RESUMO
Cadmium (Cd) as a ubiquitous toxic heavy metal in the environment, causes severe hazards to human health, such as cellular stress and organ injury. Selenium (Se) was reported to reduce Cd toxicity and the mechanisms have been intensively studied so far. However, it is not yet crystal clear whether the protective effect of Se against Cd-induced cytotoxicity is related to selenoproteins in nerve cells or not. In this study, we found that Cd inhibited selenoprotein thioredoxin reductase 1 (TrxR1; TXNRD1) and decreased the expression level of TrxR1, resulting in cellular oxidative stress, and Se supplements ameliorated Cd-induced cytotoxicity in SH-SY5Y cells. Mechanistically, the detoxification of Se against Cd is attributed to the increase of the cellular TrxR activity and upregulated TrxR1 protein level, culminating in strengthened antioxidant capacity. Results showed that Se supplements attenuated the ROS production and apoptosis in SH-SY5Y cells, and significantly mitigated Cd-induced SH-SY5Y cell death. This study may be a valuable reference for shedding light on the mechanism of Cd-induced cytotoxicity and the role of TrxR1 in Se-mitigated cytotoxicity of Cd in neuroblast cells, which may be helpful for understanding the therapeutic potential of Cd and Se in treating or preventing neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD).
Assuntos
Neuroblastoma , Selênio , Humanos , Cádmio/toxicidade , Cádmio/metabolismo , Regulação para Baixo , Espécies Reativas de Oxigênio/metabolismo , Ácido Selenioso/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Tiorredoxina Redutase 1/metabolismo , Regulação para CimaRESUMO
Lipid droplets (LDs) are intracellular droplets containing phospholipids and neutral lipids. It is well known that LDs are organelles with a rich proteome. In the nervous system, these droplets may play an important role in maintaining the normal physiological function of nerve cells. Moreover, LDs may relate to the neurodegenerative disorders, such as Alzheimer's disease (AD). However, more information is still needed about the function of LDs. In the study presented here, we identified the protein composition of mouse neuroblastoma (N2a) cell LDs using immunodetection and high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS). Seventy three LDs proteins were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to investigate the potential functions of these proteins. Subsequently, the relationships among the proteins were analyzed by constructing a protein-protein interaction (PPI) network. N2a cell LDs contain multiple Rab GTPases, chaperones, and proteins involved in ubiquitination and transport. Some of these proteins were known to modulate LD formation and were related to the function of nerve cells. This work presents the proteome of N2a cell LDs and will help to identify the role of LDs in the nervous system.
Assuntos
Neuroblastoma , Proteômica , Animais , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Camundongos , Proteoma/análise , Proteômica/métodosRESUMO
The protective innate immune response of ß-amyloid peptide (Aß) has been indicated as a risk factor for Alzheimer's disease (AD) due to the rapid amyloidosis. In order to obtain molecular-level insights into the protective and pathogenic roles of Aß, the binding modes between Aß1-42 and the envelop glycoprotein D (gD) of Herpes simplex virus-1 (HSV-1)/Aß1-42 were theoretically investigated by using molecular docking, molecular dynamics (MD) simulations and binding free energy decomposition methods in the present study. The Aß1-42 stably binds to the envelop gD via intermolecular hydrogen bonds and van der Waals (vdW) interactions. The Aß1-42 acquires its equilibrium with higher fluctuation amplitude and a better structured C-terminal in the HSV-1 gD-Aß1-42 complex comparing to that in the Aß1-42-Aß1-42 complex. The amino acid residues of Aß1-42 involved in the formation of the Aß1-42 dimer are fully free and accessible in the HSV-1 gD-Aß1-42 complex. It is favorable for the Aß1-42 monomer to interact with the HSV-1 gD-Aß1-42 complex. It may be responsible for the rapid amyloidosis which entraps the herpesvirus as well as causing AD.