Butylphthalide Suppresses Neuronal Cells Apoptosis and Inhibits JNK–Caspase3 Signaling Pathway After Brain Ischemia /Reperfusion in Rats

DL-3-n-butylphthalide for acute ischemic stroke: An updated systematic review and meta-analysis of randomized controlled trials

Background: DL -3-n-butylphthalide (NBP) is widely used as a neuroprotective drug in stroke patients in China. A systematic review in 2010 suggested NBP to be safe and effective at promoting neurological recovery, but could not conclude whether it decreased risk of long-term death or disability. Since numerous randomized controlled trials (RCTs) have been conducted on NBP since 2010, we performed an updated systematic review and meta-analysis of safety and efficacy data.

Method: We searched electronic databases and reference lists to identify RCTs that compared patients who received NBP or not (including placebo). Methodological quality of RCTs was assessed using the Revised Cochrane Risk of Bias Tool 2.0, and data were meta-analyzed using Review Manager 5.4 software.

Results: Fifty-seven RCTs involving 8,747 participants were included. Twenty trials examined NBP as a capsule, 29 as an injection, and 8 as sequential injection-capsule therapy. Meta-analyses showed that NBP treatment was associated with a reduction in composite outcome of death and dependency (risk ratio 0.59, 95% CI 0.42 to 0.83; 260 participants; 2 studies), death (risk ratio 0.32, 95% CI 0.13 to 0.75; 2,287 participants; 10 studies), modified Rankin Scale score (mean difference -0.80, 95% CI -0.88 to -0.72; 568 participants; 4 studies), and an increase in Barthel Index, which assesses the ability to engage in basic activities of daily living (mean difference 11.08, 95% CI 9.10 to 13.05; 2,968 participants; 22 studies). Meta-analyses found that NBP significantly reduced neurological deficit based on National Institute of Health Stroke Scale (mean difference -3.39, 95% CI -3.76 to -3.03; 7.283 participants; 46 studies) and Chinese Stroke Scale (mean difference -4.16, 95% CI -7.60 to -0.73; 543 participants; 4 studies). Of the adverse events reported in 31 trials, elevated transaminase (incidence, 1.39-17.53%), rash (0-1.96%) and gastrointestinal discomfort (1.09-6.15%) were most frequent and no serious adverse events were reported.

Conclusion: This update review confirms that NBP can help acute ischemic stroke patients regain the ability to perform activities of daily living, reduce their neurological deficit and short-term death rates. However, the available evidence on whether NBP reduces risk of long-term death or dependence after ischemic stroke remains insufficient.

Neuroprotective Effects of Alpinia oxyphylla Miq against Mitochondria-Related Apoptosis by the Interactions between Upregulated p38 MAPK Signaling and Downregulated JNK Signaling in the Subacute Phase of Cerebral Ischemia-Reperfusion in Rats

Apoptosis in the penumbra region is the major cell death mechanism occurring during ischemia–reperfusion injury’s early phase. Here, we evaluated how the Alpinia oxyphylla Miq (AOM) affects mitochondria-related apoptosis 3 days after transient middle cerebral artery occlusion (MCAo) and examined the mechanisms underlying the regulation of MAPK-mediated mitochondria-related apoptotic signaling in the peri-infarct cortex in rats. The rats were administered the AOM extract intraperitoneally at doses of 0.2[Formula: see text]g/kg (AOM-0.2[Formula: see text]g), 0.4[Formula: see text]g/kg (AOM-0.4[Formula: see text]g), or 0.8[Formula: see text]g/kg (AOM-0.8[Formula: see text]g) at MCAo initiation. The AOM-0.4[Formula: see text]g and AOM-0.8[Formula: see text]g significantly ameliorated apoptotic cell death and considerably downregulated cytochrome c (cyto c) and cleaved caspase-3 immunoreactivity 3 days after reperfusion. Simultaneously, they significantly downregulated cytosolic p-JNK/JNK, cathepsin B/actin, cyto c/actin, Smac/DIABLO/actin, cleaved caspase-3/actin, and AIF/actin and mitochondrial p53/HSP60 and Bax/HSP60 fractions but upregulated cytosolic p-p38 MAPK/p38 MAPK, p-p90RSK/actin, p-Bad/Bad, p-CREB/actin, and XIAP/actin and cytosolic and mitochondrial Bcl-2/Bax and Bcl-xL/Bax fractions in the peri-infarct cortex. Pretreatment with SB203580 — a p38 MAPK inhibitor — completely abrogated the effects of AOM-0.8[Formula: see text]g on the aforementioned protein expression, whereas treatment with SP600125 — a JNK inhibitor — exerted protective effects similar to those of AOM-0.8[Formula: see text]g. Treatment with 0.4 or 0.8[Formula: see text]g/kg AOM has neuroprotective effects against mitochondria-related apoptosis by suppressing cyto c, Smac/DIABLO, and AIF release from the mitochondria to cytosol. The anti-mitochondria related apoptotic effects of the AOM extract are attributable to the interactions between upregulated p38 MAPK/p90RSK-mediated p-Bad and CREB signaling and downregulated JNK/cathepsin B-mediated Bax and p53 signaling in the peri-infarct cortex 3 days after transient MCAo.

Neuroprotective effects of Senkyunolide I against glutamate-induced cells death by attenuating JNK/caspase-3 activation and apoptosis

Glutamate-induced neurotoxicity is one of the most important pathogenic mechanisms in neurological diseases and is widely used as an in vitro model for ischemic stroke. Senkyunolide I (SEI), an active constituent derived from traditional Chinese medicine Ligusticum chuanxiong Hort. and Angelica sinensis (Oliv.) Diels, has been shown to have beneficial effects against focal cerebral ischemia-reperfusion in rats. However, the mechanisms underlying SEI-mediated neuroprotection remain not well understood. Thus, we explored the influence of SEI in glutamate-mediated injury to mouse neuroblastoma (Neuro2a) cells and determined the mechanisms involved. Neuro2a cells were treated with SEI under exposure to glutamate for 24 h. Cell viability was assessed by using WST-1 reagents, and apoptosis was evaluated using Annexin V-FITC and a PI double staining kit. The protein expression levels of p-AKT, AKT, p-GSK3β, GSK3β, p-p38, p38, p-ERK, ERK, p-JNK, JNK, Bcl-2, Bax, Bcl-xl, p-Bad, Bad, p53, and cleaved caspase-3 were determined by Western blot analysis. Glutamate significantly decreased cell viability and elevated the level of apoptosis. Treatment with SEI reversed those effects. Furthermore, the expression of p-JNK/JNK and cleaved caspase-3 were also reduced after treatment with SEI. Our findings demonstrate that SEI protected Neuro2a cells against glutamate toxicity by regulating JNK/caspase-3 pathway and apoptosis. Thus, SEI maybe a promising candidate for neuroprotection.

Ma xing shi gan decoction eliminates PM2.5-induced lung injury by reducing pulmonary cell apoptosis through Akt/mTOR/p70S6K pathway in rats

The present study was designed to investigate the anti-apoptosis effect of Ma xing shi gan decoction (MXD) on PM2.5-induced lung injury via protein kinase B (Akt)/mTOR/p70S6K pathway. A UPLC-MS/MS system was introduced for component analysis of MXD. Rats were instilled with PM2.5 solution suspension intratracheally to induce acute lung injury. The rats were then orally administered with MXD (16, 8, and 4 g/kg) once a day for 7 consecutive days. The therapeutic effects of MXD were evaluated by Hematoxylin and Eosin (HE) staining. The apoptotic cell death was analyzed by terminal-deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assay. The alterations in cytochrome c (Cytc) and cleaved-caspase-3 (C-caspase-3) were measured by immunohistochemistry (IHC). The expressions of Bax, B-cell lymphoma 2 (Bcl-2), p-Akt, p-mTOR and p-p70S6K were detected by Western blot. In vitro, PM2.5 exposure model was introduced in A549 cell, followed by incubation with MXD-medicated serum. Hoechst staining was used to determine apoptotic rate. The levels of Bax, Bcl-2, p-Akt, p-mTOR and p-p70S6K were detected by Western blot. Our results in vivo indicated that treatment with MXD decreased histopathological changes score, TUNEL-positive cells rate, expressions of Cytc and C-caspase-3. The in vitro results revealed that incubation with MXD-mediated serum decreased apoptotic rate. Both results in vivo and in vitro demonstrated that MXD inhibited pro-apoptotic protein Bax and promoted anti-apoptotic protein Bcl-2 expression. Likewise, MXD activated Akt/mTOR/p70S6K signal pathway, which was also confirmed by Western immunoblotting. In conclusion, MXD attenuates lung injury and the underlying mechanisms may relate to regulating the apoptosis via Akt/mTOR/p70S6K signaling pathway activation.

New insights into targeting mitochondria in ischemic injury

Stroke is the leading cause of adult disability and death worldwide. Mitochondrial dysfunction has been recognized as a marker of neuronal death during ischemic stroke. Maintaining the function of mitochondria is important for improving the survival of neurons and maintaining neuronal function. Damaged mitochondria induce neuronal cell apoptosis by releasing reactive oxygen species (ROS) and pro-apoptotic factors. Mitochondrial fission and fusion processes and mitophagy are of great importance to mitochondrial quality control. This paper reviews the dynamic changes in mitochondria, the roles of mitochondria in different cell types, and related signaling pathways in ischemic stroke. This review describes in detail the role of mitochondria in the process of neuronal injury and protection in cerebral ischemia, and integrates neuroprotective drugs targeting mitochondria in recent years, which may provide a theoretical basis for the progress of treatment of ischemic stroke. The potential of mitochondrial-targeted therapy is also emphasized, which provides valuable insights for clinical research.

Butylphthalide enhances recovery from sudden deafness

OBJECTIVES

Cochlear microcirculation disturbance caused by vasculopathy is a common cause of sudden deafness (SD). Reactive oxygen species (ROS) plays an important role in cochlear injury during ischemia-reperfusion. Butylphthalide can improve microcirculation, reduce ROS formation and inhibit apoptosis. The aim of this study was to investigate the therapeutic effect of butylphthalide on patients with SD.

PATIENTS AND METHODS

The hearing gains from 32 ears treated with butylphthalide were compared with that of 32 ears treated with non-butylphthalide. Butylphthalide capsules was administrated orally on an empty stomach for 10 continuous days. There were no significant differences in audiological and clinical data between butylphthalide and non-butylphthalide groups.

RESULTS

The hearing gain of butylphthalide group at 500, 1000, 2000, and 4000 Hz was significantly higher than that of non-butylphthalide group correspondingly (P<0.01). And, the hearing gain at PTA (pure-tone average of 500, 1000, 2000, and 4000 Hz) in butylphthalide group was significantly higher than that of non-butylphthalide group (P<0.01).

CONCLUSION

The recovery of hearing in butylphthalide group was significantly better than that of non-butylphthalide group. It is confirmed that butylphthalide has a definite therapeutic effect on SD.

Activation of HSP70 impedes tert-butyl hydroperoxide (t-BHP)-induced apoptosis and senescence of human nucleus pulposus stem cells via inhibiting the JNK/c-Jun pathway

The endogenous repair failure of degenerated intervertebral disk (IVD) is highly related to the exhaustion of nucleus pulposus stem cells (NPSCs). Excessive oxidative stress could induce apoptosis and senescence of NPSCs, thus, declining the quantity and quality of NPSCs. Heat shock protein 70 (HSP70) is a family of cytoprotective and antioxidative proteins. However, there is no report on the protective effects of HSP70 on oxidative stress-induced NPSC impairments and underlying mechanisms. In the present study, we treated NPSCs with tert-butyl hydroperoxide (t-BHP) in vitro to simulate an oxidative stress condition. HSP70 inducer TRC051384 was used to evaluate the cytoprotective effects of HSP70. The results suggested that HSP70 impeded t-BHP-mediated cell viability loss and protected the ultrastructure of NPSCs. Moreover, t-BHP could induce mitochondrial apoptosis and p53/p21-mediated senescence of NPSCs, both of which were significantly inhibited in HSP70 activation groups. Excessive oxidative stress and mitochondrial dysfunction reinforced each other and contributed to the cellular damage processes. HSP70 decreased reactive oxygen species (ROS) production, rescued mitochondrial membrane potential (MMP) collapse, and blocked ATP depletion. Finally, our data showed that HSP70 downregulated the JNK/c-Jun pathway. Taken together, activation of HSP70 could protect against t-BHP-induced NPSC apoptosis and senescence, thus, improving the quantity and quality of NPSCs. Therefore, HSP70 may be a promising therapeutic target for IVD degeneration.

Shenshuaikang Enema, a Chinese Herbal Remedy, Inhibited Hypoxia and Reoxygenation-Induced Apoptosis in Renal Tubular Epithelial Cells by Inhibiting Oxidative Damage-Dependent JNK/Caspase-3 Signaling Pathways Using Network Pharmacology

Background

Acute kidney injury (AKI) is a common clinically critical illness with serious consequences for the patients. Shenshuaikang enema (SE) is a Chinese herbal compound that is used to treat AKI in clinical practice. However, its mechanism of action remains unclear.

Aim

The aim of this study was to investigate the therapeutic effect of SE and explore the molecular mechanisms using network pharmacology and in vitro experiments.

Materials and Methods

The herb-component-target network was constructed based on network pharmacology. The predicted targets and pathways were validated using in vitro experiments. A renal tubular epithelial cell line (HK-2 cells) was exposed to hypoxia and reoxygenation (H/R) using air-tight conditions for five hours and treated with different concentrations of SE (25%, 50%, and 75%) to assess cell viability and apoptosis and determine the optimal experimental dose. Subsequently, H/R-injured HK-2 cells were pretreated with the optimal SE dose and then randomly divided into three groups, the SE, SE-SP600125 (inhibitor of JNK), and SE-NAC (antioxidant) groups. The cell vitality, apoptosis, and death were evaluated using the cell counting kit 8 (CCK8) and carboxyfluorescein succinimidyl ester/propidium iodide (CFSF/PI) staining. The apoptosis-related protein JNK and Caspase-3 were assessed by Western blot. Expression of JNK and Caspase-3 genes was analyzed using real-time quantitative polymerase chain reaction (RT-qPCR).

Results

123 active components and 226 targets were identified from four herbs that composed the herb-compound-target network based on transcriptomics and network pharmacology analyses. The KEGG pathway analyses revealed that the mitochondrial apoptosis pathway was involved in the therapeutic AKI effects of SE. Cell vitality of H/R-induced HK-2 cells was obviously increased when treating them with SE, and the apoptosis was significantly inhibited, especially in the SE (50%) group at 4 and 12 h after modeling. Pretreatment with antioxidant NAC obviously prevented cell death compared to the SE (50%) group, while no obvious reduction of apoptosis was observed in the SP600125 group. JNK expression level was significantly increased in the SE (50%) group compared to the SP600125 (P < 0.01) and the NAC group (P < 0.05). Caspase-3 was downregulated in the SE (50%) group compared to the SP600125 (P < 0.01) and NAC group (P < 0.05). Caspase-3 activation in the SP600125 group was higher than that in the NAC group (P < 0.05). Moreover, the oxidative damage-dependent JNK/Caspase-3 pathway was identified in the H/R-injured HK-2 cells by inhibiting the JNK activation and oxidative damage.

Conclusions

Our findings suggested that the H/R-triggered apoptosis in HK-2 cells was abrogated by SE by upregulating the oxidative damage-dependent JNK to trigger suppression of Caspase-3.

LncRNA SNHG3 promotes autophagy-induced neuronal cell apoptosis by acting as a ceRNA for miR-485 to up-regulate ATG7 expression

Long non-coding RNAs (lncRNAs) are bound up with various human diseases. However, their roles in brain ischemia-reperfusion (I/R) injury remain largely unknown. This study aimed to reveal the potential mechanism of LncRNA SNHG3 on autophagy-induced neuronal cell apoptosis in the brain I/R injury. LncRNA SNHG3 and miR-485 or autophagy markers LC3II/I and Beclin-1 expressions were detected by qRT-PCR or Western blot and the apoptosis of N2a cells was analyzed by flow cytometry. Besides, the interactions between LncRNA SNHG3 and miR-485, miR-485 and ATG7 were validated by RNA pull-down and dual-luciferase reporter system assays. After the Oxygen and Glucose Deprivation (OGD) treatment of N2a cells transfected with pcDNA-SNHG3, pcDNA-SNHG3 + miR-485 mimic for 6 h, 1 mM autophagy inhibitor 3-MA was added and reoxygenated for 24 h, the effect of LncRNA SNHG3 on the autophagy-induced neuronal cell apoptosis was measured by Western blot and flow cytometry. LncRNA SNHG3 was highly expressed in the mouse model of transient middle cerebral artery occlusion and cell model of Oxygen and Glucose Deprivation/Reperfusion, while miR-485 was lowly expressed. Furthermore, miR-485 negatively regulated the luciferase activities of LncRNA SNHG3 and ATG7. After the OGD treatment of N2a cells transfected with pcDNA-SNHG3, pcDNA-SNHG3 + miR-485 mimic for 6 h, 1 mM 3-MA was added and reoxygenated for 24 h, the overexpression of LncRNA SNHG3 raised the ratio of LC3-II/LC3-I and Beclin-1 expression and boosted the apoptosis of N2a cells, while these effects were reversed after the transfection of miR-485 mimic. In general, our data expounded that the interference with LncRNA SNHG3 improved brain I/R injury by up-regulating miR-485 and down-regulating ATG7 to restrain autophagy and neuronal cell apoptosis.

Dl-3-n-butylphthalide attenuates hypoxic-ischemic brain injury through inhibiting endoplasmic reticulum stress-induced cell apoptosis and alleviating blood-brain barrier disruption in newborn rats

Dl-3-n-butylphthalide (NBP) has been demonstrated to exert neuroprotective effects in experimental models and human patients. This study was performed to assess the therapeutic effects and the underlying molecular mechanisms of NBP in a neonatal hypoxic-ischemic rat model. The results showed that NBP treatment significantly reduced the infarct volume, improved histological recovery, decreased neuronal cell loss, enhanced neuronal cell rehabilitation, promoted neurite growth and decreased white matter injury. In addition, NBP treatment effectively improved long-term neurobehavioral development and prognosis after HI injury. We further demonstrated an inhibitory effect of NBP on endoplasmic reticulum (ER) stress-induced apoptosis, evidenced by reduction in ER stress-related protein expressions (GRP78, XBP-1, PDI and CHOP), decrease in TUNEL-positive cells, down-regulation in pro-apoptosis protein (Bax and cleaved caspase-3), up-regulation in anti-apoptosis protein (Bcl-2). Moreover, NBP exerted a protective effect in blood-brain barrier disruption, which ameliorated brain edema and reduced the degeneration of the tight junction proteins (Occludin and Claudin-5) and adherens junction proteins (P120-Catenin, VE-Cadherin and β-Catenin). Overall, our findings demonstrated that NBP treatment attenuated HI brain injury through inhibiting ER stress-induced apoptosis and alleviating blood-brain barrier disruption in newborn rats. This work provides an effective therapeutic strategy to reduce brain damage and enhance recovery after neonatal HI brain injury.

From Seeds of Apium graveolens Linn. to a Cerebral Ischemia Medicine: The Long Journey of 3-n-Butylphthalide

3-n-Butylphthalide (NBP) as well as its derivatives and analogues (NBPs), in racemic or enantiomerically pure forms, possess potent and diverse pharmacological properties and have shown a great potential therapeutic interest for many human conditions, especially for cerebral ischemia. This Perspective outlines the synthesis and therapeutic applications of NBPs.

Vision treatment strategy for acute blindness in adolescent female with diffuse leptomeningeal glioneuronal tumor

Diffuse leptomeningeal glioneuronal tumor with the first symptom of acute rapid blindness in both eyes are rare in adolescents. We present a case of an adolescent female without a history of cancer who developed a dramatic loss of vision and eventually blindness, and was diagnosed as diffuse leptomeningeal glioneuronal tumor by cerebrospinal fluid cytology and enhanced MRI. In order to save vision, under the condition of ineffective dehydration treatment, timely emergency surgery to implant Ommaya sac drainage cerebrospinal fluid. According to the pathophysiological mechanism of cerebral edema, we added Edaravone to scavenge oxygen free radicals, Alprostadil to improve microcirculation, Monosialotetrahexosylganglioside nutrient nerve, Butylphthalide to promote collateral circulation, combined with hyperbaric oxygen and acupoint injection of Anisodine. Finally, the patient's vision returned to normal. Conclusion: when dehydration treatment is ineffective, timely surgery to reduce intracranial pressure, combined with comprehensive treatment, can effectively save vision.

Golgi reassembly and stacking protein 65 downregulation is required for the anti-cancer effect of dihydromyricetin on human ovarian cancer cells

Golgi reassembly and stacking protein 65 (GRASP65), which has been involved in cancer progression, is associated with tumor growth and cell apoptosis. Dihydromyricetin (DHM) has demonstrated antitumor activity in different types of human cancers. However, the pharmacological effects of DHM on ovarian cancer (OC) and the molecular mechanisms that underlie these effects are largely unknown. The present study showed that DHM reduced cell migration and invasion in a concentration- and time-dependent manner and induced cell apoptosis primarily through upregulation of Cleaved-caspase-3 and the Bax/Bcl-2 ratio in OCs. To further clarify the cancer therapeutic target, we assessed the effect of DHM on the expression of GRASP65, which is overexpressed in human ovarian cancer tissues. DHM activated caspase-3 and decreased GRASP65 expression to promote cell apoptosis, implying that downregulation of GRASP65 was related to DHM-induced cell apoptosis. Additionally, the knockdown of GRASP65 by siRNA resulted in increased apoptosis after DHM treatment, while western blot and flow cytometry analysis demonstrated that overexpression of GRASP65 attenuated DHM-mediated apoptosis. In addition, the JNK/ERK pathway may be involved in DHM-mediated caspase-3 activation and GRASP65 downregulation. Taken together, these findings provide novel evidence of the anti-cancer properties of DHM in OCs, indicating that DHM is a potential therapeutic agent for ovarian cancer through the inhibition of GRASP65 expression and the regulation of JNK/ERK pathway.

[JNK/c-Jun signaling pathway mediates arginine vasopressin neuron regeneration by promoting cytoskeleton reconstruction in rats with electrical lesions of the pituitary stalk]

OBJECTIVE

To investigate the mechanism by which doublecortin promotes the recovery of cytoskeleton in arginine vasopressin (AVP) neurons in rats with electrical lesions of the pituitary stalk (PEL).

METHODS

Thirty-two SD rats were randomized into PEL group with electrical lesions of the pituitary stalk through the floor of the skull base (n=25) and sham operation group (n=7), and the daily water consumption (DWC), daily urine volume (DUV) and urine specific gravity (USG) of the rats were recorded. Four rats on day 1 and 7 rats on each of days 3, 7 and 14 after PEL as well as the sham-operated rats were sacrificed for detection of the expressions of β-Tubulin (Tuj1), doublecortin and caspase- 3 in the AVP neurons of the supraoptic nucleus using immunofluorescence assay and Western blotting.

RESULTS

After PEL, the rats exhibited a typical triphasic pattern of diabetes insipidus, with the postoperative days 1-2 as the phase one, days 3-5 as the phase two, and days 6-14 as the phase three. Immunofluorescent results indicated the repair of the AVP neurons evidenced by significantly increased doublecortin expressions in the AVP neurons following PEL; similarly, the expression of Tuj1 also increased progressively after PEL, reaching the peak level on day 7 after PEL. The apoptotic rates of the AVP neurons exhibited a reverse pattern of variation, peaking on postoperative day 3 followed by progressive reduction till day 14. Western blotting showed that the expressions of c-Jun and p-c-Jun were up-regulated significantly on day 3 (P < 0.05) and 7 (P < 0.01) after PEL, while an upregulated p-JNK expression was detected only on day 3 (P < 0.05), as was consistent with the time-courses of neuronal recovery and apoptosis after PEL.

CONCLUSIONS

JNK/c-Jun pathway is activated after PEL to induce apoptosis of AVP neurons in the acute phase and to promote the repair of neuronal cytoskeleton by up-regulation of doublecortin and Tuj1 expressions.

Echinocystic acid, a natural plant extract, alleviates cerebral ischemia/reperfusion injury via inhibiting the JNK signaling pathway

Echinocystic acid (EA) was found to possess antiviral, anti-inflammatory and antioxidation activities. A recent study showed the antiapoptotic effects of EA on acute myocardial infarction. In this study, we demonstrated the potential neuroprotective effects of EA on cerebral ischemia/reperfusion (I/R) injury in mice. Intraperitoneal injection of EA 1 h before ischemia significantly reduced the cerebral infarct volume and neurological deficit after 60 min of ischemia and 24 h of reperfusion. The neuroprotective effects of EA occurred in a dose-dependent manner. Then, we explored the mechanisms of neuroprotection by EA. This compound exerted antiapoptotic activity by upregulating the level of Bcl-2 and simultaneously downregulating the levels of cleaved caspase-3 and Bax. Furthermore, EA also possessed anti-inflammatory activity and prevented the excessive phosphorylation of NF-κB (p-P65) and the increase in IL-1β and IL-6 levels. Finally, our data indicated that EA treatment decreased the level of phosphorylated JNK in vivo, and the JNK activator anisomycin (AN) reversed the neuroprotective effects of EA, indicating that the JNK pathway is involved in the antiapoptotic and anti-inflammatory mechanisms of EA. In summary, our findings suggest that EA provides neuroprotective effects through its antiapoptotic and anti-inflammatory activities by inhibiting the JNK signaling pathway in cerebral I/R injury. Due to its safety and lack of toxicity, EA is a potential candidate for the treatment of ischemic stroke in future clinical trials.

Learning and memory deficits and alzheimer's disease-like changes in mice after chronic exposure to microcystin-LR

Previous studies have demonstrated that toxins produced by toxic cyanobacterial blooms are hazardous materials. Although microcystin-LR (MC-LR) has been revealed to inflict damage to the brain, the mechanisms underlying its neurotoxicity as a result of chronic exposure to MC-LR are not fully described. In this study, the mice were exposed to MC-LR dissolved in drinking water at doses of 1, 7.5, 15, or 30 μg/L for 180 days. MC-LR accumulated mostly in the mouse hippocampus (55 ng/g dry weight) followed by cortex (28 ng/g dry weight) after exposure to MC-LR at 30 μg/L. MC-LR exposure at this concentration induced dysfunction of learning and memory, accompanied with apoptosis of neuronal cells (with 10% reduction of the neurons in the CA1 region and 15% in the CA2 region), reduction of spine density, accumulation of β-amyloid plaques 1-42 (Aβ1-42), and enhanced phosphorylation of tau (p-tau) in the brain, which is characteristic of Alzheimer's disease (AD). These data indicate that MC-LR may induce AD-like pathology. Following prolonged exposure, MC-LR significantly upregulated the ratio of proBDNF to BDNF by downregulating the tPA levels, thereby activating downstream signaling pathways to improve the expression of p-JNK, and c-Jun while to inhibit the expression of p-Creb and p-PKC. This study uncovered new molecular mechanisms that account for neurotoxicity after chronic exposure to MC-LR, which has wide-ranging implications for public health.

L-3-n-Butylphthalide reduces ischemic stroke injury and increases M2 microglial polarization

Overwhelming evidence suggests that microglia play an important role in ischemic injury and they polarize into two different phenotypes with distinct functions after ischemic stroke. We performed the present study to investigate whether L-3-n butylphthalide (NBP) has an effect on microglial polarization. Mice were subjected to transient middle cerebral artery occlusion (MCAO) for 45 min, and then immediately after reperfusion were treated with NBP or vehicle via the caudal vein for 7 consecutive days. 2,3,5-Triphenyltetrazolium chloride (TTC) staining showed that NBP treatment resulted in a tendency to decrease cerebral infarct volume at 1 day after MCAO, and significant decreased infarct volume at 3 days after MCAO. Sensorimotor function was evaluated by the adhesive removal test and balance beam test, which were superior in NBP-treated mice compared with vehicle-treated mice at 1 and 3 days after MCAO. Immunofluorescent staining further indicated that NBP treatment significantly increased the number of CD206⁺/Iba1⁺ M2 microglia/macrophages and reduced the number of CD16⁺/Iba1⁺ M1 cells at 3 and 7 days after MCAO reperfusion. Western blot also showed an elevation of M2 marker (arginase-1) in NBP-treated brains at 7 days after MCAO. In conclusion, our results clearly show that NBP treatment significantly mitigates ischemic brain damage and promotes recovery of neurological function in early phase after ischemic stroke, probably by skewing M1 microglia/macrophages polarization towards M2 phenotype. Thus, our study provides new evidence that NBP might be a promising candidate for ameliorating injury caused by ischemic stroke.

A UHPLC-MS/MS method coupled with liquid-liquid extraction for the quantitation of phenacetin, omeprazole, metoprolol, midazolam and their metabolites in rat plasma and its application to the study of four CYP450 activities

Drug-drug interactions (DDIs) are thought to be associated with the inhibition of cytochrome P450 activities. The cocktail method with analysis of the metabolism of two or more probe drugs is used to determine CYP450 activities. In this study, we established a UHPLC-MS/MS method for simultaneous quantitation of four CYP450 probe drugs (phenacetin, omeprazole, metoprolol and midazolam) and their metabolites (acetaminophen, 5'-hydroxy omeprazole, α-hydroxy metoprolol and 1'-hydroxy midazolam) in rat plasma. Sample preparation by plasma protein precipitation was combined with a liquid-liquid extraction method. The separation was carried out on a ZORBAX Eclipse Plus C18 Rapid Resolution High Definition column with a gradient elution, using water containing 0.1% formic acid (A) and acetonitrile (B) in a run time of only 3.0 min. Detection was conducted with a 6420 series triple-quadrupole tandem mass spectrometer, using ESI in positive ion mode with multiple reaction monitoring (MRM). The calibration curves were linear over the concentration range 10-5000 ng/mL for phenacetin, omeprazole, metoprolol and midazolam, and 1-500 ng/mL for their metabolites. Intra- and inter-day precisions were within 15%, and the accuracies were in the range of 87-112%. The method was successfully applied to the pharmacokinetic study of probe drugs/metabolites and DDIs with 3-n-butylphthalide (NBP) after administration of a single oral dose of phenacetin, omeprazole, metoprolol and midazolam in rats.

Dl-3-n-Butylphthalide improves lipopolysaccharide-induced depressive-like behavior in rats: involvement of Nrf2 and NF-κB pathways

RATIONALE AND OBJECTIVES

Dl-3-n-Butylphthalide (NBP), a small molecule compound extracted from the seeds of Apium graveolens, possesses a large range of biological effects. Here, we attempted to explore the therapeutic effects of NBP on lipopolysaccharide (LPS)-induced major depressive disorder (MDD) and gain further insight into the underlying mechanisms of the antidepressant effects of NBP.

METHODS

We evaluated the effect of NBP against LPS-induced behavioral changes in rats. We also examined the inflammation, oxidative stress, and apoptosis markers and analyzed the Nrf2 and NF-κB pathways in the hippocampus of rats following repeated peripheral immune challenge by LPS for 2 weeks (500 μg/kg every other day).

RESULTS

Our results indicated that repeated LPS administration induced the rats to a depressive-like state and activated inflammatory response, oxidative stress, and apoptosis reactions in the hippocampus. NBP treatment attenuated the LPS-induced abnormal behavior and ameliorated pathogenic processes in rats with MDD. NBP reduced the inflammatory response with inhibited expression of pro-inflammatory cytokines including IL-1β and IL-6 and downregulated the NF-κB signal pathway. Concurrent with the anti-inflammation action, NBP reduced LPS-induced oxidative reactions in the hippocampus and enhanced Nrf2-targeted signals, as evidenced by increased transcription of antioxidant enzymes and decreased malondialdehyde (MDA) production. In addition, NBP inhibited LPS-induced neuronal apoptosis in the rat brain, as evidenced by decreased apoptosis marker Caspase-3 production and TUNEL assay.

CONCLUSIONS

These results provide more insight into pathogenesis of MDD and firstly demonstrated the potential antidepressant actions of NBP.

c-Jun N-Terminal Kinases (JNKs) in Myocardial and Cerebral Ischemia/Reperfusion Injury

In this article, we review the literature regarding the role of c-Jun N-terminal kinases (JNKs) in cerebral and myocardial ischemia/reperfusion injury. Numerous studies demonstrate that JNK-mediated signaling pathways play an essential role in cerebral and myocardial ischemia/reperfusion injury. JNK-associated mechanisms are involved in preconditioning and post-conditioning of the heart and the brain. The literature and our own studies suggest that JNK inhibitors may exert cardioprotective and neuroprotective properties. The effects of modulating the JNK-depending pathways in the brain and the heart are reviewed. Cardioprotective and neuroprotective mechanisms of JNK inhibitors are discussed in detail including synthetic small molecule inhibitors (AS601245, SP600125, IQ-1S, and SR-3306), ion channel inhibitor GsMTx4, JNK-interacting proteins, inhibitors of mixed-lineage kinase (MLK) and MLK-interacting proteins, inhibitors of glutamate receptors, nitric oxide (NO) donors, and anesthetics. The role of JNKs in ischemia/reperfusion injury of the heart in diabetes mellitus is discussed in the context of comorbidities. According to reviewed literature, JNKs represent promising therapeutic targets for protection of the brain and the heart against ischemic stroke and myocardial infarction, respectively. However, different members of the JNK family exert diverse physiological properties which may not allow for systemic administration of non-specific JNK inhibitors for therapeutic purposes. Currently available candidate JNK inhibitors with high therapeutic potential are identified. The further search for selective JNK3 inhibitors remains an important task.

Hydrogen saline suppresses neuronal cell apoptosis and inhibits the p38 mitogen‑activated protein kinase‑caspase‑3 signaling pathway following cerebral ischemia‑reperfusion injury

Cerebral ischemia-reperfusion injury (CIRI) is a serious pathological disease that is associated with a high rate death and disability. Saturated hydrogen (H₂) saline exhibits brain protective functions through anti-inflammatory, antioxidant and antiapoptotic effects. The present study investigated the potential treatment effects of H₂ on CIRI. In addition, the potential protective mechanisms of H₂ in the prevention of CIRI were investigated. Adult, male Sprague-Dawley rats (n=60) were randomly divided into the following three groups: Sham-operated group; IR group; and IR + H₂ group (0.6 mmol/l, 0.5 ml/kg/day). Hematoxylin and eosin, and TUNEL staining were performed for histopathological analysis and investigation of apoptosis, respectively. In addition, the protein expression of caspase-3, p38 mitogen-activated protein kinase (MAPK) and phosphorylated-p38 MAPK in the cortex were measured by western blotting analysis. These results demonstrated that H₂ significantly reduced the number of apoptotic cells, and the protein expression of p38 MAPK and caspase-3, compared with the IR group. These effects may be associated with the p38MAPK signaling pathway.

Rosmarinic acid protects rat hippocampal neurons from cerebral ischemia/reperfusion injury via the Akt/JNK3/caspase-3 signaling pathway

Cerebral ischemia/reperfusion injury can result in neuronal death, which further results in brain damage and can even lead to death. Although recent studies showed that rosmarinic acid (RA) exerts neuroprotective effects and attenuates ischemia-induced brain injury and neuronal cell death, little is known about the precise mechanisms that occur during cerebral ischemia/reperfusion (I/R). Therefore, the aim of this study was to examine the underlying mechanism of the neuroprotective effects of RA against ischemic brain injury induced by cerebral I/R. Transient global brain ischemia was induced by 4-vessel occlusion in adult male Sprague-Dawley rats. We randomly divided rats into five groups: sham, I/R, I/R+RA, I/R+Vehicle and I/R+RA+LY. Open-field, closed-field and Morris water maze tests were carried our separately to examine the anxiety and cognitive behavior of each group. Cresyl violet staining was used to examine the survival of hippocampal CA1 pyramidal neurons. The levels of p-Akt, p-JNK3 and cleaved caspase-3 in the hippocampus were also examined by Western blotting. Our results showed that administration of RA protected locomotive ability, relieved anxiety behavior and protected cognitive ability in cerebral I/R-injured rats. Additionally, RA significantly protected neurons in the hippocampal CA1 region against cerebral I/R-induced damage. Furthermore, RA increased the phosphorylation of Akt1, downregulated the phosphorylation of JNK3 and reduced the expression of cleaved caspase-3. Finally, the Akt inhibitor LY294002 reversed all the protective effects of RA, indicating that RA protects neurons in the hippocampal CA1 region from ischemic damage through the Akt/JNK3/caspase-3 signaling pathway.

PEG-b-(PELG-g-PLL) nanoparticles as TNF-α nanocarriers: potential cerebral ischemia/reperfusion injury therapeutic applications

Brain ischemia/reperfusion (I/R) injury (BI/RI) is a leading cause of death and disability worldwide. However, the outcome of pharmacotherapy for BI/RI remains unsatisfactory. Innovative approaches for enhancing drug sensitivity and recovering neuronal activity in BI/RI treatment are urgently needed. The purpose of this study was to evaluate the protective effects of tumor necrosis factor (TNF)-α-loaded poly(ethylene glycol)-b-(poly(ethylenediamine L-glutamate)-g-poly(L-lysine)) (TNF-α/PEG-b-(PELG-g-PLL)) nanoparticles on BI/RI. The particle size of PEG-b-(PELG-g-PLL) and the loading and release rates of TNF-α were determined. The nanoparticle cytotoxicity was evaluated in vitro using rat cortical neurons. Sprague Dawley rats were preconditioned with free TNF-α or TNF-α/PEG-b-(PELG-g-PLL) polyplexes and then subjected to 2 hours ischemia and 22 hours reperfusion. Brain edema was assessed using the brain edema ratio, and the antioxidative activity was assessed by measuring the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content in the brain tissue. We further estimated the inflammatory activity and apoptosis level by determining the levels of interleukin-4 (IL-4), IL-6, IL-8, IL-10, and nitric oxide (NO), as well as the expression of glial fibrillary acidic protein (GFAP), intercellular adhesion molecule-1 (ICAM-1), and cysteine aspartase-3 (caspase-3), in the brain tissue. We provide evidence that TNF-α preconditioning attenuated the oxidative stress injury, the inflammatory activity, and the apoptosis level in I/R-induced cerebral injury, while the application of block copolymer PEG-b-(PELG-g-PLL) as a potential TNF-α nanocarrier with sustained release significantly enhanced the bioavailability of TNF-α. We propose that the block copolymer PEG-b-(PELG-g-PLL) may function as a potent nanocarrier for augmenting BI/RI pharmacotherapy, with unprecedented clinical benefits. Further studies are needed to better clarify the underlying mechanisms.