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1.
Elife ; 122024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39239947

RESUMEN

Alcohol consumption in pregnancy can affect genome regulation in the developing offspring but results have been contradictory. We employed a physiologically relevant murine model of short-term moderate prenatal alcohol exposure (PAE) resembling common patterns of alcohol consumption in pregnancy in humans. Early moderate PAE was sufficient to affect site-specific DNA methylation in newborn pups without altering behavioural outcomes in adult littermates. Whole-genome bisulfite sequencing of neonatal brain and liver revealed stochastic influence on DNA methylation that was mostly tissue-specific, with some perturbations likely originating as early as gastrulation. DNA methylation differences were enriched in non-coding genomic regions with regulatory potential indicative of broad effects of alcohol on genome regulation. Replication studies in human cohorts with fetal alcohol spectrum disorder suggested some effects were metastable at genes linked to disease-relevant traits including facial morphology, intelligence, educational attainment, autism, and schizophrenia. In our murine model, a maternal diet high in folate and choline protected against some of the damaging effects of early moderate PAE on DNA methylation. Our studies demonstrate that early moderate exposure is sufficient to affect fetal genome regulation even in the absence of overt phenotypic changes and highlight a role for preventative maternal dietary interventions.


Drinking excessive amounts of alcohol during pregnancy can cause foetal alcohol spectrum disorder and other conditions in children that affect their physical and mental development. Many countries advise women who are pregnant or trying to conceive to avoid drinking alcohol entirely. However, surveys of large groups of women in Western countries indicate that most women continue drinking low to moderate amounts of alcohol until they discover they are pregnant and then stop consuming alcohol for the rest of their pregnancy. It remains unclear how this common drinking pattern affects the foetus. The instructions needed to build and maintain a human body are stored within molecules of DNA. Some regions of DNA called genes contain the instructions to make proteins, which perform many tasks in the body. Other so-called 'non-coding' regions do not code for any proteins but instead have roles in regulating gene activity. One way cells control which genes are switched on or off is adding or removing tags known as methyl groups to certain locations on DNA. Previous studies indicate that alcohol may affect how children develop by changing the patterns of methyl tags on DNA. To investigate the effect of moderate drinking during the early stages of pregnancy, Bestry et al. exposed pregnant mice to alcohol and examined how this affected the patterns of methyl tags on DNA in their offspring. The experiments found moderate levels of alcohol were sufficient to alter the patterns of methyl tags in the brains and livers of the newborn mice. Most of the changes were observed in non-coding regions of DNA, suggesting alcohol may affect how large groups of genes are regulated. Fewer changes in the patterns of methyl tags were found in mice whose mothers had diets rich in two essential nutrients known as folate and choline. Further experiments found that some of the affected mouse genes were similar to genes linked to foetal alcohol spectrum disorder and other related conditions in humans. These findings highlight the potential risks of consuming even moderate levels of alcohol during pregnancy and suggest that a maternal diet rich in folate and choline may help mitigate some of the harmful effects on the developing foetus.


Asunto(s)
Metilación de ADN , Efectos Tardíos de la Exposición Prenatal , Animales , Metilación de ADN/efectos de los fármacos , Femenino , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Ratones , Humanos , Dieta , Masculino , Etanol/efectos adversos , Etanol/toxicidad , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Encéfalo/efectos de los fármacos , Encéfalo/embriología , Encéfalo/metabolismo , Trastornos del Espectro Alcohólico Fetal/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/embriología
2.
Science ; 385(6708): adl2992, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39088624

RESUMEN

Late-onset Alzheimer's disease (LOAD) is the most common form of Alzheimer's disease (AD). However, modeling sporadic LOAD that endogenously captures hallmark neuronal pathologies such as amyloid-ß (Aß) deposition, tau tangles, and neuronal loss remains an unmet need. We demonstrate that neurons generated by microRNA (miRNA)-based direct reprogramming of fibroblasts from individuals affected by autosomal dominant AD (ADAD) and LOAD in a three-dimensional environment effectively recapitulate key neuropathological features of AD. Reprogrammed LOAD neurons exhibit Aß-dependent neurodegeneration, and treatment with ß- or γ-secretase inhibitors before (but not subsequent to) Aß deposit formation mitigated neuronal death. Moreover inhibiting age-associated retrotransposable elements in LOAD neurons reduced both Aß deposition and neurodegeneration. Our study underscores the efficacy of modeling late-onset neuropathology of LOAD through high-efficiency miRNA-based neuronal reprogramming.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Reprogramación Celular , Fibroblastos , MicroARNs , Neuronas , Esferoides Celulares , Humanos , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Secretasas de la Proteína Precursora del Amiloide/genética , Reprogramación Celular/genética , Fibroblastos/metabolismo , Fibroblastos/patología , MicroARNs/genética , MicroARNs/metabolismo , Neuronas/metabolismo , Neuronas/patología
3.
Malar J ; 23(1): 227, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090669

RESUMEN

BACKGROUND: Plasmodium falciparum, the malaria-causing parasite, is a leading cause of infection-induced deaths worldwide. The preferred treatment approach is artemisinin-based combination therapy, which couples fast-acting artemisinin derivatives with longer-acting drugs, such as lumefantrine, mefloquine, and amodiaquine. However, the urgency for new treatments has risen due to the parasite's growing resistance to existing therapies. In this study, a common characteristic of the P. falciparum proteome-stretches of poly-lysine residues, such as those found in proteins related to adhesion and pathogenicity-is investigated for its potential to treat infected erythrocytes. METHODS: This study utilizes in vitro culturing of intra-erythrocytic P. falciparum to assess the ability of poly-lysine peptides to inhibit the parasite's growth, measured via flow cytometry of acridine orange-stained infected erythrocytes. The inhibitory effect of many poly-lysine lengths and modifications were tested this way. Affinity pull-downs and mass spectrometry were performed to identify the proteins interacting with these poly-lysines. RESULTS: A single dose of these poly-basic peptides can successfully diminish parasitemia in human erythrocytes in vitro with minimal toxicity. The effectiveness of the treatment correlates with the length of the poly-lysine peptide, with 30 lysine peptides supporting the eradication of erythrocytic parasites within 72 h. PEG-ylation of the poly-lysine peptides or utilizing poly-lysine dendrimers and polymers retains or increases parasite clearance efficiency and bolsters the stability of these potential new therapeutics. Lastly, affinity pull-downs and mass-spectrometry identify P. falciparum's outer membrane proteins as likely targets for polybasic peptide medications. CONCLUSION: Since poly-lysine dendrimers are already FDA-approved for drug delivery and this study displays their potency against intraerythrocytic P. falciparum, their adaptation as anti-malarial drugs presents a promising new therapeutic strategy for malaria.


Asunto(s)
Antimaláricos , Eritrocitos , Plasmodium falciparum , Plasmodium falciparum/efectos de los fármacos , Antimaláricos/farmacología , Antimaláricos/química , Eritrocitos/efectos de los fármacos , Eritrocitos/parasitología , Péptidos/farmacología , Péptidos/química , Humanos , Polímeros/farmacología , Polímeros/química , Polilisina/farmacología , Polilisina/química
4.
Nat Commun ; 15(1): 6853, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39127720

RESUMEN

Phytochromes (Phys) are a divergent cohort of bili-proteins that detect light through reversible interconversion between dark-adapted Pr and photoactivated Pfr states. While our understandings of downstream events are emerging, it remains unclear how Phys translate light into an interpretable conformational signal. Here, we present models of both states for a dimeric Phy with histidine kinase (HK) activity from the proteobacterium Pseudomonas syringae, which were built from high-resolution cryo-EM maps (2.8-3.4-Å) of the photosensory module (PSM) and its following signaling (S) helix together with lower resolution maps for the downstream output region augmented by RoseTTAFold and AlphaFold structural predictions. The head-to-head models reveal the PSM and its photointerconversion mechanism with strong clarity, while the HK region is interpretable but relatively mobile. Pr/Pfr comparisons show that bilin phototransformation alters PSM architecture culminating in a scissoring motion of the paired S-helices linking the PSMs to the HK bidomains that ends in reorientation of the paired catalytic ATPase modules relative to the phosphoacceptor histidines. This action apparently primes autophosphorylation enroute to phosphotransfer to the cognate DNA-binding response regulator AlgB which drives quorum-sensing behavior through transient association with the photoreceptor. Collectively, these models illustrate how light absorption conformationally translates into accelerated signaling by Phy-type kinases.


Asunto(s)
Proteínas Bacterianas , Histidina Quinasa , Fitocromo , Pseudomonas syringae , Transducción de Señal , Histidina Quinasa/metabolismo , Histidina Quinasa/química , Histidina Quinasa/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Fitocromo/metabolismo , Fitocromo/química , Pseudomonas syringae/metabolismo , Modelos Moleculares , Microscopía por Crioelectrón , Conformación Proteica , Multimerización de Proteína , Fotorreceptores Microbianos/metabolismo , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/genética , Luz
5.
Dev Cell ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38942017

RESUMEN

Recent advances in human genetics have shed light on the genetic factors contributing to inflammatory diseases, particularly Crohn's disease (CD), a prominent form of inflammatory bowel disease. Certain risk genes associated with CD directly influence cytokine biology and cell-specific communication networks. Current CD therapies primarily rely on anti-inflammatory drugs, which are inconsistently effective and lack strategies for promoting epithelial restoration and mucosal balance. To understand CD's underlying mechanisms, we investigated the link between CD and the FGFR1OP gene, which encodes a centrosome protein. FGFR1OP deletion in mouse intestinal epithelial cells disrupted crypt architecture, resulting in crypt loss, inflammation, and fatality. FGFR1OP insufficiency hindered epithelial resilience during colitis. FGFR1OP was crucial for preserving non-muscle myosin II activity, ensuring the integrity of the actomyosin cytoskeleton and crypt cell adhesion. This role of FGFR1OP suggests that its deficiency in genetically predisposed individuals may reduce epithelial renewal capacity, heightening susceptibility to inflammation and disease.

6.
Ophthalmic Epidemiol ; : 1-8, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38569083

RESUMEN

PURPOSE: To describe ophthalmic findings in an Indigenous paediatric population and the associations between fetal alcohol spectrum disorder (FASD), prenatal alcohol exposure (PAE), and eye anomalies. METHODS: Medical records were reviewed for eye problems, and eye assessments were conducted by an orthoptist or ophthalmologist in the Lililwan Project cohort, which comprised 108 (81%) of all children born between 2002 and 2003, and residing in the remote Fitzroy Valley, Western Australia in 2010. Values from ophthalmic assessments and prevalence of abnormalities were presented for the total cohort and stratified by group: FASD; PAE (no FASD); and No PAE. RESULTS: Of children, 55% had PAE and 19% FASD. Most (98%) had normal vision; 15.6% had keratometry cylinder values indicating astigmatism and potential for improved vision with glasses. Strabismus (22.3%), short palpebral fissure length (PFL; 21.3%), upslanting palpebral fissures (12.0%), follicular trachomatous inflammation (6.9%), abnormal slit lamp assessments (6.7%), retinal tortuosity (6.7%), and blepharoptosis (5.6%) were identified. Strabismus and trachoma rates were higher than in the general child population. Ophthalmic findings were similar between groups except for prevalence of short PFL (FASD > No PAE; p = 0.003); abnormal keratometry cylinder values (FASD [29.4%] and PAE (no FASD) [20.0%] > No PAE [5.3%]; p = 0.031) and blepharoptosis (FASD [9.5%] > other groups [0%]; p = 0.040). CONCLUSION: Despite the small sample, some eye abnormalities were higher in children with PAE and/or FASD. Access to eye services or assessment of vision and structural eye anomalies is essential for Indigenous children, particularly those with PAE or FASD to allow early effective treatment.

7.
Nat Commun ; 15(1): 2750, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553463

RESUMEN

The defining feature of Parkinson disease (PD) and Lewy body dementia (LBD) is the accumulation of alpha-synuclein (Asyn) fibrils in Lewy bodies and Lewy neurites. Here we develop and validate a method to amplify Asyn fibrils extracted from LBD postmortem tissue samples and use solid state nuclear magnetic resonance (SSNMR) studies to determine atomic resolution structure. Amplified LBD Asyn fibrils comprise a mixture of single protofilament and two protofilament fibrils with very low twist. The protofilament fold is highly similar to the fold determined by a recent cryo-electron microscopy study for a minority population of twisted single protofilament fibrils extracted from LBD tissue. These results expand the structural characterization of LBD Asyn fibrils and approaches for studying disease mechanisms, imaging agents and therapeutics targeting Asyn.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Humanos , alfa-Sinucleína/química , Microscopía por Crioelectrón , Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/patología , Enfermedad de Parkinson/patología
8.
Cell Mol Gastroenterol Hepatol ; 17(6): 1007-1024, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38336172

RESUMEN

BACKGROUND & AIMS: In the classic form of α1-antitrypsin deficiency (ATD), the misfolded α1-antitrypsin Z (ATZ) variant accumulates in the endoplasmic reticulum (ER) of liver cells. A gain-of-function proteotoxic mechanism is responsible for chronic liver disease in a subgroup of homozygotes. Proteostatic response pathways, including conventional endoplasmic reticulum-associated degradation and autophagy, have been proposed as the mechanisms that allow cellular adaptation and presumably protection from the liver disease phenotype. Recent studies have concluded that a distinct lysosomal pathway called endoplasmic reticulum-to-lysosome completely supplants the role of the conventional macroautophagy pathway in degradation of ATZ. Here, we used several state-of-the-art approaches to characterize the proteostatic responses more fully in cellular systems that model ATD. METHODS: We used clustered regularly interspaced short palindromic repeats (CRISPR)-mediated genome editing coupled to a cell selection step by fluorescence-activated cell sorter to perform screening for proteostasis genes that regulate ATZ accumulation and combined that with selective genome editing in 2 other model systems. RESULTS: Endoplasmic reticulum-associated degradation genes are key early regulators and multiple autophagy genes, from classic as well as from ER-to-lysosome and other newly described ER-phagy pathways, participate in degradation of ATZ in a manner that is temporally regulated and evolves as ATZ accumulation persists. Time-dependent changes in gene expression are accompanied by specific ultrastructural changes including dilation of the ER, formation of globular inclusions, budding of autophagic vesicles, and alterations in the overall shape and component parts of mitochondria. CONCLUSIONS: Macroautophagy is a critical component of the proteostasis response to cellular ATZ accumulation and it becomes more important over time as ATZ synthesis continues unabated. Multiple subtypes of macroautophagy and nonautophagic lysosomal degradative pathways are needed to respond to the high concentrations of misfolded protein that characterizes ATD and these pathways are attractive candidates for genetic variants that predispose to the hepatic phenotype.


Asunto(s)
Degradación Asociada con el Retículo Endoplásmico , Retículo Endoplásmico , Lisosomas , Macroautofagia , Proteostasis , Deficiencia de alfa 1-Antitripsina , alfa 1-Antitripsina , Deficiencia de alfa 1-Antitripsina/patología , Deficiencia de alfa 1-Antitripsina/genética , Deficiencia de alfa 1-Antitripsina/metabolismo , Humanos , Lisosomas/metabolismo , alfa 1-Antitripsina/metabolismo , alfa 1-Antitripsina/genética , Retículo Endoplásmico/metabolismo , Sistemas CRISPR-Cas , Autofagia/genética , Edición Génica
9.
Nat Commun ; 15(1): 25, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167383

RESUMEN

Lipid nanodiscs have become a standard tool for studying membrane proteins, including using single particle cryo-electron microscopy (cryo-EM). We find that reconstituting the pentameric ligand-gated ion channel (pLGIC), Erwinia ligand-gated ion channel (ELIC), in different nanodiscs produces distinct structures by cryo-EM. The effect of the nanodisc on ELIC structure extends to the extracellular domain and agonist binding site. Additionally, molecular dynamic simulations indicate that nanodiscs of different size impact ELIC structure and that the nanodisc scaffold directly interacts with ELIC. These findings suggest that the nanodisc plays a crucial role in determining the structure of pLGICs, and that reconstitution of ion channels in larger nanodiscs may better approximate a lipid membrane environment.


Asunto(s)
Canales Iónicos Activados por Ligandos , Canales Iónicos Activados por Ligandos/química , Canales Iónicos Activados por Ligandos/metabolismo , Microscopía por Crioelectrón , Modelos Moleculares , Sitios de Unión , Lípidos
10.
Neuron ; 112(7): 1100-1109.e5, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38266643

RESUMEN

The Apolipoprotein E gene (APOE) is of great interest due to its role as a risk factor for late-onset Alzheimer's disease. ApoE is secreted by astrocytes in the central nervous system in high-density lipoprotein (HDL)-like lipoproteins. Structural models of lipidated ApoE of high resolution could aid in a mechanistic understanding of how ApoE functions in health and disease. Using monoclonal Fab and F(ab')2 fragments, we characterize the structure of lipidated ApoE on astrocyte-secreted lipoproteins. Our results provide support for the "double-belt" model of ApoE in nascent discoidal HDL-like lipoproteins, where two ApoE proteins wrap around the nanodisc in an antiparallel conformation. We further show that lipidated, recombinant ApoE accurately models astrocyte-secreted ApoE lipoproteins. Cryogenic electron microscopy of recombinant lipidated ApoE further supports ApoE adopting antiparallel dimers in nascent discoidal lipoproteins.


Asunto(s)
Apolipoproteínas E , Astrocitos , Lipoproteínas , Astrocitos/metabolismo , Apolipoproteínas E/genética , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Sistema Nervioso Central/metabolismo , Apolipoproteína E4/metabolismo , Apolipoproteína E3/metabolismo
11.
Nat Commun ; 14(1): 6215, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798272

RESUMEN

Homologous recombination (HR) is an essential double-stranded DNA break repair pathway. In HR, Rad52 facilitates the formation of Rad51 nucleoprotein filaments on RPA-coated ssDNA. Here, we decipher how Rad52 functions using single-particle cryo-electron microscopy and biophysical approaches. We report that Rad52 is a homodecameric ring and each subunit possesses an ordered N-terminal and disordered C-terminal half. An intrinsic structural asymmetry is observed where a few of the C-terminal halves interact with the ordered ring. We describe two conserved charged patches in the C-terminal half that harbor Rad51 and RPA interacting motifs. Interactions between these patches regulate ssDNA binding. Surprisingly, Rad51 interacts with Rad52 at two different bindings sites: one within the positive patch in the disordered C-terminus and the other in the ordered ring. We propose that these features drive Rad51 nucleation onto a single position on the DNA to promote formation of uniform pre-synaptic Rad51 filaments in HR.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Microscopía por Crioelectrón , Reparación del ADN , ADN de Cadena Simple/metabolismo , Unión Proteica , Recombinasa Rad51/metabolismo , Proteína Recombinante y Reparadora de ADN Rad52/genética , Proteína Recombinante y Reparadora de ADN Rad52/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
12.
bioRxiv ; 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37745508

RESUMEN

Plasmodium falciparum, the malaria-causing parasite, is a leading cause of infection-induced deaths worldwide. The preferred treatment approach is artemisinin-combination therapy, which couples fast-acting artemisinin derivatives with longer-acting drugs like lumefantrine, mefloquine, and amodiaquine. However, the urgency for new treatments has risen due to the parasite's growing resistance to existing therapies. Our study shows that a common characteristic of the P. falciparum proteome - stretches of poly-lysine residues such as those found in proteins related to adhesion and pathogenicity - can serve as an effective peptide treatment for infected erythrocytes. A single dose of these poly-basic peptides can successfully diminish parasitemia in human erythrocytes in vitro with minimal toxicity. The effectiveness of the treatment correlates with the length of the poly-lysine peptide, with 30 lysine peptides supporting the eradication of erythrocytic parasites within 72 hours. PEG-ylation of the poly-lysine peptides or utilizing poly-lysine dendrimers and polymers further increases parasite clearance efficiency and bolsters the stability of these potential new therapeutics. Lastly, our affinity pull-downs and mass-spectrometry identify P. falciparum's outer membrane proteins as likely targets for polybasic peptide medications. Since poly-lysine dendrimers are already FDA-approved for drug delivery, their adaptation as antimalarial drugs presents a promising new therapeutic strategy.

13.
Biol Open ; 12(7)2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37746814

RESUMEN

Intellectual disability is a neurodevelopmental disorder that affects 2-3% of the general population. Syndromic forms of intellectual disability frequently have a genetic basis and are often accompanied by additional developmental anomalies. Pathogenic variants in components of TATA-binding protein associated factors (TAFs) have recently been identified in a subset of patients with intellectual disability, craniofacial hypoplasia, and congenital heart disease. This syndrome has been termed as a TAFopathy and includes mutations in TATA binding protein (TBP), TAF1, TAF2, and TAF6. The underlying mechanism by which TAFopathies give rise to neurodevelopmental, craniofacial, and cardiac abnormalities remains to be defined. Through a forward genetic screen in zebrafish, we have recovered a recessive mutant phenotype characterized by craniofacial hypoplasia, ventricular hypoplasia, heart failure at 96 h post-fertilization and lethality, and show it is caused by a nonsense mutation in taf5. CRISPR/CAS9 mediated gene editing revealed that these defects where phenocopied by mutations in taf1 and taf5. Mechanistically, taf5-/- zebrafish displayed misregulation in metabolic gene expression and metabolism as evidenced by RNA sequencing, respiration assays, and metabolite studies. Collectively, these findings suggest that the TAF complex may contribute to neurologic, craniofacial, and cardiac development through regulation of metabolism.


Asunto(s)
Anomalías Craneofaciales , Factores Asociados con la Proteína de Unión a TATA , Proteínas de Pez Cebra , Animales , Anomalías Craneofaciales/genética , Corazón , Discapacidad Intelectual , Mutación , Factores Asociados con la Proteína de Unión a TATA/genética , Factor de Transcripción TFIID/genética , Pez Cebra , Proteínas de Pez Cebra/genética
14.
Biomed Pharmacother ; 166: 115341, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37625322

RESUMEN

Non-small-cell lung cancer (NSCLC) and glioblastoma (GB) have poor prognoses. Discovery of new molecular targets is needed to improve therapy. Tax interacting protein 1 (TIP1), which plays a role in cancer progression, is overexpressed and radiation-inducible in NSCLC and GB. We evaluated the effect of an anti-TIP1 antibody alone and in combination with ionizing radiation (XRT) on NSCLC and GB in vitro and in vivo. NSCLC and GB cells were treated with anti-TIP1 antibodies and evaluated for proliferation, colony formation, endocytosis, and cell death. The efficacy of anti-TIP1 antibodies in combination with XRT on tumor growth was measured in mouse models of NSCLC and GB. mRNA sequencing was performed to understand the molecular mechanisms involved in the action of anti-TIP1 antibodies. We found that targeting the functional domain of TIP1 leads to endocytosis of the anti-TIP1 antibody followed by reduced proliferation and increased apoptosis-mediated cell death. Anti-TIP1 antibodies bound specifically (with high affinity) to cancer cells and synergized with XRT to significantly increase cytotoxicity in vitro and reduce tumor growth in mouse models of NSCLC and GB. Importantly, downregulation of cancer survival signaling pathways was found in vitro and in vivo following treatment with anti-TIP1 antibodies. TIP1 is a new therapeutic target for cancer treatment. Antibodies targeting the functional domain of TIP1 exhibited antitumor activity and enhanced the efficacy of radiation both in vitro and in vivo. Anti-TIP1 antibodies interrupt TIP1 function and are effective cancer therapy alone or in combination with XRT in mouse models of human cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Glioblastoma , Neoplasias Pulmonares , Humanos , Animales , Ratones , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Anticuerpos/farmacología , Anticuerpos/uso terapéutico , Paclitaxel , Modelos Animales de Enfermedad
15.
Front Public Health ; 11: 1195484, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37554728

RESUMEN

Fetal alcohol spectrum disorder (FASD) continues to be underdiagnosed in Australia, partly due to the lack of trained clinicians and diagnostic services. This project aimed to help increase FASD knowledge and diagnostic capacity across Australia. Six sites across Australia formed part of a national consortium, delivering training clinics, diagnostic clinics and community education sessions. The number of FASD diagnoses significantly increased across the project. Additionally, the number of community education sessions steadily increased across the project, with largely positive feedback. Participants attending the training clinics demonstrated increased knowledge of and confidence in FASD diagnosis. This evaluation showcases the benefits of a coordinated approach to prevention, assessment, diagnosis and training in FASD.


Asunto(s)
Trastornos del Espectro Alcohólico Fetal , Femenino , Embarazo , Humanos , Trastornos del Espectro Alcohólico Fetal/diagnóstico , Australia
16.
Psychiatr Psychol Law ; 30(4): 514-535, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37484511

RESUMEN

Neurodevelopmental impairments resulting from Foetal Alcohol Spectrum Disorder (FASD) can increase the likelihood of justice system involvement. This study compared offence characteristics in young people with FASD to demographically matched controls (n = 500) in Western Australia. A novel approach (i.e. association rule mining) was adopted to uncover relationships between personal attributes and offence characteristics. For FASD participants (n = 100), file records were reviewed retrospectively. Mean age of the total sample was 15.60 years (range = 10-24), with 82% males and 88% Australian Aboriginal. After controlling for demographic factors, regression analyses showed FASD participants were more likely than controls to be charged with reckless driving (odds ratio, OR = 4.20), breach of bail/community orders (OR = 3.19), property damage (OR = 1.84), and disorderly behaviour (OR = 1.54). Overall, our findings suggest justice-involved individuals with FASD have unique offending profiles. These results have implications for sentencing, diversionary/crime prevention programs and interventions.

17.
bioRxiv ; 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37292658

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder that primarily affects elderly individuals, and is characterized by hallmark neuronal pathologies including extracellular amyloid-ß (Aß) plaque deposition, intracellular tau tangles, and neuronal death. However, recapitulating these age-associated neuronal pathologies in patient-derived neurons has remained a significant challenge, especially for late-onset AD (LOAD), the most common form of the disorder. Here, we applied the high efficiency microRNA-mediated direct neuronal reprogramming of fibroblasts from AD patients to generate cortical neurons in three-dimensional (3D) Matrigel and self-assembled neuronal spheroids. Our findings indicate that neurons and spheroids reprogrammed from both autosomal dominant AD (ADAD) and LOAD patients exhibited AD-like phenotypes linked to neurons, including extracellular Aß deposition, dystrophic neurites with hyperphosphorylated, K63-ubiquitin-positive, seed-competent tau, and spontaneous neuronal death in culture. Moreover, treatment with ß- or γ-secretase inhibitors in LOAD patient-derived neurons and spheroids before Aß deposit formation significantly lowered Aß deposition, as well as tauopathy and neurodegeneration. However, the same treatment after the cells already formed Aß deposits only had a mild effect. Additionally, inhibiting the synthesis of age-associated retrotransposable elements (RTEs) by treating LOAD neurons and spheroids with the reverse transcriptase inhibitor, lamivudine, alleviated AD neuropathology. Overall, our results demonstrate that direct neuronal reprogramming of AD patient fibroblasts in a 3D environment can capture age-related neuropathology and reflect the interplay between Aß accumulation, tau dysregulation, and neuronal death. Moreover, miRNA-based 3D neuronal conversion provides a human-relevant AD model that can be used to identify compounds that can potentially ameliorate AD-associated pathologies and neurodegeneration.

18.
Sci Transl Med ; 15(693): eade6285, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37099634

RESUMEN

Sleep loss is associated with cognitive decline in the aging population and is a risk factor for Alzheimer's disease (AD). Considering the crucial role of immunomodulating genes such as that encoding the triggering receptor expressed on myeloid cells type 2 (TREM2) in removing pathogenic amyloid-ß (Aß) plaques and regulating neurodegeneration in the brain, our aim was to investigate whether and how sleep loss influences microglial function in mice. We chronically sleep-deprived wild-type mice and the 5xFAD mouse model of cerebral amyloidosis, expressing either the humanized TREM2 common variant, the loss-of-function R47H AD-associated risk variant, or without TREM2 expression. Sleep deprivation not only enhanced TREM2-dependent Aß plaque deposition compared with 5xFAD mice with normal sleeping patterns but also induced microglial reactivity that was independent of the presence of parenchymal Aß plaques. We investigated lysosomal morphology using transmission electron microscopy and found abnormalities particularly in mice without Aß plaques and also observed lysosomal maturation impairments in a TREM2-dependent manner in both microglia and neurons, suggesting that changes in sleep modified neuro-immune cross-talk. Unbiased transcriptome and proteome profiling provided mechanistic insights into functional pathways triggered by sleep deprivation that were unique to TREM2 and Aß pathology and that converged on metabolic dyshomeostasis. Our findings highlight that sleep deprivation directly affects microglial reactivity, for which TREM2 is required, by altering the metabolic ability to cope with the energy demands of prolonged wakefulness, leading to further Aß deposition, and underlines the importance of sleep modulation as a promising future therapeutic approach.


Asunto(s)
Enfermedad de Alzheimer , Amiloidosis , Ratones , Animales , Microglía/metabolismo , Privación de Sueño/complicaciones , Privación de Sueño/metabolismo , Privación de Sueño/patología , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/patología , Encéfalo/metabolismo , Placa Amiloide/patología , Modelos Animales de Enfermedad , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos/metabolismo
19.
Nat Commun ; 14(1): 1712, 2023 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-36973289

RESUMEN

The pannexin 2 channel (PANX2) participates in multiple physiological processes including skin homeostasis, neuronal development, and ischemia-induced brain injury. However, the molecular basis of PANX2 channel function remains largely unknown. Here, we present a cryo-electron microscopy structure of human PANX2, which reveals pore properties contrasting with those of the intensely studied paralog PANX1. The extracellular selectivity filter, defined by a ring of basic residues, more closely resembles that of the distantly related volume-regulated anion channel (VRAC) LRRC8A, rather than PANX1. Furthermore, we show that PANX2 displays a similar anion permeability sequence as VRAC, and that PANX2 channel activity is inhibited by a commonly used VRAC inhibitor, DCPIB. Thus, the shared channel properties between PANX2 and VRAC may complicate dissection of their cellular functions through pharmacological manipulation. Collectively, our structural and functional analysis provides a framework for development of PANX2-specific reagents that are needed for better understanding of channel physiology and pathophysiology.


Asunto(s)
Conexinas , Proteínas de la Membrana , Proteínas del Tejido Nervioso , Humanos , Aniones , Transporte Biológico , Conexinas/metabolismo , Microscopía por Crioelectrón , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo
20.
Cell Rep ; 42(4): 112293, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36952346

RESUMEN

Demyelination is a hallmark of multiple sclerosis, leukoencephalopathies, cerebral vasculopathies, and several neurodegenerative diseases. The cuprizone mouse model is widely used to simulate demyelination and remyelination occurring in these diseases. Here, we present a high-resolution single-nucleus RNA sequencing (snRNA-seq) analysis of gene expression changes across all brain cells in this model. We define demyelination-associated oligodendrocytes (DOLs) and remyelination-associated MAFBhi microglia, as well as astrocytes and vascular cells with signatures of altered metabolism, oxidative stress, and interferon response. Furthermore, snRNA-seq provides insights into how brain cell types connect and interact, defining complex circuitries that impact demyelination and remyelination. As an explicative example, perturbation of microglia caused by TREM2 deficiency indirectly impairs the induction of DOLs. Altogether, this study provides a rich resource for future studies investigating mechanisms underlying demyelinating diseases.


Asunto(s)
Enfermedades Desmielinizantes , Remielinización , Animales , Ratones , Enfermedades Desmielinizantes/metabolismo , Transcriptoma/genética , Encéfalo/metabolismo , Oligodendroglía/metabolismo , Microglía/metabolismo , Cuprizona/toxicidad , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Vaina de Mielina/metabolismo
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