Journal of neurotrauma
-
Journal of neurotrauma · Nov 2022
Increased fear generalization and amygdala AMPA receptor proteins in chronic traumatic brain injury.
Cognitive impairments and emotional lability are common long-term consequences of traumatic brain injury (TBI). How TBI affects interactions between sensory, cognitive, and emotional systems may reveal mechanisms that underlie chronic mental health comorbidities. Previously, we reported changes in auditory-emotional network activity and enhanced fear learning early after TBI. ⋯ These findings suggest that TBI precipitates maladaptive associative fear generalization rather than non-associative sensitization. Basolateral amygdala (BLA) α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAr) subunits GluA1 and GluA2 levels were analyzed and the FPI-Noise Shock group had increased GluA1 (but not GluA2) levels that correlated with the level of tone fear generalization. This study illustrates a unique chronic TBI phenotype with both a cognitive impairment and increased fear and possibly altered synaptic transmission in the amygdala long after TBI, where stimulus generalization may underlie maladaptive fear and hyperarousal.
-
Journal of neurotrauma · Nov 2022
Review Meta AnalysisMagnetic resonance spectroscopy of traumatic brain injury and subconcussive hits: A systematic review and meta-analysis.
Magnetic resonance spectroscopy (MRS) is a non-invasive technique used to study metabolites in the brain. MRS findings in traumatic brain injury (TBI) and subconcussive hit literature have been mixed. The most common observation is a decrease in N-acetyl-aspartate (NAA), traditionally considered a marker of neuronal integrity. ⋯ NAA was consistently decreased in TBI of all severities, but not in subconcussive hits. Cho and mI were found to be increased in moderate-to-severe TBI but not in mild TBI. Glx and Cr were largely unaffected, but did show alterations in certain conditions.
-
Journal of neurotrauma · Nov 2022
The impact of high fat consumption on neurological functions following a traumatic brain injury in rats.
Traumatic brain injury (TBI) and obesity are two common conditions in modern society; both can impair neuronal integrity and neurological function. However, it is unclear whether the coexistence of both conditions will worsen outcomes. Therefore, in a rat model, we aimed to investigate whether the coexistence of TBI and a high-fat diet (HFD) has an additive effect, leading to more severe neurological impairments, and whether they are related to changes in brain protein markers of oxidative stress, inflammation, and synaptic plasticity. ⋯ In rats without TBI, HFD increased the pre-synaptic protein synaptophysin. In rats with TBI, HFD resulted in worsened sensory and memory function, an increase in activated macrophages, and a decrease in the endogenous antioxidant manganese superoxide dismutase (MnSOD). Our findings suggest that the additive effect of HFD and TBI worsens short term memory and sensation deficits, and may be driven by enhanced oxidative stress and inflammation.
-
Journal of neurotrauma · Nov 2022
ReviewCerebral Autoregulation Monitoring in Traumatic Brain Injury: An Overview of Recent Advances in Personalized Medicine.
Impaired cerebral autoregulation (CA) in moderate/severe traumatic brain injury (TBI) has been identified as a strong associate with poor long-term outcomes, with recent data highlighting its dominance over cerebral physiological dysfunction seen in the acute phase post-injury. With advances in bedside continuous cerebral physiological signal processing, continuously derived metrics of CA capacity have been described over the past two decades, leading to improvements in cerebral physiological insult detection and development of novel personalized approaches to TBI care in the intensive care unit (ICU). ⋯ The CA-based personalized targets, such as optimal cerebral perfusion pressure (CPPopt), lower/upper limit of regulation (LLR/ULR), and individualized intracranial pressure (iICP) are positioned to change the way we care for patients with TBI in the ICU, moving away from the "one treatment fits all" paradigm of current guideline-based therapeutic approaches toward a true personalized medicine approach tailored to the individual patient. Future perspectives regarding research needs in this field are also discussed.