Background/Objectives: Traumatic brain injury (TBI) is a global leading cause of disability and death, with millions of new cases added each year. Oxidative stress significantly exacerbates primary TBI, leading to increased levels of intracerebral cell death, tissue loss, and long-term functional deficits in surviving patients. Catalase and superoxide dismutase (SOD) mitigate oxidative stress and play a critical role in dampening injury severity. This study examines the neuroprotective effects of the novel antioxidant alpha lipoic acid-based therapeutic, CMX-2043, on antioxidant enzymes in a preclinical TBI model via various drug administration routes. Methods: Piglets (n = 28) underwent cortical controlled impact to induce moderate–severe TBI and were assigned to placebo (n = 10), subcutaneous CMX-2043 (SQ, 10 mg/kg; n = 9), or intravenous CMX-2043 (IV, 9 mg/kg; n = 9) treatment groups. Treatments began 1 h after TBI induction and continued for 5 days. MRI was performed throughout the study period to evaluate brain recovery. Blood was collected at 1, 7, and 42 days post-TBI, and liver and brain tissues were collected at 42 days post-TBI to measure catalase and SOD activity. Results: CMX-2043 IV-treated piglets showed 46.3% higher hepatic catalase activity than placebo (p = 0.0038), while the SQ group did not show significant changes in hepatic catalase activity compared to placebo. In the brain, SQ-treated piglets had significantly higher catalase activity than both IV (p = 0.0163) and placebo (p = 0.0003) groups (45.8340 ± 3.0855, 36.4822 ± 1.5558, 31.6524 ± 1.3129 nmol/min/mg protein for SQ, IV, and placebo, respectively), while IV-treated piglets did not show significant changes compared to placebo. IV-treated piglets did exhibit 39.3% higher brain SOD activity than placebo (p = 0.0148), while the SQ group did not show a significant change. CMX-2043 treatment did not alter plasma antioxidant enzyme activity during the study period. Importantly, within CMX-2043 treated TBI groups, piglets with significantly decreased lesion volumes, midline shift, and combined swelling and atrophy had better brain recovery, determined by MRI on day 1, 7, and 42 days post-injury TBI, exhibited higher brain catalase activity at 42 days post-injury TBI regardless of administration route, suggesting a link between improved recovery and sustained local catalase activity. Conclusions: This study highlights the impact of administration route on tissue-specific antioxidant responses, with IV administration enhancing liver catalase and brain SOD activity, while SQ administration primarily elevated brain catalase activity. In addition, this study shows an association between increased brain catalase activity and decreased TBI brain lesioning, midline shift, and combined swelling and atrophy, thus emphasizing the role of antioxidant defenses in neuroprotection post-injury.

Human neural stem cells (hNSCs) possess significant therapeutic potential for the treatment of traumatic brain injury (TBI), a leading cause of global death and disability. Recent pre-clinical studies have shown that hNSCs reduce tissue damage and promote functional recovery through neuroprotective and regenerative signaling and cell replacement. Yet the overall efficacy of hNSCs for TBI indications remains unclear. Therefore, this systematic review aims to evaluate hNSC interventions compared with controls in pre-clinical TBI models. Through this process, variations in hNSC administration protocols were consolidated, and key knowledge gaps were identified. Meta-analysis was applied to primary outcomes of lesion volume, Morris Water Maze (MWM) performance, modified Neurological Severity Scores (mNSS), and the rotarod task. Narrative review of secondary outcomes included hNSC survival and differentiation, endogenous neuron survival, axonal injury, and inflammation. Overall, hNSC intervention reduced lesion volume, enhanced MWM performance, and led to trending decreases in acute and chronic neurological deficits at acute and chronic time points. These results suggest hNSCs demonstrate clear efficacy in pre-clinical TBI models. However, further studies are needed to address key questions regarding optimal hNSC administration (e.g., dosing, treatment window) and underlying mechanisms of action prior to progressing to human clinical trials.

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, and is indiscriminate in who it affects, including children. Although there are currently no Food and Drug Administration-approved therapeutics, promising results from recent induced pluripotent stem cell-derived neural stem cell (iNSC) studies have demonstrated decreased tissue damage and functional deficits in pre-clinical TBI models. Moreover, while the rest has been traditionally identified as the standard of care following TBI, research now suggests that physical activity postinjury may significantly enhance neuroprotective and regenerative signaling in patients. Combining these two therapies may therefore synergistically improve recovery outcomes in TBI patients. In this study, we evaluated the combined therapeutic efficacy of iNSCs and structured treadmill walking on cellular, tissue, and functional recovery in a translational pediatric pig TBI model. One-month-old piglets received a controlled cortical impact-induced TBI and were randomly assigned to either a PBS (n = 4), PBS + treadmill (n = 4), iNSC (n = 4), or iNSC + treadmill (n = 4) treatment group. Piglets received intraparenchymal transplantations of either iNSCs or PBS 5 days post-TBI. At 1-week post-transplantation, piglets assigned to the treadmill treatment groups began a 12-week progressive walking regimen. Motor function and open field behavior assessments were performed pre-TBI and 12 weeks post-transplantation. Magnetic resonance imaging (MRI) and histological evaluation of collected brain tissue were performed 12 weeks post-transplantation. Immunohistochemistry revealed long-term survival, engraftment, and differentiation of transplanted iNSCs into neurons, astrocytes, and oligodendrocytes in treated piglets. Furthermore, iNSC + treadmill treatment showed increased endogenous neuron and oligodendrocyte survival, increased proliferation of neuroblasts, and decreased populations of reactive astrocytes and immune cells in TBI brain tissue. MRI analysis revealed a significant reduction in lesion volume, midline shift, and white matter degradation with preserved cerebral blood flow following both iNSC and iNSC + treadmill interventions. These cellular and tissue-level effects corresponded with significant motor function recovery as seen through increased step and stride length with decreased stance percentage and time. During open field behavioral assessments, iNSC and iNSC + treadmill-treated piglets demonstrated improved exploratory behaviors. These findings suggest that the combination of iNSCs with structured treadmill walking significantly enhanced TBI recovery beyond the therapeutic potential of iNSCs or exercise alone. Therefore, this novel combination therapy needs to be further explored as a potential transformative treatment option for pediatric TBI patients.

Traumatic brain injury (TBI) represents a major global health issue contributing to significant disability and mortality. The TBI-induced secondary injury cascade, characterized by neuroinflammation, neural cell death, and tissue damage, results in lifelong functional deficits. Alpha- N -[(R)-1, 2-dithiolane-3-pentanoyl] l -glutamyl- l -alanine (CMX-2043) is a novel alpha lipoic acid (ALA)-based therapeutic that has neuroprotective, anti-apoptotic, and anti-inflammatory properties that mitigate cellular, tissue, and functional deficits following TBI. In this study, we evaluated the therapeutic efficacy of CMX-2043 on neural injury severity and functional recovery in a clinically relevant porcine TBI model. CMX-2043 was administered 1-h post-TBI subcutaneously (SQ; n = 8) or intravenously (IV; n = 8) for a total of 5 days. Control piglets (placebo; n = 11) received saline subcutaneously. Magnetic resonance imaging (MRI), immunohistochemistry analysis, modified Rankin Scale (mRS) neurological evaluation, and social recognition testing (SRT) were evaluated up to 42 days post-TBI. MRI revealed that SQ and IV CMX-2043 administration reduced hemispheric swelling and atrophy, lesion volume, midline shift, and intracerebral hemorrhage and preserved diffusivity, cerebral blood flow, and white matter integrity. CMX-2043-mediated neuroprotection and regeneration were indicated by increased neural cell density, decreased neuroinflammation, and enhanced neurogenesis following SQ and IV administration. These cellular and tissue-level changes corresponded with reduced neurological deficits and rapid cognitive recovery as indicated by improved mRS and SRT results, respectively. Collectively, these results observed in a translational large animal porcine model suggest that CMX-2043 holds significant clinical value to potentially mitigate TBI pathophysiology and promote functional recovery.