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1.
J Glob Infect Dis ; 15(2): 43-51, 2023.
Article in English | MEDLINE | ID: mdl-37469462

ABSTRACT

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.

2.
J Glob Infect Dis ; 15(2): 52-58, 2023.
Article in English | MEDLINE | ID: mdl-37469472

ABSTRACT

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.

3.
J Med Virol ; 95(7): e28965, 2023 07.
Article in English | MEDLINE | ID: mdl-37488710

ABSTRACT

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.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Cell Membrane , Cytokines , Disease Progression
4.
Immunobiology ; 227(6): 152289, 2022 11.
Article in English | MEDLINE | ID: mdl-36257203

ABSTRACT

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.


Subject(s)
Dengue , Severe Dengue , Humans , Severe Dengue/diagnosis , Intercellular Adhesion Molecule-1 , Angiopoietin-2 , Vascular Cell Adhesion Molecule-1 , Thrombomodulin , Receptors, Tumor Necrosis Factor, Type I , Interleukin-6 , Prognosis , Biomarkers , Immunoglobulin G , Dengue/diagnosis
5.
Exp Mol Pathol ; 128: 104821, 2022 10.
Article in English | MEDLINE | ID: mdl-35908616

ABSTRACT

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.


Subject(s)
Dengue Virus , Dengue , Macrophage Migration-Inhibitory Factors , Severe Dengue , Humans , Severe Dengue/complications , Matrix Metalloproteinase 2 , Matrix Metalloproteinase 9 , Matrix Metalloproteinase 3 , Prognosis , Biomarkers , Dengue/diagnosis , Dengue/etiology
6.
J Glob Infect Dis ; 13(4): 164-171, 2021.
Article in English | MEDLINE | ID: mdl-35017872

ABSTRACT

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.

7.
ACS Appl Bio Mater ; 3(1): 385-399, 2020 Jan 21.
Article in English | MEDLINE | ID: mdl-35019455

ABSTRACT

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.

8.
Int J Biol Macromol ; 140: 808-824, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31437502

ABSTRACT

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.


Subject(s)
Aloe/chemistry , Biocompatible Materials/chemistry , Chitosan/chemistry , Polyethylene Glycols/chemistry , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Cell Line , Collagen , Female , Mice , Microbial Sensitivity Tests , Spectrum Analysis , Tensile Strength , Wound Healing
9.
Mater Sci Eng C Mater Biol Appl ; 103: 109716, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31349431

ABSTRACT

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.


Subject(s)
Benzamides , Drug Carriers , Nanospheres , Polylactic Acid-Polyglycolic Acid Copolymer , Rutin , Triple Negative Breast Neoplasms/drug therapy , Animals , Apoptosis/drug effects , Benzamides/chemistry , Benzamides/pharmacology , Cell Cycle/drug effects , Cell Line, Tumor , Drug Carriers/chemistry , Drug Carriers/pharmacology , Female , Humans , Nanospheres/chemistry , Nanospheres/therapeutic use , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/pharmacology , Rutin/chemistry , Rutin/pharmacology , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Zebrafish
10.
Microb Pathog ; 135: 103612, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31252064

ABSTRACT

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.


Subject(s)
Aeromonas hydrophila/drug effects , Fish Diseases/drug therapy , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/veterinary , Rutin/pharmacology , Rutin/therapeutic use , Thiamphenicol/analogs & derivatives , Aeromonas hydrophila/growth & development , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Biofilms/drug effects , Citrus sinensis/chemistry , DNA Damage/drug effects , Disease Models, Animal , Drug Combinations , Drug Synergism , Fish Diseases/immunology , Fish Diseases/microbiology , Fish Diseases/pathology , Fisheries , Immunity/drug effects , Immunomodulation , India , Microbial Sensitivity Tests , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Rutin/immunology , Thiamphenicol/immunology , Thiamphenicol/pharmacology , Thiamphenicol/therapeutic use , Tilapia/microbiology , Virulence/drug effects
11.
Biomed Pharmacother ; 109: 1181-1195, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30551368

ABSTRACT

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.


Subject(s)
Apoptosis/drug effects , Polysaccharides/pharmacology , Rutin/pharmacology , Uterine Cervical Neoplasms/drug therapy , Biological Availability , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Female , Flavonoids/pharmacology , HeLa Cells , Humans , Mitochondria/drug effects , Phytotherapy/methods
12.
J Glob Infect Dis ; 10(2): 99-107, 2018.
Article in English | MEDLINE | ID: mdl-29910571

ABSTRACT

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.

13.
Int J Biol Macromol ; 106: 1032-1040, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28843674

ABSTRACT

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.


Subject(s)
Cell Proliferation/drug effects , Collagen/chemistry , Polysaccharides/chemistry , Regenerative Medicine , Calorimetry, Differential Scanning , Chitosan/chemistry , Collagen/pharmacology , Fibroblasts/drug effects , Humans , Hydrogen Bonding/drug effects , Materials Testing , Polysaccharides/pharmacology , Tensile Strength , Tissue Engineering
14.
Front Pharmacol ; 8: 433, 2017.
Article in English | MEDLINE | ID: mdl-28769790

ABSTRACT

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.

15.
J Nutr Biochem ; 44: 11-21, 2017 06.
Article in English | MEDLINE | ID: mdl-28343084

ABSTRACT

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.


Subject(s)
Insulin-Secreting Cells/drug effects , NF-E2-Related Factor 2/metabolism , Signal Transduction , Stilbenes/pharmacology , Animals , Antioxidants/pharmacology , Apoptosis/drug effects , Blood Glucose/metabolism , Caspase 3/genetics , Caspase 3/metabolism , Cell Line , Cell Survival/drug effects , Cytokines/blood , Diabetes Mellitus, Experimental/drug therapy , Insulin/blood , Insulin/metabolism , Insulin Secretion , Insulin-Secreting Cells/metabolism , Kelch-Like ECH-Associated Protein 1/genetics , Kelch-Like ECH-Associated Protein 1/metabolism , Male , Mice , NF-E2-Related Factor 2/genetics , Oxidative Stress/drug effects , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolism
17.
Sci Rep ; 6: 34053, 2016 10 11.
Article in English | MEDLINE | ID: mdl-27725731

ABSTRACT

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.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Drug Carriers , Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Triple Negative Breast Neoplasms/drug therapy , Acrylic Resins/chemistry , Acrylic Resins/pharmacology , Antineoplastic Combined Chemotherapy Protocols/chemistry , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Chitosan/chemistry , Chitosan/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacology , Female , Humans , MCF-7 Cells , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Oligopeptides/chemistry , Oligopeptides/pharmacology , Quercetin/chemistry , Quercetin/pharmacology , Silicon Dioxide/chemistry , Silicon Dioxide/pharmacology , Topotecan/chemistry , Topotecan/pharmacology , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology
19.
Eur J Pharmacol ; 777: 9-16, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26921755

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Hypoglycemic Agents/pharmacology , Lipid Peroxidation/drug effects , NF-E2-Related Factor 2/metabolism , Signal Transduction/drug effects , Stilbenes/pharmacology , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/drug therapy , Gene Expression Regulation/drug effects , Hypoglycemic Agents/therapeutic use , Insulin/blood , Lipoproteins/blood , Lipoproteins/metabolism , Liver/drug effects , Liver/metabolism , Mice , Oxidative Stress/drug effects , Stilbenes/therapeutic use
20.
ACS Appl Mater Interfaces ; 8(3): 2262-79, 2016 Jan 27.
Article in English | MEDLINE | ID: mdl-26771508

ABSTRACT

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.


Subject(s)
Breast Neoplasms/drug therapy , Magnetic Phenomena , Molecular Targeted Therapy , Nanocomposites/chemistry , Polymers/chemistry , Receptor, ErbB-2/metabolism , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Breast Neoplasms/pathology , Cell Survival/drug effects , Female , HeLa Cells , Hemolysis/drug effects , Humans , Hydrogen-Ion Concentration , MCF-7 Cells , Mice, Inbred BALB C , Microscopy, Fluorescence , Tamoxifen/pharmacology , Tamoxifen/therapeutic use
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