Abstract WP324: Blocking Pro-Inflammatory Platelet-Activating Factor-Receptors and Activating Cell-Survival Pathways Leads to Neuroprotection After Experimental Ischemic Stroke

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Madigan M Reid ◽  
Eric J Knott ◽  
Ludmila Belayev ◽  
Larissa Khoutorova ◽  
Nicolas G Bazan
Keyword(s):  
Ischemic Stroke ◽  
Cell Survival ◽  
Molecular Mechanisms ◽  
Neuroprotective Effect ◽  
Platelet Activating Factor ◽  
Thromboxane B2 ◽  
Negative Ion ◽  
Neuroprotective Activity ◽  
Inflammatory Signaling ◽  
Survival Pathways

Objective: Acute ischemic stroke triggers complex neurovascular, neuroinflammatory, and synaptic alterations. Our study tested the prediction that blocking platelet-activating factor-receptors (PAF-Rs)-induced pro-inflammatory signaling plus administering a docosahexaenoic acid (DHA) after middle cerebral artery occlusion (MCAo) would lead to sustained neurological recovery. We used two molecules: a) LAU-0901, an antagonist of the PAF-R that blocks pro-inflammatory signaling and that has shown promising efficacy in a stroke model; and b) DHA, which activates cell-survival pathways and possesses potent anti-inflammatory and neuroprotective activity in the brain. Methods: Sprague-Dawley rats received 2h MCAo. Behavior was evaluated at 3, 4 and 24h. Treatments: LAU-0901 (i.p. 30mg/kg, 2h after onset of stroke), DHA (i.v. 5mg/kg, 3h after onset of stroke), LAU-0901+DHA and vehicle. On day 1, following lipids were extracted: Prostaglandins (PGE2, PGF2-α, 6-keto-PGF1a), Hydroxyoctadecadienoic acid (HODE), 11-dehydro-thromboxane B2, Thromboxane B2 (TXB2), 12-hydroxyeicosatetraenoic acid (12-HETE). Lipidomic analysis was conducted using LC-ESI-MS/MS in negative ion mode and results were normalized to total sample protein. Results: LAU-0901 and DHA treatments alone improved behavioral scores compared to vehicle groups by 30-35%. The neuroprotective effect was enhanced using the LAU-0901+DHA, which resulted in improved behavioral scores up to 47% on day 1. Expression of 12-HETE (proinflammatory marker) was reduced by DHA, LAU, LAU+DHA (83, 67, 72%, respectively). Conclusion: It is remarkable that there is differential expression of eicosanoid pathways and of other lipid mediators, some of them are proinflammatory, and other are modulators of neuroinflammation in the ipsilateral stroke side. We are currently exploring the detailed molecular mechanisms involved in the combination treatment of the PAF-R antagonist, LAU-0901, plus DHA.

scholarly journals Systems Pharmacology-Dissection of the Molecular Mechanisms of Dragon’s Blood in Improving Ischemic Stroke Prognosis

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Meng Jiang ◽  
Xing Su ◽  
Jianling Liu ◽  
Chunli Zheng ◽  
Xiaogang Li
Keyword(s):  
Ischemic Stroke ◽  
Cell Survival ◽  
Pc12 Cells ◽  
Molecular Mechanisms ◽  
Active Compounds ◽  
Dragon’S Blood ◽  
Anti Inflammatory ◽  
Main Component ◽  
Loureirin B ◽  
Anti Inflammation

Ethnopharmacological Relevance. Dragon’s blood (DB) is a widely used traditional Chinese medicine that has many pharmacological effects, including antiplatelet aggregation, promoting epidermal growth, and anti-inflammatory and antioxidant activities. The main component of Longxuetongluo capsule and Dragon’s blood dropping pills is DB’s standard phenolic extract, which was used for ischemic stroke prognosis in China. Aim of Study. To dissect the molecular mechanisms of Dragon’s blood (DB) in improving ischemic stroke prognosis. Materials and Methods. (1) Based on system-pharmacology platform, the potential active compounds of DB are screened out according to ADME. (2) The ischemic stroke-related targets are predicted by utilizing these active compounds as probes, mapping the targets to the CTD database to establish a molecular-target-disease network. (3) To analyze the mechanism of DB treatment for the prognosis of ischemic stroke, we used the Metascape and DAVID databases to construct “ischemic stroke pathways”. (4) PC12 cells were used to explore the protective effect of loureirin B on oxygen-glucose deprivation/reperfusion (OGD/R) injury, and BV-2 cells were used to determine the anti-inflammation effect of 4′,7-dihydroxyflavone. Results. Finally, we obtained 38 active compounds and 58 stroke-related targets. Network and pathway analysis indicate that DB is effective in the treatment of ischemic stroke by enhancing cell survival and inhibiting inflammatory and antiplatelet activation. In in vitro experiments, the main component loureirin B promoted the expression of HO-1 and Bcl-2 via positive regulation of PI3K/AKT/CREB and Nrf2 signaling pathways in PC12 cells against OGD/R damage. And the anti-inflammatory activity of 4′,7-dihydroxyflavone was related to the inhibition of COX-2, TNF-α, and IL-6 in LPS-induced BV-2 cells. Conclusions. In our study, the results illustrated that DB in improving ischemic stroke prognosis may involve enhancing cell survival and antioxidant, anti-inflammation, and antiplatelet activities.

scholarly journals Benzoinum exerts NVU protective effect by inhibiting cell apoptosis in cerebral ischemia rats

2020 ◽  
Author(s):  
Qian Xie ◽  
Rong Ma ◽  
Xiaoqing Guo ◽  
Hai Chen ◽  
Jian Wang
Keyword(s):  
Ischemic Stroke ◽  
Protective Effect ◽  
Cell Apoptosis ◽  
Caspase 3 ◽  
Neuroprotective Effect ◽  
Cerebrovascular Diseases ◽  
Neuroprotective Activity ◽  
Stroke Therapy ◽  
Function Score ◽  
Cerebral Ischemic

Abstract Background Benzoinum (Styraceae) is a traditional Chinese medicine known to treat stroke and other cardio-cerebrovascular diseases for thousands of years. Benzoinum also proved to have diverse pharmacological activity, but the neuroprotection mechanism about apoptosis in ischemic stroke were not found. This study is to investigate the NVU protective effect and mechanisms of benzoinum on cerebral ischemic rats. Methods The neuroprotective activity of benzoinum against MCAO induced cerebral ischemic injury. Neurological scores, TTC staining, HE staining were conducted to evaluate neurological damage. Infarction rate and DCI were calculated. The ultrastructure of neuron and BBB was observed by TEM. Immunohistochemistry and RT-PCR were used to detect the Bax, Bcl-2, Caspase 3 expression. In addition, Claudin 5 also was detected by immunohistochemistry. Results The findings shown that benzoinum could significantly improve the neurological function score, reduce the cerebral infarction rate and DCI. Furthermore, benzoinum alleviated pathomorphological change and apoptosis in brain tissue of MCAO rats. The results of TEM and claudin 5 expression of immunohistochemistry showed that benzoinum could play a neuroprotective effect in NVU. Besides, benzoinum enhanced Bcl2, reduced Bax and Bax/Bcl-2, Caspase 3, suggesting benzoinum provided neuroprotective effect by inhibited cell apoptosis. Conclusion Benzoinum could play a neuroprotective role and regulate apoptosis to repair and stabilize NVU. Our present findings provide a promising medicine for treatment of ischemic stroke therapy.

Cell-signalling in sperm midpiece ensures quiescence and survival in cauda epididymis

Reproduction ◽  
2021 ◽  
Author(s):  
Archana Devi ◽  
Bhavana Kushwaha ◽  
Jagdamba P Maikhuri ◽  
Rajender Singh ◽  
Gopal Gupta
Keyword(s):  
Cell Survival ◽  
Sperm Motility ◽  
Molecular Mechanisms ◽  
Mammalian Species ◽  
Cell Signalling ◽  
Sperm Concentration ◽  
Intracellular Signalling ◽  
Downstream Target ◽  
Survival Pathways ◽  
Sperm Midpiece

Sperm in most mammalian species including rat, mice and human are kept completely quiescent (motionless) and viable for up to a few weeks in the cauda epididymis before ejaculation. Vigorous motility is initiated almost instantly upon sperm release from cauda during ejaculation. The molecular mechanisms that suppress sperm motility but increase cell-survival during storage in cauda epididymis are not known. Intracellular signalling via phosphorylation cascades are quick events that may regulate motility and survival of transcriptionally inactive sperm. Pathscan® intracellular signalling array provided the preliminary picture of cell-signaling in quiescent and motile rat sperm, indicating upregulation of cell-survival pathways in quiescent sperm, which were downregulated during motility activation. Interactome of signalling-proteins involved in motility activation was constructed by STRING-software, which identified MAPK-p38, AKT, mTOR and their downstream target p70S6K as the key kinases regulating sperm function. Further validation was achieved by western-blotting and pathway activators/inhibitors. Immunofluorescence localized the kinase proteins in the sperm mid-piece region (mitochondria), a known extra-nuclear target for these signalling pathways. Activators of these kinases inhibited sperm motility but increased viability, and vice-versa was true for inhibitors, in most of the cases. Activators and inhibitors also affected sperm mitochondrial membrane potential, ATP content and ROS levels. Data suggest that sperm motility and survival are inversely complementary and critically regulated by intracellular cell signalling. Aberrant cell signalling in caudal sperm may affect cell survival (sperm concentration) and motility of ejaculated sperm.

scholarly journals Tocotrienols Modulate a Life or Death Decision in Cancers

2019 ◽  
Vol 20 (2) ◽  
pp. 372 ◽  
Author(s):  
Shiau-Ying Tham ◽  
Hwei-San Loh ◽  
Chun-Wai Mai ◽  
Ju-Yen Fu
Keyword(s):  
Cell Death ◽  
Cell Survival ◽  
Anticancer Agents ◽  
Molecular Mechanisms ◽  
Treatment Strategies ◽  
Promising Alternative ◽  
Cancer Cell Death ◽  
Survival Pathways ◽  
Cell Death Mechanisms ◽  
A Minor

Malignancy often arises from sophisticated defects in the intricate molecular mechanisms of cells, rendering a complicated molecular ground to effectively target cancers. Resistance toward cell death and enhancement of cell survival are the common adaptations in cancer due to its infinite proliferative capacity. Existing cancer treatment strategies that target a single molecular pathway or cancer hallmark fail to fully resolve the problem. Hence, multitargeted anticancer agents that can concurrently target cell death and survival pathways are seen as a promising alternative to treat cancer. Tocotrienols, a minor constituent of the vitamin E family that have previously been reported to induce various cell death mechanisms and target several key survival pathways, could be an effective anticancer agent. This review puts forward the potential application of tocotrienols as an anticancer treatment from a perspective of influencing the life or death decision of cancer cells. The cell death mechanisms elicited by tocotrienols, particularly apoptosis and autophagy, are highlighted. The influences of several cell survival signaling pathways in shaping cancer cell death, particularly NF-κB, PI3K/Akt, MAPK, and Wnt, are also reviewed. This review may stimulate further mechanistic researches and foster clinical applications of tocotrienols via rational drug designs.

Trimucytin: A Collagen-Like Aggregating Inducer Isolated from Trimeresurus mucrosquamatus Snake Venom

1993 ◽  
Vol 69 (03) ◽  
pp. 286-292 ◽  
Author(s):  
Che-Ming Teng ◽  
Feng-Nien Ko ◽  
Inn-Ho Tsai ◽  
Man-Ling Hung ◽  
Tur-Fu Huang
Keyword(s):  
Platelet Aggregation ◽  
Snake Venom ◽  
Inositol Phosphate ◽  
Shape Change ◽  
Platelet Activating Factor ◽  
Atp Release ◽  
Platelet Membrane ◽  
Thromboxane B2 ◽  
Dependent Manner ◽  
Concentration Dependent Manner

SummaryTrimucytin is a potent platelet aggregation inducer isolated from Trimeresurus mucrosquamatus snake venom. Similar to collagen, trimucytin has a run of (Gly-Pro-X) repeats at the N-terminal amino acids sequence. It induced platelet aggregation, ATP release and thromboxane formation in rabbit platelets in a concentration-dependent manner. The aggregation was not due to released ADP since it was not suppressed by creatine phosphate/creatine phosphokinase. It was not either due to thromboxane A2 formation because indomethacin and BW755C did not have any effect on the aggregation even thromboxane B2 formation was completely abolished by indomethacin. Platelet-activating factor (PAF) was not involved in the aggregation since a PAF antagonist, kadsurenone, did not affect. However, RGD-containing peptide triflavin inhibited the aggregation, but not the release of ATP, of platelets induced by trimucytin. Indomethacin, mepacrine, prostaglandin E1 and tetracaine inhibited the thromboxane B2 formation of platelets caused by collagen and trimucytin. Forskolin and sodium nitroprusside inhibited both platelet aggregation and ATP release, but not the shape change induced by trimucytin. In quin-2 loaded platelets, the rise of intracellular calcium concentration caused by trimucytin was decreased by 12-O-tetradecanoyl phorbol-13 acetate, imipramine, TMB-8 and indomethacin. In the absence of extracellular calcium, both collagen and trimucytin caused no thromboxane B2 formation, but still induced ATP release which was completely blocked by R 59022. Inositol phosphate formation in platelets was markedly enhanced by trimucytin and collagen. MAB1988, an antibody against platelet membrane glycoprotein Ia, inhibited trimucytinand collagen-induced platelet aggregation and ATP release. However, trimucytin did not replace the binding of 125I-labeled MAB1988 to platelets. Platelets pre-exposed to trimucytin were resistant to the second challenge with trimucytin itself or collagen. It is concluded that trimucytin may activate collagen receptors on platelet membrane, and cause aggregation and release mainly through phospholipase C-phosphoinositide pathway.

Tea bioactive components prevent carcinogenesis via anti‐pathogen, anti‐inflammation and cell survival pathways

IUBMB Life ◽  
2020 ◽  
Author(s):  
Xiangqi Fan ◽  
Xiangjun Xiao ◽  
Xiangbing Mao ◽  
Daiwen Chen ◽  
Bing Yu ◽  
...  
Keyword(s):  
Cell Survival ◽  
Bioactive Components ◽  
Survival Pathways ◽  
Anti Inflammation

scholarly journals Histatin-1 Attenuates LPS-Induced Inflammatory Signaling in RAW264.7 Macrophages

2021 ◽  
Vol 22 (15) ◽  
pp. 7856
Author(s):  
Sang Min Lee ◽  
Kyung-No Son ◽  
Dhara Shah ◽  
Marwan Ali ◽  
Arun Balasubramaniam ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Cytokine Production ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Mapk Signaling ◽  
Response To Treatment ◽  
No Production ◽  
Inflammatory Signaling ◽  
Raw264.7 Macrophages ◽  
Inflammatory Mediator Production

Macrophages play a critical role in the inflammatory response to environmental triggers, such as lipopolysaccharide (LPS). Inflammatory signaling through macrophages and the innate immune system are increasingly recognized as important contributors to multiple acute and chronic disease processes. Nitric oxide (NO) is a free radical that plays an important role in immune and inflammatory responses as an important intercellular messenger. In addition, NO has an important role in inflammatory responses in mucosal environments such as the ocular surface. Histatin peptides are well-established antimicrobial and wound healing agents. These peptides are important in multiple biological systems, playing roles in responses to the environment and immunomodulation. Given the importance of macrophages in responses to environmental triggers and pathogens, we investigated the effect of histatin-1 (Hst1) on LPS-induced inflammatory responses and the underlying molecular mechanisms in RAW264.7 (RAW) macrophages. LPS-induced inflammatory signaling, NO production and cytokine production in macrophages were tested in response to treatment with Hst1. Hst1 application significantly reduced LPS-induced NO production, inflammatory cytokine production, and inflammatory signaling through the JNK and NF-kB pathways in RAW cells. These results demonstrate that Hst1 can inhibit LPS-induced inflammatory mediator production and MAPK signaling pathways in macrophages.

scholarly journals LONP1 and ClpP cooperatively regulate mitochondrial proteostasis for cancer cell survival

Oncogenesis ◽  
2021 ◽  
Vol 10 (2) ◽  
Author(s):  
Yu Geon Lee ◽  
Hui Won Kim ◽  
Yeji Nam ◽  
Kyeong Jin Shin ◽  
Yu Jin Lee ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Growth ◽  
Cell Survival ◽  
Cancer Cell ◽  
Stress Responses ◽  
Molecular Mechanisms ◽  
Tca Cycle ◽  
Mitochondrial Matrix ◽  
Mitochondrial Functions ◽  
Cancer Cell Survival

AbstractMitochondrial proteases are key components in mitochondrial stress responses that maintain proteostasis and mitochondrial integrity in harsh environmental conditions, which leads to the acquisition of aggressive phenotypes, including chemoresistance and metastasis. However, the molecular mechanisms and exact role of mitochondrial proteases in cancer remain largely unexplored. Here, we identified functional crosstalk between LONP1 and ClpP, which are two mitochondrial matrix proteases that cooperate to attenuate proteotoxic stress and protect mitochondrial functions for cancer cell survival. LONP1 and ClpP genes closely localized on chromosome 19 and were co-expressed at high levels in most human cancers. Depletion of both genes synergistically attenuated cancer cell growth and induced cell death due to impaired mitochondrial functions and increased oxidative stress. Using mitochondrial matrix proteomic analysis with an engineered peroxidase (APEX)-mediated proximity biotinylation method, we identified the specific target substrates of these proteases, which were crucial components of mitochondrial functions, including oxidative phosphorylation, the TCA cycle, and amino acid and lipid metabolism. Furthermore, we found that LONP1 and ClpP shared many substrates, including serine hydroxymethyltransferase 2 (SHMT2). Inhibition of both LONP1 and ClpP additively increased the amount of unfolded SHMT2 protein and enhanced sensitivity to SHMT2 inhibitor, resulting in significantly reduced cell growth and increased cell death under metabolic stress. Additionally, prostate cancer patients with higher LONP1 and ClpP expression exhibited poorer survival. These results suggest that interventions targeting the mitochondrial proteostasis network via LONP1 and ClpP could be potential therapeutic strategies for cancer.

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