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Background: Neuronal loss occurs early and is recognized as a hallmark of Alzheimer's disease (AD). Promoting neurogenesis is an effective treatment strategy for neurodegenerative diseases. Traditional Chinese herbal medicines serve as a rich pharmaceutical source for modulating hippocampal neurogenesis. Objective: Gallic acid (GA), a phenolic acid extracted from herbs, possesses anti-inflammatory and antioxidant properties. Therefore, we aimed to explore whether GA can promote neurogenesis and alleviate AD symptoms. Methods: Memory in mice was assessed using the Morris water maze, and protein levels were examined via western blotting and immunohistochemistry. GA's binding site in the promoter region of transcription regulator nuclear factor erythroid 2-related factor 2 (Nrf2) was calculated using AutoDock Vina and confirmed by a dual luciferase reporter assay. Results: We found that GA improved spatial memory by promoting neurogenesis in the hippocampal dentate gyrus zone. It also improved synaptic plasticity, reduced tau phosphorylation and amyloid-ß concentration, and increased levels of synaptic proteins in APP/PS1 mice. Furthermore, GA inhibited the activity of glycogen synthase kinase-3ß (GSK-3ß). Bioinformatics tools revealed that GA interacts with several amino acid sites on GSK-3ß. Overexpression of GSK-3ß was observed to block the protective effects of GA against AD-like symptoms, while GA promoted neurogenesis via the GSK-3ß-Nrf2 signaling pathway in APP/PS1 mice. Conclusions: Based on our collective findings, we hypothesize that GA is a potential pharmaceutical agent for alleviating the pathological symptoms of AD.
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This study was designed to illustrate the function and role of PCAT1 in CCA. The relative expression was confirmed by RT-qPCR and western blot. The biological function of PCAT1 was evaluated by CCK8, EdU, colony formation, wound healing, transwell, and subcutaneous tumor formation assays. Protein levels of EMT markers were measured by western blot. The binding relationship was predicted by JASPAR and starBase. The binding of YY1 to PCAT1 promoter was assessed by ChIP and luciferase reporter. The binding capacity between miR-216a-3p and PCAT1 as well as BCL3 was assessed by luciferase reporter and AGO2-RIP assays. In this study, we found that PCAT1 was up-regulated in CCA tissues and cells, and the PCAT1 overexpression was associated with poor prognosis. Moreover, PCAT1 was assessed as an independent risk factor of prognosis for CCA patients. Amplified PCAT1 was found to promote tumor proliferation, migration, invasion and EMT process, whereas PCAT1 knockdown inhibited these malignant phenotypes. Mechanistically, PCAT1 was predominantly localized in the cytoplasm and competitively bound miR-216a-3p to increase BCL3 expression. In addition, PCAT1 was activated by transcription factor YY1. This study revealed that PCAT1 acted as an oncogene in CCA, and the YY1/PCAT1/miR-216a-3p/BCL3 axis exhibited critical functions in CCA progression.
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Proteína 3 do Linfoma de Células B/metabolismo , Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Regulação para Cima , Fator de Transcrição YY1/metabolismo , Proteína 3 do Linfoma de Células B/genética , Neoplasias dos Ductos Biliares/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Colangiocarcinoma/patologia , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Longo não Codificante/genética , Fator de Transcrição YY1/genéticaRESUMO
Metabolic disorders are major clinical challenges of health that are progressing globally. A concurrence of metabolic disorders such as obesity, insulin resistance, atherogenic dyslipidemia, and systematic hypertension leads to metabolic syndrome. Over the past years, the metabolic syndrome leads to a five- and two-fold rise in diabetes mellitus type II and cardiovascular diseases. Natural products specifically plant extracts have insulin-sensitizing, anti-inflammatory, and antioxidant properties and are also considered as an alternative option due to few adverse effects. Nanotechnology is one of the promising strategies, which improves the effectiveness of treatment and limits side effects. This review mainly focuses on plant extract-based nanosystems in the management of the metabolic syndrome. Numerous nano-drug delivery systems, i.e., liposomes, hydrogel nanocomposites, nanoemulsions, micelles, solid lipid, and core-shell nanoparticles, have been designed using plant extracts. It has been found that most of the nano-formulations successfully reduced oxidative stress, insulin resistance, chronic inflammation, and lipid profile in in vitro and in vivo studies as plant extracts interfere with the pathways of metabolic syndrome. Thus, these novel plant-based nanosystems could act as a promising candidate for clinical applications.
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Protein misfolding and aggregation are associated with amyloidosis. The toxic aggregation of amyloid-ß 1-42 (Aß42) may disrupt cell membranes and lead to cell death and is thus regarded as a contributing factor in Alzheimer's disease (AD). 1,4-naphthoquinone (NQ) has been shown to exhibit strong anti-aggregation effects on amyloidogenic proteins such as insulin and α-synuclein; however, its high toxicity and poor solubility limit its clinical application. Menadione sodium bisulfite (MSB, also known as vitamin K3), is used clinically in China to treat hemorrhagic diseases caused by vitamin K deficiency and globally as a vitamin K supplement. We hypothesized that MSB could inhibit amyloid formation since its backbone structure is similar to NQ. To test our hypothesis, we first investigated the effects of MSB on Aß42 amyloid formation in vitro. We found that MSB inhibited Aß42 amyloid formation in a dose dependent manner, delayed the secondary structural conversion of Aß42 from random coil to ordered ß-sheet, and attenuated the ability of Aß42 aggregates to disrupt membranes; moreover, the quinone backbone rather than lipophilicity is esstial for the inhibitory effects of MSB. Next, in cells expressing a pathogenic APP mutation (Osaka mutation) that results in the formation of intraneuronal Aß oligomers, MSB inhibited the intracellular aggregation of Aß. Moreover, MSB treatment significantly extended the life span of Caenorhabditis elegans CL2120, a strain that expresses human Aß42. Together, these results suggest that MSB and its derivatives may be further explored as potential therapeutic agents for the prevention or treatment of AD.
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Peptídeos beta-Amiloides/química , Animais Geneticamente Modificados/crescimento & desenvolvimento , Caenorhabditis elegans/crescimento & desenvolvimento , Fragmentos de Peptídeos/química , Agregação Patológica de Proteínas/prevenção & controle , Vitamina K 3/farmacologia , Vitaminas/farmacologia , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Humanos , Longevidade , Fragmentos de Peptídeos/efeitos dos fármacosRESUMO
The most notable and unique property of pectin is the ability to form gel; thus, many biological applications of pectin are based on its gelation properties. Pectin isolated from different plant cell walls may differ in molecular structure and distribution pattern, which may result in different gelling and function properties. In this work, we investigated the chemical characteristics, gelation properties, and biological application of calcium pectate (CaP) prepared using apple (AP) or citrus pectin (CP). These two types of pectins exhibited similar molecular parameters and glycosidic bone structure; however, there was a difference in the composition proportion of single monosaccharide. In addition, it was found that it was relatively easier to form CaP beads with CP compared with AP. Moreover, CP exhibited a higher binding capability with Ca2+. The morphological study suggests that CP-CaP beads have a rough wrinkle structure on the surface, which might benefit mass transfer and cell proliferation. Moreover, although there are some differences in the viability and proliferation of cells encapsulated in the AP-CaP and CP-CaP beads, both can be used for cell encapsulation.
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Fenômenos Químicos , Citrus/química , Malus/química , Pectinas/química , Compostos Fitoquímicos/química , Calorimetria , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Espectroscopia de Ressonância Magnética , Microesferas , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , TermodinâmicaRESUMO
Although numerous studies have reported the influence of extremely low frequency magnetic field (ELF-MF) exposure on human health, its effects on cognitive deficits in Alzheimer's disease (AD) have remained under debate. Moreover, the influence of ELF-MF on hyperphosphorylated tau, which is one of the most common pathological hallmarks of AD, has not been reported to date. Therefore, transgenic mice (3xTg) were used in the present study. 3xTg mice, which express an APP/PS1 mutation combined with a tau (P301L) mutation and that develop cognitive deficits at 6 months of age, were subjected to ELF-MF (50Hz, 500µT) exposure or sham exposure daily for 3 months. We discovered that ELF-MF exposure ameliorated cognitive deficits and increased synaptic proteins in 3xTg mice. The protective effects of ELF-MF exposure may have also been caused by the inhibition of apoptosis and/or decreased oxidative stress levels that were observed in the hippocampus tissues of treated mice. Furthermore, tau hyperphosphorylation was decreased in vivo because of ELF-MF exposure, and this decrease was induced by the inhibition of GSK3ß and CDK5 activities and activation of PP2Ac. We are the first to report that exposure to ELF-MF can attenuate tau phosphorylation. These findings suggest that ELF-MF exposure could act as a valid therapeutic strategy for ameliorating cognitive deficits and attenuating tau hyperphosphorylation in AD.