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1.
Bipolar Disord ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609342

RESUMO

INTRODUCTION: Cariprazine treats acute manic and depressive episodes in bipolar I disorder (BP-I), but its efficacy in preventing relapse of mood episode remains unknown. METHODS: In this phase 3b, double-blind, placebo-controlled study, patients with BP-I with acute manic or depressive episodes (each with/without mixed features), were treated with cariprazine 3.0 mg/day during a 16-week open-label treatment period; those who achieved stable remission within 8 weeks and remained stable for at least another 8 weeks were randomized to receive cariprazine 1.5 or 3.0 mg per day or placebo in the double-blind treatment period for up to 39 weeks. The primary efficacy endpoint was time to relapse of any mood episode. Adverse events (AEs) were assessed. RESULTS: Patients (440/896) enrolled in the open-label treatment period achieved stability criteria and were randomized to receive cariprazine 3.0 mg/day (n = 148), cariprazine 1.5 mg/day (n = 147), or placebo (n = 145) in the double-blind treatment period. Relapse rates were 17.9%, 16.8%, and 19.7% in the cariprazine 3.0 mg/day, cariprazine 1.5 mg/day, and placebo groups, respectively. Neither dose of cariprazine was more effective than placebo on the primary outcome (3.0 mg/day: HR = 0.89, [95% CI: 0.5, 1.5]; 1.5 mg/day: HR = 0.83, 95% CI [0.5, 1.4]). The most frequently reported AEs (≥5%) were akathisia, headache, insomnia, and nausea in the open-label treatment period and increased weight and insomnia in the double-blind treatment period. In the open-label and double-blind treatment periods, 7.5% and 1.6% of patients experienced an AE leading to discontinuation. CONCLUSION: Cariprazine was not superior to placebo in the prevention of relapses in this study. Relapse rates were unusually low in the placebo group. Cariprazine was well-tolerated.

2.
Proc Natl Acad Sci U S A ; 120(22): e2220159120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216542

RESUMO

Osteolectin is a recently identified osteogenic growth factor that binds to Integrin α11 (encoded by Itga11), promoting Wnt pathway activation and osteogenic differentiation by bone marrow stromal cells. While Osteolectin and Itga11 are not required for the formation of the skeleton during fetal development, they are required for the maintenance of adult bone mass. Genome-wide association studies in humans reported a single-nucleotide variant (rs182722517) 16 kb downstream of Osteolectin associated with reduced height and plasma Osteolectin levels. In this study, we tested whether Osteolectin promotes bone elongation and found that Osteolectin-deficient mice have shorter bones than those of sex-matched littermate controls. Integrin α11 deficiency in limb mesenchymal progenitors or chondrocytes reduced growth plate chondrocyte proliferation and bone elongation. Recombinant Osteolectin injections increased femur length in juvenile mice. Human bone marrow stromal cells edited to contain the rs182722517 variant produced less Osteolectin and underwent less osteogenic differentiation than that of control cells. These studies identify Osteolectin/Integrin α11 as a regulator of bone elongation and body length in mice and humans.


Assuntos
Condrócitos , Osteogênese , Adulto , Camundongos , Animais , Humanos , Condrócitos/metabolismo , Osteogênese/fisiologia , Lâmina de Crescimento , Estudo de Associação Genômica Ampla , Osso e Ossos , Diferenciação Celular , Integrinas/metabolismo , Proliferação de Células
3.
J Recept Signal Transduct Res ; 42(6): 580-587, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35984443

RESUMO

The mechanism underlying the antiepileptic actions of norepinephrine (NE) is unclear with conflicting results. Our objectives are to conclusively delineate the specific adrenergic receptor (AR) involved in attenuating hippocampal CA3 epileptiform activity and assess compounds for lead drug development. We utilized the picrotoxin model of seizure generation in rat brain slices using electrophysiological recordings. Epinephrine (EPI) reduced epileptiform burst frequency in a concentration-dependent manner. To identify the specific receptor involved in this response, the equilibrium dissociation constants were determined for a panel of ligands and compared with established binding values for α1, α2, and other receptor subtypes. Correlation and slope of unity were found for the α2A-AR, but not other receptors. Effects of different chemical classes of α-AR agonists at inhibiting epileptiform activity by potency (pEC50) and relative efficacy (RE) were determined. Compared with NE (pEC50, 6.20; RE, 100%), dexmedetomidine, an imidazoline (pEC50, 8.59; RE, 67.1%), and guanabenz, a guanidine (pEC50, 7.94; RE, 37.9%), exhibited the highest potency (pEC50). In contrast, the catecholamines, EPI (pEC50, 6.95; RE, 120%) and α-methyl-NE (pEC50, 6.38; RE, 116%) were the most efficacious. These findings confirm that CA3 epileptiform activity is mediated solely by α2A-ARs without activation of other receptor systems. These findings suggest a pharmacotherapeutic target for treating epilepsy and highlight the need for selective and efficacious α2A-AR agonists that can cross the blood-brain barrier.


Assuntos
Agonistas alfa-Adrenérgicos , Região CA3 Hipocampal , Norepinefrina , Convulsões , Animais , Ratos , Agonistas alfa-Adrenérgicos/farmacologia , Epinefrina/farmacologia , Ligantes , Norepinefrina/farmacologia , Receptores Adrenérgicos , Região CA3 Hipocampal/fisiopatologia , Convulsões/tratamento farmacológico , Técnicas In Vitro
4.
Front Synaptic Neurosci ; 13: 678575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220482

RESUMO

Auditory nerve fibers (ANFs) innervating the same inner hair cell (IHC) may have identical frequency tuning but different sound response properties. In cat and guinea pig, ANF response properties correlate with afferent synapse morphology and position on the IHC, suggesting a causal structure-function relationship. In mice, this relationship has not been fully characterized. Here we measured the emergence of synaptic morphological heterogeneities during maturation of the C57BL/6J mouse cochlea by comparing postnatal day 17 (p17, ∼3 days after hearing onset) with p34, when the mouse cochlea is mature. Using serial block face scanning electron microscopy and three-dimensional reconstruction we measured the size, shape, vesicle content, and position of 70 ribbon synapses from the mid-cochlea. Several features matured over late postnatal development. From p17 to p34, presynaptic densities (PDs) and post-synaptic densities (PSDs) became smaller on average (PDs: 0.75 to 0.33; PSDs: 0.58 to 0.31 µm2) and less round as their short axes shortened predominantly on the modiolar side, from 770 to 360 nm. Membrane-associated synaptic vesicles decreased in number from 53 to 30 per synapse from p17 to p34. Anatomical coupling, measured as PSD to ribbon distance, tightened predominantly on the pillar side. Ribbons became less spherical as long-axes lengthened only on the modiolar side of the IHC, from 372 to 541 nm. A decreasing gradient of synaptic ribbon size along the modiolar-pillar axis was detected only at p34 after aligning synapses of adjacent IHCs to a common reference frame (median volumes in nm3 × 106: modiolar 4.87; pillar 2.38). The number of ribbon-associated synaptic vesicles scaled with ribbon size (range 67 to 346 per synapse at p34), thus acquiring a modiolar-pillar gradient at p34, but overall medians were similar at p17 (120) and p34 (127), like ribbon surface area (0.36 vs. 0.34 µm2). PD and PSD morphologies were tightly correlated to each other at individual synapses, more so at p34 than p17, but not to ribbon morphology. These observations suggest that PDs and PSDs mature according to different cues than ribbons, and that ribbon size may be more influenced by cues from the IHC than the surrounding tissue.

5.
Mol Biol Cell ; 32(12): 1193-1201, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33852350

RESUMO

Centromeres are epigenetically defined by the centromere-specific histone H3 variant CENP-A. Specialized loading machinery, including the histone chaperone HJURP/Scm3, participates in CENP-A nucleosome assembly. However, Scm3/HJURP is missing from multiple lineages, including nematodes, with CENP-A-dependent centromeres. Here, we show that the extended N-terminal tail of Caenorhabditis elegans CENP-A contains a predicted structured region that is essential for centromeric chromatin assembly; removal of this region prevents CENP-A loading, resulting in failure of kinetochore assembly and defective chromosome condensation. By contrast, the N-tail mutant CENP-A localizes normally in the presence of endogenous CENP-A. The portion of the N-tail containing the predicted structured region binds to KNL-2, a conserved SANTA domain and Myb domain-containing protein (referred to as M18BP1 in vertebrates) specifically involved in CENP-A chromatin assembly. This direct interaction is conserved in the related nematode Caenorhabditis briggsae, despite divergence of the N-tail and KNL-2 primary sequences. Thus, the extended N-tail of CENP-A is essential for CENP-A chromatin assembly in C. elegans and partially substitutes for the function of Scm3/HJURP, in that it mediates a direct interaction between CENP-A and KNL-2. These results highlight an evolutionary variation on centromeric chromatin assembly in the absence of a dedicated CENP-A-specific chaperone/targeting factor of the Scm3/HJURP family.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteína Centromérica A/metabolismo , Centrômero/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Animais , Caenorhabditis elegans/genética , Proteína Centromérica A/genética , Ligação Proteica , Conformação Proteica , Domínios Proteicos
6.
PLoS One ; 16(3): e0248241, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33764985

RESUMO

Hyperglycemia is one of the major health concern in many parts of the world. One of the serious complications of high glucose levels is diabetic nephropathy. The preliminary microarray study performed on primary human renal tubular epithelial (hRTE) cells exposed to high glucose levels showed a significant downregulation of mTOR as well as its associated genes as well as lysosomal genes. Based on this preliminary data, the expression of various lysosomal genes as well as mTOR and its associated genes were analyzed in hRTE cells exposed to 5.5, 7.5, 11 and 16 mM glucose. The results validated the microarray analysis, which showed a significant decrease in the mRNA as well as protein expression of the selected genes as the concentration of glucose increased. Co-localization of lysosomal marker, LAMP1 with mTOR showed lower expression of mTOR as the glucose concentration increased, suggesting decrease in mTOR activity. Although the mechanism by which glucose affects the regulation of lysosomal genes is not well known, our results suggest that high levels of glucose may lead to decrease in mTOR expression causing the cells to enter an anabolic state with subsequent downregulation of lysosomal genes.


Assuntos
Antígeno AC133/análise , Hiperglicemia/genética , Túbulos Renais/metabolismo , Lisossomos/genética , Serina-Treonina Quinases TOR/genética , Antígeno AC133/genética , Células Cultivadas , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Glucose/metabolismo , Humanos , Hiperglicemia/metabolismo , Túbulos Renais/citologia , Lisossomos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Serina-Treonina Quinases TOR/metabolismo
7.
Biochem Biophys Rep ; 22: 100753, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32258441

RESUMO

We previously reported dysregulated expression of liver-derived messenger RNA (mRNA) and long noncoding RNA (lncRNA) in patients with advanced fibrosis resulting from nonalcoholic fatty liver disease (NAFLD). Here we sought to identify changes in mRNA and lncRNA levels associated with activation of hepatic stellate cells (HSCs), the predominant source of extracellular matrix production in the liver and key to NAFLD-related fibrogenesis. We performed expression profiling of mRNA and lncRNA from LX-2 cells, an immortalized human HSC cell line, treated to induce phenotypes resembling quiescent and myofibroblastic states. We identified 1964 mRNAs (1377 upregulated and 587 downregulated) and 1460 lncRNAs (665 upregulated and 795 downregulated) showing statistically significant evidence (FDR ≤0.05) for differential expression (fold change ≥|2|) between quiescent and activated states. Pathway analysis of differentially expressed genes showed enrichment for hepatic fibrosis (FDR = 1.35E-16), osteoarthritis (FDR = 1.47E-14), and axonal guidance signaling (FDR = 1.09E-09). We observed 127 lncRNAs/nearby mRNA pairs showing differential expression, the majority of which were dysregulated in the same direction. A comparison of differentially expressed transcripts in LX-2 cells with RNA-sequencing results from NAFLD patients with or without liver fibrosis revealed 1047 mRNAs and 91 lncRNAs shared between the two datasets, suggesting that some of the expression changes occurring during HSC activation can be observed in biopsied human tissue. These results identify lncRNA and mRNA expression patterns associated with activated human HSCs that appear to recapitulate human NAFLD fibrosis.

8.
Cancers (Basel) ; 11(4)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959792

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. Although diagnostic measures and surgical interventions have improved in recent years, the five-year survival rate for patients with advanced HCC remains bleak-a reality that is largely attributable to an absence of early stage symptoms, lack of adequate diagnostic and prognostic biomarkers, and the common occurrence of acquired resistance to chemotherapeutic agents during HCC treatment. A limited understanding of the molecular mechanisms underlying HCC pathogenesis also presents a challenge for the development of specific and efficacious pharmacological strategies to treat, halt, or prevent progression to advanced stages. Over the past decade, aldo-keto reductase family 1 member 10 (AKR1B10) has emerged as a potential biomarker for the diagnosis and prognosis of HCC, and experimental studies have demonstrated roles for this enzyme in biological pathways underlying the development and progression of HCC and acquired resistance to chemotherapeutic agents used in the treatment of HCC. Here we provide an overview of studies supporting the diagnostic and prognostic utility of AKR1B10, summarize the experimental evidence linking AKR1B10 with HCC and the induction of chemoresistance, and discuss the clinical value of AKR1B10 as a potential target for HCC-directed drug development. We conclude that AKR1B10-based therapies in the clinical management of specific HCC subtypes warrant further investigation.

9.
J Neurosci ; 39(23): 4434-4447, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30926748

RESUMO

Noise-induced excitotoxicity is thought to depend on glutamate. However, the excitotoxic mechanisms are unknown, and the necessity of glutamate for synapse loss or regeneration is unclear. Despite absence of glutamatergic transmission from cochlear inner hair cells in mice lacking the vesicular glutamate transporter-3 (Vglut3KO ), at 9-11 weeks, approximately half the number of synapses found in Vglut3WT were maintained as postsynaptic AMPA receptors juxtaposed with presynaptic ribbons and voltage-gated calcium channels (CaV1.3). Synapses were larger in Vglut3KO than Vglut3WT In Vglut3WT and Vglut3+/- mice, 8-16 kHz octave-band noise exposure at 100 dB sound pressure level caused a threshold shift (∼40 dB) and a loss of synapses (>50%) at 24 h after exposure. Hearing threshold and synapse number partially recovered by 2 weeks after exposure as ribbons became larger, whereas recovery was significantly better in Vglut3WT Noise exposure at 94 dB sound pressure level caused auditory threshold shifts that fully recovered in 2 weeks, whereas suprathreshold hearing recovered faster in Vglut3WT than Vglut3+/- These results, from mice of both sexes, suggest that spontaneous repair of synapses after noise depends on the level of Vglut3 protein or the level of glutamate release during the recovery period. Noise-induced loss of presynaptic ribbons or postsynaptic AMPA receptors was not observed in Vglut3KO , demonstrating its dependence on vesicular glutamate release. In Vglut3WT and Vglut3+/-, noise exposure caused unpairing of presynaptic ribbons and presynaptic CaV1.3, but not in Vglut3KO where CaV1.3 remained clustered with ribbons at presynaptic active zones. These results suggest that, without glutamate release, noise-induced presynaptic Ca2+ influx was insufficient to disassemble the active zone. However, synapse volume increased by 2 weeks after exposure in Vglut3KO , suggesting glutamate-independent mechanisms.SIGNIFICANCE STATEMENT Hearing depends on glutamatergic transmission mediated by Vglut3, but the role of glutamate in synapse loss and repair is unclear. Here, using mice of both sexes, we show that one copy of the Vglut3 gene is sufficient for noise-induced threshold shift and loss of ribbon synapses, but both copies are required for normal recovery of hearing function and ribbon synapse number. Impairment of the recovery process in mice having only one functional copy suggests that glutamate release may promote synapse regeneration. At least one copy of the Vglut3 gene is necessary for noise-induced synapse loss. Although the excitotoxic mechanism remains unknown, these findings are consistent with the presumption that glutamate is the key mediator of noise-induced synaptopathy.


Assuntos
Sistemas de Transporte de Aminoácidos Acídicos/fisiologia , Ácido Glutâmico/fisiologia , Células Ciliadas Auditivas Internas/fisiologia , Perda Auditiva Provocada por Ruído/fisiopatologia , Sinapses/fisiologia , Envelhecimento/fisiologia , Sistemas de Transporte de Aminoácidos Acídicos/deficiência , Sistemas de Transporte de Aminoácidos Acídicos/genética , Animais , Limiar Auditivo/fisiologia , Cálcio/metabolismo , Potenciais Evocados Auditivos , Exocitose , Feminino , Dosagem de Genes , Genes Reporter , Células Ciliadas Auditivas Externas/fisiologia , Transporte de Íons , Masculino , Camundongos , Camundongos Knockout , Receptores de AMPA/fisiologia , Recuperação de Função Fisiológica , Gânglio Espiral da Cóclea/citologia , Sinapses/ultraestrutura
10.
Am Fam Physician ; 98(8): 508-515, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30277728

RESUMO

Depression affects an estimated 8% of persons in the United States and accounts for more than $210 billion in health care costs annually. The U.S. Preventive Services Task Force (USPSTF) and American Academy of Family Physicians recommend screening for depression in the general adult population. Additionally, the USPSTF recommends screening children and adolescents 12 to 18 years of age for major depressive disorder. All screening should be implemented with adequate systems in place to ensure accurate diagnosis, effective treatment, and appropriate follow-up. The two-item and nine-item Patient Health Questionnaires (PHQs) are commonly used validated screening tools. The PHQ-2 has sensitivity comparable with the PHQ-9 in most populations; however, the specificity of the PHQ-9 ranges from 91% to 94%, compared with 78% to 92% for the PHQ-2. If the PHQ-2 is positive for depression, the PHQ-9 or a clinical interview should be administered. Screening all postpartum women for depression is recommended by the USPSTF, American Academy of Family Physicians, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists. Women should be screened for depression at least once during the perinatal period using the PHQ-2, PHQ-9, or Edinburgh Postnatal Depression Scale. In older adults, the Geriatric Depression Scale is also an appropriate screening tool for depression. If screening is positive for possible depression, the diagnosis should be confirmed using Diagnostic and Statistical Manual of Mental Disorders, 5th ed., criteria.


Assuntos
Depressão Pós-Parto/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Programas de Rastreamento/normas , Escalas de Graduação Psiquiátrica/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Currículo , Transtorno Depressivo Maior/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Educação Médica Continuada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Sensibilidade e Especificidade , Inquéritos e Questionários , Estados Unidos/epidemiologia
11.
Mol Pharmacol ; 80(4): 747-58, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21791575

RESUMO

The role of α(1)-adrenergic receptors (α(1)ARs) in cognition and mood is controversial, probably as a result of past use of nonselective agents. α(1A)AR activation was recently shown to increase neurogenesis, which is linked to cognition and mood. We studied the effects of long-term α(1A)AR stimulation using transgenic mice engineered to express a constitutively active mutant (CAM) form of the α(1A)AR. CAM-α(1A)AR mice showed enhancements in several behavioral models of learning and memory. In contrast, mice that have the α(1A)AR gene knocked out displayed poor cognitive function. Hippocampal brain slices from CAM-α(1A)AR mice demonstrated increased basal synaptic transmission, paired-pulse facilitation, and long-term potentiation compared with wild-type (WT) mice. WT mice treated with the α(1A)AR-selective agonist cirazoline also showed enhanced cognitive functions. In addition, CAM-α(1A)AR mice exhibited antidepressant and less anxious phenotypes in several behavioral tests compared with WT mice. Furthermore, the lifespan of CAM-α(1A)AR mice was 10% longer than that of WT mice. Our results suggest that long-term α(1A)AR stimulation improves synaptic plasticity, cognitive function, mood, and longevity. This may afford a potential therapeutic target for counteracting the decline in cognitive function and mood associated with aging and neurological disorders.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 1/farmacologia , Afeto/fisiologia , Cognição/fisiologia , Longevidade/fisiologia , Plasticidade Neuronal/fisiologia , Receptores Adrenérgicos alfa 1/metabolismo , Afeto/efeitos dos fármacos , Animais , Cognição/efeitos dos fármacos , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Longevidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Knockout , Camundongos Transgênicos , Plasticidade Neuronal/efeitos dos fármacos , Técnicas de Cultura de Órgãos , Receptores Adrenérgicos alfa 1/fisiologia , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
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