Thioredoxin and thioredoxin-interacting protein as prognostic markers for gastric cancer recurrence

AIM:To evaluate the potential of thioredoxin (TXN) and thioredoxin-interacting protein (TXNIP) expression as biomarkers for predicting gastric cancer recurrence. METHODS:TXN and TXNIP expression levels were acquired from gene expression microarray data for 65 human gastric cancer tissues. We determined whether each gene expression level was associated with cancer recurrence and investigated the relationship between the two genes. For validation, the expression levels of TXN and TXNIP were measured by quantitative real- time reverse transcription polymerase chain reaction in 68 independent stage Ⅲ gastric cancer patients. The correlation between gene expression and cancer prognosis was evaluated. Immunohistochemical staining was performed to investigate the protein expression levels of TXN and TXNIP and to characterize the expression patterns of each protein. RESULTS:TXN was a prognosis-related gene (P = 0.009), whereas TXNIP, a TXN inhibitor, demonstrated a negative correlation with TXN in the gene expression microarray data. In the 68 stage Ⅲ patients, the expression levels of both TXN and TXNIP had a statistically significant effect on recurrence-free survival (RFS, P = 0.008 and P = 0.036, respectively). The low TXN and high TXNIP expression group exhibited a better prognosis than the other groups, and the high TXN and low TXNIP expression group exhibited a poorer prognosis (P < 0.001 for RFS and P = 0.001 for overall survival). More than half of the patients in the simulta-neously high TXN and low TXNIP expression group ex- perienced a recurrence within 1 year after curative surgery, and the 5-year survival rate of the patients in this group was 29%, compared with 89% in the low TXN and high TXNIP expression group. The TXN protein was overexpressed in 65% of the gastric cancer tissues, whereas the TXNIP protein was underexpressed in 85% of the cancer cells. In a correlation analysis, TXN and TXNIP were highly correlated with many oncogenes and tumor suppressors as well as with genes related to energy, protein synthesis and autophagy. CONCLUSION:TXN and TXNIP are promising prognostic markers for gastric cancer, and performing personalized adjuvant treatment based on TXN and TXNIP expression levels would be an effective practice in the treatment of gastric cancer.

Effect of thioredoxin-interacting protein on Wnt/β-catenin signaling pathway and diabetic myocardial infarction

Objective:To explore the regulatory role of thioredoxin-interacting protein(TXNIP) in Wnt/β-catenin signaling pathway and therefore to elucidate its function in diabetic myocardial infarction.Methods:Diabetic myocardial infarction models were generated in mice.The expression levels of TXNIP and β-catenin and level of reactive oxygen species(ROS) were determined and compared with those in control group.Human umbilical vein endothelial cells were treated with high-eoncentration glucose and/or silencing TXNIP and/or H_2O_2.After 24 h,expression levels of TXNIP、β-catenin and its downstream protein Cyclin D1,and C-myc gene were determined by real-time PCR,Western blot and immunofluorescence method.The cell proliferation and ROS production capability in different groups were determined by methyl thiazolyl tetrazolium assay.Results:Compared with control group,hyperglycemia significantly up-regulated TXNIP expression and ROS level in the myocardium and endothelial cells of myocardial infarction area,whereas the β-catenin expression was down-regulated,and the difference was statistically significant(P<0.05).In comparison with Human umbilical vein endothelial cells in the control group,high glucose level increased the levels of TXNIP expression and ROS level in cells,but reduced cell proliferation as well as migration capability and expression levels of β-catenin,Cyclin D1 and C-myc;the difference was statistically significant(P<0.05).However,this trend can be partially reversed by silencing TXNIP.Conclusions:Diabetic myocardial ischemia could up-regulate levels of TXNIP expression and ROS production in endothelial cells of myocardial infarction area.The regulation effect of TXNIP on β-catenin was partially achieved by changing ROS levels.

AstragalosideⅣplays a role in reducing radiation-induced liver inflammation in mice by inhibiting thioredoxin-interacting protein/nod-like receptor protein 3 signaling pathway

OBJECTIVE:To investigate the efficacy of Astragaloside IV(AS-IV)on radiation-induced liver inflammation in mice.METHODS:The mice were divided into normal group,dimethyl sulfoxide solvent group,irradiation group(IR),irradiation+AS-IV(20 mg/kg)group(IR+AS-20)and irradiation+AS-IV(40 mg/kg)group(IR+AS-40).One month after intraperitoneal injection of AS-IV,the mice were irradiated with 8Gry Co60γ,the blood was collected for biochemical analysis,and the liver was collected for hematoxylin-eosin staining,immunofluorescence and electron microscopic observation,oxidative stress,and Western blot analysis.RESULTS:The AS-IV treatment significantly ameliorated the pathological morphology of liver and reduced the alanine aminotransferase and aspertate aminotransferase levels in serum induced by radiation;AS-IV treatment also significantly reduced the expression of inflammatory factors tumor necrosis factor alpha and interleukin 6 and antagonized malonaldehyde content and superoxide dismutase activity in liver caused by radiation;in addition,AS-IV treatment can significantly inhibited the positive expression of thioredoxin-interacting protein(TXNIP)and nod-like receptor protein 3(NLRP3)inflammasome in liver tissue after radiation;The expression of TXNIP,NLRP3 inflammasome,apoptosisassociated speck-like protein containing a CARD,cysteinyl aspartate-specific proteinase 1 and interleukin 1beta in the AS-IV prevention group decreased significantly compared to the radiation group.CONCLUSIONS:These findings suggested that Co60γradiation can cause structural and functional damage to the liver,which may be related to the NLRP3 mediated inflammatory pathway;AS-IV may play a protective role by inhibiting the TXNIP/NLRP3 inflammasome signaling pathway in the radiation-induced liver injury model.

High fat diet dysregulates microRNA-17-5p and triggers retinal inflammation:Role of endoplasmic-reticulum-stress

AIM To elucidate how high diet-induced endoplasmic reticulum-stress upregulates thioredoxin interacting protein expression in Müller cells leading to retinal inflammation. METHODS Male C57Bl/J mice were fed either normal diet or 60% high fat diet for 4-8 wk. During the 4 wk study, mice received phenyl-butyric acid(PBA); endoplasmic reticulum-stress inhibitor; for 2 wk. Insulin resistance was assessed by oral glucose tolerance. Effects of palmitate-bovine serum albumin(BSA)(400 μmol/L) were examined in retinal Müller glial cell line and primary Müller cells isolated from wild type and thioredoxin interacting protein knock-out mice. Expression of thioredoxin interacting protein, endoplasmic reticulum-stress markers, mi R-17-5p m RNA, as well as nucleotide-binding oligomerization domain-like receptor protein(NLRP3) and IL1β protein was determined.RESULTS High fat diet for 8 wk induced obesity and insulin resistance evident by increases in body weight and impaired glucose tolerance. By performing quantitative real-time polymerase chain reaction, we found that high fat diet triggered the expression of retinal endoplasmic reticulum-stress markers(P < 0.05). These effects were associated with increased thioredoxin interacting protein and decreased mi R-17-5p expression, whichwere restored by inhibiting endoplasmic reticulumstress with PBA(P < 0.05). In vitro, palmitate-BSA triggered endoplasmic reticulum-stress markers, which was accompanied with reduced mi R-17-5p and induced thioredoxin interacting protein m RNA in retinal Müller glial cell line(P < 0.05). Palmitate upregulated NLRP3 and IL1β expression in primary Müller cells isolated from wild type. However, using primary Müller cells isolated from thioredoxin interacting protein knock-out mice abolished palmitate-mediated increase in NLRP3 and IL1β.CONCLUSION Our work suggests that targeting endoplasmic reticulumstress or thioredoxin interacting protein are potential therapeutic strategies for early intervention of obesityinduced retinal inflammation.

Extracellular vesicles from hypoxia-preconditioned mesenchymal stem cells alleviates myocardial injury by targeting thioredoxininteracting protein-mediated hypoxia-inducible factor-1αpathway

BACKGROUND Extracellular vesicles(EVs)derived from hypoxia-preconditioned(HP)mesenchymal stem cells(MSCs)have better cardioprotective effects against myocardial infarction(MI)in the early stage than EVs isolated from normoxic(NC)-MSCs.However,the cardioprotective mechanisms of HP-EVs are not fully understood.AIM To explore the cardioprotective mechanism of EVs derived from HP MSCs.METHODS We evaluated the cardioprotective effects of HP-EVs or NC-EVs from mouse adipose-derived MSCs(ADSCs)following hypoxia in vitro or MI in vivo,in order to improve the survival of cardiomyocytes(CMs)and restore cardiac function.The degree of CM apoptosis in each group was assessed by the terminal deoxynucleotidyl transferase dUTP nick end-labeling and Annexin V/PI assays.MicroRNA(miRNA)sequencing was used to investigate the functional RNA diversity between HP-EVs and NC-EVs from mouse ADSCs.The molecular mechanism of EVs in mediating thioredoxin-interacting protein(TXNIP)was verified by the dual-luciferase reporter assay.Co-immunoprecipitation,western blotting,and immunofluorescence were performed to determine if TXNIP is involved in hypoxia-inducible factor-1 alpha(HIF-1α)ubiquitination and degradation via the chromosomal region maintenance-1(CRM-1)-dependent nuclear transport pathway.RESULTS HP-EVs derived from MSCs reduced both infarct size(necrosis area)and apoptotic degree to a greater extent than NC-EVs from CMs subjected to hypoxia in vitro and mice with MI in vivo.Sequencing of EV-associated miRNAs showed the upregulation of 10 miRNAs predicted to bind TXNIP,an oxidative stress-associated protein.We showed miRNA224-5p,the most upregulated miRNA in HP-EVs,directly combined the 3’untranslated region of TXNIP and demonstrated its critical protective role against hypoxia-mediated CM injury.Our results demonstrated that MI triggered TXNIP-mediated HIF-1αubiquitination and degradation in the CRM-1-mediated nuclear transport pathway in CMs,which led to aggravated injury and hypoxia tolerance in CMs in the early stage of MI.CONCLUSION The anti-apoptotic effects of HP-EVs in alleviating MI and the hypoxic conditions of CMs until reperfusion therapy may partly result from EV miR-224-5p targeting TXNIP.

Myrrh extract alleviated ROS-mediated ferroptosis through regulating TXNIP/NLRP3 axis in ischemic stroke

OBJECTIVE To investigate the neuroprotective effects and exact mechanisms of myrrh extract following cerebral ischemic stroke.METHODS Male rats were randomly divided into three groups:sham group,middle cerebral artery occlusion(MCAO)group and myrrh group.Morphological changes were assessed after 7 d of myrrh treatment.Microarray analysis with circulating mRNA was performed to identify differential gene expression profile,gene ontology and pathway enrichment analyses were carried out to predict the gene function.Gene co-expression and pathway networks were constructed to identify the potential targets.The markers of oxidative stress,inflammatory reaction and ferroptosis in the cerebral cortex were detected by ELISA assays.The identified hub pathways and genes were validated by western blotting,immunofluorescence and immunohistochemistry analyses.Neurons were exposed to transient oxygen-glucose deprivation(OGD)to model ischemia-like conditions.siRNA-TXNIP were transfected in OGD-induced neurons to explore the mechanism.RESULTS Myrrh extract significantly alleviated neurological deficits,infarct volume and histo⁃pathological damage in MCAO rats.A total of 2200 differentially expressed genes were identified among the three groups.Oxidation-reduction process,inflammatory response,ferroptosis were enriched as the significant gene ontology items.NOD-like receptor signaling were identified as the hub pathway based on the pathway relation network.TXNIP and NLRP3 were screened as the potential targets by a time sequence profile analysis.The levels of IL-1β,IL-18,TNF-α,MDA and TFR in brain tissues were increased while the CAT,SOD,GSH-px and GPX4 levels were significantly decreased in MCAO group.As expected,myrrh extract greatly reversed these changes.The similarly results were also observed in OGD treated neuron cells.The elevated expressions of TXNIP and NLRP3 induced by OGD were success⁃fully inhibited by myrrh treatment.Knockdown of TXNIP significantly alleviated OGD-induced ROS accumulation and oxidative stress,but the antioxidative effect of myrrh was impaired when TXNIP was absent in neuron cells.In addition,knockdown of TXNIP significantly decreased the expression of NLRP3 and increased the expression of GPX4 in OGDinduced neuron cells.However,myrrh treatment scarcely changed the expressions of NLRP3 and these ferroptosis markers in siRNA-TXNIP pretreated cells,compared with the siRNA-TXNIP alone treatment group.Therefore,these data demonstrated that the neuroprotective effect of myrrh extract was dependent on TXNIP-NLRP3 axis.CONCLU⁃SION Thatmyrrh extract exerts neuroprotective property through alleviated ROS-mediated ferroptosis by regulating the TXNIP/NLRP3 axis in ischemic stroke.Myrrh extract could be considered as a promising candidate for the treatment of ischemic stroke.

Gamma-aminobutyric acid enhances miR-21-5p loading into adipose-derived stem cell extracellular vesicles to alleviate myocardial ischemia-reperfusion injury via TXNIP regulation

BACKGROUND Myocardial ischemia-reperfusion injury(MIRI)poses a prevalent challenge in current reperfusion therapies,with an absence of efficacious interventions to address the underlying causes.AIM To investigate whether the extracellular vesicles(EVs)secreted by adipose mesenchymal stem cells(ADSCs)derived from subcutaneous inguinal adipose tissue(IAT)underγ-aminobutyric acid(GABA)induction(GABA-EVs^(IAT))demonstrate a more pronounced inhibitory effect on mitochondrial oxidative stress and elucidate the underlying mechanisms.METHODS We investigated the potential protective effects of EVs derived from mouse ADSCs pretreated with GABA.We assessed cardiomyocyte injury using terminal deoxynucleotidyl transferase dUTP nick end-labeling and Annexin V/propidium iodide assays.The integrity of cardiomyocyte mitochondria morphology was assessed using electron microscopy across various intervention backgrounds.To explore the functional RNA diversity between EVs^(IAT)and GABA-EVs^(IAT),we employed microRNA(miR)sequencing.Through a dual-luciferase reporter assay,we confirmed the molecular mechanism by which EVs mediate thioredoxin-interacting protein(TXNIP).Western blotting and immunofluorescence were conducted to determine how TXNIP is involved in mediation of oxidative stress and mitochondrial dysfunction.RESULTS Our study demonstrates that,under the influence of GABA,ADSCs exhibit an increased capacity to encapsulate a higher abundance of miR-21-5p within EVs.Consequently,this leads to a more pronounced inhibitory effect on mitochondrial oxidative stress compared to EVs from ADSCs without GABA intervention,ultimately resulting in myocardial protection.On a molecular mechanism level,EVs regulate the expression of TXNIP and mitigating excessive oxidative stress in mitochondria during MIRI process to rescue cardiomyocytes.CONCLUSION Administration of GABA leads to the specific loading of miR-21-5p into EVs by ADSCs,thereby regulating the expression of TXNIP.The EVs derived from ADSCs treated with GABA effectively ameliorates mitochondrial oxidative stress and mitigates cardiomyocytes damage in the pathological process of MIRI.