Impact of manganese on the hippocampus metabolism in the context of MEMRI: a proton HRMAS MRS study

Daoust, Alexia; Barbier, Emmanuel; Bohic, Sylvain; Stupar, Vasile; Maunoir-Regimbal, S.; Fauvelle, F.

doi:10.1039/c4tx00135d

Cited by 6 publications

(4 citation statements)

References 32 publications

(48 reference statements)

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“…This is consistent with our estimation that less than 0.01% of transcranially applied manganese reaches the brain, and that the average local concentrations of manganese in the ROIs in the brain rarely exceed 200 µM for the highest transcranially applied manganese concentration of 500 mM. Cellular studies indicate toxicity begins above the 200 µM manganese concentration in neural tissue (Daoust et al, 2015). …”

Section: Discussionsupporting

confidence: 90%

Transcranial manganese delivery for neuronal tract tracing using MEMRI

et al. 2017

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There has been a growing interest in the use of manganese-enhanced MRI (MEMRI) for neuronal tract tracing in mammals, especially in rodents. For this MEMRI application, manganese solutions are usually directly injected into specific brain regions. Recently it was reported that manganese ions can diffuse through intact rat skull. Here the local manganese concentrations in the brain tissue after transcranial manganese application were quantified and the effectiveness of tracing from the area under the skull where delivery occurred was determined. It was established that transcranially applied manganese yields brain tissue enhancement dependent on the location of application on the skull and that manganese that enters the brain transcranially can trace to deeper brain areas.

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Section: Discussionsupporting

confidence: 90%

Transcranial manganese delivery for neuronal tract tracing using MEMRI

et al. 2017

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“…Next, 80 nL of Mn 2+ solution (or vehicle) were instilled at a rate of 8 nL • min −1 via a connected Hamilton syringe. It has been reported that Mn 2+ is not toxic at this concentration . Ten minutes after the end of the injection, the cannula was retracted stepwise to avoid leakage of the tracer along the injection track.…”

Section: Methodsmentioning

confidence: 99%

Impact of tissue T₁on perfusion measurement with arterial spin labeling

et al. 2016

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A low dose of Mn reduces the tissue T without modifying CBF. Heterogeneous T impacts the ASL estimate of CBF in a region-dependent way. In animals, and when T modifications exceed the accuracy with which the tissue T can be determined, an estimate of tissue T should be obtained when quantifying CBF with an ASL technique. Magn Reson Med 77:1656-1664, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

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“…First, Mn 2+ dosing should be carefully optimized to minimize toxicity as well as ensure effective delivery to brain regions of interest. Several techniques for transporting Mn 2+ (typically in quantities of tens of nanomoles, corresponding to intracellular concentrations of 35–93 μM in the rodent brain) with minimum acute toxicity have already been established in the context of Mn 2+ enhanced MRI (MEMRI). These techniques include oral delivery, intraperitoneal administration, systemic injection, transcranial diffusion, and direct infusion in the cerebrospinal fluid. − Although Mn 2+ can passively enter the brain parenchyma, transient and reversible opening of the blood brain barrier (e.g., using focused ultrasound) may be employed to augment the amount of Mn 2+ transported .…”

Section: Discussionmentioning

confidence: 99%

A Protein-Based Biosensor for Detecting Calcium by Magnetic Resonance Imaging

et al. 2021

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Calcium-responsive contrast agents for magnetic resonance imaging (MRI) offer a promising approach for noninvasive brain-wide monitoring of neural activity at any arbitrary depth. Current examples of MRI-based calcium probes involve synthetic molecules and nanoparticles, which cannot be used to examine calcium signaling in a genetically encoded form. Here, we describe a new MRI sensor for calcium, based entirely on a naturally occurring calcium-binding protein known as calprotectin. Calciumbinding causes calprotectin to sequester manganese ions, thereby limiting Mn 2+ enhanced paramagnetic relaxation of nearby water molecules. We demonstrate that this mechanism allows calprotectin to alter T 1 and T 2 based MRI signals in response to biologically relevant calcium concentrations. The resulting response amplitude, i.e., change in relaxation time, is comparable to existing MRI-based calcium sensors as well as other reported protein-based MRI sensors. As a preliminary demonstration of its biological applicability, we used calprotectin to detect calcium in a lysed hippocampal cell preparation as well as in intact Chinese hamster ovary cells treated with a calcium ionophore. Calprotectin thus represents a promising path toward noninvasive imaging of calcium signaling by combining the molecular and cellular specificity of genetically encodable tools with the ability of MRI to image through scattering tissue of any size and depth.

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Impact of manganese on the hippocampus metabolism in the context of MEMRI: a proton HRMAS MRS study

Abstract: The HRMAS spectrum revealed an important impact of Mn 500 nmol on the hippocampal metabolism, not observed with Mn 8 nmol.

Cited by 6 publications

References 32 publications

Transcranial manganese delivery for neuronal tract tracing using MEMRI

Transcranial manganese delivery for neuronal tract tracing using MEMRI

Impact of tissue T₁on perfusion measurement with arterial spin labeling

A Protein-Based Biosensor for Detecting Calcium by Magnetic Resonance Imaging

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Impact of manganese on the hippocampus metabolism in the context of MEMRI: a proton HRMAS MRS study

Abstract: The HRMAS spectrum revealed an important impact of Mn 500 nmol on the hippocampal metabolism, not observed with Mn 8 nmol.

Cited by 6 publications

References 32 publications

Transcranial manganese delivery for neuronal tract tracing using MEMRI

Transcranial manganese delivery for neuronal tract tracing using MEMRI

Impact of tissue T1on perfusion measurement with arterial spin labeling

A Protein-Based Biosensor for Detecting Calcium by Magnetic Resonance Imaging

Contact Info

Product

Resources

About

Impact of tissue T₁on perfusion measurement with arterial spin labeling