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1.
Theranostics ; 14(1): 56-74, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164158

RESUMO

Rationale: Promotion of mitophagy is considered a promising strategy for the treatment of neurodegenerative diseases including Alzheimer's disease (AD). The development of mitophagy-specific inducers with low toxicity and defined molecular mechanisms is essential for the clinical application of mitophagy-based therapy. The aim of this study was to investigate the potential of a novel small-molecule mitophagy inducer, ALT001, as a treatment for AD. Methods: ALT001 was developed through chemical optimization of an isoquinolium scaffold, which was identified from a chemical library screening using a mitophagy reporter system. In vitro and in vivo experiments were conducted to evaluate the potential of ALT001 as a mitophagy-targeting therapeutic agent and to investigate the molecular mechanisms underlying ALT001-induced mitophagy. The therapeutic effect of ALT001 was assessed in SH-SY5Y cells expressing mutant APP and mouse models of AD (5×FAD and PS2APP) by analyzing mitochondrial dysfunction and cognitive defects. Results: ALT001 specifically induces mitophagy both in vitro and in vivo but is nontoxic to mitochondria. Interestingly, we found that ALT001 induces mitophagy through the ULK1-Rab9-dependent alternative mitophagy pathway independent of canonical mitophagy pathway regulators such as ATG7 and PINK1. Importantly, ALT001 reverses mitochondrial dysfunction in SH-SY5Y cells expressing mutant APP in a mitophagy-dependent manner. ALT001 induces alternative mitophagy in mice and restores the decreased mitophagy level in a 5×FAD AD model mouse. In addition, ALT001 reverses mitochondrial dysfunction and cognitive defects in the PS2APP and 5×FAD AD mouse models. AAV-mediated silencing of Rab9 in the hippocampus further confirmed that ALT001 exerts its therapeutic effect through alternative mitophagy. Conclusion: Our results highlight the therapeutic potential of ALT001 for AD via alleviation of mitochondrial dysfunction and indicate the usefulness of the ULK1-Rab9 alternative mitophagy pathway as a therapeutic target.


Assuntos
Doença de Alzheimer , Doenças Mitocondriais , Neuroblastoma , Humanos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Mitofagia , Modelos Animais de Doenças , Isoquinolinas/farmacologia , Cognição
2.
Curr Biol ; 34(4): 740-754.e4, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38262417

RESUMO

Brown algae are the only group of heterokont protists exhibiting complex multicellularity. Since their origin, brown algae have adapted to various marine habitats, evolving diverse thallus morphologies and gamete types. However, the evolutionary processes behind these transitions remain unclear due to a lack of a robust phylogenetic framework and problems with time estimation. To address these issues, we employed plastid genome data from 138 species, including heterokont algae, red algae, and other red-derived algae. Based on a robust phylogeny and new interpretations of algal fossils, we estimated the geological times for brown algal origin and diversification. The results reveal that brown algae first evolved true multicellularity, with plasmodesmata and reproductive cell differentiation, during the late Ordovician Period (ca. 450 Ma), coinciding with a major diversification of marine fauna (the Great Ordovician Biodiversification Event) and a proliferation of multicellular green algae. Despite its early Paleozoic origin, the diversification of major orders within this brown algal clade accelerated only during the Mesozoic Era, coincident with both Pangea rifting and the diversification of other heterokont algae (e.g., diatoms), coccolithophores, and dinoflagellates, with their red algal-derived plastids. The transition from ancestral isogamy to oogamy was followed by three simultaneous reappearances of isogamy during the Cretaceous Period. These are concordant with a positive character correlation between parthenogenesis and isogamy. Our new brown algal timeline, combined with a knowledge of past environmental conditions, shed new light on brown algal diversification and the intertwined evolution of multicellularity and sexual reproduction.


Assuntos
Phaeophyceae , Rodófitas , Filogenia , Eucariotos/genética , Plantas , Rodófitas/genética , Plastídeos/genética , Phaeophyceae/genética , Evolução Molecular
3.
Food Funct ; 14(21): 9650-9670, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37843873

RESUMO

Alzheimer's disease (AD) is a common neurodegenerative disease worldwide and is accompanied by memory deficits, personality changes, anxiety, depression, and social difficulties. For treatment of AD, many researchers have attempted to find medicinal resources with high effectiveness and without side effects. Oligonol is a low molecular weight polypeptide derived from lychee fruit extract. We investigated the effects of oligonol in 5 × FAD transgenic AD mice, which developed severe amyloid pathology, through behavioral tests (Barnes maze, marble burying, and nestle shredding) and molecular experiments. Oligonol treatment attenuated blood glucose levels and increased the antioxidant response in the livers of 5 × FAD mice. Moreover, the behavioral score data showed improvements in anxiety, depressive behavior, and cognitive impairment following a 2-month course of orally administered oligonol. Oligonol treatment not only altered the circulating levels of cytokines and adipokines in 5 × FAD mice, but also significantly enhanced the mRNA and protein levels of antioxidant enzymes and synaptic plasticity in the brain cortex and hippocampus. Therefore, we highlight the therapeutic potential of oligonol to attenuate neuropsychiatric problems and improve memory deficits in the early stage of AD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Animais , Antioxidantes/farmacologia , Doença de Alzheimer/patologia , Encéfalo , Fígado , Camundongos Transgênicos , Transtornos da Memória/tratamento farmacológico
4.
Bioconjug Chem ; 34(1): 238-247, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36516871

RESUMO

As a counterpart to antibody-drug conjugates (ADCs), aptamer-drug conjugates (ApDCs) have been considered a promising strategy for targeted therapy due to the various benefits of aptamers. However, an aptamer merely serves as a targeting ligand in ApDCs, whereas the antibody enables the unexpected therapeutic efficacy of ADCs through antibody-dependent cellular cytotoxicity (ADCC). In this study, we developed a tumor-specific aptamer with an effector function and used it to confirm the feasibility of more potent ApDCs. First, we designed a nucleolin (NCL)-binding G-quadruplex (GQ) library based on the ability of NCL to bind to telomeric sequences. We then identified a bifunctional GQ aptamer (BGA) inhibiting the catalytic activity of topoisomerase 1 (TOP1) by forming an irreversible cleavage complex. Our BGA specifically targeted NCL-positive MCF-7 cells, exhibiting antiproliferative activity, and this suggested that tumor-specific therapeutic aptamers can be developed by using a biased library to screen aptamer candidates for functional targets. Finally, we utilized DM1, which has a synergistic interaction with TOP1 inhibitors, as a conjugated drug. BGA-DM1 exerted an anticancer effect 20-fold stronger than free DM1 and even 10-fold stronger than AS1411 (NCL aptamer)-DM1, highlighting our approach to develop synergistic ApDCs. Therefore, we anticipate that our library might be utilized for the identification of aptamers with effector functions. Furthermore, by employing such aptamers and appropriate drugs, synergistic ApDCs can be developed for targeted cancer therapy in a manner distinct from how ADCs exhibit additional therapeutic efficacy.


Assuntos
Aptâmeros de Nucleotídeos , DNA Topoisomerases Tipo I , Proteínas de Ligação a RNA , Humanos , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/metabolismo , Células MCF-7 , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/efeitos dos fármacos , Proteínas de Ligação a RNA/metabolismo , DNA Topoisomerases Tipo I/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , Sinergismo Farmacológico , Nucleolina
5.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35027452

RESUMO

Alzheimer's disease (AD) is characterized by complex, multifactorial neuropathology, suggesting that small molecules targeting multiple neuropathological factors are likely required to successfully impact clinical progression. Acid sphingomyelinase (ASM) activation has been recognized as an important contributor to these neuropathological features in AD, leading to the concept of using ASM inhibitors for the treatment of this disorder. Here we report the identification of KARI 201, a direct ASM inhibitor evaluated for AD treatment. KARI 201 exhibits highly selective inhibition effects on ASM, with excellent pharmacokinetic properties, especially with regard to brain distribution. Unexpectedly, we found another role of KARI 201 as a ghrelin receptor agonist, which also has therapeutic potential for AD treatment. This dual role of KARI 201 in neurons efficiently rescued neuropathological features in AD mice, including amyloid beta deposition, autophagy dysfunction, neuroinflammation, synaptic loss, and decreased hippocampal neurogenesis and synaptic plasticity, leading to an improvement in memory function. Our data highlight the possibility of potential clinical application of KARI 201 as an innovative and multifaceted drug for AD treatment.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Neuropatologia/métodos , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Memória , Camundongos , Plasticidade Neuronal , Neurônios/metabolismo , Receptores de Grelina/metabolismo , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo
6.
Molecules ; 26(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34684684

RESUMO

Memory deterioration in Alzheimer's disease (AD) is thought to be underpinned by aberrant amyloid ß (Aß) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3ß (p-GSK3ß-S9) and cleaved caspase 3, which are involved in Aß-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Avena/química , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal , Extratos Vegetais/farmacologia
7.
Sci Rep ; 11(1): 8326, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859286

RESUMO

Metabolic syndrome, which increases the risk of obesity and type 2 diabetes has emerged as a significant issue worldwide. Recent studies have highlighted the relationship between metabolic imbalance and neurological pathologies such as memory loss. Glucagon-like peptide 1 (GLP-1) secreted from gut L-cells and specific brain nuclei plays multiple roles including regulation of insulin sensitivity, inflammation and synaptic plasticity. Although GLP-1 and GLP-1 receptor agonists appear to have neuroprotective function, the specific mechanism of their action in brain remains unclear. We investigated whether exendin-4, as a GLP-1RA, improves cognitive function and brain insulin resistance in metabolic-imbalanced mice fed a high-fat diet. Considering the result of electrophysiological experiments, exendin-4 inhibits the reduction of long term potentiation (LTP) in high fat diet mouse brain. Further, we identified the neuroprotective effect of exendin-4 in primary cultured hippocampal and cortical neurons in in vitro metabolic imbalanced condition. Our results showed the improvement of IRS-1 phosphorylation, neuronal complexity, and the mature of dendritic spine shape by exendin-4 treatment in metabolic imbalanced in vitro condition. Here, we provides significant evidences on the effect of exendin-4 on synaptic plasticity, long-term potentiation, and neural structure. We suggest that GLP-1 is important to treat neuropathology caused by metabolic syndrome.


Assuntos
Dendritos/patologia , Exenatida/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Potenciação de Longa Duração/efeitos dos fármacos , Neurônios/citologia , Obesidade/patologia , Obesidade/fisiopatologia , Animais , Células Cultivadas , Córtex Cerebral/citologia , Cognição/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Receptor do Peptídeo Semelhante ao Glucagon 1/fisiologia , Hipocampo/citologia , Resistência à Insulina , Camundongos , Plasticidade Neuronal/efeitos dos fármacos , Obesidade/etiologia , Obesidade/psicologia
8.
Mitochondrial DNA B Resour ; 6(1): 10-12, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33490586

RESUMO

We de novo assembled the complete mitochondrial genome of the green peach aphid, Myzus persicae, using its genomic DNA isolated from the bell pepper in Korea. The circular mitogenome of M. persicae is 16,936 bp long and contains the standard 37 genes: 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, as well as a single control region of 798 bp. Given the high AT ratio (84.1%) of the M. persicae mitogenome, we found, through the comparison of the Chinese M. persicae mitogenomes, that approximately 1.6% of the mitogenome is polymorphic, including 30 single nucleotide polymorphisms (SNPs), 12 insertions and deletions (INDELs), and large sequence variations in the control region. To resolve the phylogenetic position of M. persicae, we analyzed all mitochondrial protein-coding genes from 38 species within the Aphidoidea superfamily, with Adelges laricis as an outgroup. Our M. persicae sample was significantly grouped with three existing M. persicae samples, and the species belonging to the family Aphididae formed a monophyletic clade.

9.
Saf Health Work ; 11(4): 500-508, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33329917

RESUMO

BACKGROUND: Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective. METHODS: Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined. RESULTS: On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16-56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials. CONCLUSION: We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.

10.
Brain Sci ; 10(8)2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32806774

RESUMO

Anodal transcranial direct current stimulation (tDCS) is a painless noninvasive method that reportedly improves cognitive function in Alzheimer's disease (AD) by stimulating the brain. However, its underlying mechanism remains unclear. Thus, the present study investigates the cognitive effects in a 5xFAD AD mouse model using electrophysiological and pathological methods. We used male 5xFAD C57BL/6J and male C57BL/6J wild-type mice; the dementia model was confirmed through DNA sequencing. The verified AD and wild-type mice were randomly assigned into four groups of five mice each: an induced AD group receiving tDCS treatment (Stim-AD), an induced AD group not receiving tDCS (noStim-AD), a non-induction group receiving tDCS (Stim-WT), and a non-induction group not receiving tDCS (noStim-WT). In the Stim group, mice received tDCS in the frontal bregma areas at an intensity of 200 µA for 20 min. After 2 weeks of treatment, we decapitated the mice, removed the hippocampus from the brain, confirmed its neuronal activation through excitatory postsynaptic potential (EPSP) recording, and performed molecular experiments on the remaining tissue using western blots. EPSP significantly increased in the Stim-AD group compared to that in the noStim-AD, which was comparable to that in the non-induced groups, Stim-WT and noStim-WT. There were no significant differences in cyclic amp-response element binding protein (CREB), phosphorylated CREB (pCREB), and Brain-derived neurotrophic factor (BDNF) levels in the Stim-AD group compared to those in the noStim-AD group. This study demonstrated that a tDCS in both frontal lobes of a transgenic 5xFAD mouse model affects long-term potentiation, indicating possible enhancement of cognitive function.

11.
Neuropharmacology ; 176: 108196, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32598912

RESUMO

Oleuropein (OLE), a major phenolic compound in olive oil, has been demonstrated to possess several pharmacological properties, including neuroprotection. However, the cognitive effects of OLE and its action mechanism have remained unclear. Here, we examined the effect of OLE on long-term potentiation (LTP) using field excitatory postsynaptic potential recorded in the CA1 region of both wild-type and 5XFAD mouse hippocampal slice preparations. In initial experiments with wild-type mice, 100 µM/1 h of OLE produced significant enhancements in the LTPs of Schaffer collateral synapses in the CA1 regions of treated mice, as compared to the vehicle-treated controls. As assessed by surface biotinylation and Western blot analysis, OLE caused a significant increase in protein kinase A (PKA)-mediated phosphorylation and the surface expression of GluA1 containing calcium permeable- amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (CP-AMPARs) in the hippocampus. Furthermore, we found that OLE enhanced LTP induction, while GluA1 phosphorylation occurred in an N-methyl-d-aspartate receptors (NMDARs)-independent manner. The OLE-induced CP-AMPAR trafficking resulted from elevated intracellular Ca2+ levels via regulation of phospholipase C (PLC). Consistently, we also found involvement of NMDAR-independent LTP and GluA1 phosphorylation in 5XFAD transgenic mice hippocampal slices treated with OLE. Together, our findings indicate that OLE may regulate beneficial effects on memory through the facilitation of CP-AMPAR trafficking and synaptic transmission.


Assuntos
Cálcio/metabolismo , Hipocampo/metabolismo , Líquido Intracelular/metabolismo , Glucosídeos Iridoides/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Receptores de AMPA/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Hipocampo/efeitos dos fármacos , Líquido Intracelular/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Técnicas de Cultura de Órgãos , Permeabilidade/efeitos dos fármacos , Vasodilatadores/metabolismo , Vasodilatadores/farmacologia
12.
J Microbiol ; 58(3): 176-192, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32108314

RESUMO

Microbial communities present in diverse environments from deep seas to human body niches play significant roles in the complex ecosystem and human health. Characterizing their structural and functional diversities is indispensable, and many approaches, such as microscopic observation, DNA fingerprinting, and PCR-based marker gene analysis, have been successfully applied to identify microorganisms. Since the revolutionary improvement of DNA sequencing technologies, direct and high-throughput analysis of genomic DNA from a whole environmental community without prior cultivation has become the mainstream approach, overcoming the constraints of the classical approaches. Here, we first briefly review the history of environmental DNA analysis applications with a focus on profiling the taxonomic composition and functional potentials of microbial communities. To this end, we aim to introduce the shotgun metagenomic sequencing (SMS) approach, which is used for the untargeted ("shotgun") sequencing of all ("meta") microbial genomes ("genomic") present in a sample. SMS data analyses are performed in silico using various software programs; however, in silico analysis is typically regarded as a burden on wet-lab experimental microbiologists. Therefore, in this review, we present microbiologists who are unfamiliar with in silico analyses with a basic and practical SMS data analysis protocol. This protocol covers all the bioinformatics processes of the SMS analysis in terms of data preprocessing, taxonomic profiling, functional annotation, and visualization.


Assuntos
Bactérias , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenoma/genética , Metagenômica/métodos , Microbiota/genética , Análise de Sequência de DNA/métodos , Software , Animais , Bactérias/classificação , Bactérias/genética , Biologia Computacional/métodos , Conjuntos de Dados como Assunto , Instruções Programadas como Assunto , Água do Mar/microbiologia , Microbiologia do Solo , Stichopus/microbiologia
13.
Mol Neurobiol ; 57(1): 315-330, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31332763

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline and dementia with no effective treatment. Here, we investigated a novel compound from oats named avenanthramide-C (Avn-C), on AD-related memory impairment and behavioral deficits in transgenic mouse models. Acute hippocampal slices of wild-type or AD transgenic mice were treated with Avn-C in the presence or absence of oligomeric Aß42. LTP analyses and immunoblotting were performed to assess the effect of Avn-C on Aß-induced memory impairment. To further investigate the effect of Avn-C on impaired memory and Aß pathology, two different AD transgenic mice (Tg2576 and 5XFAD) models were orally treated with either Avn-C or vehicle for 2 weeks. They were then assessed for the effect of the treatment on neuropathologies and behavioral impairments. Avn-C reversed impaired LTP in both ex vivo- and in vivo-treated AD mice hippocampus. Oral administration (6 mg/kg per day) for 2 weeks in AD mice leads to improved recognition and spatial memory, reduced caspase-3 cleavage, reversed neuroinflammation, and to accelerated glycogen synthase kinase-3ß (pS9GSK-3ß) and interleukin (IL-10) levels. Avn-C exerts its beneficial effects by binding to α1A adrenergic receptors to stimulate adenosine monophosphate-activated kinase (AMPK). All of the beneficial effects of Avn-C on LTP retrieval could be blocked by prazosin hydrochloride, a specific inhibitor of α1A adrenergic receptors. Our findings provide evidence, for the first time, that oats' Avn-C reverses the AD-related memory and behavioral impairments, and establish it as a potential candidate for Alzheimer's disease drug development.


Assuntos
Doença de Alzheimer/fisiopatologia , Cognição/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Adenilato Quinase/metabolismo , Administração Oral , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Inflamação/patologia , Potenciação de Longa Duração/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Receptores Adrenérgicos alfa 1/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Memória Espacial , ortoaminobenzoatos/administração & dosagem
14.
Toxicol Ind Health ; 35(8): 507-519, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31462197

RESUMO

In commercial products such as household deodorants or biocides, didecyldimethylammonium chloride (DDAC) often serves as an antimicrobial agent, citral serves as a fragrance agent, and the excipient ethylene glycol (EG) is used to dissolve the active ingredients. The skin sensitization (SS) potentials of each of these substances are still being debated. Moreover, mixtures of DDAC or citral with EG have not been evaluated for SS potency. The in vitro alternative assay called human Cell Line Activation Test (h-CLAT) and Direct Peptide Reactivity Assay (DPRA) served to address these issues. On three independent runs of h-CLAT, DDAC and citral were predicted to be sensitizers while EG was predicted to be a non-sensitizer and also by the DPRA. Mixtures of DDAC or citral with EG at ratios of 7:3 and 1:4 w/v were all positive by the h-CLAT in terms of SS potential but SS potency was mitigated as the proportion of EG increased. Citral and its EG mixtures were all positive but DDAC and its EG mixtures were all negative by the DPRA, indicating that the DPRA method is not suitable for chemicals with pro-hapten characteristics. Since humans can be occupationally or environmentally exposed to mixtures of excipients with active ingredients, the present study may give insights into further investigations of the SS potentials of various chemical mixtures.


Assuntos
Monoterpenos Acíclicos/efeitos adversos , Etilenoglicol/efeitos adversos , Excipientes/efeitos adversos , Compostos de Amônio Quaternário/efeitos adversos , Testes de Irritação da Pele/métodos , Pele/efeitos dos fármacos , Monoterpenos Acíclicos/administração & dosagem , Alternativas aos Testes com Animais/métodos , Antígeno B7-2/metabolismo , Bioensaio/métodos , Linhagem Celular , Etilenoglicol/administração & dosagem , Excipientes/administração & dosagem , Humanos , Molécula 1 de Adesão Intercelular/metabolismo
15.
Sci Rep ; 9(1): 10955, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358853

RESUMO

Acute stress facilitates long-term potentiation (LTP) in the mouse hippocampus by modulating glucocorticoid receptors and ion channels. Here, we analysed whether this occurs in mouse models of Alzheimer's disease (AD) with impaired LTP induction. We found that a brief 30 min restraint stress protocol reversed the impaired LTP assessed with field excitatory postsynaptic potential recordings at cornu ammonis 3-1 (CA3-CA1) synapses in both Tg2576 and 5XFAD mice. This effect was accompanied by increased phosphorylation and surface expression of glutamate A1 (GluA1) -containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). Moreover, enhanced LTP induction and GluA1 phosphorylation were sustained up to 4 h after the stress. Treatment with 200 nM dexamethasone produced similar effects in the hippocampi of these mice, which supports the glucocorticoid receptor-mediated mechanism in these models. Collectively, our results demonstrated an alleviation of impaired LTP and synaptic plasticity in the hippocampal CA1 region following acute stress in the AD mouse models.


Assuntos
Doença de Alzheimer/metabolismo , Região CA1 Hipocampal/metabolismo , Potenciação de Longa Duração , Receptores de AMPA/metabolismo , Estresse Psicológico/metabolismo , Animais , Região CA1 Hipocampal/patologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Restrição Física/psicologia , Transmissão Sináptica
16.
Chembiochem ; 20(17): 2236-2240, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31270926

RESUMO

The soluble interleukin-2 receptor α (sIL-2Rα) is a broad indicator of clinical disease activity in various inflammatory diseases. Here we have developed, for the first time, a rapid, washing-free colorimetric aptasensor based on a sIL-2Rα aptamer (Kd =1.33 nm). The aptasensor was fabricated with Au nanoparticles (AuNPs) adsorbing sIL-2Rα aptamers. On addition of sIL-2Rα, the aptamers become desorbed from the AuNPs, and this in turn weakens the absorption corresponding to AuNP-catalyzed oxidation of ortho-phenylenediamine (oPD) with H2 O2 . The aptasensor was characterized by TEM imaging, ζ potential measurements, dynamic light scattering (DLS) analysis, and UV/Vis spectrometry, followed by further optimization. The fabricated sensor exhibited great analytical performance, with a linear range of 1 to 100 nm and a detection limit of 1 nm both in buffer and in spiked human serum within 25 min. Other proteins, such as bovine serum albumin (BSA), IL-17Rα, IL-5Rα, IL-13Rα2 , and CD166, showed negligible effects on the aptasensor. Thanks to the great advantages of the aptamers and AuNPs, this aptasensor provides a rapid, simple, and inexpensive process that might offer insights into various diagnostic applications of sIL-2Rα.


Assuntos
Aptâmeros de Nucleotídeos/química , Colorimetria/métodos , Ouro , Subunidade alfa de Receptor de Interleucina-2/análise , Nanopartículas Metálicas/química , Adsorção , Humanos , Subunidade alfa de Receptor de Interleucina-2/sangue , Limite de Detecção , Solubilidade
17.
Mol Neurobiol ; 56(12): 8076-8086, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31183806

RESUMO

Melanin-concentrating hormone (MCH) is a highly conserved neuropeptide known to exhibit important functions in the brain. Some studies have reported that MCH improves memory by promoting memory retention. However, the precise molecular mechanisms by which MCH enhances memory impairment have yet to be fully elucidated. In this study, MCH was administered to the scopolamine-induced memory-impaired mice via the nasal cavity to examine the acute effects of MCH and Alzheimer's disease (AD) mouse models to evaluate the chronic effects of MCH. MCH improved memory impairment in both models and reduced soluble amyloid beta in the cerebral cortex of APP/PS1 transgenic mice. In vitro assays also showed that MCH inhibits amyloid beta-induced cytotoxicity. Furthermore, MCH increased long-term potentiation (LTP) in the hippocampus of wild-type and 5XFAD AD mouse model. To further elucidate the mechanisms of the chronic effect of MCH, the levels of phosphorylated CREB and GSK3ß, and the expression of BDNF, TrkB and PSD95 were examined in the cerebral cortex and hippocampus. Our findings indicate that MCH might have neuroprotective effects via downstream pathways associated with the enhancement of neuronal synapses and LTP. This suggests a therapeutic potential of MCH for the treatment of neurodegenerative diseases such as AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Modelos Animais de Doenças , Hormônios Hipotalâmicos/administração & dosagem , Melaninas/administração & dosagem , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Hormônios Hipofisários/administração & dosagem , Administração Intranasal , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Cavidade Nasal/efeitos dos fármacos , Cavidade Nasal/metabolismo , Gravidez
18.
Sci Rep ; 9(1): 8918, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222110

RESUMO

Adiponectin is an adipokine that regulates apoptosis, glucose and lipid metabolism, and insulin sensitivity in metabolic diseases. As recent studies have associated changes in adipokines and other metabolites in the central nervous system with a risk for Alzheimer's disease (AD), we investigated the effects of adiponectin treatment on hippocampal cells in the 5XFAD mouse model of AD and neuronal SH-SY5Y cells under amyloid beta toxicity. Adiponectin treatment reduced levels of cleaved caspase 3 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) apoptosis signalling and decreased glycogen synthase kinase 3 beta (GSK3ß) activation. Moreover, adiponectin treatment triggered long-term potentiation in the hippocampi of 5XFAD mice, which was associated with reduced expression of N-methyl-D-aspartate and its receptor as well as surface expression of the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor. These findings suggest that adiponectin inhibits neuronal apoptosis and inflammatory mechanisms and promotes hippocampal long-term potentiation. Thus, adiponectin exhibits beneficial effect on hippocampal synaptic plasticity in Alzheimer's disease mouse model.


Assuntos
Adiponectina/fisiologia , Doença de Alzheimer/metabolismo , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Adiponectina/metabolismo , Animais , Caspase 3/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de AMPA/metabolismo
19.
BMC Bioinformatics ; 20(Suppl 10): 245, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31138119

RESUMO

BACKGROUND: The selection of reference genes is essential for quantifying gene expression. Theoretically they should be expressed stably and not regulated by experimental or pathological conditions. However, identification and validation of reference genes for human cancer research are still being regarded as a critical point, because cancerous tissues often represent genetic instability and heterogeneity. Recent pan-cancer studies have demonstrated the importance of the appropriate selection of reference genes for use as internal controls for the normalization of gene expression; however, no stably expressed, consensus reference genes valid for a range of different human cancers have yet been identified. RESULTS: In the present study, we used large-scale cancer gene expression datasets from The Cancer Genome Atlas (TCGA) database, which contains 10,028 (9,364 cancerous and 664 normal) samples from 32 different cancer types, to confirm that the expression of the most commonly used reference genes is not consistent across a range of cancer types. Furthermore, we identified 38 novel candidate reference genes for the normalization of gene expression, independent of cancer type. These genes were found to be highly expressed and highly connected to relevant gene networks, and to be enriched in transcription-translation regulation processes. The expression stability of the newly identified reference genes across 29 cancerous and matched normal tissues were validated via quantitative reverse transcription PCR (RT-qPCR). CONCLUSIONS: We reveal that most commonly used reference genes in current cancer studies cannot be appropriate to serve as representative control genes for quantifying cancer-related gene expression levels, and propose in this study three potential reference genes (HNRNPL, PCBP1, and RER1) to be the most stably expressed across various cancerous and normal human tissues.


Assuntos
Pesquisa Biomédica , Regulação Neoplásica da Expressão Gênica , Genes , Neoplasias/genética , Proteínas Adaptadoras de Transporte Vesicular , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Humanos , Glicoproteínas de Membrana , Reação em Cadeia da Polimerase em Tempo Real , Padrões de Referência , Reprodutibilidade dos Testes
20.
Exp Neurol ; 318: 22-31, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30981806

RESUMO

δ-Catenin is abundant in the brain and affects its synaptic plasticity. Furthermore, loss of δ-catenin is related to the deficits of learning and memory, mental retardation (cri-du-chat syndrome), and autism. A few studies about δ-catenin deficiency mice were performed. However, the effect of δ-catenin overexpression in the brain has not been investigated as yet. Therefore we generated a δ-catenin overexpressing mouse model. To generate a transgenic mouse model overexpressing δ-catenin in the brain, δ-catenin plasmid having a Thy-1 promotor was microinjected in C57BL/6 mice. Our results showed δ-catenin transgenic mice expressed higher levels of N-cadherin, ß-catenin, and p120-catenin than did wild type mice. Furthermore, δ-catenin transgenic mice exhibited better object recognition, better sociability, and lower anxiety than wild type mice. However, both mice groups showed a similar pattern in locomotion tests. Although δ-catenin transgenic mice show similar locomotion, they show improved sociability and reduced anxiety. These characteristics are opposite to the symptoms of autism or mental retardation, which are caused when δ-catenin is deficient. These results suggest that δ-catenin may alleviate symptoms of autism, Alzheimer's disease and mental retardation.


Assuntos
Ansiedade/metabolismo , Cateninas/metabolismo , Memória/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , delta Catenina
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