scholarly journals Identification and Characterization of NTB451 as a Potential Inhibitor of Necroptosis

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2884 ◽  
Author(s):  
Eun-Jung In ◽  
Yuno Lee ◽  
Sushruta Koppula ◽  
Tae-Yeon Kim ◽  
Jun-Hyuk Han ◽  
...  
Keyword(s):  
Cell Death ◽  
Md Simulation ◽  
Ischemia Reperfusion Injury ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Direct Interaction ◽  
Inhibitory Effect ◽  
Therapeutic Implications ◽  
Pathological Conditions ◽  
Tnf Α

Necroptosis, or caspase-independent programmed cell death, is known to be involved in various pathological conditions, such as ischemia/reperfusion injury, myocardial infarction, atherosclerosis, and inflammatory bowel diseases. Although several inhibitors of necroptosis have been identified, none of them are currently in clinical use. In the present study, we identified a new compound, 4-({[5-(4-aminophenyl)-4-ethyl-4H-1,2,4-triazol-3-yl]sulfanyl}methyl)-N-(1,3-thiazol-2-yl) benzamide (NTB451), with significant inhibitory activity on the necroptosis induced by various triggers, such as tumor necrosis factor-α (TNF-α) and toll-like receptor (TLR) agonists. Mechanistic studies revealed that NTB451 inhibited phosphorylation and oligomerization of mixed lineage kinase domain like (MLKL), and this activity was linked to its inhibitory effect on the formation of the receptor interacting serine/threonine-protein kinase 1 (RIPK1)-RIPK3 complex. Small interfering RNA (siRNA)-mediated RIPK1 knockdown, drug affinity responsive target stability assay, and molecular dynamics (MD) simulation study illustrated that RIPK1 is a specific target of NTB451. Moreover, MD simulation showed a direct interaction of NTB451 and RIPK1. Further experiments to ensure that the inhibitory effect of NTB451 was restricted to necroptosis and NTB451 had no effect on nuclear factor-κB (NF-κB) activation or apoptotic cell death upon triggering with TNF-α were also performed. Considering the data obtained, our study confirmed the potential of NTB451 as a new necroptosis inhibitor, suggesting its therapeutic implications for pathological conditions induced by necroptotic cell death.

Abstract TP266: Phenothiazines Enhance Mild Hypothermia-induced Neuroprotection via PI3K/Akt Regulation in Experimental Ischemia/Reperfusion Injury

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Hong An ◽  
Joshua Wright ◽  
Yunxia Duan ◽  
Di Wu ◽  
Xunming Ji ◽  
...  
Keyword(s):  
Cell Death ◽  
Ischemia Reperfusion Injury ◽  
Mild Hypothermia ◽  
Apoptotic Cell ◽  
Infarct Volume ◽  
Ischemia Reperfusion ◽  
Akt Signaling ◽  
Akt Signaling Pathway ◽  
Neuroprotective Effects ◽  
Apoptotic Proteins

Introduction: Hypothermia is an effective neuroprotectant against stroke, but its application is limited by delayed onset, prolonged duration, and significant complications. Mild hypothermia is more clinically practical but offers weaker neuroprotection. This study investigated whether the neuroprotective effects of mild hypothermia can be enhanced by phenothiazine neuroleptics (chlorpromazine and promethazine), which were reported to have depressive or hibernation-like roles on the CNS. We also worked to elucidate the role of the PI3K/Akt signaling pathway in this protective mechanism. Methods: A total of 131 adult male Sprague-Dawley rats were randomly divided into 6 groups: sham, stroke without treatment (2-hour right middle cerebral artery occlusion), and 4 treatment groups with 1) mild hypothermia (anal temperature 33-35 0 C), 2) phenothiazines (1mg/kg chlorpromazine & 1mg/kg promethazine, anal temperature 37.8-38.3 0 C), 3) combination of mild hypothermia and phenothiazines, and 4) both therapies with the addition of a p-Akt antagonist (LY294002 was injected into the lateral ventricle 30 minutes before ischemia). Infarct volume, neurological deficit, and apoptotic cell death were determined 24h post reperfusion. Expression of p-Akt, cleaved Caspase-3, pro-apoptotic (AIF & Bax) and anti-apoptotic proteins (Bcl-2 & Bcl-xL) was assessed by Western blot at 6h and 24h after reperfusion. Results: The combination of hypothermia and phenothiazines decreased (P<0.01) infarct volume and neurological deficit. This change was associated with a reduction (P<0.01) of apoptotic cell death. Each treatment alone did not induce significant neuroprotection. The combination therapy, but not each alone, promoted (P<0.01) the expression of p-Akt, accompanied with increased expression of anti-apoptotic proteins and decreased expression of pro-apoptotic proteins. The neuroprotective effects were blocked by p-Akt inhibition. Conclusion: Mild hypothermia-induced neuroprotection was enhanced by phenothiazines in an experimental ischemia/reperfusion injury model. This study supports the involvement of the PI3K/Akt signaling pathway. This novel therapeutic strategy could be developed as an effective treatment for acute ischemic stroke.

Detection of early stages of apoptosis in experimental intestinal ischemia-reperfusion injury

Biologia ◽  
2007 ◽  
Vol 62 (4) ◽  
Author(s):  
Štefan Tóth ◽  
Mikuláš Pomfy ◽  
Peter Wohlfahrt ◽  
Stanislava Pingorová ◽  
Ján Kišš ◽  
...  
Keyword(s):  
Cell Death ◽  
Small Intestine ◽  
Intestinal Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Apoptotic Index ◽  
Regeneration Ability ◽  
Total Proportion ◽  
Intestinal Ischemia Reperfusion

AbstractApoptosis is a form of programmed cell death that plays an important role in small intestine ischemia-reperfusion (IR) injury. The aim of this study was to determine the total proportion of apoptotic cell death (apoptotic index) following injury induced by ischemia and during various subsequent reperfusion periods, total histopathological status and the intestine regeneration dynamics after the IR injury. Experimental animals, Wistar rats (n = 45) were divided into three experimental and one control groups. In the experimental groups 1 h ischemia was followed by 1, 4 and 24 h reperfusion. Intestinal ischemia was induced by superior mesenteric artery (SMA) occlusion. Segments of jejunum were stained with hematoxylin and eosin and studied immunohistochemically using M30 CytoDEATH and in situ TUNEL methods for apoptosis detection. Our experimental data showed that: (i) apoptosis is an important form of cell death in the small intestine after IR injury induced by SMA occlusion; (ii) maximum levels of histopathological damage and apoptotic index of mucosa occurred after 1 h ischemia and 1 h of reperfusion; and (iii) mucosa possesses great regeneration ability. The lowest levels of histopathological damage and apoptotic index were observed in the group with 1 h ischemia and 24 h reperfusion where, however, the highest mitotic index was present.

scholarly journals Sex-related resistance to myocardial ischemia-reperfusion injury is associated with high constitutive ARC expression

2010 ◽  
Vol 298 (5) ◽  
pp. H1510-H1517 ◽  
Author(s):  
Wobbe Bouma ◽  
Mio Noma ◽  
Shinya Kanemoto ◽  
Muneaki Matsubara ◽  
Bradley G. Leshnower ◽  
...  
Keyword(s):  
Cell Death ◽  
Infarct Size ◽  
Ischemia Reperfusion Injury ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Apoptotic Cell Death ◽  
Cardiomyocyte Apoptosis ◽  
Myocardial Salvage ◽  
Area At Risk ◽  
Myocardial Area

The female sex has been associated with improved myocardial salvage after ischemia and reperfusion (I/R). Estrogen, specifically 17β-estradiol, has been demonstrated to mediate this phenomenon by limiting cardiomyocyte apoptosis. We sought to quantitatively assess the effect of sex, ovarian hormone loss, and I/R on myocardial Bax, Bcl-2, and apoptosis repressor with caspase recruitment domain (ARC) expression. Male ( n = 48), female ( n = 26), and oophorectomized female ( n = 20) rabbits underwent 30 min of regional ischemia and 3 h of reperfusion. The myocardial area at risk and infarct size were determined using a double-staining technique and planimetry. In situ oligo ligation was used to assess apoptotic cell death. Western blot analysis was used to determine proapoptotic (Bax) and antiapoptotic (Bcl-2 and ARC) protein levels in all three ischemic groups and, additionally, in three nonischemic groups. Infarct size (43.7 ± 3.2%) and apoptotic cell death (0.51 ± 0.10%) were significantly attenuated in females compared with males (56.4 ± 1.6%, P < 0.01, and 4.29 ± 0.95%, P < 0.01) and oophorectomized females (55.7 ± 3.4%, P < 0.05, and 4.36 ± 0.51%, P < 0.01). Females expressed significantly higher baseline ARC levels (3.62 ± 0.29) compared with males (1.78 ± 0.18, P < 0.01) and oophorectomized females (1.08 ± 0.26, P < 0.01). Males expressed a significantly higher baseline Bax-to-Bcl-2 ratio (4.32 ± 0.99) compared with females (0.65 ± 0.13, P < 0.01) and oophorectomized females (0.42 ± 0.10, P < 0.01). I/R significantly reduced Bax-to-Bcl-2 ratios in males. In all other groups, ARC levels and Bax-to-Bcl-2 ratios did not significantly change. These results support the conclusion that in females, endogenous estrogen limits I/R-induced cardiomyocyte apoptosis by producing a baseline antiapoptotic profile, which is associated with estrogen-dependent high constitutive myocardial ARC expression.

scholarly journals Proteomic mapping of proteins released during necrosis and apoptosis from cultured neonatal cardiac myocytes

2014 ◽  
Vol 306 (7) ◽  
pp. C639-C647 ◽  
Author(s):  
Kurt D. Marshall ◽  
Michelle A. Edwards ◽  
Maike Krenz ◽  
J. Wade Davis ◽  
Christopher P. Baines
Keyword(s):  
Cell Death ◽  
Cardiac Myocytes ◽  
Cardiac Myocyte ◽  
Ischemia Reperfusion Injury ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Cardiac Injury ◽  
High Mobility ◽  
Neonatal Rat ◽  
Protein Markers

Cardiac injury induces myocyte apoptosis and necrosis, resulting in the secretion and/or release of intracellular proteins. Currently, myocardial injury can be detected by analysis of a limited number of biomarkers in blood or coronary artery perfusate. However, the complete proteomic signature of protein release from necrotic cardiac myocytes is unknown. Therefore, we undertook a proteomic-based study of proteins released from cultured neonatal rat cardiac myocytes in response to H2O2 (necrosis) or staurosporine (apoptosis) to identify novel specific markers of cardiac myocyte cell death. Necrosis and apoptosis resulted in the identification of 147 and 79 proteins, respectively. Necrosis resulted in a relative increase in the amount of many proteins including the classical necrotic markers lactate dehydrogenase (LDH), high-mobility group B1 (HMGB1), myoglobin, enolase, and 14-3-3 proteins. Additionally, we identified several novel markers of necrosis including HSP90, α-actinin, and Trim72, many of which were elevated over control levels earlier than classical markers of necrotic injury. In contrast, the majority of identified proteins remained at low levels during apoptotic cell death, resulting in no candidate markers for apoptosis being identified. Blotting for a selection of these proteins confirmed their release during necrosis but not apoptosis. We were able to confirm the presence of classical necrotic markers in the extracellular milieu of necrotic myocytes. We also were able to identify novel markers of necrotic cell death with relatively early release profiles compared with classical protein markers of necrosis. These results have implications for the discovery of novel biomarkers of necrotic myocyte injury, especially in the context of ischemia-reperfusion injury.

Verapamil Reduces Coronary Endothelium Damage and Cardiomyocyte Necrosis but not Apoptosis after Ischemia and Reperfusion: Ex Vivo Study in Rat Hearts

2002 ◽  
Vol 15 (3) ◽  
pp. 225-232 ◽  
Author(s):  
P. Di Napoli ◽  
A. A. Taccardi ◽  
A. Grilli ◽  
M. Felaco ◽  
L. Di Gioacchino ◽  
...  
Keyword(s):  
Cell Death ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Cardiomyocyte Apoptosis ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Heart Weight ◽  
Acute Administration ◽  
Rat Hearts

We tested the hypothesis of beneficial effects of the calcium-blocker verapamil in a model of ischemia-reperfusion, and investigated its effects against coronary microcirculation and cardiomyocyte apoptosis. Isolated working rat hearts were subjected to 15 min global ischemia and 22–180 min reperfusion in the presence or absence of verapamil (0.25 μM). We evaluated creatinephosphokinase (CK) in coronary effluent, heart weight changes, microvascular permeability (extravasation of fluoresceinelabeled albumin), ultrastructural alterations, and cardiomyocyte apoptosis (by 1.5% agarose gel electrophoresis and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling technique). In this model, 0.25 μM verapamil significantly reduced myocardial damage, CK release and vascular hyperpermeability, concomitant with a reduction in endothelial and cardiomyocyte lesions; on the contrary, 0.25 μM verapamil was unable to reduce cardiomyocyte apoptosis. In conclusion, in the absence of perfusing granulocytes, the acute administration of a pharmacologically relevant verapamil concentration reduces ischemia-reperfusion injury and prevents coronary endothelial cell and cardiomyocyte necrotic cell death but it is unable to reduce apoptotic cell death in isolated working rat hearts.

Prostacyclin-induced peroxisome proliferator-activated receptor-α translocation attenuates NF-κB and TNF-α activation after renal ischemia-reperfusion injury

2009 ◽  
Vol 297 (4) ◽  
pp. F1109-F1118 ◽  
Author(s):  
Hsi-Hsien Chen ◽  
Tzen-Wen Chen ◽  
Heng Lin
Keyword(s):  
Caspase 3 ◽  
Ischemia Reperfusion Injury ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Cell Number ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nitrogen Levels ◽  
Tnf Α

Prostacyclin and peroxisome proliferator-activated receptors (PPAR) protect against ischemia-reperfusion (I/R) injury by the induction of an anti-inflammatory pathway. In this study, we examined the prostacyclin-enhanced protective effect of PPARα in I/R-induced kidney injury. PPAR-α reduced the NF-κB-induced overexpression of TNF-α and apoptosis in cultured kidney cells. In a murine model, pretreating wild-type (WT) mice with a PPAR-α activator, docosahexaenoic acid (DHA), significantly reduced I/R-induced renal dysfunction (lowered serum creatinine and urea nitrogen levels), apoptotic responses (decreased apoptotic cell number and caspase-3, -8 activation), and NF-κB activation. By comparison, I/R-induced injury was exacerbated in PPAR-α knockout mice. This indicated that PPAR-α attenuated renal I/R injury via NF-κB-induced TNF-α overexpression. Overexpression of prostacyclin using an adenovirus could also induce PPAR-α translocation from the cytosol into the nucleus to inhibit caspase-3 activation. This prostacyclin/PPAR-α pathway attenuated TNF-α promoter activity by binding to NF-κB. Using a cAMP inhibitor (CAY10441) and a prostacyclin receptor antibody, we also found that there was another prostacyclin/IP receptor/cAMP pathway that could inhibit TNF-α production. Taken together, our results demonstrate for the first time that prostacyclin induces the translocation of PPAR-α from the cytosol into the nucleus and attenuates NF-κB-induced TNF-α activation following renal I/R injury. Treatments that can augment prostacyclin, PPAR-α, or the associated signaling pathways may ameliorate conditions associated with renal I/R injury.

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