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1.
J Phys Chem Lett ; 15(11): 3078-3088, 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38467015

ABSTRACT

A biomimetic cell-based carrier system based on monocyte membranes and liposomes has been designed to create a hybrid "Monocyte-LP" which inherits the surface antigens of the monocytes along with the drug encapsulation property of the liposome. Förster resonance energy transfer (FRET) and polarization gated anisotropy measurements show the stiffness of the vesicles obtained from monocyte membranes (Mons), phosphatidylcholine membranes (LP), and Monocyte-LP to follow an increasing order of Mons > Monocyte-LP > LP. The dynamics of interface bound water molecules plays a key role in the elasticity of the vesicles, which in turn imparts higher delivery efficacy to the hybrid Monocyte-LP for a model anticancer drug doxorubicin than the other two vesicles, indicating a critical balance between flexibility and rigidity for an efficient cellular uptake. The present work provides insight on the influence of elasticity of delivery vehicles for enhanced drug delivery.


Subject(s)
Antineoplastic Agents , Liposomes , Liposomes/metabolism , Monocytes/metabolism , Doxorubicin , Drug Delivery Systems
2.
ChemMedChem ; : e202400037, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38459687

ABSTRACT

Non-invasive delivery of drugs is important for the reversal of respiratory diseases essentially by-passing metabolic pathways and targeting large surface area of drug absorption. Here, we study the inhalation of a redox nano medicine namely citrate functionalized Mn3O4 (C-Mn3O4) duly encapsulated in droplet evaporated aerosols for the balancing of oxidative stress generated by the exposure of Chromium (VI) ion, a potential lung carcinogenic agent. Our optical spectroscopic in-vitro experiments demonstrates the efficacy of redox balancing of the encapsulated nanoparticles (NP) for the maintenance of a homeostatic condition. The formation of Cr-NP complex as an excretion of the heavy metal is also demonstrated through optical spectroscopic and high resolution transmission optical microscopy (HRTEM). Our studies confirm the oxidative stress mitigation activity of the Cr-NP complex. A detailed immunological assay followed by histopathological studies and assessment of mitochondrial parameters in pre-clinical mice model with chromium (Cr) induced lung inflammation establishes the mechanism of drug action to be redox-buffering. Thus, localised delivery of C-Mn3O4 NPs in the respiratory tract via aerosols can act as an effective nanotherapeutic agent against oxidative stress induced lung inflammation.

3.
Int J Biol Macromol ; 253(Pt 6): 127317, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37820911

ABSTRACT

Purified calcium serine metalloprotease from Stenotrophomonas maltophilia strain SMPB12 exhibits highest enzyme activity at pH 9 and temperature range between 15 °C-25 °C. Enzyme supplemented with 40 µM Ca-Hap-NP (NP-protease) showed maximum elevated activity of 17.29 µmole/min/ml (1.9-fold of original protease activity). The thermostability of the enzyme was maintained for 1 h at 60 °C over an alkaline pH range 7.5-10, as compared to the NP untreated enzyme whose activity was of 8.97 µmole/min/ml. A significant loss of activity with EDTA (1.05 µmole/min/ml, 11.75 %), PMSF (0.93 µmole/min/ml, 10.46 %) and Hg2+ (3.81 µmole/min/ml, 42.49 %) was also observed. Kinetics study of NP-protease showed maximum decreases in Km (28.11 %) from 0.28 mM (NP untreated enzyme) to 0.22 mM (NP-protease) along with maximum increase in Vmax (42.88 %) from 1.25 µmole/min/ml to 1.79 µmole/min/ml at varying temperatures. The enhanced activity of NP-protease was able to efficiently degrade recalcitrant solid wastes like feather to produce value-added products like amino acids and helps in declogging recalcitrant solid wastes. The nano-enabled protease may be utilized in a smaller amount for degrading in bulk recalcitrant solid proteinaceous waste at 15 °C temperature as declogging agents providing an eco-friendly efficient process.


Subject(s)
Durapatite , Feathers , Animals , Feathers/metabolism , Durapatite/metabolism , Solid Waste , Peptide Hydrolases/metabolism , Bacteria/metabolism , Temperature , Forests , Hydrogen-Ion Concentration , Enzyme Stability
4.
Bioconjug Chem ; 34(8): 1407-1417, 2023 08 16.
Article in English | MEDLINE | ID: mdl-37289994

ABSTRACT

Here, our designed water-soluble NIR fluorescent unsymmetrical Cy-5-Mal/TPP+ consists of a lipophilic cationic TPP+ subunit that can selectively target and accumulate in a live-cell inner mitochondrial matrix where a maleimide residue of the probe undergoes faster chemoselective and site-specific covalent attachment with the exposed Cys residue of mitochondrion-specific proteins. On the basis of this dual localization effect, Cy-5-Mal/TPP+ molecules remain for a longer time period even after membrane depolarization, enabling long-term live-cell mitochondrial imaging. Due to the adequate concentration of Cy-5-Mal/TPP+ reached in live-cell mitochondria, it facilitates site-selective NIR fluorescent covalent labeling with Cys-exposed proteins, which are identified by the in-gel fluorescence assay and LC-MS/MS-based proteomics and supported by a computational method. This dual targeting approach with admirable photostability, narrow NIR absorption/emission bands, bright emission, long fluorescence lifetime, and insignificant cytotoxicity has been shown to improve real-time live-cell mitochondrial tracking including dynamics and interorganelle crosstalk with multicolor imaging applications.


Subject(s)
Fluorescent Dyes , Tandem Mass Spectrometry , Chromatography, Liquid , Fluorescent Dyes/chemistry , Mitochondria/metabolism , Cell Survival
5.
Mater Today Proc ; 80: 1846-1851, 2023.
Article in English | MEDLINE | ID: mdl-34178606

ABSTRACT

The current COVID-19 pandemic has increased the use of alcohol based hand sanitisers globally. These available alcohol based sanitisers cannot provide an antibacterial effect for an extended period of time, after the evaporation of ethanol. Hence, the need for a sanitiser with an anti-microbial activity combined with a long lasting effect is the need of the hour. In this study, we report the synthesis of a long lasting sanitiser from ozonated omega 9 fatty acid esters in an ethanolic medium. The formed vesicles made of the fatty acids have been characterized by DLS, Zeta potential, and time resolved fluorescence anisotropy studies. Ethanol although, provides an antibacterial effect, the effect is more pronounced in our prepared formulation owing to its high peroxide value that generates additional oxidative stress. Finally, this additional antimicrobial effect will have relevance in the current COVID-19 scenario in providing a long lasting hand sanitiser.

6.
Phys Chem Chem Phys ; 24(35): 20941-20952, 2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36053209

ABSTRACT

A new ratiometric fluorescent probe (E)-2-(benzo[d]thiazol-2-yl)-3-(8-methoxyquinolin-2-yl)acrylonitrile (HQCN) was synthesised by the perfect blending of quinoline and a 2-benzothiazoleacetonitrile unit. In a mixed aqueous solution, HQCN reacts with hydrazine (N2H4) to give a new product 2-(hydrazonomethyl)-8-methoxyquinoline along with the liberation of the 2-benzothiazoleacetonitrile moiety. In contrast, the reaction of hypochlorite ions (OCl-) with the probe gives 8-methoxyquinoline-2-carbaldehyde. In both cases, the chemodosimetric approaches of hydrazine and hypochlorite selectively occur at the olefinic carbon but give two different products with two different outputs, as observed from the fluorescence study exhibiting signals at 455 nm and 500 nm for hydrazine and hypochlorite, respectively. A UV-vis spectroscopy study also depicts a distinct change in the spectrum of HQCN in the presence of hydrazine and hypochlorite. The hydrazinolysis of HQCN exhibits a prominent chromogenic as well as ratiometric fluorescence change with a 165 nm left-shift in the fluorescence spectrum. Similarly, the probe in hand (HQCN) can selectively detect hypochlorite in a ratiometric manner with a shift of 120 nm, as observed from the fluorescence emission spectra. HQCN can detect hydrazine and OCl- as low as 2.25 × 10-8 M and 3.46 × 10-8 M, respectively, as evaluated from the fluorescence experiments again. The excited state behaviour of the probe HQCN and the chemodosimetric products with hydrazine and hypochlorite are studied by the nanosecond time-resolved fluorescence technique. Computational studies (DFT and TDDFT) with the probe and the hydrazine and hypochlorite products were also performed. The observations made in the fluorescence imaging studies with human blood cells manifest that HQCN can be employed to monitor hydrazine and OCl- in human peripheral blood mononuclear cells (PBMCs). It is indeed a rare case that the single probe HQCN is found to be successfully able to detect hydrazine and hypochlorite in PBMCs, with two different outputs.


Subject(s)
Hypochlorous Acid , Leukocytes, Mononuclear , Fluorescent Dyes/chemistry , Humans , Hydrazines , Hypochlorous Acid/chemistry , Spectrometry, Fluorescence
7.
Dalton Trans ; 51(28): 10779-10786, 2022 Jul 19.
Article in English | MEDLINE | ID: mdl-35611756

ABSTRACT

Detection of biological phosphate is very important for environmental and health care applications. In this study, a new ratiometric fluorescent probe (E)-N'-(3-(benzo[d]thiazol-2-yl)-2-hydroxybenzylidene) picolinohydrazide (BTP) is developed and exhibits a prominent excited-state intramolecular proton-transfer (ESIPT) mechanism. The probe BTP undergoes a unique phosphate induced hydrolytic reaction in mixed aqueous solution which produces a colorimetric change associated with a huge red-shift of ∼130 nm in the UV-visible absorption spectrum. Initially, BTP exhibits a strong fluorescence emission as the ESIPT process is 'on' and the tautomeric hydrogen remains flexible and is free to give two tautomeric forms. Eventually, after the addition of PO43-, the two tautomeric forms break and thereby shift the equilibrium towards the 'enol' form. The phosphate ion binds with BTP which is associated with a ratiometric change and accounts for an enhancement in the fluorescence intensity with a large blue shift and the limit of detection value of 8.33 × 10-8 M in a mixed aqueous medium. The binding constant (1.92 × 105 M-1) proportionally reflects the stability of the complexation between the binding sites of BTP with the guest PO43- anion. The probable mechanism is supported by the NMR spectroscopy studies. The sensing phenomenon is found to be reversible towards Zn2+ and thus the sensor beautifully mimics the INHIBIT logic gate. Observations have been made in fluorescence imaging studies with human peripheral blood mononuclear cells (PBMCs) which indicates that BTP can be employed to successfully monitor the phosphate ion in human PBMCs.


Subject(s)
Leukocytes, Mononuclear , Protons , Fluorescent Dyes/chemistry , Humans , Phosphates , Spectrometry, Fluorescence/methods , Water/chemistry
8.
Curr Drug Deliv ; 19(10): 991-1000, 2022.
Article in English | MEDLINE | ID: mdl-35346006

ABSTRACT

The direct delivery of therapeutic molecules is generally inefficient and has several problems. Hence, nanomedicines with targeted and controlled delivery applications have been an exciting field of research for the past decade. In this regard, the adjustable properties of inorganic nanoparticles like particle size distribution, ability to change the targeting ligand to have a higher affinity towards the pathologic cell, and controlled delivery properties have made them indispensable for targeted drug delivery applications. Changing the ligand on the surface of the inorganic nanoparticle can direct different therapeutic molecules to different organs like the liver, spleen, kidney, bone, and even brain. However, while the other targeted nanomedicines are well-reported, the targeting of therapeutics to bone marrow cells is sparse in the literature. Hence, the administration of therapeutics for bone-related disorders, like bone metastases, leads to several problems, such as severe systemic toxicity and suboptimal efficacy. In this direction, we have shown our successful effort to functionalise a model inorganic nanoparticle (Fe2O3) by glutamate ligand which is reported to have a high affinity towards the NMDA receptors of the bone cells. We have performed spectroscopic studies to characterize the nano-hybrid. We have shown that the cargo or the Fe2O3 nanoparticle possesses the ability to generate photo-induced reactive oxygen species (ROS), thereby leading to a therapeutic opportunity for bone metastases. In addition, the nanoparticle also possesses the ability to generate enhanced ROS on X-ray irradiation, which may provide a new strategy for bone metastases and cancer therapy. Also, this paper reviews the advancement in the drug delivery applications of inorganic nanoparticles and highlights the crosstalk between the inorganic nanoparticles with the conjugated targeting ligand for efficient delivery applications.


Subject(s)
Iron , Nanoparticles , Bone Marrow , Drug Delivery Systems/methods , Glutamic Acid , Ligands , Nanoparticles/chemistry , Pharmaceutical Preparations , Reactive Oxygen Species , X-Rays
9.
Chembiochem ; 23(9): e202200109, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35225409

ABSTRACT

Drug delivery to a target without adverse effects is one of the major criteria for clinical use. Herein, we have made an attempt to explore the delivery efficacy of SDS surfactant in a monomer and micellar stage during the delivery of the model drug, Toluidine Blue (TB) from the micellar cavity to DNA. Molecular recognition of pre-micellar SDS encapsulated TB with DNA occurs at a rate constant of k1 ∼652 s-1 . However, no significant release of encapsulated TB at micellar concentration was observed within the experimental time frame. This originated from the higher binding affinity of TB towards the nano-cavity of SDS at micellar concentration which does not allow the delivery of TB from the nano-cavity of SDS micelles to DNA. Thus, molecular recognition controls the extent of DNA recognition by TB which in turn modulates the rate of delivery of TB from SDS in a concentration-dependent manner.


Subject(s)
DNA , Micelles , Genomics , Spectrum Analysis , Surface-Active Agents
10.
Commun Biol ; 4(1): 1013, 2021 08 26.
Article in English | MEDLINE | ID: mdl-34446827

ABSTRACT

Targeting reactive oxygen species (ROS) while maintaining cellular redox signaling is crucial in the development of redox medicine as the origin of several prevailing diseases including chronic kidney disease (CKD) is linked to ROS imbalance and associated mitochondrial dysfunction. Here, we have shown that a potential nanomedicine comprising of Mn3O4 nanoparticles duly functionalized with biocompatible ligand citrate (C-Mn3O4 NPs) can maintain cellular redox balance in an animal model of oxidative injury. We developed a cisplatin-induced CKD model in C57BL/6j mice with severe mitochondrial dysfunction and oxidative distress leading to the pathogenesis. Four weeks of treatment with C-Mn3O4 NPs restored renal function, preserved normal kidney architecture, ameliorated overexpression of pro-inflammatory cytokines, and arrested glomerulosclerosis and interstitial fibrosis. A detailed study involving human embryonic kidney (HEK 293) cells and isolated mitochondria from experimental animals revealed that the molecular mechanism behind the pharmacological action of the nanomedicine involves protection of structural and functional integrity of mitochondria from oxidative damage, subsequent reduction in intracellular ROS, and maintenance of cellular redox homeostasis. To the best of our knowledge, such studies that efficiently treated a multifaceted disease like CKD using a biocompatible redox nanomedicine are sparse in the literature. Successful clinical translation of this nanomedicine may open a new avenue in redox-mediated therapeutics of several other diseases (e.g., diabetic nephropathy, neurodegeneration, and cardiovascular disease) where oxidative distress plays a central role in pathogenesis.


Subject(s)
Mitochondria/physiology , Nanomedicine , Reactive Oxygen Species/administration & dosage , Renal Insufficiency, Chronic/therapy , Animals , Female , Male , Mice , Oxidation-Reduction
11.
Nanomedicine (Lond) ; 16(10): 801-818, 2021 04.
Article in English | MEDLINE | ID: mdl-33900109

ABSTRACT

Aim: An antibiotic-conjugated protein-stabilized nanoparticle hybrid system was developed to combat the challenges faced during the treatment of drug-resistant bacterial biofilm-associated infections. Materials & methods: Biocompatible silver nanoparticles were synthesized using intracellular protein and gentamycin was attached. The resulting nanohybrid was characterized and its antibacterial efficiency was assessed against Gram-positive, Gram-negative and drug-resistant bacteria. Results: Spectroscopic and electron microscopic analysis revealed that the nanoparticles were spherical with a diameter of 2-6 nm. Red-shifting of the surface plasmon peak and an increase in hydrodynamic diameter confirmed attachment of gentamycin. The nanohybrid exhibited antibacterial efficiency against a range of bacteria with the ability to inhibit and disrupt bacterial biofilm. Conclusion: A unique nanohybrid was designed that has potential to be used to control drug-resistant bacterial infections in the future.


Subject(s)
Bacterial Infections , Metal Nanoparticles , Anti-Bacterial Agents/pharmacology , Biofilms , Gentamicins , Humans , Microbial Sensitivity Tests , Silver
12.
Bioconjug Chem ; 32(4): 833-841, 2021 04 21.
Article in English | MEDLINE | ID: mdl-33826302

ABSTRACT

Herein, we have designed and synthesized unsymmetrical visible Cy-3 and near-infrared (NIR) Cy-5 chromophores anchoring mitochondria targeting functional group conjugated with a Phe-Phe dipeptide by a microwave-assisted Fmoc solid phase peptide synthesis method on Wang resin. These dipeptide-based Cy-3-TPP/FF as well as Cy-5-TPP/FF molecules self-assemble to form fluorescent nanotubes in solution, and it has been confirmed by TEM, SEM, and AFM. The Cy-3-TPP/FF and Cy-5-TPP/FF molecules in solution exhibit narrow excitation as well as emission bands in the visible and NIR region, respectively. These lipophilic cationic fluorescent peptide molecules spontaneously and selectively accumulate inside the mitochondria of human carcinoma cells that have been experimentally validated by live cell confocal laser scanning microscopy and display a high Pearson's correlation coefficient in a colocalization assay. Live cell multicolor confocal imaging using the NIR Cy-5-TPP/FF in combination with other organelle specific dye is also accomplished. Moreover, these lipophilic dipeptide-based cationic molecules reach the critical aggregation concentration inside the mitochondria because of the extremely negative inner mitochondrial membrane potential [(ΔΨm)cancer ≈ -220 mV] and form supramolecular nanotubes which are accountable for malignant mitochondria targeted early apoptosis. The early apoptosis is arrested using Cy-5-TPP/FF and confirmed by annexin V-FITC/PI apoptosis detection assay.


Subject(s)
Apoptosis , Dipeptides/chemistry , Mitochondria/metabolism , Nanotubes/chemistry , Cell Survival , Fluorescence , Humans , Hydrogen-Ion Concentration , Microscopy/methods , Protein Structure, Secondary , Spectroscopy, Fourier Transform Infrared/methods , Spectroscopy, Near-Infrared/methods , Tumor Cells, Cultured
13.
Biochem Genet ; 59(3): 781-798, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33543406

ABSTRACT

Increasing burden of non-communicable diseases like diabetes and cardiovascular disorders has made the global health scenario more challenging. Dyslipidemia in diabetes is a compounding risk factor for cardiovascular diseases, but there is dearth of identifying appropriate signatures to address this issue. The protein, adiponectin, is actively involved in regulating glucose levels as well as fatty acid breakdown playing crucial role in dyslipidemia and vascular complications. To identify the underlying genetic and molecular profile of adiponectin metabolic pathway in diabetic dyslipidemia and to correlate it with known biochemical and oxidative stress parameters of T2DM, we performed a case-control study in a total 264 individuals belonging to three categories such as diabetes with dyslipidemia (n = 88), diabetes without dyslipidemia (n = 86) and normal healthy controls (n = 90). Expression of adiponectin (ADIPOQ) and its receptors (ADIPOR1 and ADIPOR2) were measured in visceral and subcutaneous adipose tissues. A significant downregulated expression of ADIPOQ and its receptors in adipose tissues and PBMCs were linked with diabetic dyslipidemic condition. A multiple linear regression followed by MDR analysis implicated the elevated plasma malondialdehyde and decreased adiponectin level to be correlated with diabetic dyslipidemia. More interestingly, two single nucleotide polymorphisms of ADIPOQ (rs2241766 and rs1501299) were genetically associated with the risk of developing dyslipidemia. Other important biochemical factors found to be increased in diabetic dyslipidemic conditions included plasma C-reactive protein and 4-hydroxynonenal adducts. Our results explore, a complex interplay of genetic and biochemical parameters in diabetic dyslipidemia which is significant from the perspective of risk stratification and novel therapeutic strategy development.


Subject(s)
Adiponectin/genetics , Diabetes Mellitus, Type 2/genetics , Dyslipidemias/metabolism , Lipid Peroxidation , Polymorphism, Single Nucleotide , Adult , Alleles , Case-Control Studies , Diabetes Mellitus, Type 2/complications , Dyslipidemias/complications , Dyslipidemias/genetics , Female , Genotype , Haplotypes , Humans , Male , Middle Aged
14.
Food Funct ; 12(3): 1063-1078, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33443517

ABSTRACT

According to population-based studies, lung cancer has become one of the leading causes of death globally in males and is also rising in females at an alarming rate. The aim of this study was to exploit the inherent properties of eugenol to restrict the growth of cancer cells in a tobacco-related human carcinogen NDEA-induced lung carcinogenesis model in vivo as a chemopreventive agent. More precisely, by utilizing its abundance in nature, eugenol (a component of clove) was utilized to establish the molecular mechanism of chemoprevention in the NDEA-induced mouse lung carcinogenesis model in a substantial cost-effective manner and was validated in the A549 human lung cancer cell line. Our study especially targeted the tiny, drug-resistant, and most virulent subpopulation of cancer cells called CSCs by targeting their regulator molecule ß-catenin. The non-toxic dosage of eugenol was shown to enhance apoptosis, simultaneously suppressing cell proliferation in the lung tissue of carcinogen-treated mice without affecting the normal mice. Combining cellular apoptosis and proliferation, eugenol showed an exceptional chemopreventive potential in this lung carcinogenesis model. Importantly, eugenol strongly restricted the lung carcinoma in the mild dysplastic stage as a chemopreventive agent. The molecular analysis remarkably depicted the restriction of ß-catenin nuclear transportation. The minimized total ß-catenin pool and induced N-terminal Ser37 phosphorylation form after eugenol treatment resulted in its cytoplasmic degradation. Consequently, CSC markers such as CD44, Oct4, EpCAM, and Notcht1, whose expression is dependent on ß-catenin decreased significantly, as proven by IHC, ICC, and WB analysis both in vivo and in vitro. The in vitro secondary sphere formation assay also proved the remarkably repressed CSC population, and hence the virulence. In another way, eugenol was proven to significantly enhance the degradation of ß-catenin when treated with the CK1α inhibitor D4476 in vitro by Western blot. CK1α in the Wnt/ß-catenin pathway plays a crucial role for tagging with the N-terminal Ser45 phosphorylation of ß-catenin, which ultimately opens a position for the decisive phosphorylation by GSK3ß at the Ser37 residue to take place. Thus, the conclusive extermination of CSCs achieved that was associated with recurrence due to treatment failure. That can help to achieve a longer and better quality of life in a natural, economical way.


Subject(s)
Eugenol/pharmacology , beta Catenin/metabolism , A549 Cells , Animals , Apoptosis , Diethylnitrosamine/toxicity , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Lung Neoplasms/chemically induced , Lung Neoplasms/drug therapy , Mice , Neoplasms, Experimental/chemically induced , Neoplasms, Experimental/drug therapy , beta Catenin/genetics
15.
Cytokine ; 145: 155300, 2021 09.
Article in English | MEDLINE | ID: mdl-32978033

ABSTRACT

The protozoan parasite L. donovani resides inside macrophages as amastigotes and inflicts a potentially lethal disease visceral leishmaniasis (VL). Due to absence of a vaccine, chemotherapy with antimonials, amphotericin B, miltefosine or paromomycin remains the only option for treating VL. Prolonged treatment with a single drug resulted in parasite strains resistant to each of these drugs. As immuno-suppression characterizes the disease, we examined whether eliciting immunosuppressive cytokines is a mechanism of manifestation of drug-resistance. We infected BALB/c mice with the clinical isolates of L. donovani- BHU1066 (sensitive), NS2 (antimony-resistant), BHU1064 (miltefosine-resistant), BHU919 (Amphotericin B-resistant) and BHU1020 (paromomycin-resistant)- from the respective drug-unresponsive patients and assessed splenic parasite load and production of pro-inflammatory and anti-inflammatory cytokines. Although the splenic parasite loads in the drug-resistant L. donovani-infected BALB/c mice were higher than that observed in the drug-sensitive parasites-infected mice, the cytokine profiles were not significantly different between these two sets of mice. The drug-resistance in L. donovani results from innate drug modulation but perhaps not from host immune-suppressive cytokines.


Subject(s)
Drug Resistance/immunology , Leishmania donovani/immunology , Leishmaniasis, Visceral/immunology , Amphotericin B/immunology , Animals , Antimony/immunology , Cytokines/immunology , Immunosuppression Therapy/methods , Leishmaniasis, Visceral/parasitology , Macrophages/immunology , Macrophages/parasitology , Mice , Mice, Inbred BALB C , Phosphorylcholine/analogs & derivatives , Phosphorylcholine/immunology , Protozoan Proteins/immunology
16.
Front Oncol ; 10: 529132, 2020.
Article in English | MEDLINE | ID: mdl-33194588

ABSTRACT

Molecular interaction of aromatic dyes with biological macromolecules are important for the development of minimally invasive disease diagnostic biotechnologies. In the present work, we have used Toluidine Blue (TB) as a model dye, which is a well-known staining agent for the diagnosis of oral cancer and have studied the interaction of various biological macromolecules (protein and DNA) with the dye at different pH. Our spectroscopic studies confirm that TB interacts with Human Serum Albumin (HSA), a model protein at very high pH conditions which is very hard to achieve physiologically. On the other hand, TB significantly interacts with the DNA at physiological pH value (7.4). Our molecular studies strengthen the understanding of the Toluidine Blue staining of cancer cells, where the relative ratio of the nucleic acids is higher than the normal intracellular content. We have also developed a non-invasive, non-contact spectroscopic technique to explore the possibility of quantitatively detecting oral cancer by exploiting the interaction of TB with DNA. We have also reported development of a prototype named "Oral-O-Scope" for the detection of Oral cancer and have carried out human studies using the prototype.

17.
Heliyon ; 6(9): e05053, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33015393

ABSTRACT

Non-enzymatic glycation of proteins is believed to be the root cause of high dietary sugar associated pathophysiological maladies. We investigated the structural changes in protein during progression of glycation using ribosylated Bovine Serum Albumin (BSA). Non enzymatic attachment of about 45 ribose molecules to BSA resulted in gradual reduction of hydrophobicity and aggregation as indicated by red-shifted tryptophan fluorescence, reduced ANS binding and lower anisotropy of FITC-conjugated protein. Parallely, there was a significant decrease of alpha helicity as revealed by Circular Dichroism (CD) and Fourier transformed-Infra Red (FT-IR) spectra. The glycated proteins assumed compact globular structures with enhanced Thioflavin-T binding resembling amyloids. The gross structural transition affected by ribosylation led to enhanced thermostability as indicated by melting temperature and Transmission Electron Microscopy. At a later stage of glycation, the glycated proteins developed non-specific aggregates with increase in size and loss of amyloidogenic behaviour. A parallel non-glycated control incubated under similar conditions indicated that amyloid formation and associated changes were specific for ribosylation and not driven by thermal denaturation due to incubation at 37 °C. Functionality of the glycated protein was significantly altered as probed by Isothermal Titration Calorimetry using polyphenols as substrates. The studies demonstrated that glycation driven globular amyloids form and persist as transient intermediates during formation of misfolded glycated adducts. To the best of our knowledge, the present study is the first systematic attempt to understand glycation associated changes in a protein and provides important insights towards designing therapeutics for arresting dietary sugar induced amyloid formation.

18.
Mamm Genome ; 31(7-8): 252-262, 2020 08.
Article in English | MEDLINE | ID: mdl-32851488

ABSTRACT

Type 2 diabetes mellitus (T2DM) accompanied by hyperlipidemia confers higher risk for diabetes as well as cardiovascular diseases. NF-κB is actively involved in generating low-grade inflammation and oxidative stress triggering the development of diabetic complications. In this study, we have attempted to investigate the association between NF-κB1 functional promoter polymorphism-94 ATTG insertion/deletion (rs28362491) with inflammatory markers in developing diabetes-linked dyslipidemia. We performed a case-control study in a total of 401 individuals belonging to three categories such as Type 2 diabetes with dyslipidemia, Type 2 diabetes without dyslipidemia, and normal healthy controls. Experiments were carried out using genotyping, real-time PCR, and western blot. Pearson's correlation, analysis of variance, and logistic regression were utilized for statistical analysis. As per genetic association conducted in this study the SNP rs28362491 showed significant allelic and genotypic associations (Allelic: OR = 1.374, CI 0.9797-1.927, p = 0.003, and Genotypic in dominant model: OR = 1.77, CI 1.04-2.99, p = 0.002) with the risk of diabetes and associated dyslipidemia. The -94 ATTG insertion/insertion (ins/ins) genotype was associated with significantly increased level of serum TNF-α (p = 0.002), serum IL-6 (p = 0.067) in diabetes-induced dyslipidemia. Multiple linear regression analysis identifies independent correlation of Total cholesterol, HDL, LDL, TNF-α, and rs28362491 ATTG ins/ins with triglyceride in diabetic dyslipidemic condition. T2DM with dyslipidemia having ins/ins genotype showed significant increased expression of pro-inflammatory cytokines such as TNF-α, IL-6, and activation of NF-κB. Our study reports that individuals with ATTG insertion allele and ATTG ins/ins genotype at NF-κB1 promoter regulatory gene predicts the risk and severity of T2DM-linked dyslipidemia.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/genetics , Dyslipidemias/etiology , Genetic Predisposition to Disease , NF-kappa B/genetics , Polymorphism, Genetic , Promoter Regions, Genetic , Alleles , Biomarkers , Cytokines/metabolism , Diabetes Mellitus, Type 2/metabolism , Dyslipidemias/blood , Dyslipidemias/metabolism , Gene Expression , Genotype , Humans , INDEL Mutation , Inflammation Mediators/metabolism , Models, Biological , NF-kappa B/metabolism
19.
Cell Biol Int ; 44(8): 1628-1639, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32237184

ABSTRACT

Autophagy plays an important role in the pathophysiology of type 2 diabetes (T2D). Metformin is the most common antidiabetic drug. The main objective of this study was to explore the molecular mechanism of metformin in starvation-induced autophagy in peripheral blood mononuclear cells (PBMCs) of type 2 diabetic patients. PBMCs were isolated from 10 diabetic patients and 7 non-diabetic healthy volunteers. The autophagic puncta and markers were measured with the help of monodansylcadaverine staining and western blot. Additionally, transmission electron microscopy was also performed. No significant changes were observed in the initial autophagy marker protein levels in PBMCs of T2D after metformin treatment though diabetic PBMCs showed a high level of phospho-mammalian target of rapamycin, p62 and reduced expression of phospho-AMP-activated protein kinase and lysosomal membrane-associated protein 2, indicating a defect in autophagy. Also, induction of autophagy by tunicamycin resulted in apoptosis in diabetic PBMCs as observed by caspase-3 cleavage and reduced expression of Bcl2. Inhibition of autophagy by bafilomycin rendered consistent expression of p62 indicating a defect in the final process of autophagy. Further, electron microscopic studies also confirmed massive vacuole overload and a sign of apoptotic cell death in PBMCs of diabetic patients, whereas metformin treatment reduced the number of autophagic vacuoles perhaps by lysosomal fusion. Thus, our results indicate that defective autophagy in T2D is associated with the fusion process of lysosomes which could be overcome by metformin.


Subject(s)
Autophagy/drug effects , Diabetes Mellitus, Type 2/physiopathology , Hypoglycemic Agents/pharmacology , Leukocytes, Mononuclear/drug effects , Metformin/pharmacology , Aged , Apoptosis , Autophagosomes/physiology , Cells, Cultured , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Endoplasmic Reticulum Stress , Female , Humans , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/physiology , Leukocytes, Mononuclear/ultrastructure , Lysosomes/physiology , Male , Membrane Fusion/drug effects , Middle Aged
20.
Bioconjug Chem ; 31(5): 1301-1306, 2020 05 20.
Article in English | MEDLINE | ID: mdl-32250101

ABSTRACT

Herein, conjugation of the amyloid-ß (Aß) peptide fragment, Lys-Leu-Val-Phe-Phe (KLVFF, fragment of Aß16-20), with an unsymmetrical near-infrared (NIR) cyanine-5 (Cy-5) chromophore is achieved using microwave-assisted solid phase synthesis on 2-chlorotrityl chloride resin. Selective mitochondria tracking and staining in human carcinoma cells are accomplished by the KLVFF/Cy-5 conjugate containing triphenylphosphonium functionality, and this is compared to a control molecule KLVFF/Cy-5c. Mitochondrial target specificity of KLVFF/Cy-5 is established by the colocalization assay using mitochondria selective probe MitoTracker Red, which is monitored by confocal laser scanning microscope and shows a high Pearson's correlation coefficient. The KLVFF/Cy-5 conjugate has high photostability, NIR absorption/emission, high molar extinction coefficient, narrow absorption/emission band, high fluorescence lifetime, and high fluorescence quantum yield. Moreover, mitochondria targeting KLVFF/Cy-5 conjugate reaches the critical aggregation concentration inside the mitochondria of cancer cells due to the strong negative inner mitochondrial membrane potential [(ΔΨm)cancer -220 mV] and self-assembles to form amyloid fibrils at the target site, which is responsible for the mitochondrial dysfunction and cytotoxicity. Annexin V-FITC/PI apoptosis detection assay is used to determine the signal pathway of mitochondria targeted cellular dysfunction.


Subject(s)
Infrared Rays , Mitochondria/metabolism , Mitochondria/pathology , Molecular Imaging/methods , Peptides/chemistry , Cell Line, Tumor , Humans , Membrane Potential, Mitochondrial , Microscopy, Confocal , Peptides/metabolism , Protein Conformation, beta-Strand , Signal Transduction
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