Metabolic Response in Endothelial Cells to Catecholamine Stimulation Associated with Increased Vascular Permeability

Disruption to endothelial cell homeostasis results in an extensive variety of human pathologies that are particularly relevant to major trauma. Circulating catecholamines, such as adrenaline and noradrenaline, activate endothelial adrenergic receptors triggering a potent response in endothelial function. The regulation of the endothelial cell metabolism is distinct and profoundly important to endothelium homeostasis. However, a precise catalogue of the metabolic alterations caused by sustained high catecholamine levels that results in endothelial dysfunction is still underexplored. Here, we uncover a set of up to 46 metabolites that exhibit a dose–response relationship to adrenaline-noradrenaline equimolar treatment. The identified metabolites align with the glutathione-ascorbate cycle and the nitric oxide biosynthesis pathway. Certain key metabolites, such as arginine and reduced glutathione, displayed a differential response to treatment in early (4 h) compared to late (24 h) stages of sustained stimulation, indicative of homeostatic metabolic feedback loops. Furthermore, we quantified an increase in the glucose consumption and aerobic respiration in endothelial cells upon catecholamine stimulation. Our results indicate that oxidative stress and nitric oxide metabolic pathways are downstream consequences of endothelial cell stimulation with sustained high levels of catecholamines. A precise understanding of the metabolic response in endothelial cells to pathological levels of catecholamines will facilitate the identification of more efficient clinical interventions in trauma patients.     

Light sensitivity of colourants used in alcoholic beverages

Quantum yields for photobleaching in ethanol solutions of Hexacol Red 2G Supra (E 128), Hexacol Sunset Yellow FCF Supra (E 110), caramel colour (E 150) and Liquid Red Colour (E 128) based on carminic acid, have been determined at 25° C in continuous photolysis experiments using monochromatic light at each of three wavelengths 334 nm, 366 nm and 436 nm, in order to obtain an objektive measure of the sensitivity to ultraviolet and visible light of colourants used in alcoholic beverages. For photobleaching of carminic acid from Liquid Red Colour in fruit wine [pH 3.1, with 15% (v/v) ethanol] quantum yield was determined as 2.1·10^–2 mol·einstein^–1 for 334 nm irradiation, 1.3·10^–3 mol·einstein^–1 for 366 nm irradiation and 5.6·10^–5 mol·einstein^–1 for 436 nm irradiation, respectively. For Hexacol Sunset Yellow FCF Supra in fruit wine, the quantum yield for 334 nm irradiation was determined as 5.9·10^–4 mol·einstein^–1 and for 366 nm irradiation as 2.4·10^–4 mol·einstein^–1. Hexacol Red 2G Supra in fruit wine had a quantum yield of 3.7·10^–5 mol·einstein^–1 for 366 nm irradiation. For Hexacol Red 2G Supra and Hexacol Sunset Yellow FCF Supra for 436 nm irradiation and for Hexacol Red 2G Supra for 334 nm irradiation the quantum yields were less than 10^–6 mol·einstein^–1. The following order was determined for light sensitivity in fruit wine (366 nm light): Liquid Red Colour > Hexacol Sunset Yellow FCF Supra > Hexacol Red 2G Supra. The caramel colour in aquavit [pH 7.1, with 42% (v/v) ethanol] was moderately sensitive to light with a quantum yield almost independent of irradiation wavelength. Relative quantum yields were determined as 1.6 for 334 nm irradiation, 1.0 for 366 nm and 1.0 for 436 nm irradiation. The latter value corresponded to 2.6 g caramel per einstein absorbed.

---

Lichtempfindlichkeit von Farbstoffen in alkoholischen Getränken

Zusammenfassung Um einen objektiven Wert für die Empfindlichkeit von Farbstoffen in alkoholischen Getränken gegenüber ultraviolettem und sichtbarem Licht festlegen zu können, wurde die Quantenausbeute für Photobleichung in ethanolischen Lösungen von Hexacol Red 2G Supra (E 128), Hexacol Sunset Yellow FCF Supra (E110), Caramel Farbe (E 150) und Liquid Red Colour (E 128; auf Carminsäure basieren) bei 25 °C in kontinuierlichen Photolyse-Experimenten mit monochromatischem Licht mit den Wellenlängen 334 nm, 366 nm und 436 nm bestimmt. Die Quantenausbeute für Photobleichung von Carminsäure in Liquid Red Colour in Fruchtwein (pH 3,1 mit 15%, v/v, Ethanol) war 2,1·10^–2 Mol·Einstein^–1 bei 334 nm; 1,3·10^–3 Mol·Einstein^–1 bei 366 nm und 5,6·10^–5 Mol·Einstein^–1 bei 436 nm. Die Quantenausbeute für Hexacol Sunset Yellow FCF Supra in Fruchtwein war 5,9·10^–4 Mol·Einstein^–1 bei 334 nm und 2,4·10^–4 Mol·Einstein^–1 bei 366 nm. Die Quantenausbeute für Photobleichung für Hexacol Red 2G Supra war 3,7·10^–5 Mol·Einstein^–1 bei 366 nm Bestrahlung. Für Hexacol Red 2G Supra und Hexacol Sunset Yellow FCF Supra war die Quantenausbeute bei 436 nm Bestrahlung geringer als 10^–6 Mol·Einstein^–1, das gleiche gilt für Hexacol Red 2G Supra bei 334 nm Bestrahlung. Folgende Reihenfolge der Lichtempfindlichkeit in Fruchtwein wurde festgestellt (bei 366 nm): Liquid Red Colour > Hexacol Sunset Yellow FCF Supra > Hexacol Red 2G Supra. Caramel Farbe in Aquavit (pH 7,1, mit 42%, v/v, Ethanol) war mäßig lichtempfindlich; die Quantenausbeute war fast unabhängig von der Bestrahlungswellenlänge. Relative Quantenausbeuten von 1,6 bei 334 nm, 1,0 bei 366 nm und 1,0 bei 436 nm wurden bestimmt. Der letzte Wert entspricht 2,6 g Caramel per Einstein.

     

Imaging the Molecular Motions of Autonomous Repair in a Self‐Healing Polymer

Self‐healing polymers can significantly extend the service life of materials and structures by autonomously repairing damage. Intrinsic healing holds great promise as a design strategy to mitigate the risks of damage by delaying or preventing catastrophic failure. However, experimentally resolving the microscopic mechanisms of intrinsic repair has proven highly challenging. This work demonstrates how optical micromechanical mapping enables the quantitative imaging of these molecular‐scale dynamics with high spatiotemporal resolution. This approach allows disentangling delocalized viscoplastic relaxation and localized cohesion‐restoring rebonding processes that occur simultaneously upon damage to a self‐healing polymer. Moreover, frequency‐ and temperature‐dependent imaging provides a way to pinpoint the repair modes in the relaxation spectrum of the quiescent material. These results give rise to a complete picture of autonomous repair that will guide the rational design of improved self‐healing materials.     

Water characteristics in cooked beef as influenced by ageing and high-pressure treatment-an NMR micro imaging study

The water characteristics in cooked pressure-heat treated (45?°C for 45 min prior to pressurisation at 150 MPa for 30 min) and non-pressurised, cooked (control) samples of beef Longissimus aged for 1, 3, 8 or 16 days were studied by nuclear magnetic resonance microscopy. A multi-echo sequence was used to obtain T2 images, and independent of ageing period, the T2 values were found to be lower in pressure-heat treated meat revealing alterations in water characteristics of pressure-treated, cooked meat compared with cooked meat. With increasing ageing duration, the T2 values in both pressure-treated, cooked and cooked meat decreased indicating that the water became more tightly trapped in the protein network. In addition, independent of length of ageing period the relationship between cooking loss in the cooked meat and transverse relaxation differed between non-pressurised and pressure-treated meat, which reveals that the mechanisms changing the water properties in beef during ageing are different from those occuring during pressure-heat treatment of meat.     

Functional Screen for microRNAs Suppressing Anchorage-Independent Growth in Human Cervical Cancer Cells

The progression of anchorage-dependent epithelial cells to anchorage-independent growth represents a critical hallmark of malignant transformation. Using an in vitro model of human papillomavirus (HPV)-induced transformation, we previously showed that acquisition of anchorage-independent growth is associated with marked (epi)genetic changes, including altered expression of microRNAs. However, the laborious nature of the conventional growth method in soft agar to measure this phenotype hampers a high-throughput analysis. We developed alternative functional screening methods using 96- and 384-well ultra-low attachment plates to systematically investigate microRNAs regulating anchorage-independent growth. SiHa cervical cancer cells were transfected with a microRNA mimic library (n = 2019) and evaluated for cell viability. We identified 84 microRNAs that consistently suppressed growth in three independent experiments. Further validation in three cell lines and comparison of growth in adherent and ultra-low attachment plates yielded 40 microRNAs that specifically reduced anchorage-independent growth. In conclusion, ultra-low attachment plates are a promising alternative for soft-agar assays to study anchorage-independent growth and are suitable for high-throughput functional screening. Anchorage independence suppressing microRNAs identified through our screen were successfully validated in three cell lines. These microRNAs may provide specific biomarkers for detecting and treating HPV-induced precancerous lesions progressing to invasive cancer, the most critical stage during cervical cancer development.     

Glucosinolate Content and Sensory Evaluation of Baby Leaf Rapeseed from Annual and Biennial White‐ and Yellow‐Flowering Cultivars with Repeated Harvesting in Two Seasons

The chemical and sensory quality of field‐grown vegetables may be influenced by cultivar choice and agronomic factors but knowledge is lacking on the new rapeseed vegetables. White‐ and yellow‐flowering rapeseed cultivars were tested in two seasonally different field studies in Denmark at three different growing stages by early sowing the first year and late sowing the second year. Content of glucosinolates (GLSs) was analyzed, and the sensory quality of baby leaf samples was evaluated. The GLS content differed among cultivars across years in all growing stages, with biennial cultivars having the highest GLS content. In the second year, a higher content of all identified GLSs was found at two growing stages except for neoglucobrassicin and gluconasturtiin, compared to the first year. On the contrary, higher contents of all identified GLSs were found at a third stage in the first year except for progoitrin and 4‐methoxy glucobrassicin. Sensory evaluation of bitterness revealed differences among cultivars, higher intensities of bitterness in biennial cultivars, and a relationship between bitterness and content of bitter‐tasting and total GLSs. The effect of repeated harvesting on GLS content differed between the years and no general pattern was seen, except that the composition of individual GLSs was comparable for the biennial cultivars. We conclude that growing season and life cycle had a stronger influence on GLS content than stage at harvest. The link between bitter‐tasting GLSs and bitterness revealed that life cycle and seasonal effects affected the sensory profile of baby leaf rapeseed thereby making a healthier product due to high content of health‐beneficial GLSs.