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Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex (ALS/PDC), a rare and complex neurological disorder, is predominantly observed in the Western Pacific islands, including regions of Japan, Guam, and Papua. This enigmatic condition continues to capture medical attention due to affected patients displaying symptoms that parallel those seen in either classical amyotrophic lateral sclerosis (ALS) or Parkinson's disease (PD). Distinctly, postmortem examinations of the brains of affected individuals have shown the presence of α-synuclein aggregates and TDP-43, which are hallmarks of PD and classical ALS, respectively. These observations are further complicated by the detection of phosphorylated tau, accentuating the multifaceted proteinopathic nature of ALS/PDC. The etiological foundations of this disease remain undetermined, and genetic investigations have yet to provide conclusive answers. However, emerging evidence has implicated the contribution of astrocytes, pivotal cells for maintaining brain health, to neurodegenerative onset, and likely to play a significant role in the pathogenesis of ALS/PDC. Leveraging advanced induced pluripotent stem cell technology, our team cultivated multiple astrocyte lines to further investigate the Japanese variant of ALS/PDC (Kii ALS/PDC). CHCHD2 emerged as a significantly dysregulated gene when disease astrocytes were compared to healthy controls. Our analyses also revealed imbalances in the activation of specific pathways: those associated with astrocytic cilium dysfunction, known to be involved in neurodegeneration, and those related to major neurological disorders, including classical ALS and PD. Further in-depth examinations revealed abnormalities in the mitochondrial morphology and metabolic processes of the affected astrocytes. A particularly striking observation was the reduced expression of CHCHD2 in the spinal cord, motor cortex, and oculomotor nuclei of patients with Kii ALS/PDC. In summary, our findings suggest a potential reduction in the support Kii ALS/PDC astrocytes provide to neurons, emphasizing the need to explore the role of CHCHD2 in maintaining mitochondrial health and its implications for the disease.
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Esclerosis Amiotrófica Lateral , Astrocitos , Proteínas de Unión al ADN , Proteínas Mitocondriales , Factores de Transcripción , Femenino , Humanos , Masculino , Esclerosis Amiotrófica Lateral/patología , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Astrocitos/patología , Astrocitos/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Mitocondrias/patología , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
BACKGROUND: The development of induced pluripotent stem cells (iPSCs) technology has enabled human cellular disease modeling for inaccessible cell types, such as neural cells in the brain. However, many of the iPSC-derived disease models established to date typically involve only a single cell type. These monoculture models are inadequate for accurately simulating the brain environment, where multiple cell types interact. The limited cell type diversity in monoculture models hinders the accurate recapitulation of disease phenotypes resulting from interactions between different cell types. Therefore, our goal was to create cell models that include multiple interacting cell types to better recapitulate disease phenotypes. METHODS: To establish a co-culture model of neurons and astrocytes, we individually induced neurons and astrocytes from the same iPSCs using our novel differentiation methods, and then co-cultured them. We evaluated the effects of co-culture on neurons and astrocytes using immunocytochemistry, immuno-electron microscopy, and Ca2+ imaging. We also developed a co-culture model using iPSCs from a patient with familial Alzheimer's disease (AD) patient (APP V717L mutation) to investigate whether this model would manifest disease phenotypes not seen in the monoculture models. RESULTS: The co-culture of the neurons and astrocytes increased the branching of astrocyte processes, the number of GFAP-positive cells, neuronal activities, the number of synapses, and the density of presynaptic vesicles. In addition, immuno-electron microscopy confirmed the formation of a tripartite synaptic structure in the co-culture model, and inhibition of glutamate transporters increased neuronal activity. Compared to the co-culture model of the control iPSCs, the co-culture model of familial AD developed astrogliosis-like phenotype, which was not observed in the monoculture model of astrocytes. CONCLUSIONS: Co-culture of iPSC-derived neurons and astrocytes enhanced the morphological changes mimicking the in vivo condition of both cell types. The formation of the functional tripartite synaptic structures in the co-culture model suggested the mutual interaction between the cells. Furthermore, the co-culture model with the APP V717L mutation expressed in neurons exhibited an astrocytic phenotype reminiscent of AD brain pathology. These results suggest that our co-culture model is a valuable tool for disease modeling of neurodegenerative diseases.
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Introduction: 17ß-Estradiol (E2) is a sex hormone that has been previously demonstrated to have neurotherapeutic effects on animal models of Alzheimer's disease (AD). However, clinical trials on E2 replacement therapy for preventing AD onset yielded inconsistent results. Therefore, it is imperative to clarify the therapeutic effects of E2 on human cells. In this study, we utilized induced pluripotent stem cells (iPSCs) derived from multiple AD donors to explore the therapeutic effects of E2 on the in vitro model of human cells. Methods: We conducted a systematic review and meta-analysis using a random-effects model of the previously reported AD clinical trials to summarize the effects of E2 replacement therapy on AD prevention. Subsequently, we induced iPSCs from the donors of the healthy control (1210B2 line (female) and 201B7 line (female)), the familial AD (APP V717L line (female) and APP KM670/671NL line (female)), and the sporadic AD (UCSD-SAD3.7 line (APOE ε3/ε3) (male), UCSD-SAD7D line (APOE ε3/ε4) (male), and TMGH-1 line (APOE ε3/ε3) (female)), then differentiated to neurons. In addition to the mono-culture model of the neurons, we also examined the effects of E2 on the co-culture model of neurons and astrocytes. Results: The meta-analysis of the clinical trials concluded that E2 replacement therapy reduced the risk of AD onset (OR, 0.69; 95 % confidence interval [CI], 0.53-0.91; I2 = 82 %). Neural models from the iPSCs of AD donors showed an increase in secreted amyloid-beta (Aß) levels in the mono-culture model and an astrogliosis-like phenotype in the co-culture model. E2 treatment to the neuronal models derived from the iPSCs enhanced neuronal activity and increased neurite complexity. Furthermore, E2 treatment of the co-culture model ameliorated the astrogliosis-like phenotype. However, in contrast to the previous reports using mouse models, E2 treatment did not change AD pathogenesis, including Aß secretion and phosphorylated tau (pTau) accumulation. Conclusion: E2 treatment of the human cellular model did not impact Aß secretion and pTau accumulation, but promoted neuronal plasticity and alleviated the astrogliosis-like phenotype. The limited effects of E2 may give a clue for the mixed results of E2 clinical trials.
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Human neural cell models derived from induced pluripotent stem cells (iPSCs) have been widely accepted to model various neurodegenerative diseases such as Alzheimer's disease (AD) in vitro. Although the most common sources of iPSCs are fibroblasts and peripheral blood mononuclear cells, the collection of these cells is invasive. To reduce the donor's burden, we propose the use of urine-derived cells (UDCs), which can be obtained non-invasively from a urine sample. However, the collection of UDCs from elderly donors suffering from age-related diseases such as AD has not been reported, and it is unknown whether these UDCs from the donor aged over 80 years old can be converted into iPSCs and differentiated into neural cells. In this study, we reported a case of using the UDCs from the urine sample of an 89-year-old AD patient, and the UDCs were successfully reprogrammed into iPSCs and differentiated into neural cells in four different ways: (i) the dual SMAD inhibition with small-molecules via the neural progenitor precursor stage, (ii) the rapid induction method using transient expression of Ngn2 and microRNAs without going through the neural progenitor stage, (iii) the cortical brain organoids for 3D culture, and (iv) the human astrocytes. The accumulation of phosphorylated Tau proteins, which is a pathological hallmark of AD, was examined in the neuronal models generated from the UDCs of the aged donor. The application of this cell source will broaden the target population for disease modeling using iPS technology.
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In Japan, a considerable number of foreigners encounter challenges in accessing appropriate healthcare services due to the lack of insurance coverage. However, the absence of a public database on these individuals makes it difficult to assess their health problems and healthcare access status. This study aims to investigate the characteristics of vulnerable Thai patients in Japan and to shed light on the specific challenges they face within Japan's healthcare system. A retrospective analysis was conducted using records of patients who required emergency healthcare support from the Royal Thai Embassy in Tokyo between 2004 and 2020. Descriptive statistical analyses were performed to examine the general characteristics, insurance status, and diseases of the patients. Additionally, patients were classified as either prolonged residents or brief residents based on their duration of stay in Japan until hospital admission (1 year or more or less than 1 year). A total of 74 patients were identified, with the majority (91.9%) lacking insurance coverage. Notably, there was an increase in the number of brief residents, including tourists, during the 2010s. Prolonged residents were more likely to experience chronic diseases, whereas brief residents were more prone to sustaining injuries. The patient records from the Thai Embassy consistently highlight the urgent requirement for emergency healthcare support within this population. However, the existing policies in Japan fall short in adequately addressing the healthcare access needs of this vulnerable population. Therefore, it is crucial to provide additional support and interventions to enhance their healthcare access.
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Numerous undocumented and uninsured foreigners living in Japan have faced barriers when trying to obtain appropriate healthcare services, which have occasionally led to issues with unpaid medical bills to medical institutions. Although information on health and socioeconomic status is essential to tackle such issues, relevant data has been unavailable due to difficulties in contacting this population. This study involved a cross-sectional survey using questionnaires concerning the general demographic characteristics, socioeconomic status, health profiles, information access, and knowledge/attitude/practice of health insurance of Thai nationals living in Japan. The study participants included Thai nationals who lived in Tokyo and the surrounding prefectures. The survey was conducted mainly at public religious events from September 2022 to December 2022. Overall, the questionnaires were obtained from 84 participants, though 67 participants were included in the final analysis after excluding missing variables. There were participants with unspecified visa status (32.8%) and uninsured status (40.3%). Among them, 86.4% expressed positive attitudes towards health insurance. However, multivariate multivariable regression analyses revealed the low insurance practice status among the unspecified visa group (aOR, 0.02; 95% CI, 0.00-0.13). Overall, the results reveal limited access to healthcare services in subgroups of Thai immigrants in Japan.
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Emigrantes e Inmigrantes , Accesibilidad a los Servicios de Salud , Pueblos del Sudeste Asiático , Humanos , Estudios Transversales , TokioRESUMEN
Empagliflozin is a sodium-glucose cotransporter-2 inhibitor widely used in the treatment of diabetes mellitus and heart failure. Our case study involved a 68-year-old patient who was admitted to the hospital because of a cerebral infarction. The patient was simultaneously diagnosed with diabetes mellitus and heart failure, for which empagliflozin was initiated. However, food and fluid intake were reduced due to poor appetite. In addition to the side effects of empagliflozin, the patient developed severe dehydration and cardiac arrest. Careful assessment of dehydration and preventive water intake is recommended in elderly patients and those with neurological deficits, especially when receiving empagliflozin.
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Diabetes Mellitus Tipo 2 , Paro Cardíaco , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Anciano , Compuestos de Bencidrilo , Deshidratación/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucósidos , Paro Cardíaco/inducido químicamente , Paro Cardíaco/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Hipoglucemiantes/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversosRESUMEN
Sporadic Alzheimer's disease (sAD) is a neurodegenerative disease that has the highest prevalence among patients with dementia. The genetic risk factors for sAD are comprised of many single nucleotide polymorphisms (SNPs), as indicated by genome-wide association studies. Herein, we generated the KEIOi005-A-induced pluripotent stem cell (iPSC) line from urine-derived cells (UDCs) of a mild Alzheimer's disease (AD) patient with multiple sAD risk SNPs comprising T > C heterozygous APOE ε3/ε4 (rs429358), A > G heterozygous BIN1 (rs744373), and T > G homozygous MS4A6A (rs610932). The established iPSC line demonstrates normal stemness and pluripotency and can be used for in vitro disease modeling of AD.
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Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Polimorfismo de Nucleótido SimpleRESUMEN
Alzheimer's disease (AD) is an aging-dependent neurodegenerative disease that impairs cognitive function. Although the main pathologies of AD are the aggregation of amyloid-beta (Aß) and phosphorylated Tau protein, the mechanisms that lead to these pathologies and their effects are believed to be heterogeneous among patients. Many epidemiological studies have suggested that sex is involved in disease prevalence and progression. The reduction of sex hormones contributes to the pathogenesis of AD, especially in females, suggesting that the supplementation of sex hormones could be a therapeutic intervention for AD. However, interventional studies have revealed that hormone therapy is beneficial under limited conditions in certain populations with specific administration methods. Thus, this suggests the importance of identifying crucial factors that determine hormonal effects in patients with AD. Based on these factors, it is necessary to decide which patients will receive the intervention before starting it. However, the long observational period and many uncontrollable environmental factors in clinical trials made it difficult to identify such factors, except for the APOE ε4 allele. Induced pluripotent stem cells (iPSCs) derived from patients can differentiate into neurons and recapitulate some aspects of AD pathogenesis. This in vitro model allows us to control non-cell autonomous factors, including the amount of Aß aggregates and sex hormones. Hence, iPSCs provide opportunities to investigate sex-dependent pathogenesis and predict a suitable population for clinical trials of hormone treatment.
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Sole measurement of plasma vitamin B12 is no longer enough to identify vitamin B12 (B12) deficiency. When plasma vitamin B12 is in the low-normal range, especially between 201 and 350 ng/L, B12 deficiency should be assessed by measurements of plasma homocysteine and/or plasma methylmalonic acid (MMA). However, these biomarkers also accumulate during renal impairment, leading to a decreased specificity for B12 deficiency. In such cases, urinary methylmalonic acid/creatinine ratio (uMMA/C) could be of interest, due to the stable urinary excretion of MMA. The objectives were to evaluate the influence of renal impairment on uMMA/C compared to plasma homocysteine and plasma methylmalonic acid, and to determine the diagnostic performances of uMMA/C in the diagnosis of B12 deficiency. We prospectively studied 127 patients with a plasma B12 between 201 and 350 ng/L. We noticed that uMMA/C was not dependent on renal function (p = 0.34), contrary to plasma homocysteine and plasma methylmalonic acid. uMMA/C showed a perspective diagnostic performance (AUC 0.71 [95% CI: 0.62-0.80]) and the threshold of 1.45 umol/mmol presented a high degree of specificity (87.9% [95% CI: 72.0-98.9]). In conclusion, uMMA/C is a promising biomarker to assess vitamin B12 status in doubtful cases, notably during renal impairment.
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Pericytes are mesenchymal cells that surround the endothelial cells of small vessels in various organs. These cells express several markers, such as NG2, CD146, and PDGFRß, and play an important role in the stabilization and maturation of blood vessels. It was also recently revealed that like mesenchymal stem cells (MSCs), pericytes possess multilineage differentiation capacity, especially myogenic, adipogenic, and fibrogenic differentiation capacities. Although some previous studies have reported that pericytes also have osteogenic potential, the osteogenesis of pericytes can still be further elucidated. In the present study, we established novel methods for isolating and culturing primary murine pericytes. An immortalized pericyte line was also established. Multilineage induction of the pericyte line induced osteogenesis, adipogenesis, and chondrogenesis of the cells in vitro. In addition, pericytes that were injected into the fracture site of a bone fracture mouse model contributed to callus formation. Furthermore, in vivo pericyte-lineage-tracing studies demonstrated that endogenous pericytes also differentiate into osteoblasts and osteocytes and contribute to bone fracture healing as a cellular source of osteogenic cells. Pericytes can be a promising therapeutic candidate for treating bone fractures with a delayed union or nonunion as well as bone diseases causing bone defects.