Human Embryonic Stem Cell-Derived Wilson's Disease Model for Screening Drug Efficacy

Decoding Neurodegeneration: A Comprehensive Review of Molecular Mechanisms, Genetic Influences, and Therapeutic Innovations

Neurodegenerative disorders often acquire due to genetic predispositions and genomic alterations after exposure to multiple risk factors. The most commonly found pathologies are variations of dementia, such as frontotemporal dementia and Lewy body dementia, as well as rare subtypes of cerebral and cerebellar atrophy-based syndromes. In an emerging era of biomedical advances, molecular-cellular studies offer an essential avenue for a thorough recognition of the underlying mechanisms and their possible implications in the patient's symptomatology. This comprehensive review is focused on deciphering molecular mechanisms and the implications regarding those pathologies' clinical advancement and provides an analytical overview of genetic mutations in the case of neurodegenerative disorders. With the help of well-developed modern genetic investigations, these clinically complex disturbances are highly understood nowadays, being an important step in establishing molecularly targeted therapies and implementing those approaches in the physician's practice.

A Systematic Review and Meta-Analysis of the R778L Mutation in ATP7B With Wilson Disease in China

BACKGROUND

Wilson disease (WD) is a hereditary disorder of copper metabolism, caused by mutations in the ATP7B gene. There are more than 1000 pathogenic variants identified in ATP7B. R778L is the most common ATP7B mutation in China.

METHODS

To estimate whether R778L is associated with the onset age of WD and other clinical variables. Genotyping results of ATP7B gene were collected in our 22 patients with WD. We then conducted a systematic review and meta-analysis in databases, using the keywords Wilson disease and R778L mutation.

RESULTS

After the screening, a total of 23 studies were included, including 3007 patients with WD. Patients with R778L mutation presented at an earlier age (standardized mean difference [SMD] = -0.18 [95% confidence interval, -0.28 to 0.08], P = 0.0004) and had lower ceruloplasmin concentration (SMD = -0.21 [95% confidence interval, -0.40 to -0.02], P = 0.03) than the patients without the R778L mutation. However, sex (odds ratio [OR] = 1.07 [95% confidence interval, 0.89 to 1.29], P = 0.32) and first presentation were not associated with R778L mutation in WD (hepatic: OR = 1.37 [95% confidence interval, 0.87 to 2.16, P = 0.17; neurological: OR = 0.79 [95% confidence interval, 0.48 to 1.30, P = 0.35; mix: OR = 1.04 [95% confidence interval, 0.42 to 2.53, P = 0.87; asymptomatic/others: OR = 1.98 [95% confidence interval, 0.49 to 7.96, P = 0.34).

CONCLUSIONS

Our results indicated that the R778L mutation is associated with an earlier presentation and lower ceruloplasmin concentration in China.

Research and Therapeutic Approaches in Stem Cell Genome Editing by CRISPR Toolkit

The most widely used genome editing toolkit is CRISPR (clustered regularly interspaced short palindromic repeats). It provides the possibility of replacing and modifying DNA and RNA nucleotides. Furthermore, with advancements in biological technology, inhibition and activation of the transcription of specific gene(s) has become possible. Bioinformatics tools that target the evolution of CRISPR-associated protein 9 (Cas9) turn this protein into a vehicle that is specific for a DNA or RNA region with single guide RNA (sgRNA). This toolkit could be used by researchers to investigate the function of stem cell gene(s). Here, in this review article, we cover recent developments and applications of this technique in stem cells for research and clinical purposes and discuss different CRISPR/Cas technologies for knock-out, knock-in, activation, or inhibition of gene expression. Additionally, a comparison of several deliveries and off-target detecting strategies is discussed.

Stem Cell-Based Therapeutic Approaches in Genetic Diseases

Stem cells, which can self-renew and differentiate into different cell types, have become the keystone of regenerative medicine due to these properties. With the achievement of superior clinical results in the therapeutic approaches of different diseases, the applications of these cells in the treatment of genetic diseases have also come to the fore. Foremost, conventional approaches of stem cells to genetic diseases are the first approaches in this manner, and they have brought safety issues due to immune reactions caused by allogeneic transplantation. To eliminate these safety issues and phenotypic abnormalities caused by genetic defects, firstly, basic genetic engineering practices such as vectors or RNA modulators were combined with stem cell-based therapeutic approaches. However, due to challenges such as immune reactions and inability to target cells effectively in these applications, advanced molecular methods have been adopted in ZFN, TALEN, and CRISPR/Cas genome editing nucleases, which allow modular designs in stem cell-based genetic diseases' therapeutic approaches. Current studies in genetic diseases are in the direction of creating permanent treatment regimens by genomic manipulation of stem cells with differentiation potential through genome editing tools. In this chapter, the stem cell-based therapeutic approaches of various vital genetic diseases were addressed wide range from conventional applications to genome editing tools.

The Effect of Disulfiram and Copper on Cellular Viability, ER Stress and ALDH Expression of Human Meningioma Cells

(1) Background: Meningiomas are the most common intracranial tumors in adults; currently there is no effective chemotherapy for malignant meningiomas. The effect of disulfiram (DSF)/Copper (Cu) on meningiomas remains unclear; (2) Methods: The impact of DSF/Cu on cell viability of meningioma adhesion cells (MgACs) and sphere cells (MgSCs) was assessed via MTS assay. The effects of DSF/Cu on intracellular Cu levels, cell senescence, and apoptosis were analyzed using CopperGreen, C12FDG, and Annexin V assays. Intracellular ALDH isoform expression and canonical pathway expression after DSF/Cu treatment were analyzed using mRNA microarray and Ingenuity Pathway Analysis, with further verification through qRT-PCR and immunoblotting; (3) Results: The viability of MgACs and MgSCs were inhibited by DSF/Cu. DSF/Cu increased intracellular Cu levels and cellular senescence. DSF/Cu also induced ER stress in MgACs and activated the PERK/eIF2 pathway for further adaptive response, apoptosis, and autophagy. Finally, DSF/Cu inhibited the expression of different ALDH isoforms in MgACs and MgSCs; (4) Conclusions: DSF/Cu exerts cytotoxic effects against both meningioma cells and stem-like cells and has treatment potential for meningioma.

The potential and limitations of intrahepatic cholangiocyte organoids to study inborn errors of metabolism

Inborn errors of metabolism (IEMs) comprise a diverse group of individually rare monogenic disorders that affect metabolic pathways. Mutations lead to enzymatic deficiency or dysfunction, which results in intermediate metabolite accumulation or deficit leading to disease phenotypes. Currently, treatment options for many IEMs are insufficient. Rarity of individual IEMs hampers therapy development and phenotypic and genetic heterogeneity suggest beneficial effects of personalized approaches. Recently, cultures of patient-own liver-derived intrahepatic cholangiocyte organoids (ICOs) have been established. Since most metabolic genes are expressed in the liver, patient-derived ICOs represent exciting possibilities for in vitro modeling and personalized drug testing for IEMs. However, the exact application range of ICOs remains unclear. To address this, we examined which metabolic pathways can be studied with ICOs and what the potential and limitations of patient-derived ICOs are to model metabolic functions. We present functional assays in patient ICOs with defects in branched-chain amino acid metabolism (methylmalonic acidemia), copper metabolism (Wilson disease), and transporter defects (cystic fibrosis). We discuss the broad range of functional assays that can be applied to ICOs, but also address the limitations of these patient-specific cell models. In doing so, we aim to guide the selection of the appropriate cell model for studies of a specific disease or metabolic process.

In Vitro Generation of Heart Field Specific Cardiomyocytes

Myocardial infarction (MI) can lead to irreversible loss of cardiomyocytes (CMs), primarily localized to the left ventricle (LV) of the heart. The CMs of the LV are predominantly derived from first heart field (FHF) progenitors, whereas the majority of CMs within the right ventricle originate from the second heart field (SHF) during early cardiogenesis. Human embryonic stem cells (hESCs) serve as a valuable source of CMs for understanding early cardiac development and lineage commitment of CMs within these two heart fields that ultimately enable the development of more effective candidates for cell therapy. An ideal candidate may be FHF CMs that share the same ontogeny with the LV CMs that die after MI. We previously generated a double reporter hESC line that utilizes two important cardiac transcription factors, TBX5 and NKX2-5. TBX5 marks FHF progenitors and CMs, while NKX2-5 is expressed in nearly all myocytes of the developing heart. Here, we describe a step-by-step approach to efficiently generate FHF and SHF CMs using this double reporter hESC line. In addition, this approach can be applied to any non-genetically modified hESC lines to enrich FHF and SHF CMs. Obtaining enriched populations of these two CM subtypes provides a platform for downstream comparative analyses and in vitro studies to facilitate a deeper understanding of cardiovascular lineage commitment and the development of more effective candidates for cell therapy to treat diseases or defects that affect specific regions of the heart.

Human Pluripotent Stem Cell-Derived Hepatocyte-Like Cells and Organoids for Liver Disease and Therapy

Liver disease is a global health issue that has caused an economic burden worldwide. Organ transplantation is the only effective therapy for end-stage liver disease; however, it has been hampered by a shortage of donors. Human pluripotent stem cells (hPSCs) have been widely used for studying liver biology and pathology as well as facilitating the development of alternative therapies. hPSCs can differentiate into multiple types of cells, which enables the generation of various models that can be applied to investigate and recapitulate a range of biological activities in vitro. Here, we summarize the recent development of hPSC-derived hepatocytes and their applications in disease modeling, cell therapy, and drug discovery. We also discuss the advantages and limitations of these applications and critical challenges for further development.

CRISPR-Cas9 based genome editing for defective gene correction in humans and other mammals

Clustered regularly interspaced short palindromic repeat-Cas9 (CRISPR/Cas9), derived from bacterial and archean immune systems, has received much attention from the scientific community as a powerful, targeted gene editing tool. The CRISPR/Cas9 system enables a simple, relatively effortless and highly specific gene targeting strategy through temporary or permanent genome regulation or editing. This endonuclease has enabled gene correction by taking advantage of the endogenous homology directed repair (HDR) pathway to successfully target and correct disease-causing gene mutations. Numerous studies using CRISPR support the promise of efficient and simple genome manipulation, and the technique has been validated in in vivo and in vitro experiments, indicating its potential for efficient gene correction at any genomic loci. In this chapter, we detailed various strategies related to gene editing using the CRISPR/Cas9 system. We also outlined strategies to improve the efficiency of gene correction via the HDR pathway and to improve viral and non-viral mediated gene delivery methods, with an emphasis on their therapeutic potential for correcting genetic disorder in humans and other mammals.