The protective role of oxymatrine on neuronal cell apoptosis in the hemorrhagic rat brain

Oxymatrine combined with rapamycin to attenuate acute cardiac allograft rejection

Background and aim

Solid organ transplantation remains a life-saving therapeutic option for patients with end-stage organ dysfunction. Acute cellular rejection (ACR), dominated by dendritic cells (DCs) and CD4+ T cells, is a major cause of post-transplant mortality. Inhibiting DC maturation and directing the differentiation of CD4+ T cells toward immunosuppression are keys to inhibiting ACR. We propose that oxymatrine (OMT), a quinolizidine alkaloid, either alone or in combination with rapamycin (RAPA), attenuates ACR by inhibiting the mTOR-HIF-1α pathway.

Methods

Graft damage was assessed using haematoxylin and eosin staining. Intragraft CD11c+ and CD4+ cell infiltrations were detected using immunohistochemical staining. The proportions of mature DCs, T helper (Th) 1, Th17, and Treg cells in the spleen; donor-specific antibody (DSA) secretion in the serum; mTOR-HIF-1α expression in the grafts; and CD4+ cells and bone marrow-derived DCs (BMDCs) were evaluated using flow cytometry.

Results

OMT, either alone or in combination with RAPA, significantly alleviated pathological damage; decreased CD4+ and CD11c+ cell infiltration in cardiac allografts; reduced the proportion of mature DCs, Th1 and Th17 cells; increased the proportion of Tregs in recipient spleens; downregulated DSA production; and inhibited mTOR and HIF-1α expression in the grafts. OMT suppresses mTOR and HIF-1α expression in BMDCs and CD4+ T cells in vitro.

Conclusions

Our study suggests that OMT-based therapy can significantly attenuate acute cardiac allograft rejection by inhibiting DC maturation and CD4+ T cell responses. This process may be related to the inhibition of the mTOR-HIF-1α signaling pathway by OMT.

Therapeutic targeting of Ras/Raf/MAPK pathway by natural products: A systematic and mechanistic approach for neurodegeneration

BACKGROUND

Multiple dysregulated pathways are behind the pathogenesis of neurodegenerative diseases (NDDs); however, the crucial targets are still unknown. Oxidative stress, apoptosis, autophagy, and inflammation are the most dominant pathways that strongly influence neurodegeneration. In this way, targeting the Ras/Raf/mitogen-activated protein kinases (MAPKs) pathway appears to be a developing strategy for combating NDDs like Parkinson's disease, Alzheimer's disease, stroke, aging, and other NDDs. Accordingly, plant secondary metabolites have shown promising potentials for the simultaneous modulation of the Ras/Raf/MAPKs pathway and play an essential role in NDDs. MAPKs include p38 MAPK, extracellular signal-regulated kinase 1/2 (ERK 1/2), and c-Jun N-terminal kinase (JNK), which are important molecular players in neurodegeneration. Ras/Raf, which is located the upstream of MAPK pathway influences the initiation and progression of neurodegeneration and is regulated by natural products.

PURPOSE

Thus, the present study aimed to investigate the neuroprotective roles of plant- and marine-derived secondary metabolites against several NDDs through the modulation of the Ras/Raf/MAPK signaling pathway.

STUDY DESIGN AND METHODS

A systematic and comprehensive review was performed to highlight the modulatory roles of natural products on the Ras/Raf/MAPK signaling pathway in NDDs, according to the PRISMA guideline, using scholarly electronic databases, including PubMed, Scopus, and Web of Sciences. Associated reference lists were also searched for the literature review.

RESULTS

From a total of 1495 results, finally 107 articles were included in the present study. The results show that several natural compounds such as alkaloid, phenolic, terpenoids, and nanoformulation were shown to have modulatory effects on the Ras/Raf/MAPKs pathway.

CONCLUSION

Natural products are promising multi-targeted agents with on NDDs through Ras/Raf/MAPKs pathway. Nevertheless, additional and complementary studies are necessary to check its efficacy and potential side effects.

The construction of neurogenesis-related ceRNA network of ischemic stroke treated by oxymatrine

BACKGROUND

Known as a disease associated with high mortality, disability and a significant financial burden, ischemic stroke ranks as one of the three diseases threatening human health. Recent advances in omics technology created opportunities to uncover the mechanism in ischemic stroke occurrence and treatment. In this study, we aimed to construct the competitive endogenous RNA (ceRNA) networks of ischemic stroke treated by oxymatrine intervention.

METHOD

The middle cerebral artery occlusion (MCAO) mouse model of ischemic stroke was constructed, and oxymatrine was administered. Then RNA-Sequencing was performed and integrated analysis of mRNAs, lncRNAs and circRNAs was conducted to reveal the pharmacology of oxymatrine. Functional enrichment analysis was performed to explore the underlying mechanism of differentially expressed (DE) mRNAs. The protein-protein interaction (PPI) network of neurogenesis-related genes and long noncoding RNAs (lncRNAs)/circular RNAs (circRNAs) based ceRNA networks were constructed.

RESULTS

First, this study revealed the DE-mRNAs, DE-lncRNAs and DE-circRNAs between Oxymatrine treated group and the MCAO group. Then, the common 1231 DE-mRNAs, 32 DE-lncRNAs and 31 DE-circRNAs with opposite trends were identified. The Kyoto Encyclopedia of Genes and Genomes to identify the functional enrichment of 1231 DE-mRNAs were enriched in neurogenesis-related biological processes. Based on neurogenesis-related DE-mRNAs, the PPI network was constructed, and hub genes were identified based on centrality. Finally, both the lncRNA-based and circRNAs-based ceRNA networks were constructed.

CONCLUSION

In summary, this study identified novel coding and noncoding ischemic stroke targets of oxymatrine-treated MCAO. Most importantly, we identified lncRNAs and circRNAs candidates as potential oxymatrine targets and constructed the neurogenesis-related ceRNA networks.

Anti-Alphaviral Alkaloids: Focus on Some Isoquinolines, Indoles and Quinolizidines

The discovery and the development of safe and efficient therapeutics against arthritogenic alphaviruses (e.g., chikungunya virus) remain a continuous challenge. Alkaloids are structurally diverse and naturally occurring compounds in plants, with a wide range of biological activities including beneficial effects against prominent pathogenic viruses and inflammation. In this short review, we discuss the effects of some alkaloids of three biologically relevant structural classes (isoquinolines, indoles and quinolizidines). Based on various experimental models (viral infections and chronic diseases), we highlight the immunomodulatory effects of these alkaloids. The data established the capacity of these alkaloids to interfere in host antiviral and inflammatory responses through key components (antiviral interferon response, ROS production, inflammatory signaling pathways and pro- and anti-inflammatory cytokines production) also involved in alphavirus infection and resulting inflammation. Thus, these data may provide a convincing perspective of research for the use of alkaloids as immunomodulators against arthritogenic alphavirus infection and induced inflammation.

Traditional Chinese medicine use in the pathophysiological processes of intracerebral hemorrhage and comparison with conventional therapy

Intracerebral hemorrhage (ICH) refers to hemorrhage caused by non-traumatic vascular rupture in the brain parenchyma, which is characterized by acute onset, severe illness, and high mortality and disability. The influx of blood into the brain tissue after cerebrovascular rupture causes severe brain damage, including primary injury caused by persistent hemorrhage and secondary brain injury (SBI) induced by hematoma. The mechanism of brain injury is complicated and is a significant cause of disability after ICH. Therefore, it is essential to understand the mechanism of brain injury after ICH to develop drugs to prevent and treat ICH. Studies have confirmed that many traditional Chinese medicines (TCM) can reduce brain injury by improving neurotoxicity, inflammation, oxidative stress (OS), blood-brain barrier (BBB), apoptosis, and neurological dysfunction after ICH. Starting from the pathophysiological process of brain injury after ICH, this paper summarizes the mechanisms by which TCM improves cerebral injury after ICH and its comparison with conventional western medicine, so as to provide clues and a reference for the clinical application of TCM in the prevention and treatment of hemorrhagic stroke and further research and development of new drugs.

Cepharanthine Attenuates Early Brain Injury after Subarachnoid Hemorrhage in Mice via Inhibiting 15-Lipoxygenase-1-Mediated Microglia and Endothelial Cell Ferroptosis

Background

Ferroptosis is a newly identified form of programmed cell death caused by iron-dependent lipid peroxidation. Our study was designed to determine the expression patterns and role of 15-lipoxygenase-1 (ALOX15) in subarachnoid hemorrhage (SAH) and to investigate whether cepharanthine (CEP) can inhibit ferroptosis by inhibiting ALOX15 in specific cell types.

Methods

A mouse model of SAH was developed by the endovascular perforation method. bEend.3 endothelial cells and BV2 microglial cells as well as RSL3 and hemin were used to simulate SAH in vitro. Mice and cell lines were treated with CEP and a group of specific oxygenase inhibitors to explore the protection effect from ferroptosis. Lipid peroxidation staining with BODIPY 581/591 C11 and transmission electron microscopy were used to identify ferroptosis in vitro and in vivo.

Results

In the present study, the accumulation of lipid peroxide, a defect in the glutathione peroxidase 4 (GPx4)/glutathione (GSH) antioxidant system, highly expressed ALOX15 in microglia and endothelium, and ferroptotic changes in microglial mitochondria confirmed the occurrence of ferroptosis after SAH in vivo. Further, CEP was shown to inhibit ferroptosis and improve neurological function by downregulating the expression of ALOX15. During in vitro experiments, we investigated the important role ALOX15 in RSL3-induced endothelial ferroptosis. In addition, we found that M2-type microglia are more sensitive to RSL3-induced ferroptosis than M1-type microglia and that hemin probably induced ferroptosis in M2-type microglia by increasing ALOX15 levels and decreasing GPx4 levels. The effect of CEP treatment was also demonstrated in vitro.

Conclusions

In summary, to the best of our knowledge, this is the first study demonstrating that ferroptosis occurred in the microglia and endothelium after SAH, and this process was facilitated by increased ALOX15 levels. More importantly, treatment with CEP could inhibit ferroptosis through downregulating the expression of ALOX15.

Inhibition of PLA2G4E/cPLA2 promotes survival of random skin flaps by alleviating Lysosomal membrane permeabilization-Induced necroptosis

Necrosis that appears at the ischemic distal end of random-pattern skin flaps increases the pain and economic burden of patients. Necroptosis is thought to contribute to flap necrosis. Lysosomal membrane permeabilization (LMP) plays an indispensable role in the regulation of necroptosis. Nonetheless, the mechanisms by which lysosomal membranes become leaky and the relationship between necroptosis and lysosomes are still unclear in ischemic flaps. Based on Western blotting, immunofluorescence, enzyme-linked immunosorbent assay, and liquid chromatography-mass spectrometry (LC-MS) analysis results, we found that LMP was presented in the ischemic distal portion of random-pattern skin flaps, which leads to disruption of lysosomal function and macroautophagic/autophagic flux, increased necroptosis, and aggravated necrosis of the ischemic flaps. Moreover, bioinformatics analysis of the LC-MS results enabled us to focus on the role of PLA2G4E/cPLA2 (phospholipase A2, group IVE) in LMP of the ischemic flaps. In vivo inhibition of PLA2G4E with an adeno-associated virus vector attenuated LMP and necroptosis, and promoted flap survival. In addition, microRNA-seq helped us determine that Mir504-5p was differentially expressed in ischemic flaps. A string of in vitro and in vivo tests was employed to verify the inhibitory effect of Mir504-5p on PLA2G4E, LMP and necroptosis. Finally, we concluded that the inhibition of PLA2G4E by Mir504-5p reduced LMP-induced necroptosis, thereby promoting the survival of random-pattern skin flaps.

The Effect of Induced Diabetes Mellitus on the Cerebellar Cortex of Adult Male Rat and the Possible Protective Role of Oxymatrine: A Histological, Immunohistochemical and Biochemical Study

Diabetes mellitus (DM) represents a widespread metabolic disease with a well-known neurotoxicity in both central and peripheral nervous systems. Oxymatrine is a traditional Chinese herbal medicine that has various pharmacological activities including: anti-oxidant, anti-apoptotic and anti-inflammatory potentials. The present work aimed to study the impact of diabetes mellitus on the cerebellar cortex of adult male albino rat and to evaluate the potential protective role of oxymatrine. Fifty-five adult male rats were randomly divided into three groups: group I served as control, group II was given oxymatrine (80 mg/kg/day) orally for 8 weeks and group III was given a single dose of streptozotocin (50 mg/kg) intaperitoneally to induce diabetes. Then diabetic rats were subdivided into two subgroups: subgroup IIIa that received no additional treatment and subgroup IIIb that received oxymatrine similar to group II. The diabetic group revealed numerous changes in the Purkinje cell layer in the form of multilayer arrangement of Purkinje cells, shrunken cells with deeply stained nuclei as well as focal loss of the Purkinje cells. A significant increment in glial fibrillary acidic protein (GFAP) and synaptophysin expression were reported in immunohistochemistry compared with the control group. Transmission electron microscopy showed irregularity and splitting of myelin sheaths in the molecular layer, dark shrunken Purkinje cells with ill-defined nuclei, dilated Golgi saccules and dense granule cells with irregular nuclear outlines in the granular layer. In contrast, these changes were less evident in diabetic rats that received oxymatrine. In conclusion, Oxymatrine could protect the cerebellar cortex against changes induced by DM.

Drug repurposing for COVID-19 via knowledge graph completion

OBJECTIVE

To discover candidate drugs to repurpose for COVID-19 using literature-derived knowledge and knowledge graph completion methods.

METHODS

We propose a novel, integrative, and neural network-based literature-based discovery (LBD) approach to identify drug candidates from PubMed and other COVID-19-focused research literature. Our approach relies on semantic triples extracted using SemRep (via SemMedDB). We identified an informative and accurate subset of semantic triples using filtering rules and an accuracy classifier developed on a BERT variant. We used this subset to construct a knowledge graph, and applied five state-of-the-art, neural knowledge graph completion algorithms (i.e., TransE, RotatE, DistMult, ComplEx, and STELP) to predict drug repurposing candidates. The models were trained and assessed using a time slicing approach and the predicted drugs were compared with a list of drugs reported in the literature and evaluated in clinical trials. These models were complemented by a discovery pattern-based approach.

RESULTS

Accuracy classifier based on PubMedBERT achieved the best performance (F1 = 0.854) in identifying accurate semantic predications. Among five knowledge graph completion models, TransE outperformed others (MR = 0.923, Hits@1 = 0.417). Some known drugs linked to COVID-19 in the literature were identified, as well as others that have not yet been studied. Discovery patterns enabled identification of additional candidate drugs and generation of plausible hypotheses regarding the links between the candidate drugs and COVID-19. Among them, five highly ranked and novel drugs (i.e., paclitaxel, SB 203580, alpha 2-antiplasmin, metoclopramide, and oxymatrine) and the mechanistic explanations for their potential use are further discussed.

CONCLUSION

We showed that a LBD approach can be feasible not only for discovering drug candidates for COVID-19, but also for generating mechanistic explanations. Our approach can be generalized to other diseases as well as to other clinical questions. Source code and data are available at https://github.com/kilicogluh/lbd-covid.

Protective effect of Oxymatrine against acute spinal cord injury in rats via modulating oxidative stress, inflammation and apoptosis

The present study was performed to examine the effect of oxymatrine (OMT) on motor functions and histopathologic changes after spinal cord injury and the mechanism underlying its neuroprotective effects. Results suggested that, OMT causes regain of lost motor function near to normal via attenuating oxidative stress, inflammatory response and cellular apoptosis. These observations were further supported by histological examination of spinal cord of rats. It also showed to regulate pro-inflammatory cytokines, Bcl2 family proteins and reduces the level of toll like receptor (TLR-4) and nuclear factor-kappa B (NF-ĸB) in concentration dependent manner. The mitogen-activated protein kinase (MAPK) pathway was also regulated by OMT after SCI. It has been suggested that, OMT promotes the recovery of motor function after SCI in rats via multiple mechanism, and this effect may be related to its anti-oxidant, anti-inflammatory and anti-apoptotic effects.

The pharmacology of the genus Sophora (Fabaceae): An updated review

BACKGROUND

The genus Sophora (Fabaceae) represents one of the important medicinal plant genera regarding its chemical constituents and outstanding pharmacological activities.

PURPOSE

In this review, we surveyed the latest findings on the bioactivities of different Sophora extracts and isolated phytochemicals during the past 8 years (2011-2019) updating the latest review article in 2011. The aim of this review is to focus on the molecular pharmacology of Sophora species to provide the rationale basis for the development of novel drugs.

RESULTS

Sophora and its bioactive compounds possess outstanding pharmacological properties, especially as anticancer and anti-inflammatory drugs, in addition to its antioxidant, antibacterial, antifungal and antiviral properties.

CONCLUSION

Based on their use in traditional medicine, Sophora species exert a plethora of cellular and molecular activities, which render them as attractive candidates for rationale drug development. Randomized, placebo-controlled clinical trials are required for further integration of Sophora-based phototherapies into conventional medicine.

Herbal Compounds Play a Role in Neuroprotection through the Inhibition of Microglial Activation

Since microglia possess both neuroprotective and neurotoxic potential, they play a crucial role in the central nervous system (CNS). Excessive microglial activation induces inflammation-mediated neuronal damage and degeneration. At present, numerous herbal compounds are able to suppress neurotoxicity via inhibiting microglial activation. Therefore, many researchers focus on pharmacological inhibitors of microglial activation to ameliorate neurodegenerative disorders. Further work should concentrate on the exploration of new herbal compounds, which characteristically inhibit microglial neurotoxicity, rather than modulating neuroprotection alone. In this review, we summarize these herbal compounds, which in the past several years have been shown to exert potential neuroprotective activity by inhibiting microglial activation. The therapeutic targets and pharmacological mechanisms of these compounds have also been discussed.

Oxymatrine attenuates lipopolysaccharide-induced acute lung injury by activating the epithelial sodium channel and suppressing the JNK signaling pathway

The epithelial sodium channel (ENaC) and mitogen-activated protein kinase (MAPK) pathway have been reported to be associated with the progression of acute lung injury (ALI). Oxymatrine (OMT) alone or combined with other drugs can ameliorate paraquat- or oleic acid-induced lung injury. However, the effect of OMT on lipopolysaccharide (LPS)-induced ALI remains unknown. The aim of the present study was to evaluate whether OMT can attenuate LPS-induced ALI through regulation of the ENaC and MAPK pathway using an ALI mouse model. Histological assessment of the lung and inflammatory cell counts in bronchoalveolar lavage fluid (BALF) were performed by H&E and Wright-Giemsa staining. The lung wet/dry (W/D) weight ratio and the levels of tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), ENaC subunits, and the MAPK pathway members were determined. Isolated type II rat alveolar epithelial cells were incubated with OMT 30 min before LPS stimulation to investigate the activation of ENaC and the MAPK pathway. The results showed that OMT remarkably alleviated histopathologic changes in lung and pulmonary edema, reduced inflammatory cell counts in BALF, and decreased TNF-α and CRP levels in a dose-dependent manner. OMT significantly increased the three subunits of ENaC proteins in vivo and in vitro, while it decreased p-ERK/ERK, p-p38/p38, and p-JNK/JNK ratios in vivo. However, only the JNK pathway was markedly inhibited in vitro following pretreatment with OMT. Collectively, the results suggested that OMT might alleviate LPS-induced ALI by elevating ENaC proteins and inhibiting the JNK signaling pathway.

The regulatory effect of oxymatrine on the TLR4/MyD88/NF-κB signaling pathway in lipopolysaccharide-induced MS1 cells

BACKGROUND

Oxymatrine (OM), a major quinolizidine alkaloid extracted from the roots of Sophora flavescens, has been proved to regulate a variety of signaling pathways to produce a wide range of pharmacological effects.

OBJECTIVES

The regulatory effects of OM on the TLR4/MyD88/NF-κB signaling pathway under the stimulation of lipopolysaccharide (LPS) in MS1 cells were explored to illuminate the potential anti-inflammatory mechanism of OM for pancreatitis treatment.

METHODS

The signaling molecules related to the TLR4/MyD88/NF-κB pathway in MS1 cells were detected by Western blotting under different conditions, including OM pretreatment and LPS stimulation. The mRNA expression levels of TLR4, MyD88, NF-κB p65 and IκBα were detected by real-time PCR. The NF-κB p65 nuclear translocation in MS1 cells was measured by immunofluorescence, and the pro-inflammatory cytokine of IL-1β was detected by ELISA.

RESULTS

Increased levels of TLR4, MyD88 and NF-κB p65, induced by LPS stimulation, were significantly inhibited by OM pretreatment in MS1 cells. The decreased protein, but not mRNA, level of IκBα induced by LPS stimulation was increased by OM pretreatment. Meanwhile, LPS induced NF-κB p65 protein translocation to the nucleus as well as LPS increased expression of IL-1β were also inhibited by OM pretreatment.

CONCLUSION

Inhibitory effects of OM on molecules related to the TLR4/MyD88/NF-κB signaling pathway in pancreatic microvascular endothelial cells can alleviate inflammatory responses.

Sevoflurane Postconditioning-Induced Anti-Inflammation via Inhibition of the Toll-Like Receptor-4/Nuclear Factor Kappa B Pathway Contributes to Neuroprotection against Transient Global Cerebral Ischemia in Rats

The anti-inflammatory actions of sevoflurane postconditioning are suggested as an important mechanism of sevoflurane postconditioning-induced neuroprotection against cerebral ischemia. Here, we determined whether the anti-inflammatory effects of sevoflurane postconditioning were mediated via inhibition of the toll-like receptor (TLR)-4/nuclear factor kappa B (NF-κB) pathway after global transient cerebral ischemia in rats. Forty-five rats were randomly assigned to five groups as follows: (1) control (10 min of ischemia, n = 10); (2) sevoflurane postconditioning (two periods of sevoflurane inhalation after ischemia for 10 min with a wash period of 10 min, n = 10); (3) resatorvid (intraperitoneal injection of a selective TLR-4 antagonist (3 mg/kg) 30 min before ischemia, n = 10); (4) sevoflurane postconditioning plus resatorvid (n = 10), and sham (n = 5). The numbers of necrotic and apoptotic cells in the hippocampal CA1 region, the expression levels of TLR-4, NF-κB, cleaved caspase-3, and tumor necrosis factor alpha (TNF-α) in the anterior part of each brain, and the serum levels of TNF-α, interleukin 6 (IL-6), and interleukin 1 beta (IL-1β) were assessed 1 day after ischemia. The necrotic cell counts and expression levels of TLR-4, NF-κB, caspase-3, and TNF-α in brain tissue as well as serum levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) were significantly higher in the control group than in the other groups. Our findings suggest that the anti-inflammatory actions of sevoflurane postconditioning via inactivation of the TLR-4/NF-κB pathway and subsequent reduction in pro-inflammatory cytokine production, in part, contribute to sevoflurane postconditioning-induced neuroprotection after global transient cerebral ischemia in rats.

Oxymatrine attenuated isoproterenol-induced heart failure in rats via regulation of COX-2/PGI2 pathway

Oxymatrine (OMT) is an active constituent of traditional Chinese herb Sophora japonica Ait which has been shown to exert potent anti-inflammatory,anti-oxidant and anti-fibrosis properties. Our previous studies have demonstrated that OMT has protective effects on isoproterenol-induced heart failure in rats through regulation of DDAH/ADMA metabolism pathway.In this study,we further investigated whether OMT could attenuate isoproterenol-induced heart failure through the regulation of COX-2/PGI₂ pathway. Heart failure was induced in Sprague-Dawley rats by 5mg/kg isoproterenol subcutaneous injection for 7days. The rats were maintained on normal diet and randomly divided into five groups: control, isoproterenol, isoproterenol with OMT (50, 100mg/kg), and OMT alone groups (n=12 in each group). Serum brain natruretic peptide (BNP, a heart failure biomarker), histopathological variables, expression of Cytosolic phospholipase A₂ (cPLA₂), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and Prostacyclin synthase (PGIS) were analysed. Administration of OMT significantly reduced the increased BNP in plasm of isoproterenol-induced rats, attenuated cardiac fibrosis,suppressed overexpression of myocardial COX-1 expression, up-regulated COX-2 and PGIS expression, but had no effects on isoproterenol-induced elevated protein cPLA₂. And compared with control group, any indexes in sham rats treated with OMT (100mg/kg) alone were unaltered. These results demonstrated that OMT has cardioprotective effects on isoproterenol-induced heart failure in rats by regulating COX-2/PGI₂ pathway.

Reduced apurinic/apyrimidinic endonuclease activity enhances the antitumor activity of oxymatrine in lung cancer cells

Lung cancer is the leading cause of cancer-related deaths worldwide and is associated with a very poor outcome. Oxymatrine exerts antitumor effects by inducing apoptosis and inhibiting the proliferation of different cancer cells; however, the anticancer effects and mechanism of action of oxymatrine have not been evaluated sufficiently in human lung cancer cells. Thus, the present study aimed to investigate the anticancer effects of oxymatrine in human lung cancer cells and identify the molecular mechanisms underlying these effects. MTT assays demonstrated that oxymatrine significantly inhibited the proliferation of A549 and H1299 cells in a time- and dose-dependent manner. In addition, flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assays suggested that oxymatrine treatment may induce lung cancer cell apoptosis in a dose-dependent manner. Furthermore, we detected that oxymatrine induced a significant increase in DNA damage and the expression of PARP and phosphorylated H2AX, and a significant decrease in that of nuclear APE1 and AP endonuclease activity in A549 cells. APE1 knockdown cells (APE1shRNA) plus oxymatrine treatment reduced cells proliferation and induced apoptosis more seriously than control shRNA cells. This appeared to be a consequence of an increase in the number of apurinic/apyrimidinic (AP) sites, DNA damage, PARP and H2AX phosphorylation, which together resulted in the induction of apoptosis. In contrast, the sensitizing effects of APE1 overexpression plus oxymatrine treatment did not occur in APEOE cells. These findings reveal a potential mechanism of action for oxymatrine-induced apoptosis and suggest that oxymatrine is a promising potential therapeutic agent for the treatment of lung cancer.

Oxymatrine inhibits microglia activation via HSP60-TLR4 signaling

Oxymatrine (OMT) is an alkaloid extracted from Sophora flavescens, which has broad anti-inflammatory, antitumor and immunosuppressant actions. However, the underlying molecular mechanisms have remained elusive. Heat shock protein 60 (HSP60) has recently been shown to have an important role in autoimmune reactions. The present study aimed to investigate whether OMT exerts its anti-inflammatory effects by inhibiting microglial activation and examined the role of HSP60 in this process. Western blot analysis and ELISA showed that OMT decreased the expression and release of HSP60 by LPS-activated BV2 cells. The expression of heat shock factor 1, the transcription factor of HSP60, was also suppressed by OMT. Extracellular HSP60 has been previously indicated to induce microglial apoptosis through the Toll-like receptor (TLR)-4 pathway. Flow cytometric analysis demonstrated that LPS treatment induced apoptosis of BV2 cells, which was inhibited by OMT in parallel with inhibition of LPS-induced expression of TLR-4. Furthermore, OMT was shown to suppress the levels of myeloid differentiation factor (MYD)88, nuclear factor (NF)-κB, caspase-3, inducible nitric oxide synthase, tumor necrosis factor-α, interleukin (IL)-1β and IL-6. In light of these results, it was concluded that OMT may exert its neuroprotective effects via HSP60/TLR-4/MYD88/NF-κB signaling pathways to inhibit microglial activation. OMT may therefore offer substantial therapeutic potential for treating neurodegenerative diseases associated with microglial activation.

OTUB1 attenuates neuronal apoptosis after intracerebral hemorrhage

OTUB1 is a member of deubiquitinating enzymes, which was shown as a proteasome-associated DUB to be involved in the proteins Ub-dependent degradation. Previous studies have indicated that OTUB1 was expressed in brain. But its distribution and function in the brain remain unclear. In this study, we explored the roles of OTUB1 protein in the pathophysiology of intracerebral hemorrhage (ICH). From the results of Western blot, immunohistochemistry, and immunofluorescence, we found an obvious up-regulation of OTUB1 in neurons adjacent to the hematoma after ICH. Furthermore, we also found that the increase of OTUB1 expression was accompanied by the enhanced expression of Bax and active caspase-3, and decreased expression of Bcl-2 in the pathological process of rat ICH. What's more, our in vitro study, using OTUB1 RNA interference in PC12 cells, suggested that OTUB1 might exert its anti-apoptotic function in neuronal apoptosis. Therefore, OTUB1 may play a role in protecting the brain from secondary damage following ICH.

The Anti-Inflammatory Effects of Blueberries in an Animal Model of Post-Traumatic Stress Disorder (PTSD)

Post-traumatic stress disorder (PTSD) is a trauma and stressor-related disorder that results in a prolonged stress response. It is associated with increased oxidative stress and inflammation in the prefrontal cortex (PFC) and hippocampus (HC). The only approved therapy for PTSD is selective serotonin re-uptake inhibitors (SSRIs), but their efficacy is marginal. Recently, we demonstrated that over-production of norepinephrine (NE) as the possible reason for the lack of efficacy of SSRIs. Hence, there is a need for novel therapeutic approaches for the treatment of PTSD. In this study, we investigated the anti-inflammatory role of blueberries in modulating inflammatory markers and neurotransmitter levels in PTSD. Rats were fed either a blueberry enriched (2%) or a control diet. Rats were exposed to cats for one hour on days 1 and 11 of a 31-day schedule to simulate traumatic conditions. The rats were also subjected to psychosocial stress via daily cage cohort changes. At the end of the study, the rats were euthanized and the PFC and HC were isolated. Monoamines were measured by high-performance liquid chromatography. Reactive oxygen species (ROS), gene and protein expression levels of inflammatory cytokines were also measured. In our PTSD model, NE levels were increased and 5-HT levels were decreased when compared to control. In contrast, a blueberry enriched diet increased 5-HT without affecting NE levels. The rate limiting enzymes tyrosine hydroxylase and tryptophan hydroxylase were also studied and they confirmed our findings. The enhanced levels free radicals, gene and protein expression of inflammatory cytokines seen in the PTSD group were normalized with a blueberry enriched diet. Decreased anxiety in this group was shown by improved performance on the elevated plus-maze. These findings indicate blueberries can attenuate oxidative stress and inflammation and restore neurotransmitter imbalances in a rat model of PTSD.

Potential Signaling Pathways Involved in the Clinical Application of Oxymatrine

Oxymatrine, an alkaloid component extracted from the roots of Sophora species, has been shown to have antiinflammatory, antifibrosis, and antitumor effects and the ability to protect against myocardial damage, etc. The potential signaling pathways involved in the clinical application of oxymatrine might include the TGF-β/Smad, toll-like receptor 4/nuclear factor kappa-light-chain-enhancer of activated B cells, toll-like receptor9/TRAF6, Janus kinase/signal transduction and activator of transcription, phosphatidylinositol-3 kinase/Akt, delta-opioid receptor-arrestinl-Bcl-2, CD40, epidermal growth factor receptor, nuclear factor erythroid-2-related factor 2/heme oxygenase-1 signaling pathways, and dimethylarginine dimethylaminohydrolase/asymmetric dimethylarginine metabolism pathway. In this review, we summarize the recent investigations of the signaling pathways related to oxymatrine to provide clues and references for further studies on its clinical application. Copyright © 2016 John Wiley & Sons, Ltd.

Innate immune receptor Toll-like receptor 4 signalling in neuropsychiatric diseases

The innate immunity is a stereotyped first line of defense against pathogens and unspecified damage signals. One of main actors of innate immunity are the Toll-like receptors (TLRs), and one of the better characterized members of this family is TLR-4, that it is mainly activated by Gram-negative bacteria lipopolysaccharide. In brain, TLR-4 organizes innate immune responses against infections or cellular damage, but also possesses other physiological functions. In the last years, some evidences suggest a role of TLR-4 in stress and stress-related neuropsychiatric diseases. Peripheral and brain TLR-4 activation triggers sickness behavior, and its expression is a risk factor of depression. Some elements of the TLR-4 signaling pathway are up-regulated in peripheral samples and brain post-mortem tissue from depressed and suicidal patients. The "leaky gut" hypothesis of neuropsychiatric diseases is based on the existence of an increase of the intestinal permeability which results in bacterial translocation able to activate TLR-4. Enhanced peripheral TLR-4 expression/activity has been described in subjects diagnosed with schizophrenia, bipolar disorder and in autistic children. A role for TLR-4 in drugs abuse has been also proposed. The therapeutic potential of pharmacological/genetic modulation of TLRs signaling pathways in neuropsychiatry is promising, but a great preclinical/clinical scientific effort is still needed.

Oxymatrine and cancer therapy

Oxymatrine is a kind of alkaloid extracted from traditional Chinese herb Sophora flavescens Ait. It has been proved to exert various biological activities such as anti-angiogenesis, proliferation-inhibiting, apoptosis-promoting, analgesic-strengthening, and anti-metastasis. The biological activities are related with inhibition of angiogenesis-associated factors, regulation of related signaling pathway and protein expression, synergistic effects with chemotherapy drug, cell cycle arrest and inhibition of voltage-activated K+ channel. In this review, we summarize the recent investigations of oxymatrine in cancer therapy so as to provide references for further study and clinical therapy.

Effects of oxymatrine on the apoptosis and proliferation of gallbladder cancer cells

Gallbladder carcinoma is the most common malignancy of the biliary tract and is associated with a very poor outcome. The aim of the present study was to investigate the effects of oxymatrine (OM) on gallbladder cancer cells and the possible mechanism of its effects. The effects of OM on the proliferation of gallbladder cancer cells (GBC-SD and SGC-996) were investigated using cell counting kit-8 and colony formation assays. Annexin V/propidium iodide double staining was performed to investigate whether OM could induce apoptosis in gallbladder cancer cells. The mitochondrial membrane potential (ΔΨm) and expression of apoptosis-associated proteins were evaluated to identify a mechanism for the effects of OM. In addition, the RNA expression of relevant genes was measured by qRT-PCR using the SYBR Green method. Finally, a subcutaneous implantation model was used to verify the effects of OM on tumor growth in vivo. We found that OM inhibited the proliferation of gallbladder cancer cells. In addition, Annexin V/propidium iodide double staining showed that OM induced apoptosis after 48 h and the ΔΨm decreased in a dose-dependent manner after OM treatment. Moreover, the activation of caspase-3 and Bax and downregulation of Bcl-2 and nuclear factor κB were observed in OM-treated cells. Finally, OM potently inhibited in-vivo tumor growth following subcutaneous inoculation of SGC-996 cells in nude mice. In conclusion, OM treatment reduced proliferation and induced apoptosis in gallbladder cancer cells, which suggests that this drug may serve as a novel candidate for adjuvant treatment in patients with gallbladder cancer.

Oxymatrine inhibits the proliferation of prostate cancer cells in vitro and in vivo

Oxymatrine is an alkaloid, which is derived from the traditional Chinese herb, Sophora flavescens Aiton. Oxymatrine has been shown to exhibit anti-inflammatory, antiviral, and anticancer properties. The present study aimed to investigate the anticancer effects of oxymatrine in human prostate cancer cells, and the underlying molecular mechanisms of these effects. An MTT assay demonstrated that oxymatrine significantly inhibited the proliferation of prostate cancer cells in a time- and dose-dependent manner. In addition, flow cytometry and a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay suggested that oxymatrine treatment may induce prostate cancer cell apoptosis in a dose-dependent manner. Furthermore, western blot analysis demonstrated a significant increase in the expression of p53 and bax, and a significant decrease in that of Bcl-2, in prostrate cancer cells in a dose-dependent manner. In vivo analysis demonstrated that oxymatrine inhibited tumor growth following subcutaneous inoculation of prostate cancer cells into nude mice. The results of the present study suggested that the antitumor properties of oxymatrine, may be associated with the inhibition of cell proliferation, and induction of apoptosis, via the regulation of apoptosis-associated gene expression. Therefore, the results may provide a novel approach for the development of prostate cancer therapy using oxymatrine, which is derived from the traditional Chinese herb, Sophora flavescens.

Natural alkaloids: basic aspects, biological roles, and future perspectives

Natural products have gained popularity worldwide for promoting healthcare, as well as disease prevention. Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation, antibacterial, antiviral, insecticidal, and antimetastatic effects on various types of cancers both in vitro and in vivo. This paper focuses on the naturally-derived alkaloids such as berberine, matrine, piperine, fritillarine, and rhynchophylline, etc., and summarizes the action mechanisms of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as drugs is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made. Following this, it is hoped that as a result of this review, there will be a greater awareness of the excellent promise that natural alkaloids show for use in the therapy of diseases.

Oxymatrine attenuates diabetes-associated cognitive deficits in rats

AIM

Oxymatrine (OMT) is the major quinolizidine alkaloid extracted from the root of Sophora flavescens Ait (the Chinese herb Kushen) and exhibits diverse pharmacological actions. In this work we investigated the effects of OMT on diabetes-associated cognitive decline (DACD) in a rat model of diabetes and explored the mechanisms of action.

METHODS

Male Wistar rats were injected with streptozotocin (65 mg/kg, ip) once to induce diabetes. The rats were then treated with vehicle or OMT (60 or 120 mg/kg per day, ip) for 7 weeks. Memory function was assessed using Morris water maze test. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), NF-κB p65 unit, TNF-α, IL-1β and caspase-3 in the cerebral cortex and hippocampus were quantified.

RESULTS

The diabetic rats exhibited markedly reduced body weight and increased plasma glucose level. The memory function of the rats assessed using Morris water maze test showed significant reduction in the percentage of time spent in the target quadrant and the number of times crossing the platform, coupled with markedly prolongation of escape latency and mean path length. Moreover, the rats showed oxidative stress (significantly increased MDA, decreased SOD and reduced GSH levels), as well as significant increases of NF-κB p65 unit, TNF-α, IL-1β and caspase-3 levels in the cerebral cortex and hippocampus. Chronic treatment with OMT dose-dependently reversed these behavioral, biochemical and molecular changes in the diabetic rats. However, the swimming speed had no significant difference among the control, diabetic and OMT-treated diabetic rats.

CONCLUSION

Chronic treatment with OMT alleviates diabetes-associated cognitive decline in rats, which is associated with oxidative stress, inflammation and apoptotic cascades.

Inflammation in intracerebral hemorrhage: from mechanisms to clinical translation

Intracerebral hemorrhage (ICH) accounts for 10-15% of all strokes and is associated with high mortality and morbidity. Currently, no effective medical treatment is available to improve functional outcomes in patients with ICH. Potential therapies targeting secondary brain injury are arousing a great deal of interest in translational studies. Increasing evidence has shown that inflammation is the key contributor of ICH-induced secondary brain injury. Inflammation progresses in response to various stimuli produced after ICH. Hematoma components initiate inflammatory signaling via activation of microglia, subsequently releasing proinflammatory cytokines and chemokines to attract peripheral inflammatory infiltration. Hemoglobin (Hb), heme, and iron released after red blood cell lysis aggravate ICH-induced inflammatory injury. Danger associated molecular patterns such as high mobility group box 1 protein, released from damaged or dead cells, trigger inflammation in the late stage of ICH. Preclinical studies have identified inflammatory signaling pathways that are involved in microglial activation, leukocyte infiltration, toll-like receptor (TLR) activation, and danger associated molecular pattern regulation in ICH. Recent advances in understanding the pathogenesis of ICH-induced inflammatory injury have facilitated the identification of several novel therapeutic targets for the treatment of ICH. This review summarizes recent progress concerning the mechanisms underlying ICH-induced inflammation. We focus on the inflammatory signaling pathways involved in microglial activation and TLR signaling, and explore potential therapeutic interventions by targeting the removal of hematoma components and inhibition of TLR signaling.

Toll-like receptor 4 signaling in intracerebral hemorrhage-induced inflammation and injury

Intracerebral hemorrhage (ICH) is a common type of fatal stroke, accounting for about 15% to 20% of all strokes. Hemorrhagic strokes are associated with high mortality and morbidity, and increasing evidence shows that innate immune responses and inflammatory injury play a critical role in ICH-induced neurological deficits. However, the signaling pathways involved in ICH-induced inflammatory responses remain elusive. Toll-like receptor 4 (TLR4) belongs to a large family of pattern recognition receptors that play a key role in innate immunity and inflammatory responses. In this review, we summarize recent findings concerning the involvement of TLR4 signaling in ICH-induced inflammation and brain injury. We discuss the key mechanisms associated with TLR4 signaling in ICH and explore the potential for therapeutic intervention by targeting TLR4 signaling.