Deletion of the ageing gene p66Shc reduces early stroke size following ischaemia/reperfusion brain injury

Aims Stroke is a leading cause of morbidity and mortality, and its incidence increases with age. Both in animals and in humans, oxidative stress appears to play an important role in ischaemic stroke, with or without reperfusion. The adaptor protein p66Shc is a key regulator of reactive oxygen species (ROS) production and a mediator of ischaemia/reperfusion damage in ex vivo hearts. Hence, we hypothesized that p66Shc may be involved in ischaemia/reperfusion brain damage. To this end, we investigated whether genetic deletion of p66Shc protects from ischaemia/reperfusion brain injury. Methods and results Transient middle cerebral artery occlusion (MCAO) was performed to induce ischaemia/reperfusion brain injury in wild-type (Wt) and p66Shc knockout mice (p66Shc−/−), followed by 24 h of reperfusion. Cerebral blood flow and blood pressure measurements revealed comparable haemodynamics in both experimental groups. Neuronal nuclear antigen immunohistochemical staining showed a significantly reduced stroke size in p66Shc−/− when compared with Wt mice (P < 0.05, n = 7-8). In line with this, p66Shc−/− mice exhibited a less impaired neurological function and a decreased production of free radicals locally and systemically (P < 0.05, n = 4-5). Following MCAO, protein levels of gp91phox nicotinamide adenine dinucleotide phosphate oxidase subunit were increased in brain homogenates of Wt (P < 0.05, n = 4), but not of p66Shc−/− mice. Further, reperfusion injury in Wt mice induced p66Shc protein in the basilar and middle cerebral artery, but not in brain tissue, suggesting a predominant involvement of vascular p66Shc. Conclusion In the present study, we show that the deletion of the ageing gene p66Shc protects mice from ischaemia/reperfusion brain injury through a blunted production of free radicals. The ROS mediator p66Shc may represent a novel therapeutical target for the treatment of ischaemic strok

Nichtinvasive Zytokinbestimmung aus Fruchtwasser nach frühem vorzeitigen Blasensprung - Korrelation von Zytokinwerten und fetalen Parametern

Hintergrund: Ziel dieser Studie war es, einen Zusammenhang zwischen den Zytokinen Interleukin (IL)-6, IL-8 und Tumornekrosefaktor (TNF)-α aus nichtinvasiv gewonnenem Fruchtwasser nach frühem vorzeitigen Blasensprung (PPROM) mit definierten fetalen Parametern und dem neonatalen Outcome zu untersuchen. Grundlage dieser prospektiven klinisch-experimentellen Studie bildeten alle Schwangeren und deren Neugeborene der Klinik St. Hedwig in Regensburg, bei denen sich von Januar bis Dezember 2017 ein früher vorzeitiger Blasensprung in einem Schwangerschaftsalter von 23+0 SSW bis 33+6 SSW ereignete. Methoden: Das Fruchtwasser wurde nichtinvasiv aus dem Vaginalsekret der Schwangeren gewonnen. Zur Analyse des IL-6 wurden ein Enzyme-linked Immunosorbent Assay (ELISA) und ein Point-of-Care-Test (POCT) herangezogen und diese miteinander verglichen. IL-8 und TNF-α wurden mittels ELISA untersucht. Die Zytokine wurden zunächst im Hinblick auf das Schwangerschaftsalter bei PPROM und bei Geburt untersucht. Zur Beurteilung der fetalen Parameter wurden der Apgar-Score, das Geburtsgewicht, die IL-6 Werte aus dem Nabelschnurblut sowie der Nachweis pathogener Keime als Marker einer Infektion herangezogen. Outcome-Zielgrößen waren die neonatale Mortalität sowie das anhand erhöhter IL-6 Werte definierte fetale Inflammationssyndrom (FRIS). Weiterhin wurde das neonatale Outcome anhand der Kurzzeitmorbiditäten Atemnotsyndrom (RDS), Neugeborenen-Infektion und Neugeborenen-Sepsis untersucht. Ergebnisse: Die Zytokinkonzentrationen aus dem nichtinvasiv gewonnenen Fruchtwasser waren signifikant höher, je früher in der Schwangerschaft der vorzeitige Blasensprung stattgefunden hatte und je früher es in der Folge zur Entbindung kam. Zusätzlich wurde ein signifikanter Unterschied in der Höhe der IL-6 Konzentrationen bei Diagnose eines Amnioninfektionssyndroms festgestellt. Die mittels ELISA und POCT gemessenen Zytokinkonzentrationen korrelierten signifikant positiv miteinander, was eine Anwendung des POCT im klinischen Setting bei ausreichend vorhandenen und nicht verunreinigten Fruchtwasserproben zur Detektion maternaler Infektionen rechtfertigt. Der ELISA als geltender Goldstandard erbrachte signifikant höhere Konzentrationen als der POCT. Im Hinblick auf die neonatalen Parameter waren die Zytokinkonzentrationen umso höher, je niedriger der Apgar-Score sowie das Geburtsgewicht und je unreifer die Frühgeborenen waren. Weiterhin ergab die Studie, dass sich ein fetales Inflammationssyndrom mit erhöhten IL-6 Konzentrationen als Antwort auf eine intrauterine Entzündungsreaktion entwickelt und es infolge zu einem schlechteren neonatalen Outcome kommen kann. Bei Diagnose eines Atemnotsyndroms bzw. einer Neugeborenen-Sepsis zeigten sich in den jeweiligen Kohorten deutlich höhere IL-6, IL-8 und TNF-α Konzentrationen pränatal im Fruchtwasser als in den Kontrollgruppen

Towards remote monitoring of sub-seasonal glacier mass balance

This study presents a method that allows continuous monitoring of mass balance for remote or inaccessible glaciers, based on repeated oblique photography. Hourly to daily pictures from two automatic cameras overlooking two large valley glaciers in the Swiss Alps are available for eight ablation seasons (2004–11) in total. We determine the fraction of snow-covered glacier surface from orthorectified and georeferenced images and combine this information with simple accumulation and melt modelling using meteorological data. By applying this approach, the evolution of glacierwide mass balance throughout the ablation period can be directly calculated, based on terrestrial remote-sensing data. Validation against independent in situ mass-balance observations indicates good agreement. Our methodology has considerable potential for the remote determination of mountain glacier mass balance at high temporal resolution and could be applied using both repeated terrestrial and air-/spaceborne observations

Structural Modifications Yield Novel Insights Into the Intriguing Pharmacodynamic Potential of Anti-inflammatory Nitro-Fatty Acids

Endogenous nitro-fatty acids (NFA) are potent electrophilic lipid mediators that exert biological effects in vitro and in vivo via selective covalent modification of thiol-containing target proteins. The cytoprotective, anti-inflammatory, and anti-tumorigenic effects of NFA in animal models of disease caused by targeted protein nitroalkylation are a valuable basis for the development of future anti-phlogistic and anti-neoplastic drugs. Considering the complexity of diseases and accompanying comorbidities there is an urgent need for clinically effective multifunctional drugs. NFA are composed of a fatty acid backbone containing a nitroalkene moiety triggering Michael addition reactions. However, less is known about the target-specific structure–activity relationships and selectivities comparing different NFA targets. Therefore, we analyzed 15 NFA derivatives and compared them with the lead structure 9-nitro-oleic acid (9NOA) in terms of their effect on NF-κB (nuclear factor kappa B) signaling inhibition, induction of Nrf-2 (nuclear factor erythroid 2-related factor 2) gene expression, sEH (soluble epoxide hydrolase), LO (lipoxygenase), and COX-2 (cyclooxygenase-2) inhibition, and their cytotoxic effects on colorectal cancer cells. Minor modifications of the Michael acceptor position and variation of the chain length led to drugs showing increased target preference or enhanced multi-targeting, partly with higher potency than 9NOA. This study is a significant step forward to better understanding the biology of NFA and their enormous potential as scaffolds for designing future anti-inflammatory drugs

Deletion of the ageing gene p66Shc reduces early stroke size following ischaemia/reperfusion brain injury

Aims: Stroke is a leading cause of morbidity and mortality, and its incidence increases with age. Both in animals and in humans, oxidative stress appears to play an important role in ischaemic stroke, with or without reperfusion. The adaptor protein p66(Shc) is a key regulator of reactive oxygen species (ROS) production and a mediator of ischaemia/reperfusion damage in ex vivo hearts. Hence, we hypothesized that p66(Shc) may be involved in ischaemia/reperfusion brain damage. To this end, we investigated whether genetic deletion of p66(Shc) protects from ischaemia/reperfusion brain injury. Methods and results: Transient middle cerebral artery occlusion (MCAO) was performed to induce ischaemia/reperfusion brain injury in wild-type (Wt) and p66(Shc) knockout mice (p66(Shc-/-)), followed by 24 h of reperfusion. Cerebral blood flow and blood pressure measurements revealed comparable haemodynamics in both experimental groups. Neuronal nuclear antigen immunohistochemical staining showed a significantly reduced stroke size in p66(Shc-/-) when compared with Wt mice (P < 0.05, n = 7-8). In line with this, p66(Shc-/-) mice exhibited a less impaired neurological function and a decreased production of free radicals locally and systemically (P < 0.05, n = 4-5). Following MCAO, protein levels of gp91phox nicotinamide adenine dinucleotide phosphate oxidase subunit were increased in brain homogenates of Wt (P < 0.05, n = 4), but not of p66(Shc-/-) mice. Further, reperfusion injury in Wt mice induced p66(Shc) protein in the basilar and middle cerebral artery, but not in brain tissue, suggesting a predominant involvement of vascular p66(Shc). Conclusion: In the present study, we show that the deletion of the ageing gene p66(Shc) protects mice from ischaemia/reperfusion brain injury through a blunted production of free radicals. The ROS mediator p66(Shc) may represent a novel therapeutical target for the treatment of ischaemic stroke