Neuroprotective Effects of AER-271 in a tMCAO Mouse Model: Modulation of Autophagy, Apoptosis, and Inflammation.

Following ischemic stroke, aquaporin 4 (AQP4) expression modifications have been associated with increased inflammation. However, the underlying mechanisms are not fully understood. This study aims to elucidate the mechanistic basis of post-cerebral ischemia-reperfusion (I/R) inflammation by employing the AQP4-specific inhibitor, AER-271. The middle cerebral artery occlusion (MCAO) model was used to induce ischemic stroke in mice. C57BL/6 mice were randomly allocated into four groups: sham operation, I/R, AER-271, and 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020) treatment, with observations recorded at 1 day, 3 days, and 7 days post-tMCAO. Each group consisted of 15 mice. Procedures included histological examination through HE staining, neurological scoring, Western blot analysis, and immunofluorescence staining. AER-271 treatment yielded significant improvements in post-stroke weight recovery and neurological scores, accompanied by a reduction in cerebral infarction volume. Moreover, AER-271 exhibited a noticeable influence on autophagic and apoptotic pathways, affecting the activation of both pro-inflammatory and anti-inflammatory cytokines. Alterations in the levels of inflammatory biomarkers MCP-1, NLRP3, and caspase 1 were also detected. Finally, a comparative assessment of the effects of AER-271 and TGN-020 in mitigating apoptosis and microglial polarization in ischemic mice revealed neuroprotective effects with no significant difference in efficacy. This study provides essential insights into the neuroprotective mechanisms of AER-271 in cerebral ischemia-reperfusion injury, offering potential clinical applications in the treatment of ischemic cerebrovascular disorders.

Autophagy Regulation Attenuates Neuroinflammation and Cognitive Decline in an Alzheimer's Disease Mouse Model with Chronic Cerebral Hypoperfusion.

This study investigates the role of autophagy regulation in modulating neuroinflammation and cognitive function in an Alzheimer's disease (AD) mouse model with chronic cerebral hypoperfusion (CCH). Using the APP23/PS1 mice plus CCH model, we examined the impact of autophagy regulation on cognitive function, neuroinflammation, and autophagic activity. Our results demonstrate significant cognitive impairments in AD mice, exacerbated by CCH, but mitigated by treatment with the autophagy inhibitor 3-methyladenine (3-MA). Dysregulation of autophagy-related proteins, accentuated by CCH, underscores the intricate relationship between cerebral blood flow and autophagy dysfunction in AD pathology. While 3-MA restored autophagic balance, rapamycin (RAPA) treatment did not induce significant changes, suggesting alternative therapeutic approaches are necessary. Dysregulated microglial polarization and neuroinflammation in AD+CCH were linked to cognitive decline, with 3-MA attenuating neuroinflammation. Furthermore, alterations in M2 microglial polarization and the levels of inflammatory markers NLRP3 and MCP1 were observed, with 3-MA treatment exhibiting potential anti-inflammatory effects. Our findings shed light on the crosstalk between autophagy and neuroinflammation in AD+CCH and suggest targeting autophagy as a promising strategy for mitigating neuroinflammation and cognitive decline in AD+CCH.

A machine-learning model that incorporates CD45 surface expression predicts hematopoietic progenitor cell recovery after freeze-thaw.

BACKGROUND AIMS: Sufficient doses of viable CD34+ (vCD34) hematopoietic progenitor cells (HPCs) are crucial for engraftment. Additional-day apheresis collections can compensate for potential loss during cryopreservation but incur high cost and additional risk. To aid predicting such losses for clinical decision support, we developed a machine-learning model using variables obtainable on the day of collection. METHODS: In total, 370 consecutive autologous HPCs, apheresis-collected since 2014 at the Children's Hospital of Philadelphia, were retrospectively reviewed. Flow cytometry was used to assess vCD34% on fresh products and thawed quality control vials. The ratio of vCD34% thawed to fresh, which we call "post-thaw index," was used as an outcome measure, with a "poor" post-thaw index defined as <70%. HPC CD45 normalized mean fluorescence intensity (MFI) was calculated by dividing CD45 MFI of HPCs to the CD45 MFI of lymphocytes in the same sample. We trained XGBoost, k-nearest neighbor and random forest models for the prediction and calibrated the best model to minimize falsely-reassuring predictions. RESULTS: In total, 63 of 370 (17%) products had a poor post-thaw index. The best model was XGBoost, with an area under the receiver operator curve of 0.83 evaluated on an independent test data set. The most important predictor for a poor post-thaw index was the HPC CD45 normalized MFI. Transplants after 2015, based on the lower of the two vCD34% values, showed faster engraftment than older transplants, which were based on fresh vCD34% only (average 10.6 vs 11.7 days, P = 0.0006). CONCLUSIONS: Transplants taking into account post-thaw vCD34% improved engraftment time in our patients; however, it came at the cost of unnecessary multi-day collections. The results from applying our predictive algorithm retrospectively to our data suggest that more than one-third of additional-day collections could have been avoided. Our investigation also identified CD45 nMFI as a novel marker for assessing HPC health post-thaw.

Correlation Analysis of Neutrophil/Albumin Ratio and Leukocyte Count/Albumin Ratio with Ischemic Stroke Severity.

Ischemic stroke (IS) is a common neurological disease in the elderly, but the relationship between neutrophil/albumin ratio (NAR) and leukocyte count/albumin ratio (LAR) and the severity of neurological function injury and early neurological deterioration (END) occurrence remain elusive in acute IS. A total of 299 patients with acute IS and 56 healthy controls were enrolled. According to the NIHSS score at admission, the disease group was divided into three groups (mild, moderate and severe IS), and the differences in five indexes NAR, LAR, neutrophil count, leukocyte count and albumin among the four groups were analyzed. Furthermore, explore the correlation between the above indicators and the severity of IS and END occurrence. The results showed that higher NAR, LAR, neutrophil count, leukocyte count levels and lower albumin levels were associated with acute IS, and the levels of NAR and LAR increased gradually in three groups of IS. NAR and LAR were positively and albumin was negatively correlated with the severity of IS. Meanwhile, NAR and LAR showed a good predictive value in identifying patients with END after acute IS. NAR and LAR may be predictors of the severity of IS and END occurrence after acute IS.

The local spiral structure of the Milky Way.

The nature of the spiral structure of the Milky Way has long been debated. Only in the last decade have astronomers been able to accurately measure distances to a substantial number of high-mass star-forming regions, the classic tracers of spiral structure in galaxies. We report distance measurements at radio wavelengths using the Very Long Baseline Array for eight regions of massive star formation near the Local spiral arm of the Milky Way. Combined with previous measurements, these observations reveal that the Local Arm is larger than previously thought, and both its pitch angle and star formation rate are comparable to those of the Galaxy's major spiral arms, such as Sagittarius and Perseus. Toward the constellation Cygnus, sources in the Local Arm extend for a great distance along our line of sight and roughly along the solar orbit. Because of this orientation, these sources cluster both on the sky and in velocity to form the complex and long enigmatic Cygnus X region. We also identify a spur that branches between the Local and Sagittarius spiral arms.

Manufacturing mesenchymal stromal cells for phase I clinical trials.

Mesenchymal stromal cells (MSCs) are multipotent progenitor cells capable of differentiating into adipocytes, osteoblasts and chondroblasts as well as secreting a vast array of soluble mediators. This potentially makes MSCs important mediators of a variety of therapeutic applications. They are actively under evaluation for immunomodulatory purposes such as graft-versus-host disease and Crohn's disease as well as regenerative applications such as stroke and congestive heart failure. We report our method of generating clinical-grade MSCs together with suggestions gathered from manufacturing experience in our Good Manufacturing Practices facility.

Mutation in the factor VII hepatocyte nuclear factor 4α-binding site contributes to factor VII deficiency.

Severe coagulant factor VII (FVII) deficiency in postpubertal dizygotic twin males results from two point mutations in the FVII gene, a promoter region T→C transition at -60 and a His-to-Arg substitution at amino acid 348; both mutations prevent persistence of plasma functional FVII. This report documents longitudinal laboratory measurements from infancy to adulthood of FVII coagulant activity (FVII:C) in the twin FVII-deficient patients; it also details specific biochemical analyses of the -60 T→C mutation. The results revealed FVII:C levels of less than 1% in infancy that remain severely decreased through puberty and into adulthood. In-vitro analyses utilizing hepatocyte nuclear factor 4α (HNF4α) co-transfection and a chromatin immunoprecipitation assay indicate that the -60 T→C mutation severely diminishes functional interaction between the FVII promoter and transcription factor HNF4α. The importance of interaction between the FVII gene and HNF4α in normal FVII expression provides an in-vivo illustration of the regulated expression of an autosomal gene encoding a coagulation protein. The constancy of FVII:C and peripubertal patient symptomatology reported here illustrates androgen-independent expression in contrast to expression with an analogous mutation in the promoter region of the gene encoding coagulation FIX.

Exchange of GATA factors mediates transitions in looped chromatin organization at a developmentally regulated gene locus.

Enhancers can regulate designate promoters over long distances by forming chromatin loops. Whether chromatin loops are lost or reconfigured during gene repression is largely unexplored. We examined the chromosome conformation of the Kit gene that is expressed during early erythropoiesis but is downregulated upon cell maturation. Kit expression is controlled by sequential occupancy of two GATA family transcription factors. In immature cells, a distal enhancer bound by GATA-2 is in physical proximity with the active Kit promoter. Upon cell maturation, GATA-1 displaces GATA-2 and triggers a loss of the enhancer/promoter interaction. Moreover, GATA-1 reciprocally increases the proximity in nuclear space among distinct downstream GATA elements. GATA-1-induced transitions in chromatin conformation are not simply the consequence of transcription inhibition and require the cofactor FOG-1. This work shows that a GATA factor exchange reconfigures higher-order chromatin organization, and suggests that de novo chromatin loop formation is employed by nuclear factors to specify repressive outcomes.

Mammalian ASH1L is a histone methyltransferase that occupies the transcribed region of active genes.

Histone lysine methylation regulates genomic functions, including gene transcription. Previous reports found various degrees of methylation at H3K4, H3K9, and H4K20 within the transcribed region of active mammalian genes. To identify the enzymes responsible for placing these modifications, we examined ASH1L, the mammalian homolog of the Drosophila melanogaster Trithorax group (TrxG) protein Ash1. Drosophila Ash1 has been reported to methylate H3K4, H3K9, and H4K20 at its target sites. Here we demonstrate that mammalian ASH1L associates with the transcribed region of all active genes examined, including Hox genes. The distribution of ASH1L in transcribed chromatin strongly resembles that of methylated H3K4 but not that of H3K9 or H4K20. Accordingly, the SET domain of ASH1L methylates H3K4 in vitro, and knockdown of ASH1L expression reduced H3K4 trimethylation at HoxA10 in vivo. Notably, prior methylation at H3K9 reduced ASH1L-mediated methylation at H3K4, suggesting cross-regulation among these marks. Drosophila ash1 and trithorax interact genetically, and the mammalian TrxG protein MLL1 and ASH1L display highly similar distributions and substrate specificities. However, by using MLL null cell lines we found that their recruitments occur independently of each other. Collectively, our data suggest that ASH1L occupies most, if not all, active genes and methylates histone H3 in a nonredundant fashion at a subset of genes.