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1.
J Med Virol ; 95(7): e28965, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37488710

RESUMO

The distinct disease progression patterns of severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2) indicate diverse host immune responses. SARS-CoV-2 severely impairs type I interferon (IFN) cell signaling, resulting in uncontrolled late-phase lung damage in patients. For better pharmacological properties, cytokine modifications may sometimes result in a loss of biological activity against the virus. Here, we employed the genetic code expansion and engineered IFN-ß, a phase II clinical cytokine with 3-amino tyrosine (IFN-ß-A) that reactivates STAT2 expression in virus-infected human cells through JAK/STAT cell signaling without affecting signal activation and serum half-life. This study identified that genetically encoded IFN-ß-A might stabilize the protein-receptor complex and trigger JAK-STAT cell signaling, which is a promising modality for controlling SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Membrana Celular , Citocinas , Progressão da Doença
2.
Exp Mol Pathol ; 128: 104821, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35908616

RESUMO

BACKGROUND: Plasma leakage is a major pathogenic manifestation of severe dengue and is a precursor of life-threatening complications associated with dengue. Accumulating evidence indicates the role of Matrix Metalloproteinases (MMPs) in mediating vascular permeability and plasma leakage following induction by the dengue virus. This study aims to investigate the utility of MMP-2, MMP-3, and MMP-9 in predicting the severity of dengue infection and further explore the relationship of these markers with the pathogenic factors associated with plasma leakage. METHODS: The dengue-positive subjects were classified into mild and severe dengue groups based on the manifestation of warning signs. The samples in each group and healthy controls were quantified for basic laboratory characteristics. The levels of MMP-2, MMP-3, MMP-9, and Macrophage migration inhibitory factor (MIF) were estimated in all serum samples using a multiplex bead-based assay. RESULTS: MMP-2 and MMP-9 were markedly elevated in severe dengue patients compared to mild dengue patients and healthy controls. No alteration in the circulating levels of MMP-3 was observed between the study groups. ROC curve analysis indicated that MMP-2 and MMP-9 exhibited good potential for predicting severe dengue. Notably, an increase in MMP-9 was associated with increased MIF and Hematocrit levels in severe dengue patients. CONCLUSION: MMP-2 and MMP-9 could serve as prognostic biomarkers for severe dengue. These findings also identify the association of MMP-9 with markers of plasma leakage, thereby encouraging further studies to explore the therapeutic potential of targeting MMP-9 in managing plasma leakage in severe dengue.


Assuntos
Vírus da Dengue , Dengue , Fatores Inibidores da Migração de Macrófagos , Dengue Grave , Humanos , Dengue Grave/complicações , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Metaloproteinase 3 da Matriz , Prognóstico , Biomarcadores , Dengue/diagnóstico , Dengue/etiologia
3.
Microb Pathog ; 135: 103612, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31252064

RESUMO

Emergence of antibiotic resistant bacteria has necessitated the drive to explore competent antimicrobial agents or to develop novel formulations to treat infections including Aeromonas hydrophila. The present study investigates the synergistic antibacterial effects of citrus flavonoid rutin and florfenicol (FF) against A. hydrophila in vitro and in vivo. Rutin is extracted and purified from Citrus sinensis peel through preparative HPLC and characterized through TLC, GC-MS and 1H and 13C NMR analyses. Though rutin did not display significant antibacterial activity, it modulated FF activity resulting in four-fold reduction in the MIC value for FF. The anti-biofilm potential of synergistic association of rutin and FF was validated by protein analysis, quantification of exopolysaccharide (EPS) and microscopy studies using sub-MIC doses. Besides antibacterial action, in vivo studies showed that Rutin/FF combination enhanced host immunity by improving blood cell count, anti-protease, and lysozyme activities as well as decreased the oxidative stress and the pathological changes of tilapia Oreochromis niloticus against A. hydrophila infection. No significant DNA damages or clastogenic effects were detected in tilapia challenged with A. hydrophila under Rutin/FF treatment. It is shown that an acute-phase Lipopolysaccharide binding protein (LBP) enhances the innate host defence against bacterial challenge. Semi quantitative RT-PCR and western blot results revealed the significant increase of LBP in the supernatant of tilapia monocytes/macrophages challenged with A. hydrophila upon treatment. The study findings substantiate that the combination of natural molecules with antibiotics may open up possibilities to treat MDR strains.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/veterinária , Rutina/farmacologia , Rutina/uso terapêutico , Tianfenicol/análogos & derivados , Aeromonas hydrophila/crescimento & desenvolvimento , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Citrus sinensis/química , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Combinação de Medicamentos , Sinergismo Farmacológico , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/patologia , Pesqueiros , Imunidade/efeitos dos fármacos , Imunomodulação , Índia , Testes de Sensibilidade Microbiana , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rutina/imunologia , Tianfenicol/imunologia , Tianfenicol/farmacologia , Tianfenicol/uso terapêutico , Tilápia/microbiologia , Virulência/efeitos dos fármacos
4.
J Glob Infect Dis ; 15(2): 43-51, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469462

RESUMO

Introduction: Prolonged COVID-19 pandemic accelerates the emergence and transmissibility of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants through the accumulation of adaptive mutations. Particularly, adaptive mutations in spike (S) protein of SARS-CoV-2 leads to increased viral infectivity, severe morbidity and mortality, and immune evasion. This study focuses on the phylodynamic distribution of SARS-CoV-2 variants during the year 2021 in India besides analyzing the functional significance of mutations in S-protein of SARS-CoV-2 variants. Methods: Whole genome of SARS-CoV-2 sequences (n = 87957) from the various parts of India over the period of January to December 2021 was retrieved from Global Initiative on Sharing All Influenza Data. All the S-protein sequences were subjected to clade analysis, variant calling, protein stability, immune escape potential, structural divergence, Furin cleavage efficiency, and phylogenetic analysis using various in silico tools. Results: Delta variant belonging to 21A, 21I, and 21J clades was found to be predominant throughout the year 2021 though many variants were also present. A total of 4639 amino acid mutations were found in S-protein. D614G was the most predominant mutation in the S-protein followed by P681R, L452R, T19R, T478K, and D950N. The highest number of mutations was found in the N-terminal domain of S-protein. Mutations in the crucial sites of S-protein impacting pathogenicity, immunogenicity, and fusogenicity were identified. Intralineage diversity analysis showed that certain variants of SARS-CoV-2 possess high diversification. Conclusions: The study has disclosed the distribution of various variants including the Delta, the predominant variant, in India throughout the year 2021. The study has identified mutations in S-protein of each SARS-CoV-2 variant that can significantly impact the virulence, immune evasion, increased transmissibility, high morbidity, and mortality. In addition, it is found that mutations acquired during each viral replication cycle introduce new sub-lineages as studied by intralineage diversity analysis.

5.
J Glob Infect Dis ; 15(2): 52-58, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469472

RESUMO

Introduction: Establishing the etiological cause of acute encephalitis syndrome (AES) is challenging due to the distinct distribution of various etiological agents. This study aims to determine the etiological profiles of both viruses and bacteria and their associated clinico-epidemiological features among the AES suspected cases in Tamil Nadu, India. Methods: Samples of 5136 suspected AES cases from January 2016 to December 2020 (5 years) were subjected to the detection of etiological agents for AES through serological and molecular diagnosis methods. Further, the clinical profile, age- and gender-wise susceptibility of cases, co-infection with other AES etiological agents, and seasonality pattern with respect to various etiological agents were examined. Results: AES positivity was established in 1480 cases (28.82%) among the 5136 suspected cases and the positivity for male and female groups were 57.77% and 42.23%, respectively. The pediatric group was found to be more susceptible than others. Among the etiological agents tested, the Japanese encephalitis virus (JEV) was the predominant followed by Cytomegalovirus, Herpes Simplex virus, Epstein-Barr virus, Varicella Zoster virus, and others. Co-infection with other AES etiological agents was observed in 3.5% of AES-positive cases. Seasonality was observed only for vector-borne diseases such as JEV, dengue virus, and West Nile virus infections in this study. Conclusion: AES was found to be a significant burden for Tamil Nadu with a diverse etiological spectrum including both sporadic and outbreak forms. Overlapping clinical manifestations of AES agents necessitate the development of region-specific diagnostic algorithm with distinct etiological profiles for early detection and effective case management.

6.
Immunobiology ; 227(6): 152289, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36257203

RESUMO

BACKGROUND: Severe dengue is associated with a considerable risk of mortality, and there is currently a lack of appropriate prognostic biomarkers to predict its severity. Pathogenesis of severe dengue is characterized by overt inflammation, endothelial activation, and increased vascular permeability. The current study investigates the utility of endothelial, inflammatory, and vascular permeability factors as biomarkers to identify dengue severity, which could improve disease prognosis and management. METHODS: The dengue-positive subjects were classified based on seropositivity for NS1, IgM, and IgG. The samples in each group were quantified for basic clinical investigations. The levels of Interleukin-6 (IL-6), Tumor necrosis factor receptor 1 (TNFR1), EOTAXIN, Monocyte chemoattractant protein-1 (MCP-1), Monokine induced by interferon-gamma (MIG), Intercellular adhesion molecule-1 (ICAM-1), Vascular cell adhesion molecule-1 (VCAM-1), Thrombomodulin, and Angiopoietin-2 were estimated in all serum samples using the multiplex bead-based assay. RESULTS: IgG seropositive dengue patients showed abnormal laboratory characteristics and severe dengue symptoms. Among the studied markers, only IL-6, TNFR1, ICAM-1, VCAM-1, Thrombomodulin, and Angiopoietin-2 were significantly elevated in IgG seropositive patients compared to healthy controls. Increased IL-6 and TNFR1 levels were associated with decreased platelet count and elevated Hematocrit levels in IgG seropositive patients. Furthermore, ROC curve analysis indicated that IL-6, TNFR1, Thrombomodulin, and Angiopoietin-2 showed good potential for predicting dengue severity. CONCLUSION: Inflammatory markers IL-6 and TNFR1, and endothelial factors Angiopoietin-2 and Thrombomodulin, could serve as prognostic markers for severe dengue. These findings also encourage the future study of these biomarkers in the pathogenesis of severe dengue infection.


Assuntos
Dengue , Dengue Grave , Humanos , Dengue Grave/diagnóstico , Molécula 1 de Adesão Intercelular , Angiopoietina-2 , Molécula 1 de Adesão de Célula Vascular , Trombomodulina , Receptores Tipo I de Fatores de Necrose Tumoral , Interleucina-6 , Prognóstico , Biomarcadores , Imunoglobulina G , Dengue/diagnóstico
7.
J Glob Infect Dis ; 13(4): 164-171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35017872

RESUMO

INTRODUCTION: The COVID-19 pandemic is associated with high morbidity and mortality, with the emergence of numerous variants. The dynamics of SARS-CoV-2 with respect to clade distribution is uneven, unpredictable and fast changing. METHODS: Retrieving the complete genomes of SARS-CoV-2 from India and subjecting them to analysis on phylogenetic clade diversity, Spike (S) protein mutations and their functional consequences such as immune escape features and impact on infectivity. Whole genome of SARS-CoV-2 isolates (n = 4,326) deposited from India during the period from January 2020 to December 2020 is retrieved from Global Initiative on Sharing All Influenza Data (GISAID) and various analyses performed using in silico tools. RESULTS: Notable clade dynamicity is observed indicating the emergence of diverse SARS-CoV-2 variants across the country. GR clade is predominant over the other clades and the distribution pattern of clades is uneven. D614G is the commonest and predominant mutation found among the S-protein followed by L54F. Mutation score prediction analyses reveal that there are several mutations in S-protein including the RBD and NTD regions that can influence the virulence of virus. Besides, mutations having immune escape features as well as impacting the immunogenicity and virulence through changes in the glycosylation patterns are identified. CONCLUSIONS: The study has revealed emergence of variants with shifting of clade dynamics within a year in India. It is shown uneven distribution of clades across the nation requiring timely deposition of SARS-CoV-2 sequences. Functional evaluation of mutations in S-protein reveals their significance in virulence, immune escape features and disease severity besides impacting therapeutics and prophylaxis.

8.
ACS Appl Bio Mater ; 3(1): 385-399, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35019455

RESUMO

Controlling biofilms of bacteria is a challenging aspect because of their drug-resistance potentials against a range of antibiotics, demanding the development of active anti-biofilm agents. Rutin (R), a natural antioxidant, and benzamide (B), a synthetic antibacterial agent, have several pharmacological and antibacterial abilities. Herein, we developed PEG-PLGA NPs that synergistically carried rutin and benzamide as drug candidates, while displaying therapeutic and anti-biofilm  functions. These drug delivery NPs were synthesized by the oil-in-water emulsion (O/W) solvent evaporation technique. The obtained NPs were characterized by UV-vis, FT-IR, SEM, TEM, and DLS measurements. Confocal laser scanning microscopy was employed to evaluate the anti-biofilm capabilities against Staphylococcus aureus and Pseudomonas aeruginosa and further quantified the levels of residual biofilm constituents such as protein and exopolysaccharide (EPS). Drug release experiments showed the controlled release of rutin-benzamide (RB) for several days. Antibacterial analyses showed that the minimum inhibitory concentration (MIC) of NPs was at least two times lower than that of the free drugs. RB-PEG-PLGA NPs revealed that they targeted biofilm-forming bacteria through the disruption of the membrane and biofilm surface and were observed to be nontoxic when tested using human erythrocytes and human cell lines. In vivo evaluations in zebrafish showed that the NPs did not alter the antioxidant functions and histological features of tissues. On the basis of results obtained, it is substantiated that the rutin-benzamide-loaded nanocarrier offers potential anti-biofilm therapy due to its high anti-biofilm activity and biocompatibility.

9.
Int J Biol Macromol ; 140: 808-824, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31437502

RESUMO

Spirograph is a geometric drawing that produces mathematical roulette curves of the variety technically known as hypotrochoids and epitrochoids. This paper presents a research on a novel Spirograph Based Mechanical System (SBMS) meant for the production of electrospun mat with near uniform characteristics for wound dressing applications. A combination of natural (Chitosan) and artificial (Polyethylene oxide) polymer, along with Aloe vera plant extract has been evaluated as a material for wound dressing application. The improvement in the mechanical property, in vitro and in vivo studies indicate developed SBMS compared to the typical collectors has been found suitable for producing electrospun mat for wound dressing applications.


Assuntos
Aloe/química , Materiais Biocompatíveis/química , Quitosana/química , Polietilenoglicóis/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Linhagem Celular , Colágeno , Feminino , Camundongos , Testes de Sensibilidade Microbiana , Análise Espectral , Resistência à Tração , Cicatrização
10.
Mater Sci Eng C Mater Biol Appl ; 103: 109716, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349431

RESUMO

Improved therapeutic effects can be achieved by the delivery of combination of drugs through multifunctional cell targeted nanocarrier systems. The present investigation reports the preparation of Poly (D,L-lactic-co-glycolic acid) (PLGA) nanospheres loaded with the novel combination such as Rutin (R) and Benzamide (B) as drugs using water-oil-water (w/o/w) emulsion method. Dual drug loaded PLGA nanospheres (R/B@PLGA) were stabilized by poly (vinyl alcohol) (PVA) coating and characterized in terms of morphology, size, surface charge, and structural chemistry by Scanning electron microscopy (SEM), Dynamic light scattering (DLS), Zeta potential analysis, UV-vis and Fourier transform infrared (FT-IR) spectroscopy. The inhibitory effects of rutin and benzamide on MDA-MB-231 (triple negative breast cancer-TNBC) cells using the drug loaded PLGA nanospheres as well as their non-toxic features were evaluated in vivo. The anticancer activity of the R/B@PLGA nanospheres through cell cycle disruption and apoptotic induction was assessed in vitro by flow cytometry analysis. Further, the in vitro antioxidant capacity, pH-based drug release and hemocompatible property were also investigated. It was shown that the R/B@PLGA nanospheres lacked genotoxic potential and they did not alter the antioxidant enzyme activities and histological features of zebrafish. Hence, this dual drug delivery system (DDS) not only actively targets multidrug-resistance (MDR) associated phenotype but also improves the therapeutic efficiency by its non-toxic nature towards enhanced cancer cell focused delivery and sustained release of therapeutic agents.


Assuntos
Benzamidas , Portadores de Fármacos , Nanosferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Rutina , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Benzamidas/química , Benzamidas/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Feminino , Humanos , Nanosferas/química , Nanosferas/uso terapêutico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Rutina/química , Rutina/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Peixe-Zebra
11.
Biomed Pharmacother ; 109: 1181-1195, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30551368

RESUMO

Recent studies on flavonoids forming complexes with macromolecules attract researchers due to their enhanced bioavailability as well as chemo-preventive efficacy. In this study, a flavonoid rutin (Ru) is non-covalently complexed with fucoidan (Fu) using the functional groups to obtain a therapeutic polymeric complex overcoming the limitations of bioavailability of rutin. The prepared novel rutin-fucoidan (Ru-Fu) complex is characterized for spectroscopic features, particle size and distribution analysis by DLS. It is shown that the complex displayed the nanostructural features that are different from that of the usual rutin-fucoidan mixture. The studies on drug release profiles at different pH (5.5, 6.8 and 7.4) show that the sustained release of compounds from complex occurs preferentially at the desired endosomal pH (5.5). Further, the chemopreventive potential of Ru-Fu complex is investigated against HeLa cells by cellular apoptotic assays and flow cytometric analysis. It showed that the complex is able to disrupt cell cycle regulation and has the ability to induce cellular apoptosis via nuclear fragmentation, ROS generation and mitochondrial potential loss. In vitro cell viability assay with Ru-Fu complex shows that the complex is biocompatible on normal cells. The hemolysis assay also reveals that the complex does not release hemoglobin from human red blood cells (RBCs). Thus, the study is envisaged to open up interests for developing such formulations against cervical cancer and other cancers.


Assuntos
Apoptose/efeitos dos fármacos , Polissacarídeos/farmacologia , Rutina/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Disponibilidade Biológica , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Flavonoides/farmacologia , Células HeLa , Humanos , Mitocôndrias/efeitos dos fármacos , Fitoterapia/métodos
12.
Int J Biol Macromol ; 106: 1032-1040, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28843674

RESUMO

Collagen is a unique protein abundantly present in the connective tissues of mammals and widely used for biomaterial preparation. In this study, we synthesized and characterized collagen-fucoidan blend films for tissue regenerative properties. Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) were used for thermal analysis of the blend films, and the films exhibited higher thermal stability and denaturation temperature (Td) than those of native collagen due to intramolecular hydrogen bonding interaction between collagen and fucoidan, which was analyzed by FTIR spectroscopy. Morphological evaluation of these films using Scanning Electron Microscopy (SEM) showed smaller pore size than the control. Moreover, fucoidan protects collagen against enzymatic degradation and thereby increases the structural stability of collagen. Further, the in vitro studies of the synthesized films showed that they effectively facilitated the proliferation and migration of fibroblast cells without exhibiting toxicity. These study results suggested that the collagen-fucoidan blend films are a favorable substrate for growth of fibroblast cells, and may have great potential for tissue engineering applications.


Assuntos
Proliferação de Células/efeitos dos fármacos , Colágeno/química , Polissacarídeos/química , Medicina Regenerativa , Varredura Diferencial de Calorimetria , Quitosana/química , Colágeno/farmacologia , Fibroblastos/efeitos dos fármacos , Humanos , Ligação de Hidrogênio/efeitos dos fármacos , Teste de Materiais , Polissacarídeos/farmacologia , Resistência à Tração , Engenharia Tecidual
13.
J Glob Infect Dis ; 10(2): 99-107, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910571

RESUMO

BACKGROUND: Deformities and neuropathic chronic ulcers are the common features associated with leprosy-cured individuals that impact their quality of life and impair rehabilitation efforts. The challenging aspects for treatment of chronic wounds are the factors that inhibit healing. We reasoned that limited success of various therapeutic interventions could be due to the fact that leprosy-cured individual's physiology gets acclimatized to having a chronic wound that any therapeutic intervention is counterbalanced to maintain status quo at the wound site. Therefore, an alternative strategy would be to use biomaterials that gradually alter the wound site allowing the individual's physiology to participate in the healing process. AIMS: Developing the human amnion (Amn)-derived biomaterial scaffolds and evaluating its use to heal chronic wounds in leprosy-cured but deformed persons (LCDPs). MATERIALS AND METHODS: Using an enzymatic protocol, we have developed a rapid method to generate biomaterial scaffolds from discarded human Amn. A clinical trial on 26 LCDPs was performed with the biomaterial, and its wound-healing potential was then compared with LCDPs undergoing standard treatment procedure. RESULTS: Biomaterial-based treatment of chronic wounds on LCDP displayed a higher efficiency in healing when compared to standard treatment. CONCLUSIONS: This study exemplifies that biomaterial-based treatment of leprosy-wounds offers an excellent affordable alternative for wound management. This study underlines the importance of involving both local wound environment and systemic effects for healing. In addition, we highlight wound healing as a necessity for successful rehabilitation and reintegration of leprosy-cured person into the society.

14.
J Nutr Biochem ; 44: 11-21, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28343084

RESUMO

Nrf2 (nuclear factor erythroid 2-related factor-2) is a transcription factor that regulates oxidative/xenobiotic stress response and also suppress inflammation. Nrf2 signaling is associated with an increased susceptibility to various kinds of stress. Nrf2 has been shown as a promising therapeutic target in various human diseases including diabetes. Our earlier studies showed Pterostilbene (PTS) as a potent Nrf2 activator, and it protects the pancreatic ß-cells against oxidative stress. In this study, we investigated PTS confer protection against cytokine-induced ß-cell apoptosis and its role on insulin secretion in streptozotocin (STZ)-induced diabetic mice. The Nrf2 activation potential of PTS was assessed by dissociation of the Nrf2-Keap1 complex and by expression of ARE-driven downstream target genes in MIN6 cells. Further, the nuclear Nrf2 translocation and blockage of apoptotic signaling as demonstrated by the reduction of BAX/Bcl-2 ratio, Annexin-V positive cells and caspase-3 activity conferred the cyto-protection of PTS against cytokine-induced cellular damage. In addition, PTS treatment markedly improved glucose homeostasis and abated inflammatory response evidenced by the reduction of proinflammatory cytokines in diabetic mice. The inhibition of ß-cell apoptosis by PTS as assessed by BAX/Bcl-2 ratio and caspase-3 activity in the pancreas was associated with the activation of Nrf2 and the expression of its downstream target genes. PTS also inhibited the activation of iNOS and decreased nitric oxide (NO) formation in the pancreas of diabetic animals. The results obtained from both in vitro and in vivo experiments showed that PTS improves ß-cell function and survival against cytokine stress and also prevents STZ-induced diabetes.


Assuntos
Células Secretoras de Insulina/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Estilbenos/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Glicemia/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
15.
Front Pharmacol ; 8: 433, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769790

RESUMO

The potential of multifunctional wound heal biomaterial relies on the optimal content of therapeutic constituents as well as the desirable physical, chemical, and biological properties to accelerate the healing process. Formulating biomaterials such as amnion or collagen based scaffolds with natural products offer an affordable strategy to develop dressing material with high efficiency in healing wounds. Using image based phenotyping and quantification, we screened natural product derived bioactive compounds for modulators of types I and III collagen production from human foreskin derived fibroblast cells. The identified hit was then formulated with amnion to develop a biomaterial, and its biophysical properties, in vitro and in vivo effects were characterized. In addition, we performed functional profiling analyses by PCR array to understand the effect of individual components of these materials on various genes such as inflammatory mediators including chemokines and cytokines, growth factors, fibroblast stimulating markers for collagen secretion, matrix metalloproteinases, etc., associated with wound healing. FACS based cell cycle analyses were carried out to evaluate the potential of biomaterials for induction of proliferation of fibroblasts. Western blot analyses was done to examine the effect of biomaterial on collagen synthesis by cells and compared to cells grown in the presence of growth factors. This work demonstrated an uncomplicated way of identifying components that synergistically promote healing. Besides, we demonstrated that modulating local wound environment using biomaterials with bioactive compounds could enhance healing. This study finds that the developed biomaterials offer immense scope for healing wounds by means of their skin regenerative features such as anti-inflammatory, fibroblast stimulation for collagen secretion as well as inhibition of enzymes and markers impeding the healing, hydrodynamic properties complemented with other features including non-toxicity, biocompatibility, and safety.

16.
Eur J Pharmacol ; 777: 9-16, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26921755

RESUMO

Nuclear factor erythroid 2-related factor (Nrf2), a key transcription factor triggers the expression of antioxidant and detoxification genes thereby providing cellular protective functions against oxidative stress-mediated disorders. Recent research has identified that pharmacological activation of Nrf2 also regulates the largest cluster of genes associated with lipid metabolism. With this background, this paper highlights the anti-hyperlipidemic and anti-peroxidative role of pterostilbene (PTS), an Nrf2 activator, in streptozotocin (STZ)-induced diabetic model. PTS administration to diabetic mice for 5 weeks significantly regulated blood glucose levels through the elevation of insulin secretion. The circulatory and liver lipid profiles of total cholesterol (TC), triglycerides (TG) and non-esterified fatty acids (NEFA) were maintained to normal levels upon PTS treatment. Moreover, PTS administration also normalized the circulatory levels of very low-, low- and high density lipoprotein cholesterols (VLDL-, LDL-, HDL-C) and also reduced lipid peroxidation in STZ-induced diabetic mice. In addition, Nrf2 and its downstream targets, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) enzyme activities and glutathione (GSH) levels were significantly elevated in liver tissues of diabetic mice upon PTS administration. Further, H&E staining of diabetic mouse liver showed collapse in hepatic microvesicles due to altered lipid metabolism. Both structural and functional alterations were attenuated by PTS indicating its role in diabetic dyslipidemia through Nrf2-mediated mechanism that could be considered as a promising therapeutic agent.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Hipoglicemiantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Lipoproteínas/sangue , Lipoproteínas/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Estilbenos/uso terapêutico
17.
Sci Rep ; 6: 34053, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27725731

RESUMO

Combination therapy of multiple drugs through a single system is exhibiting high therapeutic effects. We investigate nanocarrier mediated inhibitory effects of topotecan (TPT) and quercetin (QT) on triple negative breast cancer (TNBC) (MDA-MB-231) and multi drug resistant (MDR) type breast cancer cells (MCF-7) with respect to cellular uptake efficiency and therapeutic mechanisms as in vitro and in vivo. The synthesized mesoporous silica nanoparticle (MSN) pores used for loading TPT; the outer of the nanoparticles was decorated with poly (acrylic acid) (PAA)-Chitosan (CS) as anionic inner-cationic outer layer respectively and conjugated with QT. Subsequently, grafting of arginine-glycine-aspartic acid (cRGD) peptide on the surface of nanocarrier (CPMSN) thwarted the uptake by normal cells, but facilitated their uptake in cancer cells through integrin receptor mediated endocytosis and the dissociation of nanocarriers due to the ability to degrade of CS and PAA in acidic pH, which enhance the intracellular release of drugs. Subsequently, the released drugs induce remarkable molecular activation as well as structural changes in tumor cell endoplasmic reticulum, nucleus and mitochondria that can trigger cell death. The valuable CPMSNs may open up new avenues in developing targeted therapeutic strategies to treat cancer through serving as an effective drug delivery podium.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Portadores de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Quitosana/química , Quitosana/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Feminino , Humanos , Células MCF-7 , Nanopartículas/química , Nanopartículas/uso terapêutico , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Quercetina/química , Quercetina/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Topotecan/química , Topotecan/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
18.
ACS Appl Mater Interfaces ; 8(3): 2262-79, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26771508

RESUMO

Multifunctional magnetic polymer nanocombinations are gaining importance in cancer nanotheranostics due to their safety and their potential in delivering targeted functions. Herein, we report a novel multifunctional core-shell magnetic polymer therapeutic nanocomposites (NCs) exhibiting pH dependent "Off-On" release of drug against breast cancer cells. The NCs are intact in blood circulation ("Off" state), i.e., at physiological pH, whereas activated ("On" state) at intracellular acidic pH environment of the targeted breast cancer cells. The NCs are prepared by coating the cannonball (iron nanocore) with hydrophobic nanopockets of pH-responsive poly(d,l-lactic-co-glycolic acid) (PLGA) polymer nanoshell that allows efficient loading of therapeutics. Further, the nanocore-polymer shell is stabilized by poly(vinylpyrrolidone) (PVP) and functionalized with a targeting HER2 ligand. The prepared Her-Fe3O4@PLGA-PVP nanocomposites facilitate packing of anticancer drug (Tamoxifen) without premature release in the bloodstream, recognizing the target cells through binding of Herceptin antibody to HER2, a cell surface receptor expressed by breast cancer cells to promote HER2 receptor mediated endocytosis and finally releasing the drug at the intracellular site of tumor cells ("On" state) to induce apoptosis. The therapeutic efficiency of hemo/cytocompatible NCs drug delivery system (DDS) in terms of targeted delivery and sustained release of therapeutic agent against breast cancer cells was substantiated by in vitro and in vivo studies. The multifunctional properties of Her-Tam-Fe3O4@PLGA-PVP NCs may open up new avenues in cancer therapy through overcoming the limitations of conventional cancer therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Fenômenos Magnéticos , Terapia de Alvo Molecular , Nanocompostos/química , Polímeros/química , Receptor ErbB-2/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
19.
Colloids Surf B Biointerfaces ; 125: 65-72, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25437065

RESUMO

Matrix metalloproteinases (MMPs) have been investigated as a potential target for treating invasive breast cancers. The chemotherapy for breast cancer is often prescribed as a combination of drugs. The present study investigates a novel strategy of combining a MMP inhibitor, Epigallocatechin gallate (EGCG), along with an anticancer drug, Paclitaxel (PTX), in the form of a liposomal co-delivery system. The developed PTX/EGCG co-loaded liposomes showed an entrapment of 77.11±2.30% and 59.11±3.51% for PTX and EGCG, respectively. The in vitro efficacy of the liposomes was assessed by their ability to promote apoptosis and curtail cell invasion. On all parameters, namely cytotoxicity and caspase-3 activity that are indicators of apoptosis, and MMP-2 and - 9 inhibition and invasion assays that are indicators of cell invasion, the PTX/EGCG co-loaded liposomes showed better results than each of the individual drug loaded liposomes. These findings demonstrate the synergistic outcome of PTX/EGCG combination and indicate the suitability of PTX/EGCG co-loaded liposomes for the treatment of invasive breast cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Catequina/análogos & derivados , Lipossomos/química , Glândulas Mamárias Humanas/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/farmacologia , Paclitaxel/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Catequina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Composição de Medicamentos , Sinergismo Farmacológico , Feminino , Expressão Gênica , Humanos , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo
20.
Asian Pac J Trop Med ; 8(5): 352-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26003593

RESUMO

OBJECTIVE: To obtain luteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon (L.) (C. dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells. METHODS: The ethanolic extract of C. dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus (CHIKV) fraction. Reverse phase-HPLC and GC-MS studies were carried out to identify the major phytochemicals in the fraction using phytochemical standards. Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells. Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) after treating the viral infected Vero cells with the fraction. RESULTS: Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids, luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C. dactylon. The fraction was found to exhibit potent viral inhibitory activity (about 98%) at the concentration of 50 µg/mL as observed by reduction in cytopathic effect, and the cytotoxic concentration of the fraction was found to be 250 µg/mL. RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells. CONCLUSIONS: Luteolin and apigenin rich ethanolic fraction from C. dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus.

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