Advances in the Differentiation of hiPSCs into Cerebellar Neuronal Cells.

The cerebellum has historically been primarily associated with the regulation of precise motor functions. However, recent findings suggest that it also plays a pivotal role in the development of advanced cognitive functions, including learning, memory, and emotion regulation. Pathological changes in the cerebellum, whether congenital hereditary or acquired degenerative, can result in a diverse spectrum of disorders, ranging from genetic spinocerebellar ataxias to psychiatric conditions such as autism, and schizophrenia. While studies in animal models have significantly contributed to our understanding of the genetic networks governing cerebellar development, it is important to note that the human cerebellum follows a protracted developmental timeline compared to the neocortex. Consequently, employing animal models to uncover human-specific molecular events in cerebellar development presents significant challenges. The emergence of human induced pluripotent stem cells (hiPSCs) has provided an invaluable tool for creating human-based culture systems, enabling the modeling and analysis of cerebellar physiology and pathology. hiPSCs and their differentiated progenies can be derived from patients with specific disorders or carrying distinct genetic variants. Importantly, they preserve the unique genetic signatures of the individuals from whom they originate, allowing for the elucidation of human-specific molecular and cellular processes involved in cerebellar development and related disorders. This review focuses on the technical advancements in the utilization of hiPSCs for the generation of both 2D cerebellar neuronal cells and 3D cerebellar organoids.

Research on factor analysis and method for evaluating grouting effects using machine learning.

The evaluation of grouting effects constitutes a critical aspect of grouting engineering. With the maturity of the grouting project, the workload and empirical characteristics of grouting effect evaluation are gradually revealed. In the context of the Qiuji coal mine's directional drilling and grouting to limestone aquifer reformation, this study thoroughly analyzes the influencing factors of grouting effects from geological and engineering perspectives, comparing these with various engineering indices associated with drilling and grouting. This led to the establishment of a "dual-process, multi-parameter, and multi-factor" system, employing correlation analysis to validate the selected indices' reasonableness and scientific merit. Utilizing the chosen indices, eight high-performing machine learning models and three parameter optimization algorithms were employed to develop a model for assessing the effectiveness of directional grouting in limestone aquifers. The model's efficacy was evaluated based on accuracy, recall, precision, and F-score metrics, followed by practical engineering validation. Results indicate that the "dual-process, multi-parameter, multi-factor" system elucidates the relationship between influencing factors and engineering parameters, demonstrating the intricacy of evaluating grouting effects. Analysis revealed that the correlation among the eight selected indicators-including the proportion of boreholes in the target rock strata, drilling length, leakage, water level, pressure of grouting, mass of slurry injected, permeability properties of limestone aquifers before being grouted, permeability properties of limestone aquifers after being grouted-is not substantial, underscoring their viability as independent indicators for grouting effect evaluation. Comparative analysis showed that the Adaboost machine learning model, optimized via a genetic algorithm, demonstrated superior performance and more accurate evaluation results. Engineering validation confirmed that this model provides a more precise and realistic assessment of grouting effects compared to traditional methods.

Methylene Blue Reduces Retinal Cell Inflammation, Apoptosis, and Oxidative Stress in a Rat Model of Diabetic Retinopathy via Sirtuin 1 Activation.

Objective: Diabetic retinopathy (DR), characterized by neuronal damage in the retina, is primarily driven by oxidative stress resulting from diabetes (DM). This study investigated the potential effects of methylene blue (MB) on streptozotocin (STZ)-induced DR. Methods: A rat model of DR was established via STZ injection, while a cell model was created using high-glucose (HG) exposure of human retinal microvascular endothelial cells. Evaluation of oxidative stress markers, pro-inflammatory cytokines, and pro-apoptotic proteins was performed based on their expression profiles in human retinal microvascular endothelial cells. Results: MB treatment significantly upregulated the expression of sirtuin 1 (SIRT1), which was found to be downregulated in the retinal tissues of STZ-treated rats and HG-exposed human retinal microvascular endothelial cells, as determined by polymerase chain reaction (PCR). Furthermore, MB therapy effectively suppressed STZ-induced oxidative stress, inflammation, and cell death. Consistent with the in vivo findings, MB activated the expression of SIRT1, thereby protecting HG-treated human retinal microvascular endothelial cells against oxidative stress, inflammation, and apoptosis. Conclusion: These results support the conclusion that MB mitigates DR by activating SIRT1, leading to a reduction of inflammation, apoptosis, and oxidative stress.

[Methylene blue reduces IL-1ß levels by enhancing ERK1/2 and AKT phosphorylation to improve diabetic retinopathy in rats].

Objective To investigate the neuroprotective effect of methylene blue on diabetic retinopathy in rats. Methods Thirty SD rats were randomly divided into blank, control and experimental groups. The control and experimental groups were induced with diabetes by streptozotocin (STZ) intraperitoneal injection. After 6 weeks of successful modeling, the experimental group received intravitreal injection of methylene blue at a dose of [0.2 mg/(kg.d)], while the control group received an equal amount of dimethyl sulfoxide (DMSO) intravitreal injection, both continuously injected for 7 days. ELISA was used to detect the levels of retinal superoxide dismutase (SOD), 8-iso-prostaglandin F2alpha (iPF2α) and interleukin-1ß (IL-1ß) in rats. Western blot analysis was used to detect the expression of retinal extracellular signal-regulated kinase 1/2 phosphorylation (p-ERK1/2) and phosphorylated protein kinase B (p-AKT), and PAS staining was used to detect retinal morphological changes. Results Compared with the blank group rats, the retinal SOD activity in the control and experimental group rats was significantly reduced. iPF2α, IL-1ß and p-ERK1/2 level increased, while p-AKT level decreased. Compared with the control group, the SOD activity of the experimental group rats increased. iPF2α and IL-1ß level went down, while p-ERK1/2 and p-AKT level went up significantly. The overall thickness of the retinal layer and the number of retinal ganglion cells were significantly reduced. Conclusion Methylene blue improves diabetic retinopathy in rats by reducing retinal oxidative stress and enhancing ERK1/2 and AKT phosphorylation.

Establishment of an induced pluripotent stem cell (iPSC) line (INNDSUi001-A) from a healthy female Chinese Han.

We have established the human induced pluripotent stem cell (hiPSC) line (INNDSUi001-A) from skin fibroblasts of a healthy 24-year-old female individual by using non-integrating reprogramming method. The resulted cells had typical features of embryonic stem cell as indicated by expression of specific pluripotency markers and had the capability of in vitro differentiation into the three germ layers. This iPSC line can be used as a healthy control for disease study.

Generation of a human induced pluripotent stem cell line (INNDSUi003-A) derived from patient with Becker muscular dystrophy (BMD).

Becker muscular dystrophy (BMD), an X-linked recessive disorder caused of mutation in the dystrophin gene, is characterized by progressive muscle degeneration and proximal muscle weakness. We generated a human induced pluripotent stem cell (hiPSC) line from the fibroblasts isolated from patient with BMD by non-integrating reprogramming methods. The iPSC line highly expresses pluripotency markers, displays the normal karyotype and is able to differentiate into the three germ layers in vitro. The iPSC line will be a useful tool to study the pathogenesis of BMD and for drug screening.

The impact of cardiomotor rehabilitation on endothelial function in elderly patients with chronic heart failure.

BACKGROUND: To explore the effects of cardiac exercise rehabilitation on peripheral blood endothelial progenitor cells (EPC) in elderly patients with chronic heart failure. METHODS: 80 elderly patients with chronic heart failure were selected from March 2017 to March 2019 and randomly divided into two groups (N = 40). The control group was treated routinely and walked freely for 30-60 min every day. The patients in the exercise rehabilitation group developed a cardiac exercise rehabilitation plan. Then, cardiac function and peripheral blood B-natriuretic peptide (BNP) levels in the two groups were compared. The cell viability, proliferation, apoptosis, and invasion ability of EPCs were detected. The levels of the PI3K/AKT pathway and eNOS and VEGF were compared. RESULTS: There were no significant differences in all indexes between the two groups before treatment (P > 0.05), and both improved significantly after treatment (P < 0.05). After treatment, LVEF and LVFS in the exercise rehabilitation group were significantly higher than those in the control group (P < 0.05), and LVEDD and LVESD were significantly lower than those in the control group (P < 0.05). The BNP level in the exercise rehabilitation group was significantly lower than that in the control group (P < 0.05). The cell viability, proliferation, invasion ability of EPC, and the levels of PI3K, AKT, eNOS, and VEGF mRNA and protein in the exercise rehabilitation group were significantly higher than those in the control group. Apoptosis rate was significantly lower than those in the control group (P < 0.05). CONCLUSIONS: Visceral exercise rehabilitation can improve cardiac ejection and myocardial function in elderly patients with chronic heart failure, and can promote the vitality, proliferation, and invasion of peripheral blood EPC, and promote the expression of eNOS and VEGF by upregulating the PI3K/AKT pathway to promote angiogenesis and endothelial function.

Growth Differentiation Factor 15 Is a Novel Diagnostic Biomarker of Mitochondrial Diseases.

The present study aimed to investigate whether serum growth differentiation factor 15 concentration is a valuable and reliable diagnostic biomarker of mitochondrial diseases. We examined consecutive patients with mitochondrial diseases, in comparison with patients with non-mitochondrial disease neuromuscular disorders and healthy controls. The serum concentrations of growth differentiation factor 15 were measured by ELISA, and compared with those of FGF21, lactate, and creatine kinase. We also evaluated the correlations between growth differentiation factor 15 concentrations and the Newcastle Mitochondrial Disease Adult Scale, numbers of ragged-red fibers, and COX-negative fibers in the biopsied muscles. The median serum growth differentiation factor 15 concentration was significantly elevated in 42 patients with mitochondrial diseases, compared with 20 patients with non-mitochondrial disease neuromuscular disorders and 50 healthy controls. The area under the curve of growth differentiation factor 15 for the diagnosis of muscle-manifesting mitochondrial diseases was 0.999, in comparison with those area under the curves of the other biomarkers including fibroblast growth factor 21 (0.935, p < 0.01), lactate (0.845 for p < 0.001), and creatine kinase (0.575, p < 0.001). Growth differentiation factor 15 was significantly correlated with mitochondrial disease severity and the proportion of ragged-red fibers identified in the biopsied muscles. Circulating growth differentiation factor 15 measurement is a superior biomarker with high sensitivity and specificity, which can be used as a non-invasive test to screen for primary mitochondrial diseases and dysmetabolic myopathy with associated mitochondrial dysfunction in susceptible individuals.

Skeletal muscle increases FGF21 expression in mitochondrial disorders to compensate for energy metabolic insufficiency by activating the mTOR-YY1-PGC1α pathway.

Fibroblast growth factor 21 (FGF21) is a growth factor with pleiotropic effects on regulating lipid and glucose metabolism. Its expression is increased in skeletal muscle of mice and humans with mitochondrial disorders. However, the effects of FGF21 on skeletal muscle in response to mitochondrial respiratory chain deficiency are largely unknown. Here we demonstrate that the increased expression of FGF21 is a compensatory response to respiratory chain deficiency. The mRNA and protein levels of FGF21 were robustly raised in skeletal muscle from patients with mitochondrial myopathy or MELAS. The mammalian target of rapamycin (mTOR) phosphorylation levels and its downstream targets, Yin Yang 1 (YY1) and peroxisome proliferator-activated receptor γ, coactivator 1α (PGC-1α), were increased by FGF21 treatment in C2C12 myoblasts. Activation of the mTOR-YY1-PGC1α pathway by FGF21 in myoblasts regulated energy homeostasis as demonstrated by significant increases in intracellular ATP synthesis, oxygen consumption rate, activity of citrate synthase, glycolysis, mitochondrial DNA copy number, and induction of the expression of key energy metabolic genes. The effects of FGF21 on mitochondrial function required phosphoinositide 3-kinase (PI3K), which activates mTOR. Inhibition of PI3K, mTOR, YY1, and PGC-1α activities attenuated the stimulating effects of FGF21 on intracellular ATP levels and mitochondrial gene expression. Our findings revealed that mitochondrial respiratory chain deficiency elicited a compensatory response in skeletal muscle by increasing the FGF21 expression levels in muscle, which resulted in enhanced mitochondrial function through an mTOR-YY1-PGC1α-dependent pathway in skeletal muscle.