Caroline Guglielmetti

Hôpital Beau-Séjour

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Annemie Van der Linden

University of Antwerp

Myriam M. Chaumeil

University of California, San Francisco

Marleen Verhoye

University of Antwerp

Peter Ponsaerts

University of Antwerp

Jelle Praet

Icometrix (Belgium)

Chloé Najac

Leiden University Medical Center

Jasmijn Daans

University of Antwerp

Lydia M. Le Page

University of Nebraska Medical Center

Zwi Berneman

Antwerp University Hospital

Ruth Vreys

Monash Medical Centre

Cooperative Institutions

University of California, San Francisco

University of Antwerp

University of California System

Neurological Surgery

KU Leuven

Harvard University

University of California, Berkeley

American Physical Therapy Association

Antwerp University Hospital

Laboratoire d’Imagerie Biomédicale

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Hyperpolarized ¹³C magnetic resonance spectroscopy detects toxin‐induced neuroinflammation in mice

NMR in Biomedicine (2019)

Lydia M. Le Page Caroline Guglielmetti Chloé Najac Brice Tiret Myriam M. Chaumeil

Lipopolysaccharide (LPS) is a commonly used agent for induction of neuroinflammation in preclinical studies. Upon injection, LPS causes activation of microglia and astrocytes, whose metabolism alters to favor glycolysis. Assessing in vivo neuroinflammation and its modulation following therapy remains challenging, and new noninvasive methods allowing for longitudinal monitoring would be highly valuable. Hyperpolarized (HP) 13 C magnetic resonance spectroscopy (MRS) is a promising technique for assessing in vivo metabolism. In addition to applications in oncology, the most commonly used probe of [1– 13 C] pyruvate has shown potential in assessing neuroinflammation‐linked metabolism in mouse models of multiple sclerosis and traumatic brain injury. Here, we aimed to investigate LPS‐induced neuroinflammatory changes using HP [1– 13 C] pyruvate and HP 13 C urea. 2D chemical shift imaging following simultaneous intravenous injection of HP [1– 13 C] pyruvate and HP 13 C urea was performed at baseline (day 0) and at days 3 and 7 post‐intracranial injection of LPS ( n = 6) or saline ( n = 5). Immunofluorescence (IF) analyses were performed for Iba1 (resting and activated microglia/macrophages), GFAP (resting and reactive astrocytes) and CD68 (activated microglia/macrophages). A significant increase in HP [1– 13 C] lactate production was observed at days 3 and 7 following injection, in the injected (ipsilateral) side of the LPS‐treated mouse brain, but not in either the contralateral side or saline‐injected animals. HP 13 C lactate/pyruvate ratio, without and with normalization to urea, was also significantly increased in the ipsilateral LPS‐injected brain at 7 days compared with baseline. IF analyses showed a significant increase in CD68 and GFAP staining at 3 days, followed by increased numbers of Iba1 and GFAP positive cells at 7 days post‐LPS injection. In conclusion, we can detect LPS‐induced changes in the mouse brain using HP 13 C MRS, in alignment with increased numbers of microglia/macrophages and astrocytes. This study demonstrates that HP 13 C spectroscopy has substantial potential for providing noninvasive information on neuroinflammation.

10.1002/nbm.4164

Cite

Citations (23)

Modulation of neuroinflammatory responses in the cuprizone mouse model following transplantation of mesenchymal stem cells genetically engineered to secrete IL13 coincides with the appearance of multiple alternatively activated macrophage and microglia phenotypes

Debbie Le Blon Caroline Guglielmetti Chloé Hoornaert Dearbhaile Dooley Jasmijn Daans

[Le Blon, D.; Hoornaert, C.; Daans, J.; De Vocht, N.; Reekmans, K.; Berneman, Z.; Ponsaerts, P.] Univ Antwerp, Lab Expt Hematol, B-2020 Antwerp, Belgium. [Le Blon, D.; Hoornaert, C.; Daans, J.; De Vocht, N.; Reekmans, K.; Hens, N.; Goossens, H.; Berneman, Z.; Ponsaerts, P.] Univ Antwerp, Vaccine & Infect Dis Inst, B-2020 Antwerp, Belgium. [Guglielmetti, C.; Verhoye, M.; Van der Linden, A.] Univ Antwerp, Bioimaging Lab, B-2020 Antwerp, Belgium. [Dooley, D.; Lemmens, E.; Hendrix, S.] Hasselt Univ, Biomed Res Inst, Dept Morphol, Diepenbeek, Belgium. [Santermans, E.; Hens, N.] Hasselt Univ, Ctr Stat, I Biostat, Hasselt, Belgium. [Hens, N.] Univ Antwerp, Chermid, B-2020 Antwerp, Belgium.

Source

Cite

Citations (0)

Long-term ovarian hormone deprivation alters functional connectivity, brain neurochemical profile and white matter integrity in the Tg2576 amyloid mouse model of Alzheimer's disease

Neurobiology of Aging (2021)

Firat Kara Michaël E. Belloy Rick Voncken Zahra Sarwari Garima Yadav

Neurochemical

10.1016/j.neurobiolaging.2021.02.011

Cite

Citations (13)

Monitoring Blood-Brain Barrier Integrity Following Amyloid-β Immunotherapy Using Gadolinium-Enhanced MRI in a PDAPP Mouse Model

Journal of Alzheimer s Disease (2016)

Ines Blockx Steve Einstein Pieter‐Jan Guns Johan Van Audekerke Caroline Guglielmetti

Background: Amyloid-related imaging abnormalities (ARIA) have been reported with some anti-amyloid-β (Aβ) immunotherapy trials. They are detected with magnetic resonance imaging (MRI) and thought to represent transient accumulation of fluid/edema (ARIA-E) or microhemorrhages (ARIA-H). Although the clinical significance and pathophysiology are unknown, it has been proposed that anti-Aβimmunotherapy may affect blood-brain barrier (BBB) integrity. Objective: To examine vascular integrity in aged (12–16 months) PDAPP and wild type mice (WT), we performed a series of longitudinal in vivo MRI studies. Methods: Mice were treated on a weekly basis using anti-Aβimmunotherapy (3D6) and follow up was done longitudinally from 1–12 weeks after treatment. BBB-integrity was assessed using both visual assessment of T1-weighted scans and repeated T1 mapping in combination with gadolinium (Gd-DOTA). Results: A subset of 3D6 treated PDAPP mice displayed numerous BBB disruptions, whereas WT and saline-treated PDAPP mice showed intact BBB integrity under the conditions tested. In addition, the contrast induced decrease in T1 value was observed in the meningeal and midline area. BBB disruption events occurred early during treatment (between 1 and 5 weeks), were transient, and resolved quickly. Finally, BBB-leakages associated with microhemorrhages were confirmed by Perls'Prussian blue histopathological analysis. Conclusion: Our preclinical findings support the hypothesis that 3D6 leads to transient leakage from amyloid-positive vessels. The current study has provided valuable insights on the time course of vascular alterations during immunization treatment and supports further research in relation to the nature of ARIA and the utility of in vivo repeated T1 MRI as a translational tool.

10.3233/jad-160023

Cite

Citations (17)

Validating visual evoked potentials as a preclinical, quantitative biomarker for remyelination efficacy

Brain (2022)

Christian Cordano Jung Hyung Sin Garrett Timmons Hao Yiu Karin J. Stebbins

Abstract Many biomarkers in clinical neuroscience lack pathological certification. This issue is potentially a significant contributor to the limited success of neuroprotective and neurorestorative therapies for human neurological disease—and is evident even in areas with therapeutic promise such as myelin repair. Despite the identification of promising remyelinating candidates, biologically validated methods to demonstrate therapeutic efficacy or provide robust preclinical evidence of remyelination in the CNS are lacking. Therapies with potential to remyelinate the CNS constitute one of the most promising and highly anticipated therapeutic developments in the pipeline to treat multiple sclerosis and other demyelinating diseases. The optic nerve has been proposed as an informative pathway to monitor remyelination in animals and human subjects. Recent clinical trials using visual evoked potential have had promising results, but without unequivocal evidence about the cellular and molecular basis for signal changes on visual evoked potential, the interpretation of these trials is constrained. The visual evoked potential was originally developed and used in the clinic as a diagnostic tool but its use as a quantitative method for assessing therapeutic response requires certification of its biological specificity. Here, using the tools of experimental pathology we demonstrate that quantitative measurements of myelination using both histopathological measures of nodal structure and ultrastructural assessments correspond to visual evoked potential latency in both inflammatory and chemical models of demyelination. Visual evoked potential latency improves after treatment with a tool remyelinating compound (clemastine), mirroring both quantitative and qualitative myelin assessment. Furthermore, clemastine does not improve visual evoked potential latency following demyelinating injury when administered to a transgenic animal incapable of forming new myelin. Therefore, using the capacity for therapeutic enhancement and biological loss of function we demonstrate conclusively that visual evoked potential measures myelin status and is thereby a validated tool for preclinical verification of remyelination.

Remyelination

10.1093/brain/awac207

Cite

Citations (40)

Different anesthesia regimes modulate the functional connectivity outcome in mice

Magnetic Resonance in Medicine (2014)

Elisabeth Jonckers Rafael Delgado y Palacios Disha Shah Caroline Guglielmetti Marleen Verhoye

Purpose The use of resting-state functional MRI (rsfMRI) in preclinical research is expanding progressively, with the majority of resting-state imaging performed in anesthetized animals. Since anesthesia may change the physiology and, in particular, the neuronal activity of an animal considerably, it may also affect rsfMRI findings. Therefore, this study compared rsfMRI data from awake mice with rsfMRI results obtained from mice anesthetized with α-chloralose (120 mg/kg), urethane (2.5 g/kg), or isoflurane (1%). Methods Functional connectivity (FC) was estimated using both independent component analysis (40 components) and ROI-based analysis to zoom in on the effect of different anesthetics on inter-hemispheric FC. Results The data revealed an important diminishment of cortical interhemispheric FC in both the α-chloralose and urethane groups in comparison with the isoflurane and awake groups. Conclusion When performing FC analysis in anesthetized mice, the impact of anesthetics must be taken into account. The required doses for stable anesthesia during MRI significantly decrease interhemispheric FC. Magn Reson Med 72:1103–1112, 2014. © 2013 Wiley Periodicals, Inc.

Chloralose

10.1002/mrm.25480

Cite

Citations (6)

Are subventricular zone endogenous neural stem cells responsible for the remyelination of the corpus callosum in the Cuprizone mouse model? An in-vivo bioluminescence and magnetic resonance imaging study

Caroline Guglielmetti Jelle Praet Ruth Vreys Janaki Raman Rangarajan Frederik Maes

Remyelination

Bioluminescence imaging

Source

Cite

Citations (0)

In vivo quantification of particle based and gene based MRI reporters in the rodent brain

Janaki Raman Rangarajan Greetje Vande Velde Caroline Guglielmetti Ruth Vreys Marleen Verhoye

Rodent model

Particle (ecology)

Source

Cite

Citations (0)

Detection of inflammatory cell function using 13C magnetic resonance spectroscopy of hyperpolarized [6-13C]-arginine

Scientific Reports (2016)

Chloé Najac Myriam M. Chaumeil Gary Kohanbash Caroline Guglielmetti Jeremy W. Gordon

Abstract Myeloid-derived suppressor cells (MDSCs) are highly prevalent inflammatory cells that play a key role in tumor development and are considered therapeutic targets. MDSCs promote tumor growth by blocking T-cell-mediated anti-tumoral immune response through depletion of arginine that is essential for T-cell proliferation. To deplete arginine, MDSCs express high levels of arginase, which catalyzes the breakdown of arginine into urea and ornithine. Here, we developed a new hyperpolarized 13 C probe, [6- 13 C]-arginine, to image arginase activity. We show that [6- 13 C]-arginine can be hyperpolarized and hyperpolarized [ 13 C]-urea production from [6- 13 C]-arginine is linearly correlated with arginase concentration in vitro . Furthermore we show that we can detect a statistically significant increase in hyperpolarized [ 13 C]-urea production in MDSCs when compared to control bone marrow cells. This increase was associated with an increase in intracellular arginase concentration detected using a spectrophotometric assay. Hyperpolarized [6- 13 C]-arginine could therefore serve to image tumoral MDSC function and more broadly M2-like macrophages.

10.1038/srep31397

Cite

Citations (29)

Enjeux cliniques et de santé publique de la consommation de crack

Revue Médicale Suisse (2025)

Tiphaine Robet Juliana Santos-Cruz Daniele Zullino Nadine De Carvalho Semedo Boris Baldo

Crack, the freebase form of cocaine, offers faster and more intense psychoactive effects due to its mode of administration by inhalation, while being of lower cost. These molecules act by blocking the reuptake of monoaminergic neurotransmitters, and their main effects stem from the rapid adrenergic response. The psychoactive effect is characterized by a marked surge of energy and social disinhibition. Crack consumption exacerbates the vulnerabilities of marginalized populations, requiring new approaches to address the social and health crises it generates. Since November 2024, a mobile team from HUG has deployed a street-based medical intervention, associated with intersectoral network work for a holistic and inclusive care approach.

10.53738/revmed.2025.21.904.226

Cite

Citations (0)