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Glioblastoma is a highly aggressive brain tumour that creates an immunosuppressive microenvironment. Microglia, the brain's resident immune cells, play a crucial role in this environment. Glioblastoma cells can reprogramme microglia to create a supportive niche that promotes tumour growth. However, the mechanisms controlling the acquisition of a transcriptome associated with a tumour-supportive microglial reactive state are not fully understood. In this study, we investigated changes in the transcriptional profile of BV2 microglia exposed to C6 glioma cells. RNA-sequencing analysis revealed a significant upregulation of microglial inhibitor of DNA binding 1 (Id1) and Id2, helix-loop-helix negative transcription regulatory factors. The concomitant regulation of microglial ETS proto-oncogene 2, transcription factor (ETS2)-target genes, i.e., Dusp6, Fli1, Jun, Hmox1, and Stab1, led us to hypothesize that ETS2 could be regulated by ID proteins. In fact, ID2-ETS2 protein interactions increased in microglia exposed to glioma cells. In addition, perturbation of the ID2-ETS2 transcriptional axis influenced the acquisition of a microglial tumour-supportive phenotype. ID2 and ETS2 genes were found to be expressed by the tumour-associated microglia isolated from human glioblastoma tumour biopsies. Furthermore, ID2 and ETS2 gene expressions exhibited inverse prognostic values in patients with glioma in cohorts from The Cancer Genome Atlas. Collectively, our findings indicate that the regulation of ETS2 by ID2 plays a role in the transcriptional regulation of microglia in response to stimuli originating from glioblastoma cells, information that could lead to developing therapeutic strategies to manipulate microglial tumour-trophic functions., (© 2024. The Author(s).)

Alzheimer's disease is a progressive neurological disorder causing memory loss and cognitive decline. The underlying causes of cognitive deterioration and neurodegeneration remain unclear, leading to a lack of effective strategies to prevent dementia. Recent evidence highlights the role of neuroinflammation, particularly involving microglia, in Alzheimer's disease onset and progression. Characterizing the initial phase of Alzheimer's disease can lead to the discovery of new biomarkers and therapeutic targets, facilitating timely interventions for effective treatments. We used the App NL-G-F knock-in mouse model, which resembles the amyloid pathology and neuroinflammatory characteristics of Alzheimer's disease, to investigate the transition from a pre-plaque to an early plaque stage with a combined functional and molecular approach. Our experiments show a progressive decrease in the power of cognition-relevant hippocampal gamma oscillations during the early stage of amyloid pathology, together with a modification of fast-spiking interneuron intrinsic properties and postsynaptic input. Consistently, transcriptomic analyses revealed that these effects are accompanied by changes in synaptic function-associated pathways. Concurrently, homeostasis- and inflammatory-related microglia signature genes were downregulated. Moreover, we found a decrease in Iba1-positive microglia in the hippocampus that correlates with plaque aggregation and neuronal dysfunction. Collectively, these findings support the hypothesis that microglia play a protective role during the early stages of amyloid pathology by preventing plaque aggregation, supporting neuronal homeostasis, and overall preserving the oscillatory network's functionality. These results suggest that the early alteration of microglia dynamics could be a pivotal event in the progression of Alzheimer's disease, potentially triggering plaque deposition, impairment of fast-spiking interneurons, and the breakdown of the oscillatory circuitry in the hippocampus., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Molecular diversity of microglia, the resident immune cells in the CNS, is reported. Whether microglial subsets characterized by the expression of specific proteins constitute subtypes with distinct functions has not been fully elucidated. Here we describe a microglial subtype expressing the enzyme arginase-1 (ARG1; that is, ARG1 + microglia) that is found predominantly in the basal forebrain and ventral striatum during early postnatal mouse development. ARG1 + microglia are enriched in phagocytic inclusions and exhibit a distinct molecular signature, including upregulation of genes such as Apoe, Clec7a, Igf1, Lgals3 and Mgl2, compared to ARG1 - microglia. Microglial-specific knockdown of Arg1 results in deficient cholinergic innervation and impaired dendritic spine maturation in the hippocampus where cholinergic neurons project, which in turn results in impaired long-term potentiation and cognitive behavioral deficiencies in female mice. Our results expand on microglia diversity and provide insights into microglia subtype-specific functions., (© 2023. The Author(s).)

Caspases are a family of proteins mostly known for their role in the activation of the apoptotic pathway leading to cell death. In the last decade, caspases have been found to fulfill other tasks regulating the cell phenotype independently to cell death. Microglia are the immune cells of the brain responsible for the maintenance of physiological brain functions but can also be involved in disease progression when overactivated. We have previously described non-apoptotic roles of caspase-3 (CASP3) in the regulation of the inflammatory phenotype of microglial cells or pro-tumoral activation in the context of brain tumors. CASP3 can regulate protein functions by cleavage of their target and therefore could have multiple substrates. So far, identification of CASP3 substrates has been performed mostly in apoptotic conditions where CASP3 activity is highly upregulated and these approaches do not have the capacity to uncover CASP3 substrates at the physiological level. In our study, we aim at discovering novel substrates of CASP3 involved in the normal regulation of the cell. We used an unconventional approach by chemically reducing the basal level CASP3-like activity (by DEVD-fmk treatment) coupled to a Mass Spectrometry screen (PISA) to identify proteins with different soluble amounts, and consequently, non-cleaved proteins in microglia cells. PISA assay identified several proteins with significant change in their solubility after DEVD-fmk treatment, including a few already known CASP3 substrates which validated our approach. Among them, we focused on the Collectin-12 (COLEC12 or CL-P1) transmembrane receptor and uncovered a potential role for CASP3 cleavage of COLEC12 in the regulation of the phagocytic capacity of microglial cells. Taken together, these findings suggest a new way to uncover non-apoptotic substrates of CASP3 important for the modulation of microglia cell physiology., (© 2023. The Author(s).)

Long non-coding RNAs (lncRNAs) have been found to be involved in many biological processes, including the regulation of cell differentiation, but a complete characterization of lncRNA is still lacking. Additionally, there is evidence that lncRNAs interact with ribosomes, raising questions about their functions in cells. Here, we used a developmentally staged protocol to induce cardiogenic commitment of hESCs and then investigated the differential association of lncRNAs with polysomes. Our results identified lncRNAs in both the ribosome-free and polysome-bound fractions during cardiogenesis and showed a very well-defined temporal lncRNA association with polysomes. Clustering of lncRNAs was performed according to the gene expression patterns during the five timepoints analyzed. In addition, differential lncRNA recruitment to polysomes was observed when comparing the differentially expressed lncRNAs in the ribosome-free and polysome-bound fractions or when calculating the polysome-bound vs ribosome-free ratio. The association of lncRNAs with polysomes could represent an additional cytoplasmic role of lncRNAs, e.g., in translational regulation of mRNA expression.

Background and Aims: Cellular and animal models investigating extremely low frequency magnetic fields (ELF-MF) have reported promotion of leukocyte-endothelial interactions, angiogenesis, myofibroblast and keratinocyte proliferation, improvement of peripheral neuropathy and diabetic wound healing. In humans, it has also been reported that systemic exposure to ELF-MF stimulates peripheral blood mononuclear cells, promoting angiogenesis and healing of chronic leg ulcers. The aim of the study was to investigate the effect of exposing different blood volumes to specific ELF-MFs (120 Hz sinusoidal waves of 0.4-0.9 mT RMS) to induce healing of diabetic foot ulcers (DFUs)., Methods: Twenty six diabetic patients with non-responsive DFUs were divided into two exposure groups to receive treatment and record healing time. The forearm group, exposed to ELF-MF 2 h/day, twice weekly (3.6 l of blood/session); and the thorax group, exposed 25 min/day, 2 times/week (162.5 l of blood/session). Treatment period was 100 days or upon complete healing. Ulcer recurrences and adverse effects were investigated during short-term (<1 year) and long-term (3.4-7.8 years) follow-up., Results: Mean healing time was 61.48 ± 33.08 days in the forearm group and 62.56 ± 29.33 days for the thorax group. No adverse effects or ulcer recurrences in the original ulcer site were reported during treatment, the short-term follow-up period or the long-term follow-up period in both groups., Conclusions: Healing time was independent of the amount of blood exposed to ELF-MF used in this trial. ELF-MFs are effective and safe and could be applied to non-healing DFUs in conjunction with other preventive interventions to reduce DFUs complications., (Copyright © 2015 IMSS. Published by Elsevier Inc. All rights reserved.)

The inferior colliculus (IC) is a mesencephalic auditory nucleus involved in several functions including the analysis of the frequency and intensity of sounds as well as sound localization. In addition to auditory processes, the IC controls the expression of defensive responses. The objective of the present study was to test the hypothesis that the IC contributes to the maintenance of wakefulness. For this purpose, several experimental approaches were performed in urethane-anesthetized guinea pigs. Electrical or chemical stimulation of the IC resulted in electroencephalographic (EEG) desynchronization, theta rhythm in the hippocampus and an increase in heart rate; all of these effects suggest an arousal reaction. Furthermore, by means of extracellular unit recordings, we determined that most IC neurons increased their spontaneous and tone-evoked responses in association with EEG desynchronization. We also studied the effect on sleep and wakefulness of bilateral acute inhibition of the IC by microinjections of muscimol (a GABAA agonist), as well as the effect of bilateral IC lesions in chronically-instrumented (drug-free) guinea pigs. Acute (via muscimol microinjections), but not chronic (via electrolytic lesions) inhibition of the IC decreased wakefulness., We conclude that the IC plays an active role in the maintenance of wakefulness. Further, we propose that this nucleus may mediate arousal responses induced by biologically significant sounds., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Objective: To estimate the annual cost of treating patients with cirrhosis at the Mexican Institute of Social Security (IMSS per its abbreviation in Spanish)., Material and Methods: The annual cost of treating three stages of cirrhosis (Child-Pugh A, Child-Pugh B and Child-Pugh C) was estimated using micro-costing techniques and medical experts. These results were compared and contrasted with prices reported by IMSS., Results: The annual cost of treatment, in USA dollars, by Child-Pugh stage was: a) micro-costing results: $1110.17 stage A, $549.55 stage B and $348.16 stage C; b) opinion of medical experts: $1 633.64, $6564.04 and $19660.35, respectively; and c) IMSS costs: $4269.00, $16949.63 and $30249.25, respectively., Conclusions: The cost of treating patients with cirrhosis is considerable, and costs increase as the disease worsens. Cost estimates vary depending on the source of information, and the methodology used. There are discrepancies between the procedures reported in medical records and treatment recommendations by IMSS liver experts.

Seven higher plant species (Allium cepa, Arabidopsis thaliana, Glycine max, Hordeum vulgaris. Tradescantia paludosa, Vicia faba, and Zea mays) were reviewed for their ability to detect genotoxicity of chemical agents under the U.S. Environmental Protection Agency (U.S. EPA) Gene-Tox program in the late 1970s. Six bioassays-Allium and Vicia root tip chromosome breaks, Tradescantia chromosome break, Tradescantia micronucleus, Tradescantia-stamen-hair mutation, and Arabidopsis-mutation bioassays- were established from four plant systems that are currently in use for detecting the genotoxicity of environmental agents. Under the Gene-Tox program, the Crepis capillaris-chromosome-aberration test was added to the existing six bioassays. The current review is limited to chemical agents that exhibit a positive response to any of these seven plant bioassays. From 158 articles reviewed, 84 chemicals were compiled in three categories: carcinogens, clastogens, and mutagens. As none of these plant bioassays can detect tumor initiation or cancerous growth, the chemicals were categorized as carcinogens based on their characteristics defined by the U.S. EPA's Superfund Priority 1 List and/or by the chemical listings of the Sigma and Aldrich Chemical Companies. Certain mutagens were categorized in the same manner in addition to the agents detected as mutagens by these plant bioassays.

Iron is an essential nutrient for the survival and pathogenesis of bacteria, but relatively little is known regarding its transport and regulation in staphylococci. Based on the known sequences of ferric-uptake regulatory (fur) genes from several Gram-positive and Gram-negative bacteria, a fragment containing the fur homologue was cloned from a genomic library of Staphylococcus aureus RN450. Nucleotide sequence analysis of this fragment revealed the presence of a 447 bp ORF that encodes a putative 149 aa polypeptide with an apparent molecular mass of 17 kDa. A putative ferrichrome-uptake (fhu) operon, containing the conserved Fur-binding sequences (Fur box) in the promoter region, was also cloned from the same S. aureus library. To characterize the impact of Fur on the fhu operon, fur was cloned, overexpressed as a His-tagged protein and purified by Ni2+-affinity column chromatography. The recombinant protein was digested with enterokinase to remove the His tag. Electrophoretic mobility-shift assays indicated that Fur binds to the promoter region of the fhu operon in the presence of divalent cations. Fur also interacted with the promoter region of the recently reported sir operon that has been proposed to constitute a siderophore-transport system in S. aureus. The DNase I-protection assay revealed that Fur specifically binds to the Fur box located in the promoter region of the fhu operon. The primer-extension reaction indicated that the transcription-start site of the fhu operon was located inside the Fur box. S. aureus fur partially complemented a fur- mutation in Bacillus subtilis. The data suggest that Fur regulates iron-transport processes in S. aureus.