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Introduction: Sports-related concussion (SRC) is a common form of brain injury that lacks reliable methods to guide clinical decisions. MicroRNAs (miRNAs) can influence biological processes involved in SRC, and measurement of miRNAs in biological fluids may provide objective diagnostic and return to play/recovery biomarkers. Therefore, this prospective study investigated the temporal profile of circulating miRNA levels in concussed male and female athletes. Methods: Pre-season baseline blood samples were collected from amateur Australian rules football players (82 males, 45 females). Of these, 20 males and 8 females sustained an SRC during the subsequent season and underwent blood sampling at 2-, 6- and 13-days post-injury. A miRNA discovery Open Array was conducted on plasma to assess the expression of 754 known/validated miRNAs. miRNA target identified were further investigated with quantitative real-time PCR (qRT-PCR) in a validation study. Data pertaining to SRC symptoms, demographics, sporting history, education history and concussion history were also collected. Results: Discovery analysis identified 18 candidate miRNA. The consequent validation study found that plasma miR-221-3p levels were decreased at 6d and 13d, and that miR-27a-3p levels were decreased at 6d, when compared to baseline. Moreover, miR-27a and miR-221-3p levels were inversely correlated with SRC symptom severity. Conclusion: Circulating levels of miR-27a-3p and miR-221-3p were decreased in the sub-acute stages after SRC, and were inversely correlated with SRC symptom severity. Although further studies are required, these analyses have identified miRNA biomarker candidates of SRC severity and recovery that may one day assist in its clinical management. [ABSTRACT FROM AUTHOR]

Introduction: Sports-related concussion (SRC) is a common form of brain injury that lacks reliable methods to guide clinical decisions. MicroRNAs (miRNAs) can influence biological processes involved in SRC, and measurement of miRNAs in biological fluids may provide objective diagnostic and return to play/recovery biomarkers. Therefore, this prospective study investigated the temporal profile of circulating miRNA levels in concussed male and female athletes. Methods: Pre-season baseline blood samples were collected from amateur Australian rules football players (82 males, 45 females). Of these, 20 males and 8 females sustained an SRC during the subsequent season and underwent blood sampling at 2-, 6- and 13-days postinjury. A miRNA discovery Open Array was conducted on plasma to assess the expression of 754 known/validated miRNAs. miRNA target identified were further investigated with quantitative real-time PCR (qRT-PCR) in a validation study. Data pertaining to SRC symptoms, demographics, sporting history, education history and concussion history were also collected. Results: Discovery analysis identified 18 candidate miRNA. The consequent validation study found that plasma miR-221-3p levels were decreased at 6d and 13d, and that miR-27a-3p levels were decreased at 6d, when compared to baseline. Moreover, miR-27a and miR-221-3p levels were inversely correlated with SRC symptom severity. Conclusion: Circulating levels of miR-27a-3p and miR-221-3p were decreased in the sub-acute stages after SRC, and were inversely correlated with SRC symptom severity. Although further studies are required, these analyses have identified miRNA biomarker candidates of SRC severity and recovery that may one day assist in its clinical management. [ABSTRACT FROM AUTHOR]

The anti-inflammatory peptide annexin-1 binds to formyl peptide receptors (FPR) but little is known about its mechanism of action in the vasculature. Here we investigate the effect of annexin peptide Ac2-26 on NADPH oxidase activity induced by tumour necrosis factor alpha (TNFα) in human endothelial cells. Superoxide release and intracellular reactive oxygen species (ROS) production from NADPH oxidase was measured with lucigenin-enhanced chemiluminescence and 2′,7′-dichlorodihydrofluorescein diacetate, respectively. Expression of NADPH oxidase subunits and intracellular cell adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) were determined by real-time PCR and Western blot analysis. Promoter activity of nuclear factor kappa B (NFκB) was measured by luciferase activity assay. TNFα stimulated NADPH-dependent superoxide release, total ROS formation and expression of ICAM-1and VCAM-1. Pre-treatment with N-terminal peptide of annexin-1 (Ac2-26, 0.5–1.5 µM) reduced all these effects, and the inhibition was blocked by the FPRL-1 antagonist WRW4. Furthermore, TNFα-induced NFκB promoter activity was attenuated by both Ac2-26 and NADPH oxidase inhibitor diphenyliodonium (DPI). Surprisingly, Nox4 gene expression was reduced by TNFα whilst expression of Nox2, p22phox and p67phox remained unchanged. Inhibition of NADPH oxidase activity by either dominant negative Rac1 (N17Rac1) or DPI significantly attenuated TNFα-induced ICAM-1and VCAM-1 expression. Ac2-26 failed to suppress further TNFα-induced expression of ICAM-1 and VCAM-1 in N17Rac1-transfected cells. Thus, Ac2-26 peptide inhibits TNFα-activated, Rac1-dependent NADPH oxidase derived ROS formation, attenuates NFκB pathways and ICAM-1 and VCAM-1 expression in endothelial cells. This suggests that Ac2-26 peptide blocks NADPH oxidase activity and has anti-inflammatory properties in the vasculature which contributes to modulate in reperfusion injury inflammation and vascular disease. [ABSTRACT FROM AUTHOR]

NADPH oxidases contribute to brain injury, yet they may also have a role in brain repair, particularly in vascular signaling and angiogenesis. This study determined the temporal and spatial profile of NADPH oxidase subunit expression/activity concurrently with angiogenesis in the brain following transient ischemic stroke induced by prolonged constriction of the middle cerebral artery by perivascular injection of endothelin-1 in conscious Hooded Wistar rats (n = 47). VEGF mRNA expression was increased in the ipsilateral cortex and striatum between 6 h and 28 days post-stroke concurrently with a marked increase in Nox2 mRNA expression up to 7 days, and increased Nox4 mRNA expression detected between 7 and 28 days. Point counting of blood vessels using Metamorph imaging software showed increased vascular sprouting between 3 and 7 days after stroke with new vascular networks detected in the core infarct region by 14 days. Angiogenic blood vessels 3 and 7 days post-stroke were observed to co-localise with both Nox2 antibody and dihydroethidium fluorescence suggesting a role for Nox2 generated superoxide during the phase of vascular remodeling, whilst Nox4 expression was detected once new cerebral vessels had formed. These results indicate for the first time that ROS signaling through a cerebrovascular Nox2 NADPH oxidase may be important in initiating brain angiogenesis. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small noncoding RNAs that act as regulators of gene expression by targeting mature messenger RNAs. Following the initial report of the presence of miRNAs in serum and plasma a number of studies have successfully demonstrated the use of these miRNAs as biomarkers of disease. Currently, there are many methods of isolating total RNA from liquid samples. Here, we describe a simple, cost effective method for extraction of RNA from human serum as well as subsequent real time PCR analysis of miRNA levels. [ABSTRACT FROM AUTHOR]

Fluid secretion across the blood–brain barrier, critical for maintaining the correct fluid balance in the brain, entails net secretion of HCO3−, which is brought about by the combined activities of ion transporters situated in brain microvessels. These same transporters will concomitantly influence intracellular pH (pHi). To analyse the transporters that may be involved in the maintenance of pHi and hence secretion of HCO3−, we have loaded primary cultured endothelial cells derived from rat brain microvessels with the pH indicator BCECF and suspended them in standard NaCl solutions buffered with Hepes or Hepes plus 5% CO2/HCO3−. pHi in the standard solutions showed a slow acidification over at least 30 min, the rate being less in the presence of HCO3− than in its absence. However, after accounting for the difference in buffering, the net rates of acid loading with and without HCO3− were similar. In the nominal absence of HCO3− the rate of acid loading was increased equally by removal of external Na+ or by inhibition of Na+/H+ exchange by ethylisopropylamiloride (EIPA). By contrast, in the presence of HCO3− the increase in the rate of acid loading when Na+ was removed was much larger and the rate was then also significantly greater than the rate observed in the absence of both Na+ and HCO3−. Removal of Cl− in the presence of HCO3− produced an alkalinization followed by a resumption of the slow acid gain. Removal of Na+ following removal of Cl− increased the rate of acid gain. In the presence of HCO3− and initial presence of Na+ and Cl−, DIDS inhibited the changes in pHi produced by removal of either Na+ or Cl−. These are the expected results if these cells possess an AE-like Cl−/HCO3− exchanger, a ‘channel-like’ permeability allowing slow influx of acid (or efflux of HCO3−), a NBC-like Cl−-independent Na+−HCO3− cotransporter, and a NHE-like Na+/H+ exchanger. The in vitro rates of HCO3− loading via the Na+−HCO3− cotransporter could, if the transporter is located on the apical, blood-facing side of the cells, account for the net secretion of HCO3− into the brain. [ABSTRACT FROM AUTHOR]

Himalayan glaciers have shrunk rapidly in recent years, but provide a vital water resource for those living in their densely populated downstream catchments. Many of these glaciers are debris-covered, which strongly influences their response to climate change. Surface melt ponds are characteristic of debris-covered glaciers and can greatly enhance local melt rates. Furthermore, surface ponds can grow rapidly in size and coalesce to form large lakes. The growth of these glacial ponds and lakes represents a major hazard in the form of outburst floods, which can cause catastrophic damage downstream. Here, we use high-resolution (10 m) Sentinel-2A satellite imagery to quantify the spatiotemporal changes of 6,425 supraglacial ponds for 10 glaciers in Everest region of Nepal. Our analysis spans the period 2015-2018 and represents the most up-to-date study of ice surface ponds in the region. All 10 glaciers displayed an overall increase in ponded area over the study period, however year to year variation and glacier to glacier variation was observed. On the three larger glaciers (Ngozumpa, Pangbung and Khumbu) pond number reduced over the period, suggesting coalescence, whilst on the smaller glaciers pond number increased, suggesting ponded area is growing via new pond formation. Both Imja and Spillway Lake expanded over the period, and Khumbu Glacier continued to develop a chain of connected ponds, indicative of large lake development. Ice cliffs were found on all 10 glaciers, and a higher percentage of ponds had an adjacent cliff than didn't (54%), however cliffs were found to have little impact on pond growth, with more pond forming without a cliff during the study. Ponds were found to form irrespective of the surface slope, but favored locations of lower surface velocity (e.g. the terminus). Our data demonstrate that high-resolution imagery (<10m) is required to prevent omissions of smaller ponds, which account for 28-59% of the total number of ponds identified here. Finally, we classify the proglacial lakes in our study regions according to stage of glacial lake development (Komori et al., 2008; Robertson et al., 2012). We find that two lakes transitioned between stages during out study period, which indicates that lakes in the region are evolving rapidly. Furthermore, we find that some of the study lakes display characteristics of multiple classes in previous classification systems, so we propose an adapted classification system. Overall, our results demonstrate a continued trend of pond expansion, and thus heightened risk of outburst floods in the coming decades in the Everest Region, and should continue to be monitored closely to support regional hazard assessments. Key Words: Supraglacial Ponds, Debris, Ice-cliffs, Sentinel-2A, Outburst floods, Hazards. [ABSTRACT FROM AUTHOR]

Objectives: There is evidence that treatment with nerve growth factor (NGF) may reduce neuroinflammation and apoptosis after a traumatic brain injury (TBI). NGF is thought to exert its effects via binding to either TrkA or p75 neurotrophin receptors. This study aimed to investigate the effects of a selective TrkA agonist, gambogic amide (GA), on TBI pathology and outcomes in mice following lateral fluid percussion injury. Methods: Male C57BL/6 mice were given either a TBI or sham injury, and then received subcutaneous injections of either 2 mg/kg of GA or vehicle at 1, 24, and 48 h post-injury. Following behavioural studies, mice were euthanized at 72 h post-injury for analysis of neuroinflammatory, apoptotic, and neurite outgrowth markers. Results: Behavioural testing revealed that GA did not mitigate motor deficits after TBI. TBI caused an increase in cortical and hippocampal expression of several markers of neuroinflammation and apoptosis compared to sham groups. GA treatment did not attenuate these increases in expression, possibly contributed to by our finding of TrkA receptor down-regulation post-TBI. Conclusions: These findings suggest that GA treatment may not be suitable for attenuating TBI pathology and improving outcomes. [ABSTRACT FROM AUTHOR]

Fucoidan is a sulfated polysaccharide found in a range of brown algae species. Growing evidence supports the long‐term supplementation of fucoidan as an ergogenic aid to improve skeletal muscle performance. The aim of this study was to investigate the effect of fucoidan on the skeletal muscle of mice. Male BL/6 mice (N = 8–10) were administered a novel fucoidan blend (FUC, 400 mg/kg/day) or vehicle (CON) for 4 weeks. Treatment and control experimental groups were further separated into exercise (CON+EX, FUC+EX) or no‐exercise (CON, FUC) groups, where exercised groups performed 30 min of treadmill training three times per week. At the completion of the 4‐week treatment period, there was a significant increase in cross‐sectional area (CSA) of muscle fibers in fucoidan‐treated extensor digitorum longus (EDL) and soleus fibers, which was accompanied by a significant increase in tibialis anterior (TA) muscle force production in fucoidan‐treated groups. There were no significant changes in grip strength or treadmill time to fatigue, nor was there an effect of fucoidan or exercise on mass of TA, EDL, or soleus muscles. In gastrocnemius muscles, there was no change in mRNA expression of mitochondrial biogenesis markers PGC‐1α and Nrf‐2 in any experimental groups; however, there was a significant effect of fucoidan supplementation on myosin heavy chain (MHC)‐2x, but not MHC‐2a, mRNA expression. Overall, fucoidan increased muscle size and strength after 4 weeks of supplementation in both exercised and no‐exercised mice suggesting an important influence of fucoidan on skeletal muscle physiology. [ABSTRACT FROM AUTHOR]

Abstract: The effects of in vitro preconditioning protocols on the ultimate survival of myoblasts implanted in an in vivo tissue engineering chamber were examined. In vitro testing: L6 myoblasts were preconditioned by heat (42 °C; 1.5 h); hypoxia (<8% O2; 1.5 h); or nitric oxide donors: S-nitroso-N-acetylpenicillamine (SNAP, 200 μM, 1.5 h) or 1-[N-(2-aminoethyl)-N-(2-aminoethyl)amino]-diazen-1-ium-1,2-diolate (DETA-NONOate, 500 μM, 7 h). Following a rest phase preconditioned cells were exposed to 24 h hypoxia, and demonstrated minimal overall cell loss, whilst controls (not preconditioned, but exposed to 24 h hypoxia) demonstrated a 44% cell loss. Phosphoimmunoblot analysis of pro-survival signaling pathways revealed significant activation of serine threonine kinase Akt with DETA-NONOate (p < 0.01) and heat preconditioning (p < 0.05). DETA-NONOate also activated ERK 1/2 signaling (p < 0.05). In vivo implantation: 100,000 preconditioned (heat, hypoxia, or DETA-NONOate) myoblasts were implanted in SCID mouse tissue engineering chambers. 100,000 (not preconditioned) myoblasts were implanted in control chambers. At 3 weeks, morphometric assessment of surviving myoblasts indicated myoblast percent volume (p = 0.012) and myoblasts/mm2 (p = 0.0005) overall significantly increased in preconditioned myoblast chambers compared to control, with DETA-NONOate-preconditioned myoblasts demonstrating the greatest increase in survival (p = 0.007 and p = 0.001 respectively). DETA-NONOate therefore has potential therapeutic benefits to significantly improve survival of transplanted cells. [Copyright &y& Elsevier]

Abstract: Cardiac fibrosis is a consequence of many cardiovascular diseases and contributes to impaired ventricular function. Activation of the prostacyclin receptor (IP) protects against cardiac fibrosis, but the molecular mechanisms are not totally understood. Using mouse cardiac fibroblasts, we found that IP activation with cicaprost suppressed expression of collagen I and other target genes of transforming growth factor-β. This effect of cicaprost was unlikely to be mediated by inhibition of the Smad2/3 or mitogen-activated protein kinase (MAPK) activities, but was associated with cAMP elevation and phosphorylation of the transcription factor cAMP response element binding protein (CREB). Expression of a non-phosphorylated CREB mutant suppressed the inhibitory effect of cicaprost. It appears that phosphorylated CREB binds to and sequestrates the transcription coactivator CBP/p300 from binding to Smad. Inhibition of the intrinsic histone acetyl-transferase activity of CBP/p300 with garcinol significantly suppressed collagen I expression in fibroblasts. Using apolipoprotein E and IP double knockout mouse, we demonstrated that endogenous prostacyclin/IP signaling had an inhibitory effect on angiotensin II-induced cardiac fibrosis under hypercholesterolemic conditions. Taken together, our results suggest that the prostacyclin/IP pathway suppresses cardiac fibrosis, at least partly, by inducing CREB phosphorylation. [Copyright &y& Elsevier]