Cohen syndrome is an autosomal recessive disorder caused by VPS13B (COH1) gene mutations. This syndrome is significantly underdiagnosed and is characterized by intellectual disability, microcephaly, autistic symptoms, hypotension, myopia, retinal dystrophy, neutropenia, and obesity. VPS13B regulates intracellular membrane transport and supports the Golgi apparatus structure, which is critical for neuron formation. We generated induced pluripotent stem cells from two patients with pronounced manifestations of Cohen syndrome and differentiated them into neural stem cells and neurons. Using transmission electron microscopy, we documented multiple new ultrastructural changes associated with Cohen syndrome in the neuronal cells. We discovered considerable disturbances in the structure of some organelles: Golgi apparatus fragmentation and swelling, endoplasmic reticulum structural reorganization, mitochondrial defects, and the accumulation of large autophagosomes with undigested contents. These abnormalities underline the ultrastructural similarity of Cohen syndrome to many neurodegenerative diseases. The cell models that we developed based on patient-specific induced pluripotent stem cells can serve to uncover not only neurodegenerative processes, but the causes of intellectual disability in general.

The human induced pluripotent stem cell (iPSC) lines, iCS-MAF1-1 and iCS-MAF1-11, were generated from fibroblasts. The donor has a heterozygous mutation in the VPS13B gene, which manifests in her child as Cohen syndrome. It is a Golgi pathology, characterized by postnatal microcephaly and delayed growth and mental development. However, the process underlying pathological changes leading to the onset of the disease is still unknown. The use of iPSC will allow describing the early stages of neurogenesis, which is undoubtedly relevant for identifying key stages of development, at which phenotypic manifestations of mutations in the VPS13B gene are found.

The Notch signaling pathway is a critical regulator of embryonic brain development. Among its four mammalian receptors, Notch1 and Notch2 are particularly significant in the developing cortex, yet their roles in human neurodevelopment are not well understood. In murine cortex development, Notch1 primarily regulates early progenitor identity and neurogenesis, while Notch2 is required for maintaining radial glial cells at later stages. However, it is unclear whether these functions are conserved in the human developing brain. In this study, we used cerebral organoids as an in vitro model of early human corticogenesis and conducted lentiviral shRNA-mediated knockdowns of NOTCH1 and NOTCH2. Our findings indicate that NOTCH1 is essential for organoid growth, lumen morphogenesis, radial glial identity, and progenitor proliferation. In contrast, depleting NOTCH2 did not significantly affect these early developmental processes. These results demonstrate that NOTCH1 and NOTCH2 have potentially non-redundant and temporally distinct roles in early human corticogenesis, reflecting receptor-specific specialization within the Notch signaling pathway.

BACKGROUND : Deintensification of basal-bolus insulin therapy (BBIT) with simplification of the treatment regimen is a possible and necessary therapeutic strategy for some patients with type 2 diabetes (T2D). One of the options for deintensification is the transition to fixed combination of insulin glargine/lixisenatide (iGlarLixi). AIM : To determine the efficacy and safety of deintensification of BBIT in hospitalized patients with T2D by switching to iGlarLixi under continuous glucose monitoring (CGM). MATERIALS AND METHODS: Design: single-center, comparative, observational study in real-world settings. A total of 283 T2D patients on BBIT were included, 118 subjects underwent BBIT deintensification under CGM control according to clinical indications, 165 patients continued BBIT. Thirty patients were re-examined one year after deintensification. Time In target Range (TIR), Time Above Range (TAR), Time Below Range (TBR), as well as Coefficient of Variation (CV), Mean Amplitude of Glycemic Excursions (MAGE), Lability Index (LI), and Mean Absolute Glucose rate of change (MAG) were estimated. Endogenous insulin secretion was assessed by fasting and 2-hour postprandial C-peptide levels. The estimated glucose disposal rate (eGDR) was used as a measure of insulin sensitivity. RESULTS : The groups were similar in age, diabetes duration, glycated hemoglobin (HbA1c) and eGDR. Body mass index (BMI) and C-peptide levels were higher, while the duration of insulin therapy and initial daily insulin dose (DID) were lower in patients of the deintensification group (all p<0.0004). During deintensification, DID was reduced (from 64 to 30 U/day, p13.9 mmol/L), CV, MAGE and MAG were lower (all p<0.05). In multivariate regression analysis, BMI, DID and fasting C-peptide were associated with successful deintensification. In ROC analysis, fasting C-peptide was the best predictor with a cut-off point of 0.92 ng/mL. One year after the treatment deintensification, there was a decrease in HbA1c (-0.5%, p=0.001) and body weight (-0.8 kg, p=0.003) and an increase in postprandial C-peptide levels (p=0.029) without changes in eGDR. CONCLUSION : Switching to iGlarLixie is an effective therapeutic option for patients with T2D with normal C-peptide levels who require deintensification of BBIT.

Introduction: Human cerebral organoids (COs) are sophisticated three-dimensional (3D) models that successfully replicate the 3D cytoarchitecture of human brain development in its early stages. Co-cultivation of COs obtained from human-induced pluripotent stem cells with 3D U-87 MG glioblastoma cell spheroids (glioblastoma–CO assembloid [GCOA]) represents a robust strategy for modeling brain cancer behavior. Objectives: This study aims to evaluate the feasibility of using GCOAs and 3D U-87 MG glioblastoma cell spheroids as in vitro cell models to evaluate the cytotoxic effect of the oncolytic recombinant vaccinia virus-granulocyte–macrophage colony-stimulating factor (VV-GM-CSF)-Lact compared to the VV-GMCSF-del virus. Methods: To assess the cytotoxicity of two virus strains, we used fluorescent and confocal microscopy, spectrophotometry, the MTT assay, and real-time polymerase chain reaction Results: Glioblastoma cells died faster in the presence of VV-GMCSF-Lact virus, and 3D spheroids infected with this virus contained more caspase-3-positive cells. On the 10th day in GCOA, glioblastoma cells began to invade the interior of the CO. Under conditions of 3D spheroid and GCOA infection with recombinant viruses, three differentially expressed genes – FSCN1, SCUBE2, and TNFRSF9 – associated with invasion were analyzed. Conclusion: These 3D models of glioblastoma can be used in the development of antitumor drugs to study their cytotoxic effects.

Insulin is used in the treatment of a significant proportion of patients with type 2 diabetes (T2D), while many patients do not achieve glycemic control targets. Aim of the study was to assess the achievability of target parameters of time in ranges and glucose variability (GV) in hospitalized patients with T2D during insulin therapy adjustment under the control of continuous glucose monitoring (CGM) and to determine factors influencing these parameters. Material and methods . A retrospective comparative single-center study was conducted in real world settings. Patients were divided into 3 groups: 1) basal insulin (BI) therapy; 2) pre-mixed insulin (PMI) therapy; 3) basal-bolus insulin therapy (BBIT) in the mode of multiple daily injections. Time in the target range (TIR), time in the range above and below the target (TAR L-1, TAR L-2, TBR-L1, TBR L-2), coefficient of variability (CV), mean amplitude of glucose excursions (MAGE), lability index (LI), and mean absolute glucose rate of change (MAG) were derived from CGM recordings. Results . The study recruited 371 patients (167 were on BI, 40 on PMI, and 164 on BBIT). The mean glucose level, TIR, TBR, and TAR L-1 did not differ between three groups. TAR L-2 values and GV indices (CV, MAGE, LI) were higher in patients on BBIT than in those on BI. Patients on PMI did not show significant differences from other groups. In multivariate regression analysis, C-peptide level turned out to be an independent predictor of CV, MAGE, and LI; body mass index was associated with MAG and LI. Conclusions. Correction of insulin therapy under the CGM control allows achieving target glucose values in most patients with T2D. Patients on BBIT have higher GV than those on BI at similar TIR. The GV parameters in patients with T2D on insulin therapy are inversely associated with endogenous insulin secretion (C-peptide level).