Astrocyte-neuron communication mediated by the Notch signaling pathway:focusing on glutamate transport and synaptic plasticity

Maintaining glutamate homeostasis after hypoxic ischemia is important for synaptic function and neural cell activity,and regulation of glutamate transport between astrocyte and neuron is one of the important modalities for reducing glutamate accumulation.However,further research is needed to investigate the dynamic changes in and molecular mechanisms of glutamate transport and the effects of glutamate transport on synapses.The aim of this study was to investigate the regulatory mechanisms underlying Notch pathway mediation of glutamate transport and synaptic plasticity.In this study,Yorkshire neonatal pigs(male,age 3 days,weight 1.0–1.5 kg,n=48)were randomly divided into control(sham surgery group)and five hypoxic ischemia subgroups,according to different recovery time,which were then further subdivided into subgroups treated with dimethyl sulfoxide or a Notch pathway inhibitor(N-[N-(3,5-difluorophenacetyl-l-alanyl)]-S-phenylglycine t-butyl ester).Once the model was established,immunohistochemistry,immunofluorescence staining,and western blot analyses of Notch pathway-related proteins,synaptophysin,and glutamate transporter were performed.Moreover,synapse microstructure was observed by transmission electron microscopy.At the early stage(6–12 hours after hypoxic ischemia)of hypoxic ischemic injury,expression of glutamate transporter excitatory amino acid transporter-2 and synaptophysin was downregulated,the number of synaptic vesicles was reduced,and synaptic swelling was observed;at 12–24 hours after hypoxic ischemia,the Notch pathway was activated,excitatory amino acid transporter-2 and synaptophysin expression was increased,and the number of synaptic vesicles was slightly increased.Excitatory amino acid transporter-2 and synaptophysin expression decreased after treatment with the Notch pathway inhibitor.This suggests that glutamate transport in astrocytes-neurons after hypoxic ischemic injury is regulated by the Notch pathway and affects vesicle release and synaptic plasticity through the expression of synaptophysin.

Activation of the Notch signaling pathway promotes neurovascular repair after traumatic brain injury

The Notch signaling pathway plays a key role in angiogenesis and endothelial cell formation, but it remains unclear whether it is involved in vascular repair by endothelial progenitor cells after traumatic brain injury. Therefore, in the present study, we controlled the Notch signaling pathway using overexpression and knockdown constructs. Activation of the Notch signaling pathway by Notch1 or Jagged1 overexpression enhanced the migration, invasiveness and angiogenic ability of endothelial progenitor cells. Suppression of the Notch signaling pathway with Notch1 or Jagged1 si RNAs reduced the migratory capacity, invasiveness and angiogenic ability of endothelial progenitor cells. Activation of the Notch signaling pathway in vivo in a rat model of mild traumatic brain injury promoted neurovascular repair. These findings suggest that the activation of the Notch signaling pathway promotes blood vessel formation and tissue repair after brain trauma.

Scalp acupuncture Yikang therapy on Baihui(GV20),Sishencong(EX-HN1),Zhisanzhen,Niesanzhen improves neurobehavior in young rats with cerebral palsy through Notch signaling pathway

OBJECTIVE:To investigate the efficacy of scalp acupuncture Yikang therapy on Baihui(GV20),Sishencong(EX-HN1),Zhisanzhen,Niesanzhen,on neurobehavior in young rats with cerebral palsy based on Notch signaling pathway.METHODS:Thirty 7-day-old rats were randomly divided into sham,model and acupuncture,10 rats in each group.The cerebral palsy model was established by the accepted modeling method,the acupuncture group selected"Baihui(GV20)","Sishencong(EX-HN1)","Zhisanzhen"and"Niesanzhen"for intervention 24 h after the model was made.The body masses were recorded before and after the treatment,respectively.After the intervention,the rats were subjected to suspension experiment,slope experiment,tactile stimulation experiment and Morris water maze experiment.After the end of the experiment,the morphological changes of hippocampal histology were observed by hematoxylineosin(HE)staining under light microscope,and the expression of Notch1,Notch3 and Hes5 were detected by Western blot and quantitative real-time polymerase chain reaction(PCR).RESULTS:The changes in body mass of the rats in each group were different;in behavioral experiments,compared with the sham,the suspension time of the model was shortened,the slope experiment,tactile stimulation experiment,and escape latency time were prolonged,and the number of platform crossing was reduced in the model,compared with the model,the suspension time of the acupuncture was prolonged,the slope experiment,tactile stimulation experiment,and escape latency time were shortened,and the number of platform crossing times was increased;HE staining showed severe hippocampal damage in the model and reduced hippocampal damage in the acupuncture.Western Blot and real-time fluorescence quantitative PCR showed that the expression of Notch1,Notch3 and Hes5 were increased in the model and the expression of Notch1,Notch3,Hes5 in acupuncture were decreased.CONCLUSIONS:Scalp acupuncture Yikang therapy may improve neurobehavior and reduce brain injury in rats with cerebral palsy by downregulating the expression of Notch1,Notch3,and Hes5.

Effects of the Nocth signaling pathway on expression of inflammatory factors and transforming growth factors in diabetic foot ulcers

Objective:persistent hyperinflammation is an important reason for the development of diabetic foot ulcer.Notch signaling is an important signaling pathway involved in the inflammatory response and cell proliferation in diabetic foot ulcer rats.This paper aims to explore the effect of Notch signaling on inflammatory factors,chemokines and growth factors through the intervention of Notch signaling in diabetic foot ulcer rats.Methods:the experimental model was made by using high-fat feed combined with streptozotocin(STZ)to cause diabetes,and the experimental model of diabetic foot ulcer was established by constant temperature and constant pressure scald apparatus.The normal ulcer model was used as a control.The intervention controls of the experimental model included normal saline,western medicine growth factor,Notch agonist Jagged1,Notch signaling inhibitor ly-411575,and the intervention of traditional Chinese medicine Zizhu ointment for 7 days.Serum il-1,il-6,TNF-radiation,and il-17 were detected by ELISA.Real-time PCR was used to detect the inflammatory factors,chemokines,and growth factors associated with Notch signaling in wound tissues:tnf-uum,il-1,il-6,il-17,interleukin-8,ip-10,McP-1,TGF-uum,TGF-livelihood.Results:serum levels of il-1,il-6,TNF-radiation and il-17 in diabetic foot ulcer rats were significantly higher than that in normal ulcer rats.The contents of il-1,il-6,TNF-radiation and il-17a in ly-411575 group and Zizhu ointment group were significantly reduced.Real-time PCR results of wound tissue showed that the levels of inflammatory cytokines il-1,il-6,TNF-radiation,il-17 and chemokines ip-10,il-8 and McP-1 in the wound tissue of diabetic foot ulcer rat model were significantly higher than that of normal ulcer model,and the levels of growth factor TGF-exposure were lower than that of normal ulcer model.LY-411575 significantly reduced il-1,il-6,TNF-maxima,il-17,and the chemokines ip-10,il-8,and McP-1 in diabetic foot ulcer rats,and reduced the expression of TGF-,TGF-earth.Jagged1 can increase the expression of TGF--,TGF---,suggesting that inhibition of the Notch signaling pathway can reduce the expression of the inflammatory factors il-1,il-6,TNF--,il-17a,il-8,and the growth factors TGF--,TGF---.Zizhu ointment can reduce the levels of il-1,il-6,TNF-benand,il-17,and the chemokines ip-10,il-8,and McP-1 on the wound surface of diabetic foot rats,and improve the expression of TGF-benand TGF-SUNS.Ly-411575 inhibited the expression of TGF-bento and TGF-promoting of Zizhu ointment.Conclusion:the expression of inflammatory cytokines and chemokines was higher and the expression of growth factors was lower in diabetic foot ulcer rats than in normal ulcer rats.Inhibition of Notch signaling pathway can reduce the expression of inflammatory factors,chemokines and growth factors in experimental model rats,and Notch signaling pathway can promote inflammation and cell proliferation.Zizhu ointment can reduce the levels of inflammatory cytokines and chemokines in diabetic foot ulcer rats,improve the expression of growth factors,and reduce wound inflammation,which may be related to the inhibition of Nocth signal expression.

Changes and correlation of inflammatory polarization and Notch pathway in rats with adjuvant arthritis

Objective:To investigate the relationship between inflammatory polarization and Notch pathway in rats with adjuvant arthritis.Methods:Twelve rats were randomly divided into normal(NC)group(n=6)and model(MC)group(n=6).In the model group,complete Freund's adjuvant(0.1ml/rat)was injected into the right hindfoot to induce inflammation.On the 12th day after inflammation,the changes of plantar swelling degree(E)and arthritis index(AI)were observed,and the expressions of inflammatory polarization markers CD68 and CD206 in peripheral blood were detected by flow cytometry.PCR was used to detect the expression of factors related to Notch signal pathway in peripheral blood.Results:Compared with the normal group,the expression of E,AI,CD68,Notch2,Notch3,Notch4 and Delta1 in the model group increased significantly,while the expression of CD206,Notch1,Jagged1 and Jagged2 decreased(P<0.01or P<0.05).The results showed that CD68,toe swelling degree and arthritis index were negatively correlated with Notch1,Jagged1 and Jagged2,CD68,toe swelling degree and arthritis index were positively correlated with Notch2,Notch4 and Delta1,CD206 was positively correlated with Notch1 and Jagged1,Jagged2 and CD206 was negatively correlated with Notch2,Notch4 and Delta1.Conclusion:Notch signal pathway may promote the occurrence and development of AA by regulating inflammatory polarization of macrophages.

Notch signalling pathway in development of cholangiocarcinoma

Cholangiocarcinoma(CCA)comprises of extra-hepatic cholangiocarcinoma and intrahepatic cholangiocarcinoma cancers as a result of inflammation of epithelium cell lining of the bile duct.The incidence rate is increasing dramatically worldwide with highest rates in Eastern and South Asian regions.Major risk factors involve chronic damage and inflammation of bile duct epithelium from primary sclerosing cholangitis,chronic hepatitis virus infection,gallstones and liver fluke infection.Various genetic variants have also been identified and as CCA develops on the background of biliary inflammation,diverse range of molecular mechanisms are involved in its progression.Among these,the Notch signalling pathway acts as a major driver of cholangiocarcinogenesis and its components(receptors,ligands and downstream signalling molecules)represent a promising therapeutic targets.Gamma-Secretase Inhibitors have been recognized in inhibiting the Notch pathway efficiently.A comprehensive knowledge of the molecular pathways activated by the Notch signalling cascade as well as its functional crosstalk with other signalling pathways provide better approach in developing innovative therapies against CCA.

In vivo study of the effect of anlotinib on the stemness of the lenvatinib-resistant hepatocellular carcinoma cells and the underlying mechanisms

Background:In vivo experiments were conducted to examine the effects of the targeted drug anlotinib on the stemness of hepatocellular carcinoma(HCC)cells and lenvatinib-resistant liver cancer cells and to explore the underlying molecular mechanisms.Methods:A subcutaneous xenograft model of Hep3B-derived HCC was established in nude mice,which were randomly divided into 2 groups(n=5 males per group):(1)intragastric administration of anlotinib(0.4 mg/kg)and(2)intragastric administration of normal saline.We constructed lenvatinib-resistant cell lines and randomly divided the mice into 3 groups(n=5 males per group):(1)intragastric administration of anlotinib,(2)intragastric administration of lenvatinib,and(3)intragastric administration of normal saline.After 2 weeks of treatment,tumor tissues were harvested,and mRNA and proteins were isolated from the tissues.Changes in the expression of cancer stemness markers(epithelial cell adhesion molecule[EpCAM],CD13,CD90,aldehyde dehydrogenase 1[ALDH1],CD44,and CD45),totipotency factors(sex-determining region Y-box 2[Sox2],Nanog,octamer-binding transcription factor 4[Oct4]),and genes related to the Notch signaling pathway were examined.Results:Compared with that in the control group,tumor size and weight were reduced in nude mice treated with anlotinib.These differences were statistically significant in both the types of nude mice.Anlotinib affected stemness markers and totipotency factors by downregulating the expression of CD133,CD90,and G-protein–coupled receptor 5(LGR5)and upregulating the expression of intercellular adhesion molecule 1(ICAM-1)and Sox2.In addition,lenvatinib-resistant cell lines increased Notch signaling pathway,whereas anlotinib inhibited Notch signaling pathway.Conclusions:The antitumor effect of anlotinib on HCC and lenvatinib-resistant HCC cellsmay occur through inhibition of the Notch signaling pathway.Anlotinib may be the drug of choice for sequential therapy in lenvatinib-resistant liver cancer.

Effects of JAG-1 on the Proliferation and Migration of Gastric Adenocarcinoma Cells after TRAIP Knockout

[Objectives]To study the effects of JAG-1 on silencing TRAIP(tumor necrosis factor receptor associated factor interaction protein)after regulating Notch signaling pathway on the proliferation and migration of gastric adenocarcinoma cells.[Methods]Gastric adenocarcinoma cells were categorized into si-NC+DMSO(control+DMSO),si-TRAIP#1+DMSO(transfected with TRAIP+DMSO),si-NC+JAG-1(control+JAG-1),and si-TRAIP#1+JAG-1(transfected with TRAIP+JAG-1),and the proliferation of the cells was detected by CCK-8 assay and plate colony formation assay.Transwell assay was used to detect cell migration,and Western blot was adopted to detect the expression of proliferation-associated protein CyclinD1,migration-associated protein MMP2,and key proteins of Notch signaling pathway Notch1,Hes1 and Jagged1.[Results]Compared with siTRAIP#1+DMSO,the gastric adenocarcinoma cells in si-TRAIP#1+JAG-1 group showed increased proliferation and migration(P<0.05),and there was a significant increase in the expression of CyclinD1,MMP2,Notch1,Hes1,and Jagged1(P<0.05).[Conclusions]After TRAIP knockdown,JAG-1 increased not only the proliferation and migration ability of gastric adenocarcinoma cells,but also the expression of key proteins of Notch signaling pathway Notch1,Hes1,and Jagged1.

Aerobic exercise combined with huwentoxin-I mitigates chronic cerebral ischemia injury

Ca^(2+) channel blockers have been shown to protect neurons from ischemia, and aerobic exercise has significant protective effects on a variety of chronic diseases. The present study injected huwentoxin-I(HWTX-I), a spider peptide toxin that blocks Ca^(2+) channels, into the caudal vein of a chronic cerebral ischemia mouse model, once every 2 days, for a total of 15 injections. During this time, a subgroup of mice was subjected to treadmill exercise for 5 weeks. Results showed amelioration of cortical injury and improved neurological function in mice with chronic cerebral ischemia in the HWTX-I + aerobic exercise group. The combined effects of HWTX-I and exercise were superior to HWTX-I or aerobic exercise alone. HWTX-I effectively activated the Notch signal transduction pathway in brain tissue. Aerobic exercise up-regulated synaptophysin m RNA expression. These results demonstrated that aerobic exercise, in combination with HWTX-I, effectively relieved neuronal injury induced by chronic cerebral ischemia via the Notch signaling pathway and promoting synaptic regeneration.

Novel molecular targets in hepatocellular carcinoma

Globally,hepatocellular carcinoma(HCC)is a leading cause of cancer and cancerrelated deaths.The therapeutic efficacy of locoregional and systemic treatment in patients with advanced HCC remains low,which results in a poor prognosis.The development of sorafenib for the treatment of HCC has resulted in a new era of molecular targeted therapy for this disease.However,the median overall survival was reported to be barely higher in the sorafenib treatment group than in the control group.Hence,in this review we describe the importance of developing more effective targeted therapies for the management of advanced HCC.Recent investigations of molecular signaling pathways in several cancers have provided some insights into developing molecular therapies that target critical members of these signaling pathways.Proteins involved in the Hedgehog and Notch signaling pathways,Polo-like kinase 1,arginine,histone deacetylases and Glypican-3 can be potential targets in the treatment of HCC.Monotherapy has limited therapeutic efficacy due to the development of inhibitory feedback mechanisms and induction of chemoresistance.Thus,emphasis is now on the development of personalized and combination molecular targeted therapies that can serve as ideal therapeutic strategies for improved management of HCC.

Comprehensive characterization of CRC with germline mutations reveals a distinct somatic mutational landscape and elevated cancer risk in the Chinese population

Objective:Hereditary colorectal cancer(CRC)accounts for approximately 5%–10%of all CRC cases.The full profile of CRC-related germline mutations and the corresponding somatic mutational profile have not been fully determined in the Chinese population.Methods:We performed the first population study investigating the germline mutation status in more than 1,000(n=1,923)Chinese patients with CRC and examined their relationship with the somatic mutational landscape.Germline alterations were examined with a 58-gene next-generation sequencing panel,and somatic alterations were examined with a 605-gene panel.Results:A total of 92 pathogenic(P)mutations were identified in 85 patients,and 81 likely pathogenic(LP)germline mutations were identified in 62 patients,accounting for 7.6%(147/1,923)of all patients.MSH2 and APC was the most mutated gene in the Lynch syndrome and non-Lynch syndrome groups,respectively.Patients with P/LP mutations had a significantly higher ratio of microsatellite instability,highly deficient mismatch repair,family history of CRC,and lower age.The somatic mutational landscape revealed a significantly higher mutational frequency in the P group and a trend toward higher copy number variations in the non-P group.The Lynch syndrome group had a significantly higher mutational frequency and tumor mutational burden than the nonLynch syndrome group.Clustering analysis revealed that the Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Population risk analysis indicated that the overall odds ratio was 11.13(95%CI:8.289–15.44)for the P group and 20.68(95%CI:12.89–33.18)for the LP group.Conclusions:Distinct features were revealed in Chinese patients with CRC with germline mutations.The Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Patients with P/LP germline mutations exhibited higher CRC risk.

Alagille syndrome associated with total anomalous pulmonary venous connection and severe xanthomas:A case report

BACKGROUND Alagille syndrome(ALGS)is an autosomal dominant genetic disorder caused by mutations in the JAG1 or NOTCH2 gene.It is characterized by decreased intrahepatic bile ducts associated with a variety of abnormalities in many other organ systems,such as the cardiovascular,skeletal,and urinary systems.CASE SUMMARY We report a rare case of ALGS.A 1-month-old male infant presented with sustained jaundice and had a rare congenital heart disease:Total anomalous pulmonary venous connection(TAPVC).Sustained jaundice,particularly with cardiac murmur,caught our attention.Laboratory tests revealed elevated levels of alanine aminotransferase,aspartate aminotransferase,gamma-glutamyl transpeptidase,total bilirubin,and total bile acids,indicating serious intrahepatic cholestasis.Imaging confirmed the presence of butterfly vertebra at the seventh thoracic vertebra.This suggested ALGS,which was confirmed by genetic testing with a c.3197dupC mutation in the JAG1 gene.Ursodiol was administered immediately after confirmation of the diagnosis,and cardiac surgery was performed when the patient was 1.5 month old.He recovered well after treatment and was discharged at the age of 3 mo.At the age of two years,the patient returned to our clinic because multiple cutaneous nodules with xanthomas appeared,and their size and number increased over time.CONCLUSION We report a unique case of ALGS associated with TAPVC and severe xanthomas.This study has enriched the clinical manifestations of ALGS and emphasized the association between JAG1 gene and TAPVC.

Application of silk fibroin coatings for biomaterial surface modification:a silk road for biomedicine

Silk fibroin(SF)as a natural biopolymer has become a popular material for biomedical applications due to its minimal immunogenicity,tunable biodegradability,and high biocompatibility.Nowadays,various techniques have been developed for the applications of SF in bioengineering.Most of the literature reviews focus on the SF-based biomaterials and their different forms of applications such as films,hydrogels,and scaffolds.SF is also valuable as a coating on other substrate materials for biomedicine;however,there are few reviews related to SF-coated biomaterials.Thus,in this review,we focused on the surface modification of biomaterials using SF coatings,demonstrated their various preparation methods on substrate materials,and introduced the latest procedures.The diverse applications of SF coatings for biomedicine are discussed,including bone,ligament,skin,mucosa,and nerve regeneration,and dental implant surface modification.SF coating is conducive to inducing cell adhesion and migration,promoting hydroxyapatite(HA)deposition and matrix mineralization,and inhibiting the Notch signaling pathway,making it a promising strategy for bone regeneration.In addition,SF-coated composite scaffolds can be considered prospective candidates for ligament regeneration after injury.SF coating has been proven to enhance the mechanical properties of the substrate material,and render integral stability to the dressing material during the regeneration of skin and mucosa.Moreover,SF coating is a potential strategy to accelerate nerve regeneration due to its dielectric properties,mechanical flexibility,and angiogenesis promotion effect.In addition,SF coating is an effective and popular means for dental implant surface modification to promote osteogenesis around implants made of different materials.Thus,this review can be of great benefit for further improvements in SF-coated biomaterials,and will undoubtedly contribute to clinical transformation in the future.