| 1. |
- Sellgren, C. M., et al.
(författare)
-
GRK3 deficiency elicits brain immune activation and psychosis
- 2021
-
Ingår i: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 26, s. 6820-6832
-
Tidskriftsartikel (refereegranskat)abstract
- The G protein-coupled receptor kinase (GRK) family member protein GRK3 has been linked to the pathophysiology of schizophrenia and bipolar disorder. Expression, as well as protein levels, of GRK3 are reduced in post-mortem prefrontal cortex of schizophrenia subjects. Here, we investigate functional behavior and neurotransmission related to immune activation and psychosis using mice lacking functional Grk3 and utilizing a variety of methods, including behavioral, biochemical, electrophysiological, molecular, and imaging methods. Compared to wildtype controls, the Grk3(-/-) mice show a number of aberrations linked to psychosis, including elevated brain levels of IL-1 beta, increased turnover of kynurenic acid (KYNA), hyper-responsiveness to D-amphetamine, elevated spontaneous firing of midbrain dopamine neurons, and disruption in prepulse inhibition. Analyzing human genetic data, we observe a link between psychotic features in bipolar disorder, decreased GRK expression, and increased concentration of CSF KYNA. Taken together, our data suggest that Grk3(-/-) mice show face and construct validity relating to the psychosis phenotype with glial activation and would be suitable for translational studies of novel immunomodulatory agents in psychotic disorders.
|
|
| 2. |
- Gracias, J., et al.
(författare)
-
Cerebrospinal fluid concentration of complement component 4A is increased in first episode schizophrenia
- 2022
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13:1
-
Tidskriftsartikel (refereegranskat)abstract
- Schizophrenia risk has been associated with the complement component 4 (C4) genes. Here the authors show that C4A is elevated in individuals with schizophrenia. Postsynaptic density is reduced in schizophrenia, and risk variants increasing complement component 4A (C4A) gene expression are linked to excessive synapse elimination. In two independent cohorts, we show that cerebrospinal fluid (CSF) C4A concentration is elevated in patients with first-episode psychosis (FEP) who develop schizophrenia (FEP-SCZ: median 0.41 fmol/ul [CI = 0.34-0.45], FEP-non-SCZ: median 0.29 fmol/ul [CI = 0.22-0.35], healthy controls: median 0.28 [CI = 0.24-0.33]). We show that the CSF elevation of C4A in FEP-SCZ exceeds what can be expected from genetic risk variance in the C4 locus, and in patient-derived cellular models we identify a mechanism dependent on the disease-associated cytokines interleukin (IL)-1beta and IL-6 to selectively increase neuronal C4A mRNA expression. In patient-derived CSF, we confirm that IL-1beta correlates with C4A controlled for genetically predicted C4A RNA expression (r = 0.39; CI: 0.01-0.68). These results suggest a role of C4A in early schizophrenia pathophysiology.
|
|
| 3. |
- Forsberg, A., et al.
(författare)
-
The Immune Response of the Human Brain to Abdominal Surgery
- 2017
-
Ingår i: Annals of Neurology. - : Wiley. - 0364-5134 .- 1531-8249. ; 81:4, s. 572-582
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Surgery launches a systemic inflammatory reaction that reaches the brain and associates with immune activation and cognitive decline. Although preclinical studies have in part described this systemic-to-brain signaling pathway, we lack information on how these changes appear in humans. This study examines the short-and long-term impact of abdominal surgery on the human brain immune system by positron emission tomography (PET) in relation to blood immune reactivity, plasma inflammatory biomarkers, and cognitive function. Methods: Eight males undergoing prostatectomy under general anesthesia were included. Prior to surgery (baseline), at postoperative days 3 to 4, and after 3 months, patients were examined using [C-11]PBR28 brain PET imaging to assess brain immune cell activation. Concurrently, systemic inflammatory biomarkers, ex vivo blood tests on immunoreactivity to lipopolysaccharide (LPS) stimulation, and cognitive function were assessed. Results: Patients showed a global downregulation of gray matter [C-11]PBR28 binding of 26 +/- 26% (mean +/- standard deviation) at 3 to 4 days postoperatively compared to baseline (p=0.023), recovering or even increasing after 3 months. LPS-induced release of the proinflammatory marker tumor necrosis factor-a in blood displayed a reduction (41 +/- 39%) on the 3rd to 4th postoperative day, corresponding to changes in [C-11]PBR28 distribution volume. Change in Stroop Color-Word Test performance between postoperative days 3 to 4 and 3 months correlated to change in [C-11]PBR28 binding (p=0.027). Interpretation: This study translates preclinical data on changes in the brain immune system after surgery to humans, and suggests an interplay between the human brain and the inflammatory response of the peripheral innate immune system. These findings may be related to postsurgical impairments of cognitive function.
|
|
