Search bioRxiv⌕ Search

Biology subjects

Kocsy, K.

Publications and source records attributed to Kocsy, K..

5 recordsLinked to original sources

Targeting COL4A1-Related Small Vessel Disease: Repurposed Pharmacotherapies for Genetic Vasculopathies

COL4A1-related disorders cause early-onset stroke, intracerebral haemorrhage, visual impairment and kidney disease, often affecting children and young adults, yet no disease-modifying therapies exist. These disorders arise from pathogenic COL4A1 variants that disrupt type IV collagen and impair small-vessel integrity, leading to cerebral small-vessel disease and endothelial dysfunction. We performed a mechanism-guided screen in human brain endothelial cells using a CRISPR-engineered COL4A1 p.G755R line and patient-specific COL4A1 p.G773R iPSC-derived endothelial cells. Simvastatin, L-carnosine, and XPD-101 restored impaired endothelial proliferation, migration, and other markers of endothelial function, including transendothelial electrical resistance (TEER). In a Col4a1Svc/+ mouse model, simvastatin increased pre-weaning survival, improved functional behaviour and reduced cerebral microhaemorrhage burden. These findings identify mechanism-informed candidates that rescue COL4A1-mutant endothelial dysfunction in vitro, with simvastatin demonstrating in vivo efficacy, supporting prioritisation for further preclinical development.

molecular biology↗

Reprogramming Human Inflammatory Macrophages in Symptomatic Carotid Stenosis: Potential Mechanisms for Stabilisation of Atherosclerotic Carotid Plaques

BackgroundInflammation is a precursor to atherosclerotic plaque destabilisation, leading to ischaemic events such as stroke. Macrophage phenotypes can be altered by the microenvironment, and certain anti-inflammatory agents may, therefore, stabilise plaques and reduce the risk of recurrent ischaemic events. MethodsThirteen carotid plaques were obtained from stroke/ Transient Ischaemic Attack (TIA) patients undergoing carotid endarterectomy. An immunofluorescence stain was used to identify common macrophage markers (pan macrophage: CD68, pro-inflammatory: CD86, anti-inflammatory: MRC1), and a novel analysis technique was used to measure the prevalence of macrophage phenotypes in carotid plaques in relation to other histological features of instability. An in vitro model of human blood-derived macrophages was also developed to evaluate the effect of statins and glucocorticoids on macrophage-specific markers using RT-qPCR, Western Blot and immunofluorescence stain. The physiological effect of dexamethasone was further evaluated on macrophages and human carotid plaques cultured ex vivo. ResultsThe macrophage population (CD68+) in the carotid plaques was dominated by "double-positive" (CD86+MRC1+) macrophages (67.8%), followed by "M1-like" (CD86+MRC1-) (16.5%), "M2-like" (CD86-MRC1+) (8.7%) and "double-negative" (CD86-MRC1-) (7.0%) macrophages. M1-like macrophages were more prevalent in unstable plaque sections than stable ones (p=0.0022). Exposure to dexamethasone increased macrophage MRC1 gene expression in vitro and ex vivo. Dexamethasone also reduced Oxidised Low-Density Lipoprotein Receptor 1 (OLR1) gene and protein expression, leading to a decreased ox-LDL uptake in foam cell assays. This was, in turn, associated with reduced lipid uptake in macrophages, as shown by Oil Red O staining. ConclusionsHuman macrophages may be "switched" to a less inflammatory phenotype by exposure to clinically relevant concentrations of glucocorticoid, potentially mediated by a reduction in Oxidised LDL uptake. This effect was not observed following macrophage exposure to statins. Glucocorticoids may have a future role in preventing ischaemic events in patients with advanced atherosclerosis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=77 SRC="FIGDIR/small/598440v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@bb389borg.highwire.dtl.DTLVardef@18151b8org.highwire.dtl.DTLVardef@11c28a1org.highwire.dtl.DTLVardef@1af6acd_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIA high prevalence (68% in this study) of carotid plaque macrophages express both pro-inflammatory (CD86) and anti-inflammatory (MRC1) markers. These may represent a novel macrophage population. C_LIO_LIHuman macrophages may be "reprogrammed" to a less inflammatory phenotype following exposure to glucocorticoids. C_LIO_LIDexamethasone increased MRC1 and decreased OLR1 expression in macrophages derived from human blood samples in vitro and in cells derived from cultured human carotid plaque tissue ex vivo. This was associated with reduced oxLDL uptake and reduced lipid accumulation in the macrophages. C_LIO_LIDexamethasone has the potential to stabilise carotid atherosclerotic plaques in humans. C_LI

cell biology↗

Genome-wide association and functional analyses identify CASC20 and KIF26B as target loci in heterotopic ossification

Heterotopic ossification (HO) is bone formation that occurs after trauma within tissues that do not normally have the property of ossification, resulting in pain and disability. The genetic architecture of HO remains unclear. In the first genome-wide association studies of this disease, we identify the human-only long non-coding RNA-encoding gene CASC20 as a robust, replicating susceptibility locus for HO and KIF26B as a potential severity locus. We find that both CASC20 and KIF26B are expressed in human bone. Both CASC20 and KIF26B expression is upregulated upon BMP2 induced osteogenic differentiation in primary human mesenchymal stem cells, followed by RUNX2 and OSTERIX upregulation and mineralised nodule formation. A CRISPR-Cas9 mediated knockout of Kif26b inhibits BMP2-induced Runx2, Sp7/Osterix, Col1A1, Alp, and Bglap/Osteocalcin expression in a murine myocyte model of osteogenic trans-differentiation, and prevents mineralised nodule formation. These studies provide the first insights into the heritable biology of common, complex HO.

genetics↗

Mitogenomic data indicate admixture components of Asian Hun and Srubnaya origin in the Hungarian Conquerors

It has been widely accepted that the Finno-Ugric Hungarian language, originated from proto Uralic people, was brought into the Carpathian Basin by the Hungarian Conquerors. From the middle of the 19th century this view prevailed against the deep-rooted Hungarian Hun tradition, maintained in folk memory as well as in Hungarian and foreign written medieval sources, which claimed that Hungarians were kinsfolk of the Huns. In order to shed light on the genetic origin of the Conquerors we sequenced 102 mitogenomes from early Conqueror cemeteries and compared them to sequences of all available databases. We applied novel population genetic algorithms, named Shared Haplogroup Distance and MITOMIX, to reveal past admixture of maternal lineages. Phylogenetic and population genetic analysis indicated that more than one third of the Conqueror maternal lineages were derived from Central-Inner Asia and their most probable ultimate sources were the Asian Huns. The rest of the lineages most likely originated from the Bronze Age Potapovka-Poltavka-Srubnaya cultures of the Pontic-Caspian steppe, which area was part of the later European Hun empire. Our data give support to the Hungarian Hun tradition and provides indirect evidence for the genetic connection between Asian and European Huns. Available data imply that the Conquerors did not have a major contribution to the gene pool of the Carpathian Basin, raising doubts about the Conqueror origin of Hungarian language.

genetics↗

Revising mtDNA haplotypes of the ancient Hungarian conquerors with next generation sequencing

As part of the effort to create a high resolution representative sequence database of the medieval Hungarian conquerors we have resequenced the entire mtDNA genome of 24 published ancient samples with Next Generation Sequencing, whose haplotypes had been previously determined with traditional PCR based methods. We show that PCR based methods are prone to erroneous haplotype or haplogroup determination due to ambiguous sequence reads, and many of the resequenced samples had been classified inaccurately. The SNaPshot method applied with published ancient DNA authenticity criteria is the most straightforward and cheapest PCR based approach for testing a large number of coding region SNP-s, which greatly facilitates correct haplogroup determination.

genetics↗