Human intrinsic choroidal neurons do not alter the expression of intrinsic markers in response to pressure

2021 ◽  
pp. bjophthalmol-2021-320211
Author(s):  
Christian Platzl ◽  
Alexandra Kaser-Eichberger ◽  
Heidi Wolfmeier ◽  
Andrea Trost ◽  
Falk Schroedl

BackgroundThe choroid is densely innervated by all parts of the autonomic nervous system and further harbours a network of local nerve cells, the intrinsic choroidal neurons (ICN). Their function in ocular control is currently unknown. While morphological data assume a role in intraocular pressure regulation, we here test if increased pressure on isolated choroids may activate ICN.MethodsDonor tissue was transferred into a pressurisable tissue culture chamber, and nasal and temporal choroid halves incubated for 1 or 4 hours, with pressures set to 15 or 50 mm Hg, followed by qRT-PCR expression analysis of the ICN-specific markers VIP, UCN, NOS1, UCH-L1. POL2-normalised data in the different pressure settings, incubation times and localisations were statistically analysed.ResultsThe presence of the ICN-specific markers VIP, UCN, NOS1, UCH-L1 was confirmed using immunohistochemistry, and mRNA of all markers was detected in all experimental conditions. Marker analysis revealed no significant changes of mRNA expression levels between 15 and 50 mm Hg in the different incubation times. When comparing all samples over all experimental conditions, a significant increase of VIP and NOS1 mRNA was detected in temporal versus nasal choroids.ConclusionIn this functional analysis of human ICN in vitro, higher amounts of VIP and NOS1 mRNA were detected in the temporal choroid, that is, the choroidal site with ICN accumulation. Further, our data indicate that elevated pressure is apparently not able to trigger ICN responses via the investigated markers. Alternative markers and stimuli need to be investigated in upcoming studies in order to unravel ICN function.

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Won-Jae Lee ◽  
Ryoung-Hoon Jeon ◽  
Si-Jung Jang ◽  
Ji-Sung Park ◽  
Seung-Chan Lee ◽  
...  

The identification of stable reference genes is a prerequisite for ensuring accurate validation of gene expression, yet too little is known about stable reference genes of porcine MSCs. The present study was, therefore, conducted to assess the stability of reference genes in porcine MSCs derived from bone marrow (BMSCs), adipose (AMSCs), and skin (SMSCs) with their in vitro differentiated cells into mesenchymal lineages such as adipocytes, osteocytes, and chondrocytes. Twelve commonly used reference genes were investigated for their threshold cycle (Ct) values by qRT-PCR. The Ct values of candidate reference genes were analyzed by geNorm software to clarify stable expression regardless of experimental conditions. Thus, Pearson’s correlation was applied to determine correlation between the three most stable reference genes (NF3) and optimal number of reference genes (NFopt). In assessment of stability of reference gene across experimental conditions by geNorm analysis, undifferentiated MSCs and each differentiated status into mesenchymal lineages showed slightly different results but similar patterns about more or less stable rankings. Furthermore, Pearson’s correlation revealed high correlation (r>0.9) between NF3and NFopt. Overall, the present study showed thatHMBS,YWHAZ,SDHA, andTBPare suitable reference genes for qRT-PCR in porcine MSCs.


Author(s):  
D. Chrétien ◽  
D. Job ◽  
R.H. Wade

Microtubules are filamentary structures found in the cytoplasm of eukaryotic cells, where, together with actin and intermediate filaments, they form the components of the cytoskeleton. They have many functions and show various levels of structural complexity as witnessed by the singlet, doublet and triplet structures involved in the architecture of centrioles, basal bodies, cilia and flagella. The accepted microtubule model consists of a 25 nm diameter hollow tube with a wall made up of 13 paraxial protofilaments (pf). Each pf is a string of aligned tubulin dimers. Some results have suggested that the pfs follow a superhelix. To understand how microtubules function in the cell an accurate model of the surface lattice is one of the requirements. For example the 9x2 architecture of the axoneme will depend on the organisation of its component microtubules. We should also note that microtubules with different numbers of pfs have been observed in thin sections of cellular and of in-vitro material. An outstanding question is how does the surface lattice adjust to these different pf numbers?We have been using cryo-electron microscopy of frozen-hydrated samples to study in-vitro assembled microtubules. The experimental conditions are described in detail in this reference. The results obtained in conjunction with thin sections of similar specimens and with axoneme outer doublet fragments have already allowed us to characterise the image contrast of 13, 14 and 15 pf microtubules on the basis of the measured image widths, of the the image contrast symmetry and of the amplitude and phase behaviour along the equator in the computed Fourier transforms. The contrast variations along individual microtubule images can be interpreted in terms of the geometry of the microtubule surface lattice. We can extend these results and make some reasonable predictions about the probable surface lattices in the case of other pf numbers, see Table 1. Figure 1 shows observed images with which these predictions can be compared.


1981 ◽  
Vol 45 (03) ◽  
pp. 290-293 ◽  
Author(s):  
Peter H Levine ◽  
Danielle G Sladdin ◽  
Norman I Krinsky

SummaryIn the course of studying the effects on platelets of the oxidant species superoxide (O- 2), Of was generated by the interaction of xanthine oxidase plus xanthine. Surprisingly, gel-filtered platelets, when exposed to xanthine oxidase in the absence of xanthine substrate, were found to generate superoxide (O- 2), as determined by the reduction of added cytochrome c and by the inhibition of this reduction in the presence of superoxide dismutase.In addition to generating Of, the xanthine oxidase-treated platelets display both aggregation and evidence of the release reaction. This xanthine oxidase induced aggreagtion is not inhibited by the addition of either superoxide dismutase or cytochrome c, suggesting that it is due to either a further metabolite of O- 2, or that O- 2 itself exerts no important direct effect on platelet function under these experimental conditions. The ability of Of to modulate platelet reactions in vivo or in vitro remains in doubt, and xanthine oxidase is an unsuitable source of O- 2 in platelet studies because of its own effects on platelets.


1997 ◽  
Vol 77 (05) ◽  
pp. 0975-0980 ◽  
Author(s):  
Angel Gálvez ◽  
Goretti Gómez-Ortiz ◽  
Maribel Díaz-Ricart ◽  
Ginés Escolar ◽  
Rogelio González-Sarmiento ◽  
...  

SummaryThe effect of desmopressin (DDAVP) on thrombogenicity, expression of tissue factor and procoagulant activity (PCA) of extracellular matrix (ECM) generated by human umbilical vein endothelial cells cultures (HUVEC), was studied under different experimental conditions. HUVEC were incubated with DDAVP (1, 5 and 30 ng/ml) and then detached from their ECM. The reactivity towards platelets of this ECM was tested in a perfusion system. Coverslips covered with DD A VP-treated ECMs were inserted in a parallel-plate chamber and exposed to normal blood anticoagulated with low molecular weight heparin (Fragmin®, 20 U/ml). Perfusions were run for 5 min at a shear rate of 800 s1. Deposition of platelets on ECMs was significantly increased with respect to control ECMs when DDAVP was used at 5 and 30 ng/ml (p <0.05 and p <0.01 respectively). The increase in platelet deposition was prevented by incubation of ECMs with an antibody against human tissue factor prior to perfusion. Immunofluorescence studies positively detected tissue factor antigen on DDAVP derived ECMs. A chromogenic assay performed under standardized conditions revealed a statistically significant increase in the procoagulant activity of the ECMs produced by ECs incubated with 30 ng/ml DDAVP (p <0.01 vs. control samples). Northern blot analysis revealed increased levels of tissue factor mRNA in extracts from ECs exposed to DDAVP. Our data indicate that DDAVP in vitro enhances platelet adhesion to the ECMs through increased expression of tissue factor. A similar increase in the expression of tissue factor might contribute to the in vivo hemostatic effect of DDAVP.


2019 ◽  
Vol 26 (5) ◽  
pp. 339-347 ◽  
Author(s):  
Dilani G. Gamage ◽  
Ajith Gunaratne ◽  
Gopal R. Periyannan ◽  
Timothy G. Russell

Background: The dipeptide composition-based Instability Index (II) is one of the protein primary structure-dependent methods available for in vivo protein stability predictions. As per this method, proteins with II value below 40 are stable proteins. Intracellular protein stability principles guided the original development of the II method. However, the use of the II method for in vitro protein stability predictions raises questions about the validity of applying the II method under experimental conditions that are different from the in vivo setting. Objective: The aim of this study is to experimentally test the validity of the use of II as an in vitro protein stability predictor. Methods: A representative protein CCM (CCM - Caulobacter crescentus metalloprotein) that rapidly degrades under in vitro conditions was used to probe the dipeptide sequence-dependent degradation properties of CCM by generating CCM mutants to represent stable and unstable II values. A comparative degradation analysis was carried out under in vitro conditions using wildtype CCM, CCM mutants and two other candidate proteins: metallo-β-lactamase L1 and α -S1- casein representing stable, borderline stable/unstable, and unstable proteins as per the II predictions. The effect of temperature and a protein stabilizing agent on CCM degradation was also tested. Results: Data support the dipeptide composition-dependent protein stability/instability in wt-CCM and mutants as predicted by the II method under in vitro conditions. However, the II failed to accurately represent the stability of other tested proteins. Data indicate the influence of protein environmental factors on the autoproteolysis of proteins. Conclusion: Broader application of the II method for the prediction of protein stability under in vitro conditions is questionable as the stability of the protein may be dependent not only on the intrinsic nature of the protein but also on the conditions of the protein milieu.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Skaidre Jankovskaja ◽  
Johan Engblom ◽  
Melinda Rezeli ◽  
György Marko-Varga ◽  
Tautgirdas Ruzgas ◽  
...  

AbstractThe tryptophan to kynurenine ratio (Trp/Kyn) has been proposed as a cancer biomarker. Non-invasive topical sampling of Trp/Kyn can therefore serve as a promising concept for skin cancer diagnostics. By performing in vitro pig skin permeability studies, we conclude that non-invasive topical sampling of Trp and Kyn is feasible. We explore the influence of different experimental conditions, which are relevant for the clinical in vivo setting, such as pH variations, sampling time, and microbial degradation of Trp and Kyn. The permeabilities of Trp and Kyn are overall similar. However, the permeated Trp/Kyn ratio is generally higher than unity due to endogenous Trp, which should be taken into account to obtain a non-biased Trp/Kyn ratio accurately reflecting systemic concentrations. Additionally, prolonged sampling time is associated with bacterial Trp and Kyn degradation and should be considered in a clinical setting. Finally, the experimental results are supported by the four permeation pathways model, predicting that the hydrophilic Trp and Kyn molecules mainly permeate through lipid defects (i.e., the porous pathway). However, the hydrophobic indole ring of Trp is suggested to result in a small but noticeable relative increase of Trp diffusion via pathways across the SC lipid lamellae, while the shunt pathway is proposed to slightly favor permeation of Kyn relative to Trp.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 426.1-426
Author(s):  
T. Hügle ◽  
S. Nasi ◽  
D. Ehirchiou ◽  
P. Omoumi ◽  
A. So ◽  
...  

Background:Fibrin(ogen) maintains inflammation in various disorders but has never been linked to cartilage damage in rheumatoid arthritis (RA) or other forms of inflammatory arthritis.Objectives:To investigate the role of fibrin deposition on cartilage integrity in arthritis.Methods:Fibrin deposition on knee cartilage was analyzed by immunohistochemistry in RA patients and in murine adjuvant-induced arthritis (AIA). In chondrocytes, fibrinogen expression (Fgα, Fgβ, Fgγ) and procoagulant activity were evaluated by qRT-PCR and turbidimetry respectively. Fibrin-induced catabolic genes were assessed by qRT-PCR in chondrocytes. Fibrin-mediated chondro-synovial adhesion (CSA) with subsequent cartilage tears was studied in co-cultures of human RA cartilage with autologous synoviocytes, in the AIA model, and by MRI. The link between fibrin and calcification was examined in human RA cartilage stained for calcific deposits and in vitro in fibrinogen-stimulated chondrocytes.Results:Fibrin deposition on cartilage correlated with the severity of cartilage damage in human RA explants and in AIA wildtype (WT) mice, while fibrinogen deficient (Fg-/-) mice were protected. Accordingly, fibrin upregulated catabolic enzymes (Adamts5 and Mmp13) in chondrocytes. Secondly, CSA was present in fibrin-rich and damaged cartilage in AIA WT but not in Fg-/- mice. In line, autologous human synoviocytes, cultured on RA cartilage explants, adhered exclusively to fibrin-positive degraded areas. Gadolinium-enhanced MRI of human joints showed contrast-enhancement along cartilage surface in RA patients but not in controls. Finally, fibrin co-localized with calcification in human RA cartilage and triggered chondrocyte mineralization inducing pro-calcification genes (Anx5, Pit1, Pc1) and cytokine (IL-6). Although at a much lesser extent, we observed similar fibrin-mediated mechanisms in osteoarthritis (OA).Conclusion:Fibrin deposition directly impacts on cartilage integrity via induction of catabolism, mechanical stress, and calcification. Potentially, fibrin is a key factor of cartilage damage occurring in RA as a secondary consequence of inflammation.Disclosure of Interests:None declared


BMC Neurology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yi Wang ◽  
Guogang Dai ◽  
Ling Jiang ◽  
Shichuan Liao ◽  
Jiao Xia

Abstract Background Although the pathology of sciatica has been studied extensively, the transcriptional changes in the peripheral blood caused by sciatica have not been characterized. This study aimed to characterize the peripheral blood transcriptomic signature for sciatica. Methods We used a microarray to identify differentially expressed genes in the peripheral blood of patients with sciatica compared with that of healthy controls, performed a functional analysis to reveal the peripheral blood transcriptomic signature for sciatica, and conducted a network analysis to identify key genes that contribute to the observed transcriptional changes. The expression levels of these key genes were assessed by qRT-PCR. Results We found that 153 genes were differentially expressed in the peripheral blood of patients with sciatica compared with that of healthy controls, and 131 and 22 of these were upregulated and downregulated, respectively. A functional analysis revealed that these differentially expressed genes (DEGs) were strongly enriched for the inflammatory response or immunity. The network analysis revealed that a group of genes, most of which are related to the inflammatory response, played a key role in the dysregulation of these DEGs. These key genes are Toll-like receptor 4, matrix metallopeptidase 9, myeloperoxidase, cathelicidin antimicrobial peptide, resistin and Toll-like receptor 5, and a qRT-PCR analysis validated the higher transcript levels of these key genes in the peripheral blood of patients with sciatica than in that of healthy controls. Conclusion We revealed inflammatory characteristics that serve as a peripheral blood transcriptomic signature for sciatica and identified genes that are essential for mRNA dysregulation in the peripheral blood of patients with sciatica.


Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 328 ◽  
Author(s):  
Claudio Salaris ◽  
Melania Scarpa ◽  
Marina Elli ◽  
Alice Bertolini ◽  
Simone Guglielmetti ◽  
...  

SARS-CoV-2 is a newly emerging virus that currently lacks curative treatments. Lactoferrin (LF) is a naturally occurring non-toxic glycoprotein with broad-spectrum antiviral, immunomodulatory and anti-inflammatory effects. In this study, we assessed the potential of LF in the prevention of SARS-CoV-2 infection in vitro. Antiviral immune response gene expression was analyzed by qRT-PCR in uninfected Caco-2 intestinal epithelial cells treated with LF. An infection assay for SARS-CoV-2 was performed in Caco-2 cells treated or not with LF. SARS-CoV-2 titer was determined by qRT-PCR, plaque assay and immunostaining. Inflammatory and anti-inflammatory cytokine production was determined by qRT-PCR. LF significantly induced the expression of IFNA1, IFNB1, TLR3, TLR7, IRF3, IRF7 and MAVS genes. Furthermore, LF partially inhibited SARS-CoV-2 infection and replication in Caco-2 intestinal epithelial cells. Our in vitro data support LF as an immune modulator of the antiviral immune response with moderate effects against SARS-CoV-2 infection.


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