Brain Injury In Rats Research Articles

Neuroprotective Effects of Ethanol Extract Polyscias guilfoylei (EEPG) Against Glutamate Induced Neurotoxicity in HT22 Cells

Oxidative stress induced by glutamate is a significant contributor to neuronal cell damage and can lead to neurodegenerative diseases such as Alzheimer’s, Huntington’s, and ischemic brain injury. At the cellular level, oxidative stress increases Ca2+ ion influx and reactive oxygen species (ROS), which activate the MAPK signaling pathway. Additionally, the generation of ROS causes mitochondrial dysfunction, triggering apoptosis by promoting the translocation of AIF to the nucleus from the mitochondria. The neuroprotective potential of Polyscias guilfoylei has not yet been reported. Therefore, in this study, the ethanol extract of Polyscias guilfoylei (EEPG) was examined for its protective effect against oxidative cell damage caused by glutamate in neuronal cells. EEPG treatment increased the viability of HT22 cells exposed to high concentrations of glutamate. Cellular Ca2+ ion influx and ROS generation decreased with EEPG treatment in glutamate-treated HT22 cells. EEPG treatment inhibited MAPK activation and AIF nuclear translocation. In an in vivo study, EEPG attenuated brain cell death in an ischemic brain injury rat model. This study demonstrates the potential therapeutic effects of Polyscias guilfoylei in the treatment of ischemic brain injury.

Asiatic acid alleviates subarachnoid hemorrhage-induced brain injury in rats by inhibiting ferroptosis of neurons via targeting acyl-coenzyme a oxidase 1

The occurrence of subarachnoid hemorrhage (SAH) can lead to brain injury, which is a fatal condition with limited effective clinical intervention strategies. The naturally occurring component Asiatic acid (AA), found in the tropical plant Centella asiatica, has been reported to possess neuroprotective properties. The objective of this study was to evaluate the neuroprotective effect of AA following SAH and investigate its potential mechanisms. The SAH model was established in male Sprague-Dawley (SD) rats through intravascular perforation, following a standardized protocol. The administration of AA was performed via gavage following SAH. A lentiviral vector was constructed and utilized for the knockdown of Acyl Coenzyme A Oxidase 1 (ACOX1) Firstly, AA treatment effectively improves brain neurological deficit, neuronal damage, and iron deposition induced by SAH. Furthermore, it has been demonstrated that AA directly interacts with ACOX1, which exhibits decreased expression in neurons following SAH. Additionally, our study reveals AA can reverse SAH-induced reduction in ACOX1 expression, concurrently ameliorating neuronal ferroptosis. This improvement is evidenced by reduced lipid peroxidation, including mitigated GSH depletion, decreased MDA production, and increased GPX4 content and activity. Also, AA enhances mitochondrial constriction while alleviating cristae disruption induced by SAH, providing crucial insights into its neuroprotective effects against neuronal ferroptosis in SAH. Moreover, when ACOX1 is knocked down, the neuroprotective effects of AA are weakened. Collectively, this study elucidated the neuroprotective effect of AA by inhibiting neuronal cell ferroptosis through targeting ACOX1. These findings suggest that AA holds promise as a potential therapeutic candidate for ameliorating SAH-induced brain injury.

Effect of Sertraline and Vortioxetine on Stress-Induced Brain Injury in Rats: Biochemical and Histopathological Evaluations

Objectives Our aim was to evaluate the comparative effects of sertraline and vortioxetine against stress-induced brain injury in rats. Methods The rats were assigned to a nonstress group (NSG), stress-treated control (StC), sertraline + stress (SSt), and vortioxetine + stress (VSt) groups. Sertraline and vortioxetine (10 mg/kg) were given orally by gavage to the SSt and VSt groups. One hour later, all animals (except NSG) underwent forced immobilization to establish a stress model (2 hours). The drugs were given once a day for 30 days. The animals were killed with ketamine 150 mg/kg, and tissues were removed from the cerebral cortex. One-way analysis of variance and Fisher post hoc least significant difference were conducted for the analysis. Results The malondialdehyde (nmol/mL) level was 2.58 ± 0.48 in the NSG, 8.09 ± 0.57 in the StC, 3.84 ± 0.53 in the SSt, and 2.84 ± 0.20 in the VSt group (P < 0.0002). The total glutathione (mmol/g) was 7.15 ± 0.59 in the NSG, 2.41 ± 0.43 in the StC, 4.58 ± 0.26 in the SSt, and 5.98 ± 0.13 in the VSt (P < 0.0002). The total oxidant status (mmol H2O2Eq/L) level was 3.56 ± 0.20 in the NSG, 9.99 ± 0.74 in the StC, 4.97 ± 0.39 in the SSt, and 3.81 ± 0.31 in the VSt (P < 0.0002). The total antioxidant status (mmolTroloxEq/L) level was 8.65 ± 0.37 in the NSG, 3.04 ± 0.22 in the StC, 6.29 ± 0.34 in the SSt, and 7.61 ± 0.40 in the VSt (P < 0.0002). Sertraline reduced pericellular edema in astrocytes and oligodendrocytes and decreased perivascular edema, dilatation, and congestion of blood vessels, whereas these were not seen with vortioxetine. Conclusions Compared with sertraline, vortioxetine is a neuroprotective antidepressant with higher antioxidant activity and can more effectively prevent stress-induced brain tissue injury.

The effects of Cordyceps polysaccharides on ischemic brain injury in rats via intervening with IL-23/IL-17 axis and the intestinal barrier

Cordyceps polysaccharide (CSP) has been shown to exhibit anti-inflammatory and antioxidant effects, with potential applications in ischemic stroke. This work is to explore the interventional potential of CSP in MCAO rats and the effects on the intestinal and cerebral IL-23/IL-17 axis. We conducted pharmacological experiments and mechanism exploration in MCAO rats. Our research showed that CSP improved the neurological function and cerebral pathological morphology, reduced cerebral infarction volume and water content in MCAO rats. We also found that CSP significantly decreased the IL-β, TNF-α and IL-6 in the ischemic brain and enhanced the ability of MCAO rats to resist oxidative stress. Additionally, CSP improved intestinal barrier, inhibited the activation of the TLR4/Myd88/NF-κβ signaling pathway and IL-23/IL-17 axis. The study results demonstrated the effectiveness of CSP in interfering with MCAO rats. The mechanism appears to be related to protecting the intestinal barrier and inhibiting the IL-23/IL-17 axis.

Unraveling Neurotoxicity Discrepancies: Comparative In vitro and In vivo Analysis of Colistin and Polymyxin B and the Underlying Mechanisms.

Polymyxins, including colistin and polymyxin B, are the final resort against Gram-negative bacterial infections. However, its clinical application is restricted due to concerns related to neurotoxicity. Despite the similar antibacterial spectrum and mode of action shared between colistin and polymyxin B, there is still a lack of definitive evidence to support the idea that their neurotoxicity profiles are identical. To comprehensively compare the neurotoxicity between colistin and polymyxin B both in vivo and in vitro and establish a theoretical foundation to guide the rational use of polymyxins within clinical settings. in vitro experiments simulated nerve damage by exposing N2a and RSC96 cells to colistin and polymyxin B. The evaluation of nerve injury included assessments of cell viability and apoptosis. To discern the variance in the mechanisms of nerve injury between colistin and polymyxin B, oxidative stress levels were examined, such as SOD, CAT, GSH, and malondialdehyde (MDA). In in vivo experiments, a rat nerve injury model was created by intraventricular injections of colistin and polymyxin B, respectively. The impact of these drugs on brain injury in rats, particularly within the hippocampus and medulla oblongata, was measured using HE and Nissl staining. The potential influence of polymyxins on the ferroptosis pathway was evaluated by assessing LPO and Fe2+ levels and the degree of mitochondrial impairment. At equivalent doses, colistin demonstrated a reduced level of neurotoxicity compared to polymyxin B, both in vitro and in vivo. in vitro experiments revealed greater cell viability and a lower apoptosis rate after colistin treatment than after polymyxin B treatment. This variance in outcomes could be attributed to the comparatively lower levels of oxidative stress associated with colistin administration.In a rat model, nerve injury resulted in observable damage to both the hippocampus and the medulla oblongata. A comprehensive assessment of the extent of damage in the CA1 to CA4 regions of the hippocampus, and the solitary tract nucleus of the medulla oblongata underscored that the neurotoxic effects of colistin remained milder compared to those elicited by polymyxin B. Even when evaluated at equivalent multiples of clinically recommended doses, colistin exhibited lower neurotoxicity in vivo than polymyxin B. For the first time, this study demonstrated the role of ferroptosis in polymyxin B-induced nerve damage. The activation levels observed within the ferroptosis pathway due to polymyxin B exceeded those triggered by colistin. Colistin exhibited a marked reduction in neurotoxicity compared to polymyxin B, evident in both the equivalent and clinically recommended doses. These findings suggest that, from the perspective of neurotoxicity, colistin presents a more favorable option for clinical use.

Optimal Parameters of Magnetic Field Action and their Influence on Some Index Improvement in Traumatic Brain Injury Rat Modell

Optimal Parameters of Magnetic Field Action and their Influence on Some Index Improvement in Traumatic Brain Injury Rat Modell

Long-term hypothermia amplified neuroprotection by antagonizing intracranial pressure rebound after severe traumatic brain injury in rats.

Long-term hypothermia has been reported to prevent intracranial pressure (ICP) rebound in clinical patients, but the duration for hypothermia and the corresponding ICP data are not available. This study investigated the optimal duration of long-term hypothermia in traumatic brain injury (TBI) rats, and observed the effect on ICP and neurological function. In this study, we established a rat severe TBI model with electronic Controlled Cortical Injury device, and implemented hypothermia (33 °C) for different durations. The motor function of the rats in each group was evaluated by beam walking test and inclined-grid climbing test, brain water content was calculated by the wet-dry weight method, Evan's blue staining was used to measure the blood-brain barrier (BBB) permeability, the change of hippocampal neurons was observed by Nissl staining, the expressions of BrdU, NeuN, and CD86 positive cells were detected by immunofluorescence staining, and the expressions of Bcl-2, Bax, iNOS, IL-10, and Arg-1 were detected by Western blot. We found that therapeutic hypothermia improved neurological recovery after TBI with declining ICP, reducing brain edema, decreasing BBB permeability, promoting neurogenesis, inhibiting apoptosis, and regulating inflammation. Moreover, 48 h hypothermia amplified the neuroprotective effect after injury on the basis of 4 or 24 h hypothermic treatment. Both 4 and 24 h hypothermia led to ICP rebound during or after rewarming, whereas 48 h hypothermia completely abolished ICP rebound. Our study suggests that long-term hypothermia amplifies neuroprotection after TBI by antagonizing ICP rebound.

Sex-dependent temporal changes in astrocyte-vessel interactions following diffuse traumatic brain injury in rats.

Traumatic brain injury (TBI) is associated with diffuse axonal injury (DAI), a primary pathology linked to progressive neurodegeneration and neuroinflammation, including chronic astrogliosis, which influences long-term post-TBI recovery and morbidity. Sex-based differences in blood-brain barrier (BBB) permeability increases the risk of accelerated brain aging and early-onset neurodegeneration. However, few studies have evaluated chronic time course of astrocytic responses around cerebrovascular in the context of aging after TBI and sex dependence. We observed increased glial fibrillary acidic protein (GFAP)-labeled accessory processes branching near and connecting with GFAP-ensheathed cortical vessels, suggesting a critical nuance in astrocyte-vessel interactions after TBI. To quantify this observation, male and female Sprague Dawley rats (∼3months old, n = 5-6/group) underwent either sham surgery or midline fluid percussion injury. Using immunohistochemical analysis, we quantified GFAP-labeled astrocyte primary and accessory processes that contacted GFAP-ensheathed vessels in the somatosensory barrel cortex at 7, 56, and 168days post-injury (DPI). TBI significantly increased GFAP-positive primary processes at 7 DPI (P < 0.01) in both sexes. At 56 DPI, these vessel-process interactions remained significantly increased exclusively in males (P < 0.05). At 168 DPI, both sexes showed a significant reduction in vessel-process interactions compared to 7 DPI (P < 0.05); however, a modest but significant injury effect reemerged in females (P < 0.05). A similar sex-dependent pattern in the number of accessory processes provides novel evidence of long-term temporal changes in astrocyte-vessel interactions. TBI-induced changes in astrocyte-vessel interactions may indicate chronic BBB vulnerability and processes responsible for early onset vascular and neurodegenerative pathology.

Electroacupuncture Promotes the Generation of Intestinal Treg Cells After Ischemic Stroke by Foxp3 Acetylation Regulation.

Electroacupuncture (EA) has been shown to ameliorate brain injury and protect against intestinal injury after ischemic stroke. These protective effects are closely associated with the enhancement of regulatory T (Treg) cell numbers and function in the intestine, as well as the inhibition of intestinal γδ T cell production and their migration to the brain. This study aimed to elucidate the potential mechanism by which EA regulates intestinal Treg cell differentiation after stroke. Sprague-Dawley rats were divided into three groups: the sham group, the middle cerebral artery occlusion (MCAO) group, and the MCAO plus EA (MEA) group. The MCAO model was generated by occluding the middle cerebral artery. EA was applied to Baihui (GV20) acupoint once daily. Samples were collected 3days after reperfusion. Our results showed that EA reduced the inflammatory response in the brain and intestine after ischemic stroke. EA treatment increased the percentage of Treg cells in the small intestine of rats. EA increased the levels of SCFAs, while also inhibiting histone deacetylase activity (HDAC). Additionally, acetylated Foxp3 protein in the small intestine was increased after EA treatment. These results suggest that EA at GV20 alleviates brain and intestinal inflammatory injury in stroke rats, potentially through the enhancement of SCFA-mediated Foxp3 acetylation in Treg cells.

Prophylactic and Therapeutic Effects of Progesterone on the Preterm Brain Injury Rat Model.

Neurodevelopmental disorders are chronic conditions affecting behavior, cognition, and social function, often arising from early brain development disruptions. Preterm infants are particularly vulnerable to brain injuries, such as periventricular leukomalacia, which can lead to long-term disabilities. This study aimed to investigate the neuroprotective effect of progesterone in reducing the severity of a preterm brain injury in rat model. A preterm brain injury rat model was established using lipopolysaccharide to induce brain injury. The neuroprotective effects of progesterone were evaluated through histological assessments comparing treated and untreated groups. The study also aimed to assess the efficacy of progesterone in controlling brain injury severity. The findings suggest that progesterone exhibits neuroprotective properties, with a significant difference in the severity of brain injury. The histological evaluations suggest that progesterone may reduce inflammation and promote neuronal survival in preterm brain injury. The administration of progesterone shows promising results as a therapeutic strategy for preventing and treating brain injuries in preterm rat pups. Further research is needed to explore the underlying mechanisms and potential clinical applications of the hormone.

Effect of ethanol extract of nigella sativa L seeds and propofol on BDNF protein level as neuroplasticity and neuroprotection of traumatic brain injury in rats

Background Traumatic brain injury (TBI) is a change in brain function or evidence of brain pathology caused by external mechanical forces. Brain Derived Neurotrophic Factor (BDNF) is a neurotropin that functions as a neuron protective. Nigella sativa L is reported to have an antioxidant effect, administration of Nigella Sativa L to rats treated with ischemia-reperfusion brain injury. Propofol is an anesthetic agent frequently used intravenously in the management of TBI. The effect of propofol on brain tissue after TBI may be neuroprotective. We aimed to compare the potential of Nigella sativa L and propofol as neuroplasticity and neuroprotection in rats with TBI. Methods This was a laboratory experimental animal model with the post-test only control group design, namely measuring the effect of treatment by comparing the five groups of rats consisting of 30 rats. BDNF levels in rat brain tissue were collected at day 7 of treatment and measured by ELISA. Results The average BDNF protein levels per group, namely G1 (221,243 pg/mL), G2 (172,139 pg/mL), G3 (255,483 pg/mL), G4 (227,089 pg/mL), and G5 (272,603 pg/mL) respectively. Based on the ANOVA statistic, p-value = 0.032 (there was a significant difference between groups), with the Levene Test (0.077) or having variance between the same groups, sequentially the difference in average BDNF protein levels of the five groups is G5&gt;G3&gt;G4&gt;G1&gt;G2, meaning that the combination of Nigella sativa and propofol has more potential to increase BDNF protein levels than Nigella sativa, and Nigella sativa has more potential than propofol. Conclusion We concluded that both nigella sativa and propofol have the potential to increase BDNF protein levels. Nigella Sativa L had a better effect than propofol in repairing damaged neuron cells (neuroplasticity) and increasing BDNF protein levels (neuroprotection) for 7 days of administration in rat traumatic brain injury.

TREM1 promotes neuroinflammation after traumatic brain injury in rats: Possible involvement of ERK/cPLA2 signalling pathway

The neuroinflammatory response promotes secondary brain injury after traumatic brain injury (TBI). Triggering receptor expressed on myeloid cells 1 (TREM1) is a key regulator of inflammation. However, the role of TREM1 in TBI is poorly studied. The purpose of this study was to investigate the role of TREM1 in TBI and the possible underlying mechanism. We found that the protein expression of TREM1 significantly increased after TBI in rats, and the TREM1 protein localized to microglia. Inhibition of the TREM1 protein with LP17 significantly blocked ERK phosphorylation and reduced cytoplasmic phospholipase A2 (cPLA2) protein expression and phosphorylation. In addition, LP17-mediated TREM1 inhibition significantly reduced the protein expression of iNOS and increased the protein expression of Arg1 . Moreover, after TREM1 was inhibited, the secretion of the proinflammatory factors TNF-α and IL-1β was significantly reduced, while the secretion of the anti-inflammatory factors IL-4 and IL-10 was significantly increased. Additionally, inhibition of TREM1 by LP17 significantly reduced neuronal apoptosis and ameliorated nerve dysfunction in TBI model rats. In conclusion, our findings suggest that TREM1 enhances neuroinflammation and promotes neuronal apoptosis after TBI, and these effects may be partly mediated via the ERK/cPLA2 signalling pathway.

Genistein-3′-sodium sulfonate enhances neurological function in neonatal rats with hypoxia-ischemia during the recovery period

Hypoxic-ischemic (HI) can cause neonatal brain damage leading to disability. Patients with HI experience long-term neurological issues impacting quality of life. Limited clinical treatments are available despite extensive research on HI's molecular mechanisms. Genistein-3′-sodium sulfonate (GSS), a phytoestrogen, has been found to improve acute brain injury in neonatal rats caused by hypoxic-ischemia, but its potential for chronic stage neurological recovery in HI is unknown. HI neonatal rats were treated with 1 mg/kg GSS once a day for 21 days. Then, a series of behavioral experiments was performed to evaluate the learning, memory, cognition, anxiety level and depression-like behaviors of the rats. GSS treatment reduced neuronal loss, enhanced learning, memory and cognitive function while also alleviated anxiety and depression-like behaviors in HI rats during the recovery period. These findings indicated that GSS exerted enhance neurological function in HI rats during the chronic stage, prompting further research on how it works to potentially develop new therapies.

Effect of Mucuna pruriens seed extract on depression-like behavior derived from mild traumatic brain injury in rats.

Traumatic brain injury (TBI) is a severe health problem for which there is no specific treatment, leading to neurological or neuropsychological consequences. One of the most described disorders, even after mild TBI (mTBI), is depression, related to mechanisms involving reactive oxygen species (ROS). The Mucuna pruriens (M. pruriens) plant has various antioxidant, neuroprotective, and anti-inflammatory properties. There is insufficient evidence of M. pruriens use for the treatment of neurobehavioral and depressive impairments induced by TBI and of the mechanisms underlying this effect, so we aimed to evaluate the ability of shortterm administration of M. pruriens extract to prevent neurobehavioral impairment and depression-like behaviors in a murine model of mTBI as well as evaluate the role of oxidative stress. Male Wistar rats underwent mTBI or sham surgery. Immediately after, they were treated with vehicle or M. pruriens extract (50 mg/kg ip/day for five days). We evaluated neurobehavioral recovery using the Neurobehavioral Severity Scale-Revised (NSS-R) and the immobility time in the forced swimming test 3, 7, 15, 30, and 60 days after mTBI. In addition, lipid peroxidation (LP) and GSH concentrations were determined in some brain areas (motor cortex, striatum, midbrain, and nucleus accumbens). M. pruriens extract did not decrease neurobehavioral impairment caused by mTBI. Nevertheless, it prevented depression-like behaviors starting three days after mTBI, reduced LP, and increased GSH in some brain areas. Conclusions: M. pruriens may prevent depression-like behaviors and reduce oxidative stress by decreasing LP and increasing concentrations of antioxidant compounds.

Physical exercise as a cognitive rehabilitation treatment after traumatic brain injury: Intensity- and sex-dependent effects

We investigated the effects of forced physical exercise (PE) intensity on cognitive dysfunction and histological changes associated with traumatic brain injury (TBI), in both male and female rats. Controlled cortical impact (CCI) produced similar short- and long-term memory deficits in both sexes, and these deficits were associated with reduced volume and neuronal loss in the hippocampus, but not with changes in neurogenesis. We found sex differences in the effects of intensity of forced PE on cognitive recovery: all PE intensities tested improved short-term memory in both sexes, but to a greater extent in females, while long-term memory benefits were intensity- and sex-dependent. Males benefited most from low-intensity PE, while females showed optimal results at moderate intensity. These optimal PE intensities increased the neurogenesis in both sexes. A neuroprotective effect of low-intensity PE was evident in males, but no effect was observed in females. These findings suggest an intensity- and sex-specific effect of PE post-TBI, emphasizing the need for tailored PE protocols based on sex to enhance therapeutic outcomes.

Scopolamine-induced brain injury and lipid peroxidation in Wistar rats ameliorated by garlic oil supplementation

Scopolamine-induced brain injury and lipid peroxidation in Wistar rats ameliorated by garlic oil supplementation

Anxiety-like Characteristics, Forepaw Thermal Sensitivity Changes and Glial Alterations 1 Month After Repetitive Blast Traumatic Brain Injury in Male Rats.

Many military service members are victims of repetitive blast traumatic brain injuries (rbTBI) and endure diverse altered psychological and behavioural conditions during their lifetime. Some of these conditions include anxiety, post-traumatic stress and pain. Thus, this study attempts to fill the knowledge gap on enduring behavioural and neuroinflammatory marker alterations 1 month after rbTBI. Although previous rbTBI animal studies have shown behavioural and histopathological changes either a few days (acute) or many months (chronic) after trauma, knowledge related to post-traumatic changes during the intermediate timeframe, i.e. a month after rbTBI is less clear or unavailable. Sprague-Dawley rats (male; n = 12) were assigned to either rbTBI or sham conditions. Animals assigned to the rbTBI group were subjected to 1 blast exposure per day for three consecutive days, while animals in the sham group were exposed to identical experimental conditions sans blast exposure. All animals were tested for anxiety at baseline. 30 days post-injury, animals were tested again for anxiety and paw thermal sensitivity, followed by brain harvest for immunohistochemical analyses. Animals exposed to rbTBI showed signs of anxiety-like behaviour on parameters of elevated plus-maze and behavioural signs of pain indicated by reduced thermal withdrawal latency of the forepaw. Histologically, brain sections from animals exposed to rbTBI showed a significantly increased number of microglial/macrophage and astrocytic counts in the medial prefrontal cortex. Data from this initial preclinical study support the prevalence of putative anxiety-like behaviour, enhancement in forepaw thermal sensitivity and increase in the number of glial cells even 1 month after rbTBI. These findings have potential implications in the treatment evaluation of blast-exposed military and civilian populations and emphasise the need for devising protective measures for people susceptible to single or repeated exposures. A greater further understanding of rbTBI-related chronic concurrent behavioural and neuropathological sequela is warranted.

Utility of melatonin on brain injury, synaptic transmission, and energy metabolism in rats with sepsis.

Melatonin is a powerful endogenous antioxidant hormone. Its healing effects on energy balance and neuronal damage associated with oxidative metabolism disorders have been reported in pathologic conditions. We aimed to determinate the utility of melatonin on neuronal damage, synaptic transmission, and energy balance in the brain tissue of rats with sepsis induced with LPS. Rats was divided into four groups such as control, LPS (20mg/kg i.p.), melatonin (10mg/kg i.p. × 3), and LPS + Melatonin (LPS + Mel). After 6h from the first injection, rats were decapitated, and also tissue and serum samples were taken. Lipid peroxidation and neuron-specific enolase (NSE) levels were determined from the serum in all group. High energy compounds, creatine, and creatine phosphate are measured by HPLC methods from the homogenized tissue. Counts of living neurons are marked with NeuN (neuronal nuclei), degenerated neurons are marked with S100-ß and synaptic vesicles transmission is analyzed with synaptophysin antibodies immunoreactivities. One-way ANOVA and post hoc Tukey tests were used to statistical analysis. In LPS group, AMP, ATP, creatine, and creatine phosphate levels were significantly decreased (p < 0.05), and also ADP levels were significantly increased compared with the other groups (p < 0.01). Living neurons counts were significantly decreased in LPS (p < 0.01), melatonin, and LPS + Melatonin (p < 0.05) groups compared with control. Degenerated neurons counts were increased in LPS group compared with control (p < 0.01) and also decreased in both of melatonin and LPS + Melatonin groups (p < 0.01). Synaptophysin immunoreactivity was decreased in LPS group compared with the other groups (p < 0.05). We observed that melatonin administration prevents neuronal damage, regulates energy metabolism, and protects synaptic vesicle proteins from sepsis-induced reduction.

Melatonin alleviates brain injury in copper-laden rats: Underlying benefits for Wilson’s disease

Copper serves as an indispensable cofactor for all living organisms, and its excessive accumulation has been associated with a variety of diseases. Wilson’s disease (WD) serves as an illustrative example of copper toxicity in humans, frequently presenting with liver and/or neuropsychiatric symptoms. The current therapeutic drugs, penicillamine (PA) and zinc gluconate (ZnG), have constraints, and research on their combination efficacy remains insufficient. It has been reported that melatonin (MLT) plays a vital role in binding to transition metals and exhibits strong antioxidant capacity. To investigate the therapeutic efficacy of MLT and combined treatment, rats were randomly divided into the following seven groups: the control (Con) group, copper-laden model rat (Mod) group, PA-treated group, ZnG-treated group, MLT- treated group, PA-ZnG-treated group, and PA-MLT-treated group. Then potential mechanisms and targets were investigated using a combination of metabolomics and network pharmacology and verified by molecular docking and qPCR. The findings revealed that MLT and the combination significantly improved behavior, pathology and copper levels in copper-laden rats. The results of the metabolomics study showed that profoundly altered metabolites were identified, and alanine, aspartate and glutamate metabolism, pyruvate metabolism, citrate cycle (TCA cycle), and glycolysis/gluconeogenesis were explored. In addition, molecular docking showed that MLT had high binding affinity with key targets, and qPCR results revealed that MLT could reverse the mRNA expression of targets GOT2 and PKM2. It was concluded that MLT effectively improves brain injury in copper-laden rats, and this effect was linked with the altered features of the metabolite profiles.

The mGluR5-mediated Arc activation protects against experimental traumatic brain injury in rats.

Traumatic brain injury (TBI) is a complex pathophysiological process, and increasing attention has been paid to the important role of post-synaptic density (PSD) proteins, such as glutamate receptors. Our previous study showed that a PSD protein Arc/Arg3.1 (Arc) regulates endoplasmic reticulum (ER) stress and neuronal necroptosis in traumatic injury invitro. In this study, we investigated the expression, regulation and biological function of Arc in both invivo and invitro experimental TBI models. Traumatic neuronal injury (TNI) induced a temporal upregulation of Arc in cortical neurons, while TBI resulted in sustained increase in Arc expression up to 24 h in rats. The increased expression of Arc was mediated by the activity of metabotropic glutamate receptor 5 (mGluR5), but not dependent on the intracellular calcium (Ca2+) release. By using inhibitors and antagonists, we found that TNI regulates Arc expression via Gq protein and protein turnover. In addition, overexpression of Arc protects against TBI-induced neuronal injury and motor dysfunction both invivo and invitro, whereas the long-term cognitive function was not altered. To determine the role of Arc in mGluR5-induced protection, lentivirus-mediated short hairpin RNA (shRNA) transfection was performed to knockdown Arc expression. The mGluR5 agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG)-induced protection against TBI was partially prevented by Arc knockdown. Furthermore, the CHPG-induced attenuation of Ca2+ influx after TNI was dependent on Arc activation and followed regulation of AMPAR subunits. The results of Co-IP and Ca2+ imaging showed that the Arc-Homer1 interaction contributes to the CHPG-induced regulation of intracellular Ca2+ release. In summary, the present data indicate that the mGluR5-mediated Arc activation is a protective mechanism that attenuates neurotoxicity following TBI through the regulation of intracellular Ca2+ hemostasis. The AMPAR-associated Ca2+ influx and ER Ca2+ release induced by Homer1-IP3R pathway might be involved in this protection.