Edaravone Alleviates Traumatic Brain Injury by Inhibition of Ferroptosis via FSP1 Pathway.

Traumatic brain injury (TBI) is a highly severe form of trauma with complex series of reactions in brain tissue which ultimately results in neuronal damage. Previous studies proved that neuronal ferroptosis, which was induced by intracranial haemorrhage and other reasons, was one of the most primary causes of neuronal damage following TBI. However, the association between neuronal mechanical injury and ferroptosis in TBI and relevant treatments remain unclear. In the present study, we first demonstrated the occurrence of neuronal ferroptosis in the early stage of TBI and preliminarily elucidated that edaravone (EDA), a cerebroprotective agent that eliminates oxygen radicals, was able to inhibit ferroptosis induced by TBI. A cell scratching model was established in PC12 cells, and it was confirmed that mechanical injury induced ferroptosis in neurons at the early stage of TBI. Ferroptosis suppressor protein 1 (FSP1) plays a significant role in inhibiting ferroptosis, and we found that iFSP, a ferroptosis agonist which is capable to inhibit FSP1 pathway, attenuated the anti-ferroptosis effect of EDA. In conclusion, our results suggested that EDA inhibited neuronal ferroptosis induced by mechanical injury in the early phase of TBI by activating FSP1 pathway, which could provide evidence for future research on prevention and treatment of TBI.

The application of iliac fascia space block combined with esketamine intravenous general anesthesia in PFNA surgery of the elderly: A prospective, single-center, controlled trial.

To observe the effect of iliac fascia space block combined with esketamine intravenous general anesthesia in proximal femoral nail antirotation (PFNA) of the elderly. Eighty elderly patients who underwent PFNA were randomly divided into experimental group and control group. In the experimental group, iliac fascial block combined with esketamine and propofol intravenous general anesthesia was used to keep spontaneous breathing. The control group used iliac fascia block combined with remifentanil and propofol intravenous general anesthesia to maintain spontaneous breathing. Record important indexes such as heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SpO2), visual analogue score (VAS) scores, etc. at different moment during the operation. Trial data showed that there were significant differences in HR, MAP, and SpO2 between the two groups at the beginning of operation, and there was no significant difference in VAS scores between the two groups at each moment after surgery, and there were significant differences in the number of vasopressor applications, length of hospital stay, and QoR-15 scores between the two groups, and there were significant differences in the incidence of total adverse reactions and the incidence of hypotension. The trial indicated that patients in the experimental group have more stable hemodynamics and lower stress response, which is conducive to rapid recovery after surgery.

Esketamine is neuroprotective against traumatic brain injury through its modulation of autophagy and oxidative stress via AMPK/mTOR-dependent TFEB nuclear translocation.

Recent clinical studies highlight the neuroprotective effects of esketamine, but its benefits following traumatic brain injury (TBI) have not been defined. Here, we investigated the effects of esketamine following TBI and its associated neuroprotection mechanisms. In our study, controlled cortical impact injury on mice was utilized to induce the TBI model in vivo. TBI mice were randomized to receive vehicle or esketamine at 2 h post-injury for 7 consecutive days. Neurological deficits and brain water content in mice were detected, respectively. Cortical tissues surrounding focal trauma were obtained for Nissl staining, immunofluorescence, immunohistochemistry, and ELISA assay. In vitro, esketamine were added in culture medium after cortical neuronal cells induced by H2O2 (100µM). After exposed for 12h, neuronal cells were obtained for western blotting, immunofluorescence, ELISA and CO-IP assay. Following administration of 2-8 mg/kg esketamine, we observed that 8 mg/kg esketamine produced no additional recovery of neurological function and ability to alleviate brain edema in TBI mice model, so 4 mg/kg esketamine was selected for subsequent experiments. Additionally, esketamine can effectively reduce TBI-induced oxidative stress, the number of damaged neurons, and the number of TUNEL-positive cells in the cortex of TBI models. Meanwhile, the levels of Beclin 1, LC3 II, and the number of LC3-positive cells in injured cortex were also increased following esketamine exposure. Western blotting and immunofluorescence assays showed that esketamine accelerated the nuclear translocation of TFEB, increased the p-AMPKα level and decreased the p-mTOR level. Similar results including nuclear translocation of TFEB, the increases of autophagy-related markers, and influences of AMPK/mTOR pathway were observed in H2O2-induced cortical neuronal cells; however, BML-275 (AMPK inhibitor) can reverse these effects of esketamine. Furthermore, TFEB silencing not only decreased the Nrf2 level in H2O2-induced cortical neuronal cells, but also alleviated the oxidative stress. Importantly, CO-IP confirmed the interaction between TFEB and Nrf2 in cortical neuronal cells. These findings suggested that esketamine exerts the neuroprotective effects of esketamine in TBI mice model via enhancing autophagy and alleviating oxidative stress; its mechanism involves AMPK/mTOR-dependent TFEB nuclear translocation-induced autophagy and TFEB/Nrf2-induced antioxidant system.

Cerebrolysin alleviates early brain injury after traumatic brain injury by inhibiting neuroinflammation and apoptosis via TLR signaling pathway.

PURPOSE: Traumatic brain injury (TBI) is a major cause of death and disability. Cerebrolysin (CBL) has been reported to be anti-inflammatory by reducing reactive oxygen species (ROS) production. However, the neuroprotection of CBL in TBI and the potential mechanism are unclear. We aimed to investigate the neuroprotection and mechanisms of CBL in TBI. METHODS: The TBI model was established in strict accordance with the Feeney weight-drop model of focal injury. The neurological score, brain water content, neuroinflammatory cytokine levels, and neuronal damage were evaluated. The involvement of the early brain injury modulatory pathway was also investigated. RESULTS: Following TBI, the results showed that CBL administration increased neurological scores and decreased brain edema by alleviating blood­brain barrier (BBB) permeability, upregulating tight junction protein (ZO­1) levels, and decreasing the levels of the inflammatory cytokines tumor necrosis factor­α (TNF­α), interleukin­1ß (IL­1ß), IL­6, and NF­κB. The TUNEL assay showed that CBL decreased hippocampal neuronal apoptosis after TBI and decreased the protein expression levels of caspase­3 and Bax, increasing the levels of Bcl­2. The levels of Toll­like receptor 2 (TLR2) and TLR4 were significantly decreased after CBL treatment. In TBI patients, CBL can also decrease TNF­α, IL­1ß, IL­6, and NF­κB levels. This result indicates that CBL­mediated inhibition of neuroinflammation and apoptosis ameliorated neuronal death after TBI. The neuroprotective capacity of CBL is partly dependent on the TLR signaling pathway. CONCLUSIONS: Taken together, the results of this study indicate that CBL can improve neurological outcomes and reduce neuronal death against neuroinflammation and apoptosis via the TLR signaling pathway in mice.

Effects of dexmedetomidine on cognitive dysfunction and neuroinflammation via the HDAC2/HIF-1α/PFKFB3 axis in a murine model of postoperative cognitive dysfunction.

Inhibition of histone deacetylase (HDAC) may be a useful approach in the treatment of disorders characterized by cognitive dysfunction. Dexmedetomidine (DEX), an α2-adrenoceptor (α2-AR) agonist, has demonstrated neuroprotective effects. Here, we attempted to investigate the protective effects of DEX on postoperative cognitive dysfunction (POCD) involving HDAC2. Male C57BL/6 mice were selected to develop a POCD model, where HDAC2, HIF-1α, and PFKFB3 expression was quantified. DEX was administered before POCD modeling. Then the cognitive function of POCD mice was evaluated with the open field and Y-maze tests. Meanwhile, lipopolysaccharide (LPS) was employed to induce BV-2 microglial cells to simulate the inflammatory response. The contents of TNF-α, IL-6, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA) in mouse serum and BV-2 cell supernatant. Abundant expression of HDAC2, HIF-1α, and PFKFB3 was confirmed in POCD mice (p < 0.05). Cognitive dysfunction in POCD mice could be alleviated following pharmacological inhibition of HDAC2 by FK228 (p < 0.05). Mechanistically, HDAC2 upregulated HIF-1α and PFKFB3 and promoted the secretion of inflammatory factors in LPS-exposed BV-2 cells (p < 0.05). DEX attenuated neuroinflammation and the resulting cognitive dysfunction by decreasing HDAC2 expression and HIF-1α-dependent PFKFB3 upregulation in POCD mice (p < 0.05). In conclusion, DEX-regulated HDAC2 may play an inhibitory role in mice with POCD through regulation of the HIF-1α/PFKFB3 axis.

Cerebrolysin alleviates early brain injury after traumatic brain injury by inhibiting neuroinflammation and apoptosis via TLR signaling pathway

Purpose: Traumatic brain injury (TBI) is a major cause of death and disability. Cerebrolysin (CBL) has been reported to be anti-inflammatory by reducing reactive oxygen species (ROS) production. However, the neuroprotection of CBL in TBI and the potential mechanism are unclear. We aimed to investigate the neuroprotection and mechanisms of CBL in TBI. Methods: The TBI model was established in strict accordance with the Feeney weight-drop model of focal injury. The neurological score, brain water content, neuroinflammatory cytokine levels, and neuronal damage were evaluated. The involvement of the early brain injury modulatory pathway was also investigated. Results: Following TBI, the results showed that CBL administration increased neurological scores and decreased brain edema by alleviating blood­brain barrier (BBB) permeability, upregulating tight junction protein (ZO­1) levels, and decreasing the levels of the inflammatory cytokines tumor necrosis factor­α (TNF­α), interleukin­1ß (IL­1ß), IL­6, and NF­κB. The TUNEL assay showed that CBL decreased hippocampal neuronal apoptosis after TBI and decreased the protein expression levels of caspase­3 and Bax, increasing the levels of Bcl­2. The levels of Toll­like receptor 2 (TLR2) and TLR4 were significantly decreased after CBL treatment. In TBI patients, CBL can also decrease TNF­α, IL­1ß, IL­6, and NF­κB levels. This result indicates that CBL­mediated inhibition of neuroinflammation and apoptosis ameliorated neuronal death after TBI. The neuroprotective capacity of CBL is partly dependent on the TLR signaling pathway. Conclusions: Taken together, the results of this study indicate that CBL can improve neurological outcomes and reduce neuronal death against neuroinflammation and apoptosis via the TLR signaling pathway in mice.

Erratum to "Ulinastatin alleviates traumatic brain injury by reducing endothelin-1".

[This corrects the article DOI: 10.1515/tnsci-2021-0001.].

Ulinastatin alleviates traumatic brain injury by reducing endothelin-1.

BACKGROUND: Brain edema is one of the major causes of fatality and disability associated with injury and neurosurgical procedures. The goal of this study was to evaluate the effect of ulinastatin (UTI), a protease inhibitor, on astrocytes in a rat model of traumatic brain injury (TBI). METHODOLOGY: A rat model of TBI was established. Animals were randomly divided into 2 groups - one group was treated with normal saline and the second group was treated with UTI (50,000 U/kg). The brain water content and permeability of the blood-brain barrier were assessed in the two groups along with a sham group (no TBI). Expression of the glial fibrillary acidic protein, endthelin-1 (ET-1), vascular endothelial growth factor (VEGF), and matrix metalloproteinase 9 (MMP-9) were measured by immunohistochemistry and western blot. Effect of UTI on ERK and PI3K/AKT signaling pathways was measured by western blot. RESULTS: UTI significantly decreased the brain water content and extravasation of the Evans blue dye. This attenuation was associated with decreased activation of the astrocytes and ET-1. UTI treatment decreased ERK and Akt activation and inhibited the expression of pro-inflammatory VEGF and MMP-9. CONCLUSION: UTI can alleviate brain edema resulting from TBI by inhibiting astrocyte activation and ET-1 production.

Sevoflurane exerts protective effects on liver ischemia/reperfusion injury by regulating NFKB3 expression via miR-9-5p.

Hepatic ischemia/reperfusion (IR) injury is a critical contraindication of hepatobiliary surgery and results in severe liver damage. It is imperative to identify underlying pathophysiological mechanisms. In the current study, a rat model of liver IR was established to explore the mechanisms of sevoflurane during surgical intervention on IR. The detection of cytokines was performed using ELISA and reverse transcription-quantitative polymerase chain reaction and western blot assays were used to detect mRNA and protein expression levels, respectively. The target protein of microRNA (miR)-9-5p was identified by in vitro luciferase reporter assay. Cell apoptosis was detected by Annexin-V/propidium iodide and TUNEL staining assays. The results demonstrated that sevoflurane exerted protective effect against liver IR. Sevoflurane administration ameliorated a cytokine storm by decreasing serum levels of interleukin (IL)-1 and -6 and tumor necrosis factor (TNF)-α, and improved liver function was determined. IR-induced damage was mediated by an increase in transcription factor p65 expression and activation of the nuclear factor (NF)-κB signaling pathway, which were suppressed by sevoflurane treatment. In situ analysis predicted that NFKB3, encoding for p65, may be targeted by miR-9-5p and the hypothesis was verified by in vitro reporter assays using wild type and mutant sequences of the NFKB3 3'-untranslated region. Furthermore, pretreatment of hepatic tissue with a miR-9-5p mimic inhibited IR-associated injury as suggested by the decrease in the Suzuki score and decreased serum levels of TNF-α, IL-1 and IL-6. The results indicated that sevoflurane protected the liver from IR injury by increasing miR-9-5p expression and miR-9-5p may be a potential treatment target in IR.

The antidepressant effects of rosiglitazone on rats with depression induced by neuropathic pain.

A growing number of studies reported that rosiglitazone (a PPARgamma agonist) could ameliorate the painful state and prevent stress-induced depression. However, whether rosiglitazone can prevent pain-induced depression is unclear. This study aimed to explore the antidepressant effects of rosiglitazone in L5 spinal nerve transection (SNT) induced neuropathic pain rats. In addition, AMPK inhibitor (Compound C) and autophagic antagonist (3-methyladenine, 3-MA) were applied to investigate the underlying therapeutic mechanisms. L5 SNT-induced neuropathic pain symptoms and depressive like-behaviors were detected by paw pressure threshold test (PPT), open-field test (OFT), forced swimming test (FST), tail suspension test (TST), sucrose preference test (SPT). Rosiglitazone could ameliorate L5 SNT-induced neuropathic pain symptoms and depressive like-behaviors and the effect could be reversed by Compound C or 3-MA. Compared with the sham group, the levels of BDNF, AMPK, Beclin-1 and LC3B in rats hippocampus significantly decreased in L5 SNT group. On the contrary, rosiglitazone administration significantly up-regulated the levels of AMPK, BDNF, Beclin-1 and LC3B in rats hippocampus. Compared with sham group, the levels of TNF-α, IL-1ß, superoxide dismutase (SOD) and malondialdehyde (MDA) in rat hippocampus significantly increased in L5 SNT group. Besides, rosiglitazone administration significantly decreased the levels of TNF-α, IL-1ß, SOD and MDA in hippocampus. Compared with rosiglitazone group, 3-MA administration, but not Compound C administration, significantly increased the levels of TNF-α, IL-1ß, SOD and MDA in hippocampus. In conclusion, rosiglitazone can counteract down-regulation of AMPK and BDNF induced by L5 SNT rats in hippocampus, and activate autophagic pathway. These effects may contribute to the antidepressant effect of rosiglitazone on the rats with depression induced by L5 SNT.

Developmental loss of parvalbumin-positive cells in the prefrontal cortex and psychiatric anxiety after intermittent hypoxia exposures in neonatal rats might be mediated by NADPH oxidase-2.

Sleep apnea is more frequently experienced in neonatal life. Here we investigated the causal contribution of NOX2-derived oxidative stress in the prefrontal cortex (PFC) to neurodevelopmental alterations and psychiatric anxiety in a neonatal rat model of sleep apnea. Neonatal postnatal day 5 (P5) rats were exposed to long-term intermittent hypoxia (LTIH) or room air (RA) for 10 days. In the PFC, we determined the impact (I) of LTIH exposures on NADPH oxidase-2 (NOX2) expression and oxidative stress (II) of pharmacological NOX2 inhibition on LTIH-induced neurodevelopmental alterations in the P14 and P49 rats. Endpoints were NOX2-derived oxidative stress, parvalbumin (PV)-positive cells (PV-cells) and psychiatric anxiety. The results showed neonatal LTIH exposures increased NOX2 expression in the PFC of P14 rats, which was accompanied with elevation of NOX activity. Neonatal LTIH exposures increased oxidative stress in cortical PV-cells characterized by elevation of 8-hydroxy-20-deoxyguanosine (8-OHDG) level and reduced PV immunoreactivity, PV-cell counts in the PFC of P14 and P49 rats. Neonatal LTIH exposures increased psychiatric anxiety levels in the P49 rats. Pretreatment of neonatal rats before each neonatal LTIH exposure with the antioxidant/NOX inhibitor apocynin prevented the reduced PV immunoreactivity, PV-cells loss in the PFC and development of anxiety-like behavior. Our data suggest that NOX2-derived oxidative stress might be involved in the developmental loss of PV-cells in the PFC and development of psychiatric anxiety for neonatal rats exposed to LTIH.

Responsive micellar films of amphiphilic block copolymer micelles: control on micelle opening and closing.

We reported the deliberate control on the micelle opening and closing of amphiphilic polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) micellar films by exposing them to selective solvents. We first treated the micellar films with polar solvents including ethanol and water (pH = 4, 8, and 12) that have different affinities to P2VP. We observed opening of the micelles in all the cases. Both the size of opened pores and the opening rate are dependent on the solvency of different solvents for P2VP. We then explored the closing behavior of the opened micelles using solvents having different affinities to PS. We found that the opened micelles were recovered to their initial closed micelle forms. The recovery was accompanied by a slow micelle disassociation process which gradually reduced the micelle size. The rates of the micelle closing and disassociation are also dependent on the solvency of different solvents for PS.

Analgesic effects of gabapentin on mechanical hypersensitivity in a rat model of chronic pancreatitis.

Gabapentin, an anticonvulsant, is widely accepted as an alternative therapeutic agent for neuropathic pain and has proved to produce analgesic effects in a mouse model of visceral pain. However, it is unknown whether gabapentin is also analgesically effective in chronic pancreatitis. The aim of the present study was to investigate the role and underlying mechanisms of gabapentin in a rat model of chronic pancreatitis. Chronic pancreatitis induced by dibutyltin dichloride (DBTC) produced a marked increase in mechanical sensitivity of the abdomen after the establishment of the model. During the first day to the sixth day in the fourth week, Gabapentin was administered intraperitoneally daily at a dose of 100mg/kg. The behavioral test began 1h after drug administration. The analgesic effect of gabapentin was not evident with a single injection, but gabapentin significantly reduced the responsive frequencies to mechanical stimulation in rats with chronic pancreatitis from the third day to the end of the experiment. To explore the underlying mechanisms, the expression of alpha(2)delta-1 calcium channel subunit was examined in the thoracic spinal cord (T8-11). There was no significant change in alpha(2)delta-1 level of T8-11 following the first injection. But after the sixth injection, the alpha(2)delta-1 level of T8-11 in rats with chronic pancreatitis was declined. Taken together, the present study suggested that repeated administration of gabapentin daily could reduce mechanical hypersensitivity in the upper abdomen and produce an analgesic effect in a rat model of chronic pancreatitis. The down-regulation of alpha(2)delta-1 calcium channel subunit might be one of the mechanisms underlying the analgesic effect of gabapentin.

Blood serum profiling of the rat spinal nerve ligation model using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry.

Peripheral nerve injury, which gives rise to persistent chronic pain, has become an area of intense research activity, largely because it represents a disorder with a high unmet medical need. In this study, serum biomarkers of the spinal nerve ligation model were successfully investigated with the metabolomic method. The regulatory effect of gabapentin, a novel clinical antineuralgia drug, on biomarker levels in serum was also investigated. Rat serum extract samples were analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). A method of supervised multivariate analysis, the partial least squares-discrimination analysis (PLS-DA), was used to validate metabolic changes. In addition, another multivariate method, the orthogonal partial least-squares analysis (OPLS), was used to monitor the real biological variability and to detect potential biomarkers in the spinal nerve ligation model. The results demonstrated that the spinal nerve ligation model had several discriminating ions compared with the control model. Among the detectable metabolites, levels of norepinephrine were increased in the spinal nerve ligation model and were decreased to control levels by gabapentin.