Trehalose improves performance in the Morris water maze.

<p>Mice treated post-injury with trehalose revealed an overall significant performance improvement (two-way repeated measures ANOVA **<i>p</i> = 0.0048) in the learning (a) component of the Morris water maze. A <i>post hoc</i> Bonferroni’s multiple comparison test confirmed analysis showing significant performance of trehalose treated animals on day three (*<i>p</i> = 0.0200), day four (*<i>p</i> = 0.0197), day five (*<i>p</i> = 0.0038) and day 6 (*p = 0.0092). Trehalose treated mice also performed significantly better than SSV treated litter mates on the recall (b) component of the Morris water maze (*** <i>p</i> = 0.0010). Subsequent water maze with maltose treated and sham animals revealed no such significant improvement in the learning component of the trial. However, the recall component revealed a significantly better performance for the uninjured sham animals (ANOVA **<i>p</i> = 0.0019).</p

Copper is altered across the time course.

<p>Cu revealed ipsilateral significant increases at days 7 in ROI 1 (*<i>p</i><0.01), ROI 2 (*<i>p</i><0.01), and the entire hemisphere (*<i>p</i><0.01) for trehalose treated mice. Contralateral assessment revealed significant increases at days 7 in ROI 3 (*<i>p</i><0.01) and day 7 in the entire hemisphere (*<i>p</i><0.01).</p

Trehalose treatment improves y-maze performance in TBI mice.

<p>Trehalose treated mice showed a significant overall frequency of visitation preference for the novel arm (red) over the start arm (black) compared to SSV treated littermates at both one-minute (a) (**<i>p</i>< 0.001), and five-minute frequency (b) time points (*<i>p</i>< 0.01). Additionally, trehalose treated mice spent a significantly greater duration of time in the novel arm at the one-minute (c) (**<i>p</i>< 0.001) time point when compared to SSV controls. Subsequent y-maze revealed that maltose treated mice had no significant preference for the novel arm at both the one-minute (d) or five-minute (e) frequency measurements when compared to SSV treated littermates. Similarly, the one-minute duration measurement for maltose also revealed no significant increase in the duration time of visits when compared to SSV control littermates.</p

Representative LA-ICPMS schematic for iron, copper and zinc.

<p>a) Schematic demonstrating regions of interest selection for assessment of changes in metal levels radial to the site of impact overlaid the copper distribution of an unlesioned, untreated brain. b-d) Representative 28 day LA-ICP-MS images of the upper two quadrants of both hemsipheres for iron, copper and zinc. Selected ROIs were applied to each measured metal and extracted for statistical comparisons. Whole-hemisphere metal concentrations and equivalent ROIs on the contralateral side were also extracted. Images of sections were taken at approximately bregma +2.7 mm from 24 hours to 28 days post-lesion. All images have a lateral spatial resolution of 30 μm. Scale bar = 1 mm.</p

Trehalose increases synaptophysin, DCX, BDNF & Pro-BDNF in the contralateral cortex.

<p>Trehalose significantly increased synaptophysin protein in the contralateral cortex over SSV (*p<0.0221) and maltose (*p<0.0193) controls (a). Trehalose significantly increases DCX in the contralateral cortex compared to SSV (*p<0.0147) and maltose (*p<0.0123) controls (b). Trehalose also significantly increased BDNF protein in the contralateral cortex over SSV (*<i>p</i><0.0296) and maltose (*<i>p</i><0.0255) controls (c). Trehalose significantly increased Pro-BDNF protein in the contralateral cortex over SSV (*<i>p</i><0.0210) and maltose (*<i>p</i><0.0287) controls (d).</p

Iron is modulated across the time course.

<p>Fe was revealed to be significantly increased in the ipsilateral cortex in ROI1 at 7 days for trehalose treated mice (a) (*<i>p</i><0.01). The contralateral side revealed an increase at day 14 for trehalose treated mice in ROI1 (b) (*<i>p</i><0.01) and the entire hemisphere (h) (*<i>p</i><0.01). Ipsilateral Fe concentrations in every region surveyed were elevated regardless of treatment when compared to equivalent contralateral regions.</p

Additional file 1 of Alterations in iron content, iron-regulatory proteins and behaviour without tau pathology at one year following repetitive mild traumatic brain injury

Additional file 1: Figure S.1. Bulk metal analysis in mice receiving r-mTBI only. Figure S.2. Bulk metal analysis in mice receiving single mTBI only. Figure S.3. Swim speed of mice receiving a single or r-mTBI

Trehalose treated mice show significantly enhanced willingness to explore in the open field activity test.

<p>Post-TBI treated mice showed a significant reduction in anxiety and an increased willingness to explore when compared to SSV littermates. Post-treated mice showed a significant increase in ambulatory time (****<i>p</i>< 0.00001) (a), ambulatory distance (*<i>p</i>< 0.01) (b), vertical counts (*<i>p</i>< 0.01) (c) without a significant increase in velocity (d).</p

High-Resolution Elemental Bioimaging of Ca, Mn, Fe, Co, Cu, and Zn Employing LA-ICP-MS and Hydrogen Reaction Gas

Imaging of trace metal distribution in tissue sections by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is typically performed using spatial resolutions of 30 μm² and above. Higher resolution imaging is desirable for many biological applications in order to approach the dimensions of a single cell. The limiting factor for increasing resolution is sensitivity, where signal-to-noise ratios are poor due to inherent background spectral interferences and reduced sample volume with decreasing laser beam diameter. Several prominent spectral interferences are present for a number of biologically relevant isotopes, including the ⁴⁰Ar¹⁶O⁺ spectral interference on ⁵⁶Fe⁺. We examined if H₂ as a reaction gas could improve the analytical performance of imaging experiments for a range of masses with spectral interferences. At low (<1 mL min^–1) H₂ flow rates, greater spectral interference due to H⁺ adducts was observed for ⁵⁵Mn, ⁵⁷Fe, and ⁵⁹Co. At higher flow rates of up to 3 mL H₂ per minute, the spectral interferences were reduced leading to improvement in limits of analysis for masses with O- and N-based polyatomic interferences. Enhanced sensitivity with the reaction cell allowed construction of high resolution (6 μm²) imaging of ⁵⁶Fe in the mouse brain that approached the dimensions of single cells

Apparent ferroxidase activity derived from culture medium.

<p>Media of interest was tested by the triplex assay to measure loss of Fe²⁺ (<b>A</b>), conversion of Fe³⁺ (<b>B</b>) and loading of Fe³⁺ into TF (<b>C</b>). Without apo-TF, a one in five dilution of OptiMEM, neurobasal (NB) and RPMI-1640 (RPMI) media oxidized Fe²⁺ to Fe³⁺ (<b>A & B</b>). The addition of apo-TF (50 µM) promoted Fe²⁺ oxidation by all media (<b>A</b>), and had comparable ability to load Fe³⁺ onto TF (<b>C</b>). Assays were run at 26°C in HBS, pH = 7.2+ FAS (100 µM) ± apo-TF (50 µM). Individual data points were mean ± S.E. of 2 experiments, performed in duplicate.</p