scholarly journals Senescent Accelerated Prone 8 (SAMP8) Mice as A Model of Age Dependent Neuroinflammation

2020 ◽  
Author(s):  
Andrés Fernández ◽  
Elena Quintana ◽  
Patricia Velasco ◽  
Belén de Andrés ◽  
Maria Luisa Gaspar ◽  
...  
Keyword(s):  
Choroid Plexus ◽  
Inflammatory Cytokines ◽  
Hippocampal Formation ◽  
Morphological Changes ◽  
Interleukin 1 ◽  
Brain Parenchyma ◽  
Age Related ◽  
Inflammatory Changes ◽  
Samp8 Mice ◽  
The Brain

Abstract Background: Aging and age related diseases are strong risk factors for the development of neurodegenerative diseases. Neuroinflammation (NIF), as the brain's immune response, plays an important role in aged associated degeneration of central nervous system (CNS). The need of animal models that will allow us to understand and modulate this process is required for the scientific community. Methods: We have analyzed aging-phenotypical and inflammatory changes of brain myeloid cells (bMyC) in a senescent accelerated prone aged (SAMP8) mouse model, and compared with their resistant to senescence control (SAMR1). We have performed morphometric methods to evaluate the architecture of cellular prolongations and analyzed Iba1+ clustered cells with aging. To analyse specific constant brain areas we have performed stereology measurements of Iba1+ cells in the hippocampal formation. We have isolated bMyC from brain parenchyma (BP) and choroid plexus and meningeal membranes (m/Ch), and analyzed their response to systemic LPS- driven inflammation.Results: Aged 10 month old SAMP8 mice presents many of the hallmarks of aging-dependent neuroinflammation when compared with their senescence resistant control (SAMR1); ie, increase of protein aggregates, presence of Iba1+ clusters, but not increase in the number of Iba1+ cells. We have further observed and increased of main inflammatory mediator IL-1β, and augment of border MHCII+Iba1+ cells. Isolated CD45+ bMyC from brain parenchyma (BP) and choroid plexus and meningeal membranes (m/Ch) have been analyzed showing that there is not significant increase of CD45+ from the periphery. Our data support that aged-driven pro-inflammatory cytokine interleukin 1 beta (IL1β) transcription is mainly enhanced in CD45+BP cells. Furthermore, we are showing that LPS-driven systemic inflammation produces inflammatory cytokines mainly in the border bMyC, sensed to a lesser extent by the BP bMyC, and is enhanced in aged SAMP8 compared to control SAMR1.Conclusion: Our data validate the SAMP8 model to study age-associated neuroinflammatory events, but careful controls for age and strain are required. These animals show morphological changes in their bMyC cell repertoires associated to age, corresponding to an increase in the production of main pro inflammatory cytokines such as IL-1β, which predispose the brain to an enhanced inflammatory response after LPS-systemic challenge.

scholarly journals Senescent accelerated prone 8 (SAMP8) mice as a model of age dependent neuroinflammation

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Andrés Fernández ◽  
Elena Quintana ◽  
Patricia Velasco ◽  
Belén Moreno-Jimenez ◽  
Belén de Andrés ◽  
...  
Keyword(s):  
Choroid Plexus ◽  
Inflammatory Cytokines ◽  
Hippocampal Formation ◽  
Morphological Changes ◽  
Interleukin 1 ◽  
Brain Parenchyma ◽  
Age Related ◽  
Inflammatory Changes ◽  
Samp8 Mice ◽  
The Brain

Abstract Background Aging and age-related diseases are strong risk factors for the development of neurodegenerative diseases. Neuroinflammation (NIF), as the brain’s immune response, plays an important role in aged associated degeneration of central nervous system (CNS). There is a need for well characterized animal models that will allow the scientific community to understand and modulate this process. Methods We have analyzed aging-phenotypical and inflammatory changes of brain myeloid cells (bMyC) in a senescent accelerated prone aged (SAMP8) mouse model, and compared with their senescence resistant control mice (SAMR1). We have performed morphometric methods to evaluate the architecture of cellular prolongations and determined the appearance of Iba1+ clustered cells with aging. To analyze specific constant brain areas, we have performed stereology measurements of Iba1+ cells in the hippocampal formation. We have isolated bMyC from brain parenchyma (BP) and choroid plexus plus meningeal membranes (m/Ch), and analyzed their response to systemic lipopolysaccharide (LPS)-driven inflammation. Results Aged 10 months old SAMP8 mice present many of the hallmarks of aging-dependent neuroinflammation when compared with their SAMR1 control, i.e., increase of protein aggregates, presence of Iba1+ clusters, but not an increase in the number of Iba1+ cells. We have further observed an increase of main inflammatory mediator IL-1β, and an augment of border MHCII+Iba1+ cells. Isolated CD45+ bMyC from brain parenchyma (BP) and choroid plexus plus meningeal membranes (m/Ch) have been analyzed, showing that there is not a significant increase of CD45+ cells from the periphery. Our data support that aged-driven pro-inflammatory cytokine interleukin 1 beta (IL-1β) transcription is enhanced in CD45+BP cells. Furthermore, LPS-driven systemic inflammation produces inflammatory cytokines mainly in border bMyC, sensed to a lesser extent by the BP bMyC, showing that IL-1β expression is further augmented in aged SAMP8 compared to control SAMR1. Conclusion Our data validate the SAMP8 model to study age-associated neuroinflammatory events, but careful controls for age and strain are required. These animals show morphological changes in their bMyC cell repertoires associated to age, corresponding to an increase in the production of pro-inflammatory cytokines such as IL-1β, which predispose the brain to an enhanced inflammatory response after LPS-systemic challenge.

Analysis of Changes in Signal Intensity of Choroid Plexus in MRI Using FLAIR-DW-EPI Pulse Sequence

2020 ◽  
Vol 3 (1) ◽  
pp. 9-15
Author(s):  
Jingyu Kim ◽  
◽  
Sang-Jin Im ◽  
Keyword(s):  
Choroid Plexus ◽  
Signal Intensity ◽  
Pulse Sequence ◽  
Signal Strength ◽  
Brain Parenchyma ◽  
Weighted Image ◽  
Diffusion Weighted ◽  
Water Signal ◽  
The Brain ◽  
Functional Problems

In this study, the signal intensity of choroid plexus, which is producing cerebrospinal fluid, is analyzed according to the FLAIR diffusion-weighted imaging technique. In the T2*-DW-EPI diffusion-weighted image, the FLAIR-DW-EPI technique, which suppressed the water signal, was additionally examined for subjects with high choroid plexus signals and compared and analyzed the signal intensity. As a result of the experiment, it was confirmed that the FLAIR-DW-EPI technique showed a signal strength equal to or lower than that of the brain parenchyma, and there was a difference in signal strength between the two techniques. As a result of this study, if the choroidal plexus signal is high in the T2 * -DW-EPI diffusionweighted image, additional examination of the FLAIR-DW-EPI technique is thought to be useful in distinguishing functional problems of the choroid plexus. In conclusion, if the choroidal plexus signal is high on the T2*-DW-EPI diffuse weighted image, it is thought that further examination of the FLAIR-DW-EPI technique will be useful in distinguishing functional problems of the choroidal plexus.

scholarly journals Metabolic Plasticity of Astrocytes and Aging of the Brain

2019 ◽  
Vol 20 (4) ◽  
pp. 941 ◽  
Author(s):  
Mitsuhiro Morita ◽  
Hiroko Ikeshima-Kataoka ◽  
Marko Kreft ◽  
Nina Vardjan ◽  
Robert Zorec ◽  
...  
Keyword(s):  
Systemic Circulation ◽  
Brain Parenchyma ◽  
Acid Oxidation ◽  
Normal Brain ◽  
Atp Production ◽  
Metabolic Plasticity ◽  
Neuronal Synapses ◽  
Age Related ◽  
Pathologic Processes ◽  
The Brain

As part of the blood-brain-barrier, astrocytes are ideally positioned between cerebral vasculature and neuronal synapses to mediate nutrient uptake from the systemic circulation. In addition, astrocytes have a robust enzymatic capacity of glycolysis, glycogenesis and lipid metabolism, managing nutrient support in the brain parenchyma for neuronal consumption. Here, we review the plasticity of astrocyte energy metabolism under physiologic and pathologic conditions, highlighting age-dependent brain dysfunctions. In astrocytes, glycolysis and glycogenesis are regulated by noradrenaline and insulin, respectively, while mitochondrial ATP production and fatty acid oxidation are influenced by the thyroid hormone. These regulations are essential for maintaining normal brain activities, and impairments of these processes may lead to neurodegeneration and cognitive decline. Metabolic plasticity is also associated with (re)activation of astrocytes, a process associated with pathologic events. It is likely that the recently described neurodegenerative and neuroprotective subpopulations of reactive astrocytes metabolize distinct energy substrates, and that this preference is supposed to explain some of their impacts on pathologic processes. Importantly, physiologic and pathologic properties of astrocytic metabolic plasticity bear translational potential in defining new potential diagnostic biomarkers and novel therapeutic targets to mitigate neurodegeneration and age-related brain dysfunctions.

Age-related changes in microglial physiology: the role for healthy brain ageing and neurodegenerative disorders

e-Neuroforum ◽  
2017 ◽  
Vol 23 (4) ◽  
Author(s):  
Olga Garaschuk
Keyword(s):  
Neurodegenerative Disorders ◽  
Healthy Aging ◽  
Molecular Mechanisms ◽  
Brain Parenchyma ◽  
Immune Defense ◽  
Synaptic Activity ◽  
Mammalian Brain ◽  
Age Related ◽  
Brain Ageing ◽  
The Brain

AbstractMicroglia are the main immune cells of the brain contributing, however, not only to brain’s immune defense but also to many basic housekeeping functions such as development and maintenance of functional neural networks, provision of trophic support for surrounding neurons, monitoring and modulating the levels of synaptic activity, cleaning of accumulating extracellular debris and repairing microdamages of the brain parenchyma. As a consequence, age-related alterations in microglial function likely have a manifold impact on brain’s physiology. In this review, I discuss the recent data about physiological properties of microglia in the adult mammalian brain; changes observed in the brain innate immune system during healthy aging and the probable biological mechanisms responsible for them as well as changes occurring in humans and mice during age-related neurodegenerative disorders along with underlying cellular/molecular mechanisms. Together these data provide a new conceptual framework for thinking about the role of microglia in the context of age-mediated brain dysfunction.

Age-related autophagy alterations in the brain of senescence accelerated mouse prone 8 (SAMP8) mice

2011 ◽  
Vol 46 (7) ◽  
pp. 533-541 ◽  
Author(s):  
Qinying Ma ◽  
Jing Qiang ◽  
Ping Gu ◽  
Yanyong Wang ◽  
Yuan Geng ◽  
...  
Keyword(s):  
Age Related ◽  
Samp8 Mice ◽  
The Brain ◽  
Senescence Accelerated Mouse

scholarly journals High Levels of β-Amyloid, Tau, and Phospho-Tau in Red Blood Cells as Biomarkers of Neuropathology in Senescence-Accelerated Mouse

2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Rebecca Piccarducci ◽  
Deborah Pietrobono ◽  
Carolina Pellegrini ◽  
Simona Daniele ◽  
Matteo Fornai ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Inflammatory Marker ◽  
Interleukin 1 ◽  
Biochemical Alterations ◽  
Amyloid A ◽  
Accumulation Kinetics ◽  
Samp8 Mice ◽  
The Brain ◽  
Senescence Accelerated Mouse

Alzheimer’s Disease (AD) is the most common Neurodegenerative Disease (ND), primarily characterised by neuroinflammation, neuronal plaques of β-amyloid (Aβ), and neurofibrillary tangles of hyperphosphorylated tau. α-Synuclein (α-syn) and its heteroaggregates with Aβ and tau have been recently included among the neuropathological elements of NDs. These pathological traits are not restricted to the brain, but they reach peripheral fluids as well. In this sense, Red Blood Cells (RBCs) are emerging as a good model to investigate the biochemical alterations of aging and NDs. Herein, the levels of homo- and heteroaggregates of ND-related proteins were analysed at different stages of disease progression. In particular, a validated animal model of AD, the SAMP8 (Senescence-Accelerated Mouse-Prone) and its control strain SAMR1 (Senescence-Accelerated Mouse-Resistant) were used in parallel experiments. The levels of the aforementioned proteins and of the inflammatory marker interleukin-1β (IL-1β) were examined in both brain and RBCs of SAMP8 and SAMR1 at 6 and 8 months. Brain Aβ, tau, and phospho-tau (p-tau) were higher in SAMP8 mice than in control mice and increased with AD progression. Similar accumulation kinetics were found in RBCs, even if slower. By contrast, α-syn and its heterocomplexes (α-syn-Aβ and α-syn-tau) displayed different accumulation kinetics between brain tissue and RBCs. Both brain and peripheral IL-1β levels were higher in SAMP8 mice, but increased sooner in RBCs, suggesting that inflammation might initiate at a peripheral level before affecting the brain. In conclusion, these results confirm RBCs as a valuable model for monitoring neurodegeneration, suggesting peripheral Aβ, tau, and p-tau as potential early biomarkers of AD.

scholarly journals Noggin rescues age-related stem cell loss in the brain of senescent mice with neurodegenerative pathology

2018 ◽  
Vol 115 (45) ◽  
pp. 11625-11630 ◽  
Author(s):  
María Díaz-Moreno ◽  
Tomás Armenteros ◽  
Simona Gradari ◽  
Rafael Hortigüela ◽  
Laura García-Corzo ◽  
...  
Keyword(s):  
Healthy Aging ◽  
Late Onset ◽  
Hippocampal Neurogenesis ◽  
Bmp Signaling ◽  
In Vitro Assays ◽  
Age Related ◽  
Samp8 Mice ◽  
The Brain

Increasing age is the greatest known risk factor for the sporadic late-onset forms of neurodegenerative disorders such as Alzheimer’s disease (AD). One of the brain regions most severely affected in AD is the hippocampus, a privileged structure that contains adult neural stem cells (NSCs) with neurogenic capacity. Hippocampal neurogenesis decreases during aging and the decrease is exacerbated in AD, but the mechanistic causes underlying this progressive decline remain largely unexplored. We here investigated the effect of age on NSCs and neurogenesis by analyzing the senescence accelerated mouse prone 8 (SAMP8) strain, a nontransgenic short-lived strain that spontaneously develops a pathological profile similar to that of AD and that has been employed as a model system to study the transition from healthy aging to neurodegeneration. We show that SAMP8 mice display an accelerated loss of the NSC pool that coincides with an aberrant rise in BMP6 protein, enhanced canonical BMP signaling, and increased astroglial differentiation. In vitro assays demonstrate that BMP6 severely impairs NSC expansion and promotes NSC differentiation into postmitotic astrocytes. Blocking the dysregulation of the BMP pathway and its progliogenic effect in vivo by intracranial delivery of the antagonist Noggin restores hippocampal NSC numbers, neurogenesis, and behavior in SAMP8 mice. Thus, manipulating the local microenvironment of the NSC pool counteracts hippocampal dysfunction in pathological aging. Our results shed light on interventions that may allow taking advantage of the brain’s natural plastic capacity to enhance cognitive function in late adulthood and in chronic neurodegenerative diseases such as AD.

scholarly journals Distribution of Suramin, an Antitrypanosomal Drug, across the Blood-Brain and Blood-Cerebrospinal Fluid Interfaces in Wild-Type and P-Glycoprotein Transporter-Deficient Mice

2007 ◽  
Vol 51 (9) ◽  
pp. 3136-3146 ◽  
Author(s):  
Lisa Sanderson ◽  
Adil Khan ◽  
Sarah Thomas
Keyword(s):  
Choroid Plexus ◽  
Brain Perfusion ◽  
Brain Parenchyma ◽  
Sleeping Sickness ◽  
New Drugs ◽  
Wild Type ◽  
P Glycoprotein ◽  
Blood Brain ◽  
Targeted Mutation ◽  
The Brain

ABSTRACT Although 60 million people are exposed to human African trypanosomiasis, drug companies have not been interested in developing new drugs due to the lack of financial reward. No new drugs will be available for several years. A clearer understanding of the distribution of existing drugs into the brains of sleeping sickness patients is needed if we are to use the treatments that are available more safely and effectively. This proposal addresses this issue by using established animal models. Using in situ brain perfusion and isolated incubated choroid plexus techniques, we investigated the distribution of [3H]suramin into the central nervous systems (CNSs) of male BALB/c, FVB (wild-type), and P-glycoprotein-deficient (Mdr1a/Mdr1b-targeted mutation) mice. There was no difference in the [3H]suramin distributions between the three strains of mice. [3H]suramin had a distribution similar to that of the vascular marker, [14C]sucrose, into the regions of the brain parenchyma that have a blood-brain barrier. However, the association of [3H]suramin with the circumventricular organ samples, including the choroid plexus, was higher than that of [14C]sucrose. The association of [3H]suramin with the choroid plexus was also sensitive to phenylarsine oxide, an inhibitor of endocytosis. The distribution of [3H]suramin to the brain was not affected by the presence of other antitrypanosomal drugs or the P-glycoprotein efflux transporter. Overall, the results confirm that [3H]suramin would be unlikely to treat the second or CNS stage of sleeping sickness.

scholarly journals Spike protein multiorgan tropism suppressed by antibodies targeting SARS-CoV-2

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Molly Brady ◽  
Conor McQuaid ◽  
Alexander Solorzano ◽  
Angelique Johnson ◽  
Abigail Combs ◽  
...  
Keyword(s):  
Choroid Plexus ◽  
Imaging System ◽  
Brain Parenchyma ◽  
Dynamic Imaging ◽  
Spike Protein ◽  
Tissue Analysis ◽  
Organ Uptake ◽  
Organ Specific ◽  
The Brain

AbstractWhile there is SARS-CoV-2 multiorgan tropism in severely infected COVID-19 patients, it’s unclear if this occurs in healthy young individuals. In addition, for antibodies that target the spike protein (SP), it’s unclear if these reduce SARS-CoV-2/SP multiorgan tropism equally. We used fluorescently labeled SP-NIRF to study viral behavior, using an in vivo dynamic imaging system and ex in vivo tissue analysis, in young mice. We found a SP body-wide biodistribution followed by a slow regional elimination, except for the liver, which showed an accumulation. SP uptake was highest for the lungs, and this was followed by kidney, heart and liver, but, unlike the choroid plexus, it was not detected in the brain parenchyma or CSF. Thus, the brain vascular barriers were effective in restricting the entry of SP into brain parenchyma in young healthy mice. While both anti-ACE2 and anti-SP antibodies suppressed SP biodistribution and organ uptake, anti-SP antibody was more effective. By extension, our data support the efficacy of these antibodies on SARS-CoV-2 multiorgan tropism, which could determine COVID-19 organ-specific outcomes.

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