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1.
J Biomed Sci ; 29(1): 63, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36050716

RESUMO

Fibrosis-related disorders account for an enormous burden of disease-associated morbidity and mortality worldwide. Fibrosis is defined by excessive extracellular matrix deposition at fibrotic foci in the organ tissue following injury, resulting in abnormal architecture, impaired function and ultimately, organ failure. To date, there lacks effective pharmacological therapy to target fibrosis per se, highlighting the urgent need to identify novel drug targets against organ fibrosis. Recently, we have discovered the critical role of a fibroblasts-enriched endoplasmic reticulum protein disulfide isomerase (PDI), thioredoxin domain containing 5 (TXNDC5), in cardiac, pulmonary, renal and liver fibrosis, showing TXNDC5 is required for the activation of fibrogenic transforming growth factor-ß signaling cascades depending on its catalytic activity as a PDI. Moreover, deletion of TXNDC5 in fibroblasts ameliorates organ fibrosis and preserves organ function by inhibiting myofibroblasts activation, proliferation and extracellular matrix production. In this review, we detailed the molecular and cellular mechanisms by which TXNDC5 promotes fibrogenesis in various tissue types and summarized potential therapeutic strategies targeting TXNDC5 to treat organ fibrosis.


Assuntos
Isomerases de Dissulfetos de Proteínas , Tiorredoxinas , Fibroblastos/metabolismo , Fibrose , Humanos , Miofibroblastos , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(7): 689-692, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36100404

RESUMO

OBJECTIVE: To investigate the inhibitory effect and mechanism of heme oxygenase-1 (HO-1) on the inflammatory response of macrophages. METHODS: Mouse macrophage strain RAW264.7 was cultured in vitro, and the cells in the logarithmic growth phase were used for the experiment. The RAW264.7 cells were divided into four groups. In blank control group, the cells were continuously incubated and received no treatment (cultured at 37 centigrade, 95% air, 5% CO2). In lipopolysaccharide (LPS) model group, 1 mg/L LPS was added to the medium to prepare LPS challenge model. In HO-1 inducer group, the cells were incubated with 30 µmol/L HO-1 inducer hemin for 1 hour, and then 1 mg/L LPS was added for incubation. In HO-1 inhibition group, the cells were incubated with 5 µmol/L HO-1 specific antagonist Zinc protoporphyrin IX (ZnPPIX) for 0.5 hour, and then 1 mg/L LPS was added for incubation. After 48 hours of incubation with LPS, the supernatant of each group was taken, and the protein expressions of HO-1, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), thioredoxin interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3) and mitochondrial autophagy marker microtubule-associated protein 1 light chain 3B (LC-3B) were detected by Western blotting. The expression of reactive oxygen species (ROS) was detected by immunofluorescence staining. RESULTS: Compared with the blank control group, the cells in the LPS model group had a certain stress response, and autophagy occurred in mitochondria, but the expression of some inflammatory factors was restricted, which was related to the impairment of cell function. The protein expressions of HO-1, IL-1ß, LC-3B, ROS were significantly increased, the protein expressions of TNF-α, TXNIP, and NLRP3 were decreased significantly, indicating that the cells were seriously injured after LPS challenge, and the model was successfully established. Compared with the LPS model group, HO-1 protein expression in the HO-1 inducer group was significantly increased (HO-1/GAPDH: 0.31±0.03 vs. 0.22±0.03, P < 0.05), the protein expressions of TNF-α, IL-1ß, TXNIP, NLRP3, LC-3B and ROS were significantly inhibited [TNF-α protein (TNF-α/GAPDH): 0.08±0.01 vs. 0.45±0.05, IL-1ß protein (IL-1ß/GAPDH): 0.50±0.01 vs. 0.82±0.03, TXNIP protein (TXNIP/GAPDH): 0.21±0.02 vs. 0.28±0.02, NLRP3 protein (NLRP3/GAPDH): 0.11±0.01 vs. 0.17±0.02, LC-3B protein (LC-3B/GAPDH): 0.67±0.04 vs. 0.92±0.12, ROS (fluorescence intensity): 80.9±12.5 vs. 94.1±19.5, all P < 0.05], indicating that HO-1 could inhibit inflammatory response and oxidative stress, and reduce mitochondrial autophagy. Antagonizing HO-1 could increase inflammatory response, oxidative stress and mitochondrial autophagy, the inhibitory degree of TNF-α and IL-1ß expression was significantly reduced as compared with the HO-1 inducer group [TNF-α protein (TNF-α/GAPDH): 0.26±0.02 vs. 0.08±0.01, IL-1ß protein (IL-1ß/GAPDH): 0.76±0.01 vs. 0.50±0.01, both P < 0.05], the protein expressions of TXNIP, NLRP3, LC-3B and ROS were significantly increased as compared with the LPS model group [TXNIP protein (TXNIP/GAPDH): 0.43±0.02 vs. 0.28±0.02, NLRP3 protein (NLRP3/GAPDH): 0.24±0.02 vs. 0.17±0.02, LC-3B protein (LC-3B/GAPDH): 1.12±0.07 vs. 0.92±0.12, ROS (fluorescence intensity): 112.0±17.0 vs. 94.1±19.5, all P < 0.05]. CONCLUSIONS: HO-1 can reduce the inflammatory response by inhibiting the activation of TXNIP/NLRP3 inflammasome and reducing the release of inflammatory mediators.


Assuntos
Heme Oxigenase-1 , Inflamassomos , Animais , Heme Oxigenase-1/metabolismo , Inflamassomos/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
Oxid Med Cell Longev ; 2022: 4674215, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111165

RESUMO

Lipotoxicity can lead to beta-cell dysfunction and apoptosis because it induces oxidative stress. Recent studies have found that Irisin prevents pancreatic beta-cell dysfunction induced by palmitic acid (PA). However, an association between the protection against oxidative stress conferred by Irisin and beta-cell dysfunction has not been fully elucidated. In this study, we observed that Irisin treatment prevented INS-1 cell apoptosis induced by PA treatment and preserved the insulin-secreting function of INS-1 cells in vitro. These effects probably resulted from the Irisin-induced decrease in intracellular ROS levels triggered by PA treatment. In addition, PA treatment induced oxidative stress partially by inhibiting the activation of thioredoxin 2 (Trx2) through its increase of thioredoxin-interacting protein (Txnip) expression. However, Irisin administration blocked the increase in Txnip expression, which reversed the PA-induced inactivation of Trx2. Irisin also increased the nuclear translocation of Stat3, and the inhibition of Stat3 by siRNAs blocked Irisin-induced Trx2 expression, indicating that both Txnip and Stat3 are involved in Irisin-induced activation of Trx2. Furthermore, blockade of Stat3 by siRNAs led to the decreased gene expression of MafA and Ins and to cessation of glucose-induced insulin secretion that had been enhanced by Irisin. In vivo, HFD treatment led to reduced glucose tolerance and an increase in the level of the oxidative marker malondialdehyde (MDA) compared to that in the control group. However, these effects were ameliorated by Irisin injection due to the inhibition of beta-cell apoptosis and the activation of Trx2, probably through Txnip inhibition and Stat3 activation. In conclusion, our results reveal a possible mechanism for Irisin-induced beta-cell protection, which is mediated through Txnip inhibition and activation of the Stat3-Trx2 pathway.


Assuntos
Fibronectinas , Tiorredoxinas , Fibronectinas/metabolismo , Glucose/toxicidade , Insulina/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Ácido Palmítico/toxicidade , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Tiorredoxinas/metabolismo
4.
Front Immunol ; 13: 955128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059548

RESUMO

Target identification is essential for developing novel therapeutic strategies in diseases. Thioredoxin-interacting protein (TXNIP), also known as thioredoxin-binding protein-2, is a member of the α-arrestin protein family and is regulated by several cellular stress factors. TXNIP overexpression coupled with thioredoxin inhibits its antioxidant functions, thereby increasing oxidative stress. TXNIP is directly involved in inflammatory activation by interacting with Nod-like receptor protein 3 inflammasome. Bone metabolic disorders are associated with aging, oxidative stress, and inflammation. They are characterized by an imbalance between bone formation involving osteoblasts and bone resorption by osteoclasts, and by chondrocyte destruction. The role of TXNIP in bone metabolic diseases has been extensively investigated. Here, we discuss the roles of TXNIP in the regulatory mechanisms of transcription and protein levels and summarize its involvement in bone metabolic disorders such as osteoporosis, osteoarthritis, and rheumatoid arthritis. TXNIP is expressed in osteoblasts, osteoclasts, and chondrocytes and affects the differentiation and functioning of skeletal cells through both redox-dependent and -independent regulatory mechanisms. Therefore, TXNIP is a potential regulatory and functional factor in bone metabolism and a possible new target for the treatment of bone metabolism-related diseases.


Assuntos
Doenças Ósseas Metabólicas , Tiorredoxinas , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/metabolismo , Proteínas de Transporte/metabolismo , Humanos , Inflamassomos/metabolismo , Doenças Metabólicas/genética , Doenças Metabólicas/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
5.
Oxid Med Cell Longev ; 2022: 1497813, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35993020

RESUMO

Aim: Chronic inflammation is crucial for age-related macular degeneration (AMD) pathogenesis. However, the mechanism involved in activating inflammation remains unclear. This study is aimed at investigating whether nuclear factor erythrocyte-associated factor 2 (Nrf2) negatively regulated the Nod-like receptor protein 3 (NLRP3) inflammasomes through the thioredoxin 1 (Trx1)/thioredoxin interaction protein (TXNIP) complex. Methods: We determined the optimal hydrogen peroxide (H2O2) concentration, time, and changes in reactive oxygen species (ROS) levels. We also constructed animal models using blue LED irradiation. Then, the expression of Nrf2, TXNIP, Trx1, NLRP3, and inflammation-related factors and proteins, along with the changes in retinal thickness and functional status, was analyzed. Results: The oxidative stress model was established after 1 h intervention with 100 µM H2O2. Nrf2 reduced ROS production, protected the ultrastructure of mitochondria, increased the thickness of the ONL layer, and increased the amplitude of a- and b-wave amplitudes in ERG. Trx1 knockdown increased the production of ROS, damaged the ultrastructure of mitochondria, reduced the thickness of the other ONL layer, and reduced the amplitudes of a- and b-waves in the electroretinogram (ERG). Thus, TXNIP in the cytoplasm activated the inflammasomes. Conclusions: Nrf2 showed antioxidant and anti-inflammatory activity in the H2O2-induced cell stress model and blue LED-induced retinal light damage model. TXNIP transferred from the nucleus to the cytoplasm, activated NLRP3, and aggravated the retinal injury in both the cell stress model and the animal blue LED model. In contrast, Trx1 knockout promoted this process. This study revealed the possible role of the thioredoxin system in developing AMD while also providing newer insights for the future treatment of AMD.


Assuntos
Proteínas de Transporte , Degeneração Macular , Fator 2 Relacionado a NF-E2 , Tiorredoxinas , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Fator de Transcrição de Proteínas de Ligação GA , Humanos , Peróxido de Hidrogênio , Inflamassomos , Inflamação , Degeneração Macular/genética , Degeneração Macular/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Espécies Reativas de Oxigênio , Doenças Retinianas/genética , Doenças Retinianas/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
6.
Vet Parasitol ; 310: 109785, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35994916

RESUMO

Thioredoxin (Trx) is a widespread protein regulator of redox reactions in all organisms. It operates together with NADPH and thioredoxin reductase as a general protein disulfide catalytic system. Recently, Trx has been found to be related to the process by which apicomplexan protozoa invade host cells. In this study, Eimeria tenella thioredoxin (EtTrx1) was identified and its gene structural features, expression levels at different developmental stages, localization in sporozoites, roles in adhesion and invasion, and immunogenicity were investigated. Sequence analysis indicated that EtTrx1 contains a Trx domain with a WCGPC motif in 29-33 aa and a typical Trx fold, and belongs to thioredoxin family. EtTrx1 was detected on the surface of sporozoites using anti-EtTrx1 polyclonal antibodies under non-permeabilized conditions by indirect immunofluorescence assay (IFA) and also in a secretion form. EtTrx1 protein was highly transcribed and expressed in merozoites and sporozoites by quantitative PCR and western blot. The attachment assay showed that the adherence rates of yeast cells expressing EtTrx1 on the surface to host cells were 3.1-fold higher than those of the blank control. Specific anti-EtTrx1 antibodies inhibited the invasion of sporozoites into DF-1 cells. The highest inhibition rate was up to 36.75% compared to the control group. Immunization with recombinant EtTrx1 peptides also showed significant protection against lethal infections in chickens. It could offer moderate protective efficacy (Anticoccidial Index [ACI]: 163.70), induce humoral responses, and be an effective candidate for the development of new vaccines.


Assuntos
Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Animais , Galinhas/parasitologia , Clonagem Molecular , Coccidiose/prevenção & controle , Coccidiose/veterinária , Eimeria tenella/genética , Doenças das Aves Domésticas/parasitologia , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes , Esporozoítos/fisiologia , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
8.
Free Radic Biol Med ; 189: 157-168, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35921994

RESUMO

Radiotherapy is a standard-of-care treatment approach for glioblastoma (GBM) patients, but therapeutic resistance to radiotherapy remains a major challenge. Here we demonstrate that diallyl trisulfide (DATS) directly conjugates with cysteine (C) 32 and C35 (C32/35) residues of thioredoxin 1 (Trx1) through Michael addition reactions. Due to localizing in activity center of Trx1, the conjugation between DATS and C32/35 results in inhibition of Trx1 activity, therefore disturbing thioredoxin system and leading to accumulated levels of reactive oxygen species (ROS). High levels of Trx1 expression are correlated with poor prognosis of glioma patients. Notably, we reveal that DATS synergistically enhances irradiation (IR)-induced ROS accumulation, apoptosis, DNA damage, as well as inhibition of tumor growth of GBM cells. These findings highlight the potential benefits of DATS in sensitizing radiotherapy of GBM patients.


Assuntos
Compostos Alílicos , Glioblastoma , Compostos Alílicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/radioterapia , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sulfetos/farmacologia , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
9.
Proc Natl Acad Sci U S A ; 119(35): e2116505119, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994650

RESUMO

Albuminuria is a hallmark of glomerular disease of various etiologies. It is not only a symptom of glomerular disease but also a cause leading to glomerulosclerosis, interstitial fibrosis, and eventually, a decline in kidney function. The molecular mechanism underlying albuminuria-induced kidney injury remains poorly defined. In our genetic model of nephrotic syndrome (NS), we have identified CHOP (C/EBP homologous protein)-TXNIP (thioredoxin-interacting protein) as critical molecular linkers between albuminuria-induced ER dysfunction and mitochondria dyshomeostasis. TXNIP is a ubiquitously expressed redox protein that binds to and inhibits antioxidant enzyme, cytosolic thioredoxin 1 (Trx1), and mitochondrial Trx2. However, very little is known about the regulation and function of TXNIP in NS. By utilizing Chop-/- and Txnip-/- mice as well as 68Ga-Galuminox, our molecular imaging probe for detection of mitochondrial reactive oxygen species (ROS) in vivo, we demonstrate that CHOP up-regulation induced by albuminuria drives TXNIP shuttling from nucleus to mitochondria, where it is required for the induction of mitochondrial ROS. The increased ROS accumulation in mitochondria oxidizes Trx2, thus liberating TXNIP to associate with mitochondrial nod-like receptor protein 3 (NLRP3) to activate inflammasome, as well as releasing mitochondrial apoptosis signal-regulating kinase 1 (ASK1) to induce mitochondria-dependent apoptosis. Importantly, inhibition of TXNIP translocation and mitochondrial ROS overproduction by CHOP deletion suppresses NLRP3 inflammasome activation and p-ASK1-dependent mitochondria apoptosis in NS. Thus, targeting TXNIP represents a promising therapeutic strategy for the treatment of NS.


Assuntos
Albuminúria , Proteínas de Transporte , Rim , Mitocôndrias , Síndrome Nefrótica , Tiorredoxinas , Fator de Transcrição CHOP , Albuminúria/complicações , Albuminúria/genética , Albuminúria/prevenção & controle , Animais , Apoptose , Proteínas de Transporte/metabolismo , Núcleo Celular/metabolismo , Deleção de Genes , Inflamassomos/metabolismo , Rim/metabolismo , Rim/patologia , MAP Quinase Quinase Quinase 5/metabolismo , Camundongos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Síndrome Nefrótica/complicações , Síndrome Nefrótica/genética , Síndrome Nefrótica/patologia , Síndrome Nefrótica/prevenção & controle , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo , Fator de Transcrição CHOP/deficiência , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
10.
Chem Res Toxicol ; 35(8): 1425-1432, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35862866

RESUMO

9,10-Phenanthrenequinone (9,10-PQ) is a toxicant in diesel exhaust particles and airborne particulate matter ≤2.5 µm in diameter. It is an efficient electron acceptor that readily reacts with dithiol compounds in vitro, resulting in the oxidation of thiol groups and concomitant generation of reactive oxygen species (ROS). However, it remains to be elucidated whether 9,10-PQ interacts with proximal protein dithiols. In the present study, we used thioredoxin 1 (Trx1) as a model of proteins with reactive proximal cysteines and examined whether it reacts with 9,10-PQ in cells and tissues, thereby affecting its catalytic activity and thiol status. Intratracheal injection of 9,10-PQ into mice resulted in protein oxidation and diminished Trx activity in the lungs. Using recombinant wild-type and C32S/C35S Trx1, we found that Cys32 and Cys35 selectively serve as electron donor sites for redox reactions with 9,10-PQ that lead to substantial inhibition of Trx activity. Addition of dithiothreitol restored the Trx activity inhibited by 9,10-PQ. Exposure of cultured cells to 9,10-PQ caused intracellular reactive oxygen species generation that led to protein oxidation, Trx1 dimerization, p38 phosphorylation, and apoptotic cell death. Overexpression of Trx1 blocked these 9,10-PQ-mediated events. These results suggest that the interaction of the reactive cysteines of Trx1 with 9,10-PQ causes oxidative stress, leading to disruption of redox homeostasis.


Assuntos
Elétrons , Tiorredoxinas , Animais , Cisteína/metabolismo , Homeostase , Camundongos , Oxidantes , Oxirredução , Fenantrenos , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo
11.
mBio ; 13(4): e0163922, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35862766

RESUMO

The resurgence of syphilis in the new millennium has called attention to the importance of a vaccine for global containment strategies. Studies with immune rabbit serum (IRS) indicate that a syphilis vaccine should elicit antibodies (Abs) that promote opsonophagocytosis of treponemes by activated macrophages. The availability of three-dimensional models for Treponema pallidum's (Tp) repertoire of outer membrane proteins (OMPs) provides an architectural framework for identification of candidate vaccinogens with extracellular loops (ECLs) as the targets for protective Abs. Herein, we used Pyrococcus furiosus thioredoxin (PfTrx) as a scaffold to display Tp OMP ECLs to interrogate sera and peripheral blood mononuclear cells (PBMCs) from immune rabbits for ECL-specific Abs and B cells. We validated this approach using a PfTrx scaffold presenting ECL4 from BamA, a known opsonic target. Using scaffolds displaying ECLs of the FadL orthologs TP0856 and TP0858, we determined that ECL2 and ECL4 of both proteins are strongly antigenic. Comparison of ELISA and immunoblot results suggested that the PfTrx scaffolds present conformational and linear epitopes. We then used the FadL ECL2 and ECL4 PfTrx constructs as "hooks" to confirm the presence of ECL-specific B cells in PBMCs from immune rabbits. Our results pinpoint immunogenic ECLs of two newly discovered OMPs, while advancing the utility of the rabbit model for circumventing bottlenecks in vaccine development associated with large-scale production of folded OMPs. They also lay the groundwork for production of rabbit monoclonal Abs (MAbs) to characterize potentially protective ECL epitopes at the atomic level. IMPORTANCE Recent identification and structural modeling of Treponema pallidum's (Tp) repertoire of outer membrane proteins (OMPs) represent a critical breakthrough in the decades long quest for a syphilis vaccine. However, little is known about the antigenic nature of these ß-barrel-forming OMPs and, more specifically, their surface exposed regions, the extracellular loops (ECLs). In this study, using Pyrococcus furiosus thioredoxin (PfTrx) as a scaffold to display Tp OMP ECLs, we interrogated immune rabbit sera and peripheral blood mononuclear cells for the presence of antibodies (Abs) and circulating rare antigen-specific B cells. Our results pinpoint immunogenic ECLs of two newly discovered OMPs, while advancing the utility of the rabbit model for surveying the entire Tp OMPeome for promising OMP vaccinogens. This work represents a major advancement toward characterizing potentially protective OMP ECLs and future vaccine studies. Additionally, this strategy could be applied to OMPs of nonspirochetal bacterial pathogens.


Assuntos
Sífilis , Treponema pallidum , Anticorpos Antibacterianos/metabolismo , Vacinas Bacterianas , Epitopos , Humanos , Imunoglobulina G/metabolismo , Leucócitos Mononucleares , Proteínas de Membrana/metabolismo , Sífilis/microbiologia , Tiorredoxinas/metabolismo , Treponema pallidum/genética
12.
Phytomedicine ; 104: 154316, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35820305

RESUMO

BACKGROUND: Celastrol (CEL) has a great potential in the treatment of a wide variety of metabolic diseases. However, whether CEL protects pancreatic ß cells and its underlying mechanism are not yet clear. PURPOSE: This study investigates to determine the effects of CEL on the pathogenesis of pancreatic ß cells damage. METHODS: C57BLKS/Leprdb (db/db) mice and rat insulinoma INS-1 cell line or mouse J774A.1 cell line were used as in vivo and in vitro models for investigating the protective effect of CEL on pancreatic ß cells under high glucose environment and the related mechanism. The phenotypic changes were evaluated by immunofluorescence, immunohistochemical staining, flow cytometry and the measurement of biochemical indexes. The molecular mechanism was explored by biological techniques such as western blotting, qPCR, ChIP-qPCR, co-immunoprecipitation and lentivirus infection. RESULTS: Our results showed that CEL at the high dose (CEL-H, 0.2 mg/kg) protects db/db mice against increased body weight and blood glucose. CEL-H inhibits pancreatic ß cell apoptosis in db/db mice and high glucose-induced INS-1 cells. CEL-H also reduced IL-1ß production in islet macrophages. The further study found that CEL suppressed TXNIP expression and NLRP3 inflammasome activation in pancreatic ß cells and islet macrophages. Importantly, the inhibitory effect of CEL on pancreatic ß cell apoptosis and IL-1ß production was also dependent on TXNIP. Mechanically, CEL inhibits Txnip transcription by promoting the degradation of ChREBP. CONCLUSION: Celastrol inhibits TXNIP expression to protect pancreatic ß cells in vivo and in vitro. Our research pointed out another mechanism by which celastrol functions under the condition leptin signaling is ineffective.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Animais , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Inflamassomos/metabolismo , Camundongos , Triterpenos Pentacíclicos , Ratos , Tiorredoxinas/metabolismo
13.
Biochim Biophys Acta Mol Cell Res ; 1869(10): 119323, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35793738

RESUMO

Thioredoxin reductase (TrxR) is a pivotal regulator of redox homeostasis, while dysregulation of redox homeostasis is a hallmark for cancer cells. Thus, there is considerable potential to inhibit the aberrantly upregulated TrxR in cancer cells to discover selective cancer therapeutic agents. Nevertheless, the structural types of TrxR inhibitors presented currently are still relatively limited. We herein report that PACMA 31, previously reported to inhibit protein disulfide isomerase (PDI), is a potent TrxR inhibitor. PACMA 31 possesses a pharmacophore scaffold that is structurally different from the announced TrxR inhibitors and exhibits effective cytotoxicity against cervical cancer cells. Our results reveal that PACMA 31 selectively inhibits TrxR over the related glutathione reductase (GR) and in the presence of reduced glutathione (GSH). Further studies with mutant enzyme and molecular docking suggest that the propynamide fragment of PACMA 31 interacts covalently with the selenocysteine residue of TrxR. Moreover, PACMA 31 effectively and selectively curbs TrxR activity in cells and further stimulates the production of reactive oxygen species (ROS) at low micromolar concentrations, which in turn triggers the accumulation of oxidized thioredoxin (Trx) and GSSG in cells. Follow-up studies demonstrate that PACMA 31 targets TrxR in cells to induce oxidative stress-mediated cancer cell apoptosis. Our results provide a new structural type of TrxR inhibitor that may serve as a useful probe for investigating the biology of TrxR-implicated pathways, and uncover a new target of PACMA 31 that contributes to it becoming a candidate for cancer treatment.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias , Tiorredoxina Dissulfeto Redutase , Apoptose , Inibidores Enzimáticos/farmacologia , Humanos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Tiorredoxina Dissulfeto Redutase/metabolismo , Tiorredoxina Dissulfeto Redutase/farmacologia , Tiorredoxinas/metabolismo
15.
Nutrients ; 14(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35807771

RESUMO

Acute pancreatitis (AP) is one of the most common causes of hospitalization for gastrointestinal diseases, with high morbidity and mortality. Endoplasmic reticulum stress (ERS) and Gasdermin D (GSDMD) mediate AP, but little is known about their mutual influence on AP. Diosgenin has excellent anti-inflammatory and antioxidant effects. This study investigated whether Diosgenin derivative D (Drug D) inhibits L-arginine-induced acute pancreatitis through meditating GSDMD in the endoplasmic reticulum (ER). Our studies were conducted in a mouse model of L-arginine-induced AP as well as in an in vitro model on mouse pancreatic acinar cells. The GSDMD accumulation in ER was found in this study, which caused ERS of acinar cells. GSDMD inhibitor Disulfiram (DSF) notably decreased the expression of GSDMD in ER and TXNIP/HIF-1α signaling. The molecular docking study indicated that there was a potential interaction between Drug D and GSDMD. Our results showed that Drug D significantly inhibited necrosis of acinar cells dose-dependently, and we also found that Drug D alleviated pancreatic necrosis and systemic inflammation by inhibiting the GSDMD accumulation in the ER of acinar cells via the TXNIP/HIF-1α pathway. Furthermore, the level of p-IRE1α (a marker of ERS) was also down-regulated by Drug D in a dose-dependent manner in AP. We also found that Drug D alleviated TXNIP up-regulation and oxidative stress in AP. Moreover, our results revealed that GSDMD-/- mitigated AP by inhibiting TXNIP/HIF-1α. Therefore, Drug D, which is extracted from Dioscorea zingiberensis, may inhibit L-arginine-induced AP by meditating GSDMD in the ER by the TXNIP /HIF-1α pathway.


Assuntos
Diosgenina , Pancreatite , Doença Aguda , Animais , Apoptose , Arginina/farmacologia , Proteínas de Transporte , Diosgenina/efeitos adversos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Proteínas Serina-Treonina Quinases , Tiorredoxinas/metabolismo
16.
Pharmacol Res ; 182: 106292, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35691540

RESUMO

Diabetic retinopathy (DR) is a chronic microvascular complication of diabetes mellitus (DM). It is a worldwide growing epidemic disease considered to be the leading cause of vision-loss and blindness in people with DM. Redox reactions occurring at the extra- and intracellular levels are essential for the maintenance of cellular homeostasis. Dysregulation of redox homeostasis are implicated in the onset and development of DR. Thioredoxin1 (TRX1) and Thioredoxin2 (TRX2) are cytoplasmic and mitochondrially localized antioxidant proteins ubiquitously expressed in various cells and control cellular reactive oxygen species (ROS) by reducing the disulfides into thiol groups. Thioredoxin-interacting protein (TXNIP) binds to TRX system and inhibits the active reduced form of TRX through disulfide exchange reaction. Recent studies indicate the association of TRX/TXNIP with redox signal transduction pathways including activation of Nod-like receptor pyrin domain containing protein-3 (NLRP3) inflammasome, apoptosis, autophagy/mitophagy, epigenetic modifications in a redox-dependent manner. Thus, it is important to gain a more in-depth understanding about the cellular and molecular mechanisms that links redoxisome and ER/Mitochondrial dysfunction to drive the progression of DR. The purpose of this review is to provide a mechanistic understanding of the complex molecular mechanisms and pathophysiological roles associated with redoxisome, the TRX/TXNIP redox signaling complex under oxidative stress in the development of DR. Also, the molecular targets of FDA approved drugs and clinical trials in addition to effective antioxidant strategies for the treatment of diabetic retinopathy are reviewed.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Antioxidantes/metabolismo , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo
17.
Microvasc Res ; 143: 104396, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35644243

RESUMO

Endothelial dysfunction, hallmarked by an imbalance between vasoconstriction and vasorelaxation, is associated with diabetes. Thioredoxin Interacting protein (TXNIP), controlled by an exquisitely glucose sensitive gene, is increasingly recognized for its role in diabetes. However, the role of TXNIP in modulating diabetes-related endothelial dysfunction remains unclear. To elucidate the role of TXNIP, we generated two novel mouse strains; endothelial-specific TXNIP knockout (EKO) and a Tet-O inducible, endothelial-specific TXNIP overexpression (EKI). Hyperglycemia was induced by streptozotocin (STZ) treatment in floxed control (fl/fl) and EKO mice. Doxycycline (DOX) was given to EKI mice to induce endothelial TXNIP overexpression. The ablation of endothelial TXNIP improved glucose tolerance in EKO mice. Acetylcholine-induced, endothelium-dependent vasorelaxation was impaired in STZ-treated fl/fl mice while this STZ impaired vasorelaxation was attenuated in EKO mice. Hyperglycemia induction of NLRP3 and reductions in Akt and eNOS phosphorylation were also mitigated in EKO mice. Overexpression of endothelial TXNIP did not impair glucose tolerance in DOX-treated EKI mice, however induction of endothelial TXNIP led to impaired vasorelaxation in EKI mice. This was associated with increased NLRP3 and reduced Akt and eNOS activation. In conclusion, deletion of endothelial TXNIP is protective against and overexpression of endothelial TXNIP induces endothelial dysfunction; thus, endothelial TXNIP plays a critical role in modulating endothelial dysfunction.


Assuntos
Endotélio , Hiperglicemia , Tiorredoxinas , Vasodilatação , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Endotélio/metabolismo , Endotélio/fisiopatologia , Glucose , Hiperglicemia/metabolismo , Hiperglicemia/fisiopatologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estreptozocina , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Vasodilatação/genética , Vasodilatação/fisiologia
18.
Neoplasia ; 31: 100815, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35728512

RESUMO

Extracellular adenosine in the tumor microenvironment plays a vital role in cancer development. Specifically, activation of adenosine receptors affects tumor cell growth and adenosine release. We examined the anti-tumor efficacy of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) in animal models, revealing the role of PLAG in inhibiting tumor progression by promoting the degradation of adenosine 2B receptors (A2BRs) in tumors. PLAG induced the expression of thioredoxin-interacting protein (TXNIP), a type of α-arrestin that accelerates A2BR internalization by interacting with A2BR complexes containing ß-arrestin. Engulfed receptors bound to TXNIP were rapidly degraded after E3 ligase recruitment and ubiquitination, resulting in early termination of intracellular signals that promote tumor overgrowth. However, in control cancer cells, A2BRs bound to protein phosphatase 2A and were returned to the cell membrane instead of being degraded, resulting in continuous receptor-mediated signaling by pathways including the Raf-Erk axis, which promotes tumor proliferation. A TXNIP-silenced cell-implanted mouse model and TXNIP knockout (KO) mice were used to verify that PLAG-mediated suppression of tumor progression is dependent on TXNIP expression. Increased tumor growth was observed in TXNIP-silenced cell-implanted mice, and the anti-tumor effects of PLAG, including delayed tumor overgrowth, were greatly reduced. However, the anti-tumor effects of PLAG were observed in cancer cell-implanted TXNIP-KO mice, which indicates that PLAG produces anti-tumor effects by enhancing TXNIP expression in tumor cells. These essential functions of PLAG, including delaying tumor growth via A2BR degradation, suggest innovative directions for anticancer drug development.


Assuntos
Carcinoma Pulmonar de Lewis , Carcinoma Pulmonar de Células não Pequenas , Proteínas de Transporte , Neoplasias Pulmonares , Receptores Purinérgicos P1 , Tiorredoxinas , Adenosina/farmacologia , Animais , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas de Transporte/metabolismo , Diglicerídeos/metabolismo , Diglicerídeos/farmacologia , Camundongos , Receptores Purinérgicos P1/efeitos dos fármacos , Receptores Purinérgicos P1/metabolismo , Tiorredoxinas/metabolismo , Microambiente Tumoral
19.
J Biol Chem ; 298(8): 102183, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35753352

RESUMO

Thioredoxin/glutathione reductase (TXNRD3) is a selenoprotein composed of thioredoxin reductase and glutaredoxin domains. This NADPH-dependent thiol oxidoreductase evolved through gene duplication within the Txnrd family, is expressed in the testes, and can reduce both thioredoxin and glutathione in vitro; however, the function of this enzyme remains unknown. To characterize the function of TXNRD3 in vivo, we generated a strain of mice bearing deletion of Txnrd3 gene. We show that these Txnrd3 knockout mice are viable and without discernable gross phenotypes, and also that TXNRD3 deficiency leads to fertility impairment in male mice. We found that Txnrd3 knockout animals exhibited a lower fertilization rate in vitro, a sperm movement phenotype, and an altered thiol redox status in sperm cells. Proteomic analyses further revealed a broad range of substrates reduced by TXNRD3 during sperm maturation, presumably as a part of sperm quality control. Taken together, these results show that TXNRD3 plays a critical role in male reproduction via the thiol redox control of spermatogenesis.


Assuntos
Proteômica , Sêmen , Tiorredoxina Dissulfeto Redutase/metabolismo , Animais , Fertilidade , Masculino , Camundongos , Oxirredução , Selenoproteínas , Sêmen/metabolismo , Espermatogênese , Compostos de Sulfidrila , Tiorredoxina Dissulfeto Redutase/genética , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
20.
Plant Physiol ; 189(4): 2298-2314, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35736508

RESUMO

Cystathionine-ß-synthase (CBS) domains are found in proteins of all living organisms and have been proposed to play a role as energy sensors regulating protein activities through their adenosyl ligand binding capacity. In plants, members of the CBSX protein family carry a stand-alone pair of CBS domains. In Arabidopsis (Arabidopsis thaliana), CBSX1 and CBSX2 are targeted to plastids where they have been proposed to regulate thioredoxins (TRXs). TRXs are ubiquitous cysteine thiol oxido-reductases involved in the redox-based regulation of numerous enzymatic activities as well as in the regeneration of thiol-dependent peroxidases. In Arabidopsis, 10 TRX isoforms have been identified in plastids and divided into five sub-types. Here, we show that CBSX2 specifically inhibits the activities of m-type TRXs toward two chloroplast TRX-related targets. By testing activation of NADP-malate dehydrogenase and reduction of 2-Cys peroxiredoxin, we found that TRXm1/2 inhibition by CBSX2 was alleviated in the presence of AMP or ATP. We also determined, by pull-down assays, a direct interaction of CBSX2 with reduced TRXm1 and m2 that was abolished in the presence of adenosyl ligands. In addition, we report that, compared with wild-type plants, the Arabidopsis T-DNA double mutant cbsx1 cbsx2 exhibits growth and chlorophyll accumulation defects in cold conditions, suggesting a function of plastidial CBSX proteins in plant stress adaptation. Together, our results show an energy-sensing regulation of plastid TRX m activities by CBSX, possibly allowing a feedback regulation of ATP homeostasis via activation of cyclic electron flow in the chloroplast, to maintain a high energy level for optimal growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Cistationina beta-Sintase/química , Oxirredução , Plastídeos/metabolismo , Compostos de Sulfidrila/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
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