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1.
Cells ; 10(8)2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34440621

RESUMO

The glyoxalase system is critical for the detoxification of advanced glycation end-products (AGEs). AGEs are toxic compounds resulting from the non-enzymatic modification of biomolecules by sugars or their metabolites through a process called glycation. AGEs have adverse effects on many tissues, playing a pathogenic role in the progression of molecular and cellular aging. Due to the age-related decline in different anti-AGE mechanisms, including detoxifying mechanisms and proteolytic capacities, glycated biomolecules are accumulated during normal aging in our body in a tissue-dependent manner. Viewed in this way, anti-AGE detoxifying systems are proposed as therapeutic targets to fight pathological dysfunction associated with AGE accumulation and cytotoxicity. Here, we summarize the current state of knowledge related to the protective mechanisms against glycative stress, with a special emphasis on the glyoxalase system as the primary mechanism for detoxifying the reactive intermediates of glycation. This review focuses on glyoxalase 1 (GLO1), the first enzyme of the glyoxalase system, and the rate-limiting enzyme of this catalytic process. Although GLO1 is ubiquitously expressed, protein levels and activities are regulated in a tissue-dependent manner. We provide a comparative analysis of GLO1 protein in different tissues. Our findings indicate a role for the glyoxalase system in homeostasis in the eye retina, a highly oxygenated tissue with rapid protein turnover. We also describe modulation of the glyoxalase system as a therapeutic target to delay the development of age-related diseases and summarize the literature that describes the current knowledge about nutritional compounds with properties to modulate the glyoxalase system.


Assuntos
Envelhecimento/metabolismo , Senescência Celular , Produtos Finais de Glicação Avançada/metabolismo , Lactoilglutationa Liase/metabolismo , Estresse Fisiológico , Fatores Etários , Envelhecimento/patologia , Animais , Senescência Celular/efeitos dos fármacos , Dieta , Suplementos Nutricionais , Glicosilação , Humanos , Compostos Fitoquímicos/farmacologia , Carbonilação Proteica , Proteólise , Estresse Fisiológico/efeitos dos fármacos , Especificidade por Substrato
2.
Redox Biol ; 45: 102057, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34198071

RESUMO

Methylglyoxal (MG) is a reactive and cytotoxic α-dicarbonyl byproduct of glycolysis. Our bodies have several bio-defense systems to detoxify MG, including an enzymatic system by glyoxalase (GLO) 1 and GLO2. We identified a subtype of schizophrenia patients with novel mutations in the GLO1 gene that results in reductions of enzymatic activity. Moreover, we found that vitamin B6 (VB6) levels in peripheral blood of the schizophrenia patients with GLO1 dysfunction are significantly lower than that of healthy controls. However, the effects of GLO1 dysfunction and VB6 deficiency on the pathophysiology of schizophrenia remains poorly understood. Here, we generated a novel mouse model for this subgroup of schizophrenia patients by feeding Glo1 knockout mice VB6-deficent diets (KO/VB6(-)) and evaluated the combined effects of GLO1 dysfunction and VB6 deficiency on brain function. KO/VB6(-) mice accumulated homocysteine in plasma and MG in the prefrontal cortex (PFC), hippocampus, and striatum, and displayed behavioral deficits, such as impairments of social interaction and cognitive memory and a sensorimotor deficit in the prepulse inhibition test. Furthermore, we found aberrant gene expression related to mitochondria function in the PFC of the KO/VB6(-) mice by RNA-sequencing and weighted gene co-expression network analysis (WGCNA). Finally, we demonstrated abnormal mitochondrial respiratory function and subsequently enhanced oxidative stress in the PFC of KO/VB6(-) mice in the PFC. These findings suggest that the combination of GLO1 dysfunction and VB6 deficiency may cause the observed behavioral deficits via mitochondrial dysfunction and oxidative stress in the PFC.


Assuntos
Lactoilglutationa Liase , Esquizofrenia , Deficiência de Vitamina B 6 , Animais , Humanos , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Córtex Pré-Frontal/metabolismo , Esquizofrenia/genética
3.
Clin Nutr ; 40(5): 2654-2662, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33933731

RESUMO

AIMS: Dicarbonyl compounds contribute to the formation of advanced glycation endproducts (AGEs) and the development of insulin resistance and vascular complications. Dicarbonyl stress may already be detrimental in obesity. We evaluated whether diet-induced weight loss can effectively reverse dicarbonyl stress in abdominally obese men. MATERIALS AND METHODS: Plasma samples were collected from lean (n = 25) and abdominally obese men (n = 52) in the fasting state, and during a mixed meal test (MMT). Abdominally obese men were randomized to 8 weeks of dietary weight loss or habitual diet, followed by a second MMT. The α-dicarbonyls methylglyoxal (MGO), glyoxal (GO) and 3-deoxyglucosone (3-DG) and AGEs were measured by UPLC-MS/MS. Skin autofluorescence (SAF) was measured using the AGE reader. T-tests were used for the cross-sectional analysis and ANCOVA to assess the treatment effect. RESULTS: Postprandial glucose, MGO and 3-DG concentrations were higher in obese men as compared to lean men (p < 0.05 for all). Fasting dicarbonyls, AGEs, and SAF were not different between lean and obese men. After the weight loss intervention, fasting MGO levels tended to decrease by 25 nmol/L (95%-CI: -51-0.5; p = 0.054). Postprandial dicarbonyls were decreased after weight loss as compared to the control group: iAUC of MGO decreased by 57% (5280 nmol/L∙min; 95%-CI: 33-10526; p = 0.049), of GO by 66% (11,329 nmol/L∙min; 95%-CI: 495-22162; p = 0.041), and of 3-DG by 45% (20,175 nmol/L∙min; 95%-CI: 5351-35000; p = 0.009). AGEs and SAF did not change significantly after weight loss. CONCLUSION: Abdominal obesity is characterized by increased postprandial dicarbonyl stress, which can be reduced by a weight loss intervention. Registered under ClinicalTrials.gov Identifier no. NCT01675401.


Assuntos
Dieta Redutora , Obesidade Abdominal/dietoterapia , Período Pós-Prandial , Estresse Fisiológico , Perda de Peso/fisiologia , Adulto , Aldeído-Desidrogenase Mitocondrial/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Estudos Transversais , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Masculino
4.
Chem Biol Interact ; 345: 109511, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33989593

RESUMO

Methylglyoxal is a dicarbonyl compound recruited as a potential cytotoxic marker, initially presents in cells and considered as a metabolite of the glycolytic pathway. Our aim is to demonstrate the inhibitory effect of 3, 3'-[3-(5-chloro-2-hydroxyphenyl)-3-oxopropane-1, 1-diyl] Bis (4-hydroxycoumarin) on the glyoxalase system, and indirectly its anticancer activity. The docking of OT-55 was conducted by using Flexible docking protocol, ChiFlex and libdock tools inside the active site of Glo-I indicated that both hydrogen bonding and hydrophobic interactions contributed significantly in establishing potent binding with the active site which is selected as a strong inhibitor with high scoring values and maximum Gibbs free energy. Coumarin-liposome formulation was characterized and evaluated in vivo against chemically induced hepatocarcinoma in Wistar rats. After Diethylnitrosamine (DEN) induction, microscopic assessment was realized; precancerous lesions were developed showing an increase of both tumor-associated lymphocyte and multiple tumor acini supported by the blood investigation. Our finding also suggested a preferential uptake of liposomes respectively in liver, kidney, lung, brain and spleen in the DEN-treated animals. OT-55 has also been shown to inhibit the activity of Glo-I in vitro as well as in DEN-treated rats. An abnormal high level of MGO of up to 50% was recorded followed by a reduction in glucose consumption and lactate dehydrogenase production validated in the positive control. MGO generates apoptosis as depicted by focal hepatic lesions. Also, no deleterious effects in the control group were observed after testing our coumarin but rather a vascular reorganization leading to nodular regenerative hyperplasia. Involved in the detoxification process, liver GSH is restored in intoxicated rats, while no changes are seen between controls. At the endothelial cell, OT-55 appears to modulate the release of NO only in the DEN-treated group. OT-55 would behave both as an anticancer agent but also as an angiogenic factor regarding results obtained.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Espaço Intracelular/efeitos dos fármacos , Lactoilglutationa Liase/antagonistas & inibidores , Neoplasias Hepáticas/patologia , Modelos Moleculares , Aldeído Pirúvico/metabolismo , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transporte Biológico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/metabolismo , Lactoilglutationa Liase/química , Lactoilglutationa Liase/metabolismo , Lipossomos/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Terapia de Alvo Molecular , Conformação Proteica , Ratos , Ratos Wistar , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Food Chem Toxicol ; 153: 112244, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33930484

RESUMO

Methylglyoxal (MGO), a cytotoxic byproduct of glycolysis in biological systems, can induce endothelial cells dysfunction, implicated in diabetic vascular complications. Pterostilbene (PTS), a naturally occurring resveratrol derivative, is involved in various pharmacological activities. This study aimed to explore the effects of PTS on MGO induced cytotoxicity in human umbilical vein endothelial cells (HUVECs) and the underlying mechanisms for the first time. In the current study, it has been demonstrated that PTS could enhance the level of glyoxalase 1 (GLO-1) and elevate glutathione (GSH) content to active the glyoxalase system, resulting in elimination of the toxic MGO as well as advanced glycation end products (AGEs) in HUVECs. Meanwhile, PTS could also suppress oxidative stress and thus exert cytoprotective effects by elevating Nrf2 nuclear translocation and the corresponding down-stream antioxidant enzymes in MGO induced HUVECs. In addition, PTS could alleviate MGO induced apoptosis in HUVECs via inhibition of oxidative stress and associated downstream mitochondria-dependent signaling apoptotic cascades, as characterized by preventing caspases family activation. Taken together, these findings suggest that PTS could protect against MGO induced endothelial cell cytotoxicity by regulating glyoxalase, oxidative stress and apoptosis, suggesting that PTS could be beneficial in the treatment of diabetic vascular complications.


Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Lactoilglutationa Liase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Aldeído Pirúvico/toxicidade , Estilbenos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Lactoilglutationa Liase/genética , Espécies Reativas de Oxigênio
6.
Biochem Biophys Res Commun ; 549: 61-66, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33667710

RESUMO

The glyoxalase system is a ubiquitous detoxification pathway of methylglyoxal, a cytotoxic byproduct of glycolysis. Actively proliferating cells, such as cancer cells, depend on their energy metabolism for glycolysis. Therefore, the glyoxalase system has been evaluated as a target of anticancer drugs. The malaria sporozoite, which is the infective stage of the malaria parasite, actively proliferates and produces thousands of merozoites within 2-3 days in hepatocytes. This is the first step of infection in mammalian hosts. The glyoxalase system appears to play an important role in this active proliferation stage of the malaria parasite in hepatocytes. In this study, we aimed to dissect the role of the glyoxalase system in malaria parasite proliferation in hepatocytes to examine its potential as a target of malaria prevention using a reverse genetics approach. The malaria parasite possesses a glyoxalase system, comprised of glyoxalases and GloI-like protein, in the cytosol and apicoplast. We generated cytosolic glyoxalase II (cgloII) knockout, apicoplast targeted glyoxalase gloII (tgloII) knockout, and cgloII and tgloII double-knockout parasites and performed their phenotypic analysis. We did not observe any defects in the cgloII or tgloII knockout parasites. In contrast, we observed approximately 90% inhibition of the liver-stage proliferation of cgloII and tgloII double-knockout parasites in vivo. These findings suggest that although the glyoxalase system is dispensable, it plays an important role in parasite proliferation in hepatocytes. Additionally, the results indicate a complementary relationship between the cytosolic and apicoplast glyoxalase pathways. We expect that the parasite utilizes a system similar to that observed in cancer cells to enable its rapid proliferation in hepatocytes; this process could be targeted in the development of novel strategies to prevent malaria.


Assuntos
Lactoilglutationa Liase/metabolismo , Estágios do Ciclo de Vida , Fígado/parasitologia , Redes e Vias Metabólicas , Plasmodium berghei/enzimologia , Plasmodium berghei/crescimento & desenvolvimento , Animais , Feminino , Técnicas de Inativação de Genes , Malária/parasitologia , Malária/patologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Parasitos/metabolismo
7.
J Cell Physiol ; 236(8): 5620-5632, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33687075

RESUMO

Lung adenocarcinoma (LUAD) is the most important histological type of lung cancer. We aimed to identify the role of long noncoding RNA family with sequence similarity 201-member A (FAM201A) in the occurrence and development of LUAD. The expressions of FAM201A in LUAD tissues and cells were determined via reverse transcription-quantitative polymerase chain reaction. The effects of FAM201A knockdown on LUAD cell malignant phenotypes were examined by cell counting kit-8, 5-ethynyl-2'-deoxyuridine, flow cytometry, transwell assay and wound healing assay. The underlying mechanism by which FAM201A regulated LUAD progression was also studied. Nude mice LUAD xenograft model was constructed, to explore the in vivo effect of FAM201A. Our results showed that the FAM201A expression in LUAD tissues and cell lines was notably higher than normal tissues and cells. Downregulation of FAM201A suppressed the cell proliferation, migration and invasion and promoted the cell apoptosis in LUAD cells. While, FAM201A overexpression showed tumorigenesis effect on LUAD cells. Moreover, we demonstrated that FAM201A affected LUAD progression via targeting miR-7515 to promote GLO1 expression. FAM201A downregulation also suppressed LUAD development in vivo experiment. Our results indicated that FAM201A was an oncogene in LUAD and might be a novel therapeutic target for LUAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Humanos , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos Nus
8.
J Ethnopharmacol ; 272: 113945, 2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-33617966

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Most Aristolochiaceae plants are prohibited due to aristolochic acid nephropathy (AAN), except Xixin (Asarum spp.). Xixin contains trace amounts of aristolochic acid (AA) and is widely used in Traditional Chinese Medicine. Methylglyoxal and d-lactate are regarded as biomarkers for nephrotoxicity. AIM OF THE STUDY: The use of Xixin (Asarum spp.) is essential and controversial. This study aimed to evaluate tubulointerstitial injury and interstitial renal fibrosis by determining urinary methylglyoxal and d-lactate after withdrawal of low-dose AA in a chronic mouse model. MATERIALS AND METHODS: C3H/He mice in the AA group (n = 24/group) were given ad libitum access to distilled water containing 3 µg/mL AA (0.5 mg/kg/day) for 56 days and drinking water from days 57 to 84. The severity of tubulointerstitial injury and fibrosis were evaluated using the tubulointerstitial histological score (TIHS) and Masson's trichrome staining. Urinary and serum methylglyoxal were determined by high-performance liquid chromatography (HPLC); urinary d-lactate were determined by column-switching HPLC. RESULTS: After AA withdrawal, serum methylglyoxal in the AA group increased from day 56 (429.4 ± 48.3 µg/L) to 84 (600.2 ± 99.9 µg/L), and peaked on day 70 (878.3 ± 171.8 µg/L; p < 0.05); TIHS and fibrosis exhibited similar patterns. Urinary methylglyoxal was high on day 56 (3.522 ± 1.061 µg), declined by day 70 (1.583 ± 0.437 µg) and increased by day 84 (2.390 ± 0.130 µg). Moreover, urinary d-lactate was elevated on day 56 (82.10 ± 18.80 µg) and higher from day 70 (201.10 ± 90.82 µg) to 84 (193.28 ± 61.32 µg). CONCLUSIONS: Methylglyoxal is induced after AA-induced tubulointerstitial injury, so methylglyoxal excretion and metabolism may be a detoxification and repair strategy. A low cumulative AA dose is the key factor that limits tubulointerstitial injury and helps to repair. Thus, AA-containing herbs, especially Xixin, should be used at low doses for short durations (less than one month).


Assuntos
Ácidos Aristolóquicos/toxicidade , Ácidos Aristolóquicos/uso terapêutico , Medicamentos de Ervas Chinesas/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Nefropatias/induzido quimicamente , Ácido Láctico/análise , Aldeído Pirúvico/análise , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Fibrose/induzido quimicamente , Fibrose/patologia , Nefropatias/sangue , Nefropatias/patologia , Nefropatias/urina , Túbulos Renais/patologia , Ácido Láctico/urina , Lactoilglutationa Liase/metabolismo , Camundongos Endogâmicos C3H , Aldeído Pirúvico/sangue , Aldeído Pirúvico/urina
9.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562355

RESUMO

Synphilin-1 has previously been identified as an interaction partner of α-Synuclein (αSyn), a primary constituent of neurodegenerative disease-linked Lewy bodies. In this study, the repercussions of a disrupted glyoxalase system and aldose reductase function on Synphilin-1 inclusion formation characteristics and cell growth were investigated. To this end, either fluorescent dsRed-tagged or non-tagged human SNCAIP, which encodes the Synphilin-1 protein, was expressed in Saccharomyces cerevisiae and Schizosaccharomyces pombe yeast strains devoid of enzymes Glo1, Glo2, and Gre3. Presented data shows that lack of Glo2 and Gre3 activity in S. cerevisiae increases the formation of large Synphilin-1 inclusions. This correlates with enhanced oxidative stress levels and an inhibitory effect on exponential growth, which is most likely caused by deregulation of autophagic degradation capacity, due to excessive Synphilin-1 aggresome build-up. These findings illustrate the detrimental impact of increased oxidation and glycation on Synphilin-1 inclusion formation. Similarly, polar-localised inclusions were observed in wild-type S. pombe cells and strains deleted for either glo1+ or glo2+. Contrary to S. cerevisiae, however, no growth defects were observed upon expression of SNCAIP. Altogether, our findings show the relevance of yeasts, especially S. cerevisiae, as complementary models to unravel mechanisms contributing to Synphilin-1 pathology in the context of neurodegenerative diseases.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Lactoilglutationa Liase/antagonistas & inibidores , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Glicosilação , Humanos , Corpos de Inclusão , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Oxirredução , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
10.
J Leukoc Biol ; 109(3): 605-619, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32678947

RESUMO

The highly reactive compound methylglyoxal (MG) can cause direct damage to cells and tissues by reacting with cellular macromolecules. MG has been identified as a biomarker associated with increased sepsis-induced mortality. Patients undergoing septic shock have significantly elevated circulating MG levels compared to postoperative patients and healthy controls. Furthermore, MG has been implicated in the development of type II diabetes mellitus and Alzheimer's disease. Because MG is generated during glycolysis, we hypothesized that MG may be produced by classically activated (M1) macrophages, possibly contributing to the inflammatory response. LPS and IFN-γ-treated macrophages acquired an M1 phenotype (as evidenced by M1 markers and enhanced glycolysis) and formed MG adducts, MG-H1, MG-H2, and MG-H3, which were detected using antibodies specific for MG-modified proteins (methylglyoxal 5-hydro-5-methylimidazolones). MG adducts were also increased in the lungs of LPS-treated mice. Macrophages treated with LPS and IFN-γ also exhibited decreased expression of glyoxalase 1 (Glo1), an enzyme that metabolizes MG. Concentrations of exogenous, purified MG > 0.5 mM were toxic to macrophages; however, a nontoxic dose of 0.3 mM induced TNF-α and IL-1ß, albeit to a lesser extent than LPS stimulation. Despite prior evidence that MG adducts may signal through "receptor for advanced glycation endproducts" (RAGE), MG-mediated cell death and cytokine induction by exogenous MG was RAGE-independent in primary macrophages. Finally, RAGE-deficient mice did not exhibit a significant survival advantage following lethal LPS injection. Overall, our evidence suggests that MG may be produced by M1 macrophages during sepsis, following IFN-γ-dependent down-regulation of Glo1, contributing to over-exuberant inflammation.


Assuntos
Inflamação/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo , Aldeído Pirúvico/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Receptor 4 Toll-Like/metabolismo , Aerobiose , Animais , Morte Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Glicólise/efeitos dos fármacos , Guanidinas/farmacologia , Inflamação/patologia , Interferon gama/farmacologia , Lactoilglutationa Liase/metabolismo , Pulmão/patologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Fenótipo , Aldeído Pirúvico/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Soroalbumina Bovina , Regulação para Cima/efeitos dos fármacos
11.
Ecotoxicol Environ Saf ; 209: 111784, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33316727

RESUMO

Cysteine (Cys) is incorporated into several compounds which are involved in detoxification of heavy metals. It is evident from recent studies that Cys is effective in alleviating the toxicity of heavy metals. Nevertheless, little is known about the Cys-mediated alleviation of chromium (Cr) toxicity. In our study, the impacts of exogenous Cys on Cr-stressed maize (Zea mays L.) were examined by using physiological and proteomic analyses. The results showed that Cr (100 µM) increased the accumulation of hydrogen peroxide, decreased cell viability, enhanced lipid peroxidation and consequently inhibited plant growth. The application of Cys (500 µM) attenuated the adverse effects of Cr on seedling growth. Cys supplementation to Cr treated plants decreased Cr accumulation in the shoots and increased Cr accumulation in roots. Cys treatment also modulated the activities of antioxidant enzymes and increased endogenous Cys content. Sixty proteins in root tissue were significantly affected by exogenous Cys under Cr stress using two-dimensional electrophoresis. Forty-six differentially expressed proteins were successfully identified by MALDI-TOF/TOF mass spectrometry. These differentially expressed proteins were involved in various biological pathways such as stress response (41.3%), energy and carbohydrate metabolism (21.7%), protein metabolism (6.5%), amino acid metabolism (6.5%), and others of unknown functions. The defense response-related proteins including glutathione peroxidase, glutathione S-transferases, pathogenesis-related proteins, glyoxalases and superoxide dismutase were differently regulated by Cys suggesting their roles in the Cys-mediated Cr tolerance.


Assuntos
Antioxidantes/farmacologia , Cromo/toxicidade , Cisteína/farmacologia , Poluentes do Solo/toxicidade , Zea mays/fisiologia , Antioxidantes/metabolismo , Cromo/metabolismo , Cisteína/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Lactoilglutationa Liase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Proteômica , Plântula/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Zea mays/metabolismo
12.
Inorg Chem ; 60(1): 303-314, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33315368

RESUMO

Glyoxalase I (GlxI) is an important enzyme that catalyzes the detoxification of methylglyoxal (MG) with the help of glutathione (H-SG). It is currently unclear whether MG and H-SG are substrates of GlxI or whether the enzyme processes hemithioacetal (HTA), which is nonenzymatically formed from MG and H-SG. Most previous studies have concentrated on the latter mechanism. Here, we study the two-substrate reaction mechanism of GlxI from humans (HuGlxI) and corn (ZmGlxI), which are Zn(II)-active and -inactive, respectively. Hybrid quantum mechanics/molecular mechanics calculations were used to obtain geometrical structures of the stationary points along reaction paths, and big quantum mechanical systems with more than 1000 atoms and free-energy perturbations were used to improve the quality of the calculated energies. We studied, on an equal footing, all reasonable reaction paths to the S- and R-enantiomers of HTA from MG and H-SG (the latter was considered in two different binding modes). The results indicate that the MG and H-SG reaction in both enzymes can follow the same path to reach S-HTA. However, the respective overall barriers and reaction energies are different for the two enzymes (6.1 and -9.8 kcal/mol for HuGlxI and 15.7 and -2.2 kcal/mol for ZmGlxI). The first reaction step to produce S-HTA is facilitated by a crystal water molecule that forms hydrogen bonds with a Glu and a Thr residue in the active site. The two enzymes also follow similar paths to R-HTA. However, the reactions reach a deprotonated and protonated R-HTA in the human and corn enzymes, respectively. The production of deprotonated R-HTA in HuGlxI is consistent with other theoretical and experimental works. However, our calculations show a different behavior for ZmGlxI (both S- and R-HTA can be formed in the enzyme with the alcoholic proton on HTA). This implies that Glu-144 of corn GlxI is not basic enough to keep the alcoholic proton. In HuGlxI, the two binding modes of H-SG that lead to S- and R-HTA are degenerate, but the barrier leading to R-HTA is lower than the barrier to S-HTA. On the other hand, ZmGlxI prefers the binding mode, which produces S-HTA; this observation is consistent with experiments. Based on the results, we present a modification for a previously proposed two-substrate reaction mechanism for ZmGlxI.


Assuntos
Lactoilglutationa Liase/química , Teoria Quântica , Humanos , Lactoilglutationa Liase/metabolismo , Simulação de Dinâmica Molecular , Estrutura Molecular , Zea mays/enzimologia
13.
J Surg Res ; 257: 501-510, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916503

RESUMO

BACKGROUND: Breast cancer is a familiar malignant tumor, which is a great threat to women's life. Long noncoding RNA Opa interacting protein 5-antisense RNA 1 (OIP5-AS1) has been reported to be associated with numerous cancers. This study aimed to explore the role of OIP5-AS1 and the mechanism of its action in the progression of breast cancer. METHODS: The expression of OIP5-AS1 and miR-216a-5p was detected by quantitative real-time polymerase chain reaction. Cell proliferation, apoptosis, migration, or invasion was assessed by 4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, flow cytometry, or transwell assay, respectively. The binding sites were predicted by bioinformatics tool starBase2.0 (http://starbase.sysu.edu.cn/starbase2/index.php). The interaction between miR-216a-5p and OIP5-AS1 or glyoxalase 1 (GLO1) was confirmed by dual-luciferase reporter assay. The expression of GLO1 was quantified by Western blot. Nude mouse tumorigenicity assays were conducted to verify the role of OIP5-AS1 in vivo. RESULTS: OIP5-AS1 and GLO1 were highly expressed in both clinical tumor tissues and cell lines, whereas miR-216a-5p was downregulated. Knockdown of OIP5-AS1 suppressed proliferation, migration, and invasion but promoted apoptosis of breast cancer cells. MiR-216a-5p was a target of OIP5-AS1 and interacted with GLO1. MiR-216a-5p inhibition or GLO1 overexpression reversed the effects of OIP5-AS1 knockdown on the development of breast cancer cells. OIP5-AS1 knockdown depleted tumor growth in vivo. CONCLUSIONS: OIP5-AS1 knockdown suppressed the progression of breast cancer by inducing GLO1 expression via competitively binding to miR-216a-5p, suggesting that OIP5-AS1 was a hopeful biomarker for the therapy of breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Lactoilglutationa Liase/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Camundongos Nus
14.
Plant Signal Behav ; 15(12): 1824697, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32985921

RESUMO

In this research, the lettuce high-temperature-sensitive variety Beisan San 3 was used as a test material. The effects of exogenous spermidine (Spd) on membrane lipid peroxidation, the antioxidant system, the ascorbic acid-glutathione (AsA-GSH) system and the glyoxalase (Glo) system in lettuce seedlings under high-temperature stress were studied by spraying either 1 mM spermidine or ionized water as a control. The results showed that, under high-temperature stress, the growth of lettuce seedlings was weak, and the dry weight (DW) and fresh weight (FW) were reduced by 68.9% and 82%, respectively, compared with those of the normal-temperature controls. In addition, the degree of membrane lipid peroxidation increased, and the reactive oxygen species (ROS) level increased, both of which led to a significant increase in malondialdehyde (MDA) content and lipoxygenase (LOX) activity. Under high-temperature stress, the activity of superoxide dismutase (SOD) decreased, the activities of peroxidase (POD) and catalase (CAT) increased first but then decreased, and the activity of ascorbic acid peroxidase (APX) decreased first but then increased. Glutathione reductase (GR) activity, ascorbic acid (AsA) and glutathione (GSH) content showed an upward trend under high-temperature stress. The activities of glyoxalase (GloI and GloII) in the lettuce seedling leaves increased significantly under high-temperature stress. In contrast, the application of exogenous Spd alleviated the oxidative damage to the lettuce seedlings, which showed a decrease in MDA content and LOX activity and an increase in SOD, POD, CAT, APX, GR, GloI, and GloII activities. In addition, the antioxidant AsA and GSH contents also increased to varying degrees. It can be seen from the results that high temperature stress leads to an increase in the level of ROS and cause peroxidation in lettuce seedlings, and exogenous Spd can enhance the ability of lettuce seedlings to withstand high temperature by enhancing the antioxidant system, glyoxalase system and AsA-GSH cycle system.


Assuntos
Antioxidantes/farmacologia , Temperatura Alta , Lactoilglutationa Liase/metabolismo , Alface/enzimologia , Plântula/enzimologia , Espermidina/farmacologia , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Lipoxigenase/metabolismo , Malondialdeído/metabolismo , Lipídeos de Membrana/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo
15.
Cell Rep ; 32(12): 108160, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32966793

RESUMO

The glyoxalase system is a highly conserved and ubiquitously expressed enzyme system, which is responsible for the detoxification of methylglyoxal (MG), a spontaneous by-product of energy metabolism. This study is able to show that a phosphorylation of threonine-107 (T107) in the (rate-limiting) Glyoxalase 1 (Glo1) protein, mediated by Ca2+/calmodulin-dependent kinase II delta (CamKIIδ), is associated with elevated catalytic efficiency of Glo1 (lower KM; higher Vmax). Additionally, we observe proteasomal degradation of non-phosphorylated Glo1 via ubiquitination does occur more rapidly as compared with native Glo1. The absence of CamKIIδ is associated with poor detoxification capacity and decreased protein content of Glo1 in a murine CamKIIδ knockout model. Therefore, phosphorylation of T107 in the Glo1 protein by CamKIIδ is a quick and precise mechanism regulating Glo1 activity, which is experimentally linked to an altered Glo1 status in cancer, diabetes, and during aging.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Lactoilglutationa Liase/metabolismo , Fosfotreonina/metabolismo , Proteômica , Envelhecimento/patologia , Animais , Linhagem Celular , Diabetes Mellitus/enzimologia , Diabetes Mellitus/patologia , Humanos , Inativação Metabólica , Cinética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/enzimologia , Neoplasias/patologia , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Aldeído Pirúvico/metabolismo
16.
Pharmacol Res ; 161: 105198, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32942016

RESUMO

Methylglyoxal was shown to impair adipose tissue capillarization and insulin sensitivity in obese models. We hypothesized that glyoxalase-1 (GLO-1) activity could be diminished in the adipose tissue of type 2 diabetic obese patients. Moreover, we assessed whether such activity could be increased by GLP-1-based therapies in order to improve adipose tissue capillarization and insulin sensitivity. GLO-1 activity was assessed in visceral adipose tissue of a cohort of obese patients. The role of GLP-1 in modulating GLO-1 was assessed in type 2 diabetic GK rats submitted to sleeve gastrectomy or Liraglutide treatment, in the adipose tissue angiogenesis assay and in the HUVEC cell line. Glyoxalase-1 activity was decreased in visceral adipose tissue of pre-diabetic and diabetic obese patients, together with other markers of adipose tissue dysfunction and correlated with increased HbA1c levels. Decreased adipose tissue GLO-1 levels in GK rats were increased by sleeve gastrectomy and Liraglutide, being associated with overexpression of angiogenic and vasoactive factors, as well as insulin receptor phosphorylation (Tyr1161). Moreover, GLP-1 increased adipose tissue capillarization and HUVEC proliferation in a glyoxalase-dependent manner. Lower adipose tissue GLO-1 activity was observed in dysmetabolic patients, being a target for GLP-1 in improving adipose tissue capillarization and insulin sensitivity.


Assuntos
Tecido Adiposo/irrigação sanguínea , Capilares/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Incretinas/farmacologia , Resistência à Insulina , Lactoilglutationa Liase/metabolismo , Liraglutida/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Adulto , Idoso , Animais , Capilares/enzimologia , Capilares/fisiopatologia , Células Cultivadas , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Feminino , Gastrectomia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/enzimologia , Obesidade/fisiopatologia , Obesidade/cirurgia , Ratos Wistar , Transdução de Sinais
17.
Life Sci ; 258: 118196, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32763295

RESUMO

AIM: The pharmacological properties of pentoxifylline have been re-evaluated, particularly in chronic kidney disease in diabetes, favored by its anti-inflammatory action. Definitive evidences of renal outcomes are lacking, which indicates the need for investigation of novel mechanisms of action of pentoxifylline. We postulated that components associated with the metabolism of advanced glycation end products (AGEs) may be modulated by pentoxifylline, which consequently decreases the detrimental effects of obesity on kidneys. MAIN METHODS: C57BL-6J mice were fed a high-fat diet for 14 weeks and treated with 50 mg/kg pentoxifylline during the last 7 weeks. Changes in the renal levels of AGE metabolism-associated components were investigated, with particular focus on the receptor for AGEs (RAGE), its downstream components, and components related to AGE detoxification, including glyoxalase 1 (GLO 1). KEY FINDINGS: Pentoxifylline reduced body weight gain, improved insulin sensitivity and glucose tolerance, downregulated biomarkers of glycoxidative stress, and enhanced plasma paraoxonase 1 activity. In the kidneys, pentoxifylline inhibited glomerular expansion, lipid deposition, reduced pro-inflammatory cytokine levels, and induced the activation of AMP-activated protein kinase. Pentoxifylline inhibited the renal accumulation of AGEs and reduced the levels of RAGE and its downstream components, and consequently mitigated oxidative stress and apoptosis. Pentoxifylline also increased the renal levels of GLO 1 and the activities of antioxidant enzymes. Urinary albumin levels were observed to be lowered, which reconfirmed the antialbuminuric effects of pentoxifylline. SIGNIFICANCE: The novel mechanisms of action help explain the renoprotective effects of pentoxifylline and the attenuation of obesity-associated renal complications related to glycoxidative stress.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Glicólise/efeitos dos fármacos , Rim/patologia , Lactoilglutationa Liase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pentoxifilina/farmacologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Rim/efeitos dos fármacos , Camundongos Obesos , Transdução de Sinais/efeitos dos fármacos
18.
Plant Physiol Biochem ; 155: 683-696, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32861035

RESUMO

The accumulation of a metabolic by product - methylglyoxal above a minimal range can be highly toxic in all organisms. Stress induced elevation in methylglyoxal inactivates proteins and nucleic acids. Glutathione dependent glyoxalase enzymes like glyoxalase I and glyoxalase II together with glutathione independent glyoxalase III play inevitable role in methylglyoxal detoxification. Glyoxalase genes are generally conserved but with obvious exceptions. Mangroves being potent harsh land inhabitants, their internal organelles are constantly been exposed to elevated levels of methylglyoxal. First and foremost it is important to detect the presence of glyoxalases in mangroves. De novo transcriptome analysis of mangrove species Rhizophora mucronata Lam., identified eleven putative glyoxalase proteins (RmGLYI-1 to 5, RmGLYII-1 to 5 and RmGLYIII). Molecular characterization proposed PLN02300 or PLN02367 as the key domains of RmGLYI proteins. They possess molecular weight ranging from 26.45 to 32.53 kDa and may localize in cytosol or chloroplast. RmGLYII proteins of molecular weight 28.64-36 kDa, carrying PLN02398 or PLN02469 domains are expected to be localized in diverse cellular compartments. Cytosolic RmGLYIII with DJ-1/PfpI domain carries a molecular weight 26.4 kDa. Detailed structural analysis revealed monomeric nature of RmGLYI-1 and RmGLYII-1 whereas RmGLYIII is found to be homodimer. Molecular phylogenetic analysis and multiple sequence alignment specified conserved metal ion/substrate binding residues of RmGLY proteins. Estimation of relative expression of glyoxalases under salt stress indicated the prominence of RmGLYI and RmGLYII over RmGLYIII. The aforementioned prominence is supported by salt induced expression difference of glutathione metabolic enzymes and glutathione regulated transporter protein.


Assuntos
Glutationa/metabolismo , Lactoilglutationa Liase/metabolismo , Proteínas de Plantas/metabolismo , Rhizophoraceae/enzimologia , Tioléster Hidrolases/metabolismo , Perfilação da Expressão Gênica , Filogenia , Aldeído Pirúvico/metabolismo , Rhizophoraceae/genética , Sais , Transcriptoma
19.
Plant Signal Behav ; 15(11): 1811527, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32835595

RESUMO

Methylglyoxal (MG), a cytotoxic oxygenated short aldehyde, is a by-product of various metabolic reactions in plants, including glycolysis. The basal level of MG in plants is low, whereby it acts as an essential signaling molecule regulating multiple cellular processes. However, hyperaccumulation of MG under stress conditions is detrimental for plants as it inhibits multiple developmental processes, including seed germination, photosynthesis, and root growth. The evolutionarily conserved glyoxalase system is critical for MG detoxification, and it comprises of two-enzymes, the glyoxalase-I and glyoxalase-II. Here, we report the functional characterization of six putative glyoxalase-I genes from date palm (Phoenix dactylifera L.) (PdGLX1), by studying their gene expression under various environmental stress conditions and investigating their function in bacteria (Escherichia coli) and yeast (Saccharomyces cerevisiae) mutant cells. The putative PdGLX1 genes were initially identified using computational methods and cloned using molecular tools. The PdGLX1 gene expression analysis using quantitative PCR (qPCR) revealed differential expression under various stress conditions such as salinity, oxidative stress, and exogenous MG stress in a tissue-specific manner. Further, in vivo functional characterization indicated that overexpression of the putative PdGLX1 genes in E. coli enhanced their growth and MG detoxification ability. The putative PdGLX1 genes were also able to complement the loss-of-function MG hypersensitive GLO1 (YML004C) yeast mutants and promote growth by enhancing MG detoxification and reducing the accumulation of reactive oxygen species (ROS) under stress conditions as indicated by flow cytometry. These findings denote the potential importance of PdGLX1 genes in MG detoxification under stress conditions in the date palm.


Assuntos
Lactoilglutationa Liase/metabolismo , Phoeniceae/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação da Expressão Gênica de Plantas , Lactoilglutationa Liase/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Phoeniceae/genética , Proteínas de Plantas/genética
20.
Biomed Pharmacother ; 131: 110663, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32858501

RESUMO

The glyoxalase system is a ubiquitous enzymatic network which plays important roles in biological life. It consists of glyoxalase 1 (GLO1), glyoxalase 2 (GLO2), and reduced glutathione (GSH), which perform an essential metabolic function in cells by detoxifying methylglyoxal (MG) and other endogenous harmful metabolites into non-toxic d-lactate. MG and MG-derived advanced glycation endproducts (AGEs) are associated with various diseases, such as diabetes, cardiovascular disease, neurodegenerative disorders and cancer, and GLO1 is a key rate-limiting enzyme in the anti-glycation defense. The abnormal activity and expression of GLO1 in various diseases make this enzyme a promising target for drug design and development. This review focuses on the regulatory mechanism of GLO1 in diverse pathogenic conditions with a thorough discussion of GLO1 regulators since their discovery, including GLO1 activators and inhibitors. The different classes, chemical structure and structure-activity relationship are embraced. Moreover, assays for the discovery of small molecule regulators of the glyoxalase system are also introduced in this article. Compared with spectrophotometer-based assay, microplate-based assay is a more simple, rapid and quantitative high-throughput method. This review will be useful to design novel and potent GLO1 regulators and hopefully provide a convenient reference for researchers.


Assuntos
Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Lactoilglutationa Liase/metabolismo , Aldeído Pirúvico/metabolismo , Animais , Produtos Biológicos/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Glicosilação/efeitos dos fármacos , Humanos , Lactoilglutationa Liase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Aldeído Pirúvico/antagonistas & inibidores
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