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1.
Methods ; 225: 100-105, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565390

RESUMO

The development of reliable probe technology for the detection of bisulfite (HSO3-) in situ in food and biological samples is contributing significantly to food quality and safety assurance as well as community health. In this work, a responsive probe, EHDI, is developed for ratiometric fluorescence detection of HSO3- in aqueous solution, meat samples, and living cells. The probe is designed based on the HSO3- triggered 1,4-addition of electron deficit C = C bond of EHDI. As a result of this specific 1,4-addition, the π-conjugation system was destructed, resulting in blue shifts of the emission from 687 to 440 nm and absorption from 577 to 355 nm. The probe has good water solubility, high sensitivity and selectivity, allowing it to be used for imaging of HSO3- internalization and production endogenously. The capability of probe EHDI for HSO3- was then validated by traditional HPLC technology, enabling accurately detect HSO3- in beef samples. The successful development of this probe thus offers a new tool for investigating HSO3- in situ in food and biological conditions.


Assuntos
Corantes Fluorescentes , Carne , Sulfitos , Sulfitos/análise , Sulfitos/química , Corantes Fluorescentes/química , Animais , Humanos , Carne/análise , Espectrometria de Fluorescência/métodos , Bovinos , Carne Vermelha/análise
2.
Biotechnol Bioeng ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822747

RESUMO

D-amino acid oxidase (DAAO)-catalyzed selective oxidative deamination is a very promising process for synthesizing l-amino acids including l-phosphinothricin ( l-PPT, a high-efficiency and broad-spectrum herbicide). However, the wild-type DAAO's low activity toward unnatural substrates like d-phosphinothricin ( d-PPT) hampers its application. Herein, a DAAO from Caenorhabditis elegans (CeDAAO) was screened and engineered to improve the catalytic potential on d-PPT. First, we designed a novel growth selection system, taking into account the intricate relationship between the growth of Escherichia coli (E. coli) and the catalytic mechanism of DAAO. The developed system was used for high-throughput screening of gene libraries, resulting in the discovery of a variant (M6) with significantly increased catalytic activity against d-PPT. The variant displays different catalytic properties on substrates with varying hydrophobicity and hydrophilicity. Analysis using Alphafold2 modeling and molecular dynamic simulations showed that the reason for the enhanced activity was the substrate-binding pocket with enlarged size and suitable charge distribution. Further QM/MM calculations revealed that the crucial factor for enhancing activity lies in reducing the initial energy barrier of the reductive half reaction. Finally, a comprehensive binding-model index to predict the enhanced activity of DAAO toward d-PPT, and an enzymatic deracemization approach was developed, enabling the efficient synthesis of l-PPT with remarkable efficiency.

3.
Opt Express ; 30(12): 20847-20858, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224820

RESUMO

The special band structure of three-dimensional Dirac semimetal (3D DSM) makes it show strong nonlinear optical characteristics in the terahertz region, which provides a new way to develop terahertz nonlinear devices with low threshold. In this paper, we theoretically study the optical bistability (OB) of transmitted light in a multilayer structure with 3D DSM embedded in two one-dimensional photonic crystals (1D PhC). The topological edge state (TES) excited by the 1D PhC heterostructure significantly enhances the local electric field near the nonlinear 3D DSM, which provides a positive condition for the realization of low threshold OB. Through parameter optimization, we obtain a threshold electric field with an incident electric field of 106 V/m levels. Furthermore, the influences of the Fermi energy and thickness of 3D DSM and the angle of the incident light on the hysteretic behavior as well as the threshold of OB are clarified. 3D DSM-based optical devices with intrinsic OB provide a building block for future integrated optical and all-optical networks.

4.
Acta Radiol ; 63(4): 467-473, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33641450

RESUMO

BACKGROUND: Dermatomyositis (DM) and muscular dystrophy are clinically difficult to differentiate. PURPOSE: To confirm the feasibility and assess the accuracy of conventional magnetic resonance imaging (MRI), T2 map, diffusion tensor imaging (DTI), and diffusion kurtosis imaging (DKI) in the differentiation of DM from muscular dystrophy. MATERIAL AND METHODS: Forty-two patients with DM proven by diagnostic criteria were enrolled in the study along with 23 patients with muscular dystrophy. Conventional MR, T2 map, DTI, and DKI images were obtained in the thigh musculature for all patients. Intramuscular T2 value, apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean diffusivity (MD), and mean kurtosis (MK) values were compared between the patients with DM and muscular dystrophy. Student's t-tests and receiver operating characteristic (ROC) curve analyses were performed for all parameters. P values < 0.05 were considered statistically significant. RESULTS: The intramuscular T2, ADC, FA, MD, and MK values within muscles were statistically significantly different between the DM and muscular dystrophy groups (P<0.01). The MK value was statistically significantly different between the groups in comparison with T2 and FA value. As a supplement to conventional MRI, the parameters of MD and MK differentiated DM and muscular dystrophy may be valuable. The optimal cut-off value of ADC and MD values (with respective AUC, sensitivity, and specificity) between DM and muscular dystrophy were 1.698 ×10-3mm2/s (0.723, 54.1%, and 78.1%) and 1.80 ×10-3mm2/s (61.9% and 70.2%), respectively. CONCLUSION: Thigh muscle ADC and MD parameters may be useful in differentiating patients with DM from those with muscular dystrophy.


Assuntos
Dermatomiosite/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Distrofias Musculares/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Appl Environ Microbiol ; 87(4)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310717

RESUMO

The traditional strategy to improve the efficiency of an entire coupled enzyme system relies on separate direction of the evolution of enzymes involved in their respective enzymatic reactions. This strategy can lead to enhanced single-enzyme catalytic efficiency but may also lead to loss of coordination among enzymes. This study aimed to overcome such shortcomings by executing a directed evolution strategy on multiple enzymes in one combined group that catalyzes the asymmetric biosynthesis of l-phosphinothricin. The genes of a glutamate dehydrogenase from Pseudomonas moorei (PmGluDH) and a glucose dehydrogenase from Exiguobacterium sibiricum (EsGDH), along with other gene parts (promoters, ribosomal binding sites (RBSs), and terminators) were simultaneously evolved. The catalytic efficiency of PmGluDH was boosted by introducing the beneficial mutation A164G (from 1.29 s-1mM-1 to 183.52 s-1mM-1), and the EsGDH expression level was improved by optimizing the linker length between the RBS and the start codon of gdh. The total turnover numbers of the bioreaction increased from 115 (GluDH WTNADPH) to 5846 (A164GNADPH coupled with low expression of EsGDH), and to 33950 (A164GNADPH coupled with high expression of EsGDH). The coupling efficiency was increased from ∼30% (GluDH_WT with low expression of GDH) to 83.3% (GluDH_A164G with high expression of GDH). In the batch production of l-phosphinothricin utilizing whole-cell catalysis, the strongest biocatalytic reaction exhibited a high space-time yield (6410 g·L-1·d-1) with strict stereoselectivity (>99% enantiomeric excess).Importance: The traditional strategy to improve multienzyme-catalyzed reaction efficiency may lead to enhanced single-enzyme catalytic efficiency but may also result in loss of coordination among enzymes. We describe a directed evolution strategy of an entire coupled enzyme system to simultaneously enhance enzyme coordination and catalytic efficiency. The simultaneous evolution strategy was applied to a multienzyme-catalyzed reaction for the asymmetric synthesis of l-phosphinothricin, which not only enhanced the catalytic efficiency of GluDH but also improved the coordination between GluDH and GDH. Since this strategy is enzyme-independent, it may be applicable to other coupled enzyme systems for chiral chemical synthesis.

6.
Med Sci Monit ; 26: e918099, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31915327

RESUMO

Fibulin-2, an extracellular matrix (ECM) protein expressed in normal epithelia, is a kind of fibulin which is associated with basement membranes (BM) and elastic ECM fibers. The role of fibulin-2 has been recognized as an oncogene. The upregulation of fibulin-2 correlates with cancer development and progression. Furthermore, the upregulation of fibulin has been detected in ovarian cancer and stomach adenocarcinoma. However, the downregulation of fibulin has been detected in different intestinal and respiratory tumor cells. Additional studies have revealed that the role of fibulin-2 in carcinogenesis is context dependent and is caused by the interaction of fibulin proteins such as cell surface receptors and other ECM proteins, including integrins and syndecans. The present study summarizes the role of fibulin in carcinogenesis and its underlying molecular mechanism.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Carcinogênese/metabolismo , Proteínas da Matriz Extracelular/fisiologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Integrinas/metabolismo , Neoplasias Ovarianas/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-38941028

RESUMO

Chronic stress has been linked to a large number of pathologies, including cancer, premature aging, and neurodegenerative diseases. The accumulation of molecular waste resulting from oxidative and heavy metal-induced stress has been ascribed as a major factor contributing to these diseases. With this in mind, we started by screening 13 small molecules to determine their antistress potential in heavy metal stress-exposed C6 glioblastoma and found that alpha-lipoic acid (ALA) (a natural antioxidant abundantly present in yeast, spinach, broccoli, and meat) was the most effective candidate. We then conducted molecular analyses to validate its mechanism of action. Dose-dependent toxicity assays of cells treated with two ALA enantiomers, R-ALA and S-ALA, showed that they are nontoxic and can be tolerated at relatively high doses. Cells exposed to heavy metal, heat, and oxidative stress showed better recovery when cultured in R-ALA-/S-ALA-supplemented medium, supported by reduction of reactive oxygen species (ROS), aggregated proteins, and mitochondrial and deoxyribonucleic acid (DNA) damage. Molecular analyses revealed protection against stress-induced apoptosis and induction of autophagy in R-ALA- and S-ALA-treated C6/U2OS cells. Consistent with these findings, normal human fibroblasts showed lifespan extension. Taken together, this study demonstrates that lipoic acid has antiaging and antistress potential and warrants further attention in laboratory and clinical studies.

8.
Front Immunol ; 14: 1265995, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022520

RESUMO

Helicobacter pylori (H. pylori) is a gram-negative bacterium exhibiting high pathogenicity. Traditional antibiotic treatments are considered ineffective as the H. pylori resistance has increased. Recently, a quadruple therapy strategy of probiotics and antibiotics to eliminate H. pylori was proposed. Probiotics play a therapeutic role as supplements in this process. The present research screened a probiotic strain (Lactobacillus crispatus FSCDJY67L3) that co-aggregates strongly with H. pylori. L. crispatus FSCDJY67L3 was demonstrated to significantly reduce H. pylori load (14C breath test) in clinical trials with H. pylori-positive patients. The Gastrointestinal Symptom Rating Scale (GSRS) score decreased, indicating improvement in the gastrointestinal discomfort of patients. Furthermore, L. crispatus FSCDJY67L3 showed no change in the structure of the intestinal flora of patients. Routine blood indices and blood biochemical indices related to liver and kidney function were also not affected in the patients. Therefore, L. crispatus FSCDJY67L3 may be used clinically as a supplement for the treatment of H. pylori. Clinical Trial Registration: https://www.chictr.org.cn/, Chinese Clinical Trial Registry (ChiCTR2100053710).


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lactobacillus crispatus , Probióticos , Humanos , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Probióticos/uso terapêutico , Método Duplo-Cego
9.
Front Microbiol ; 14: 1336345, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38348307

RESUMO

Introduction: Bacterial symbionts are prevalent in arthropods globally and play a vital role in the fitness and resistance of hosts. While several symbiont infections have been identified in the white-backed planthopper Sogatella furcifera, the impact of environmental factors on the microbiota within S. furcifera remains elusive. Methods: In this study, a total of 142 S. furcifera individuals from 18 populations were collected from 14 locations across six countries (China, Thailand, Myanmar, Cambodia, Vietnam, and Laos) analyzed with 2bRAD-M sequencing, to examine the effects of symbionts on the microbiota in the S. furcifera population, as well as the vital effects of environmental factors on the bacterial communities. Results and discussion: Based on the results, in S. furcifera, the presence of symbionts Wolbachia and Cardinium negatively influenced the abundance of other bacteria, including Enterobacter, Acinetobacter, and Lysinibacillus, while Wolbachia infection significantly decreased the diversity of the microbial community. Moreover, several environmental factors, including longitude, latitude, temperature, and precipitation, affected the abundance of symbionts and microbiota diversity in S. furcifera. These results collectively highlight the vital role of Wolbachia in S. furcifera microbiota, as well as the intricate effects of environmental factors on the bacterial communities of S. furcifera.

10.
Adv Healthc Mater ; 12(30): e2301497, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37285593

RESUMO

Sonodynamic therapy (SDT) combines ultrasound and sonosensitizers to produce toxic reactive oxygen species (ROS) for cancer cell killing. Due to the high penetration depth of ultrasound (US), SDT breaks the depth penetration barrier of conventional photodynamic therapy for the treatment of deeply seated tumors. A key point to enhance the therapeutic efficiency of SDT is the development of novel sonosensitizers with promoted ability for ROS production. Herein, ultrathin Fe-doped bismuth oxychloride nanosheets with rich oxygen vacancies and bovine serum albumin coating on surface are designed as piezoelectric sonosensitizers (BOC-Fe NSs) for enhanced SDT. The oxygen vacancies of BOC-Fe NSs provide electron trapping sites to promote the separation of e- -h+ from the band structure, which facilitates the ROS production under the ultrasonic waves. The piezoelectric BOC-Fe NSs create a built-in field and the bending bands, further accelerating the ROS generation with US irradiation. Furthermore, BOC-Fe NSs can induce ROS generation by a Fenton reaction catalyzed by Fe ion with endogenous H2 O2 in tumor tissues for chemodynamic therapy. The as-prepared BOC-Fe NSs efficiently inhibited breast cancer cell growth in both in vitro and in vivo tests. The successfully development of BOC-Fe NSs provides a new nano-sonosensitiser option for enhanced SDT for cancer therapy.


Assuntos
Neoplasias , Terapia por Ultrassom , Humanos , Oxigênio , Espécies Reativas de Oxigênio , Bioensaio , Ferro , Linhagem Celular Tumoral
11.
J Gerontol A Biol Sci Med Sci ; 78(9): 1569-1577, 2023 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-37061830

RESUMO

A variety of environmental stress stimuli have been linked to poor quality of life, tissue dysfunctions, and ailments including metabolic disorders, cognitive impairment, and accelerated aging. Oxidative, metal, and hypoxia stresses are largely associated with these phenotypes. Whereas drug development and disease therapeutics have advanced remarkably in last 3 decades, there are still limited options for stress management. Because the latter can effectively decrease the disease burden, we performed cell-based screening of antistress compounds by recruiting 3 chemical models of oxidative (paraquat), metal (cadmium nitrate), or hypoxia (cobalt chloride) stresses. The screening of 70 compounds for their ability to offer protection against oxidative, metal, and hypoxia stresses resulted in the selection of 5 compounds: Withaferin-A (Wi-A), methoxy Withaferin-A (mWi-A), Withanone (Wi-N), triethylene glycol (TEG), and Ashwagandha (Withania somnifera) leaf M2-DMSO extract (M2DM). Molecular assays revealed that whereas stress caused increase in (a) apoptosis, (b) reactive oxygen species accumulation coupled with mitochondrial depolarization, (c) DNA double-strand breaks, and (d) protein aggregation, low nontoxic doses of the selected compounds caused considerable protection. Furthermore, Wi-N, TEG, and their mixture-treated normal human fibroblasts (at young, mature, and senescent stages representing progressively increasing accumulation of stress) showed increase in proliferation. Taken together, these results suggested 3-way (oxidative, metal, and hypoxia) antistress potential of Wi-N and TEG that may be useful for management of environmental and old-age-related pathologies.


Assuntos
Qualidade de Vida , Withania , Humanos , Espécies Reativas de Oxigênio/metabolismo , Extratos Vegetais , Withania/química , Withania/metabolismo , Envelhecimento , Apoptose
12.
Toxins (Basel) ; 16(1)2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38251231

RESUMO

As one of the most common mycotoxins, deoxynivalenol (DON) can contaminate a wide range of crops and foods. Porcine circovirus 2 (PCV2) is a kind of immunosuppressive virus, which can cause porcine circovirus associated disease (PCVD) in pig farms infected with PCV2. Pigs are extremely sensitive to DON, and PCV2-infected pig farms are often contaminated with DON. Our previous studies indicated that Bacillus amyloliquefaciens B10 (B10) has the potential to alleviate the toxicity of mycotoxins. The research was aimed at investigating the effects of Bacillus amyloliquefaciens B10 on the immunosuppressive effects caused by both DON and PCV2 infection. The results indicated that the expression of the PCV2 capsid protein CAP was significantly decreased after pretreatment with Bacillus amyloliquefaciens B10. Then, the effects of the Bacillus amyloliquefaciens B10 pretreatment on the type I interferon, antiviral protein and the antiviral signal pathway cGAS-STING was further investigated. The findings displayed that the expression of the type I interferon and antiviral protein were increased, while the IL-10 were decreased after pretreatment with Bacillus amyloliquefaciens B10. The inhibition of DON on the cGAS-STING signal pathway was relieved. Furthermore, it was found that this intervention effect was produced by inhibiting autophagy. In summary, Bacillus amyloliquefaciens B10 can mitigate the immunosuppressive effects of PCV2 and DON by inhibiting the production of autophagy.


Assuntos
Bacillus amyloliquefaciens , Circovirus , Interferon Tipo I , Micotoxinas , Tricotecenos , Animais , Suínos , Produtos Agrícolas , Nucleotidiltransferases , Antivirais
13.
Biosensors (Basel) ; 12(11)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36354456

RESUMO

Photoacoustic imaging (PAI), an emerging biomedical imaging technology, capitalizes on a wide range of endogenous chromophores and exogenous contrast agents to offer detailed information related to the functional and molecular content of diseased biological tissues. Compared with traditional imaging technologies, PAI offers outstanding advantages, such as a higher spatial resolution, deeper penetrability in biological tissues, and improved imaging contrast. Based on nanomaterials and small molecular organic dyes, a huge number of contrast agents have recently been developed as PAI probes for disease diagnosis and treatment. Herein, we report the recent advances in the development of nanomaterials and organic dye-based PAI probes. The current challenges in the field and future research directions for the designing and fabrication of PAI probes are proposed.


Assuntos
Nanoestruturas , Técnicas Fotoacústicas , Técnicas Fotoacústicas/métodos , Medicina de Precisão , Meios de Contraste , Imagem Óptica/métodos
14.
J Biomol Struct Dyn ; 40(1): 1-13, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32469279

RESUMO

Coronavirus disease 2019 (COVID-19) initiated in December 2019 in Wuhan, China and became pandemic causing high fatality and disrupted normal life calling world almost to a halt. Causative agent is a novel coronavirus called Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2/2019-nCoV). While new line of drug/vaccine development has been initiated world-wide, in the current scenario of high infected numbers, severity of the disease and high morbidity, repurposing of the existing drugs is heavily explored. Here, we used a homology-based structural model of transmembrane protease serine 2 (TMPRSS2), a cell surface receptor, required for entry of virus to the target host cell. Using the strengths of molecular docking and molecular dynamics simulations, we examined the binding potential of Withaferin-A (Wi-A), Withanone (Wi-N) and caffeic acid phenethyl ester to TPMRSS2 in comparison to its known inhibitor, Camostat mesylate. We found that both Wi-A and Wi-N could bind and stably interact at the catalytic site of TMPRSS2. Wi-N showed stronger interactions with TMPRSS2 catalytic residues than Wi-A and was also able to induce changes in its allosteric site. Furthermore, we investigated the effect of Wi-N on TMPRSS2 expression in MCF7 cells and found remarkable downregulation of TMPRSS2 mRNA in treated cells predicting dual action of Wi-N to block SARS-CoV-2 entry into the host cells. Since the natural compounds are easily available/affordable, they may even offer a timely therapeutic/preventive value for the management of SARS-CoV-2 pandemic. We also report that Wi-A/Wi-N content varies in different parts of Ashwagandha and warrants careful attention for their use.Communicated by Ramaswamy H. Sarma.


Assuntos
SARS-CoV-2 , Inibidores de Serina Proteinase/farmacologia , Internalização do Vírus/efeitos dos fármacos , Vitanolídeos/farmacologia , Sítios de Ligação , COVID-19 , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Serina , Serina Endopeptidases/genética , Desenvolvimento de Vacinas
15.
Front Cell Dev Biol ; 10: 918970, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172283

RESUMO

Mortalin, a heat shock family protein enriched in cancer cells, is known to inactivate tumor suppressor protein p53. Abrogation of mortalin-p53 interaction and reactivation of p53 has been shown to trigger growth arrest/apoptosis in cancer cells and hence, suggested to be useful in cancer therapy. In this premise, we earlier screened a chemical library to identify potential disruptors of mortalin-p53 interaction, and reported two novel synthetic small molecules (5-[1-(4-methoxyphenyl) (1,2,3,4-tetraazol-5-yl)]-4-phenylpyrimidine-2-ylamine) and (4-[(1E)-2-(2-phenylindol-3-yl)-1-azavinyl]-1,2,4-triazole) called Mortaparib and MortaparibPlus, respectively. These compounds were shown to possess anticancer activity that was mediated through targeting mortalin and PARP1 proteins, essential for cancer cell survival and proliferation. Here, we report characterization of the third compound, {4-[(4-amino-5-thiophen-2-yl-1,2,4-triazol-3-yl)sulfanylmethyl]-N-(4-methoxyphenyl)-1,3-thiazol-2-amine}, isolated in the same screening. Extensive computational and molecular analyses suggested that the new compound has the capability to interact with mortalin, p53, and PARP1. We provide evidence that this new compound, although required in high concentration as compared to the earlier two compounds (Mortaparib and MortaparibPlus) and hence called MortaparibMild, also downregulates mortalin and PARP1 expression and functions in multiple ways impeding cancer cell proliferation and migration characteristics. MortaparibMild is a novel candidate anticancer compound that warrants further experimental and clinical attention.

16.
Curr Res Struct Biol ; 4: 320-331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36164647

RESUMO

Genetic mutations in p53 are frequently associated with many types of cancers that affect its stability and activity through multiple ways. The Ser46 residue present in the transactivation domain2 (TAD2) domain of p53 undergoes phosphorylation that blocks its degradation by MDM2 and leads to cell cycle arrest/apoptosis/necrosis upon intrinsic or extrinsic stresses. On the other hand, unphosphorylated p53 mutants escape cell arrest or death triggered by these molecular signaling axes and lead to carcinogenesis. Phosphorylation of Ser in the TAD2 domain of p53 mediates its interactions with transcription factor p62, yielding transcriptional activation of downstream pro-apoptotic genes. The p53 phosphorylation causes string-like elongated conformation that increases its binding affinity with the PH domain of p62. On the other hand, lack of phosphorylation causes helix-like motifs and low binding affinity to p62. We undertook molecular simulation analyses to investigate the potential of some natural small molecules (Withanone (Wi-N) & Withaferin-A (Wi-A) from Ashwagandha; Cucurbitacin-B (Cuc-B) from bitter Cucumber; and Caffeic acid phenethyl ester (CAPE) and Artepillin C (ARC) from honeybee propolis) to interact with p62-binding region of p53 and restore its wild-type activity. We found that Wi-N, Wi-A, and Cuc-B have the potential to restore p53-p62 interaction for phosphorylation-deficient p53 mutants. Wi-N, in particular, caused a reversal of the α-helical structure into an elongated string-like conformation similar to the wild-type p53. These data suggested the use of these natural compounds for the treatment of p53Ser46 mutant harbouring cancers. We also compared the efficiency of Wi-N, Wi-A, Cuc-B, CAPE, and ARC to abrogate Mortalin-p53 binding resulting in nuclear translocation and reactivation of p53 function and provide experimental evidence to the computational analysis. Taken together, the use of these small molecules for reactivation of p53 in cancer cells is suggested.

17.
Toxins (Basel) ; 14(12)2022 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-36548782

RESUMO

Type B trichothecenes commonly contaminate cereal grains and include five structurally related congeners: deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), fusarenon X (FX), and nivalenol (NIV). These toxins are known to have negative effects on human and animal health, particularly affecting food intake. However, the pathophysiological basis for anorexic effect is not fully clarified. The purpose of this study is to explore the potential roles of the brain-gut peptides substance P (SP) and glucagon-like peptide-17-36 amide (GLP-1) in anorexic responses induced by type B trichothecenes following both intraperitoneal (IP) and oral administration. SP and GLP-1 were elevated at 1 or 2 h and returned to basal levels at 6 h following exposure to DON and both ADONs. FX induced the production of both brain gut peptides with initial time at 1 or 2 h and duration > 6 h. Similar to FX, exposing IP to NIV caused elevations of SP and GLP-1 at 1 h and lasted more than 6 h, whereas oral exposure to NIV only increased both brain gut peptides at 2 h. The neurokinin-1 receptor (NK-1R) antagonist Emend® dose-dependently attenuated both SP- and DON-induced anorexic responses. Pretreatment with the GLP-1 receptor (GLP-1R) antagonist Exending9-39 induced a dose-dependent attenuation of both GLP-1- and DON-induced anorexic responses. To summarize, the results suggest that both SP and GLP-1 play important roles in anorexia induction by type B trichothecenes.


Assuntos
Depressores do Apetite , Tricotecenos do Tipo B , Tricotecenos , Animais , Humanos , Anorexia/induzido quimicamente , Substância P/toxicidade , Amidas/toxicidade , Peptídeo 1 Semelhante ao Glucagon/toxicidade , Tricotecenos/toxicidade , Depressores do Apetite/toxicidade
18.
Cancers (Basel) ; 14(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35159054

RESUMO

Withaferin A (Wi-A) and Caffeic Acid Phenethyl Ester (CAPE) are the bioactive ingredients of Ashwagandha (Withania somnifera) and propolis, respectively. Both of these natural compounds have been shown to possess anticancer activity. In the present study, we recruited a low dose of each of these compounds and developed a combination that exhibited remarkably potent anti-migratory and anti-angiogenic activities. Extensive molecular analyses including a cDNA array and expression analyses of the specific gene targets demonstrated that such activities are mediated through their effect on cell adhesion/tight junction proteins (Claudins, E-cadherin), inhibition of canonical Wnt/ß-catenin signaling pathways and the consequent downregulation of EMT-signaling proteins (Vimentin, MMPs, VEGF and VEGFR) that play a critical role in cancer metastasis. The data supported that this novel combination of Wi-A and CAPE (Wi-ACAPE, containing 0.5 µM of Wi-A and 10 µM of CAPE) may be recruited for the treatment of metastatic and aggressive cancers and, hence, warrant further evaluation by recruiting a variety of experimental and clinical metastatic models.

19.
Biomolecules ; 11(10)2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34680087

RESUMO

Withania somnifera (Ashwagandha) is used in Indian traditional medicine, Ayurveda, and is believed to have a variety of health-promoting effects. The molecular mechanisms and pathways underlying these effects have not yet been sufficiently explored. In this study, we investigated the effect of Ashwagandha extracts and their major withanolides (withaferin A and withanone) on muscle cell differentiation using C2C12 myoblasts. We found that withaferin A and withanone and Ashwagandha extracts possessing different ratios of these active ingredients have different effects on the differentiation of C2C12. Withanone and withanone-rich extracts caused stronger differentiation of myoblasts to myotubes, deaggregation of heat- and metal-stress-induced aggregated proteins, and activation of hypoxia and autophagy pathways. Of note, the Parkinson's disease model of Drosophila that possess a neuromuscular disorder showed improvement in their flight and climbing activity, suggesting the potential of Ashwagandha withanolides for the management of muscle repair and activity.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Extratos Vegetais/química , Vitanolídeos/farmacologia , Animais , Linhagem Celular , Humanos , Ayurveda/tendências , Camundongos , Células Musculares/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Extratos Vegetais/farmacologia , Vitanolídeos/química
20.
Anal Chim Acta ; 1174: 338709, 2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34247733

RESUMO

The important role of BV in clinical diagnostics of liver-related diseases has been established in veterinary medicine. However, the sensitivity and selectivity of the current BV assays remain relatively low compromising its wider application in clinical diagnosis. Herein, we developed a rapid and sensitive BV-detecting biosensor based on a novel far-red fluorescent protein smURFP, which produced fluorescence only through specific interaction with its cofactor BV. In our study, the binding of BV to smURFP was then systematically optimized based on the structures of the smURFP + BV complex to increase the sensitivity of our biosensor. A wide linear range from 0 µM to 25 µM was obtained in both chicken and human serum. The limit of detection (LOD) and limit of quantification (LOQ) for BV was as low as 0.4 nM and 1.5 nM in human serum, and 0.4 nM and 1.2 nM in chicken serum. To our knowledge, this is the lowest LOD that has ever been reported for a BV biosensor. Our study sheds light on the biological and clinical analysis of BV.


Assuntos
Biliverdina , Técnicas Biossensoriais , Humanos , Limite de Detecção
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