Biology subjects

Kara, G.

Publications and source records attributed to Kara, G..

4 recordsLinked to original sources

bioRxiv2026

Intranasal CRISPR- lipid nanoparticles targeting MAPK9 reduce neuroinflammation after traumatic brain injury

Traumatic brain injury (TBI) triggers a sustained neuroinflammatory response driven by activated microglia, which contributes to secondary injury and long-term neurological dysfunction. Therapeutic reprogramming of microglial activation from a pro-inflammatory (M1-like) to a reparative (M2-like) phenotype represents a promising strategy; however, the lack of cell-specific targeting within an injured brain has limited clinical translation. Here, we developed a targeted gene-editing nanotherapy to modulate post-traumatic innate immune responses. Lipid nanoparticles (LNPs) encapsulating CRISPR-Cas12a components were engineered to target mitogen-activated protein kinase-9 (MAPK9), a key regulator of pro-inflammatory signaling, and were conjugated with an Iba-1 antibody (Iba-1-CRISPR-LNPs) to enable selective targeting of microglia. In vitro, MAPK9 editing in primary macrophages inhibited M1 polarization and promoted an M2-like phenotype, leading to reduced production of pro-inflammatory cytokines. In a TBI mouse model, intranasal administration of Iba-1-CRISPR-LNPs achieved efficient delivery to the injured brain, with selective localization in Iba-1+ microglia. MAPK9 CRISPR targeting significantly attenuated microglial activation, reduced central and peripheral inflammatory responses, and decreased pro-inflammatory cytokine levels. Importantly, this approach demonstrated a favorable safety profile, with no detectable toxicity across major organs. Collectively, these findings establish a non-viral, intranasal CRISPR-based strategy for cell-specific modulation of neuroinflammation following TBI. Targeted genome editing of MAPK9 effectively reprograms microglial activation and attenuates acute inflammatory responses, highlighting its potential as a promising and translationally relevant therapeutic platform for TBI and related neuroinflammatory disorders.

neuroscience↗

bioRxiv2026

Simulated spaceflight disrupts the immune-gut-brain axis and drives sex-dependent neuroinflammation, axonal injury, and behavioral deficits.

Simulated spaceflight perturbs multiple organ systems, yet the integrated impact of spaceflight-relevant stressors on the immune-gut-brain axis remains poorly defined. We used a ground-based model combining hindlimb unloading (HU) with low-dose ionizing radiation (IR; 50 or 100cGy) to quantify neuropathology, peripheral immune phenotypes, intestinal barrier integrity, and behavioral performance in male and female C57BL/6 mice. HU and/or IR induced region-selective neurodegenerative changes consistent with axonal injury across the cortex and major white-matter tracts. In the somatosensory cortex, MAP-2+ neurons were reduced and SMI-312-labeled axonal injury increased, lowering the intact-to-dystrophic axonal area ratio. Long-range fiber pathways (corpus callosum, cingulate gyrus, external capsule) showed robust axonal damage accompanied by gliosis, with elevated Iba-1+ microglia and GFAP+ astrocytes most prominent after HU+IR (100cGy). Peripheral immunophenotyping revealed a sustained, sex-dependent innate inflammatory bias, with expanded CD11b+ myeloid cells and increased TNF-+ myeloid activation after IR and IR+HU, alongside maladaptive T-cell polarization despite largely unchanged total CD8+ and CD4+ frequencies. In parallel, the gut exhibited architectural remodeling and barrier failure, including altered mucin profiles, reduced ZO-1 tight-junction labeling, and increased CD45+ leukocyte infiltration across the jejunum, ileum, and colon. Behavioral assays demonstrated sex-dependent deficits spanning affective, motor, and cognitive domains, including increased anxiety- and depressive-like behaviors, impaired rotarod performance, reduced recognition memory, and less efficient spatial strategies. Overall, these findings identify a sex-dependent immune-gut-brain vulnerability in which combined HU and low-dose IR drive gut barrier breakdown and immune imbalance that coincide with neuroinflammatory axonopathy and measurable neurobehavioral dysfunction.

neuroscience↗

bioRxiv2025

Telomerase mRNA-Lipid nanoparticles attenuate neuroinflammation after traumatic brain injury in mice

Traumatic brain injury (TBI) is a leading cause of chronic neurological disability, yet no disease-modifying therapy exists. Emerging evidence indicates that TBI activates cellular aging programs, including telomere erosion and persistent inflammation, that contribute to progressive neurodegeneration. Telomerase reverse transcriptase (TERT) preserves telomere homeostasis and provides cytoprotective effects in the central nervous system, but has not been therapeutically targeted after TBI. Here, we developed an mRNA nanotherapy consisting of mouse TERT mRNA encapsulated in lipid nanoparticles (mTERT-LNPs) and evaluated it in a controlled cortical impact model of moderate TBI. We first established that TBI transiently disrupts TERT biology, with reduced cortical TERT mRNA and shortened telomeres at 3 days post-injury (dpi), followed by partial recovery by 14 dpi. mTERT-LNPs were well tolerated in vitro and in vivo. Following intravenous delivery in the acute post-injury window, LNPs localized to the injured brain and displayed expected peripheral biodistribution. A single systemic dose increased cortical TERT mRNA and protein and partially restored telomere length at 3 dpi. TERT mRNA delivery significantly reduced Iba1+ microglial activation and suppressed pro-inflammatory cytokines, with modest increases in anti-inflammatory markers. Systemically, mTERT-LNPs lowered serum C-reactive protein and malondialdehyde, indicating reduced peripheral inflammation and oxidative stress, without adverse effects on body weight or peripheral organ histology. Several outcomes showed sex-dependent patterns. Collectively, these data provide the first in vivo evidence that telomerase therapy can modulate telomere biology and neuroinflammation after TBI, supporting mRNA-LNP-mediated TERT restoration as a scalable, mechanistically grounded strategy for disease modification in TBI and related disorders. Significant statementTraumatic brain injury (TBI) can initiate progressive brain changes that worsen long after the initial impact, and no therapy directly slows or prevents this decline. A key contributor may be "accelerated aging" in injured tissue, including telomere damage (protective chromosome ends) and persistent neuroinflammation driven by activated immune cells. This study is significant because it tests a targeted way to disrupt these processes by restoring telomerase reverse transcriptase (TERT), which helps maintain telomeres and cellular resilience. Using a clinically validated mRNA-lipid nanoparticle platform, a single intravenous dose increased brain TERT, partially restored telomere length, and reduced neuroinflammation and systemic oxidative stress without obvious toxicity. These findings connect telomere dysfunction to a scalable disease-modifying strategy for TBI and related neurodegenerative conditions.

neuroscience↗

bioRxiv2025

Sex-specific effects of fecal microbiota transplantation on TBI-exacerbated Alzheimer's pathology in mice

BackgroundTraumatic brain injury (TBI) accelerates Alzheimers disease (AD) pathology and neuroinflammation, potentially via gut-brain axis disruptions. Whether restoring gut microbial homeostasis mitigates TBI-exacerbated AD features remains unclear, particularly with respect to sex differences. ObjectiveThe goal of our study was to test whether fecal microbiota transplantation (FMT) modifies amyloid pathology, neuroinflammation, gut microbial composition, metabolites, and motor outcomes in male and female 5xFAD mice subjected to TBI. MethodsMale and female 5xFAD mice received sham treatments or controlled cortical impact, followed 24 hours later by vehicle (VH) or sex-matched FMT from C57BL/6 donors. Assessments at baseline, 1, and 3 days post-injury included Thioflavin-S and 6E10 immunostaining for A{beta}, Iba-1 and GFAP for glial activation, lesion volume, rotarod performance, 16S rRNA sequencing for microbiome profiling, serum short-chain fatty acids (SCFAs), and gut histology. ResultsTBI increased cortical and dentate gyrus A{beta} burden, with females showing greater vulnerability. FMT reduced A{beta} deposition in sham animals and shifted plaque morphology but did not attenuate TBI-induced amyloid escalation. FMT differentially modulated glial responses by sex and region (reduced microgliosis in males) without altering lesion volume. Rotarod performance was better in sham females compared to males and declined in FMT-treated TBI females. Fecal microbiome alpha diversity and richness were unchanged, while beta diversity revealed marked, time-dependent community shifts after TBI that were slightly altered by FMT. Gut morphology remained broadly intact, but crypt width increased after TBI, particularly in males. ConclusionIn 5xFAD mice, TBI drives sex-dependent worsening of amyloid pathology, neuroinflammation, and dysbiosis. Acute FMT partially restores microbial composition and plaque features in sham animals but fails to reverse TBI-induced neuroinflammation or motor deficits. These findings underscore the context- and sex-dependence of microbiome interventions and support longer-term, sex-specific strategies for AD with comorbid TBI.

neuroscience↗