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Objectives: Adenosine monophosphate-activated kinase (AMPK) is an energy-specific sensor within the central nervous system. In this study, we observed AMPK and its phosphorylated form (pAMPK) in the hippocampal CA1 region after 5 minutes of transient forebrain ischemia. In addition, we also investigated the effects of Compound C, an AMPK inhibitor, against ischemic damage in gerbils. Methods: Adenosine monophosphate-activated kinase and pAMPK immunoreactivity was observed in the hippocampal CA1 region at various time points after ischemia and Compound C was intraperitoneally administered to gerbils immediately after reperfusion and the animals were sacrificed at 5 days after ischemia/reperfusion. Results: Adenosine monophosphate-activated kinase immunoreactivity was transiently increased in the hippocampal CA1 region 1-2 days after ischemia/reperfusion, while AMPK immunoreactivity was almost undetectable in the stratum pyramidale of the CA1 region 4-7 days after ischemia/reperfusion. The administration of Compound C caused a dose-dependent decrease in the ischemia-induced hyperactive behavior, the depletion of ATP, and lactate accumulation in the hippocampal CA1 region within 24 hours after ischemia/reperfusion. In addition, the administration of Compound C decreased reactive gliosis (astrocytes and microglia) and increased the number of cresyl violet-positive neurons when compared to the vehicle-treated group at 5 days post-ischemia/reperfusion. Conclusion: These results suggest that AMPK is transiently phosphorylated following forebrain ischemia in the hippocampal CA1 region and inhibition of AMPK has neuroprotective effects against ischemic damage through the reduction of ATP depletion and lactate accumulation in the hippocampal CA1 region. [ABSTRACT FROM AUTHOR]

Abstract: Delayed neuronal death following transient cerebral ischemia is mixed with apoptosis and necrosis, and the activation of microglia are activated after the ischemic insult. In the present study, we examined the long-term changes in neuronal degeneration and microglial activation in the gerbil hippocampal CA1 region after 5min of transient cerebral ischemia using specific markers for neuronal damage and microliosis. Transient ischemia-induced neuronal death was shown in CA1 pyramidal cells 4days after ischemia/reperfusion (I/R). However, neuronal degeneration of the pyramidal cells were observed up to 45days in the CA1 region after I/R. Microglial activation was also observed in the CA1 region after I/R. Isolectin B4- (IB4) immunoreactive (+) microglia appeared in the CA1 region 4days after I/R. On the other hand, ionized calcium-binding adapter molecule 1 (Iba-1)+ microglia was markedly increased after I/R, and peaked at 15days after I/R. Thereafter, Iba-1 immunoreactivity was decreased with time-dependant manner in the ischemic CA1 region. These results indicate that neuronal degeneration of CA1 pyramidal cells may last about 45days in the CA1 region after ischemic damage, and microglial activation may be diverse according to their function, such as phagocytosis, after I/R. [Copyright &y& Elsevier]

The present study explored the effects of endophilin A1 (SH3GL2) against oxidative damage brought about by H2O2 in HT22 cells and ischemic damage induced upon transient forebrain ischemia in gerbils. Tat-SH3GL2 and its control protein (Control-SH3GL2) were synthesized to deliver it to the cells by penetrating the cell membrane and blood–brain barrier. Tat-SH3GL2, but not Control-SH3GL2, could be delivered into HT22 cells in a concentration- and time-dependent manner and the hippocampus 8 h after treatment in gerbils. Tat-SH3GL2 was stably present in HT22 cells and degraded with time, by 36 h post treatment. Pre-incubation with Tat-SH3GL2, but not Control-SH3GL2, significantly ameliorated H2O2-induced cell death, DNA fragmentation, and reactive oxygen species formation. SH3GL2 immunoreactivity was decreased in the gerbil hippocampal CA1 region with time after ischemia, but it was maintained in the other regions after ischemia. Tat-SH3GL2 treatment in gerbils appreciably improved ischemia-induced hyperactivity 1 day after ischemia and the percentage of NeuN-immunoreactive surviving cells increased 4 days after ischemia. In addition, Tat-SH3GL2 treatment in gerbils alleviated the increase in lipid peroxidation as assessed by the levels of malondialdehyde and 8-iso-prostaglandin F2α and in pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and interleukin-6; while the reduction of protein levels in markers for synaptic plasticity, such as postsynaptic density 95, synaptophysin, and synaptosome associated protein 25 after transient forebrain ischemia was also observed. These results suggest that Tat-SH3GL2 protects neurons from oxidative and ischemic damage by reducing lipid peroxidation and inflammation and improving synaptic plasticity after ischemia. [ABSTRACT FROM AUTHOR]

Phosphoglycerate mutase 1 (PGAM1) is a glycolytic enzyme that increases glycolytic flux in the brain. In the present study, we examined the effects of PGAM1 in conditions of oxidative stress and ischemic damage in motor neuron-like (NSC34) cells and the rabbit spinal cord. A Tat-PGAM1 fusion protein was prepared to allow easy crossing of the blood-brain barrier, and Control-PGAM1 was synthesized without the Tat peptide protein transduction domain. Intracellular delivery of Tat-PGAM1, not Control-PGAM1, was achieved in a time- and concentration-dependent manner. Immunofluorescent staining confirmed the intracellular expression of Tat-PGAM1 in NSC34 cells. Tat-PGAM1, but not Control-PGAM1, significantly alleviated H2O2-induced oxidative stress, neuronal death, mitogen-activated protein kinase, and apoptosis-inducing factor expression in NSC34 cells. After ischemia induction in the spinal cord, Tat-PGAM1 treatment significantly improved ischemia-induced neurological impairments and ameliorated neuronal cell death in the ventral horn of the spinal cord 72 h after ischemia. Tat-PGAM1 treatment significantly mitigated the ischemia-induced increase in malondialdehyde and 8-iso-prostaglandin F2α production in the spinal cord. In addition, Tat-PGAM1, but not Control-PGAM1, significantly decreased microglial activation and secretion of pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α induced by ischemia in the ventral horn of the spinal cord. These results suggest that Tat-PGAM1 can be used as a therapeutic agent to reduce spinal cord ischemia-induced neuronal damage by lowering the oxidative stress, microglial activation, and secretion of pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF-α. [ABSTRACT FROM AUTHOR]

In a previous study, we utilized a proteomic approach and found a significant reduction in phosphatidylethanolamine-binding protein 1 (PEBP1) protein level in the spinal cord at 3 h after ischemia. In the present study, we investigated the role of PEBP1 against oxidative stress in NSC34 cells in vitro, and ischemic damage in the rabbit spinal cord in vivo. We generated a PEP-1-PEBP1 fusion protein to facilitate the penetration of blood-brain barrier and intracellular delivery of PEBP1 protein. Treatment with PEP-1-PEBP1 significantly decreased cell death and the induction of oxidative stress in NSC34 cells. Furthermore, administering PEP-1-PEBP1 did not show any significant side effects immediately before and after ischemia/reperfusion. Administration of PEP-PEBP1 improved the Tarlov's neurological score at 24 and 72 h after ischemia, and significantly improved neuronal survival at 72 h after ischemia based on neuronal nuclei (NeuN) immunohistochemistry, Flouro-Jade B staining, and western blot study for cleaved caspase 3. PEP-1-PEBP1 administration decreased oxidative stress based on malondialdehyde level, advanced oxidation protein products, and 8-iso-prostaglandin F2α in the spinal cord. In addition, inflammation based on myeloperoxidase level, tumor necrosis factor-α level, and high mobility group box 1 level was decreased by PEP-1-PEBP1 treatment at 72 h after ischemia. Thus, PEP-1-PEBP1 treatment, which decreases oxidative stress, inflammatory cytokines, and neuronal death, may be an effective therapeutic strategy for spinal cord ischemia. [ABSTRACT FROM AUTHOR]

Phosphoglycerate mutase 5 (PGAM5), a glycolytic enzyme, plays an important role in cell death and regulation of mitochondrial dynamics. In this study, we investigated the effects of PGAM5 on oxidative stress in HT22 hippocampal cells and ischemic damage in the gerbil hippocampus to elucidate the role of PGAM5 in oxidative and ischemic stress. Constructs were designed with a PEP-1 expression vector to facilitate the intracellular delivery of PGAM5 proteins. We observed time- and concentration-dependent increases in the intracellular delivery of the PEP-1-PGAM5 protein, but not its control protein (PGAM5), in HT22 cells, and morphologically demonstrated the localization of the transduced protein, which was stably expressed in the cytoplasm after 12 h of PEP-1-PGAM5 treatment. PEP-1-PGAM5 treatment significantly ameliorated cell death, reactive oxygen species formation, DNA fragmentation, and the reduction of cell proliferation induced by H 2 O 2 treatment in HT22 cells. In addition, PEP-1-PGAM5 was effectively delivered to the gerbil hippocampus 8 h after treatment, and ischemia-induced hyperlocomotion and neuronal death in the hippocampal CA1 region were significantly alleviated 1 and 4 days after ischemia, respectively. Ischemia-induced microglial activation was also mitigated by treatment with 1.0 mg/kg PEP-1-PGAM5. At 3 h after ischemia, PEP-1-PGAM5 treatment significantly ameliorated the increase in lipid peroxidation, as assessed by malondialdehyde and hydroperoxide levels, and decreased glutathione levels (increases in glutathione disulfide, the oxidized form of glutathione) in the hippocampus. Two days after ischemia, treatment with PEP-1-PGAM5 significantly alleviated the ischemia-induced reduction in glutathione peroxidase activity and further increased superoxide dismutase activity in the hippocampus. The neuroprotective effects of PEP-1-PGAM5 are partially mediated by a reduction in oxidative stress, such as the formation of reactive oxygen species, and increases in the activity of antioxidants such as glutathione peroxidase and superoxide dismutase. • PEP-1-PGAM5 is delivered into HT22 cells with time- and concentration-dependent manner. • PEP-1-PGAM5 alleviates H 2 O 2 -induced ROS formation, DNA fragmentation, and cell death in HT22 cells. • PEP-1-PGAM5 ameliorates ischemic neuronal death in the hippocampus by reducing lipid peroxidation and increasing glutathione. [ABSTRACT FROM AUTHOR]

Abstract: Response to cerebral ischemia in young animals was very different from that in the adult. The aim of this study was to investigate differences in neuronal death and gliosis in the hippocampal CA1 region (CA1) between adult and young gerbils following 5 and 15min of transient cerebral ischemia. Delayed neuronal death (DND) of pyramidal cells occurred in the CA1 was similar in all the adult gerbils after 5 and 15min of ischemia: the DND occurred 4days after ischemia. In the young groups, DND of pyramidal cells in the CA1 region occurred 7 and 3days after 5 and 15min of ischemia, respectively. On the other hand, the activation of GFAP-immunoreactive (+) astrocytes and Iba-1+ microglia was different in the young groups from the adult groups after ischemia. The change pattern of GFAP immunoreactivity in the adult groups was similar in both the adult groups after ischemia; in the young groups, the activation of GFAP+ astrocytes after 5min of ischemia was much delayed than that after 15min of ischemia. Activated Iba-1+ microglia were aggregated in the stratum pyramidale 4days after ischemia in all the adult ischemia-operated groups; in the young groups, activated Iba-1+ microglia were aggregated in the stratum pyramidale 7days after 5min of ischemia and 3days after 15min of ischemia. These observations indicate that DND in young animals is very different from the adult according to different duration of transient cerebral ischemia and glial activation is very different in young animals after different duration of transient ischemia. [Copyright &y& Elsevier]

Abstract: Objective: Because of atlantoaxial complex has a unique and complicated anatomy and instability of this complex is very dangerous. We investigated the clinical results of posterior C1–C2 fixation with a polyaxial screw–rod system. Methods: Between July 2001 and December 2007, the authors treated 17 patients suffering from atlantoaxial deformity and instability. Atlantoaxial fusion was employed in 9 patients with upper cervical fracture and dislocation, in 6 patients with atlantoaxial subluxation, in 1 patient with pure transverse ligament injury, and in 1 patient with basilar invagination. The mean age at the time of surgery was 40.4 years (range, 15–68 years). Results: Operative times ranged from 165 to 420min (average 306min), and the postoperative mean VAS score was 2.4. The mean follow-up period was 26 months. Solid fusion was achieved in 15 patients at the last follow up; no injury of the vertebral artery or spinal cord and no operative mortality occurred in these cases. Conclusions: We suggest that posterior atlantoaxial fixation using the polyaxial screw–rod system is an effective and relatively safe technique. The navigation guidance system employed during the surgical procedure was helpful methods. Future studies of the feasibility of navigation system-guided surgical procedures will be required. [Copyright &y& Elsevier]

Abstract: Transplantation of adipose-derived stem cells (ASCs) is one of the possible therapeutic tools for ischemic damage. In this study, we observed the effects of ASCs against ischemic damage in the ventral horn of L5–6 levels in the rabbit spinal cord. ASCs were isolated from rabbits, and cell type was confirmed by flow cytometry analysis, labeling with CM-DiI dye and differentiation into adipocytes in adipogenesis differentiation medium. ASCs were administered intrathecally into recipient rabbits (2×105) immediately after reperfusion following a 15-min aortic artery occlusion in the subrenal region. Transplantation of ASCs significantly improved functions of the hindlimb and morphology of the ventral horn of spinal cord although CM-DiI-labeled ASCs were not observed in the spinal cord parenchyma. In addition, transplantation of ASCs significantly increased brain-derived neurotrophic factor (BDNF) levels at 72h after ischemia/reperfusion. These results suggest that transplantation of ASCs prevents motor neurons from spinal ischemic damage and reactive gliosis by increasing neurotrophic factors such as BDNF in the spinal cord. [Copyright &y& Elsevier]

Abstract: Cyclooxygenase (COX) is a rate-limiting enzyme in synthesis of prostaglandins from arachidonic acid. In this study, we observed the effects of a physical exercise on COX-2 immunoreactivity in the hippocampus using immunohistochemistry in rats. In addition, we examined effects of administration of a COX-2 inhibitor, celecoxib, on neuroblast differentiation. At 6weeks of age, Zucker lean control (ZLC) and Zucker diabetic fatty (ZDF) rats were put on a treadmill with or without running for 1h/session/day for 5weeks. The running speed was gradually increased from 16 to 22m/min with 2m/min per 2weeks. In the ZLC and ZDF rats, COX-2 immunoreaction was detected in the granule cell layer of the dentate gyrus and in the stratum pyramidale of the CA2/3 region; COX-2 immunoreaction in the CA1 region was hardly detected. In the exercised-ZLC and ZDF rats, COX-2 immunoreactivity was significantly increased compared to that in the ZLC and ZDF rats, showing that COX-2 immunoreactivity in the exercised-ZDF rats was slightly low than that in the exercised-ZDF rats. In addition, weak COX-2 immunoreactivity was shown in the CA1 region by exercise. On the other hand, the repeated oral administration of celecoxib to 4-week-old ZDF rats significantly decreased the neuroblasts in the subgranular zone of the dentate gyrus. These results suggest that COX-2 may be associated with the increase of synaptic plasticity or contacts in the hippocampus. [Copyright &y& Elsevier]

Abstract: Much evidence has been accumulated that the increased expression of calbindin D-28k (CB) is involved in the blockade of calcium-evoked excitotoxicity in cerebral ischemia. We investigated the expression of CB in the basal lamina of microvessels in the ventral horn of the rabbit spinal cord after transient spinal cord ischemia. Spinal cord sections at the level of L7 were immunostained using monoclonal antibody raised against CB at light and electron microscopic levels. CB immunoreactivity was detected in the basal lamina of microvessels at 30 min after ischemic insult. By 3 h after ischemia, CB immunoreactivity was increased in the basal lamina of the microvessels. CB immunoreactivity began to decrease at 6 h after ischemia and nearly disappeared at 48 h after ischemic insult. For calcium detection in the blood vessels of spinal cord, we conducted an alizarin red staining. Alizarin red reactivity was detected in some microvessels at 3 h after ischemic insult. Our results suggest that the ectopic expression of CB in the microvascular basal laminae may be associated with the buffering of calcium in the endothelial cells of microvessels after ischemic damage. [Copyright &y& Elsevier]

We examined ischemia-related changes of calbindin D-28k (CB) immunoreactivity in L7 of the spinal ventral horn after transient spinal cord ischemia in rabbits. In the sham-operated group, CB immunoreactivity was not present in the spinal ventral horn, but CB immunoreactivity was detectable in the dorsal horn. CB immunoreactivity was detectable in the ventral horn at 30min after ischemia: the CB immunoreactivity was found in glial cells identified as astrocytes. At 1h after ischemia, CB immunoreactivity was highest and present at a few somata located in the lamina VII as well as many glial cells. CB immunoreactivity was lower in the lamina VII at 3h after ischemia compared to 1h post-ischemic group. By 2 days after ischemia, CB immunoreactivity was decreased in this region. In addition, the result of Western blot result showed the pattern of CB expression similar to that of immunohistochemistry. In conclusion, the ischemia-related changes of CB immunoreactivity in neurons and glial cells in the ischemic spinal ventral horn in rabbits may be related to modulation of intracellular calcium following transient ischemia. [Copyright &y& Elsevier]

Heat shock protein 70 (HSP70) is an ATP-dependent molecular chaperone, and it has been shown that its levels increase after exposure to various types of stress, including ischemia. In the present study, we investigated the effects of HSP70 against H 2 O 2 -induced neuronal stress in NSC34 cells and against spinal cord ischemia in rabbits. Tat-HSP70 proteins facilitated the intracellular delivery of HSP70 into the NSC34 cells and enabled them to cross the blood-brain barrier in the rabbit spinal cord. Tat-HSP70 was effectively transduced into NSC34 cells in a concentration- and time-dependent manner, while control-HSP70 protein could not be delivered intracellularly at any concentration or time after treatment. Treatment with Tat-HSP70 reduced the generation of reactive oxygen species and cell death induced by H 2 O 2 , while the control-HSP70 did not show any significant effect on the NSC34 cells exposed to H 2 O 2. In rabbit spinal cord, the administration of Tat-HSP70 showed significant amelioration of neurological defects and neuronal death in the ventral horn of spinal cord. In addition, Tat-HSP70 treatment significantly reduced lipid peroxidation and increased Cu, Zn-superoxide dismutase activities in the spinal cord, but glutathione peroxidase and Mn-superoxide dismutase activities remained unchanged. These results suggest that Tat-HSP70, not control-HSP70, decreases cell damage by reducing oxidative stress in NSC34 cells and rabbit spinal cord, and it can be employed for the reduction of neuronal damage caused after spinal cord ischemia. • Tat-HSP70 enables to efficiently transduce into the NSC34 cells. • Tat-HSP70 reduces the H 2 O 2 -induced neuronal death and oxidative damage in the NSC34 cells. • Tat-HSP70 protects motor neurons from spinal cord ischemia by reducing the lipid peroxidation. [ABSTRACT FROM AUTHOR]

Objective: Although adult spinal deformity (ASD) surgery aims to restore and maintain alignment, proximal junctional kyphosis (PJK) may occur. While existing scoring systems predict PJK, they predominantly offer a generalized 3-tier risk classification, limiting their utility for nuanced treatment decisions. This study seeks to establish a personalized risk calculator for PJK, aiming to enhance treatment planning precision., Methods: Patient data for ASD were sourced from the Korean spinal deformity database. PJK was defined a proximal junctional angle (PJA) of ≥ 20° at the final follow-up, or an increase in PJA of ≥ 10° compared to the preoperative values. Multivariable analysis was performed to identify independent variables. Subsequently, 5 machine learning models were created to predict individualized PJK risk post-ASD surgery. The most efficacious model was deployed as an online and interactive calculator., Results: From a pool of 201 patients, 49 (24.4%) exhibited PJK during the follow-up period. Through multivariable analysis, postoperative PJA, body mass index, and deformity type emerged as independent predictors for PJK. When testing machine learning models using study results and previously reported variables as hyperparameters, the random forest model exhibited the highest accuracy, reaching 83%, with an area under the receiver operating characteristics curve of 0.76. This model has been launched as a freely accessible tool at: (https://snuspine.shinyapps.io/PJKafterASD/)., Conclusion: An online calculator, founded on the random forest model, has been developed to gauge the risk of PJK following ASD surgery. This may be a useful clinical tool for surgeons, allowing them to better predict PJK probabilities and refine subsequent therapeutic strategies.

Objective: Notch receptors are heterodimeric transmembrane proteins that regulate cell fate, such as differentiation, proliferation, and apoptosis. Dysregulated Notch pathway signaling has been observed in glioblastomas, as well as in other human malignancies. Nerve growth factor (NGF) is essential for cell growth and differentiation in the nervous system. Recent reports suggest that NGF stimulates glioblastoma proliferation. However, the relationship between NGF and Notch1 in glioblastomas remains unknown. Therefore, we investigated expression of Notch1 in a glioblastoma cell line (U87-MG), and examined the relationship between NGF and Notch1 signaling., Methods: We evaluated expression of Notch1 in human glioblastomas and normal brain tissues by immunohistochemical staining. The effect of NGF on glioblastoma cell line (U87-MG) was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. To evaluate the relationship between NGF and Notch1 signaling, Notch1 and Hes1 expression were evaluated by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. To confirm the effects of NGF on Notch1 signaling, Notch1 and Hes1 small interfering RNAs (siRNAs) were used., Results: In immunohistochemistry, Notch1 expression was higher in glioblastoma than in normal brain tissue. MTT assay showed that NGF stimulates U87-MG cells in a dose-dependent manner. RT-PCR and Western blot analysis demonstrated that Notch1 and Hes1 expression were increased by NGF in a dose-dependent manner. After transfection with Notch1 and Hes1 siRNAs, there was no significant difference between controls and 100 nM NGF-β, which means that U87-MG cell proliferation was suppressed by Notch1 and Hes1 siRNAs., Conclusion: These results indicate that NGF stimulates glioblastoma cell proliferation via Notch1 signaling through Hes 1.

The present study investigated the protective effects of small ubiquitin-like modifier 1 (SUMO-1) on spinal cord ischemic damage in rabbits. A trans‑activator of transcription (Tat)‑SUMO‑1 fusion protein was prepared, and transient spinal cord ischemia was induced by occlusion of the abdominal aorta for 15 min. Vehicle (glycerol) or 1 mg/kg Tat-1-SUMO‑1 was administered intraperitoneally to the rabbits immediately following ischemia/reperfusion. Administration of Tat-SUMO-1 did not lead to significant alterations in arterial blood gases [partial pressure (Pa)CO2 and PaO2], pH, or blood glucose levels prior to ischemia, 10 min after occlusion or 10 min after reperfusion. Mean arterial pressure was significantly decreased only during occlusion. Motor behaviors were assessed at 24, 48 and 72 h after ischemia/reperfusion using Tarlov's criteria. Administration of Tat‑SUMO‑1 significantly improved Tarlov scores 24 h after ischemia/reperfusion and the number of cresyl violet positive neurons was significantly increased in the ventral horn of the spinal cord compared with the vehicle‑treated group. However, Tarlov scores were consistently decreased at 48 and 72 h after ischemia/reperfusion in the Tat‑SUMO‑1‑treated group, and Tarlov scores and the number of cresyl violet positive neurons were not significantly different between the vehicle‑ and Tat‑SUMO‑1‑treated groups after 72 h. Tat-SUMO‑1 administration significantly ameliorated a reduction in Cu, Zn‑superoxide dismutase activity and an increase in lipid peroxidation 24 h after ischemia/reperfusion; however, these effects were not present at 72 h. These results suggested that Tat‑SUMO‑1 may delay, although not protect against, neuronal death by regulating oxidative stress in the ventral horn of the spinal cord and that combination therapy using Tat‑SUMO‑1 with other compounds may provide a therapeutic approach to decrease neuronal damage.

Transient forebrain ischemia depletes glucose and oxygen levels in the brain. In this pathological condition, lactate serves an important role in cellular metabolism as the end product of glycolysis. The present study investigated the expression of monocarboxylate transporter 4 (MCT4) in lactate metabolism in the hippocampal CA1 region following induction of transient forebrain ischemia. MCT4 immunoreactivity was detected in CA1 pyramidal cells of the sham-operated group. Animals from the ischemic group exhibited a transient decrease in MCT4 immunoreactivity in the CA1 region between 30 min and 3 h following ischemia compared with the sham‑operated group. The initial decrease in immunoreactivity observed between 30 min and 3 h following ischemia was followed by an increase at 2 days after the treatment. A significant increase in MCT4 immunoreactivity levels was observed 2 days after ischemia compared with the sham‑operated group. Limited MCT4 immunoreactivity was observed in the pyramidal neurons 3 days after ischemia. At 4‑10 days after ischemia, MCT4 immunoreactivity was detected in the strata radiatum, oriens and pyramidale. Furthermore, MCT4 immunoreactivity levels in the CA1 region exhibited a time‑dependent increase following ischemia. The results indicated that there were transient alterations observed in the localization of MCT4 following the induction of ischemia, and further studies are required to investigate the association between MCT4 expression and lactate metabolism in providing energy to the post‑ischemic brain.

Activated M1 microglia secrete proinflammatory cytokines into damaged brain areas. The present study examined activated M1 microglial morphology and expression in the hippocampal Cornu Ammonis (CA) 1 region, which is vulnerable to transient ischemia. Transient cerebral ischemia was performed for 5 min in gerbils, and neuronal death in the CA1 region following transient cerebral ischemia was confirmed using cresyl violet staining, neuronal nuclear antigen immunohistochemistry and Fluoro‑Jade B histofluorescent staining. In addition, CA1 regions were stained for cluster of differentiation (CD) 74, a marker for activated M1 microglia and a ligand for macrophage migration inhibitory factor In sham‑operated animals, no CD74 immunoreactivity was observed in the hippocampal CA1 region. CD74 immunoreactivity was not observed in the hippocampal CA1 region until 3 days post‑ischemic insult; however, elevated CD74 immunoreactivity was detected in the CA1 region from 5 days post‑ischemia. Double immunofluorescence staining for CD74 and ionized calcium‑binding adapter molecule 1, a marker for M1 microglial cells, confirmed the expression of CD74 on this microglial subtype. These results indicated that M1 microglia are activated late in the hippocampal CA1 region following ischemic stroke. Therefore, optimizing the timing of therapeutic intervention may reduce activated M1 microglial-induced neuronal damage.

In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin (ferritin-H), and transferrin in the gerbil hippocampal CA1 region from 30 minutes to 7 days following transient forebrain ischemia. Relative to sham controls, iron reactivity increased significantly in the stratum pyramidale and stratum oriens at 12 hours following ischemic insult, transiently decreased at 1-2 days and then increased once again within the CA1 region at 4-7 days after ischemia. One day after ischemia, ferritin-H immunoreactivity increased significantly in the stratum pyramidale and decreased at 2 days. At 4-7 days after ischemia, ferritin-H immunoreactivity in the glial components in the CA1 region was significantly increased. Transferrin immunoreactivity was increased significantly in the stratum pyramidale at 12 hours, peaked at 1 day, and then decreased significantly at 2 days after ischemia. Seven days after ischemia, Transferrin immunoreactivity in the glial cells of the stratum oriens and radiatum was significantly increased. Western blot analyses supported these results, demonstrating that compared to sham controls, ferritin H and transferrin protein levels in hippocampal homogenates significantly increased at 1 day after ischemia, peaked at 4 days and then decreased. These results suggest that iron overload-induced oxidative stress is most prominent at 12 hours after ischemia in the stratum pyramidale, suggesting that this time window may be the optimal period for therapeutic intervention to protect neurons from ischemia-induced death.

In this randomized, double-blind, placebo controlled clinical trial, the effects of Dendropanax morbifera ( D. morbifera ) Léveille on heavy metal (cadmium and mercury) excretion as well as on lipid peroxidation and Cu, Zn-superoxide dismutase (SOD1) activity were investigated. For this study, tablets containing placebo or 300 mg of the leaf extract from D. morbifera Léveille were used. A total of 60 eligible healthy subjects were enrolled in this randomized, double-blind, placebo-controlled study. The differences in cadmium, mercury, and malondialdehyde (MDA) levels and SOD1 activity were measured in the serum 60 days after treatment with placebo or D. morbifera Léveille extracts. No significant differences between baseline characteristics and biochemical values were identified in subjects in the placebo and D. morbifera Léveille groups. Serum levels of cadmium, mercury and MDA decreased following consumption of D. morbifera Léveille extracts; however, no significant differences were identified. In addition, female, but not male, subjects who consumed D. morbifera Léveille extracts showed a significant increase in SOD1 activity. This result suggests that chronic consumption of D. morbifera Léveille extract can help to facilitate excretion of cadmium and mercury from serum and increase the antioxidant capacity in humans.

Background: Dendropanax morbifera Léveille has been employed for the treatment of infectious diseases using folk medicine. In this study, we evaluated the antioxidant effects of a leaf extract of Dendropanax morbifera Léveille in the hippocampus of mercury-exposed rats., Methods: Seven-week-old Sprague-Dawley rats received a daily intraperitoneal injection of 5 μg/kg dimethylmercury and/or oral Dendropanax morbifera Léveille leaf extract (100 mg/kg) for 4 weeks. Animals were sacrificed 2 h after the last dimethylmercury and/or leaf extract treatment. Mercury levels were measured in homogenates of hippocampal tissue, a brain region that is vulnerable to mercury toxicity. In addition, we measured reactive oxygen species production, lipid peroxidation levels, and antioxidant levels in these hippocampal homogenates., Results: Treatment with Dendropanax morbifera Léveille leaf extract significantly reduced mercury levels in hippocampal homogenates and attenuated the dimethylmercury-induced increase in the production of reactive oxygen species and formation of malondialdehyde. In addition, this leaf extract treatment significantly reversed the dimethylmercury-induced reduction in the hippocampal activities of Cu, Zn-superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase., Conclusion: These results suggest that a leaf extract of Dendropanax morbifera Léveille had strong antioxidant effects in the hippocampus of mercury-exposed rats.

In this study, we investigated the effects of streptozotocin-induced type 1 diabetes on antioxidant-like protein-1 immunoreactivity, protein carbonyl levels, and malondialdehyde formation, a marker for lipid peroxidation, in the hippocampus. For this study, streptozotocin (75 mg/kg) was intraperitoneally injected into adult rats to induce type 1 diabetes. The three experimental parameters were determined at 2, 3, 4 weeks after streptozotocin treatment. Fasting blood glucose levels significantly increased by 20.7-21.9 mM after streptozotocin treatment. The number of antioxidant-like protein-1 immunoreactive neurons significantly decreased in the hippocampal CA1 region, but not the dentate gyrus, 3 weeks after streptozotocin treatment compared to the control group. Malondialdehyde and protein carbonyl levels, which are modified by oxidative stress, significantly increased with a peak at 3 weeks after malondialdehyde treatment, and then decreased 4 weeks after malondialdehyde treatment. These results suggest that neurons in the hippocampal CA1 region, but not the dentate gyrus, are susceptible to oxidative stress 3 weeks after malondialdehyde treatment.

Expression of c‑Fos in the spinal cord following nociceptive stimulation is considered to be a neurotoxic biomarker. In the present study, the immunoreactivity of c‑Fos in the spinal cord was compared between young adult (2‑3 years in dogs and 6 months in mice) and aged (10‑12 years in dogs and 24 months in mice) Beagle dogs and C57BL/6J mice. In addition, changes to neuronal distribution and damage to the spinal cord were also investigated. There were no significant differences in neuronal loss or degeneration of the spinal neurons observed in either the aged dogs or mice. Weak c‑Fos immunoreactivity was observed in the spinal neurons of the young adult animals; however, c‑Fos immunoreactivity was markedly increased in the nuclei of spinal neurons in the aged dogs and mice, as compared with that of the young adults. In conclusion, c‑Fos immunoreactivity was significantly increased without any accompanying neuronal loss in the aged spinal cord of mice and dogs, as compared with the spinal cords of the young adult animals.

Background: Dendropanax morbifera Léveille is used in herbal medicine as a cancer treatment. In this study, we investigated the effects of Dendropanax morbifera stem extract (DMS) on cadmium (Cd) excretion from the blood and kidney and brain tissues of rats exposed to cadmium, as well as the effects of DMS on oxidative stress and antioxidant levels in the hippocampus after Cd exposure., Methods: Seven-week-old Sprague-Dawley rats were exposed to 2 mg/kg of cadmium by intragastric gavage and were orally administered 100 mg/kg of DMS for 4 weeks. Animals were sacrificed and Cd determination was performed using inductively coupled plasma mass spectrometry. In addition, the effects of Cd and/or DMS on oxidative stress were assayed by measuring reactive oxygen species production, protein carbonyl modification, lipid peroxidation levels, and antioxidant levels in hippocampal homogenates., Results: Exposure to Cd significantly increased Cd content in the blood, kidneys, and hippocampi. DMS treatment significantly reduced Cd content in the blood and kidneys, but not in the hippocampi. Exposure to Cd significantly increased reactive oxygen species production, protein carbonyl modification, lipid peroxidation, total sulfhydryl content, reduced glutathione content, and glutathione reductase activity. In contrast, Cu, Zn-superoxide dismutase (SOD1), catalase (CAT), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) activity in the hippocampus were significantly decreased after exposure to Cd, and administration of DMS significantly inhibited these Cd-induced changes., Conclusion: These results indicate that DMS facilitates cadmium excretion from the kidneys, reduces cadmium-induced oxidative stress in the hippocampus, and modulates SOD1, CAT, GPx, and glutathione-S-transferase activities.

Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging.

Multiple myelomas (MM) are characterized by monoclonal proliferation of immunoglobulin (Ig)-secreting plasma cells. Central nervous system involvement is a rare complication of MM, and it can present as either an intraparenchymal or a leptomeningeal lesion. A 77-year-old woman was transferred from the dementia clinic in July 2012. She had a large heterogeneous signal mass with central necrosis and with pial involvement in the left frontal lobe with destruction of the frontal bone that was observed on computed tomography and magnetic resonance imaging. Multiple punched out radiolucent lesions were also noted on the skull X-ray. Serum protein electrophoresis revealed an IgA-kappa monoclonal gammopathy. External lumbar drainage was helpful for treating the fluid collection underneath the scalp after an orbitozygomatic craniotomy with duroplasty.