A hallmark of neurodegenerative proteinopathies is the formation of misfolded protein aggregates that cause cellular toxicity and contribute to cellular proteostatic collapse. Therapeutic options are currently being explored that target different steps in the production and processing of proteins implicated in neurodegenerative disease, including synthesis, chaperone-assisted folding and trafficking, and degradation via the proteasome and autophagy pathways. Other therapies, like mTOR inhibitors and activators of the heat shock response, can rebalance the entire proteostatic network. However, there are major challenges that impact the development of novel therapies, including incomplete knowledge of druggable disease targets and their mechanism of action as well as a lack of biomarkers to monitor disease progression and therapeutic response. A notable development is the creation of collaborative ecosystems that include patients, clinicians, basic and translational researchers, foundations and regulatory agencies to promote scientific rigor and clinical data to accelerate the development of therapies that prevent, reverse or delay the progression of neurodegenerative proteinopathies.

Background and Purpose-Activation of transcription factor nuclear factor-B (NF-B) may induce expression of either proinflammatory/apoptotic genes or antiapoptotic genes. Because a considerable number of middle cerebral artery occlusions (MCAOs) in humans are not associated with reperfusion during the first 24 hours, the role of NF-B after permanent MCAO (pMCAO) was investigated. Methods-Mice transgenic for a NF-B-driven ␤-globin reporter were exposed to pMCAO, and the expression of the reporter gene was quantified with real-time polymerase chain reaction. Mice lacking the p50 subunit of NF-B and wild-type controls were exposed to pMCAO with or without treatment with pyrrolidinedithiocarbamate (PDTC), an NF-B inhibitor. Brain sections of human stroke patients were immunostained for the activated NF-B. Results-pMCAO increased NF-B transcriptional activity to 260% (36.9Ϯ4.5 compared with 14.4Ϯ2.6; nϭ10; PϽ0.01) in the brain; this NF-B activation was completely blocked by PDTC (17.2Ϯ2.6; nϭ9; PϽ0.05). In p50 Ϫ/Ϫ mice, pMCAO resulted in 41% (18Ϯ3.2 mm 3 ; nϭ12) smaller infarcts compared with wild-type controls (32.9Ϯ3.8 mm 3 ; nϭ9; PϽ0.05), which was comparable to the protection achieved with PDTC in wild-type mice (19.6Ϯ4.2 mm 3 ; nϭ8). Pro-DTC, a PDTC analogue that does not cross the blood-brain barrier, had no effect, even though Pro-DTC and PDTC were equally protective in vitro. During the first 2 days of human stroke, NF-B was activated in neurons in the penumbral areas. Conclusions-NF-B is induced in neurons during

Temperature has a strong influence on the excitability and the contractility of the ectothermic heart that can be alleviated in some species by temperature acclimation. The molecular mechanisms involved in the temperature-induced improvement of cardiac contractility and excitability are, however, still poorly known. The present study examines the role of sarcolemmal K(+) currents from rainbow trout (Oncorhynchus mykiss) cardiac myocytes after thermal acclimation. The two major K(+) conductances of the rainbow trout cardiac myocytes were identified as the Ba(2+)-sensitive background inward rectifier current (I(K1)) and the E-4031-sensitive delayed rectifier current (I(Kr)). In atrial cells, the density of I(K1) is very low and the density of I(Kr) is remarkably high. The opposite is true for ventricular cells. Acclimation to cold (4 degrees C) modified the two K(+) currents in opposite ways. Acclimation to cold increases the density of I(Kr) and depresses the density of I(K1). These changes in repolarizing K(+) currents alter the shape of the action potential, which is much shorter in cold-acclimated than warm-acclimated (17 degrees C) trout. These results provide the first concrete evidence that K(+) channels of trout cardiac myocytes are adaptable units that provide means to regulate cardiac excitability and contractility as a function of temperature.

Pyrrolidine dithiocarbamate (PDTC) is an antioxidant and inhibitor of transcription factor nuclear factor kappa-B (NFjB). Because the role of NF-jB in brain injury is controversial and another NF-jB inhibiting thiocarbamate, DDTC, was recently shown to increase ischaemic brain damage, we investigated the effect of PDTC on transient brain ischaemia. Ischaemia was induced by occlusion of the middle cerebral artery (MCAO). In Wistar rats, the PDTC treatment started even 6 h after MCAO reduced the infarction volume by 48%. PDTC protected against MCAO also in spontaneously hypertensive rats and against forebrain ischaemia in Mongolian gerbils. PDTC prevented NF-jB activation in the ischaemic brain as determined by reduced DNA binding and nuclear translocation of NF-jB in neurons. PDTC had anti-inflammatory effect by preventing induction of NF-jB-regulated proinflammatory genes. In ischaemic rats, NF-jB was localized in cyclo-oxygenase-2-immunoreactive neurons. Blood cytokine levels were not altered by ischaemia or PDTC. When cultured neurons were exposed to an excitotoxin, no production of reactive oxygen species was detected, but PDTC provided protection and prevented nuclear translocation of NF-jB. The clinically approved PDTC and its analogues may act as antiinflammatories and may be safe therapies in stroke with a wide time window. Keywords: cytokines, inflammation, neuroimmunology, rodent. Stroke is the third leading cause of death in industrialized countries and a major cause of severe disability in the elderly (Centers for Disease Control 1992; Wolf et al. 1997). There is no other acute stroke therapy than intravenous thrombolysis and it is safe and effective only for a fraction of the patients (Bednar and Gross 1999;Lindsberg and Kaste 2003). Even though animal research conducted on acute ischaemic injury has revealed several pathophysiological cascades contributing to brain infarction, no breakthroughs in developing clinically relevant stroke therapy have been achieved. One factor is that laboratory studies on a single animal species or stroke model are not sufficient for modelling more variable human strokes (STAIR 1999). Another valid reason is that the compounds, which are protective in animal models, have a limited therapeutic time window or toxic secondary effects in humans (STAIR 1999).Reactive oxygen species (ROS) and inflammation are involved in human stroke and play a crucial role in animal models of stroke during the first days after the onset of ischaemia ( Abbreviations used: COX-2, cyclo-oxygenase-2; DDTC, diethyldithiocarbamate; div, days in vitro; FBS-HI, fetal bovine serum heat inactivated; IjB, inhibitor of NF-jB; IL-1b, interleukin-1b; iNOS, inducible nitric oxide synthase; LDH, lactate dehydrogenase; MAPKs, mitogen-activated protein kinases; MCA, middle cerebral artery; MCAO, middle cerebral artery occlusion; MEM, minimal essential medium; NF-jB, nuclear factor kappa-B; NMDA, N-methyl-D-asparatate; PDTC, pyrrolidine dithiocarbamate; ROS, reactive oxygen species; SHR, spontaneously ...

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In the traumatic brain injury (TBI) the initial impact causes both primary injury, and launches secondary injury cascades. One consequence, and a factor that may contribute to these secondary changes and functional outcome, is altered hemodynamics. The relative cerebral blood volume (CBV) changes in rat brain after severe controlled cortical impact injury were characterized to assess their interrelations with motor function impairment. Magnetic resonance imaging (MRI) was performed 1, 2, 4 h, and 1, 2, 3, 4, 7, and 14 days after TBI to quantify CBV and water diffusion. Neuroscore test was conducted before, and 2, 7, and 14 days after the TBI. We found distinct temporal profile of CBV in the perilesional area, hippocampus, and in the primary lesion. In all regions, the first response was drop of CBV. Perifocal CBV was reduced for over 4 days thereafter gradually recovering. After the initial drop, the hippocampal CBV was increased for 2 weeks. Neuroscore demonstrated severely impaired motor functions 2 days after injury (33% decrease), which then slowly recovered in 2 weeks. This recovery parallelled the recovery of perifocal CBV. CBV MRI can detect cerebrovascular pathophysiology after TBI in the vulnerable perilesional area, which seems to potentially associate with time course of sensory-motor deficit.

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