
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; School of Medicine, University of South Carolina, Columbia, SC, USA; Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Duraisamy Kempuraj
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Nishant R Sinha
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
| | - Suneel Gupta
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
| | - Rajiv R Mohan
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA; Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO, USA.
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Zeng J, Schmitz F, Isaksson S, Glas J, Arbab O, Andersson M, Sundell K, Eriksson LA, Swaminathan K, Törnroth-Horsefield S, Hedfalk K. High-resolution structure of a fish aquaporin reveals a novel extracellular fold. Life Sci Alliance 2022; 5:5/12/e202201491. [PMID: 36229063 PMCID: PMC9559756 DOI: 10.26508/lsa.202201491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 09/21/2022] [Accepted: 09/22/2022] [Indexed: 11/24/2022] Open
Abstract
The structural and functional characterization of a fish AQP reveals a water-specific AQP with unique structural features that may have implications for channel gating in response to osmotic changes. Aquaporins are protein channels embedded in the lipid bilayer in cells from all organisms on earth that are crucial for water homeostasis. In fish, aquaporins are believed to be important for osmoregulation; however, the molecular mechanism behind this is poorly understood. Here, we present the first structural and functional characterization of a fish aquaporin; cpAQP1aa from the fresh water fish climbing perch (Anabas testudineus), a species that is of high osmoregulatory interest because of its ability to spend time in seawater and on land. These studies show that cpAQP1aa is a water-specific aquaporin with a unique fold on the extracellular side that results in a constriction region. Functional analysis combined with molecular dynamic simulations suggests that phosphorylation at two sites causes structural perturbations in this region that may have implications for channel gating from the extracellular side.
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Affiliation(s)
- Jiao Zeng
- Department of Biological Sciences, National University of Singapore, Queenstown, Singapore
| | - Florian Schmitz
- Department and Chemistry and Molecular Biology, Gothenburg University, Göteborg, Sweden
| | - Simon Isaksson
- Department of Chemistry and Chemical Engineering, Applied Surface Chemistry, Chalmers University of Technology, Gothenburg, Sweden
| | - Jessica Glas
- Department and Chemistry and Molecular Biology, Gothenburg University, Göteborg, Sweden
| | - Olivia Arbab
- Department and Chemistry and Molecular Biology, Gothenburg University, Göteborg, Sweden
| | - Martin Andersson
- Department of Chemistry and Chemical Engineering, Applied Surface Chemistry, Chalmers University of Technology, Gothenburg, Sweden
| | - Kristina Sundell
- Department of Biology and Environmental Sciences, Gothenburg University, Göteborg, Sweden
| | - Leif A Eriksson
- Department and Chemistry and Molecular Biology, Gothenburg University, Göteborg, Sweden
| | | | - Susanna Törnroth-Horsefield
- Department of Biochemistry and Structural Biology, Centre for Molecular Protein Science, Lund University, Lund, Sweden
| | - Kristina Hedfalk
- Department and Chemistry and Molecular Biology, Gothenburg University, Göteborg, Sweden
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Kon R, Ikarashi N, Onuma K, Yasukawa Z, Ozeki M, Sakai H, Kamei J. Effect of partially hydrolyzed guar gum on the expression of aquaporin-3 in the colon. Food Sci Nutr 2022; 11:1127-1133. [PMID: 36789055 PMCID: PMC9922137 DOI: 10.1002/fsn3.3150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/29/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022] Open
Abstract
In recent years, the development of functional foods targeting gastrointestinal disorders has been in progress. Partially hydrolyzed guar gum (PHGG), which is a water-soluble dietary fiber, is known to have a constipation-improving effect. However, many aspects of the mechanism remain unclear. In this study, we investigated the role of aquaporin-3 (AQP3), which regulates the water content of feces in ameliorative effect of PHGG on constipation. Rats were allowed to freely consume a normal diet or a diet containing 5% PHGG for 14 days, and defecation parameters were measured. We also analyzed the expression levels of genes involved in water transport in the colon. The defecation frequency and volume of rats treated with PHGG were not different from those from the control group, but the fecal water content was significantly increased, and soft stools were observed. The expressions of claudin-1, tight junction protein-1, and cadherin-1, which are involved in tight junctions or adherens junctions, were almost the same in the PHGG-treated group and the control group. The expression level of AQP3 in the colon was significantly decreased in the PHGG-treated group. In this study, PHGG decreased the colonic AQP3 expression, thereby suppressing water transport from the luminal side to the vascular side and improving constipation.
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Affiliation(s)
- Risako Kon
- Department of Biomolecular PharmacologyHoshi UniversityTokyoJapan
| | | | - Kazuhiro Onuma
- Department of Biomolecular PharmacologyHoshi UniversityTokyoJapan
| | - Zenta Yasukawa
- Department of Nutrition, Faculty of NutritionKanazawa Gakuin UniversityIshikawaJapan
| | | | - Hiroyasu Sakai
- Department of Biomolecular PharmacologyHoshi UniversityTokyoJapan
| | - Junzo Kamei
- Advanced Research Institute for Health ScienceJuntendo UniversityTokyoJapan
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10
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Chugh M, Munjal A, Megason SG. Hydrostatic pressure as a driver of cell and tissue morphogenesis. Semin Cell Dev Biol 2022; 131:134-145. [PMID: 35534334 PMCID: PMC9529827 DOI: 10.1016/j.semcdb.2022.04.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/24/2022] [Accepted: 04/27/2022] [Indexed: 12/14/2022]
Abstract
Morphogenesis, the process by which tissues develop into functional shapes, requires coordinated mechanical forces. Most current literature ascribes contractile forces derived from actomyosin networks as the major driver of tissue morphogenesis. Recent works from diverse species have shown that pressure derived from fluids can generate deformations necessary for tissue morphogenesis. In this review, we discuss how hydrostatic pressure is generated at the cellular and tissue level and how the pressure can cause deformations. We highlight and review findings demonstrating the mechanical roles of pressures from fluid-filled lumens and viscous gel-like components of the extracellular matrix. We also emphasise the interactions and mechanochemical feedbacks between extracellular pressures and tissue behaviour in driving tissue remodelling. Lastly, we offer perspectives on the open questions in the field that will further our understanding to uncover new principles of tissue organisation during development.
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Affiliation(s)
- Mayank Chugh
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
| | - Akankshi Munjal
- Department of Cell Biology, Duke University School of Medicine, Nanaline Duke Building, 307 Research Drive, Durham, NC 27710, USA.
| | - Sean G Megason
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
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Chmiel TA, Gardel ML. Confluence and tight junction dependence of volume regulation in epithelial tissue. Mol Biol Cell 2022; 33:ar98. [PMID: 35731553 DOI: 10.1091/mbc.e22-03-0073] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Epithelial cell volume regulation is a key component to tissue stability and dynamics. In particular, how cells respond to osmotic stresses is of significant physiological interest in kidney epithelial tissue. For individual mammalian cells, it is well established that Na-K-2Cl cotransporter (NKCC) channels mediate cell volume homeostasis in response to hyperosmotic stress. However, whether mature epithelium responds similarly is not well known. Here we show that while small colonies of madin darby canine kidney (MDCK) epithelial cells behave similarly to single cells and exhibit volume homeostasis that is dependent on the NKCC channel function, mature epithelial tissue does not. Instead, the cell volume decreases by 33% when confluent monolayers or acini formed from MDCK cells are subjected to hyperosmotic stress. We show that the tight junction protein zonula occludins-1 (ZO-1), and Rho-associated kinase (ROCK) are essential for osmotic regulation of cell volume in mature epithelium. Because these both are known to be essential for tight junction assembly, this strongly suggests a role for tight junctions in changing volume response in mature epithelium. Thus, tight junctions act either directly or indirectly in osmotic pressure response of epithelial tissue to suppress volume homeostasis common to isolated epithelial cells.
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Affiliation(s)
- Theresa A Chmiel
- Institute for Biophysical Dynamics, James Franck Institute, Department of Physics, Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637
| | - Margaret L Gardel
- Institute for Biophysical Dynamics, James Franck Institute, Department of Physics, Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637
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12
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Liu S, Qiu Y, Gu F, Xu X, Wu S, Jin Z, Wang L, Gao K, Zhu C, Yang X, Jiang Z. Niacin Improves Intestinal Health through Up-Regulation of AQPs Expression Induced by GPR109A. Int J Mol Sci 2022; 23:ijms23158332. [PMID: 35955466 PMCID: PMC9368703 DOI: 10.3390/ijms23158332] [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: 07/08/2022] [Revised: 07/26/2022] [Accepted: 07/26/2022] [Indexed: 11/22/2022] Open
Abstract
(1) Background: Changes in the expression of aquaporins (AQPs) in the intestine are proved to be associated with the attenuation of diarrhea. Diarrhea is a severe problem for postweaning piglets. Therefore, this study aimed to investigate whether niacin could alleviate diarrhea in weaned piglets by regulating AQPs expression and the underlying mechanisms; (2) Methods: 72 weaned piglets (Duroc × (Landrace × Yorkshire), 21 d old, 6.60 ± 0.05 kg) were randomly allotted into 3 groups for a 14-day feeding trial. Each treatment group included 6 replicate pens and each pen included 4 barrows (n = 24/treatment). Piglets were fed a basal diet (CON), a basal diet supplemented with 20.4 mg niacin/kg diet (NA) or the basal diet administered an antagonist for the GPR109A receptor (MPN). Additionally, an established porcine intestinal epithelial cell line (IPEC-J2) was used to investigate the protective effects and underlying mechanism of niacin on AQPs expression after Escherichia coli K88 (ETEC K88) treatment; (3) Results: Piglets fed niacin-supplemented diet had significantly decreased diarrhea rate, and increased mRNA and protein level of ZO-1, AQP 1 and AQP 3 in the colon compared with those administered a fed diet supplemented with an antagonist (p < 0.05). In addition, ETEC K88 treatment significantly reduced the cell viability, cell migration, and mRNA and protein expression of AQP1, AQP3, AQP7, AQP9, AQP11, and GPR109A in IPEC-J2 cells (p < 0.05). However, supplementation with niacin significantly prevented the ETEC K88-induced decline in the cell viability, cell migration, and the expression level of AQPs mRNA and protein in IPEC-J2 cells (p < 0.05). Furthermore, siRNA GPR109A knockdown significantly abrogated the protective effect of niacin on ETEC K88-induced cell damage (p < 0.05); (4) Conclusions: Niacin supplementation increased AQPs and ZO-1 expression to reduce diarrhea and intestinal damage through GPR109A pathway in weaned piglets.
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13
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Targeting choroid plexus epithelium as a novel therapeutic strategy for hydrocephalus. J Neuroinflammation 2022; 19:156. [PMID: 35715859 PMCID: PMC9205094 DOI: 10.1186/s12974-022-02500-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 06/01/2022] [Indexed: 11/25/2022] Open
Abstract
The choroid plexus is a tissue located in the lateral ventricles of the brain and is composed mainly of choroid plexus epithelium cells. The main function is currently thought to be the secretion of cerebrospinal fluid and the regulation of its pH, and more functions are gradually being demonstrated. Assistance in the removal of metabolic waste and participation in the apoptotic pathway are also the functions of choroid plexus. Besides, it helps to repair the brain by regulating the secretion of neuropeptides and the delivery of drugs. It is involved in the immune response to assist in the clearance of infections in the central nervous system. It is now believed that the choroid plexus is in an inflammatory state after damage to the brain. This state, along with changes in the cilia, is thought to be an abnormal physiological state of the choroid plexus, which in turn leads to abnormal conditions in cerebrospinal fluid and triggers hydrocephalus. This review describes the pathophysiological mechanism of hydrocephalus following choroid plexus epithelium cell abnormalities based on the normal physiological functions of choroid plexus epithelium cells, and analyzes the attempts and future developments of using choroid plexus epithelium cells as a therapeutic target for hydrocephalus.
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14
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Peters WS, Knoblauch M. How Münch's adaptation of Pfeffer's circulating water flow became the pressure-flow theory, and the resulting problems - A historical perspective. JOURNAL OF PLANT PHYSIOLOGY 2022; 272:153672. [PMID: 35366573 DOI: 10.1016/j.jplph.2022.153672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Long-distance transport of photoassimilates in the phloem of vascular plants occurs as bulk flow in sieve tubes. These tubes are arrays of cells that lose nuclei, cytoskeleton, and some organelles when they differentiate into mature sieve elements. Symplasmic continuity is achieved by perforations that turn the cell walls between adjoining sieve elements into sieve plates. These structural features are interpreted as adaptations that reduce the resistance sieve tubes offer to cytoplasmic bulk flow. According to the common reading of Ernst Münch's pressure-flow theory, the driving forces for these flows are osmotically generated gradients of hydrostatic pressure along the sieve tubes. However, the significance of pressure gradients in the flow direction has also been questioned. Münch himself stated that no detectable pressure gradients existed between the linked osmotic cells that he used to demonstrate the validity of his ideas, and the earliest explanation of osmotically driven flows by Wilhelm Pfeffer, on which Münch based his theory, explicitly claimed the absence of pressure gradients. To resolve the apparent contradiction, we here reconstruct the history of the idea that osmotically driven transport processes in organisms necessarily require steps or gradients of hydrostatic pressure along the transport route. Our analysis leads us to conclude that some defects of overly simplifying interpretations of Münch's ideas (such as the sieve plate fallacy) could be avoided if our descriptions of his theory in textbooks and the scientific literature would follow the logics of the theory's earliest formulations more closely.
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Affiliation(s)
- Winfried S Peters
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA; Department of Biology, Purdue University Fort Wayne, Fort Wayne, IN, 46805, USA.
| | - Michael Knoblauch
- School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA.
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15
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Deguchi H, Yamashita T, Hiramoto N, Otsuki Y, Mukai A, Ueno M, Sotozono C, Kinoshita S, Hamuro J. Intracellular pH affects mitochondrial homeostasis in cultured human corneal endothelial cells prepared for cell injection therapy. Sci Rep 2022; 12:6263. [PMID: 35428816 PMCID: PMC9012833 DOI: 10.1038/s41598-022-10176-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/30/2022] [Indexed: 12/11/2022] Open
Abstract
This study aimed to uncover the mechanism responsible for the clinical efficacy of cell injection therapy with fully differentiated cultured cells. Analysis of polarized expression of ion transporters on cultured human corneal endothelial cells (CECs) subpopulations (SPs) was performed. The intracellular pH (pHi) between two CEC SPs, distinct in the proportion of differentiated cells, was measured, and the association with mitochondrial respiration homeostasis was investigated. The effects of the ion transporter inhibition by their selective inhibitors or siRNA transfection were also explored. Na+/K+-ATPase, Aquaporin 1, SLC4A11, NBCe1, NHE1 as transporters, and ZO-1, were all selectively expressed in differentiated SPs, but were almost null in the cell-state-transitioned SPs. We also confirmed that the pHi of CEC SPs affected their mitochondrial respiration by modulating the expression of these ion transporters via inhibitors or siRNA transfection. Ion and water transporters might participate in the maintenance of pHi and mitochondria homeostasis in differentiated SPs, which may contribute, combined with integral barrier functions, to efficient water efflux. The differences in intracellular pH between the two SPs is attributed to variations in the expression profile of specific ion transporters and mitochondrial functions, which may associate with the efficacy of the SPs in cell injection therapy.
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Affiliation(s)
- Hideto Deguchi
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Tomoko Yamashita
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Nao Hiramoto
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Yohei Otsuki
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Atsushi Mukai
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Morio Ueno
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Chie Sotozono
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan
| | - Shigeru Kinoshita
- Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Junji Hamuro
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Hirokoji-agaru, Kawaramachi-dori, Kamigyo-ku, Kyoto, 602-0841, Japan.
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16
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MacAulay N, Keep RF, Zeuthen T. Cerebrospinal fluid production by the choroid plexus: a century of barrier research revisited. Fluids Barriers CNS 2022; 19:26. [PMID: 35317823 PMCID: PMC8941821 DOI: 10.1186/s12987-022-00323-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/09/2022] [Indexed: 12/20/2022] Open
Abstract
Cerebrospinal fluid (CSF) envelops the brain and fills the central ventricles. This fluid is continuously replenished by net fluid extraction from the vasculature by the secretory action of the choroid plexus epithelium residing in each of the four ventricles. We have known about these processes for more than a century, and yet the molecular mechanisms supporting this fluid secretion remain unresolved. The choroid plexus epithelium secretes its fluid in the absence of a trans-epithelial osmotic gradient, and, in addition, has an inherent ability to secrete CSF against an osmotic gradient. This paradoxical feature is shared with other 'leaky' epithelia. The assumptions underlying the classical standing gradient hypothesis await experimental support and appear to not suffice as an explanation of CSF secretion. Here, we suggest that the elusive local hyperosmotic compartment resides within the membrane transport proteins themselves. In this manner, the battery of plasma membrane transporters expressed in choroid plexus are proposed to sustain the choroidal CSF secretion independently of the prevailing bulk osmotic gradient.
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Affiliation(s)
- Nanna MacAulay
- Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen, Denmark.
| | - Richard F Keep
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA
| | - Thomas Zeuthen
- Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200, Copenhagen, Denmark
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17
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Torres-Sánchez A, Winter MK, Salbreux G. Tissue hydraulics: Physics of lumen formation and interaction. Cells Dev 2021; 168:203724. [PMID: 34339904 DOI: 10.1016/j.cdev.2021.203724] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/08/2021] [Accepted: 07/20/2021] [Indexed: 11/29/2022]
Abstract
Lumen formation plays an essential role in the morphogenesis of tissues during development. Here we review the physical principles that play a role in the growth and coarsening of lumens. Solute pumping by the cell, hydraulic flows driven by differences of osmotic and hydrostatic pressures, balance of forces between extracellular fluids and cell-generated cytoskeletal forces, and electro-osmotic effects have been implicated in determining the dynamics and steady-state of lumens. We use the framework of linear irreversible thermodynamics to discuss the relevant force, time and length scales involved in these processes. We focus on order of magnitude estimates of physical parameters controlling lumen formation and coarsening.
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Affiliation(s)
| | - Max Kerr Winter
- The Francis Crick Institute, 1 Midland Road, NW1 1AT, United Kingdom
| | - Guillaume Salbreux
- The Francis Crick Institute, 1 Midland Road, NW1 1AT, United Kingdom; University of Geneva, Quai Ernest Ansermet 30, 1205 Genève, Switzerland.
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18
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Lv H, Li Y, Xue C, Dong N, Bi C, Shan A. Aquaporin: targets for dietary nutrients to regulate intestinal health. J Anim Physiol Anim Nutr (Berl) 2021; 106:167-180. [PMID: 33811387 DOI: 10.1111/jpn.13539] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 12/07/2020] [Accepted: 02/07/2021] [Indexed: 12/22/2022]
Abstract
Aquaporins (AQP) are a class of water channel membrane proteins that are widely expressed in the gut. The biological functions of aquaporins, which regulate the absorption and secretion of water molecules and small solutes, maintain the stable state of the intestine, regulate cell proliferation and migration, participate in the process of intestinal inflammation, and mediate tumorigenesis, demonstrate the physiological significance of these channels in intestinal health. The pathology of many intestinal diseases is associated with changes in the location and expression of aquaporins, such as intestinal infection, which can change the expression and distribution of AQPs in intestinal tissues/cells by affecting cytokines and chemokines. This can lead to various intestinal diseases such as diarrhoea, which also suggests the importance of aquaporins in the prevention and treatment of intestinal diseases. This review summarizes the relationship between aquaporins and intestinal physiology and diseases and focuses on drugs (such as plant extracts) or diets that can regulate intestinal health by regulating aquaporins. It provides a basis for establishing aquaporins as biomarkers and therapeutic targets for intestinal health.
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Affiliation(s)
- Hao Lv
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
| | - Ying Li
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
| | - Chenyu Xue
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
| | - Na Dong
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
| | - Chongpeng Bi
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
| | - Anshan Shan
- Institute of Animal Nutrition, Northeast Agricultural University, Harbin, China
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19
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Angulin-2/ILDR1, a tricellular tight junction protein, does not affect water transport in the mouse large intestine. Sci Rep 2020; 10:10374. [PMID: 32587380 PMCID: PMC7316798 DOI: 10.1038/s41598-020-67319-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 04/23/2020] [Indexed: 11/09/2022] Open
Abstract
Angulin-2/ILDR1 is a member of the angulin protein family, which is exclusively expressed at tricellular tight junctions in epithelia. Tricellular tight junctions are found where three cells meet and where three bicellular tight junction strands converge. Tricellular tight junctions are thought to be important for paracellular permeability of ions and water in epithelial tissues. It was recently reported that angulin-2/ILDR1 knockout mice have water transport abnormalities in the kidney. Since angulin-2/ILDR1 is the main tricellular tight junction protein in the large intestine, the goal of this research was to examine the effect of angulin-2/ILDR1 knockout on large intestinal paracellular water transport. We found that Ildr1 knockout mice showed no detectable phenotype other than deafness. In addition, paracellular transport as assessed by Ussing chamber was unchanged in Ildr1 knockout mice. However, we found that in the colon and the kidney of Ildr1 knockout mice, another tricellular tight junction protein, angulin-1/LSR, changes its expression pattern. We propose that with this replacement in tissue localization, angulin-1/LSR compensates for the loss of angulin-2/ILDR1 and maintains the barrier and function of the epithelia in the large intestine as well as the kidney.
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20
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Amador-Muñoz D, Gutiérrez ÁM, Payán-Gómez C, Matheus LM. In silico and in vitro analysis of cation-activated potassium channels in human corneal endothelial cells. Exp Eye Res 2020; 197:108114. [PMID: 32561484 DOI: 10.1016/j.exer.2020.108114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/02/2020] [Accepted: 06/07/2020] [Indexed: 12/31/2022]
Abstract
The corneal endothelium is the inner cell monolayer involved in the maintenance of corneal transparence by the generation of homeostatic dehydration. The glycosaminoglycans of the corneal stroma develop a continuous swelling pressure that should be counteracted by the corneal endothelial cells through active transport mechanisms to move the water to the anterior chamber. Protein transporters for sodium (Na+), potassium (K+), chloride (Cl-) and bicarbonate (HCO3-) are involved in this endothelial "pump function", however despite its physiological importance, the efflux mechanism is not completely understood. There is experimental evidence describing transendothelial diffusion of water in the absence of osmotic gradients. Therefore, it is important to get a deeper understanding of alternative models that drive the fluid transport across the endothelium such as the electrochemical gradients. Three transcriptomic datasets of the corneal endothelium were used in this study to analyze the expression of genes that encode proteins that participate in the transport and the reestablishment of the membrane potential across the semipermeable endothelium. Subsequently, the expression of the identified channels was validated in vitro both at mRNA and protein levels. The results of this study provide the first evidence of the expression of KCNN2, KCNN3 and KCNT2 genes in the corneal endothelium. Differences among the level of expression of KCNN2, KCNT2 and KCNN4 genes were found in a differentially expressed gene analysis of the dataset. Taken together these results underscore the potential importance of the ionic channels in the pathophysiology of corneal diseases. Moreover, we elucidate novel mechanisms that might be involved in the pivotal dehydrating function of the endothelium and in others physiologic functions of these cells using in silico pathways analysis.
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Affiliation(s)
- Diana Amador-Muñoz
- Neuroscience (NEUROS) Research Group, School of Medicine and Health Sciences, Universidad del Rosario, Carrera 24 No. 63 C 69, P.O 111221, Bogotá, Colombia.
| | - Ángela María Gutiérrez
- Escuela Superior de Oftalmología, Instituto Barraquer de América, Calle 100 No. 18 A 51, Bogotá, Colombia.
| | - César Payán-Gómez
- Department of Biology, Faculty of Natural Sciences, Universidad del Rosario, Carrera 24 No. 63 C 69, Bogotá, P.O 111221, Colombia.
| | - Luisa Marina Matheus
- Neuroscience (NEUROS) Research Group, School of Medicine and Health Sciences, Universidad del Rosario, Carrera 24 No. 63 C 69, P.O 111221, Bogotá, Colombia.
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21
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Máiz Carro L, Martínez-García MA. Nebulized hypertonic saline in noncystic fibrosis bronchiectasis: a comprehensive review. Ther Adv Respir Dis 2020; 13:1753466619866102. [PMID: 31390940 PMCID: PMC6688147 DOI: 10.1177/1753466619866102] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Bronchiectasis occurs as a result of a vicious circle consisting of an impaired mucociliary transport system, inflammation, and infection and repair of the airways. Damage to the mucociliary system prevents secretion elimination and facilitates bacterial growth and bronchial inflammation. To facilitate mucociliary clearance, current guidelines recommend the use of hypertonic saline (HS) solutions in patients with bronchiectasis not secondary to cystic fibrosis (CF), although the evidence of efficacy in this pathology is sparse. A high percentage of patients with CF and bronchiectasis tolerate HS solutions, but often patients report cough, dyspnoea, throat irritation, or salty taste after inhalation. These adverse effects negatively impact adherence to treatment, which sometimes must be discontinued. Some studies have shown that the addition of hyaluronic acid increases the tolerability of HS solutions, both in patients with CF and in bronchiectasis of other etiologies. We aimed to review the benefits and safety of HS solutions in patients with bronchiectasis. The reviews of this paper are available via the supplemental material section.
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Affiliation(s)
- Luis Máiz Carro
- Chronic Bronchial Infection, Cystic Fibrosis and Bronchiectasis Unit, Ramón y Cajal University Hospital, Ctra. Colmenar Viejo, km. 9,100, Madrid 28034, Spain
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22
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Tipsmark CK, Nielsen AM, Bossus MC, Ellis LV, Baun C, Andersen TL, Dreier J, Brewer JR, Madsen SS. Drinking and Water Handling in the Medaka Intestine: A Possible Role of Claudin-15 in Paracellular Absorption? Int J Mol Sci 2020; 21:ijms21051853. [PMID: 32182691 PMCID: PMC7085193 DOI: 10.3390/ijms21051853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 12/27/2022] Open
Abstract
When euryhaline fish move between fresh water (FW) and seawater (SW), the intestine undergoes functional changes to handle imbibed SW. In Japanese medaka, the potential transcellular aquaporin-mediated conduits for water are paradoxically downregulated during SW acclimation, suggesting paracellular transport to be of principal importance in hyperosmotic conditions. In mammals, intestinal claudin-15 (CLDN15) forms paracellular channels for small cations and water, which may participate in water transport. Since two cldn15 paralogs, cldn15a and cldn15b, have previously been identified in medaka, we examined the salinity effects on their mRNA expression and immunolocalization in the intestine. In addition, we analyzed the drinking rate and intestinal water handling by adding non-absorbable radiotracers, 51-Cr-EDTA or 99-Tc-DTPA, to the water. The drinking rate was >2-fold higher in SW than FW-acclimated fish, and radiotracer experiments showed anterior accumulation in FW and posterior buildup in SW intestines. Salinity had no effect on expression of cldn15a, while cldn15b was approximately 100-fold higher in FW than SW. Despite differences in transcript dynamics, Cldn15a and Cldn15b proteins were both similarly localized in the apical tight junctions of enterocytes, co-localizing with occludin and with no apparent difference in localization and abundance between FW and SW. The stability of the Cldn15 protein suggests a physiological role in water transport in the medaka intestine.
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Affiliation(s)
- Christian K. Tipsmark
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA; (M.C.B.); (L.V.E.); (S.S.M.)
- Correspondence: ; Tel.: +1-479-575-8436
| | - Andreas M. Nielsen
- Department of Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark;
| | - Maryline C. Bossus
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA; (M.C.B.); (L.V.E.); (S.S.M.)
- Department of Math and Sciences, Lyon College, 2300 Highland Rd, Batesville, AR 72501, USA
| | - Laura V. Ellis
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA; (M.C.B.); (L.V.E.); (S.S.M.)
| | - Christina Baun
- Department of Nuclear Medicine, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense C, Denmark; (C.B.); (T.L.A.)
| | - Thomas L. Andersen
- Department of Nuclear Medicine, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense C, Denmark; (C.B.); (T.L.A.)
| | - Jes Dreier
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark; (J.D.); (J.R.B.)
| | - Jonathan R. Brewer
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark; (J.D.); (J.R.B.)
| | - Steffen S. Madsen
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA; (M.C.B.); (L.V.E.); (S.S.M.)
- Department of Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark;
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23
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Carrageta DF, Bernardino RL, Alves MG, Oliveira PF. CFTR regulation of aquaporin-mediated water transport. VITAMINS AND HORMONES 2020; 112:163-177. [PMID: 32061340 DOI: 10.1016/bs.vh.2019.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel responsible for the direct transport of bicarbonate and chloride. CFTR-dependent ionic transport is crucial for pH regulation and fluid homeodynamics among epithelial surfaces. Particularly, CFTR performs an essential role in the male reproductive tract, which requires a tight regulation of water and electrolytes in order to produce healthy spermatozoa. The absence or malfunction of CFTR results in cystic fibrosis, the most common lethal disease among Caucasians, that is characterized by an impaired fluid and ionic homeostasis in the whole organism. Due to the wide expression and importance of CFTR, the male reproductive tract is highly affected by cystic fibrosis, resulting in male infertility. Although CFTR is not permeable to water, this protein acts as a regulator of other protein channels, such as aquaporins. In fact, CFTR acts as a molecular partner of aquaporins in epithelial cells, regulating fluid homeodynamics. Herein, up-to-date data concerning the regulation of aquaporin-mediated water transport by CFTR will be discussed, highlighting the role of both channels in the male reproductive tract.
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Affiliation(s)
- David F Carrageta
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Raquel L Bernardino
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal; Department of Genetics, Faculty of Medicine, University of Porto, Porto, Portugal; i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
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24
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Mosaliganti KR, Swinburne IA, Chan CU, Obholzer ND, Green AA, Tanksale S, Mahadevan L, Megason SG. Size control of the inner ear via hydraulic feedback. eLife 2019; 8:39596. [PMID: 31571582 PMCID: PMC6773445 DOI: 10.7554/elife.39596] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 08/26/2019] [Indexed: 01/05/2023] Open
Abstract
Animals make organs of precise size, shape, and symmetry but how developing embryos do this is largely unknown. Here, we combine quantitative imaging, physical theory, and physiological measurement of hydrostatic pressure and fluid transport in zebrafish to study size control of the developing inner ear. We find that fluid accumulation creates hydrostatic pressure in the lumen leading to stress in the epithelium and expansion of the otic vesicle. Pressure, in turn, inhibits fluid transport into the lumen. This negative feedback loop between pressure and transport allows the otic vesicle to change growth rate to control natural or experimentally-induced size variation. Spatiotemporal patterning of contractility modulates pressure-driven strain for regional tissue thinning. Our work connects molecular-driven mechanisms, such as osmotic pressure driven strain and actomyosin tension, to the regulation of tissue morphogenesis via hydraulic feedback to ensure robust control of organ size. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
| | - Ian A Swinburne
- Department of Systems Biology, Harvard Medical School, Boston, United States
| | - Chon U Chan
- School of Engineering and Applied Sciences, Harvard University, Cambridge, United States
| | - Nikolaus D Obholzer
- Department of Systems Biology, Harvard Medical School, Boston, United States
| | - Amelia A Green
- Department of Systems Biology, Harvard Medical School, Boston, United States
| | - Shreyas Tanksale
- Department of Systems Biology, Harvard Medical School, Boston, United States
| | - L Mahadevan
- School of Engineering and Applied Sciences, Harvard University, Cambridge, United States.,Department of Organismal and Evolutionary Biology, Harvard University, Cambridge, United States.,Department of Physics, Harvard University, Cambridge, United States.,Kavli Institute for NanoBio Science and Technology, Harvard University, Cambridge, United States
| | - Sean G Megason
- Department of Systems Biology, Harvard Medical School, Boston, United States
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25
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Wu NC, McKercher C, Cramp RL, Franklin CE. Mechanistic basis for loss of water balance in green tree frogs infected with a fungal pathogen. Am J Physiol Regul Integr Comp Physiol 2019; 317:R301-R311. [PMID: 31141416 DOI: 10.1152/ajpregu.00355.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Chytridiomycosis, a lethal skin disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), disrupts skin function of amphibians, interfering with ionic and osmotic regulation. To regulate fungal loads, amphibians increase their rate of skin sloughing. However, sloughing also causes a temporary loss of ionic and osmotic homeostasis due to disruption of the skin, a key osmoregulatory organ. The combined effects of increased sloughing frequency and chytridiomycosis contribute to the high rates of mortality from Bd infections. However, the mechanisms responsible for the loss of cutaneous osmotic regulation remain unknown. We measured the changes in whole animal water uptake rates, in vitro transcutaneous water fluxes across the ventral skin, and the mRNA expression of epithelial water transport proteins (aquaporins, AQPs) and junctional proteins in Bd-infected and uninfected Litoria caerulea skin. We hypothesize that infected frogs would show reduction/inhibition in cutaneous water transporters responsible for regulating water balance, and sloughing would exacerbate cutaneous water fluxes. We found that infected, nonsloughing frogs had an impaired rate of water uptake and showed increased rates of in vitro water efflux across the ventral skin. In uninfected frogs, the expression of AQPs and junction genes increased significantly with sloughing, which may assist in regulating cutaneous water movements and barrier function in the newly exposed skin. In contrast, infected frogs did not show this postsloughing increase in AQP gene expression. The combination of increased sloughing frequency, impaired water uptake rates, and increased rates of water loss likely contributes to the loss of osmotic homeostasis in frogs infected with Bd.
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Affiliation(s)
- Nicholas C Wu
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Callum McKercher
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Rebecca L Cramp
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Craig E Franklin
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
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26
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ZEB1 insufficiency causes corneal endothelial cell state transition and altered cellular processing. PLoS One 2019; 14:e0218279. [PMID: 31194824 PMCID: PMC6564028 DOI: 10.1371/journal.pone.0218279] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/29/2019] [Indexed: 12/13/2022] Open
Abstract
The zinc finger e-box binding homeobox 1 (ZEB1) transcription factor is a master regulator of the epithelial to mesenchymal transition (EMT), and of the reverse mesenchymal to epithelial transition (MET) processes. ZEB1 plays an integral role in mediating cell state transitions during cell lineage specification, wound healing and disease. EMT/MET are characterized by distinct changes in molecular and cellular phenotype that are generally context-independent. Posterior polymorphous corneal dystrophy (PPCD), associated with ZEB1 insufficiency, provides a new biological context in which to understand and evaluate the classic EMT/MET paradigm. PPCD is characterized by a cadherin-switch and transition to an epithelial-like transcriptomic and cellular phenotype, which we study in a cell-based model of PPCD generated using CRISPR-Cas9-mediated ZEB1 knockout in corneal endothelial cells (CEnCs). Transcriptomic and functional studies support the hypothesis that CEnC undergo a MET-like transition in PPCD, termed endothelial to epithelial transition (EnET), and lead to the conclusion that EnET may be considered a corollary to the classic EMT/MET paradigm.
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Bothwell SW, Janigro D, Patabendige A. Cerebrospinal fluid dynamics and intracranial pressure elevation in neurological diseases. Fluids Barriers CNS 2019; 16:9. [PMID: 30967147 PMCID: PMC6456952 DOI: 10.1186/s12987-019-0129-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 03/19/2019] [Indexed: 01/09/2023] Open
Abstract
The fine balance between the secretion, composition, volume and turnover of cerebrospinal fluid (CSF) is strictly regulated. However, during certain neurological diseases, this balance can be disrupted. A significant disruption to the normal CSF circulation can be life threatening, leading to increased intracranial pressure (ICP), and is implicated in hydrocephalus, idiopathic intracranial hypertension, brain trauma, brain tumours and stroke. Yet, the exact cellular, molecular and physiological mechanisms that contribute to altered hydrodynamic pathways in these diseases are poorly defined or hotly debated. The traditional views and concepts of CSF secretion, flow and drainage have been challenged, also due to recent findings suggesting more complex mechanisms of brain fluid dynamics than previously proposed. This review evaluates and summarises current hypotheses of CSF dynamics and presents evidence for the role of impaired CSF dynamics in elevated ICP, alongside discussion of the proteins that are potentially involved in altered CSF physiology during neurological disease. Undoubtedly CSF secretion, absorption and drainage are important aspects of brain fluid homeostasis in maintaining a stable ICP. Traditionally, pharmacological interventions or CSF drainage have been used to reduce ICP elevation due to over production of CSF. However, these drugs are used only as a temporary solution due to their undesirable side effects. Emerging evidence suggests that pharmacological targeting of aquaporins, transient receptor potential vanilloid type 4 (TRPV4), and the Na+-K+-2Cl- cotransporter (NKCC1) merit further investigation as potential targets in neurological diseases involving impaired brain fluid dynamics and elevated ICP.
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Affiliation(s)
- Steven William Bothwell
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Medical Sciences Building, University Drive, Callaghan, NSW 2308 Australia
| | - Damir Janigro
- FloTBI Inc., Cleveland, OH USA
- Department of Physiology, Case Western Reserve University, Cleveland, OH USA
| | - Adjanie Patabendige
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Medical Sciences Building, University Drive, Callaghan, NSW 2308 Australia
- Hunter Medical Research Institute, Newcastle, NSW Australia
- The Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
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28
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Sepúlveda FV. New light for old enigmas in epithelial transport? Exp Physiol 2019; 104:787-788. [PMID: 30924215 DOI: 10.1113/ep087739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 11/08/2022]
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29
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Larsen EH, Sørensen JN. Stationary and Nonstationary Ion and Water Flux Interactions in Kidney Proximal Tubule: Mathematical Analysis of Isosmotic Transport by a Minimalistic Model. Rev Physiol Biochem Pharmacol 2019; 177:101-147. [DOI: 10.1007/112_2019_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
AbstractOur mathematical model of epithelial transport (Larsen et al. Acta Physiol. 195:171–186, 2009) is extended by equations for currents and conductance of apical SGLT2. With independent variables of the physiological parameter space, the model reproduces intracellular solute concentrations, ion and water fluxes, and electrophysiology of proximal convoluted tubule. The following were shown:Water flux is given by active Na+flux into lateral spaces, while osmolarity of absorbed fluid depends on osmotic permeability of apical membranes.Following aquaporin “knock-out,” water uptake is not reduced but redirected to the paracellular pathway.Reported decrease in epithelial water uptake in aquaporin-1 knock-out mouse is caused by downregulation of active Na+absorption.Luminal glucose stimulates Na+uptake by instantaneous depolarization-induced pump activity (“cross-talk”) and delayed stimulation because of slow rise in intracellular [Na+].Rate of fluid absorption and flux of active K+absorption would have to be attuned at epithelial cell level for the [K+] of the absorbate being in the physiological range of interstitial [K+].Following unilateral osmotic perturbation, time course of water fluxes between intraepithelial compartments provides physical explanation for the transepithelial osmotic permeability being orders of magnitude smaller than cell membranes’ osmotic permeability.Fluid absorption is always hyperosmotic to bath.Deviation from isosmotic absorption is increased in presence of glucose contrasting experimental studies showing isosmotic transport being independent of glucose uptake.For achieving isosmotic transport, the cost of Na+recirculation is predicted to be but a few percent of the energy consumption of Na+/K+pumps.
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30
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Vereshchaga Y, Arnold N, Baumgartner W. Physiological relevance of epithelial geometry: New insights into the standing gradient model and the role of LI cadherin. PLoS One 2018; 13:e0208791. [PMID: 30576326 PMCID: PMC6303100 DOI: 10.1371/journal.pone.0208791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 11/23/2018] [Indexed: 12/14/2022] Open
Abstract
We introduce a mathematical model of an absorbing leaky epithelium to reconsider the problem formulated by Diamond and Bossert in 1967: whether "… some distinctive physiological properties of epithelia might arise as geometrical consequences of epithelial ultrastructure". A standing gradient model of the intercellular cleft (IC) is presented that includes tight junctions (TJ) and ion channels uniformly distributed along the whole cleft. This nonlinear system has an intrinsic homogeneous concentration and the spatial scale necessary to establish it along the cleft. These parameters have not been elucidated so far. We further provide non-perturbative analytical approximations for a broad range of parameters. We found that narrowing of the IC increases ion concentration dramatically and can therefore prevent outflow through tight junctions (TJs) and the lateral membrane, as long as extremely high luminal osmolarities are not reached. Our model predicts that the system is to some extent self-regulating and thereby prevents fluxes into the lumen. Recent experimental evidence has shown that liver-intestine (LI) cadherin can control the up/down flux in intestines via regulation of the cleft width. This finding is in full agreement with predictions of our model. We suggest that LI-cadherin may increase water transport through epithelia via sequential narrowing of the cleft, starting from the highest concentration area at the beginning of the cleft and triggering a propagating squeezing motion.
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Affiliation(s)
- Yana Vereshchaga
- Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Linz, Austria
| | - Nikita Arnold
- Institute of Experimental Physics/Soft Matter Physics, Johannes Kepler University Linz, Linz, Austria
| | - Werner Baumgartner
- Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Linz, Austria
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31
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Expression of Phytoestrogens in pGL2/AQP1 Promoter Reporter System. Chem Res Chin Univ 2018. [DOI: 10.1007/s40242-018-8139-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Dvoriashyna M, Foss AJ, Gaffney EA, Jensen OE, Repetto R. Osmotic and electroosmotic fluid transport across the retinal pigment epithelium: A mathematical model. J Theor Biol 2018; 456:233-248. [DOI: 10.1016/j.jtbi.2018.08.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 08/03/2018] [Accepted: 08/06/2018] [Indexed: 01/26/2023]
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33
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Goralski JL, Wu D, Thelin WR, Boucher RC, Button B. The in vitro effect of nebulised hypertonic saline on human bronchial epithelium. Eur Respir J 2018; 51:13993003.02652-2017. [PMID: 29599187 DOI: 10.1183/13993003.02652-2017] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/28/2018] [Indexed: 11/05/2022]
Abstract
Inhaled hypertonic saline (HS) is an effective therapy for muco-obstructive lung diseases. However, the mechanism of action and principles pertinent to HS administration remain unclear.An in vitro system aerosolised HS to epithelial cells at rates comparable to in vivo conditions. Airway surface liquid (ASL) volume and cell height responses were measured by confocal microscopy under normal and hyperconcentrated mucus states.Aerosolised HS produced a rapid increase in ASL height and decrease in cell height. Added ASL volume was quickly reabsorbed following termination of nebulisation, although cell height did not recover within the same time frame. ASL volume responses to repeated HS administrations were blunted, but could be restored by a hypotonic saline bolus interposed between HS administrations. HS-induced ASL hydration was prolonged with hyperconcentrated mucus on the airway surface, with more modest reductions in cell volume.Aerosolised HS produced osmotically induced increases in ASL height that were limited by active sodium absorption and cell volume-induced reductions in cell water permeability. Mucus on airway surfaces prolonged the effect of HS via mucus-dependent osmotic forces, suggesting that the duration of action of HS is increased in patients with hyperconcentrated mucus.
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Affiliation(s)
- Jennifer L Goralski
- Cystic Fibrosis Research and Treatment Center/Marsico Lung Institute, Chapel Hill, NC, USA.,Division of Pulmonary and Critical Care Medicine, Dept of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Division of Pediatric Pulmonology, Dept of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Dan Wu
- Cystic Fibrosis Research and Treatment Center/Marsico Lung Institute, Chapel Hill, NC, USA
| | | | - Richard C Boucher
- Cystic Fibrosis Research and Treatment Center/Marsico Lung Institute, Chapel Hill, NC, USA.,Division of Pulmonary and Critical Care Medicine, Dept of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Brian Button
- Cystic Fibrosis Research and Treatment Center/Marsico Lung Institute, Chapel Hill, NC, USA.,Dept of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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34
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Sutka M, Amodeo G, Ozu M. Plant and animal aquaporins crosstalk: what can be revealed from distinct perspectives. Biophys Rev 2017; 9:545-562. [PMID: 28871493 DOI: 10.1007/s12551-017-0313-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 08/02/2017] [Indexed: 01/03/2023] Open
Abstract
Aquaporins (AQPs) can be revisited from a distinct and complementary perspective: the outcome from analyzing them from both plant and animal studies. (1) The approach in the study. Diversity found in both kingdoms contrasts with the limited number of crystal structures determined within each group. While the structure of almost half of mammal AQPs was resolved, only a few were resolved in plants. Strikingly, the animal structures resolved are mainly derived from the AQP2-lineage, due to their important roles in water homeostasis regulation in humans. The difference could be attributed to the approach: relevance in animal research is emphasized on pathology and in consequence drug screening that can lead to potential inhibitors, enhancers and/or regulators. By contrast, studies on plants have been mainly focused on the physiological role that AQPs play in growth, development and stress tolerance. (2) The transport capacity. Besides the well-described AQPs with high water transport capacity, large amount of evidence confirms that certain plant AQPs can carry a large list of small solutes. So far, animal AQP list is more restricted. In both kingdoms, there is a great amount of evidence on gas transport, although there is still an unsolved controversy around gas translocation as well as the role of the central pore of the tetramer. (3) More roles than expected. We found it remarkable that the view of AQPs as specific channels has evolved first toward simple transporters to molecules that can experience conformational changes triggered by biochemical and/or mechanical signals, turning them also into signaling components and/or behave as osmosensor molecules.
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Affiliation(s)
- Moira Sutka
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Biodiversidad y Biología Experimental, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Gabriela Amodeo
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Biodiversidad y Biología Experimental, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina.
| | - Marcelo Ozu
- Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Biodiversidad y Biología Experimental, Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina.
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35
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Mechanical Characterization of Microengineered Epithelial Cysts by Using Atomic Force Microscopy. Biophys J 2017; 112:398-409. [PMID: 28122225 DOI: 10.1016/j.bpj.2016.12.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 11/16/2016] [Accepted: 12/19/2016] [Indexed: 01/01/2023] Open
Abstract
Most organs contain interconnected tubular tissues that are one-cell-thick, polarized epithelial monolayers enclosing a fluid-filled lumen. Such tissue organization plays crucial roles in developmental and normal physiology, and the proper functioning of these tissues depends on their regulation by complex biochemical perturbations and equally important, but poorly understood, mechanical perturbations. In this study, by combining micropatterning techniques and atomic force microscopy, we developed a simple in vitro experimental platform for characterizing the mechanical properties of the MDCK II cyst, the simplest model of lumen-enclosing epithelial monolayers. By using this platform, we estimated the elasticity of the cyst monolayer and showed that the presence of a luminal space influences cyst mechanics substantially, which could be attributed to polarization and tissue-level coordination. More interestingly, the results from force-relaxation experiments showed that the cysts also displayed tissue-level poroelastic characteristics that differed slightly from those of single cells. Our study provides the first quantitative findings, to our knowledge, on the tissue-level mechanics of well-polarized epithelial cysts and offers new insights into the interplay between cyst mechanics and cyst physiology. Moreover, our simple platform is a potentially useful tool for enhancing the current understanding of cyst mechanics in health and disease.
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36
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Fischbarg J, Hernandez JA, Rubashkin AA, Iserovich P, Cacace VI, Kusnier CF. Epithelial Fluid Transport is Due to Electro-osmosis (80%), Plus Osmosis (20%). J Membr Biol 2017. [PMID: 28623474 PMCID: PMC5489618 DOI: 10.1007/s00232-017-9966-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Epithelial fluid transport, an important physiological process shrouded in a long-standing enigma, may finally be moving closer to a solution. We propose that, for the corneal endothelium, relative proportions for the driving forces for fluid transport are 80% of paracellular electro-osmosis, and 20% classical transcellular osmosis. These operate in a cyclical process with a period of 9.2 s, which is dictated by the decrease and exhaustion of cellular Na+. Paracellular electro-osmosis is sketched here, and partially discussed as much as the subject still allows; transcellular osmosis is presented at length.
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Affiliation(s)
- Jorge Fischbarg
- Ininca, Conicet, Univ. of Buenos Aires2, Buenos Aires, Argentina.
| | - Julio A Hernandez
- Biophysics Section, Science Faculty, Univ. of the Republic, Montevideo, Uruguay
| | - Andrey A Rubashkin
- Institute of Cytology of the Russian Academy of Science, St. Petersburg, Russia
| | | | | | - Carlos F Kusnier
- Ininca, Conicet, Univ. of Buenos Aires2, Buenos Aires, Argentina
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ILDR1 is important for paracellular water transport and urine concentration mechanism. Proc Natl Acad Sci U S A 2017; 114:5271-5276. [PMID: 28461473 DOI: 10.1073/pnas.1701006114] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Whether the tight junction is permeable to water remains highly controversial. Here, we provide evidence that the tricellular tight junction is important for paracellular water permeation and that Ig-like domain containing receptor 1 (ILDR1) regulates its permeability. In the mouse kidney, ILDR1 is localized to tricellular tight junctions of the distal tubules. Genetic knockout of Ildr1 in the mouse kidney causes polyuria and polydipsia due to renal concentrating defects. Microperfusion of live renal distal tubules reveals that they are impermeable to water in normal animals but become highly permeable to water in Ildr1 knockout animals whereas paracellular ionic permeabilities in the Ildr1 knockout mouse renal tubules are not affected. Vasopressin cannot correct paracellular water loss in Ildr1 knockout animals despite normal effects on the transcellular aquaporin-2-dependent pathway. In cultured renal epithelial cells normally lacking the expression of Ildr1, overexpression of Ildr1 significantly reduces the paracellular water permeability. Together, our study provides a mechanism of how cells transport water and shows how such a mechanism may be exploited as a therapeutic approach to maintain water homeostasis.
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38
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Runggaldier D, Pradas LG, Neckel PH, Mack AF, Hirt B, Gleiser C. Claudin expression in the rat endolymphatic duct and sac - first insights into regulation of the paracellular barrier by vasopressin. Sci Rep 2017; 7:45482. [PMID: 28374851 PMCID: PMC5379655 DOI: 10.1038/srep45482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/28/2017] [Indexed: 12/13/2022] Open
Abstract
Hearing and balance functions of the inner ear rely on the homeostasis of the endolymphatic fluid. When disturbed, pathologic endolymphatic hydrops evolves as observed in Menière’s disease. The molecular basis of inner ear fluid regulation across the endolymphatic epithelium is largely unknown. In this study we identified the specific expression of the tight junction (TJ) molecules Claudin 3, 4, 6, 7, 8, 10, and 16 in epithelial preparations of the rat inner ear endolymphatic duct (ED) and endolymphatic sac (ES) by high-throughput qPCR and immunofluorescence confocal microscopy. Further we showed that Claudin 4 in the ES is a target of arginine-vasopressin (AVP), a hormone elevated in Menière’s disease. Moreover, our transmission-electron microscopy (TEM) analysis revealed that the TJs of the ED were shallow and shorter compared to the TJ of the ES indicating facilitation of a paracellular fluid transport across the ED epithelium. The significant differences in the subcellular localization of the barrier-forming protein Claudin 3 between the ED and ES epithelium further support the TEM observations. Our results indicate a high relevance of Claudin 3 and Claudin 4 as important paracellular barrier molecules in the ED and ES epithelium with potential involvement in the pathophysiology of Menière’s disease.
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Affiliation(s)
- Daniel Runggaldier
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Lidia Garcia Pradas
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Peter H Neckel
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Andreas F Mack
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Bernhard Hirt
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
| | - Corinna Gleiser
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Tübingen, Germany
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Laxative Effects of Total Diterpenoids Extracted from the Roots of Euphorbia pekinensis Are Attributable to Alterations of Aquaporins in the Colon. Molecules 2017; 22:molecules22030465. [PMID: 28335427 PMCID: PMC6155307 DOI: 10.3390/molecules22030465] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/08/2017] [Accepted: 03/12/2017] [Indexed: 12/21/2022] Open
Abstract
This study was designed to evaluate the toxic effects of total diterpenoids extracted from the roots of Euphorbia pekinensis (TDEP) on the mouse colon and to clarify the mechanism. Dried powdered roots of E. pekinensis were extracted with chloroform, and then the extract (6.7 g) was subjected to column chromatography and preparative TLC, giving TDEP. Using the HPLC-DAD method, the purity of TDEP was determined as 85.26%. Mice were orally administered with TDEP (3.942, 19.71 and 39.42 mg/kg), after which fecal water content and colon water content were examined. Both of them increased over time after TDEP administration, accompanied by severe diarrhea. Three hours after TDEP administration, the animals were sacrificed to obtain their colons. The mRNA and protein expression levels of aquaporin 1 (AQP1), AQP3 and AQP4 in the colon were measured using real-time RT-PCR and Western blotting, respectively. TDEP significantly increased the levels of AQP3 and AQP4, but decreased that of AQP1 in dose-dependent manners. Similarly, Pekinenin C, a casbane diterpenoid, significantly increased AQP3 protein and mRNA expressions in human intestinal epithelial cells (HT-29). Histopathological examination revealed that the colon was not significantly damaged. The laxative effects of E. pekinensis were associated with the alterations of AQPs in the colon by TDEP.
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Saint-Criq V, Gray MA. Role of CFTR in epithelial physiology. Cell Mol Life Sci 2016; 74:93-115. [PMID: 27714410 PMCID: PMC5209439 DOI: 10.1007/s00018-016-2391-y] [Citation(s) in RCA: 241] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 12/20/2022]
Abstract
Salt and fluid absorption and secretion are two processes that are fundamental to epithelial function and whole body fluid homeostasis, and as such are tightly regulated in epithelial tissues. The CFTR anion channel plays a major role in regulating both secretion and absorption in a diverse range of epithelial tissues, including the airways, the GI and reproductive tracts, sweat and salivary glands. It is not surprising then that defects in CFTR function are linked to disease, including life-threatening secretory diarrhoeas, such as cholera, as well as the inherited disease, cystic fibrosis (CF), one of the most common life-limiting genetic diseases in Caucasian populations. More recently, CFTR dysfunction has also been implicated in the pathogenesis of acute pancreatitis, chronic obstructive pulmonary disease (COPD), and the hyper-responsiveness in asthma, underscoring its fundamental role in whole body health and disease. CFTR regulates many mechanisms in epithelial physiology, such as maintaining epithelial surface hydration and regulating luminal pH. Indeed, recent studies have identified luminal pH as an important arbiter of epithelial barrier function and innate defence, particularly in the airways and GI tract. In this chapter, we will illustrate the different operational roles of CFTR in epithelial function by describing its characteristics in three different tissues: the airways, the pancreas, and the sweat gland.
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Affiliation(s)
- Vinciane Saint-Criq
- Epithelial Research Group, Institute for Cell and Molecular Biosciences, University Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH UK
| | - Michael A. Gray
- Epithelial Research Group, Institute for Cell and Molecular Biosciences, University Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH UK
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41
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The Epithelial Sodium Channel and the Processes of Wound Healing. BIOMED RESEARCH INTERNATIONAL 2016; 2016:5675047. [PMID: 27493961 PMCID: PMC4963570 DOI: 10.1155/2016/5675047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 06/15/2016] [Indexed: 12/19/2022]
Abstract
The epithelial sodium channel (ENaC) mediates passive sodium transport across the apical membranes of sodium absorbing epithelia, like the distal nephron, the intestine, and the lung airways. Additionally, the channel has been involved in the transduction of mechanical stimuli, such as hydrostatic pressure, membrane stretch, and shear stress from fluid flow. Thus, in vascular endothelium, it participates in the control of the vascular tone via its activity both as a sodium channel and as a shear stress transducer. Rather recently, ENaC has been shown to participate in the processes of wound healing, a role that may also involve its activities as sodium transporter and as mechanotransducer. Its presence as the sole channel mediating sodium transport in many tissues and the diversity of its functions probably underlie the complexity of its regulation. This brief review describes some aspects of ENaC regulation, comments on evidence about ENaC participation in wound healing, and suggests possible regulatory mechanisms involved in this participation.
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Hanukoglu I, Hanukoglu A. Epithelial sodium channel (ENaC) family: Phylogeny, structure-function, tissue distribution, and associated inherited diseases. Gene 2016; 579:95-132. [PMID: 26772908 PMCID: PMC4756657 DOI: 10.1016/j.gene.2015.12.061] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 12/20/2015] [Accepted: 12/22/2015] [Indexed: 01/24/2023]
Abstract
The epithelial sodium channel (ENaC) is composed of three homologous subunits and allows the flow of Na(+) ions across high resistance epithelia, maintaining body salt and water homeostasis. ENaC dependent reabsorption of Na(+) in the kidney tubules regulates extracellular fluid (ECF) volume and blood pressure by modulating osmolarity. In multi-ciliated cells, ENaC is located in cilia and plays an essential role in the regulation of epithelial surface liquid volume necessary for cilial transport of mucus and gametes in the respiratory and reproductive tracts respectively. The subunits that form ENaC (named as alpha, beta, gamma and delta, encoded by genes SCNN1A, SCNN1B, SCNN1G, and SCNN1D) are members of the ENaC/Degenerin superfamily. The earliest appearance of ENaC orthologs is in the genomes of the most ancient vertebrate taxon, Cyclostomata (jawless vertebrates) including lampreys, followed by earliest representatives of Gnathostomata (jawed vertebrates) including cartilaginous sharks. Among Euteleostomi (bony vertebrates), Actinopterygii (ray finned-fishes) branch has lost ENaC genes. Yet, most animals in the Sarcopterygii (lobe-finned fish) branch including Tetrapoda, amphibians and amniotes (lizards, crocodiles, birds, and mammals), have four ENaC paralogs. We compared the sequences of ENaC orthologs from 20 species and established criteria for the identification of ENaC orthologs and paralogs, and their distinction from other members of the ENaC/Degenerin superfamily, especially ASIC family. Differences between ENaCs and ASICs are summarized in view of their physiological functions and tissue distributions. Structural motifs that are conserved throughout vertebrate ENaCs are highlighted. We also present a comparative overview of the genotype-phenotype relationships in inherited diseases associated with ENaC mutations, including multisystem pseudohypoaldosteronism (PHA1B), Liddle syndrome, cystic fibrosis-like disease and essential hypertension.
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Affiliation(s)
- Israel Hanukoglu
- Laboratory of Cell Biology, Faculty of Natural Sciences, Ariel University, Ariel, Israel.
| | - Aaron Hanukoglu
- Division of Pediatric Endocrinology, E. Wolfson Medical Center, Holon, Israel; Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel
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Net Fluorescein Flux Across Corneal Endothelium Strongly Suggests Fluid Transport is due to Electro-osmosis. J Membr Biol 2016; 249:469-73. [PMID: 26989056 PMCID: PMC4942490 DOI: 10.1007/s00232-016-9887-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/09/2016] [Indexed: 11/04/2022]
Abstract
We have presented prior evidence suggesting that fluid transport results from electro-osmosis at the intercellular junctions of the corneal endothelium. Such phenomenon ought to drag other extracellular solutes. We have investigated this using fluorescein-Na2 as an extracellular marker. We measured unidirectional fluxes across layers of cultured human corneal endothelial (HCE) cells. SV-40-transformed HCE layers were grown to confluence on permeable membrane inserts. The medium was DMEM with high glucose and no phenol red. Fluorescein-labeled medium was placed either on the basolateral or the apical side of the inserts; the other side carried unlabeled medium. The inserts were held in a CO2 incubator for 1 h (at 37 °C), after which the entire volume of the unlabeled side was collected. After that, label was placed on the opposite side, and the corresponding paired sample was collected after another hour. Fluorescein counts were determined with a (Photon Technology) DeltaScan fluorometer (excitation 380 nm; emission 550 nm; 2 nm bwth). Samples were read for 60 s. The cells utilized are known to transport fluid from the basolateral to the apical side, just as they do in vivo in several species. We used 4 inserts for influx and efflux (total: 20 1-h periods). We found a net flux of fluorescein from the basolateral to the apical side. The flux ratio was 1.104 ± 0.056. That difference was statistically significant (p = 0.00006, t test, paired samples). The endothelium has a definite restriction at the junctions. Hence, an asymmetry in unidirectional fluxes cannot arise from osmosis, and can only point instead to paracellular solvent drag. We suggest, once more, that such drag is due to electro-osmotic coupling at the paracellular junctions.
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Püspöki Z, Uhlmann V, Vonesch C, Unser M. Design of Steerable Wavelets to Detect Multifold Junctions. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2016; 25:643-657. [PMID: 26685237 DOI: 10.1109/tip.2015.2507981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We propose a framework for the detection of junctions in images. Although the detection of edges and key points is a well examined and described area, the multiscale detection of junction centers, especially for odd orders, poses a challenge in pattern analysis. The goal of this paper is to build optimal junction detectors based on 2D steerable wavelets that are polar-separable in the Fourier domain. The approaches we develop are general and can be used for the detection of arbitrary symmetric and asymmetric junctions. The backbone of our construction is a multiscale pyramid with a radial wavelet function where the directional components are represented by circular harmonics and encoded in a shaping matrix. We are able to detect M -fold junctions in different scales and orientations. We provide experimental results on both simulated and real data to demonstrate the effectiveness of the algorithm.
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Cacace V, Kusnier CF, Fischbarg J. RETRACTED ARTICLE: Net Fluorescein Flux Across Corneal Endothelium Suggests Fluid Transport is Driven by Electroosmosis. J Membr Biol 2015; 249:197. [PMID: 26423751 PMCID: PMC4851691 DOI: 10.1007/s00232-015-9849-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 09/18/2015] [Indexed: 11/30/2022]
Affiliation(s)
- V Cacace
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina
| | - C F Kusnier
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina
| | - J Fischbarg
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina.
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Madsen SS, Engelund MB, Cutler CP. Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes. THE BIOLOGICAL BULLETIN 2015; 229:70-92. [PMID: 26338871 DOI: 10.1086/bblv229n1p70] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these animals are in intimate contact with the surrounding milieu, passive water loss and uptake represent two of the major osmoregulatory challenges that need compensation. However, neither obligatory nor regulatory water transport nor their mechanisms have been elucidated to the same degree as, for example, ion transport in fishes. Currently fewer than 60 papers address fish aquaporins. Most of these papers identify "what is present" and describe tissue expression patterns in various teleosts. The agnathans, chondrichthyans, and functionality of fish aquaporins generally have received little attention. This review emphasizes the functional physiology of aquaporins in fishes, focusing on transepithelial water transport in osmoregulatory organs in euryhaline species - primarily teleosts, but covering other taxonomic groups as well. Most current knowledge comes from teleosts, and there is a strong need for related information on older fish clades. Our survey aims to stimulate new, original research in this area and to bring together new collaborations across disciplines.
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Affiliation(s)
- Steffen S Madsen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark;
| | - Morten B Engelund
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Christopher P Cutler
- Department of Biology, Georgia Southern University, P.O. Box 8042, Statesboro, Georgia 30460
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Teichmann J, Nitschke M, Pette D, Valtink M, Gramm S, Härtel FV, Noll T, Funk RHW, Engelmann K, Werner C. Thermo-responsive cell culture carriers based on poly(vinyl methyl ether)-the effect of biomolecular ligands to balance cell adhesion and stimulated detachment. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2015; 16:045003. [PMID: 27877823 PMCID: PMC5090182 DOI: 10.1088/1468-6996/16/4/045003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/19/2015] [Accepted: 06/22/2015] [Indexed: 06/06/2023]
Abstract
Two established material systems for thermally stimulated detachment of adherent cells were combined in a cross-linked polymer blend to merge favorable properties. Through this approach poly(N-isopropylacrylamide) (PNiPAAm) with its superior switching characteristic was paired with a poly(vinyl methyl ether)-based composition that allows adjusting physico-chemical and biomolecular properties in a wide range. Beyond pure PNiPAAm, the proposed thermo-responsive coating provides thickness, stiffness and swelling behavior, as well as an apposite density of reactive sites for biomolecular functionalization, as effective tuning parameters to meet specific requirements of a particular cell type regarding initial adhesion and ease of detachment. To illustrate the strength of this approach, the novel cell culture carrier was applied to generate transplantable sheets of human corneal endothelial cells (HCEC). Sheets were grown, detached, and transferred onto planar targets. Cell morphology, viability and functionality were analyzed by immunocytochemistry and determination of transepithelial electrical resistance (TEER) before and after sheet detachment and transfer. HCEC layers showed regular morphology with appropriate TEER. Cells were positive for function-associated marker proteins ZO-1, Na+/K+-ATPase, and paxillin, and extracellular matrix proteins fibronectin, laminin and collagen type IV before and after transfer. Sheet detachment and transfer did not impair cell viability. Subsequently, a potential application in ophthalmology was demonstrated by transplantation onto de-endothelialized porcine corneas in vitro. The novel thermo-responsive cell culture carrier facilitates the generation and transfer of functional HCEC sheets. This paves the way to generate tissue engineered human corneal endothelium as an alternative transplant source for endothelial keratoplasty.
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Affiliation(s)
- Juliane Teichmann
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Dagmar Pette
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
| | - Monika Valtink
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Stefan Gramm
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
- Herlac Coswig GmbH, Industriestraße 28, D-01640 Coswig, Germany
| | - Frauke V Härtel
- Institute of Physiology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Thomas Noll
- Institute of Physiology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
| | - Richard H W Funk
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
| | - Katrin Engelmann
- Institute of Anatomy, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, D-01307 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Flemmingstraße 2, D-09116 Chemnitz, Germany
| | - Carsten Werner
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Straße 6, D-01069 Dresden, Germany
- CRTD/DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Fetscherstraße 105, D-01307 Dresden, Germany
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Maisel K, Chattopadhyay S, Moench T, Hendrix C, Cone R, Ensign LM, Hanes J. Enema ion compositions for enhancing colorectal drug delivery. J Control Release 2015; 209:280-7. [PMID: 25937321 PMCID: PMC4458383 DOI: 10.1016/j.jconrel.2015.04.040] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/12/2015] [Accepted: 04/29/2015] [Indexed: 10/23/2022]
Abstract
Delivering drugs to the colorectum by enema has advantages for treating or preventing both local and systemic diseases. However, the properties of the enema itself are not typically exploited for improving drug delivery. Sodium ions are actively pumped out of the lumen of the colon, which is followed by osmotically-driven water absorption, so we hypothesized that this natural mechanism could be exploited to drive nanoparticles and drugs to the colorectal tissue surface. Here, we report that sodium-based, absorption-inducing (hypotonic) enemas rapidly transport hydrophilic drugs and non-mucoadhesive, mucus penetrating nanoparticles (MPP), deep into the colorectal folds to reach virtually the entire colorectal epithelial surface. In contrast, isotonic and secretion-inducing (hypertonic) vehicles led to non-uniform, poor surface coverage. Sodium-based enemas induced rapid fluid absorption even when moderately hyper-osmolal (~350 mOsm) compared to blood (~300 mOsm), which suggests that active sodium absorption plays a key role in osmosis-driven fluid uptake. We then used tenofovir, an antiretroviral drug in clinical trials for preventing HIV, to test the effects of enema composition on local and systemic drug delivery. We found that strongly hypotonic and hypertonic enemas caused rapid systemic drug uptake, whereas moderately hypotonic enemas with ion compositions similar to feces resulted in high local tissue levels with minimal systemic drug exposure. Similarly, moderately hypotonic enemas provided improved local drug retention in colorectal tissue, whereas hypertonic and isotonic enemas provided markedly reduced drug retention in colorectal tissue. Lastly, we found that moderately hypotonic enema formulations caused little to no detectable epithelial damage, while hypertonic solutions caused significant damage, including epithelial sloughing; the epithelial damage caused increased systemic drug absorption and penetration of MPP into colorectal tissue, a potential advantage in certain drug delivery applications. In summary, we illustrate that enema composition can be adjusted to maximize local versus systemic drug delivery, and that mildly hypotonic, sodium-based vehicles can provide uniform drug and MPP delivery in the colon that maximizes local drug concentrations.
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Affiliation(s)
- Katharina Maisel
- Center for Nanomedicine, Johns Hopkins University School of Medicine, 400N. Broadway, Baltimore, MD 21231 USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Baltimore, MD 21205 USA
| | - Sumon Chattopadhyay
- Center for Nanomedicine, Johns Hopkins University School of Medicine, 400N. Broadway, Baltimore, MD 21231 USA; Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 USA
| | - Thomas Moench
- Department of Biophysics, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 USA; ReProtect, Inc, 703 Stags Head Road, Baltimore, MD 21286 USA
| | - Craig Hendrix
- Department of Clinical Pharmacology, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD 21287, USA
| | - Richard Cone
- Center for Nanomedicine, Johns Hopkins University School of Medicine, 400N. Broadway, Baltimore, MD 21231 USA; Department of Biophysics, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 USA
| | - Laura M Ensign
- Center for Nanomedicine, Johns Hopkins University School of Medicine, 400N. Broadway, Baltimore, MD 21231 USA; Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 USA; Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD 21231, USA; Center for Cancer Nanotechnology Excellence, the Institute for NanoBioTechnology, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA.
| | - Justin Hanes
- Center for Nanomedicine, Johns Hopkins University School of Medicine, 400N. Broadway, Baltimore, MD 21231 USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Baltimore, MD 21205 USA; Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 USA; Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD 21231, USA; Center for Cancer Nanotechnology Excellence, the Institute for NanoBioTechnology, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA; Departments of Neurosurgery, Oncology, and Pharmacology & Molecular Sciences, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD 21287, USA.
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Sharp K, Crampin E, Sneyd J. A spatial model of fluid recycling in the airways of the lung. J Theor Biol 2015; 382:198-215. [PMID: 26169010 DOI: 10.1016/j.jtbi.2015.06.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 06/26/2015] [Accepted: 06/30/2015] [Indexed: 12/11/2022]
Abstract
The genetic disease cystic fibrosis (CF) is a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, and results in viscous mucus and impaired mucociliary clearance leading to chronic recurring pulmonary infections. Although extensive experimental research has been conducted over the last few decades, CF lung pathophysiology remains controversial. There are two competing explanations for the observed depletion of periciliary liquid (PCL) in CF lungs. The low volume hypothesis assumes fluid hyperabsorption through surface epithelia due to an over-active epithelial Na(+) channel (ENaC), and the low secretion hypothesis assumes inspissated mucins secreted from glands due to lack of serous fluid secreted from gland acini. We present a spatial mathematical model that reflects in vivo fluid recycling via submucosal gland (SMG) secretion, and absorption through surface epithelia. We then test the model in CF conditions by increasing ENaC open probability and decreasing SMG flux while simultaneously reducing CFTR open probability. Increasing ENaC activity only results in increased fluid absorption across surface epithelia, as seen in in vitro experiments. However, combining potential CF mechanisms results in markedly less fluid absorbed while providing the largest reduction in PCL volume, suggesting that a compromise in gland fluid secretion dominates over increased ENaC activity to decrease the amount of fluid transported transcellularly in CF lungs in vivo. Model results also indicate that a spatial model is necessary for an accurate calculation of total fluid transport, as the effects of spatial gradients can be severe, particularly in close proximity to the SMGs.
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Affiliation(s)
- Katie Sharp
- Department of Mathematics, University of Auckland, 23 Princes St, Auckland CBD, Auckland 1010, New Zealand.
| | - Edmund Crampin
- Department of Biomedical Engineering, Level 4, University of Melbourne, Parkville 3010, Victoria, Australia
| | - James Sneyd
- Department of Mathematics, University of Auckland, 23 Princes St, Auckland CBD, Auckland 1010, New Zealand
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50
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Pan CS, Liu YH, Liu YY, Zhang Y, He K, Yang XY, Hu BH, Chang X, Wang MX, Wei XH, Fan JY, Wu XM, Han JY. Salvianolic Acid B Ameliorates Lipopolysaccharide-Induced Albumin Leakage from Rat Mesenteric Venules through Src-Regulated Transcelluar Pathway and Paracellular Pathway. PLoS One 2015; 10:e0126640. [PMID: 25992563 PMCID: PMC4438061 DOI: 10.1371/journal.pone.0126640] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 04/05/2015] [Indexed: 12/15/2022] Open
Abstract
Lipopolysaccharide (LPS) causes microvascular barrier disruption, leading to albumin leakage from microvessels resulting in a range of disastrous sequels. Salvianolic acid B (SalB) is a major water-soluble component derived from Salvia miltiorrhiza. Previous studies showed its potential to attenuate microvascular barrier dysfunction, but the underlying mechanism is not fully understood. The present study was intended to investigate the impact of SalB on endothelial cell barrier in vivo in rat mesenteric venules as well as in vitro in human umbilical vein endothelial cells (HUVECs), aiming at disclosing the mechanism thereof, particularly the role of Src in its action. Male Wistar rats were challenged by infusion of LPS (2 mg/kg/h) through left femoral vein for 90 min. SalB (5 mg/kg/h) was administrated either simultaneously with LPS or 30 min after LPS infusion through the left jugular vein. Vesicles in venular walls were observed by electron microscopy. HUVECs were incubated with LPS with or without SalB. The expression of Zonula occluden-1 (ZO-1), VE-cadherin, caveolin-1 and Src in HUVECs was assessed by Western blot and confocal microscopy, binding of SalB to Src was measured using Surface Plasmon Resonance and BioLayer Interferometry. Treatment with SalB inhibited albumin leakage from rat mesenteric venules and inhibited the increase of vesicle number in venular endothelial cells induced by LPS. In addition, SalB inhibited the degradation of ZO-1, the phosphorylation and redistribution of VE-cadherin, the expression and phosphorylation of caveolin-1, and phosphoirylation of Src in HUVECs exposed to LPS. Furthermore, SalB was found able to bind to Src. This study demonstrates that protection of SalB against microvascular barrier disruption is a process involving both para- and trans-endothelial cell pathway, and highly suggests Src as the key enzyme for SalB to work.
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Affiliation(s)
- Chun-Shui Pan
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Ying-Hua Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital& Institute, Beijing, China
| | - Yu-Ying Liu
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Yu Zhang
- Department of Integration of Traditional Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Ke He
- Department of Integration of Traditional Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Xiao-Yuan Yang
- Department of Integration of Traditional Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Bai-He Hu
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Xin Chang
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Ming-Xia Wang
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Xiao-Hong Wei
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
| | - Jing-Yu Fan
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
| | - Xin-Min Wu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital& Institute, Beijing, China
| | - Jing-Yan Han
- Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China
- Department of Integration of Traditional Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, China
- Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- Key Laboratory of Stasis and Phlegm, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
- * E-mail:
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