c-Jun Expression Research Articles

Nur77 Mediates Anaphylaxis by Regulating miR-21a.

Nur77 belongs to the NR4A subfamily of orphan nuclear hormone receptors. It has been shown to play important roles in metabolism, cancer progression, cellular differentiation, and the regulation of immune process. However, there has yet to be research reporting on the role of Nur77 in allergic inflammations such as anaphylaxis. This study aimed to identify molecules that could mediate allergic inflammations. To this end, we performed RNA sequencing analysis employing bone marrow-derived mast cells (BMMCs). Antigen (DNP-HSA) stimulation increased the expression levels of transcription factors such as Nr4a3 (NOR1), Nr4a1 (Nur77), and Nr4a2 (Nurr1). We focused our study on Nur77. Antigen stimulation increased the expression of Nur77 in a time- and dose-dependent manner in rat basophilic leukemia cells (RBL2H3). The downregulation of Nur77 prevented both antigen-induced increase in β-hexosaminidase activity as well as hallmarks of allergic reactions such as HDAC3, COX2, and MCP1 in RBL2H3 cells. Nur77 was necessary for both passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis (PSA). TargetScan analysis predicted that miR-21a would be a negative regulator of Nur77. miR-21a mimic negatively regulated PCA and PSA by inhibiting the hallmarks of allergic reactions. ChIP assays showed that c-JUN could bind to the promoter sequences of Nur77. Antigen stimulation increased the expression of c-JUN in RBL2H3 cells. Altogether, our findings demonstrate the regulatory role played by Nur77-miR-21a loop in allergic inflammations such as anaphylaxis, making this the first report to present the role played by Nur77 in an allergic inflammation. Our results suggest that Nur77 and miR-21 might serve as targets for developing anti-allergy drugs.

Mode of delivery alters sensitivity to thermal and chemical stimuli in adult rats: An experimental study.

The mode of delivery might prompt a long-lasting alteration in physiological and behavioral responsiveness in offspring. This study was intended to evaluate if the mode of delivery could alter sensitivity to thermal and chemical stimuli in female rats. 56 adult female Wistar rats (200-220 gr) that were born by vaginal or cesarean section (C-section) were used (n = 28/each). Inflammatory pain was induced by subcutaneous injection of formalin into the hind paw. The thermal nociceptive threshold was determined by tail-flick and hot plate tests. Besides, the Western blot test was used to evaluate the spinal cord levels of c-Fos and c-Jun proteins. Formalin-induced inflammation was significantly decreased in C-section group as compared to vaginally born rats (p 0.001). The baseline nociceptive threshed and morphine-induced analgesia were significantly increased in C-section groups in comparison to vaginally born rats. In addition, the levels of c-Fos and c-Jun proteins were significantly decreased in the spinal cord of C-section rats as compared to vaginally born animals (p 0.01). Morphine treatment could decrease the expression of c-Fos and c-Jun in the C-section group (p 0.05). Overall, C-section rats showed lower spinal nociceptive processing and neuronal activity later in life, compared to the vaginal born rats.

The miR-221/222 regulates the ID1 gene expression through PTEN, c-JUN and ARF4 mediators to control cell proliferation

Objective: To explore the effect of miR-221/222 on cell proliferation and regulation of inhibitor of differentiation1 (ID1) expression concerning the value of miR-221/22 in cancer diagnosis, prognosis, or therapeutic use. Methods: Embryonic cell line (HEK293), breast cancer cell line (MCF7), and lymphoblast cell line (U937) were employed to investigate cell proliferation in the presence or absence of miR-221/222 using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. The relation of miR-221/222 and expression of the ID1 gene was monitored via luciferase activity and real-time PCR. Quantitative PCR was used to detect the effect of miR-221/222 on the expression of cellular proteins, c-JUN, ARF4, and PTEN. Results: The miR-221/222 significantly increased the expression level of the ID1 gene in MCF7 and U937 cell lines but downregulation of the ID1 gene was revealed for transfected HEK293 cells. Level of the ID1 mRNA showed that miR-221/222 regulated the ID1 gene expression at the transcriptional level. Moreover, miR-221/222 enhanced the cellular proteins, ARF4 and c-JUN, and expression in MCF7 and U937, while inhibiting them in HEK293. These findings indicated that the effect of miR-221/222 on ARF4 and c-JUN expression in HEK293 may be mediated by different pathways from MCF7 and U937. Conclusions: Increasing levels of miR-221/222 expression are correlated with cell proliferation and the regulation of ID1 expression. ID1 regulation is a complex process and miR-221/222 may regulate its expression via c-JUN and ARF4. The value of miR-221/22 in cancer diagnosis, prognosis, or therapeutic use may be cancer type dependent.

HO-1 attenuates testicular ischaemia/reperfusion injury by activating the phosphorylated C-jun-miR-221/222-TOX pathway

AimsHeme oxygenase (HO-1) affords protection against ischaemia/reperfusion (I/R) injury; however, its effects on testicular I/R injury remain poorly explored. Herein, we aimed to examine the effects of HO-1 on testicular I/R injury and elucidate the underlying mechanism. MethodsUsing the TALEN technique, we knocked out the HO-1 gene from rats. In vivo: Thirty hmox+/+ and 30 hmox−/− rats were randomly assigned to six groups: sham-operated (sham), I/R (the left testicle torsion/detorsion) 0 d,I/R 1d, I/R 3d, I/R 7d and I/R 28d. In vitro: GC-1 were suffered from: control,H/R (oxygen-deprivation/reoxygenation),H/R + HO-1 siRNA,H/R + c-Jun siRNA or H/R + HO-1 siRNA + c-jun.We performed immunofluorescence and immunohistochemistry experiments to detect HO-1 nuclear translocation. Flow cytometry was used to detect cell apoptosis and analyse the cell cycle. High-resolution miRNA, mRNA sequencing, reverse transcription-quantitative PCR, and western blotting were performed to identify testicular I/R injury-related genes strongly conserved in HO-1 knockout rats. A double luciferase reporter assay was performed to verify the relationship between C-jun and miR-221/222. Main findingsIn vivo, HO-1 improved the pathological damage induced by testicular I/R. In GC-1 cells, we confirmed the nuclear translocation of HO-1 and its protective effect against hypoxia/reoxygenation (H/R) damage. Accordingly, HO-1 protein itself, rather than heme metabolites, might play a key role in testicular I/R. Gene sequencing was performed to screen for miR221/222 and its downstream gene, thymocyte selection-associated high mobility group box (TOX). HO-1 increased c-Jun phosphorylation in the H/R group, knocked down c-Jun in GC-1 cells, and decreased miR-221/222 expression. Inhibition of HO-1 expression decreased the expression of c-Jun and miR-221/222, which was rescued by adding c-Jun. Dual-luciferase reporter assay confirmed the interaction between c-Jun and miR-221/222. ConclusionsHO-1 could exert a protective effect against testicular I/R via the phosphorylated c-Jun-miR-221/222-TOX pathway.

ZBTB7B is a permissive regulator of hepatocellular carcinoma initiation by repressing c-Jun expression and function

Hepatocarcinogenesis is a multi-step process. However, the regulators of hepatocellular carcinoma (HCC) initiation are understudied. Adult liver-specific gene expression was globally downregulated in HCC. We hypothesize that adult liver-specific genes, especially adult liver-enriched transcription factors may exert tumor-suppressive functions in HCC. In this study, we identify ZBTB7B, an adult liver-enriched transcription factor as a permissive regulator of HCC initiation. ZBTB7B is highly expressed in hepatocytes in adult livers, compared to fetal livers. To evaluate the functions of ZBTB7B in hepatocarcinogenesis, we performed hepatocyte-specific ZBTB7B knockout in hydrodynamic oncogene transfer-induced mouse liver cancer models. Hepatocyte-specific knockout of ZBTB7B promotes activated Akt and N-Ras-induced HCC development. Moreover, ZBTB7B deficiency sensitizes hepatocytes to a single oncogene Akt-induced oncogenic transformation and HCC initiation, which is otherwise incompetent in inducing HCC. ZBTB7B deficiency accelerates HCC initiation by down-regulating adult liver-specific gene expression and priming livers to a fetal-like state. The molecular mechanism underlying ZBTB7B functions in hepatocytes was investigated by integrated transcriptomic, phosphoproteomic, and chromatin immunoprecipitation-sequencing analyses. Integrative multi-omics analyses identify c-Jun as the core signaling node in ZBTB7B-deficient liver cancer initiation. c-Jun is a direct target of ZBTB7B essential to accelerated liver cancer initiation in ZBTB7B-deficient livers. Knockdown of c-Jun expression or dominant negative c-Jun expression delays HCC development in ZBTB7B-deficient livers. In addition, ZBTB7B competes with c-Jun for chromatin binding. Ectopic ZBTB7B expression attenuates the tumor-promoting functions of c-Jun. Expression of ZBTB7B signature, composed of 140 genes co-regulated by ZBTB7B and c-Jun, is significantly downregulated in early-stage HCCs compared to adjacent normal tissues, correlates to liver-specific gene expression, and is associated with good prognosis in human HCC. Thus, ZBTB7B functions as a permissive regulator of HCC initiation by directly regulating c-Jun expression and function.

The Immune-Stimulating and Anti-Diabetic Effects of Allium hookeri Leaves Grown in a Plant Factory with Artificial Lights in Immunosuppressed Obese C57BL/6 Mice.

We investigated the immune-stimulating and anti-diabetic effects of Allium hookeri leaves grown in a plant factory with artificial lights. The immunomodulatory effects of A. hookeri leaves' ethanol extracts were evaluated with immune-related hematological factors in blood, the proliferation of splenocytes, NK cell activity, IgG and cytokine levels, and their mechanisms in immunosuppressed obese mice. Anti-diabetic effects were determined by the inhibitory activity against α-amylase and α-glucosidase in vitro and fasting blood glucose levels and biochemical factors in the serum of immunosuppressed obese mice. A. hookeri leaf extracts increased WBC and LYM counts, the proliferation of splenocytes, and serum IgG and IL-1β concentrations compared to those of the NC group, which was used as a negative control. A. hookeri leaf extracts also improved serum HDL levels while they decreased the activities of digestive enzymes, fasting blood glucose, and biochemical factors (ALT, AST, T-Chol, TG, LDL, and GLU). The expressions of IL-1β, JNK, c-Jun, p65, and iNOS in the thymus of immunosuppressed mice were activated by the treatment of A. hookeri leaf extracts. The results suggest that A. hookeri leaves grown in a plant factory with artificial lights also have immune-stimulatory and anti-diabetic effects and can be used as novel functional supplements to control related diseases and to improve public health.

Anisotropic microtopography surface of chitosan scaffold regulating skin precursor-derived Schwann cells towards repair phenotype promotes neural regeneration.

For repairing peripheral nerve and spinal cord defects, biomaterial scaffold-based cell-therapy was emerged as an effective strategy, requiring the positive response of seed cells to biomaterial substrate and environment signals. Previous work highlighted that the imposed surface properties of scaffold could provide important guidance cues to adhered cells for polarization. However, the insufficiency of native Schwann cells and unclear cellular response mechanisms remained to be addressed. Given that, this study aimed to illuminate the micropatterned chitosan-film action on the rat skin precursor-derived Schwann cells (SKP-SCs). Chitosan-film with different ridge/groove size was fabricated and applied for the SKP-SCs induction. Results indicated that SKP-SCs cultured on 30 μm size microgroove surface showed better oriented alignment phenotype. Induced SKP-SCs presented similar genic phenotype as repair Schwann cells, increasing expression of c-Jun, neural cell adhesion molecule, and neurotrophic receptor p75. Moreover, SKP-SC-secretome was subjected to cytokine array GS67 assay, data indicated the regulation of paracrine phenotype, a panel of cytokines was verified up-regulated at secreted level and gene expression level in induced SKP-SCs. These up-regulated cytokines exhibit a series of promotive neural regeneration functions, including cell survival, cell migration, cell proliferation, angiogenesis, axon growth, and cellular organization etc. through bioinformatics analysis. Furthermore, the effectively polarized SKP-SCs-sourced secretome, promoted the proliferation and migration capacity of the primarily cultured native rat Schwann cells, and augmented neurites growth of the cultured motoneurons, as well as boosted axonal regrowth of the axotomy-injured motoneurons. Taken together, SKP-SCs obtained pro-neuroregeneration phenotype in adaptive response to the anisotropic topography surface of chitosan-film, displayed the oriented parallel growth, the transition towards repair Schwann cell genic phenotype, and the enhanced paracrine effect on neural regeneration. This study provided novel insights into the potency of anisotropic microtopography surface to Schwann-like cells phenotype regulation, that facilitating to provide promising engineered cell-scaffold in neural injury therapies.

Pentadecanoic acid (C15:0, PA) induces mild maternal glucose intolerance and promotes the growth of the offspring partly through up-regulating liver PPARα and MAPK signaling pathways.

Gestational diabetes mellitus (GDM) is one of the most common metabolic disturbances during pregnancy, which poses a serious threat to both maternal and offspring health. Pentadecanoic acid (C15:0, PA) is one of the most common odd-chain saturated fatty acids (OCS-FAs). However, its safety and nutritional value are yet to be verified. Herein, we provide a systematic assessment of the effects of PA on maternal and progeny health and insulin sensitivity for the first time. Our results showed that consumption of 1% PA during pregnancy could increase the contents of PA and heptadecanoic acid (C17:0) in maternal plasma, fetal tissue and offspring plasma, but it had no effect on embryonic development. During pregnancy, PA treatment caused mild insulin resistance, while it had little effect on the maternal body composition. During lactation, PA treatment caused mild insulin resistance and oxidative stress. Maternal body fat deposition was also reduced, but the growth rate of the offspring was faster. It is worth noting that PA treatment decreased plasma and liver TG content and increased the antioxidant capacity of the offspring. The effect of PA on the transcription and expression genes in the liver of pregnant mice was investigated using RNA-seq. PPARα and MAPK signaling pathways, both closely related to lipolysis, inflammation, oxidative stress, and insulin resistance were significantly increased. The expression of c-JUN, ERK, JNK and P65 proteins was also significantly up-regulated. In conclusion, our results suggest that 1% PA can induce a mild decrease in the maternal glucose tolerance and lipolysis mainly by activated MAPK and PPARα signaling. Moreover, low concentrations of PA may be an effective nutrient to alleviate the oxidative stress and reduce blood lipid levels of offspring.

Identification and analysis of differently expressed transcription factors in aristolochic acid nephropathy.

Aristolochic acid nephropathy (AAN) is a rapidly progressive interstitial nephropathy caused by Aristolochic acid (AA). AAN is associated with the development of nephropathy and urothelial carcinoma. It is estimated that more than 100 million people worldwide are at risk of developing AAN. However, the underlying mechanisms driving renal deterioration in AAN remain poorly understood, and the treatment options are limited. We obtained GSE27168 and GSE136276 series matrix data from the Gene Expression Omnibus (GEO) related to AAN. Using the R Studio environment, we applied the limma package and WGCNA package to identify co-differently expressed genes (co-DEGs). By GO/KEGG/GSVA analysis, we revealed common biological pathways. Subsequently, co-DEGs were subjected to the String database to construct a protein-protein interaction (PPI) network. The MCC algorithms implemented in the Cytohubba plugin were employed to identify hub genes. The hub genes were cross-referenced with the transcription factor (TF) database to identify hub TFs. Immune infiltration analysis was performed to identify key immune cell groups by utilizing CIBERSORT. The expressions of AAN-associated hub TFs were verified in vivo and in vitro. Finally, siRNA intervention was performed on the two TFs to verify their regulatory effect in AAN. Our analysis identified 88 co-DEGs through the "limma" and "WGCNA" R packages. A PPI network comprising 53 nodes and 34 edges was constructed with a confidence level >0.4. ATF3 and c-JUN were identified as hub TFs potentially linked to AAN. Additionally, expressions of ATF3 and c-JUN positively correlated with monocytes, basophils, and vessels, and negatively correlated with eosinophils and endothelial cells. We observed a significant increase in protein and mRNA levels of these two hub TFs. Furthermore, it was found that siRNA intervention targeting ATF3, but not c-JUN, alleviated cell damage induced by AA. The knockdown of ATF3 protects against oxidative stress and inflammation in the AAN cell model. This study provides novel insights into the role of ATF3 in AAN. The comprehensive analysis sheds light on the molecular mechanisms and identifies potential biomarkers and drug targets for AAN treatment.

Galectin-1 Promotes Gastric Carcinoma Progression and Cisplatin Resistance Through the NRP-1/c-JUN/Wee1 Pathway.

Gastric cancer (GC) is among the deadliest malignancies and the third leading cause of cancer-related deaths worldwide. Galectin-1 (Gal-1) is a primary protein secreted by cancer-associated fibroblasts (CAFs); however, its role and mechanisms of action of Gal-1 in GC remain unclear. In this study, we stimulated GC cells with exogenous human recombinant galectin-1 protein (rhGal-1) to investigate its effects on the proliferation, migration, and resistance to cisplatin. We used simulated rhGal-1 protein as a paracrine factor produced by CAFs to induce GC cells and investigated its promotional effects and mechanisms in GC progression and cisplatin resistance. Immunohistochemical (IHC) assay confirmed that Gal-1 expression was associated with clinicopathological parameters and correlated with the expression of neuropilin-1 (NRP-1), c-JUN, and Wee1. Our study reveals Gal-1 expression was significantly associated with poor outcomes. Gal-1 boosts the proliferation and metastasis of GC cells by activating the NRP-1/C-JUN/Wee1 pathway. Gal-1 notably increases GC cell resistance to cisplatin The NRP-1 inhibitor, EG00229, effectively counteracts these effects. These findings revealed a potential mechanism by which Gal-1 promotes GC growth and contributes to chemoresistance, offering new therapeutic targets for the treatment of GC.

Interpreting the pharmacological mechanisms of Juanbi recipe on rheumatoid arthritis through network pharmacology, molecular docking.

Traditional Chinese medicine (TCM) offers the advantage of effectively relieving rheumatoid arthritis (RA) with minimal side effects. The Juanbi recipe is a commonly utilized TCM treatment for RA, yet its pharmacological mechanism remains unclear. Network pharmacology serves as an effective tool for identifying pharmaceutical ingredients and potential therapeutic targets of TCM, thereby uncovering its mechanisms. This study aimed to identify the core target genes and explore the mechanisms underlying the treatment of RA with the Juanbi recipe. This study adopted the method of network pharmacology to filter key gene targets of Juanbi recipe in RA treatment. Single-cell ribonucleic acid (RNA) sequencing data was used to screen the key genes to form the core genes of Juanbi recipe in RA treatment. The molecular docking technique was used to verify the core target genes and explore the mechanisms of Juanbi recipe in RA treatment. The RA model of mice was induced by the collagen-induced arthritis and the effect of Juanbi recipe was evaluated by intragastric administrating of extraction of Juanbi recipe. Enzyme linked immunosorbent assay was used to analysis serum inflammatory factors. Hematoxylin and eosin staining was used to evaluate inflammation and immunohistochemical (IHC) staining was used to evaluate core target genes and pathways in synovium of ankle. This study screened out 281 active molecules in Juanbi recipe, found 105 key target genes of Juanbi recipe in RA treatment, and drew an "ingredient - molecule - gene" diagram. Juanbi recipe reduced the levels of serum interleukin (IL)-1 and IL-6, the inflammatory infiltration in synovium, demonstration that Juanbi recipe reduced both systemic and synovial inflammatory response. Single cell RNA sequencing data were used to select six core target genes and six core active molecules of Juanbi recipe in RA treatment. The pathways of Juanbi recipe in RA treatment involved in activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB) pathway. Results of western blot and IHC staining showed that Juanbi recipe decreased the expressions of c-jun and p65, which demonstrated that Juanbi recipe inhibited the expression of AP-1 and NF-κB pathway in RA. The core active molecules of Juanbi recipe could inhibit key factors of AP-1 and NF-κB pathway to inhibit the inflammation, which played a protective role in RA.

Pro-inflammatory GPR75 and anti-apoptotic phospholipase signaling pathways contribute to the ameliorating effect of soluble epoxide hydrolase inhibition on chronic experimental autoimmune encephalomyelitis in mice.

Soluble epoxide hydrolase (sEH) inhibition has currently emerged as a therapeutic target in the treatment of various neuroinflammatory neurodegenerative diseases, including multiple sclerosis. Previously, we reported that treatment of mice with a sEH-selective inhibitor, 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl]urea; TPPU), ameliorated chronic experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein 35-55 peptide immunization followed by injection of pertussis toxin to mice via regulating pro-inflammatory and anti-inflammatory pathways in the central nervous system. This study tested the hypothesis that the pro-inflammatory G protein-coupled receptor (GPR) 75 and anti-apoptotic phospholipase C (PLC) signaling pathways also contribute to the ameliorating effect of TPPU on chronic EAE. Brains and spinal cords of phosphate-buffered saline-, dimethyl sulfoxide-, or TPPU (3 mg/kg)-treated mice were used for the measurement of sEH, GPR75, Gaq/11, activator protein (AP)-1, PLC β4, phosphoinositide 3-kinase (PI3K) p85a, Akt1, mitogen-activated protein kinase kinase (MEK) 1/2, extracellular signal-regulated kinase (ERK) 1/2, cyclic adenosine monophosphate-response element-binding protein (CREB) 1, B-cell lymphoma (Bcl)-2, semaphorin (SEMA) 3A, and myelin proteolipid protein (PLP) expression and/or activity by using the immunoblotting method. Expression of sEH, GPR75, Gaq/11, c-jun, phosphorylated c-Jun, and SEMA3A was lower, while PLCβ4, phosphorylated PI3K p85a, phosphorylated Akt1, phosphorylated MEK1/2, phosphorylated ERK1/2, phosphorylated CREB1, Bcl-2, and myelin PLP expression was higher in the tissues of TPPU (3 mg/kg)-treated mice as compared with the EAE and vehicle control groups. Inhibition of sEH by TPPU ameliorates chronic EAE through suppressing pro-inflammatory GPR75/Gaq/11/AP-1 pathway and reducing expression of the remyelination inhibitor, SEMA3A, as well as increasing anti-apoptotic PLC/PI3K/Akt1/MEK1/2/ERK1/2/CREB1/Bcl-2 pathway activity and myelin PLP expression.

Neurotrophin-3 promotes peripheral nerve regeneration by maintaining a repair state of Schwann cells after chronic denervation via the TrkC/ERK/c-Jun pathway

BackgroundMaintaining the repair phenotype of denervated Schwann cells in the injured distal nerve is crucial for promoting peripheral nerve regeneration. However, when chronically denervated, the capacity of Schwann cells to support repair and regeneration deteriorates, leading to peripheral nerve regeneration and poor functional recovery. Herein, we investigated whether neurotrophin-3 (NT-3) could sustain the reparative phenotype of Schwann cells and promote peripheral nerve regeneration after chronic denervation and aimed to uncover its potential molecular mechanisms.MethodsWestern blot was employed to investigate the relationship between the expression of c-Jun and the reparative phenotype of Schwann cells. The inducible expression of c-Jun by NT-3 was examined both in vitro and in vivo with western blot and immunofluorescence staining. A chronic denervation model was established to study the role of NT-3 in peripheral nerve regeneration. The number of regenerated distal axons, myelination of regenerated axons, reinnervation of neuromuscular junctions, and muscle fiber diameters of target muscles were used to evaluate peripheral nerve regeneration by immunofluorescence staining, transmission electron microscopy (TEM), and hematoxylin and eosin (H&E) staining. Adeno-associated virus (AAV) 2/9 carrying shRNA, small molecule inhibitors, and siRNA were employed to investigate whether NT-3 could signal through the TrkC/ERK pathway to maintain c-Jun expression and promote peripheral nerve regeneration after chronic denervation.ResultsAfter peripheral nerve injury, c-Jun expression progressively increased until week 5 and then began to decrease in the distal nerve following denervation. NT-3 upregulated the expression of c-Jun in denervated Schwann cells, both in vitro and in vivo. NT-3 promoted peripheral nerve regeneration after chronic denervation, mainly by upregulating or maintaining a high level of c-Jun rather than NT-3 itself. The TrkC receptor was consistently presented on denervated Schwann cells and served as NT-3 receptors following chronic denervation. NT-3 mainly upregulated c-Jun through the TrkC/ERK pathway.ConclusionNT-3 promotes peripheral nerve regeneration by maintaining the repair phenotype of Schwann cells after chronic denervation via the TrkC/ERK/c-Jun pathway. It provides a potential target for the clinical treatment of peripheral nerve injury after chronic denervation.

FRI109 D-Allulose Inhibits NF-kB- And AP1-Mediated Inflammatory Pathways In HepG2 Cells

Abstract Disclosure: N. Gupta: None. J. Batch-Joudi: None. L.D. Graham: None. K. Champagne: None. F. Warda: None. M.J. Haas: None. A. Mooridian: None. Nothing to Disclose: NG, J B-J, LG, KC, FW, MJH, ADM. Source of Research Support: No outside funding was used for this research. Rare sugars such as D-allulose and its derivatives are defined as monosaccharides that are rare in nature. D-allulose is an epimer of D-fructose and is used primarily as a non-nutritive sweetener. D-allulose is also a functional food due to its ability to lower fasting plasma glucose and post-prandial glucose levels in both normoglycemic and diabetics, most likely due to its insulin-mimetic properties as well as its ability to enhance glucagon-like peptide 1. D-alluose has also been shown to possess anti-inflammatory and immunosuppressant activity in allogenic orthotopic liver transportation, neutrophil activation, and monocyte chemoattractant protein-1 expression in endothelial cells. We examined the effects of D-allulose on two well characterized pathways that promote inflammation in HepG2 hepatoblastoma cells, specifically nuclear factor κB (NF-κB) and activator protein 1 (AP1). HepG2 cells were exposed to tumor necrosis factor α (TNFα) (10 ng/ml), lipopolysaccharide (LPS) (10 nM), and high dextrose (27.5 mM). Treatment with 0, 2.8, 5.5, 11, 22, and 27.5 mM D-allulose decreased TNFα-dependent NF-κB and AP1 reporter plasmid activity and 2.8- and 5.5-mM D-alluose decreased NF-κB p50 and p65 subunit expression, measured by Western blot. D-allulose treatment increased IκB expression in TNFα treated cells. D-alluose also suppressed c-jun, phospho-c-jun, and c-fos AP1 subunit expression in TNFα treated cells. Similar effects were observed in D-allulose-treated cells (2.8 and 5.5 mM) exposed to high dextrose and LPS. These results suggest that D-allulose mediates some of its anti-inflammatory effects via suppressing NF-κB and AP1 activity. Presentation: Friday, June 16, 2023

PRRSV alters m6A methylation and alternative splicing to regulate immune, extracellular matrix-associated function

The alternative splicing and N6-methyladenosine (m6A) modifications occurring during porcine reproductive and respiratory syndrome virus (PRRSV) infections remain poorly understood. Transcriptome and MeRIP-seq analyses were performed to identify the gene expression changes, splicing and m6A modifications in the lungs of PRRSV-infected pigs. In total, 1624 differentially expressed genes (DEGs) were observed between PRRSV-infected and uninfected pigs. We observed significant alterations in alternative splicing (54,367 events) and m6A modifications (2265 DASEs) in numerous genes, including LMO7, SLC25A27, ZNF185, and ECM1, during PRRSV infection. LMO7 and ZNF185 exhibited alternative splicing variants and reduced mRNA expression levels following PRRSV infection. Notably, LMO7 inhibited c-JUN, SMAD3, and FAK expression, whereas ZNF185 affected the expression of FAK, CDH1, and GSK3β downstream. Additionally, ECM1 influenced FAK expression by targeting ITGB3 and AKT2, suggesting its involvement in extracellular matrix accumulation through the ITGB3-AKT2/FAK pathway. These changes may facilitate viral invasion and replication by modulating the expression of genes and proteins participating in crucial cellular processes associated with immunity and the extracellular matrix. We highlight the importance of these genes and their associated pathways in PRRSV infections and suggest that targeting these may be a promising therapeutic approach for treating viral infections.

Selenium-Chitosan Protects Porcine Endometrial Epithelial Cells from Zearalenone-induced Apoptosis via the JNK/SAPK Signaling Pathway.

This study was designed to assess whether selenium-chitosan (Se-CTS) can protect porcine endometrial epithelial cells (PEECs) against damage and apoptosis induced by zearalenone (ZEA) via modulating the JNK/SAPK signaling pathway. The cell cycle, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and apoptosis rates of porcine endometrial epithelial cells were determined, as well as the expression levels of genes related to the SAPK/JNK signaling pathway. The results showed that 3.0µmol/L Se-CTS decreased the percentage of ZEA-induced G1 phase in PEECs (P < 0.01), whereas 1.5 and 3.0µmol/L Se-CTS increased the percentage of ZEA-induced percentage of G2 phase of PEECs (P < 0.01). Further, Se-CTS at 1.5 and 3.0µmol/L improved the ZEA-induced decrease in MMP (P < 0.01), whereas Se-CTS at 0.5, 1.5, and 3.0µmol/L reduced the increase in ROS levels and apoptosis rate induced by ZEA in PEECs (P < 0.01 or P < 0.05). Furthermore, 3.0µmol/L Se-CTS ameliorated the increase in the expression of c-Jun N-terminal kinase (JNK), apoptosis signal-regulated kinase (ASK1), and c-Jun induced by ZEA (P < 0.01) and the reduction in mitogen-activated protein kinase kinase 4 (MKK4) and protein 53 (p53) expression (P < 0.01), while 1.5µmol/L Se-CTS improved the expression of ASK1 and c-Jun induced by ZEA (P < 0.05). The results proved that Se-CTS alleviates ZEA-induced cell cycle stagnation, cell mitochondrial damage, and cell apoptosis via decreasing ZEA-produced ROS and modulating the JNK/SAPK signaling pathway.

Topical metformin accelerates wound healing by promoting collagen synthesis and inhibiting apoptosis in a diabetic wound model.

The wound healing process, which is a pathophysiological process that includes various phases, is interrupted in diabetes due to hyperglycemia, and since deterioration occurs in these phases, a normal healing process is not observed. The aim of the current study is to investigate the proliferative and antiapoptotic effects of metformin on wound healing after topical application on diabetic and non-diabetic wounds. For this purpose, we applied metformin topically on the full-thickness excisional wound model we created in diabetic and nondiabetic groups. We investigated the effects of metformin on the apoptotic index by the Terminal deoxynucleotidyl transferase mediated dUTP Nick-End Labeling method and on collagen-I, collagen-III, p53, and c-jun expression levels by quantitative reverse transcription polymerase chain reaction technique in wound biopsy tissues. Our results showed that c-jun and p53 mRNA levels and apoptotic index increased with the effect of diabetes, while collagen synthesis was disrupted. As a result of the study, we showed that metformin increases cellular proliferation and has anti-apoptotic effects by increasing collagen-I/III expression and decreasing p53/c-jun level, especially in diabetic wounds and also in normal wounds. In conclusion, the topical effect of metformin on diabetic wounds reversed the adverse effects caused by diabetes, increasing the wound healing rate and improving the wound repair process.

Schwann Cells Reprogram Into Repair Phenotype Instead of Dedifferentiating to Immature Phenotype in in Vitro Culture

Introduction: In vitro cultured Schwann cell has been suggested to adopt a phenotype of undifferentiated immature Schwann cells found in vivo during development. However, recent studies indicate that Schwann cells undergo cellular reprogramming into the phenotype of repair Schwann cells instead of reverting to an immature phenotype after peripheral nerve injury. The study hypothesized that in in vitro culture, Schwann cells assume the repair phenotype instead of de-differentiating to immature Schwann cells, similar to in vivo nerve injury response. Therefore, this study aimed to characterize the phenotype of cultured Schwann cells by examining the expression of classic Schwann markers and transcription factors c-Jun and Krox-20. Methods: Schwann cells, isolated from Wistar rat sciatic nerve, were grown in a standard Schwann cell growth medium for seven days. Then, cultured Schwann cells were analyzed using immunofluorescence analysis for classic Schwann cell markers (neurotrophin receptor p75 (p75NTR) and myelin basic protein (MBP)) and the expression profile of transcription factor c-Jun and Krox-20. Results: Immunofluorescence analysis revealed that cultured Schwann cells expressed a significantly high level of repair phenotype biomarkers (p75NTR and c-Jun) compared to the level of myelinating phenotype biomarkers (MBP and Krox-20). Conclusion: Schwann cells reprogram into repair Schwann cells instead of de-differentiating to immature Schwann cells in vitro.

Analysis of the Promoter Regions of gga-miR-31 and Its Regulation by RA and C-jun in Chicken.

The role of gga-miR-31 in chicken germ cell differentiation and spermatogenesis is of significant importance. The transcriptional properties of gga-miR-31 are crucial in establishing the foundation for the formation of chicken spermatogonia stem cells and spermatogenesis. In this study, a series of recombinant vectors including varying lengths of the gga-miR-31 promoter were predicted and constructed. Through the utilization of the dual luciferase reporting system, the upstream -2180~0 bp region of gga-miR-31 was identified as its promoter region. Furthermore, it was predicted and confirmed that the activity of the gga-miR-31 promoter is increased by retinoic acid (RA). The binding of RA to the gga-miR-31 and Stra8 promoter regions was found to be competitive. Through the deletion of C-jun binding sites and the manipulation of C-jun expression levels, it was determined that C-jun inhibits the activity of the gga-miR-31 promoter. Furthermore, the combined treatment of C-jun and RA demonstrated that the positive regulatory effect of RA on the gga-miR-31 promoter is attenuated in the presence of high levels of C-jun. Overall, this study establishes a foundation for further investigation into the regulatory mechanisms of gga-miR-31 action, and provides a new avenue for inducing chicken embryonic stem cells (ESC) to differentiate into spermatogonial stem cells (SSC), and sperm formation.

Physical interaction between STAT3 and AP1 in cervical carcinogenesis: Implications in HPV transcription control

The constitutive activation and aberrant expression of Signal Transducer and Activator of Transcription 3 (STAT3) plays a key role in initiation and progression of cervical cancer (CaCx). How STAT3 influences HPV transcription is poorly defined. In the present study, we probed direct and indirect interactions of STAT3 with HPV16/18 LCR. In silico assessment of cis-elements present on LCR revealed the presence of potential STAT3 binding motifs. However, experimental validation by ChIP-PCR could not confirm any specific STAT3 binding on HPV16 LCR. Protein-protein interaction (PPI) network analysis of STAT3 with other host transcription factors that bind LCR, highlighted the physical association of STAT3 with c-FOS and c-JUN. This was further confirmed in vitro by co-immunoprecipitation, where STAT3 co-immunoprecipitated with c-FOS and c-JUN in CaCx cells. The result was supported by immunocytochemical analysis and colocalization of STAT3 with c-FOS and c-JUN. Positive signals in proximity ligation assay validated physical interaction and colocalization of STAT3 with AP1. Colocalization of STAT3 with c-FOS and c-JUN increased upon IL-6 treatment and decreased post-Stattic treatment. Alteration of STAT3 expression affected the subcellular localization of c-FOS and c-JUN, along with the expression of viral oncoproteins (E6 and E7) in CaCx cells. High expression of c-JUN in tumor tissues correlated with poor prognosis in both HPV16 and HPV18 CaCx cohort whereas high expression of STAT3 correlated with poor prognosis in HPV18 CaCx lesions only. Overall, the data suggest an indirect interaction of STAT3 with HPV LCR via c-FOS and c-JUN and potentiate transcription of viral oncoproteins.