47 research outputs found
TLR7-mediated skin inflammation remotely triggers chemokine expression and leukocyte accumulation in the brain
Background:
The relationship between the brain and the immune system has become increasingly topical as, although it is immune-specialised, the CNS is not free from the influences of the immune system. Recent data indicate that peripheral immune stimulation can significantly affect the CNS. But the mechanisms underpinning this relationship remain unclear. The standard approach to understanding this relationship has relied on systemic immune activation using bacterial components, finding that immune mediators, such as cytokines, can have a significant effect on brain function and behaviour. More rarely have studies used disease models that are representative of human disorders.
Methods:
Here we use a well-characterised animal model of psoriasis-like skin inflammationâimiquimodâto investigate the effects of tissue-specific peripheral inflammation on the brain. We used full genome array, flow cytometry analysis of immune cell infiltration, doublecortin staining for neural precursor cells and a behavioural read-out exploiting natural burrowing behaviour.
Results:
We found that a number of genes are upregulated in the brain following treatment, amongst which is a subset of inflammatory chemokines (CCL3, CCL5, CCL9, CXCL10, CXCL13, CXCL16 and CCR5). Strikingly, this model induced the infiltration of a number of immune cell subsets into the brain parenchyma, including T cells, NK cells and myeloid cells, along with a reduction in neurogenesis and a suppression of burrowing activity.
Conclusions:
These findings demonstrate that cutaneous, peripheral immune stimulation is associated with significant leukocyte infiltration into the brain and suggest that chemokines may be amongst the key mediators driving this response
Intracerebroventricular injection of leukotriene B4 attenuates antigen-induced asthmatic response via BLT1 receptor stimulating HPA-axis in sensitized rats
Neuronal Chemokines: Versatile Messengers In Central Nervous System Cell Interaction
Whereas chemokines are well known for their ability to induce cell migration, only recently it became evident that chemokines also control a variety of other cell functions and are versatile messengers in the interaction between a diversity of cell types. In the central nervous system (CNS), chemokines are generally found under both physiological and pathological conditions. Whereas many reports describe chemokine expression in astrocytes and microglia and their role in the migration of leukocytes into the CNS, only few studies describe chemokine expression in neurons. Nevertheless, the expression of neuronal chemokines and the corresponding chemokine receptors in CNS cells under physiological and pathological conditions indicates that neuronal chemokines contribute to CNS cell interaction. In this study, we review recent studies describing neuronal chemokine expression and discuss potential roles of neuronal chemokines in neuronâastrocyte, neuronâmicroglia, and neuronâneuron interaction
TLR7-mediated skin inflammation remotely triggers chemokine expression and leukocyte accumulation in the brain
Effect of short term diet restriction on gene expression in the bovine hypothalamus using next generation RNA sequencing technology
Interaction de la chimiokine SDF-1a/CXCL12 avec le systĂšme vasopressinergique
La chimiokine SDF-1a (CXCL12) et son rĂ©cepteur CXCR4 co-localisent avec l hormone antidiurĂ©tique, l arginine vasopressine (AVP) dans l hypothalamus et la neurohypophyse. Au cours de nos Ă©tudes, nous avons Ă©tabli que : 1) le SDF-1a et l AVP prĂ©sentent une distribution cellulaire spĂ©cifique dans les neurones des noyaux magnocellulaires hypothalamiques et sont localisĂ©s dans les mĂȘmes vĂ©sicules neurosĂ©crĂ©toires de la neurohypophyse ; 2) le SDF-1a, par l intermĂ©diaire du CXCR4, module l activitĂ© Ă©lectrique du systĂšme Ă AVP et la libĂ©ration plasmatique d AVP; 3) l expression du couple SDF-1a/CXCR4 est rĂ©gulĂ©e lors de changements dans l Ă©quilibre hydrique suite Ă une dĂ©shydratation ou chez des animaux Brattleboro ; animaux dĂ©ficients en synthĂšse centrale d AVP. Les donnĂ©es originales obtenues au cours de ce travail ouvrent un axe de recherche novateur dans l implication des chimiokines dans la rĂ©gulation hydrique et plus gĂ©nĂ©ralement dans la rĂ©gulation des fonctions neuroendocriniennesThe chemokine SDF-1a (CXCL12) and its receptor CXCR4 are co-localized with the antidiuretic hormone arginine vasopressin (AVP) in the hypothalamus and in the posterior pituitary. During our studies we demonstrated that: 1) SDF-1a and AVP present a selective cellular distribution inside the neuronal cell and can be found in the same dense core vesicles in the nerve terminals in the posterior pituitary; 2) SDF-1a can modulate, through CXCR4, the electrical activity of AVP neurons and plasma AVP release; 3) the expression of SDF-1a/CXCR4 is regulated when the hydro-osmotic balance is disturbed as in case of dehydration or in Brattleboro rats ; an endogenous knock-out model for brain AVP deficiency. The original data obtained during this work open new avenues in the implication of chemokines in the water balance regulation and more generally in neuroendocrine functionsPARIS-BIUP (751062107) / SudocSudocFranceF
Spinal CCL2 pronociceptive action is no longer effective in CCR2 receptor antagonist-treated rats
Cellular and Subcellular Evidence for Neuronal Interaction between the Chemokine Stromal Cell-Derived Factor-1/CXCL 12 and Vasopressin: Regulation in the Hypothalamo-Neurohypophysial System of the Brattleboro Rats
Chemokines and chemokine receptors: New actors in neuroendocrine regulations
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