Research progress on establishment and evaluation methods of AD cellular models / 中国药理学通报

Cellular model is one of the effective methods for studying Alzheimer's disease (AD). In recent years,the establishment of AD cellular model to simulate the pathogenesis of AD has become the focus of scholars. By sorting out the relevant literature of AD cellular models in recent years and further exploring pathogenesis of A D, this paper summarizes and systematically analyzes the establishment methods, evaluation indices and model characteristics of AD cellular models, in order to provide ideas and reference for the rational construction and in-depth study of AD cellular models.

La agregación de TDP-43 como posible blanco terapéutico contra la Esclerosis Lateral Amiotrófica / TDP-43 aggregation as a possible therapeutic target for Amyotrophic Lateral Sclerosis / Agregação de TDP-43 como um possível alvo terapêutico para a Esclerose Lateral Amiotrófica

Los agregados de TDP-43 representan una de las característica histopatológicas más importantes de varias enfermedades neurodegenerativas, entre las que se incluye la Esclerosis Lateral Amiotrófica (ELA). TDP-43 está localizada principalmente en el núcleo. Sin embargo, los pacientes afectados por ELA presentan agregados de TDP-43 en el citoplasma de las neuronas comprometidas, con lo que se despoja al núcleo de TDP-43 funcional. Aún se desconoce si la degeneración causada por la agregación de TDP-43 es debida a una toxicidad intrínseca de los agregados o a la pérdida de función de TDP-43 como consecuencia del vaciamiento del núcleo. Varias investigaciones, incluidas las de estos autores, indican que la pérdida de función es el factor fundamental responsable de la neurodegeneración observada en presencia de inclusiones de TDP-43. Por otro lado, aún no existen tratamientos efectivos para la ELA. Por lo tanto, es de crucial importancia conocer las bases moleculares que conllevan al desarrollo de la enfermedad, con el objetivo de encontrar posibles estrategias terapéuticas. Para ello, estos autores han desarrollado un modelo celular capaz de imitar la agregación de TDP-43 y sus consecuencias. Finalmente, se ha utilizado este modelo para analizar el efecto de diferentes compuestos capaces de degradar los agregados de TDP-43 y se ha demostrado que esta podría ser una estrategia terapéutica válida para la ELA.

TDP-43 inclusions are important histopathological features of various neurodegenerative disorders, including Amyotrophic Lateral Sclerosis (ALS). TDP-43 is mainly a nuclear protein, but it shuffles from the nucleus to the cytoplasm. In patients’ brains, TDP-43 is retained in the cytoplasm of the affected motorneurons to form insoluble aggregates, which results in TDP-43 nuclear clearance. There is still no consensus whether TDP-43-mediated neurodegeneration results from a gain or loss of function of the protein or a combination of both. The work from several laboratories, including this, points towards a strong loss of function component. On the other hand, there is no effective treatment or cure for ALS. Thus, there is obviously a need to find new therapeutic strategies for ALS. In order to gain new insights into the molecular mechanism of the disease, and with the aim of looking for new methodologies that can revert it, a cellular model of TDP-43 aggregation that can mimic the phenotypic consequences found in ALS patients has been developed. Finally, this model was used to search for compounds that can dissolve these aggregates, and it was shown that the clearance of TDP-43 aggregates could be a therapeutic strategy for ALS.

Os agregados proteicos TDP-43 são características histopatológicas importantes de muitas doenças neurodegenerativas, incluindo a Esclerose Lateral Amiotrófica (ALS). A proteína TDP-43 se localiza principalmente no núcleo, porém nos cérebros de indivíduos afetados, a proteína TDP-43 fica retida no citoplasma dos neurônios motores, o que leva a formação de agregados insolúveis, resultando em deposição nuclear. Ainda não existe um consenso se a neurodegeneração mediada por TDP43 é causada por ganho ou perda da função da proteína ou uma combinação de ambos. O trabalho de muitos laboratórios, bem como este trabalho, apontam para uma forte perda da função da proteína. Por outro lado, não existe um tratamento efetivo ou cura para a ALS. Portanto, existe uma grande necessidade de identificar novos tratamentos para a ALS. Para entender o mecanismo molecular da doença, e com o objetivo de identificar novas metodologias para reverter a doença, desenvolvemos o modelo celular de agregados de TDP-43, o qual mimetiza as consequências fenotípicas encontradas em pacientes com ALS. Por fim, utilizamos esse modelo para identificar compostos que podem dissolver os agregados, e demonstramos que a liberação de inclusões de TDP-43 poderiam ser usados como tratamentos para a ALS.

Induced Pluripotent Stem Cells as a Novel Tool in Psychiatric Research

Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) provides a valuable opportunity to study neurodevelopmental and neurodegenerative psychiatric diseases by offering an unlimited source for patient-specific neuronal and glial cells. The present review focuses on the recent advancements in modeling psychiatric disorders such as Phelan-McDermid syndrome, Timothy syndrome, Rett syndrome, schizophrenia, bipolar disorder, and dementia. The treatment effects identified in studies on iPSCs using known therapeutic compounds are also summarized in this review. Here we discuss validation of cellular models and explore iPSCs as a novel drug screening tool. Although there are several limitations associated with the current methods used to study mental disorders, using iPSCs as a model system provides the advantage of rewinding and reviewing the development and degeneration of human neural cells.

Mir-190b negatively contributes to the Trypanosoma cruzi- infected cell survival by repressing PTEN protein expression

Chagas disease, which is caused by the intracellular protozoanTrypanosoma cruzi, is a serious health problem in Latin America. The heart is one of the major organs affected by this parasitic infection. The pathogenesis of tissue remodelling, particularly regarding cardiomyocyte behaviour after parasite infection, and the molecular mechanisms that occur immediately following parasite entry into host cells are not yet completely understood. Previous studies have reported that the establishment of parasitism is connected to the activation of the phosphatidylinositol-3 kinase (PI3K), which controls important steps in cellular metabolism by regulating the production of the second messenger phosphatidylinositol-3,4,5-trisphosphate. Particularly, the tumour suppressor PTEN is a negative regulator of PI3K signalling. However, mechanistic details of the modulatory activity of PTEN on Chagas disease have not been elucidated. To address this question, H9c2 cells were infected with T. cruzi Berenice 62 strain and the expression of a specific set of microRNAs (miRNAs) were investigated. Our cellular model demonstrated that miRNA-190b is correlated to the decrease of cellular viability rates by negatively modulating PTEN protein expression in T. cruzi-infected cells.

Proceedings in atherosclerotic pharmacological models / 国际药学研究杂志

Atherosclerosis, a common cardiovascular and cerebrovascular disease, has attracted more and more attention world wide in recent years. Investigation of the pathogenesis of atherosclerosis is important for the prevention and treatment of atherosclerosis. Choice and establishment of experimental models play a vital role in these investigations. A proper experimental model not only can reduce costs and labors, but also reflect the nature of the experimental phenomenon which helps to achieve adequate experimental purposes. In this review, we introduce the proceedings in currently used animal and cellular models of atherosclerosis to provide reference for atherosclerosis researches.

Suppression subtraction hybridization in screening of differentially expressed genes in radiation-induced malignant transformation cellular model / 第二军医大学学报

Objective: To screen for the differentially expressed genes during irradiation-induced malignant transformation of human bronchus epithelium cells (BEAS-2B). Methods: Suppression subtraction hybridization (SSH) was used to construct a subtracted cDNA library of differentially expressed genes during irradiation-induced malignant transformation of BEAS-2B cells. Then the subtracted library was screened by PCR and the differential fragments were sequenced and analyzed with BLAST. Fluorescent real-time quantitative PCR was used to investigate some of the differentially expressed genes. The new EST was registered in GenBank. Results: Then 40 clones were chosen to be sequenced from the library of increased expression and decreased expression respectively according to the length of insertion element. Totally 73 sequences were obtained from the 80 sequenced clones. Forty-one sequences were decreased in the transformed cells; BLAST analysis indicated that there were 6 known sequences, 20 unknown sequences, 7 void sequences and 8 repeated sequences. Thirty-two sequences were increased in the transformed cells; Blast analysis indicated that there were 14 known sequences, 9 unknown sequences, and 9 repeated sequences. Fluorescent quantitative PCR revealed that, compared with control group, the expression of MY06, HACE1, ZNF143, and HNRPH1 were significantly increased in the radiation transforming group, with their mRNAs increased by 3.49, 29.38, 12.99 and 5.00 folds, respectively. Compared with control group, the expression of PCBP2, RPL15, and TCERG1 in the radiation transforming group was significantly decreased, with their mRNAs decreased by 1.89,48.77 and 11.95 folds, respectively. The 29 unknown sequences were registered in the GenBank (ID: EB643220-EB643248). Conclusion: The cDNA library has been successfully established for malignant transformation cellular model by suppression subtractive hybridization; the library includes a number of unknown genes. The increased gene ZNF143 is associated with cell proliferation and cell division. TCERG1, as an assistant transcription activation factor, plays an important role in the mRNA transcription and later modification. PCBP2, a Polyc connection protein, plays a modulating role in protein translation. These genes have not been reported in the radiation carcinogenicity.

Protective effect of ?-scretase substrate-base peptide on cellular model of Alzheimer's disease / 西安交通大学学报(医学版)

Objective To study the effect of ?-scretase substrate-base peptide(BACEsp) on cellular model of Alzheimer's disease(AD).Methods The cellular model of AD established with neuroblastoma cell SK-N-SH induced by amyloid precursor protein(APP) was infected with the supernatants including recombinant retrovirus pLXSN-BACEsp.MTT assay was used to test cell viability and immunocytochemistry was used to observe APP expresion in cells before and after BACEsp treatment.Results Cell viability and APP expression in the cells that had been first infected by recombinant retrovirus pLXSN-BACEsp were apparently higher than those only transfected by APP and last infected by recombinant retrovirus pLXSN-BACEsp.Conclusion BACEsp has an obviously protective effect on APP-induced neuron toxicity of cellular model of AD.