NOD2 is involved in the inflammatory response after cerebral ischemia-reperfusion injury and triggers NADPH oxidase 2-derived reactive oxygen species

Innate Immune Signaling and Its Role in Metabolic and Cardiovascular Diseases

The innate immune system is an evolutionarily conserved system that senses and defends against infection and irritation. Innate immune signaling is a complex cascade that quickly recognizes infectious threats through multiple germline-encoded cell surface or cytoplasmic receptors and transmits signals for the deployment of proper countermeasures through adaptors, kinases, and transcription factors, resulting in the production of cytokines. As the first response of the innate immune system to pathogenic signals, inflammatory responses must be rapid and specific to establish a physical barrier against the spread of infection and must subsequently be terminated once the pathogens have been cleared. Long-lasting and low-grade chronic inflammation is a distinguishing feature of type 2 diabetes and cardiovascular diseases, which are currently major public health problems. Cardiometabolic stress-induced inflammatory responses activate innate immune signaling, which directly contributes to the development of cardiometabolic diseases. Additionally, although the innate immune elements are highly conserved in higher-order jawed vertebrates, lower-grade jawless vertebrates lack several transcription factors and inflammatory cytokine genes downstream of the Toll-like receptors (TLRs) and retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) pathways, suggesting that innate immune signaling components may additionally function in an immune-independent way. Notably, recent studies from our group and others have revealed that innate immune signaling can function as a vital regulator of cardiometabolic homeostasis independent of its immune function. Therefore, further investigation of innate immune signaling in cardiometabolic systems may facilitate the discovery of new strategies to manage the initiation and progression of cardiometabolic disorders, leading to better treatments for these diseases. In this review, we summarize the current progress in innate immune signaling studies and the regulatory function of innate immunity in cardiometabolic diseases. Notably, we highlight the immune-independent effects of innate immune signaling components on the development of cardiometabolic disorders.

Activation of the Omega-3 Fatty Acid Receptor GPR120 Protects against Focal Cerebral Ischemic Injury by Preventing Inflammation and Apoptosis in Mice

G protein-coupled receptor 120 (GPR120) has been shown to negatively regulate inflammation and apoptosis, but its role in cerebral ischemic injury remains unclear. Using an in vivo model of middle cerebral artery occlusion (MCAO) and an in vitro model of oxygen-glucose deprivation (OGD), we investigated the potential role and molecular mechanisms of GPR120 in focal cerebral ischemic injury. Increased GPR120 expression was observed in microglia and neurons following MCAO-induced ischemia in wild type C57BL/6 mice. Treatment with docosahexaenoic acid (DHA) inhibited OGD-induced inflammatory response in primary microglia and murine microglial BV2 cells, whereas silencing of GPR120 strongly exacerbated the inflammation induced by OGD and abolished the anti-inflammatory effects of DHA. Mechanistically, DHA inhibited OGD-induced inflammation through GPR120 interacting with β-arrestin2. In addition to its anti-inflammatory function, GPR120 also played a role in apoptosis as its knockdown impaired the antiapoptotic effect of DHA in OGD-induced rat pheochromocytoma (PC12) cells. Finally, using MCAO mouse model, we demonstrated that GPR120 activation protected against focal cerebral ischemic injury by preventing inflammation and apoptosis. Our study indicated that pharmacological targeting of GPR120 may provide a novel approach for the treatment of patients with ischemic stroke.

NOD2 promotes dopaminergic degeneration regulated by NADPH oxidase 2 in 6-hydroxydopamine model of Parkinson's disease

Background

In Parkinson’s disease (PD), loss of striatal dopaminergic (DA) terminals and degeneration of DA neurons in the substantia nigra (SN) are associated with inflammation. Nucleotide-binding oligomerization domain-containing protein (NOD)2, one of the first discovered NOD-like receptors, plays an important role in inflammation. However, the role of NOD2 has not been elucidated in PD.

Methods

NOD2 mRNA and protein expression in the SN and the striatum of C57BL/6 mice treated with 6-hydroxydopamine (6-OHDA) was measured. We next investigated the potential contribution of the NOD2-dependent pathway to 6-OHDA-induced DA degeneration using NOD2-deficient (NOD2^−/−) mice. Assays examining DA degeneration and inflammation include HPLC, Western blot, immunohistochemistry, TUNEL staining, and cytometric bead array. To further explore a possible link between NADPH oxidase 2 (NOX2) and NOD2 signaling in PD, microglia were transfected with shRNA specific to NOX2 in vitro and apocynin were given to mice subjected to 6-OHDA and muramyl dipeptide (MDP) striatal injection.

Results

The expression of NOD2 was upregulated in an experimental PD model induced by the neurotoxin 6-OHDA. NOD2 deficiency resulted in a protective effect against 6-OHDA-induced DA degeneration and neuronal death, which was associated with the attenuated inflammatory response. Moreover, silencing of NOX2 in microglia suppressed the expression of NOD2 and the inflammatory response induced by 6-OHDA and attenuated the toxicity of conditioned medium from 6-OHDA or MDP-stimulated microglia to neuronal cells. Furthermore, apocynin treatment inhibited NOD2 upregulation and DA degeneration in the SN of WT mice induced by 6-OHDA and MDP.

Conclusion

This study provides the direct evidence that NOD2 is related to 6-OHDA-induced DA degeneration through NOX2-mediated oxidative stress, indicating NOD2 is a novel innate immune signaling molecule participating in PD inflammatory response.

Electronic supplementary material

The online version of this article (10.1186/s12974-018-1289-z) contains supplementary material, which is available to authorized users.

NOD2 Expression in Streptococcus pneumoniae Meningitis and Its Influence on the Blood-Brain Barrier

Streptococcus pneumoniae meningitis is one of the most common disorders seen in clinical practice. It is believed that the brain tissue immune injury is caused by the expression of pattern-recognition receptors (PRR) which can further induce the release of other cytokines and inflammatory cascades. The aim of this study is to investigate the expression of nucleotide-binding oligomerization domain 2 (NOD2) and inflammatory factors in rat brain tissues infected with Streptococcus pneumoniae and its influence on the blood-brain barrier (BBB) permeability. Rats were given an intracranial injection of Streptococcus pneumoniae to construct the Streptococcus pneumoniae meningitis rat models. The expression change curves of NOD2 and inflammatory factors at different time points (0 h, 12 h, 24 h, 48 h, and 7 d) after Streptococcus pneumoniae were evaluated by enzyme-linked immunosorbent assay (ELISA). Western blotting analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were engaged to examine the expression of NOD2. Furthermore, the changing processes of pathological characteristics, nervous system score, cerebral oedema, and BBB permeability were observed. Our results showed that NOD2 expression began to increase in the 12 h after Streptococcus pneumoniae infection group, while the remaining inflammatory factors were not obviously increased. Meanwhile, the levels of NOD2, as well as inflammatory factors IL-1β, TNF-α, and IL-6 were markedly elevated in 24 h and 48 h infection groups, which were consistent with the increases in BBB permeability and BWC, and the positive expression of NOD2 in the infected rat brain tissues was observed using immunohistochemistry (IHC). This study suggests that NOD2 might be related to the activation of inflammation pathways and the damage to the blood-brain barrier. NOD2 and inflammatory factors have played vital roles in the pathogenesis of Streptococcus pneumoniae meningitis.

6'-O-Galloylpaeoniflorin Attenuates Cerebral Ischemia Reperfusion-Induced Neuroinflammation and Oxidative Stress via PI3K/Akt/Nrf2 Activation

6'-O-galloylpaeoniflorin (GPF), a galloylated derivative of paeoniflorin isolated from peony root, has been proven to possess antioxidant potential. In this present study, we revealed that GPF treatment exerted significant neuroprotection of PC12 cells following OGD, as evidenced by a reduction of oxidative stress, inflammatory response, cellular injury, and apoptosis in vitro. Furthermore, treatment with GPF increased the levels of phosphorylated Akt (p-Akt) and nuclear factor-erythroid 2-related factor 2 (Nrf2), as well as promoted Nrf2 translocation in PC12 cells, which could be inhibited by Ly294002, an inhibitor of phosphoinositide 3-kinase (PI3K). In addition, Nrf2 knockdown or Ly294002 treatment significantly attenuated the antioxidant, anti-inflammatory, and antiapoptotic activities of GPF in vitro. In vivo studies indicated that GPF treatment significantly reduced infarct volume and improved neurological deficits in rats subjected to CIRI, as well as decreased oxidative stress, inflammation, and apoptosis, which could be inhibited by administration of Ly294002. In conclusion, these results revealed that GPF possesses neuroprotective effects against oxidative stress, inflammation, and apoptosis after ischemia-reperfusion insult via activation of the PI3K/Akt/Nrf2 pathway.

NOD2 expression, DNA damage and oxido-inflammatory status in atopic bronchial asthma: Exploring their nexus to disease severity

BACKGROUND

Allergic asthma is a chronically relapsing inflammatory airway disease with a complex pathophysiology.

AIM

This study was undertaken to investigate the potential contribution of NOD2 signaling, proinflammatory cytokines, chitotriosidase (CHIT1) activity, oxidative stress and DNA damage to atopic asthma pathogenesis, as well as to explore their possible role as surrogate noninvasive biomarkers for monitoring asthma severity.

METHODS

Sixty patients with atopic bronchial asthma who were divided according to asthma severity into 40 mild-moderate, 20 severe atopic asthmatics, in addition to thirty age-matched healthy controls were enrolled in this study. NOD2 expression in PBMCs was assessed by quantitative real-time RT-PCR. DNA damage indices were assessed by alkaline comet assay. Serum IgE, IL-17, IL-8 and 3-Nitrotyrosine levels were estimated by ELISA. Serum CHIT1and GST activities, as well as MDA levels, were measured.

RESULTS

NOD2 mRNA relative expression levels were significantly decreased in atopic asthmatic cases relative to controls with lower values among severe atopic asthmatics. On the other hand, IL-17 and IL-8 serum levels, CHIT1 activity, DNA damage indices and oxidative stress markers were significantly increased in atopic asthmatic cases relative to controls with higher values among severe atopic asthmatics. The change in these parameters correlated significantly with the degree of decline in lung function.

CONCLUSION

The interplay between NOD2 signaling, proinflammatory cytokines, CHIT1 activity, heightened oxidative stress and DNA damage orchestrates allergic airway inflammation and thus contributing to the pathogenesis of atopic asthma. These parameters qualified for measurement as part of new noninvasive biomarker panels for monitoring asthma severity.

Neuroprotective Effect of Oxysophocarpine by Modulation of MAPK Pathway in Rat Hippocampal Neurons Subject to Oxygen-Glucose Deprivation and Reperfusion

Oxysophocarpine (OSC), an alkaloid isolated from Sophora flavescens Ait, has been traditionally used as a medicinal agent based on the observed pharmacological effects. In this study, the direct effect of OSC against neuronal injuries induced by oxygen and glucose deprivation (OGD) in neonatal rat primary-cultured hippocampal neurons and its mechanisms were investigated. Cultured hippocampal neurons, which were exposed to OGD for 2 h followed by a 24 h reoxygenation, were used as an in vitro model of ischemia and reperfusion. 2-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) assay were used to confirm neural damage and to further evaluate the protective effects of OSC. The concentration of intracellular-free calcium [Ca2+]i and mitochondrial membrane potential (MMP) were measured to determine the intracellular mechanisms and to further estimate the degree of neuronal damage. Changes in expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, p-ERK1/2, p-JNK1/2, and p-p38 MAPK were also observed in the in vitro model. It was shown that OSC (0.8, 2, or 5 µmol/L) significantly attenuated the increased absorbance of MTT, and the release of LDH manifests the neuronal damage by the OGD/R. Meanwhile, the pretreatment of the neurons during the reoxygenation period with OSC significantly increased MMP; it also inhibited [Ca2+]i the elevation in a dose-dependent manner. Furthermore, the pretreatment with OSC (0.8, 2, or 5 µmol/L) significantly down-regulated expressions of IL-1β, TNF-α, p-ERK1/2, p-JNK1/2, and p-p38 MAPK in neonatal rat primary-cultured hippocampal neurons induced by OGD/R injury. In conclusion, OSC displays a protective effect on OGD-injured hippocampal neurons by attenuating expression of inflammatory factors via down-regulated the MAPK signaling pathway.

A Mini-Review of the NADPH oxidases in Vascular Dementia: Correlation with NOXs and Risk Factors for VaD

Oxidative stress (OS) is one of the factors that cause dementia conditions such as Alzheimer’s disease and vascular dementia (VaD). In the pathogenesis of VaD, OS is associated with risk factors that include increased age, hypertension, and stroke. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs) are a molecular source of reactive oxygen species (ROS). According to recent studies, inhibition of NOX activity can reduce cognitive impairment in animal models of VaD. In this article, we review the evidence linking cognitive impairment with NOX-dependent OS, including the vascular NOX and non-vascular NOX systems, in VaD.

Inhibition of Rac1 ameliorates neuronal oxidative stress damage via reducing Bcl-2/Rac1 complex formation in mitochondria through PI3K/Akt/mTOR pathway

Although the neuroprotective effects of Rac1 inhibition have been reported in various cerebral ischemic models, the molecular mechanisms of action have not yet been fully elucidated. In this study, we investigated whether the inhibition of Rac1 provided neuroprotection in a diabetic rat model of focal cerebral ischemia and hyperglycemia-exposed PC-12 cells. Intracerebroventricular administration of lentivirus expressing the Rac1 small hairpin RNA (shRNA) and specific Rac1 inhibitor NSC23766 not only decreased the infarct volumes and improved neurologic deficits with a correlated significant activation of mitochondrial DNA specific proteins, such as OGG1 and POLG, but also elevated Bcl-2 S70 phosphorylation in mitochondria. Furthermore, the levels of p-PI3K, p-Akt and p-mTOR increased, while 8-OHdG, ROS production and Bcl-2/Rac1 complex formation in mitochondria reduced in both Rac1-shRNA- and NSC23766-treated rats. Moreover, to confirm our in vivo observations, inhibition of Rac1 activity by NSC23766 suppressed the interactions between Bcl-2 and Rac1 in the mitochondria of PC-12 cells cultured in high glucose conditions and protected PC-12 cells from high glucose-induced neurotoxicity. More importantly, these beneficial effects of Rac1 inhibition were abolished by PI3K inhibitor LY294002. In contrast to NSC23766 treatment, LY294002 had little effect on the decrement of p-PTEN level. Taken together, these findings revealed novel neuroprotective roles of Rac1 inhibition against cerebral ischemic reperfusion injury in vivo and high glucose-induced neurotoxicity in PC-12 cells in vitro, by reducing Bcl-2/Rac1 complex formation in mitochondria through the activation of PI3K/Akt/mTOR survival pathway.

Loss of NLRX1 Exacerbates Neural Tissue Damage and NF-κB Signaling following Brain Injury

Traumatic and nontraumatic brain injury results from severe disruptions in the cellular microenvironment leading to massive loss of neuronal populations and increased neuroinflammation. The progressive cascade of secondary events, including ischemia, inflammation, excitotoxicity, and free-radical release, contribute to neural tissue damage. NLRX1 is a member of the NLR family of pattern recognition receptors and is a potent negative regulator of several pathways that significantly modulate many of these events. Thus, we hypothesized that NLRX1 limits immune system signaling in the brain following trauma. To evaluate this hypothesis, we used Nlrx1^-/- mice in a controlled cortical impact (CCI) injury murine model of traumatic brain injury (TBI). In this article, we show that Nlrx1^-/- mice exhibited significantly larger brain lesions and increased motor deficits following CCI injury. Mechanistically, our data indicate that the NF-κB signaling cascade is significantly upregulated in Nlrx1^-/- animals. This upregulation is associated with increased microglia and macrophage populations in the cortical lesion. Using a mouse neuroblastoma cell line (N2A), we also found that NLRX1 significantly reduced apoptosis under hypoxic conditions. In human patients, we identify 15 NLRs that are significantly dysregulated, including significant downregulation of NLRX1 in brain injury following aneurysm. We further demonstrate a concurrent increase in NF-κB signaling that is correlated with aneurysm severity in these human subjects. Together, our data extend the function of NLRX1 beyond its currently characterized role in host-pathogen defense and identify this highly novel NLR as a significant modulator of brain injury progression.

Pre-treatment with spermine for acute cerebral ischemia/reperfusion injuries

Acute cerebral ischemia/reperfusion injury (ACIR) rat model was used to investigate the effect of spermine on oxidative stress and apoptosis. Sixty healthy and clean male Sprague-Dawley rats were randomly divided into 3 groups: The sham-operated group (n=12), the model group (n=12) and the experiment group (n=36). The experiment group was further divided into 3 subgroups: The SPE-10 group (n=12), the SPE-25 group (n=12) and the SPE-50 group (n=12). Rats in the experimental sub-groups SPE-10, SPE-25 and SPE-50 were injected with 10, 25 and 50 mg/kg of spermine, respectively, one week before the establishment of rat models. Rats in the sham-operated and model groups were injected with 0.9% NaCl solution. We evaluated the effect of spermine on malondialdehyde (MDA) level and superoxide dismutase (SOD) activity using ELISA kits. Bax and Bcl-2 levels were measured using western blot analysis. Our results showed that after spermine injection, MDA levels markedly decreased, while SOD activity increased significantly. The variations in MDA levels and SOD activity were dose (spermine)-dependent. Bax protein levels increased significantly, while Bcl-2 levels decreased significantly after the onset of ACIR injuries. After spermine injection, there was a significant decrease in Bax levels. Bcl-2 levels in these rats markedly increased. The observed decline in Bax levels and the increase in Bcl-2 levels in the experimental groups were dose-dependent. We concluded that spermine protected nerve tissues in rats with ACIR by decreasing the MDA level, increasing SOD activity and modifying the balance between Bax and Bcl-2 proteins.

Orientin Attenuates Cerebral Ischemia/Reperfusion Injury in Rat Model through the AQP-4 and TLR4/NF-κB/TNF-α Signaling Pathway

BACKGROUND

Orientin has been reported to have extensive pharmaceutical effects of antioxidant, anti-inflammatory, antithrombosis, antiapoptosis, and so on. In the present study, we tried to investigate the protective effects of orientin on cerebral ischemia-reperfusion (I/R) injury and explored the possible mechanisms.

METHODS

Middle cerebral artery occlusion rat model was established and then treated with low, middle, and high concentrations of orientin, respectively, with edaravone as a positive control. The treatment effect of orientin was evaluated by measuring the neurological deficit score, cerebral infarction, brain edema, oxidative stress, excitatory amino acids release, the expression levels of aquaporin-4 (AQP-4), and related inflammatory molecules using different methods including immunohistochemistry, enzyme-linked immunosorbent assay, real-time PCR, and western blot. Moreover, morphological and structural changes were also observed by hematoxylin-eosin staining and transmission electron microscope.

RESULTS

Orientin provided a significant reduction on neurological deficits, cerebral infarction, cerebral edema, oxidative damage, and neurotoxicity of excitatory amino acids compared to model group (P < .05) in a dose-dependent manner. In addition, orientin substantially downregulated AQP-4 and inflammatory factors expression (P < .05) and improved cell morphology and structure in rats following I/R injury.

CONCLUSION

Orientin was able to mediate noticeable protection against cerebral I/R injury through the attenuation of oxidative stress and neurotoxicity of amino acids and inhibiting the upregulation of AQP-4 and inflammatory cytokines.

Naringenin protects keratinocytes from oxidative stress injury via inhibition of the NOD2-mediated NF-κB pathway in pemphigus vulgaris

Naringenin is known to have anti-oxidative activity; however, the effect of naringenin on the progression of pemphigus vulgaris (PV) still remains unclear. This study aims to analyze the effect of naringenin on HaCaT cell apoptosis and oxidative damage under the treatment of PV serum. The results showed that PV serum significantly induced cell apoptosis compared with the control group; whereas, comparing with PV group, naringenin inhibited cell apoptosis. Moreover, PV serum increased the expression of bax and caspase-3, and decreased the expression of bcl-2; but naringenin significantly suppressed the expression of bax and caspase-3, induced the expression of bcl-2. Naringenin inhibited PV serum-induced disruption of cell-cell contacts. Naringenin also down-regulated the expression of Dsg1, Dsg3 and E-cadherin compared with the PV group. Additionally, naringenin noticeably decreased the PV serum-induced ROS production and alleviated PV serum induced the drop of mitochondrial membrane potential. Furthermore, naringenin increased the activity of SOD, GSH-Px and TAC under the treatment of PV serum. Naringenin also decreased the expression of NOD2, RIPK2 and NF-κB p-p65, but this effect could be reversed by muramyl dipeptide (MDP). In conclusion, these results suggested that naringenin protected keratinocytes from apoptosis and oxidative stress injury through inhibition of the NOD2-mediated NF-κB pathway.

Terlipressin protects intestinal epithelial cells against oxygen-glucose deprivation/re-oxygenation injury via the phosphatidylinositol 3-kinase pathway

Intestinal ischemia/reperfusion (I/R) injury is associated with a high morbidity and mortality. Vasopressin is administered to critically ill patients with potential intestinal I/R. However, the impacts of vasopressin on intestinal epithelia under ischemic/anoxic conditions remain unclear. The aim of the present study was to evaluate the effects of terlipressin, a highly selective vasopressin V1 receptor agonist, on oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damage in intestinal epithelial cells (IEC-6). IEC-6 cells were subjected to OGD for 4 h, followed by 4 h re-oxygenation. Terlipressin was incubated with cells for 4 h following OGD. Following OGD/R, IEC-6 cell viability, proliferation and apoptosis, as well as cell cycle dynamics, were assessed and the levels of tumor necrosis factor (TNF)-α and 15-F2t-isoprostane in the culture medium were measured. In addition, wortmannin, a specific phosphatidylinositol 3-kinase (PI3K) inhibitor, was administrated to investigate the mechanism of terlipressin action. The results demonstrated that IEC-6 cell viability and proliferation decreased, and cell apoptosis increased, following OGD/R. However, IEC-6 cell cycle dynamics did not significantly change 4 h after OGD. Incubation with 25 nM terlipressin significantly improved cell viability, proliferation and apoptosis. Furthermore, terlipressin inhibited the secretion of TNF-α and 15-F2t-isoprostane from IEC-6 cells following OGD/R. The aforementioned effects of terlipressin were completely abolished following the application of 2 µM wortmannin. Therefore, the current study demonstrated that terlipressin administration following OGD attenuates OGD/R-induced cell damage via the PI3K signaling pathway. These results may help physicians to better understand and more effectively use terlipressin in a clinical setting.

Neuroprotective Effects of Lycium barbarum Polysaccharide on Focal Cerebral Ischemic Injury in Mice

Increasing evidence demonstrates inflammation contributes to neuronal death following cerebral ischemia. Lycium barbarum polysaccharide (LBP) has been reported to prevent scopolamine-induced cognitive and memory deficits. We recently indicated that LBP exerts neuroprotective effect against focal cerebral ischemic injury in mice via attenuating the mitochondrial apoptosis pathway. The aim of this study was to investigate the neuroprotective effects of LBP against the behavioral dysfunction induced by focal cerebral ischemia injury in mice. Following 7 successive days of pretreatment with LBP (10, 20 and 40 mg/kg) and nimodipine (4 mg/kg) by intragastric gavage, mice were subjected to middle cerebral artery occlusion (MCAO). Following reperfusion, cerebral blood flows, the total power of the spontaneous EEG, and morphological changes were estimated. Learning and memory ability, and motor coordination were determined by Morris water maze task, rotarod and grip test. Western blot analysis, Real-Time fluorogenic PCR assays, and immunofluorescence staining were used to examine the expression of proinflammatory mediators and activation of microglia. The present study showed that LBP pretreatment significantly enhanced regional cortical blood flow and the total power of the spontaneous EEG, improved memory and motor coordination impairments, and inhibited over-activation of microglia and astrocytes after MCAO. Further study demonstrated LBP suppressed MCAO-induced activations of P65 NF-κB and P38 MAPK, and prevented up-regulations of proinflammatory mediators in hippocampus. Our data suggest that LBP can exert functional recovery of memory and motor coordination deficits and neuroprotective effect against cerebral ischemic injury in mice.

Impact of 17beta-estradiol and progesterone on inflammatory and apoptotic microRNA expression after ischemia in a rat model

17β-estradiol (E2) and progesterone (P) are neuroprotective factors in the brain preventing neuronal death under different injury paradigms. In previous studies, we demonstrated that both steroids dampen neuronal damage, improve local energy metabolism and attenuate pro-inflammatory responses. MicroRNAs (miRNAs) are small regulators of distinct target genes on the RNA level. Their expression patterns are misbalanced in several neurological disorders. To explore the regulatory mechanisms of steroid hormones on selected miRNAs and their validated targets in ischemia, we used the transient middle cerebral artery occlusion (tMCAO) model. 12-week old male rats were subjected to 2h tMCAO and expression patterns of miR-223, miR-200c, miR-375, miR-199 and miR-214 (all -3p) were determined. Using semi-quantitative real time PCR, we examined the role of E2 or P as regulatory factors for miRNAs and theirs target genes. Besides miR-375, all mentioned miRNAs showed a steady increase with a peak at 72h post tMCAO, whereas highest levels of miR-375 were detected at 12h post tMCAO. E2 or P selectively dampened miR-223 and miR-214 but further boosted miR-375 levels. With respect to the miR-223 regulated target genes NR2B and GRIA2 which both decreased after tMCAO, E2 and P application reversed this effect. Further, steroid treatment inhibited the hypoxia-induced increase of the miR-375 target genes Bcl-2 and RAD1. These findings provide new insights into the regulatory role of neuroprotection mediated by sex steroids in the brain. Both hormones are capable of influencing the expression of miRNAs which are relevant during neuropathological processes. Thereby, E2 and P indirectly control pro-apoptotic and -inflammatory gene translation and provide a mechanism to dampen explosive tissue damage.

The efficiency analysis of thrombolytic rt-PA combined with intravascular interventional therapy in patients with acute basilar artery occlusion

In order to further optimize the treatment strategy for the patients with acute basilar artery occlusion, we were dedicated to study the therapeutic effects and influential factors in the process of treated basilar artery occlusion with thrombolytic combined vascular interventional therapy. 75 patients with acute basilar artery occlusion treated with arterial thrombolytic therapy were analyzed retrospectively. In accordance with the discharge records of patients, their short-term curative effect with 24-hour treatment and 14-days treatment were evaluated. Our data showed that the survival condition of the patients with acute acute basilar artery occlusion were visibly improved by combination thrombolytic and interventional therapy. Moreover, their BI scores were remarkably improved, while NIHSS and mRS scores were evidently reduced. These data proved that our treatment strategy was able to improve the survival condition of patients with acute basilar artery occlusion. Furthermore, our data showed that coagulation related factors remarkably improved in the patients, when they treated by combination thrombolytic therapy with interventional therapy. In addition, our results suggested that the patients' bilateral Babinski(+), revascularization and coma symptom were closely related to their prognosis after treated the patients with combination thrombolytic and vascular interventional therapy, and the difference was statistically significant (p<0.05, p<0.05, p<0.05). Besides, our data also displayed that the with stent assisted angioplasty was significantly superior to the patients with balloon angioplasty, and the difference was statistically significant (p<0.05). Anyhow, combination thrombolytic with interventional therapy can effectively promote the prognosis of the patients with acute basilar artery occlusion. The coma symptom, bilateral Babinski(+), and revascularization in the patients with acute basilar artery occlusion have an appreciable impact on the patients' prognosis.

NADPH oxidase in brain injury and neurodegenerative disorders

Oxidative stress is a common denominator in the pathology of neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and multiple sclerosis, as well as in ischemic and traumatic brain injury. The brain is highly vulnerable to oxidative damage due to its high metabolic demand. However, therapies attempting to scavenge free radicals have shown little success. By shifting the focus to inhibit the generation of damaging free radicals, recent studies have identified NADPH oxidase as a major contributor to disease pathology. NADPH oxidase has the primary function to generate free radicals. In particular, there is growing evidence that the isoforms NOX1, NOX2, and NOX4 can be upregulated by a variety of neurodegenerative factors. The majority of recent studies have shown that genetic and pharmacological inhibition of NADPH oxidase enzymes are neuroprotective and able to reduce detrimental aspects of pathology following ischemic and traumatic brain injury, as well as in chronic neurodegenerative disorders. This review aims to summarize evidence supporting the role of NADPH oxidase in the pathology of these neurological disorders, explores pharmacological strategies of targeting this major oxidative stress pathway, and outlines obstacles that need to be overcome for successful translation of these therapies to the clinic.

Anti-Inflammatory Effects of Traditional Chinese Medicines against Ischemic Injury in In Vivo Models of Cerebral Ischemia

Inflammation plays a crucial role in the pathophysiology of acute ischemic stroke. In the ischemic cascade, resident microglia are rapidly activated in the brain parenchyma and subsequently trigger inflammatory mediator release, which facilitates leukocyte-endothelial cell interactions in inflammation. Activated leukocytes invade the endothelial cell junctions and destroy the blood-brain barrier integrity, leading to brain edema. Toll-like receptors (TLRs) stimulation in microglia/macrophages through the activation of intercellular signaling pathways secretes various proinflammatory cytokines and enzymes and then aggravates cerebral ischemic injury. The secreted cytokines activate the proinflammatory transcription factors, which subsequently regulate cytokine expression, leading to the amplification of the inflammatory response and exacerbation of the secondary brain injury. Traditional Chinese medicines (TCMs), including TCM-derived active compounds, Chinese herbs, and TCM formulations, exert neuroprotective effects against inflammatory responses by downregulating the following: ischemia-induced microglial activation, microglia/macrophage-mediated cytokine production, proinflammatory enzyme production, intercellular adhesion molecule-1, matrix metalloproteinases, TLR expression, and deleterious transcription factor activation. TCMs also aid in upregulating anti-inflammatory cytokine expression and neuroprotective transcription factor activation in the ischemic lesion in the inflammatory cascade during the acute phase of cerebral ischemia. Thus, TCMs exert potent anti-inflammatory properties in ischemic stroke and warrant further investigation.

Entropy-based divergent and convergent modular pattern reveals additive and synergistic anticerebral ischemia mechanisms

Module-based network analysis of diverse pharmacological mechanisms is critical to systematically understand combination therapies and disease outcomes. We first constructed drug-target ischemic networks in baicalin, jasminoidin, ursodeoxycholic acid, and their combinations baicalin and jasminoidin as well as jasminoidin and ursodeoxycholic acid groups and identified modules using the entropy-based clustering algorithm. The modules 11, 7, 4, 8 and 3 were identified as baicalin, jasminoidin, ursodeoxycholic acid, baicalin and jasminoidin and jasminoidin and ursodeoxycholic acid-emerged responsive modules, while 12, 8, 15, 17 and 9 were identified as disappeared responsive modules based on variation of topological similarity, respectively. No overlapping differential biological processes were enriched between baicalin and jasminoidin and jasminoidin and ursodeoxycholic acid pure emerged responsive modules, but two were enriched by their co-disappeared responsive modules including nucleotide-excision repair and epithelial structure maintenance. We found an additive effect of baicalin and jasminoidin in a divergent pattern and a synergistic effect of jasminoidin and ursodeoxycholic acid in a convergent pattern on "central hit strategy" of regulating inflammation against cerebral ischemia. The proposed module-based approach may provide us a holistic view to understand multiple pharmacological mechanisms associated with differential phenotypes from the standpoint of modular pharmacology.