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Gomez-Pinilla, F.

Publications and source records attributed to Gomez-Pinilla, F..

9 recordsLinked to original sources

Probiotic treatment causes sex-specific neuroprotection after traumatic brain injury in mice

BackgroundRecent studies have shed light on the potential role of gut dysbiosis in shaping traumatic brain injury (TBI) outcomes. Changes in the levels and types of Lactobacillus bacteria present might impact the immune system disturbances, neuroinflammatory responses, anxiety and depressive-like behaviors, and compromised neuroprotection mechanisms triggered by TBI. ObjectiveThis study aimed to investigate the effects of a daily pan-probiotic (PP) mixture in drinking water containing strains of Lactobacillus plantarum, L. reuteri, L. helveticus, L. fermentum, L. rhamnosus, L. gasseri, and L. casei, administered for either two or seven weeks before inducing TBI on both male and female mice. MethodsMice were subjected to controlled cortical impact (CCI) injury. Short-chain fatty acids (SCFAs) analysis was performed for metabolite measurements. The taxonomic profiles of murine fecal samples were evaluated using 16S rRNA V1-V3 sequencing analysis. Histological analyses were used to assess neuroinflammation and gut changes post-TBI, while behavioral tests were conducted to evaluate sensorimotor and cognitive functions. ResultsOur findings suggest that PP administration modulates the diversity and composition of the microbiome and increases the levels of SCFAs in a sex-dependent manner. We also observed a reduction of lesion volume, cell death, and microglial and macrophage activation after PP treatment following TBI in male mice. Furthermore, PP-treated mice show motor function improvements and decreases in anxiety and depressive-like behaviors. ConclusionOur findings suggest that PP administration can mitigate neuroinflammation and ameliorate motor and anxiety and depressive-like behavior deficits following TBI. These results underscore the potential of probiotic interventions as a viable therapeutic strategy to address TBI-induced impairments, emphasizing the need for gender-specific treatment approaches.

neuroscience↗

Thyroid Hormone T4 Mitigates Traumatic Brain Injury via Dynamically Remodeling Cell Type Specific Genes and Pathways

BackgroundThe complex pathology of mild traumatic brain injury (mTBI) is a main contributor to the difficulties in achieving a successful therapeutic regimen. Thyroxine (T4) administration has been shown to prevent the cognitive impairments induced by mTBI in mice. MethodTo understand the underlying mechanism, we carried out a single cell transcriptomic study to investigate the spatiotemporal effects of T4 on individual cell types in the hippocampus and frontal cortex at three post-injury stages. FindingsOur multi-tissue multi-stage results showed that T4 treatment altered the proportions and transcriptomes of numerous cell types across tissues and timepoints, particularly oligodendrocytes, astrocytes, and microglia, which are crucial for injury repair. T4 also reversed the expression mTBI-affected genes such as Ttr, mt-Rnr2, Ggn12, Malat1, Gnaq, and Myo3a, as well as numerous pathways such as cell/energy/iron metabolism, immune response, nervous system, and cytoskeleton-related pathways. Cell-type specific network modeling revealed that T4 mitigated select mTBI-perturbed dynamic shifts in subnetworks related to cell cycle, stress response, and RNA processing in oligodendrocytes. Cross cell-type ligand-receptor networks recapitulated the roles of App, Hmgb1, Fn1, and Tnf in mTBI, the latter two ligands having been previously identified as TBI network hubs. mTBI and/or T4 signature genes were enriched for human genome-wide association study (GWAS) candidate genes for cognitive, psychiatric and neurodegenerative disorders related to mTBI, supporting T4 as a potential mTBI treatment. InterpretationOur systems-level approach elucidated the temporal and spatial dynamic reprogramming of cell-type specific genes, pathways, and networks, as well as cell-cell communications through which T4 mitigates cognitive dysfunction induced by mTBI. FundingThis work was funded by NIHR01NS117148 to X.Y. and F.G.P. Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSDysfunction in the brain resulting from traumatic brain injury can display immediately as well as several years post-injury. It also impacts various brain regions, including the hippocampus and frontal cortex, which are linked to distinct disease pathologies. The complexity of spatiotemporal and molecular dynamics of perturbation caused by TBI hinder our ability to establish an effective therapeutic approach. Recently, thyroid hormone poses promise as a potential therapeutic target based on our previous scRNA-seq studies. Yet, the mechanisms by which T4 alleviates mTBI, specifically those related to spatial, temporal, and cell-type specificity, remain unexplored. Added value of this studyWe examined the impact of T4 intervention in mitigating mTBI by investigating the transcriptome and functional pathways across two affected brain regions, the frontal cortex and hippocampus, in different stages of injury. Utilizing a systems biology approach, we conducted within- and between-cell-type network modeling, cell-cell communication and integrating human genome-wide association studies (GWAS) analysis. This comprehensive strategy aimed to elucidate the cellular and molecular mechanisms through which T4 averts cognitive impairments induced by mTBI. Implications of all the available evidenceOur findings offer molecular evidence that the administration of T4 impacts a wide range of genes, biological processes, and networks, thereby preventing the advancement of mTBI-induced brain dysfunction and associated diseases. This comprehensive impact of T4 suggests potential advantages in efficacy compared to other therapeutic options that concentrate on specific pathways and targets.

neuroscience↗

JSTA: joint cell segmentation and cell type annotation for spatial transcriptomics

RNA hybridization based spatial transcriptomics provides unparalleled detection sensitivity. However, inaccuracies in segmentation of image volumes into cells cause misassignment of mRNAs which is a major source of errors. Here we develop JSTA, a computational framework for Joint cell Segmentation and cell Type Annotation that utilizes prior knowledge of cell-type specific gene expression. Simulation results show that leveraging existing cell type taxonomy increases RNA assignment accuracy by more than 45%. Using JSTA we were able to classify cells in the mouse hippocampus into 133 (sub)types revealing the spatial organization of CA1, CA3, and Sst neuron subtypes. Analysis of within cell subtype spatial differential gene expression of 80 candidate genes identified 43 with statistically significant spatial differential gene expression across 61 (sub)types. Overall, our work demonstrates that known cell type expression patterns can be leveraged to improve the accuracy of RNA hybridization based spatial transcriptomics while providing highly granular cell (sub)type information. The large number of newly discovered spatial gene expression patterns substantiates the need for accurate spatial transcriptomics measurements that can provide information beyond cell (sub)type labels.

systems biology↗

Multi-tissue Multi-omics Nutrigenomics Indicates Context-specific Effects of DHA on Rat Brain

ScopeWe explored the influence of DHA on cardiometabolic and cognitive phenotypes, and multiomic alterations in the brain under two metabolic conditions to understand context-specific nutritional effects. Methods and ResultsRats were randomly assigned to a DHA-rich or a control chow diet while drinking water or high fructose solution, followed by profiling of metabolic and cognitive phenotypes and the transcriptome and DNA methylome of the hypothalamus and hippocampus. DHA reduced serum triglyceride and improved insulin resistance and memory exclusively in the fructose-consuming rats. In hippocampus, DHA affected genes related to synapse functions in the chow group but immune functions in the fructose group; in hypothalamus, DHA altered immune pathways in the chow group but metabolic pathways in the fructose group. Network modeling revealed context-specific regulators of DHA effects, including Klf4 and Dusp1 for chow condition and Lum, Fn1, and Col1a1 for fructose condition in hippocampus, as well as Cyr61, JunB, Ier2, and Pitx2 under chow condition and Hcar1, Cdh1, and Osr1 under fructose condition in hypothalamus. ConclusionDHA exhibits differential influence on epigenetic loci, genes, pathways, and metabolic and cognitive phenotypes under different dietary contexts, supporting population stratification in DHA studies to achieve precision nutrition.

systems biology↗

Secondary single-cell transcriptomic analysis reveals common molecular signatures of cerebrovascular injury between traumatic brain injury and aging

Cerebrovascular injury is a common pathological feature of a spectrum of neurological disorders including traumatic brain injury (TBI), stroke, Alzheimers disease (AD), as well as aging. Vascular manifestations among these conditions are similar indeed, including the breakdown of the blood-brain barrier (BBB). However, whether there is a common molecular mechanism underlying the vascular changes among these conditions remains elusive. Here, we report secondary transcriptomic analysis on cerebrovascular cells based single-cell RNA-seq datasets of mouse models of mild TBI and aging, with a focus on endothelial cells and pericytes. We identify several molecular signatures commonly found between mTBI and aging vasculature, including Adamts1, Rpl23a, Tmem252, Car4, Serpine2, and Ndnf in endothelial cells, and Rps29 and Sepp1 in pericytes. These markers may represent the shared endophenotype of microvascular injury and be considered as cerebrovascular injury responsive genes. Additionally, pathway analysis on differentially expressed genes demonstrated alterations in common pathways between mTBI and aging, including vascular development and extracellular matrix pathways in endothelial cells. Hence, our analysis suggests that cerebrovascular injury triggered by different neurological conditions may share common molecular signatures, which may only be detected at the single-cell transcriptome level.

neuroscience↗

Microvascular Injury in Mild Traumatic Brain Injury Accelerates Alzheimer-like Pathogenesis in Mice

IntroductionTraumatic brain injury (TBI) is considered as the most robust environmental risk factor for Alzheimers disease (AD). Besides direct neuronal injury and neuroinflammation, vascular impairment is also a hallmark event of the pathological cascade after TBI. However, the vascular connection between TBI and subsequent AD pathogenesis remains underexplored. MethodsWe established a closed-head mild TBI (mTBI) model in mice with controlled cortical impact, and examined the time courses of microvascular injury, blood-brain barrier (BBB) dysfunction, gliosis and motor function impairment in wild type C57BL/6 mice. We also determined the brain clearance of {beta}-amyloid, as well as amyloid pathology and cognitive functions after mTBI in the 5xFAD mouse model of AD. ResultsmTBI induced microvascular injury with BBB breakdown, pericyte loss and cerebral blood flow reduction in mice, which preceded gliosis. mTBI also impaired brain amyloid clearance via the vascular pathways. More importantly, mTBI accelerated amyloid pathology and cognitive impairment in the 5xFAD mice. DiscussionOur data demonstrated that microvascular injury plays a key role in the pathogenesis of AD after mTBI. Therefore, restoring vascular functions might be beneficial for patients with mTBI, and potentially reduce the risk of developing AD.

neuroscience↗

Differential Metabolic and Multi-tissue Transcriptomic Responses to Fructose Consumption among Genetically Diverse Mice

High fructose intake is a major risk for metabolic syndrome; however, its effects seem to vary across individuals. To determine main factors involved in the inter-individual responses to fructose, we fed inbred mouse strains C57BL/6J (B6), DBA/2J (DBA) and FVB/NJ (FVB) with fructose. DBA mice showed the highest susceptibility to gain adiposity and glucose intolerance. Elevated insulin was found in DBA and FVB mice, and cholesterol levels were uniquely elevated in B6 mice. The transcriptional profiles of liver, hypothalamus, and adipose tissues showed strain- and tissue-specific pathways altered by fructose, such as fatty acid and cholesterol pathways for B6 and PPAR signaling for DBA in liver, and oxidative phosphorylation for B6 and protein processing for DBA in hypothalamus. Using network modeling, we predicted potential strain-specific key regulators of fructose response such as Fgf21 (DBA) and Lss (B6) in liver, and validated strain-biased responses as well as the regulatory actions of Fgf21 and Lss in primary hepatocytes. Our findings support that fructose perturbs individualized tissue networks and pathways and associates with distinct features of metabolic dysfunctions across genetically diverse mice. Our results elucidate the molecular pathways and gene regulatory mechanisms underlying inter-individual variability in response to high fructose diet.

systems biology↗

Host Genetic Background and Gut Microbiota Contribute to Differential Metabolic Responses to High Fructose Consumption in Mice

BackgroundIt is unclear how high fructose consumption induces disparate metabolic responses in genetically diverse mouse strains. ObjectiveWe aim to investigate whether the gut microbiota contributes to differential metabolic responses to fructose. MethodsEight-week-old male C57BL/6J (B6), DBA/2J (DBA), and FVB/NJ (FVB) mice were given 8% fructose solution or regular water (control) for 12 weeks. The gut microbiota composition in cecum and feces was analyzed using 16S rDNA sequencing, and PERMANOVA was used to compare community across mouse strains, treatments, and time points. Microbiota abundance was correlated with metabolic phenotypes and host gene expression in hypothalamus, liver and adipose tissues using Biweight midcorrelation. To test the causal role of the gut microbiota in determining fructose response, we conducted fecal transplants from B6 to DBA mice and vice versa for 4 weeks, as well as gavaged antibiotic-treated DBA mice with Akkermansia for 9 weeks, accompanied with or without fructose treatment. ResultsCompared to B6 and FVB, DBA mice had significantly higher Firmicutes/Bacteroidetes ratio and lower baseline levels of Akkermansia and S24-7 (P < 0.05), accompanied by metabolic dysregulation after fructose consumption. Fructose altered specific microbial taxa in individual mouse strains, such as a 7.27-fold increase in Akkermansia in B6 and 0.374-fold change in Rikenellaceae in DBA (FDR < 5%), which demonstrated strain-specific correlations with host metabolic and transcriptomic phenotypes. Fecal transplant experiments indicated that B6 microbes conferred resistance to fructose-induced weight gain in DBA mice (F = 43.1, P < 0.001), and Akkermansia colonization abrogated the fructose-induced weight gain (F = 17.8, P <0.001) and glycemic dysfunctions (F = 11.8, P = 0.004) in DBA mice. ConclusionsOur findings support that differential microbiota composition between mouse strains is partially responsible for host metabolic sensitivity to fructose, and that Akkermansia is a key bacterium that confers resistance to fructose-induced metabolic dysregulation.

systems biology↗

Single Cell Molecular Alterations Reveal Pathogenesis and Targets of Concussive Brain Injury

The complex neuropathology of traumatic brain injury (TBI) is difficult to dissect in the hippocampus considering the convoluted hippocampal cytoarchitecture. As a major casualty of TBI, hippocampal dysfunction results in cognitive decline that may escalate to other neurological disorders, and the molecular basis is hidden in the genomic programs of individual hippocampal cells. Using the unbiased single cell sequencing method Drop-seq, we uncovered the hippocampal cell types most sensitive to concussive mild TBI (mTBI) as well as the vulnerable genes, pathways and cell-cell interactions predictive of disease pathogenesis in a cell-type specific manner, revealing hidden pathogenic mechanisms and potential targets. Targeting Ttr, encoding the thyroid hormone T4 transporter transthyretin, mitigated the genomic and behavioral abnormalities associated with mTBI. Single cell genomics provides unique evidence about altered circuits and pathogenic pathways, and pinpoints new targets amenable to therapeutics in mTBI and related disorders.

systems biology↗