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1.
ACS Appl Bio Mater ; 7(1): 154-167, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38088856

ABSTRACT

The drug delivery system for transporting anticancer agents to targeted tissues in the body is a challenging issue. In search of a suitable biocompatible carrier having controlled and sustained drug release properties of poorly soluble drugs, carbon nano-onions (CNOs) were loaded with an anticancer drug, bis-chloroethyl nitrosourea (BCNU/carmustine). CNOs being autofluorescent, drug-loaded functionalized CNOs (f-CNO-BCNU) can be detected in vivo. Transmission electron microscopy (TEM) and differential light scattering (DLS) techniques were used to analyze the sizes of these f-CNOs. The molecular study revealed that the f-CNO-BCNU readily and noncovalently binds with the folate receptors present on the cancer cell surface in excess. Computer modeling and molecular dynamics simulation followed by binding free energy calculation shows f-CNOs have -29.9 kcal/mol binding free energy, and it noncovalently binds the receptor FRα using loop dynamics of three essential loops present in the protein along with polar stabilization interactions provided by Asp55 and Glu86 residues present in the active site. The f-CNO effectively decreased cancer cell viability with a low IC50 value (the concentration that led to 50% killing of the cells). The cell-based Franz diffusion assay was performed to study the drug release profile. The f-CNO-BCNUs also decreased the mitochondrial membrane potential of U87 cells, increased reactive oxygen species release, and caused a loss of mitochondrial membrane integrity. The f-CNOs also increased the percentage of apoptotic cells observed by the Annexin V assay. Based on observed results, it can be concluded that the f-CNO-BCNU efficiently targets the cancer cells, enhances the bioavailability of carmustine, and can be used as a smart chemotherapeutic agent. This strategy offers better patient compliance and greater bioavailability of the drug.


Subject(s)
Antineoplastic Agents , Glioblastoma , Humans , Carmustine/pharmacology , Carmustine/chemistry , Glioblastoma/drug therapy , Carbon/chemistry , Pharmaceutical Preparations , Onions , Drug Delivery Systems , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use
2.
ACS Biomater Sci Eng ; 9(10): 5886-5899, 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37747783

ABSTRACT

Ultrasensitive detection of serotonin is crucial for the early diagnosis of several diseases like Parkinson's and Alzheimer's. Most of the existing detection strategies are still not suitable for sensitive point-of-care applications. This study presents direct molecular imprinting of serotonin on the surface of three-dimensional zinc oxide (ZnO) nanorod devices connected in a field effect transistor (FET) configuration to achieve ultrasensitive, real-time, and rapid detection with a convenient and affordable approach, which has significant potential for translation to clinical settings. This strategy has enabled pushing the detection limit to 0.1 fM in a physiological analyte in real time with screen-printed electrodes, thereby resulting in the convenient batch fabrication of sensors for clinical validation. The response of the sensor with the clinical sample has been correlated with that of the gold standard and has been observed to be statistically similar.

3.
Mol Neurobiol ; 60(4): 2036-2050, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36598649

ABSTRACT

Misfolded peptide amyloid beta (Aß42), neurofibrillary tangles of hyper-phosphorylated tau, oxidative damage to the brain, and neuroinflammation are distinguished determinants of Alzheimer's disease (AD) responsible for disease progression. This multifaceted neurodegenerative disease is challenging to cure under a single treatment regime until the key disease determinants are traced for their sequential occurrence in disease progression. In an early report, a novel side-chain tripeptide containing PEGylated block copolymer has been tested thoroughly in vitro and in silico for the early inhibition of Aß42 aggregation as well as degradation of preformed Aß42 fibril deposits. The present study demonstrates a preclinical assessment of the PEGylated block copolymer in colchicine-induced AD-mimicking rodent model. The colchicine-induced Wistar rats receiving an intranasal delivery of the block copolymer at a daily dosage of 100 µg/kg and 200 µg/kg body weights, respectively, for 14 days manifested a notable attenuation of behavioral deficit pattern, oxidative stress, and neurotransmitters' deficiency as compared to the untreated ones. The current study also reports the ameliorative property of the PEGylated compound for progressive neuroinflammation and decreased mitochondrial bioenergetics in astrocytoma cell line, viz., U87. A closer look into the drug mechanism of action of a compact 3D PEGylated block copolymer confirmed its disintegrative interaction with Aß42 fibril via in silico simulation. The results obtained from this study signify the potential of the novel PEGylated block copolymer to ameliorate the cognitive decline and progressive oxidative insults in AD and may envision a successful clinical phase trial. The amelioration of disease condition of colchicine-induced AD rat. Initially the rat has given colchicine via stereotaxic surgery which led to a mimicking condition of AD including neuronal death in hippocampal CA1 region. After recovery from the surgery, the rat was treated with the PEGylated block copolymer through intranasal delivery, and this has led to the decrease in neuronal death in hippocampal CA1 region. The mechanism of drug action has shown by the separation of monomer chains of Aß42.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Rats , Animals , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Rodentia/metabolism , Neuroinflammatory Diseases , Rats, Wistar , Cognition , Oxidative Stress , Polyethylene Glycols , Disease Progression , Peptide Fragments/metabolism , tau Proteins/metabolism
4.
Breast Cancer ; 29(4): 748-760, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35511410

ABSTRACT

BACKGROUND: Recent evidence confirmed that the maximum energy in metastatic breast cancer progression is supplied by fatty acid oxidation (FAO) governed by a rate-limiting enzyme, carnitine palmitoyltransferase 1 (CPT1). Therefore, the active limitation of FAO could be an emerging aspect to inhibit breast cancer progression. Herein, for the first time, we have introduced quercetin (QT) from a non-dietary source (Mikania micrantha Kunth) to limit the FAO in triple-negative breast cancer cells (TNBC) through an active targeting of CPT1. METHODS: Molecular quantification of QT was confirmed through high-performance thin-layer chromatography (HPTLC). Computational docking analyses predicted the binding affinity of QT to CPT1. Cell-based seahorse energy efflux investigated the mitochondrial respiration rate, glycolytic function and ATP production rate. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) investigated the FAO-associated gene expression. Matrigel cell invasion and fluorescence-activated cell sorting analyses investigated anti-metastatic and apoptotic cell death induction activities, respectively. In vivo antitumor activities were checked using the female breast cancer mice (BALB/c) model. RESULTS: QT resulted in a significant reduction in the intracellular mitochondrial respiration and glycolytic function, limiting extensive ATP production. In turn, QT elevated the reactive oxygen species (ROS) and depleted antioxidant levels to induce anti-metastatic and cell apoptosis activities. qRT-PCR resulted in active healing of altered FAO-associated gene expression which was well predicted through the successful in silico molecular binding potentiality of QT to CPT1. Subsequently, QT has shown excellent in vivo antitumor activities through the altered lipid profile and oxidative stress-healing capabilities. CONCLUSIONS: All the obtained data significantly grounded the fact that QT could be a promising metabolism-targeted breast cancer therapeutic.


Subject(s)
Carnitine O-Palmitoyltransferase , Triple Negative Breast Neoplasms , Adenosine Triphosphate/metabolism , Animals , Carnitine O-Palmitoyltransferase/genetics , Carnitine O-Palmitoyltransferase/metabolism , Fatty Acids/genetics , Fatty Acids/metabolism , Female , Humans , Mice , Oxidation-Reduction , Quercetin/pharmacology , Quercetin/therapeutic use , Triple Negative Breast Neoplasms/pathology
5.
J Herb Med ; 32: 100554, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35251909

ABSTRACT

INTRODUCTION: The need for specific therapeutics against infectious diseases is made very important at this moment by the COVID-19 pandemic caused by SARS-COV-2. Vaccines containing live attenuated or heat-inactivated pathogens elicit robust immune responses, but their safety is sometimes not assured. Subunit vaccines consisting of the most potent antigenic protein or carbohydrates of the pathogen are safer but often induce a weak immune response. Traditional Ayurveda medicines have a long history of safety and may act as immuno-modulators or vaccine adjuvants. They can reduce the amount of vaccine booster doses required to elicit an immune response against any pathogen. The main objective of this review is a mechanistic evaluation of the antiviral potential of Ayurveda herbal compositions for their ability to increase cytokine expression and enhance NK cell activity, activate CD4/ CD8 + T cells, and increase the formation of IL-2 and IFNγ against SARS-CoV-2 infection. METHODS: Various peer-reviewed publications, books, monographs, and reputed search engines were reviewed in depth. Information available from the Ayurvedic Pharmacopoeia and in recent in silico analyses were compared in order to understand the mechanism of action of herbal components against SARS-CoV-2. RESULTS: It was found in various molecular docking and molecular dynamics studies that many bioactive natural components of Ayurvedic medicines could prevent viral entry or multiplication within a human host. CONCLUSION: Ayurvedic herbal medicines can be used either independently as therapeutics or as a complement to the modern-day recombinant vaccines with immediate effect. Ayurveda-based adjuvant therapy can also efficiently manage the secondary symptoms of COVID 19 patients.

6.
Int Nano Lett ; 11(3): 197-203, 2021.
Article in English | MEDLINE | ID: mdl-33425283

ABSTRACT

PURPOSE OF REVIEW: The pandemic COVID-19 has affected more than seventy million people globally. The whole world is eagerly waiting for an effective antiviral therapy to combat COVID-19, but it is yet to get. The emergence of COVID-19 makes imperative the need for safe and potent antiviral drugs. Many metal nanoparticles exhibit significant antiviral potential against many viral diseases. The Ayurvedic system of medicine is the treasure of many metal nanoparticulate drugs termed as Bhasma. RECENT FINDINGS: Gold, silver, copper, zinc and iron oxide nanoparticles are effective against coronavirus. A possible mechanism of action of the metal nanoparticles against coronavirus is a disruption of outer layers of coronavirus. Swarna Bhasma, Rajata Bhasma, Tamra Bhasma and Yashada Bhasma are recommended for COVID-19 treatment due to the ability to reduce the plasma interleukins, interferons and TNFα levels. SUMMARY: The Ayurvedic Bhasma preparations are unique metal nanoparticles. These metal nanoparticles are safe, stable in solid state and are having excellent biological activities. Ayurvedic metal nanoparticles, Swarna Bhasma, Rajata Bhasma, Tamra Bhasma and Yashada Bhasma could be proved as novel antiviral agents against SARS-CoV-2 for their anti-inflammatory, immunomodulatory, antiviral and adjuvant activities.

7.
Biophys Chem ; 270: 106538, 2021 03.
Article in English | MEDLINE | ID: mdl-33418105

ABSTRACT

The current global outbreak of COVID-19 due to SARS-CoV-2 is an unprecedented humanitarian crisis. Considering the gravity of its impact there is an immediate need to develop a detection technique that is sensitive, specific, fast, and affordable for the clinical diagnosis of the disease. Real time Polymerase Chain Reaction (RT-PCR)-based detection platforms are contemplated to be the gold standard to detect viral RNA. However, that may be susceptible to errors, and there is a risk of obtaining false results, which ultimately compromises the strategy of efficient disease management. Several modern techniques exhibiting assured results with enhanced sensitivity and specificity against the SARS-CoV-2 associated viral components or immune response against it have been developed and may be implemented. The review deals with the conventional RT-PCR detection techniques and compares them to other detection platforms viz., biosensor based detection of antigens, fluorescent or colorimetric detection systems including CRISPR-Cas 13 based SHERLOCK kit, CRISPR Cas-9 based FELUDA test kit, CRISPR DETECTR kit, Next Generation Sequencing or microarray-based kits. These modern techniques are great as a point of care detection methods but should be followed by RT PCR based detection for the confirmation of COVID-19 status.


Subject(s)
Biosensing Techniques/methods , COVID-19/diagnosis , SARS-CoV-2/genetics , Antigens, Viral/analysis , COVID-19/virology , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , High-Throughput Nucleotide Sequencing , Humans , Immunoassay , Nucleic Acid Amplification Techniques , RNA, Viral/analysis , SARS-CoV-2/isolation & purification
8.
Mol Biol Rep ; 47(5): 3745-3763, 2020 May.
Article in English | MEDLINE | ID: mdl-32361897

ABSTRACT

Cancer cells need extensive energy supply for their uncontrolled cell division and metastasis which is exclusively dependent on neighboring cells, especially adipocytes. Herein, we have introduced a novel herbometallic nano-drug, Heerak Bhasma nanoparticle (HBNP) from natural resources showing high potential in the reduction of energy supply thereby promoting cell death in breast cancer cells. Inductively coupled plasma optical emission spectra (ICP-OES), atomic absorption spectra (AAS), Raman spectra, X-ray diffraction analyses confirmed the physicochemical properties of HBNP. The differential light scattering (DLS) and field emission scanning electron microscope (FESEM) analyzed the cell-permeable size of HBNP, whereas, cell viability assay confirmed the non-toxic effect. Seahorse energy efflux assay, apoptotic cell quantification, ROS, mitochondrial membrane potential, in vivo oxidative stress etc. were measured using standard protocol. The notable changes in cancer energy metabolism investigated by cellular Mito and Glyco-stress analyses confirmed the HBNP induced intracellular energy depletion. Also, a significant reduction in mitochondrial membrane potential and subsequently, extensive reactive oxygen species (ROS) generations were observed in presence of HBNP followed by the induction of cell apoptosis. The cell invasion and wound healing assay followed by reduced expression both protein (MMP 2, MMP 9) and cytokine (IL6, IL10) had signified the effectiveness of HBNP against cancer metastasis. In addition, HBNP also showed an excellent antitumor activity in vivo followed by developing healing characteristics due to oxidative stress. All these findings strongly suggest that HBNP has the potential to be the new cancer therapeutic. A schematic phenomenon represents the overall HBNP mediated anticancer activity via limitation of both fatty acid uptake and energy metabolism.


Subject(s)
Breast Neoplasms/drug therapy , Medicine, Ayurvedic/methods , Metal Nanoparticles/therapeutic use , Animals , Apoptosis/drug effects , Breast Neoplasms/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Energy Metabolism/physiology , Female , Humans , Membrane Potential, Mitochondrial/drug effects , Mice , Mice, Inbred BALB C , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism
9.
Nanomedicine (Lond) ; 14(9): 1173-1189, 2019 05.
Article in English | MEDLINE | ID: mdl-31050596

ABSTRACT

Aim: Preparation of a herbometallic nano-drug, Rasa Manikya nanoparticle (RMNP) and investigation of its antimicrobial, and anticancer activity. Materials & methods: Physicochemical characterizations of RMNP were performed using different analytical methods. The antimicrobial and anticancer potential of RMNPs were assessed by an in vitro cellular assay. Bacterial cell wall lysis was observed by field emission scanning electron microscopy and mitochondrial metabolism alteration factor was measured via standard method. Results: Physicochemical analysis confirmed that RMNP was rich in mineral constituents. Synergistic effect of RMNPs enhanced lysis of bacterial peptidoglycan layers and impaired cellular redox balance, GSH/NADPH level followed by induction of cell apoptosis. Conclusion: The present study confirms that RMNP can be used as a dual therapeutic option for combating drug-resistant microbial strains and breast cancer.


Subject(s)
Anti-Bacterial Agents/chemistry , Antineoplastic Agents/chemistry , Arsenicals/chemistry , Metal Nanoparticles/chemistry , Oxidative Stress , Plant Preparations/chemistry , Sulfides/chemistry , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Arsenicals/pharmacology , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Enterobacter/drug effects , Escherichia coli/drug effects , Humans , Medicine, Ayurvedic , Microbial Sensitivity Tests , Oxidation-Reduction , Plant Preparations/pharmacology , Staphylococcus aureus/drug effects , Sulfides/pharmacology
10.
Mol Neurobiol ; 56(9): 6551-6565, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30868446

ABSTRACT

The amyloid cascade hypothesis dealing with the senile plaques is until date thought to be one of the causative pathways leading to the pathophysiology of Alzheimer's disease (AD). Though many aggregation inhibitors of misfolded amyloid beta (Aß42) peptide have failed in clinical trials, there are some positive aspects of the designed therapeutic peptides for diseases involving proteinaceous aggregation. Here, we evaluated a smart design of side chain tripeptide (Leu-Val-Phe)-based polymeric inhibitor addressing the fundamental hydrophobic amino acid stretch "Lys-Leu-Val-Phe-Phe-Ala" (KLVFFA) of the Aß42 peptide. The in vitro analyses performed through the thioflavin T (ThT) fluorescence assay, infrared spectroscopy, isothermal calorimetry, cytotoxicity experiments, and so on evinced a promising path towards the development of new age AD therapeutics targeting the inhibition of misfolded Aß42 peptide fibrillization. The in silico simulations done contoured the mechanism of drug action of the present block copolymer as the competitive inhibition of aggregate-prone hydrophobic stretch of Aß42. Graphical abstract The production of misfolded Aß42 peptide from amyloid precursor protein initiates amyloidosis pathway which ends with the deposition of fibrils via the oligomerization and aggregation of Aß42 monomers. The side chain tripeptide-based PEGylated polymer targets these Aß42 monomers and oligomers inhibiting their aggregation. This block copolymer also binds and helps degrading the preformed fibrils of Aß42.


Subject(s)
Alzheimer Disease/drug therapy , Polyethylene Glycols/chemistry , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/ultrastructure , Cell Death , Cell Line, Tumor , Cell Survival , Humans , Ligands , Molecular Dynamics Simulation , Polyethylene Glycols/chemical synthesis , Static Electricity
11.
Dalton Trans ; 47(44): 15907-15916, 2018 Nov 13.
Article in English | MEDLINE | ID: mdl-30374503

ABSTRACT

Developing chemosensors for efficient detection of Al3+ and picric acid in water is in high demand but challenging. In this paper, we have demonstrated the potential of a probe, 6,6'-(1E,1'E)-(2-hydroxypropane-1,3-diyl)bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)bis(2-methoxyphenol) (H2Vm), as a "switch-on" Al3+ responsive fluorescence chemosensor in water. In addition to the ability of H2Vm to sense Al3+, the Al2-Vm2 complex offers selectivity towards picric acid (PA) in HEPES buffer (pH = 7.4) solution (detection limit (20.13 × 10-9 M) via "switch-off" mode. The reversible fluorescence response with low detection limit (11.34 × 10-9 M) in the pH range of 6.0-9.0 makes H2Vm suitable for tracking Al3+ in live HCT cells. The resulting Al2-Vm2 complex is also responsive towards PA in HCT cells. Thus, a versatile fluorescence spectroscopy-based chemosensor for Al3+ and picric acid has been developed with possible applications in human health and national security.

12.
Int J Neurosci ; 128(5): 449-463, 2018 May.
Article in English | MEDLINE | ID: mdl-29076790

ABSTRACT

Misfolded ß-sheet structures of proteins leading to neurodegenerative diseases like Alzheimer's disease (AD) and Parkinson's disease (PD) are in the spotlight since long. However, not much was known about the functional amyloids till the last decade. Researchers have become increasingly more concerned with the degree of involvement of these functional amyloids in human physiology. Interestingly, it has been found that the human body is exposed to a tremendous systemic amyloid burden, especially, during aging. Although many findings regarding these functional amyloids come up every day, some questions still remain unanswered like do these functional amyloids directly involve in the fibrillization of amyloid beta (Aß) 42 peptide or enhance the Aß42 aggregation rate; whether functional bacterial amyloids (FuBA) co-localize with the senile plaques of AD or not. A detailed review of the latest status regarding the interrelationship between functional amyloids, pathogenic amyloids and misfolded prions and therapeutic assessment of functional amyloids for the treatment of neurodegenerative diseases can help identify an alternative medication for neurodegeneration. A unique mathematical model is proposed here for alteration of Aß42 aggregation kinetics in AD to carve out the future direction of therapeutic consideration.


Subject(s)
Amyloid beta-Peptides/metabolism , Amyloid/metabolism , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/therapy , Amyloid/chemistry , Biological Evolution , Computer Simulation , Humans , Models, Biological , Neurodegenerative Diseases/etiology , Prion Proteins/metabolism , Proteostasis Deficiencies/complications
13.
Dalton Trans ; 46(29): 9498-9510, 2017 Jul 25.
Article in English | MEDLINE | ID: mdl-28702605

ABSTRACT

A reaction of N1,N3-bis(3-methoxysalicylidene) diethylenetriamine (H2Vd) and Zn(NO3)2·6H2O, ZnBr2, ZnI2 and Cd(NO3)2·4H2O in a methanol solution led to zinc and cadmium complexes of different nuclearities, [Zn2(Vd·H)2(X)2]·CH3OH (X = NO3, Br, I) [1a, 1b and 1c] and Cd3(Vd)2(NO3)2 (2). In 1(a-c), two H2Vd ligands bridge the two metal centers whereas in 2, they provide sideways support to two terminal Cd2+ ions, providing an all-oxygen envelope to the central Cd2+ ion. All four compounds were characterized by elemental analysis, FT-IR spectroscopy and single crystal X-ray diffraction analysis. Complexes 1(a-c) exhibit dinuclear structures, whereas 2 exhibits a nearly linear trinuclear structure. The structural differences among these complexes are attributable to various coordination modes and flexible configurations of the H2Vd ligand. The ligand H2Vd is an excellent probe for sensing Zn2+ in solution, whereas complexes 1(a-c) are able to selectively detect pyrophosphate (PPi) in aqueous medium. The structure of the pyrophosphate (PPi) complex has been proposed using DFT calculations and the selectivity is due to the unique ability of this anion to simultaneously coordinate to both the Zn metal centers. The anticancer activity of complexes 1(a-c) was also explored.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Diphosphates/chemistry , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Water/chemistry , Zinc/chemistry , HCT116 Cells , Humans , Models, Molecular , Molecular Conformation , Schiff Bases/chemistry
15.
Dalton Trans ; 44(12): 5763-70, 2015 Mar 28.
Article in English | MEDLINE | ID: mdl-25714669

ABSTRACT

A new quinoline based sensor was developed and applied for the selective detection of Cd(2+) both in vitro and in vivo. The designed probe displays a straightforward approach for the selective detection of Cd(2+) with a prominent fluorescence enhancement along with a large red shift (∼38 nm), which may be because of the CHEF (chelation-enhanced fluorescence) and ICT (internal charge transfer) processes after interaction with Cd(2+). The interference from other biologically important competing metal ions, particularly Zn(2+), has not been observed. The visible-light excitability of the probe merits in the viewpoint of its biological application. The probe enables the detection of intracellular Cd(2+) with non-cytotoxic effects, which was demonstrated with the live RAW cells. The experimentally observed change in the structure and electronic properties of the sensor after the addition of Cd(2+) were modelled by the density functional theory (DFT) and time-dependent density functional theory (TDDFT) computational calculations, respectively. Moreover, the test strip experiment with this sensor exhibits both absorption and fluorescence color changes when exposed to Cd(2+) in a mixed aqueous solution, which also makes the probe more useful. The minimum limit of detection of Cd(2+) by the probe was in the range of 9.9 × 10(-8) M level.


Subject(s)
Cadmium/analysis , Fluorescent Dyes/chemistry , Optical Imaging , Quinolines/chemistry , Cations, Divalent/analysis , Fluorescence , HCT116 Cells , Humans , Light , Spectrometry, Fluorescence , Water/analysis
16.
Analyst ; 139(1): 309-17, 2014 Jan 07.
Article in English | MEDLINE | ID: mdl-24255921

ABSTRACT

A new BODIPY-azaindole based fluorescent sensor 1 was designed and synthesized as a new colorimetric and ratiometric fluorescent chemosensor for fluoride. The binding and sensing abilities of sensor 1 towards various anions were studied by absorption, emission and (1)H NMR titration spectroscopies. The spectral responses of 1 to fluoride in acetonitrile-water were studied: an approximately 69 nm red shift in absorption and ratiometric fluorescent response was observed. The striking light yellow to deep brown color change in ambient light and green to blue emission color change are thought to be due to the deprotonation of the indole moiety of the azaindole fluorophore. From the changes in the absorption, fluorescence, and (1)H NMR titration spectra, proton-transfer mechanisms were deduced. Density function theory and time-dependent density function theory calculations were conducted to rationalize the optical response of the sensor. Results were supported by confocal fluorescence imaging and MTT assay of live cells.


Subject(s)
Acetic Acid/analysis , Boron Compounds/chemistry , Cell Shape , Fluorides/analysis , Optical Imaging/methods , Animals , Anions , HCT116 Cells , Humans , Mice
17.
PLoS Pathog ; 9(9): e1003611, 2013.
Article in English | MEDLINE | ID: mdl-24086132

ABSTRACT

Major gaps in our knowledge of pathogen genes and how these gene products interact with host gene products to cause disease represent a major obstacle to progress in vaccine and antiviral drug development for the herpesviruses. To begin to bridge these gaps, we conducted a dual analysis of Murine Cytomegalovirus (MCMV) and host cell transcriptomes during lytic infection. We analyzed the MCMV transcriptome during lytic infection using both classical cDNA cloning and sequencing of viral transcripts and next generation sequencing of transcripts (RNA-Seq). We also investigated the host transcriptome using RNA-Seq combined with differential gene expression analysis, biological pathway analysis, and gene ontology analysis. We identify numerous novel spliced and unspliced transcripts of MCMV. Unexpectedly, the most abundantly transcribed viral genes are of unknown function. We found that the most abundant viral transcript, recently identified as a noncoding RNA regulating cellular microRNAs, also codes for a novel protein. To our knowledge, this is the first viral transcript that functions both as a noncoding RNA and an mRNA. We also report that lytic infection elicits a profound cellular response in fibroblasts. Highly upregulated and induced host genes included those involved in inflammation and immunity, but also many unexpected transcription factors and host genes related to development and differentiation. Many top downregulated and repressed genes are associated with functions whose roles in infection are obscure, including host long intergenic noncoding RNAs, antisense RNAs or small nucleolar RNAs. Correspondingly, many differentially expressed genes cluster in biological pathways that may shed new light on cytomegalovirus pathogenesis. Together, these findings provide new insights into the molecular warfare at the virus-host interface and suggest new areas of research to advance the understanding and treatment of cytomegalovirus-associated diseases.


Subject(s)
Herpesviridae Infections/metabolism , Host-Pathogen Interactions/physiology , MicroRNAs/biosynthesis , Muromegalovirus/physiology , Transcription Factors/biosynthesis , Transcriptome , Up-Regulation , Animals , Cell Line, Transformed , Fibroblasts/metabolism , Fibroblasts/pathology , Fibroblasts/virology , Herpesviridae Infections/genetics , Herpesviridae Infections/pathology , Mice , MicroRNAs/genetics , Transcription Factors/genetics
18.
Inorg Chem ; 52(19): 10825-34, 2013 Oct 07.
Article in English | MEDLINE | ID: mdl-24067170

ABSTRACT

A structurally characterized new oxo-chromene functionalized rhodamine derivative L1 exhibits high selectivity toward Sn(4+) by forming a 1:1 complex, among other biologically important metal ions, as studied by fluorescence, absorption, and HRMS spectroscopy. Complexing with Sn(4+) triggers the formation of a highly fluorescent ring-open form which is pink in color. The sensor shows extremely high fluorescence enhancement upon complexation with Sn(4+), and it can be used as a "naked-eye" sensor. DFT computational studies carried out in mimicking the formation of a 1:1 complex between L1 and Sn(4+) resulted in a nearly planar pentacoordinate Sn(IV) complex. Studies reveal that the in situ prepared L1-Sn complex is selectively and fully reversible in presence of sulfide anions. Further, confocal microscopic studies confirmed that the receptor shows in vitro detection of Sn(4+) ions in RAW cells.


Subject(s)
Coordination Complexes/chemistry , Fluorescent Dyes/chemistry , Quantum Theory , Rhodamines/chemistry , Tin/chemistry , Cell Line, Tumor , Humans , Image Cytometry , Limit of Detection , Microscopy, Confocal , Molecular Structure , Rhodamines/classification , Tin/analysis
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