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1.
Xenotransplantation ; 31(2): exen12855, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38602029

RESUMO

Carbohydrate-antigens widely existed on glycoproteins and glycosphingolipids of all mammalian cells play a crucial role in self-defense and immunity. Xeno-reactive antibodies included in natural human sera play a protecting role in an acute phase-rejection of xenotransplantation. In this study, we investigated the effect of an alteration of glycosylation-pattern, caused by human sialyltransferases such as hST3Gal II or hST6GalNAc IV, on human serum mediated cytotoxicity in pig kidney PK15 cells. From LDH cytotoxicity assay, cytotoxicity to human serum was significantly increased in hST3Gal II and hST6GalNAc IV-transfected PK15 cells, as compared to the control. In the hST6Gal I-carrying cells, the cytotoxicity to human serum was rather decreased. Moreover, flow cytometry analysis revealed that an alteration of pig glycosylation-pattern by hST3Gal II or hST6GalNAc IV influences on a binding of human IgM or IgG, respectively, in pig kidney cells, regardless of Gal antigen alteration. Finally, we found that hST6GalNAc IV contributed to increase of terminal disialylated tetrasaccharide structure, disialyl T antigen, as evidenced by increase of the MAL II lectin binding capacity in the hST6GalNAc IV-transfected PK15 cells, compared with control. Therefore, our results suggest that carbohydrate antigens, such as disialyl T antigen, newly synthesized by the ST3Gal II- and ST6GalNAc IV are potentially believed to be new xeno-reactive elements.


Assuntos
Sialiltransferases , Transplante Heterólogo , beta-Galactosídeo alfa-2,3-Sialiltransferase , Animais , Humanos , Antígenos Virais de Tumores , Carboidratos , Mamíferos/metabolismo , Sialiltransferases/genética , Sialiltransferases/química , Sialiltransferases/metabolismo , Suínos
2.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167019, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38211726

RESUMO

Immunotherapy is a promising therapeutic strategy for cancer. However, it shows limited efficacy against certain tumor types. The activation of innate immunity can suppress tumors by mitigating inflammatory and malignant behaviors through immune surveillance. The tumor microenvironment, which is composed of immune cells and cancer cells, plays a crucial role in determining the outcomes of immunotherapy. Relying solely on immune checkpoint inhibitors is not an optimal approach. Instead, there is a need to consider the use of a combination of immune checkpoint inhibitors with other modulators of the innate immune system to improve the tumor microenvironment. This can be achieved through methods such as immune cell antigen presentation and recognition. In this review, we delve into the significance of innate immune cells in tumor regression, as well as the role of the interaction of tumor cells with innate immune cells in evading host immune surveillance. These findings pave the way for the next chapter in the field of immunotherapy.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Sistema Imunitário , Imunidade Inata , Imunoterapia , Microambiente Tumoral
3.
Mol Immunol ; 166: 50-57, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237322

RESUMO

Mtb (Mycobacterium tuberculosis) is a pathogenic bacterium that causes tuberculosis infection (TB). Mtb-secreted proteins have recently been investigated as virulence factors, as well as therapeutic and vaccine possibilities. The early-secreted antigen target MTB48 is one of these proteins that has been explored as a cocktail antigen in the serodiagnosis of active tuberculosis. However, there exists no information about the function or control of MTB48's inflammatory activity in macrophages at the site of inflammation. As a result, the goal of this research was to figure out what processes are involved in MTB48's function. MTB48 stimulated inflammation in LPS induced macrophages at both the protein and mRNA levels, which was interesting. MTB48 aided LPS induced IB phosphorylation and NF-κB translocation. MTB48 also led to the phosphorylation of MAPK signaling protein. These findings imply that MTB48 can enhance inflammatory activity via NF-κB and MAPK signaling by upregulating COX-2, iNOS, NO and PGE2. Many tuberculosis antigens have been tested for the development of rapid serological diagnosis. The results of this study suggest that MTB48 is a very high conservative antigen and is a major factor causing inflammatory reactions, suggesting that it can help control and diagnose tuberculosis.


Assuntos
Antígenos de Bactérias , Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Humanos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Anti-Inflamatórios/farmacologia , Macrófagos/metabolismo , Células RAW 264.7 , Inflamação/metabolismo
4.
Arch Biochem Biophys ; 750: 109810, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37939867

RESUMO

Ganglioside GM3 is a simple monosialoganglioside (NeuAc-Gal-Glc-ceramide) that modulates cell adhesion, proliferation, and differentiation. Previously, we reported isolation of GM3-binding vascular endothelial growth factor receptor and transforming growth factor-ß receptor by the T7 phage display method (Chung et al., 2009; Kim et al., 2013). To further identify novel proteins interacting with GM3, we extended the T7 phage display method in this study. After T7 phage display biopanning combined with immobilized biotin-labeled 3'-sialyllactose prepared on a streptavidin-coated microplate, we isolated 100 candidate sequences from the human lung cDNA library. The most frequently detected clones from the blast analysis were the human nucleolar and coiled-body phosphoprotein 1 (NOLC1) sequences. We initially identified NOLC1 as a molecule that possibly binds to GM3 and confirmed this binding ability using the glutathione S-transferase fusion protein. Herein, we report another GM3-interacting protein, NOLC1, that can be isolated by the T7 phage display method. These results are expected to be helpful for elucidating the functional roles of ganglioside GM3 with NOLC1. When human breast cancer MCF-7 cells were examined for subcellular localization of NOLC1, immunofluorescence of NOLC1 was observed in the intracellular region. In addition, NOLC1 expression was increased in the nucleolus after treatment with the anticancer drug doxorubicin. GM3 and NOLC1 levels in the doxorubicin-treated MCF-7 cells were correlated, indicating possible associations between GM3 and NOLC1. Therefore, direct interactions between carbohydrates and cellular proteins can pave the path for new signaling phenomena in biology.


Assuntos
Bacteriófago T7 , Neoplasias da Mama , Humanos , Feminino , Bacteriófago T7/genética , Fator A de Crescimento do Endotélio Vascular , Gangliosídeo G(M3) , Células MCF-7 , Neoplasias da Mama/genética , Doxorrubicina , Proteínas Nucleares/metabolismo , Fosfoproteínas
5.
PLoS One ; 18(11): e0293321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917776

RESUMO

In this study, we have firstly elucidated that serum starvation augmented the levels of human GD3 synthase (hST8Sia I) gene and ganglioside GD3 expression as well as bone morphogenic protein-2 and osteocalcin expression during MG-63 cell differentiation using RT-PCR, qPCR, Western blot and immunofluorescence microscopy. To evaluate upregulation of hST8Sia I gene during MG-63 cell differentiation by serum starvation, promoter area of the hST8Sia I gene was functionally analyzed. Promoter analysis using luciferase reporter assay system harboring various constructs of the hST8Sia I gene proved that the cis-acting region at -1146/-646, which includes binding sites of the known transcription factors AP-1, CREB, c-Ets-1 and NF-κB, displays the highest level of promoter activity in response to serum starvation in MG-63 cells. The -731/-722 region, which contains the NF-κB binding site, was proved to be essential for expression of the hST8Sia I gene by serum starvation in MG-63 cells by site-directed mutagenesis, NF-κB inhibition, and chromatin immunoprecipitation (ChIP) assay. Knockdown of hST8Sia I using shRNA suggested that expressions of hST8Sia I and GD3 have no apparent effect on differentiation of MG-63 cells. Moreover, the transcriptional activation of hST8Sia I gene by serum starvation was strongly hindered by SB203580, a p38MAPK inhibitor in MG-63 cells. From these results, it has been suggested that transcription activity of hST8Sia I gene by serum starvation in human osteosarcoma MG-63 cells is regulated by p38MAPK/NF-κB signaling pathway.


Assuntos
Regulação Enzimológica da Expressão Gênica , NF-kappa B , Humanos , Ativação Transcricional , Regulação para Cima , NF-kappa B/metabolismo , Diferenciação Celular/genética , Expressão Gênica
6.
Glycoconj J ; 40(6): 621-630, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37921922

RESUMO

In this study we observed that human GD1c/GT1a/GQ1b synthase (hST8Sia V) is particularly expressed in human glioblastoma cells. To address the mechanism regulating human glioblastoma-specific gene expression of the hST8Sia V, after the transcription start site (TSS) was identified by the 5'-rapid amplification of cDNA end with total RNA from human glioblastoma U87MG cells, the 5'-flanking region (2.5 kb) of the hST8Sia V gene was isolated and its promoter activity was examined. By luciferase reporter assay, this 5'-flanking region revealed strong promoter activity in only U-87MG cells, but not in other tissue-derived cancer cells. 5'-deletion mutant analysis showed that the region from -1140 to -494 is crucial for transcription of the hST8Sia V gene in U87MG cells. This region contains the activator protein-1 (AP-1) binding site, the main target of the c-Jun N-terminal kinase (JNK) downstream. The AP-1 binding site at -1043/-1037 was proved to be indispensable for the hST8Sia V gene-specific expression in U87MG cells by site-directed mutagenesis. Moreover, the transcriptional activation of hST8Sia V gene in U87MG cells was strongly inhibited by a specific JNK inhibitor, SP600125. These results suggest that the hST8Sia V gene-specific expression in U87MG cells is controlled by JNK/AP-1 signaling pathway.


Assuntos
Glioblastoma , Humanos , Glioblastoma/genética , Fator de Transcrição AP-1/genética , Regiões Promotoras Genéticas/genética , Ativação Transcricional
10.
Artigo em Inglês | MEDLINE | ID: mdl-37622701

RESUMO

BACKGROUND: Pro-inflammatory cytokines secreted from activated macrophages and astrocytes are crucial mediators of inflammation for host defense. Among them, the secretion of IL-1ß, a major pro-inflammatory cytokine, is especially mediated by the activation of NLRP3 inflammasome. Pro-IL-1ß, which is produced in response to the invaded pathogens, such as LPS, is cleaved and matured in the NLRP3 inflammasome by the recognition of ATP. Excessively activated IL-1ß induces other immune cells, resulting in the up-regulation of inflammation. Therefore, regulation of NLRP3 inflammasome can be a good strategy for alleviating inflammation. OBJECTIVE: Our study aimed to examine whether 5-methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), has an anti-inflammatory effect on the NLRP3 inflammasome activation induced by LPS and ATP. METHODS: Primary bone marrow-derived macrophages (BMDMs) and astrocytes were stimulated by LPS and ATP with the treatment of 5-methylthiopentyl isothiocyanate, a sulforaphane analogue. The secretion of pro-inflammatory cytokines was measured by ELISA, and the expression level of NLRP3 inflammasome-associated proteins was detected by western blot. The association of NLRP3 inflammasome was assessed by co-immunoprecipitation, and the formation of ASC specks was evaluated by fluorescent microscope. RESULTS: 5-Methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), decreased the release of pro-inflammatory cytokines, IL-1ß, and IL-6 in the BMDMs. Berteroin notably prevented the formation of both NLRP3 inflammasome and ASC specks, which reduced the secretion of IL-1ß. Additionally, berteroin reduced the IL-1ß secretion and cleaved IL-1ß expression in the primary astrocytes. DISCUSSION AND CONCLUSION: These results indicated the anti-inflammatory effects of 5-methylthiopentyl isothiocyanate (berteroin) by regulating NLRP3 inflammasome activation, suggesting that berteroin could be the potential natural drug candidate for the regulation of inflammation.

11.
J Cell Biochem ; 124(9): 1423-1434, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37642132

RESUMO

Tuberculosis (TB) is caused by Mycobacterium tuberculosis (Mtb) and is still one of the global health burdens. The occurrence of various cases and multidrug resistance confirm that TB has not been completely conquered. For these reasons, the present research has been conducted to explore TB vaccine and drug candidate possibility using Mtb-secreted proteins. Among these proteins, MPT32 is known to have antigenicity and immunogenicity. There has not been a report on the host immune responses and regulation in macrophage cells. The present study was conducted with MPT32 in RAW 264.7 murine macrophage cells that control immune responses by sensing pathogen invasion and environmental change. We have found that MPT32 could activate lipopolysaccharide (LPS)-induced gene expression of metalloproteinase-9 (MMP-9) and inflammation in RAW 264.7 cells. After treating cells with MPT32, the increase in pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß (IL-1ß) and IL-6, was observed. In addition, activated macrophages expressed inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) to generate various inflammatory mediator molecules, such as nitric oxide (NO). The increase in iNOS and COX-2 levels, which are up-regulators of MMP-9 expression, was also confirmed. The biochemical events are involved in the downstream of activated MAPK signaling and translocation of NF-κ B transcription factor. The present results prove the immunomodulatory effect of MPT32 in the RAW 264.7 murine macrophage cells. it claims the possibility of a TB vaccination and drug candidate using MPT32, contributing to the prevention of TB.


Assuntos
Proteínas de Bactérias , Mycobacterium tuberculosis , Animais , Camundongos , Ciclo-Oxigenase 2/genética , Inflamação , Macrófagos , Metaloproteinase 9 da Matriz , NF-kappa B , Regulação para Cima , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Tuberculose/metabolismo , Tuberculose/microbiologia
12.
Int J Mol Sci ; 24(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175965

RESUMO

Currently, there are three major assaying methods used to validate in vitro whitening activity from natural products: methods using mushroom tyrosinase, human tyrosinase, and dopachrome tautomerase (or tyrosinase-related protein-2, TRP-2). Whitening agent development consists of two ways, melanin synthesis inhibition in melanocytes and downregulation of melanocyte stimulation. For melanin levels, the melanocyte cell line has been used to examine melanin synthesis with the expression levels of TRP-1 and TRP-2. The proliferation of epidermal surfaced cells and melanocytes is stimulated by cellular signaling receptors, factors, or mediators including endothelin-1, α-melanocyte-stimulating hormone, nitric oxide, histamine, paired box 3, microphthalmia-associated transcription factor, pyrimidine dimer, ceramide, stem cell factors, melanocortin-1 receptor, and cAMP. In addition, the promoter region of melanin synthetic genes including tyrosinase is upregulated by melanocyte-specific transcription factors. Thus, the inhibition of growth and melanin synthesis in gene expression levels represents a whitening research method that serves as an alternative to tyrosinase inhibition. Many researchers have recently presented the bioactivity-guided fractionation, discovery, purification, and identification of whitening agents. Melanogenesis inhibition can be obtained using three different methods: tyrosinase inhibition, copper chelation, and melanin-related protein downregulation. There are currently four different types of inhibitors characterized based on their enzyme inhibition mechanisms: competitive, uncompetitive, competitive/uncompetitive mixed-type, and noncompetitive inhibitors. Reversible inhibitor types act as suicide substrates, where traditional inhibitors are classified as inactivators and reversible inhibitors based on the molecule-recognizing properties of the enzyme. In a minor role, transcription factors can also be downregulated by inhibitors. Currently, the active site copper iron-binding inhibitors such as kojic acid and chalcone exhibit tyrosinase inhibitory activity. Because the tyrosinase catalysis site structure is important for the mechanism determination of tyrosinase inhibitors, understanding the enzyme recognition and inhibitory mechanism of inhibitors is essential for the new development of tyrosinase inhibitors. The present review intends to classify current natural products identified by means of enzyme kinetics and copper chelation to exhibit tyrosinase enzyme inhibition.


Assuntos
Melaninas , Monofenol Mono-Oxigenase , Humanos , Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Cobre/metabolismo , Cinética , Melanócitos/metabolismo , Fatores de Transcrição/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Inibidores Enzimáticos/farmacologia
13.
Curr Med Chem ; 30(39): 4479-4491, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36694324

RESUMO

BACKGROUND: The representative symptom of Alzheimer's Disease (AD) has mainly been mentioned to be misfolding of amyloid proteins, such as amyloid-beta (Aß) and tau protein. In addition, the neurological pathology related to neuroinflammatory signaling has recently been raised as an important feature in AD. Currently, numerous drug candidates continue to be investigated to reduce symptoms of AD, including amyloid proteins misfolding and neuroinflammation. OBJECTIVE: Our research aimed to identify the anti-AD effects of two chemical derivatives modified from cromoglicic acid, CNU 010 and CNU 011. METHODS: CNU 010 and CNU 011 derived from cromoglicic acid were synthesized. The inhibitory effects of Aß and tau were identified by thioflavin T assay. Moreover, western blots were conducted with derivates CNU 010 and CNU 011 to confirm the effects on inflammation. RESULTS: CNU 010 and CNU 011 significantly inhibited the aggregation of Aß and tau proteins. Moreover, they reduced the expression levels of mitogen-activated protein (MAP) kinase and nuclear factor kappa-light-chain-enhancer of activated B cells (NF- κB) signaling proteins, which are representative early inflammatory signaling markers. Also, the inhibitory effects on the lipopolysaccharide (LPS)-induced cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) expression referring to late inflammation were confirmed. CONCLUSION: Our results showing multiple beneficial effects of cromolyn derivatives against abnormal aggregation of amyloid proteins and neuroinflammatory signaling provide evidence that CNU 010 and CNU 011 could be further developed as potential drug candidates for AD treatment.


Assuntos
Doença de Alzheimer , Cromolina Sódica , Humanos , Cromolina Sódica/efeitos adversos , Doenças Neuroinflamatórias , Proteínas Amiloidogênicas/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , NF-kappa B/metabolismo , Inflamação/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Microglia/metabolismo
14.
Curr Med Chem ; 30(18): 2075-2112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36017851

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs), also known as metalloproteinases, are enzymes that degrade proteins and require the presence of active metal atoms. There are more than 20 types of MMPs, and they promote cell migration through the proteolytic degradation of the extracellular basement. MMPs are upregulated in cancers and inflamed regions. MMPs have three conservation regions: pro-MMP, catalysis, and hemopexin. Through these domains, MMPs cleave matrixes and cell-cell barriers. Consequently, MMPs cleave the whole extracellular matrix (ECM). In other words, they decompose most of the components related to the ECM, in their roles as key enzymes in cellular and pathophysiological events in the body. INTRODUCTION: Zn2+-containing endo-type peptidases directly degrade and remodel the ECM region in the progression of various diseases. MMPs are frequently found in abnormal disease status of inflammatory responses, periodontal lesion, inflammatory pulmonary lesion, arteriosclerotic smooth muscles, arthritis, and tumor metastasis and invasion. They are also known to participate in aging processes-such as wrinkle formation-by destroying collagen in the dermis. In particular, the onset of diseases via the MMP-dependent inflammatory response is caused by the breakdown of proteins in the ECM and the basement membranous region, which are the supporting structures of cells. METHODS: This review describes the developments in the research examining the general and selective inhibitors for MMP associated with various human diseases over the past 20 years in terms of structure remodeling, substrate-recognizing specificities, and pharmacological applicability. RESULTS: Among two similar types of MMPs, MMP-2 is known as gelatinase-A with a 72 kDa, while MMP-9 is termed gelatinase-B with a 92 kDa. Both of these play a key role in this action. Therefore, both enzymatic expression levels coincide during the onset and progression of diseases. Endogenous tissue inhibitors of matrix metalloproteinases (TIMPs) are highly specific for each MMP inhibitor type. The intrinsic factors regulate various MMP types by inhibiting the onset of various diseases mediated by MMP-dependent or independent inflammatory responses. The MMP- 9 and MMP-2 enzyme activity related to the prognosis of diseases associated with the inflammatory response are selectively inhibited by TIMP1 and TIMP2, respectively. The major pathogenesis of MMP-mediated diseases is related to the proliferation of inflammatory cells in various human tissues, which indicates their potential to diagnose or treat these diseases. The discovery of a substance that inhibits MMPs would be very important for preventing and treating various MMP-dependent diseases. CONCLUSION: Considerable research has examined MMP inhibitors, but most of these have been synthetic compounds. Research using natural products as MMP inhibitors has only recently become a subject of interest. This review intends to discuss recent research trends regarding the physiological properties, functions, and therapeutic agents related to MMPs.


Assuntos
Inibidores de Metaloproteinases de Matriz , Neoplasias , Humanos , Inibidores de Metaloproteinases de Matriz/farmacologia , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Metaloproteinase 2 da Matriz/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Matriz Extracelular/metabolismo , Gelatinases/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo
15.
Int J Mol Sci ; 23(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36555470

RESUMO

Cellular metabolism governs the signaling that supports physiological mechanisms and homeostasis in an individual, including neuronal transmission, wound healing, and circadian clock manipulation. Various factors have been linked to abnormal metabolic reprogramming, including gene mutations, epigenetic modifications, altered protein epitopes, and their involvement in the development of disease, including cancer. The presence of multiple distinct hallmarks and the resulting cellular reprogramming process have gradually revealed that these metabolism-related molecules may be able to be used to track or prevent the progression of cancer. Consequently, translational medicines have been developed using metabolic substrates, precursors, and other products depending on their biochemical mechanism of action. It is important to note that these metabolic analogs can also be used for imaging and therapeutic purposes in addition to competing for metabolic functions. In particular, due to their isotopic labeling, these compounds may also be used to localize and visualize tumor cells after uptake. In this review, the current development status, applicability, and limitations of compounds targeting metabolic reprogramming are described, as well as the imaging platforms that are most suitable for each compound and the types of cancer to which they are most appropriate.


Assuntos
Relógios Circadianos , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Relógios Circadianos/genética , Transdução de Sinais/genética , Reprogramação Celular , Homeostase
17.
Front Mol Biosci ; 9: 985648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172045

RESUMO

Human N-acetylgalactosamine-α2,6-sialyltransferase (hST6GalNAc I) is the major enzyme involved in the biosynthesis of sialyl-Tn antigen (sTn), which is known to be expressed in more than 80% of human carcinomas and correlated with poor prognosis in cancer patients. Athough high expression of hST6GalNAc I is associated with augmented proliferation, migration and invasion in various cancer cells, transcriptional mechanism regulating hST6GalNAc I gene expression remains largely unknown. In this study, we found that hST6GalNAc I gene expression was markedly augmented by curcumin in HCT116 human colon carcinoma cells. To understand the molecular mechanism for the upregulation of hST6GalNAc I gene expression by curcumin in HCT116 cells, we first determined the transcriptional start site of hST6GalNAc I gene by 5'-RACE and cloned the proximal hST6GalNAc I 5'-flanking region spanning about 2 kb by PCR. Functional analysis of the hST6GalNAc I 5' flanking region of hST6GalNAc I by sequential 5'-deletion, transient transfection of reporter gene constructs and luciferase reporter assays showed that -378/-136 region is essential for maximal activation of transcription in response to curcumin in HCT 116 cells. This region includes putative binding sites for transcription factors c-Ets-1, NF-1, GATA-1, ER-α, YY1, and GR-α. ChIP analysis and site-directed mutagenesis demonstrated that estrogen receptor α (ER-α) binding site (nucleotides -248/-238) in this region is crucial for hST6GalNAc I gene transcription in response to curcumin stimulation in HCT116 cells. The transcription activity of hST6GalNAc I gene induced by curcumin in HCT116 cells was strongly inhibited by PKC inhibitor (Gö6983) and ERK inhibitor (U0126). These results suggest that curcumin-induced hST6GalNAc I gene expression in HCT116 cells is modulated through PKC/ERKs signal pathway.

18.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077327

RESUMO

In this study, we tried to develop a FimH inhibitor that inhibits adhesion of enterohemorrhagic Escherichia coli (EHEC) on the epithelium of human intestine during the initial stage of infections. Using a T7 phage display method with a reference strain, EHEC EDL933, FimH was selected as an adherent lectin to GM1a and Gb3 glycans. In order to detect the ligand binding domain (LBD) of FimH, we used a docking simulation and found three binding site sequences of FimH, i.e., P1, P2, and P3. Among Gb3 mimic peptides, P2 was found to have the strongest binding strength. Moreover, in vitro treatment with peptide P2 inhibited binding activity in a concentration-dependent manner. Furthermore, we conducted confirmation experiments through several strains isolated from patients in Korea, EHEC NCCP15736, NCCP15737, and NCCP15739. In addition, we analyzed the evolutionary characteristics of the predicted FimH lectin-like adhesins to construct a lectin-glycan interaction (LGI). We selected 70 recently differentiated strains from the phylogenetic tree of 2240 strains with Shiga toxin in their genome. We can infer EHEC strains dynamically evolved but FimH was conserved during the evolution time according to the phylogenetic tree. Furthermore, FimH could be a reliable candidate of drug target in terms of evolution. We examined how pathogen lectins interact with host glycans early in infection in EDL933 as well as several field strains and confirmed that glycan-like peptides worked as an initial infection inhibitor.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Escherichia coli O157 , Proteínas de Escherichia coli , Adesinas de Escherichia coli/metabolismo , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli O157/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Humanos , Lectinas/metabolismo , Filogenia , Polissacarídeos/metabolismo
19.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077431

RESUMO

Aerobic glycolysis is an emerging hallmark of many human cancers, as cancer cells are defined as a "metabolically abnormal system". Carbohydrates are metabolically reprogrammed by its metabolizing and catabolizing enzymes in such abnormal cancer cells. Normal cells acquire their energy from oxidative phosphorylation, while cancer cells acquire their energy from oxidative glycolysis, known as the "Warburg effect". Energy-metabolic differences are easily found in the growth, invasion, immune escape and anti-tumor drug resistance of cancer cells. The glycolysis pathway is carried out in multiple enzymatic steps and yields two pyruvate molecules from one glucose (Glc) molecule by orchestral reaction of enzymes. Uncontrolled glycolysis or abnormally activated glycolysis is easily observed in the metabolism of cancer cells with enhanced levels of glycolytic proteins and enzymatic activities. In the "Warburg effect", tumor cells utilize energy supplied from lactic acid-based fermentative glycolysis operated by glycolysis-specific enzymes of hexokinase (HK), keto-HK-A, Glc-6-phosphate isomerase, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase, phosphofructokinase (PFK), phosphor-Glc isomerase (PGI), fructose-bisphosphate aldolase, phosphoglycerate (PG) kinase (PGK)1, triose phosphate isomerase, PG mutase (PGAM), glyceraldehyde-3-phosphate dehydrogenase, enolase, pyruvate kinase isozyme type M2 (PKM2), pyruvate dehydrogenase (PDH), PDH kinase and lactate dehydrogenase. They are related to glycolytic flux. The key enzymes involved in glycolysis are directly linked to oncogenesis and drug resistance. Among the metabolic enzymes, PKM2, PGK1, HK, keto-HK-A and nucleoside diphosphate kinase also have protein kinase activities. Because glycolysis-generated energy is not enough, the cancer cell-favored glycolysis to produce low ATP level seems to be non-efficient for cancer growth and self-protection. Thus, the Warburg effect is still an attractive phenomenon to understand the metabolic glycolysis favored in cancer. If the basic properties of the Warburg effect, including genetic mutations and signaling shifts are considered, anti-cancer therapeutic targets can be raised. Specific therapeutics targeting metabolic enzymes in aerobic glycolysis and hypoxic microenvironments have been developed to kill tumor cells. The present review deals with the tumor-specific Warburg effect with the revisited viewpoint of recent progress.


Assuntos
Glicólise , Neoplasias , Hexoquinase/metabolismo , Humanos , Neoplasias/metabolismo , Fosfofrutoquinase-1/metabolismo , Fosfoglicerato Quinase/metabolismo , Fosfoglicerato Mutase/metabolismo , Piruvatos , Microambiente Tumoral
20.
Artigo em Inglês | MEDLINE | ID: mdl-35692582

RESUMO

Oat (Avena sativa L.) is one of the most widely consumed cereal grains worldwide and is considered as an important cereal crop with high nutritional value and potential health benefits. With different bacterial strains, fermented oat extracts were examined for the antioxidant and antiaging effects on the skin after optimization of extraction conditions. Fermented oats contained high avenanthramides, and its function was investigated on matrix metalloproteinase-1 and collagen expression with human dermal fibroblast cells. After fractionation, butanol layers showed the highest avenanthramides contents. Therefore, the microbial fermentation of oats enhances the quality and content of functional ingredients of oats, which provide natural dietary supplements, antioxidants, and antiaging agents.

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