Glioblastoma (GBM) is an aggressive brain cancer associated with poor overall survival. The metabolic status and tumor microenvironment of GBM cells have been targeted to improve therapeutic strategies. TLR4 is an important innate immune receptor capable of recognizing pathogens and danger-associated molecules. We have previously demonstrated the presence of TLR4 in GBM tumors and the decreased viability of the GBM tumor cell line after lipopolysaccharide (LPS) (TLR4 agonist) stimulation. In the present study, metformin (MET) treatment, used in combination with temozolomide (TMZ) in two GBM cell lines (U87MG and A172) and stimulated with LPS was analyzed. MET is a drug widely used for the treatment of diabetes and has been repurposed for cancer treatment owing to its anti-proliferative and anti-inflammatory actions. The aim of the study was to investigate MET and LPS treatment in two GBM cell lines with different metabolic statuses. MET treatment led to mitochondrial respiration blunting and oxidative stress with superoxide production in both cell lines, more markedly in U87MG cells. Decreased cell viability after MET + TMZ and MET + LPS + TMZ treatment was observed in both cell lines. U87MG cells exhibited apoptosis after MET + LPS + TMZ treatment, promoting increased ER stress, unfolded protein response, and BLC2 downregulation. LPS stimulation of U87MG cells led to upregulation of SOD2 and genes related to the TLR4 signaling pathway, including IL1B and CXCL8. A172 cells attained upregulated antioxidant gene expression, particularly SOD1, TXN and PRDX1-5, while MET treatment led to cell-cycle arrest. In silico analysis of the TCGA-GBM-RNASeq dataset indicated that the glycolytic plurimetabolic (GPM)-GBM subtype had a transcriptomic profile which overlapped with U87MG cells, suggesting GBM cases exhibiting this metabolic background with an activated inflammatory TLR4 pathway may respond to MET treatment. For cases with upregulated CXCL8, coding for IL8 (a pro-angiogenic factor), combination treatment with an IL8 inhibitor may improve tumor growth control. The A172 cell line corresponded to the mitochondrial (MTC)-GBM subtype, where MET plus an antioxidant inhibitor, such as anti-SOD1, may be indicated as a combinatory therapy.

Mitochondrial transcription factor A (TFAM) is essential for mitochondrial DNA (mtDNA) maintenance and function, but its role in glioblastoma (GBM) remains largely unexplored. Analysis of patient astrocytomas and TCGA datasets has revealed progressive TFAM downregulation with increasing malignancy, with the lowest expression in glycolytic/plurimetabolic (GPM) subtypes. Functional and transcriptomic profiling of mesenchymal GBM cell lines showed that TFAM silencing in GPM-type U87MG cells enhanced proliferation, S-phase entry, reactive oxygen species (ROS) production, and adhesion, while reducing motility. These changes were correlated with upregulation of LDHC and TRAF2 and downregulation of androgen receptor-linked motility genes and LOXL2. By contrast, TFAM loss in mitochondrial (MTC)-type A172 cells caused minimal phenotypic alterations, associated with elevated SOD1 expression and activation of antioxidant, mitochondrial membrane, and survival pathways, alongside suppression of oxidative phosphorylation and vesicle-trafficking genes. TFAM overexpression reduced proliferation in U87MG but had a limited impact on A172 cells. Taken together, these findings establish TFAM as a subtype-specific regulator of GBM cell proliferation, redox balance, and motility. TFAM loss drives a proliferative, ROS-sensitive phenotype in GPM-type cells, while eliciting adaptive, stress-resilient programs in MTC-type cells. This study identifies TFAM and downstream effectors, TRAF2 and LOXL2, as potential therapeutic targets, supporting the development of metabolic subtype-tailored strategies for GBM treatment.

Traumatic brain injury (TBI) is the leading cause of death and neurological disabilities in young adults, representing a significant psychological and economic burden for patients, families, and society. Morbidity and mortality in TBI involve pathophysiological events such as rupture of the blood–brain barrier, neuronal death, and neuroinflammation triggered by the initial trauma and subsequent secondary injuries. A proper understanding of these pathophysiological events involved in TBI is essential to find new targets for the treatment of this disease. The purpose of this study was to analyze the signaling pathways involved in pericontusional brain tissue in severe human TBI. Twenty-two frozen pericontusional brain tissue samples from patients with severe TBI indicated for surgery were analyzed and compared against autopsy brain tissue samples from neurologically healthy donors. The transcriptome analysis by large-scale RNA sequencing (RNA-Seq) was performed in TBI and controls in the exploratory phase. The QuantSeq 3′ mRNA-Seq RNASeq was performed to identify altered gene expression triggered by TBI. Signaling pathway enrichment analysis identified increased expression of gene sets involved in inflammation, angiogenesis, extracellular matrix remodeling, and wound healing pathways, while genes related to ion transport and synaptic transmission were downregulated in TBI relative to controls. Moreover, upregulation of signaling pathways involving TNFα, NFkB, IL6-JAK-STAT, cholesterol homeostasis, inflammatory response, TGFβ, epithelial–mesenchymal transition, coagulation, apoptosis, p53, and angiogenesis was detected with predominant downstream activation of six transcription factors: NFKB2 , FOS , RELB , KLF4 , ATF3 , and EGR2 . Specific brain cell compartment analysis based on gene expression profiles previously reported in single-cell transcriptomes confirmed the upregulation of genes related to microglia, immune cells, and endothelial cells, in contrast to the downregulation of genes related to neurons, astrocytes, and mature oligodendrocyte compartments. Notably, the expression of CCL2 was significant and uniquely correlated with SPHK1 expression, linking inflammatory response to angiogenesis. The transcriptome profile of TBI revealed several differentially expressed genes related to inflammatory response but also to concomitant activation of signaling pathways involved in tissue repair. More specifically, the CCL2-SPHK1 axis was validated at gene and protein expression levels in TBI. Further studies elucidating their role in angiogenesis and promotion of brain tissue repair, together with their potential applicability as therapeutic targets, are warranted.

The human hippocampus comprises spatially organized cell populations, providing a suitable setting for the study of regionally patterned extracellular signaling. Here, we integrated local transcriptomics with GTEx replication, brain-focused Human Protein Atlas analyses, descriptive immunohistochemistry, and pathway-level modeling to define the regional, cellular, and signaling context of ECM glycoproteins in the adult human hippocampus. Across these analyses, RSPO3 was the only ECM glycoprotein with fully reproducible hippocampal enrichment in both cohorts. Shared cross-cohort cell-signature analyses placed RSPO3 in a predominantly positive neuronal transcriptomic context, whereas atlas-based analyses remained compatible with both neuronal and endothelial compartments. IHC across eight brain regions from three individuals provided spatial context and highlighted laminar and perivascular features in the posterior dentate gyrus, but did not support a strong quantitative claim of isolated hippocampal protein enrichment. Pathway analyses prioritized Gαi1/3-Erk as the strongest downstream correlate of the hippocampal RSPO3 signal, whereas Wnt/PCP was weaker, and canonical Wnt/β-catenin was more heterogeneous across cohorts. Together, these findings identify RSPO3 as a reproducible hippocampus-associated extracellular matrix signaling node in the adult human brain and prioritize it for focused mechanistic study.

INTRODUCTION: Type 2 diabetes (T2D) is associated with cognitive decline, but the role of APOE ε4 – a known Alzheimer's risk allele – in cognition among admixed populations with T2D remains unclear. METHODS: We analyzed 883 Brazilian adults with T2D (median age 68 years) from primary care, excluding those with dementia. Cognitive function was assessed using Mini‐Mental State Examination (MMSE), and APOE genotypes were determined. MMSE errors were modeled using negative binomial regression. RESULTS: APOE alleles showed no association with MMSE errors overall. Older age and self‐reported Black/Brown race predicted more errors, whereas higher education and physical activity predicted fewer. Sensitivity analyses indicated a possible inverse association between APOE ε4 and MMSE errors among self‐reported Black/Brown participants. DISCUSSION: APOE ε4 was not associated with cognition in this cohort. The suggestive protective effect observed in Black/Brown participants should be considered hypothesis‐generating, underscoring the need for further research in admixed populations with T2D. Highlights: APOE ε4 was not linked to cognitive errors in the full T2D Brazilian cohort. Trend toward fewer MMSE errors among self‐reported Black/Brown APOE ε4 carriers. Higher education, physical activity, and BMI were protective against MMSE errors. Black/Brown race and older age were associated with more MMSE errors. Results support multifactorial assessment and more studies in admixed T2D populations.

Meningiomas exhibit marked biological heterogeneity that is not fully captured by current histopathological grading. Increasing evidence suggests that mitochondrial metabolism contributes to tumor aggressiveness; however, the molecular mechanisms regulating mitochondrial function in meningiomas remain poorly defined. Here, we investigated the role of mitochondrial transcription factor A (TFAM)–driven mitochondrial biogenesis and translation in meningioma progression. We performed integrative transcriptomic, immunohistochemical, and mitochondrial DNA analyses in a well‐characterized cohort of 91 meningiomas, comprising World Health Organization grade 1 (G1) and grade 2 (G2) tumors with long‐term clinical follow‐up. RNA sequencing identified enrichment for mitochondrial metabolic pathways, including oxidative phosphorylation and ATP metabolism, that was preferentially activated in G2 meningiomas. TFAM and its upstream regulator PGC1α were significantly upregulated at both mRNA and protein levels in G2 tumors and exhibited a positive correlation, consistent with enhanced mitochondrial biogenesis. Although mitochondrial DNA copy number did not differ significantly between grades, G2 meningiomas showed a trend toward increased mitochondrial mass. Notably, G2 meningiomas demonstrated marked enrichment of mitoribosomal genes, including MRPL15 , MRPL35 , MRPL42 and MRPS22 , whose expression correlated positively with TFAM and PGC1α expression levels. Network analysis identified TFAM as a central hub linking mitochondrial biogenesis, translation, and metabolic pathway activation. These findings were independently validated using a publicly available meningioma transcriptomic dataset. Together, our results reveal a TFAM‐centered mitochondrial regulatory program that integrates mitochondrial biogenesis, translational capacity, and oxidative metabolism in higher‐grade meningiomas. This mitochondrial translational axis represents a previously unrecognized mechanism underlying meningioma progression and highlights potential metabolic vulnerabilities for therapeutic intervention.