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1.
Cells ; 13(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39273079

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting both upper and lower motor neurons. While there have been many potential factors implicated for ALS development, such as oxidative stress and mitochondrial dysfunction, no exact mechanism has been determined at this time. Nicotinamide adenine dinucleotide (NAD+) is one of the most abundant metabolites in mammalian cells and is crucial for a broad range of cellular functions from DNA repair to energy homeostasis. NAD+ can be synthesized from three different intracellular pathways, but it is the NAD+ salvage pathway that generates the largest proportion of NAD+. Impaired NAD+ homeostasis has been connected to aging and neurodegenerative disease-related dysfunctions. In ALS mice, NAD+ homeostasis is potentially disrupted prior to the appearance of physical symptoms and is significantly reduced in the nervous system at the end stage. Treatments targeting NAD+ metabolism, either by administering NAD+ precursor metabolites or small molecules that alter NAD+-dependent enzyme activity, have shown strong beneficial effects in ALS disease models. Here, we review the therapeutic interventions targeting NAD+ metabolism for ALS and their effects on the most prominent pathological aspects of ALS in animal and cell models.


Assuntos
Esclerose Lateral Amiotrófica , NAD , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , NAD/metabolismo , Humanos , Animais , Modelos Animais de Doenças
2.
Elife ; 122024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287624

RESUMO

Central noradrenergic (NA) neurons are key constituents of the respiratory homeostatic network. NA dysfunction is implicated in several developmental respiratory disorders including Congenital Central Hyperventilation Syndrome (CCHS), Sudden Infant Death Syndrome (SIDS), and Rett Syndrome. The current unchallenged paradigm in the field, supported by multiple studies, is that glutamate co-transmission in subsets of central NA neurons plays a role in breathing control. If true, NA-glutamate co-transmission may also be mechanistically important in respiratory disorders. However, the requirement of NA-derived glutamate in breathing has not been directly tested and the extent of glutamate co-transmission in the central NA system remains uncharacterized. Therefore, we fully characterized the cumulative fate maps and acute adult expression patterns of all three vesicular glutamate transporters (Slc17a7 (Vglut1), Slc17a6 (Vglut2), and Slc17a8 (Vglut3)) in NA neurons, identifying a novel, dynamic expression pattern for Vglut2 and an undescribed co-expression domain for Vglut3 in the NA system. In contrast to our initial hypothesis that NA-derived glutamate is required to breathing, our functional studies showed that loss of Vglut2 throughout the NA system failed to alter breathing or metabolism under room air, hypercapnia, or hypoxia in unrestrained and unanesthetized mice. These data demonstrate that Vglut2-based glutamatergic signaling within the central NA system is not required for normal baseline breathing and hypercapnic, hypoxic chemosensory reflexes. These outcomes challenge the current understanding of central NA neurons in the control of breathing and suggests that glutamate may not be a critical target to understand NA neuron dysfunction in respiratory diseases.


Assuntos
Neurônios Adrenérgicos , Ácido Glutâmico , Respiração , Transdução de Sinais , Proteína Vesicular 2 de Transporte de Glutamato , Animais , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/genética , Camundongos , Ácido Glutâmico/metabolismo , Neurônios Adrenérgicos/metabolismo , Neurônios Adrenérgicos/fisiologia , Reflexo/fisiologia , Masculino , Feminino
3.
BMJ Open ; 14(9): e086427, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289014

RESUMO

INTRODUCTION: Several systematic reviews and meta-analyses (SRs/MAs) of clinical trials showed the efficacy of acupuncture for post-stroke motor impairment. To systematically estimate and synthesise these results, we aimed to conduct an overview of SRs/MAs to summarise the evidence and evaluate the methodological quality regarding the effectiveness and safety of acupuncture for post-stroke motor impairment. METHODS AND ANALYSIS: This is a protocol for an overview of SRs/MAs. A literature search will be conducted in PubMed, Embase, Web of Science and Cochrane Central Registry of Controlled Trials from the construction of the database to March 2024. SRs/MAs evaluating the efficacy of acupuncture in post-stroke motor impairment patients will be included. Two independent investigators will screen and evaluate related SRs/MAs back-to-back. We will extract data into a predefined form designed to summarise the key characteristics of each study. The evaluation of methodological quality of the included SRs/MAs will be assessed using AMSTAR-2, the PRISMA 2020 checklist and the GRADE grading system. ETHICS AND DISSEMINATION: Ethics approval is not required for this overview as we will only analyse published literature. The results will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42024502006.


Assuntos
Terapia por Acupuntura , Metanálise como Assunto , Reabilitação do Acidente Vascular Cerebral , Revisões Sistemáticas como Assunto , Humanos , Terapia por Acupuntura/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Projetos de Pesquisa , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia
4.
Sci Rep ; 14(1): 21654, 2024 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289437

RESUMO

To investigate the spinal cord neuron apoptosis and neuroprotective mechanism of nerve growth factorganismsor (NGF) gene mediated by recombinant adenovirus (Ad-NGF) via peripheral transfection in mice with experimental autoimmune encephalomyelitis (EAE). Forty healthy female C57BL/6 mice were randomly divided into a control group, adenovirus (AdV) group, EAE group, and Ad-NGF transfection group; the control group received no treatment; the AdV group received adenovirus injection via the tail vein; the EAE and Ad-NGF transfection groups were induced with experimental autoimmune encephalomyelitis (EAE) using myelin oligodendrocyte glycoprotein 35-55 (MOG35-55), Ad-NGF transfection group received Ad-NGF injection via the tail vein, and daily neurological impairment scores were obtained. AQThe TUNEL method was employed to observe spinal neuron apoptosis in each group of mice; protein immunoblotting (western blot) and RT-PCR were used to measure NGF levels in the spinal cord tissues of each group, and western blotting was used to assess levels of cleaved caspase-3, Bax, and Bcl-2. ELISA and RT-PCR were employed to detect protein and mRNA levels of neuron-specific enolase (NSE) in spinal cord tissues, respectively. The control group and AdV mice did not develop symptoms. Compared to the EAE group, in the Ad-NGF transfection group, neurological function scores, TUNEL-positive cell counts, the ratio of NeuN + TUNEL to NeuN, levels of Bax and cleaved caspase-3 apoptotic proteins were significantly reduced, while Bcl-2 protein expression was increased. Expression levels of NGF, NGF-mRNA, NSE, and NSE-mRNA in spinal cord tissues were significantly elevated (P < 0.01). Immunofluorescence labeling revealed a significant punctate aggregation of apoptotic cells in spinal neurons of the EAE group, while the aggregation phenomenon was less pronounced in the Ad-NGF transfection group. Ad-NGF transfected by the periphery has a protective effect on spinal cord neurons in EAE mice by up-regulation NGF level, down-regulating apoptotic protein Caspase-3 in spinal cord neurons, inhibiting spinal cord neuron apoptosis and promoting NSE expression.


Assuntos
Adenoviridae , Apoptose , Encefalomielite Autoimune Experimental , Camundongos Endogâmicos C57BL , Fator de Crescimento Neural , Neurônios , Medula Espinal , Transfecção , Animais , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Adenoviridae/genética , Medula Espinal/metabolismo , Medula Espinal/patologia , Camundongos , Neurônios/metabolismo , Feminino , Encefalomielite Autoimune Experimental/terapia , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Neuroproteção , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagem , Terapia Genética/métodos
5.
Curr Biol ; 34(18): 4332-4337.e2, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39232564

RESUMO

Dragonflies are poikilothermic animals with limited thermoregulation; therefore, their entire bodies, including the brain, experience a range of temperatures during their daily activities.1,2 These flying insects exhibit hunting prowess, pursuing prey or conspecifics whether in direct sunlight or under the cover of cloud.3,4 Likely to underlie these aerobatic feats are the small target motion detector (STMD) neurons.5 These visual neurons are sensitive to target contrast and tuned to the target's size and velocity, with some neurons exhibiting complex predictive and selective properties, well suited for prey interception and feeding amid swarms.3,4,6,7,8,9 Increased temperature can modulate the biochemical processes underlying neuronal processing, increasing sensitivity and quickening the responsiveness of insect photoreceptors and downstream optic flow neurons,10,11,12 while in other neuronal pathways, compensatory processes have been shown to account for temperature changes.13,14 We determined the ethological range of temperatures experienced by the dragonfly, Hemicordulia tau, in its natural environment. Across this behaviorally relevant range, we showed increased temperatures having a large 8.7-fold increase in the contrast sensitivity of STMD neurons. However, suppression of responses to larger targets was unaltered. STMD tuning for target velocities was changed remarkably, not only increasing the optimum but extending the fastest velocities encoded by an order of magnitude. These results caution against interpreting functionality underlying spike rates at constrained, experimental temperatures. Moreover, they raise intriguing new questions about how information is represented within the brain of these flying insects, given the relationship between visual stimulus parameters and neuronal activity varies so dramatically depending on current environmental conditions.


Assuntos
Percepção de Movimento , Odonatos , Temperatura , Animais , Odonatos/fisiologia , Percepção de Movimento/fisiologia , Neurônios/fisiologia
6.
ACS Appl Mater Interfaces ; 16(37): 49724-49732, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39241231

RESUMO

Two-dimensional graphene and graphene-based materials are attracting increasing interest in neuromorphic computing applications by the implementation of memristive architectures that enable the closest solid-state equivalent to biological synapses and neurons. However, the state-of-the-art fabrication methodology involves routine use of high-temperature processes and multistepped chemical synthesis, often on a rigid substrate constraining the experimental exploration in the field to high-tech facilities. Here, we demonstrate the use of a one-step process using a commercial laser to fabricate laser-induced graphene (LIG) memristors directly on a flexible polyimide substrate. For the first time, a volatile resistive switching phenomenon is reported in the LIG without using any additional materials. The absence of any precursor or patterning mask greatly simplifies the process while reducing the cost and providing greater controllability. The fabricated memristors show multilevel resistance-switching characteristics with high endurance and tunable timing characteristics. The recovery time and the trigger pulse-dependent state change are shown to be highly suitable for its use as a synaptic element and in the realization of leaky-integrate and fire neuron in neuromorphic circuits.

7.
CNS Neurosci Ther ; 30(9): e14872, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39328029

RESUMO

AIM: Most of the subarachnoid hemorrhage (SAH) patients experienced the symptom of severe headache caused by intracranial hypertension. Piezo1 is a mechanosensitive ion channel protein. This study aimed to investigate the effect of Piezo1 on neurons in response to intracranial hypertension. METHODS: The SAH rat model was performed by the modified endovascular perforation method. Piezo1 inhibitor GsMTx4 was administered intraperitoneally after SAH induction. To investigate the underlying mechanism, the selective Piezo1 agonist Yoda1, Piezo1 shRNA, and MY-875 were administered via intracerebroventricular injection before SAH induction. In vitro, we designed a pressurizing device to exclusively explore the effect of Piezo1 activation on primary neurons. Neurons were pretreated with Piezo1 inhibition followed by intracranial hypertension treatment, and then apoptosis-related proteins were detected. RESULTS: Piezo1 inhibition significantly attenuated neuronal apoptosis and improved the outcome of neurological deficits in rats after SAH. The Hippo pathway agonist MY-875 reversed the anti-apoptotic effects of Piezo1 knockdown. In vitro, intracranial hypertension mimicked by the pressurizing device induced Piezo1 expression, resulting in Hippo pathway activation and neuronal apoptosis. The Hippo pathway inhibitor Xmu-mp-1 attenuated Yoda1-induced neuronal apoptosis. In addition, the combination of hypertension and oxyhemoglobin treatment exacerbated neuronal apoptosis. CONCLUSIONS: Intracranial hypertension induced Piezo1 expression, neuronal apoptosis, and the Hippo pathway activation; the Hippo signaling pathway is involved in Piezo1 activation-induced neuronal apoptosis in respond to intracranial hypertension. Primary neurons treated with intracranial hypertension and oxyhemoglobin together can better characterize the circumstance of SAH in vivo, which is contributed to construct an ideal in vitro SAH model.


Assuntos
Apoptose , Hipertensão Intracraniana , Neurônios , Proteínas Serina-Treonina Quinases , Ratos Sprague-Dawley , Hemorragia Subaracnóidea , Animais , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Apoptose/fisiologia , Apoptose/efeitos dos fármacos , Ratos , Masculino , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Hemorragia Subaracnóidea/complicações , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Canais Iônicos/metabolismo , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos , Tiofenos/farmacologia , Tiadiazóis/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Oligopeptídeos/farmacologia , Pirazinas , Venenos de Aranha , Peptídeos e Proteínas de Sinalização Intercelular
8.
Cureus ; 16(8): e67865, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39328605

RESUMO

Paraneoplastic neurological syndromes (PNS) are a rare and diverse group of disorders caused by immune-mediated effects of malignancies. These syndromes are very rare and often present diagnostic and therapeutic challenges. Motor neuron disease as a paraneoplastic condition is particularly uncommon, especially in association with gastrointestinal malignancies like sigmoid colon adenocarcinoma. A 62-year-old male with type 2 diabetes mellitus (T2DM) presented with chronic diarrhea and a three-year history of progressive bilateral limb weakness. Initial symptoms were attributed to diabetic neuropathy, but the rapid progression and severity warranted further investigation. Neurological examination revealed hypotonia, muscle wasting, and absent reflexes in all four limbs. Diagnostic tests, including electromyography (EMG) and nerve conduction studies, confirmed motor sensory axonal neuropathy. A colonoscopy revealed a mass in the sigmoid colon, and a biopsy confirmed adenocarcinoma. The patient was managed with surgical resection of the tumor, adjuvant chemotherapy, and immunomodulatory treatments, resulting in the stabilization of neurological symptoms. This case highlights the importance of considering paraneoplastic syndromes in patients with unexplained neurological symptoms, particularly when a malignancy is suspected or known. Early recognition and a multidisciplinary approach are crucial for improving patient outcomes. Further research is needed to understand the pathophysiological mechanisms and develop sensitive biomarkers for early detection.

9.
Front Pharmacol ; 15: 1463339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290870

RESUMO

Background: Sress early in life has been linked to visceral hyperalgesia and associated functional gastrointestinal disorders. In a mouse model of visceral hyperalgesia, we investigated whether the EphB2 receptor and its EphrinB2 ligand in spinal cord contribute to dysregulation of glia-neuron interactions. Methods: An established mouse model of stress due to maternal separation (MS). Pups were separated from their mothers for 14 days during early development, then analyzed several weeks later in terms of visceral sensitivity based on the abdominal withdrawal reflex score and in terms of expression of c-fos, EphrinB2, EphB2, and phosphorylated MAP kinases (ERK, p38, JNK). Results: Visceral hyperalgesia due to MS upregulated EphB2, EphrinB2 and c-fos in the spinal cord, and c-fos levels positively correlated with those of EphB2 and EphrinB2. Spinal astrocytes, microglia, and neurons showed upregulation of EphB2, EphrinB2 and phosphorylated MAP kinases. Blocking EphrinB2/EphB2 signaling in MS mice reduced visceral sensitivity, activation of neurons and glia, and phosphorylation of NMDA receptor. Activating EphrinB2/EphB2 signaling in unstressed mice induced visceral hyperalgesia, upregulation of c-fos, and activation of NMDA receptor similar to maternal separation. Conclusion: The stress of MS during early development may lead to visceral hyperalgesia by upregulating EphrinB2/EphB2 in the spinal cord and thereby altering neuron-glia interactions.

10.
J Pain ; : 104686, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39321909

RESUMO

Altered nociception, a key feature of nociplastic pain, often involves central sensitization. We previously found that central sensitization underlying a nociplastic pain state in female mice depends on the ongoing activity of TRPA1 agonist-responsive afferents. Here we investigated how the activity of these afferents induces and maintains central sensitization at the spinal level. We hypothesized that in the superficial dorsal horn where somatostatin (SST) is expressed in excitatory interneurons and the SST2A receptor (SST2A-R) in GABAergic inhibitory interneurons (GABAn), TRPA1 agonist-responsive afferents stimulate SST-expressing excitatory interneurons (SSTn), leading to GABAn suppression through SST2A-R and resulting in altered nociception. We tested this hypothesis using ex vivo Ca2+ imaging of dorsal root-attached spinal cord slices expressing GCaMP6f in either SSTn or GABAn and in vivo assessment of mechanical hypersensitivity. The dorsal root was chemically (with allyl isothiocyanate, AITC) and electrically stimulated to activate TRPA1-expressing nociceptors and all afferents, respectively. The stimulation of dorsal root with AITC excited SSTn. During activation of AITC-responsive afferents, a subset of SSTn showed potentiated responses to both low- and high-threshold afferent inputs, whereas a subset of GABAn showed suppressed responses to those afferents in an SST2A-R-dependent manner. Intrathecally administered SST2A-R antagonist inhibited the development of mechanical hypersensitivity by intraplantar AITC injection and alleviated persistent mechanical hypersensitivity in the murine model of nociplastic pain. These results suggest that the activity of TRPA1 agonist-responsive afferents induces and maintains central sensitization by activating dorsal horn SSTn and suppressing GABAn via SST2A-R, resulting in altered nociception that manifests as mechanical hypersensitivity. PERSPECTIVES: This article presents experimental evidence that TRPA1 agonist-responsive afferents induce and maintain central sensitization at the spinal level by activating somatostatin (SST)-expressing excitatory interneurons and suppressing GABAergic inhibitory interneurons via SST2A receptors. Spinal SST2A-R may represent a promising target for treating mechanical pain hypersensitivity due to central sensitization by TRPA1 agonist-responsive afferents.

11.
Adv Exp Med Biol ; 1461: 199-211, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39289283

RESUMO

Body temperature is an important determinant in regulating the activities of animals. In humans, a mild 0.5 °C hyperthermia can cause headaches, demonstrating that the maintenance of normal body temperature is a key for our health. In a more extreme example, accidental acute hypothermia can lead to severe shivering, loss of consciousness, or death, although the details of these mechanisms are poorly understood. We previously found that the TRPV4 ion channel is constitutively activated by normal body temperature. The activation threshold of TRPV4 is >34 °C in the brain, which enables TRPV4 to convert thermal information into cellular signaling. Here we review the data that describe how the deletion of TRPV4 evokes abnormal behavior in mice. These studies demonstrate that the maintenance of body temperature and the sensory system for detecting body temperature, such as via TRPV4, are critical components for normal cellular function. Moreover, abnormal TRPV4 activation exacerbates cell death, epilepsy, stroke, or brain edema. Notably, TRPV4 can detect mechanical stimuli and contributes to various neural functions similar to the mechanosensitive characteristics of TRPV2. In this review, I summarize the findings related to TRPV2/TRPV4 and neural functions.


Assuntos
Encéfalo , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Encéfalo/metabolismo , Encéfalo/fisiologia , Humanos , Camundongos , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Neurônios/metabolismo
12.
Exp Neurol ; 382: 114945, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39260590

RESUMO

Mutations in the nuclear-encoded mitochondrial gene CHCHD10 have been observed in patients with a spectrum of diseases that include amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). To investigate the pathogenic nature of disease-associated variants of CHCHD10 we generated a zebrafish knock-in (KI) model expressing the orthologous ALS-associated CHCHD10P80L variant (zebrafish: Chchd10P83L). Larval chchd10P83L/P83L fish displayed reduced Chchd10 protein expression levels, motor impairment, reduced survival and abnormal neuromuscular junctions (NMJ). These deficits were not accompanied by changes in transcripts involved in the integrated stress response (ISR), phenocopying previous findings in our knockout (chchd10-/-). Adult, 11-month old chchd10P83L/P83L zebrafish, displayed smaller slow- and fast-twitch muscle cell cross-sectional areas compared to wild type zebrafish muscle cells. Motoneurons in the spinal cord of chchd10P83L/P83L zebrafish displayed similar cross-sectional areas to that of wild type motor neurons and significantly fewer motor neurons were observed when compared to chchd2-/- adult spinal cords. Bulk RNA sequencing using whole spinal cords of 7-month old fish revealed transcriptional changes associated with neuroinflammation, apoptosis, amino acid metabolism and mt-DNA inflammatory response in our chchd10P83L/P83L model. The findings presented here, suggest that the CHCHD10P80L variant confers an ALS-like phenotype when expressed in zebrafish.

13.
Ann Med ; 56(1): 2402950, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39268588

RESUMO

BACKGROUND: Aorto-ostial (AO) coronary interventions may be associated with multiple problems, including the potential embolization of atherothrombotic debris into the aorta and systemic circulation. Such embolization could theoretically lead to stroke or silent brain injury (SBI). In this study, we aimed to investigate whether there is an increased risk of SBI in patients undergoing AO stent implantation. METHODS: Fifty-five consecutive patients undergoing AO stenting and 55 consecutive patients undergoing non-AO stenting were included. Venous blood samples were obtained before and 12 h after the procedure to measure neuron-specific enolase (NSE), which is a sensitive marker of brain injury. Newly developed NSE elevation after the procedure in an asymptomatic patient was defined as SBI. RESULTS: SBI was detected in 24 (43.6%) patients in the AO stenting group and 17 (30.9%) patients in the non-AO stenting group (p = .167). Although the SBI rates were statistically comparable between the groups, the presence of significant (≥50%) AO stenosis was found to be an independent predictor of SBI in multivariate logistic regression analysis [odds ratio (OR) 2.856; 95% confidence interval (CI) 1.057-7.716; p = .038]. A longer procedure time was another independent predictor for the development of SBI (OR 1.037; 95% CI 1.005-1.069; p = .023). CONCLUSION: This study suggests that AO stenting may be associated with an increased risk of SBI if the lesion in the ostium is significant.


Assuntos
Intervenção Coronária Percutânea , Fosfopiruvato Hidratase , Stents , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Stents/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Fosfopiruvato Hidratase/sangue , Lesões Encefálicas/etiologia , Fatores de Risco , Biomarcadores/sangue
14.
Mol Ther Methods Clin Dev ; 32(3): 101312, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39257530

RESUMO

Neuroinflammation is a miscreant in accelerating progression of many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). However, treatments targeting neuroinflammation alone have led to disappointing results in clinical trials. Both neuronal and non-neuronal cell types have been implicated in the pathogenesis of ALS, and multiple studies have shown correction of each cell type has beneficial effects on disease outcome. Previously, we shown that AAV9-mediated superoxide dismutase 1 (SOD1) suppression in motor neurons and astrocytes significantly improves motor function and extends survival in ALS mouse models. Despite neuron and astrocyte correction, ALS mice still succumb to death with microgliosis observed in endpoint tissue. Therefore, we hypothesized that the optimal therapeutic approach will target and simultaneously correct motor neurons, astrocytes, and microglia. Here, we developed a novel approach to indirectly target microglia with galectin-1 (Gal1) and combined this with our previously established AAV9.SOD1.short hairpin RNA treatment. We show Gal1 conditioning of SOD1 G93A microglia decreases inflammatory markers and rescues motor neuron death in vitro. When paired with SOD1 downregulation, we found a synergistic effect of combination treatment in vivo and show a significant extension of survival of SOD1 G93A mice over SOD1 suppression alone. These results highlight the importance of targeting inflammatory microglia as a critical component in future therapeutic development.

15.
Front Neurosci ; 18: 1461178, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39280263

RESUMO

Mechanistic target of rapamycin (mTOR) plays an important role in brain development and synaptic plasticity. Dysregulation of the mTOR pathway is observed in various human central nervous system diseases, including tuberous sclerosis complex, autism spectrum disorder (ASD), and neurodegenerative diseases, including Parkinson's disease and Huntington's disease. Numerous studies focused on the effects of hyperactivation of mTOR on cortical excitatory neurons, while only a few studies focused on inhibitory neurons. Here we generated transgenic mice in which mTORC1 signaling is hyperactivated in inhibitory neurons in the striatum, while cortical neurons left unaffected. The hyperactivation of mTORC1 signaling increased GABAergic inhibitory neurons in the striatum. The transgenic mice exhibited the upregulation of dopamine receptor D1 and the downregulation of dopamine receptor D2 in medium spiny neurons in the ventral striatum. Finally, the transgenic mice demonstrated impaired motor learning and dysregulated olfactory preference behavior, though the basic function of olfaction was preserved. These findings reveal that the mTORC1 signaling pathway plays an essential role in the development and function of the striatal inhibitory neurons and suggest the critical involvement of the mTORC1 pathway in the locomotor abnormalities in neurodegenerative diseases and the sensory defects in ASD.

16.
Cureus ; 16(8): e67029, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39280534

RESUMO

This case report shows the importance of semiology during a clinical examination not only to diagnose spine clinical symptoms but also to review the central nervous system tumor as a foot drop cause. We report a unique case of a patient who consulted for constant progressive numbness and motor symptoms in the right lower extremity. Lumbar CT and MRI were negative for acute or chronic lumbar pathology. This is a 41-year-old female patient with a history of eight-month progressive right leg weakness. The physical examination did not reveal neurological alterations besides foot drop. MRI and lumbar X-rays showed no significant findings. Electromyography (EMG) indicated right peroneal neuropathy. Based on these findings, surgical treatment was not indicated; therefore, physical therapy and a referral to neurology were indicated. However, symptoms increased, resulting in a right lower extremity hemiparesis. A brain MRI showed a left frontoparietal giant meningioma, which was surgically resected after embolization. The patient evolved with a full recovery of the right-sided hemiparesis after surgery. Our case highlights the foot drop's multiple etiologies. Initially, a lumbar disc hernia was suspected, but it was ruled out by imaging studies. Later, the EMG revealed peroneal neuropathy, leading to a neurology consult. Unexpectedly, a giant intracranial meningioma was found, a rare case of foot drop. A consideration of upper motor neuron (UMN) and lower motor neuron (LMN) syndromes aided diagnosis. Tumoral resection with embolization resulted in significant improvement, showcasing the complexities of such cases. Foot drop is a peculiar clinical manifestation that must have an integral assessment to rule out peripheral and central causes. Even rare, giant meningiomas can cause focalized symptoms such as foot drop. Therefore, the assessment of foot drop should include the CT and MRI of the central nervous system.

17.
Radiol Case Rep ; 19(11): 5354-5358, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39280747

RESUMO

Schizencephaly is a highly uncommon clinical condition characterized by a diverse range of symptoms stemming from its numerous anatomical manifestations. The disorder is characterized by abnormalities in brain structure resulting from disruptions in neuronal migration. This article presents a case of schizencephaly in an Ethiopian child. The child, displaying delayed walking and speech difficulty since birth, was brought to the pediatric outpatient department for examination. The physical assessment revealed left-sided hemiparesis and an inability to sit without assistance. Subsequent magnetic resonance imaging findings confirmed the presence of open-lip schizencephaly. Therefore, neurorehabilitation, specifically highlighting the crucial importance of early intervention in enhancing cognitive and motor functions was initiated. It is imperative to acknowledge that, while a permanent cure for schizencephaly may not currently exist, neuro-rehabilitation plays a pivotal role in enhancing the overall quality of life for individuals affected by this condition.

18.
Front Cell Neurosci ; 18: 1347491, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39280793

RESUMO

Recent literature supports a prominent role for astrocytes in regulation of drug-seeking behaviors. The dorsal striatum, specifically, is known to play a role in reward processing with neuronal activity that can be influenced by astrocyte Ca2+. However, the manner in which Ca2+ in dorsal striatum astrocytes impacts neuronal signaling after exposure to self-administered cocaine remains unclear. We addressed this question following over-expression of the Ca2+ extrusion pump, hPMCA2w/b, in dorsal striatum astrocytes and the Ca2+ indicator, GCaMP6f, in dorsal striatum neurons of rats that were trained to self-administer cocaine. Following extinction of cocaine-seeking behavior, the rats over-expressing hMPCA2w/b showed a significant increase in cue-induced reinstatement of cocaine seeking. Suppression of astrocyte Ca2+ increased the amplitude of neuronal Ca2+ transients in brain slices, but only after cocaine self-administration. This was accompanied by decreased duration of neuronal Ca2+ events in the cocaine group and no changes in Ca2+ event frequency. Acute administration of cocaine to brain slices decreased amplitude of neuronal Ca2+ in both the control and cocaine self-administration groups regardless of hPMCA2w/b expression. These results indicated that astrocyte Ca2+ control over neuronal Ca2+ transients was enhanced by cocaine self-administration experience, although sensitivity to acutely applied cocaine remained comparable across all groups. To explore this further, we found that neither the hMPCA2w/b expression nor the cocaine self-administration experience altered regulation of neuronal Ca2+ events by NPS-2143, a Ca2+ sensing receptor (CaSR) antagonist, suggesting that plasticity of neuronal signaling after hPMCA2w/b over-expression was unlikely to result from elevated extracellular Ca2+. We conclude that astrocyte Ca2+ in the dorsal striatum impacts neurons via cell-intrinsic mechanisms (e.g., gliotransmission, metabolic coupling, etc.) and impacts long-term neuronal plasticity after cocaine self-administration differently from neuronal response to acute cocaine. Overall, astrocyte Ca2+ influences neuronal output in the dorsal striatum to promote resistance to cue-induced reinstatement of cocaine seeking.

19.
MethodsX ; 13: 102765, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39286440

RESUMO

Amyotrophic lateral sclerosis (ALS) characterized by progressive degeneration of motor neurons is a debilitating disease, posing substantial challenges in both prognosis and daily life assistance. However, with the advancement of machine learning (ML) which is renowned for tackling many real-world settings, it can offer unprecedented opportunities in prognostic studies and facilitate individuals with ALS in motor-imagery tasks. ML models, such as random forests (RF), have emerged as the most common and effective algorithms for predicting disease progression and survival time in ALS. The findings revealed that RF models had an excellent predictive performance for ALS, with a testing R2 of 0.524 and minimal treatment effects of 0.0717 for patient survival time. Despite significant limitations in sample size, with a maximum of 18 participants, which may not adequately reflect the population diversity being studied, ML approaches have been effectively applied to ALS datasets, and numerous prognostic models have been tested using neuroimaging data, longitudinal datasets, and core clinical variables. In many literatures, the constraints of ML models are seldom explicitly enunciated. Therefore, the main objective of this research is to provide a review of the most significant studies on the usage of ML models for analyzing ALS. This review covers a variation of ML algorithms involved in applications in ALS prognosis besides, leveraging ML to improve the efficacy of brain-computer interfaces (BCIs) for ALS individuals in later stages with restricted voluntary muscular control. The key future advances in individualized care and ALS prognosis may include the advancement of more personalized care aids that enable real-time input and ongoing validation of ML in diverse healthcare contexts.

20.
Heliyon ; 10(17): e37319, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296065

RESUMO

The organism's normal physiological function is greatly impacted in a febrile environment, leading to the manifestation of pathological conditions including elevated body temperature, dehydration, gastric bleeding, and spermatogenic dysfunction. Numerous lines of evidence indicate that heat stress significantly impacts the brain's structure and function. Previous studies have demonstrated that both animals and humans experience cognitive impairment as a result of exposure to high temperatures. However, there is a lack of research on the effects of prolonged exposure to high-temperature environments on learning and memory function, as well as the underlying molecular regulatory mechanisms. In this study, we examined the impact of long-term heat stress exposure on spatial memory function in rats and conducted transcriptome sequencing analysis of rat hippocampal tissues to identify the crucial molecular targets affected by prolonged heat stress exposure. It was found that the long-term heat stress impaired rats' spatial memory function due to the pathological damages and apoptosis of hippocampal neurons at the CA3 region, which is accompanied with the decrease of growth hormone level in peripheral blood. RNA sequencing analysis revealed the signaling pathways related to positive regulation of external stimulation response and innate immune response were dramatically affected by heat stress. Among the verified differentially expressed genes, the knockdown of Arhgap36 in neuronal cell line HT22 significantly enhances the cell apoptosis, suggesting the impaired spatial memory induced by long-term heat stress may at least partially be mediated by the dysregulation of Arhgap36 in hippocampal neurons. The uncovered relationship between molecular changes in the hippocampus and behavioral alterations induced by long-term heat stress may offer valuable insights for the development of therapeutic targets and protective drugs to enhance memory function in heat-exposed individuals.

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