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1.
Biol Trace Elem Res ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38580871

RESUMO

Different types of metals, including manganese (Mn), are constantly encountered in various environmental matrices due to natural and anthropogenic activities. They induce a sustained inflammatory response in various organs, which is considered to be an important priming event in the pathogenesis of several diseases. Mn-induced neuroinflammation and subsequent neurodegeneration are well recognized. However, emerging data suggest that occupationally and environmentally relevant levels may affect various organs, including the lungs. Therefore, the present study was carried out to investigate the effects of Mn (as Mn2+) exposure on the inflammatory response in human normal bronchial (BEAS-2B) and adenocarcinoma alveolar basal (A549) epithelial cells, as well as in murine macrophages (J774). Mn2+ exposure significantly induced mRNA and protein expression of various pro-inflammatory mediators (cytokines and chemokines) in all cells compared to corresponding vehicle controls. Furthermore, Mn2+ treatment also led to increased phosphorylation of extracellular-signal-regulated kinase (ERK)1/2 and nuclear factor-kappa B (NF-kB) p65 in both epithelial cells and macrophages. As expected, cells treated with inhibitors of ERK1/2 (PD98059) and NF-kB p65 (IMD0354) effectively mitigated the expression of various pro-inflammatory mediators induced by Mn2+, suggesting that ERK/NF-kB pathways have a critical role in the Mn2+-induced inflammatory response. Further, in vivo studies are required to confirm these in vitro findings to support clinical translation.

2.
Front Cell Infect Microbiol ; 13: 1120888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033485

RESUMO

The Oceanimonas sp. BPMS22-derived protein protease inhibitor (PPI) has been proven to shift macrophages towards an inflammatory state and reduce Leishmania donovani infection in vitro and in vivo. The current study explored and validated the mechanistic aspects of the PPI and Toll-like receptor (TLR) interaction. The PPI exhibited the upregulation of TLR2, TLR4, and TLR6 during treatment which was proven to orchestrate parasite clearance effectively. An in silico study confirmed the high interaction with TLR4 and PPI. Immune blotting confirmed the significant upregulation of TLR4 in macrophages irrespective of L. donovani infection. Pharmacological inhibition and immune blot study confirmed the involvement of the PPI in TLR4-mediated phosphorylation of p38 MAPK and dephosphorylation of ERK1/2, repolarizing to pro-inflammatory macrophage state against experimental visceral leishmaniasis. In addition, in TLR4 knockdown condition, PPI treatment failed to diminish M2 phenotypical markers (CD68, Fizz1, Ym1, CD206, and MSR-2) and anti-inflammatory cytokines (IL-4, IL-10, and TGF-ß). Simultaneously, the PPI failed to upregulate the M1 phenotypical markers and pro-inflammatory cytokines (IL-1ß, IL-6, IL-12, and IFN-γ) (p < 0.001) during the TLR4 knockdown condition. In the absence of TLR4, the PPI also failed to reduce the parasite load and T-cell proliferation and impaired the delayed-type hypersensitivity response. The absence of pro-inflammatory cytokines was observed during a co-culture study with PPI-treated macrophages (in the TLR4 knockdown condition) with day 10 T-cell obtained from L. donovani-infected mice. This study supports the immunotherapeutic potential of the PPI as it interacted with TLR4 and promoted macrophage repolarization (M2-M1) to restrict the L. donovani parasite burden and helps in the mounting immune response against experimental visceral leishmaniasis.


Assuntos
Anti-Infecciosos , Leishmania donovani , Leishmaniose Visceral , Leishmaniose , Animais , Camundongos , Receptor 4 Toll-Like/metabolismo , Inibidores de Proteases/metabolismo , Macrófagos , Citocinas/metabolismo , Leishmaniose/metabolismo , Antivirais/metabolismo , Inibidores Enzimáticos/metabolismo , Anti-Infecciosos/metabolismo
3.
ACS Appl Mater Interfaces ; 15(2): 3182-3191, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36622780

RESUMO

The two-dimensional network of boron atoms (borophene) has attracted attention for its ultralow molar mass and remarkable polymorphism. Synthesized polymorphs of borophene (striped, ß12, χ3, and honeycomb), so far, are all found to be metallic. Employing a genetic algorithm-based structure searching technique, here we discover an allotrope, clustered-P1, which is located very close to the global energy minimum. Clustered-P1 exhibits a bulk silicon-like band gap (1.08 eV) with symmetric effective masses (∼0.2 m0) for electrons and holes along the transport direction. Phonon dispersion and beyond room-temperature ab initio molecular dynamics studies further confirm its excellent dynamic and structural stability. Since two-dimensional semiconductors are promising silicon alternatives for complementary metal-oxide semiconductor (CMOS) technology extension, we further investigate the characteristics of clustered-P1-based transistors using self-consistent quantum transport models for channel lengths of 10-3 nm. The performance of these devices has been found to be balanced for p- and n-type transistors and meets the requirements of the International Roadmap for Devices and Systems (IRDS). Our study may aid in the experimental realization of the lightest high-performance transistor.

4.
Glycoconj J ; 40(1): 1-17, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36595117

RESUMO

Arachis hypogea L. protein fraction-2 (AHP-F2) from the Peanut shell was extracted and characterized and its potent immunomodulatory and anti-leishmanial role was determined in this present study. AHP-F2 was found to be a glycoprotein as the presence of carbohydrates were confirmed by the analysis of high-performance liquid chromatography (HPLC) yielded glucose, galactose, mannose, and xylose. AHP-F2 molecular mass was found to be ∼28 kDa as indicated in MALDI-TOF and peptide mass fingerprinting analysis followed by Mascot search. The peptide matches revealed the similarity of the mannose/glucose binding lectin with 71.07% in the BLAST analysis. After that, the 3D structure of the AHP-F2 model was designed and validated by the Ramachandran plot. The immunomodulatory role of AHP-F2 was established in murine peritoneal macrophages as induction of nitric oxide (NO), and stimulation of proinflammatory cytokines (IL-12 and IFN-γ) in a dose-dependent manner was observed. Interestingly, it was also found that AHP-F2 has interacted with the innate immune receptor, toll-like receptors (TLRs) as established in molecular docking as well as mRNA expression. The anti-leishmanial potential of AHP-F2 was revealed with a prominent inhibition of amastigote growth within the murine macrophages with prompt induction of nitrite release. Altogether, the isolated AHP-F2 from Arachis hypogea L. has strong immunomodulatory and anti-leishmanial potential which may disclose a new path to treat leishmaniasis.


Assuntos
Arachis , Leishmania donovani , Animais , Camundongos , Manose , Ativação de Macrófagos , Simulação de Acoplamento Molecular , Glicoproteínas , Glucose , Leishmania donovani/metabolismo , Óxido Nítrico/metabolismo , Camundongos Endogâmicos BALB C
5.
Patterns (N Y) ; 3(12): 100625, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36569550

RESUMO

Monte Carlo (MC) simulation of the classical Heisenberg model has become the de facto tool to estimate the Curie temperature (T C) of two-dimensional (2D) magnets. As an alternative, here we develop data-driven models for the five most common crystal types, considering the isotropic and anisotropic exchange of up to four nearest neighbors and the single-ion anisotropy. We sample the 20-dimensional Heisenberg spin Hamiltonian and conceive a bisection-based MC technique to simulate a quarter of a million materials for training deep neural networks, which yield testing R 2 scores of nearly 0.99. Since 2D magnetism has a natural tendency toward low T C, learning-from-data is combined with data-from-learning to ensure a nearly uniform final data distribution over a wide range of T C (10-1,000 K). Global and local analysis of the features confirms the models' interpretability. We also demonstrate that the T C can be accurately estimated by a purely first-principles-based approach, free from any empirical corrections.

6.
Int Immunopharmacol ; 112: 109281, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183681

RESUMO

The present study aimed to validate the potential of a novel serine protein protease inhibitor (PPI), purified from marine Oceanimonas sp. BPMS22, induced M2 to M1 repolarization of the macrophages to treat visceral leishmaniasis (VL). Peptide mass fingerprint of the purified trypsin digested PPI peptide was obtained using matrix-assisted laser desorption ionization-time of flight combined with tandem mass spectrometry (MALDI-TOF MS/MS) and the sequence was used to construct a 3D protein model by homology modelling. The IC50 of PPI were 25.28 ± 1.675 µg/mL and 0.415 ± 0.015 µg/mL against promastigotes and intracellular amastigotes, respectively, indicating the host-directed therapy using PPI. The PPI enhanced the effector molecule i.e., nitric oxide (NO), and dampened the arginase activity in a dose-dependent manner. In vitro studies revealed that the BPMS22-derived PPI significantly (p < 0.05) decreased the mRNA expressions of M2 markers (FIZZ-1, YM-1, CD206, Arg-1) and increased the mRNA expressions of M1 markers (iNOS, IL-1ß, IL-12) in rIL-4 + rIL-10 induced M2 macrophages. Interestingly, the BPMS22-derived PPI also significantly (p < 0.05) decreased the FIZZ-1, YM-1, CD206, and Arg-1; significantly (p < 0.05) increased iNOS, IL-12, and IFN-γ mRNA expression in L. donovani -infected murine macrophages, alongside the decreased parasite load in it. Hence, PPI has the potential to repolarize the cytokines (rIL-4 + rIL-10) pre-stimulated and L. donovani-infected M2 macrophages to M1 phenotype in vitro. A decrease in parasite burden after treatment with PPI indicated the acceleration of the parasite killing by enhancing the macrophage effector functions. Further, in vivo PPI treatment reduced hepatic and splenic Leishman donovan units (LDU) up to 93.34 % and 87.63 %, respectively. This was followed by a surge in pro-inflammatory cytokines and dampening anti-inflammatory cytokines (p < 0.01), which exhibited anti-VL immunity. These observations might open new perspectives on PPI in macrophage repolarization to treat VL.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Camundongos , Animais , Óxido Nítrico/metabolismo , Arginase/metabolismo , Inibidores de Proteases/metabolismo , Tripsina/metabolismo , Espectrometria de Massas em Tandem , Macrófagos , Citocinas/metabolismo , Interleucina-12/metabolismo , Imunidade , Serina/metabolismo , RNA Mensageiro/metabolismo
7.
Nanoscale ; 14(26): 9409-9418, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35730762

RESUMO

Two-dimensional (2D) magnetic materials inherit enormous potential to revolutionize next-generation spintronic technology. The majority of prior investigations using 2D ferromagnet-based tunnel junctions have shown encouraging tunnel magnetoresistance (TMR) at low temperatures. Using first-principles-based calculations, here we investigate the magnetic properties of commercially available Cr2C crystals at their monolayer limit and reveal their half metallicity properties far beyond room temperature. We then design hetero-multilayer structures combining Cr2C with graphene and hexagonal boron nitride (h-BN) and report their magnetoresistance using spin-polarized quantum transport calculations. While graphene based devices, adsorbed on the metal contact, reveal a very high TMR (1200%), it can be further increased to 1500% by changing the barrier layer to h-BN. The dependence of TMR on the number of barrier layers and different metallic electrode materials (Ti, Ag, and Au) are also studied. Our investigation suggests that Cr2C based spin valves can serve as the perfect building blocks for room temperature all-2D spintronic devices.

8.
Microb Pathog ; 167: 105585, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35569694

RESUMO

Methicillin resistant Staphylococcus aureus (MRSA) is a prime pathogen responsible for various infections in human beings. Expression of virulence factors is a biggest challenge in MRSA, which results in failure of conventional antibiotic therapy. In connection to the search for natural and safe anti-virulence compounds, the present study focused to evaluate the anti-virulence potential of catechin-in-cyclodextrin-in-phospholipid liposome (CCPL) on MRSA strains. CCPL inhibited young biofilm (64.15-72.70%) as well degraded mature biofilm (55.60-63.65%) at ½ and » MIC doses, which was further confirmed by scanning electron microscopy and confocal laser scanning microscope studies. CCPL was capable enough to modify the surface hydrophobicity (40.26-48.59%), reduce the EPS production (1.71-2.25 folds) and bacterial motility. In addition, CCPL inhibited the synthesis of virulence factors like slime production (0.40-0.50 folds), DNase production, hemolytic activity (28.08-49.07%), proteolytic production (14.65-18.04%), lipase production, autolysis and cell auto-aggregation. CCPL prevented the staphyloxanthin production and thereby increased the susceptibility of MRSA strains towards H2O2. Further, CCPL significantly down-regulated the virulence genes (agrA, agrC, clfA, clfB, fnbA, fnbB, icaA, icaD, hla, hld, rna III, atlA, sarA, sigB & geh). Thus, the results of present study revealed that the CCPL can effectively reduce the virulence properties and its application could inhibit the pathogenicity and also prevents the development of drug-resistance in MRSA strains.


Assuntos
Catequina , Ciclodextrinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Catequina/farmacologia , Catequina/uso terapêutico , Ciclodextrinas/farmacologia , Ciclodextrinas/uso terapêutico , Regulação para Baixo , Humanos , Peróxido de Hidrogênio/farmacologia , Lipossomos/farmacologia , Testes de Sensibilidade Microbiana , Fosfolipídeos , Infecções Estafilocócicas/microbiologia , Virulência/genética , Fatores de Virulência/genética
9.
J Pharm Pharmacol ; 74(1): 103-111, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34109977

RESUMO

OBJECTIVES: Leukemia is one of the severe cancer types all around the globe. Even though some chemotherapeutic drugs are available for treating leukemia, they have various side effects. As an alternative approach, herbal drugs are focused on current research to overcome leukemia. The present work was conducted to investigate the antileukemic mechanism of active phytochemical vitexin, which was isolated from ethno-medicine (Prosopis cineraria leaf) used by traditional healers of West Bengal, India. METHODS: Antiproliferative mechanisms of selected phyto-compound against K-562 cells were evaluated using cellular uptake, morphological changes, DNA fragmentation, mitochondrial membrane potential and signaling pathways analysis. KEY FINDINGS: Vitexin exhibited cytotoxicity by reducing mitochondrial membrane potential (32.40%) and causing DNA fragmentation (84.15%). The western blotting study indicated inhibition of cell survival proteins (BCR, ABL, H-RAS, N-RAS, K-RAS and RAF) and expression of apoptotic proteins (p38, BAX and caspase-9) in leukemia cells upon treatment with vitexin. CONCLUSIONS: Based on the results, presently investigated phyto-compound vitexin could be considered for developing safe and natural drugs to treat leukemia after conducting suitable preclinical and clinical trials.


Assuntos
Apigenina/farmacologia , Proteínas Oncogênicas v-abl/metabolismo , Prosopis , Proteínas Proto-Oncogênicas c-bcr/metabolismo , Quinases raf/metabolismo , Proteínas ras/metabolismo , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Transdução de Sinais/efeitos dos fármacos
10.
Front Cell Infect Microbiol ; 11: 709316, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414131

RESUMO

Immune metabolic adaptation in macrophages by intracellular parasites is recognized to play a crucial role during Leishmania infection. However, there is little accessible information about changes in a metabolic switch in L. donovani infected macrophages. In previous studies, we have reported on the anti-leishmanial synergic effect of eugenol oleate with amphotericin B. In the present study, we demonstrated that glycolytic enzymes were highly expressed in infected macrophages during combinatorial treatment of eugenol oleate (2.5 µM) and amphotericin B (0.3125 µM). Additionally, we found that the biphasic role in arachidonic acid metabolite, PGE2, and LTB4, is released during this treatment. In vitro data showed that COX-2 mediated PGE2 synthesis increased significantly (p<0.01) in infected macrophages. Not only was the level of prostaglandin synthesis decreased 4.38 fold in infected macrophages after treatment with eugenol oleate with amphotericin B. The mRNA expression of PTGES, MPGES, and PTGER4 were also moderately expressed in infected macrophages, and found to be decreased in combinatorial treatment. In addition, NOS2 expression was activated by the phosphorylation of p38MAPK when combination-treated macrophages were promoted to kill intracellular parasites. The findings of the present study indicate that the synergism between eugenol oleate and amphotericin B could play an important role in immune metabolism adaptation with a concomitant increase in host immune response against the intracellular pathogen, L. donovani.


Assuntos
Leishmania donovani , Leishmaniose , Anfotericina B/farmacologia , Animais , Eugenol/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Ácido Oleico
11.
Int Immunopharmacol ; 98: 107847, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34126339

RESUMO

Asthma is a chronic inflammatory disease of the airways, which is characterized by infiltration of inflammatory cells, airway hyperresponsiveness (AHR), and airway remodeling. This study aimed to explore the role and mechanism of tannic acid (TA), a naturally occurring plant-derived polyphenol, in murine asthma model. BALB/c mice were given ovalbumin (OVA) to establish an allergic asthma model. The results revealed that TA treatment significantly decreased OVA-induced AHR, inflammatory cells infiltration, and the expression of various inflammatory mediators (Th2 and Th1 cytokines, eotaxin, and total IgE). Additionally, TA treatment also attenuated increases in mucins (Muc5ac and Muc5b) expression, mucus production in airway goblet cells, mast cells infiltration, and airway remodeling induced by OVA exposure. Furthermore, OVA-induced NF-κB (nuclear factor- kappa B) activation and cell adhesion molecules expression in the lungs was suppressed by TA treatment. In conclusion, TA effectively attenuated AHR, inflammatory response, and airway remodeling in OVA-challenged asthmatic mice. Therefore, TA may be a potential therapeutic option against allergic asthma in clinical settings.


Assuntos
Asma/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico , Taninos/uso terapêutico , Remodelação das Vias Aéreas , Alérgenos/imunologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Mucinas/metabolismo , Nozes/imunologia , Hipersensibilidade Respiratória , Células Th1 , Células Th2
12.
Mol Biol Rep ; 48(6): 5327-5334, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34156605

RESUMO

Myricitrin, a naturally occurring flavonoid in Madhuca longifolia, possesses several medicinal properties. Even though our earlier work revealed its role against the proliferation of acute myelogenous leukemia cells (HL-60), its molecular mechanisms have not yet been revealed. The current study aims to explore the molecular mechanisms of myricitrin (isolated from an ethnomedicinal drug Madhuca longifolia) to induce apoptosis in HL-60 cells. Treatment with IC-50 dose of myricitrin (353 µM) caused cellular shrinkage and cell wall damage in HL-60 cells compared to untreated control cells. Myricitrin treatment reduced the mitochondrial membrane potential (22.95%), increased DNA fragmentation (90.4%), inhibited the cell survival proteins (RAS, B-RAF, & BCL-2) and also induced pro-apoptotic proteins (p38, pro-caspase-3, pro-caspase-9 and caspase-3) in the HL-60 cells. The present study provides scientific evidence for the apoptosis caused by myricitrin in HL-60 leukemia cells. Hence, the phytochemical myricitrin could be considered as a potential candidate to develop an anticancer drug after checking its efficacy through suitable pre-clinical and clinical studies.


Assuntos
Flavonoides/farmacologia , Leucemia/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Flavonoides/metabolismo , Células HL-60 , Humanos , Leucemia/tratamento farmacológico , Madhuca/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismo
13.
Cytokine ; 146: 155623, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34144446

RESUMO

Conventional therapy of visceral leishmaniasis (VL) remains challenging with the pitfall of toxicity, drug resistance, and expensive. Hence, urgent need for an alternative approach is essential. In this study, we evaluated the potential of combination therapy with eugenol oleate and miltefosine in Leishmania donovani infected macrophages and in the BALB/c mouse model. The interactions between eugenol oleate and miltefosine were found to be additive against promastigotes and amastigotes with xΣFIC 1.13 and 0.68, respectively. Significantly (p < 0.001) decreased arginase activity, increased nitrite generation, improved pro-inflammatory cytokines, and phosphorylated p38MAPK were observed after combination therapy with eugenol oleate and miltefosine. >80% parasite clearance in splenic and hepatic tissue with concomitant nitrite generation, and anti-VL cytokines productions were observed after orally administered miltefosine (5 mg/kg body weight) and eugenol oleate (15 mg/kg body weight) in L. donovani-infected BALB/c mice. Altogether, this study suggested the possibility of an oral combination of miltefosine with eugenol oleate against visceral leishmaniasis.


Assuntos
Citocinas/metabolismo , Eugenol/uso terapêutico , Imunidade , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/imunologia , Óxido Nítrico/biossíntese , Fosforilcolina/análogos & derivados , Administração Oral , Animais , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Interações Medicamentosas , Quimioterapia Combinada , Eugenol/administração & dosagem , Eugenol/farmacologia , Feminino , Imunidade/efeitos dos fármacos , Concentração Inibidora 50 , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/crescimento & desenvolvimento , Leishmania donovani/imunologia , Leishmania donovani/ultraestrutura , Leishmaniose Visceral/parasitologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Macrófagos/ultraestrutura , Masculino , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Parasitos/efeitos dos fármacos , Parasitos/crescimento & desenvolvimento , Parasitos/imunologia , Parasitos/ultraestrutura , Fosforilação/efeitos dos fármacos , Fosforilcolina/administração & dosagem , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
J Phys Chem Lett ; 12(4): 1220-1227, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33492151

RESUMO

Monoelemental two-dimensional materials (borophene, silicene, etc.) are exciting candidates for electrodes in lithium-ion batteries because of their ultralight molar mass. However, these materials' lithium-ion binding mechanism can be complex as the inherited polymorphism may induce phase changes during the charge-discharge cycles. Here, we combine genetic-algorithm-based bottom-up and stochastic top-down structure searching techniques to conduct thermodynamic scrutiny of the lithiated compounds of 2D allotropes of four elements: B, Al, Si, and P. Our first-principles-based high-throughput computations unveil polymorphism-driven lithium-ion binding process and other nonidealities (e.g., bond cleavage, adsorbent phase change, and electroplating), which lacks mention in earlier works. While monolayer B (2479 mAh/g), Al (993 mAh/g), and Si (954 mAh/g) have been demonstrated here as excellent candidates for Li-ion storage, P falls short of the expectation. Our well-designed computational framework, which always searches for lithiated structures at global minima, provides convincing thermodynamical insights and realistic reversible specific-capacity values. This will expectedly open up future experimental efforts to design monoelemental two-dimensional material-based anodes with specific polymorphic structures.

15.
Int Immunopharmacol ; 91: 107291, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360084

RESUMO

Present treatment regimen on visceral leishmaniasis has multiple limitations including severe side effects, toxicity, and resistance of Leishmania strains. Amphotericin B is a well-established pharmacologically approved drug; however, mainly toxicity is a foremost issue with that drug. Recently, our group identified eugenol oleate as an anti-leishmanial immunomodulatory compound. The important objectives of this present study was to evaluate the possible synergistic effect of eugenol oleate with amphotericin B to reduce the toxicity of this approved drug. Results obtained from this study signified that combination of eugenol oleate and amphotericin B showed indifferent combinatorial effect against promastigotes with xΣFIC 1.015, while, moderate synergistic activity with xΣFIC 0.456 against amastigotes. It was also notable that eugenol oleate (2.5 µM) with low concentrations of amphotericin B (0.3125 µM) showed 96.45% parasite reduction within L. donovani-infected murine macrophages. Furthermore, eugenol oleate and amphotericin B significantly (p < 0.01) enhanced the nitrite generation, and pro-inflammatory cytokines (IL-12, IFN-γ and TNF-α) in infected macrophages in vitro and in BALB/c mice in vivo. Eugenol oleate (10 mg/Kg b. wt.) with amphotericin B (1 mg/Kg b.wt.) significantly (p < 0.01) controlled the parasite burden in liver by 96.2% and in spleen by 93.12%. Hence, this study strongly suggested the synergic potential of eugenol oleate with low concentration of amphotericin B in experimental visceral leishmaniasis through anti-leishmanial immune response.


Assuntos
Anfotericina B/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Macrófagos Peritoneais/efeitos dos fármacos , Tripanossomicidas/farmacologia , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Interações Hospedeiro-Parasita , Mediadores da Inflamação/metabolismo , Leishmania donovani/imunologia , Leishmania donovani/patogenicidade , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , Leishmaniose Visceral/parasitologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/parasitologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/parasitologia , Camundongos Endogâmicos BALB C , Nitritos/metabolismo , Carga Parasitária , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Baço/parasitologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/parasitologia , Equilíbrio Th1-Th2 , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/parasitologia
16.
Curr Comput Aided Drug Des ; 17(6): 759-772, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32703141

RESUMO

BACKGROUND: Human mitotic kinesins play a crucial role in mitotic cell division. Targeting the spindle separation phase of mitosis has gained much attention pharmaceutically in cancer chemotherapy. Spindle segregation is carried out mainly by Eg5 kinesin, and currently, it has many inhibitors in different phases of clinical trials. All the current drug candidates bind un-competitively with ATP/ADP at allosteric site 1 (formed by loop L5, helix α2 and helix α3). Recent experiments show that inhibitors that bind to the site 2 (formed by helix α4 and helix α6) are either competitive or uncompetitive to ATP/ADP. OBJECTIVES: To identify suitable lead compounds that target the mitotic kinesin Eg5, using in silico screening and their validation using in vitro and cell-based assays. METHODOLOGY: Potential inhibitors were screened for human Eg5 (kinesin-5) through structurebased virtual screening and the top-scoring compounds were validated using steady-state ATPase assay, differential scanning fluorimetry, and microscale thermophoresis. The anti-cancer activity of the compounds was evaluated in the epithelial (A549) and chronic myelogenous leukemia (K562) cancer cell lines. A known strong binding inhibitor, S-trityl-L-cystine, is used as a reference compound. RESULTS: Out of the many compounds tested, MM01 and MM03 showed good cell-based activity against the cancer cell lines A549 and K562 and can be further studied in animal models. CONCLUSION: In this study, a structure-based approach was used to identify the potential inhibitors and validate them using different in-vitro and cell-based assays.


Assuntos
Cinesinas , Neoplasias , Animais , Humanos , Mitose
17.
Cytokine ; 145: 155301, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33127258

RESUMO

Visceral leishmaniasis (VL) is an endemic fatal infectious disease in tropical and subtropical nations. The limited treatment options, long treatment regimens, invasive mode of administration of drugs, and lack of effective vaccination are the main reasons for the search of new alternative therapeutics against VL. On this quest, from a series of eugenol derivatives, we had demonstrated eugenol oleate as a lead immunomodulatory anti-VL molecule earlier. In this report, the oral efficacy and mechanism of eugenol oleate in inducing immunomodulatory anti-VL activity has been studied in BALB/c mice model. The plasma pharmacokinetic and acute toxicity studies suggested that the eugenol oleate is safe with an appreciable pharmacokinetic profile. Eugenol oleate (30 mg/kg B.W.) showed 86.5% of hepatic and 84.1% of splenic parasite clearance. The increased Th1 cytokine profile and decreased Th2 cytokine profile observed from ELISA and qRTPCR suggested that the eugenol oleate induced the parasite clearance through the activation of the host immune system. Subsequently, the mechanistic insights behind the anti-leishmanial activity of eugenol oleate were studied in peritoneal macrophages in vitro by inhibitor response study and immunoblotting. The results inferred that eugenol oleate activated the PKC-ßII-p38 MAPK and produced IL-12 and IFN-γ which intern activated the iNOS2 to produce NO free radicals that cleared the intracellular parasite.


Assuntos
Eugenol/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Ácido Oleico/farmacologia , Administração Oral , Animais , Citocinas , Modelos Animais de Doenças , Feminino , Sistema Imunitário/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/parasitologia
18.
J Phys Chem Lett ; 11(15): 6291-6298, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32698581

RESUMO

Charge density wave (CDW) materials are an important subclass of two-dimensional materials exhibiting significant resistivity switching with the application of external energy. However, the scarcity of such materials impedes their practical applications in nanoelectronics. Here we combine a first-principles-based structure-searching technique and unsupervised machine learning to develop a fully automated high-throughput computational framework, which identifies CDW phases from a unit cell with inherited Kohn anomaly. The proposed methodology not only rediscovers the known CDW phases but also predicts a host of easily exfoliable CDW materials (30 materials and 114 phases) along with associated electronic structures. Among many promising candidates, we pay special attention to ZrTiSe4 and conduct a comprehensive analysis to gain insight into the Fermi surface nesting, which causes significant semiconducting gap opening in its CDW phase. Our findings could provide useful guidelines for experimentalists.

19.
Inflammopharmacology ; 28(5): 1301-1314, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32372165

RESUMO

Pulmonary fibrosis (PF) is a chronic and irreversible scarring disease in the lung with limited treatment options. Therefore, it is critical to identify new therapeutic options. This study was undertaken to identify the effects of tannic acid (TA), a naturally occurring dietary polyphenol, in a mouse model of PF. Bleomycin (BLM) was intratracheally administered to induce PF. Administration of TA significantly reduced BLM-induced histological alterations, inflammatory cell infiltration and the levels of various inflammatory mediators (nitric oxide, leukotriene B4 and cytokines). Additionally, treatment with TA also impaired BLM-mediated increases in pro-fibrotic (transforming growth factor-ß1) and fibrotic markers (alpha-smooth muscle actin, vimentin, collagen 1 alpha and fibronectin) expression. Further investigation indicated that BLM-induced phosphorylation of Erk1/2 (extracellular signal-regulated kinases 1 and 2) in lungs was suppressed by TA treatment. Findings of this study suggest that TA has the potential to mitigate PF through inhibiting the inflammatory response and fibrotic process in lungs and that TA might be useful for the treatment of PF in clinical practice.


Assuntos
Anti-Inflamatórios/farmacologia , Fibrose Pulmonar/tratamento farmacológico , Taninos/farmacologia , Animais , Bleomicina , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/patologia
20.
Sci Rep ; 10(1): 6670, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317660

RESUMO

Investigation of quantum spin Hall states in 1T' phase of the monolayer transition metal dichalcogenides has recently attracted the attention for its potential in nanoelectronic applications. While most of the theoretical findings in this regard deal with infinitely periodic crystal structures, here we employ density functional theory calculations and [Formula: see text] Hamiltonian based continuum model to unveil the bandgap opening in the edge-state spectrum of finite width molybdenum disulphide, molybdenum diselenide, tungsten disulphide and tungsten diselenide. We show that the application of a perpendicular electric field simultaneously modulates the band gaps of bulk and edge-states. We further observe that tungsten diselenide undergoes a semi-metallic intermediate state during the phase transition from topological to normal insulator. The tuneable edge conductance, as obtained from the Landauer-Büttiker formalism, exhibits a monotonous increasing trend with applied electric field for deca-nanometer molybdenum disulphide, whereas the trend is opposite for other cases.

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