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1.
J Am Geriatr Soc ; 72(3): 903-915, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38147460

RESUMO

BACKGROUND: There is growing recognition of the importance of sex and gender differences within falls literature, but the characterization of such literature is uncertain. The aim of this scoping review was to (1) map the nature and extent of falls literature examining sex or gender differences among older adults, and (2) identify gaps and opportunities for further research and practice. METHODS: We used a scoping review methodology. Eligible studies included participants with a mean age of ≥ 60 years and study aims specifying falls and either sex or gender concepts. MEDLINE, Embase, CINAHL, Ageline, and Psychinfo databases were searched from inception to March 2, 2022. Records were screened and charted by six independent reviewers. Descriptive and narrative reports were generated. RESULTS: A total of 15,266 records were screened and 74 studies were included. Most studies reported on sex and gender differences in fall risk factors (n = 52, 70%), incidence/prevalence (n = 26, 35%), fall consequences (n = 22, 30%), and fall characteristics (n = 15, 20%). The majority of studies (n = 70, 95%) found significant sex or gender differences in relation to falls, with 39 (53%) identifying significant sex differences and 31 (42%) identifying significant gender differences. However, only three (4%) studies defined sex or gender concepts and only nine (12%) studies used sex or gender terms appropriately. Fifty-six (76%) studies had more female participants than males. Four (5%) were intervention studies. Studies did not report falls in line with guidelines nor use common fall definitions. CONCLUSION: Sex and gender differences are commonly reported in falls literature. It is critical for future research to use sex and gender terms appropriately and include similar sample sizes across all genders and sexes. In addition, there is a need to examine more gender-diverse populations and to develop interventions to prevent falls that address sex and gender differences among older adults.


Assuntos
Narração , Humanos , Masculino , Feminino , Idoso , Fatores Sexuais , Fatores de Risco , Estações do Ano
2.
Metabolites ; 13(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36984852

RESUMO

In the United States, besides the US territory Puerto Rico, Hawai'i is the only state that grows commercial coffee. In Hawai'i, coffee is the second most valuable agricultural commodity. Health benefits associated with moderate coffee consumption, including its antioxidant capacity, have been correlated to its bioactive components. Post-harvest techniques, coffee variety, degree of roasting, and brewing methods significantly impact the metabolites, lipids, minerals, and/or antioxidant capacity of brewed coffees. The goal of our study was to understand the impact of roasting and brewing methods on metabolites, lipids, biogenic amines, minerals, and antioxidant capacity of two Hawai'i-grown coffee (Coffea arabica) varieties, "Kona Typica" and "Yellow Catuai". Our results indicated that both roasting and coffee variety significantly modulated several metabolites, lipids, and biogenic amines of the coffee brews. Furthermore, regardless of coffee variety, the antioxidant capacity of roasted coffee brews was higher in cold brews. Similarly, total minerals were higher in "Kona Typica" cold brews followed by "Yellow Catuai" cold brews. Hawai'i-grown coffees are considered "specialty coffees" since they are grown in unique volcanic soils and tropical microclimates with unique flavors. Our studies indicate that both Hawai'i-grown coffees contain several health-promoting components. However, future studies are warranted to compare Hawai'i-grown coffees with other popular brand coffees and their health benefits in vivo.

3.
Brain ; 146(5): 1979-1992, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732292

RESUMO

Multiple sclerosis is clinically characterized by relapses and remissions (relapsing-remitting multiple sclerosis) that over time may evolve to a progressive course (secondary progressive multiple sclerosis) or as having a progressive course from disease onset (primary progressive multiple sclerosis). At present, it is not definitively known whether these clinical entities constitute a single pathological disease or whether these manifestations represent two distinct disease entities sharing inflammatory demyelination as a pathological feature. Here we show using a novel mouse model that CSF of primary progressive multiple sclerosis patients is unique in its capacity to induce motor disability and spinal cord pathology including demyelination, impaired remyelination, reactive astrogliosis and axonal damage. Notably, removal of immunoglobulin G from primary progressive multiple sclerosis CSF via filtration or immunodepletion attenuates its pathogenic capacity. Furthermore, injection of recombinant antibodies derived from primary progressive multiple sclerosis CSF recapitulates the pathology. Our findings suggest that the clinical and pathological features of primary progressive multiple sclerosis are antibody-mediated and pathogenically distinct from relapsing-remitting and secondary progressive multiple sclerosis. Our study has potentially important implications for the development of specific therapies for patients with primary progressive multiple sclerosis.


Assuntos
Pessoas com Deficiência , Transtornos Motores , Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Camundongos , Animais , Humanos , Esclerose Múltipla Crônica Progressiva/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Imunoglobulina G , Progressão da Doença , Líquido Cefalorraquidiano
4.
Brain Commun ; 4(4): fcac207, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36043141

RESUMO

Amyotrophic lateral sclerosis is a fatal neurodegenerative disease characterized by motor neuron degeneration. Approximately 90% of cases occur sporadically with no known cause while 10% are familial cases arising from known inherited genetic mutations. In vivo studies have predominantly utilized transgenic models harbouring amyotrophic lateral sclerosis-associated gene mutations, which have not hitherto elucidated mechanisms underlying motor neuron death or identified therapeutic targets specific to sporadic amyotrophic lateral sclerosis. Here we provide evidence demonstrating pathogenic differences in CSF from patients with sporadic amyotrophic lateral sclerosis and familial amyotrophic lateral sclerosis patients with mutations in SOD1, C9orf72 and TARDBP. Using a novel CSF-mediated animal model, we show that intrathecal delivery of sporadic amyotrophic lateral sclerosis patient-derived CSF into the cervical subarachnoid space in adult wild-type mice induces permanent motor disability which is associated with hallmark pathological features of amyotrophic lateral sclerosis including motor neuron loss, cytoplasmic TDP-43 translocation, reactive astrogliosis and microglial activation. Motor impairments are not induced by SOD1, C9orf72 or TARDBP CSF, although a moderate degree of histopathological change occurs in C9orf72 and TARDBP CSF-injected mice. By conducting a series of CSF filtration studies and global proteomic analysis of CSF, we identified apolipoprotein B-100 in sporadic amyotrophic lateral sclerosis CSF as the putative agent responsible for inducing motor disability, motor neuron degeneration and pathological translocation of TDP-43. Apolipoprotein B-100 alone is sufficient to recapitulate clinical and pathological outcomes in vivo and induce death of human induced pluripotent stem cell-derived motor neurons in vitro. Targeted removal of apolipoprotein B-100 from sporadic amyotrophic lateral sclerosis CSF via filtration or immunodepletion successfully attenuated the neurotoxic capacity of sporadic amyotrophic lateral sclerosis CSF to induce motor disability, motor neuron death, and TDP-43 translocation. This study presents apolipoprotein B-100 as a novel therapeutic target specific for the predominant sporadic form of amyotrophic lateral sclerosis and establishes proof-of-concept to support CSF pheresis as a therapeutic strategy for mitigating neurotoxicity in sporadic amyotrophic lateral sclerosis.

5.
Ophthalmic Plast Reconstr Surg ; 37(3S): S1-S5, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32932407

RESUMO

PURPOSE: Helicobacter pylori could theoretically induce ocular adnexal lymphoma (OAL) via 2 mechanisms: the first is that of infection within the ocular adnexa and the second is that of infection within the gastric mucosa, leading to the malignant transformation of lymphocytes that migrate to the ocular adnexa, forming a primary "ectopic" cancer. This study investigated if an association exists between gastric H. pylori or ocular adnexal H. pylori and OAL. METHODS: Prospective case-control study including cases with OAL and controls with nonlymphomatous pathologies. Gastric H. pylori infection was assessed via serologic antibody testing. Ocular adnexal infection was assessed via polymerase chain reaction testing for H. pylori and Chlamydia psittaci within ocular adnexal samples. RESULTS: Seventy-two patients were enrolled, of whom 18 had lymphoma and 54 nonlymphomatous pathologies. H. pylori antibodies were present in 5 cases (28%) and 18 controls (33%) (95% CI, 0.24%-2.50%, p = 0.78). All ocular adnexal specimens were negative for H. pylori and C. psittaci infection. The only relevant statistically significant difference between cases and controls was a history of gastric ulcer (95% CI, 1.23%-44.80%, p = 0.03). CONCLUSIONS: In the study's population, infection of gastric mucosa with H. pylori does not appear to influence the development of OAL. Also, H. pylori or C. psittaci infection within the ocular adnexa does not appear to influence the development of OAL. In the study's practice, authors do not recommend antibiotic administration or routine gastroscopy for patients with OAL. The authors do recommend referral of OAL patients with gastric symptoms to a gastroenterologist.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Linfoma de Zona Marginal Tipo Células B , Linfoma , Estudos de Casos e Controles , DNA Bacteriano , Mucosa Gástrica , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Humanos , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Estudos Prospectivos
6.
PLoS Genet ; 16(3): e1008604, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32130224

RESUMO

The influence of environmental insults on the onset and progression of mitochondrial diseases is unknown. To evaluate the effects of infection on mitochondrial disease we used a mouse model of Leigh Syndrome, where a missense mutation in the Taco1 gene results in the loss of the translation activator of cytochrome c oxidase subunit I (TACO1) protein. The mutation leads to an isolated complex IV deficiency that mimics the disease pathology observed in human patients with TACO1 mutations. We infected Taco1 mutant and wild-type mice with a murine cytomegalovirus and show that a common viral infection exacerbates the complex IV deficiency in a tissue-specific manner. We identified changes in neuromuscular morphology and tissue-specific regulation of the mammalian target of rapamycin pathway in response to viral infection. Taken together, we report for the first time that a common stress condition, such as viral infection, can exacerbate mitochondrial dysfunction in a genetic model of mitochondrial disease.


Assuntos
Deficiência de Citocromo-c Oxidase/genética , Infecções por Citomegalovirus/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Muromegalovirus/patogenicidade , Animais , Deficiência de Citocromo-c Oxidase/virologia , Infecções por Citomegalovirus/virologia , Modelos Animais de Doenças , Doença de Leigh/genética , Doença de Leigh/virologia , Camundongos , Camundongos Endogâmicos C57BL , Doenças Mitocondriais/virologia , Mutação/genética , Serina-Treonina Quinases TOR/genética
7.
Psychopharmacology (Berl) ; 236(12): 3385-3399, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31230145

RESUMO

RATIONALE: Schizophrenia and stimulant-induced psychosis (SIP) represent two different forms of psychotic disorder, with different etiologies. While many of the symptoms of psychosis are common to both disorders, there have been few direct comparisons between these conditions, especially when controlling for stimulant use in individuals with schizophrenia. OBJECTIVES: We directly compared both psychotic disorders with a comprehensive battery of clinical, neurocognitive and neuroanatomical measures. This included one group with SIP (and concurrent stimulant dependence) and two groups with schizophrenia (either with or without concurrent stimulant dependence). METHODS: Ninety-six participants were recruited from a marginalized urban population, which included 39 with SIP (and concurrent stimulant dependence), 18 with schizophrenia (without stimulant dependence), and 39 with schizophrenia (with concurrent stimulant dependence). All subjects had extensive clinical and neurocognitive evaluations, complemented with structural MRI including diffusion tensor imaging (DTI) sequences to determine regional brain volumes and white matter connectivity. RESULTS: Both positive and negative symptoms were greater in the SZ-dependent group than the other two. Neurocognitive function was broadly similar. The structural brain imaging revealed lateralized changes to the left parietal/temporal lobe, in which regional volumes were smaller in the SZ-dependent than the SZ-non-dependent group. DTI analysis indicated extensive decreases in fractional anisotropy, with parallel increases in radial diffusivity, in the SIP group compared to the SZ-dependent group. CONCLUSIONS: These findings reveal both similarities and differences between SIP and schizophrenia. Furthermore, schizophrenia with concurrent stimulant dependence may be associated with a different clinical and neuroanatomical profile as compared to schizophrenia alone.


Assuntos
Encéfalo/diagnóstico por imagem , Estimulantes do Sistema Nervoso Central/efeitos adversos , Imagem de Tensor de Difusão/métodos , Psicoses Induzidas por Substâncias/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Mapeamento Encefálico/métodos , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Psicoses Induzidas por Substâncias/psicologia , Psicologia do Esquizofrênico , Adulto Jovem
8.
Sci Rep ; 8(1): 6920, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-29703924

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

9.
Can J Ophthalmol ; 53(1): 29-33, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29426436

RESUMO

OBJECTIVE: To evaluate the effectiveness of a topical silicone gel on scars in patients who had undergone bilateral direct brow lift surgery. DESIGN: A randomized double-blind clinical trial with a placebo applied to one scar and topical silicone gel (Dermatix Ultra; Valeant Pharmaceuticals, Laval, Que.) used on the other scar for 2 months. PARTICIPANTS: Twelve patients (for a total of 24 surgical scars evaluated) were included in the study. METHODS: This study was performed in 2 academic hospitals of the University of Montreal in Montreal, Que. (Maisonneuve-Rosemont Hospital and Notre-Dame Hospital). Inclusion criteria were all bilateral direct brow lift surgeries performed in our hospitals. Exclusion criteria included revision surgery, silicone or latex allergy, and wound infection. Each patient received 2 tubes (1 with silicone gel and 1 with placebo) and applied 1 tube to their right brow scar and the other tube to their left brow scar, following the preassigned instructions. The patient and surgeon were blinded to the nature of the substance that was applied to each scar. At each visit, pictures of both scars were taken, and a questionnaire titled "The Patient and Observer Scar Assessment Scale" was filled out by the patient and the surgeon. A grade ranging from 0 to 10 was given on the multiple criteria in the questionnaire, and the sum of these grades was subsequently used for the data analysis. A lower sum was interpreted as improved scarring. At the end of the study, an independent evaluator graded both scars based on pictures. Follow-up visits were held on day 7, week 6, month 3, and month 6 after surgery. A comparison of the experimental and placebo group was performed with nonparametric tests of Wilcoxon signed rank. RESULTS: A total of 24 scars of 12 patients were analyzed (based on 4 follow-up visits). General improvement of scars was reported by the patient, the surgeon, and based on pictures. No statistically significant difference was found between the group treated with silicone gel and the group treated with placebo. All tests had a p value ≥0.08. CONCLUSIONS: We did not find a statistically significant difference between scars treated with silicone gel and scars treated with the placebo after direct brow lift surgery.


Assuntos
Cicatriz/terapia , Sobrancelhas/patologia , Ritidoplastia/métodos , Géis de Silicone/administração & dosagem , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
10.
Sci Rep ; 7(1): 8641, 2017 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-28819194

RESUMO

Following spinal cord injury (SCI), the innate immune response of microglia and infiltrating macrophages clears up cellular debris and promotes tissue repair, but it also inflicts secondary injury from inflammatory responses. Immunomodulation aimed at maximizing the beneficial effects while minimizing the detrimental roles of the innate immunity may aid functional recovery after SCI. However, intracellular drivers of global reprogramming of the inflammatory gene networks in the innate immune cells are poorly understood. Here we show that SCI resulted in an upregulation of histone deacetylase 3 (HDAC3) in the innate immune cells at the injury site. Remarkably, blocking HDAC3 with a selective small molecule inhibitor shifted microglia/macrophage responses towards inflammatory suppression, resulting in neuroprotective phenotypes and improved functional recovery in SCI model. Mechanistically, HDAC3 activity is largely responsible for histone deacetylation and inflammatory responses of primary microglia to classic inflammatory stimuli. Our results reveal a novel function of HDAC3 inhibitor in promoting functional recovery after SCI by dampening inflammatory cytokines, thus pointing towards a new direction of immunomodulation for SCI repair.

11.
PLoS One ; 10(8): e0136967, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26317208

RESUMO

Stroke results in brain tissue damage from ischemia and oxidative stress. Molecular regulators of the protective versus deleterious cellular responses after cerebral ischemia remain to be identified. Here, we show that deletion of Smad1, a conserved transcription factor that mediates canonical bone morphogenetic protein (BMP) signaling, results in neuroprotection in an ischemia-reperfusion (I/R) stroke model. Uninjured mice with conditional deletion of Smad1 in the CNS (Smad1 cKO) displayed upregulation of the reactive astrocyte marker GFAP and hypertrophic morphological changes in astrocytes compared to littermate controls. Additionally, cultured Smad1(-/-) astrocytes exhibited an enhanced antioxidant capacity. When subjected to I/R injury by transient middle cerebral artery occlusion (tMCAO), Smad1 cKO mice showed enhanced neuronal survival and improved neurological recovery at 7 days post-stroke. This neuroprotective phenotype is associated with attenuated reactive astrocytosis and neuroinflammation, along with reductions in oxidative stress, p53 induction, and apoptosis. Our data suggest that Smad1-mediated signaling pathway is involved in stroke pathophysiology and may present a new potential target for stroke therapy.


Assuntos
Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Proteína Smad1/deficiência , Animais , Astrócitos/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Camundongos , Estresse Oxidativo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
12.
PM R ; 7(8): 823-830, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25758531

RESUMO

OBJECTIVE: To investigate the prevalence and characteristics of recreational runners with medial and lateral heel whips. DESIGN: Observational cohort study. SETTING: Clinical research laboratory. PARTICIPANTS: A total of 256 recreationally active runners and joggers participated. MAIN OUTCOME MEASURES: High-definition video was acquired from a posterior view while runners ran at a self-selected pace on a treadmill. Heel whips, defined as the medial or lateral rotation of the foot in the transverse plane during initial swing, were measured with Dartfish software. Subjects were stratified by direction (medial and lateral) and severity (W_5-10 = 5-10 degrees; W_10+ = >10 degrees) of heel whip. Body mass index and gender comparisons, as well as measurement reliability, also were explored. RESULTS: Mean heel whip angle across runners was 0.4 degrees (medial) with a standard deviation of 9.2 degrees. Of the 512 feet analyzed, 274 (54%) demonstrated a 5 degree whip or greater. There was a similar number of medial and lateral heel whips observed (27% each). Female runners were twice as likely to demonstrate a lateral heel whip of greater than 8.9 degrees. Overweight runners had more medially directed whips when compared with normal and underweight runners. CONCLUSIONS: More than half of the recreational runners studied were observed to have a medial or lateral heel whip of greater than 5 degrees. These data reveal the age, body mass index, and gender distribution of recreational runners with and without heel whips.


Assuntos
Calcanhar/fisiologia , Recreação/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
14.
J Pharmacol Exp Ther ; 352(2): 327-37, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25502803

RESUMO

Phosphodiesterase 10A (PDE10A) inhibitors have therapeutic potential for the treatment of psychiatric and neurologic disorders, such as schizophrenia and Huntington's disease. One of the key requirements for successful central nervous system drug development is to demonstrate target coverage of therapeutic candidates in brain for lead optimization in the drug discovery phase and for assisting dose selection in clinical development. Therefore, we identified AMG 580 [1-(4-(3-(4-(1H-benzo[d]imidazole-2-carbonyl)phenoxy)pyrazin-2-yl)piperidin-1-yl)-2-fluoropropan-1-one], a novel, selective small-molecule antagonist with subnanomolar affinity for rat, primate, and human PDE10A. We showed that AMG 580 is suitable as a tracer for lead optimization to determine target coverage by novel PDE10A inhibitors using triple-stage quadrupole liquid chromatography-tandem mass spectrometry technology. [(3)H]AMG 580 bound with high affinity in a specific and saturable manner to both striatal homogenates and brain slices from rats, baboons, and human in vitro. Moreover, [(18)F]AMG 580 demonstrated prominent uptake by positron emission tomography in rats, suggesting that radiolabeled AMG 580 may be suitable for further development as a noninvasive radiotracer for target coverage measurements in clinical studies. These results indicate that AMG 580 is a potential imaging biomarker for mapping PDE10A distribution and ensuring target coverage by therapeutic PDE10A inhibitors in clinical studies.


Assuntos
Benzimidazóis/farmacologia , Encéfalo/enzimologia , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Pirazinas/farmacologia , Animais , Benzimidazóis/farmacocinética , Encéfalo/diagnóstico por imagem , Cromatografia Líquida , Feminino , Radioisótopos de Flúor , Humanos , Masculino , Espectrometria de Massas , Estrutura Molecular , Papio , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacocinética , Ligação Proteica , Pirazinas/farmacocinética , Ensaio Radioligante , Ratos Sprague-Dawley , Especificidade da Espécie , Estereoisomerismo , Ressonância de Plasmônio de Superfície , Distribuição Tecidual
15.
J Exp Med ; 211(5): 801-14, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24733831

RESUMO

Activation of intrinsic growth programs that promote developmental axon growth may also facilitate axon regeneration in injured adult neurons. Here, we demonstrate that conditional activation of B-RAF kinase alone in mouse embryonic neurons is sufficient to drive the growth of long-range peripheral sensory axon projections in vivo in the absence of upstream neurotrophin signaling. We further show that activated B-RAF signaling enables robust regenerative growth of sensory axons into the spinal cord after a dorsal root crush as well as substantial axon regrowth in the crush-lesioned optic nerve. Finally, the combination of B-RAF gain-of-function and PTEN loss-of-function promotes optic nerve axon extension beyond what would be predicted for a simple additive effect. We conclude that cell-intrinsic RAF signaling is a crucial pathway promoting developmental and regenerative axon growth in the peripheral and central nervous systems.


Assuntos
Axônios/fisiologia , Sistema Nervoso Central/embriologia , Sistema Nervoso Central/lesões , Regeneração Nervosa/fisiologia , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais/fisiologia , Animais , Axônios/enzimologia , Western Blotting , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , PTEN Fosfo-Hidrolase/metabolismo
16.
Front Biol (Beijing) ; 9(5): 356-366, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25554728

RESUMO

The pathophysiology underlying spinal cord injury is complex. Mechanistic understanding of the adaptive responses to injury is critical for targeted therapy aimed at reestablishing lost connections between proximal and distal neurons. After injury, cell-type specific gene transcription programs govern distinct cellular behaviors, and chromatin regulators play a central role in shaping the chromatin landscape to adjust transcriptional profiles in a context-dependent manner. In this review, we summarize recent progress on the pleiotropic roles of chromatin regulators in mediating the diverse adaptive behaviors of neurons and glial cells after spinal cord injury, and wherever possible, discuss the underlying mechanisms and genomic targets. We specifically draw attention to the perspective that takes into consideration the impact of epigenetic modulation on axon growth potential, together with its effect on wound-healing properties of glial cells. Epigenetic modulation of chromatin state represents an emerging therapeutic direction to promote neural repair and axon regeneration after spinal cord injury.

17.
J Neurosci ; 33(50): 19664-76, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24336730

RESUMO

Axon regeneration is hindered by a decline of intrinsic axon growth capability in mature neurons. Reversing this decline is associated with the induction of a large repertoire of regeneration-associated genes (RAGs), but the underlying regulatory mechanisms of the transcriptional changes are largely unknown. Here, we establish a correlation between diminished axon growth potential and histone 4 (H4) hypoacetylation. When neurons are triggered into a growth state, as in the conditioning lesion paradigm, H4 acetylation is restored, and RAG transcription is initiated. We have identified a set of target genes of Smad1, a proregenerative transcription factor, in conditioned DRG neurons. We also show that, during the epigenetic reprogramming process, histone-modifying enzymes work together with Smad1 to facilitate transcriptional regulation of RAGs. Importantly, targeted pharmacological modulation of the activity of histone-modifying enzymes, such as histone deacetylases, leads to induction of multiple RAGs and promotion of sensory axon regeneration in a mouse model of spinal cord injury. Our findings suggest epigenetic modulation as a potential therapeutic strategy to enhance axon regeneration.


Assuntos
Axônios/fisiologia , Epigênese Genética , Regeneração Nervosa/genética , Células Receptoras Sensoriais/fisiologia , Traumatismos da Medula Espinal/genética , Acetilação , Animais , Modelos Animais de Doenças , Gânglios Espinais/fisiologia , Histonas/genética , Camundongos , Regeneração Nervosa/fisiologia , Traumatismos da Medula Espinal/fisiopatologia
18.
Neurosci Lett ; 538: 32-7, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23353105

RESUMO

Ability to regenerate limbs and central nervous system (CNS) is unique to few vertebrates, most notably the axolotl (Ambystoma sp.). However, despite the fact the neurotransmitter receptors are involved in axonal regeneration, little is known regarding its expression profile. In this project, RT-PCR and qPCR were performed to gain insight into the neurotransmitter receptors present in Ambystoma. Its functional ability was studied by expressing axolotl receptors in Xenopus laevis oocytes by either injection of mRNA or by direct microtransplantation of brain membranes. Oocytes injected with axolotl mRNA expressed ionotropic receptors activated by GABA, aspartate+glycine and kainate, as well as metabotropic receptors activated by acetylcholine and glutamate. Interestingly, we did not see responses following the application of serotonin. Membranes from the axolotl brain were efficiently microtransplanted into Xenopus oocytes and two types of native GABA receptors that differed in the temporal course of their responses and affinities to GABA were observed. Results of this study are necessary for further characterization of axolotl neurotransmitter receptors and may be useful for guiding experiments aimed at understanding activity-dependant limb and CNS regeneration.


Assuntos
Ambystoma mexicanum/metabolismo , Encéfalo/metabolismo , Receptores de Neurotransmissores/metabolismo , Animais , Membrana Celular/metabolismo , Membrana Celular/transplante , Canais Iônicos/genética , Canais Iônicos/metabolismo , Oócitos/metabolismo , RNA/metabolismo , Ratos , Receptores de Neurotransmissores/genética , Transfecção , Xenopus laevis
19.
Cancer Immunol Immunother ; 62(2): 285-97, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22903385

RESUMO

Dendritic cell (DC)-based vaccination boosting antigen-specific immunity is being explored for the treatment of cancer and chronic viral infections. Although DC-based immunotherapy can induce immunological responses, its clinical benefit has been limited, indicating that further improvement of DC vaccine potency is essential. In this study, we explored the generation of a clinical-grade applicable DC vaccine with improved immunogenic potential by combining PD-1 ligand siRNA and target antigen mRNA delivery. We demonstrated that PD-L1 and PD-L2 siRNA delivery using DLin-KC2-DMA-containing lipid nanoparticles (LNP) mediated efficient and specific knockdown of PD-L expression on human monocyte-derived DC. The established siRNA-LNP transfection method did not affect DC phenotype or migratory capacity and resulted in acceptable DC viability. Furthermore, we showed that siRNA-LNP transfection can be successfully combined with both target antigen peptide loading and mRNA electroporation. Finally, we demonstrated that these PD-L-silenced DC loaded with antigen mRNA superiorly boost ex vivo antigen-specific CD8(+) T cell responses from transplanted cancer patients. Together, these findings indicate that our PD-L siRNA-LNP-modified DC are attractive cells for clinical-grade production and in vivo application to induce and boost immune responses not only in transplanted cancer patients, but likely also in other settings.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Inativação Gênica , Receptor de Morte Celular Programada 1/imunologia , Antígenos de Neoplasias/genética , Linfócitos T CD8-Positivos/imunologia , Eletroporação , Humanos , Imunoterapia , Leucócitos Mononucleares/imunologia , Lipídeos/imunologia , Ativação Linfocitária/imunologia , Nanopartículas , Proteína 2 Ligante de Morte Celular Programada 1/genética , Proteína 2 Ligante de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Transfecção
20.
Blood ; 120(9): 1916-22, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22611156

RESUMO

Anemia linked to a relative deficiency of renal erythropoietin production is a significant cause of morbidity and medical expenditures in the developed world. Recombinant erythropoietin is expensive and has been linked to excess cardiovascular events. Moreover, some patients become refractory to erythropoietin because of increased production of factors such as hepcidin. During fetal life, the liver, rather than the kidney, is the major source of erythropoietin. In the present study, we show that it is feasible to reactivate hepatic erythropoietin production and suppress hepcidin levels using systemically delivered siRNAs targeting the EglN prolyl hydroxylases specifically in the liver, leading to improved RBC production in models of anemia caused by either renal insufficiency or chronic inflammation with enhanced hepcidin production.


Assuntos
Eritropoetina/deficiência , Eritropoetina/genética , Pró-Colágeno-Prolina Dioxigenase/genética , RNA Interferente Pequeno/genética , Anemia/etiologia , Anemia/genética , Anemia/terapia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Sequência de Bases , Células Cultivadas , Eritropoese/genética , Eritropoetina/metabolismo , Estudos de Viabilidade , Feminino , Hepcidinas , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia , Inflamação/complicações , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Interferência de RNA , Insuficiência Renal/complicações
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