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1.
Bioorg Med Chem ; 52: 116526, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34839157

ABSTRACT

The HIV-1 invasion is initiated with the interaction of viral glycoprotein gp120 and cellular receptor CD4. The binding mechanism reveals two major hotspots involved in gp120-CD4 interaction. The first one is a hydrophobic cavity (Phe43 cavity) on gp120 capped with phenyl ring of phe43CD4 and the second is the electrostatic interaction between positive charge of Arg59CD4 and negative charge of Asp368gp120. Targeting these hotspots, small molecules for entry inhibition and HIV-1 neutralization were designed and tested. In the process, pyrimidine derivatives were identified as potent molecules to intercept gp120-CD4 binding by targeting both the hotspots. Herein, the synthesis, characterization of 1,2,3,4-Tetrahydropyrimidine derivatives, and biological evaluation on 93IN101, a clade C virus are presented. The paper presents a novel set of entry inhibitors to target dual hotspots on gp120 to inhibit protein-protein interactions.


Subject(s)
Anti-HIV Agents/pharmacology , Drug Design , HIV Fusion Inhibitors/pharmacology , HIV-1/drug effects , Pyrimidinones/pharmacology , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/chemistry , Dose-Response Relationship, Drug , HIV Envelope Protein gp120 , HIV Fusion Inhibitors/chemical synthesis , HIV Fusion Inhibitors/chemistry , HIV-1/metabolism , Humans , Microbial Sensitivity Tests , Molecular Structure , Pyrimidinones/chemical synthesis , Pyrimidinones/chemistry , Structure-Activity Relationship
2.
Bioorg Chem ; 116: 105313, 2021 11.
Article in English | MEDLINE | ID: mdl-34517280

ABSTRACT

The third variable loop region (V3 loop) on gp120 plays an important role in cellular entry of HIV-1. Its interaction with the cellular CD4 and coreceptors is an important hallmark in facilitating the bridging by gp41 and subsequent fusion of membranes for transfer of viral genetic material. Further, the virus phenotype determines the cell tropism via respective co- receptor binding. Thus, coreceptor binding motif of envelope is considered to be a potent anti-viral drug target for viral entry inhibition. However, its high variability in sequence is the major hurdle for developing inhibitors targeting the region. In this study, we have used an in silico Virtual Screening and "Fragment-based" method to design small molecules based on the gp120 V3 loop interactions with a potent broadly neutralizing human monoclonal antibody, 447-52D. From the in silico analysis a potent scaffold, 1,3,5-triazine was identified for further development. Derivatives of 1,3,5-triazine with specific functional groups were designed and synthesized keeping the interaction with co-receptor intact. Finally, preliminary evaluation of molecules for HIV-1 inhibition on two different virus strains (clade C, clade B) yielded IC50 < 5.0 µM. The approach used to design molecules based on broadly neutralizing antibody, was useful for development of target specific potent antiviral agents to prevent HIV entry. The study reported promising inhibitors that could be further developed and studied.


Subject(s)
Anti-HIV Agents/pharmacology , Broadly Neutralizing Antibodies/pharmacology , Drug Design , HIV Envelope Protein gp120/antagonists & inhibitors , HIV-1/drug effects , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/chemistry , Broadly Neutralizing Antibodies/chemistry , Dose-Response Relationship, Drug , HIV Envelope Protein gp120/metabolism , HIV-1/metabolism , Humans , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship
3.
Arch Biochem Biophys ; 633: 78-84, 2017 11 01.
Article in English | MEDLINE | ID: mdl-28669856

ABSTRACT

Topoisomerase IIß is a type II DNA topoisomerase that was reported to be expressed in all mammalian cells but abundantly expressed in cells that have undergone terminal differentiation to attain a post mitotic state. Enzymatically it catalyzes ATP-dependent topological changes of double stranded DNA, while as a protein it was reported to be associated with several factors in promoting cell growth, migration, DNA repair and transcription regulation. The cellular roles of topoisomerase IIß are very less understood compared to its counterpart topoisomerase IIα. This review discusses origin of Topoisomerase II beta, its structure, activities reported in vitro and in vivo along with implications in cellular processes namely transcription, DNA repair, neuronal development, aging, HIV-infection and cancer.


Subject(s)
Aging/genetics , DNA Repair , DNA Topoisomerases, Type II/genetics , DNA-Binding Proteins/genetics , DNA/genetics , Neurogenesis/genetics , Transcription, Genetic , Aging/metabolism , Animals , Cell Cycle/genetics , Cell Differentiation , Cell Movement , DNA/chemistry , DNA/metabolism , DNA Topoisomerases, Type II/chemistry , DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , HIV Infections/enzymology , HIV Infections/genetics , HIV Infections/pathology , HIV Infections/virology , Humans , Models, Molecular , Neoplasms/enzymology , Neoplasms/genetics , Neoplasms/pathology , Neurons/cytology , Neurons/enzymology , Protein Structure, Tertiary
4.
Pharm Res ; 34(2): 257-268, 2017 02.
Article in English | MEDLINE | ID: mdl-27928647

ABSTRACT

PURPOSE: To enhance efficacy, bioavailability and reduce toxicity of first-line highly active anti-retroviral regimen, zidovudine + efavirenz + lamivudine loaded lactoferrin nanoparticles were prepared (FLART-NP) and characterized for physicochemical properties, bioactivity and pharmacokinetic profile. METHODS: Nanoparticles were prepared using sol-oil protocol and characterized using different sources such as FE-SEM, AFM, NanoSight, and FT-IR. In-vitro and in-vivo studies have been done to access the encapsulation-efficiency, cellular localization, release kinetics, safety analysis, biodistribution and pharmacokinetics. RESULTS: FLART-NP with a mean diameter of 67 nm (FE-SEM) and an encapsulation efficiency of >58% for each drug were prepared. In-vitro studies suggest that FLART-NP deliver the maximum of its payload at pH5 with a minimum burst release throughout the study period with negligible toxicity to the erythrocytes plus improved in-vitro anti-HIV activity. FLART-NP has improved the in-vivo pharmacokinetics (PK) profiles over the free drugs; an average of >4fold increase in AUC and AUMC, 30% increase in the Cmax, >2fold in the half-life of each drug. Biodistribution data suggest that FLART-NP has improved the bioavailability of all drugs with less tissue-related inflammation as suggested with histopathological evaluation CONCLUSIONS: The triple-drug loaded nanoparticles have various advantages against soluble (free) drug combination in terms of enhanced bioavailability, improved PK profile and diminished drug-associated toxicity.


Subject(s)
Anti-Retroviral Agents/chemistry , Benzoxazines/chemistry , HIV Infections/drug therapy , Lactoferrin/chemistry , Lamivudine/chemistry , Nanoparticles/chemistry , Zidovudine/chemistry , Alkynes , Animals , Anti-Retroviral Agents/administration & dosage , Anti-Retroviral Agents/pharmacokinetics , Benzoxazines/administration & dosage , Benzoxazines/pharmacokinetics , Cell Line, Tumor , Cyclopropanes , Drug Combinations , Female , HIV Infections/metabolism , HIV-1/drug effects , Half-Life , Humans , Lactoferrin/administration & dosage , Lactoferrin/pharmacokinetics , Lamivudine/administration & dosage , Lamivudine/pharmacokinetics , Male , Nanoparticles/administration & dosage , Nanoparticles/metabolism , Rats , Rats, Wistar , Tissue Distribution/physiology , Zidovudine/administration & dosage , Zidovudine/pharmacokinetics
5.
Arch Biochem Biophys ; 593: 90-7, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26876283

ABSTRACT

TopoisomeraseIIß, an isoform of type II topoisomerase, was found to be functional in various viral infections. Its plausible role in HIV life cycle was also suggested earlier, but not clearly established. In the present study, we have investigated the role of TopoIIß in HIV-1 infection by its gain and loss of function. Overexpression of TopoIIß lead to an increase in viral replication, resulting in enhanced virion production. HIV-1 replication was impaired when TopoIIß was down regulated by siRNA and inhibited by ICRF-193 and merbarone. The role of TopoIIß in HIV-1 transcription was shown through its interaction with Tat and recruitement to long terminal repeat (LTR) region by co-immunoprecipitation and ChIP assays. Involvement of TopoIIß in transactivation of HIV-1 LTR was confirmed by luciferase assay in reporter cell line, TZM bl and also by transfection of reporter exogenously. It was also observed that LTR transactivation commensurated with the expression of TopoIIß in the presence of Tat. In addition, a decreased viral gene expression on treatment with merbarone exemplifies the importance of catalytic activity of TopoIIß in viral replication. These observations indicate that TopoIIß is involved in the cascade of coactivator complexes that are recruited to LTR for regulation of HIV-1 transcription.


Subject(s)
DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/metabolism , HIV-1/genetics , Antigens, Nuclear/metabolism , Cell Line, Tumor , HEK293 Cells , HIV Long Terminal Repeat , HIV-1/metabolism , Humans , Ku Autoantigen , Poly (ADP-Ribose) Polymerase-1 , Poly(ADP-ribose) Polymerases/metabolism , Transcriptional Activation , Virus Replication , tat Gene Products, Human Immunodeficiency Virus/metabolism
6.
Biochim Biophys Acta ; 1834(4): 780-90, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23360764

ABSTRACT

Early pregnancy associated protein-1 (Epap-1), a 90kDa glycoprotein present in first trimester placental tissue, inhibits HIV-1 entry through interaction with HIV-1 gp120 at V3 and C5 regions. In the present study, we have identified the specific 32 mer region of Epap-1 that can interact with V3 loop. This was achieved by docking between Epap-1 molecular model and gp120 and studying the interaction of peptides with gp120 in vitro. Out of four peptides analyzed, two peptides (P-2 and P-3) showed significant interaction with V3 domain (N=8; N=7) of gp120. In the studies conducted using soluble gp120 and virus, peptide P-2 has shown conserved interaction at V3 loop regions recognized by 257D and F425 antibodies and higher anti-viral activity. Also, P-2 inhibited cell fusion mediated dye transfer between gp120 expressing HL2/3 and CD4 expressing Sup T1 cells suggesting its inhibition of viral entry, which is further confirmed by its action on HIV infection mediated by Tat activated beta gal expression in TZM-bl cells. Further optimization of P-2 peptide showed that the anti-viral activity and gp120 interaction residues lie in the N-terminal region of the peptide. These results together suggest that P-2 inhibits viral entry through specific interaction at V3 loop region.


Subject(s)
Glycoproteins , HIV Envelope Protein gp120 , HIV-1/drug effects , Peptides/pharmacology , Pregnancy Proteins , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/virology , Female , Glycoproteins/chemistry , Glycoproteins/genetics , HIV Envelope Protein gp120/chemistry , HIV Envelope Protein gp120/genetics , HIV Infections/drug therapy , Humans , Models, Molecular , Molecular Docking Simulation , Peptides/chemistry , Pregnancy , Pregnancy Proteins/chemistry , Pregnancy Proteins/genetics , Protein Binding
7.
Placenta ; 152: 39-52, 2024 07.
Article in English | MEDLINE | ID: mdl-38788480

ABSTRACT

INTRODUCTION: Several factors influence transmission of 2019-nCoV from mother to fetus during pregnancy, thus the dynamics of vertical transmission is unclear. The role of cellular protective factors, namely a 90 KDa glycoprotein, Early pregnancy-associated protein (Epap-1), expressed by placental endothelial cells in women during early pregnancy would provide an insight into role of placental factors in virus transmission. Since viral spike protein binding to the ACE2 receptors of the host cells promotes virus invasion in placental tissue, an analysis of effects of Epap-1 on the Spike-ACE2 protein binding was studied. METHODS: Epap-1 was isolated from MTP placental tissue. Molecular interaction of Epap-1 and variants of the spike was analyzed in silco. The interaction of Epap-1 with Spike and RBD were analyzed using ELISA and immunofluorescence studies. RESULTS: The results in silico showed an interaction of Epap-1 with S-protein at RBD region involving K417, Y449, Y453, Y456, Y473, Q474, F486, Q498, N501 residues of spike with Y61, F287, I302, N303, N305, S334, N465, G467, N468 residues of Epap-1 leading to interference of S-protein and ACE2 interaction [1]. Further, the interaction is conserved among the variants. The studies in vitro confirm that Epap-1 affects S protein-ACE2 and RBD- ACE2 binding, thus suggesting that during early pregnancy, SARS CoV-2 infection may be protected by Epap-1 protein present in placental tissue. The results were further confirmed by pseudovirus expressing Spike and RBD in an infection assay. DISCUSSION: Epap-1 interferes with Spike and RBD interaction with ACE2, suggesting a possible mechanism of the antiviral environment during pregnancy.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Infectious Disease Transmission, Vertical , Placenta , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Female , Humans , Pregnancy , Angiotensin-Converting Enzyme 2/metabolism , Betacoronavirus/metabolism , Coronavirus Infections/transmission , Coronavirus Infections/metabolism , Coronavirus Infections/virology , COVID-19/transmission , COVID-19/metabolism , Pandemics , Peptidyl-Dipeptidase A/metabolism , Placenta/metabolism , Placenta/virology , Pneumonia, Viral/metabolism , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , Pregnancy Complications, Infectious/metabolism , Pregnancy Complications, Infectious/virology , Pregnancy Proteins/metabolism , Protein Binding , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism
8.
Arch Biochem Biophys ; 532(2): 91-102, 2013 Apr 15.
Article in English | MEDLINE | ID: mdl-23399433

ABSTRACT

HIV-1 reverse transcription (RTn) involves synthesis of double strand DNA (dsDNA) from viral genomic RNA. Topoisomerase II (Topo II) alpha and beta maintains topological reorganization of dsDNA regions and catalytic inhibition of these isoforms repressed viral replicative cycle. Present study is aimed to understand the role of Topo II isoforms in HIV-1 early replication. Topo IIα and ß showed differential expression in SupT1 cells and PBMCs during early hours of HIV-1 infection where Topo IIα expression increased after 4h, while Topo IIß showed relatively higher expression at 1 and 4h. In Topo IIα and/or ß down regulated cells, transcription of viral genes gag, pol and env as well as proviral DNA synthesis was abolished. In Topo IIα and/or ß down regulated cells, strong stop DNA synthesis was unaffected while other downstream events of reverse transcription such as first strand transfer, full length minus strand synthesis, and second strand transfer were completely inhibited, which affects HIV-1 replication. Further, co-localization of Topo II isoforms with HIV-1 reverse transcriptase was observed in SupT1 cells and PBMCs by immunofluorescence. These results collectively suggest a role of Topo II isoforms during HIV-1 RTn probably by promoting the alignment of viral RNA-DNA hybrids.


Subject(s)
DNA Topoisomerases, Type II/metabolism , HIV Infections/enzymology , HIV-1/physiology , Host-Pathogen Interactions , Cell Line , Cells, Cultured , DNA Topoisomerases, Type II/analysis , DNA Topoisomerases, Type II/genetics , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Viral , Gene Knockdown Techniques , HIV Infections/genetics , HIV Infections/metabolism , HIV Reverse Transcriptase/analysis , HIV Reverse Transcriptase/metabolism , Humans , Leukocytes, Mononuclear/virology , Protein Isoforms/analysis , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Small Interfering/genetics , Virus Replication
9.
BMC Complement Altern Med ; 13: 53, 2013 Mar 02.
Article in English | MEDLINE | ID: mdl-23452983

ABSTRACT

BACKGROUND: The use of traditional medicine at the primary health care level is widespread and plant-based treatments are being recommended for curing various diseases by traditional medical practitioners all over the world. The phytochemicals present in the fruits, vegetables and medicinal plants are getting attention day-by-day for their active role in the prevention of several human diseases. Abrus precatorius is a widely distributed tropical medicinal plant with several therapeutic properties. Therefore in the present study, A. precatorius leaf extracts were examined for their antioxidant and cytotoxic properties in vitro in order to discover resources for new lead structures or to improve the traditional medicine. METHODS: In this study, antioxidant and antiproliferative properties of the different leaf extracts (hexane, ethyl acetate, ethanol and water) from A. precatorius were investigated along with the quantification of the polyphenol and flavonoid contents. The ability of deactivating free radicals was extensively investigated with in vitro biochemical methods like DPPH(∙), (∙)OH, NO, SO(2-) scavenging assays and inhibition capability of Fe(II)-induced lipid peroxidation. Furthermore, antiproliferative activities using different human cancer cell lines and primary cell line was carried out by MTT method. RESULTS: Total phenolic content and total flavonoid content of the extracts were found in the range of 1.65 ± 0.22 to 25.48 ± 0.62 GAE mg/g dw and 6.20 ± 0.41 to 17.16 ± 1.04 QE mg/g dw respectively. The experimental results further revealed that A. precatorius extracts showed strong antiradical properties, capable to chelate Fe(2+) and possess good inhibition ability of lipid peroxidation. In addition, as a first step towards the identification of phytoconstituents endowed with potent chemopreventive activities, we evaluated the inhibitory effects of A. precatorius extracts on the proliferation of four different human tumour cell lines such as human colon adenocarcinoma cells (Colo-205), human retinoblastoma cancer cells (Y79), human hepatocellular carcinoma cells (HepG2) and Leukemia cells (SupT1). Ethanol extract (APA) and ethyl acetate extract (APE) of A. precatorius had apparent capabilities of inhibiting the survival of tested human cancer cell lines. Moreover, it was observed that the A. precatorius extracts did not inhibit the growth of mice peritoneal macrophages, thus confirming that plants extracts are selective against the cancer cell lines. CONCLUSION: This work provides a scientific support for the high antioxidant and antiproliferative activity of this plant and thus it may find potential applications in the treatment of the diseases caused by ROS. Further studies are needed to confirm in vivo anti-tumorgenicity and subsequent chemical characterization of the active molecule(s).


Subject(s)
Abrus/chemistry , Antineoplastic Agents, Phytogenic/therapeutic use , Antioxidants/therapeutic use , Neoplasms/drug therapy , Phytotherapy , Plant Extracts/therapeutic use , Polyphenols/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Antioxidants/pharmacology , Flavonoids/analysis , Free Radicals/metabolism , Hep G2 Cells , Humans , Lipid Peroxidation/drug effects , Macrophages/drug effects , Mice , Phenols/analysis , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves , Polyphenols/analysis , Polyphenols/pharmacology
10.
Eur J Med Chem ; 259: 115623, 2023 Nov 05.
Article in English | MEDLINE | ID: mdl-37473689

ABSTRACT

Topoisomerase II (TopoII) is a critical component of HIV-1 integration, proviral DNA synthesis, and reverse transcription. During HIV-1 infection, the TopoIIßkinase (TopoIIßKHIV-1) phosphorylates TopoIIß. Our earlier research demonstrated that the pyridine scaffold has potent anti-HIV-1 activity by specifically inhibiting TopoIIßKHIV-1 activity. 3D QSAR results showed the presence of molecular features for interaction with TopoIIßKHIV-1 requiring chemically induced proximity for potential interaction. In this study, the chalcone and methyl groups were added to the pyridine scaffold's core to achieve the desired proximity length between the pyridine scaffold and charged centers, which resulted in an inhibitory activity against TopoIIßKHIV-1 and viral replication. According to the findings, the TopoIIßKHIV-1activity was inhibited by the inclusion of the pyridine scaffold with the chalcone group, leading to better anti-HIV-1 activity. The water-soluble methylated pyridinium chalcones' showed significant TopoIIßKHIV-1 antagonism, anti-HIV-1 activity (from IC50 > 500 nM to ID50 25 nM), and reduced cytotoxicity (CC50 = 2 mM). These activities could be associated with the charge on the pyridine and extended proximity. Therefore, it is clear that within the scope of this work, altering the proximity length and charge centers of pyridine molecules are critical for the design and development of effective anti-HIV-1 leads, specifically targeting TopoIIßKHIV-1.


Subject(s)
Anti-HIV Agents , Chalcone , DNA Replication , DNA Topoisomerases, Type II/metabolism , Pyridines/pharmacology , Pyridines/chemistry , Quantitative Structure-Activity Relationship , Anti-HIV Agents/chemistry
11.
Cancer Chemother Pharmacol ; 91(5): 375-387, 2023 05.
Article in English | MEDLINE | ID: mdl-36977771

ABSTRACT

BACKGROUND: Tumor metastasis is promoted by an immunosuppressive environment. Lactoferrin (Lf) is known to regulate immunological activity in tumor cells and inhibit processes associated with tumor metastasis. A delivery of lactoferrin with docetaxel (DTX) in prostate cancer cells in the form of DTX-loaded lactoferrin nanoparticles (DTX-LfNPs) would provide a dual activity wherein the lactoferrin affects metastasis and DTX chemotherapeutically inhibits mitosis and cell division. METHODS: DTX-LfNPs were prepared using sol-oil chemistry, and particles were characterized using transmission electron microscopy. Antiproliferation activity was analyzed in prostate cancer Mat Ly Lu cells. The target localization and efficacy of DTX-LfNPs were studied in an orthotopic prostate cancer induced by Mat Ly Lu cells in a rat model. Biomarkers were estimated using ELISA and biochemical reactions. RESULTS: DTX was loaded in pure Lf nanoparticles without involving any chemical modification and conjugation, thus when these nanoparticles are delivered in cancer cells both DTX and Lf will be present in biologically active forms. DTX-LfNps exhibit a spherical morphology of dimension of 60 ± 10 nm with DTX Encapsulation Efficiency of 62.06 ± 4.07%. Competition experiments using soluble Lf confirm that DTX-LfNPs enter prostate cancer cells through the Lf receptor. DTX-LfNPs exhibit an improved anti-proliferative activity by 2.5 times compared to DTX. Further, analysis of the bioavailability of the drug in the prostate showed that DTX-LfNPs increased drug bioavailability in the prostate by two times more than the DTX. The analysis of efficacy in the Mat Ly Lu cells-induced orthotopic prostate cancer model showed that DTX-LfNPs significantly enhanced the anti-cancer activity compared to DTX in terms of regression of weight and volume of prostate tissue, the efficacy was confirmed by histochemical analysis. Lf provides synergistic activity along with DTX in inhibiting metastasis as assessed by the reduction of lactate dehydrogenase, alkaline phosphatase, TNF alpha, and IFNγ. LfNPs facilitate higher DTX localization along with Lf-mediated protection from DTX-associated toxicity to neutrophils and kidneys as assessed by C-reactive protein, creatinine, and uric acid. Thus, DTX LfNPs show a dual action by enhancing DTX bioavailability in prostate along with Lf-mediated suppression of metastasis as well as DTX-associated toxicity. CONCLUSION: In conclusion, DTX-LfNPs enhance the bioavailability of DTX in the prostate along with Lf-assisted improvement in inhibition of tumor metastasis and drug-associated toxicity.


Subject(s)
Antineoplastic Agents , Nanoparticles , Prostatic Neoplasms , Humans , Male , Rats , Animals , Docetaxel , Lactoferrin/pharmacology , Lactoferrin/chemistry , Lactoferrin/metabolism , Prostatic Neoplasms/drug therapy , Nanoparticles/chemistry , Cell Line, Tumor , Antineoplastic Agents/adverse effects , Antineoplastic Agents/chemistry , Drug Carriers/chemistry
12.
Arch Biochem Biophys ; 516(2): 128-37, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-22019940

ABSTRACT

In the present study, the activity of Topoisomerase IIß (TopoIIß) is evaluated during peroxide induced double stranded DNA breaks (DSBs) repair in primary neurons. The results showed that the TopoIIß levels were enhanced during recovery from peroxide mediated damage (PED) along with Ku70, PARP-1, pol beta, and WRN helicase. Furthermore, siRNA mediated knock-down of TopoIIß in primary neurons conferred enhanced susceptibility to PED in neurons. DSBs in neurons are repaired through two pathways, one promoted by Ku70, while the other is by PARP-1 dependent manner. Participation of TopoIIß in both pathways was assessed by analysis of the interaction of TopoIIß with Ku70 and PARP-1 using co-immunoprecipitation experiments in extracts of neurons under peroxide treatment and recovery. The results of these studies showed a strong interaction of TopoIIß with Ku70 as well as PARP-1 suggesting that TopoIIß is associated both in Ku70 and PARP-dependent pathways in DSBs repair in primary neurons. The study has thus established that TopoIIß is an essential component in DSBs repair in primary neurons in both Ku70 and PARP-1 dependent pathways. We suppose that the interaction of TopoIIß may provide stabilization of the repair complex, which may assist in maintenance of tensional integrity in genomic DNA.


Subject(s)
Antigens, Nuclear/chemistry , Antigens, Nuclear/metabolism , DNA Repair/physiology , DNA Topoisomerases, Type II/chemistry , DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Neurons/metabolism , Poly(ADP-ribose) Polymerases/chemistry , Poly(ADP-ribose) Polymerases/metabolism , Animals , Cells, Cultured , Cerebellum/cytology , Cerebellum/metabolism , DNA Breaks, Double-Stranded , DNA Topoisomerases, Type II/genetics , DNA-Binding Proteins/antagonists & inhibitors , DNA-Binding Proteins/genetics , Gene Knockdown Techniques , Ku Autoantigen , Poly (ADP-Ribose) Polymerase-1 , Protein Interaction Domains and Motifs , Protein Stability , RNA, Small Interfering/genetics , Rats
13.
BMC Complement Altern Med ; 11: 64, 2011 Aug 17.
Article in English | MEDLINE | ID: mdl-21849051

ABSTRACT

BACKGROUND: Abelmoschus moschatus Medik. leaves and seeds are considered as valuable traditional medicine. The aromatic seeds of this plant are aphrodisiac, ophthalmic, cardio tonic, antispasmodic and used in the treatment of intestinal complaints and check queasiness. To give a scientific basis for traditional usage of this medicinal plant, the seed and leaf extracts were evaluated for their antioxidant, free radical scavenging, antimicrobial and antiproliferative activities. METHODS: In this study, antioxidant, antimicrobial and antiproliferative activities of A. moschatus extracts were evaluated in a series of in vitro assay involving free radicals, reactive oxygen species and their IC50 values were also determined. The antioxidant activities of the seed and leaf extracts of A. moschatus were determined by total antioxidant, DPPH, and ferrous reducing antioxidant property (FRAP) methods. In addition, the antiproliferative activity was also evaluated using colorectal adenocarcinoma and retinoblastoma human cancer cell lines. Moreover, six bacterial reference strains, two gram-positive (Bacillus subtilis and Staphylococcus aureus), four gram-negative (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Salmonella enterica paratyphi) and one fungal strain (Candida albicans) were used to evaluate its antimicrobial activity. RESULTS: The results from this study showed that the antioxidant activities of A. moschatus as determined by the total phenol, flavonoids, total antioxidant and FRAP methods were higher in leaf than that of the seed extracts. On the other hand, the aqueous overnight seed extract (AMS-I) has shown significant radical scavenging activity as in 1, 1- Diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide, hydroxyl radical, superoxide and lipid peroxidation as compared to other seed and leaf extracts. The AMS-I and AML-IV have shown activity against six and seven microorganisms respectively. Simulteneously, AMS-IV and AML-IV have demonstrated potential antiproliferative activity against two human cell lines - Colorectal adenocarcinoma (COLO-205) and retinoblastoma (Y79). CONCLUSION: The seed and leaf extracts of A. moschatus possess significant antioxidant activity and could serve as free radical inhibitors or scavenger, or substitute, probably as primary antioxidants. The plant possesses moderate antibacterial activity against bacterial strains used in this study. Hydroalcoholic seed and leaf extracts also exhibited antiproliferative activity against two human cancer cell lines. A. moschatus may therefore, be a good candidate for functional foods as well as pharmaceutics.


Subject(s)
Abelmoschus/chemistry , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Antioxidants/therapeutic use , Neoplasms/drug therapy , Phytotherapy , Plant Extracts/therapeutic use , Antineoplastic Agents, Phytogenic/pharmacology , Antioxidants/pharmacology , Bacteria/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Free Radical Scavengers/pharmacology , Free Radical Scavengers/therapeutic use , Humans , Plant Extracts/pharmacology , Plant Leaves , Polyphenols/pharmacology , Polyphenols/therapeutic use , Seeds
14.
Mol Biotechnol ; 63(8): 732-745, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33993458

ABSTRACT

Topoisomerase II beta (Topo IIß) is one of the two isoforms of type II topoisomerases present in higher eukaryotes. This 180 kDa nuclear protein involves in different cellular processes like transcription, recombination, etc., apart from its normal topological functions. Previously, we have reported the association of this isoform along with the other isoform topoisomerase II alpha (Topo IIα) with HIV-1 reverse transcription complex and the downregulation of Topo IIß expression resulted in incomplete reverse transcription. In this study, we have tested the Topo IIß specific siRNA delivery using protein nanoparticles prepared with c-terminal domine of transferrin (c-ter) for the first time. Results show that, c-ter nanoparticles resemble apotransferrin nanoparticles in drug holding capability and drug delivery but with small in size. Topo IIß specific siRNA delivered in the form of c-ter nanoformulation resulted in knockdown of Topo IIß expression for the prolonged periods and which intern resulted in decreased viral replication of HIV-1.


Subject(s)
Apoproteins/chemistry , DNA Topoisomerases, Type II/genetics , HIV-1/drug effects , Nanoparticles/chemistry , RNA, Small Interfering/pharmacology , Transferrin/chemistry , Virus Replication/drug effects , Apoproteins/genetics , Apoproteins/metabolism , Cell Line , Drug Delivery Systems , Drug Liberation , Gene Silencing , HIV-1/physiology , Humans , Lipids/chemistry , Protein Domains , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics , Receptors, Transferrin/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Transferrin/genetics , Transferrin/metabolism
15.
Nanomedicine (Lond) ; 16(7): 569-586, 2021 03.
Article in English | MEDLINE | ID: mdl-33660529

ABSTRACT

Aim: We report here the development of tenofovir- and curcumin-loaded lactoferrin nanoparticles (TCNPs) as an HIV-microbicide. Materials & methods: TCNPs were subjected to various physicochemical characterization experiments, followed by in vitro and in vivo experiments to assess their efficacy. Results: TCNPs had a diameter of 74.31 ± 2.56 nm with a gross encapsulation of more than 61% for each drug. Nanoparticles were effective against HIV-1 replication, with an IC50 of 1.75 µM for curcumin and 2.8 µM for tenofovir. TCNPs provided drug release at the application site for up to 8-12 h, with minimal leakage into the systemic circulation. TCNPs showed spermicidal activity at ≥200 µM and induced minimal cytotoxicity and inflammation in the vaginal epithelium as revealed by histopathological and ELISA studies. Conclusion: We demonstrated that TCNPs could serve as a novel anti-HIV microbicidal agent in rats. [Formula: see text].


Subject(s)
HIV Infections , HIV-1 , Nanoparticles , Animals , Curcumin , Female , HIV Infections/drug therapy , Lactoferrin , Rats , Tenofovir
16.
Invest Ophthalmol Vis Sci ; 62(14): 13, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34784412

ABSTRACT

Purpose: Cancer stem cells (CSCs) are known to contribute to tumor relapses by virtue of their chemoresistance. With the knowledge that nanoformulations can overcome drug resistance, we evaluated the efficacy and cytotoxicity of clinical-grade carboplatin (CPT)- and etoposide (ETP)-loaded lactoferrin nanoparticles (Lf-Nps) on total, CD133-enriched (non-CSC), and CD133-depleted (CSC) populations of retinoblastoma (Rb) Y79 cells. Methods: Physicochemical properties of drug-loaded Lf-Nps were measured with transmission electron microscopy and attenuated total reflectance-Fourier transform infrared. The encapsulation efficiency, uptake, and release of drug-loaded Lf-Nps were measured using high-performance liquid chromatography and a UV-visible spectrophotometer. Cytotoxicity of the standard and drug-loaded Lf-Nps was evaluated by the MTT assay. Results: The mean (SD) size and encapsulation efficiency of Lf-CPT and Lf-ETP were 61.2 (3.94) nm, 60% and 45.15 (5.85) nm, 38%, respectively, and the drug release efficiency was highest at pH 6. The increased drug uptake and lower release of drug-loaded Lf-Nps were observed in CSC and non-CSC populations compared to their standard forms. The relative increase of drug uptake and sustained intracellular retention of the drug-loaded Lf-Nps compared to standard drugs showed an enhanced cytotoxicity up to 50%, especially in Rb Y79 CSCs (IC50: CPT, 230.3; Lf-CPT, 118.2; ETP, 198.1; and Lf-ETP, 129) compared to non-CSCs. Conclusions: Our study documents an increase in drug uptake, retention, and cytotoxicity of Lf-CPT and Lf-ETP on Y79 CSCs and non-CSCs as compared to their standard drugs in vitro. The reversal of chemoresistance in the CSC population by nanoformulation appears promising with the potential to pave the way for improved targeted therapy and better clinical outcomes.


Subject(s)
Carboplatin/pharmacology , Etoposide/pharmacology , Lactoferrin/chemistry , Nanoparticles/chemistry , Neoplastic Stem Cells/drug effects , Retinal Neoplasms/drug therapy , Retinoblastoma/drug therapy , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacokinetics , Antineoplastic Agents, Phytogenic/pharmacology , Biological Availability , Carboplatin/pharmacokinetics , Chromatography, High Pressure Liquid , Culture Media , Drug Carriers/chemistry , Drug Delivery Systems , Etoposide/pharmacokinetics , Flow Cytometry , Humans , Microscopy, Confocal , Microscopy, Electron, Transmission , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Retinal Neoplasms/metabolism , Retinal Neoplasms/pathology , Retinoblastoma/metabolism , Retinoblastoma/pathology , Spectroscopy, Fourier Transform Infrared
17.
PLoS One ; 16(2): e0246173, 2021.
Article in English | MEDLINE | ID: mdl-33529260

ABSTRACT

We report clinical profile of hundred and nine patients with SARS CoV-2 infection, and whole genome sequences (WGS) of seven virus isolates from the first reported cases in India, with various international travel histories. Comorbidities such as diabetes, hypertension, and cardiovascular disease were frequently associated with severity of the disease. WBC and neutrophil counts showed an increase, while lymphocyte counts decreased in patients with severe infection suggesting a possible neutrophil mediated organ damage, while immune activity may be diminished with decrease in lymphocytes leading to disease severity. Increase in SGOT, SGPT and blood urea suggests the functional deficiencies of liver, heart, and kidney in patients who succumbed to the disease when compared to the group of recovered patients. The WGS analysis showed that these isolates were classified into two clades: I/A3i, and A2a (four according to GISAID: O, L, GR, and GH). Further, WGS phylogeny and travel history together indicate possible transmission from Middle East and Europe. Three S protein variants: Wuhan reference, D614G, and Y28H were identified predicted to possess different binding affinities to host ACE2.


Subject(s)
COVID-19/virology , Genome, Viral , SARS-CoV-2/genetics , Whole Genome Sequencing , Adult , Aged , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/immunology , COVID-19/pathology , Female , Humans , India , Male , Middle Aged , Phylogeny , RNA, Viral/genetics , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism
18.
Am J Physiol Lung Cell Mol Physiol ; 298(5): L616-25, 2010 May.
Article in English | MEDLINE | ID: mdl-20061443

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a progressive and typically fatal lung disease for which no effective therapy has been identified. The disease is characterized by excessive collagen deposition, possibly in response to dysregulated wound healing. Mediators normally involved in would healing induce proliferation of fibroblasts and their differentiation to myofibroblasts that actively secrete collagen. Curcumin, a polyphenolic compound from turmeric, has been shown to exert a variety of biological effects. Effects on IPF and associated cell types remain unclear, however. We accordingly tested the ability of curcumin to inhibit proliferation and differentiation to myofibroblasts by human lung fibroblasts, including those from IPF patients. To further examine the potential usefulness of curcumin in IPF, we examined its ability to reduce fibrosis in bleomycin-treated mice. We show that curcumin effectively reduces profibrotic effects in both normal and IPF fibroblasts in vitro and that this reduction is accompanied by inhibition of key steps in the transforming growth factor-ß (TGF-ß) signaling pathway. In vivo, oral curcumin treatment showed no effect on important measures of bleomycin-induced injury in mice, whereas intraperitoneal curcumin administration effectively inhibited inflammation and collagen deposition along with a trend toward improved survival. Intraperitoneal curcumin reduced fibrotic progression even when administered after the acute bleomycin-induced inflammation had subsided. These results encourage further research on alternative formulations and routes of administration for this potentially attractive IPF therapy.


Subject(s)
Bleomycin/toxicity , Curcumin/pharmacology , Idiopathic Pulmonary Fibrosis/drug therapy , Lung Injury/chemically induced , Lung Injury/drug therapy , Administration, Oral , Animals , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Collagen/metabolism , Curcumin/administration & dosage , Curcumin/pharmacokinetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Humans , Injections, Intraperitoneal , Lung Injury/metabolism , Lung Injury/pathology , Mice , Mice, Inbred C57BL , Phosphorylation , Signal Transduction/drug effects , Smad Proteins/metabolism , Transforming Growth Factor beta/pharmacology
19.
Nanomedicine (Lond) ; 15(21): 2071-2083, 2020 09.
Article in English | MEDLINE | ID: mdl-32779524

ABSTRACT

Lactoferrin, an iron storage protein, is known for its microbicidal activity and its ability to modulate the immune system, mediated through specific interactions with receptors on cell surfaces for internalization. These activities confer a significant versatility to lactoferrin, presenting it as a targeting ligand to disease-bearing cells. Early efforts in developing targeted delivery systems have focused on nano- and microcomposites comprised of metal and polymeric materials. These can be targeted through conjugation or adsorption of lactoferrin to achieve recognition to receptor-expressing cells. More recently, efforts are underway to utilize lactoferrin itself as a medium in loading the therapeutic agent. The functional efficiency of drug-loaded lactoferrin nanoparticles has been evaluated in different disease conditions such as cancer, HIV, Parkinson's disease, etc. This review will present the details of composition and performance of various delivery systems designed and developed using lactoferrin as targeting agent for the treatment of cancer.


Subject(s)
Nanoparticles , Neoplasms , Drug Delivery Systems , Humans , Iron , Lactoferrin/metabolism , Neoplasms/drug therapy
20.
Colloids Surf B Biointerfaces ; 191: 110979, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32276212

ABSTRACT

Intriguing properties and structural dynamics of Lactoferrin have been exploited in numerous applications, including its use as self-assembling, pH sensitive nanoparticles to deliver intended cargo at the disease site. In this study, we explore the possibility of surface modification of Lactoferrin nanoparticles to hone its specificity to target HIV-1 infected cells. Existence of free cysteine groups on Lactoferrin nanoparticles available for reaction with external molecules facilitates conjugation on the surface with Sodium 2-mercaptoethanesulfonate (MES). Conjugation with MES is used to edge a negative charge that can mimic CCR5 and Heparan sulfate (initial point of contact of HIV-1 env to host cell surface) electrostatic charge (Sulfate group). A simple sono-chemical irradiation method was employed for self-assembly of Nanoparticles and for surface modification. The nanoparticles serve dual purpose to abrogate extracellular entry and to target viral enzymes, when loaded with ART drugs. The morphology and size distribution of the formed particles were explored using Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM) and Dynamic Light Scattering. Raman SERS was employed to understand the difference in the protein upon surface modification. The anti-HIV property of the particles was confirmed in-vitro. The modified device demonstrated acceptable nanoparticle properties with controlled release and higher effective concentration in the area of infection.


Subject(s)
Anti-Infective Agents/administration & dosage , Drug Carriers/chemistry , HIV Infections/drug therapy , HIV-1/drug effects , Lactoferrin/administration & dosage , Nanoparticles/administration & dosage , Sulfonic Acids/chemistry , Anti-Infective Agents/chemistry , Cells, Cultured , HIV Envelope Protein gp160/metabolism , HIV Infections/metabolism , HIV Infections/virology , HIV-1/metabolism , Humans , Lactoferrin/chemistry , Nanoparticles/chemistry
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