scholarly journals Cadherin-12 Regulates Neurite Outgrowth Through the PKA/Rac1/Cdc42 Pathway in Cortical Neurons

Author(s):  
Beibei Guo ◽  
Mengwei Qi ◽  
Shuai Huang ◽  
Run Zhuo ◽  
Wenxue Zhang ◽  
...  

Cadherins play an important role in tissue homeostasis, as they are responsible for cell-cell adhesion during embryogenesis, tissue morphogenesis, and differentiation. In this study, we identified Cadherin-12 (CDH12), which encodes a type II classical cadherin, as a gene that promotes neurite outgrowth in an in vitro model of neurons with differentiated intrinsic growth ability. First, the effects of CDH12 on neurons were evaluated via RNA interference, and the results indicated that the knockdown of CDH12 expression restrained the axon extension of E18 neurons. The transcriptome profile of neurons with or without siCDH12 treatment revealed a set of pathways positively correlated with the effect of CDH12 on neurite outgrowth. We further revealed that CDH12 affected Rac1/Cdc42 phosphorylation in a PKA-dependent manner after testing using H-89 and 8-Bromo-cAMP sodium salt. Moreover, we investigated the expression of CDH12 in the brain, spinal cord, and dorsal root ganglia (DRG) during development using immunofluorescence staining. After that, we explored the effects of CDH12 on neurite outgrowth in vivo. A zebrafish model of CDH12 knockdown was established using the NgAgo-gDNA system, and the vital role of CDH12 in peripheral neurogenesis was determined. In summary, our study is the first to report the effect of CDH12 on axonal extension in vitro and in vivo, and we provide a preliminary explanation for this mechanism.

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Wunan Mi ◽  
Chuyue Wang ◽  
Guang Luo ◽  
Jiehan Li ◽  
Yizheng Zhang ◽  
...  

AbstractIn recent years, many studies have shown that autophagy plays a vital role in the resistance of tumor chemotherapy. However, the interaction between autophagy and cell death has not yet been clarified. In this study, a new specific ERK inhibitor CC90003 was found to suppress colorectal cancer growth by inducing cell death both in vitro and in vivo. Studies have confirmed that higher concentrations of ROS leads to autophagy or cell death. In this research, the role of CC90003-induced ROS was verified. But after inhibiting ROS by two kinds of ROS inhibitors NAC and SFN, the autophagy induced by CC90003 decreased, while cell death strengthened. In parallel, protective autophagy was also induced, while in a p53-dependent manner. After silencing p53 or using the p53 inhibitor PFTα, the autophagy induced by CC90003 was weakened and the rate of cell death increases. Therefore, we confirmed that CC90003 could induce autophagy by activating ROS/p53. Furthermore, in the xenograft mouse model, the effect was obtained remarkably in the combinational treatment group of CC90003 plus CQ, comparing with that of the single treatment groups. In a word, our results demonstrated that targeting ERK leads to cell death and p53/ROS-dependent protective autophagy simultaneously in colorectal cancer, which offers new potential targets for clinical therapy.


2021 ◽  
Vol 9 (2) ◽  
pp. e001364
Author(s):  
Yan Zhang ◽  
Hui Yang ◽  
Jun Zhao ◽  
Ping Wan ◽  
Ye Hu ◽  
...  

BackgroundThe activation of tumor-associated macrophages (TAMs) facilitates the progression of gastric cancer (GC). Cell metabolism reprogramming has been shown to play a vital role in the polarization of TAMs. However, the role of methionine metabolism in function of TAMs remains to be explored.MethodsMonocytes/macrophages were isolated from peripheral blood, tumor tissues or normal tissues from healthy donors or patients with GC. The role of methionine metabolism in the activation of TAMs was evaluated with both in vivo analyses and in vitro experiments. Pharmacological inhibition of the methionine cycle and modulation of key metabolic genes was employed, where molecular and biological analyses were performed.ResultsTAMs have increased methionine cycle activity that are mainly attributed to elevated methionine adenosyltransferase II alpha (MAT2A) levels. MAT2A modulates the activation and maintenance of the phenotype of TAMs and mediates the upregulation of RIP1 by increasing the histone H3K4 methylation (H3K4me3) at its promoter regions.ConclusionsOur data cast light on a novel mechanism by which methionine metabolism regulates the anti-inflammatory functions of monocytes in GC. MAT2A might be a potential therapeutic target for cancer cells as well as TAMs in GC.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Wei Zhang ◽  
Guoyu Yin ◽  
Heping Zhao ◽  
Hanzhi Ling ◽  
Zhen Xie ◽  
...  

AbstractIn inflamed joints, enhanced hyaluronic acid (HA) degradation is closely related to the pathogenesis of rheumatoid arthritis (RA). KIAA1199 has been identified as a hyaladherin that mediates the intracellular degradation of HA, but its extracellular function remains unclear. In this study, we found that the serum and synovial levels of secreted KIAA1199 (sKIAA1199) and low-molecular-weight HA (LMW-HA, MW < 100 kDa) in RA patients were significantly increased, and the positive correlation between them was shown for the first time. Of note, treatment with anti-KIAA1199 mAb effectively alleviated the severity of arthritis and reduced serum LMW-HA levels and cytokine secretion in collagen-induced arthritis (CIA) mice. In vitro, sKIAA1199 was shown to mediate exogenous HA degradation by attaching to the cell membrane of RA fibroblast-like synoviosytes (RA FLS). Furthermore, the HA-degrading activity of sKIAA1199 depended largely on its adhesion to the membrane, which was achieved by its G8 domain binding to ANXA1. In vivo, kiaa1199-KO mice exhibited greater resistance to collagen-induced arthritis. Interestingly, this resistance could be partially reversed by intra-articular injection of vectors encoding full-length KIAA1199 instead of G8-deleted KIAA119 mutant, which further confirmed the indispensable role of G8 domain in KIAA1199 involvement in RA pathological processes. Mechanically, the activation of NF-κB by interleukin-6 (IL-6) through PI3K/Akt signaling is suggested to be the main pathway to induce KIAA1199 expression in RA FLS. In conclusion, our study supported the contribution of sKIAA1199 to RA pathogenesis, providing a new therapeutic target for RA by blocking sKIAA1199-mediated HA degradation.


Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 420
Author(s):  
Su-Jung Hwang ◽  
Ye-Seul Song ◽  
Hyo-Jong Lee

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yorick Janssens ◽  
Nathan Debunne ◽  
Anton De Spiegeleer ◽  
Evelien Wynendaele ◽  
Marta Planas ◽  
...  

AbstractQuorum sensing peptides (QSPs) are bacterial peptides produced by Gram-positive bacteria to communicate with their peers in a cell-density dependent manner. These peptides do not only act as interbacterial communication signals, but can also have effects on the host. Compelling evidence demonstrates the presence of a gut-brain axis and more specifically, the role of the gut microbiota in microglial functioning. The aim of this study is to investigate microglial activating properties of a selected QSP (PapRIV) which is produced by Bacillus cereus species. PapRIV showed in vitro activating properties of BV-2 microglia cells and was able to cross the in vitro Caco-2 cell model and reach the brain. In vivo peptide presence was also demonstrated in mouse plasma. The peptide caused induction of IL-6, TNFα and ROS expression and increased the fraction of ameboid BV-2 microglia cells in an NF-κB dependent manner. Different metabolites were identified in serum, of which the main metabolite still remained active. PapRIV is thus able to cross the gastro-intestinal tract and the blood–brain barrier and shows in vitro activating properties in BV-2 microglia cells, hereby indicating a potential role of this quorum sensing peptide in gut-brain interaction.


2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xinxin Yang ◽  
Haibo Yang ◽  
Fengdi Wu ◽  
Zhipeng Qi ◽  
Jiashuo Li ◽  
...  

Excessive manganese (Mn) can accumulate in the striatum of the brain following overexposure. Oxidative stress is a well-recognized mechanism in Mn-induced neurotoxicity. It has been proven that glutathione (GSH) depletion is a key factor in oxidative damage during Mn exposure. However, no study has focused on the dysfunction of GSH synthesis-induced oxidative stress in the brain during Mn exposure. The objective of the present study was to explore the mechanism of Mn disruption of GSH synthesis via EAAC1 and xCT in vitro and in vivo. Primary neurons and astrocytes were cultured and treated with different doses of Mn to observe the state of cells and levels of GSH and reactive oxygen species (ROS) and measure mRNA and protein expression of EAAC1 and xCT. Mice were randomly divided into seven groups, which received saline, 12.5, 25, and 50 mg/kg MnCl2, 500 mg/kg AAH (EAAC1 inhibitor) + 50 mg/kg MnCl2, 75 mg/kg SSZ (xCT inhibitor) + 50 mg/kg MnCl2, and 100 mg/kg NAC (GSH rescuer) + 50 mg/kg MnCl2 once daily for two weeks. Then, levels of EAAC1, xCT, ROS, GSH, malondialdehyde (MDA), protein sulfhydryl, carbonyl, 8-hydroxy-2-deoxyguanosine (8-OHdG), and morphological and ultrastructural features in the striatum of mice were measured. Mn reduced protein levels, mRNA expression, and immunofluorescence intensity of EAAC1 and xCT. Mn also decreased the level of GSH, sulfhydryl, and increased ROS, MDA, 8-OHdG, and carbonyl in a dose-dependent manner. Injury-related pathological and ultrastructure changes in the striatum of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GSH synthesis through inhibition of EAAC1 and xCT to trigger oxidative damage in the striatum.


2017 ◽  
Vol 43 (5) ◽  
pp. 2074-2087 ◽  
Author(s):  
Liling Yang ◽  
Xiangjun Zhou ◽  
Weijuan Huang ◽  
Qin Fang ◽  
Jianlan Hu ◽  
...  

Background/Aims: Forsythia suspensa Vahl. (Oleaceae) fruits are widely used in traditional Chinese medicine to treat pneumonia, typhoid, dysentery, ulcers and oedema. Antibacterial and anti-inflammatory activities have been reported for phillyrin (PHN), the main ingredient in Forsythia suspensa Vahl fruits, in vitro. However, the underlying mechanisms in vivo remain poorly defined. In this study, we discovered that PHN exerted potent anti-inflammatory effects in lethal LPS-induced neutrophil inflammation by suppressing the MyD88-dependent signalling pathway in zebrafish. Methods: LPS-yolk microinjection was used to induce a lethal LPS-infected zebrafish model. The effect of PHN on the survival of zebrafish challenged with lethal LPS was evaluated using survival analysis. The effect of PHN on neutrophil inflammation grading in vivo was assessed by tracking neutrophils with a transgenic line. The effects of PHN on neutrophil production and migration were analysed by SB+ cell counts during consecutive hours after modelling. Additionally, key cytokines and members of the MyD88 signalling pathway that are involved in inflammatory response were detected using quantitative RT-PCR. To assess gene expression changes during consecutive hours after modelling, the IL-1β, IL-6, TNF-α, MyD88, TRIF, ERK1/2, JNK, IκBa and NF-κB expression levels were measured. Results: PHN could protect zebrafish against a lethal LPS challenge in a dose-dependent manner, as indicated by decreased neutrophil infltration, reduced tissue necrosis and increased survival rates. Up-regulated IL-1β, IL-6 and TNF-α expression also showed the same tendencies of depression by PHN. Critically, PHN significantly inhibited the LPS-induced activation of MyD88, IκBa, and NF-κB but did not affect the expression of ERK1/2 MAPKs or JNK MAPKs in LPS-stimulated zebrafish. Additionally, PHN regulated the MyD88/IκBα/NF-κB signalling pathway by controlling IκBα, IL-1β, IL-6, and TNF-α expression. Conclusion: This study provides a rationale for the clinical application of PHN as an anti-inflammatory agent.


Author(s):  
Jelena Damm ◽  
Joachim Roth ◽  
Rüdiger Gerstberger ◽  
Christoph Rummel

AbstractBackground:Studies with NF-IL6-deficient mice indicate that this transcription factor plays a dual role during systemic inflammation with pro- and anti-inflammatory capacities. Here, we aimed to characterize the role of NF-IL6 specifically within the brain.Methods:In this study, we tested the capacity of short interfering (si) RNA to silence the inflammatory transcription factor nuclear factor-interleukin 6 (NF-IL6) in brain cells underResults:In cells of a mixed neuronal and glial primary culture from the ratConclusions:This approach was, thus, not suitable to characterize the role NF-IL6 in the brain


2021 ◽  
Vol 8 ◽  
Author(s):  
An Liu ◽  
Wenyuan Shi ◽  
Dongdong Lin ◽  
Haihui Ye

C-type allatostatins (C-type ASTs) are a family of structurally related neuropeptides found in a wide range of insects and crustaceans. To date, the C-type allatostatin receptor in crustaceans has not been deorphaned, and little is known about its physiological functions. In this study, we aimed to functionally define a C-type ASTs receptor in the mud crab, Scylla paramamosian. We showed that C-type ASTs receptor can be activated by ScypaAST-C peptide in a dose-independent manner and by ScypaAST-CCC peptide in a dose-dependent manner with an IC50 value of 6.683 nM. Subsequently, in vivo and in vitro experiments were performed to investigate the potential roles of ScypaAST-C and ScypaAST-CCC peptides in the regulation of ecdysone (20E) and methyl farnesoate (MF) biosynthesis. The results indicated that ScypaAST-C inhibited biosynthesis of 20E in the Y-organ, whereas ScypaAST-CCC had no effect on the production of 20E. In addition, qRT-PCR showed that both ScypaAST-C and ScypaAST-CCC significantly decreased the level of expression of the MF biosynthetic enzyme gene in the mandibular organ, suggesting that the two neuropeptides have a negative effect on the MF biosynthesis in mandibular organs. In conclusion, this study provided new insight into the physiological roles of AST-C in inhibiting ecdysone biosynthesis. Furthermore, it was revealed that AST-C family peptides might inhibit MF biosynthesis in crustaceans.


2021 ◽  
Vol 12 ◽  
Author(s):  
Luping Zhang ◽  
Dengyuan Zhou ◽  
Qiuyan Li ◽  
Shuo Zhu ◽  
Muhammad Imran ◽  
...  

Flaviviruses are the major emerging arthropod-borne pathogens globally. However, there is still no practical anti-flavivirus approach. Therefore, existing and emerging flaviviruses desperately need active broad-spectrum drugs. In the present study, the antiviral effect of steroidal dehydroepiandrosterone (DHEA) and 23 synthetic derivatives against flaviviruses such as Japanese encephalitis virus (JEV), Zika virus (ZIKV), and Dengue virus (DENV) were appraised by examining the characteristics of virus infection both in vitro and in vivo. Our results revealed that AV1003, AV1004 and AV1017 were the most potent inhibitors of flavivirus propagation in cells. They mainly suppress the viral infection in the post-invasion stage in a dose-dependent manner. Furthermore, orally administered compound AV1004 protected mice from lethal JEV infection by increasing the survival rate and reducing the viral load in the brain of infected mice. These results indicate that the compound AV1004 might be a potential therapeutic drug against JEV infection. These DHEA derivatives may provide lead scaffolds for further design and synthesis of potential anti-flavivirus potential drugs.


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