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1.
Mol Reprod Dev ; 91(3): e23737, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38450862

RESUMO

Extracellular vesicles (EVs) play an important role in the development and function of mammalian ovarian follicles. However, the mechanisms by which they are taken up by the follicular granulosa cells remain unclear. In addition, while oocytes play a pivotal role in follicular development, the possible interactions between oocyte-derived paracrine factors (ODPFs) and EV signals are unknown. Therefore, this study aimed to elucidate the mechanism of EV uptake and the effects of ODPFs on EV uptake by follicular somatic mural granulosa cells in mice. Fluorescence-labeled transferrin (TRF) and cholera toxin B (CTB), substrates for clathrin- and caveolae-mediated endocytosis, respectively, were taken up by mural granulosa cells in vitro. Their uptake was inhibited by Pitstop 2 and genistein, inhibitors of clathrin and caveolae pathways, respectively. Mural granulosa cells took up EVs, and this uptake was suppressed by Pitstop 2 and genistein. Moreover, ODPFs promoted the uptake of EVs and CTB, but not TRF, by mural granulosa cells. These results suggest that mural granulosa cells take up EVs through both clathrin- and caveolae-mediated endocytosis and that oocytes may promote caveolae-mediated endocytosis to facilitate the uptake of EVs.


Assuntos
Vesículas Extracelulares , Genisteína , Sulfonamidas , Tiazolidinas , Feminino , Animais , Camundongos , Genisteína/farmacologia , Células da Granulosa , Clatrina , Mamíferos
2.
Biosystems ; 237: 105177, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38458346

RESUMO

The escalating global incidence of cancer poses significant health challenges, underscoring the need for innovative and more efficacious treatments. Cancer immunotherapy, a promising approach leveraging the body's immune system against cancer, emerges as a compelling solution. Consequently, the identification and characterization of tumor T-cell antigens (TTCAs) have become pivotal for exploration. In this manuscript, we introduce TTCA-IF, an integrative machine learning-based framework designed for TTCAs identification. TTCA-IF employs ten feature encoding types in conjunction with five conventional machine learning classifiers. To establish a robust foundation, these classifiers are trained, resulting in the creation of 150 baseline models. The outputs from these baseline models are then fed back into the five classifiers, generating their respective meta-models. Through an ensemble approach, the five meta-models are seamlessly integrated to yield the final predictive model, the TTCA-IF model. Our proposed model, TTCA-IF, surpasses both baseline models and existing predictors in performance. In a comparative analysis involving nine novel peptide sequences, TTCA-IF demonstrated exceptional accuracy by correctly identifying 8 out of 9 peptides as TTCAs. As a tool for screening and pinpointing potential TTCAs, we anticipate TTCA-IF to be invaluable in advancing cancer immunotherapy.


Assuntos
Aprendizado de Máquina , Neoplasias , Humanos , Tiazolidinas , Linfócitos T , Neoplasias/terapia , Neoplasias/diagnóstico
3.
PLoS One ; 19(3): e0290672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38483897

RESUMO

Viral and cellular particles too large to freely diffuse have two different types of mobility in the eukaryotic cell cytoplasm: directed motion mediated by motor proteins moving along cytoskeletal elements with the particle as its load, and motion in random directions mediated by motor proteins interconnecting cytoskeletal elements. The latter motion is referred to as "active diffusion." Mechanisms of directed motion have been extensively studied compared to mechanisms of active diffusion, despite the observation that active diffusion is more common for many viral and cellular particles. Our previous research showed that active diffusion of vesicular stomatitis virus (VSV) ribonucleoproteins (RNPs) in the cytoplasm consists of hopping between traps and that actin filaments and myosin II motors are components of the hop-trap mechanism. This raises the question whether similar mechanisms mediate random motion of larger particles with different physical and biological properties. Live-cell fluorescence imaging and a variational Bayesian analysis used in pattern recognition and machine learning were used to determine the molecular mechanisms of random motion of VSV inclusion bodies and cellular early endosomes. VSV inclusion bodies are membraneless cellular compartments that are the major sites of viral RNA synthesis, and early endosomes are representative of cellular membrane-bound organelles. Like VSV RNPs, inclusion bodies and early endosomes moved from one trapped state to another, but the distance between states was inconsistent with hopping between traps, indicating that the apparent state-to-state movement is mediated by trap movement. Like VSV RNPs, treatment with the actin filament depolymerizing inhibitor latrunculin A increased VSV inclusion body mobility by increasing the size of the traps. In contrast neither treatment with latrunculin A nor depolymerization of microtubules by nocodazole treatment affected the size of traps that confine early endosome mobility, indicating that intermediate filaments are likely major trap components for these cellular organelles.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Tiazolidinas , Estomatite Vesicular , Animais , Humanos , Estomatite Vesicular/metabolismo , Teorema de Bayes , Vírus da Estomatite Vesicular Indiana/genética , Vesiculovirus , Vesículas Transportadoras , Endossomos/metabolismo , Corpos de Inclusão , Mamíferos
4.
Anal Chem ; 96(13): 5125-5133, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38502245

RESUMO

Protein modification by lipid-derived electrophiles (LDEs) is associated with various signaling pathways. Among these LDEs, 4-hydroxy-2-nonenal (HNE) is the most toxic, and protein modified with HNE has been linked to various diseases, including Alzheimer's and Parkinson's. However, due to their low abundance, in-depth profiling of HNE modifications still presents challenges. This study introduces a novel strategy utilizing reversible thiazolidine chemistry to selectively capture HNE-modified proteins and a palladium-mediated cleavage reaction to release them. Thousands of HNE-modified sites in different cell lines were identified. Combined with ABPP, we discovered a set of HNE-sensitive sites that offer a new tool for studying LDE modifications in proteomes.


Assuntos
Aldeídos , Processamento de Proteína Pós-Traducional , Tiazolidinas , Aldeídos/metabolismo , Proteoma/metabolismo , Peroxidação de Lipídeos
5.
Bioorg Chem ; 146: 107307, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537337

RESUMO

In this study, two linear and corresponding cyclic heptapeptide versions of mortiamide A-lugdunin hybrids were designed and synthesized by integrating an anti-malarial peptide epitope derived from Mortiamide A, combined with four residues known for their membrane interactions. Using this synthetic strategy, the sequence of mortiamide A was partly re-engineered with an epitope sequence of lugdunin along with an amino acid replacement using all-L and D/L configurations. Importantly, the re-engineered cyclic mortiamides with all-L (3) and D/L (4) configurations exhibited promising anti-malarial activities against the P. falciparum drug-sensitive TM4/8 strain with half-maximal inhibitory concentration (IC50) values of 6.2 ± 0.5 and 4.8 ± 0.1 µM, respectively. Additionally, they exhibited anti-malarial activities against the P. falciparum multidrug-resistant V1/S strain with IC50 values of 5.0 ± 2.6 and 3.7 ± 0.7 µM, respectively. Interestingly, a linear re-engineered mortiamide with D/L configuration (2) exhibited promising anti-malarial activities, surpassing those of the re-engineered cyclic mortiamides (3 and 4), against both the P. falciparum sensitive TM4/8 and multidrug-resistant V1/S strains with IC50 values of 3.6 ± 0.5 and 2.8 ± 0.7 µM (IC50 of Mortiamide A = 7.85 ± 0.97, 5.31 ± 0.24 µM against 3D7 and Dd2 strains) without any cytotoxicity at >100 µM. The presence of D/L forms in a linear structure significantly impacted the anti-malarial activity against both the P. falciparum sensitive TM4/8 strain and the multidrug-resistant V1/S strain.


Assuntos
Antimaláricos , Malária Falciparum , Peptídeos Cíclicos , Plasmodium , Tiazolidinas , Humanos , Antimaláricos/química , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico , Epitopos
6.
Molecules ; 29(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38398573

RESUMO

A set of 5-(substituted benzylidene) thiazolidine-2,4-dione derivatives was explored to study the main structural requirement for the design of protein tyrosine phosphatase 1B (PTP1B) inhibitors. Utilizing multiple linear regression (MLR) analysis, we constructed a robust quantitative structure-activity relationship (QSAR) model to predict inhibitory activity, resulting in a noteworthy correlation coefficient (R2) of 0.942. Rigorous cross-validation using the leave-one-out (LOO) technique and statistical parameter calculations affirmed the model's reliability, with the QSAR analysis revealing 10 distinct structural patterns influencing PTP1B inhibitory activity. Compound 7e(ref) emerged as the optimal scaffold for drug design. Seven new PTP1B inhibitors were designed based on the QSAR model, followed by molecular docking studies to predict interactions and identify structural features. Pharmacokinetics properties were assessed through drug-likeness and ADMET studies. After that density functional theory (DFT) was conducted to assess the stability and reactivity of potential diabetes mellitus drug candidates. The subsequent dynamic simulation phase provided additional insights into stability and interactions dynamics of the top-ranked compound 11c. This comprehensive approach enhances our understanding of potential drug candidates for treating diabetes mellitus.


Assuntos
Diabetes Mellitus , Relação Quantitativa Estrutura-Atividade , Humanos , Simulação de Acoplamento Molecular , Tiazolidinas/farmacologia , Tiazolidinas/química , Reprodutibilidade dos Testes , Simulação de Dinâmica Molecular , Inibidores Enzimáticos/química , Diabetes Mellitus/tratamento farmacológico
7.
J Pharm Biomed Anal ; 242: 116027, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401350

RESUMO

Detecting cyanide compounds in postmortem blood samples is an important matter in forensic science because cyanide is often used as a poison for murder or suicide. However, the direct analysis of cyanide itself has practical limitations because of cyanide's volatility and short half-life at ambient temperature. Here, we focused on the relatively stable cyanide metabolites 2-aminothiazoline-4-carboxylic acid (ATCA) and 2-aminothiazoline-4-oxoaminoethanoic acid (ATOEA) as potential markers of cyanide exposure. We developed an analytical method that uses chemical derivatization of the target compounds with 4-bromoethyl-7-methoxycoumarin followed by liquid chromatography coupled with electrospray ionization-tandem mass spectrometry. The recovery rates for pretreatment and calibration curve linearities were good in the concentration range of 20-1000 ng/mL. Using our approach, we were able to detect and quantify both ATCA and ATOEA concentrations in postmortem blood samples, and in our samples the ratio of ATCA and ATOEA was in the range of 4.5-19.1. To our knowledge, this is the first time ATOEA has been successfully detected in human blood samples. In addition, we found that ATCA and ATOEA concentrations were both significantly higher in the blood of fire victims than in the blood of individuals with a non-fire-related cause of death. Also, we found that there was a significant positive correlation between ATCA concentrations and ATOEA concentrations. Together, our present data suggested that ATCA and ATOEA are both potential markers of cyanide exposure.


Assuntos
Arginina , Cianetos , Espectrometria de Massas em Tandem , Tiazóis , Tiazolidinas , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Cianetos/metabolismo
8.
Proc Natl Acad Sci U S A ; 121(10): e2316675121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38422021

RESUMO

The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel that regulates electrolyte and fluid balance in epithelial tissues. While activation of CFTR is vital to treating cystic fibrosis, selective inhibition of CFTR is a potential therapeutic strategy for secretory diarrhea and autosomal dominant polycystic kidney disease. Although several CFTR inhibitors have been developed by high-throughput screening, their modes of action remain elusive. In this study, we determined the structure of CFTR in complex with the inhibitor CFTRinh-172 to an overall resolution of 2.7 Å by cryogenic electron microscopy. We observe that CFTRinh-172 binds inside the pore near transmembrane helix 8, a critical structural element that links adenosine triphosphate hydrolysis with channel gating. Binding of CFTRinh-172 stabilizes a conformation in which the chloride selectivity filter is collapsed, and the pore is blocked from the extracellular side of the membrane. Single-molecule fluorescence resonance energy transfer experiments indicate that CFTRinh-172 inhibits channel gating without compromising nucleotide-binding domain dimerization. Together, these data reconcile previous biophysical observations and provide a molecular basis for the activity of this widely used CFTR inhibitor.


Assuntos
Trifosfato de Adenosina , Regulador de Condutância Transmembrana em Fibrose Cística , Tiazolidinas , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Dimerização , Benzoatos
9.
Bioorg Chem ; 144: 107177, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335756

RESUMO

In order to find effective α-glucosidase inhibitors, a series of thiazolidine-2,4-dione derivatives (C1 âˆ¼ 36) were synthesized and evaluated for α-glucosidase inhibitory activity. Compared to positive control acarbose (IC50 = 654.35 ± 65.81 µM), all compounds (C1 âˆ¼ 36) showed stronger α-glucosidase inhibitory activity with IC50 values of 0.52 ± 0.06 âˆ¼ 9.31 ± 0.96 µM. Among them, C23 with the best anti-α-glucosidase activity was a reversible mixed-type inhibitor. Fluorescence quenching suggested the binding process of C23 with α-glucosidase in a static process. Fluorescence quenching, CD spectra, and 3D fluorescence spectra results also implied that the binding of C23 with α-glucosidase caused the conformational change of α-glucosidase to inhibit the activity. Molecular docking displayed the binding interaction of C23 with α-glucosidase. Compound C23 (8 âˆ¼ 64 µM) showed no cytotoxicity against LO2 and 293 cells. Moreover, oral administration of C23 (50 mg/kg) could reduce blood glucose and improve glucose tolerance in mice.


Assuntos
Inibidores de Glicosídeo Hidrolases , Hipoglicemiantes , Tiazolidinedionas , Camundongos , Animais , Inibidores de Glicosídeo Hidrolases/química , Hipoglicemiantes/química , Estrutura Molecular , Relação Estrutura-Atividade , alfa-Glucosidases/metabolismo , Simulação de Acoplamento Molecular , Tiazolidinas
10.
Chembiochem ; 25(7): e202300844, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38337189

RESUMO

An organocatalytic [3+2] cycloaddition reaction between thiazolidine-containing ß-ketoester 1 and aryl azides 2 was employed to synthesize new 1,2,3-triazolyl-thiazolidine hybrids 3. In this metal-free approach, twelve compounds were isolated in yields ranging from 23 % to 96 % by using diethylamine (10 mol%) and DMSO at 75 °C for 24 hours. DNA-binding assays were conducted through absorption, emission spectroscopy and viscosimetry analysis, to evaluate the interaction capacity of the studied derivatives with nucleic acids. All the synthesized compounds were evaluated for their interactions with a specific group of compounds containing the pharmacophoric groups triazole and thiazolidine through a molecular docking speculative study, aimed at identifying the interaction profile of these compounds with DNA. The obtained results suggest that 1,2,3-triazolyl-thiazolidine hybrids could be a promising approach in the development of novel therapeutic agents targeting DNA-related processes.


Assuntos
Estrutura Molecular , Tiazolidinas/química , Simulação de Acoplamento Molecular , Reação de Cicloadição , Relação Estrutura-Atividade
11.
Inorg Chem ; 63(7): 3383-3392, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38315637

RESUMO

Clenbuterol (CLB) as an illegal feed additive may cause a great security risk to food safety. However, convenient and efficient detection means for CLB in practical application remain a formidable challenge. Herein, a stable Eu-based organic framework {[H2N(CH3)2]2[Eu2(ttca)2]·H2O}n (compound 1) (H4ttca = [1,1':2',1″-terphenyl]-4,4',4″,5'-tetracarboxylic acid) has been harvested, exhibiting excellent chemical stability and thermal stability. Luminescence investigation reveals that compound 1 can sensitively and selectively detect CLB without being affected by different components from simulated serum and urine (limit detection: 22.7 nM). Furthermore, sensor 1 can also be applicable to CLB recognition in real swine feeds, presenting excellent anti-interference performance. The good cyclicity of compound 1 endows CLB determination with many advantages: low cost, high stability, and simplicity. Importantly, in view of the indication of the luminescence color (red to blue), test membranes were fabricated and employed for convenient and fast CLB detection, providing a valuable scheme for the visual monitoring of CLB in meat products. This work enriches rare earth metal compounds and luminescence sensor portfolios and breaks the concentration record (nM) for detecting CLB compared with reported complex materials, providing an effective monitoring platform for CLB visually.


Assuntos
Clembuterol , Animais , Suínos , Luminescência , Tiazolidinas
12.
Ecotoxicol Environ Saf ; 273: 116148, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422791

RESUMO

The chiral pesticide hexythiazox was extensively employed in agricultural activities and has garnered growing concern for its harmful impact on the ecosystem. This study investigates the toxicodynamic earthworm at the enantiomeric level of hexythiazox. Earthworms exhibited notable enantioselectivity during the accumulation stage. Furthermore, the presence of earthworms can impact the rate of degradation and enantioselectivity of hexythiazox in soil. The accumulation of the two hexythiazox enantiomers in the earthworm adhered to the one-compartment model, whereas the elimination phase was governed by the first-order kinetics equation. Furthermore, it was discovered that there was no notable enantioselectivity observed during the elimination phase.


Assuntos
Oligoquetos , Praguicidas , Poluentes do Solo , Tiazolidinas , Animais , Solo , Praguicidas/toxicidade , Praguicidas/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/análise , Bioacumulação , Ecossistema , Estereoisomerismo
13.
Cell Death Dis ; 15(1): 27, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38199990

RESUMO

Intestinal epithelial renewal, which depends on the proliferation and differentiation of intestinal stem cells (ISCs), is essential for epithelial homoeostasis. Understanding the mechanism controlling ISC activity is important. We found that death receptor 5 (DR5) gene deletion (DR5-/-) mice had impaired epithelial absorption and barrier function, resulting in delayed weight gain, which might be related to the general reduction of differentiated epithelial cells. In DR5-/- mice, the expression of ISC marker genes, the number of Olfm4+ ISCs, and the number of Ki67+ and BrdU+ cells in crypt were reduced. Furthermore, DR5 deletion inhibited the expression of lineage differentiation genes driving ISC differentiation into enterocytes, goblet cells, enteroendocrine cells, and Paneth cells. Therefore, DR5 gene loss may inhibit the intestinal epithelial renewal by dampening ISC activity. The ability of crypts from DR5-/- mice to form organoids decreased, and selective DR5 activation by Bioymifi promoted organoid growth and the expression of ISC and intestinal epithelial cell marker genes. Silencing of endogenous DR5 ligand TRAIL in organoids down-regulated the expression of ISC and intestinal epithelial cell marker genes. So, DR5 expressed in intestinal crypts was involved in the regulation of ISC activity. DR5 deletion in vivo or activation in organoids inhibited or enhanced the activity of Wnt, Notch, and BMP signalling through regulating the production of Paneth cell-derived ISC niche factors. DR5 gene deletion caused apoptosis and DNA damage in transit amplifying cells by inhibiting ERK1/2 activity in intestinal crypts. Inhibition of ERK1/2 with PD0325901 dampened the ISC activity and epithelial regeneration. In organoids, when Bioymifi's effect in activating ERK1/2 activity was completely blocked by PD0325901, its role in stimulating ISC activity and promoting epithelial regeneration was also eliminated. In summary, DR5 in intestinal crypts is essential for ISC activity during epithelial renewal under homoeostasis.


Assuntos
Benzamidas , Difenilamina , Ftalimidas , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Células-Tronco , Tiazolidinas , Animais , Camundongos , Difenilamina/análogos & derivados , Homeostase
14.
Muscle Nerve ; 69(4): 498-503, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38294129

RESUMO

INTRODUCTION/AIMS: Oxaliplatin is a platinum-based anti-cancer drug widely used in colorectal cancer patients, but it may cause peripheral neuropathy. As one of the main causes of oxaliplatin-induced peripheral neuropathy (OPN) is oxidative stress, which is also a key factor causing diabetic peripheral neuropathy (DPN), the aim of this study was to evaluate the preventive effects of alpha-lipoic acid (ALA) and epalrestat (EP), which are used for the treatment of DPN, in an OPN zebrafish model. METHODS: Tg(nbt:dsred) transgenic zebrafish, with sensory nerves in the peripheral lateral line, were treated with oxaliplatin, oxaliplatin/EP, and oxaliplatin/ALA for 4 days. A confocal microscope was used to visualize and quantify the number of axon bifurcations in the distal nerve ending. To analyze the formation of synapses on sensory nerve terminals, quantification of membrane-associated guanylate kinase (MAGUK) puncta was performed using immunohistochemistry. RESULTS: The number of axon bifurcations and intensity of MAGUK puncta were significantly reduced in the oxaliplatin-treated group compared with those in the embryo medium-treated group. In both the oxaliplatin/EP and oxaliplatin/ALA-treated groups, the number of axon bifurcations and intensity of MAGUK puncta were greater than those in the oxaliplatin-treated group (p < .0001), and no significant difference was observed between larvae treated with oxaliplatin/ALA 1 µM and oxaliplatin/EP 1 µM (p = .4292). DISCUSSION: ALA and EP have protective effects against OPN in zebrafish. Our findings show that ALA and EP can facilitate more beneficial treatment for OPN.


Assuntos
Antineoplásicos , Doenças do Sistema Nervoso Periférico , Rodanina/análogos & derivados , Tiazolidinas , Ácido Tióctico , Animais , Humanos , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Peixe-Zebra , Oxaliplatina/toxicidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/prevenção & controle , Antineoplásicos/toxicidade
15.
Eur J Med Chem ; 266: 116139, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38252989

RESUMO

Diabetes is one of the fastest-growing metabolic disorders, nearly doubling the number of patients each year. There are different treatment approaches available for the management of diabetes, which lacks due to their side effects. The inhibition of enzymes involved in the metabolism of complex polysaccharides to monosaccharides has proven beneficial in patients with type 2 diabetes mellitus. Two enzymes, α-amylase and α-glucosidase, have emerged as potential drug targets and are widely explored for drug development against type 2 diabetes mellitus. In this context, thiazolidine-2,4-diones (TZDs) have emerged as potential drug candidates for developing newer molecules against α-amylase and α-glucosidase. Nineteen TZD-hybrids were synthesized and evaluated in vitro α-amylase and α-glucosidase inhibitory activity. The compounds 7i, 7k, and 7p have emerged as the best dual inhibitors with IC50 of 10.33 ± 0.11-20.94 ± 0.76 µM and 10.19 ± 0.25-24.07 ± 1.56 µM against α-glucosidase and α-amylase, respectively. The derivatives had good anti-oxidant activity, displaying IC50 = 14.95 ± 0.65-23.27 ± 0.99 µM. The compounds 7k and 7p showed the best inhibition of reactive oxygen species in the PNAC-1 cells. The molecules exhibit good binding within the active site of α-amylase (PDB id: 1B2Y) and α-glucosidase (PDB id: 3W37), displaying binding energies of -7.5 to -10.7 kcal/mol and -7.4 to -10.3 kcal/mol, respectively. Further, the compounds were nontoxic (LD50 = 500-1311 mg/kg) and possessed good GI absorption. The compounds 7i, 7k, and 7p were evaluated in vivo antidiabetic activity in an STZ-induced diabetic model in Wistar rats. The compound 7p emerged as the best compound in the in vivo studies; however, the activity was lesser than that of the standard drug pioglitazone.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Tiazolidinedionas , Humanos , Ratos , Animais , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Tiazolidinas/uso terapêutico , alfa-Glucosidases/metabolismo , Simulação de Acoplamento Molecular , Ratos Wistar , alfa-Amilases , Inibidores de Glicosídeo Hidrolases/química
16.
Nat Struct Mol Biol ; 31(2): 293-299, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177666

RESUMO

Transcription factors respond to multilevel stimuli and co-occupy promoter regions of target genes to activate RNA polymerase (RNAP) in a cooperative manner. To decipher the molecular mechanism, here we report two cryo-electron microscopy structures of Anabaena transcription activation complexes (TACs): NtcA-TAC composed of RNAP holoenzyme, promoter and a global activator NtcA, and NtcA-NtcB-TAC comprising an extra context-specific regulator, NtcB. Structural analysis showed that NtcA binding makes the promoter DNA bend by ∼50°, which facilitates RNAP to contact NtcB at the distal upstream NtcB box. The sequential binding of NtcA and NtcB induces looping back of promoter DNA towards RNAP, enabling the assembly of a fully activated TAC bound with two activators. Together with biochemical assays, we propose a 'DNA looping' mechanism of cooperative transcription activation in bacteria.


Assuntos
Proteínas de Bactérias , Compostos Nitrosos , Tiazolidinas , Tiocianatos , Transativadores , Transativadores/genética , Ativação Transcricional , Microscopia Crioeletrônica , Sequência de Bases , Proteínas de Bactérias/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Transcrição Gênica , Regulação Bacteriana da Expressão Gênica
17.
Cell Immunol ; 397-398: 104805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38244265

RESUMO

PIM kinases are over-expressed by a number of solid malignancies including breast cancer, and are thought to regulate proliferation, survival, and resistance to treatment, making them attractive therapeutic targets. Because PIM kinases sit at the nexus of multiple oncodriver pathways, PIM antagonist drugs are being tested alone and in conjunction with other therapies to optimize outcomes. We therefore sought to test the combination of pharmacological PIM antagonism and Th1-associated immunotherapy. We show that the pan PIM antagonist, AZD1208, when combined in vitro with Th1 cytokines IFN-γ and TNF-α, potentiates metabolic suppression, overall cell death, and expression of apoptotic markers in human breast cancer cell lines of diverse phenotypes (HER-2pos/ERneg, HER-2pos/ERpos and triple-negative). Interestingly, AZD1208 was shown to moderately inhibit IFN-γ secretion by stimulated T lymphocytes of both human and murine origin, suggesting some inherent immunosuppressive activity of the drug. Nonetheless, when multiplexed therapies were tested in a murine model of HER-2pos breast cancer, combinations of HER-2 peptide-pulsed DCs and AZD1208, as well as recombinant IFN-γ plus AZD1208 significantly suppressed tumor outgrowth compared with single-treatment and control groups. These studies suggest that PIM antagonism may combine productively with certain immunotherapies to improve responsiveness.


Assuntos
Antineoplásicos , Compostos de Bifenilo , Neoplasias , Proteínas Proto-Oncogênicas c-pim-1 , Tiazolidinas , Humanos , Animais , Camundongos , Citocinas , Antineoplásicos/farmacologia , Imunoterapia , Proliferação de Células , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia
18.
Metab Syndr Relat Disord ; 22(2): 90-96, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38165660

RESUMO

Background and Aims: Teneligliptin is an oral antidiabetic agent, it can persevere glucagon-like peptide-1 (GLP-1) by inhibiting dipeptidyl peptidase enzyme. In addition, it has rare incidence of hypoglycemia. Hence, this study aimed to test the effect of teneligliptin 20 mg twice daily along with low carbohydrate diet and physical exercise on change of body weight and insulin resistance in nondiabetic obese subjects. Materials and Methods: It is a prospective, randomized, double-blind, placebo-controlled, parallel group study carried out at outpatient department of an endocrinology hospital over the period of 48 weeks. Teneligliptin 20 mg twice daily 30 min before food (low carbohydrate diet [LCD]) with regular physical exercise, and control group was kept with placebo twice daily 30 min before food LCD with regular physical exercise. This study was registered in clinical trial registry of India [CTRI/2020/02/023329]. Results: A total of 150 nondiabetic obese subjects were randomized into test (n = 75) and control groups (n = 75). At the end of 48 weeks there was significant improvement in GLP-1, simplified nutrition assessment questionnaire (SNAQ) score, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG), and body weight. The mean difference and 95% confidence interval of GLP-1 (pg/mL) was 76.42 (44.42-148.41) (P = 0.37); SNAQ score, -1.64 (-2.48 to -0.81) (P = 0.000); HOMA-IR, -0.9 (-0.59 to -0.38) (P = 0.000); TG (mg/dL) -29.37 (-44.46 to -14.07) (P = 0.000); reduction of body weight (kilograms) -3.09 (-6.11 to -0.07) (P = 0.043). Conclusion: Findings of this study reveals that teneligliptin-treated group showed significant improvement in GLP-1 levels, reduced insulin resistance, body weight, TG, appetite, and metabolic syndrome. Teneligliptin is well tolerated, except in upper respiratory tract infections. CTR number: CTRI/2020/02/023329.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Resistência à Insulina , Pirazóis , Tiazolidinas , Humanos , Peptídeo 1 Semelhante ao Glucagon , Diabetes Mellitus Tipo 2/epidemiologia , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Glicemia/metabolismo , Estudos Prospectivos , Hipoglicemiantes/farmacologia , Obesidade/tratamento farmacológico , Peso Corporal
19.
Foot Ankle Surg ; 30(3): 268-272, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38199925

RESUMO

BACKGROUND: Tibiotalocalcaneal arthrodesis (TTCA) is a salvage procedure to fuse the ankle and subtalar joints to treat severe ankle and hindfoot disease. Patients often have multiple operations before a TTCA. A below knee amputation (BKA) has major physical and psychological impacts. Our aim is to investigate the outcomes of these treatments in salvage situations, with a focus on objective functional measurements and patient reported outcome measures (PROMs). METHODS: 52 patients underwent TTCA with a retrograde intramedullary nail and contacted for clinical and functional assessments and compared to patients who underwent traumatic BKA. PROMS such as AOFAS score, SF-36 and foot function index (FFI), and objective functional outcome measures were used. RESULTS: Of the 52 TTCA patients, 28 patients were recruited for follow-up. 35.7% of patients had postoperative complications. Mean postoperative AOFAS score was 63.9 ± 8.4 (range, 47-81), FFI 48.8 ± 15.8 (range, 22.2-75.2). 11 BKA patients (mean age 46.4 years) were included as control group. BKA patients scored higher than the TTCA patients on SF-36 physical functioning (p < 0.01) and SF-36 mental health (p < 0.05) subscales. The flat-surface functional tests (timed up and go test, 2-minute walk test, 10-meter walk test) showed significantly (p < 0.05) better outcomes for the BKA compared to TTCA. CONCLUSIONS: A TTCA is a salvage procedure with high complication rates. Functional and psychometric results are reduced compared to the normal population. Patients after a BKA had significantly better scores on SF-36 functional and mental health subscales and better functional outcomes for flat ground activities compared to TTCA. Heterogeneity of the TTCA and BKA patient cohorts is a limitation of this study. With these results in mind, the outlook of a BKA is not necessarily a grim one. They may be used by surgeons to counsel patients preoperatively when managing complex ankle and hindfoot disease. LEVEL OF EVIDENCE: Level III, retrospective cohort study.


Assuntos
Pinos Ortopédicos , Equilíbrio Postural , Tiazolidinas , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos de Tempo e Movimento , Articulação do Tornozelo/cirurgia , Amputação Cirúrgica , Artrodese/métodos , Resultado do Tratamento
20.
Sci Total Environ ; 917: 169838, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38232838

RESUMO

Microbial remediation of polluted environments is the most promising and significant research direction in the field of bioremediation. In this study, chlorpyrifos and fosthiazate were selected as representative organophosphorus pesticides, wheat was the tested plant, and fluorescently labeled degrading Bacillus cereus G-H27 were the film-forming bacteria. Exogenous strengthening technology was used to establish degrading bacterial biofilms on the root surface of wheat. The influence of root surface-degrading bacterial biofilms on the enrichment of chlorpyrifos and fosthiazate in wheat was comprehensively evaluated. First, the fluorescently-labeled degrading bacteria G-H27 was constructed, and its film-forming ability was investigated. Second, the growth- promoting characteristics and degradation ability of the bacteria G-H27 were investigated. Finally, the degradation effect of the root surface-degrading bacterial biofilm on chlorpyrifos and fosthiazate was determined. The above research provides an important material basis and method for the bioremediation of pesticide-contaminated soil.


Assuntos
Clorpirifos , Praguicidas , Tiazolidinas , Clorpirifos/metabolismo , Praguicidas/metabolismo , Compostos Organofosforados/metabolismo , Rizosfera , Microbiologia do Solo , Biodegradação Ambiental , Bacillus cereus/metabolismo
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