Structural and functional brain changes in fibromyalgia: investigation of potential mechanisms associated with central sensitization in chronic pain

2010 ◽  
Vol 11 (4) ◽  
pp. S32 ◽  
Author(s):  
J. Craggs ◽  
M. Robinson ◽  
D. Price ◽  
W. Perlstein ◽  
R. Staud
Keyword(s):  
Chronic Pain ◽  
Central Sensitization ◽  
Functional Brain ◽  
Brain Changes

scholarly journals A38 TRPV1 VISCERAL AFFERENTS CONTROL CENTRAL SENSITIZATION IN IBD

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 278-279
Author(s):  
M Defaye ◽  
N Abdullah ◽  
M Iftinca ◽  
C Altier
Keyword(s):  
Chronic Pain ◽  
Central Sensitization ◽  
Microglial Activation ◽  
Visceral Pain ◽  
Purinergic Signaling ◽  
Designer Drugs ◽  
Visceral Afferents ◽  
Peripheral Sensitization ◽  
Specific Expression

Abstract Background Long-lasting changes in neural pain circuits precipitate the transition from acute to chronic pain in patients living with inflammatory bowel diseases (IBDs). While significant improvement in IBD therapy has been made to reduce inflammation, a large subset of patients continues to suffer throughout quiescent phases of the disease, suggesting a high level of plasticity in nociceptive circuits during acute phases. The establishment of chronic visceral pain results from neuroplasticity in nociceptors first, then along the entire neural axis, wherein microglia, the resident immune cells of the central nervous system, are critically involved. Our lab has shown that spinal microglia were key in controlling chronic pain state in IBD. Using the Dextran Sodium Sulfate (DSS) model of colitis, we found that microglial G-CSF was able to sensitize colonic nociceptors that express the pain receptor TRPV1. While TRPV1+ nociceptors have been implicated in peripheral sensitization, their contribution to central sensitization via microglia remains unknown. Aims To investigate the role of TRPV1+ visceral afferents in microglial activation and chronic visceral pain. Methods We generated DREADD (Designer Receptors Exclusively Activated by Designer Drugs) mice in which TRPV1 sensory neurons can be inhibited (TRPV1-hM4Di) or activated (TRPV1-hM3Dq) in a time and tissue specific manner using the inert ligand Clozapine-N-Oxide (CNO). To test the inhibition of TRPV1 neurons in DSS-induced colitis, TRPV1-hM4Di mice were treated with DSS 2.5% or water for 7 days and received vehicle or CNO i.p. injection twice daily. To activate TRPV1 visceral afferents, TRPV1-hM3Dq mice received vehicle or CNO daily for 7 days, by oral gavage. After 7 days of treatment, visceral pain was evaluated by colorectal distension and spinal cords tissues were harvested to measure microglial activation. Results Our data validated the nociceptor specific expression and function of the DREADD in TRPV1-Cre mice. Inhibition of TRPV1 visceral afferents in DSS TRPV1-hM4Di mice was able to prevent the colitis-induced microglial activation and thus reduce visceral hypersensitivity. In contrast, activation of TRPV1 visceral afferents in TRPV1-hM3Dq mice was sufficient to drive microglial activation in the absence of colitis. Analysis of the proalgesic mediators derived from activated TRPV1-hM3Dq neurons identified ATP as a key factor of microglial activation. Conclusions Overall, these data provide novel insights into the mechanistic understanding of the gut/brain axis in chronic visceral pain and suggest a role of purinergic signaling that could be harnessed for testing effective therapeutic approaches to relieve pain in IBD patients. Funding Agencies CCCACHRI (Alberta Children’s Hospital Research Institute) and CSM (Cumming School of Medicine) postdoctoral fellowship

Functional brain changes associated with cognitive trajectories determine specific tDCS‐induced effects among older adults

2021 ◽  
Author(s):  
Lídia Vaqué‐Alcázar ◽  
Kilian Abellaneda‐Pérez ◽  
Cristina Solé‐Padullés ◽  
Núria Bargalló ◽  
Cinta Valls‐Pedret ◽  
...  
Keyword(s):  
Older Adults ◽  
Functional Brain ◽  
Brain Changes

The Relationship Between Structural and Functional Brain Changes and Altered Emotion and Cognition in Chronic Low Back Pain Brain Changes

2018 ◽  
Vol 34 (3) ◽  
pp. 237-261 ◽  
Author(s):  
Sin Ki Ng ◽  
Donna M. Urquhart ◽  
Paul B. Fitzgerald ◽  
Flavia M. Cicuttini ◽  
Sultana M. Hussain ◽  
...  
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Chronic Low Back Pain ◽  
Low Back ◽  
Functional Brain ◽  
Brain Changes ◽  
The Relationship

Diffusion and functional MRI findings and their relationship to behaviour in postconcussion syndrome: a scoping review

2021 ◽  
pp. jnnp-2021-326604
Author(s):  
Melisa Gumus ◽  
Alexandra Santos ◽  
Maria Carmela Tartaglia
Keyword(s):  
Functional Mri ◽  
Scoping Review ◽  
Diffusion Tensor ◽  
Neuropsychiatric Symptoms ◽  
Postconcussion Syndrome ◽  
Mri Findings ◽  
Functional Brain ◽  
Behavioural Changes ◽  
Brain Changes ◽  
The Relationship

Postconcussion syndrome (PCS) is a term attributed to the constellation of symptoms that fail to recover after a concussion. PCS is associated with a variety of symptoms such as headaches, concentration deficits, fatigue, depression and anxiety that have an enormous impact on patients’ lives. There is currently no diagnostic biomarker for PCS. There have been attempts at identifying structural and functional brain changes in patients with PCS, using diffusion tensor imaging (DTI) and functional MRI (fMRI), respectively, and relate them to specific PCS symptoms. In this scoping review, we appraised, synthesised and summarised all empirical studies that (1) investigated structural or functional brain changes in PCS using DTI or fMRI, respectively, and (2) assessed behavioural alterations in patients with PCS. We performed a literature search in MEDLINE (Ovid), Embase (Ovid) and PsycINFO (Ovid) for primary research articles published up to February 2020. We identified 8306 articles and included 45 articles that investigated the relationship between DTI and fMRI parameters and behavioural changes in patients with PCS: 20 diffusion, 20 fMRI studies and 5 papers with both modalities. Most frequently studied structures were the corpus callosum, superior longitudinal fasciculus in diffusion and the dorsolateral prefrontal cortex and default mode network in the fMRI literature. Although some white matter and fMRI changes were correlated with cognitive or neuropsychiatric symptoms, there were no consistent, converging findings on the relationship between neuroimaging abnormalities and behavioural changes which could be largely due to the complex and heterogeneous presentation of PCS. Furthermore, the heterogeneity of symptoms in PCS may preclude discovery of one biomarker for all patients. Further research should take advantage of multimodal neuroimaging to better understand the brain–behaviour relationship, with a focus on individual differences rather than on group comparisons.

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