scholarly journals NT-4 attenuates neuroinflammation via TrkB/PI3K/FoxO1 pathway after germinal matrix hemorrhage in neonatal rats

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Tianyi Wang ◽  
Junyi Zhang ◽  
Peng Li ◽  
Yan Ding ◽  
Jiping Tang ◽  
...  

Abstract Background Neuroinflammation plays an important role in pathogenesis of germinal matrix hemorrhage (GMH). Neurotrophin-4 (NT-4) is a member of the neurotrophin family and interacts with the tropomyosin receptor kinase B (TrkB). NT-4 has been shown to confer neuroprotective effects following cerebral ischemia. We aimed to investigate the neuroprotective function of NT-4-TrkB signaling, as well as its downstream signaling cascade phosphatidylinositol-3-kinases (PI3K)/protein kinase B (Akt)/forkhead box protein O1 (FoxO1), following GMH in neonatal rats. Methods GMH was induced by intraparenchymal injection of bacterial collagenase (0.3 U) in P7 rat pups. A total of 163 pups were used in this study. Recombinant human NT-4 was administered intranasally at 1 h after the collagenase injection. The selective TrkB antagonist ANA-12, selective PI3K inhibitor LY294002, and FoxO1 activating CRISPR were administered intracerebroventricularly at 24 h prior to NT-4 treatment to investigate the underlying mechanism. Short-term and long-term neurobehavioral assessments, immunofluorescence staining, Nissl’s staining, and Western blot were performed. Results Expression of phosphorylated TrkB increased after GMH, reaching the peak level at day 3 after hemorrhage. TrkB receptors were observed on neurons, microglia, and astrocytes. The administration of rh-NT-4 induced phosphorylation of TrkB, expression of PI3K, and phosphorylation of Akt. Meanwhile, it decreased FoxO1 and IL-6 levels. Selective inhibition of TrkB/PI3K/Akt signaling in microglia increased the expression levels of FoxO1 and pro-inflammatory cytokines. FoxO1 activating CRISPR increased the expression of IL-6, suggesting that FoxO1 might be a potential inducer of pro-inflammatory factors. These results suggested that PI3K/Akt/FoxO1 signaling may be the downstream pathway of activation of TrkB. The rat pups treated with rh-NT-4 performed better than vehicle-treated animals in both short-term and long-term behavioral tests. Conclusion These data showed that rh-NT-4 reduced the expression levels of pro-inflammatory cytokines, improved neurological function, attenuated neuroinflammation, and thereby mitigated post-hemorrhagic hydrocephalus after GMH by TrkB/PI3K/Akt/FoxO1 pathway. These results indicated that rh-NT-4 could be a promising therapeutic strategy to ameliorate neuroinflammation and hydrocephalus after GMH or other similar brain injuries.

2019 ◽  
Author(s):  
Tianyi Wang ◽  
Junyi Zhang ◽  
Peng Li ◽  
Yan Ding ◽  
Jiping Tang ◽  
...  

Abstract Background: Neuroinflammation plays an important role in pathogenesis of germinal matrix hemorrhage (GMH). Neurotrophin-4 (NT-4) is a member of the neurotrophin family, and it interacts with the tyrosine kinase B (TrkB) receptor. It has been studied that NT-4 has neuroprotective effects following cerebral ischemia. We aimed to investigate the neuroprotective function of NT-4 and it’s high affinity receptor TrkB as well as its downstream mediator phosphatidylinositol-3-kinases (PI3K)/protein kinase B (Akt)/Forkhead box protein O1 (FoxO1) following GMH in neonatal rats, with a specific focus on inflammation. Methods: GMH was induced by intraparenchymal injection of bacterial collagenase (0.3U) in P7 rat pups. A total of 163 seven-day-old pups were used in this study. The recombinant human NT-4 was administered intranasally at 1 hour after the collagenase injection. The selective TrkB antagonist ANA-12, selective PI3K inhibitor LY294002 and FoxO1 activating CRISPR were administered intracerebroventricularly at 24 hours prior to NT-4 treatment to investigate the potential mechanism. Short-and-long-term neurobehavior assessments, immunofluorescence staining, Nissl’s staining and Western blot were performed. Results:The expression of p-TrkB increased after GMH with a peak at day3. The TrkB receptor was expressed by neurons, microglia, and astrocytes. The administration of rh-NT-4 increased phosphorylation of TrkB, expression of PI3K, phosphorylation of Akt and decreased FoxO1, IL-1beta and IL-6 levels. Selective inhibition of TrkB/PI3K/Akt signaling in microglia increased the expression levels of FoxO1 and pro-inflammatory cytokines. The use of FoxO1 activation CRISPR increased the expression of IL-6, suggesting that FoxO1 might potentially induce pro-inflammatory factors. These results demonstrated that PI3K/Akt/FoxO1 may be the downstream pathway of TrkB phosphorylation. The rat pups treated with rh-NT-4 performed better than untreated animals both in short-and-long-term behavior test. Conclusion:These data showed that rh-NT-4 can reduce the expression of pro-inflammatory cytokines, improve neurological function, attenuate neuroinflammation and post-hemorrhagic hydrocephalus after GMH by promoting TrkB/PI3K/Akt/FoxO1 pathway. These results indicated that rh-NT-4 could be a promising therapeutic target to ameliorate neuroinflammation and hydrocephalus after GMH or other similar brain injuries.


2020 ◽  
Author(s):  
Tianyi Wang ◽  
Junyi Zhang ◽  
Peng Li ◽  
Yan Ding ◽  
Jiping Tang ◽  
...  

Abstract Background: Neuroinflammation plays an important role in pathogenesis of germinal matrix hemorrhage (GMH). Neurotrophin-4 (NT-4) is a member of the neurotrophin family, and it interacts with the tyrosine kinase B (TrkB) receptor. It has been studied that NT-4 has neuroprotective effects following cerebral ischemia. We aimed to investigate the neuroprotective function of NT-4 and it’s high affinity receptor TrkB as well as its downstream mediator phosphatidylinositol-3-kinases (PI3K)/protein kinase B (Akt)/Forkhead box protein O1 (FoxO1) following GMH in neonatal rats, with a specific focus on inflammation. Methods: GMH was induced by intraparenchymal injection of bacterial collagenase (0.3U) in P7 rat pups. A total of 163 seven-day-old pups were used in this study. The recombinant human NT-4 was administered intranasally at 1 hour after the collagenase injection. The selective TrkB antagonist ANA-12, selective PI3K inhibitor LY294002 and FoxO1 activating CRISPR were administered intracerebroventricularly at 24 hours prior to NT-4 treatment to investigate the potential mechanism. Short-and-long-term neurobehavior assessments, immunofluorescence staining, Nissl’s staining and Western blot were performed. Results : The expression of p-TrkB increased after GMH with a peak at day3. The TrkB receptor was expressed by neurons, microglia, and astrocytes. The administration of rh-NT-4 increased phosphorylation of TrkB, expression of PI3K, phosphorylation of Akt and decreased FoxO1, IL-1beta and IL-6 levels. Selective inhibition of TrkB/PI3K/Akt signaling in microglia increased the expression levels of FoxO1 and pro-inflammatory cytokines. The use of FoxO1 activation CRISPR increased the expression of IL-6, suggesting that FoxO1 might potentially induce pro-inflammatory factors. These results demonstrated that PI3K/Akt/FoxO1 may be the downstream pathway of TrkB phosphorylation. The rat pups treated with rh-NT-4 performed better than untreated animals both in short-and-long-term behavior test. Conclusion: These data showed that rh-NT-4 can reduce the expression of pro-inflammatory cytokines, improve neurological function, attenuate neuroinflammation and post-hemorrhagic hydrocephalus after GMH by promoting TrkB/PI3K/Akt/FoxO1 pathway. These results indicated that rh-NT-4 could be a promising therapeutic target to ameliorate neuroinflammation and hydrocephalus after GMH or other similar brain injuries.


2020 ◽  
Author(s):  
Tianyi Wang ◽  
Junyi Zhang ◽  
Peng Li ◽  
Yan Ding ◽  
Jiping Tang ◽  
...  

Abstract Background: Neuroinflammation plays an important role in pathogenesis of germinal matrix hemorrhage (GMH). Neurotrophin-4 (NT-4) is a member of the neurotrophin family, and it interacts with the tyrosine kinase B (TrkB) receptor. It has been studied that NT-4 has neuroprotective effects following cerebral ischemia. We aimed to investigate the neuroprotective function of NT-4 and it’s high affinity receptor TrkB as well as its downstream mediator phosphatidylinositol-3-kinases (PI3K)/protein kinase B (Akt)/Forkhead box protein O1 (FoxO1) following GMH in neonatal rats, with a specific focus on inflammation. Methods: GMH was induced by intraparenchymal injection of bacterial collagenase (0.3U) in P7 rat pups. A total of 163 seven-day-old pups were used in this study. The recombinant human NT-4 was administered intranasally at 1 hour after the collagenase injection. The selective TrkB antagonist ANA-12, selective PI3K inhibitor LY294002 and FoxO1 activating CRISPR were administered intracerebroventricularly at 24 hours prior to NT-4 treatment to investigate the potential mechanism. Short-and-long-term neurobehavior assessments, immunofluorescence staining, Nissl’s staining and Western blot were performed. Results : The expression of p-TrkB increased after GMH with a peak at day3. The TrkB receptor was expressed by neurons, microglia, and astrocytes. The administration of rh-NT-4 increased phosphorylation of TrkB, expression of PI3K, phosphorylation of Akt and decreased FoxO1, IL-1beta and IL-6 levels. Selective inhibition of TrkB/PI3K/Akt signaling in microglia increased the expression levels of FoxO1 and pro-inflammatory cytokines. The use of FoxO1 activation CRISPR increased the expression of IL-6, suggesting that FoxO1 might potentially induce pro-inflammatory factors. These results demonstrated that PI3K/Akt/FoxO1 may be the downstream pathway of TrkB phosphorylation. The rat pups treated with rh-NT-4 performed better than untreated animals both in short-and-long-term behavior test. Conclusion: These data showed that rh-NT-4 can reduce the expression of pro-inflammatory cytokines, improve neurological function, attenuate neuroinflammation and post-hemorrhagic hydrocephalus after GMH by promoting TrkB/PI3K/Akt/FoxO1 pathway. These results indicated that rh-NT-4 could be a promising therapeutic target to ameliorate neuroinflammation and hydrocephalus after GMH or other similar brain injuries.


2016 ◽  
Vol 37 (9) ◽  
pp. 3135-3149 ◽  
Author(s):  
Damon Klebe ◽  
Jerry J Flores ◽  
Devin W McBride ◽  
Paul R Krafft ◽  
William B Rolland ◽  
...  

We aim to determine if direct thrombin inhibition by dabigatran will improve long-term brain morphological and neurofunctional outcomes and if potential therapeutic effects are dependent upon reduced PAR-1 stimulation and consequent mTOR activation. Germinal matrix haemorrhage was induced by stereotaxically injecting 0.3 U type VII-S collagenase into the germinal matrix of P7 rat pups. Animals were divided into five groups: sham, vehicle (5% DMSO), dabigatran intraperitoneal, dabigatran intraperitoneal + TFLLR-NH2 (PAR-1 agonist) intranasal, SCH79797 (PAR-1 antagonist) intraperitoneal, and dabigatran intranasal. Neurofunctional outcomes were determined by Morris water maze, rotarod, and foot fault evaluations at three weeks. Brain morphological outcomes were determined by histological Nissl staining at four weeks. Expression levels of p-mTOR/p-p70s6k at three days and vitronectin/fibronectin at 28 days were quantified. Intranasal and intraperitoneal dabigatran promoted long-term neurofunctional recovery, improved brain morphological outcomes, and reduced intracranial pressure at four weeks after GMH. PAR-1 stimulation tended to reverse dabigatran's effects on post-haemorrhagic hydrocephalus development. Dabigatran also reduced expression of short-term p-mTOR and long-term extracellular matrix proteins, which tended to be reversed by PAR-1 agonist co-administration. PAR-1 inhibition alone, however, did not achieve the same therapeutic effects as dabigatran administration.


2021 ◽  
Author(s):  
Olga Cvijanović Peloza ◽  
Sandra Pavičić Žeželj ◽  
Gordana Kenđel Jovanović ◽  
Ivana Pavičić ◽  
Ana Terezija Jerbić Radetić ◽  
...  

Healthy bones are constantly being renewed and proper nutrition is an important factor in this process. Anti-inflammatory diet is designed to improve health and prevent the occurrence and development of chronic diseases associated with inadequate diet. Proper nutrition is based on the anti-inflammatory pyramid and changes in poor eating habits are the long-term strategy for preventing inflammation and chronic diseases. Inflammatory factors from food may play a role in the development of osteoporosis and an anti-inflammatory diet may be a way to control and reduce long-term inflammation and prevent bone loss. Pro-inflammatory cytokines from the fat tissue, through activation of the RANKL/RANK/OPG system could intervene with bone metabolism in a way of increased bone loss. Therefore the special attention need to be given to obese patients due to twofold risk, one related to pro-inflammatory cytokines release and the other related to the deprivation of the vitamin D in the fat tissue.


Stroke ◽  
2014 ◽  
Vol 45 (8) ◽  
pp. 2475-2479 ◽  
Author(s):  
Damon Klebe ◽  
Paul R. Krafft ◽  
Clotilde Hoffmann ◽  
Tim Lekic ◽  
Jerry J. Flores ◽  
...  

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Yang Yu

Phospholipid transfer protein (PLTP) plays important roles in macrophage mediated inflammation. In the current study we observed that endogenous PLTP modulated pro-inflammatory pathways in macrophage. With the presence of LPS, peritoneal derived macrophage (PDM) or bone marrow derived macrophage (BMDM) from PLTP deficient mice (PLTP-/-) expressed significantly higher level of pro-inflammatory cytokines compared with PDM or BMDM from wild-type mice (WT), respectively. LPS induced TNFα expression in PLTP-/- BMDM or PLTP knockdown RAW264.7 were suppressed by (5Z)-7-Oxozeaenol, a TAK1 inhibitor, suggesting PLTP deficiency enhanced the expression of pro-inflammatory cytokines via TAK1-NFκB pathway in macrophage. Furthermore, abundance of TLR4 on the membrane was dramatically increased in BMDM from PLTP-/- compared with WT. In addition, inhibition of ABCA1 by chemical inhibitor, glyburide, did not reduce nuclear levels of active STAT3 of BMDM, which indicated that no autocrine PLTP triggered ABCA1-JAK2-STAT3 pathway in this study. In conclusion, PLTP deficiency or low expression may enhance LPS induced pro-inflammatory cytokines expression via TLR4-TAK1-NFκB pathway in macrophage.


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