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Bergamino, M.

Publications and source records attributed to Bergamino, M..

3 recordsLinked to original sources

Subacute and Chronic Cognitive and Cerebrovascular Functional Consequences of Mild Traumatic Brain Injury in Rats

Traumatic brain injury (TBI) is the main cause of death and disability in the United States in people younger than 35 years old and is a common cause of wartime injuries. Mild TBI (mTBI) is a predisposing factor for later development of dementia and cerebrovascular disease. Aerobic exercise was reported to improve cognitive function in chronic TBI through improved vascular function. The aims of the study are to characterize and correlate the subacute (10 weeks) and chronic (12 months) cognitive and cerebrovascular functional impairment following mTBI and evaluate the modulating effect of exercise early or late following mTBI on these changes. Sprague-Dawley rats received midline fluid percussion injury or sham procedure and followed for 10 weeks or 12 months with a subgroup of mTBI rats undergoing 5-week treadmill aerobic exercise 2 weeks (early) or 10 months (late) post-injury for 6 weeks. Cognitive function was assessed using novel object recognition (NOR) and novel object location (NOL) tests. Regional cerebral blood volume (CBV) and cerebrovascular reactivity following hypercapneic stimulation (CVR) using contrast magnetic resonance imaging (MRI) and ex vivo pial artery vasoreactivity to intraluminal pressure, angiotensin II and diethylenetriamine NONOate (DETA NONOate) were measured. There was no difference in NOR or NOL at 10 weeks between mTBI and sham. NOR, but not NOL, was reduced in mTBI rats at 12 months. CBV at 10 weeks was higher in the primary somatosensory trunk cortex (trunk) and dentate gyrus regions in mTBI, but not at 12 months. CVR was lower in the trunk region of mTBI rats at 12 months. Compared to sham response at 10 weeks, there was impaired arterial constriction response to 90 mm Hg intraluminal pressure in mTBI rats at 10 weeks and in sham and mTBI rats at 12 months, with no difference seen in response to angiotensin II or DETA-NONOate exposure. There was no correlation between cognitive and vascular outcomes at 10 weeks or 12 months. Early or late exercise did not affect 12-month cognitive or vascular function following mTBI. The study showed chronic impairment in short-term memory cognitive function, regional cerebrovascular reactivity and early onset of impaired cerebrovascular myogenic response in rats subjected to mTBI. The findings of persistent cognitive and cerebrovascular impairment in this animal model enhance our understanding of the long-term consequence of mTBI.

neuroscience↗

Distinct nigral and brainstem pathology markers map onto separable subthalamic electrophysiological signatures in Parkinson's disease

Subthalamic local field potentials (LFPs) are increasingly used as physiomarkers of the symptomatic state in Parkinsons disease, but their relationship to the underlying neurodegenerative pathology remains unclear. Here, we combined OFF-medication subthalamic LFP recordings with quantitative MRI markers of nigral and brainstem pathology in 33 people with Parkinsons disease. Distinct pathological markers mapped onto dissociable electrophysiological components. Substantia nigra pars compacta susceptibility was associated with increased occupancy, duration and rate of low-{beta} bursts, whereas nigral free water was associated with greater low-frequency aperiodic offset and a steeper slope. Pedunculopontine nucleus free-water- corrected axial diffusivity was selectively associated with high-frequency aperiodic activity, and this relationship strengthened with increasing nigral susceptibility, consistent with dopaminergic-state- dependent influences of extranigral pathology on subthalamic physiology. Only low-frequency aperiodic offset was also associated with contralateral bradykinesia. These findings indicate that the subthalamic LFP is not a unitary readout of dopamine loss or motor state, but an integrated physiological signal in which pathology across interconnected systems is expressed through separable oscillatory and aperiodic components. Chronically implanted devices may therefore provide physiological readouts of underlying disease biology alongside control signals for adaptive therapy.

neuroscience↗

Insights into cisplatin-induced neurotoxicity and mitochondrial dysfunction in Caenorhabditis elegans

Cisplatin is the most common drug in first-line chemotherapy against solid tumors. We and others have previously used the nematode Caenorhabditis elegans to identify genetic factors influencing the sensitivity and resistance to cisplatin. In this study, we take advantage of C. elegans to explore cisplatin effects on mitochondrial functions and investigate cisplatin-induced neurotoxicity through a high-resolution semi-automated system for evaluating locomotion. Firstly, we report that a high-glucose diet sensitizes C. elegans to cisplatin at the physiological level and that mitochondrial CED-13 protects the cell from cisplatin-induced oxidative stress. Additionally, by assessing mitochondrial function with a Seahorse Analyzer, we observed a detrimental additive effect of cisplatin and glucose in mitochondrial respiration. Secondly, since we previously found that catechol-O-methyltransferases (involved in dopamine degradation) were upregulated upon cisplatin exposure, we studied the protective role of the FDA-approved drug dopamine against cisplatin-induced neurotoxicity. To implement the use of the Tierpsy Tracker system for measuring neurotoxicity in C. elegans, we showed that abnormal displacements and body postures in cat-2 mutants, which have the dopamine synthesis pathway disrupted, can be rescued by adding dopamine. Then, we used such a system to demonstrate that dopamine treatment protects from the dose-dependent neurotoxicity caused by cisplatin.

cell biology↗