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1.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502219

RESUMO

Colorectal cancer (CRC) is the second deadliest cancer worldwide despite significant advances in both diagnosis and therapy. The high incidence of CRC and its poor prognosis, partially attributed to multi-drug resistance and antiapoptotic activity of cancer cells, arouse strong interest in the identification and development of new treatments. S-Adenosylmethionine (AdoMet), a natural compound and a nutritional supplement, is well known for its antiproliferative and proapoptotic effects as well as for its potential in overcoming drug resistance in many kinds of human tumors. Here, we report that AdoMet enhanced the antitumor activity of 5-Fluorouracil (5-FU) in HCT 116p53+/+ and in LoVo CRC cells through the inhibition of autophagy, induced by 5-FU as a cell defense mechanism to escape the drug cytotoxicity. Multiple drug resistance is mainly due to the overexpression of drug efflux pumps, such as P-glycoprotein (P-gp). We demonstrate here that AdoMet was able to revert the 5-FU-induced upregulation of P-gp expression and to decrease levels of acetylated NF-κB, the activated form of NF-κB, the major antiapoptotic factor involved in P-gp-related chemoresistance. Overall, our data show that AdoMet, was able to overcome 5-FU chemoresistance in CRC cells by targeting multiple pathways such as autophagy, P-gp expression, and NF-κB signaling activation and provided important implications for the development of new adjuvant therapies to improve CRC treatment and patient outcomes.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , NF-kappa B/metabolismo , S-Adenosilmetionina/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , NF-kappa B/genética , Células Tumorais Cultivadas
2.
Biochemistry ; 60(10): 791-801, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33656855

RESUMO

S-Adenosyl-l-methionine (AdoMet) is synthesized by the MAT2A isozyme of methionine adenosyltransferase in most human tissues and in cancers. Its contribution to epigenetic control has made it a target for anticancer intervention. A recent kinetic isotope effect analysis of MAT2A demonstrated a loose nucleophilic transition state. Here we show that MAT2A has a sequential mechanism with a rate-limiting step of formation of AdoMet, followed by rapid hydrolysis of the ß-γ bond of triphosphate, and rapid release of phosphate and pyrophosphate. MAT2A catalyzes the slow hydrolysis of both ATP and triphosphate in the absence of other reactants. Positional isotope exchange occurs with 18O as the 5'-oxygen of ATP. Loss of the triphosphate is sufficiently reversible to permit rotation and recombination of the α-phosphoryl group of ATP. Adenosine (α-ß or ß-γ)-imido triphosphates are slow substrates, and the respective imido triphosphates are inhibitors. The hydrolytically stable (α-ß, ß-γ)-diimido triphosphate (PNPNP) is a nanomolar inhibitor. The MAT2A protein structure is highly stabilized against denaturation by binding of PNPNP. A crystal structure of MAT2A with 5'-methylthioadenosine and PNPNP shows the ligands arranged appropriately in the ATP binding site. Two magnesium ions chelate the α- and γ-phosphoryl groups of PNPNP. The ß-phosphoryl oxygen is in contact with an essential potassium ion. Imidophosphate derivatives provide contact models for the design of catalytic site ligands for MAT2A.


Assuntos
Trifosfato de Adenosina/metabolismo , Difosfatos/metabolismo , Inibidores Enzimáticos/farmacologia , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/metabolismo , Polifosfatos/metabolismo , S-Adenosilmetionina/farmacologia , Sítios de Ligação , Humanos , Hidrólise , Cinética , Conformação Proteica
3.
Biosci Biotechnol Biochem ; 85(2): 351-358, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33604638

RESUMO

Methionine is a canonical amino acid. The protein MetX is a homoserine O-acyltransferase utilized in the methionine biosynthetic pathway. The metW gene is found adjacent to the metX gene in some bacteria, but its functions are unclear. In this study, I focused on the function of MetW and MetX from Pseudomonas aeruginosa (PaMetW and PaMetX). I demonstrated that PaMetW interacted with and activated the homoserine O-succinyltransferase (HST) activity of PaMetX. Furthermore, I elucidated that the HST activity of PaMetX in complex with PaMetW was inhibited by the addition of S-adenosyl-l-homocysteine (SAH), although PaMetX alone showed no feedback inhibition. Since PaMetW possesses a glycine-rich sequence annotated as a SAM/SAH binding site, I also investigated the relationship between this glycine-rich sequence and the inhibition caused by SAH. I revealed that alanine mutation of PaMetW Gly24 reduced the inhibitory effect of SAH. These results suggest that MetW is a regulatory protein of MetX.


Assuntos
Acetiltransferases/metabolismo , Pseudomonas aeruginosa/enzimologia , Acetiltransferases/antagonistas & inibidores , Acetiltransferases/química , Sequência de Aminoácidos , Sítios de Ligação , Metionina/metabolismo , S-Adenosilmetionina/farmacologia
4.
Int J Mol Sci ; 22(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374288

RESUMO

PURPOSE: In order to study novel therapeutic approaches taking advantage of natural compounds showing anticancer and anti-proliferative effects, we focused our interest on S-adenosyl-l-methionine, a naturally occurring sulfur-containing nucleoside synthesized from adenosine triphosphate and methionine by methionine adenosyltransferase, and its potential in overcoming drug resistance in colon cancer cells devoid of p53. RESULTS: In the present study, we demonstrated that S-adenosyl-l-methionine overcomes uL3-mediated drug resistance in p53 deleted colon cancer cells. In particular, we demonstrated that S-adenosyl-l-methionine causes cell cycle arrest at the S phase; inhibits autophagy; augments reactive oxygen species; and induces apoptosis in these cancer cells. CONCLUSIONS: Results reported in this paper led us to propose S-adenosyl-l-methionine as a potential promising agent for cancer therapy by examining p53 and uL3 profiles in tumors to yield a better clinical outcomes.


Assuntos
Neoplasias do Colo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Deleção de Genes , Proteínas Ribossômicas/metabolismo , S-Adenosilmetionina/farmacologia , Proteína Supressora de Tumor p53/deficiência , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Células HCT116 , Humanos , Proteínas Ribossômicas/genética , Proteína Supressora de Tumor p53/metabolismo
5.
Aging (Albany NY) ; 12(21): 21290-21307, 2020 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-33170152

RESUMO

BACKGROUND: Studies have demonstrated that S-adenosylmethionine could effectively affect the clinical wearing-off phenomena of levodopa, an antiparkinsonian agent; however, the detailed mechanisms for this effect need to be further clarified. RESULTS: S-adenosylmethionine and levodopa had opposite effects on the protein stability of vascular endothelial growth factor-A. The analysis of tube formation and cell viability also showed the nonconforming functions of S-adenosylmethionine and levodopa on cell angiogenesis and proliferation. Meanwhile, S-adenosylmethionine could significantly abolish the increased angiogenesis and cell viability induced by levodopa. S-adenosylmethionine resulted in G1/S phase arrest, with decreased cyclin dependent kinase 4/6 and increased p16, a specific cyclin dependent kinase inhibitor. Mechanically, the different effects of levodopa and S-adenosylmethionine were dependent on the phosphorylation and activation of extracellular signal-regulated kinase. S-adenosylmethionine could be fitted into the predicted docking pocket in the crystal structure of vascular endothelial growth factor-A, enhancing its acetylation level and reducing half-life. CONCLUSIONS: These observations suggested that methyl donor S-adenosylmethionine could act as a potential agent against vascular endothelial growth factor-A-related diseases induced by levodopa treatment. METHODS: We performed in vitro cytological analyses to assess whether S-adenosylmethionine intake could influence levodopa-induced vascular endothelial growth factor-A expression in human umbilical vein endothelial cells.


Assuntos
Antiparkinsonianos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Levodopa/farmacologia , S-Adenosilmetionina/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neovascularização Fisiológica/efeitos dos fármacos
6.
PLoS One ; 15(11): e0241224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33175859

RESUMO

Prohibitin 1 (Phb1) is a pleiotropic protein with multiple functions in mammalian cells including cell cycle regulation and mitochondrial protein stabilization. It has been proposed as a potential therapeutic target for a variety of diseases including inflammatory diseases. In this study, we investigated the potential immune-modulatory functions of Phb1 and anti-inflammatory properties of S-adenosylmethionine (SAMe) using macrophages, which play a major role in the innate immune system. The results showed that expressions of Phb1 mRNA and protein were reduced in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells (p<0.05). Phb1 knockdown further ameliorated the mRNA expression of pro- and anti-inflammatory cytokines such as TNF-α, IL-1α, IL-1ß, IL-6, and IL10 in LPS-stimulated RAW 264.7 cells. SAMe significantly attenuated LPS-induced inflammatory responses such as IL-1ß, IL-10, Nos2, and NO production in the presence of siPhb1. Luciferase reporter assay was conducted to determine the mechanisms underlying the effects of Phb1 and SAMe on the immune system. The luciferase activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was significantly increased in LPS-treated RAW 264.7 cells. In addition, the luciferase reporter assay showed increased NF-κB activation in Phb1 knockdown RAW 264.7 cells (p<0.1) and SAMe treatment attenuated the NF-κB luciferase activity in Phb1 knockdown RAW 264.7 cells. Based on the results, we concluded that Phb1 possibly modulates the inflammatory response whereas SAMe has an anti-inflammatory effect on Phb1 knockdown macrophage cells. Furthermore, Phb1 expression level has potential properties of affecting on innate immune system by modulating the NF-κB signaling pathway.


Assuntos
Imunidade Inata/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Proteínas Repressoras/deficiência , S-Adenosilmetionina/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
7.
Chem Asian J ; 15(21): 3551-3557, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-32954664

RESUMO

Employing a sequentially activated probe design method, an activatable, switchable and dual-mode probe was designed. This nanoprobe, HSDPP, could be effectively activated by H2 S to form H-type aggregates with green emission; subsequently, the aggregates could bind to mtDNA to form monomers and the emIssion color switched from green to deep-red. We exploited HSDPP to image exogenous and endogenous H2 S in living cells. Of note, for the first time, this novel nanoprobe with an optimal partition coefficient value (LogP=1.269) was successfully applied for tracking the endogenous H2 S upregulation stimulated by cystathionase activator S-adenosyl-L-methionine (SAM) in mice brains. Finally, our work provides an invaluable chemical tool for probing endogenous H2 S upregulation in vitro/vivo and, importantly, affords a prospective design strategy for developing switchable chemosensors to unveil the relationship between biomolecules and DNA in mitochondria in many promising areas.


Assuntos
Encéfalo/metabolismo , Ésteres/química , Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Iodobenzoatos/química , Nanopartículas/química , Animais , Encéfalo/diagnóstico por imagem , Ésteres/síntese química , Corantes Fluorescentes/síntese química , Sulfeto de Hidrogênio/metabolismo , Iodobenzoatos/síntese química , Camundongos , Estrutura Molecular , Imagem Óptica , Tamanho da Partícula , S-Adenosilmetionina/farmacologia , Propriedades de Superfície
8.
Molecules ; 25(18)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942773

RESUMO

S-adenosylmethionine (SAMe) is an endogenous methyl donor derived from ATP and methionine that has pleiotropic functions. Most SAMe is synthetized and consumed in the liver, where it acts as the main methylating agent and in protection against the free radical toxicity. Previous studies have shown that the administration of SAMe as a supernutrient exerted many beneficial effects in various tissues, mainly in the liver. In the present study, we aimed to clarify the direct effects of SAMe on fatty acid-induced steatosis and oxidative stress in hepatic and endothelial cells. Hepatoma FaO cells and endothelial HECV cells exposed to a mixture of oleate/palmitate are reliable models for hepatic steatosis and endothelium dysfunction, respectively. Our findings indicate that SAMe was able to significantly ameliorate lipid accumulation and oxidative stress in hepatic cells, mainly through promoting mitochondrial fatty acid entry for ß-oxidation and external triglyceride release. SAMe also reverted both lipid accumulation and oxidant production (i.e., ROS and NO) in endothelial cells. In conclusion, these outcomes suggest promising beneficial applications of SAMe as a nutraceutical for metabolic disorders occurring in fatty liver and endothelium dysfunction.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , S-Adenosilmetionina/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Ácido Oleanólico/toxicidade , Ácido Palmítico/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , S-Adenosilmetionina/uso terapêutico
9.
Mol Biotechnol ; 62(11-12): 557-562, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32949367

RESUMO

The study of senescence preservative on cut flowers helps boost the commercial value of flowers. Senescence in cut flower is associated with an increase of ethylene production, and is significantly influenced by ethylene pathway. This study was conducted to investigate whether S-adenosyl-L-methionine (SAM) and aminocyclopropane-1-carboxylic acid (ACC) involved in the ethylene synthesis process are correlated with the lysosome. The alterations of lysosome which was treated with the ethylene precursors ACC and SAM in HeLa cell using the confocal laser scanning microscope were investigated. According to the experimental results, the activity of lysosomes increased concentration dependently by ACC treatment, however, no change was observed by SAM treatment. In addition, Liquid chromatography-mass spectrometry (LC/MS) analysis was performed to confirm the effect of lysosomal enzyme (LE) extracted from egg white on ACC reduction, but no change was observed. On the contrary, to confirm the effect of ACC on lysosomes, lysosomes were extracted from HeLa cells treated with 5 mM ACC and confirmed by FE-SEM. The results showed that the size of lysosomes treated with ACC is larger than that of the control, which was treated with distilled water. The lysosomes in the control group were distributed in various ranges from 0 to 800 nm, but those treated with 5 mM ACC were in the range of 400 nm to 800 nm or more. Therefore, lysosomes had no effect on ACC, the precursor of ethylene, the aging hormone of cut flowers, however, ACC had effect on lysosomes.


Assuntos
Aminoácidos Cíclicos/farmacologia , Lisossomos/ultraestrutura , S-Adenosilmetionina/farmacologia , Cromatografia Líquida , Células HeLa , Humanos , Lisossomos/efeitos dos fármacos , Espectrometria de Massas , Microscopia Confocal , Tamanho da Partícula
10.
Cells ; 9(8)2020 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-32784836

RESUMO

Global DNA hypomethylation is a characteristic feature of colorectal carcinoma (CRC). The tumor inhibitory effect of S-adenosylmethionine (SAM) methyl donor has been described in certain cancers including CRC. However, the molecular impact of SAM treatment on CRC cell lines with distinct genetic features has not been evaluated comprehensively. HT-29 and SW480 cells were treated with 0.5 and 1 mmol/L SAM for 48 h followed by cell proliferation measurements, whole-genome transcriptome and methylome analyses, DNA stability assessments and exome sequencing. SAM reduced cell number and increased senescence by causing S phase arrest, besides, multiple EMT-related genes (e.g., TGFB1) were downregulated in both cell lines. Alteration in the global DNA methylation level was not observed, but certain methylation changes in gene promoters were detected. SAM-induced γ-H2AX elevation could be associated with activated DNA repair pathway showing upregulated gene expression (e.g., HUS1). Remarkable genomic stability elevation, namely, decreased micronucleus number and comet tail length was observed only in SW480 after treatment. SAM has the potential to induce senescence, DNA repair, genome stability and to reduce CRC progression. However, the different therapeutic responses of HT-29 and SW480 to SAM emphasize the importance of the molecular characterization of CRC cases prior to methyl donor supplementation.


Assuntos
Antineoplásicos/farmacologia , Carcinoma/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Metilação de DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , S-Adenosilmetionina/farmacologia , Antineoplásicos/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , S-Adenosilmetionina/administração & dosagem
11.
J Cell Biol ; 219(8)2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32609300

RESUMO

Stress granules (SGs) are evolutionarily conserved condensates of ribonucleoproteins that assemble in response to metabolic stresses. Because aberrant SG formation is associated with amyotrophic lateral sclerosis (ALS), understanding the connection between metabolic activity and SG composition can provide therapeutic insights into neurodegeneration. Here, we identify 17 metabolic enzymes recruited to yeast SGs in response to physiological growth stress. Furthermore, the product of one of these enzymes, AdoMet, is a regulator of SG assembly and composition. Decreases in AdoMet levels increase SG formation, while chronic elevation of AdoMet produces SG remnants lacking proteins associated with the 5' end of transcripts. Interestingly, acute elevation of AdoMet blocks SG formation in yeast and motor neurons. Treatment of ALS-derived motor neurons with AdoMet also suppresses the formation of TDP-43-positive SGs, a hallmark of ALS. Together, these results argue that AdoMet is an evolutionarily conserved regulator of SG composition and assembly with therapeutic potential in neurodegeneration.


Assuntos
Esclerose Amiotrófica Lateral/metabolismo , Grânulos Citoplasmáticos/metabolismo , Metabolismo Energético , Neurônios Motores/metabolismo , S-Adenosilmetionina/metabolismo , Saccharomyces cerevisiae/metabolismo , Estresse Fisiológico , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Grânulos Citoplasmáticos/genética , Grânulos Citoplasmáticos/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HeLa , Humanos , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , S-Adenosilmetionina/farmacologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
12.
J Cell Mol Med ; 24(18): 10322-10337, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32720467

RESUMO

Abnormal DNA methylation orchestrates many of the cancer-related gene expression irregularities such as the inactivation of tumour suppressor genes through hypermethylation as well as activation of prometastatic genes through hypomethylation. The fact that DNA methylation abnormalities can be chemically reversed positions the DNA methylation machinery as an attractive target for anti-cancer drug development. However, although in vitro studies suggested that targeting concordantly hypo- and hypermethylation is of benefit in suppressing both oncogenic and prometastatic functions of breast cancer cells, this has never been tested in a therapeutic setting in vivo. In this context, we investigated the combined therapeutic effects of an approved nutraceutical agent S-adenosylmethionine (SAM) and FDA-approved hypomethylating agent decitabine using the MDA-MB-231 xenograft model of breast cancer and found a pronounced reduction in mammary tumour volume and lung metastasis compared to the animals in the control and monotherapy treatment arms. Immunohistochemical assessment of the primary breast tumours showed a significantly reduced expression of proliferation (Ki-67) and angiogenesis (CD31) markers following combination therapy as compared to the control group. Global transcriptome and methylome analyses have revealed that the combination therapy regulates genes from several key cancer-related pathways that are abnormally expressed in breast tumours. To our knowledge, this is the first preclinical study demonstrating the anti-cancer therapeutic potential of using a combination of methylating (SAM) and demethylating agent (decitabine) in vivo. Results from this study provide a molecularly founded rationale for clinically testing a combination of agents targeting the epigenome to reduce the morbidity and mortality from breast cancer.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Decitabina/uso terapêutico , S-Adenosilmetionina/uso terapêutico , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Decitabina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica , Reprodutibilidade dos Testes , S-Adenosilmetionina/farmacologia , Transcrição Genética/efeitos dos fármacos , Transcriptoma/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Biochim Biophys Acta Mol Basis Dis ; 1866(11): 165895, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32681864

RESUMO

S-adenosyl-L-methionine is an endogenous molecule with hepato-protective properties linked to redox regulation and methylation. Here, the potential therapeutic value of SAMe was tested in 17 patients with PBC, a cholestatic disease with autoimmune phenomena targeting small bile ducts. Nine patients responded to SAMe (SAMe responders) with increased serum protein S-glutathionylation. That posttranslational protein modification was associated with reduction of serum anti-mitochondrial autoantibodies (AMA-M2) titers and improvement of liver biochemistry. Clinically, SAMe responders were younger at diagnosis, had longer duration of the disease and lower level of serum S-glutathionylated proteins at entry. SAMe treatment was associated with negative correlation between protein S-glutathionylation and TNFα. Furthermore, AMA-M2 titers correlated positively with INFγ and FGF-19 while negatively with TGFß. Additionally, cirrhotic PBC livers showed reduced levels of glutathionylated proteins, glutaredoxine-1 (Grx-1) and GSH synthase (GS). The effect of SAMe was also analyzed in vitro. In human cholangiocytes overexpressing miR-506, which induces PBC-like features, SAMe increased total protein S-glutathionylation and the level of γ-glutamylcysteine ligase (GCLC), whereas reduced Grx-1 level. Moreover, SAMe protected primary human cholangiocytes against mitochondrial oxidative stress induced by tBHQ (tert-Butylhydroquinone) via raising the level of Nrf2 and HO-1. Finally, SAMe reduced apoptosis (cleaved-caspase3) and PDC-E2 (antigen responsible of the AMA-M2) induced experimentally by glycochenodeoxycholic acid (GCDC). These data suggest that SAMe may inhibit autoimmune events in patients with PBC via its antioxidant and S-glutathionylation properties. These findings provide new insights into the molecular events promoting progression of PBC and suggest potential therapeutic application of SAMe in PBC.


Assuntos
Autoimunidade/efeitos dos fármacos , Colangite/tratamento farmacológico , Colangite/fisiopatologia , S-Adenosilmetionina/farmacologia , S-Adenosilmetionina/uso terapêutico , Antioxidantes/metabolismo , Células Cultivadas , Colangite/imunologia , Colestase/tratamento farmacológico , Colestase/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Glutationa/análogos & derivados , Glutationa/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
14.
Eur J Med Chem ; 201: 112557, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32563813

RESUMO

The spreading of new viruses is known to provoke global human health threat. The current COVID-19 pandemic caused by the recently emerged coronavirus SARS-CoV-2 is one significant and unfortunate example of what the world will have to face in the future with emerging viruses in absence of appropriate treatment. The discovery of potent and specific antiviral inhibitors and/or vaccines to fight these massive outbreaks is an urgent research priority. Enzymes involved in the capping pathway of viruses and more specifically RNA N7- or 2'O-methyltransferases (MTases) are now admitted as potential targets for antiviral chemotherapy. We designed bisubstrate inhibitors by mimicking the transition state of the 2'-O-methylation of the cap RNA in order to block viral 2'-O MTases. This work resulted in the synthesis of 16 adenine dinucleosides with both adenosines connected by various nitrogen-containing linkers. Unexpectedly, all the bisubstrate compounds were barely active against 2'-O MTases of several flaviviruses or SARS-CoV but surprisingly, seven of them showed efficient and specific inhibition against SARS-CoV N7-MTase (nsp14) in the micromolar to submicromolar range. The most active nsp14 inhibitor identified is as potent as but particularly more specific than the broad-spectrum MTase inhibitor, sinefungin. Molecular docking suggests that the inhibitor binds to a pocket formed by the S-adenosyl methionine (SAM) and cap RNA binding sites, conserved among SARS-CoV nsp14. These dinucleoside SAM analogs will serve as starting points for the development of next inhibitors for SARS-CoV-2 nsp14 N7-MTase.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Exorribonucleases/antagonistas & inibidores , Metiltransferases/antagonistas & inibidores , Nucleosídeos/química , Pneumonia Viral/tratamento farmacológico , Capuzes de RNA/metabolismo , S-Adenosilmetionina/análogos & derivados , S-Adenosilmetionina/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Adenina/química , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Exorribonucleases/metabolismo , Humanos , Metilação , Metiltransferases/metabolismo , Simulação de Acoplamento Molecular , Pandemias , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Capuzes de RNA/química , Capuzes de RNA/genética , RNA Viral/genética , RNA Viral/metabolismo , SARS-CoV-2 , Proteínas não Estruturais Virais/metabolismo
15.
J Alzheimers Dis ; 76(3): 981-995, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32597804

RESUMO

BACKGROUND: Glutathione (GSH) is an important endogenous antioxidant protecting cells from oxidative injury. Cysteine (Cys), the substrate limiting the production of GSH, is mainly generated from the trans-sulfuration pathway. S-adenosylmethionine (SAM) is a critical molecule produced in the methionine cycle and can be utilized by the trans-sulfuration pathway. Reductions in GSH and SAM as well as dysfunction in the trans-sulfuration pathway have been documented in the brains of Alzheimer's disease (AD) patients. Our previous in vivo study revealed that SAM administration attenuated oxidative stress induced by amyloid-ß (Aß) through the enhancement of GSH. OBJECTIVE: To investigate the effect of Aß-induced oxidative stress on the trans-sulfuration pathway in astrocytes and neurons, respectively, and the protective effect of SAM on neurons. METHODS: APP/PS1 transgenic mice and the primary cultured astrocytes, neurons, and HT22 cells were used in the current study. RESULTS: SAM could rescue the low trans-sulfuration pathway activity induced by Aß only in astrocytes, accompanying with increasing levels of Cys and GSH. The decrease of cellular viability of neurons caused by Aß was greatly reversed when co-cultured with astrocytes with SAM intervention. Meanwhile, SAM improved cognitive performance in APP/PS1 mice. CONCLUSION: In terms of astrocyte protection from oxidative stress, SAM might be a potent antioxidant in the therapy of AD patients.


Assuntos
Peptídeos beta-Amiloides/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , S-Adenosilmetionina/farmacologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/fisiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-32589828

RESUMO

Objective: To assess the effects of the combination of SAMe (S-adenosylmethionine) 200 mg and Lactobacillus plantarum (L. plantarum) HEAL9 1 × 109 CFU for the overall symptomatology of mild-to-moderate depression. Methods: This 6-week randomized, double-blind, placebo-controlled study included subjects aged 18-60 years with mild-to-moderate depression (according to ICD-10 diagnostic criteria) recruited from September 17, 2018, to October 5, 2018. Difference between groups in change from baseline to treatment week 6 on the Zung Self-Rating Depression Scale (Z-SDS) was the primary outcome. Comparisons between groups in change from baseline to treatment week 2 of the Z-SDS and from baseline to treatment weeks 2 and 6 of other scales (related to insomnia, anxiety, irritable bowel syndrome, and health status) were also analyzed. Results: Ninety patients were randomized to SAMe plus L. plantarum HEAL9 (n = 46) or placebo (n = 44) groups. A greater reduction for the new combination compared to placebo was seen at treatment week 6 in the Z-SDS total score (P = .0165) and the core depression subdomain (P = .0247). A significant reduction in favor of the combination was shown at treatment week 2 for the Z-SDS total score (P = .0330), the cognitive and anxiety subdomains (P = .0133 and P = .0459, respectively), and the anxiety questionnaire (P = .0345). No treatment-related adverse events occurred. Conclusions: Supplementation of SAMe and L. plantarum HEAL9 in adults with subthreshold or mild-to-moderate symptoms of depression resulted in fast and clinically relevant effects after 2 weeks. The combination was safe and significantly improved symptoms of depression, anxiety, and cognitive and somatic components. The effect of this novel product is independent from the severity of the symptoms unlike traditional antidepressants available on the market that have minimal benefits for subthreshold or mild-to-moderate symptoms. Trial Registration: ClinicalTrials.gov identifier: NCT03932474.


Assuntos
Depressão/dietoterapia , Transtorno Depressivo/dietoterapia , Lactobacillus plantarum , Avaliação de Resultados em Cuidados de Saúde , Probióticos/farmacologia , S-Adenosilmetionina/farmacologia , Adolescente , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Probióticos/administração & dosagem , S-Adenosilmetionina/administração & dosagem , Índice de Gravidade de Doença , Adulto Jovem
17.
Drug Res (Stuttg) ; 70(6): 273-279, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32316058

RESUMO

BACKGROUND AND OBJECTIVES: The pathogenesis of influenza infection is associated with two general processes in the body: (a) lung damage based on virus replication; (b) overproduction of free radicals, antioxidant deficiency, and development of oxidative stress. To attack these aspects of flu pathogenesis, we explored the combined effect of the antiviral agent oseltamivir, and s-adenosyl-l-methionine (SAM) as a precursor of the endogenous antioxidant glutathione, in mice infected with influenza virus. METHODS: After inoculation of albino mice with 10 MLD50 of influenza virus A/Aichi/2/68 (H3N2), oseltamivir was applied twice a day, for five days post-infection in doses of 1.25 and 2.5 mg/kg. SAM was administered once a day for 10 days, starting 5 days before infection in doses of 50, 100 and 150 mg/kg. RESULTS: Monotherapy with SAM did not influence the markers of oxidative stress in the lung. Combination of SAM 50 mg/kg and oseltamivir 2.5 mg/kg affected best the virological parameters - viral titer, protection index, and mean survival time, as well as the biochemical markers of oxidative stress. INTERPRETATION AND CONCLUSIONS: Combining of SAM and oseltamivir in a dose of 1/4 of optimal therapeutic could be considered as a perspective therapy of influenza viral infection.


Assuntos
Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Pulmão/efeitos dos fármacos , Oseltamivir/farmacologia , S-Adenosilmetionina/farmacologia , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Humanos , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/patologia , Influenza Humana/virologia , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oseltamivir/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , S-Adenosilmetionina/uso terapêutico , Replicação Viral/efeitos dos fármacos
18.
Int J Oncol ; 56(5): 1212-1224, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32319579

RESUMO

S­Adenosyl­L­methionine (AdoMet) is the principal methyl donor in transmethylation reactions fundamental to sustaining epigenetic modifications. Over the past decade, AdoMet has been extensively investigated for its anti­proliferative, pro­apoptotic and anti­metastatic roles in several types of human cancer. Head and neck squamous cell carcinoma (HNSCC) is the sixth most common type of cancer worldwide, and is an aggressive type of cancer that is associated with a high recurrence rate, metastasis and poor treatment outcomes. The present study demonstrates, for the first time, to the best of our knowledge, that AdoMet induces cell cycle arrest and inhibits the migratory and invasive ability of two different HNSCC cell lines, oral Cal­33 and laryngeal JHU­SCC­011 cells. In both cell lines, AdoMet attenuated cell cycle progression, decreased the protein level of several cyclins and downregulated the expression of p21 cell cycle inhibitor. Moreover, AdoMet was able to inhibit Cal­33 and JHU­SCC­011 cell migration in a dose­dependent manner after 24 and 48 h, respectively, and also induced a significant reduction in the cell invasive ability, as demonstrated by Matrigel invasion assay monitored by the xCELLigence RTCA system. Western blot analysis of several migration and invasion markers confirmed the inhibitory effects exerted by AdoMet on these processes and highlighted AKT, ß­catenin and small mothers against decapentaplegic (SMAD) as the main signaling pathways modulated by AdoMet. The present study also demonstrated that the combination of AdoMet and cisplatin synergistically inhibited HNSCC cell migration. Taken together, these findings demonstrate that the physiological compound, AdoMet, affects the motility and extracellular matrix invasive capability in HNSCC. Thus, AdoMet may prove to be a good candidate for future drug development against metastatic cancer.


Assuntos
Cisplatino/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclinas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , S-Adenosilmetionina/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Invasividade Neoplásica , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Fatores de Tempo
19.
Naunyn Schmiedebergs Arch Pharmacol ; 393(12): 2507-2515, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32219484

RESUMO

S-adenosylmethionine (SAM) is a naturally occurring physiologic molecule found ubiquitously in all mammalian cells and an essential compound in many metabolic pathways. It has been reported to possess many pharmacological properties including cancer-preventive and anticancer effects. However, the precise molecular mechanism involved in its anticancer effect is not yet clear. The present study is conducted to investigate the anticancer activity and the underlying mechanisms of SAM on human gallbladder cancer cells (GBC-SD and SGC-996) in vitro and in vivo. Cells were dealt with SAM and subjected to cell viability, colony formation, Hoechst staining, apoptosis, cycle arrest, western blot, and xenograft tumorigenicity assay. Experimental results showed that SAM could significantly inhibit the growth and proliferation and induce the apoptosis as well as cell cycle arrest in G0/G1 phase of GBC-SD and SGC-996 cells in a dose-dependent manner in vitro. The expression levels of p-JAK2, p-STAT3, Mcl-1, and Bcl-XL were significantly downregulated. In addition, inhibition of the JAK2/STAT3 pathway significantly enhanced the anti-apoptotic effect of SAM, suggesting the key roles of JAK2/STAT3 in the process. More importantly, our in vivo studies demonstrated that administration of SAM could significantly decrease the tumor weight and volume and immunohistochemistry analysis proved the downregulation of p-JAK2 and p-STAT3 in tumor tissues following SAM treatment, consistent with our in vitro results. In summary, our findings indicated that SAM can inhibit cell proliferation and induce apoptosis as well as cycle arrest of GBC cells by suppression of JAK2/STAT3 pathways and the dramatic effects of SAM hinting that SAM might be a useful therapeutic option for patients suffering from gallbladder cancer.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Neoplasias da Vesícula Biliar/tratamento farmacológico , Janus Quinase 2/antagonistas & inibidores , S-Adenosilmetionina/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Neoplasias da Vesícula Biliar/metabolismo , Humanos , Janus Quinase 2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , S-Adenosilmetionina/uso terapêutico , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
20.
Behav Brain Res ; 384: 112520, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32006563

RESUMO

Cerebral ischemia/reperfusion (I/R) injury is a leading cause of learning and memory dysfunction. Hydrogen sulfide (H2S) has been shown to confer neuroprotection in various neurodegenerative diseases, including cerebral I/R-induced hippocampal CA1 injury. However, the underlying mechanisms have not been completely understood. In the present study, rats were pretreated with SAM/NaHS (SAM, an H2S agonist, and NaHS, an H2S donor) only or SAM/NaHS combined with CaM (an activator of CaMKII) prior to cerebral ischemia. The Morris water maze test demonstrated that SAM/NaHS could alleviate learning and memory impairment induced by cerebral I/R injury. Cresyl violet staining was used to show the survival of hippocampal CA1 pyramidal neurons. SAM/NaHS significantly increased the number of surviving cells, whereas CaM weakened the protection induced by SAM/NaHS. The immunohistochemistry results indicated that the number of Iba1-positive microglia significantly increased after cerebral I/R. Compared with the I/R group, the number of Iba1-positive microglia in the SAM/NaHS groups significantly decreased. Co-Immunoprecipitation and immunoblotting were conducted to demonstrate that SAM/NaHS suppressed the assembly of CaMKII with the ASK1-MKK3-p38 signal module after cerebral I/R, which decreased the phosphorylation of p38. In contrast, CaM significantly inhibited the effects of SAM/NaHS. Taken together, the results suggested that SAM/NaHS could suppress cerebral I/R injury by downregulating p38 phosphorylation via decreasing the assembly of CaMKII with the ASK1-MKK3-p38 signal module.


Assuntos
Região CA1 Hipocampal/efeitos dos fármacos , Calmodulina/farmacologia , Sulfeto de Hidrogênio/metabolismo , AVC Isquêmico/metabolismo , Transtornos da Memória/metabolismo , Traumatismo por Reperfusão/metabolismo , S-Adenosilmetionina/farmacologia , Sulfetos/farmacologia , Animais , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Proteínas de Ligação ao Cálcio/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Regulação para Baixo , AVC Isquêmico/fisiopatologia , Aprendizagem/efeitos dos fármacos , MAP Quinase Quinase 3/efeitos dos fármacos , MAP Quinase Quinase 3/metabolismo , MAP Quinase Quinase Quinase 5/efeitos dos fármacos , MAP Quinase Quinase Quinase 5/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Transtornos da Memória/fisiopatologia , Proteínas dos Microfilamentos/efeitos dos fármacos , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Teste do Labirinto Aquático de Morris , Fosforilação , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Ratos , Traumatismo por Reperfusão/fisiopatologia , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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