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1.
Cell ; 184(5): 1142-1155, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33667368

RESUMO

The characterization of cancer genomes has provided insight into somatically altered genes across tumors, transformed our understanding of cancer biology, and enabled tailoring of therapeutic strategies. However, the function of most cancer alleles remains mysterious, and many cancer features transcend their genomes. Consequently, tumor genomic characterization does not influence therapy for most patients. Approaches to understand the function and circuitry of cancer genes provide complementary approaches to elucidate both oncogene and non-oncogene dependencies. Emerging work indicates that the diversity of therapeutic targets engendered by non-oncogene dependencies is much larger than the list of recurrently mutated genes. Here we describe a framework for this expanded list of cancer targets, providing novel opportunities for clinical translation.


Assuntos
Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Animais , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Genômica , Humanos , Neoplasias/genética , Neoplasias/patologia , Evasão Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
2.
Neurobiol Dis ; 191: 106411, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38228253

RESUMO

Parkinson's disease (PD) pathology is characterized by alpha-synuclein (α-syn) aggregates, degeneration of dopamine neurons in the substantia nigra pars compacta (SNpc), and neuroinflammation. The presence of reactive glia correlates with deposition of pathological α-syn in early-stage PD. Thus, understanding the neuroinflammatory response of microglia and astrocytes to synucleinopathy may identify therapeutic targets. Here we characterized the neuroinflammatory gene expression profile of reactive microglia and astrocytes in the SNpc during early synucleinopathy in the rat α-syn pre-formed fibril (PFF) model. Rats received intrastriatal injection of α-syn PFFs and expression of immune genes was quantified with droplet digital PCR (ddPCR), after which fluorescent in situ hybridization (FISH) was used to localize gene expression to microglia or astrocytes in the SNpc. Genes previously associated with reactive microglia (Cd74, C1qa, Stat1, Axl, Casp1, Il18, Lyz2) and reactive astrocytes (C3, Gbp2, Serping1) were significantly upregulated in the SN of PFF injected rats. Localization of gene expression to SNpc microglia near α-syn aggregates identified a unique α-syn aggregate microglial gene expression profile characterized by upregulation of Cd74, Cxcl10, Rt-1a2, Grn, Csf1r, Tyrobp, C3, C1qa, Serping1 and Fcer1g. Importantly, significant microglial upregulation of Cd74 and C3 were only observed following injection of α-syn PFFs, not α-syn monomer, confirming specificity to α-syn aggregation. Serping1 expression also localized to astrocytes in the SNpc. Interestingly, C3 expression in the SNpc localized to microglia at 2- and 4-months post-PFF, but to astrocytes at 6-months post-PFF. We also observed expression of Rt1-a2 and Cxcl10 in SNpc dopamine neurons. Cumulatively our results identify a dynamic, yet reproducible gene expression profile of reactive microglia and astrocytes associated with early synucleinopathy in the rat SNpc.


Assuntos
Doença de Parkinson , Sinucleinopatias , Animais , Ratos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Proteína Inibidora do Complemento C1/genética , Proteína Inibidora do Complemento C1/metabolismo , Neurônios Dopaminérgicos/metabolismo , Hibridização in Situ Fluorescente , Neuroglia/metabolismo , Doenças Neuroinflamatórias , Doença de Parkinson/metabolismo , Substância Negra/metabolismo , Sinucleinopatias/patologia , Transcriptoma
3.
Eur J Neurosci ; 59(7): 1585-1603, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38356120

RESUMO

Parkinson's disease (PD) is characterized by the accumulation of misfolded alpha-synuclein (α-syn) protein, forming intraneuronal Lewy body (LB) inclusions. The α-syn preformed fibril (PFF) model of PD recapitulates α-syn aggregation, progressive nigrostriatal degeneration and motor dysfunction; however, little is known about the time course of PFF-induced alterations in basal and evoked dopamine (DA). In vivo microdialysis is well suited for identifying small changes in neurotransmitter levels over extended periods. In the present study, adult male Fischer 344 rats received unilateral, intrastriatal injections of either α-syn PFFs or phosphate-buffered saline (PBS). At 4 or 8 months post-injection (p.i.), animals underwent in vivo microdialysis to evaluate basal extracellular striatal DA and metabolite levels, local KCl-evoked striatal DA release and the effects of systemic levodopa (l-DOPA). Post-mortem analysis demonstrated equivalent PFF-induced reductions in tyrosine hydroxylase (TH) immunoreactive nigral neurons (~50%) and striatal TH (~20%) at both time points. Compared with reduction in striatal TH, reduction in striatal dopamine transporter (DAT) was more pronounced and progressed between the 4- and 8-month p.i. intervals (36% âž” 46%). Significant PFF-induced deficits in basal and evoked striatal DA, as well as deficits in motor performance, were not observed until 8 months p.i. Responses to l-DOPA did not differ regardless of PBS or PFF treatment. These results suggest that basal and evoked striatal DA are maintained for several months following PFF injection, with loss of both associated with motor dysfunction. Our studies provide insight into the time course and magnitude of PFF-induced extracellular dopaminergic deficits in the striatum.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Ratos , Masculino , Animais , alfa-Sinucleína/metabolismo , Dopamina/metabolismo , Levodopa/farmacologia , Microdiálise , Substância Negra/metabolismo , Doença de Parkinson/metabolismo
4.
J Neuroinflammation ; 21(1): 108, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664840

RESUMO

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder that is characterized by the presence of proteinaceous alpha-synuclein (α-syn) inclusions (Lewy bodies), markers of neuroinflammation and the progressive loss of nigrostriatal dopamine (DA) neurons. These pathological features can be recapitulated in vivo using the α-syn preformed fibril (PFF) model of synucleinopathy. We have previously determined that microglia proximal to PFF-induced nigral α-syn inclusions increase in soma size, upregulate major-histocompatibility complex-II (MHC-II) expression, and increase expression of a suite of inflammation-associated transcripts. This microglial response is observed months prior to degeneration, suggesting that microglia reacting to α-syn inclusion may contribute to neurodegeneration and could represent a potential target for novel therapeutics. The goal of this study was to determine whether colony stimulating factor-1 receptor (CSF1R)-mediated microglial depletion impacts the magnitude of α-syn aggregation, nigrostriatal degeneration, or the response of microglial in the context of the α-syn PFF model. METHODS: Male Fischer 344 rats were injected intrastriatally with either α-syn PFFs or saline. Rats were continuously administered Pexidartinib (PLX3397B, 600 mg/kg), a CSF1R inhibitor, to deplete microglia for a period of either 2 or 6 months. RESULTS: CSF1R inhibition resulted in significant depletion (~ 43%) of ionized calcium-binding adapter molecule 1 immunoreactive (Iba-1ir) microglia within the SNpc. However, CSF1R inhibition did not impact the increase in microglial number, soma size, number of MHC-II immunoreactive microglia or microglial expression of Cd74, Cxcl10, Rt-1a2, Grn, Csf1r, Tyrobp, and Fcer1g associated with phosphorylated α-syn (pSyn) nigral inclusions. Further, accumulation of pSyn and degeneration of nigral neurons was not impacted by CSF1R inhibition. Paradoxically, long term CSF1R inhibition resulted in increased soma size of remaining Iba-1ir microglia in both control and PFF rats, as well as expression of MHC-II in extranigral regions. CONCLUSIONS: Collectively, our results suggest that CSF1R inhibition does not impact the microglial response to nigral pSyn inclusions and that CSF1R inhibition is not a viable disease-modifying strategy for PD.


Assuntos
Microglia , Ratos Endogâmicos F344 , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , alfa-Sinucleína , Animais , Microglia/metabolismo , Microglia/efeitos dos fármacos , alfa-Sinucleína/metabolismo , Ratos , Masculino , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Pirróis/farmacologia , Aminopiridinas/farmacologia , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Substância Negra/metabolismo , Substância Negra/patologia , Substância Negra/efeitos dos fármacos , Modelos Animais de Doenças
5.
J Pharmacol Exp Ther ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866563

RESUMO

Mutations in the GNAO1 gene, which encodes the abundant brain G-protein Gαo, result in neurologic disorders characterized by developmental delay, epilepsy, and movement abnormalities. There are over 50 mutant alleles associated with GNAO1 disorders; the R209H mutation results in dystonia, choreoathetosis, and developmental delay without seizures. Mice heterozygous for the human mutant allele (Gnao1 +/R209H) exhibit hyperactivity in open field tests but no seizures. We developed self-complimentary adeno-associated virus vectors (scAAV9) expressing two splice variants of human GNAO1 Gαo isoforms 1 (GoA, GNAO1.1) and 2 (GoB, GNAO1.2). Bilateral intra-striatal injections of either scAAV9-GNAO1.1 or scAAV9-GNAO1.2 significantly reversed mutation-associated hyperactivity in open field tests. GNAO1 overexpression did not increase seizure susceptibility, a potential side-effect of GNAO1 vector treatment. This represents the first report of successful preclinical gene therapy for GNAO1 encephalopathy applied in vivo Further studies are needed to uncover the molecular mechanism that results in behavior improvements after scAAV9-mediated Gαo expression and to refine the vector design. Significance Statement GNAO1 mutations cause a spectrum of developmental, epilepsy, and movement disorders. Here, we show that intra-striatal delivery of scAAV9-GNAO1 to express the wild-type Gαo protein reduces the hyperactivity of the Gnao1 +/R209H mouse model, which carries one of the most common movement disorder-associated mutations. This is the first report of a gene therapy for GNAO1 encephalopathy applied in vivo on a patient-allele model.

8.
Matern Child Nutr ; : e13658, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704754

RESUMO

Limited evidence exists on the costs of scaled-up multisectoral nutrition programmes. Such evidence is crucial to assess intervention value and affordability. Evidence is also lacking on the opportunity costs of implementers and participants engaging in community-level interventions. We help to fill this gap by estimating the full financial and economic costs of the United States Agency for International Development-funded Suaahara II (SII) programme, a scaled-up multisectoral nutrition programme in Nepal (2016-2023). We applied a standardized mixed methods costing approach to estimate total and unit costs over a 3.7-year implementation period. Financial expenditure data from national and subnational levels were combined with economic cost estimates assessed using in-depth interviews and focus group discussions with staff, volunteers, community members, and government partners in four representative districts. The average annual total cost was US$908,948 per district, with economic costs accounting for 47% of the costs. The annual unit cost was US$132 per programme participant (mother in the 1000-day period between conception and a child's second birthday) reached. Annual costs ranged from US$152 (mountains) to US$118 (plains) per programme participant. Personnel (63%) were the largest input cost driver, followed by supplies (11%). Community events (29%) and household counselling visits (17%) were the largest activity cost drivers. Volunteer cadres contributed significant time to the programme, with female community health volunteers spending a substantial amount of time (27 h per month) on SII activities. Multisectoral nutrition programmes can be costly, especially when taking into consideration volunteer and participant opportunity costs. This study provides much-needed evidence of the costs of scaled-up multisectoral nutrition programmes for future comparison against benefits.

9.
AIDS Behav ; 27(3): 783-795, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36210392

RESUMO

Depression is common during pregnancy and is associated with reduced adherence to HIV-related care, though little is known about perinatal trajectories of depression and viral suppression among women living with HIV (WLHV) in sub-Saharan Africa. We sought to assess any association between perinatal depressive symptoms and viral non-suppression among WLWH. Depressive symptomatology and viral load data were collected every 6 months from WLWH enrolled in the African Cohort Study (AFRICOS; January 2013-February 2020). Generalized estimating equations modeled associations between depressive symptoms [Center for Epidemiological Studies Depression (CES-D) ≥ 16] and viral non-suppression. Of 1722 WLWH, 248 (14.4%) had at least one pregnancy (291 total) and for 61 pregnancies (21.0%), women reported depressive symptoms (13.4% pre-conception, 7.6% pregnancy, 5.5% one-year postpartum). Depressive symptomatology was associated with increased odds of viral non-suppression (aOR 2.2; 95% CI 1.2-4.0, p = 0.011). Identification and treatment of depression among women with HIV may improve HIV outcomes for mothers.


Assuntos
Infecções por HIV , Gestantes , Gravidez , Feminino , Humanos , Depressão , Estudos de Coortes , Estudos Prospectivos , Uganda , Quênia , Nigéria , Tanzânia
10.
Prev Sci ; 24(Suppl 2): 283-291, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37227589

RESUMO

Respecting the Circle of Life (RCL) is a teen pregnancy prevention program that was evaluated for effectiveness on sexual health risk behaviors through a two-arm randomized control trial (RCT) with American Indian (AI) youth ages 11-19. The objective of this study is to investigate the effects of RCL compared to a control group on items of condom and contraception self-efficacy. Linear regression analysis was used to compare differences in each item that included condom and contraception self-efficacy scales among the intervention and control participants at baseline, 3 and 9 months post intervention. Youth enrolled in the intervention reported higher levels of condom and contraception self-efficacy across almost all individual items. Exceptions include items related to partner negotiation of condom self-efficacy at 3 months (p = 0.227) and 9 months (p = 0.074) post intervention. Findings indicate RCL is effective at improving overall condom and contraception self-efficacy but did not impact the specific component of partner negotiation for either condom or contraception self-efficacy. This inquiry provides rationale to further explore components of RCL related to partner negotiation.


Assuntos
Indígena Americano ou Nativo do Alasca , Preservativos , Comportamento Contraceptivo , Autoeficácia , Adolescente , Feminino , Humanos , Gravidez , Anticoncepção , Conhecimentos, Atitudes e Prática em Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Comportamento Sexual , Criança , Adulto Jovem
11.
Prev Sci ; 24(Suppl 2): 229-240, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37191932

RESUMO

In 2019, Native youth had the highest rate of teen pregnancy of all racial/ethnic groups. "Respecting the Circle of Life" (RCL) is one of the first evidence-based teen pregnancy prevention programs for Native teens and there is interest in replicating the program across tribal communities. To inform replication, it is important to consider process data including quality, fidelity, and dosage as these may all moderate impact of the program. Participants were Native youth aged 11-19 and a trusted adult. This study includes participants randomized to the RCL program only (N = 266). Data sources include independent observations, facilitator self-assessments, attendance logs, and self-report assessments completed by enrolled youth at baseline and 3 months post assessment. Data was compiled and summed by cohort. Dosage was number of minutes participating in activities separated by theoretical constructs. Linear regression models were utilized to assess moderation of the effects of the intervention dosage on outcomes of interest. Eighteen facilitators delivered RCL. One hundred eighteen independent observations and 320 facilitator self-assessments were collected and entered. Findings indicate RCL was implemented with high fidelity and quality (4.40 to 4.82 out of a 5-point Likert scale; 96.6% of planned activities completed). Dosage was high with an average completion of 7 out of 9 lessons. There was no association between theoretical construct dosage and outcomes of interest. Overall, this study indicates RCL was delivered with high fidelity, quality, and dosage in this trial. This paper informs future replication of RCL and provides support for hiring paraprofessionals from the local community as facilitators, delivering the RCL to peer groups of the same age and sex, delivering the RCL with short duration and high frequency, and encouraging youth to attend all RCL lessons, but continue to serve youth who have missed one or more lessons.


Assuntos
Comportamento do Adolescente , Indígenas Norte-Americanos , Gravidez na Adolescência , Adolescente , Feminino , Humanos , Gravidez , Gravidez na Adolescência/prevenção & controle , Educação Sexual , Criança , Adulto Jovem
12.
J Neurosci ; 41(9): 2039-2052, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33472823

RESUMO

Preclinical studies show a link between subthalamic nucleus (STN) deep brain stimulation (DBS) and neuroprotection of nigrostriatal dopamine (DA) neurons, potentially through brain-derived neurotrophic factor (BDNF) signaling. However, the question of whether DBS of the STN can be disease-modifying in Parkinson's disease (PD) remains unanswered. In particular, the impact of STN DBS on α-synuclein (α-syn) aggregation, inclusion-associated neuroinflammation, and BDNF levels has yet to be examined in the context of synucleinopathy. To address this, we examined the effects of STN DBS on BDNF using the α-syn preformed fibril (PFF) model in male rats. While PFF injection resulted in accumulation of phosphorylated α-syn (pSyn) inclusions in the substantia nigra pars compacta (SNpc) and cortical areas, STN DBS did not impact PFF-induced accumulation of pSyn inclusions in the SNpc. In addition, nigral pSyn inclusions were associated with increased microgliosis and astrogliosis; however, the magnitude of these processes was not altered by STN DBS. Total BDNF protein was not impacted by pSyn inclusions, but the normally positive association of nigrostriatal and corticostriatal BDNF was reversed in rats with PFF-induced nigrostriatal and corticostriatal inclusions. Despite this, rats receiving both STN DBS and PFF injection showed increased BDNF protein in the striatum, which partially restored the normal corticostriatal relationship. Our results suggest that pathologic α-syn inclusions disrupt anterograde BDNF transport within nigrostriatal and corticostriatal circuitry. Further, STN DBS has the potential to exert protective effects by modifying the long-term neurodegenerative consequences of synucleinopathy.SIGNIFICANCE STATEMENT An increase in brain-derived neurotrophic factor (BDNF) has been linked to the neuroprotection elicited by subthalamic nucleus (STN) deep brain stimulation (DBS) in neurotoxicant models of Parkinson's disease (PD). However, whether STN DBS can similarly increase BDNF in nigrostriatal and corticostriatal circuitry in the presence of α-synuclein (α-syn) inclusions has not been examined. We examined the impact of STN DBS on rats in which accumulation of α-syn inclusions is induced by injection of α-syn preformed fibrils (PFFs). STN DBS significantly increased striatal BDNF protein in rats seeded with α-syn inclusions and partially restored the normal corticostriatal BDNF relationship. These findings suggest that STN DBS can drive BDNF in the parkinsonian brain and retains the potential for neuroprotection in PD.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Estimulação Encefálica Profunda , Parte Compacta da Substância Negra/metabolismo , Parte Compacta da Substância Negra/patologia , Sinucleinopatias/metabolismo , Sinucleinopatias/patologia , Animais , Modelos Animais de Doenças , Masculino , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ratos , Ratos Endogâmicos F344 , Núcleo Subtalâmico/fisiologia
13.
Mov Disord ; 37(8): 1739-1748, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35524682

RESUMO

BACKGROUND: Positron emission tomography (PET) imaging in early Parkinson's disease (PD) subjects reveals that increased dopamine (DA) turnover and reduced dopamine transporter (DAT) density precede decreases in DA synthesis and storage. The rat α-synuclein preformed fibril (α-syn PFF) model provides a platform to investigate DA dynamics during multiple stages of α-syn inclusion-triggered nigrostriatal degeneration. OBJECTIVES: We investigated multiple aspects of in vivo dopaminergic deficits longitudinally and similarities to human PD using translational PET imaging readouts. METHODS: Longitudinal imaging was performed every 2 months in PFF and control rats for 7 months. [18 F]-Fluoro-3,4-dihydroxyphenyl-L-alanine (FDOPA) imaging was performed to investigate DA synthesis and storage (Kocc ) and DA turnover, estimated by its inverse, the effective distribution volume ratio (EDVR). 11 C-Methylphenidate (MP) was used to estimate DAT density (BPND ). RESULTS: Early DA turnover increases and DAT binding decreases were observed in the ipsilateral striatum of PFF rats, progressing longitudinally. EDVR decreased 26%, 38%, and 47%, and BPND decreased 36%, 50%, and 65% at the 2-, 4-, and 6-month time points, respectively, compared to ipsilateral control striatum. In contrast, deficits in DA synthesis and storage were not observed in the ipsilateral striatum of PFF rats compared to control injections and were relatively preserved up to 6 months (Kocc decreased 20% at 6 months). CONCLUSIONS: The relative preservation of DA synthesis and storage compared to robust progressive deficits in DAT density and increases in DA turnover in the rat α-syn PFF model display remarkable face validity to dopaminergic alterations in human PD. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons , Ratos , alfa-Sinucleína/metabolismo
14.
Matern Child Nutr ; 18(2): e13323, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35137531

RESUMO

Economic evaluation of nutrition interventions that compares the costs to benefits is essential to priority-setting. However, there are unique challenges to synthesizing the findings of multi-sectoral nutrition interventions due to the diversity of potential benefits and the methodological differences among sectors in measuring them. This systematic review summarises literature on the interventions, sectors, benefit terminology and benefit types included in cost-effectiveness, cost-utility and benefit-cost analyses (CEA, CUA and BCA, respectively) of nutrition interventions in low- and middle-income countries. A systematic search of five databases published from January 2010 to September 2019 with expert consultation yielded 2794 studies, of which 93 met all inclusion criteria. Eighty-seven per cent of the included studies included interventions delivered from only one sector, with almost half from the health sector (43%), followed by food/agriculture (27%), water, sanitation and hygiene (WASH) (10%), and social protection (8%). Only 9% of studies assessed programmes involving more than one sector (health, food/agriculture, social protection and/or WASH). Eighty-one per cent of studies used more than one term to refer to intervention benefits. The included studies calculated 128 economic evaluation ratios (57 CEAs, 39 CUAs and 32 BCAs), and the benefits they included varied by sector. Nearly 60% measured a single benefit category, most frequently nutritional status improvements; other health benefits, cognitive/education gains, dietary diversity, food security, knowledge/attitudes/practices and income were included in less than 10% of all ratios. Additional economic evaluation of non-health and multi-sector interventions, and incorporation of benefits beyond nutritional improvements (including cost savings) in future economic evaluations is recommended.


Assuntos
Países em Desenvolvimento , Renda , Análise Custo-Benefício , Humanos , Estado Nutricional , Saneamento
15.
Nature ; 517(7535): 489-92, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25363767

RESUMO

Next-generation sequencing of human tumours has refined our understanding of the mutational processes operative in cancer initiation and progression, yet major questions remain regarding the factors that induce driver mutations and the processes that shape mutation selection during tumorigenesis. Here we performed whole-exome sequencing on adenomas from three mouse models of non-small-cell lung cancer, which were induced either by exposure to carcinogens (methyl-nitrosourea (MNU) and urethane) or by genetic activation of Kras (Kras(LA2)). Although the MNU-induced tumours carried exactly the same initiating mutation in Kras as seen in the Kras(LA2) model (G12D), MNU tumours had an average of 192 non-synonymous, somatic single-nucleotide variants, compared with only six in tumours from the Kras(LA2) model. By contrast, the Kras(LA2) tumours exhibited a significantly higher level of aneuploidy and copy number alterations compared with the carcinogen-induced tumours, suggesting that carcinogen-induced and genetically engineered models lead to tumour development through different routes. The wild-type allele of Kras has been shown to act as a tumour suppressor in mouse models of non-small-cell lung cancer. We demonstrate that urethane-induced tumours from wild-type mice carry mostly (94%) Kras Q61R mutations, whereas those from Kras heterozygous animals carry mostly (92%) Kras Q61L mutations, indicating a major role for germline Kras status in mutation selection during initiation. The exome-wide mutation spectra in carcinogen-induced tumours overwhelmingly display signatures of the initiating carcinogen, while adenocarcinomas acquire additional C > T mutations at CpG sites. These data provide a basis for understanding results from human tumour genome sequencing, which has identified two broad categories of tumours based on the relative frequency of single-nucleotide variations and copy number alterations, and underline the importance of carcinogen models for understanding the complex mutation spectra seen in human cancers.


Assuntos
Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Genes ras/genética , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Mutação/genética , Proteína Oncogênica p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/genética , Animais , Carcinógenos/toxicidade , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/genética , Variações do Número de Cópias de DNA/genética , Progressão da Doença , Feminino , Instabilidade Genômica/genética , Mutação em Linhagem Germinativa/genética , Humanos , Masculino , Metilnitrosoureia/toxicidade , Camundongos , Modelos Genéticos , Mutação Puntual/genética , Uretana/toxicidade
16.
Neurobiol Dis ; 141: 104947, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32422283

RESUMO

Human and animal studies have shown that exposure to the organochlorine pesticide dieldrin is associated with increased risk of Parkinson's disease (PD). Previous work showed that developmental dieldrin exposure increased neuronal susceptibility to MPTP toxicity in male C57BL/6 mice, possibly via changes in dopamine (DA) packaging and turnover. However, the relevance of the MPTP model to PD pathophysiology has been questioned. We therefore studied dieldrin-induced neurotoxicity in the α-synuclein (α-syn)-preformed fibril (PFF) model, which better reflects the α-syn pathology and toxicity observed in PD pathogenesis. Specifically, we used a "two-hit" model to determine whether developmental dieldrin exposure increases susceptibility to α-syn PFF-induced synucleinopathy. Dams were fed either dieldrin (0.3 mg/kg, every 3-4 days) or vehicle corn oil starting 1 month prior to breeding and continuing through weaning of pups at postnatal day 22. At 12 weeks of age, male and female offspring received intrastriatal α-syn PFF or control saline injections. Consistent with the male-specific increased susceptibility to MPTP, our results demonstrate that developmental dieldrin exposure exacerbates PFF-induced toxicity in male mice only. Specifically, in male offspring, dieldrin exacerbated PFF-induced motor deficits on the challenging beam and increased DA turnover in the striatum 6 months after PFF injection. However, male offspring showed neither exacerbation of phosphorylated α-syn aggregation (pSyn) in the substantia nigra (SN) at 1 or 2 months post-PFF injection, nor exacerbation of PFF-induced TH and NeuN loss in the SN 6 months post-PFF injection. Collectively, these data indicate that developmental dieldrin exposure produces a male-specific exacerbation of synucleinopathy-induced behavioral and biochemical deficits. This sex-specific result is consistent with both previous work in the MPTP model, our previously reported sex-specific effects of this exposure paradigm on the male and female epigenome, and the higher prevalence and more severe course of PD in males. The novel two-hit environmental toxicant/PFF exposure paradigm established in this project can be used to explore the mechanisms by which other PD-related exposures alter neuronal vulnerability to synucleinopathy in sporadic PD.


Assuntos
Dieldrin/toxicidade , Atividade Motora/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Praguicidas/toxicidade , Agregação Patológica de Proteínas , alfa-Sinucleína/toxicidade , Animais , Dopamina/metabolismo , Feminino , Masculino , Camundongos Endogâmicos C57BL , Agregação Patológica de Proteínas/induzido quimicamente , Agregação Patológica de Proteínas/metabolismo , Fatores Sexuais , Substância Negra/metabolismo , Substância Negra/patologia , alfa-Sinucleína/administração & dosagem
17.
Prostate ; 80(7): 588-605, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32162714

RESUMO

BACKGROUND: The prostate-specific phosphatase and tensin homolog deleted on chromosome 10 (Pten) gene-conditional knockout (KO) mouse carcinogenesis model is highly desirable for studies of prostate cancer biology and chemoprevention due to its close resemblance of primary molecular defect and many histopathological features of human prostate cancer including androgen response and disease progression from prostatic intraepithelial neoplasia to invasive adenocarcinoma. Here, we profiled the proteome and transcriptome of the Pten-KO mouse prostate tumors for global macromolecular expression alterations for signaling changes and biomarker signatures. METHODS: For proteomics, four pairs of whole prostates from tissue-specific conditional knockout Pten-KO mice (12-15 weeks of age) and their respective wild-type littermates housed in the same cages were analyzed by 8-plex isobaric tags for relative and absolute quantitation iTRAQ. For microarray transcriptomic analysis, three additional matched pairs of prostate/tumor specimens from respective mice at 20 to 22 weeks of age were used. Real-time quantitative reverse transcription-polymerase chain reaction was used to verify the trends of protein and RNA expression changes. Gene Set Enrichment Analysis and Ingenuity Pathway Analysis were carried out for bioinformatic characterizations of pathways and networks. RESULTS: At the macromolecular level, proteomic and transcriptomic analyses complement and cross-validate to reveal overexpression signatures including inflammation and immune alterations, in particular, neutrophil/myeloid lineage suppressor cell features, chromatin/histones, ion and nutrient transporters, and select glutathione peroxidases and transferases in Pten-KO prostate tumors. Suppressed expression patterns in the Pten-KO prostate tumors included glandular differentiation such as secretory proteins and androgen receptor targets, smooth muscle features, and endoplasmic reticulum stress proteins. Bioinformatic analyses identified immune and inflammation responses as the most profound macromolecular landscape changes, and the predicted key nodal activities through Akt, nuclear factor-kappaB, and P53 in the Pten-KO prostate tumor. Comparison with other genetically modified mouse prostate carcinogenesis models revealed notable molecular distinctions, especially the dominance of immune and inflammation features in the Pten-KO prostate tumors. CONCLUSIONS: Our work identified prominent macromolecular signatures and key nodal molecules that help to illuminate the patho- and immunobiology of Pten-loss driven prostate cancer and can facilitate the choice of biomarkers for chemoprevention and interception studies in this clinically relevant mouse prostate cancer model.


Assuntos
PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , PTEN Fosfo-Hidrolase/deficiência , Neoplasias da Próstata/patologia , Proteômica
18.
AIDS Behav ; 24(6): 1727-1742, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31673913

RESUMO

Antiretroviral therapy (ART) is efficacious in improving clinical outcomes among people living with HIV (PLWH) and reducing HIV transmission when taken regularly. Research examining modifiable factors associated with ART non-adherence is critical for informing novel intervention development in settings with high HIV prevalence. Alcohol use has been linked with ART non-adherence in studies in sub-Saharan Africa; however, no review has pooled estimates across studies. We reviewed studies of alcohol use and ART non-adherence conducted in sub-Saharan Africa. We searched PubMed, CINAHL, EMBASE, and PsycINFO through August 2019 with terms related to ART non-adherence, alcohol use, and sub-Saharan Africa. One author reviewed titles/abstracts (n = 754) and two authors reviewed full texts (n = 308) for inclusion. Discrepancies were resolved by group consensus. Studies were retained if they quantitatively measured associations between alcohol use and ART non-adherence or viral non-suppression. We defined ART non-adherence using the definitions from each parent study (e.g., patients with > 5% missed ART doses during the previous four, seven or 30 days were considered non-adherent). A random effects meta-analysis was conducted to pool associations and we conducted additional analyses to assess between-study heterogeneity and publication bias and sensitivity analyses to determine robustness of our results when considering only certain study designs, alcohol use or ART scales, or studies that used viral non-suppression as their primary outcome. Of 56 articles meeting our inclusion criteria, 32 articles were included in the meta-analysis. All studies measured alcohol use via self-report. ART non-adherence was assessed using self-report, pill counts, or pharmacy records and definition of non-adherence varied depending on the measure used. Individuals who used alcohol had twice the odds of ART non-adherence compared with those who did not use alcohol (34% non-adherence among alcohol users vs. 18% among non-users; pooled odds ratio: 2.25; 95% confidence interval: 1.87-2.69; p < 0.001). We found evidence of a high degree of heterogeneity between studies (Cochrane Q statistic: 382.84, p< 0.001; I2 proportion: 91.9%) and evidence of publication bias. However, the magnitude of our pooled odds ratio was consistent across a number of sensitivity analyses to account for heterogeneity and publication bias. In a secondary analysis with studies using viral non-suppression as their primary outcome, we also estimated a statistically significant pooled effect of alcohol use on viral non-suppression (pooled odds ratio: 2.47; 95% confidence interval: 1.58-3.87). Evidence suggests alcohol use is associated with ART non-adherence in Sub-Saharan Africa, potentially hindering achievement of the UNAIDS 90-90-90 HIV treatment targets.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/psicologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Infecções por HIV/virologia , Humanos , Adesão à Medicação/psicologia
19.
Neurobiol Dis ; 130: 104525, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31276792

RESUMO

Animal models that accurately recapitulate the accumulation of alpha-synuclein (α-syn) inclusions, progressive neurodegeneration of the nigrostriatal system and motor deficits can be useful tools for Parkinson's disease (PD) research. The preformed fibril (PFF) synucleinopathy model in rodents generally displays these PD-relevant features, however, the magnitude and predictability of these events is far from established. We therefore sought to optimize the magnitude of α-syn accumulation and nigrostriatal degeneration, and to understand the time course of both. Rats were injected unilaterally with different quantities of α-syn PFFs (8 or 16 µg of total protein) into striatal sites selected to concentrate α-syn inclusion formation in the substantia nigra pars compacta (SNpc). Rats displayed an α-syn PFF quantity-dependent increase in the magnitude of ipsilateral SNpc inclusion formation at 2 months and bilateral loss of nigral dopamine neurons at 6 months. Unilateral 16 µg PFF injection also resulted in modest sensorimotor deficits in forelimb adjusting steps associated with degeneration at 6 months. Bilateral injection of 16 µg α-syn PFFs resulted in symmetric bilateral degeneration equivalent to the ipsilateral nigral degeneration observed following unilateral 16 µg PFF injection (~50% loss). Bilateral PFF injections additionally resulted in alterations in several gait analysis parameters. These α-syn PFF parameters can be applied to generate a reproducible synucleinopathy model in rats with which to study pathogenic mechanisms and vet potential disease-modifying therapies.


Assuntos
Corpo Estriado/metabolismo , Substância Negra/metabolismo , Sinucleinopatias/metabolismo , alfa-Sinucleína/metabolismo , Animais , Corpo Estriado/patologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Ratos , Ratos Endogâmicos F344 , Substância Negra/patologia , Sinucleinopatias/patologia
20.
BMC Med ; 17(1): 6, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30764820

RESUMO

BACKGROUND: Interventions to alleviate stigma are demonstrating effectiveness across a range of conditions, though few move beyond the pilot phase, especially in low- and middle-income countries (LMICs). Implementation science offers tools to study complex interventions, understand barriers to implementation, and generate evidence of affordability, scalability, and sustainability. Such evidence could be used to convince policy-makers and donors to invest in implementation. However, the utility of implementation research depends on its rigor and replicability. Our objectives were to systematically review implementation studies of health-related stigma reduction interventions in LMICs and critically assess the reporting of implementation outcomes and intervention descriptions. METHODS: PubMed, CINAHL, PsycINFO, and EMBASE were searched for evaluations of stigma reduction interventions in LMICs reporting at least one implementation outcome. Study- and intervention-level characteristics were abstracted. The quality of reporting of implementation outcomes was assessed using a five-item rubric, and the comprehensiveness of intervention description and specification was assessed using the 12-item Template for Intervention Description and Replication (TIDieR). RESULTS: A total of 35 eligible studies published between 2003 and 2017 were identified; of these, 20 (57%) used qualitative methods, 32 (91%) were type 1 hybrid effectiveness-implementation studies, and 29 (83%) were evaluations of once-off or pilot implementations. No studies adopted a formal theoretical framework for implementation research. Acceptability (20, 57%) and feasibility (14, 40%) were the most frequently reported implementation outcomes. The quality of reporting of implementation outcomes was low. The 35 studies evaluated 29 different interventions, of which 18 (62%) were implemented across sub-Saharan Africa, 20 (69%) focused on stigma related to HIV/AIDS, and 28 (97%) used information or education to reduce stigma. Intervention specification and description was uneven. CONCLUSION: Implementation science could support the dissemination of stigma reduction interventions in LMICs, though usage to date has been limited. Theoretical frameworks and validated measures have not been used, key implementation outcomes like cost and sustainability have rarely been assessed, and intervention processes have not been presented in detail. Adapted frameworks, new measures, and increased LMIC-based implementation research capacity could promote the rigor of future stigma implementation research, helping the field deliver on the promise of stigma reduction interventions worldwide.


Assuntos
Ciência da Implementação , Estigma Social , África Subsaariana , Atenção à Saúde , Humanos , Pobreza
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