Targeted deletions of complement lectin pathway genes improve outcome in traumatic brain injury, with MASP-2 playing a major role.

The lectin pathway (LP) of complement activation is believed to contribute to brain inflammation. The study aims to identify the key components of the LP contributing to TBI outcome as possible novel pharmacological targets. We compared the long-term neurological deficits and neuropathology of wild-type mice (WT) to that of mice carrying gene deletions of key LP components after experimental TBI. WT or MASP-2 (Masp2-/-), ficolin-A (Fcna-/-), CL-11 (Colec11-/-), MASP-1/3 (Masp1-/-), MBL-C (Mbl2-/-), MBL-A (Mbl1-/-) or MBL-/- (Mbl1-/-/Mbl2-/-) deficient male C57BL/6J mice were used. Mice underwent sham surgery or TBI by controlled cortical impact. The sensorimotor response was evaluated by neuroscore and beam walk tests weekly for 4 weeks. To obtain a comparative analysis of the functional outcome each transgenic line was rated according to a health score calculated on sensorimotor performance. For selected genotypes, brains were harvested 6 weeks after injury for histopathological analysis. MASP-2-/-, MBL-/- and FCN-A-/- mice had better outcome scores compared to WT. Of these, MASP-2-/- mice had the best recovery after TBI, showing reduced sensorimotor deficits (by 33% at 3 weeks and by 36% at 4 weeks). They also showed higher neuronal density in the lesioned cortex with a 31.5% increase compared to WT. Measurement of LP functional activity in plasma from MASP-2-/- mice revealed the absence of LP functional activity using a C4b deposition assay. The LP critically contributes to the post-traumatic inflammatory pathology following TBI with the highest degree of protection achieved through the absence of the LP key enzyme MASP-2, underlining a therapeutic utility of MASP-2 targeting in TBI

Targeted deletions of complement lectin pathway genes improve outcome in traumatic brain injury, with MASP-2 playing a major role.

The lectin pathway (LP) of complement activation is believed to contribute to brain inflammation. The study aims to identify the key components of the LP contributing to TBI outcome as possible novel pharmacological targets. We compared the long-term neurological deficits and neuropathology of wild-type mice (WT) to that of mice carrying gene deletions of key LP components after experimental TBI. WT or MASP-2 (Masp2-/-), ficolin-A (Fcna-/-), CL-11 (Colec11-/-), MASP-1/3 (Masp1-/-), MBL-C (Mbl2-/-), MBL-A (Mbl1-/-) or MBL-/- (Mbl1-/-/Mbl2-/-) deficient male C57BL/6J mice were used. Mice underwent sham surgery or TBI by controlled cortical impact. The sensorimotor response was evaluated by neuroscore and beam walk tests weekly for 4 weeks. To obtain a comparative analysis of the functional outcome each transgenic line was rated according to a health score calculated on sensorimotor performance. For selected genotypes, brains were harvested 6 weeks after injury for histopathological analysis. MASP-2-/-, MBL-/- and FCN-A-/- mice had better outcome scores compared to WT. Of these, MASP-2-/- mice had the best recovery after TBI, showing reduced sensorimotor deficits (by 33% at 3 weeks and by 36% at 4 weeks). They also showed higher neuronal density in the lesioned cortex with a 31.5% increase compared to WT. Measurement of LP functional activity in plasma from MASP-2-/- mice revealed the absence of LP functional activity using a C4b deposition assay. The LP critically contributes to the post-traumatic inflammatory pathology following TBI with the highest degree of protection achieved through the absence of the LP key enzyme MASP-2, underlining a therapeutic utility of MASP-2 targeting in TBI

Cross-analysis of the gene network controlling the homeostatic balance of carnosine and histidine-containing peptides in the CNS-PNS-pancreas-tissue triad of mice made hyperglycemic by streptozotocin challenge.

Programme and Abstracts of the 68th National Congress of the Italian Physiological Society (Società Italiana di Fisiologia) (Abstract) Allograft Inflammatory Factor1 (AIF1), alias ionized calcium-binding adapter molecule 1 (IBA1), is a highly conserved Ca2+-binding cytokine that has been identified as a key regulator of the immune response in vertebrates. AIF1 is highly expressed in activated macrophages during inflammatory responses, thus representing an accurate indicator of macrophage activation in the body and a pathogenic factor in several inflammatory diseases. Proteins of the AIF1 superfamily are also present in invertebrates, from sponges to echinoderms. Here, we describe the Paracentrotus lividus Aif-1, which encodes a predicted protein of 151 amino acids with high similarity to vertebrate AIF1. In the common sea urchin, molecular and immunocytochemical analyses showed the constitutive expression of Aif-1 in the coelomocytes. Aif-1 localizes in the perinuclear area of amoebocytes and inside the granules of red cells, but it is not present in vibratile cells and colorless spherula cells. Moreover, significant increase of P. lividus Aif-1 expression, at both mRNA and protein level, are observed in coelomocytes after Gram+ bacterial challenge. BLAST searches across Echinoderm databases resulted in identification of orthologous proteins from 24 species (8 sea urchins, 1 brittle star, 12 starfishes and 3 sea cucumbers). Among these, P. lividus Aif-1 shared a high identity with several species, e.g., 85.4% with the sea urchin Strongylocentrotus purpuratus, 60.9% with the brittle star Ophiocoma echinata, 59.6% with the starfish Achantaster planci, and 52.3% with the sea cucumber Apostichopus japonicus. Our study on P. lividus Aif-1 will contribute to elucidate AIF1 function along the evolutionary scale and to consolidate the key evolutionary position of echinoderms throughout metazoans with respect to the common immune paths

No overt deficits in aged tau-deficient C57Bl/6.Mapt^tm1(EGFP)kitGFP knockin mice

© 2016 van Hummel et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Several mouse lines with knockout of the tau-encoding MAPT gene have been reported in the past; they received recent attention due to reports that tau reduction prevented Aβ-induced deficits in mouse models of Alzheimer's disease. However, the effects of long-term depletion of tau in vivo remained controversial. Here, we used the tau-deficient GFP knockin line Mapttm1(EGFP)kiton a pure C57Bl/6 background and subjected a large cohort of males and females to a range of motor, memory and behavior tests and imaging analysis, at the advanced age of over 16 months. Neither heterozygous nor homozygous Mapttm1(EGFP)kitmice presented with deficits or abnormalities compared to wild-type littermates. Differences to reports using other tau knockout models may be due to different genetic backgrounds, respective gene targeting strategies or other confounding factors, such as nutrition. To this end, we report no functional or morphological deficits upon tau reduction or depletion in aged mice

No Overt Deficits in Aged Tau-Deficient C57Bl/6.Mapttm1(EGFP)Kit GFP Knockin Mice.

Several mouse lines with knockout of the tau-encoding MAPT gene have been reported in the past; they received recent attention due to reports that tau reduction prevented Aβ-induced deficits in mouse models of Alzheimer's disease. However, the effects of long-term depletion of tau in vivo remained controversial. Here, we used the tau-deficient GFP knockin line Mapttm1(EGFP)kit on a pure C57Bl/6 background and subjected a large cohort of males and females to a range of motor, memory and behavior tests and imaging analysis, at the advanced age of over 16 months. Neither heterozygous nor homozygous Mapttm1(EGFP)kit mice presented with deficits or abnormalities compared to wild-type littermates. Differences to reports using other tau knockout models may be due to different genetic backgrounds, respective gene targeting strategies or other confounding factors, such as nutrition. To this end, we report no functional or morphological deficits upon tau reduction or depletion in aged mice

Synthesis and Characterization of Novel Mono- And Bis-Guanyl Hydrazones as Potent and Selective ASIC1 Inhibitors Able to Reduce Brain Ischemic Insult

Acid-sensitive ion channels (ASICs) are sodium channels partially permeable to Ca2+ions, listed among putative targets in central nervous system (CNS) diseases in which a pH modification occurs. We targeted novel compounds able to modulate ASIC1 and to reduce the progression of ischemic brain injury. We rationally designed and synthesized several diminazene-inspired diaryl mono- and bis-guanyl hydrazones. A correlation between their predicted docking affinities for the acidic pocket (AcP site) in chicken ASIC1 and their inhibition of homo- and heteromeric hASIC1 channels in HEK-293 cells was found. Their activity on murine ASIC1a currents and their selectivity vs mASIC2a were assessed in engineered CHO-K1 cells, highlighting a limited isoform selectivity. Neuroprotective effects were confirmedin vitro, on primary rat cortical neurons exposed to oxygen-glucose deprivation followed by reoxygenation, andin vivo, in ischemic mice. Early lead 3b, showing a good selectivity for hASIC1 in human neurons, was neuroprotective against focal ischemia induced in mice

Normal body weight in aged <i>tau</i>^{<i>GFP/GFP</i>} mice.

<p>(A) Knockin strategy of <i>eGFP</i> into the <i>MAPT</i> locus of <i>tau</i>^{<i>GFP/GFP</i>} mice (adopted from Tucker et al. 2001). (B) Breeding strategy to obtain aged <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice. All genotypes were obtained at Mendelian distribution as indicated as % of total mice. (C) Genotyping of <i>MAPT</i> and <i>eGFP</i> in <i>tau</i>^{<i>GFP/GFP</i>} (–/–), <i>tau</i>^<i>+/GFP</i> (+/–) and <i>tau</i>^<i>+/+</i> (+/+) mice. (D) Western blotting of <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> brain extracts, showing reduction/loss of tau and expression of GFP in <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^{<i>GFP/GFP</i>} mice. (E) No significant differences in body weight between <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice or both genders at 16 months of age.</p

Absence of motor, memory and behavioral deficits in aged <i>tau</i>^{<i>GFP/GFP</i>} mice.

<p>Eight male and 12 female <i>tau</i>^{<i>GFP/GFP</i>} (–/–), 18 male and 20 female <i>tau</i>^<i>GFP/+</i> (+/–), and 12 male and 15 female <i>tau</i>^<i>+/+</i> (+/+) mice were tested, unless otherwise stated; (A) Similar latencies to fall on the accelerating Rota-Rod presented by <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice of both genders over 3 test days. (B) Comparable latency to fall off the inverted wire suggesting similar grip strength in <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice. (C) Examples of swim paths in the Morris water maze from <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice (small circle indicates position of submerged escape platform). Similar improvements in the latency to find the submerged platform in female and male <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice suggesting normal memory formation (1 female <i>tau</i>^{<i>GFP/GFP</i>}, 2 female <i>tau</i>^<i>+/GFP</i> and 4 female <i>tau</i>^<i>+/+</i> mice were excluded due to floating behavior). (D) Both, female and male <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice spent comparable times in the target quadrant during probe trials. (E) All mice found the marked platform similarly fast and average swim speed during MWM testing was comparable between genotypes, suggesting normal vision and swimming performance. (F) Examples of exploration paths of <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice in the open field arena during the first minute of 10 minute trials. Activity of all mice were comparable, as determined by distance travelled per minute. (G) No differences in time spent in the inner zone during OF testing of <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice. (H) During elevated plus maze testing, both female and male <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice predominantly spent time in the closed arms, with no differences between genotypes, suggesting no changes in anxiety/disinhibition.</p

No loss of substantia nigra neurons and synaptic proteins in aged <i>tau</i>^{<i>GFP/GFP</i>} mice.

<p>(A) Stereological assessment of serial coronal sections of <i>tau</i>^{<i>GFP/GFP</i>} (–/–), <i>tau</i>^<i>+/GFP</i> (+/–) and <i>tau</i>^<i>+/+</i> (+/+) brains stained with a tyrosine hydroxylase (TH)-specific antibody revealed indistinguishable numbers of dopaminergic SN neurons (n = 5/genotype). Representative stainings are shown. (B) Western blotting of brain extracts from cortex and hippocampus of 20 month-old <i>tau</i>^{<i>GFP/GFP</i>}, <i>tau</i>^<i>+/GFP</i> and <i>tau</i>^<i>+/+</i> mice showed no significant changes in levels of PSD-95, drebrin, NR1 and NR2B, and due to reduction of tau levels (and expression of GFP). Gapdh was probed to confirm equal loading. Quantification of blots was done from independent animals (n = 5; One-way ANOVA: **<i>P</i><0.01, ***<i>P</i><0.001, ****<i>P</i><0.0001; Student’s t-test: *<i>P</i><0.05 vs WT; ns, not significant (<i>P</i>-values provided)).</p

Short-term suppression of A315T mutant human TDP-43 expression improves functional deficits in a novel inducible transgenic mouse model of FTLD-TDP and ALS

The nuclear transactive response DNA-binding protein 43 (TDP-43) undergoes relocalization to the cytoplasm with formation of cytoplasmic deposits in neurons in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Pathogenic mutations in the TDP-43-encoding TARDBP gene in familial ALS as well as non-mutant human TDP-43 have been utilized to model FTD/ALS in cell culture and animals, including mice. Here, we report novel A315T mutant TDP-43 transgenic mice, iTDP-43, with controlled neuronal over-expression. Constitutive expression of human TDP-43 resulted in pronounced early-onset and progressive neurodegeneration, which was associated with compromised motor performance, spatial memory and disinhibition. Muscle atrophy resulted in reduced grip strength. Cortical degeneration presented with pronounced astrocyte activation. Using differential protein extraction from iTDP-43 brains, we found cytoplasmic localization, fragmentation, phosphorylation and ubiquitination and insolubility of TDP-43. Surprisingly, suppression of human TDP-43 expression in mice with overt neurodegeneration for only 1\ua0week was sufficient to significantly improve motor and behavioral deficits, and reduce astrogliosis. Our data suggest that functional deficits in iTDP-43 mice are at least in part a direct and transient effect of the presence of TDP-43. Furthermore, it illustrates the compensatory capacity of compromised neurons once transgenic TDP-43 is removed, with implications for future treatments