Increased levels of miR-124 in human dental pulp stem cells alter the expression of neural markers

Exploring Various Transfection Approaches and Their Applications in Studying the Regenerative Potential of Dental Pulp Stem Cells

Transfection is a contemporary approach for introducing foreign genetic material into target cells. The effective transport of genetic materials into cells is mostly influenced by (a) the characteristics of the genetic material (quantity and quality), (b) the transfection procedure (incubation time, ratio of the reagents to the introduced genetic material, and components of cell culture), and (c) targeted cells for transfection (cell origin and cell type). This review summarizes the findings of different studies focusing on various transfection approaches and their applications to explore the regenerative potential of dental pulp stem cells (DPSCs). Several databases, including Scopus, Google Scholar, and PubMed, were searched to obtain the literature for the current review. Different keywords were used as key terms in the search. Approximately 200 articles were retained after removing duplicates from different databases. Articles published in English that discussed different transfection approaches were included. Several sources were excluded because they did not meet the inclusion criteria. Approximately 70 relevant published sources were included in the final stage to achieve the study objectives. This review demonstrated that no single transfection system is applicable to all cases and the various cell types with no side effects. Further studies are needed to focus on optimizing process parameters, decreasing the toxicity and side effects of available transfection techniques, and increasing their efficiencies. Moreover, this review sheds light on the impact of using different valuable transfection approaches to investigate the regenerative potential of DPSCs.

Role of the Intermediate Filament Protein Peripherin in Health and Disease

Intermediate filaments are the most heterogeneous class among cytoskeletal elements. While some of them have been well-characterized, little is known about peripherin. Peripherin is a class III intermediate filament protein with a specific expression in the peripheral nervous system. Epigenetic modifications are involved in this cell-type-specific expression. Peripherin has important roles in neurite outgrowth and stability, axonal transport, and axonal myelination. Moreover, peripherin interacts with proteins involved in vesicular trafficking, signal transduction, DNA/RNA processing, protein folding, and mitochondrial metabolism, suggesting a role in all these processes. This review collects information regarding peripherin gene regulation, post-translational modifications, and functions and its involvement in the onset of a number of diseases.

Progress in the Study of Non-Coding RNAs in Multidifferentiation Potential of Dental-Derived Mesenchymal Stem Cells

For decades, the desire for tissue regeneration has never been quenched. Dental-derived mesenchymal stem cells (DMSCs), with the potential of self-renewal and multi-directional differentiation, have attracted much attention in this topic. Growing evidence suggests that non-coding RNAs (ncRNAs) can activate various regulatory processes. Even with a slight decrease or increase in expression, ncRNAs can weaken or even subvert cellular fate. Therefore, a systematic interpretation of ncRNAs that guide the differentiation of DMSCs into cells of other tissue types is urgently needed. In this review, we introduce the roles of ncRNAs in the differentiation of DMSCs, such as osteogenic differentiation, odontogenic differentiation, neurogenic differentiation, angiogenic differentiation and myogenic differentiation. Additionally, we illustrate the regulatory mechanisms of ncRNAs in the differentiation of DMSCs, such as epigenetic regulation, transcriptional regulation, mRNA modulation, miRNA sponges and signalling. Finally, we summarize the types and mechanisms of ncRNAs in the differentiation of DMSCs, such as let-7 family, miR-17∼92 family, miR-21, lncRNA H19, lncRNA ANCR, lncRNA MEG3, circRNA CDR1as and CircRNA SIPA1L1. If revealing the intricate relationship between ncRNAs and pluripotency of DMSCs 1 day, the application of DMSCs in regenerative medicine and tissue engineering will be improved. Our work could be an important stepping stone towards this future.

Neuronal Dynamics and miRNA Signaling Differ between SH-SY5Y APPSwe and PSEN1 Mutant iPSC-Derived AD Models upon Modulation with miR-124 Mimic and Inhibitor

Neuronal miRNA dysregulation may have a role in the pathophysiology of Alzheimer's disease (AD). miRNA(miR)-124 is largely abundant and a critical player in many neuronal functions. However, the lack of models reliably recapitulating AD pathophysiology hampers our understanding of miR-124's role in the disease. Using the classical human SH-SY5Y-APP695 Swedish neuroblastoma cells (SH-SWE) and the PSEN1 mutant iPSC-derived neurons (iNEU-PSEN), we observed a sustained upregulation of miR-124/miR-125b/miR-21, but only miR-124 was consistently shuttled into their exosomes. The miR-124 mimic reduced APP gene expression in both AD models. While miR-124 mimic in SH-SWE neurons led to neurite outgrowth, mitochondria activation and small Aβ oligomer reduction, in iNEU-PSEN cells it diminished Tau phosphorylation, whereas miR-124 inhibitor decreased dendritic spine density. In exosomes, cellular transfection with the mimic predominantly downregulated miR-125b/miR-21/miR-146a/miR-155. The miR-124 inhibitor upregulated miR-146a in the two experimental cell models, while it led to distinct miRNA signatures in cells and exosomes. In sum, though miR-124 function may be dependent on the neuronal AD model, data indicate that keeping miR-124 level strictly controlled is crucial for proper neuronal function. Moreover, the iNEU-PSEN cellular model stands out as a useful tool for AD mechanistic studies and perhaps for the development of personalized therapeutic strategies.

Bioinformatics Accelerates the Major Tetrad: A Real Boost for the Pharmaceutical Industry

With advanced technology and its development, bioinformatics is one of the avant-garde fields that has managed to make amazing progress in the pharmaceutical-medical field by modeling the infrastructural dimensions of healthcare and integrating computing tools in drug innovation, facilitating prevention, detection/more accurate diagnosis, and treatment of disorders, while saving time and money. By association, bioinformatics and pharmacovigilance promoted both sample analyzes and interpretation of drug side effects, also focusing on drug discovery and development (DDD), in which systems biology, a personalized approach, and drug repositioning were considered together with translational medicine. The role of bioinformatics has been highlighted in DDD, proteomics, genetics, modeling, miRNA discovery and assessment, and clinical genome sequencing. The authors have collated significant data from the most known online databases and publishers, also narrowing the diversified applications, in order to target four major areas (tetrad): DDD, anti-microbial research, genomic sequencing, and miRNA research and its significance in the management of current pandemic context. Our analysis aims to provide optimal data in the field by stratification of the information related to the published data in key sectors and to capture the attention of researchers interested in bioinformatics, a field that has succeeded in advancing the healthcare paradigm by introducing developing techniques and multiple database platforms, addressed in the manuscript.

Upregulation of Neuroprogenitor and Neural Markers via Enforced miR-124 and Growth Factor Treatment

Previous studies have shown that miR-124 plays an important role in the development of auditory neurons, which are degenerated in the sensorineural hearing loss. However, whether the combined use of miR-124 and growth factors can increase the expression of neural related markers in human dental pulp stem cells has been remained unknown so far. In this study, human dental pulp stem cells were transfected with miR-124 following treatment with brain-derived neurotrophic factor or epidermal growth factor/basic fibroblast growth factor. The expression of some neural related markers (nestin, SOX2, β-tubulin III, MAP2, and peripherin) was analyzed in two groups by qRT-PCR or immunofluorescence. Cellular treatment resulted in morphological changes including neurosphere-like colonies formation. Nestin and SOX2 were up-regulated, and MAP2 and peripherin were down-regulated in dental pulp stem cells transfected by miR-124 following treatment with brain-derived neurotrophic factor. Replacement of brain-derived neurotrophic factor with epidermal growth factor/ basic fibroblast growth factor resulted in the up-regulation of nestin, MAP2, peripherin, and β-tubulin III and down-regulation of SOX2. The expression of SOX2 and nestin was also confirmed by immunofluorescence. The combination of miR-124 and growth factors would provide a promising starting point for upregulating the neural progenitor markers in human dental pulp stem cells.

In silico and in vitro effects of the I30T mutation on myelin protein zero instability in the cell membrane

Charcot-Marie-Tooth (CMT) diseases are a heterogeneous group of genetic peripheral neuropathies caused by mutations in a variety of genes, which are involved in the development and maintenance of peripheral nerves. Myelin protein zero (MPZ) is expressed by Schwann cells, and MPZ mutations can lead to primarily demyelinating polyneuropathies including CMT type 1B. Different mutations demonstrate various forms of disease pathomechanisms, which may be beneficial in understanding the disease cellular pathology. Our molecular dynamics simulation study on the possible impacts of I30T mutation on the MPZ protein structure suggested a higher hydrophobicity and thus lower stability in the membranous structures. A study was also conducted to predict native/mutant MPZ interactions. To validate the results of the simulation study, the native and mutant forms of the MPZ protein were separately expressed in a cellular model, and the protein trafficking was chased down in a time course pattern. In vitro studies provided more evidence on the instability of the MPZ protein due to the mutation. In this study, qualitative and quantitative approaches were adopted to confirm the instability of mutant MPZ in cellular membranes.