Intracerebral Administration of a Ligand-ASO Conjugate Selectively Reduces α-Synuclein Accumulation in Monoamine Neurons of Double Mutant Human A30P*A53T*α-Synuclein Transgenic Mice

α-Synuclein (α-Syn) protein is involved in the pathogenesis of Parkinson’s disease (PD). Point mutations and multiplications of the α-Syn, which encodes the SNCA gene, are correlated with early-onset PD, therefore the reduction in a-Syn synthesis could be a potential therapy for PD if delivered to the key affected neurons. Several experimental strategies for PD have been developed in recent years using oligonucleotide therapeutics. However, some of them have failed or even caused neuronal toxicity. One limiting step in the success of oligonucleotide-based therapeutics is their delivery to the brain compartment, and once there, to selected neuronal populations. Previously, we developed an indatraline-conjugated antisense oligonucleotide (IND-1233-ASO), that selectively reduces α-Syn synthesis in midbrain monoamine neurons of mice, and nonhuman primates. Here, we extended these observations using a transgenic male mouse strain carrying both A30P and A53T mutant human α-Syn (A30P*A53T*α-Syn). We found that A30P*A53T*α-Syn mice at 4–5 months of age showed 3.5-fold increases in human α-Syn expression in dopamine (DA) and norepinephrine (NE) neurons of the substantia nigra pars compacta (SNc) and locus coeruleus (LC), respectively, compared with mouse α-Syn levels. In parallel, transgenic mice exhibited altered nigrostriatal DA neurotransmission, motor alterations, and an anxiety-like phenotype. Intracerebroventricular IND-1233-ASO administration (100 µg/day, 28 days) prevented the α-Syn synthesis and accumulation in the SNc and LC, and recovered DA neurotransmission, although it did not reverse the behavioral phenotype. Therefore, the present therapeutic strategy based on a conjugated ASO could be used for the selective inhibition of α-Syn expression in PD-vulnerable monoamine neurons, showing the benefit of the optimization of ASO molecules as a disease modifying therapy for PD and related α-synucleinopathies.

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Dual orexin and MCH neuron-ablated mice display severe sleep attacks and cataplexy

eLife ◽

10.7554/elife.54275 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 2

Author(s):

Chi Jung Hung ◽

Daisuke Ono ◽

Thomas S Kilduff ◽

Akihiro Yamanaka

Keyword(s):

Transgenic Mice ◽

Spectral Power ◽

Nrem Sleep ◽

Functional Interaction ◽

Neuronal Populations ◽

Orexin Neuron ◽

Melanin Concentrating Hormone ◽

The Brain ◽

Theta Range

Orexin/hypocretin-producing and melanin-concentrating hormone-producing (MCH) neurons are co-extensive in the hypothalamus and project throughout the brain to regulate sleep/wakefulness. Ablation of orexin neurons decreases wakefulness and results in a narcolepsy-like phenotype, whereas ablation of MCH neurons increases wakefulness. Since it is unclear how orexin and MCH neurons interact to regulate sleep/wakefulness, we generated transgenic mice in which both orexin and MCH neurons could be ablated. Double-ablated mice exhibited increased wakefulness and decreased both rapid eye movement (REM) and non-REM (NREM) sleep. Double-ablated mice showed severe cataplexy compared with orexin neuron-ablated mice, suggesting that MCH neurons normally suppress cataplexy. Double-ablated mice also showed frequent sleep attacks with elevated spectral power in the delta and theta range, a unique state that we call ‘delta-theta sleep’. Together, these results indicate a functional interaction between orexin and MCH neurons in vivo that suggests the synergistic involvement of these neuronal populations in the sleep/wakefulness cycle.

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Quantitative Immunohistochemistry to Measure Regional Expression of Nurr1 in the Brain and the Effect of the Nurr1 Heterozygous Genotype

Frontiers in Neuroanatomy ◽

10.3389/fnana.2021.563854 ◽

2021 ◽

Vol 15 ◽

Author(s):

Evangel Kummari ◽

Shirley X. Guo-Ross ◽

Heath S. Partington ◽

Jennifer Makenzie Nutter ◽

Jeffrey B. Eells

Keyword(s):

Substantia Nigra ◽

Protein Expression ◽

Ventral Tegmental Area ◽

Temporal Cortex ◽

Substantia Nigra Pars Compacta ◽

Expression Levels ◽

Neuronal Populations ◽

Quantitative Immunohistochemistry ◽

Ventral Tegmental ◽

The Brain

The transcription factor Nurr1 is a member of the steroid hormone nuclear receptor superfamily. Ablation of Nurr1 expression arrests mesencephalic dopamine neuron differentiation while attenuation of Nurr1 in the subiculum and hippocampus impairs learning and memory. Additionally, reduced Nurr1 expression has been reported in patients with Parkinson’s disease and Alzheimer’s disease. In order to better understand the overall function of Nurr1 in the brain, quantitative immunohistochemistry was used to measure cellular Nurr1 protein expression, across Nurr1 immunoreactive neuronal populations. Additionally, neuronal Nurr1 expression levels were compared between different brain regions in wild-type mice (+/+) and Nurr1 heterozygous mice (+/−). Regional Nurr1 protein was also investigated at various time points after a seizure induced by pentylenetetrazol (PTZ). Nurr1 protein is expressed in various regions throughout the brain, however, a wide range of Nurr1 expression levels were observed among various neuronal populations. Neurons in the parietal and temporal cortex (secondary somatosensory, insular, auditory, and temporal association cortex) had the highest relative Nurr1 expression (100%) followed closely by the claustrum/dorsal endopiriform cortex (85%) and then subiculum (76%). Lower Nurr1 protein levels were found in neurons in the substantia nigra pars compacta and ventral tegmental area (39%) followed by CA1 (25%) and CA3 (19%) of the hippocampus. Additionally, in the parietal and temporal cortex, two distinct populations of high and medium Nurr1 expressing neurons were observed. Comparisons between +/− and +/+ mice revealed Nurr1 protein was reduced in +/− mice by 27% in the parietal/temporal cortex, 49% in the claustrum/dorsal endopiriform cortex, 25% in the subiculum, 33% in substantia nigra pars compacta, 22% in ventral tegmental area, and 21% in CA1 region of the hippocampus. Based on these data, regional mechanisms appear to exist which can compensate for a loss of a Nurr1 allele. Following a single PTZ-induced seizure, Nurr1 protein in the dentate gyrus peaked around 2 h and returned to baseline by 8 h. Since altered Nurr1 expression has been implicated in neurologic disorders and Nurr1 agonists have showed protective effects, understanding regional protein expression of Nurr1, therefore, is necessary to understand how changes in Nurr1 expression can alter brain function.

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Berberine Alleviates Amyloid-beta Pathogenesis Via Activating LKB1/AMPK Signaling in the Brain of APP/PS1 Transgenic Mice

Current Molecular Medicine ◽

10.2174/1566524019666190315164120 ◽

2019 ◽

Vol 19 (5) ◽

pp. 342-348 ◽

Cited By ~ 2

Author(s):

Zhi-You Cai ◽

Chuan-Ling Wang ◽

Tao-Tao Lu ◽

Wen-Ming Yang

Keyword(s):

Transgenic Mice ◽

Western Blotting ◽

Amyloid Β ◽

Adenosine Monophosphate ◽

Camp Response Element Binding ◽

Enzyme Linked Immunosorbent Assay ◽

Synaptic Density ◽

Ampk Signaling ◽

The Brain ◽

Post Synaptic Density

Background:Liver kinase B1 (LKB1)/5’-adenosine monophosphate-activated protein kinase (AMPK) signaling, a metabolic checkpoint, plays a neuro-protective role in the pathogenesis of Alzheimer’s disease (AD). Amyloid-β (Aβ) acts as a classical biomarker of AD. The aim of the present study was to explore whether berberine (BBR) activates LKB1/AMPK signaling and ameliorates Aβ pathology.Methods:The Aβ levels were detected using enzyme-linked immunosorbent assay and immunohistochemistry. The following biomarkers were measured by Western blotting: phosphorylated (p-) LKB1 (Ser334 and Thr189), p-AMPK (AMPKα and AMPKβ1), synaptophysin, post-synaptic density protein 95 and p-cAMP-response element binding protein (p-CREB). The glial fibrillary acidic protein (GFAP) was determined using Western blotting and immunohistochemistry.Results:BBR inhibited Aβ expression in the brain of APP/PS1 mice. There was a strong up-regulation of both p-LKB1 (Ser334 and Thr189) and p-AMPK (AMPKα and AMPKβ1) in the brains of APP/PS1 transgenic mice after BBR-treatment (P<0.01). BBR promoted the expression of synaptophysin, post-synaptic density protein 95 and p-CREB(Ser133) in the AD brain, compared with the model mice.Conclusion:BBR alleviates Aβ pathogenesis and rescues synapse damage via activating LKB1/AMPK signaling in the brain of APP/PS1 transgenic mice.

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Preclinical Detection of Alpha-Synuclein Seeding Activity in the Colon of a Transgenic Mouse Model of Synucleinopathy by RT-QuIC

Viruses ◽

10.3390/v13050759 ◽

2021 ◽

Vol 13 (5) ◽

pp. 759

Author(s):

Jung-Youn Han ◽

Chaewon Shin ◽

Young Pyo Choi

Keyword(s):

Mouse Model ◽

Transgenic Mice ◽

Lewy Body ◽

Dementia With Lewy Body ◽

Transgenic Mouse Model ◽

Alpha Synuclein ◽

Gi Tract ◽

Colon Tissue ◽

Presymptomatic Stage ◽

The Brain

In synucleinopathies such as Parkinson’s disease (PD) and dementia with Lewy body (DLB), pathological alpha-synuclein (α-syn) aggregates are found in the gastrointestinal (GI) tract as well as in the brain. In this study, using real-time quaking-induced conversion (RT-QuIC), we investigated the presence of α-syn seeding activity in the brain and colon tissue of G2-3 transgenic mice expressing human A53T α-syn. Here we show that pathological α-syn aggregates with seeding activity were present in the colon of G2-3 mice as early as 3 months old, which is in the presymptomatic stage prior to the observation of any neurological abnormalities. In contrast, α-syn seeding activity was not detectable in 3 month-old mouse brains and only identified at 6 months of age in one of three mice. In the symptomatic stage of 12 months of age, RT-QuIC seeding activity was consistently detectable in both the brain and colon of G2-3 mice. Our results indicate that the RT-QuIC assay can presymptomatically detect pathological α-syn aggregates in the colon of G2-3 mice several months prior to their detection in brain tissue.

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Mesencephalic GABA neuronal development: no more on the other side of oblivion

BioMolecular Concepts ◽

10.1515/bmc-2014-0023 ◽

2014 ◽

Vol 5 (5) ◽

pp. 371-382 ◽

Cited By ~ 1

Author(s):

Suyan Li ◽

Sampada Joshee ◽

Anju Vasudevan

Keyword(s):

Transcriptional Control ◽

Neuronal Development ◽

Developmental Regulation ◽

Molecular Characteristics ◽

Psychiatric Illnesses ◽

Neuronal Populations ◽

Gaba Neurons ◽

Recent Developments ◽

And Function ◽

The Brain

AbstractMidbrain GABA neurons, endowed with multiple morphological, physiological and molecular characteristics as well as projection patterns are key players interacting with diverse regions of the brain and capable of modulating several aspects of behavior. The diversity of these GABA neuronal populations based on their location and function in the dorsal, medial or ventral midbrain has challenged efforts to rapidly uncover their developmental regulation. Here we review recent developments that are beginning to illuminate transcriptional control of GABA neurons in the embryonic midbrain (mesencephalon) and discuss its implications for understanding and treatment of neurological and psychiatric illnesses.

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Comparative analysis of CreER transgenic mice for the study of brain macrophages – a case study

10.1101/725218 ◽

2019 ◽

Author(s):

Louise Chappell-Maor ◽

Masha Kolesnikov ◽

Jonathan Grozovski ◽

Jung-Seok Kim ◽

Anat Shemer ◽

...

Keyword(s):

Transgenic Mice ◽

Cre Recombinase ◽

Brain Macrophages ◽

Technological Advances ◽

Communication Circuits ◽

Cell Type Specific ◽

Definition Of ◽

The Brain ◽

Brain Macrophage

AbstractConditional mutagenesis and fate mapping have contributed considerably to our understanding of physiology and pathology. Specifically, Cre recombinase-based approaches allow the definition of cell type-specific contributions to disease development and inter-cellular communication circuits in respective animals models. Here we compared Cx3cr1CreER and Sall1CreER transgenic mice and their use to decipher the brain macrophage compartment as a showcase to discuss recent technological advances. Specifically, we highlight the need to define the accuracy of Cre recombinase expression, as well as strengths and pitfalls of these particular systems that should be taken into consideration when applying these models.

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P.1.01 Modification of histone H3 and H4 in the brain of Tg2576 transgenic mice – implications for Alzheimer's disease

European Neuropsychopharmacology ◽

10.1016/s0924-977x(07)00046-6 ◽

2007 ◽

Vol 17 ◽

pp. S2-S3

Author(s):

C. Unger ◽

C.M. Hernandez ◽

A. Nordberg ◽

J.D. Sweatt

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Transgenic Mice ◽

Histone H3 ◽

The Brain

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Abstract TMP82: Increased Intracerebral Hemorrhage During Acute and Chronic Hypertension in Alzheimer's Transgenic Mice

Stroke ◽

10.1161/str.44.suppl_1.atmp82 ◽

2013 ◽

Vol 44 (suppl_1) ◽

Author(s):

David H Cribbs ◽

Giselle Passos ◽

Vitaly Vasilevko

Keyword(s):

Risk Factor ◽

Transgenic Mice ◽

Intracerebral Hemorrhage ◽

Amyloid Precursor Protein ◽

Significant Risk ◽

Significant Risk Factor ◽

Chronic Hypertension ◽

Cerebrovascular System ◽

The Brain ◽

Tg2576 Mice

Hypertension is a major risk factor for intracerebral hemorrhage (ICH), and the accumulation of amyloid-beta (Aβ) in the cerebrovascular system, cerebral amyloid angiopathy (CAA), is also a significant risk factor for intracerebral hemorrhage ICH. Currently, there are no animal studies demonstrating a direct involvement of hypertension in the accumulation of Alzheimer’s disease-like pathology. To address this issue we have developed several mouse models that combine hypertension protocols with amyloid precursor protein (APP) transgenic mice (Tg2576), which accumulate significant CAA in the large cerebral vessels and the meninges by 18 months of age. The goal of this study was to determine the effect of acute and chronic hypertension on ICH in wildtype and a transgenic mouse model overexpressing a mutant human amyloid precursor protein (Tg2576 mice) associated with early onset AD and CAA. Fifteen-month-old Tg2576 mice and non-transgenic (nTg) littermates were treated with an angiotensin II (AngII) infusion (1000 ng/kg/min) and L-NAME (100 mg/kg/day) in drinking water to produce chronic hypertension. One week later, transient acute hypertension was induced by daily AngII injections (0.5 μg/g, s.c., twice daily) to produce ICH. A similar increase in mean blood pressure was observed in Tg2576 and nTg mice when evaluated 2 weeks after initiation of treatment. However Tg2576 mice had a higher incidence of signs of stroke compared with nTg littermates (P > 0.05). These data suggest that the accumulation of Aβ in the brain has an important role in development of ICH. Moreover, there was robust glial activation and increase in CAA in the gray matter of Tg2576 mice showing that hypertension may affect gray as well as white matter in the brain. Further studies may provide insights into the hypertension-induced changes in the cerebral vascular system that initiated the increase in CAA. The accumulation of Aβ in the cerebrovascular system is a significant risk factor for intracerebral hemorrhage (ICH), and has been linked to endothelial transport failure and blockage of perivascular drainage. While management of hypertension and atherosclerosis can reduce the incidence of ICH, there are currently no approved therapies for attenuating CAA.

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Progesterone receptors in AVPV kisspeptin neurons are sufficient for positive feedback induction of the LH surge

Endocrinology ◽

10.1210/endocr/bqab161 ◽

2021 ◽

Author(s):

Margaret A Mohr ◽

Lourdes A Esparza ◽

Paige Steffen ◽

Paul E Micevych ◽

Alexander S Kauffman

Keyword(s):

Luteinizing Hormone ◽

Transgenic Mice ◽

Positive Feedback ◽

Progesterone Receptors ◽

Critical Importance ◽

Estrogen And Progesterone Receptors ◽

Lh Surge ◽

Normal Fertility ◽

Gnrh Neurons ◽

The Brain

Abstract Kisspeptin, encoded by Kiss1, stimulates GnRH neurons to govern reproduction. In female rodents, estrogen-sensitive kisspeptin neurons in the rostral anteroventral periventricular (AVPV) hypothalamus are thought to mediate estradiol (E2)-induced positive feedback induction of the preovulatory luteinizing hormone (LH) surge. AVPV kisspeptin neurons co-express estrogen and progesterone receptors (PGR) and are activated during the LH surge. While E2 effects on kisspeptin neurons have been well-studied, progesterone’s regulation of kisspeptin neurons is less understood. Using transgenic mice lacking PGR exclusively in kisspeptin cells (termed KissPRKOs), we previously demonstrated that progesterone action specifically in kisspeptin cells is essential for ovulation and normal fertility. Unlike control females, KissPRKO females did not generate proper LH surges, indicating that PGR signaling in kisspeptin cells is required for proper positive feedback. However, since PGR was knocked out from all kisspeptin neurons in the brain, that study was unable to determine the specific kisspeptin population mediating PGR action on the LH surge. Here, we used targeted Cre-mediated AAV technology to re-introduce PGR selectively into AVPV kisspeptin neurons of adult KissPRKO females, and tested whether this rescues occurrence of the LH surge. We found that targeted upregulation of PGR in kisspeptin neurons exclusively in the AVPV is sufficient to restore proper E2-induced LH surges in KissPRKO females, suggesting that this specific kisspeptin population is a key target of the necessary progesterone action for the surge. These findings further highlight the critical importance of progesterone signaling, along with E2 signaling, in the positive feedback induction of LH surges and ovulation.

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