fredag 6 maj 2022

Ny forskningsrapport från England

Igår publicerades en ny studie angående Systemisk Skleros.4 forskare från Leeds, England har studerat hur det kroppsegna enzymet Hemeoxygenase-1 (HO-1) påverkar en insjuknad patients hjärt och kärlsystem.
Systemisk Skleros är en dödlig sjukdom (terminal) som det idag inte finns något bra botemedel mot.
Den forskning som bedrivits i ämnet är knapp men vetenskapen har konstaterat att sjukdomen tar sin början i kroppens immunförsvar.Där sker en utveckling vilket gör att immunförsvaret ser kroppens egna vävnader som "fiender" och processer startas för att (felaktigt) påverka dessa tyvärr i en negativ riktning.

 

Socialstyrelsen har en bra beskrivning av sjukdomen.Från den texten klipper jag utvalda delar.

Systemisk skleros är en ovanlig bindvävssjukdom som karaktäriseras av förändrat immunförsvar, försämrad blodcirkulation och ökad bindvävsproduktion i hud och inre organ, framför allt i mag-tarmkanal, lungor, hjärta och njurar. Sjukdomen kallades tidigare sklerodermi (skleros=förhårdning, derma=hud).
Systemisk skleros är en autoimmun sjukdom, vilket innebär att kroppens immunförsvar felaktigt riktas mot de egna vävnaderna. Trots att grundorsaken till sjukdomen är okänd är det relativt väl känt vad som bidrar till att den utvecklas.

Inflammatoriska celler (makrofager och lymfocyter) ansamlas kring blodkärlen. Dessa celler utsöndrar signalsubstanser (cytokiner, exempelvis TGFβ) som aktiverar bindvävsceller (fibroblaster) för att dessa ska producera bindvävsmolekyler, till exempel kollagen. Fibroblaster ska normalt aktiveras för att reparera skador, som vid sårläkning, eller när bindvävsmolekylerna successivt ska bytas ut. Vid systemisk skleros bildas onormalt stora mängder bindvävsproteiner i hud och inre organ. Bindvävens normala funktion är att ge kroppens vävnader elasticitet, stöd och hållfasthet. Organ som vid systemisk skleros innehåller ökade mängder bindväv, som hud och lungor, blir stela och mindre elastiska.

Onormala immunreaktioner sker, med produktion av antikroppar riktade mot kroppsegna strukturer (autoantikroppar), till exempel mot ämnen i cellkärnor.
Det finns ännu ingen botande behandling för systemisk skleros. Insatserna inriktas på att lindra symtomen genom att dämpa inflammationer och förbättra cirkulationen. Eftersom sjukdomen kan påverka inre organ är det viktigt att organfunktionen undersöks noga och att vård och behandling ges tidigt i
sjukdomsförloppet. 

Men till de engelska forskarnas studie.
Front. Physiol., 05 May 2022
 
Systemic sclerosis (SSc) is a terminal disease characterized by vasculopathy, tissue fibrosis, and autoimmunity. Although the exact etiology of SSc remains unknown, endothelial dysfunction, oxidative stress, and calcium handling dysregulation have been associated with a large number of SSc-related complications such as neointima formation, vasculogenesis, pulmonary arterial hypertension, impaired angiogenesis, and cardiac arrhythmias. Hemeoxygenase-1 (HO-1) is an antioxidant enzyme involved in multiple biological actions in the cardiovascular system including vascular tone, angiogenesis, cellular proliferation, apoptosis, and oxidative stress. The aim of this work was to investigate the physiological role of HO-1 and its relevance in the cardiovascular complications occurring in SSc. We found that, in early phases of SSc, the expression of HO-1 in dermal fibroblast is lower compared to those isolated from healthy control individuals. This is particularly relevant as reduction of the HO-1/CO signaling pathway is associated with endothelial dysfunction and vasculopathy. We show evidence of the role of HO-1/carbon monoxide (CO) signaling pathway in calcium handling. Using an in vitro model of pulmonary arterial hypertension (PAH) we investigated the role of HO-1 in Ca2+ mobilization from intracellular stores. Our results indicate that HO-1 regulates calcium release from intracellular stores of human pulmonary arterial endothelial cells. We interrogated the activity of HO-1 in angiogenesis using an organotypic co-culture of fibroblast-endothelial cell. Inhibition of HO-1 significantly reduced the ability of endothelial cells to form tubules. We further investigated if this could be associated with cell motility or migration of endothelial cells into the extracellular matrix synthesized by fibroblasts.
 
By mean of holographic imaging, we studied the morphological and functional features of endothelial cells in the presence of an HO-1 activator and selective inhibitors. Our results demonstrate that inhibition of HO-1 significantly reduces cell proliferation and cell motility (migration) of cultured endothelial cells, whilst activation of HO-1 does not modify either morphology, proliferation or motility. In addition, we investigated the actions of CO on the Kv7.1 (KCQN1) channel current, an important component of the cardiac action potential repolarization. Using electrophysiology (whole-cell patch-clamp in a recombinant system overexpressing the KCQN1 channel), we assessed the regulation of KCQN1 by CO. CORM-2, a CO donor, significantly reduced the Kv7.1 current, suggesting that HO-1/CO signaling may play a role in the modulation of the cardiac action potential via regulation of this ion channel. In summary, our results indicate a clear link between: 1) downregulation of HO-1/CO signaling; and 2) pathophysiological processes occurring in early phases of SSc, such as calcium homeostasis dysregulation, impaired angiogenesis and cardiac arrhythmias. A better understanding of the canonical actions (mainly due to the biological actions of CO), and non-canonical actions of HO-1, as well as the interaction of HO-1/CO signaling with other gasotransmitters in SSc will contribute to the development of novel therapeutic approaches.
 

Materials and Methods (urval)

Live Holographic Imaging

Holographic microscopy analysis was performed to investigate the morphological and functional changes caused by inducers and inhibitors of HO-1 in endothelial cells. Holographic imaging recorded in real-time was used to monitor morphological (cell area, optical thickness, and optical volume) and functional (cell motility, cell tracking, and cell migration) parameters using the Holomonitor App Suite (Phase Holographic Imaging PHI AB). HUVECs were seeded at low confluency (100 k cells per well) onto 6-well plates (Sarstedt, Germany). Drugs and VEGF were added to the media at the concentration indicated in Figure 4 (25 ng/ml VEGF, 10 µM CoPPIX, and 1 µM ZnPPIX). For every independent experiment, one control well (absence of drugs or VEGF) was included in each plate. 

The plate was placed onto the xy motorised stage of a HoloMonitor M4 Microscope, set up inside an incubator using Phi HoloLids™ imaging covers (PHI, phase holographic imaging), previously sterilised in 70% EtOH, to optimise the acquisition quality of the holographic images. After automatic calibration of the background and microscope objective, a minimum of three fields/coordinates per well, randomly assigned by the software, were focused on. Holographic images were recorded at an interval of 5 min over 48 h using the HoloMonitor M4 (Phase Holographic Imaging PHI AB, Lund, Sweden) inside the cell-culture incubator (37°C, 5% CO2). Post-acquisition, the images were analysed applying the “Otsu mask”, where a threshold was set to distinguish cells from the bottom of the well (cell segmentation), allowing for automatic cell identification. Automatic cell number assignment allowed for individual cell tracking over time, which was double-checked manually as described in (Owston et al., 2019). All outputs were exported into Excel files and plotted using Prism 9 (GraphPad).

Resultatet forskarna kom fram till beskrivs enligt följande :

- As fibroblasts are responsible for the production and secretion of TGF-β (the main pro-fibrotic factor in SSc), we investigated the expression levels of HO-1 in healthy and SSc fibroblasts. Although expression levels of HO-1 in unstimulated SSc fibroblasts are not significantly different from healthy fibroblasts, exposure to 10 µM TGF-β for 24 h significantly inhibited the expression of HO-1 in healthy but not SSc fibroblasts (Figure 1A), indicating that the expression of HO-1 is already influenced by the elevated endogenous production of TGF-β in SSc fibroblasts.

Glasklart, eller hur? 

Forskarna avslutar rapporten med att tacka PHI`s repr Amendeep Dhillon.

Acknowledgments
We are extremely grateful to Amandeep Dhillon (Phase Holographic Imaging PHI AB) for lending the University of Bradford the HoloMonitor® M4 to conduct the cellular morphology and migration studies.
 
Min kommentar
Ånyo ett nytt användningsområde för HoloMonitor kan denna studie visa på.Tekniken firar segrar medan (aktie)marknaden fortfarande surar.Dock finns små tecken på att det kommer förändras inom kort.
 
                                                Mvh the99
 
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