scholarly journals PSD-95: An Effective Target for Stroke Therapy Using Neuroprotective Peptides

2021 ◽  
Vol 22 (22) ◽  
pp. 12585
Author(s):  
Lola Ugalde-Triviño ◽  
Margarita Díaz-Guerra

Therapies for stroke have remained elusive in the past despite the great relevance of this pathology. However, recent results have provided strong evidence that postsynaptic density protein-95 (PSD-95) can be exploited as an efficient target for stroke neuroprotection by strategies able to counteract excitotoxicity, a major mechanism of neuronal death after ischemic stroke. This scaffold protein is key to the maintenance of a complex framework of protein interactions established at the postsynaptic density (PSD) of excitatory neurons, relevant to neuronal function and survival. Using cell penetrating peptides (CPPs) as therapeutic tools, two different approaches have been devised and advanced to different levels of clinical development. First, nerinetide (Phase 3) and AVLX-144 (Phase 1) were designed to interfere with the coupling of the ternary complex formed by PSD-95 with GluN2B subunits of the N-methyl-D-aspartate type of glutamate receptors (NMDARs) and neuronal nitric oxide synthase (nNOS). These peptides reduced neurotoxicity derived from NMDAR overactivation, decreased infarct volume and improved neurobehavioral results in different models of ischemic stroke. However, an important caveat to this approach was PSD-95 processing by calpain, a pathological mechanism specifically induced by excitotoxicity that results in a profound alteration of survival signaling. Thus, a third peptide (TP95414) has been recently developed to interfere with PSD-95 cleavage and reduce neuronal death, which also improves neurological outcome in a preclinical mouse model of permanent ischemia. Here, we review recent advancements in the development and characterization of PSD-95-targeted CPPs and propose the combination of these two approaches to improve treatment of stroke and other excitotoxicity-associated disorders.

2021 ◽  
Author(s):  
Pian Gong ◽  
Yichun Zou ◽  
Wei Zhang ◽  
Qi Tian ◽  
Shoumeng Han ◽  
...  

Abstract Insulin-like growth factor 1 (IGF-1) exhibits neuroprotective properties, such as vasodilatory and anti-inflammatory effects following ischemic stroke. However, the specific molecular mechanisms of action of IGF-1 following ischemic stroke remain elusive. We wanted to explore whether IGF-1 regulates Hippo/YAP signaling pathway, potentially via activation of the PI3K/AKT signaling pathway to exert its neuroprotective effects following ischemic stroke. In the in vitro study, we used oxygen–glucose deprivation to injure cultured PC12 and SH-5YSY cells, and cortical primary neurons. Cell viability was measured using CCK-8 assay. For the in vivo analyses, Sprague–Dawley rats were subjected to middle cerebral artery occlusion; neurological function was assessed using the neurological deficit score; infarct volume was measured using triphenyltetrazolium chloride staining, and neuronal death and apoptosis was evaluated by TUNEL staining, H&E staining and Nissl staining. Western blot was used to measure the levels of YAP/TAZ, PI3K and phosphorylated AKT (p-AKT) both in vitro and in vivo. We found that IGF-1 induced activation of YAP/TAZ, which resulted in improved cell viability in vitro, and decreased neurological deficits, neuronal death and apoptosis, and cerebral infarct volume in vivo. Notably, the neuroprotective effects of IGF-1 were reversed by an inhibitor of the PI3K/AKT signaling pathway, LY294002, which not only reduced expressions of PI3K and p-AKT, but also down-regulated expression of YAP/TAZ, leading to aggravation of neurological dysfunction. These findings indicate that neuroprotective effect of IGF-1 is partly realized by up-regulation of YAP/TAZ, which is mediated by activation of the PI3K/AKT signaling pathway following cerebral ischemic stroke.


Antioxidants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 291 ◽  
Author(s):  
Emma Martínez-Alonso ◽  
Alejandro Escobar-Peso ◽  
Maria I. Ayuso ◽  
Rafael Gonzalo-Gobernado ◽  
Mourad Chioua ◽  
...  

Nitrones have a well-recognized capacity as spin-traps and are considered powerful free radical scavengers, which are two important issues in hypoxia-induced oxidative stress and cell death in brain ischemia. Consequently, nitrones have been proposed as therapeutic agents in acute ischemic stroke (AIS). In this paper, we update the biological and pharmacological characterization of ISQ-201, a previously identified cholesteronitrone hybrid with antioxidant and neuroprotective activity. This study characterizes ISQ-201 as a neuroprotective agent against the hypoxia-induced ischemic injury. Transitory four-vessel occlusion and middle cerebral artery occlusion (tMCAO) were used to induce cerebral ischemia. Functional outcomes were determined using neurofunctional tests. Infarct area, neuronal death, and apoptosis induction were evaluated. In addition, ISQ-201 reactivity towards free radicals was studied in a theoretical model. ISQ-201 significantly decreased the ischemia-induced neuronal death and apoptosis, in a dose-dependent manner, showing its therapeutic effect when administered up until 6 h after post-ischemic reperfusion onset, effects that remained after 3 months from the ischemic episode. Furthermore, ISQ-201 significantly reduced infarct volume, leading to recovery of the motor function in the tMCAO model. Finally, the theoretical study confirmed the reactivity of ISQ-201 towards hydroxyl radicals. The results reported here prompted us to suggest ISQ-201 as a promising candidate for the treatment of AIS.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Joen-Rong Sheu ◽  
Zhih-Cherng Chen ◽  
Thanasekaran Jayakumar ◽  
Duen-Suey Chou ◽  
Ting-Lin Yen ◽  
...  

Abstract Thrombosis and stroke are major causes of disability and death worldwide. However, the regular antithrombotic drugs may have unsatisfactory results and side effects. Platonin, a cyanine photosensitizing dye, has been used to treat trauma, ulcers and some acute inflammation. Here, we explored the neuroprotective effects of platonin against middle cerebral artery occlusion (MCAO)-induced ischemic stroke in mice. Platonin(200 μg/kg) substantially reduced cerebral infarct volume, brain edema, neuronal cell death and neurological deficit scores, and improved the MCAO-reduced locomotor activity and rotarod performance. Platonin(5–10 μM) potently inhibited platelet aggregation and c-Jun NH2-terminal kinase (JNK) phosphorylation in collagen-activated platelets. The antiaggregation effect did not affect bleeding time but increased occlusion time in platonin(100 and 200 μg/kg)-treated mice. Platonin(2–10 μM) was potent in diminishing collagen- and Fenton reaction-induced ∙OH formation. Platonin(5–10 μM) also suppressed the expression of nitric oxide, inducible nitric oxide synthase, cyclooxygenase-2, interleukin-1β, and JNK phosphorylation in lipopolysaccharide-stimulated macrophages. MCAO-induced expression of 3-nitrotyrosine and Iba1 was apparently attenuated in platonin(200 μg/kg)-treated mice. In conclusion, platonin exhibited remarkable neuroprotective properties against MCAO-induced ischemia in a mouse model through its antiaggregation, antiinflammatory and antiradical properties. The observed therapeutic efficacy of platonin may consider being a novel medcine against ischemic stroke.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuejiao Li ◽  
Yankai Dong ◽  
Ye Ran ◽  
Yanan Zhang ◽  
Boyao Wu ◽  
...  

Abstract Background We show previously that three-dimensional (3D) spheroid cultured mesenchymal stem cells (MSCs) exhibit reduced cell size thus devoid of lung entrapment following intravenous (IV) infusion. In this study, we determined the therapeutic effect of 3D-cultured MSCs on ischemic stroke and investigated the mechanisms involved. Methods Rats underwent middle cerebral artery occlusion (MCAO) and reperfusion. 1 × 106 of 3D- or 2D-cultured MSCs, which were pre-labeled with GFP, were injected through the tail vain three and seven days after MCAO. Two days after infusion, MSC engraftment into the ischemic brain tissues was assessed by histological analysis for GFP-expressing cells, and infarct volume was determined by MRI. Microglia in the lesion were sorted and subjected to gene expressional analysis by RNA-seq. Results We found that infusion of 3D-cultured MSCs significantly reduced the infarct volume of the brain with increased engraftment of the cells into the ischemic tissue, compared to 2D-cultured MSCs. Accordingly, in the brain lesion of 3D MSC-treated animals, there were significantly reduced numbers of amoeboid microglia and decreased levels of proinflammatory cytokines, indicating attenuated activation of the microglia. RNA-seq of microglia derived from the lesions suggested that 3D-cultured MSCs decreased the response of microglia to the ischemic insult. Interestingly, we observed a decreased expression of mincle, a damage-associated molecular patterns (DAMPs) receptor, which induces the production of proinflammatory cytokines, suggestive of a potential mechanism in 3D MSC-mediated enhanced repair to ischemic stroke. Conclusions Our data indicate that 3D-cultured MSCs exhibit enhanced repair to ischemic stroke, probably through a suppression to ischemia-induced microglial activation.


2021 ◽  
pp. 0271678X2199298
Author(s):  
Chao Li ◽  
Chunyang Wang ◽  
Yi Zhang ◽  
Owais K Alsrouji ◽  
Alex B Chebl ◽  
...  

Treatment of patients with cerebral large vessel occlusion with thrombectomy and tissue plasminogen activator (tPA) leads to incomplete reperfusion. Using rat models of embolic and transient middle cerebral artery occlusion (eMCAO and tMCAO), we investigated the effect on stroke outcomes of small extracellular vesicles (sEVs) derived from rat cerebral endothelial cells (CEC-sEVs) in combination with tPA (CEC-sEVs/tPA) as a treatment of eMCAO and tMCAO in rat. The effect of sEVs derived from clots acquired from patients who had undergone mechanical thrombectomy on healthy human CEC permeability was also evaluated. CEC-sEVs/tPA administered 4 h after eMCAO reduced infarct volume by ∼36%, increased recanalization of the occluded MCA, enhanced cerebral blood flow (CBF), and reduced blood-brain barrier (BBB) leakage. Treatment with CEC-sEVs given upon reperfusion after 2 h tMCAO significantly reduced infarct volume by ∼43%, and neurological outcomes were improved in both CEC-sEVs treated models. CEC-sEVs/tPA reduced a network of microRNAs (miRs) and proteins that mediate thrombosis, coagulation, and inflammation. Patient-clot derived sEVs increased CEC permeability, which was reduced by CEC-sEVs. CEC-sEV mediated suppression of a network of pro-thrombotic, -coagulant, and -inflammatory miRs and proteins likely contribute to therapeutic effects. Thus, CEC-sEVs have a therapeutic effect on acute ischemic stroke by reducing neurovascular damage.


Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Hannah J Irvine ◽  
Thomas W Battey ◽  
Ann-Christin Ostwaldt ◽  
Bruce C Campbell ◽  
Stephen M Davis ◽  
...  

Introduction: Revascularization is a robust therapy for acute ischemic stroke, but animal studies suggest that reperfusion edema may attenuate its beneficial effects. In stroke patients, early reperfusion consistently reduces infarct volume and improves long-term functional outcome, but there is little clinical data available regarding reperfusion edema. We sought to elucidate the relationship between reperfusion and brain edema in a patient cohort of moderate to severe stroke. Methods: Seventy-one patients enrolled in the Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) with serial brain magnetic resonance imaging and perfusion-weighted imaging (PWI) were analyzed. Reperfusion percentage was calculated based on the difference in PWI lesion volume at baseline and follow-up (day 3-5). Midline shift (MLS) was measured on the day 3-5 fluid attenuated inversion recovery (FLAIR) sequence. Swelling volume and infarct growth volume were assessed using region-of-interest analysis on the baseline and follow-up DWI scans based on our prior methods. Results: Greater percentage of reperfusion was associated with less MLS (Spearman ρ = -0.46; P <0.0001) and reduced swelling volume (Spearman ρ = -0.56; P <0.0001). In multivariate analysis, reperfusion was an independent predictor of less MLS ( P <0.006) and decreased swelling volume ( P <0.0054), after adjusting for age, baseline NIHSS, admission blood glucose, baseline DWI volume, and IV tPA treatment. Conclusions: Reperfusion is associated with reduced brain edema as measured by MLS and swelling volume. While our data do not exclude the possibility of reperfusion edema in certain circumstances, in stroke patients, reperfusion following acute stroke is predominantly linked to less brain swelling.


Stroke ◽  
2021 ◽  
Author(s):  
Shadi Yaghi ◽  
Eytan Raz ◽  
Seena Dehkharghani ◽  
Howard Riina ◽  
Ryan McTaggart ◽  
...  

Background and Purpose: In patients with acute large vessel occlusion, the natural history of penumbral tissue based on perfusion time-to-maximum (T max ) delay is not well established in relation to late-window endovascular thrombectomy. In this study, we sought to evaluate penumbra consumption rates for T max delays in patients with large vessel occlusion evaluated between 6 and 16 hours from last known normal. Methods: This is a post hoc analysis of the DEFUSE 3 trial (The Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke), which included patients with an acute ischemic stroke due to anterior circulation occlusion within 6 to 16 hours of last known normal. The primary outcome is percentage penumbra consumption, defined as (24-hour magnetic resonance imaging infarct volume–baseline core infarct volume)/(T max 6 or 10 s volume–baseline core volume). We stratified the cohort into 4 categories based on treatment modality and Thrombolysis in Cerebral Infarction (TICI score; untreated, TICI 0-2a, TICI 2b, and TICI3) and calculated penumbral consumption rates in each category. Results: We included 141 patients, among whom 68 were untreated. In the untreated versus TICI 3 patients, a median (interquartile range) of 53.7% (21.2%–87.7%) versus 5.3% (1.1%–14.6%) of penumbral tissue was consumed based on T max >6 s ( P <0.001). In the same comparison for T max >10 s, we saw a difference of 165.4% (interquartile range, 56.1%–479.8%) versus 25.7% (interquartile range, 3.2%–72.1%; P <0.001). Significant differences were not demonstrated between untreated and TICI 0-2a patients for penumbral consumption based on T max >6 s ( P =0.52) or T max >10 s ( P =0.92). Conclusions: Among extended window endovascular thrombectomy patients, T max >10-s mismatch volume may comprise large volumes of salvageable tissue, whereas nearly half the T max >6-s mismatch volume may remain viable in untreated patients at 24 hours.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Johanna Ospel ◽  
Michael D Hill ◽  
Nima Kashani ◽  
Arnuv Mayank ◽  
Nishita Singh ◽  
...  

Purpose: We investigated the prevalence and prognostic impact on outcome of any intracranial hemorrhage, hemorrhage morphology, type and volume in acute ischemic stroke patients undergoing mechanical thrombectomy. Methods: Prevalence of intracranial hemorrhage, hemorrhage type, morphology and volume was determined on 24h follow-up imaging (non contrast head CT or gradient-echo/susceptibility-weighted MRI). Proportions of good outcome (mRS 0-2 at 90 days) were reported for patients with vs. without any intracranial hemorrhage. Multivariable logistic regression with adjustment for key minimization variables and total infarct volume was performed to obtain adjusted effect size estimates for hemorrhage type and volume on good outcome. Results: Hemorrhage on follow up-imaging was seen in 372/1097 (33.9%) patients, among them 126 (33.9%) with hemorrhagic infarction (HI) type 1, 108 (29.0%) with HI-2, 72 /19.4%) with parenchymal hematoma (PH) type 1, 37 (10.0) with PH2, 8 (2.2%) with remote PH and 21 (5.7%) with extra-parenchymal/intraventricular hemorrhage. Good outcomes were less often achieved by patients with hemorrhage on follow-up imaging (164/369 [44.4%] vs. 500/720 [69.4%]). Any type of intracranial hemorrhage was strongly associated with decreased chances of good outcome ( adj OR 0.62 [CI 95 0.44 - 0.87]). The effect of hemorrhage was driven by both PH hemorrhage sub-type [PH-1 ( adj OR 0.39 [CI 95 0.21 - 0.72]), PH-2 ( adj OR 0.15 [CI 95 0.05 - 0.50])] and extra-parenchymal/intraventricular hemorrhage ( adj OR 0.60 (0.20-1.78) Petechial hemorrhages (HI-1 and HI-2) were not associated with poorer outcomes. Hemorrhage volume ( adj OR 0.97 [CI 95 0.05 - 0.99] per ml increase) was significantly associated with decreased chances of good outcome. Conclusion: Presence of any hemorrhage on follow-up imaging was seen in one third of patients and strongly associated with decreased chances of good outcome.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Sydney Claypoole ◽  
Jacqueline Frank ◽  
Madison Sands ◽  
Christopher J McLouth ◽  
Jill Roberts ◽  
...  

Introduction: The previously published Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) protocol (clinicaltrials.gov NCT03153683) utilizes mechanical thrombectomy to obtain tissue samples for banking. Peripheral blood proximal to the clot and intracranial blood distal from the clot were isolated. Proteomic and statistical analyses revealed normalized (intracranial-systemic) CCL19 expression was a predictor of infarct volume. Statistical modeling analyses were used determine the CCL19-associated proteomic signaling network occurring during ischemic stroke relating to infarct volume. Methods: Arterial intracranial and systemic blood samples underwent analysis for inflammatory proteins using Proximity Extension Assay (PEA) via Olink (Olink Proteomics, Boston, MA). Systemic expression was used as an internal control to normalize expression in the intracranial blood. Bivariate regression was used to examine the relationship between the intracranial normalized CCL19 expression and infarct volume. A backwards stepwise regression was then used to determine a model of predictability of infarct volume by CCL19 and associated inflammatory proteins. Results: 25 subjects (>18 yrs) with a mean infarct volume of 8,172 ± 82,284 mm 3 and mean infarct time of 513 ± 246 minutes were included in this study. Their median age was 64 (24-91) and 10 (40%) were male. 16 subjects (64%) had hypertension, 15 (60%) had BMI > 25, and 6 (24%) had a previous stroke. The stepwise regression model shows normalized expression of 16 proteins correlated with an increase in infarct volume (p<0.005): CCL20, CXCL1, OSM, CD6, OSMR, TGF-alpha, TRANCE, CXCL10, LIF-R, CCL19, CDCP1, Flt3L, CCL23, CD244, TRAIL, NOTCH1. Conclusions: In our model, the expression of these proteins were consistently changed, though the directionality differed. LIF-R, NOTCH1, TRAIL, CD6, CCL23, TGF-alpha, and CCL20 were positively correlated, while the expressions of Flt3L, OSM, OSMR, TRANCE, CD244, CDCP1, CXCL1, CXCL10, and CCL19 were negatively correlated with infarct volume. This model depicts the proteomic signaling occurring during stroke in relationship to infarct volume, which reveals potential biomarkers and therapeutic targets for the early phase of ischemic stroke.


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