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1.
Small ; 19(14): e2204637, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36642859

RESUMO

Interest in the development of new generation injectable bone cements having appropriate mechanical properties, biodegradability, and bioactivity has been rekindled with the advent of nanoscience. Injectable bone cements made with calcium sulfate (CS) are of significant interest, owing to its compatibility and optimal self-setting property. Its rapid resorption rate, lack of bioactivity, and poor mechanical strength serve as a deterrent for its wide application. Herein, a significantly improved CS-based injectable bone cement (modified calcium sulfate termed as CSmod ), reinforced with various concentrations (0-15%) of a conductive nanocomposite containing gold nanodots and nanohydroxyapatite decorated reduced graphene oxide (rGO) sheets (AuHp@rGO), and functionalized with vancomycin, is presented. The piezo-responsive cement exhibits favorable injectability and setting times, along with improved mechanical properties. The antimicrobial, osteoinductive, and osteoconductive properties of the CSmod cement are confirmed using appropriate in vitro studies. There is an upregulation of the paracrine signaling mediated crosstalk between mesenchymal stem cells and human umbilical vein endothelial cells seeded on these cements. The ability of CSmod to induce endothelial cell recruitment and augment bone regeneration is evidenced in relevant rat models. The results imply that the multipronged activity exhibited by the novel-CSmod cement would be beneficial for bone repair.


Assuntos
Cimentos Ósseos , Nanocompostos , Ratos , Animais , Humanos , Cimentos Ósseos/farmacologia , Durapatita , Ouro , Sulfato de Cálcio , Células Endoteliais , Regeneração Óssea , Fosfatos de Cálcio , Força Compressiva
2.
J Biochem Mol Toxicol ; 37(11): e23472, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37462223

RESUMO

Sesamol, a lignan obtained from roasted seeds of Sesamum indicum, has high antioxidant and anti-inflammatory activity. In this study, we have investigated the effect of sesamol on Bleomycin (BLM) induced pulmonary toxicity as well as fibrosis in Wistar rats. Lung toxicity was induced by administration of BLM, 0.015 U/g ip, twice weekly for 28 days whereas lung fibrosis was induced by BLM, 0.015 U/g ip, every 5th day for 49 days. Sesamol administration was started 7 days before first dose of BLM in both the models. It was observed that sesamol 50 mg/kg most effectively attenuated pulmonary toxicity by reducing oxidative stress, inflammation and apoptosis. This dose was further evaluated for its anti-fibrotic effect. It was observed that there was a significant reduction in fibrosis. Lung collagen content was markedly reduced. Furthermore, expression of pro-fibrotic proteins, TGF-ß/SMAD and α-SMA, was reduced and that of anti-fibrotic protein, AMPK, was markedly increased. Even though the combination of sesamol with pirfenidone exhibited no additional protection than either drug alone, it is evident from our study that our test drug, sesamol is comparable in efficacy to pirfenidone. Thus, sesamol has promising therapeutic potential in treatment of pulmonary toxicity and fibrosis.


Assuntos
Bleomicina , Fibrose Pulmonar , Ratos , Animais , Bleomicina/toxicidade , Ratos Wistar , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/prevenção & controle , Pulmão/metabolismo , Fibrose
3.
J Biochem Mol Toxicol ; 34(2): e22431, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31833131

RESUMO

Cisplatin-induced nephrotoxicity persists as a clinical problem despite several supportive measures to alleviate renal damage. Daidzein (DZ), a dietary isoflavone having antioxidant and anti-inflammatory activity, is investigated in this study for protective effects against cisplatin-induced renal injury in rats. DZ (25, 50, or 100 mg/kg; intraperitoneally; 10 days) was administered along with Cisplatin, single dose, on the 7th day of the experiment. On the 11th day, the rats were euthanized, and different samples were collected for analysis. Biochemical, histopathological, and molecular parameters were assessed to evaluate the effect of daidzein. Cisplatin injection resulted in renal dysfunction, lipid peroxidation that led to consumption of antioxidants, exaggerated apoptosis, and inflammation. These changes were associated with increase in the signaling proteins. DZ attenuated the toxic effects of cisplatin on the kidney at 100 mg/kg dose. The study concludes with the finding that daidzein imparts protection against the nephrotoxic effect of Cisplatin and can be considered as a novel, potential therapy.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/dietoterapia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Isoflavonas/uso terapêutico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nefrite/dietoterapia , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Cisplatino/efeitos adversos , Citocinas/sangue , Isoflavonas/administração & dosagem , Isoflavonas/farmacologia , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Ratos , Resultado do Tratamento
4.
Bioinformatics ; 32(3): 338-44, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26454276

RESUMO

MOTIVATION: In the post-genomic era, automatic annotation of protein sequences using computational homology-based methods is highly desirable. However, often protein sequences diverge to an extent where detection of homology and automatic annotation transfer is not straightforward. Sophisticated approaches to detect such distant relationships are needed. We propose a new approach to identify deep evolutionary relationships of proteins to overcome shortcomings of the available methods. RESULTS: We have developed a method to identify remote homologues more effectively from any protein sequence database by using several cascading events with Hidden Markov Models (C-HMM). We have implemented clustering of hits and profile generation of hit clusters to effectively reduce the computational timings of the cascaded sequence searches. Our C-HMM approach could cover 94, 83 and 40% coverage at family, superfamily and fold levels, respectively, when applied on diverse protein folds. We have compared C-HMM with various remote homology detection methods and discuss the trade-offs between coverage and false positives. AVAILABILITY AND IMPLEMENTATION: A standalone package implemented in Java along with a detailed documentation can be downloaded from https://github.com/RSLabNCBS/C-HMM SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online. CONTACT: mini@ncbs.res.in.


Assuntos
Análise de Sequência de Proteína/métodos , Homologia de Sequência de Aminoácidos , Algoritmos , Análise por Conglomerados , Bases de Dados de Proteínas , Cadeias de Markov , Proteínas/química , Proteínas/classificação , Proteínas/genética , Alinhamento de Sequência
5.
BMC Plant Biol ; 15: 212, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26315624

RESUMO

BACKGROUND: Krishna Tulsi, a member of Lamiaceae family, is a herb well known for its spiritual, religious and medicinal importance in India. The common name of this plant is 'Tulsi' (or 'Tulasi' or 'Thulasi') and is considered sacred by Hindus. We present the draft genome of Ocimum tenuiflurum L (subtype Krishna Tulsi) in this report. The paired-end and mate-pair sequence libraries were generated for the whole genome sequenced with the Illumina Hiseq 1000, resulting in an assembled genome of 374 Mb, with a genome coverage of 61 % (612 Mb estimated genome size). We have also studied transcriptomes (RNA-Seq) of two subtypes of O. tenuiflorum, Krishna and Rama Tulsi and report the relative expression of genes in both the varieties. RESULTS: The pathways leading to the production of medicinally-important specialized metabolites have been studied in detail, in relation to similar pathways in Arabidopsis thaliana and other plants. Expression levels of anthocyanin biosynthesis-related genes in leaf samples of Krishna Tulsi were observed to be relatively high, explaining the purple colouration of Krishna Tulsi leaves. The expression of six important genes identified from genome data were validated by performing q-RT-PCR in different tissues of five different species, which shows the high extent of urosolic acid-producing genes in young leaves of the Rama subtype. In addition, the presence of eugenol and ursolic acid, implied as potential drugs in the cure of many diseases including cancer was confirmed using mass spectrometry. CONCLUSIONS: The availability of the whole genome of O.tenuiflorum and our sequence analysis suggests that small amino acid changes at the functional sites of genes involved in metabolite synthesis pathways confer special medicinal properties to this herb.


Assuntos
Regulação da Expressão Gênica de Plantas , Genoma de Planta , Ocimum/genética , Índia , Ocimum/metabolismo , Folhas de Planta/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo
6.
Proteins ; 82(7): 1428-43, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24500901

RESUMO

Prolyl oligopeptidase (POP) is a serine protease, unique for its ability to cleave various small oligopeptides shorter than 30 amino acids. POP is an important drug target since it is implicated in various neurological disorders. Although there is structural evidence that bacterial POPs undergo huge interdomain movements and acquire an "open" state in the substrate-unbound form, hitherto, no crystal structure is available in the substrate-unbound domain-open form of eukaryotic POPs. Indeed, there is no difference between the substrate-unbound/bound states of eukaryotic POPs. This raises unanswered questions about whether difference in the substrate access pathway exists between bacterial and eukaryotic POPs. Here, we have used normal mode analysis and molecular dynamics to unravel the mechanism of substrate entry in mammalian POPs, which has been debated until now. Motions observed using normal modes of porcine and bacterial POPs were analyzed and compared, augmented by molecular dynamics of these proteins. Identical to bacterial POPs, interdomain opening was found to be the possible pathway for the substrate-gating in mammals as well. On the basis of our analyses and evidences, a mechanistic model of substrate entry in POPs has been proposed. Up-down movement of N-terminal hydrolase domain resulted in twisting motion of two domains, followed by the conformational changes of interdomain loop regions, which facilitate interdomain opening. Similar to bacterial POPs, an open form of porcine POP is also proposed with domain-closing motion. This work has direct implications for the development of novel inhibitors of mammalian POPs to understand the etiology of various neurological diseases.


Assuntos
Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Animais , Domínio Catalítico , Prolil Oligopeptidases , Especificidade por Substrato , Suínos
7.
BMC Genomics ; 15: 985, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25407321

RESUMO

BACKGROUND: Prolyl oligopeptidases (POPs) are proteolytic enzymes, widely distributed in all the kingdoms of life. Bacterial POPs are pharmaceutically important enzymes, yet their functional and evolutionary details are not fully explored. Therefore, current analysis is aimed at understanding the distribution, domain architecture, probable biological functions and gene family expansion of POPs in bacterial and archaeal lineages. RESULTS: Exhaustive sequence analysis of 1,202 bacterial and 91 archaeal genomes revealed ~3,000 POP homologs, with only 638 annotated POPs. We observed wide distribution of POPs in all the analysed bacterial lineages. Phylogenetic analysis and co-clustering of POPs of different phyla suggested their common functions in all the prokaryotic species. Further, on the basis of unique sequence motifs we could classify bacterial POPs into eight subtypes. Analysis of coexisting domains in POPs highlighted their involvement in protein-protein interactions and cellular signaling. We proposed significant extension of this gene family by characterizing 39 new POPs and 158 new α/ß hydrolase members. CONCLUSIONS: Our study reflects diversity and functional importance of POPs in bacterial species. Many genomes with multiple POPs were identified with high sequence variations and different cellular localizations. Such anomalous distribution of POP genes in different bacterial genomes shows differential expansion of POP gene family primarily by multiple horizontal gene transfer events.


Assuntos
Archaea/enzimologia , Bactérias/enzimologia , Evolução Molecular , Filogenia , Serina Endopeptidases/química , Serina Endopeptidases/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Archaea/citologia , Archaea/genética , Bactérias/citologia , Bactérias/genética , Membrana Celular/enzimologia , Análise por Conglomerados , Sequência Conservada , Transferência Genética Horizontal , Genoma Bacteriano/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Prolil Oligopeptidases , Estrutura Terciária de Proteína , Transporte Proteico , Homologia de Sequência do Ácido Nucleico , Serina Endopeptidases/classificação , Serina Endopeptidases/metabolismo
8.
Sci Rep ; 14(1): 3694, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355954

RESUMO

Individual cancers are composed of heterogeneous tumor cells with distinct phenotypes and genotypes, with triple negative breast cancers (TNBC) demonstrating the most heterogeneity among breast cancer types. Variability in transcriptional phenotypes could meaningfully limit the efficacy of monotherapies and fuel drug resistance, although to an unknown extent. To determine if transcriptional differences between tumor cells lead to differential drug responses we performed single cell RNA-seq on cell line and PDX models of breast cancer revealing cell subpopulations in states associated with resistance to standard-of-care therapies. We found that TNBC models contained a subpopulation in an inflamed cellular state, often also present in human breast cancer samples. Inflamed cells display evidence of heightened cGAS/STING signaling which we demonstrate is sufficient to cause tumor cell resistance to chemotherapy. Accordingly, inflamed cells were enriched in human tumors taken after neoadjuvant chemotherapy and associated with early recurrence, highlighting the potential for diverse tumor cell states to promote drug resistance.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Transdução de Sinais , Fenótipo
9.
Nanoscale ; 14(5): 1713-1722, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35072191

RESUMO

The extensive and indiscriminate use of antibiotics in the ongoing COVID-19 pandemic might significantly contribute to the growing number of multiple drug resistant (MDR) bacteria. With the dwindling pipeline of new and effective antibiotics, we might soon end up in a post-antibiotic era, in which even common bacterial infections would be a challenge to control. To prevent this, an antibiotic-free strategy would be highly desirable. Magnetic nanoparticle (MNP)-mediated hyperthermia-induced antimicrobial therapy is an attractive option as it is considered safe for human use. Given that iron and zinc are critical for bacterial virulence, we evaluated the response of multiple pathogenic bacteria to these elements. Treatment with 1 mM iron and zinc precursors resulted in the intracellular biosynthesis of MNPs in multiple Gram-positive and Gram-negative disease-causing bacteria. The superparamagnetic nanoparticles in the treated bacteria/biofilms, generated heat upon exposure to an alternating magnetic field (AMF), which resulted in an increase in the temperature (5-6 °C) of the milieu with a subsequent decrease in bacterial viability. Furthermore, we observed for the first time that virulent bacteria derived from infected samples harbour MNPs, suggesting that the bacteria had biosynthesised the MNPs using the metal ions acquired from the host. AMF treatment of the bacterial isolates from the infected specimens resulted in a strong reduction in viability (3-4 logs) as compared to vancomycin/ciprofloxacin treatment. The therapeutic efficacy of the MNPs to induce bacterial death with AMF alone was confirmed ex vivo using infected tissues. Our proposed antibiotic-free approach for killing bacteria using intracellular MNPs is likely to evolve as a promising strategy to combat a wide range of bacterial infections.


Assuntos
Infecções Bacterianas , COVID-19 , Nanopartículas de Magnetita , Antibacterianos/farmacologia , Bactérias , Infecções Bacterianas/tratamento farmacológico , Humanos , Pandemias , SARS-CoV-2
10.
Mater Sci Eng C Mater Biol Appl ; 119: 111584, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321630

RESUMO

3D biopolymeric scaffolds often lack the biochemical cues and mechanical strength to encourage bone tissue regeneration. Chemical crosslinkers have been extensively used to impart strength, but have been found to be toxic at the site of implantation and possess a lacuna in physical strength. We attempted to address this by engineering a self-crosslinked polymer through the in-situ reduction of Graphene oxide (GO) in a gelatin cryogel (Gel-RGO) using ice as a template to create pores. Superior osteoinductive and antimicrobial properties were further endowed on the cryogel by incorporating silver nanoparticles decorated nanohydroxyapatite in the Gel-RGOAg@Hap(2%) cryogel. The optimized biocompatible cryogel favoured bone cell adhesion and its proliferation. The osteoconductive and osteoinductive potential of the cryogel was confirmed through biomineralization and differentiation of bone cells. In addition, these cryogels showed prolonged antimicrobial activity against S. aureus. This investigation exhibits the achievability/prospect of building up an ideal gelatin platform without the utilization of an outside crosslinking agent via manipulating the conditions of gelation. The superior crosslinking achieved between gelatin and GO, in addition to its ability to support bone formation and prevent infection make this cryogel an attractive candidate for bone tissue engineering applications.


Assuntos
Anti-Infecciosos , Criogéis , Nanopartículas Metálicas , Osteogênese , Animais , Linhagem Celular , Fibroblastos , Gelatina , Grafite , Gelo , Camundongos , Osteoblastos , Porosidade , Prata/farmacologia , Staphylococcus aureus , Engenharia Tecidual , Alicerces Teciduais
11.
Int J Biol Macromol ; 190: 474-486, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508717

RESUMO

The ECM of cartilage is composed of proteoglycans (PG) that contain glycosaminoglycan (GAG), aggrecan, hyaluronic acid (HA) and other molecular components which play an important role in regulating chondrocyte functions via cell-matrix interactions, integrin-mediated signalling etc. Implantation of chondrocytes encapsulated in scaffolds that mimic the micro-architecture of proteoglycan, is expected to enhance cartilage repair. With an aim to create a hydrogel having macromolecular structure that resembles the cartilage-specific ECM, we constructed a hierarchal structure that mimic the PG. The bottle brush structure of the aggrecan was obtained using chondroitin sulphate and carboxymethyl cellulose which served as GAG and core protein mimic respectively. A proteoglycan-like structure was obtained by cross-linking it with modified chitosan that served as a HA substitute. The physico-chemical characteristics of the above cross-linked injectable hydrogel supported long term human articular chondrocyte subsistence and excellent post-injection viability. The chondrocytes encapsulated in the PMH expressed significant levels of articular cartilage specific markers like collagen II, aggrecan, GAGs etc., indicating the ability of the hydrogel to support chondrocyte differentiation. The biocompatibility and biodegradability of the hydrogels was confirmed using suitable in vivo studies. The results revealed that the PG-mimetic hydrogel could serve as a promising scaffold for chondrocyte implantation.


Assuntos
Condrócitos/citologia , Condrogênese , Hidrogéis/química , Hidrogéis/farmacologia , Injeções , Proteoglicanas/química , Animais , Carboximetilcelulose Sódica/química , Bovinos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Imobilizadas/citologia , Células Imobilizadas/efeitos dos fármacos , Quitosana/análogos & derivados , Quitosana/química , Condrócitos/efeitos dos fármacos , Condrócitos/ultraestrutura , Condrogênese/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Módulo de Elasticidade , Humanos , Ratos Sprague-Dawley , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Bioorg Med Chem Lett ; 20(16): 4945-50, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20621472

RESUMO

The search for small molecules that preferentially target the functionally important surfaces of estrogen receptor and disrupt the transcriptional activity in the cell has emerged as a promising area towards rationale based drug design. Herein, we report substituted styryl chromones as a new class of compounds that exhibit selectivity for ERbeta binding at the second binding site of HT and antiproliferative activity in human breast cancer cell line.


Assuntos
Antineoplásicos/síntese química , Benzopiranos/síntese química , Cromonas/química , Estirenos/síntese química , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Benzopiranos/farmacologia , Benzopiranos/uso terapêutico , Sítios de Ligação , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cromonas/uso terapêutico , Cromonas/toxicidade , Simulação por Computador , Desenho de Fármacos , Receptor beta de Estrogênio/química , Feminino , Humanos , Estirenos/farmacologia , Estirenos/uso terapêutico , Termodinâmica
13.
Carbohydr Polym ; 235: 115975, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122506

RESUMO

The control of blood flow from breached blood vessels during surgery or trauma is challenging. With the existing treatment options being either expensive or ineffective, the development of a haemostat that overcome such drawbacks would be beneficial. With an aim to develop an ideal haemostat, the potential of sodium starch glycolate (SSG), a commonly used pharmaceutical disintegrant was modified to obtain porous microparticles (pSSG). The biodegradability, cyto-compatibility and haemo-compatibility of the modified particles were confirmed using appropriate studies. In comparison to starch and SSG, the irregular shaped pSSG demonstrated spontaneous and significant fluid absorption (3500+500 %) and formed a physical barrier to blood flow. In addition, significant blood cells aggregation and platelet activation was observed in the modified micoparticles leading to rapid clot formation. In-vivo studies on liver and abdominal artery injury models in rats indicated the superior haemostatic potential of pSSG over SSG and starch. The results indicated that pSSG can be explored further in clinical evaluation as a hemostat.


Assuntos
Hemostáticos/farmacologia , Amido/análogos & derivados , Eritrócitos/efeitos dos fármacos , Hemostáticos/síntese química , Hemostáticos/química , Humanos , Tamanho da Partícula , Agregação Plaquetária/efeitos dos fármacos , Porosidade , Amido/síntese química , Amido/química , Amido/farmacologia , Propriedades de Superfície
14.
ACS Appl Bio Mater ; 3(2): 779-788, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35019282

RESUMO

Despite the promising role of magnetic hyperthermia in cancer therapy, its use in patients has been restricted by hurdles that include inefficient targeting of magnetic particles to the tumor site, limited bioavailability, and high toxicity, etc. Taking advantage of the unique metabolic property of cancer cells, we explored the potential of these cells to biosynthesize magnetic nanoparticles for potential hyperthermia applications. Treatment of cancer cells with a mixture of FeCl2 and zinc gluconate resulted in a significant increase in intracellular Fe and Zn content in these cells. Exposure of these cells to an alternating magnetic field (AMF) for 30 min resulted in a substantial temperature rise of 5-6 °C. The in situ formed particles were identified as iron oxide and ZnO nanoparticles. Based on the magnetic property and size, the iron oxide nanoparticles were classified as superparamagnetic iron oxide nanoparticles (SPIONS) comprising a mixture of magnetite (Fe3-δO4) and maghemite (γ-Fe2O3). The role of reactive oxygen species (H2O2) and the involvement of the glycolytic pathway in the biosynthesis of the nanoparticles were confirmed using appropriate in vitro studies. The simplicity of treatment, the specificity of cells capable of synthesis of SPIONS, and the hyperthermia response observed in cancer cells indicate a promising strategy to achieve effective magnetic hyperthermia for cancer therapy.

15.
ACS Biomater Sci Eng ; 6(12): 6710-6725, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33320599

RESUMO

Repair of critical size bone defects is a clinical challenge that usually necessitates the use of bone substitutes. For successful bone repair, the substitute should possess osteoconductive, osteoinductive, and vascularization potential, with the ability to control post-implantation infection serving as an additional advantage. With an aim to develop one such substitute, we optimized a zinc-doped hydroxyapatite (HapZ) nanocomposite decorated on reduced graphene oxide (rGO), termed as G3HapZ, and demonstrated its potential to augment the bone repair. The biocompatible composite displayed its osteoconductive potential in biomineralization studies, and its osteoinductive property was confirmed by its ability to induce mesenchymal stem cell (MSC) differentiation to osteogenic lineage assessed by in vitro mineralization (Alizarin red staining) and expression of osteogenic markers including runt-related transcription factor 2 (RUNX-2), alkaline phosphatase (ALP), type 1 collagen (COL1), bone morphogenic protein-2 (BMP-2), osteocalcin (OCN), and osteopontin (OPN). While the potential of G3HapZ to support vascularization was displayed by its ability to induce endothelial cell migration, attachment, and proliferation, its antimicrobial activity was confirmed using S. aureus. Biocompatibility of G3HapZ was demonstrated by its ability to induce bone regeneration and neovascularization in vivo. These results suggest that G3HapZ nanocomposites can be exploited for a range of strategies in developing orthopedic bone grafts to accelerate bone regeneration.


Assuntos
Células-Tronco Mesenquimais , Nanocompostos , Óxido de Zinco , Proliferação de Células , Células Cultivadas , Durapatita , Grafite , Staphylococcus aureus , Zinco
16.
ACS Appl Mater Interfaces ; 12(18): 20912-20921, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32255604

RESUMO

This is the first report of exploiting the "quasi-spherical" shape of water molecules for recapitulating a true human extracellular matrix (ECM). Herein, water behaved as a quasi-spherical porogen, for engineering polysaccharide-rich and chemically defined 3D-microarchitecture, with semi-interpenetrating networks (S-IPNs). Furthermore, their viscoelastic behavior along with a heterogeneous, fibroporous morphology, facilitated instructive, self-remodeling of the bioartificial scaffolds, thence effectively permitting and promoting the growth of 3D tumor spheroids of divergent origins. The hybrid composites displayed reproducible, uniform tumor spheroids with a Z-depth of ∼65 ± 2 µm in case of human adenocarcinoma (DLD-1) and ∼54 ± 3 µm for human glioblastoma cells (U-251) (vs. nonuniform spheroids, on Agarose matrix). Thereafter, their capacity for anticancer drug screening was examined using limited cancer drugs. The conflicting drug screening results for Etoposide's reduced efficacy on glioblastoma cells cultured on our 3D matrix could be ascribed to decreased drug access and thus lower ingression. Nonetheless, adenocarcinoma's resistance to Camptothecin was paralleled. Moreover, their potential for real-time, high-content, phenotypic precision oncology was affirmed by the exceptional transparency of the synthesized composite. Since this 3D microarchitecture typifies ECM bioautomaton, this matrix can also be wielded for precision oncology.


Assuntos
Materiais Biomiméticos/química , Hidrogéis/química , Mananas/química , Esferoides Celulares/metabolismo , Alicerces Teciduais/química , Acrilatos/química , Antineoplásicos/farmacologia , Materiais Biomiméticos/síntese química , Camptotecina/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Etoposídeo/farmacologia , Matriz Extracelular/química , Humanos , Hidrogéis/síntese química , Metacrilatos/química , Polimerização , Porosidade , Reprodutibilidade dos Testes , Esferoides Celulares/efeitos dos fármacos , Engenharia Tecidual/métodos
17.
J Pharm Pharmacol ; 71(7): 1072-1081, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30957246

RESUMO

OBJECTIVE: Anti-neoplastic drug cisplatin is prescribed widely for treatment of a variety of malignancies. Its use has been restricted lately due to severe renal toxicity. The purpose of current study was to investigate the effect of pitavastatin (a hypolipidaemic drug) in cisplatin-induced acute kidney injury in rats. METHOD: Male Wistar rats (150-200 g) were treated with different doses of pitavastatin (0.16, 0.32 and 0.64 mg/kg per day p.o.; 10 days). On 7th day of the study, rats were administered cisplatin (8 mg/kg i.p.). Rats were euthanized (11th day), and blood and tissues were processed to evaluate biochemical, histopathological and ultrastructural parameters along with the analysis of immunohistochemistry and DNA-fragmentation studies. Protein expressions were analysed to demonstrate the underlying molecular mechanisms. KEY FINDINGS: In the study group with cisplatin insult, KFT parameters were found to be elevated, concentration of apoptotic markers was found to be increased, histopathological and ultramicroscopical architecture was found to be distorted and the expression of MAPK proteins was also found to be elevated as compared to the normal group rats. Pitavastatin treatment alleviated all these anomalies. CONCLUSION: Cisplatin-induced acute renal injury was improved on administration of pitavastatin via inhibition of MAPK and apoptotic pathway.


Assuntos
Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Cisplatino/efeitos adversos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Quinolinas/farmacologia , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Rim/metabolismo , Rim/patologia , Rim/ultraestrutura , Masculino , Ratos , Ratos Wistar
18.
Chem Biol Drug Des ; 94(1): 1352-1367, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31066219

RESUMO

Chromones are recognized as privileged structures and useful templates for the design of novel compounds with promising pharmacological activity. Several reports implicate chromone scaffold as an antitumor agent. The present study highlights synthesis, docking, and potential activity of isoxazolylchromones, 3(a-f), a new class of compounds as potential agents exhibiting ERα antagonism and ERß agonism. Molecular docking studies determined the binding site of compounds 3(a-f) in ERα and ERß. All the analogues synthesized showed preferential cytotoxicity in ERα+ cell line (MCF-7) compared to ERα- cell line (MDA-MB-231). Among the analogues synthesized, analogue 3d exhibited increased cytotoxicity. ERα silencing experiments confirmed the ERα selective nature of ligands. Transactivation assay on compound 3d indicated the down-regulation of ERα luciferase reporter gene expression and induction of ERß GFP in the treated cells. Cell cycle analysis revealed an increase in sub-G0/G1 population on treatment with analogue 3d as compared to control. Similar to tamoxifen, 3d-induced cell death is mediated through an increase in ROS as evidenced by change in roGFP ratio. Interestingly, the compound 3d induced mitochondrial trans-membrane potential loss and caspase activation without indication of autophagy compared to tamoxifen that induced autophagy in the treated cells. Lack of significant autophagy and induction of ERß signaling by the new compound place them as a better ERα antagonist.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cromonas/química , Receptor alfa de Estrogênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Autofagia/efeitos dos fármacos , Sítios de Ligação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromonas/metabolismo , Cromonas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/antagonistas & inibidores , Receptor beta de Estrogênio/metabolismo , Humanos , Isoxazóis/química , Ligantes , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia
19.
Nat Med ; 25(1): 111-118, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30478424

RESUMO

Although targeted therapies often elicit profound initial patient responses, these effects are transient due to residual disease leading to acquired resistance. How tumors transition between drug responsiveness, tolerance and resistance, especially in the absence of preexisting subclones, remains unclear. In epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma cells, we demonstrate that residual disease and acquired resistance in response to EGFR inhibitors requires Aurora kinase A (AURKA) activity. Nongenetic resistance through the activation of AURKA by its coactivator TPX2 emerges in response to chronic EGFR inhibition where it mitigates drug-induced apoptosis. Aurora kinase inhibitors suppress this adaptive survival program, increasing the magnitude and duration of EGFR inhibitor response in preclinical models. Treatment-induced activation of AURKA is associated with resistance to EGFR inhibitors in vitro, in vivo and in most individuals with EGFR-mutant lung adenocarcinoma. These findings delineate a molecular path whereby drug resistance emerges from drug-tolerant cells and unveils a synthetic lethal strategy for enhancing responses to EGFR inhibitors by suppressing AURKA-driven residual disease and acquired resistance.


Assuntos
Aurora Quinase A/metabolismo , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Contagem de Células , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação/genética , Neoplasia Residual/tratamento farmacológico , Proteínas Nucleares/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia
20.
Cell Syst ; 7(5): 526-536.e6, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30414925

RESUMO

Leveraging insights from genomic studies of patient tumors is limited by the discordance between these tumors and the cell line models used for functional studies. We integrate omics datasets using functional networks to identify gene modules reflecting variation between tumors and show that the structure of these modules can be evaluated in cell lines to discover clinically relevant biomarkers of therapeutic responses. Applied to breast cancer, we identify 219 gene modules that capture recurrent alterations and subtype patients and quantitate various cell types within the tumor microenvironment. Comparison of modules between tumors and cell lines reveals that many modules composed primarily of gene expression and methylation are poorly preserved. In contrast, preserved modules are highly predictive of drug responses in a manner that is robust and clinically relevant. This work addresses a fundamental challenge in pharmacogenomics that can only be overcome by the joint analysis of patient and cell line data.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genômica/métodos , Farmacogenética/métodos , Biomarcadores Tumorais , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Humanos
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