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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]

Background: Sevoflurane (Sev) is an inhalational anesthetic for surgical procedures where it can trigger cognitive dysfunction and neuronal apoptosis. Gyosaponin (GpS) was studied for its effects on brain morphology and cognitive behaviors in Sev-anesthetized rats., Methods: Male Sprague-Dawley rats were induced by 3 % Sev anesthesia, and 25 mg/kg and 100 mg/kg GpS were injected into the rats by 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 HE staining and TUNEL assay. Apoptosis-related proteins and proteins related to the PI3K/Akt/mTOR pathway were determined via Western blot. Also, pro-inflammatory factors were measured via ELISA., Results: GpS diminished the Sev-triggered apoptosis in neurons and Cleaved caspase-3, BAX, TNF-α, IL-6, lessened oxidative stress damage, and stimulated the PI3K/Akt/mTOR pathway. GpS therapy markedly enhanced learning and memory abilities in rats suffering from Sev-related cognitive impairments., Conclusion: GpS ameliorates Sev-induced neurotoxicity and cognitive dysfunction by modulating the PI3K/Akt/mTOR pathway and alleviating neuronal apoptosis and oxidative stress., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024. Published by Elsevier España, S.L.U.)

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]

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]

Objective: This study aimed to analyze the role of mitochondrial Omi/HtrA2 signaling pathway in neuronal apoptosis in patients with cerebral hemorrhage (CH)., Methods: In this retrospective analysis, the clinical data of 60 patients with CH who received craniotomy or minimally invasive intracranial hematoma (MIIH) were included in the case group, which was sub-divided into a craniotomy group (n=22) and a minimally invasive group (n=38) depending on the type of surgery. The brain tissue specimens of the above patients were retained in the surgical specimen repository of Yuhuan Second People's Hospital. Another 15 normal brain tissue samples retained in the surgical specimen repository were included in the normal group. The expression levels of Omi/HtrA2, X-linked inhibitor of apoptosis protein (XIAP), poly-adenosine diphosphate-ribose polymerase (PARP), pro-caspase 3, and pro-caspase 9 were determined using Western blotting., Results: The case group exhibited a higher proportion of neuronal apoptosis, higher expression levels of Omi/HtrA2, PARP, and pro-caspase 3 and 9, higher activities of caspase 3 and caspase 9 ( P < 0.05), and lower XIAP expression ( P < 0.05) in brain tissue than the normal group. The proportion of neuronal cell apoptosis in brain tissues was positively correlated with the expression of Omi/HtrA2, PARP, and pro-caspase 3 and pro-caspase 9 ( r > 0, P < 0.05), and the activity of caspase 3 and caspase 9 was negatively correlated with XIAP expression ( r < 0, P < 0.05). Compared with the craniotomy group, the minimally invasive group demonstrated higher efficacy and hematoma removal rate, shorter hematoma removal time, hematoma drainage time, operation time, and hospital stay, less intraoperative bleeding, and lower postoperative complication rates ( P < 0.05). The minimally invasive group showed higher expression level of serum XIAP and lower levels of serum caspase 3 and caspase 9 than the craniotomy group ( P < 0.05)., Conclusions: Mitochondrial Omi/HtrA2 signaling pathway may be involved in neuronal apoptosis. MIIH has the advantages of high efficacy, high hematoma clearance rate, and few complications for the treatment of CH., Competing Interests: None., (AJTR Copyright © 2023.)

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]

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]

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 MT 2 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 MT 2 /Akt/NF-κB pathway, and such stimulation is important for the prevention of neuronal cell apoptosis under high glucose conditions., (© 2017 The Authors. Journal of Pineal Research Published by John Wiley & Sons Ltd.)

Traumatic brain injury (TBI) is a major cause of injury-related deaths, and the mechanism of TBI has become a research focus, but little is known about the mechanism of microRNAs in TBI. The aim of this study is the role of microRNA-22 (miR-22) in TBI-induced neuronal cell apoptosis. Rat cortical neurons were cultured and the TBI model was induced by scratch injury in vitro, before which miR-22 level was altered by transfection of agomir or antagomir. Lactate dehydrogenase (LDH) release and TUNEL assays were performed to examine neuronal cell injury and apoptosis. The activity of caspase 3 (CASP3) and level changes of several apoptosis factors including B-cell lymphoma 2 (BCL2), BCL2-associated X protein (BAX), phosphatase and tensin homolog (PTEN) and v-AKT murine thymoma viral oncogene homolog 1 (AKT1) were detected. Results showed that TBI model cells possessed a downregulated miR-22 level (P < 0.001) and more LDH release and apoptotic cells indicating the aggravated neuronal cell injury and apoptosis induced by TBI. miR-22 agomir attenuated neuronal cell injury and apoptosis of the TBI model. It also caused the corresponding changes in CASP3 activity and other apoptosis factors, with cleaved CASP3, BAX and PTEN inhibited and BCL2 and phosphorylated AKT1 promoted, while miR-22 antagomir had the opposite effects. So miR-22 has neuroprotective roles of attenuating neuronal cell injury and apoptosis induced by TBI, which may be associated with its regulation on apoptosis factors. This study reveals miR-22 as a potential approach to TBI treatment and detailed mechanism remains to be uncovered.