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Anesthetic sevoflurane (Sev) causes cognitive dysfunction and neuronal death when used as an anesthetic during surgical procedures. Gynosaponin (GpS) was studied for its effects on brain morphology and cognitive behaviors in Sevanesthetized rats. The present study investigated whether GpS has an effect on Sev anesthesia-induced abnormalities in brain morphology and cognitive behaviors, as well as on apoptosis and inflammation of neurons in rats, and delved into the molecular mechanisms. Male Sprague-Dawley rats were induced by 3% Sev anesthesia, and GpS was injected into the rats via the tail vein. The in vitro model of Sev anesthesia was constructed by treating primary rat hippocampal neurons with 4.1% Sev in the presence of GpS (5, 10, and 20 µM). The neuroprotective effects of GpS against Sev-induced cognitive deficits in rats were evaluated using the open field and Morris water maze tests. The apoptosis of hippocampal neurons was observed using hematoxylin-eosin (HE staining and TUNEL assay. Cleaved caspase-3 expression and reactive oxygen species production in rat hippocampal tissue were measured by immunofluorescence. Apoptosis-related proteins and the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway were determined via Western blot. Pro-inflammatory factors tumor necrosis factor-a and interleukin-6 were measured via ELISA. Levels of malondialdehyde, superoxide dismutase and glutathione were assayed by commercial kits. Viability and apoptosis of hippocampal neurons were detected by Cell Counting Kit-8 and flow cytometry. Expression of cleaved caspase-3, B-cell leukemia/lymphoma 2 protein (Bcl-2) Bcl-2-associated protein (Bax) was determined by Western blot. GpS significantly reduced Sev-induced decline in short-term memory, learning and cognitive abilities, as well as neuronal degeneration apoptosis and inflammatory responses, GpS also lessened oxidative stress damage, and activated the PI3K/Akt/mTOR pathway (p<0.05). GpS therapy enhanced learning and memory abilities in rats suffering from Sev-induced cognitive deficits. The PI3K/Akt/mTOR pathway inhibitor LY294002 reversed the ameliorative effects of high-dose GpS on cognitive deficits and cell damage in primary hippocampal neurons in Sev anesthetized rats (p<0.05). We conclude that GpS ameliorates Sev-induced neurotoxicity and cognitive dysfunction by modulating the PI3K/Akt/mTOR pathway and alleviating neuronal apoptosis and oxidative stress. [ABSTRACT FROM AUTHOR]

BACKGROUND: Animal models of diabetic encephalopathy that have been studied mainly include streptozotocin-induced model, high-sugar and high-fat dietinduced model and spontaneous animal model. Establishing a simple, easy, short-cycle, safe and effective model of diabetic encephalopathy can help to explore the subsequent pathogenesis and screen therapeutic drugs. OBJECTIVE: To further explore and evaluate the method of building diabetic encephalopathy rat models. METHODS: Twenty Sprague-Dawley rats were randomly divided into control (n=10) and model (n=10) groups. Rats in the model group were given a single injection of 45 mg/kg streptozotocin in the left lower abdominal cavity, and those in the control group were given the same amount of citrate buffer. During the experiment, the body mass, feed intake, water intake and blood glucose were measured. After 8 weeks, the glucose tolerance and oxidative stress levels were measured, and the pathological changes of brain tissue and the expression of apoptotic proteins were compared between groups. RESULTS AND CONCLUSION: Compared with the control group, the food intake, water intake, encephalization quotient, blood glucose and area under the blood glucose curve were significantly increased in the model group, while the body mass decreased significantly (P < 0.01). Histopathological examination of the brain showed that compared with the control group, the number of surviving nerve cells was significantly reduced in the model group (P < 0.01), with more significant pathological damage of nerve cells. Compared with the control group, the activities of serum superoxide dismutase, catalase and glutathione in the model group were significantly decreased (P < 0.01), and the content of oxidative malondialdehyde was significantly increased (P < 0.05). The expression levels of apoptosis-related proteins Bax and Caspase-3 in brain tissue increased in the model group compared with the control group, while the expression of Bcl-2 decreased (P < 0.01). In conclusion, an 8-week injection of 45 mg/kg streptozotocin can cause obvious pathological damage to the brain tissue of diabetic rats, to successfully establish the rat model of diabetic encephalopathy. [ABSTRACT FROM AUTHOR]

This study aims to investigate the role of miR-495 in neuronal cell apoptosis after acute spinal cord injury (ASCI). The ASCI rat model was established and the Basso, Beattie, and Bresnahan (BBB) score was assessed. miR-495, PR domain containing 5 (PRDM5), and Bcl-2 expressions were measured by qRT-PCR or western blotting. Neuronal cell line PC-12 was subjected to hypoxia condition to simulate the in vitro ASCI model. PC-12 cell apoptosis was measured by flow cytometry, and the interaction between miR-495 and PRDM5 was confirmed by dual luciferase reporter assay. Results showed that BBB score was significantly decreased in ASCI rats compared with sham rats. miR-495 expression was down-regulated in spinal cord tissue of ASCI rats and hypoxia-induced PC-12 cells, and PRDM5 protein level was up-regulated in spinal cord tissue of ASCI rats and hypoxia-induced PC-12 cells. miR-495 overexpression could reduce apoptosis of PC-12 cells, and up-regulated anti-apoptosis protein Bcl-2 protein level. Moreover, PRDM5 was a target of miR-495, and mRNA and protein levels of PRDM5 were negatively regulated by miR-495. miR-495 overexpression could reduce the hypoxia-induced PC-12 cell apoptosis, while PRDM5 overexpression abolished this inhibiting effect. The agomir-495 was injected into ASCI rats, and Bcl-2 protein level and BBB score were increased, but the PRDM5 overexpression reversed these results. Overall, we concluded that miR-495 could inhibit neuronal cell apoptosis and relieve acute spinal cord injury through inhibiting PRDM5. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to explore the role of miR-582-5p/proteinase-activated receptors type I (PAR-1)/Rho/Rho in neuronal cell apoptosis after cerebral ischemic stroke (CIS).Methods: In vivo mouse model of CIS induced by middle cerebral artery occlusion and in vitro model induced by oxygen-glucose deprivation/reoxygenation (OGD/R) in N2A cells was established. The expressions of miR-582-5p, PAR-1, RhoA, and ROCKII in brain tissues and N2A cells were detected. Neuronal cell apoptosis was detected by flow cytometry.Results: We found that miR-582-5p expression was decreased and the expressions of PAR-1, RhoA, and ROCKII were increased in CIS mice and OGD/R model. Moreover, miR-582-5p negatively regulated PAR-1, and overexpression of miR-582-5p inhibited the activation of Rho/Rho pathway by downregulating PAR-1, thus reducing OGD/R-induced neuronal cell apoptosis.Conclusions: Our results suggested that miR-582-5p overexpression could regulate Rho/Rho-kinase signaling pathway via targeting PAR-1, thereby governing the apoptosis of neuronal cells after CIS. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO), a gaseous signaling molecule, induces apoptosis and mediates neurodegenerative diseases and brain injury. Biglycan (BGN), a member of the small leucine-rich proteoglycan family, was demonstrated to exert anti-apoptosis function in various disease models. However, little is known about the effect of BGN on NO-induced neurotoxicity. Here, for the first time, we reported that BGN protects against NO-induced apoptosis in human neuroblastoma SH-EP1 cells. This is supported by the finding that sodium nitroprusside (SNP), a NO donor, triggered downregulation of BGN in SH-EP1 cells, and over-expression of BGN strikingly attenuated NO-induced nuclear fragmentation and apoptosis of neuronal cells. More importantly, BGN remarkably blocked NO-induced phosphorylation of Erk1/2 and p38 signaling, but not JNK MAPK pathway in neuronal cells. Furthermore, inhibiting Erk1/2 by U0126 or p38 by SB203580 partially protected against NO-induced cell death. Conversely, downregulation of BGN by siRNA aggravated NO-induced neuronal cell death, which was not attenuated by U0126 or SB203580. These findings indicated that BGN, downregulated by NO, prevents NO-induced neuronal cell apoptosis via targeting Erk1/2 and p38 signaling pathways. Our results strongly suggest that BGN could be explored for the prevention of NO-induced neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Hyperglycemia is a representative hallmark and risk factor for diabetes mellitus (DM) and is closely linked to DM-associated neuronal cell death. Previous investigators reported on a genome-wide association study and showed relationships between DM and melatonin receptor (MT), highlighting the role of MT signaling by assessing melatonin in DM. However, the role of MT signaling in DM pathogenesis is unclear. Therefore, we investigated the role of mitophagy regulators in high glucose-induced neuronal cell death and the effect of melatonin against high glucose-induced mitophagy regulators in neuronal cells. In our results, high glucose significantly increased PTEN-induced putative kinase 1 (PINK1) and LC-3B expressions; as well it decreased cytochrome c oxidase subunit 4 expression and Mitotracker™ fluorescence intensity. Silencing of PINK1 induced mitochondrial reactive oxygen species (ROS) accumulation and mitochondrial membrane potential impairment, increased expressions of cleaved caspases, and increased the number of annexin V-positive cells. In addition, high glucose-stimulated melatonin receptor 1B ( MTNR1B) mRNA and PINK1 expressions were reversed by ROS scavenger N-acetyl cysteine pretreatment. Upregulation of PINK1 expression in neuronal cells is suppressed by pretreatment with MT2 receptor-specific inhibitor 4-P-PDOT. We further showed melatonin stimulated Akt phosphorylation, which was followed by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) phosphorylation and nuclear translocation. Silencing of PINK1 expression abolished melatonin-regulated mitochondrial ROS production, cleaved caspase-3 and caspase-9 expressions, and the number of annexin V-positive cells. In conclusion, we have demonstrated the melatonin stimulates PINK1 expression via an MT2/Akt/NF-κB pathway, and such stimulation is important for the prevention of neuronal cell apoptosis under high glucose conditions. [ABSTRACT FROM AUTHOR]

Hypothermia treatment is one of the neuroprotective strategies that improve neurological outcomes effectively after brain damage. Minimally invasive surgery (MIS) has been an important treatment of intracerebral hemorrhage (ICH). Herein, we evaluated the neuroprotective effect and mechanism of MIS joint local cooling lavage (LCL) treatment on ICH via detecting the inflammatory responses, oxidative injury, and neuronal apoptosis around the hematoma cavity in rats. ICH model was established by type IV collagenase caudatum infusion. The rats were treated with MIS 6 h after injection, and then were lavaged by normothermic (37 °C) and hypothermic (33 °C) normal saline in brain separately. The results indicated that MIS joint LCL treatment showed enhanced therapeutic effects against ICH-induced inflammation injury and apoptosis in rats, as convinced by the decline of TUNEL-positive cells, followed by the decrease of IL-1β and LDH and increase of IL-10 and SOD. This study demonstrated that the strategy of using MIS joint LCL may achieve enhanced neuroprotection against ICH-induced inflammation injury and apoptosis in rats with potential clinic application. [ABSTRACT FROM AUTHOR]

Recently, the study of microRNA expression profile has shown that miR-224 was implicated in neuron injury, but the mechanism of miR-224 on regulating neuronal apoptosis is completely unclear until now. Therefore, the current study aims to illuminate the miR-224 and its target gene on the modulation of neuronal cell apoptosis induced by ischemic injury. In this study, we used oxygen/glucose deprivation (OGD)-induced human-derived HCN-2 cells to establish the model of cerebral ischemia injury. We found that miR-224 was upregulated in injured cells (human brain cortical neuron). Using bioinformatics analyses, we found that miR-224 targeted the 3′UTR of spastic paraplegia 7 (SPG7) and the miR-224 inhibitor promoted expression of SPG7 and promoter activity of SPG7 3′UTR. In addition, we further found that miR-224 inhibitor enhanced interaction SPG7 with mitochondrial voltage-dependent anion channel (VDAC1) detected by co-immunoprecipitation in injured cells. The knockdown of SPG7 reduced mitochondrial membrane potential and caused higher mitochondrial calcium retention in injured cells. Knockdown of SPG7 inhibits expression of nicotinic acetylcholine receptor. Besides, the miR-224 inhibitor reduced neuronal cell apoptosis was increased by knockdown of either SPG7 or VDAC1. Overall, miR-224 inhibitor may prevent neuronal cell apoptosis by targeting SPG7 3′UTR and promote interaction SPG7 with VDAC1 after cerebral ischemia. Downregulation of SPG7 induces VDAC1 to form mitochondria permeability transition pore probably by inhibiting expression of nicotinic acetylcholine receptor, resulting in mitochondrial membrane depolarization and higher mitochondrial calcium retention. [ABSTRACT FROM AUTHOR]

Ginkgolide B (GB) has been demonstrated to have a variety of pharmacological actions. Accumulating evidence indicates that GB may exert a protective effect on brain injury. The study was designed to investigate the influence of GB on toll-like receptor 4 (TLR-4) and nuclear factor κB (NF-κB)-dependent inflammatory responses and neuronal cell apoptosis after traumatic brain injury (TBI). Wistar rats were subjected to 5, 10 and 20 mg/kg GB daily for 5 days, intraperitoneally, following TBI. Rats were sacrificed at hour 2, 6 and 12, as well as day 1, 2, 3 and 5 after TBI. The administration of 10 and 20 mg/kg GB could significantly (least-significant difference test: p < 0.05) suppress gene expressions of TLR-4 and NF-κB, lessen concentrations of tumour necrosis factor α, interleukin-1β and interleukin-6, as well as reduce the number of apoptotic neuronal cells in traumatic rat brain tissues, but the administration of 5 mg/kg GB did not ( p > 0.05). However, a clear concentration-response relationship was not found. Thus, GB may inhibit TLR-4 and NF-κB-dependent inflammatory responses, and furthermore lessen neuronal cell apoptosis after TBI, which may support the use of GB for the treatment of TBI. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Oxymatrine is extracted from the traditional Chinese herb Sophora flavescens Ait, possesses anti-inflammatory, anti-oxidative and anti-apoptotic properties, and has been used for the treatment of chronic viral hepatitis and many other diseases. Aims of the study: This study aimed to investigate the effects of oxymatrine on inflammatory response mediated by Toll-like receptor4 (TLR4) and nuclear factor kappa-B (NF-κB), oxidative injury induced by 12/15 lipoxygenase (12/15-LOX), phosphorylated p38 mitogen activated protein kinase (phosphor-p38 MAPK) and cytosolic phospholipase A2 (cPLA2), and neuronal cell apoptosis in rat brain with intracerebral hemorrhage (ICH). Materials and methods: Wistar rats were treated intraperitoneally with 60 or 120mg/kg of oxymatrine daily for 5 days following ICH. The rats were sacrificed at hour 2, 6, 12, 24, 48, 72, and 120 after ICH. The gene expressions of TLR-4 and NF-κB, the levels of TNF-alpha, interleukin-1beta, interleukin-6, 12/15-LOX, phospho-p38 MAPK and cPLA2, and the number of apoptotic neuronal cells in rat brain were determined. Results: Oxymatrine at 120mg/kg significantly suppressed gene expressions of TLR-4 and NF-κB, decreased levels of TNF-alpha, interleukin-1beta and interleukin-6, inhibited synthesis of 12/15-LOX, phospho-p38 MAPK and cPLA2 protein, and mitigated apoptotic neuronal changes following ICH in rat. Conclusion: Oxymatrine at 120mg/kg following ICH inhibits inflammatory responses, oxidative injury, and neuronal cell apoptosis in rats. [Copyright &y& Elsevier]

Abstract: Nesfatin-1 has been demonstrated to possess anti-inflammatory and anti-apoptotic effects in the rat brain with subarachnoid hemorrhage. The study was designed to investigate the influence of nesfatin-1 on inflammatory responses and neuronal cell apoptosis after traumatic brain injury. Wistar rats were subjected to 5, 10 or 20μg/kg of nesfatin-1 at designed time points (0.5, 2, 4 or 8h after head trauma) intraperitoneally. Rats were sacrificed at hours 2, 6 and 12, as well as day 1, 2, 3 and 5 after head trauma. The administration of 10 or 20μg/kg of nesfatin-1 at hour 0.5 after head trauma could significantly suppress gene expressions of nuclear factor kappa-B, lessen concentrations of tumor necrosis factor-alpha, interleukin-1beta and interleukin-6, diminish caspase-3 activity as well as reduce number of apoptotic neuronal cells in traumatic rat brain tissues (P <0.05), but the administration of 5μg/kg of nesfatin-1 not (P >0.05). Moreover, 20μg/kg nesfatin-1 also significantly suppressed the inflammation and neuronal cell apoptosis when applied 2, 4 or 8h after head trauma. However, a clear concentration-response or time-response relationship was not found. These findings suggest that nesfatin-1 may inhibit nuclear factor kappa-B-dependent inflammatory responses, and lessen caspase-3-mediated neuronal cell apoptosis after traumatic brain injury in rats. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: Ginkgolide B (GB) is one of the ginkgolides that have been isolated from leaves and root bark of the Chinese tree Ginkgo biloba L. (Ginkgoaceae), and is a specific and potent antagonist of platelet activating factor. There is a large body of data showing that GB possesses a markedly neuroprotective property against ischemia-induced impairment in vivo and in vitro. Recently it has been found that GB can inhibit the inflammation in the rat brain tissues with ischemia/reperfusion injury and in the astrocytes treated with lipopolysaccharide, as well as protect neurons against beta-amyloid 25–35 and ischemia-induced apoptosis. However, there have been few reports on the influence of GB on intracerebral hemorrhage (ICH). This study was to investigate the effects of intraperitoneal GB on neuronal cell apoptosis, inflammatory cytokines and Toll-like receptor4 (TLR4)/nuclear factor kappa-B (NF-κB) pathway after ICH. Materials and methods: Wistar rats obtained an intraperitoneal injection of 5, 10 and 20mg/kg GB after ICH once a day till day 5. Rats were sacrificed by decapitation at hour 2, 6 and 12, as well as day 1, 2, 3 and 5 after ICH. Gene expressions of TLR-4 and NF-κB, concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) as well as number of apoptotic neuronal cells in hemorrhagic rat brain tissues were determined. Results: The administration of 10 and 20mg/kg GB could significantly suppress gene expressions of TLR-4 and NF-κB, lessen concentrations of TNF-α, IL-1β and IL-6 as well as reduce number of apoptotic neuronal cells in hemorrhagic rat brain tissues by Least-significant Difference test (P <0.05), but the administration of 5mg/kg GB not (P >0.05). However, a clear concentration-response relationship was not found. Conclusions: GB may inhibit TLR4/NF-κB-dependent inflammatory responses, and furthermore lessen neuronal cell apoptosis after ICH, which may support the use of G. biloba extracts for the treatment of ICH. [Copyright &y& Elsevier]

Objective: To investigate the influence of oxymatrine (OMT) on Toll-like receptor 4 (TLR-4)/nuclear factor kappa-B (NF-κB)-dependent inflammatory responses and neuronal cell apoptosis after traumatic brain injury (TBI). Materials and methods: Wistar rats were given an intraperitoneal injection of 60 or 120 mg/kg OMT after TBI once a day till day 5. Rats were killed by decapitation at hours 2, 6 and 12, and days 1, 2, 3 and 5 after TBI. Gene expressions of TLR-4 and NF-κB, concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) as well as the number of apoptotic neuronal cells in traumatic rat brain tissues were determined. Results: The administration of 120 mg/kg OMT could significantly suppress gene expressions of TLR-4 and NF-κB, lessen concentrations of TNF-α, IL-1β and IL-6, and reduce the number of apoptotic neuronal cells in traumatic rat brain tissues by the Mann-Whitney U test ( P < 0.05), but the administration of 60 mg/kg OMT could not ( P > 0.05). Conclusion: OMT may inhibit TLR4/NF-κB-dependent inflammatory responses, and furthermore lessen neuronal cell apoptosis after TBI. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common form of dementia with irreversible neurodegeneration. Accumulation of amyloid beta (Aβ) in the brain is considered to be a major cause of neuronal cell death in AD, but the neurotoxic mechanism of Aβ is not yet fully understood. Here, we focused on the role of microRNAs (miRNAs) in Aβ-induced neuronal cell death. In microarray and RT-qPCR analysis of plasma miRNAs obtained from 5 familiar AD mutations (5xFAD) and wild-type (WT) mice of various ages, miR-16-5p showed a significant age-related change that was accompanied by neuronal cell death in the brain tissue of 5xFAD mice. In addition, increased miR-16-5p was prominent near Aβ plaque-deposition sites in 5xFAD mouse brains. Aβ treatment induced miR-16-5p upregulation and apoptosis in primary cultured mouse cortical neurons and the SH-SY5Y human neuroblastoma cell line. In silico analysis and reporter gene assays indicated that miR-16-5p directly targets the mRNA encoding the anti-apoptotic factor, B cell lymphoma-2 (BCL-2), in the neuronal cell line. Overexpression of miR-16-5p in SH-SY5Y cells downregulated BCL-2 expression and induced apoptosis. These results collectively suggest that the miR-16-5p/BCL-2 axis plays an important role for neuronal cell apoptosis in AD. • Loss of neuron occurred near Aβ plaques in the 5xFAD mouse brains. • miR-16-5p was upregulated by Aβ deposition in in vivo and in vitro AD models. • Upregulation of miR-16-5p caused neuronal cell apoptosis via targeting BCL-2. • Upregulation of miR-16-5p may be a risk factor for neuronal cell apoptosis in AD. [ABSTRACT FROM AUTHOR]