Hypoallergenic and Physicochemical Properties of the A2 ß-Casein Fractionof Goat Milk.

Goat milk has a protein composition similar to that of breast milk and contains abundant nutrients, but its use in functional foods is rather limited in comparison to milk from other sources. The aim of this study was to prepare a goat A2 ß-casein fraction with improved digestibility and hypoallergenic properties. We investigated the optimal conditions for the separation of A2 ß-casein fraction from goat milk by pH adjustment to pH 4.4 and treating the casein suspension with calcium chloride (0.05 M for 1 h at 25°C). Selective reduction of ß-lactoglobulin and αs-casein was confirmed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography. The hypoallergenic property of A2 ß-casein fraction was examined by measuring the release of histamine and tumor necrosis factor alpha from HMC-1 human mast cells exposed to different proteins, including A2 ß-casein fraction. There was no significant difference in levels of both indicators between A2 ß-casein treatment and the control (no protein treatment). The A2 ß-casein fraction is abundant in essential amino acids, especially, branched-chain amino acids (leucine, valine, and isoleucine). The physicochemical properties of A2 ß-casein fraction, including protein solubility and viscosity, are similar to those of bovine whole casein which is widely used as a protein source in various foods. Therefore, the goat A2 ß-casein fraction may be useful as a food material with good digestibility and hypoallergenic properties for infants, the elderly, and people with metabolic disorders.

The association of alcohol consumption with patient survival after organophosphate poisoning: a multicenter retrospective study.

Organophosphate (OP) intoxication remains a serious worldwide health concern, and many patients with acute OP intoxication have also consumed alcohol. Therefore, we evaluated the association of blood alcohol concentration (BAC) with mortality among patients with OP intoxication. We retrospectively reviewed records from 135 patients who were admitted to an emergency department (ED) for OP intoxication between January 2000 and December 2012. Factors that were associated with patient survival were identified via receiver operating characteristic curve, multiple logistic regression, and Kaplan-Meier survival analyses. Among 135 patients with acute OP poisoning, 112 patients survived (overall mortality rate: 17 %). The non-survivors also exhibited a significantly higher BAC, compared to the survivors [non-survivors: 192 mg/dL, interquartile range (IQR) 97-263 mg/dL vs. survivors: 80 mg/dL, IQR 0-166.75 mg/dL; p < 0.001]. A BAC cut-off value of 173 mg/dL provided an area under the curve of 0.744 [95 % confidence interval (CI) 0.661-0.815], a sensitivity of 65.2 %, and a specificity of 81.2 %. A BAC of >173 mg/dL was associated with a significantly increased risk of 6-month mortality in the multiple logistic regression model (odds ratio 4.92, 95 % CI 1.45-16.67, p = 0.001). The Cox proportional hazard model revealed that a BAC of >173 mg/dL provided a hazard ratio of 3.07 (95 % CI 1.19-7.96, p = 0.021). A BAC of >173 mg/dL is a risk factor for mortality among patients with OP intoxication.

Vanillin and 4-hydroxybenzyl alcohol promotes cell proliferation and neuroblast differentiation in the dentate gyrus of mice via the increase of brain-derived neurotrophic factor and tropomyosin-related kinase B.

4-Hydroxy­3-methoxybenzaldehyde (vanillin) and 4-hydroxybenzyl alcohol (4-HBA) are well­known phenolic compounds, which possess various therapeutic properties and are widely found in a variety of plants. In the present study, the effects of vanillin and 4­HBA were first investigated on cell proliferation, as well as neuronal differentiation and integration of granule cells in the dentate gyrus (DG) of adolescent mice using Ki­67, doublecortin (DCX) immunohistochemistry and 5­bromo­2'­deoxyuridine (BrdU)/feminizing Locus on X 3 (NeuN) double immunofluorescence. In both the vanillin and 4­HBA groups, the number of Ki­67+ cells, DCX+ neuroblasts and BrdU+/NeuN+ neurons were significantly increased in the subgranular zone of the DG, as compared with the vehicle group. In addition, the levels of brain­derived neurotrophic factor (BDNF) and tropomyosin­related kinase B (TrkB), a BDNF receptor, were significantly increased in the DG in the vanillin and 4­HBA groups compared with the vehicle group. These results indicated that vanillin and 4­HBA enhanced cell proliferation, neuroblast differentiation and integration of granule cells in the DG of adolescent mice . These neurogenic effects of vanillin and 4­HBA may be closely associated with increases in BDNF and TrkB.

Plasma neutrophil gelatinase-associated lipocalin as an early predicting biomarker of acute kidney injury and clinical outcomes after recovery of spontaneous circulation in out-of-hospital cardiac arrest patients.

AIMS: To determine whether the level of plasma neutrophil gelatinase-associated lipocalin (NGAL) can predict acute kidney injury (AKI) and clinical outcomes after recovery of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest (OHCA). METHODS: We conducted a prospective observational study of consecutive admitted patients with ROSC after OHCA between January 2013 and March 2015. Plasma was collected within 4h of ROSC to determine the level of NGAL. Outcome variables were AKI, 30-day survival, and good neurological outcome (GNO). We evaluated the association between NGAL and outcomes. RESULTS: Fifty-four patients were included. AKI occurred in 26 (48.0%); 15 (27.7%) survived over 30 days and 8 had GNO (14.8%). NGAL was significantly lower in the group with non-AKI, 30-day survival, and GNO. To predict AKI, 30-day survival, and GNO, the area under the receiver operating characteristic curve for NGAL was 0.810, 0.728, and 0.875, respectively. In a logistic regression model, NGAL >189 ngml(-1) was strongly associated with AKI (odds ratio [OR] 7.01, 95% confidence interval [CI]: 1.89-26.01) in a multivariate model. A lower level of NGAL was strongly associated with 30-day survival (OR 6.12, 95% CI: 1.64-23.42 at NGAL <153.5 ngml(-1)) and GNO (OR 19.83, 95% CI: 2.21-178.32 at NGAL <129.5 ngml(-1)) in a univariate model, but was not significantly associated with outcomes in a multivariate model. CONCLUSIONS: Plasma NGAL is a strong predictor of AKI in patients exhibiting OHCA at ICU admission. Lower levels of NGAL are associated with greater chance of 30-day survival and GNO.

Monocarboxylate transporter 4 plays a significant role in the neuroprotective mechanism of ischemic preconditioning in transient cerebral ischemia.

Monocarboxylate transporters (MCTs), which carry monocarboxylates such as lactate across biological membranes, have been associated with cerebral ischemia/reperfusion process. In this study, we studied the effect of ischemic preconditioning (IPC) on MCT4 immunoreactivity after 5 minutes of transient cerebral ischemia in the gerbil. Animals were randomly designated to four groups (sham-operated group, ischemia only group, IPC + sham-operated group and IPC + ischemia group). A serious loss of neuron was found in the stratum pyramidale of the hippocampal CA1 region (CA1), not CA2/3, of the ischemia-only group at 5 days post-ischemia; however, in the IPC + ischemia groups, neurons in the stratum pyramidale of the CA1 were well protected. Weak MCT4 immunoreactivity was found in the stratum pyramidale of the CA1 in the sham-operated group. MCT4 immunoreactivity in the stratum pyramidale began to decrease at 2 days post-ischemia and was hardly detected at 5 days post-ischemia; at this time point, MCT4 immunoreactivity was newly expressed in astrocytes. In the IPC + sham-operated group, MCT4 immunoreactivity in the stratum pyramidale of the CA1 was increased compared with the sham-operated group, and, in the IPC + ischemia group, MCT4 immunoreactivity was also increased in the stratum pyramidale compared with the ischemia only group. Briefly, present findings show that IPC apparently protected CA1 pyramidal neurons and increased or maintained MCT4 expression in the stratum pyramidale of the CA1 after transient cerebral ischemia. Our findings suggest that MCT4 appears to play a significant role in the neuroprotective mechanism of IPC in the gerbil with transient cerebral ischemia.

Novel antiepileptic drug lacosamide exerts neuroprotective effects by decreasing glial activation in the hippocampus of a gerbil model of ischemic stroke.

Lacosamide, which is a novel antiepileptic drug, has been reported to exert various additional therapeutic effects. The present study investigated the neuroprotective effects of lacosamide against transient cerebral ischemia-induced neuronal cell damage in the hippocampal cornu ammonis (CA)-1 region of a gerbil model. Neuronal Nuclei immunohistochemistry demonstrated that pre- and post-surgical treatment (5 min ischemia) with 25 mg/kg lacosamide protected CA1 pyramidal neurons in the lacosamide-treated-ischemia-operated group from ischemic injury 5 days post-ischemia, as compared with gerbils in the vehicle-treated-ischemia-operated group. Furthermore, treatment with 25 mg/kg lacosamide markedly attenuated the activation of astrocytes and microglia in the ischemic CA1 region at 5 days post-ischemia. The results of the present study suggested that pre- and post-surgical treatment of the gerbils with lacosamide was able to protect against transient cerebral ischemic injury-induced CA1 pyramidal neuronal cell death in the hippocampus. In addition, the neuroprotective effects of lacosamide may be associated with decreased activation of glial cells in the ischemic CA1 region.

Increased cyclooxygenase-2 and nuclear factor-κB/p65 expression in mouse hippocampi after systemic administration of tetanus toxin.

Brain inflammation has a crucial role in various diseases of the central nervous system. The hippocampus in the mammalian brain exerts an important memory function, which is sensitive to various insults, including inflammation induced by exo/endotoxin stimuli. Tetanus toxin (TeT) is an exotoxin with the capacity for neuronal binding and internalization. The present study investigated changes in inflammatory mediators in the mouse hippocampus proper (CA1­3 regions) and dentate gyrus (DG) after TeT treatment. The experimental mice were intraperitoneally injected with TeT at a low dosage (100 ng/kg), while the control mice were injected with the same volume of saline. At 6, 12 and 24 h after TeT treatment, changes in the hippocampal levels of inflammatory mediators cyclooxygenase­2 (COX­2) and nuclear factor kappa­B (NF­κB/p65) were assessed using immunohistochemical and western blot analysis. In the control group, moderate COX­2 immunoreactivity was observed in the stratum pyramidal (SP) of the CA2­3 region, while almost no expression was identified in the CA1 region and the DG. COX­2 immunoreactivity was increased by TeT in the SP and granule cell layer (GCL) of the DG in a time­dependent manner. At 24 h post­treatment, COX­2 immunoreactivity in the SP of the CA1 region and in the GCL of the DG was high, and COX­2 immunoreactivity in the SP of the CA2/3 region was highest. Furthermore, the present study observed that NF­κB/p65 immunoreactivity was obviously increased in the SP and GCL at 6, 12 and 24 h after TeT treatment. In conclusion, the present study demonstrated that systemic treatment with TeT significantly increased the expression of COX-2 and NF-κB/p65 in the mouse hippocampus, suggesting that increased COX­2 and NF-κB/65 expression may be associated with inflammation in the brain induced by exotoxins.

Activation of immediate-early response gene c-Fos protein in the rat paralimbic cortices after myocardial infarction.

c-Fos is a good biological marker for detecting the pathogenesis of central nervous system disorders. Few studies are reported on the change in myocardial infarction-induced c-Fos expression in the paralimbic regions. Thus, in this study, we investigated the changes in c-Fos expression in the rat cingulate and piriform cortices after myocardial infarction. Neuronal degeneration in cingulate and piriform cortices after myocardial infarction was detected using cresyl violet staining, NeuN immunohistochemistry and Fluoro-Jade B histofluorescence staining. c-Fos-immunoreactive cells were observed in cingulate and piriform cortices at 3 days after myocardial infarction and peaked at 7 and 14 days after myocardial infarction. But they were hardly observed at 56 days after myocardial infarction. The chronological change of c-Fos expression determined by western blot analysis was basically the same as that of c-Fos immunoreactivity. These results indicate that myocardial infarction can cause the chronological change of immediate-early response gene c-Fos protein expression, which might be associated with the neural activity induced by myocardial infarction.

Ischemic preconditioning inhibits expression of Na(+)/H(+) exchanger 1 (NHE1) in the gerbil hippocampal CA1 region after transient forebrain ischemia.

The participation of Na(+)/H(+) exchanger (NHE) in neuronal damage/death in the hippocampal CA1 region (CA1) induced by transient forebrain ischemia has not been well established, although acidosis may be involved in neuronal damage/death. In the present study, we examined the effect of ischemic preconditioning (IPC) on NHE1 immunoreactivity following a 5min of transient forebrain ischemia in gerbils. The animals used in the study were randomly assigned to four groups (sham-operated-group, ischemia-operated-group, IPC plus (+) sham-operated-group and IPC+ischemia-operated-group). IPC was induced by subjecting animals to 2min of ischemia followed by 1day of recovery. A significant neuronal loss was found in the stratum pyramidale (SP) of the CA1, not the CA2/3, of the ischemia-operated-group at 5days post-ischemia. However, in the IPC+ischemia-operated-group, neurons in the SP of the CA1 were well protected. NHE1 immunoreactivity was not detected in any regions of the CA1-3 of the sham- and IPC+sham-operated-groups. However, the immunoreactivity was apparently expressed in the SP of the CA1-3 after ischemia, and the NHE1immunoreactivity was very weak 5days after ischemia; however, at this point in time, strong NHE1immunoreactivity was found in astrocytes in the CA1. In the CA2/3, NHE1immunoreactivity was slightly changed, although NHE1immunoreactivity was expressed in the SP. In the IPC+ischemia-operated-groups, NHE1 immunoreactivity was also expressed in the SP of the CA1-3; however, the immunoreactivity was more slightly changed than that in the ischemia-operated-groups. In brief, our findings show that IPC dramatically protected CA1 pyramidal neurons and strongly inhibited NHE1 expression in the SP of the CA1 after ischemia-reperfusion. These findings suggest that the inhibition of NHE1 expression may be necessary for neuronal survival from transient ischemic damage.

p63 Expression in the Gerbil Hippocampus Following Transient Ischemia and Effect of Ischemic Preconditioning on p63 Expression in the Ischemic Hippocampus.

p63 is a transcription factor of p53 gene family, which are involved in development, differentiation and cell response to stress; however, its roles in ischemic preconditioning (IPC) in the brain are not clear. In the present study, we investigated the effect of IPC on p63 immunoreactivity caused by 5 min of transient cerebral ischemia in gerbils. IPC was induced by subjecting the gerbils to 2 min of transie ischemia 1 day prior to 5 min of transient ischemia. The animals were randomly assigned to four groups (sham-operated-group, ischemia-operated-group, IPC plus (+)-sham-operated-group and IPC + ischemia-operated-group). The number of viable neurons in the stratum pyramidale of the hippocampal CA1 region (CA1) was significantly increased by IPC + ischemia-operated-group compared with that in the ischemia-operated-group 5 days after ischemic insult. We found that strong p63 immunoreactivity was detected in the CA1 pyramidal neurons in the sham-operated-group, and the immunoreactivity was decreased with time after ischemia-reperfusion. In addition, strong p63 immunoreactivity was newly expressed in microglial cells of the CA1 region from 2 days after ischemia-reperfusion. In all the IPC + sham-operated-groups, p63 immunoreactivity in the CA1 pyramidal neurons was similar to that in the sham-operated-group, and the immunoreactivity was well maintained in the IPC + ischemia-operated-groups after cerebral ischemia. In brief, our present findings show that IPC dramatically protected the reduction of p63 immunoreactivity in the pyramidal neurons of the CA1 region after ischemia-reperfusion, and this result suggests that the expression of p63 may be necessary for neurons to survive after transient cerebral ischemia.

Increased immunoreactivity of c­Fos in the spinal cord of the aged mouse and dog.

Expression of c­Fos in the spinal cord following nociceptive stimulation is considered to be a neurotoxic biomarker. In the present study, the immunoreactivity of c­Fos in the spinal cord was compared between young adult (2­3 years in dogs and 6 months in mice) and aged (10­12 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 c­Fos immunoreactivity was observed in the spinal neurons of the young adult animals; however, c­Fos 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, c­Fos 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.

Effect of transient cerebral ischemia on the expression of receptor for advanced glycation end products (RAGE) in the gerbil hippocampus proper.

The receptor for advanced glycation end products (RAGE) is a multi-ligand receptor of the immunoglobulin superfamily that has been implicated in multiple neuronal and inflammatory stress processes. In this study, we examined changes in RAGE immunoreactivity and its protein levels in the gerbil hippocampus (CA1-3 regions) after 5 min of transient global cerebral ischemia. The ischemic hippocampus was stained with cresyl violet, neuronal nuclei (a neuron-specific soluble nuclear antigen) antibody and Fluoro-Jade B (a marker for neuronal degeneration). 5 days after ischemia-reperfusion, delayed neuronal death occurred in the stratum pyramidale of the CA1 region. RAGE immunoreactivity was not detected in any regions of the CA1-3 regions of the sham-group; the immunoreactivity was markedly increased only in the CA1 region from 3 days after ischemia-reperfusion. On the other hand, RAGE immunoreactivity was newly expressed in astrocytes, not in microglia. Western blot analysis showed that RAGE protein level was highest at 5 days post-ischemia. In brief, both the RAGE immunoreactivity and protein level were distinctively increased in astrocytes in the ischemic CA1 region from 3 days after transient cerebral ischemia. These results indicate that the increase of RAGE expression in astrocytes after ischemia-reperfusion may be related to the ischemia-caused activation of astrocytes in the ischemic CA1 region.

Shikonin suppresses ERK 1/2 phosphorylation during the early stages of adipocyte differentiation in 3T3-L1 cells.

BACKGROUND: The naphthoquinone pigment, shikonin, is a major component of Lithospermum erythrorhizon and has been shown to have various biological functions, including antimicrobial, anti-inflammatory, and antitumor effects. In this study, we investigated the effect of shikonin on adipocyte differentiation and its mechanism of action in 3T3-L1 cells. METHODS: To investigate the effects of shikonin on adipocyte differentiation, 3T3-L1 cells were induced to differentiate using 3-isobutyl-1-methylzanthine, dexamethasone, and insulin (MDI) for 8 days in the presence of 0-2 µM shikonin. Oil Red O staining was performed to determine the lipid accumulation in 3T3-L1 cells. To elucidate the anti-adipogenic mechanism of shikonin, adipogenic transcription factors, the phosphorylation levels of ERK, and adipogenic gene expression were analyzed by Western blotting and quantitative real-time PCR. To further confirm that shikonin inhibits adipogenic differentiation through downregulation of ERK 1/2 activity, 3T3-L1 cells were treated with shikonin in the presence of FGF-2, an activator, or PD98059, an inhibitor, of the ERK1/2 signaling pathway. RESULTS: Shikonin effectively suppressed adipogenesis and downregulated the protein levels of 2 major transcription factors, PPARγ and C/EBPα, as well as the adipocyte specific gene aP2 in a dose-dependent manner. qRT-PCR analysis revealed that shikonin inhibited mRNA expression of adipogenesis-related genes, such as PPARγ, C/EBPα, and aP2. Adipocyte differentiation was mediated by ERK 1/2 phosphorylation, which was confirmed by pretreatment with PD98059 (an ERK 1/2 inhibitor) or FGF-2 (an ERK 1/2 activator). The phosphorylation of ERK1/2 during the early stages of adipogenesis in 3T3-L1 cells was inhibited by shikonin. We also confirmed that FGF-2-stimulated ERK 1/2 activity was attenuated by shikonin. CONCLUSIONS: These results demonstrate that shikonin inhibits adipogenic differentiation via suppression of the ERK signaling pathway during the early stages of adipogenesis.

Current practices for paediatric procedural sedation and analgesia in emergency departments: results of a nationwide survey in Korea.

OBJECTIVE: Procedural sedation and analgesia (PSA) in children has become a standard tool in emergency settings, but no national PSA guidelines have been developed for the emergency department (ED) in Korea. Therefore, we investigated the practice of PSA and the level of adherence to institutional PSA guidelines in EDs of teaching hospitals. METHODS: This study was a cross-sectional, web-based survey. The study subjects were the faculty of EDs from 96 teaching hospitals. The questionnaire was posted on an internet site, and the participants were requested that the questionnaire be answered by email and telephone in May 2009. RESULTS: The questionnaires were completed by 67.7% of the participants. Only 20% of EDs had institutional PSA guidelines, 21.5% of those had discharge criteria and 13.8% of EDs had a discharge instruction form. Residents were administered PSA at 76.9% of EDs. The airway rescue equipment was near the area where PSA was performed in 76.9% of EDs. The most commonly used medication for both diagnostic imaging and painful procedure was oral chloral hydrate (87.7%, 61.5%). In 64.6% of EDs, patients were monitored. In only 21 cases, EDs (50.0%) monitored the patients to recovery after PSA or discharge. CONCLUSIONS: Current PSA for paediatric patients have not been appropriately applied in Korea. Unified PSA guidelines were rare in the hospitals surveyed, and many patients were not monitored over an appropriate duration, nor did they receive adequate medications for sedation by the best trained personnel. Therefore, the national PSA guidelines must be developed and implemented as early as possible.

Lithospermum erythrorhizon suppresses high-fat diet-induced obesity, and acetylshikonin, a main compound of Lithospermum erythrorhizon, inhibits adipocyte differentiation.

Lithospermum erythrorhizon, which has traditionally been used as a vegetable and to make the liquor Jindo Hongju, contains several naphthoquinone pigments, including shikonin. This study aimed to evaluate the antiobesity effects of Lithospermum erythrorhizon ethanol extract (LE) and elucidate the underlying mechanism. C57BL/6J mice were fed a normal or high-fat diet with or without LE supplementation for 8 weeks. LE reduced high-fat diet-induced increases in body weight, white adipose tissue mass, serum triglyceride and total cholesterol levels, and hepatic lipid levels while decreasing lipogenic and adipogenic gene expression. Furthermore, acetylshikonin suppressed adipocyte differentiation in a dose-dependent manner and significantly attenuated adipogenic transcription factor expression in 3T3-L1 cells. These findings suggest that Lithospermum erythrorhizon prevents obesity by inhibiting adipogenesis through downregulation of genes involved in the adipogenesis pathway and may be a useful dietary supplement for the prevention of obesity.

Zanthoxylum piperitum DC ethanol extract suppresses fat accumulation in adipocytes and high fat diet-induced obese mice by regulating adipogenesis.

This study was conducted to determine the anti-obesity effects of Zanthoxylum piperitum DC fruit ethanol extract (ZPE) in 3T3-L1 adipocytes and obese mice fed a high-fat diet. We evaluated the influence of the addition of ZPE to a high-fat diet on body weight, adipose tissue weight, serum and hepatic lipids in C57BL/6 mice. In addition, adipogenic gene expression was determined by Western blot and real-time reverse transcription-PCR analysis. We assessed the effect of ZPE on 3T3-L1 preadipocyte differentiation. ZPE reduced weight gain, white adipose tissue mass, and serum triglyceride and cholesterol levels (p<0.05) in high-fat diet-fed C57BL/6 mice. ZPE decreased lipid accumulation and PPARγ, C/EBPα, SREBP-1, and FAS protein and mRNA levels in the liver. ZPE inhibited in vitro adipocyte differentiation in a dose-dependent manner and significantly attenuated adipogenic transcription factors, such as PPARγ, C/EBPα, and SREBP-1 in 3T3L1 cells. These findings suggest that Z. piperitum DC exerts an anti-obesity effect by inhibiting adipogenesis through the downregulation of genes involved in the adipogenesis pathway.

Hypermethylation of repetitive DNA elements in livers of mice fed an atherogenic diet.

OBJECTIVE: DNA methylation status was examined in C57BL/6J obese mice fed an atherogenic diet (AD) to establish the correlation between epigenetic alterations and obesity-related abnormalities. METHODS: Six-week-old male C57BL/6J mice were fed a normal diet (ND) or AD for 8 wk. Methylation levels of global DNA and repetitive DNA elements in livers of ND-fed mice and AD-fed mice were examined. RESULTS: The total amounts of 5-MeC genomic contents in livers of AD-fed mice were increased as compared with those of ND-fed mice. Hypermethylation of repetitive DNA elements was observed in livers of AD-fed mice. CONCLUSION: Hypermethylation of repetitive DNA elements in livers of AD-fed mice proposes epigenetic changes by nutritional intervention.

Sesaminol glucosides protect ß-amyloid induced apoptotic cell death by regulating redox system in SK-N-SH cells.

We have investigated the neuroprotective effect of sesaminol glucosides (SG) in SK-N-SH cells. SG prevented apoptotic cell death induced by Aß25₋35. In parallel, SK-N-SH cells exposed to Aß25₋35 underwent oxidative stress as shown by the elevated level of intracellular ROS, lipid peroxidation, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation, which were effectively suppressed by SG treatment. Furthermore, SG reversed the activities of catalase and glutathione peroxidase, and restored intracellular GSH levels in Aß25₋35 challenged SK-N-SH cells. In addition, SG inhibited not only Aß25₋35-induced apoptotic features including cleavage of poly(ADP-ribose) polymerase, activation of caspase-3, and activation of caspase-9, but also elevated Bax/Bcl-2 ratio in SK-N-SH cells treated with Aß25₋35. It was also observed that Aß25₋35 stimulated the phosphorylation of mitogen-activated protein kinases (MAPKs), including extracellular protein regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAP kinase. SG inhibited phosphorylation of the JNK, ERK and p38 MAP kinase. These results suggest that SG has a protective effect against Aß25₋35-induced neuronal apoptosis, possibly through scavenging oxidative stress and regulating MAPKs signaling pathways.