scholarly journals Metabolomic and lipidomic changes triggered by lipopolysaccharide-induced systemic inflammation in transgenic APdE9 mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Elena Puris ◽  
Štěpán Kouřil ◽  
Lukáš Najdekr ◽  
Sanna Loppi ◽  
Paula Korhonen ◽  
...  

AbstractPeripheral infections followed by systemic inflammation may contribute to the onset of Alzheimer`s disease (AD) and accelerate the disease progression later in life. Yet, the impact of systemic inflammation on the plasma and brain tissue metabolome and lipidome in AD has not been investigated. In this study, targeted metabolomic and untargeted lipidomic profiling experiments were performed on the plasma, cortices, and hippocampi of wild-type (WT) mice and transgenic APdE9 mice after chronic lipopolysaccharide (LPS) treatment, as well as saline-treated APdE9 mice. The lipidome and the metabolome of these mice were compared to saline-treated WT animals. In the brain tissue of all three models, the lipidome was more influenced than the metabolome. The LPS-treated APdE9 mice had the highest number of changes in brain metabolic pathways with significant alterations in levels of lysine, myo-inositol, spermine, phosphocreatine, acylcarnitines and diacylglycerols, which were not observed in the saline-treated APdE9 mice. In the WT mice, the effect of the LPS administration on metabolome and lipidome was negligible. The study provided exciting information about the biochemical perturbations due to LPS-induced inflammation in the transgenic AD model, which can significantly enhance our understanding of the role of systemic inflammation in AD pathogenesis.

2020 ◽  
Author(s):  
Bei Li ◽  
Meiling Chen ◽  
Adriano Aguzzi ◽  
Caihong Zhu

AbstractThe progression of prion diseases is accompanied by the accumulation of prions in the brain. Ablation of microglia enhances prion accumulation and accelerates disease progression, suggesting that microglia play a neuroprotective role by clearing prions. However, the mechanisms underlying the phagocytosis and clearance of prion are largely unknown. The macrophage scavenger receptor 1 (Msr1) is an important phagocytic receptor expressed by microglia in the brain, and is involved in the uptake and clearance of soluble amyloid-β. We therefore asked whether Msr1 might play a role in prion clearance, and assessed the scavenger function of Msr1 in prion pathogenesis. We found that Msr1 expression was upregulated in prion-infected mouse brains. However, Msr1 deficiency did not change prion disease progression or lesion patterns. Prion deposition in Msr1 deficient mice was similar to their wild type littermates. In addition, prion-induced neuroinflammation was not affected by Msr1 ablation. We conclude that Msr1 does not play a major role in prion pathogenesis.


2012 ◽  
Vol 23 (12) ◽  
pp. 1455-1460 ◽  
Author(s):  
Lisa Legault ◽  
Timour Al-Khindi ◽  
Michael Inzlicht

Self-affirmation produces large effects: Even a simple reminder of one’s core values reduces defensiveness against threatening information. But how, exactly, does self-affirmation work? We explored this question by examining the impact of self-affirmation on neurophysiological responses to threatening events. We hypothesized that because self-affirmation increases openness to threat and enhances approachability of unfavorable feedback, it should augment attention and emotional receptivity to performance errors. We further hypothesized that this augmentation could be assessed directly, at the level of the brain. We measured self-affirmed and nonaffirmed participants’ electrophysiological responses to making errors on a task. As we anticipated, self-affirmation elicited greater error responsiveness than did nonaffirmation, as indexed by the error-related negativity, a neural signal of error monitoring. Self-affirmed participants also performed better on the task than did nonaffirmed participants. We offer novel brain evidence that self-affirmation increases openness to threat and discuss the role of error detection in the link between self-affirmation and performance.


Dementia ◽  
2018 ◽  
Vol 17 (8) ◽  
pp. 1045-1054 ◽  
Author(s):  
Sarah Gregory ◽  
Katie Wells ◽  
Kate Forsyth ◽  
Cate Latto ◽  
Helen Szyra ◽  
...  

Aim Despite the growing importance of public and patient involvement in biomedical research, comparatively little attention has been paid to the important role of research participants themselves. Our aim in this paper is to explore the impact research participant involvement has within the PREVENT and the European Prevention of Alzheimer’s Dementia (EPAD) projects. Method In this paper, we report the experiences of involving research participants as collaborators in prospective cohort studies exploring early changes in the brain as pathways towards and risks for dementia. We use minutes and feedback from members of the panel and steering committee to understand the experience and impact on the study. Results We describe the aims and structure of the participant panel established within the PREVENT Dementia study and highlight its contributions to the organisation, conduct and future of the study. Key areas of contribution identified include recruitment, inclusion of additional sub-studies, understanding the participant experience and contributing to the future of the study. Discussion We then describe how the PREVENT Dementia panel forms the basis for participant involvement within EPAD project.


2022 ◽  
Vol 23 (2) ◽  
pp. 846
Author(s):  
Stanislas Martin ◽  
Audrey Foulon ◽  
Wissam El Hage ◽  
Diane Dufour-Rainfray ◽  
Frédéric Denis

The study aimed to examine the impact of the oropharyngeal microbiome in the pathophysiology of schizophrenia and to clarify whether there might be a bidirectional link between the oral microbiota and the brain in a context of dysbiosis-related neuroinflammation. We selected nine articles including three systemic reviews with several articles from the same research team. Different themes emerged, which we grouped into 5 distinct parts concerning the oropharyngeal phageome, the oropharyngeal microbiome, the salivary microbiome and periodontal disease potentially associated with schizophrenia, and the impact of drugs on the microbiome and schizophrenia. We pointed out the presence of phageoma in patients suffering from schizophrenia and that periodontal disease reinforces the role of inflammation in the pathophysiology of schizophrenia. Moreover, saliva could be an interesting substrate to characterize the different stages of schizophrenia. However, the few studies we have on the subject are limited in scope, and some of them are the work of a single team. At this stage of knowledge, it is difficult to conclude on the existence of a bidirectional link between the brain and the oral microbiome. Future studies on the subject will clarify these questions that for the moment remain unresolved.


2020 ◽  
Author(s):  
Benjamin Ng ◽  
Anissa A. Widjaja ◽  
Sivakumar Viswanathan ◽  
Jinrui Dong ◽  
Sonia P. Chothani ◽  
...  

AbstractGenetic loss of function (LOF) in IL11RA infers IL11 signaling as important for fertility, fibrosis, inflammation and craniosynostosis. The impact of genetic LOF in IL11 has not been characterized. We generated IL11-knockout (Il11-/-) mice, which are born in normal Mendelian ratios, have normal hematological profiles and are protected from bleomycin-induced lung fibro-inflammation. Noticeably, baseline IL6 levels in the lungs of Il11-/- mice are lower than those of wild-type mice and are not induced by bleomycin damage, placing IL11 upstream of IL6. Lung fibroblasts from Il11-/- mice are resistant to pro-fibrotic stimulation and show evidence of reduced autocrine IL11 activity. Il11-/- female mice are infertile. Unlike Il11ra1-/- mice, Il11-/- mice do not have a craniosynostosis-like phenotype and exhibit mildly reduced body weights. These data highlight similarities and differences between LOF in IL11 or IL11RA while establishing further the role of IL11 signaling in fibrosis and stromal inflammation.


2021 ◽  
Vol 13 ◽  
Author(s):  
Xiangyue Zhou ◽  
Youwei Li ◽  
Cameron Lenahan ◽  
Yibo Ou ◽  
Minghuan Wang ◽  
...  

Stroke is the destruction of brain function and structure, and is caused by either cerebrovascular obstruction or rupture. It is a disease associated with high mortality and disability worldwide. Brain edema after stroke is an important factor affecting neurologic function recovery. The glymphatic system is a recently discovered cerebrospinal fluid (CSF) transport system. Through the perivascular space and aquaporin 4 (AQP4) on astrocytes, it promotes the exchange of CSF and interstitial fluid (ISF), clears brain metabolic waste, and maintains the stability of the internal environment within the brain. Excessive accumulation of fluid in the brain tissue causes cerebral edema, but the glymphatic system plays an important role in the process of both intake and removal of fluid within the brain. The changes in the glymphatic system after stroke may be an important contributor to brain edema. Understanding and targeting the molecular mechanisms and the role of the glymphatic system in the formation and regression of brain edema after stroke could promote the exclusion of fluids in the brain tissue and promote the recovery of neurological function in stroke patients. In this review, we will discuss the physiology of the glymphatic system, as well as the related mechanisms and therapeutic targets involved in the formation of brain edema after stroke, which could provide a new direction for research against brain edema after stroke.


eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Valentina Vellani ◽  
Lianne P de Vries ◽  
Anne Gaule ◽  
Tali Sharot

Humans are motivated to seek information from their environment. How the brain motivates this behavior is unknown. One speculation is that the brain employs neuromodulatory systems implicated in primary reward-seeking, in particular dopamine, to instruct information-seeking. However, there has been no causal test for the role of dopamine in information-seeking. Here, we show that administration of a drug that enhances dopamine function (dihydroxy-L-phenylalanine; L-DOPA) reduces the impact of valence on information-seeking. Specifically, while participants under Placebo sought more information about potential gains than losses, under L-DOPA this difference was not observed. The results provide new insight into the neurobiology of information-seeking and generates the prediction that abnormal dopaminergic function (such as in Parkinson’s disease) will result in valence-dependent changes to information-seeking.


2000 ◽  
Vol 66 (8) ◽  
pp. 3151-3159 ◽  
Author(s):  
Fabienne Remize ◽  
Emilie Andrieu ◽  
Sylvie Dequin

ABSTRACT Acetic acid plays a crucial role in the organoleptic balance of many fermented products. We have investigated the factors controlling the production of acetate by Saccharomyces cerevisiaeduring alcoholic fermentation by metabolic engineering of the enzymatic steps involved in its formation and its utilization. The impact of reduced pyruvate decarboxylase (PDC), limited acetaldehyde dehydrogenase (ACDH), or increased acetoacetyl coenzyme A synthetase (ACS) levels in a strain derived from a wine yeast strain was studied during alcoholic fermentation. In the strain with the PDC1gene deleted exhibiting 25% of the PDC activity of the wild type, no significant differences were observed in the acetate yield or in the amounts of secondary metabolites formed. A strain overexpressingACS2 and displaying a four- to sevenfold increase in ACS activity did not produce reduced acetate levels. In contrast, strains with one or two disrupted copies of ALD6, encoding the cytosolic Mg2+-activated NADP-dependent ACDH and exhibiting 60 and 30% of wild-type ACDH activity, showed a substantial decrease in acetate yield (the acetate production was 75 and 40% of wild-type production, respectively). This decrease was associated with a rerouting of carbon flux towards the formation of glycerol, succinate, and butanediol. The deletion of ALD4, encoding the mitochondrial K+-activated NAD(P)-linked ACDH, had no effect on the amount of acetate formed. In contrast, a strain lacking both Ald6p and Ald4p exhibited a long delay in growth and acetate production, suggesting that Ald4p can partially replace the Ald6p isoform. Moreover, the ald6 ald4 double mutant was still able to ferment large amounts of sugar and to produce acetate, suggesting the contribution of another member(s) of the ALDfamily.


Development ◽  
1991 ◽  
Vol 112 (4) ◽  
pp. 1063-1075
Author(s):  
M.C. Lienhard ◽  
R.F. Stocker

The development of the sensory neuron pattern in the antennal disc of Drosophila melanogaster was studied with a neuron-specific monoclonal antibody (22C10). In the wild type, the earliest neurons become visible 3 h after pupariation, much later than in other imaginal discs. They lie in the center of the disc and correspond to the neurons of the adult aristal sensillum. Their axons join the larval antennal nerve and seem to establish the first connection towards the brain. Later on, three clusters of neurons appear in the periphery of the disc. Two of them most likely give rise to the Johnston's organ in the second antennal segment. Neurons of the olfactory third antennal segment are formed only after eversion of the antennal disc (clusters t1-t3). The adult pattern of antennal neurons is established at about 27% of metamorphosis. In the mutant lozenge3 (lz3), which lacks basiconic antennal sensilla, cluster t3 fails to develop. This indicates that, in the wild type, a homogeneous group of basiconic sensilla is formed by cluster t3. The possible role of the lozenge gene in sensillar determination is discussed. The homeotic mutant spineless-aristapedia (ssa) transforms the arista into a leg-like tarsus. Unlike leg discs, neurons are missing in the larval antennal disc of ssa. However, the first neurons differentiate earlier than in normal antennal discs. Despite these changes, the pattern of afferents in the ectopic tarsus appears leg specific, whereas in the non-transformed antennal segments a normal antennal pattern is formed. This suggests that neither larval leg neurons nor early aristal neurons are essential for the outgrowth of subsequent afferents.


Hypertension ◽  
2020 ◽  
Vol 76 (Suppl_1) ◽  
Author(s):  
Rohan U Parekh ◽  
Abdel A Abdel-rahman ◽  
Srinivas Sriramula

Hyperactivity of the orexin system contributes to several animal models of hypertension and enhances arginine vasopressin (AVP) release. We previously reported higher neuronal kinin B1 receptor (B1R) expression and brain AVP levels in hypertensive mice. However, the role of B1R and its interaction with orexin system in neurogenic hypertension have not been studied. In the present study, we tested the hypothesis that kinin B1R contributes to hypertension by upregulation of orexin-AVP signaling in the brain. Deoxycorticosterone acetate (DOCA)-salt treatment (1 mg/g body weight DOCA, 1% saline in drinking water, 3 weeks) of wild-type (WT) male mice produced a significant increase in mean arterial pressure (MAP; radio-telemetry) (138 ±3 mmHg, n=8, p<0.01) that was blunted in B1R knockout mice (121±2 mmHg, P <0.05 vs. WT+DOCA). In WT mice, DOCA-salt, compared to vehicle, increased mRNA levels of orexin receptor 1 (2.5 fold, n=9, p<0.001), orexin receptor 2 (3 fold, n=9, p<0.001) and AVP (3 fold, n=9, p<0.01) in the hypothalamic paraventricular nucleus (PVN), and these DOCA-salt evoked effects were attenuated in B1RKO mice. Similarly, DOCA-salt evoked increases in protein expression of orexin receptor 1 and 2 in the hypothalamic PVN of WT mice were attenuated by 25±5% and 33±5% (p<0.05), respectively, in B1RKO vs WT+DOCA mice. Furthermore, DOCA-salt treatment increased plasma AVP levels in WT mice compared to vehicle treated mice (13.69±1.1 vs. 47.86±8.7 pg/ml, p<0.05), but not in B1RKO mice. Together, these data provide novel evidence that kinin B1R plays an important role in mediating DOCA-salt induced hypertension possibly via upregulating the orexin-AVP signaling in the brain.


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