Potential role of TrkB agonist in neuronal survival by promoting CREB/BDNF and PI3K/Akt signaling in vitro and in vivo model of 3-nitropropionic acid (3-NP)-induced neuronal death

APOPTOSIS ◽  
2020 ◽  
Author(s):  
Sahabuddin Ahmed ◽  
Mohit Kwatra ◽  
Basveshwar Gawali ◽  
Samir Ranjan Panda ◽  
V. G. M. Naidu

2020 ◽  
Vol 19 ◽  
pp. 153303382097753
Author(s):  
Jingtao Wang ◽  
Jimin Zhang ◽  
Dongzhou Ma ◽  
Xiushan Li

To explore the role and mechanism of CERS1 in hypophysoma and investigate whether CERS1 overexpression can change the autophagy process of hypophysoma, and then to explore whether CERS1’s effect was regulated by the PI3K/AKT signaling pathway. Western blot and RT-PCR were used to analyze the expression or mRNA level of CERS1 at different tissues or cell lines. Afterwards, the occurrence and development of hypophysoma in vivo and in vitro, respectively, was observed by using CERS1 overexpression by lentivirus. Finally, MK-2206 and LY294002 were applied to discuss whether the role of CERS1 was regulated by the PI3K/AKT signaling pathway. Results show that the CERS1 expression and mRNA level in tumor or AtT-20 cells were decreased. CERS1 over-expressed by lentivirus could inhibit hypophysoma development in vivo and in vitro by reducing tumor volume and weight, weakening tumor proliferation and invasion, and enhancing apoptosis. In addition, shCERS1 could reverse the process. The above results indicate that CERS1 is possibly able to enhance autophagy in hypophysoma through the PI3K/AKT signaling pathway.



2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Judit Gil-Zamorano ◽  
João Tomé-Carneiro ◽  
María-Carmen Lopez de las Hazas ◽  
Lorena del Pozo-Acebo ◽  
M. Carmen Crespo ◽  
...  

Abstract The role of miRNAs in intestinal lipid metabolism is poorly described. The small intestine is constantly exposed to high amounts of dietary lipids, and it is under conditions of stress that the functions of miRNAs become especially pronounced. Approaches consisting in either a chronic exposure to cholesterol and triglyceride rich diets (for several days or weeks) or an acute lipid challenge were employed in the search for intestinal miRNAs with a potential role in lipid metabolism regulation. According to our results, changes in miRNA expression in response to fat ingestion are dependent on factors such as time upon exposure, gender and small intestine section. Classic and recent intestinal in vitro models (i.e. differentiated Caco-2 cells and murine organoids) partially mirror miRNA modulation in response to lipid challenges in vivo. Moreover, intestinal miRNAs might play a role in triglyceride absorption and produce changes in lipid accumulation in intestinal tissues as seen in a generated intestinal Dicer1-deletion murine model. Overall, despite some variability between the different experimental cohorts and in vitro models, results show that some miRNAs analysed here are modulated in response to dietary lipids, hence likely to participate in the regulation of lipid metabolism, and call for further research.



Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3916-3916
Author(s):  
Olga Dashevsky ◽  
Alexander Brill ◽  
Julia Rivo ◽  
David Varon

Abstract Platelet attachment to the subcellular matrix at injured sites of the vasculature is followed by their activation and release of microparticles. Platelet-derived microparticles (PMP) have been shown to be involved in the regulation of hemostasis. However, little is known about the role of PMP in the regulation of angiogenesis and related clinical conditions. We have recently demonstrated that platelets as a cellular system induce angiogenic responses both in vitro and in vivo. In the present study, we investigated the potential role of PMP in angiogenesis. A strong dose-dependent pro-angiogenic effect of PMP in the rat aortic ring model (5.3±2.1 mm2 surface covered with sprouting vessels versus 0.24±0.2 mm2 in the control, p<0.001) was observed. This effect was reversed by selective inhibition of VEGF, bFGF and PDGF (surface covered with vessels 0.7±0.5 mm2, 1.7±1.5 mm2, and 2.4±1.2 mm2, respectively, p<0.02 versus control), but not by inhibition of heparanase (5.1±0.8 mm2, p>0.5 versus control). PMP exert their stimulatory effect via PI3-kinase, Src kinase and ERK, whereas protein kinase C seems not to be involved, as judged by the aortic ring sprouting model. Using confocal and electron microscopy, we also demonstrate that PMP bind to non-activated endothelial cells. In addition, PMP markedly increased invasion of human endothelial cells through a layer of matrigel. This effect was abolished by an inhibitor of VEGF receptor tyrosine phosphorylation or laminaran sulfate (heparanase inhibitor). It was also partially reduced by PDGF blocking mAb, whereas blocking of bFGF had no effect. Furthermore, we have demonstrated that PMP induce angiogenesis in an in vivo model, in which beads (30 μl) of 4% agarose gel containing the substances under study were transplanted subcutaneously into mice. Image analysis of the capillary area revealed the following: control beads − 0.2±0.05 mm2, VEGF + bFGF containing beads − 4.8±1.1 mm2, PMP (100 μg/ml) containing beads − 5.1±1.3 mm2, p<0.001 versus control. The latter finding was further supported by immunohistochemical staining of the skin in the vicinity of the beads for von Willebrand factor, a marker of endothelial cells (control − 4.0±3.2, VEGF+bFGF − 12±4.4, PMP − 17±6.5 capillaries per view field, p<0.05 versus control). Finally, we explored the potential effect of PMP in a rat myocardial infarction model. Ischemia was induced by LAD ligation followed by injection of either PMP or PBS into the ischemic region. Preliminary evaluation of the LAD myocardial territory in sham-operated animals revealed 157±42.0 capillaries per view field. In contrast, number of capillaries observed 3 weeks after induction of ischemia was reduced to 34±21.5. When PMP were injected into the ischemic region, there was an increase in capillary number up to 97±27.3. In conclusion, PMP induce angiogenesis in both in vitro and in vivo models. Local injection of PMP into the ischemic myocardium may improve revascularization.



Blood ◽  
2010 ◽  
Vol 115 (20) ◽  
pp. 4083-4092 ◽  
Author(s):  
Frédéric Adam ◽  
Alexandre Kauskot ◽  
Paquita Nurden ◽  
Eric Sulpice ◽  
Marc F. Hoylaerts ◽  
...  

Abstract The role of c-Jun NH2-terminal kinase 1 (JNK1) in hemostasis and thrombosis remains unclear. We show here, with JNK1-deficient (JNK1−/−) mice, that JNK1 plays an important role in platelet biology and thrombus formation. In tail-bleeding assays, JNK1−/− mice exhibited longer bleeding times than wild-type mice (396 ± 39 seconds vs 245 ± 32 seconds). We also carried out in vitro whole-blood perfusion assays on a collagen matrix under arterial shear conditions. Thrombus formation was significantly reduced for JNK1−/− platelets (51%). In an in vivo model of thrombosis induced by photochemical injury to cecum vessels, occlusion times were 4.3 times longer in JNK1−/− arterioles than in wild-type arterioles. Moreover, in vitro studies carried out in platelet aggregation conditions demonstrated that, at low doses of agonists, platelet secretion was impaired in JNK1−/− platelets, leading to altered integrin αIIbβ3 activation and reduced platelet aggregation, via a mechanism involving protein kinase C. JNK1 thus appears to be essential for platelet secretion in vitro, consistent with its role in thrombus growth in vivo. Finally, we showed that ERK2 and another isoform of JNK affect platelet aggregation through 2 pathways, one dependent and another independent of JNK1.



2001 ◽  
Vol 132 (3) ◽  
pp. 693-702 ◽  
Author(s):  
David Pubill ◽  
Ester Verdaguer ◽  
Anna Ma Canudas ◽  
Francesc Xavier Sureda ◽  
Elena Escubedo ◽  
...  




2001 ◽  
Vol 33 (2) ◽  
pp. 95-102 ◽  
Author(s):  
Hyun-Young Park ◽  
Hyuck Moon Kwon ◽  
Hyun Joung Lim ◽  
Bum Kee Hong ◽  
Ju Yong Lee ◽  
...  


2010 ◽  
Vol 10 (9) ◽  
pp. S74-S75
Author(s):  
Mary Beth M. Grabowsky ◽  
Nicholas A. Pallotta ◽  
Matthew W. Connelly ◽  
Brett Van Etten ◽  
Rebecca A. MacDonald ◽  
...  


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.



2020 ◽  
Vol 55 ◽  
pp. 101466 ◽  
Author(s):  
Vanesa Sánchez-Giraldo ◽  
Yuliana Monsalve ◽  
Juliana Palacio ◽  
Miguel Mendivil-Perez ◽  
Ligia Sierra ◽  
...  


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