How Epithelial Cells Reorient in Response to Cyclic Stretching

Mapping Intimacies ◽

10.21203/rs.3.rs-347408/v1 ◽

2021 ◽

Author(s):

Jui-Chien Lien ◽

Yu-Li Wang

Keyword(s):

Epithelial Cells ◽

Myosin Ii ◽

Underlying Mechanism ◽

Adherent Cells ◽

Static Stretching ◽

Relaxation Phase ◽

Cyclic Stretching ◽

The Difference ◽

Cell Reorientation

Abstract Many types of adherent cells are known to reorient upon uniaxial cyclic stretching perpendicularly to the direction of stretching to facilitate such important events as wound healing, angiogenesis, and morphogenesis. While this phenomenon has been documented for decades, the underlying mechanism remains poorly understood. Using an on-stage stretching device that allowed programmable stretching with synchronized imaging, we found that the reorientation of NRK epithelial cells took place primarily during the relaxation phase when cells underwent rapid global retraction followed by extension transverse to the direction of stretching. Inhibition of myosin II caused cells to orient along the direction of stretching, whereas disassembly of microtubules enhanced transverse reorientation. Our results indicate distinct roles of stretching and relaxation in cell reorientation and implicate a role of myosin II-dependent contraction via a microtubule-modulated mechanism. The importance of relaxation phase also explains the difference between the responses to cyclic and static stretching.

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Cyclic stretching-induced epithelial cell reorientation is driven by microtubule-modulated transverse extension during the relaxation phase

Scientific Reports ◽

10.1038/s41598-021-93987-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jui-Chien Lien ◽

Yu-li Wang

Keyword(s):

Wound Healing ◽

Myosin Ii ◽

Underlying Mechanism ◽

Adherent Cells ◽

Static Stretching ◽

Relaxation Phase ◽

Cyclic Stretching ◽

The Difference ◽

Cell Reorientation

AbstractMany types of adherent cells are known to reorient upon uniaxial cyclic stretching perpendicularly to the direction of stretching to facilitate such important events as wound healing, angiogenesis, and morphogenesis. While this phenomenon has been documented for decades, the underlying mechanism remains poorly understood. Using an on-stage stretching device that allowed programmable stretching with synchronized imaging, we found that the reorientation of NRK epithelial cells took place primarily during the relaxation phase when cells underwent rapid global retraction followed by extension transverse to the direction of stretching. Inhibition of myosin II caused cells to orient along the direction of stretching, whereas disassembly of microtubules enhanced transverse reorientation. Our results indicate distinct roles of stretching and relaxation in cell reorientation and implicate a role of myosin II-dependent contraction via a microtubule-modulated mechanism. The importance of relaxation phase also explains the difference between the responses to cyclic and static stretching.

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Rspo3 regulates the abnormal differentiation of small intestinal epithelial cells in diabetic state

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02385-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ti-Dong Shan ◽

Han Yue ◽

Xue-Guo Sun ◽

Yue-Ping Jiang ◽

Li Chen

Keyword(s):

Epithelial Cells ◽

Bioinformatics Analysis ◽

Intestinal Epithelial Cells ◽

Underlying Mechanism ◽

Luciferase Reporter ◽

Intestinal Epithelial ◽

Epithelial Stem Cells ◽

Diabetic State ◽

Definitive Evidence

Abstract Background The complications caused by diabetes mellitus (DM) are the focus of clinical treatment. However, little is known about diabetic enteropathy (DE) and its potential underlying mechanism. Methods Intestinal epithelial cells (IECs) and intestinal epithelial stem cells (IESCs) were harvested from BKS.Cg-Dock7m+/+Leprdb/JNju (DM) mice, and the expression of R-Spondin 3 (Rspo3) was detected by RT-qPCR, Western blotting, immunohistochemistry, and immunofluorescence. The role of Rspo3 in the abnormal differentiation of IECs during DM was confirmed by knockdown experiments. Through miRNA expression profiling, bioinformatics analysis, and RT-qPCR, we further analyzed the differentiation-related miRNAs in the IECs from mice with DM. Results Abnormal differentiation of IECs was observed in the mice with DM. The expression of Rspo3 was upregulated in the IECs from the mice with DM. This phenomenon was associated with Rspo3 overexpression. Additionally, Rspo3 is a major determinant of Lgr5+ stem cell identity in the diabetic state. Microarray analysis, bioinformatics analysis, and luciferase reporter assays revealed that microRNA (miR)-380-5p directly targeted Rspo3. Moreover, miR-380-5p upregulation was observed to attenuate the abnormal differentiation of IECs by regulating Rspo3 expression. Conclusions Together, our results provide definitive evidence of the essential role of Rspo3 in the differentiation of IECs in DM.

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G6PD Deficiency Prevalence as a Cause of Neonatal Jaundice in a Neonatal Ward in Dohuk, Iraq

American Journal of Perinatology ◽

10.1055/s-0039-1700854 ◽

2019 ◽

Author(s):

Adil Abozaid Eissa ◽

Bijar Ali Haji ◽

Adnan Anwar Al-Doski

Keyword(s):

G6pd Deficiency ◽

Complete Blood Count ◽

Underlying Mechanism ◽

Total Serum ◽

Current Case ◽

Indirect Bilirubin ◽

Significant Difference ◽

The Difference ◽

Glucose 6 Phosphate Dehydrogenase

Abstract Objective The current study initiated to address the effect of glucose-6-phosphate dehydrogenase (G6PD) deficiency on the pathogenesis and the severity of neonatal hyperbilirubinemia (NHB). Study Design A total of 100 newborns with moderate to severe indirect hyperbilirubinemia and 50 normal neonates without hyperbilirubinemia had been enrolled in the current case–control study. All enrolled neonates had been tested for ABO and Rh(D) blood grouping, Total serum bilirubin measurement, complete blood count, morphology, reticulocyte counts, direct Coombs' test, and G6PD enzyme assay. Results From all enrolled hyperbilirubinemic neonates, 16% were G6PD deficient and this displays a statistically significant difference in comparison to controls (only 6% were G6PD deficient). Also, significant difference was found in the level of serum indirect bilirubin among G6PD-deficient neonate in comparison to G6PD nondeficient neonates which had contributed significantly to the difference in the duration of phototherapy and hospitalization among deficient neonate. Despite this, no significant difference found in the onset of presentation, reticulocytes count, and age of neonates between the two groups (G6PD-deficient and G6PD nondeficient neonates). Conclusion The current study augments the etiological role of G6PD in the causation and severity of NHB in the region; however, in the absence of significant difference in the reticulocytes and the hemoglobin level, the underlying mechanism cannot be backed to the excess hemolysis alone.

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Rspo3 regulates abnormal differentiation of small intestinal epithelial cells in diabetic state

10.21203/rs.3.rs-265005/v1 ◽

2021 ◽

Author(s):

Ti-Dong Shan ◽

Yue Han ◽

Xue-Guo Sun ◽

Yue-Ping Jiang ◽

Li Chen

Keyword(s):

Epithelial Cells ◽

Intestinal Epithelial Cells ◽

Expression Profiles ◽

Underlying Mechanism ◽

Bioinformatic Analysis ◽

Luciferase Reporter ◽

Intestinal Epithelial ◽

Definitive Evidence ◽

Small Intestinal

Abstract Objective: The problems caused by diabetes mellitus (DM) related complications are the focus in clinical treatment. However, little is known about diabetic enteropathy (DE) and its the potential underlying mechanism. Methods: Intestinal cells (IEC) and Intestinal stem cells (IESC) obtained from BKS.Cg-Dock7m+/+Leprdb/JNju (DM) mice were used to detect Rspo3 by RT-qPCR, western blotting, Immunohistochemistry, and immunofluorescence. The role of Rspo3 in the abnormal differentiation of IECs of DM was clarified by knockout experiments. Through miRNA expression profiles, bioinformatic analysis, and RT-qPCR, we further analyzed differentiation related miRNA from IECs in DM mice. Results: The abnormal differentiation of small intestinal epithelial cells (IECs) was found in DM state. The expression of R-spondin 3 (Rspo3) was upregulated in IECs of DM state. And this phenomenon was associated with R-spondin 3 (Rspo3) overexpression. Additionally, Rspo3 is a major determinant of Lgr5+ stem cell identity upon DM state. Microarray analysis, Bioinformatics analysis and luciferase reporter assays revealed that microRNA (miR)-380-5p was directly targeted Rspo3. Moreover, miR-380-5p upregulation was observed to attenuate the abnormal differentiation of IECs through Rspo3 expression. Conclusion: Together, our results provide definitive evidence for the essential role of Rspo3 in differentiation of small intestinal epithelial cells (IECs) in DM state.

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Suppressing Syndecan-1 Shedding Ameliorates Intestinal Epithelial Inflammation through Inhibiting NF-κB Pathway and TNF-α

Gastroenterology Research and Practice ◽

10.1155/2016/6421351 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Yan Zhang ◽

Zhongqiu Wang ◽

Jun Liu ◽

Zhenyu Zhang ◽

Ye Chen

Keyword(s):

Epithelial Cells ◽

Intestinal Inflammation ◽

Inflammatory Responses ◽

Intestinal Epithelial Cells ◽

Underlying Mechanism ◽

Intestinal Epithelial ◽

Cell Models ◽

Tnf Α ◽

Epithelial Inflammation

Syndecan-1 (SDC1), with a long variable ectodomain carrying heparan sulfate chains, participates in many steps of inflammatory responses. But reports about the efforts of SDC1’s unshedding ectodomain on intestinal epithelial inflammation and the precise underlying mechanism are limited. In our study, unshedding SDC1 from intestinal epithelial cell models was established by transfecting with unshedding SDC1 plasmid into the cell, respectively. And the role of unshedding SDC1 in intestinal inflammation was further investigated. We found that components of NF-κB pathway, including P65 and IκBα, and secretion of TNF-αwere upregulated upon LPS stimulation in intestinal epithelial cells. SDC1, especially through its unshed ectodomain, significantly lessened the upregulation extent. It also functioned in inhibiting migration of neutrophils by downregulating secretion of CXCL-1. Taken together, we conclude that suppressing SDC1 shedding from intestinal epithelial cells relieves severity of intestinal inflammation by inactivating NF-κB pathway and downregulating TNF-αexpression. These results indicate that the ectodomain of SDC1 might be the optional therapy for intestinal inflammation.

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Effect of Calcium on the Growth and Differentiation of Cultured Rat Esophageal Epithelial Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053383 ◽

1982 ◽

Vol 40 ◽

pp. 132-133

Author(s):

W.T. Gunning ◽

M.R. Marino ◽

M.S. Babcock ◽

G.D. Stoner

Keyword(s):

Epithelial Cells ◽

Cell Types ◽

Replication Rate ◽

Enzymatic Dissociation ◽

Growth Assay ◽

Epidermal Growth ◽

Fetal Bovine ◽

Esophageal Epithelial Cells ◽

Cellular Replication

The role of calcium in modulating cellular replication and differentiation has been described for various cell types. In the present study, the effects of Ca++ on the growth and differentiation of cultured rat esophageal epithelial cells was investigated.Epithelial cells were isolated from esophagi taken from 8 week-old male CDF rats by the enzymatic dissociation method of Kaighn. The cells were cultured in PFMR-4 medium supplemented with 0.25 mg/ml dialyzed fetal bovine serum, 5 ng/ml epidermal growth factor, 10-6 M hydrocortisone 10-6 M phosphoethanolamine, 10-6 M ethanolamine, 5 pg/ml insulin, 5 ng/ml transferrin, 10 ng/ml cholera toxin and 50 ng/ml garamycin at 36.5°C in a humidified atmosphere of 3% CO2 in air. At weekly intervals, the cells were subcultured with a solution containing 1% polyvinylpyrrolidone, 0.01% EGTA, and 0.05% trypsin. After various passages, the replication rate of the cells in PFMR-4 medium containing from 10-6 M to 10-3 M Ca++ was determined using a clonal growth assay.

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The role of differential phase contrast in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108027 ◽

1978 ◽

Vol 36 (1) ◽

pp. 176-177

Author(s):

E.M. Waddell ◽

J.N. Chapman ◽

R.P. Ferrier

Keyword(s):

Phase Contrast ◽

Practical Method ◽

Position Vector ◽

Differential Phase ◽

Pure Phase ◽

Differential Phase Contrast ◽

The Difference ◽

Image Position ◽

First Moment

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.

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