Hydrogen Sulfide Is a Novel Protector of the Retinal Glycocalyx and Endothelial Permeability Barrier

This is the final version. Available on open access from Frontiers Media via the DOI in this recordData Availability Statement: The original contributions presented in the study are included in the article/supplementary material. The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Significantly reduced levels of the anti-inflammatory gaseous transmitter hydrogen sulfide (H2S) are observed in diabetic patients and correlate with microvascular dysfunction. H2S may protect the microvasculature by preventing loss of the endothelial glycocalyx. We tested the hypothesis that H2S could prevent or treat retinal microvascular endothelial dysfunction in diabetes. Bovine retinal endothelial cells (BRECs) were exposed to normal (NG, 5.5 mmol/L) or high glucose (HG, 25 mmol/L) ± the slow-release H2S donor NaGYY4137 in vitro. Glycocalyx coverage (stained with WGA-FITC) and calcein-labeled monocyte adherence were measured. In vivo, fundus fluorescein angiography (FFA) was performed in normal and streptozotocin-induced (STZ) diabetic rats. Animals received intraocular injection of NaGYY4137 (1 μM) or the mitochondrial-targeted H2S donor AP39 (100 nM) simultaneously with STZ (prevention) or on day 6 after STZ (treatment), and the ratio of interstitial to vascular fluorescence was used to estimate apparent permeability. NaGYY4137 prevented HG-induced loss of BREC glycocalyx, increased monocyte binding to BRECs (p ≤ 0.001), and increased overall glycocalyx coverage (p ≤ 0.001). In rats, the STZ-induced increase in apparent retinal vascular permeability (p ≤ 0.01) was significantly prevented by pre-treatment with NaGYY4137 and AP39 (p < 0.05) and stabilized by their post-STZ administration. NaGYY4137 also reduced the number of acellular capillaries (collagen IV + /IB4-) in the diabetic retina in both groups (p ≤ 0.05). We conclude that NaGYY4137 and AP39 protected the retinal glycocalyx and endothelial permeability barrier from diabetes-associated loss of integrity and reduced the progression of diabetic retinopathy (DR). Hydrogen sulfide donors that target the glycocalyx may therefore be a therapeutic candidate for DR.Medical Research Council (MRC)British Heart FoundationRoyal SocietyBrian Ridge ScholarshipNational Eye Research CentreMasonic Charitable Foundatio

3D matrix adhesion feedback controls nuclear force coupling to drive invasive cell migration

Cell invasion is a multi-step process, initiated by the acquisition of a migratory phenotype and the ability to move through complex 3D extracellular environments. We determine the composition of cell-matrix adhesion complexes of invasive breast cancer cells in 3D matrices and identify an interaction complex required for invasive migration. bPix and myosin18A (Myo18A) drive polarized recruitment of non-muscle myosin 2A (NM2A) to adhesion complexes at the tips of protrusions. Actomyosin force engagement then displaces the Git1-bPix complex from paxillin, establishing a feedback loop for adhesion maturation. We observe active force transmission to the nucleus during invasive migration that is needed to pull the nucleus forward. The recruitment of NM2A to adhesions creates a non-muscle myosin isoform gradient, which extends from the protrusion to the nucleus. We postulate that this gradient facilitates coupling of cell-matrix interactions at the protrusive cell front with nuclear movement, enabling effective invasive migration and front-rear cell polarity

Genome-wide fitness analyses of the foodborne pathogen Campylobacter jejuni in in vitro and in vivo models.

Campylobacter is the most common cause of foodborne bacterial illness worldwide. Faecal contamination of meat, especially chicken, during processing represents a key route of transmission to humans. There is a lack of insight into the mechanisms driving C. jejuni growth and survival within hosts and the environment. Here, we report a detailed analysis of C. jejuni fitness across models reflecting stages in its life cycle. Transposon (Tn) gene-inactivation libraries were generated in three C. jejuni strains and the impact on fitness during chicken colonisation, survival in houseflies and under nutrient-rich and -poor conditions at 4 °C and infection of human gut epithelial cells was assessed by Tn-insertion site sequencing (Tn-seq). A total of 331 homologous gene clusters were essential for fitness during in vitro growth in three C. jejuni strains, revealing that a large part of its genome is dedicated to growth. We report novel C. jejuni factors essential throughout its life cycle. Importantly, we identified genes that fulfil important roles across multiple conditions. Our comprehensive screens showed which flagella elements are essential for growth and which are vital to the interaction with host organisms. Future efforts should focus on how to exploit this knowledge to effectively control infections caused by C. jejuni.This work was funded by Biotechnology and Biological Sciences Research Council (http://www.bbsrc.ac.uk) grant BB/K004514/1. D.P.W. was funded by a Wellcome Trust (https://wellcome.ac.uk) Infection and Immunity PhD rotation studentship. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

CETP gene TaqIB polymorphism and plasma lipids in patients with overweight and obesity

Wprowadzenie. Obecnie prowadzone badania wskazują na wzrost zgonów u osób z niskim stężeniem cholesterolu w surowicy, które spowodowane jest zmniejszaniem frakcji lipoprotein o wysokiej gęstości (HDL-C) i lipoprotein o niskiej gęstości (LDL-C). Cel. Celem pracy była ocena związku pomiędzy polimorfizmem TaqIB genu CETP, a stężeniami wybranych parametrów gospodarki lipidowej u pacjentów z nadwagą i otyłością. Materiał i metoda. Badaniami objęto 73 osoby w wieku 24-68 lat. Otyłość androidalną stwierdzono u 90,4% kobiet, w tym u 66,7% ze stężeniem HDL-C powyżej 50 mg/dL. Wyniki. Najwięcej z otyłością brzuszną było heterozygot B1B2 (38,1%). Otyłość brzuszna występowała u 48,4% mężczyzn, w tym u 25,8% heterozygot B1B2 oraz u 67,7% z HDL>40mg/dl. Stwierdzono, większe nieistotne statystycznie stężenie TG, TC, LDL-C, procentowej zawartości masy tkanki tłuszczowej (%FM) u pacjentów z genotypem B2B2 w porównaniu do osób z genotypem B1B1 i B1B2. U kobiet wyższe stężenie TC, LDL-C oraz HDL-C stwierdzono w przypadku obecności genotypu B1B2, natomiast większe stężenie wszystkich badanych frakcji lipidowych wykazali mężczyźni z genotypem B2B2, u których stwierdzono także największą zawartość %FM. Wnioski. Uzyskane wyniki wskazują, że u otyłych mężczyzn polimorfizm TagIB może być niezależnym czynnikiem wpływającym na stężenie HDL-cholesterolu.Background. Ongoing research shows an increase in mortality in patients with low levels of serum cholesterol, which is caused by decreasing the fraction of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein (LDL-C). Objective. The aim of our study was to assess the relationship between the CETP gene TaqI polymorphism and concentrations of selected parameters of lipid metabolism in patients with overweight and obesity. Materials and method. The study involved 73 people aged 24-68 years. Android obesity was found in 90.4% of women, including 66.7% in the HDL-C levels above 50 mg / dL. Results. Most of abdominal obesity was the B1B2 heterozygotes (38.1%). Abdominal obesity was present in 48.4% of men, including 25.8% in B1B2 heterozygotes and in 67.7% of HDL> 40mg/dl. It was found statistically insignificant higher levels of TG, TC, LDL-C, the percentage of fat mass (% FM)in patients with genotype B2B2 compared to those with genotype B1B1 and B1B2. In women, higher levels of TC, LDL-C and HDL-C were found in the presence of B1B2 genotype, whereas a higher concentration of all lipid fractions studied showed the men with the B2B2 genotype, who also had the highest % FM. Conclusions. The results indicate that in obese men TagIB polymorphism may be an independent factor influencing HDLcholesterol

3D matrix adhesion feedback controls nuclear force coupling to drive invasive cell migration.

Cell invasion is a multi-step process, initiated by the acquisition of a migratory phenotype and the ability to move through complex 3D extracellular environments. We determine the composition of cell-matrix adhesion complexes of invasive breast cancer cells in 3D matrices and identify an interaction complex required for invasive migration. βPix and myosin18A (Myo18A) drive polarized recruitment of non-muscle myosin 2A (NM2A) to adhesion complexes at the tips of protrusions. Actomyosin force engagement then displaces the Git1-βPix complex from paxillin, establishing a feedback loop for adhesion maturation. We observe active force transmission to the nucleus during invasive migration that is needed to pull the nucleus forward. The recruitment of NM2A to adhesions creates a non-muscle myosin isoform gradient, which extends from the protrusion to the nucleus. We postulate that this gradient facilitates coupling of cell-matrix interactions at the protrusive cell front with nuclear movement, enabling effective invasive migration and front-rear cell polarity