WorldWideScience

Sample records for anti-filarial drug target

  1. The heme biosynthetic pathway of the obligate Wolbachia endosymbiont of Brugia malayi as a potential anti-filarial drug target.

    Directory of Open Access Journals (Sweden)

    Bo Wu

    Full Text Available BACKGROUND: Filarial parasites (e.g., Brugia malayi, Onchocerca volvulus, and Wuchereria bancrofti are causative agents of lymphatic filariasis and onchocerciasis, which are among the most disabling of neglected tropical diseases. There is an urgent need to develop macro-filaricidal drugs, as current anti-filarial chemotherapy (e.g., diethylcarbamazine [DEC], ivermectin and albendazole can interrupt transmission predominantly by killing microfilariae (mf larvae, but is less effective on adult worms, which can live for decades in the human host. All medically relevant human filarial parasites appear to contain an obligate endosymbiotic bacterium, Wolbachia. This alpha-proteobacterial mutualist has been recognized as a potential target for filarial nematode life cycle intervention, as antibiotic treatments of filarial worms harboring Wolbachia result in the loss of worm fertility and viability upon antibiotic treatments both in vitro and in vivo. Human trials have confirmed this approach, although the length of treatments, high doses required and medical counter-indications for young children and pregnant women warrant the identification of additional anti-Wolbachia drugs. METHODS AND FINDINGS: Genome sequence analysis indicated that enzymes involved in heme biosynthesis might constitute a potential anti-Wolbachia target set. We tested different heme biosynthetic pathway inhibitors in ex vivo B. malayi viability assays and report a specific effect of N-methyl mesoporphyrin (NMMP, which targets ferrochelatase (FC, the last step. Our phylogenetic analysis indicates evolutionarily significant divergence between Wolbachia heme genes and their human homologues. We therefore undertook the cloning, overexpression and analysis of several enzymes of this pathway alongside their human homologues, and prepared proteins for drug targeting. In vitro enzyme assays revealed a approximately 600-fold difference in drug sensitivities to succinyl acetone (SA between

  2. The Wolbachia endosymbiont of Brugia malayi has an active phosphoglycerate mutase: a candidate target for anti-filarial therapies.

    Science.gov (United States)

    Foster, Jeremy M; Raverdy, Sylvine; Ganatra, Mehul B; Colussi, Paul A; Taron, Christopher H; Carlow, Clotilde K S

    2009-04-01

    Phosphoglycerate mutases (PGM) interconvert 2- and 3-phosphoglycerate in the glycolytic and gluconeogenic pathways. A putative cofactor-independent phosphoglycerate mutase gene (iPGM) was identified in the genome sequence of the Wolbachia endosymbiont from the filarial nematode, Brugia malayi (wBm). Since iPGM has no sequence or structural similarity to the cofactor-dependent phosphoglycerate mutase (dPGM) found in mammals, it may represent an attractive Wolbachia drug target. In the present study, wBm-iPGM cloned and expressed in Escherichia coli was mostly insoluble and inactive. However, the protein was successfully produced in the yeast Kluyveromyces lactis and the purified recombinant wBm-iPGM showed typical PGM activity. Our results provide a foundation for further development of wBm-iPGM as a promising new drug target for novel anti-filarial therapies that selectively target the endosymbiont.

  3. Filamentation temperature-sensitive protein Z (FtsZ) of Wolbachia, endosymbiont of Wuchereria bancrofti: a potential target for anti-filarial chemotherapy.

    Science.gov (United States)

    Sharma, Rohit; Hoti, S L; Vasuki, V; Sankari, T; Meena, R L; Das, P K

    2013-03-01

    instar larvae of Culex quinquefasciatus were treated with 0.25mg/ml of albendazole (test) or tetracycline (positive control) in the rearing medium for different intervals and tested for the presence of Wolbachia by FtsZ PCR. All the treated larvae were negative for the presence of the FtsZ band, whereas all the control larvae were positive. The findings of the study, thus indicated that FtsZ is sensitive to albendazole. In view of this albendazole appears to have dual targets; FtsZ in Wolbachia and β-tubulin in W. bancrofti. Further, the functional domain of the gene was assessed for polymorphism among recombinant clones representing 120 W. bancrofti parasites, prevalent across wide geographic areas of India and found to be highly conserved among them. Since it is highly conserved and plays an important role in Wolbachia cell division it appears to be a potential target for anti-filarial chemotherapy development. PMID:23262214

  4. Towards elimination of lymphatic filariasis: social mobilization issues and challenges in mass drug administration with anti-filarial drugs in Tamil Nadu, South India.

    Science.gov (United States)

    Nandha, B; Krishnamoorthy, K; Jambulingam, P

    2013-08-01

    India is a signatory to World Health Assembly resolution for elimination of lymphatic filariasis (LF) and National Health Policy has set the goal of LF elimination by 2015. Annual mass drug administration (MDA) is ongoing in endemic districts since 1996-97. Compliance rate is a crucial factor in achieving elimination and was assessed in three districts of Tamil Nadu for 10th and 11th treatment rounds (TRs). An in-depth study assessed the impact of social mobilization by drug distributors (DDs) in two areas from each of the three districts. Overall coverage and compliance for assessed TRs were 76.3 and 67.7% which is below the optimum level to achieve LF elimination. Modifiable determinants continue to be the reason for non-consumption even in the 11th TR and 20.8% were systematic non-compliers. In 76.4% of the cases, DDs failed to adhere to three mandatory visits as per the guidelines. Number of visits by DDs in relation to low and high MDA coverage areas showed a significant relationship (P ≤ 0.000). MDA is limited to drug distribution alone and efforts by DDs in preparing the community were inadequate. Probable means to meet the challenges in preparation of the community is discussed.

  5. Influence of anti-filarial chemotherapy strategies on the genetic structure of Wuchereria bancrofti populations

    OpenAIRE

    Dhamodharan Ramasamy; Hoti Sugeerappa Laxmanappa; Rohit Sharma; Manoj Kumar Das

    2011-01-01

    Lymphatic filarial (LF) parasites have been under anti-filarial drug pressure for more than half a century. Currently, annual mass drug administration (MDA) of diethylcarbamazine (DEC) or ivermectin in combination with albendazole (ALB) have been used globally to eliminate LF. Long-term chemotherapies exert significant pressure on the genetic structure of parasitic populations. We investigated the genetic variation among 210 Wuchereria bancrofti populations that were under three different che...

  6. C-cinnamoyl glycosides as a new class of anti-filarial agents.

    Science.gov (United States)

    Roy, Priya; Dhara, Debashis; Parida, Pravat Kumar; Kar, Rajiv Kumar; Bhunia, Anirban; Jana, Kuladip; Sinha Babu, Santi P; Misra, Anup Kumar

    2016-05-23

    A series of C-cinnamoyl glycosides has been synthesized in good yield by the BF3·OEt2 catalyzed aldol condensation of C-glycosylated acetone derivative with a variety of aromatic aldehydes. The synthesized compounds were evaluated for their potential as anti-filarial agents against bovine filarial parasite Setaria cervi and human filariid Wuchereria bancrofti using a number of biological assays such as relative movability (RM) assessment and MTT reduction assay. Among twenty seven test compounds six compounds were found active in terms of MIC, IC50 and LC50 values. Further biological studies were carried out using three lead compounds because of their significantly low MIC values and IC50 values compared to the standard anti-filarial drug Ivermectin. In addition, structure activity relationship study of the test compounds has been carried out using 3D-QSAR analysis. PMID:27015610

  7. Influence of anti-filarial chemotherapy strategies on the genetic structure of Wuchereria bancrofti populations

    Directory of Open Access Journals (Sweden)

    Dhamodharan Ramasamy

    2011-03-01

    Full Text Available Lymphatic filarial (LF parasites have been under anti-filarial drug pressure for more than half a century. Currently, annual mass drug administration (MDA of diethylcarbamazine (DEC or ivermectin in combination with albendazole (ALB have been used globally to eliminate LF. Long-term chemotherapies exert significant pressure on the genetic structure of parasitic populations. We investigated the genetic variation among 210 Wuchereria bancrofti populations that were under three different chemotherapy strategies, namely MDA with DEC alone (group I, n = 74, MDA with DEC and ALB (group II, n = 60 and selective therapy (ST with DEC (group III, n = 34 to understand the impact of these three drug regimens on the parasite genetic structure. Randomly amplified polymorphic DNA profiles were generated for the three groups of parasite populations; the gene diversity, gene flow and genetic distance values were determined and phylogenetic trees were constructed. Analysis of these parameters indicated that parasite populations under ST with a standard dose of DEC (group III were genetically more diverse (0.2660 than parasite populations under MDA with DEC alone (group I, H = 0.2197 or with DEC + ALB (group II, H = 0.2317. These results indicate that the MDA may reduce the genetic diversity of W. bancrofti populations when compared to the genetic diversity of parasite populations under ST.

  8. Long-term follow-up of treatment with diethylcarbamazine on anti-filarial IgG4: dosage, compliance, and differential patterns in adults and children.

    Science.gov (United States)

    Terhell, A J; Haarbrink, M; van den Biggelaar, A; Mangali, A; Sartono, E; Yazdanbakhsh, M

    2003-01-01

    We have followed a population in an area endemic for Brugia malayi for three years after intensive treatment with diethylcarbamazine (DEC). Microfilariae were cleared from the circulation within four months in all eligible study participants (n = 60). There appeared to be a strong correlation between the maximum reduction in specific IgG4 and the number of days drug was taken under supervision (p = 0.41, P or = 15 years old) showed a gradual decrease in anti-filarial IgG4; 53% of these showed complete clearance of worm burden by the end of the study. In contrast, another group of male IgG4+ adults showed IgG4 patterns that started to increase between nine months and two years after treatment, indicating either a partial efficacy of DEC that allowed recovery of resident adult worms or reinfection. PMID:12556144

  9. Mining predicted essential genes of Brugia malayi for nematode drug targets.

    Science.gov (United States)

    Kumar, Sanjay; Chaudhary, Kshitiz; Foster, Jeremy M; Novelli, Jacopo F; Zhang, Yinhua; Wang, Shiliang; Spiro, David; Ghedin, Elodie; Carlow, Clotilde K S

    2007-01-01

    We report results from the first genome-wide application of a rational drug target selection methodology to a metazoan pathogen genome, the completed draft sequence of Brugia malayi, a parasitic nematode responsible for human lymphatic filariasis. More than 1.5 billion people worldwide are at risk of contracting lymphatic filariasis and onchocerciasis, a related filarial disease. Drug treatments for filariasis have not changed significantly in over 20 years, and with the risk of resistance rising, there is an urgent need for the development of new anti-filarial drug therapies. The recent publication of the draft genomic sequence for B. malayi enables a genome-wide search for new drug targets. However, there is no functional genomics data in B. malayi to guide the selection of potential drug targets. To circumvent this problem, we have utilized the free-living model nematode Caenorhabditis elegans as a surrogate for B. malayi. Sequence comparisons between the two genomes allow us to map C. elegans orthologs to B. malayi genes. Using these orthology mappings and by incorporating the extensive genomic and functional genomic data, including genome-wide RNAi screens, that already exist for C. elegans, we identify potentially essential genes in B. malayi. Further incorporation of human host genome sequence data and a custom algorithm for prioritization enables us to collect and rank nearly 600 drug target candidates. Previously identified potential drug targets cluster near the top of our prioritized list, lending credibility to our methodology. Over-represented Gene Ontology terms, predicted InterPro domains, and RNAi phenotypes of C. elegans orthologs associated with the potential target pool are identified. By virtue of the selection procedure, the potential B. malayi drug targets highlight components of key processes in nematode biology such as central metabolism, molting and regulation of gene expression.

  10. Mining predicted essential genes of Brugia malayi for nematode drug targets.

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar

    Full Text Available We report results from the first genome-wide application of a rational drug target selection methodology to a metazoan pathogen genome, the completed draft sequence of Brugia malayi, a parasitic nematode responsible for human lymphatic filariasis. More than 1.5 billion people worldwide are at risk of contracting lymphatic filariasis and onchocerciasis, a related filarial disease. Drug treatments for filariasis have not changed significantly in over 20 years, and with the risk of resistance rising, there is an urgent need for the development of new anti-filarial drug therapies. The recent publication of the draft genomic sequence for B. malayi enables a genome-wide search for new drug targets. However, there is no functional genomics data in B. malayi to guide the selection of potential drug targets. To circumvent this problem, we have utilized the free-living model nematode Caenorhabditis elegans as a surrogate for B. malayi. Sequence comparisons between the two genomes allow us to map C. elegans orthologs to B. malayi genes. Using these orthology mappings and by incorporating the extensive genomic and functional genomic data, including genome-wide RNAi screens, that already exist for C. elegans, we identify potentially essential genes in B. malayi. Further incorporation of human host genome sequence data and a custom algorithm for prioritization enables us to collect and rank nearly 600 drug target candidates. Previously identified potential drug targets cluster near the top of our prioritized list, lending credibility to our methodology. Over-represented Gene Ontology terms, predicted InterPro domains, and RNAi phenotypes of C. elegans orthologs associated with the potential target pool are identified. By virtue of the selection procedure, the potential B. malayi drug targets highlight components of key processes in nematode biology such as central metabolism, molting and regulation of gene expression.

  11. Magnetic targeted drug delivery

    Directory of Open Access Journals (Sweden)

    Timothy Wiedmann

    2009-10-01

    Full Text Available Lung cancer is the most common cause of death from cancer in both men and women. Treatment by intravenous or oral administration of chemotherapy agents results in serious and often treatment-limiting side effects. Delivery of drugs directly to the lung by inhalation of an aerosol holds the promise of achieving a higher concentration in the lung with lower blood levels. To further enhance the selective lung deposition, it may be possible to target deposition by using external magnetic fields to direct the delivery of drug coupled to magnetic particles. Moreover, alternating magnetic fields can be used to induce particle heating, which in turn controls the drug release rate with the appropriate thermal sensitive material.With this goal, superparamagetic nanoparticles (SPNP were prepared and characterized, and enhanced magnetic deposition was demonstrated in vitro and in vivo. SPNPs were also incorporated into a lipid-based/SPNP aerosol formulation, and drug release was shown to be controlled by thermal activation. Because of the inherent imaging potential of SPNPs, this use of nanotechnology offers the possibility of coupling the diagnosis of lung cancer to drug release, which perhaps will ultimately provide the “magic bullet” that Paul Ehrlich originally sought.

  12. Evaluation and validation of drug targets

    Institute of Scientific and Technical Information of China (English)

    Guan-huaDU

    2004-01-01

    Drug target is one of the key factors for discovering and developing new drugs. To find and validate drug targets is a crucial technique required in drug discovery by the strategy of high throughput screening. Based on the knowledge of molecular biology, human genomics and proteomics, it has been predicted that 5000 to 10000 drug targets exist in human. So, it is important orocedure to evaluate and validate the drug targets.

  13. Drug targeting to the brain.

    Science.gov (United States)

    Pardridge, William M

    2007-09-01

    The goal of brain drug targeting technology is the delivery of therapeutics across the blood-brain barrier (BBB), including the human BBB. This is accomplished by re-engineering pharmaceuticals to cross the BBB via specific endogenous transporters localized within the brain capillary endothelium. Certain endogenous peptides, such as insulin or transferrin, undergo receptor-mediated transport (RMT) across the BBB in vivo. In addition, peptidomimetic monoclonal antibodies (MAb) may also cross the BBB via RMT on the endogenous transporters. The MAb may be used as a molecular Trojan horse to ferry across the BBB large molecule pharmaceuticals, including recombinant proteins, antibodies, RNA interference drugs, or non-viral gene medicines. Fusion proteins of the molecular Trojan horse and either neurotrophins or single chain Fv antibodies have been genetically engineered. The fusion proteins retain bi-functional properties, and both bind the BBB receptor, to trigger transport into brain, and bind the cognate receptor inside brain to induce the pharmacologic effect. Trojan horse liposome technology enables the brain targeting of non-viral plasmid DNA. Molecular Trojan horses may be formulated with fusion protein technology, avidin-biotin technology, or Trojan horse liposomes to target to brain virtually any large molecule pharmaceutical. PMID:17554607

  14. NEW DRUG TARGETING TREATMENT - GLIVEC

    Institute of Scientific and Technical Information of China (English)

    SUN Xue-mei(孙雪梅); BRADY Ben

    2003-01-01

    This review evaluates the role of Glivec in the treatment of chronic myelogenous leukemia and other malignant tumors. Preclinical and clinical evidence showed that Glivec demonstrated a potent and specific inhibition on BCR-ABL positive leukemias and other malignant tumors in which overexpression of c-kit and PDGFR-β played a major role in their pathogenesis. Glivec has induced complete hematologic responses in up to 98% of patients evaluated in clinical trials. It's a very successful drug that supported the idea of targeted therapy through inhibition of tyrosine kinases. Although it's still in the early stages of clinical development and the resistance to Glivec remains to be a problem needed further study, a great deal has been learned from these research and observation. And with the increasing data, molecular targeting therapy will play much more important role in the treatment of malignant tumors. With the better understanding of the pathogenesis of malignant tumors, well-designed drugs targeting the specific molecular abnormalities with higher efficacy and lower side effect will benefit numerous patients with malignant tumors.

  15. Drug targeting through pilosebaceous route.

    Science.gov (United States)

    Chourasia, Rashmi; Jain, Sanjay K

    2009-10-01

    Local skin targeting is of interest for the pharmaceutical and the cosmetic industry. A topically applied substance has basically three possibilities to penetrate into the skin: transcellular, intercellular, and follicular. The transfollicular path has been largely ignored because hair follicles constitute only 0.1% of the total skin. The hair follicle is a skin appendage with a complex structure containing many cell types that produce highly specialised proteins. The hair follicle is in a continuous cycle: anagen is the hair growth phase, catagen the involution phase and telogen is the resting phase. Nonetheless, the hair follicle has great potential for skin treatment, owing to its deep extension into the dermis and thus provides much deeper penetration and absorption of compounds beneath the skin than seen with the transdermal route. In the case of skin diseases and of cosmetic products, delivery to sweat glands or to the pilosebaceous unit is essential for the effectiveness of the drug. Increased accumulation in the pilosebaceous unit could treat alopecia, acne and skin cancer more efficiently and improve the effect of cosmetic substances and nutrients. Therefore, we review herein various drug delivery systems, including liposomes, niosomes, microspheres, nanoparticles, nanoemulsions, lipid nanocarriers, gene therapy and discuss the results of recent researches. We also review the drugs which have been investigated for pilosebaceous delivery.

  16. Drug targeting through pilosebaceous route.

    Science.gov (United States)

    Chourasia, Rashmi; Jain, Sanjay K

    2009-10-01

    Local skin targeting is of interest for the pharmaceutical and the cosmetic industry. A topically applied substance has basically three possibilities to penetrate into the skin: transcellular, intercellular, and follicular. The transfollicular path has been largely ignored because hair follicles constitute only 0.1% of the total skin. The hair follicle is a skin appendage with a complex structure containing many cell types that produce highly specialised proteins. The hair follicle is in a continuous cycle: anagen is the hair growth phase, catagen the involution phase and telogen is the resting phase. Nonetheless, the hair follicle has great potential for skin treatment, owing to its deep extension into the dermis and thus provides much deeper penetration and absorption of compounds beneath the skin than seen with the transdermal route. In the case of skin diseases and of cosmetic products, delivery to sweat glands or to the pilosebaceous unit is essential for the effectiveness of the drug. Increased accumulation in the pilosebaceous unit could treat alopecia, acne and skin cancer more efficiently and improve the effect of cosmetic substances and nutrients. Therefore, we review herein various drug delivery systems, including liposomes, niosomes, microspheres, nanoparticles, nanoemulsions, lipid nanocarriers, gene therapy and discuss the results of recent researches. We also review the drugs which have been investigated for pilosebaceous delivery. PMID:19663765

  17. Antiepileptic drugs: newer targets and new drugs

    OpenAIRE

    Vihang S. Chawan; Abhishek M. Phatak; Kalpesh V. Gawand; Sagar V. Badwane; Sagar S. Panchal

    2016-01-01

    Epilepsy is a common neurological disorder affecting 0.5-1% of the population in India. Majority of patients respond to currently available antiepileptic drugs (AEDs), but a small percentage of patients have shown poor and inadequate response to AEDs in addition to various side effects and drug interactions while on therapy. Thus there is a need to develop more effective AEDs in drug resistant epilepsy which have a better safety profile with minimal adverse effects. The United States food and...

  18. Aquaporins as potential drug targets

    Institute of Scientific and Technical Information of China (English)

    Fang WANG; Xue-chao FENG; Yong-ming LI; Hong YANG; Tong-hui MA

    2006-01-01

    The aquaporins (AQP) are a family of integral membrane proteins that selectively transport water and,in some cases,small neutral solutes such as glycerol and urea.Thirteen mammalian AQP have been molecularly identified and localized to various epithelial,endothelial and other tissues.Phenotype studies of transgenic mouse models of AQP knockout,mutation,and in some cases humans with AQP mutations have demonstrated essential roles for AQP in mammalian physiology and pathophysiology,including urinary concentrating function,exocrine glandular fluid secretion,brain edema formation,regulation of intracranial and intraocular pressure,skin hydration,fat metabolism,tumor angiogenesis and cell migration.These studies suggest that AQP may be potential drug targets for not only new diuretic reagents for various forms of pathological water retention,but also targets for novel therapy of brain edema,inflammatory disease,glaucoma,obesity,and cancer.However,potent AQP modulators for in vivo application remain to be discovered.

  19. Antiepileptic drugs: newer targets and new drugs

    Directory of Open Access Journals (Sweden)

    Vihang S. Chawan

    2016-06-01

    Full Text Available Epilepsy is a common neurological disorder affecting 0.5-1% of the population in India. Majority of patients respond to currently available antiepileptic drugs (AEDs, but a small percentage of patients have shown poor and inadequate response to AEDs in addition to various side effects and drug interactions while on therapy. Thus there is a need to develop more effective AEDs in drug resistant epilepsy which have a better safety profile with minimal adverse effects. The United States food and drug administration (USFDA has approved eslicarbazepine acetate, ezogabine, perampanel and brivaracetam which have shown a promising future as better AEDs and drugs like ganaxolone, intranasal diazepam, ICA- 105665, valnoctamide, VX-765, naluzotan are in the pipeline. [Int J Basic Clin Pharmacol 2016; 5(3.000: 587-592

  20. Nanogel Carrier Design for Targeted Drug Delivery

    OpenAIRE

    Eckmann, D.M.; Composto, R. J.; Tsourkas, A; Muzykantov, V. R.

    2014-01-01

    Polymer-based nanogel formulations offer features attractive for drug delivery, including ease of synthesis, controllable swelling and viscoelasticity as well as drug loading and release characteristics, passive and active targeting, and the ability to formulate nanogel carriers that can respond to biological stimuli. These unique features and low toxicity make the nanogels a favorable option for vascular drug targeting. In this review, we address key chemical and biological aspects of nanoge...

  1. Targeted Drug Delivery in Pancreatic Cancer

    Science.gov (United States)

    Yu, Xianjun; Zhang, Yuqing; Chen, Changyi; Yao, Qizhi; Li, Min

    2009-01-01

    Effective drug delivery in pancreatic cancer treatment remains a major challenge. Because of the high resistance to chemo and radiation therapy, the overall survival rate for pancreatic cancer is extremely low. Recent advances in drug delivery systems hold great promise for improving cancer therapy. Using liposomes, nanoparticles, and carbon nanotubes to deliver cancer drugs and other therapeutic agents such as siRNA, suicide gene, oncolytic virus, small molecule inhibitor and antibody has been a success in recent pre-clinical trials. However, how to improve the specificity and stability of the delivered drug using ligand or antibody directed delivery represent a major problem. Therefore, developing novel, specific, tumor-targeted drug delivery systems is urgently needed for this terrible disease. This review summarizes the current progress on targeted drug delivery in pancreatic cancer, and provides important information on potential therapeutic targets for pancreatic cancer treatment. PMID:19853645

  2. Splicing regulators: targets and drugs

    OpenAIRE

    Yeo, Gene Wei-Ming

    2005-01-01

    Silencing of splicing regulators by RNA interference, combined with splicing-specific microarrays, has revealed a complex network of distinct alternative splicing events in Drosophila, while a high-throughput screen of more than 6,000 compounds has identified drugs that interfere specifically and directly with one class of splicing regulators in human cells.

  3. Drug targeting using solid lipid nanoparticles.

    Science.gov (United States)

    Rostami, Elham; Kashanian, Soheila; Azandaryani, Abbas H; Faramarzi, Hossain; Dolatabadi, Jafar Ezzati Nazhad; Omidfar, Kobra

    2014-07-01

    The present review aims to show the features of solid lipid nanoparticles (SLNs) which are at the forefront of the rapidly developing field of nanotechnology with several potential applications in drug delivery and research. Because of some unique features of SLNs such as their unique size dependent properties it offers possibility to develop new therapeutics. A common denominator of all these SLN-based platforms is to deliver drugs into specific tissues or cells in a pathological setting with minimal adverse effects on bystander cells. SLNs are capable to incorporate drugs into nanocarriers which lead to a new prototype in drug delivery which maybe used for drug targeting. Hence solid lipid nanoparticles hold great promise for reaching the goal of controlled and site specific drug delivery and hence attracted wide attention of researchers. This review presents a broad treatment of targeted solid lipid nanoparticles discussing their types such as antibody SLN, magnetic SLN, pH sensitive SLN and cationic SLN. PMID:24717692

  4. Aptamers for Targeted Drug Delivery

    Directory of Open Access Journals (Sweden)

    Partha Ray

    2010-05-01

    Full Text Available Aptamers are a class of therapeutic oligonucleotides that form specific three-dimensional structures that are dictated by their sequences. They are typically generated by an iterative screening process of complex nucleic acid libraries employing a process termed Systemic Evolution of Ligands by Exponential Enrichment (SELEX. SELEX has traditionally been performed using purified proteins, and cell surface receptors may be challenging to purify in their properly folded and modified conformations. Therefore, relatively few aptamers have been generated that bind cell surface receptors. However, improvements in recombinant fusion protein technology have increased the availability of receptor extracellular domains as purified protein targets, and the development of cell-based selection techniques has allowed selection against surface proteins in their native configuration on the cell surface. With cell-based selection, a specific protein target is not always chosen, but selection is performed against a target cell type with the goal of letting the aptamer choose the target. Several studies have demonstrated that aptamers that bind cell surface receptors may have functions other than just blocking receptor-ligand interactions. All cell surface proteins cycle intracellularly to some extent, and many surface receptors are actively internalized in response to ligand binding. Therefore, aptamers that bind cell surface receptors have been exploited for the delivery of a variety of cargoes into cells. This review focuses on recent progress and current challenges in the field of aptamer-mediated delivery.

  5. LIVER SPECIFIC DRUG TARGETING STRATEGIES: A REVIEW

    OpenAIRE

    Ramesh S. Gorad*, Satish K. Mandlik and Kishore N. Gujar

    2013-01-01

    Drug delivery to liver is one of the most challenging research areas in pharmaceutical sciences. The some physiological barrier such as opsonization, mechanical entrapment by pulmonary vascular bed, uptake by RES represents an insurmountable obstacle for a large number of proteins and drugs, including antibiotics, antineoplastic agents and antiviral agents to target liver disorders. Therefore, various strategies have been proposed to improve the delivery of different drugs to liver and hepato...

  6. Mathematical modelling of magnetically targeted drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Grief, Andrew D. [Theoretical Mechanics, School of Mathematical Sciences, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)]. E-mail: andrew.grief@nottingham.ac.uk; Richardson, Giles [Theoretical Mechanics, School of Mathematical Sciences, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)]. E-mail: giles.richardson@nottingham.ac.uk

    2005-05-15

    A mathematical model for targeted drug delivery using magnetic particles is developed. This includes a diffusive flux of particles arising from interactions between erythrocytes in the microcirculation. The model is used to track particles in a vessel network. Magnetic field design is discussed and we show that it is impossible to specifically target internal regions using an externally applied field.

  7. Targeted Delivery of Protein Drugs by Nanocarriers

    Directory of Open Access Journals (Sweden)

    Antonella Battisti

    2010-03-01

    Full Text Available Recent advances in biotechnology demonstrate that peptides and proteins are the basis of a new generation of drugs. However, the transportation of protein drugs in the body is limited by their high molecular weight, which prevents the crossing of tissue barriers, and by their short lifetime due to immuno response and enzymatic degradation. Moreover, the ability to selectively deliver drugs to target organs, tissues or cells is a major challenge in the treatment of several human diseases, including cancer. Indeed, targeted delivery can be much more efficient than systemic application, while improving bioavailability and limiting undesirable side effects. This review describes how the use of targeted nanocarriers such as nanoparticles and liposomes can improve the pharmacokinetic properties of protein drugs, thus increasing their safety and maximizing the therapeutic effect.

  8. Fluid mechanics aspects of magnetic drug targeting.

    Science.gov (United States)

    Odenbach, Stefan

    2015-10-01

    Experiments and numerical simulations using a flow phantom for magnetic drug targeting have been undertaken. The flow phantom is a half y-branched tube configuration where the main tube represents an artery from which a tumour-supplying artery, which is simulated by the side branch of the flow phantom, branches off. In the experiments a quantification of the amount of magnetic particles targeted towards the branch by a magnetic field applied via a permanent magnet is achieved by impedance measurement using sensor coils. Measuring the targeting efficiency, i.e. the relative amount of particles targeted to the side branch, for different field configurations one obtains targeting maps which combine the targeting efficiency with the magnetic force densities in characteristic points in the flow phantom. It could be shown that targeting efficiency depends strongly on the magnetic field configuration. A corresponding numerical model has been set up, which allows the simulation of targeting efficiency for variable field configuration. With this simulation good agreement of targeting efficiency with experimental data has been found. Thus, the basis has been laid for future calculations of optimal field configurations in clinical applications of magnetic drug targeting. Moreover, the numerical model allows the variation of additional parameters of the drug targeting process and thus an estimation of the influence, e.g. of the fluid properties on the targeting efficiency. Corresponding calculations have shown that the non-Newtonian behaviour of the fluid will significantly influence the targeting process, an aspect which has to be taken into account, especially recalling the fact that the viscosity of magnetic suspensions depends strongly on the magnetic field strength and the mechanical load. PMID:26415215

  9. LIVER SPECIFIC DRUG TARGETING STRATEGIES: A REVIEW

    Directory of Open Access Journals (Sweden)

    Ramesh S. Gorad*, Satish K. Mandlik and Kishore N. Gujar

    2013-11-01

    Full Text Available Drug delivery to liver is one of the most challenging research areas in pharmaceutical sciences. The some physiological barrier such as opsonization, mechanical entrapment by pulmonary vascular bed, uptake by RES represents an insurmountable obstacle for a large number of proteins and drugs, including antibiotics, antineoplastic agents and antiviral agents to target liver disorders. Therefore, various strategies have been proposed to improve the delivery of different drugs to liver and hepatocytes which includes passive accumulation of nanoparticle therapeutics and active targeting by surface modifications of nanoparticles with specific ligands such as carbohydrates, peptides, proteins and antibodies. The present review enlightens about different pathologies of liver and targeting strategies employed in relation to liver anatomy and disease etiologies.

  10. P-glycoprotein targeted nanoscale drug carriers

    KAUST Repository

    Li, Wengang

    2013-02-01

    Multi-drug resistance (MDR) is a trend whereby tumor cells exposed to one cytotoxic agent develop cross-resistance to a range of structurally and functionally unrelated compounds. P -glycoprotein (P -gp) efflux pump is one of the mostly studied drug carrying processes that shuttle the drugs out of tumor cells. Thus, P -gp inhibitors have attracted a lot of attention as they can stop cancer drugs from being pumped out of target cells with the consumption of ATP. Using quantitive structure activity relationship (QSAR), we have successfully synthesized a series of novel P -gp inhibitors. The obtained dihydropyrroloquinoxalines series were fully characterized and then tested against bacterial and tumor assays with over-expressed P -gps. All compounds were bioactive especially compound 1c that had enhanced antibacterial activity. Furthermore, these compounds were utilized as targeting vectors to direct drug delivery vehicles such as silica nanoparticles (SNPs) to cancerous Hela cells with over expressed P -gps. Cell uptake studies showed a successful accumulation of these decorated SNPs in tumor cells compared to undecorated SNPs. The results obtained show that dihydropyrroloquinoxalines constitute a promising drug candidate for targeting cancers with MDR. Copyright © 2013 American Scientific Publishers All rights reserved.

  11. Targeting molecular networks for drug research

    Directory of Open Access Journals (Sweden)

    José Pedro Pinto

    2014-06-01

    Full Text Available The study of molecular networks has recently moved into the limelight of biomedical research. While it has certainly provided us with plenty of new insights into cellular mechanisms, the challenge now is how to modify or even restructure these networks. This is especially true for human diseases, which can be regarded as manifestations of distorted states of molecular networks. Of the possible interventions for altering networks, the use of drugs is presently the most feasible. In this mini-review, we present and discuss some exemplary approaches of how analysis of molecular interaction networks can contribute to pharmacology (e.g., by identifying new drug targets or prediction of drug side effects, as well as listing pointers to relevant resources and software to guide future research. We also outline recent progress in the use of drugs for in vitro reprogramming of cells, which constitutes an example par excellence for altering molecular interaction networks with drugs.

  12. Mystery unraveled about antifungal drug targets

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ A long-standing mystery about the functional roles of the N-terminal region of protein N-myristoyltransferase, an ideal target for antifungal drugs, was recently decoded, thanks to the threeyear joint efforts of researchers from the CAS Key Laboratory of Molecular Biology and their US colleagues at the DuPont Stine Haskell Research Center.

  13. Drug-induced regulation of target expression

    DEFF Research Database (Denmark)

    Iskar, Murat; Campillos, Monica; Kuhn, Michael;

    2010-01-01

    further newly identified drug-induced differential regulation of Lanosterol 14-alpha demethylase, Endoplasmin, DNA topoisomerase 2-alpha and Calmodulin 1. The feedback regulation in these and other targets is likely to be relevant for the success or failure of the molecular intervention....

  14. Extracellular proteases as targets for drug development.

    Science.gov (United States)

    Cudic, Mare; Fields, Gregg B

    2009-08-01

    Proteases constitute one of the primary targets in drug discovery. In the present review, we focus on extracellular proteases (ECPs) because of their differential expression in many pathophysiological processes, including cancer, cardiovascular conditions, and inflammatory, pulmonary, and periodontal diseases. Many new ECP inhibitors are currently under clinical investigation and a significant increase in new therapies based on protease inhibition can be expected in the coming years. In addition to directly blocking the activity of a targeted protease, one can take advantage of differential expression in disease states to selectively deliver therapeutic or imaging agents. Recent studies in targeted drug development for the metalloproteases (matrix metalloproteinases, adamalysins, pappalysins, neprilysin, angiotensin-converting enzyme, metallocarboxypeptidases, and glutamate carboxypeptidase II), serine proteases (elastase, coagulation factors, tissue/urokinase plasminogen activator system, kallikreins, tryptase, dipeptidyl peptidase IV) and cysteine proteases (cathepsin B) are discussed herein. PMID:19689354

  15. Possible implication of oxidative stress in anti filarial effect of certain traditionally used medicinal plants in vitro against Brugia malayi microfilariae

    Directory of Open Access Journals (Sweden)

    R D Sharma

    2010-01-01

    Full Text Available Introduction: Tropical disease research scheme of World Health Organization has duly recognized traditional medicine as alternative for antifilarial drug development. Polyphenolic compounds present in traditionally used herbal medicines are natural antioxidants; however, paradoxically they may exert pro-oxidant effect. Popular drug diethyl carbamazine citrate harnesses the innate inflammatory response and the consequent oxidative assault to combat invading microbes. Methods: With this perspective, extracts of Vitex negundo L. (roots, Butea monosperma L. (leaves, Aegle marmelos Corr. (leaves, and Ricinus communis L. (leaves were selected to explore the possible role of oxidative rationale in the antifilarial effect in vitro. Results: Apart from the last, other three plant extracts were reported to have polyphenolic compounds. Dose-dependent increase was found in the levels of lipid peroxidation and protein carbonylation for all the three plant extracts except Ricinus communis L. (leaves. Such increase in oxidative parameters also showed some degree of plant-specific predilection in terms of relatively higher level of particular oxidative parameter. High degree of correlation was observed between the antifilarial effect and the levels of corresponding oxidative stress parameters for these three plants. However, extracts of Ricinus communis L. (leaves which is relatively deficient in polyphenolic ingredients recorded maximum 30% loss of motility and also did not show any significant difference in various stress parameters from corresponding control levels. Conclusion: These results reveal that targeted oxidative stress might be crucial in the pharmacodynamics.

  16. Targeted proteins for diabetes drug design

    Science.gov (United States)

    Doan Trang Nguyen, Ngoc; Thi Le, Ly

    2012-03-01

    Type 2 diabetes mellitus is a common metabolism disorder characterized by high glucose in the bloodstream, especially in the case of insulin resistance and relative insulin deficiency. Nowadays, it is very common in middle-aged people and involves such dangerous symptoms as increasing risk of stroke, obesity and heart failure. In Vietnam, besides the common treatment of insulin injection, some herbal medication is used but no unified optimum remedy for the disease yet exists and there is no production of antidiabetic drugs in the domestic market yet. In the development of nanomedicine at the present time, drug design is considered as an innovative tool for researchers to study the mechanisms of diseases at the molecular level. The aim of this article is to review some common protein targets involved in type 2 diabetes, offering a new idea for designing new drug candidates to produce antidiabetic drugs against type 2 diabetes for Vietnamese people.

  17. Strategies to improve intracellular drug delivery by targeted liposomes

    NARCIS (Netherlands)

    Fretz, M.M.

    2007-01-01

    Biotechnological advances increased the number of novel macromolecular drugs and new drug targets. The latter are mostly found intracellular. Unfortunately, most of the new macromolecular drugs rely on drug delivery tools for their intracellular delivery because their unfavourable physicochemical pr

  18. Tumor targeting using liposomal antineoplastic drugs

    Directory of Open Access Journals (Sweden)

    Jörg Huwyler

    2008-03-01

    Full Text Available Jörg Huwyler1, Jürgen Drewe2, Stephan Krähenbühl21University of Applied Sciences Northwestern Switzerland, Institute of Pharma Technology, Muttenz, Switzerland; 2Department of Research and Division of Clinical Pharmacology, University Hospital Basel, Basel, SwitzerlandAbstract: During the last years, liposomes (microparticulate phospholipid vesicles have beenused with growing success as pharmaceutical carriers for antineoplastic drugs. Fields of application include lipid-based formulations to enhance the solubility of poorly soluble antitumordrugs, the use of pegylated liposomes for passive targeting of solid tumors as well as vector-conjugated liposomal carriers for active targeting of tumor tissue. Such formulation and drug targeting strategies enhance the effectiveness of anticancer chemotherapy and reduce at the same time the risk of toxic side-effects. The present article reviews the principles of different liposomal technologies and discusses current trends in this field of research.Keywords: tumor targeting, antineoplastic drugs, liposomes, pegylation, steric stabilization, immunoliposomes

  19. Mining metabolic networks for optimal drug targets.

    Science.gov (United States)

    Sridhar, Padmavati; Song, Bin; Kahveci, Tamer; Ranka, Sanjay

    2008-01-01

    Recent advances in bioinformatics promote drug-design methods that aim to reduce side-effects. Efficient computational methods are required to identify the optimal enzyme-combination (i.e., drug targets) whose inhibition, will achieve the required effect of eliminating a given target set of compounds, while incurring minimal side-effects. We formulate the optimal enzyme-combination identification problem as an optimization problem on metabolic networks. We define a graph based computational damage model that encapsulates the impact of enzymes onto compounds in metabolic networks. We develop a branch-and-bound algorithm, named OPMET, to explore the search space dynamically. We also develop two filtering strategies to prune the search space while still guaranteeing an optimal solution. They compute an upper bound to the number of target compounds eliminated and a lower bound to the side-effect respectively. Our experiments on the human metabolic network demonstrate that the proposed algorithm can accurately identify the target enzymes for known successful drugs in the literature. Our experiments also show that OPMET can reduce the total search time by several orders of magnitude as compared to the exhaustive search. PMID:18229694

  20. Chemical signatures and new drug targets for gametocytocidal drug development

    Science.gov (United States)

    Sun, Wei; Tanaka, Takeshi Q.; Magle, Crystal T.; Huang, Wenwei; Southall, Noel; Huang, Ruili; Dehdashti, Seameen J.; McKew, John C.; Williamson, Kim C.; Zheng, Wei

    2014-01-01

    Control of parasite transmission is critical for the eradication of malaria. However, most antimalarial drugs are not active against P. falciparum gametocytes, responsible for the spread of malaria. Consequently, patients can remain infectious for weeks after the clearance of asexual parasites and clinical symptoms. Here we report the identification of 27 potent gametocytocidal compounds (IC50 oocyst formation in a mouse model of transmission. These results provide critical new leads and potential targets to expand the repertoire of malaria transmission-blocking reagents.

  1. Targeting of antileishmanial drugs produced by nanotechnologies

    OpenAIRE

    Pujals Naranjo, Georgina

    2007-01-01

    The aim of this work is to develop an effective new MGA delivery system by means of nanotechnology for the treatment of leishmaniosis which could be administered by parenteral or oral route in a future. Moreover, for ensuring the effectiveness of the formulations developed, their in vitro activities will be assessed against L. infantum. The intention is to prepare a target drug delivery system by means of different technological strategies like micro-nanoparticles by spray drying. These formu...

  2. Extracellular proteases as targets for drug development

    OpenAIRE

    Cudic, Mare; Fields, Gregg B.

    2009-01-01

    Proteases constitute one of the primary targets in drug discovery. In the present review, we focus on extracellular proteases (ECPs) because of their differential expression in many pathophysiological processes, including cancer, cardiovascular conditions, and inflammatory, pulmonary, and periodontal diseases. Many new ECP inhibitors are currently under clinical investigation and a significant increase in new therapies based on protease inhibition can be expected in the coming years. In addit...

  3. Reduction in acute filariasis morbidity during a mass drug administration trial to eliminate lymphatic filariasis in Papua New Guinea.

    OpenAIRE

    Tisch, Daniel J; Alexander, Neal D. E.; Benson Kiniboro; Henry Dagoro; Siba, Peter M.; Bockarie, Moses J.; Alpers, Michael P.; Kazura, James W.

    2011-01-01

    BACKGROUND: Acute painful swelling of the extremities and scrotum are debilitating clinical manifestations of Wuchereria bancrofti infection. The ongoing global program to eliminate filariasis using mass drug administration is expected to decrease this and other forms of filarial morbidity in the future by preventing establishment of new infections as a consequence of eliminating transmission by the mosquito vector. We examined whether mass treatment with anti-filarial drugs has a more immedi...

  4. Reduction in Acute Filariasis Morbidity during a Mass Drug Administration Trial to Eliminate Lymphatic Filariasis in Papua New Guinea

    OpenAIRE

    Tisch, DJ; Alexander, NDE; Kiniboro, B.; Dagoro, H; Siba, PM; Bockarie, MJ; Alpers, MP; Kazura, JW

    2011-01-01

    Background: Acute painful swelling of the extremities and scrotum are debilitating clinical manifestations of Wuchereria bancrofti infection. The ongoing global program to eliminate filariasis using mass drug administration is expected to decrease this and other forms of filarial morbidity in the future by preventing establishment of new infections as a consequence of eliminating transmission by the mosquito vector. We examined whether mass treatment with anti-filarial drugs has a more immedi...

  5. Prediction of potential drug targets based on simple sequence properties

    Directory of Open Access Journals (Sweden)

    Lai Luhua

    2007-09-01

    Full Text Available Abstract Background During the past decades, research and development in drug discovery have attracted much attention and efforts. However, only 324 drug targets are known for clinical drugs up to now. Identifying potential drug targets is the first step in the process of modern drug discovery for developing novel therapeutic agents. Therefore, the identification and validation of new and effective drug targets are of great value for drug discovery in both academia and pharmaceutical industry. If a protein can be predicted in advance for its potential application as a drug target, the drug discovery process targeting this protein will be greatly speeded up. In the current study, based on the properties of known drug targets, we have developed a sequence-based drug target prediction method for fast identification of novel drug targets. Results Based on simple physicochemical properties extracted from protein sequences of known drug targets, several support vector machine models have been constructed in this study. The best model can distinguish currently known drug targets from non drug targets at an accuracy of 84%. Using this model, potential protein drug targets of human origin from Swiss-Prot were predicted, some of which have already attracted much attention as potential drug targets in pharmaceutical research. Conclusion We have developed a drug target prediction method based solely on protein sequence information without the knowledge of family/domain annotation, or the protein 3D structure. This method can be applied in novel drug target identification and validation, as well as genome scale drug target predictions.

  6. VNP: Interactive Visual Network Pharmacology of Diseases, Targets, and Drugs

    OpenAIRE

    Hu, Q-N; Deng, Z.; Tu, W; X. Yang; Meng, Z-B; Deng, Z-X; Liu, J

    2014-01-01

    In drug discovery, promiscuous targets, multifactorial diseases, and “dirty” drugs construct complex network relationships. Network pharmacology description and analysis not only give a systems-level understanding of drug action and disease complexity but can also help to improve the efficiency of target selection and drug design. Visual network pharmacology (VNP) is developed to visualize network pharmacology of targets, diseases, and drugs with a graph network by using disease, target or dr...

  7. Anti-Wolbachia drug discovery and development: safe macrofilaricides for onchocerciasis and lymphatic filariasis

    OpenAIRE

    Taylor, Mark J; Hoerauf, Achim; TOWNSON, SIMON; Slatko, Barton E; Ward, Stephen A.

    2013-01-01

    SUMMARY Anti-Wolbachia therapy delivers safe macrofilaricidal activity with superior therapeutic outcomes compared to all standard anti-filarial treatments, with the added benefit of substantial improvements in clinical pathology. These outcomes can be achieved, in principle, with existing registered drugs, e.g. doxycycline, that are affordable, available to endemic communities and have well known, albeit population-limiting, safety profiles. The key barriers to using doxycycline as an mass d...

  8. Bioinspired Nanonetworks for Targeted Cancer Drug Delivery.

    Science.gov (United States)

    Raz, Nasibeh Rady; Akbarzadeh-T, Mohammad-R; Tafaghodi, Mohsen

    2015-12-01

    A biomimicry approach to nanonetworks is proposed here for targeted cancer drug delivery (TDD). The swarm of bioinspired nanomachines utilizes the blood distribution network and chemotaxis to carry drug through the vascular system to the cancer site, recognized by a high concentration of vascular endothelial growth factor (VEGF). Our approach is multi-scale and includes processes that occur both within cells and with their neighbors. The proposed bionanonetwork takes advantage of several organic processes, some of which already occur within the human body, such as a plate-like structure similar to those of red blood cells for more environmental contact; a berry fruit architecture for its internal multi-foams architecture; the penetrable structure of cancer cells, tissue, as well as the porous structure of the capillaries for drug penetration; state of glycocalyx for ligand-receptor adhesion; as well as changes in pH state of blood and O 2 release for nanomachine communication. For a more appropriate evaluation, we compare our work with a conventional chemotherapy approach using a mathematical model of cancer under actual experimental parameter settings. Simulation results show the merits of the proposed method in targeted cancer therapy by improving the densities of the relevant cancer cell types and VEGF concentration, while following more organic and natural processes. PMID:26529771

  9. Drug-therapy networks and the predictions of novel drug targets

    OpenAIRE

    Spiro, Zoltan; Kovacs, Istvan A.; Csermely, Peter

    2008-01-01

    Recently, a number of drug-therapy, disease, drug, and drug-target networks have been introduced. Here we suggest novel methods for network-based prediction of novel drug targets and for improvement of drug efficiency by analysing the effects of drugs on the robustness of cellular networks.

  10. Cooperative assembly in targeted drug delivery

    Science.gov (United States)

    Auguste, Debra

    2012-02-01

    Described as cell analogues, liposomes are self-assembled lipid bilayer spheres that encapsulate aqueous volumes. Liposomes offer several drug delivery advantages due to their structural versatility related to size, composition, bilayer fluidity, and ability to encapsulate a large variety of compounds non-covalently. However, liposomes lack the structural information embedded within cell membranes. Partitioning of unsaturated and saturated lipids into liquid crystalline (Lα) and gel phase (Lβ) domains, respectively, affects local molecular diffusion and elasticity. Liposome microdomains may be used to pattern molecules, such as antibodies, on the liposome surface to create concentrated, segregated binding regions. We have synthesized, characterized, and evaluated a series of homogeneous and heterogeneous liposomal vehicles that target inflamed endothelium. These drug delivery vehicles are designed to complement the heterogeneous presentation of lipids and receptors on endothelial cells (ECs). EC surfaces are dynamic; they segregate receptors within saturated lipid microdomains on the cell surface to regulate binding and signaling events. We have demonstrated that cooperative binding of two antibodies enhances targeting by multiple fold. Further, we have shown that organization of these antibodies on the surface can further enhance cell uptake. The data suggest that EC targeting may be enhanced by designing liposomes that mirror the segregated structure of lipid and receptor molecules involved in neutrophil-EC adhesion. This strategy is employed in an atherosclerotic mouse model in vivo.

  11. Emerging migraine treatments and drug targets

    DEFF Research Database (Denmark)

    Olesen, Jes; Ashina, Messoud

    2011-01-01

    Migraine has a 1-year prevalence of 10% and high socioeconomic costs. Despite recent drug developments, there is a huge unmet need for better pharmacotherapy. In this review we discuss promising anti-migraine strategies such as calcitonin gene-related peptide (CGRP) receptor antagonists and 5......-hydroxytrypamine (5-HT)(1F) receptor agonists, which are in late-stage development. Nitric oxide antagonists are also in development. New forms of administration of sumatriptan might improve efficacy and reduce side effects. Botulinum toxin A has recently been approved for the prophylaxis of chronic migraine....... Tonabersat, a cortical spreading depression inhibitor, has shown efficacy in the prophylaxis of migraine with aura. Several new drug targets such as nitric oxide synthase, the 5-HT(1D) receptor, the prostanoid receptors EP(2) and EP(4), and the pituitary adenylate cyclase receptor PAC1 await development. The...

  12. New drugs and treatment targets in psoriasis.

    Science.gov (United States)

    Kofoed, Kristian; Skov, Lone; Zachariae, Claus

    2015-02-01

    In recent years, the increased understanding of the pathophysiology of psoriasis has resulted in several new treatments. The success of ustekinumab proved the importance of the IL-23/T helper cell 17 axis in psoriatic diseases. Several new biologics targeting this axis will reach the clinic in the next years. Biologics are costly, require injections, and some patients experience tacaphylaxis, thus, the development of orally available, small-molecule inhibitors is desirable. Among small-molecules under investigation are A3 adenosine receptor agonists, Janus kinase inhibitors, and phosphodiesterase inhibitors. We review published clinical trials, and conference abstracts presented during the last years, concerned with new drugs under development for the treatment of psoriasis. In conclusion, our psoriasis armamentarium will be filled with several new effective therapeutic options the coming years. We need to be aware of the limitations of drug safety data when selecting new novel treatments. Monitoring and clinical registries are still important tools.

  13. New Drugs and Treatment Targets in Psoriasis

    DEFF Research Database (Denmark)

    Kofoed, Kristian; Skov, Lone; Zachariae, Claus

    2015-01-01

    In recent years, the increased understanding of the pathophysiology of psoriasis has resulted in several new treatments. The success of ustekinumab proved the importance of the IL-23/T helper cell 17 axis in psoriatic diseases. Several new biologics targeting this axis will reach the clinic......, and phosphodiesterase inhibitors. We review published clinical trials, and conference abstracts presented during the last years, concerned with new drugs under development for the treatment of psoriasis. In conclusion, our psoriasis armamentarium will be filled with several new effective therapeutic options the coming...... years. We need to be aware of the limitations of drug safety data when selecting new novel treatments. Monitoring and clinical registries are still important tools....

  14. Emerging migraine treatments and drug targets

    DEFF Research Database (Denmark)

    Olesen, Jes; Ashina, Messoud

    2011-01-01

    Migraine has a 1-year prevalence of 10% and high socioeconomic costs. Despite recent drug developments, there is a huge unmet need for better pharmacotherapy. In this review we discuss promising anti-migraine strategies such as calcitonin gene-related peptide (CGRP) receptor antagonists and 5......-hydroxytrypamine (5-HT)(1F) receptor agonists, which are in late-stage development. Nitric oxide antagonists are also in development. New forms of administration of sumatriptan might improve efficacy and reduce side effects. Botulinum toxin A has recently been approved for the prophylaxis of chronic migraine....... Tonabersat, a cortical spreading depression inhibitor, has shown efficacy in the prophylaxis of migraine with aura. Several new drug targets such as nitric oxide synthase, the 5-HT(1D) receptor, the prostanoid receptors EP(2) and EP(4), and the pituitary adenylate cyclase receptor PAC1 await development...

  15. Meningococcal disease and future drug targets

    DEFF Research Database (Denmark)

    Colding, Hanne; Hartzen, S H; Penkowa, Milena;

    2011-01-01

    recent data and current knowledge on molecular mechanisms of meningococcal disease and explains how host immune responses ultimately may aggravate neuropathology and the clinical prognosis. Within this context, particular importance is paid to the endotoxic components that provide potential drug targets......Neisseria meningitidis (N. meningitidis) causes sepsis, epidemic meningitis, and sometimes also meningoencephalitis. Despite early antibiotic treatment, mortality and morbidity remain significant. We present recent studies on meningococcal disease with focus on the pathophysiology caused......-host interactions are key determinants of the clinical course and risk of fatal outcome. Accordingly, successful treatment of severe meningococcal disease requires not only antibiotics but also adjuvants targeting the released endotoxins and the host immune/inflammatory responses. This review highlights the most...

  16. The hydrogenosome as a drug target.

    Science.gov (United States)

    Benchimol, Marlene

    2008-01-01

    Hydrogenosomes are spherical or slightly elongated organelles found in non-mitochondrial organisms. In Trichomonas hydrogenosomes measure between 200 to 500 nm, but under drug treatment they can reach 2 microm. Like mitochondria hydrogenosomes: (1) are surrounded by two closely apposed membranes and present a granular matrix: (2) divide in three different ways: segmentation, partition and the heart form; (3) they may divide at any phase of the cell cycle; (4) produce ATP; (5) participate in the metabolism of pyruvate formed during glycolysis; (6) are the site of molecular hydrogen formation; (7) present a relationship with the endoplasmic reticulum; (8) incorporate calcium; (9) import proteins post-translationally; (10) present cardiolipin. However, there are differences, such as: (1) absence of genetic material, at least in trichomonas; (2) lack a respiratory chain and cytochromes; (3) absence of the F(0)-F(1) ATPase; (4) absence of the tricarboxylic acid cycle; (5) lack of oxidative phosphorylation; (6) presence of peripheral vesicles. Hydrogenosomes are considered an excellent drug target since their metabolic pathway is distinct from those found in mitochondria and thus medicines directed to these organelles will probably not affect the host-cell. The main drug used against trichomonads is metronidazole, although other drugs such as beta-Lapachone, colchicine, Taxol, nocodazole, griseofulvin, cytochalasins, hydroxyurea, among others, have been used in trichomonad studies, showing: (1) flagella internalization forming pseudocyst; (2) dysfunctional hydrogenosomes; (3) hydrogenosomes with abnormal sizes and shapes and with an electron dense deposit called nucleoid; (4) intense autophagy in which hydrogenosomes are removed and further digested in lysosomes. PMID:18473836

  17. Multi-Target Drugs: The Trend of Drug Research and Development

    OpenAIRE

    Jin-Jian Lu; Wei Pan; Yuan-Jia Hu; Yi-Tao Wang

    2012-01-01

    Summarizing the status of drugs in the market and examining the trend of drug research and development is important in drug discovery. In this study, we compared the drug targets and the market sales of the new molecular entities approved by the U.S. Food and Drug Administration from January 2000 to December 2009. Two networks, namely, the target-target and drug-drug networks, have been set up using the network analysis tools. The multi-target drugs have much more potential, as shown by the n...

  18. The drug target genes show higher evolutionary conservation than non-target genes.

    Science.gov (United States)

    Lv, Wenhua; Xu, Yongdeng; Guo, Yiying; Yu, Ziqi; Feng, Guanglong; Liu, Panpan; Luan, Meiwei; Zhu, Hongjie; Liu, Guiyou; Zhang, Mingming; Lv, Hongchao; Duan, Lian; Shang, Zhenwei; Li, Jin; Jiang, Yongshuai; Zhang, Ruijie

    2016-01-26

    Although evidence indicates that drug target genes share some common evolutionary features, there have been few studies analyzing evolutionary features of drug targets from an overall level. Therefore, we conducted an analysis which aimed to investigate the evolutionary characteristics of drug target genes. We compared the evolutionary conservation between human drug target genes and non-target genes by combining both the evolutionary features and network topological properties in human protein-protein interaction network. The evolution rate, conservation score and the percentage of orthologous genes of 21 species were included in our study. Meanwhile, four topological features including the average shortest path length, betweenness centrality, clustering coefficient and degree were considered for comparison analysis. Then we got four results as following: compared with non-drug target genes, 1) drug target genes had lower evolutionary rates; 2) drug target genes had higher conservation scores; 3) drug target genes had higher percentages of orthologous genes and 4) drug target genes had a tighter network structure including higher degrees, betweenness centrality, clustering coefficients and lower average shortest path lengths. These results demonstrate that drug target genes are more evolutionarily conserved than non-drug target genes. We hope that our study will provide valuable information for other researchers who are interested in evolutionary conservation of drug targets.

  19. Identifying mechanism-of-action targets for drugs and probes.

    Science.gov (United States)

    Gregori-Puigjané, Elisabet; Setola, Vincent; Hert, Jérôme; Crews, Brenda A; Irwin, John J; Lounkine, Eugen; Marnett, Lawrence; Roth, Bryan L; Shoichet, Brian K

    2012-07-10

    Notwithstanding their key roles in therapy and as biological probes, 7% of approved drugs are purported to have no known primary target, and up to 18% lack a well-defined mechanism of action. Using a chemoinformatics approach, we sought to "de-orphanize" drugs that lack primary targets. Surprisingly, targets could be easily predicted for many: Whereas these targets were not known to us nor to the common databases, most could be confirmed by literature search, leaving only 13 Food and Drug Administration-approved drugs with unknown targets; the number of drugs without molecular targets likely is far fewer than reported. The number of worldwide drugs without reasonable molecular targets similarly dropped, from 352 (25%) to 44 (4%). Nevertheless, there remained at least seven drugs for which reasonable mechanism-of-action targets were unknown but could be predicted, including the antitussives clemastine, cloperastine, and nepinalone; the antiemetic benzquinamide; the muscle relaxant cyclobenzaprine; the analgesic nefopam; and the immunomodulator lobenzarit. For each, predicted targets were confirmed experimentally, with affinities within their physiological concentration ranges. Turning this question on its head, we next asked which drugs were specific enough to act as chemical probes. Over 100 drugs met the standard criteria for probes, and 40 did so by more stringent criteria. A chemical information approach to drug-target association can guide therapeutic development and reveal applications to probe biology, a focus of much current interest. PMID:22711801

  20. Drug target identification using side-effect similarity

    DEFF Research Database (Denmark)

    Campillos, Monica; Kuhn, Michael; Gavin, Anne-Claude;

    2008-01-01

    Targets for drugs have so far been predicted on the basis of molecular or cellular features, for example, by exploiting similarity in chemical structure or in activity across cell lines. We used phenotypic side-effect similarities to infer whether two drugs share a target. Applied to 746 marketed...... drugs, a network of 1018 side effect-driven drug-drug relations became apparent, 261 of which are formed by chemically dissimilar drugs from different therapeutic indications. We experimentally tested 20 of these unexpected drug-drug relations and validated 13 implied drug-target relations by in vitro...... binding assays, of which 11 reveal inhibition constants equal to less than 10 micromolar. Nine of these were tested and confirmed in cell assays, documenting the feasibility of using phenotypic information to infer molecular interactions and hinting at new uses of marketed drugs....

  1. Prediction of Drug-Target Interactions for Drug Repositioning Only Based on Genomic Expression Similarity

    OpenAIRE

    Kejian Wang; Jiazhi Sun; Shufeng Zhou; Chunling Wan; Shengying Qin; Can Li; Lin He; Lun Yang

    2013-01-01

    Small drug molecules usually bind to multiple protein targets or even unintended off-targets. Such drug promiscuity has often led to unwanted or unexplained drug reactions, resulting in side effects or drug repositioning opportunities. So it is always an important issue in pharmacology to identify potential drug-target interactions (DTI). However, DTI discovery by experiment remains a challenging task, due to high expense of time and resources. Many computational methods are therefore develop...

  2. Identifying drug-target proteins based on network features

    Institute of Scientific and Technical Information of China (English)

    ZHU MingZhu; GAO Lei; LI Xia; LIU ZhiCheng

    2009-01-01

    Proteins rarely function in isolation Inside and outside cells, but operate as part of a highly Intercon-nected cellular network called the interaction network. Therefore, the analysis of the properties of drug-target proteins in the biological network is especially helpful for understanding the mechanism of drug action In terms of informatice. At present, no detailed characterization and description of the topological features of drug-target proteins have been available in the human protein-protein interac-tion network. In this work, by mapping the drug-targets in DrugBank onto the interaction network of human proteins, five topological indices of drug-targets were analyzed and compared with those of the whole protein interactome set and the non-drug-target set. The experimental results showed that drug-target proteins have higher connectivity and quicker communication with each other in the PPI network. Based on these features, all proteins In the interaction network were ranked. The results showed that, of the top 100 proteins, 48 are covered by DrugBank; of the remaining 52 proteins, 9 are drug-target proteins covered by the TTD, Matador and other databases, while others have been dem-onstrated to be drug-target proteins in the literature.

  3. Identifying drug-target proteins based on network features

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Proteins rarely function in isolation inside and outside cells, but operate as part of a highly intercon- nected cellular network called the interaction network. Therefore, the analysis of the properties of drug-target proteins in the biological network is especially helpful for understanding the mechanism of drug action in terms of informatics. At present, no detailed characterization and description of the topological features of drug-target proteins have been available in the human protein-protein interac- tion network. In this work, by mapping the drug-targets in DrugBank onto the interaction network of human proteins, five topological indices of drug-targets were analyzed and compared with those of the whole protein interactome set and the non-drug-target set. The experimental results showed that drug-target proteins have higher connectivity and quicker communication with each other in the PPI network. Based on these features, all proteins in the interaction network were ranked. The results showed that, of the top 100 proteins, 48 are covered by DrugBank; of the remaining 52 proteins, 9 are drug-target proteins covered by the TTD, Matador and other databases, while others have been dem- onstrated to be drug-target proteins in the literature.

  4. MAGNETIC MICROSPHERES AS A TARGETED DRUG DELIVERY SYSTEM : A REVIEW

    Directory of Open Access Journals (Sweden)

    TARUN PATEL

    2012-06-01

    Full Text Available The in-vivo targeting of tumors with magnetic microspheres is currently realized through the applicationof external non-uniform magnetic fields generated by rare-earth permanent magnets or electromagnets.This technique can be applied to magnetically targeted cancer therapy, magnetic embolization therapywith magnetic particles that contain anticancer agent, such as chemotherapeutic drugs or therapeuticradioisotopes. Drug targeting is one way of local or regional antitumor treatment. Magneticallycontrolled drug targeting is one of the various possible ways of drug targeting. This technology is basedon binding establish anticancer drug with ferrofluids that concentrate the drug in the area of interest(tumor site by means of magnetic fields. There has been keen interest in the development of amagnetically target drug delivery system. These drug delivery systems aims to deliver the drug at a ratedirected by the needs of the body during the period of treatment, and target the activity entity to the siteof action. This paper gives an overview of current application of magnetic microspheres (ferrofluid inconjunction with magnetic fields as they relate to the latest advances in medical application and inparticular to anticancer therapy and also discuss about mechanism of magnetic targeted delivery, drugrelease rate in-vitro, benefits and drawbacks of magnetic targeting.

  5. Killing cancer cells by targeted drug-carrying phage nanomedicines

    Directory of Open Access Journals (Sweden)

    Yacoby Iftach

    2008-04-01

    Full Text Available Abstract Background Systemic administration of chemotherapeutic agents, in addition to its anti-tumor benefits, results in indiscriminate drug distribution and severe toxicity. This shortcoming may be overcome by targeted drug-carrying platforms that ferry the drug to the tumor site while limiting exposure to non-target tissues and organs. Results We present a new form of targeted anti-cancer therapy in the form of targeted drug-carrying phage nanoparticles. Our approach is based on genetically-modified and chemically manipulated filamentous bacteriophages. The genetic manipulation endows the phages with the ability to display a host-specificity-conferring ligand. The phages are loaded with a large payload of a cytotoxic drug by chemical conjugation. In the presented examples we used anti ErbB2 and anti ERGR antibodies as targeting moieties, the drug hygromycin conjugated to the phages by a covalent amide bond, or the drug doxorubicin conjugated to genetically-engineered cathepsin-B sites on the phage coat. We show that targeting of phage nanomedicines via specific antibodies to receptors on cancer cell membranes results in endocytosis, intracellular degradation, and drug release, resulting in growth inhibition of the target cells in vitro with a potentiation factor of >1000 over the corresponding free drugs. Conclusion The results of the proof-of concept study presented here reveal important features regarding the potential of filamentous phages to serve as drug-delivery platform, on the affect of drug solubility or hydrophobicity on the target specificity of the platform and on the effect of drug release mechanism on the potency of the platform. These results define targeted drug-carrying filamentous phage nanoparticles as a unique type of antibody-drug conjugates.

  6. Anti-malarial Drug Design by Targeting Apicoplasts: New Perspectives

    Directory of Open Access Journals (Sweden)

    Avinaba Mukherjee

    2016-03-01

    Full Text Available Objectives: Malaria has been a major global health problem in recent times with increasing mortality. Current treatment methods include parasiticidal drugs and vaccinations. However, resistance among malarial parasites to the existing drugs has emerged as a significant area of concern in anti-malarial drug design. Researchers are now desperately looking for new targets to develop anti-malarials drug which is more target specific. Malarial parasites harbor a plastid-like organelle known as the ‘apicoplast’, which is thought to provide an exciting new outlook for the development of drugs to be used against the parasite. This review elaborates on the current state of development of novel compounds targeted againstemerging malaria parasites. Methods: The apicoplast, originates by an endosymbiotic process, contains a range of metabolic pathways and housekeeping processes that differ from the host body and thereby presents ideal strategies for anti-malarial drug therapy. Drugs are designed by targeting the unique mechanism of the apicoplasts genetic machinery. Several anabolic and catabolic processes, like fatty acid, isopenetyl diphosphate and heme synthess in this organelle, have also been targeted by drugs. Results: Apicoplasts offer exciting opportunities for the development of malarial treatment specific drugs have been found to act by disrupting this organelle’s function, which wouldimpede the survival of the parasite. Conclusion: Recent advanced drugs, their modes of action, and their advantages in the treatment of malaria by using apicoplasts as a target are discussed in this review which thought to be very useful in desigining anti-malarial drugs. Targetting the genetic machinery of apicoplast shows a great advantange regarding anti-malarial drug design. Critical knowledge of these new drugs would give a healthier understanding for deciphering the mechanism of action of anti-malarial drugs when targeting apicoplasts to overcome drug

  7. Assessing drug target association using semantic linked data.

    Directory of Open Access Journals (Sweden)

    Bin Chen

    Full Text Available The rapidly increasing amount of public data in chemistry and biology provides new opportunities for large-scale data mining for drug discovery. Systematic integration of these heterogeneous sets and provision of algorithms to data mine the integrated sets would permit investigation of complex mechanisms of action of drugs. In this work we integrated and annotated data from public datasets relating to drugs, chemical compounds, protein targets, diseases, side effects and pathways, building a semantic linked network consisting of over 290,000 nodes and 720,000 edges. We developed a statistical model to assess the association of drug target pairs based on their relation with other linked objects. Validation experiments demonstrate the model can correctly identify known direct drug target pairs with high precision. Indirect drug target pairs (for example drugs which change gene expression level are also identified but not as strongly as direct pairs. We further calculated the association scores for 157 drugs from 10 disease areas against 1683 human targets, and measured their similarity using a [Formula: see text] score matrix. The similarity network indicates that drugs from the same disease area tend to cluster together in ways that are not captured by structural similarity, with several potential new drug pairings being identified. This work thus provides a novel, validated alternative to existing drug target prediction algorithms. The web service is freely available at: http://chem2bio2rdf.org/slap.

  8. Assessing drug target association using semantic linked data.

    Science.gov (United States)

    Chen, Bin; Ding, Ying; Wild, David J

    2012-01-01

    The rapidly increasing amount of public data in chemistry and biology provides new opportunities for large-scale data mining for drug discovery. Systematic integration of these heterogeneous sets and provision of algorithms to data mine the integrated sets would permit investigation of complex mechanisms of action of drugs. In this work we integrated and annotated data from public datasets relating to drugs, chemical compounds, protein targets, diseases, side effects and pathways, building a semantic linked network consisting of over 290,000 nodes and 720,000 edges. We developed a statistical model to assess the association of drug target pairs based on their relation with other linked objects. Validation experiments demonstrate the model can correctly identify known direct drug target pairs with high precision. Indirect drug target pairs (for example drugs which change gene expression level) are also identified but not as strongly as direct pairs. We further calculated the association scores for 157 drugs from 10 disease areas against 1683 human targets, and measured their similarity using a [Formula: see text] score matrix. The similarity network indicates that drugs from the same disease area tend to cluster together in ways that are not captured by structural similarity, with several potential new drug pairings being identified. This work thus provides a novel, validated alternative to existing drug target prediction algorithms. The web service is freely available at: http://chem2bio2rdf.org/slap.

  9. Repurposing Drugs to Target the Diabetes Epidemic.

    Science.gov (United States)

    Turner, Nigel; Zeng, Xiao-Yi; Osborne, Brenna; Rogers, Suzanne; Ye, Ji-Ming

    2016-05-01

    Despite major investment by pharmaceutical companies in conventional drug discovery pipelines, development of new drugs has failed to keep up with the increasing incidence of many diseases, including type 2 diabetes (T2D). Drug repurposing, where existing drugs are applied to a new indication, is gaining momentum as a successful approach to overcome the bottlenecks commonly encountered with conventional approaches. Repurposing takes advantage of available information on the molecular pharmacology of clinical agents to drastically shorten drug development timelines. This review discusses recent advances in the discovery of new antidiabetic agents using repurposing strategies. PMID:26900045

  10. Identification of Multiple Cryptococcal Fungicidal Drug Targets by Combined Gene Dosing and Drug Affinity Responsive Target Stability Screening

    Directory of Open Access Journals (Sweden)

    Yoon-Dong Park

    2016-08-01

    Full Text Available Cryptococcus neoformans is a pathogenic fungus that is responsible for up to half a million cases of meningitis globally, especially in immunocompromised individuals. Common fungistatic drugs, such as fluconazole, are less toxic for patients but have low efficacy for initial therapy of the disease. Effective therapy against the disease is provided by the fungicidal drug amphotericin B; however, due to its high toxicity and the difficulty in administering its intravenous formulation, it is imperative to find new therapies targeting the fungus. The antiparasitic drug bithionol has been recently identified as having potent fungicidal activity. In this study, we used a combined gene dosing and drug affinity responsive target stability (GD-DARTS screen as well as protein modeling to identify a common drug binding site of bithionol within multiple NAD-dependent dehydrogenase drug targets. This combination genetic and proteomic method thus provides a powerful method for identifying novel fungicidal drug targets for further development.

  11. Identification of Multiple Cryptococcal Fungicidal Drug Targets by Combined Gene Dosing and Drug Affinity Responsive Target Stability Screening

    Science.gov (United States)

    Park, Yoon-Dong; Sun, Wei; Salas, Antonio; Antia, Avan; Carvajal, Cindy; Wang, Amy; Xu, Xin; Meng, Zhaojin; Zhou, Ming; Tawa, Gregory J.; Dehdashti, Jean; Zheng, Wei; Henderson, Christina M.; Zelazny, Adrian M.

    2016-01-01

    ABSTRACT Cryptococcus neoformans is a pathogenic fungus that is responsible for up to half a million cases of meningitis globally, especially in immunocompromised individuals. Common fungistatic drugs, such as fluconazole, are less toxic for patients but have low efficacy for initial therapy of the disease. Effective therapy against the disease is provided by the fungicidal drug amphotericin B; however, due to its high toxicity and the difficulty in administering its intravenous formulation, it is imperative to find new therapies targeting the fungus. The antiparasitic drug bithionol has been recently identified as having potent fungicidal activity. In this study, we used a combined gene dosing and drug affinity responsive target stability (GD-DARTS) screen as well as protein modeling to identify a common drug binding site of bithionol within multiple NAD-dependent dehydrogenase drug targets. This combination genetic and proteomic method thus provides a powerful method for identifying novel fungicidal drug targets for further development. PMID:27486194

  12. Hydrodynamic modeling of ferrofluid flow in magnetic targeting drug delivery

    Institute of Scientific and Technical Information of China (English)

    LIU Han-dan; XU Wei; WANG Shi-gang; KE Zun-ji

    2008-01-01

    Among the proposed techniques for delivering drugs to specific locations within human body, magnetic drug targeting prevails due to its non-invasive character and its high targeting efficiency. Magnetic targeting drug delivery is a method of carrying drug-loaded magnetic nanoparticles to a target tissue target under the applied magnetic field. This method increases the drug concentration in the target while reducing the adverse side-effects. Although there have been some theoretical analyses for magnetic drug targeting, very few researchers have addressed the hydrodynamic models of magnetic fluids in the blood vessel. A mathematical model is presented to describe the hydrodynamics of ferrofluids as drug carriers flowing in a blood vessel under the applied magnetic field. In this model, magnetic force and asymmetrical force are added, and an angular momentum equation of magnetic nanoparticles in the applied magnetic field is modeled. Engineering approximations are achieved by retaining the physically most significant items in the model due to the mathematical complexity of the motion equations. Numerical simulations are performed to obtain better insight into the theoretical model with computational fluid dynamics. Simulation results demonstrate the important parameters leading to adequate drug delivery to the target site depending on the magnetic field intensity, which coincident with those of animal experiments. Results of the analysis provide important information and suggest strategies for improving delivery in clinical application.

  13. Large-scale prediction of drug-target relationships

    DEFF Research Database (Denmark)

    Kuhn, Michael; Campillos, Mónica; González, Paula;

    2008-01-01

    also provides a more global view on drug-target relations. Here we review recent attempts to apply large-scale computational analyses to predict novel interactions of drugs and targets from molecular and cellular features. In this context, we quantify the family-dependent probability of two proteins to...

  14. NIOSOMES IN TARGETED DRUG DELIVERY : A REVIEW

    Directory of Open Access Journals (Sweden)

    PRAGNA GADHIYA

    2012-05-01

    Full Text Available Over the past several years, treatment of infectious diseases and immunization has undergone aparadigm shift. Stemming from the nanobiotechnology research, not only a large number of diseasespecificbiologicals have been developed, but also enormous efforts have been made to effectivelydeliver these biologicals. Non-ionic surfactant vesicles (or niosomes are now widely studied asalternates to liposomes. Different novel approaches used for delivering these drugs include liposomes,Microspheres, nanotechnology, micro emulsions, antibody-loaded drug delivery, magneticMicrocapsules, implantable pumps and niosomes. Niosomes and liposomes are equiactive In drugdelivery potential and both increase drug efficacy as compared with that of free Drug. Niosomes arepreferred over liposomes because the former exhibit high chemical Stability and economy. Niosomes areself assembled vesicles composed primarily of synthetic surfactants and cholesterol. They are analogousin structure to the more widely studied liposomes formed from biologically derived phospholipids.Niosomes represent an emerging class of novel vesicular systems. Niosome formation requires thepresence of a particular class of amphiphile and aqueous solvent. In recent years a comprehensiveresearch carried over niosome as a drug carrier. Various drugs are enlisted and tried in niosomesurfactant vesicles. Niosome appears to be a Well preferred drug delivery system over liposome asniosome being stable and economic. Also niosomes have great drug delivery potential for targeteddelivery of anti-cancer, Anti-infective agents. Drug delivery potential of niosome can enhance by usingnovel Concepts like proniosomes, discomes and aspasome. Niosomes also serve better aid in diagnosticimaging and as a vaccine adjuvant.

  15. Identifying mechanism-of-action targets for drugs and probes

    OpenAIRE

    Gregori-Puigjané, Elisabet; Setola, Vincent; Hert, Jérôme; Crews, Brenda A.; Irwin, John J.; Lounkine, Eugen; Marnett, Lawrence; Roth, Bryan L.; Brian K Shoichet

    2012-01-01

    Notwithstanding their key roles in therapy and as biological probes, 7% of approved drugs are purported to have no known primary target, and up to 18% lack a well-defined mechanism of action. Using a chemoinformatics approach, we sought to “de-orphanize” drugs that lack primary targets. Surprisingly, targets could be easily predicted for many: Whereas these targets were not known to us nor to the common databases, most could be confirmed by literature search, leaving only 13 Food and Drug Adm...

  16. Targeted electrohydrodynamic printing for micro-reservoir drug delivery systems

    International Nuclear Information System (INIS)

    Microfluidic drug delivery systems consisting of a drug reservoir and microfluidic channels have shown the possibility of simple and robust modulation of drug release rate. However, the difficulty of loading a small quantity of drug into drug reservoirs at a micro-scale limited further development of such systems. Electrohydrodynamic (EHD) printing was employed to fill micro-reservoirs with controlled amount of drugs in the range of a few hundreds of picograms to tens of micrograms with spatial resolution of as small as 20 µm. Unlike most EHD systems, this system was configured in combination with an inverted microscope that allows in situ targeting of drug loading at micrometer scale accuracy. Methylene blue and rhodamine B were used as model drugs in distilled water, isopropanol and a polymer solution of a biodegradable polymer and dimethyl sulfoxide (DMSO). Also tetracycline-HCl/DI water was used as actual drug ink. The optimal parameters of EHD printing to load an extremely small quantity of drug into microscale drug reservoirs were investigated by changing pumping rates, the strength of an electric field and drug concentration. This targeted EHD technique was used to load drugs into the microreservoirs of PDMS microfluidic drug delivery devices and their drug release performance was demonstrated in vitro. (paper)

  17. Drugs acting on central nervous system (CNS) targets as leads for non-CNS targets

    OpenAIRE

    Kharkar, Prashant S.

    2014-01-01

    Innovative drug discovery approaches are currently needed to rejuvenate the shrinking product pipelines of the pharmaceutical companies across the globe. Here a theme is presented – the use of central nervous system (CNS) drugs as leads for non-CNS targets. The approach is related to the use of existing drugs for new indications. Suitable chemical modifications of the CNS drugs abolish their CNS penetration. These novel analogs may then be screened for activity against non-CNS targets. Carefu...

  18. Targeted liposomal drug delivery to monocytes and macrophages.

    OpenAIRE

    Ciara Kelly; Caroline Jefferies; Sally-Ann Cryan

    2011-01-01

    As the role of monocytes and macrophages in a range of diseases is better understood, strategies to target these cell types are of growing importance both scientifically and therapeutically. As particulate carriers, liposomes naturally target cells of the mononuclear phagocytic system (MPS), particularly macrophages. Loading drugs into liposomes can therefore offer an efficient means of drug targeting to MPS cells. Physicochemical properties including size, charge and lipid composition can ha...

  19. Polymeric micelles for solubilization and targeting of hydrophobic drugs

    OpenAIRE

    Miller, Tobias

    2013-01-01

    This thesis focussed on the encapsulation of hydrophobic drugs into polymeric micelles and was intended to show the strengths and limitations of these self-assembling systems in terms of solubilization and drug targeting. Characterization of hydrophobic drug solubilization prior to intravenous injection was one of the key goals of this thesis. For this purpose a novel drug loading procedure was developed based on mechanistic considerations during the loading processes (Chapter 2). The cosolve...

  20. Magnetic polymer nanospheres for anticancer drug targeting

    Energy Technology Data Exchange (ETDEWEB)

    JurIkova, A; Csach, K; Koneracka, M; Zavisova, V; Tomasovicova, N; Lancz, G; Kopcansky, P; Timko, M; Miskuf, J [Institute of Experimental Physics, Slovak Academy of Sciences, 040 01 Kosice (Slovakia); Muckova, M, E-mail: akasard@saske.s [Hameln rds a.s., 900 01 Modra (Slovakia)

    2010-01-01

    Poly(D,L-lactide-co-glycolide) polymer (PLGA) nanospheres loaded with biocom-patible magnetic fluid as a magnetic carrier and anticancer drug Taxol were prepared by the modified nanoprecipitation method with size of 200-250 nm in diameter. The PLGA polymer was utilized as a capsulation material due to its biodegradability and biocompatibility. Taxol as an important anticancer drug was chosen for its significant role against a wide range of tumours. Thermal properties of the drug-polymer system were characterized using thermal analysis methods. It was determined the solubility of Taxol in PLGA nanospheres. Magnetic properties investigated using SQUID magnetometry showed superparamagnetism of the prepared magnetic polymer nanospheres.

  1. Drug Repurposing: Far Beyond New Targets for Old Drugs

    DEFF Research Database (Denmark)

    Oprea, Tudor; Mestres, J.

    2012-01-01

    Repurposing drugs requires finding novel therapeutic indications compared to the ones for which they were already approved. This is an increasingly utilized strategy for finding novel medicines, one that capitalizes on previous investments while derisking clinical activities. This approach...

  2. Targeted drug induces responses in aggressive lymphomas

    Science.gov (United States)

    Preliminary results from clinical trials in a subtype of lymphoma show that for a number of patients whose disease was not cured by other treatments, the drug ibrutinib can provide significant anti-cancer responses with modest side effects.

  3. Limited Efficiency of Drug Delivery to Specific Intracellular Organelles Using Subcellularly "Targeted" Drug Delivery Systems.

    Science.gov (United States)

    Maity, Amit Ranjan; Stepensky, David

    2016-01-01

    Many drugs have been designed to act on intracellular targets and to affect intracellular processes inside target cells. For the desired effects to be exerted, these drugs should permeate target cells and reach specific intracellular organelles. This subcellular drug targeting approach has been proposed for enhancement of accumulation of these drugs in target organelles and improved efficiency. This approach is based on drug encapsulation in drug delivery systems (DDSs) and/or their decoration with specific targeting moieties that are intended to enhance the drug/DDS accumulation in the intracellular organelle of interest. During recent years, there has been a constant increase in interest in DDSs targeted to specific intracellular organelles, and many different approaches have been proposed for attaining efficient drug delivery to specific organelles of interest. However, it appears that in many studies insufficient efforts have been devoted to quantitative analysis of the major formulation parameters of the DDSs disposition (efficiency of DDS endocytosis and endosomal escape, intracellular trafficking, and efficiency of DDS delivery to the target organelle) and of the resulting pharmacological effects. Thus, in many cases, claims regarding efficient delivery of drug/DDS to a specific organelle and efficient subcellular targeting appear to be exaggerated. On the basis of the available experimental data, it appears that drugs/DDS decoration with specific targeting residues can affect their intracellular fate and result in preferential drug accumulation within an organelle of interest. However, it is not clear whether these approaches will be efficient in in vivo settings and be translated into preclinical and clinical applications. Studies that quantitatively assess the mechanisms, barriers, and efficiencies of subcellular drug delivery and of the associated toxic effects are required to determine the therapeutic potential of subcellular DDS targeting.

  4. Transcription factors as targets of anticancer drugs.

    Science.gov (United States)

    Gniazdowski, M; Czyz, M

    1999-01-01

    Several general and gene- and cell-selective transcription factors are required for specific transcription to occur. Many of them exert their functions through specific contacts either in the promoter region or at distant sequences regulating the initiation. These contacts may be altered by anticancer drugs which form non-covalent complexes with DNA. Covalent modifications of DNA by alkylating agents may prevent transcription factors from recognizing their specific sequences or may constitute multiple "unnatural" binding sites in DNA which attract the factors thus decreasing their availability in the cell. The anticancer drug-transcription factor interplay which is based on specific interactions with DNA may contribute to pharmacological properties of the former and provide a basis for the search for new drugs. PMID:10547027

  5. A review on target drug delivery:magnetic microspheres

    Institute of Scientific and Technical Information of China (English)

    Amit Chandna; Deepa Batra; Satinder Kakar; Ramandeep Singh

    2013-01-01

    Novel drug delivery system aims to deliver the drug at a rate directed by the needs of the body during the period of treatment, and target the active entity to the site of action.A number of novel drug delivery systems have emerged encompassing various routes of administration, to achieve controlled and targeted drug delivery, magnetic micro carriers being one of them. Magnetic microsphere is newer approach in pharmaceutical field.Magnetic microspheres as an alternative to traditional radiation methods which use highly penetrating radiation that is absorbed throughout the body.Its use is limited by toxicity and side effects.The aim of the specific targeting is to enhance the efficiency of drug delivery & at the same time to reduce the toxicity & side effects.This kind of delivery system is very much important which localises the drug to the disease site.In this larger amount of freely circulating drug can be replaced by smaller amount of magnetically targeted drug.Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microspheres are chitosan, dextran etc. magnetic microspheres can be prepared from a variety of carrier material. One of the most utilized is serum albumin from human or other appropriate species.Drug release from albumin microspheres can be sustained or controlled by various stabilization procedures generally involving heat or chemical cross-linking of the protein carrier matrix.

  6. TargetNet: a web service for predicting potential drug-target interaction profiling via multi-target SAR models.

    Science.gov (United States)

    Yao, Zhi-Jiang; Dong, Jie; Che, Yu-Jing; Zhu, Min-Feng; Wen, Ming; Wang, Ning-Ning; Wang, Shan; Lu, Ai-Ping; Cao, Dong-Sheng

    2016-05-01

    Drug-target interactions (DTIs) are central to current drug discovery processes and public health fields. Analyzing the DTI profiling of the drugs helps to infer drug indications, adverse drug reactions, drug-drug interactions, and drug mode of actions. Therefore, it is of high importance to reliably and fast predict DTI profiling of the drugs on a genome-scale level. Here, we develop the TargetNet server, which can make real-time DTI predictions based only on molecular structures, following the spirit of multi-target SAR methodology. Naïve Bayes models together with various molecular fingerprints were employed to construct prediction models. Ensemble learning from these fingerprints was also provided to improve the prediction ability. When the user submits a molecule, the server will predict the activity of the user's molecule across 623 human proteins by the established high quality SAR model, thus generating a DTI profiling that can be used as a feature vector of chemicals for wide applications. The 623 SAR models related to 623 human proteins were strictly evaluated and validated by several model validation strategies, resulting in the AUC scores of 75-100 %. We applied the generated DTI profiling to successfully predict potential targets, toxicity classification, drug-drug interactions, and drug mode of action, which sufficiently demonstrated the wide application value of the potential DTI profiling. The TargetNet webserver is designed based on the Django framework in Python, and is freely accessible at http://targetnet.scbdd.com . PMID:27167132

  7. Leveraging Big Data to Transform Target Selection and Drug Discovery

    Science.gov (United States)

    Chen, B; Butte, AJ

    2016-01-01

    The advances of genomics, sequencing, and high throughput technologies have led to the creation of large volumes of diverse datasets for drug discovery. Analyzing these datasets to better understand disease and discover new drugs is becoming more common. Recent open data initiatives in basic and clinical research have dramatically increased the types of data available to the public. The past few years have witnessed successful use of big data in many sectors across the whole drug discovery pipeline. In this review, we will highlight the state of the art in leveraging big data to identify new targets, drug indications, and drug response biomarkers in this era of precision medicine. PMID:26659699

  8. Leveraging big data to transform target selection and drug discovery

    Science.gov (United States)

    Butte, AJ

    2016-01-01

    The advances of genomics, sequencing, and high throughput technologies have led to the creation of large volumes of diverse datasets for drug discovery. Analyzing these datasets to better understand disease and discover new drugs is becoming more common. Recent open data initiatives in basic and clinical research have dramatically increased the types of data available to the public. The past few years have witnessed successful use of big data in many sectors across the whole drug discovery pipeline. In this review, we will highlight the state of the art in leveraging big data to identify new targets, drug indications, and drug response biomarkers in this era of precision medicine. PMID:26659699

  9. Mitochondrial drug targets in neurodegenerative diseases.

    Science.gov (United States)

    Lee, Jiyoun

    2016-02-01

    Growing evidence suggests that mitochondrial dysfunction is the main culprit in neurodegenerative diseases. Given the fact that mitochondria participate in diverse cellular processes, including energetics, metabolism, and death, the consequences of mitochondrial dysfunction in neuronal cells are inevitable. In fact, new strategies targeting mitochondrial dysfunction are emerging as potential alternatives to current treatment options for neurodegenerative diseases. In this review, we focus on mitochondrial proteins that are directly associated with mitochondrial dysfunction. We also examine recently identified small molecule modulators of these mitochondrial targets and assess their potential in research and therapeutic applications.

  10. Decorating Nanoparticle Surface for Targeted Drug Delivery: Opportunities and Challenges

    OpenAIRE

    Zhiqiang Shen; Mu-Ping Nieh; Ying Li

    2016-01-01

    The size, shape, stiffness (composition) and surface properties of nanoparticles (NPs) have been recognized as key design parameters for NP-mediated drug delivery platforms. Among them, the surface functionalization of NPs is of great significance for targeted drug delivery. For instance, targeting moieties are covalently coated on the surface of NPs to improve their selectively and affinity to cancer cells. However, due to a broad range of possible choices of surface decorating molecules, it...

  11. Tumor targeting using liposomal antineoplastic drugs

    OpenAIRE

    Jörg Huwyler; Jürgen Drewe; Stephan Krähenbühl

    2008-01-01

    Jörg Huwyler1, Jürgen Drewe2, Stephan Krähenbühl21University of Applied Sciences Northwestern Switzerland, Institute of Pharma Technology, Muttenz, Switzerland; 2Department of Research and Division of Clinical Pharmacology, University Hospital Basel, Basel, SwitzerlandAbstract: During the last years, liposomes (microparticulate phospholipid vesicles) have beenused with growing success as pharmaceutical carriers for antineoplastic drugs. Fields of applicatio...

  12. Sequencing targeting insurgents and drugs in Colombia

    OpenAIRE

    Farrell, Michelle L.

    2007-01-01

    Colombia President Pastrana President Uribe Drug Trade Coca Counter-narcotics FARC FARC-EP Revolutionary Armed Forces of Colombia Government of Colombia Insurgency Terrorism Plan Colombia Plan Patriota Demilitarized Zone Democratic Defense and Security Policy DSP Peru's success in first defeating the Shining Path guerrilla movement in the early 1990s and then reducing coca cultivation in the mid-1990s demonstrates the effectiveness of a s...

  13. REVIEW ON ADVANCES IN COLON TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Sunena Sethi, SL Harikumar* and Nirmala

    2012-09-01

    Full Text Available The colon is the terminal part of the GIT which has gained in recent years as a potential site for delivery of various novel therapeutic drugs, i.e. peptides. However, colon is rich in microflora which can be used to target the drug release in the colon. Colon is a site where both local and systemic drug delivery can take place. Local delivery allows the topical treatment of inflammatory bowel disease. If drug can be targeted directly into the colon, treatment can become more effective and side effects can be minimized. These systemic side effects can be minimized by primary approaches for CDDS (Colon specific drug delivery namely prodrugs, pH and time dependent systems and microbially triggered system which gained limited success and have limitations as compared with recently new CDDS namely pressure controlled colon delivery capsules (PCDCS, CODESTM (Novel colon targeted delivery system osmotic controlled drug delivery system, Pulsincap system, time clock system, chronotropic system. This review is to understand the pharmaceutical approaches to colon targeted drug delivery systems for better therapeutic action without compromising on drug degradation (or its low bioavailability.

  14. Liposomes and nanotechnology in drug development: focus on ocular targets.

    Science.gov (United States)

    Honda, Miki; Asai, Tomohiro; Oku, Naoto; Araki, Yoshihiko; Tanaka, Minoru; Ebihara, Nobuyuki

    2013-01-01

    Poor drug delivery to lesions in patients' eyes is a major obstacle to the treatment of ocular diseases. The accessibility of these areas to drugs is highly restricted by the presence of barriers, including the corneal barrier, aqueous barrier, and the inner and outer blood-retinal barriers. In particular, the posterior segment is difficult to reach for drugs because of its structural peculiarities. This review discusses various barriers to drug delivery and provides comprehensive information for designing nanoparticle-mediated drug delivery systems for the treatment of ocular diseases. Nanoparticles can be designed to improve penetration, controlled release, and drug targeting. As highlighted in this review, the therapeutic efficacy of drugs in ocular diseases has been reported to be enhanced by the use of nanoparticles such as liposomes, micro/nanospheres, microemulsions, and dendrimers. Our recent data show that intravitreal injection of targeted liposomes encapsulating an angiogenesis inhibitor caused significantly greater suppression of choroidal neovascularization than did the injection of free drug. Recent progress in ocular drug delivery systems research has provided new insights into drug development, and the use of nanoparticles for drug delivery is thus a promising approach for advanced therapy of ocular diseases. PMID:23439842

  15. Design of Nanoparticle-Based Carriers for Targeted Drug Delivery

    OpenAIRE

    Xiaojiao Yu; Ian Trase; Muqing Ren; Kayla Duval; Xing Guo; Zi Chen

    2016-01-01

    Nanoparticles have shown promise as both drug delivery vehicles and direct antitumor systems, but they must be properly designed in order to maximize efficacy. Computational modeling is often used both to design new nanoparticles and to better understand existing ones. Modeled processes include the release of drugs at the tumor site and the physical interaction between the nanoparticle and cancer cells. In this paper, we provide an overview of three different targeted drug delivery methods (p...

  16. Prediction of drug-target interactions for drug repositioning only based on genomic expression similarity.

    Directory of Open Access Journals (Sweden)

    Kejian Wang

    Full Text Available Small drug molecules usually bind to multiple protein targets or even unintended off-targets. Such drug promiscuity has often led to unwanted or unexplained drug reactions, resulting in side effects or drug repositioning opportunities. So it is always an important issue in pharmacology to identify potential drug-target interactions (DTI. However, DTI discovery by experiment remains a challenging task, due to high expense of time and resources. Many computational methods are therefore developed to predict DTI with high throughput biological and clinical data. Here, we initiatively demonstrate that the on-target and off-target effects could be characterized by drug-induced in vitro genomic expression changes, e.g. the data in Connectivity Map (CMap. Thus, unknown ligands of a certain target can be found from the compounds showing high gene-expression similarity to the known ligands. Then to clarify the detailed practice of CMap based DTI prediction, we objectively evaluate how well each target is characterized by CMap. The results suggest that (1 some targets are better characterized than others, so the prediction models specific to these well characterized targets would be more accurate and reliable; (2 in some cases, a family of ligands for the same target tend to interact with common off-targets, which may help increase the efficiency of DTI discovery and explain the mechanisms of complicated drug actions. In the present study, CMap expression similarity is proposed as a novel indicator of drug-target interactions. The detailed strategies of improving data quality by decreasing the batch effect and building prediction models are also effectively established. We believe the success in CMap can be further translated into other public and commercial data of genomic expression, thus increasing research productivity towards valid drug repositioning and minimal side effects.

  17. Synthetic LDL as targeted drug delivery vehicle

    Science.gov (United States)

    Forte, Trudy M.; Nikanjam, Mina

    2012-08-28

    The present invention provides a synthetic LDL nanoparticle comprising a lipid moiety and a synthetic chimeric peptide so as to be capable of binding the LDL receptor. The synthetic LDL nanoparticle of the present invention is capable of incorporating and targeting therapeutics to cells expressing the LDL receptor for diseases associated with the expression of the LDL receptor such as central nervous system diseases. The invention further provides methods of using such synthetic LDL nanoparticles.

  18. Targeting autophagic pathways for cancer drug discovery

    Institute of Scientific and Technical Information of China (English)

    Bo Liu; Jin-Ku Bao; Jin-Ming Yang; Yan Cheng

    2013-01-01

    Autophagy,an evolutionarily conserved lysosomal degradation process,has drawn an increasing amount of attention in recent years for its role in a variety of human diseases,such as cancer.Notably,autophagy plays an important role in regulating several survival and death signaling pathways that determine cell fate in cancer.To date,substantial evidence has demonstrated that some key autophagic mediators,such as autophagy-related genes (ATGs),PI3K,mTOR,p53,and Beclin-1,may play crucial roles in modulating autophagic activity in cancer initiation and progression.Because autophagy-modulating agents such as rapamycin and chloroquine have already been used clinically to treat cancer,it is conceivable that targeting autophagic pathways may provide a new opportunity for discovery and development of more novel cancer therapeutics.With a deeper understanding of the regulatory mechanisms governing autophagy,we will have a better opportunity to facilitate the exploitation of autophagy as a target for therapeutic intervention in cancer.This review discusses the current status of targeting autophagic pathways as a potential cancer therapy.

  19. Preclinical validation of Aurora kinases-targeting drugs in osteosarcoma

    OpenAIRE

    Tavanti, E; Sero, V; Vella, S; M. Fanelli; Michelacci, F; Landuzzi, L; Magagnoli, G; Versteeg, R; Picci, P; Hattinger, C M; M. Serra

    2013-01-01

    Background: Aurora kinases are key regulators of cell cycle and represent new promising therapeutic targets in several human tumours. Methods: Biological relevance of Aurora kinase-A and -B was assessed on osteosarcoma clinical samples and by silencing these genes with specific siRNA in three human osteosarcoma cell lines. In vitro efficacy of two Aurora kinases-targeting drugs (VX-680 and ZM447439) was evaluated on a panel of four drug-sensitive and six drug-resistant human osteosarcoma cell...

  20. Glial cells as drug targets: What does it take?

    Science.gov (United States)

    Möller, Thomas; Boddeke, Hendrikus W G M

    2016-10-01

    The last two decades have brought a significant increase in our understanding of glial biology and glial contribution to CNS disease. Yet, despite the fact that glial cells make up the majority of CNS cells, no drug specifically targeting glial cells is on the market. Given the long development times of CNS drugs, on average over 12 years, this is not completely surprising. However, there is increasing interest from academia and industry to exploit glial targets to develop drugs for the benefit of patients with currently limited or no therapeutic options. CNS drug development has a high attrition rate and has encountered many challenges. It seems unlikely that developing drugs against glial targets would be any less demanding. However, the knowledge generated in traditional CNS drug discovery teaches valuable lessons, which could enable the glial community to accelerate the cycle time from basic discovery to drug development. In this review we will discuss steps necessary to bring a "glial target idea" to a clinical development program. GLIA 2016;64:1742-1754. PMID:27121701

  1. How do antimalarial drugs reach their intracellular targets?

    Directory of Open Access Journals (Sweden)

    Katherine eBasore

    2015-05-01

    Full Text Available Drugs represent the primary treatment available for human malaria, as caused by Plasmodium spp. Currently approved drugs and antimalarial drug leads generally work against parasite enzymes or activities within infected erythrocytes. To reach their specific targets, these chemicals must cross at least three membranes beginning with the host cell membrane. Uptake at each membrane may involve partitioning and diffusion through the lipid bilayer or facilitated transport through channels or carriers. Here, we review the features of available antimalarials and examine whether transporters may be required for their uptake. Our computational analysis suggests that most antimalarials have high intrinsic membrane permeability, obviating the need for uptake via transporters; a subset of compounds appear to require facilitated uptake. We also review parasite and host transporters that may contribute to drug uptake. Broad permeability channels at the erythrocyte and parasitophorous vacuolar membranes of infected cells relax permeability constraints on antimalarial drug design; however, this uptake mechanism is prone to acquired resistance as the parasite may alter channel activity to reduce drug uptake. A better understanding of how antimalarial drugs reach their intracellular targets is critical to prioritizing drug leads for antimalarial development and may reveal new targets for therapeutic intervention.

  2. A Computational Drug Repositioning Approach for Targeting Oncogenic Transcription Factors.

    Science.gov (United States)

    Gayvert, Kaitlyn M; Dardenne, Etienne; Cheung, Cynthia; Boland, Mary Regina; Lorberbaum, Tal; Wanjala, Jackline; Chen, Yu; Rubin, Mark A; Tatonetti, Nicholas P; Rickman, David S; Elemento, Olivier

    2016-06-14

    Mutations in transcription factor (TF) genes are frequently observed in tumors, often leading to aberrant transcriptional activity. Unfortunately, TFs are often considered undruggable due to the absence of targetable enzymatic activity. To address this problem, we developed CRAFTT, a computational drug-repositioning approach for targeting TF activity. CRAFTT combines ChIP-seq with drug-induced expression profiling to identify small molecules that can specifically perturb TF activity. Application to ENCODE ChIP-seq datasets revealed known drug-TF interactions, and a global drug-protein network analysis supported these predictions. Application of CRAFTT to ERG, a pro-invasive, frequently overexpressed oncogenic TF, predicted that dexamethasone would inhibit ERG activity. Dexamethasone significantly decreased cell invasion and migration in an ERG-dependent manner. Furthermore, analysis of electronic medical record data indicates a protective role for dexamethasone against prostate cancer. Altogether, our method provides a broadly applicable strategy for identifying drugs that specifically modulate TF activity. PMID:27264179

  3. Di/tri-peptide transporters as drug delivery targets

    DEFF Research Database (Denmark)

    Nielsen, C U; Brodin, Birger

    2003-01-01

    Two human di/tri-peptide transporters, hPepT1 and hPepT2 have been identified and functionally characterized. In the small intestine hPepT1 is exclusively expressed, whereas both PepT1 and PepT2 are expressed in the proximal tubule. The transport via di/tri-peptide transporters is proton-dependen....../tri-peptide transporters from vesicular storages 3) changes in gene transcription/mRNA stability. The aim of the present review is to discuss physiological, patho-physiological and drug-induced regulation of di/tri-peptide transporter mediated transport.......-dependent, and the transporters thus belong to the Proton-dependent Oligopeptide Transporter (POT)-family. The transporters are not drug targets per se, however due to their uniquely broad substrate specificity; they have proved to be relevant drug targets at the level of drug transport. Drug molecules such as oral active beta...

  4. Targeting efflux pumps to overcome antifungal drug resistance.

    Science.gov (United States)

    Holmes, Ann R; Cardno, Tony S; Strouse, J Jacob; Ivnitski-Steele, Irena; Keniya, Mikhail V; Lackovic, Kurt; Monk, Brian C; Sklar, Larry A; Cannon, Richard D

    2016-08-01

    Resistance to antifungal drugs is an increasingly significant clinical problem. The most common antifungal resistance encountered is efflux pump-mediated resistance of Candida species to azole drugs. One approach to overcome this resistance is to inhibit the pumps and chemosensitize resistant strains to azole drugs. Drug discovery targeting fungal efflux pumps could thus result in the development of azole-enhancing combination therapy. Heterologous expression of fungal efflux pumps in Saccharomyces cerevisiae provides a versatile system for screening for pump inhibitors. Fungal efflux pumps transport a range of xenobiotics including fluorescent compounds. This enables the use of fluorescence-based detection, as well as growth inhibition assays, in screens to discover compounds targeting efflux-mediated antifungal drug resistance. A variety of medium- and high-throughput screens have been used to identify a number of chemical entities that inhibit fungal efflux pumps. PMID:27463566

  5. Novel colon targeted drug delivery system using natural polymers

    Directory of Open Access Journals (Sweden)

    Ravi V

    2008-01-01

    Full Text Available A novel colon targeted tablet formulation was developed using pectin as carrier and diltiazem HCl and indomethacin as model drugs. The tablets were coated with inulin followed by shellac and were evaluated for average weight, hardness and coat thickness. In vitro release studies for prepared tablets were carried out for 2 h in pH 1.2 HCl buffer, 3 h in pH 7.4 phosphate buffer and 6 h in simulated colonic fluid. The drug release from the coated systems was monitored using UV/Vis spectroscopy. In vitro studies revealed that the tablets coated with inulin and shellac have limited the drug release in stomach and small intestinal environment and released maximum amount of drug in the colonic environment. The study revealed that polysaccharides as carriers and inulin and shellac as a coating material can be used effectively for colon targeting of both water soluble and insoluble drugs.

  6. Cytotoxicity of liver targeted drug-loaded aiginate nanoparticles

    Institute of Scientific and Technical Information of China (English)

    ZHANG ChuangNian; WANG Wei; WANG ChunHong; TIAN Qin; HUANG Wei; YUAN Zhi; CHEN XueSi

    2009-01-01

    In this study,novel liver targeted doxorubicin (DOX) loaded alginate (ALG) nanoparticles were prepared by CaCl2 crosslinking method.Glycyrrhetinic acid (GA,a liver targeted molecule) modified alginate (GA-ALG) was synthesized in a heterogeneous system,and the structure of GA-ALG and the substitution degree of GA were analyzed by 1H NMR,FT-IR and elemental analysis.The drug release profile under the simulated physiological condition and cytotoxicity experiments of drug-loaded GA-ALG nanoparticles were carried out in vitro.Transmission electron micrographs (TEM) and dynamic light scattering (DLS) analysis showed that drug-loaded GA-ALG nanoparticles have spherical shape structure with the mean hydrodynamic diameter around 214±11 nm.The drug release was shown to last 20 days,and the MTT assay suggested that drug-loaded GA-ALG nanoparticles had a distinct killing effect on 7703 hepatocellular carcinoma cells.

  7. Cytotoxicity of liver targeted drug-loaded alginate nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this study, novel liver targeted doxorubicin (DOX) loaded alginate (ALG) nanoparticles were prepared by CaCl2 crosslinking method. Glycyrrhetinic acid (GA, a liver targeted molecule) modified alginate (GA-ALG) was synthesized in a heterogeneous system, and the structure of GA-ALG and the substitu-tion degree of GA were analyzed by 1H NMR, FT-IR and elemental analysis. The drug release profile under the simulated physiological condition and cytotoxicity experiments of drug-loaded GA-ALG nanoparticles were carried out in vitro. Transmission electron micrographs (TEM) and dynamic light scattering (DLS) analysis showed that drug-loaded GA-ALG nanoparticles have spherical shape structure with the mean hydrodynamic diameter around 214 ± 11 nm. The drug release was shown to last 20 days, and the MTT assay suggested that drug-loaded GA-ALG nanoparticles had a distinct kill-ing effect on 7703 hepatocellular carcinoma cells.

  8. Nanostructured materials for selective recognition and targeted drug delivery

    International Nuclear Information System (INIS)

    Selective recognition requires the introduction of a molecular memory into a polymer matrix in order to make it capable of rebinding an analyte with a very high specificity. In addition, targeted drug delivery requires drug-loaded vesicles which preferentially localize to the sites of injury and avoid uptake into uninvolved tissues. The rapid evolution of nanotechnology is aiming to fulfill the goal of selective recognition and optimal drug delivery through the development of molecularly imprinted polymeric (MIP) nanoparticles, tailor-made for a diverse range of analytes (e.g., pharmaceuticals, pesticides, amino acids, etc.) and of nanostructured targeted drug carriers (e.g., liposomes and micelles) with increased circulation lifetimes. In the present study, PLGA microparticles containing multilamellar vesicles (MLVs), and MIP nanoparticles were synthesized to be employed as drug carriers and synthetic receptors respectively

  9. Drug Elucidation: Invertebrate Genetics Sheds New Light on the Molecular Targets of CNS Drugs

    Directory of Open Access Journals (Sweden)

    Donard S. Dwyer

    2014-07-01

    Full Text Available Many important drugs approved to treat common human diseases were discovered by serendipity, without a firm understanding of their modes of action. As a result, the side effects and interactions of these medications are often unpredictable, and there is limited guidance for improving the design of next-generation drugs. Here, we review the innovative use of simple model organisms, especially Caenorhabditis elegans, to gain fresh insights into the complex biological effects of approved CNS medications. Whereas drug discovery involves the identification of new drug targets and lead compounds/biologics, and drug development spans preclinical testing to FDA approval, drug elucidation refers to the process of understanding the mechanisms of action of marketed drugs by studying their novel effects in model organisms. Drug elucidation studies have revealed new pathways affected by antipsychotic drugs, e.g., the insulin signaling pathway, a trace amine receptor and a nicotinic acetylcholine receptor. Similarly, novel targets of antidepressant drugs and lithium have been identified in C. elegans, including lipid-binding/transport proteins and the SGK-1 signaling pathway, respectively. Elucidation of the mode of action of anesthetic agents has shown that anesthesia can involve mitochondrial targets, leak currents and gap junctions. The general approach reviewed in this article has advanced our knowledge about important drugs for CNS disorders and can guide future drug discovery efforts.

  10. Drug treatment and novel drug target against Cryptosporidium

    Directory of Open Access Journals (Sweden)

    Gargala G.

    2008-09-01

    Full Text Available Cryptosporidiosis emergence triggered the screening of many compounds for potential anti-cryptosporidial activity in which the majority were ineffective. The outbreak of cryptosporidiosis which occurred in Milwaukee in 1993 was not only the first significant emergence of Cryptosporidium spp. as a major human pathogen but also a huge waterborne outbreak thickening thousands of people from a major city in North America. Since then, outbreaks of cryptosporidiosis are regularly occurring throughout the world. New drugs against this parasite became consequently urgently needed. Among the most commonly used treatments against cryptosporidiosis are paromomycin, and azithromycin, which are partially effective. Nitazoxanide (NTZ’s effectiveness was demonstrated in vitro, and in vivo using several animal models and finally in clinical trials. It significantly shortened the duration of diarrhea and decreased mortality in adults and in malnourished children. NTZ is not effective without an appropriate immune response. In AIDS patients, combination therapy restoring immunity along with antimicrobial treatment of Cryptosporidium infection is necessary. Recent investigations focused on the potential of molecular-based immunotherapy against this parasite. Others tested the effects of probiotic bacteria, but were unable to demonstrate eradication of C. parvum. New synthetic isoflavone derivatives demonstrated excellent activity against C. parvum in vitro and in a gerbil model of infection. Newly synthesized nitroor non nitro- thiazolide compounds, derived from NTZ, have been recently shown to be at least as effective as NTZ against C. parvum in vitro development and are promising new therapeutic agents.

  11. Emerging targeted drug therapies in skeletal dysplasias.

    Science.gov (United States)

    Yap, Patrick; Savarirayan, Ravi

    2016-10-01

    Quantum advances have occurred in the field of human genetics in the six decades since Watson and Crick expressed their "wish to suggest a structure for the salt of deoxyribose nucleic acid." These culminated with the human genome project, which has opened up myriad possibilities, including that of individualized genetic medicine, the ability to deliver medical advice, management, and therapy tailored to an individual's genetic blueprint. Advances in genetic diagnostic capabilities have been rapid, to the point where the genome can be sequenced for several thousand dollars. Crucially, it has facilitated the identification of targets for "precision" treatments to combat genetic diseases at their source. This manuscript will review the innovative, pathogenesis-based therapies that are revolutionizing management of skeletal dysplasias, giving patients and families new options and outcomes. © 2016 Wiley Periodicals, Inc. PMID:27155200

  12. The sodium channel as a target for local anesthetic drugs

    Directory of Open Access Journals (Sweden)

    Harry A Fozzard

    2011-11-01

    Full Text Available Na channels are the source of excitatory currents for the nervous system and muscle. They are the target for a class of drugs called local anesthetics (LA, which have been used for local and regional anesthesia and for excitatory dysfunction problems such as epilepsy and cardiac arrhythmia. LA drugs are prototypes for new analgesic drugs. The LA drug binding site has been localized to the inner pore of the channel, where drugs interact mainly with a phenylalanine in domain IV S6. Drug affinity is both voltage- and use-dependent. Voltage-dependency is the result of changes in the conformation of the inner pore during channel activation and opening, allowing high energy interaction of drugs with the phenylalanine. LA drugs also reduce the gating current of Na channels, which represents the movement of charged residues in the voltage sensors. Specifically, drug binding to phenylalanine locks the domain III S4 in its outward (activated position, and slows recovery of the domain IV S4. Although strongly affecting gating, LA drugs almost certainly also block by steric occlusion of the pore. Molecular definition of the binding and blocking interactions may help in new drug development.

  13. Genomes2Drugs: identifies target proteins and lead drugs from proteome data.

    LENUS (Irish Health Repository)

    Toomey, David

    2009-01-01

    BACKGROUND: Genome sequencing and bioinformatics have provided the full hypothetical proteome of many pathogenic organisms. Advances in microarray and mass spectrometry have also yielded large output datasets of possible target proteins\\/genes. However, the challenge remains to identify new targets for drug discovery from this wealth of information. Further analysis includes bioinformatics and\\/or molecular biology tools to validate the findings. This is time consuming and expensive, and could fail to yield novel drugs if protein purification and crystallography is impossible. To pre-empt this, a researcher may want to rapidly filter the output datasets for proteins that show good homology to proteins that have already been structurally characterised or proteins that are already targets for known drugs. Critically, those researchers developing novel antibiotics need to select out the proteins that show close homology to any human proteins, as future inhibitors are likely to cross-react with the host protein, causing off-target toxicity effects later in clinical trials. METHODOLOGY\\/PRINCIPAL FINDINGS: To solve many of these issues, we have developed a free online resource called Genomes2Drugs which ranks sequences to identify proteins that are (i) homologous to previously crystallized proteins or (ii) targets of known drugs, but are (iii) not homologous to human proteins. When tested using the Plasmodium falciparum malarial genome the program correctly enriched the ranked list of proteins with known drug target proteins. CONCLUSIONS\\/SIGNIFICANCE: Genomes2Drugs rapidly identifies proteins that are likely to succeed in drug discovery pipelines. This free online resource helps in the identification of potential drug targets. Importantly, the program further highlights proteins that are likely to be inhibited by FDA-approved drugs. These drugs can then be rapidly moved into Phase IV clinical studies under \\'change-of-application\\' patents.

  14. Membrane Transporters: Structure, Function and Targets for Drug Design

    Science.gov (United States)

    Ravna, Aina W.; Sager, Georg; Dahl, Svein G.; Sylte, Ingebrigt

    Current therapeutic drugs act on four main types of molecular targets: enzymes, receptors, ion channels and transporters, among which a major part (60-70%) are membrane proteins. This review discusses the molecular structures and potential impact of membrane transporter proteins on new drug discovery. The three-dimensional (3D) molecular structure of a protein contains information about the active site and possible ligand binding, and about evolutionary relationships within the protein family. Transporters have a recognition site for a particular substrate, which may be used as a target for drugs inhibiting the transporter or acting as a false substrate. Three groups of transporters have particular interest as drug targets: the major facilitator superfamily, which includes almost 4000 different proteins transporting sugars, polyols, drugs, neurotransmitters, metabolites, amino acids, peptides, organic and inorganic anions and many other substrates; the ATP-binding cassette superfamily, which plays an important role in multidrug resistance in cancer chemotherapy; and the neurotransmitter:sodium symporter family, which includes the molecular targets for some of the most widely used psychotropic drugs. Recent technical advances have increased the number of known 3D structures of membrane transporters, and demonstrated that they form a divergent group of proteins with large conformational flexibility which facilitates transport of the substrate.

  15. Process Modeling of Ferrofluids Flowfor Magnetic Targeting Drug Delivery

    Institute of Scientific and Technical Information of China (English)

    LIU Handan; WANG Shigang; XU Wei

    2009-01-01

    Among the proposed techniques for delivering drugs to specific sites within the human body, magnetic targeting drug delivery surpasses due to its non-invasive character and its high targeting efficiency. Although there have been some analyses theoretically for magnetic drug targeting, very few researchers have addressed the hydrodynamic models of magnetic fluids in the blood vessel of human body. This paper presents a mathematical model to describe the hydrodynamics of ferrofluids as drug carriers flowing in a blood vessel under the applied magnetic field. A 3D flow field of magnetic particles in a blood vessel model is numerically simulated in order to further understand clinical application of magnetic targeting drug delivery. Simulation results show that magnetic nanoparticles can be enriched in a target region depending on the applied magnetic field intensity. Magnetic resonance imaging conftrms the enrichment of ferrofluids in a desired body tissue of Sprague-Dawley rats. The simulation results coincide with those animal experiments. Results of the analysis provide the important information and can suggest strategies for improving delivery in favor of the clinical application.

  16. Large-scale prediction of drug-target interactions using protein sequences and drug topological structures

    Energy Technology Data Exchange (ETDEWEB)

    Cao Dongsheng [Research Center of Modernization of Traditional Chinese Medicines, Central South University, Changsha 410083 (China); Liu Shao [Xiangya Hospital, Central South University, Changsha 410008 (China); Xu Qingsong [School of Mathematical Sciences and Computing Technology, Central South University, Changsha 410083 (China); Lu Hongmei; Huang Jianhua [Research Center of Modernization of Traditional Chinese Medicines, Central South University, Changsha 410083 (China); Hu Qiannan [Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071 (China); Liang Yizeng, E-mail: yizeng_liang@263.net [Research Center of Modernization of Traditional Chinese Medicines, Central South University, Changsha 410083 (China)

    2012-11-08

    Highlights: Black-Right-Pointing-Pointer Drug-target interactions are predicted using an extended SAR methodology. Black-Right-Pointing-Pointer A drug-target interaction is regarded as an event triggered by many factors. Black-Right-Pointing-Pointer Molecular fingerprint and CTD descriptors are used to represent drugs and proteins. Black-Right-Pointing-Pointer Our approach shows compatibility between the new scheme and current SAR methodology. - Abstract: The identification of interactions between drugs and target proteins plays a key role in the process of genomic drug discovery. It is both consuming and costly to determine drug-target interactions by experiments alone. Therefore, there is an urgent need to develop new in silico prediction approaches capable of identifying these potential drug-target interactions in a timely manner. In this article, we aim at extending current structure-activity relationship (SAR) methodology to fulfill such requirements. In some sense, a drug-target interaction can be regarded as an event or property triggered by many influence factors from drugs and target proteins. Thus, each interaction pair can be represented theoretically by using these factors which are based on the structural and physicochemical properties simultaneously from drugs and proteins. To realize this, drug molecules are encoded with MACCS substructure fingerings representing existence of certain functional groups or fragments; and proteins are encoded with some biochemical and physicochemical properties. Four classes of drug-target interaction networks in humans involving enzymes, ion channels, G-protein-coupled receptors (GPCRs) and nuclear receptors, are independently used for establishing predictive models with support vector machines (SVMs). The SVM models gave prediction accuracy of 90.31%, 88.91%, 84.68% and 83.74% for four datasets, respectively. In conclusion, the results demonstrate the ability of our proposed method to predict the drug-target

  17. Liposomes and nanotechnology in drug development: focus on ocular targets

    Directory of Open Access Journals (Sweden)

    Honda M

    2013-02-01

    Full Text Available Miki Honda,1 Tomohiro Asai,2 Naoto Oku,2 Yoshihiko Araki,3 Minoru Tanaka,1 Nobuyuki Ebihara11Department of Ophthalmology, Juntendo University Urayasu Hospital, Chiba, Japan; 2Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan; 3Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba, JapanAbstract: Poor drug delivery to lesions in patients' eyes is a major obstacle to the treatment of ocular diseases. The accessibility of these areas to drugs is highly restricted by the presence of barriers, including the corneal barrier, aqueous barrier, and the inner and outer blood–retinal barriers. In particular, the posterior segment is difficult to reach for drugs because of its structural peculiarities. This review discusses various barriers to drug delivery and provides comprehensive information for designing nanoparticle-mediated drug delivery systems for the treatment of ocular diseases. Nanoparticles can be designed to improve penetration, controlled release, and drug targeting. As highlighted in this review, the therapeutic efficacy of drugs in ocular diseases has been reported to be enhanced by the use of nanoparticles such as liposomes, micro/nanospheres, microemulsions, and dendrimers. Our recent data show that intravitreal injection of targeted liposomes encapsulating an angiogenesis inhibitor caused significantly greater suppression of choroidal neovascularization than did the injection of free drug. Recent progress in ocular drug delivery systems research has provided new insights into drug development, and the use of nanoparticles for drug delivery is thus a promising approach for advanced therapy of ocular diseases.Keywords: intravitreal injection, drug delivery system, age-related macular degeneration, APRPG-modified PEGylated liposome, DDS

  18. Computational design of nanoparticle drug delivery systems for selective targeting.

    Science.gov (United States)

    Duncan, Gregg A; Bevan, Michael A

    2015-10-01

    Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues.

  19. Targeted drug delivery by ultrasound-triggered margination of microbubbles

    CERN Document Server

    Guckenberger, Achim

    2016-01-01

    The ideal agent for targeted drug delivery should stay away from the biochemically active walls of the blood vessels during circulation. However, upon reaching its target it should attain a near-wall position. Though seemingly contradictory, we show that coated microbubbles (ultrasound contrast agents) possess precisely these two properties. Using numerical simulations we find that application of a localized ultrasound pulse at the target organ triggers their rapid migration from the vessel center toward the endothelial wall. This ultrasound-triggered margination is due to hydrodynamic interactions between the red blood cells and the oscillating bubbles. Importantly, we find that the effect is very robust, existing even if the duration in the stiff state is five times lower than the opposing time in the soft state. Our results might also explain why recent in-vivo studies found strongly enhanced drug uptake by co-administration of microbubbles with classical drug delivery agents.

  20. Nanobiotechnology-based drug delivery in brain targeting.

    Science.gov (United States)

    Dinda, Subas C; Pattnaik, Gurudutta

    2013-01-01

    Blood brain barrier (BBB) found to act as rate limiting factor in drug delivery to brain in combating the central nervous system (CNS) disorders. Such limiting physiological factors include the reticuloendothelial system and protein opsonization, which present across BBB, play major role in reducing the passage of drug. Several approaches employed to improve the drug delivery across the BBB. Nanoparticles (NP) are the solid colloidal particle ranges from 1 to 1000 nm in size utilized as career for drug delivery. At present NPs are found to play a significant advantage over the other methods of available drug delivery systems to deliver the drug across the BBB. Nanoparticles may be because of its size and functionalization characteristics able to penetrate and facilitate the drug delivery through the barrier. There are number of mechanisms and strategies found to be involved in this process, which are based on the type of nanomaterials used and its combination with therapeutic agents, such materials include liposomes, polymeric nanoparticles and non-viral vectors of nano-sizes for CNS gene therapy, etc. Nanotechnology is expected to reduce the need for invasive procedures for delivery of therapeutics to the CNS. Some devices such as implanted catheters and reservoirs however will still be needed to overcome the problems in effective drug delivery to the CNS. Nanomaterials are found to improve the safety and efficacy level of drug delivery devices in brain targeting. Nanoegineered devices are found to be delivering the drugs at cellular levels through nono-fluidic channels. Different drug delivery systems such as liposomes, microspheres, nanoparticles, nonogels and nonobiocapsules have been used to improve the bioavailability of the drug in the brain, but microchips and biodegradable polymeric nanoparticulate careers are found to be more effective therapeutically in treating brain tumor. The physiological approaches also utilized to improve the transcytosis capacity

  1. Targeted Liposomal Drug Delivery to Monocytes and Macrophages

    Directory of Open Access Journals (Sweden)

    Ciara Kelly

    2011-01-01

    Full Text Available As the role of monocytes and macrophages in a range of diseases is better understood, strategies to target these cell types are of growing importance both scientifically and therapeutically. As particulate carriers, liposomes naturally target cells of the mononuclear phagocytic system (MPS, particularly macrophages. Loading drugs into liposomes can therefore offer an efficient means of drug targeting to MPS cells. Physicochemical properties including size, charge and lipid composition can have a very significant effect on the efficiency with which liposomes target MPS cells. MPS cells express a range of receptors including scavenger receptors, integrins, mannose receptors and Fc-receptors that can be targeted by the addition of ligands to liposome surfaces. These ligands include peptides, antibodies and lectins and have the advantages of increasing target specificity and avoiding the need for cationic lipids to trigger intracellular delivery. The goal for targeting monocytes/macrophages using liposomes includes not only drug delivery but also potentially a role in cell ablation and cell activation for the treatment of conditions including cancer, atherosclerosis, HIV, and chronic inflammation.

  2. Targeting protein kinases in the malaria parasite: update of an antimalarial drug target.

    Science.gov (United States)

    Zhang, Veronica M; Chavchich, Marina; Waters, Norman C

    2012-01-01

    Millions of deaths each year are attributed to malaria worldwide. Transmitted through the bite of an Anopheles mosquito, infection and subsequent death from the Plasmodium species, most notably P. falciparum, can readily spread through a susceptible population. A malaria vaccine does not exist and resistance to virtually every antimalarial drug predicts that mortality and morbidity associated with this disease will increase. With only a few antimalarial drugs currently in the pipeline, new therapeutic options and novel chemotypes are desperately needed. Hit-to-Lead diversity may successfully provide novel inhibitory scaffolds when essential enzymes are targeted, for example, the plasmodial protein kinases. Throughout the entire life cycle of the malaria parasite, protein kinases are essential for growth and development. Ongoing efforts continue to characterize these kinases, while simultaneously pursuing them as antimalarial drug targets. A collection of structural data, inhibitory profiles and target validation has set the foundation and support for targeting the malarial kinome. Pursuing protein kinases as cancer drug targets has generated a wealth of information on the inhibitory strategies that can be useful for antimalarial drug discovery. In this review, progress on selected protein kinases is described. As the search for novel antimalarials continues, an understanding of the phosphor-regulatory pathways will not only validate protein kinase targets, but also will identify novel chemotypes to thwart malaria drug resistance. PMID:22242850

  3. Multifunctional Nanoparticles for Drug Delivery Applications Imaging, Targeting, and Delivery

    CERN Document Server

    Prud'homme, Robert

    2012-01-01

    This book clearly demonstrates the progression of nanoparticle therapeutics from basic research to applications. Unlike other books covering nanoparticles used in medical applications, Multifunctional Nanoparticles for Drug Delivery Applications presents the medical challenges that can be reduced or even overcome by recent advances in nanoscale drug delivery. Each chapter highlights recent progress in the design and engineering of select multifunctional nanoparticles with topics covering targeting, imaging, delivery, diagnostics, and therapy.

  4. Nanomechanics of Drug-target Interactions and Antibacterial Resistance Detection

    OpenAIRE

    Ndieyira, J. W.; Watari, M.; McKendry, R. A.

    2013-01-01

    The cantilever sensor, which acts as a transducer of reactions between model bacterial cell wall matrix immobilized on its surface and antibiotic drugs in solution, has shown considerable potential in biochemical sensing applications with unprecedented sensitivity and specificity(1-5). The drug-target interactions generate surface stress, causing the cantilever to bend, and the signal can be analyzed optically when it is illuminated by a laser. The change in surface stress measured with nano-...

  5. Identifying problematic drugs based on the characteristics of their targets

    Directory of Open Access Journals (Sweden)

    Tiago Jose eDa Silva Lopes

    2015-09-01

    Full Text Available Identifying promising compounds during the early stages of drug development is a major challenge for both academia and the pharmaceutical industry. The difficulties are even more pronounced when we consider multi-target pharmacology, where the compounds often target more than one protein, or multiple compounds are used together. Here, we address this problem by using machine learning and network analysis to process sequence and interaction data from human proteins to identify promising compounds. We used this strategy to identify properties that make certain proteins more likely to cause harmful effects when targeted; such proteins usually have domains commonly found throughout the human proteome. Additionally, since currently marketed drugs hit multiple targets simultaneously, we combined the information from individual proteins to devise a score that quantifies the likelihood of a compound being harmful to humans. This approach enabled us to distinguish between approved and problematic drugs with an accuracy of 60%¬–70%. Moreover, our approach can be applied as soon as candidate drugs are available, as demonstrated with predictions for more than 5000 experimental drugs. These resources are available at http://sourceforge.net/projects/psin/.

  6. New approaches to targeted drug delivery to tumour cells

    International Nuclear Information System (INIS)

    Basic approaches to the design of targeted drugs for the treatment of human malignant tumours have been considered. The stages of the development of these approaches have been described in detail and theoretically substantiated, and basic experimental results have been reported. Considerable attention is paid to the general characteristic of nanopharmacological drugs and to the description of mechanisms of cellular interactions with nanodrugs. The potentialities and limitations of application of nanodrugs for cancer therapy and treatment of other diseases have been considered. The use of nanodrugs conjugated with vector molecules seems to be the most promising trend of targeted therapy of malignant tumours. The bibliography includes 122 references

  7. New approaches to targeted drug delivery to tumour cells

    Science.gov (United States)

    Severin, E. S.

    2015-01-01

    Basic approaches to the design of targeted drugs for the treatment of human malignant tumours have been considered. The stages of the development of these approaches have been described in detail and theoretically substantiated, and basic experimental results have been reported. Considerable attention is paid to the general characteristic of nanopharmacological drugs and to the description of mechanisms of cellular interactions with nanodrugs. The potentialities and limitations of application of nanodrugs for cancer therapy and treatment of other diseases have been considered. The use of nanodrugs conjugated with vector molecules seems to be the most promising trend of targeted therapy of malignant tumours. The bibliography includes 122 references.

  8. A smart multifunctional drug delivery nanoplatform for targeting cancer cells

    Science.gov (United States)

    Hoop, M.; Mushtaq, F.; Hurter, C.; Chen, X.-Z.; Nelson, B. J.; Pané, S.

    2016-06-01

    Wirelessly guided magnetic nanomachines are promising vectors for targeted drug delivery, which have the potential to minimize the interaction between anticancer agents and healthy tissues. In this work, we propose a smart multifunctional drug delivery nanomachine for targeted drug delivery that incorporates a stimuli-responsive building block. The nanomachine consists of a magnetic nickel (Ni) nanotube that contains a pH-responsive chitosan hydrogel in its inner cavity. The chitosan inside the nanotube serves as a matrix that can selectively release drugs in acidic environments, such as the extracellular space of most tumors. Approximately a 2.5 times higher drug release from Ni nanotubes at pH = 6 is achieved compared to that at pH = 7.4. The outside of the Ni tube is coated with gold. A fluorescein isothiocyanate (FITC) labeled thiol-ssDNA, a biological marker, was conjugated on its surface by thiol-gold click chemistry, which enables traceability. The Ni nanotube allows the propulsion of the device by means of external magnetic fields. As the proposed nanoarchitecture integrates different functional building blocks, our drug delivery nanoplatform can be employed for carrying molecular drug conjugates and for performing targeted combinatorial therapies, which can provide an alternative and supplementary solution to current drug delivery technologies.Wirelessly guided magnetic nanomachines are promising vectors for targeted drug delivery, which have the potential to minimize the interaction between anticancer agents and healthy tissues. In this work, we propose a smart multifunctional drug delivery nanomachine for targeted drug delivery that incorporates a stimuli-responsive building block. The nanomachine consists of a magnetic nickel (Ni) nanotube that contains a pH-responsive chitosan hydrogel in its inner cavity. The chitosan inside the nanotube serves as a matrix that can selectively release drugs in acidic environments, such as the extracellular space of

  9. Polymeric nanoparticles for drug delivery and targeting: A comprehensive review

    Directory of Open Access Journals (Sweden)

    Natarajan Jawahar

    2012-01-01

    Full Text Available In the recent years, many modern technologies have been established in the pharmaceutical research and development area. The field of nanotechnology has been revolutionary as substantial and technical, and scientific growth, in basic sciences plus manipulation by physical or chemical process of individual atoms and molecules have widened its horizon. Polymeric nanoparticles with a size in the nanometer range protect drugs against in vitro and in vivo degradation; it releases the drug in a controlled manner and also offers the possibility of drug targeting. The use of polymeric drug nanoparticles is a universal approach to increase the therapeutic performance of poorly soluble drugs in any route of administration. The present review discusses the physico-chemical properties of polymeric nanoparticles, production methods, routes of administration and potential therapeutic applications.

  10. Novel targeted bladder drug-delivery systems: a review

    Directory of Open Access Journals (Sweden)

    Zacchè MM

    2015-11-01

    Full Text Available Martino Maria Zacchè, Sushma Srikrishna, Linda Cardozo Department of Urogynaecology, King's College Hospital, London, UK Abstract: The objective of pharmaceutics is the development of drugs with increased efficacy and reduced side effects. Prolonged exposure of the diseased tissue to the drug is of crucial importance. Drug-delivery systems (DDSs have been introduced to control rate, time, and place of release. Drugs can easily reach the bladder through a catheter, while systemically administered agents may undergo extensive metabolism. Continuous urine filling and subsequent washout hinder intravesical drug delivery (IDD. Moreover, the low permeability of the urothelium, also described as the bladder permeability barrier, poses a major challenge in the development of the IDD. DDSs increase bioavailability of drugs, therefore improving therapeutic effect and patient compliance. This review focuses on novel DDSs to treat bladder conditions such as overactive bladder, interstitial cystitis, bladder cancer, and recurrent urinary tract infections. The rationale and strategies for both systemic and local delivery methods are discussed, with emphasis on new formulations of well-known drugs (oxybutynin, nanocarriers, polymeric hydrogels, intravesical devices, encapsulated DDSs, and gene therapy. We give an overview of current and future prospects of DDSs for bladder disorders, including nanotechnology and gene therapy. Keywords: drug targeting, drug-delivery system, bladder disorders

  11. Targeting Antibacterial Agents by Using Drug-Carrying Filamentous Bacteriophages

    OpenAIRE

    Yacoby, Iftach; Shamis, Marina; Bar, Hagit; Shabat, Doron; Benhar, Itai

    2006-01-01

    Bacteriophages have been used for more than a century for (unconventional) therapy of bacterial infections, for half a century as tools in genetic research, for 2 decades as tools for discovery of specific target-binding proteins, and for nearly a decade as tools for vaccination or as gene delivery vehicles. Here we present a novel application of filamentous bacteriophages (phages) as targeted drug carriers for the eradication of (pathogenic) bacteria. The phages are genetically modified to d...

  12. Prediction of drug-target interactions and drug repositioning via network-based inference.

    Directory of Open Access Journals (Sweden)

    Feixiong Cheng

    Full Text Available Drug-target interaction (DTI is the basis of drug discovery and design. It is time consuming and costly to determine DTI experimentally. Hence, it is necessary to develop computational methods for the prediction of potential DTI. Based on complex network theory, three supervised inference methods were developed here to predict DTI and used for drug repositioning, namely drug-based similarity inference (DBSI, target-based similarity inference (TBSI and network-based inference (NBI. Among them, NBI performed best on four benchmark data sets. Then a drug-target network was created with NBI based on 12,483 FDA-approved and experimental drug-target binary links, and some new DTIs were further predicted. In vitro assays confirmed that five old drugs, namely montelukast, diclofenac, simvastatin, ketoconazole, and itraconazole, showed polypharmacological features on estrogen receptors or dipeptidyl peptidase-IV with half maximal inhibitory or effective concentration ranged from 0.2 to 10 µM. Moreover, simvastatin and ketoconazole showed potent antiproliferative activities on human MDA-MB-231 breast cancer cell line in MTT assays. The results indicated that these methods could be powerful tools in prediction of DTIs and drug repositioning.

  13. [Development of drug delivery systems for targeting to macrophages].

    Science.gov (United States)

    Chono, Sumio

    2007-09-01

    Drug delivery systems (DDS) using liposomes as drug carriers for targeting to macrophages have been developed for the treatment of diseases that macrophages are related to their progress. Initially, DDS for the treatment of atherosclerosis are described. The influence of particle size on the drug delivery to atherosclerotic lesions that macrophages are richly present and antiatherosclerotic effects following intravenous administration of liposomes containing dexamethasone (DXM-liposomes) was investigated in atherogenic mice. Both the drug delivery efficacy of DXM-liposomes (particle size, 200 nm) to atherosclerotic lesions and their antiatherosclerotic effects were greater than those of 70 and 500 nm. These results indicate that there is an optimal particle size for drug delivery to atherosclerotic lesions. DDS for the treatment of respiratory infections are then described. The influence of particle size and surface mannosylation on the drug delivery to alveolar macrophages (AMs) and antibacterial effects following pulmonary administration of liposomes containing ciprofloxacin (CPFX-liposomes) was investigated in rats. The drug delivery efficacy of CPFX-liposomes to AMs was particle size-dependent over the range 100-1000 nm and then became constant at over 1000 nm. These results indicate that the most effective size is 1000 nm. Both the drug delivery efficacy of mannosylated CPFX-liposomes (particle size, 1000 nm) to AMs and their antibacterial effects were significantly greater than those of unmodified CPFX-liposomes. These results indicate that the surface mannosylation is useful method for drug delivery to AMs. This review provides useful information to help in the development of novel pharmaceutical formulations aimed at drug targeting to macrophages.

  14. Injectable nanomaterials for drug delivery: carriers, targeting moieties, and therapeutics.

    Science.gov (United States)

    Webster, David M; Sundaram, Padma; Byrne, Mark E

    2013-05-01

    Therapeutics such as nucleic acids, proteins/peptides, vaccines, anti-cancer, and other drugs have disadvantages of low bio-availability, rapid clearance, and high toxicity. Thus, there is a significant need for the development of efficient delivery methods and carriers. Injectable nanocarriers have received much attention due to their vast range of structures and ability to contain multiple functional groups, both within the bulk material and on the surface of the particles. Nanocarriers may be tailored to control drug release and/or increase selective cell targeting, cellular uptake, drug solubility, and circulation time, all of which lead to a more efficacious delivery and action of therapeutics. The focus of this review is injectable, targeted nanoparticle drug delivery carriers highlighting the diversity of nanoparticle materials and structures as well as highlighting current therapeutics and targeting moieties. Structures and materials discussed include liposomes, polymersomes, dendrimers, cyclodextrin-containing polymers (CDPs), carbon nanotubes (CNTs), and gold nanoparticles. Additionally, current clinical trial information and details such as trial phase, treatment, active drug, carrier sponsor, and clinical trial identifier for different materials and structures are presented and discussed.

  15. Spherons as a drug target in Alzheimer's disease.

    Science.gov (United States)

    Averback, P

    1998-10-01

    Spherons are unique brain entities that are causally linked to the amyloid plaques (SPs [senile plaques]) of Alzheimer's disease (AD). SPs are the quantitatively major tissue abnormality of AD. Spherons increase in size (but not in number) gradually throughout life until they reach a size range where they burst and form SPs. Drugs targeted at attenuating the process of spheron transformation into SPs are a logical approach to AD therapy. There are 20 criteria of validity for an SP causal entity that are satisfied by spherons-and no more than a few of these 20 criteria are satisfied by any other known hypothesis. These criteria of validity are reviewed, in addition to common difficulties in understanding spheron theory and a number of common-sense considerations in AD therapeutic research. Spheron-based drug therapy in AD potentially can retard the process of spheron bursting and subsequent plaque formation by: 1) blocking the formation of SPs; 2) reducing the size of SPs; 3) delaying spheron breakdown; and 4) retarding spheron growth. Isolated spherons from human brain are intact human drug targets and can be used as human in vitro or in vivo screening targets. The paramount importance of spherons as a target for drug therapy in AD is emphasized by considering that regardless of any other type of real or potential therapy, there still already exists in every middle-aged adult a full population of spherons in the brain, filled with more than enough amyloid to bring about full-blown AD.

  16. In silico search of DNA drugs targeting oncogenes.

    Science.gov (United States)

    Papadakis, George; Gizeli, Electra

    2012-01-01

    Triplex forming oligonucleotides (TFOs) represent a class of drug candidates for antigene therapy. Based on strict criteria, we investigated the potential of 25 known oncogenes to be regulated by TFOs in the mRNA synthesis level and we report specific target sequences found in seven of these genes. PMID:23221090

  17. Mitochondrial chaperones may be targets for anti-cancer drugs

    Science.gov (United States)

    Scientists at NCI have found that a mitochondrial chaperone protein, TRAP1, may act indirectly as a tumor suppressor as well as a novel target for developing anti-cancer drugs. Chaperone proteins, such as TRAP1, help other proteins adapt to stress, but sc

  18. Nanofabricated biomimetic structures for smart targeting and drug delivery

    NARCIS (Netherlands)

    Dudia, Alma; Kanger, Johannes S.; Subramaniam, Vinod

    2005-01-01

    We present a new approach to hybrid artificial cells (AC) designed for specific targeting and active drug delivery by combining an impermeable non-biological scaffold with an artificial bilayer lipid membrane (BLM) that supports the functioning bio-molecules required to provide AC functionality. We

  19. Current and future drug targets in weight management

    NARCIS (Netherlands)

    Witkamp, R.F.

    2011-01-01

    Obesity will continue to be one of the leading causes of chronic disease unless the ongoing rise in the prevalence of this condition is reversed. Accumulating morbidity figures and a shortage of effective drugs have generated substantial research activity with several molecular targets being investi

  20. Leishmaniasis:Current status of available drugs and new potential drug targets

    Institute of Scientific and Technical Information of China (English)

    Nisha Singh; Manish Kumar; Rakesh Kumar Singh

    2012-01-01

    The control ofLeishmania infection relies primarily on chemotherapy till date. Resistance to pentavalent antimonials, which have been the recommended drugs to treat cutaneous and visceral leishmaniasis, is now widespread in Indian subcontinents. New drug formulations like amphotericinB, its lipid formulations, and miltefosine have shown great efficacy to treat leishmaniasis but their high cost and therapeutic complications limit their usefulness. In addition, irregular and inappropriate uses of these second line drugs in endemic regions like state of Bihar, India threaten resistance development in the parasite. In context to the limited drug options and unavailability of either preventive or prophylactic candidates, there is a pressing need to develop true antileishmanial drugs to reduce the disease burden of this debilitating endemic disease. Notwithstanding significant progress of leishmanial research during last few decades, identification and characterization of novel drugs and drug targets are far from satisfactory. This review will initially describe current drug regimens and later will provide an overview on few important biochemical and enzymatic machineries that could be utilized as putative drug targets for generation of true antileishmanial drugs.

  1. Wzy-dependent bacterial capsules as potential drug targets.

    Science.gov (United States)

    Ericsson, Daniel J; Standish, Alistair; Kobe, Bostjan; Morona, Renato

    2012-10-01

    The bacterial capsule is a recognized virulence factor in pathogenic bacteria. It likely works as an antiphagocytic barrier by minimizing complement deposition on the bacterial surface. With the continual rise of bacterial pathogens resistant to multiple antibiotics, there is an increasing need for novel drugs. In the Wzy-dependent pathway, the biosynthesis of capsular polysaccharide (CPS) is regulated by a phosphoregulatory system, whose main components consist of bacterial-tyrosine kinases (BY-kinases) and their cognate phosphatases. The ability to regulate capsule biosynthesis has been shown to be vital for pathogenicity, because different stages of infection require a shift in capsule thickness, making the phosphoregulatory proteins suitable as drug targets. Here, we review the role of regulatory proteins focusing on Streptococcus pneumoniae, Staphylococcus aureus, and Escherichia coli and discuss their suitability as targets in structure-based drug design.

  2. Functional and mechanistic analysis of telomerase: An antitumor drug target.

    Science.gov (United States)

    Chen, Yinnan; Zhang, Yanmin

    2016-07-01

    The current research on anticancer drugs focuses on exploiting particular traits or hallmarks unique to cancer cells. Telomerase, a special reverse transcriptase, has been recognized as a common factor in most tumor cells, and in turn a distinctive characteristic with respect to non-malignant cells. This feature has made telomerase a preferred target for anticancer drug development and cancer therapy. This review aims to analyze the pharmacological function and mechanism and role of telomerase in oncogenesis; to provide fundamental knowledge for research on the structure, function, and working mechanism of telomerase; to expound the role that telomerase plays in the initiation and development of tumor and its relationship with tumor cell growth, proliferation, apoptosis, and related pathway molecules; and to display potential targets of antitumor drug for inhibiting the expression, reconstitution, and trafficking of the enzyme. We therefore summarize recent advances in potential telomerase inhibitors for antitumor including natural products, synthetic small molecules, peptides and proteins, which indicate that optimizing the delivery method and drug combination could be of help in a combinatorial drug treatment for tumor. More extensive understanding of the structure, biogenesis, and mechanism of telomerase will provide invaluable information for increasing the efficiency of rational antitumor drug design. PMID:27118336

  3. The tuberculosis drug discovery and development pipeline and emerging drug targets.

    Science.gov (United States)

    Mdluli, Khisimuzi; Kaneko, Takushi; Upton, Anna

    2015-06-01

    The recent accelerated approval for use in extensively drug-resistant and multidrug-resistant-tuberculosis (MDR-TB) of two first-in-class TB drugs, bedaquiline and delamanid, has reinvigorated the TB drug discovery and development field. However, although several promising clinical development programs are ongoing to evaluate new TB drugs and regimens, the number of novel series represented is few. The global early-development pipeline is also woefully thin. To have a chance of achieving the goal of better, shorter, safer TB drug regimens with utility against drug-sensitive and drug-resistant disease, a robust and diverse global TB drug discovery pipeline is key, including innovative approaches that make use of recently acquired knowledge on the biology of TB. Fortunately, drug discovery for TB has resurged in recent years, generating compounds with varying potential for progression into developable leads. In parallel, advances have been made in understanding TB pathogenesis. It is now possible to apply the lessons learned from recent TB hit generation efforts and newly validated TB drug targets to generate the next wave of TB drug leads. Use of currently underexploited sources of chemical matter and lead-optimization strategies may also improve the efficiency of future TB drug discovery. Novel TB drug regimens with shorter treatment durations must target all subpopulations of Mycobacterium tuberculosis existing in an infection, including those responsible for the protracted TB treatment duration. This review summarizes the current TB drug development pipeline and proposes strategies for generating improved hits and leads in the discovery phase that could help achieve this goal. PMID:25635061

  4. Liposomes and nanotechnology in drug development: focus on neurological targets

    Directory of Open Access Journals (Sweden)

    Ramos-Cabrer P

    2013-03-01

    Full Text Available Pedro Ramos-Cabrer, Francisco Campos Clinical Neurosciences Research Laboratory, Department of Neurology, Hospital Clínico Universitario de Santiago, University of Santiago de Compostela, Health Research Institute of Santiago, Santiago de Compostela, Spain Abstract: Neurological diseases represent a medical, social, and economic problem of paramount importance in developed countries. Although their etiology is generally known, developing therapeutic interventions for the central nervous system is challenging due to the impermeability of the blood–brain barrier. Thus, the fight against neurological diseases usually struggles "at the gates" of the brain. Flooding the bloodstream with drugs, where only a minor fraction reaches its target therapeutic site, is an inefficient, expensive, and dangerous procedure, because of the risk of side effects at nontargeted sites. Currently, advances in the field of nanotechnology have enabled development of a generation of multifunctional molecular platforms that are capable of transporting drugs across the blood–brain barrier, targeting specific cell types or functional states within the brain, releasing drugs in a controlled manner, and enabling visualization of processes in vivo using conventional imaging systems. The marriage between drug delivery and molecular imaging disciplines has resulted in a relatively new discipline, known as theranostics, which represents the basis of the concept of personalized medicine. In this study, we review the concepts of the blood–brain barrier and the strategies used to traverse/bypass it, the role of nanotechnology in theranostics, the wide range of nanoparticles (with emphasis on liposomes that can be used as stealth drug carriers, imaging probes and targeting devices for the treatment of neurological diseases, and the targets and targeting strategies envisaged in the treatment of different types of brain pathology. Keywords: nanotechnology, theranostics, blood

  5. Pericyte-targeting drug delivery and tissue engineering

    Science.gov (United States)

    Kang, Eunah; Shin, Jong Wook

    2016-01-01

    Pericytes are contractile mural cells that wrap around the endothelial cells of capillaries and venules. Depending on the triggers by cellular signals, pericytes have specific functionality in tumor microenvironments, properties of potent stem cells, and plasticity in cellular pathology. These features of pericytes can be activated for the promotion or reduction of angiogenesis. Frontier studies have exploited pericyte-targeting drug delivery, using pericyte-specific peptides, small molecules, and DNA in tumor therapy. Moreover, the communication between pericytes and endothelial cells has been applied to the induction of vessel neoformation in tissue engineering. Pericytes may prove to be a novel target for tumor therapy and tissue engineering. The present paper specifically reviews pericyte-specific drug delivery and tissue engineering, allowing insight into the emerging research targeting pericytes. PMID:27313454

  6. Cancer targeted therapeutics: From molecules to drug delivery vehicles.

    Science.gov (United States)

    Liu, Daxing; Auguste, Debra T

    2015-12-10

    The pitfall of all chemotherapeutics lies in drug resistance and the severe side effects experienced by patients. One way to reduce the off-target effects of chemotherapy on healthy tissues is to alter the biodistribution of drug. This can be achieved in two ways: Passive targeting utilizes shape, size, and surface chemistry to increase particle circulation and tumor accumulation. Active targeting employs either chemical moieties (e.g. peptides, sugars, aptamers, antibodies) to selectively bind to cell membranes or responsive elements (e.g. ultrasound, magnetism, light) to deliver its cargo within a local region. This article will focus on the systemic administration of anti-cancer agents and their ability to home to tumors and, if relevant, distant metastatic sites.

  7. Computational design of nanoparticle drug delivery systems for selective targeting

    Science.gov (United States)

    Duncan, Gregg A.; Bevan, Michael A.

    2015-09-01

    Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues.Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting

  8. Multiple Targets for Drug-Induced Mitochondrial Toxicity.

    Science.gov (United States)

    Wallace, Kendall B

    2015-01-01

    Mitochondrial toxicity is rapidly gaining the interest of researchers and practitioners as a prominent liability in drug discovery and development, accounting for a growing proportion of preclinical drug attrition and post-market withdrawals or black box warnings by the U.S. FDA. To date, the focus of registries of drugs that elicit mitochondrial toxicity has been largely restricted to those that either inhibit the mitochondrial electron transport chain (ETC) or uncouple mitochondrial oxidative phosphorylation. Less appreciated are the toxicities that are secondary to the drug affecting either the molecular regulation, assembly or incorporation of the ETC into the inner mitochondrial membrane or those that limit substrate availability. The current article describes the complexities of molecular events and biochemical pathways required to sustain mitochondrial fidelity and substrate homeostasis with examples of drugs that interfere which the various pathways. The principal objective of this review is to shed light on the broader scope of drug-induced mitochondrial toxicities and how these secondary targets may account for a large portion of drug failures. PMID:25973981

  9. Mechanistic models enable the rational use of in vitro drug-target binding kinetics for better drug effects in patients.

    NARCIS (Netherlands)

    Witte, W.E.; Wong, Y.C.; Nederpelt, I.; Heitman, L.H.; Danhof, M.; Graaf, van der P.H.; Gilissen, R.A.; de, Lange E.C.

    2016-01-01

    INTRODUCTION Drug-target binding kinetics are major determinants of the time course of drug action for several drugs, as clearly described for the irreversible binders omeprazole and aspirin. This supports the increasing interest to incorporate newly developed high-throughput assays for drug-target

  10. A review on target drug delivery: magnetic microspheres

    Directory of Open Access Journals (Sweden)

    Amit Chandna

    2013-01-01

    Magnetic microsphere is newer approach in pharmaceutical field. Magnetic microspheres as an alternative to traditional radiation methods which use highly penetrating radiation that is absorbed throughout the body. Its use is limited by toxicity and side effects. The aim of the specific targeting is to enhance the efficiency of drug delivery & at the same time to reduce the toxicity & side effects. This kind of delivery system is very much important which localises the drug to the disease site. In this larger amount of freely circulating drug can be replaced by smaller amount of magnetically targeted drug. Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microspheres are chitosan, dextran etc. magnetic microspheres can be prepared from a variety of carrier material. One of the most utilized is serum albumin from human or other appropriate species. Drug release from albumin microspheres can be sustained or controlled by various stabilization procedures generally involving heat or chemical cross-linking of the protein carrier matrix.

  11. Genetic Approaches To Identifying Novel Osteoporosis Drug Targets.

    Science.gov (United States)

    Brommage, Robert

    2015-10-01

    During the past two decades effective drugs for treating osteoporosis have been developed, including anti-resorptives inhibiting bone resorption (estrogens, the SERM raloxifene, four bisphosphonates, RANKL inhibitor denosumab) and the anabolic bone forming daily injectable peptide teriparatide. Two potential drugs (odanacatib and romosozumab) are in late stage clinical development. The most pressing unmet need is for orally active anabolic drugs. This review describes the basic biological studies involved in developing these drugs, including the animal models employed for osteoporosis drug development. The genomics revolution continues to identify potential novel osteoporosis drug targets. Studies include human GWAS studies and identification of mutant genes in subjects having abnormal bone mass, mouse QTL and gene knockouts, and gene expression studies. Multiple lines of evidence indicate that Wnt signaling plays a major role in regulating bone formation and continued study of this complex pathway is likely to lead to key discoveries. In addition to the classic Wnt signaling targets DKK1 and sclerostin, LRP4, LRP5/LRP6, SFRP4, WNT16, and NOTUM can potentially be targeted to modulate Wnt signaling. Next-generation whole genome and exome sequencing, RNA-sequencing and CRISPR/CAS9 gene editing are new experimental techniques contributing to understanding the genome. The International Knockout Mouse Consortium efforts to knockout and phenotype all mouse genes are poised to accelerate. Accumulating knowledge will focus attention on readily accessible databases (Big Data). Efforts are underway by the International Bone and Mineral Society to develop an annotated Skeletome database providing information on all genes directly influencing bone mass, architecture, mineralization or strength. PMID:25833316

  12. Combinatorial approaches for the identification of brain drug delivery targets.

    Science.gov (United States)

    Stutz, Charles C; Zhang, Xiaobin; Shusta, Eric V

    2014-01-01

    The blood-brain barrier (BBB) represents a large obstacle for the treatment of central nervous system diseases. Targeting endogenous nutrient transporters that transcytose the BBB is one promising approach to selectively and noninvasively deliver a drug payload to the brain. The main limitations of the currently employed transcytosing receptors are their ubiquitous expression in the peripheral vasculature and the inherent low levels of transcytosis mediated by such systems. In this review, approaches designed to increase the repertoire of transcytosing receptors which can be targeted for the purpose of drug delivery are discussed. In particular, combinatorial protein libraries can be screened on BBB cells in vitro or in vivo to isolate targeting peptides or antibodies that can trigger transcytosis. Once these targeting reagents are discovered, the cognate BBB transcytosis system can be identified using techniques such as expression cloning or immunoprecipitation coupled with mass spectrometry. Continued technological advances in BBB genomics and proteomics, membrane protein manipulation, and in vitro BBB technology promise to further advance the capability to identify and optimize peptides and antibodies capable of mediating drug transport across the BBB.

  13. Pericyte-targeting drug delivery and tissue engineering

    Directory of Open Access Journals (Sweden)

    Kang E

    2016-05-01

    Full Text Available Eunah Kang,1 Jong Wook Shin2 1School of Chemical Engineering and Material Science, 2Division of Allergic and Pulmonary Medicine, Department of Internal Medicine, College of Medicine, Chung-Ang University, Dongjak-Gu, Seoul, South Korea Abstract: Pericytes are contractile mural cells that wrap around the endothelial cells of capillaries and venules. Depending on the triggers by cellular signals, pericytes have specific functionality in tumor microenvironments, properties of potent stem cells, and plasticity in cellular pathology. These features of pericytes can be activated for the promotion or reduction of angiogenesis. Frontier studies have exploited pericyte-targeting drug delivery, using pericyte-specific peptides, small molecules, and DNA in tumor therapy. Moreover, the communication between pericytes and endothelial cells has been applied to the induction of vessel neoformation in tissue engineering. Pericytes may prove to be a novel target for tumor therapy and tissue engineering. The present paper specifically reviews pericyte-specific drug delivery and tissue engineering, allowing insight into the emerging research targeting pericytes. Keywords: pericytes, pericyte-targeting drug delivery, tissue engineering, platelet-derived growth factor, angiogenesis, vascular remodeling

  14. Drugs that target pathogen public goods are robust against evolved drug resistance.

    Science.gov (United States)

    Pepper, John W

    2012-11-01

    Pathogen drug resistance is a central problem in medicine and public health. It arises through somatic evolution, by mutation and selection among pathogen cells within a host. Here, we examine the hypothesis that evolution of drug resistance could be reduced by developing drugs that target the secreted metabolites produced by pathogen cells instead of directly targeting the cells themselves. Using an agent-based computational model of an evolving population of pathogen cells, we test this hypothesis and find support for it. We also use our model to explain this effect within the framework of standard evolutionary theory. We find that in our model, the drugs most robust against evolved drug resistance are those that target the most widely shared external products, or 'public goods', of pathogen cells. We also show that these drugs exert a weak selective pressure for resistance because they create only a weak correlation between drug resistance and cell fitness. The same principles apply to design of vaccines that are robust against vaccine escape. Because our theoretical results have crucial practical implications, they should be tested by empirical experiments.

  15. NIOSOMES: A ROLE IN TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Soumya Singh

    2013-02-01

    Full Text Available Niosomes are non-ionic surfactant vesicles inclosing an aqueous phase and a wide range of molecules could be encapsulated within aqueous spaces of lipid membrane vesicles. They are microscopic lamellar structures formed on the admixture of a non-ionic surfactant, cholesterol and phosphate with subsequent hydration in aqueous media. Niosomes belongs to novel drug delivery system which offers a large number of advantages over other conventional and vesicular delivery systems. Namely they are the targeted drug delivery system which showing reduction of dose, stability and compatibility of non-ionic surfactants, easy modification, delayed clearance, suitability for a wide range of Active Pharmaceutical Agents.

  16. An efficient targeted drug delivery through apotransferrin loaded nanoparticles.

    Directory of Open Access Journals (Sweden)

    Athuluri Divakar Sai Krishna

    Full Text Available BACKGROUND: Cancerous state is a highly stimulated environment of metabolically active cells. The cells under these conditions over express selective receptors for assimilation of factors essential for growth and transformation. Such receptors would serve as potential targets for the specific ligand mediated transport of pharmaceutically active molecules. The present study demonstrates the specificity and efficacy of protein nanoparticle of apotransferrin for targeted delivery of doxorubicin. METHODOLOGY/PRINCIPAL FINDINGS: Apotransferrin nanoparticles were developed by sol-oil chemistry. A comparative analysis of efficiency of drug delivery in conjugated and non-conjugated forms of doxorubicin to apotransferrin nanoparticle is presented. The spherical shaped apotransferrin nanoparticles (nano have diameters of 25-50 etam, which increase to 60-80 etam upon direct loading of drug (direct-nano, and showed further increase in dimension (75-95 etam in conjugated nanoparticles (conj-nano. The competitive experiments with the transferrin receptor specific antibody showed the entry of both conj-nano and direct-nano into the cells through transferrin receptor mediated endocytosis. Results of various studies conducted clearly establish the superiority of the direct-nano over conj-nano viz. (a localization studies showed complete release of drug very early, even as early as 30 min after treatment, with the drug localizing in the target organelle (nucleus (b pharmacokinetic studies showed enhanced drug concentrations, in circulation with sustainable half-life (c the studies also demonstrated efficient drug delivery, and an enhanced inhibition of proliferation in cancer cells. Tissue distribution analysis showed intravenous administration of direct nano lead to higher drug localization in liver, and blood as compared to relatively lesser localization in heart, kidney and spleen. Experiments using rat cancer model confirmed the efficacy of the formulation in

  17. Core as a Novel Viral Target for Hepatitis C Drugs

    OpenAIRE

    Guillaume Mousseau; Snyder, John K.; Arthur Donny Strosberg; Virginia Takahashi; Smitha Kota

    2010-01-01

    Hepatitis C virus (HCV) infects over 130 million people worldwide and is a major cause of liver disease. No vaccine is available. Novel specific drugs for HCV are urgently required, since the standard-of-care treatment of pegylated interferon combined with ribavirin is poorly tolerated and cures less than half of the treated patients. Promising, effective direct-acting drugs currently in the clinic have been described for three of the ten potential HCV target proteins: NS3/NS4A protease, NS5B...

  18. Bacterial Transcription as a Target for Antibacterial Drug Development.

    Science.gov (United States)

    Ma, Cong; Yang, Xiao; Lewis, Peter J

    2016-03-01

    Transcription, the first step of gene expression, is carried out by the enzyme RNA polymerase (RNAP) and is regulated through interaction with a series of protein transcription factors. RNAP and its associated transcription factors are highly conserved across the bacterial domain and represent excellent targets for broad-spectrum antibacterial agent discovery. Despite the numerous antibiotics on the market, there are only two series currently approved that target transcription. The determination of the three-dimensional structures of RNAP and transcription complexes at high resolution over the last 15 years has led to renewed interest in targeting this essential process for antibiotic development by utilizing rational structure-based approaches. In this review, we describe the inhibition of the bacterial transcription process with respect to structural studies of RNAP, highlight recent progress toward the discovery of novel transcription inhibitors, and suggest additional potential antibacterial targets for rational drug design.

  19. Functional liposomes in the cancer-targeted drug delivery.

    Science.gov (United States)

    Tila, Dena; Ghasemi, Saeed; Yazdani-Arazi, Seyedeh Narjes; Ghanbarzadeh, Saeed

    2015-07-01

    Cancer is considered as one of the most severe health problems and is currently the third most common cause of death in the world after heart and infectious diseases. Novel therapies are constantly being discovered, developed and trialed. Many of the current anticancer agents exhibit non-ideal pharmaceutical and pharmacological properties and are distributed non-specifically throughout the body. This results in death of the both normal healthy and malignant cells and substantially leads to accruing a variety of serious toxic side effects. Therefore, the efficient systemic therapy of cancer is almost impossible due to harmful side effects of anticancer agents to the healthy organs and tissues. Furthermore, several problems such as low bioavailability of the drugs, low drug concentrations at the site of action, lack of drug specificity and drug-resistance also cause many restrictions on clinical applications of these drugs in the tumor therapy. Different types of the liposomal formulations have been used in medicine due to their distinctive advantages associated with their structural flexibility in the encapsulation of various agents with different physicochemical properties. They can also mediate delivery of the cargo to the appropriate cell type and subcellular compartment, reducing the effective dosage and possible side effects which are related to high systemic concentrations. Therefore, these novel systems were found very promising and encouraging dosage forms for the treatment of different types of cancer by increasing efficiency and reducing the systemic toxicity due to the specific drug delivery and targeting. PMID:25823898

  20. Approaches of targeting Rho GTPases in cancer drug discovery

    Science.gov (United States)

    Lin, Yuan; Zheng, Yi

    2016-01-01

    Introduction Rho GTPases are master regulators of actomyosin structure and dynamics and play pivotal roles in a variety of cellular processes including cell morphology, gene transcription, cell cycle progression and cell adhesion. Because aberrant Rho GTPase signaling activities are widely associated with human cancer, key components of Rho GTPase signaling pathways have attracted increasing interest as potential therapeutic targets. Similar to Ras, Rho GTPases themselves were, until recently, deemed “undruggable” because of structure-function considerations. Several approaches to interfere with Rho GTPase signaling have been explored and show promise as new ways for tackling cancer cells. Areas covered This review focuses on the recent progress in targeting the signaling activities of three prototypical Rho GTPases, i.e. RhoA, Rac1, and Cdc42. The authors describe the involvement of these Rho GTPases, their key regulators and effectors in cancer. Furthermore, the authors discuss the current approaches for rationally targeting aberrant Rho GTPases along their signaling cascades, upstream and downstream of Rho GTPases and posttranslational modifications at a molecular level. Expert opinion To date, while no clinically effective drugs targeting Rho GTPase signaling for cancer treatment are available, tool compounds and lead drugs that pharmacologically inhibit Rho GTPase pathways have shown promise. Small molecule inhibitors targeting Rho GTPase signaling may add new treatment options for future precision cancer therapy, particularly in combination with other anti-cancer agents. PMID:26087073

  1. USE OF LIPOSOMES AND NANOPARTICLES FOR BRAIN DRUG TARGETING

    Directory of Open Access Journals (Sweden)

    Goutam Pal

    2012-08-01

    Full Text Available The Blood Brain Barrier (BBB poses a obstacle for a drugs, including antineoplastic agent, antibiotics, neuropeptides, CNS active agents, to be delivered to the brain for therapeutic reasons. The use of formulation dependent strategy such as the use of heterogenous pharmaceutical systems for its effective targeting to the brain is being explored recently. Liposomes and Nanoparticles are good possibilities to achieve the goal. Chemically modified liposomes and nanoparticles are tried in recent times to act as brain targeting aids, and this article tries to explain the possibilities and problems behind such an endeavor.KEY WORDS:

  2. Drug targets for lymphatic filariasis: A bioinformatics approach

    Directory of Open Access Journals (Sweden)

    Om Prakash Sharma

    2013-08-01

    Full Text Available This review article discusses the current scenario of the national and international burden due to lymphatic filariasis (LF and describes the active elimination programmes for LF and their achievements to eradicate this most debilitating disease from the earth. Since, bioinformatics is a rapidly growing field of biological study, and it has an increasingly significant role in various fields of biology. We have reviewed its leading involvement in the filarial research using different approaches of bioinformatics and have summarized available existing drugs and their targets to re-examine and to keep away from the resisting conditions. Moreover, some of the novel drug targets have been assembled for further study to design fresh and better pharmacological therapeutics. Various bioinformatics-based web resources, and databases have been discussed, which may enrich the filarial research.

  3. Smooth muscle-specific drug targets for next generation Drug-eluting stent

    OpenAIRE

    Tang, Rui; Chen, Shiyou

    2013-01-01

    The occurrence of stent thrombosis is one of the major obstacles limiting the long-term clinical efficacy of percutaneous coronary intervention. The anti-smooth muscle proliferation drugs coated on drug-eluting stents (DES) often indistinguishably block re-endothelialization, an essential step toward successful vascular repair, due to their non-specific effect on endothelial cells (EC). Therefore, identification of therapeutic targets that differentially regulate vascular smooth muscle cell (...

  4. Metaphors in Nanomedicine: The Case of Targeted Drug Delivery

    OpenAIRE

    Bensaude Vincent, Bernadette; Loeve, Sacha

    2014-01-01

    The promises of nanotechnology have been framed by a variety of metaphors, that not only channel the attention of the public, orient the questions asked by researchers, and convey epistemic choices closely linked to ethical preferences. In particular, the image of the 'therapeutic missile' commonly used to present targeted drug delivery devices emphasizes precision, control, surveillance and efficiency. Such values are highly praised in the current context of crisis of pharmaceutical innovati...

  5. MITOCHONDRIA: INSIGHT TARGET OF DRUG DEVELOPMENT IN CANCER CELLS

    Directory of Open Access Journals (Sweden)

    Md. Ataur Rahman

    2012-09-01

    Full Text Available Mitochondria are involved in different physiological and pathological processes that are crucial for tumor cell physiology, growth and survival and its dysfunction leads to many human abnormalities, including cardiovascular diseases, neurodegenerative diseases, autoimmune disorders and cancer. The present review is focused on the different experimental and therapeutic cancer strategies addressed to either target mitochondria directly, or use mitochondria as mediators of apoptosis, although its total molecular mechanism has not been elucidated. Therefore, the role of mitochondria in the etiology and progression of several function and explore potential therapeutic benefits of targeting mitochondria in the disease processes. Newly evolving advances in disease diagnostics and therapy will further facilitate future growth in the field of mitochondrian biology, where there is a dire need for sensitive and more affordable diagnostic tools and an urgency to develop effective therapies and identify reliable drug to predict accurately the response to a cancer therapy. These approaches to treat mitochondrial dysfunction rationally could lead to selective protection of cells in different tissues and various disease states. To avoid mitochondrial liabilities, routine screens need to be positioned within the drug-development process as targets of drug-induced cytotoxicity or cancer promotion, as regulators of apoptosis, as sources of cell signalling through reactive oxygen species, and mitochondrial control of specific nuclear responses. However, several novel mitochondrial targets are now emerging, including the potential to manipulate the mitochondrial pool to maintain function via biogenesis and mitophagy. Forthcoming insights into the fine regulation of mitochondrial apoptosis will likely open future perspectives for cancer drug development.

  6. Decorating Nanoparticle Surface for Targeted Drug Delivery: Opportunities and Challenges

    Directory of Open Access Journals (Sweden)

    Zhiqiang Shen

    2016-03-01

    Full Text Available The size, shape, stiffness (composition and surface properties of nanoparticles (NPs have been recognized as key design parameters for NP-mediated drug delivery platforms. Among them, the surface functionalization of NPs is of great significance for targeted drug delivery. For instance, targeting moieties are covalently coated on the surface of NPs to improve their selectively and affinity to cancer cells. However, due to a broad range of possible choices of surface decorating molecules, it is difficult to choose the proper one for targeted functions. In this work, we will review several representative experimental and computational studies in selecting the proper surface functional groups. Experimental studies reveal that: (1 the NPs with surface decorated amphiphilic polymers can enter the cell interior through penetrating pathway; (2 the NPs with tunable stiffness and identical surface chemistry can be selectively accepted by the diseased cells according to their stiffness; and (3 the NPs grafted with pH-responsive polymers can be accepted or rejected by the cells due to the local pH environment. In addition, we show that computer simulations could be useful to understand the detailed physical mechanisms behind these phenomena and guide the design of next-generation NP-based drug carriers with high selectivity, affinity, and low toxicity. For example, the detailed free energy analysis and molecular dynamics simulation reveals that amphiphilic polymer-decorated NPs can penetrate into the cell membrane through the “snorkeling” mechanism, by maximizing the interaction energy between the hydrophobic ligands and lipid tails. We anticipate that this work will inspire future studies in the design of environment-responsive NPs for targeted drug delivery.

  7. Membrane-targeting liquid crystal nanoparticles (LCNPs) for drug delivery

    Science.gov (United States)

    Nag, Okhil K.; Naciri, Jawad; Spillmann, Christopher M.; Delehanty, James B.

    2016-03-01

    In addition to maintaining the structural integrity of the cell, the plasma membrane regulates multiple important cellular processes, such as endocytosis and trafficking, apoptotic pathways and drug transport. The modulation or tracking of such cellular processes by means of controlled delivery of drugs or imaging agents via nanoscale delivery systems is very attractive. Nanoparticle-mediated delivery systems that mediate long-term residence (e.g., days) and controlled release of the cargoes in the plasma membrane while simultaneously not interfering with regular cellular physiology would be ideal for this purpose. Our laboratory has developed a plasma membrane-targeted liquid crystal nanoparticle (LCNP) formulation that can be loaded with dyes or drugs which can be slowly released from the particle over time. Here we highlight the utility of these nanopreparations for membrane delivery and imaging.

  8. New alginic acid–atenolol microparticles for inhalatory drug targeting

    Energy Technology Data Exchange (ETDEWEB)

    Ceschan, Nazareth Eliana; Bucalá, Verónica [Planta Piloto de Ingeniería Química (PLAPIQUI), CONICET, Universidad Nacional del Sur (UNS), Camino La Carrindanga Km 7, 8000 Bahía Blanca (Argentina); Departamento de Ingeniería Química, UNS, Avenida Alem 1253, 8000 Bahía Blanca (Argentina); Ramírez-Rigo, María Verónica, E-mail: vrrigo@plapiqui.edu.ar [Planta Piloto de Ingeniería Química (PLAPIQUI), CONICET, Universidad Nacional del Sur (UNS), Camino La Carrindanga Km 7, 8000 Bahía Blanca (Argentina); Departamento de Biología, Bioquímica y Farmacia, UNS, San Juan 670, 8000 Bahía Blanca (Argentina)

    2014-08-01

    The inhalatory route allows drug delivery for local or systemic treatments in a noninvasively way. The current tendency of inhalable systems is oriented to dry powder inhalers due to their advantages in terms of stability and efficiency. In this work, microparticles of atenolol (AT, basic antihypertensive drug) and alginic acid (AA, acid biocompatible polyelectrolyte) were obtained by spray drying. Several formulations, varying the relative composition AT/AA and the total solid content of the atomized dispersions, were tested. The powders were characterized by: Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Powder X-ray Diffraction, while also the following properties were measured: drug load efficiency, flow properties, particles size and density, moisture content, hygroscopicity and morphology. The ionic interaction between AA and AT was demonstrated, then the new chemical entity could improve the drug targeting to the respiratory membrane and increase its time residence due to the mucoadhesive properties of the AA polymeric chains. Powders exhibited high load efficiencies, low moisture contents, adequate mean aerodynamic diameters and high cumulative fraction of respirable particles (lower than 10 μm). - Highlights: • Novel particulate material to target atenolol to the respiratory membrane was developed. • Crumbled microparticles were obtained by spray drying of alginic–atenolol dispersions. • Ionic interaction between alginic acid and atenolol was demonstrated in the product. • Amorphous solids with low moisture content and high load efficiency were produced. • Relationships between the feed formulation and the product characteristics were found.

  9. tcTKB: an integrated cardiovascular toxicity knowledge base for targeted cancer drugs

    OpenAIRE

    Xu, Rong; Wang, QuanQiu

    2015-01-01

    Targeted cancer drugs are often associated with unexpectedly high cardiovascular (CV) adverse events. Systematic approaches to studying CV events associated with targeted anticancer drugs have high potential for elucidating the complex pathways underlying targeted anti-cancer drugs. In this study, we built tcTKB, a comprehensive CV toxicity knowledge base for targeted cancer drugs, by extracting drug-CV pairs from five large-scale and complementary data sources. The data sources include FDA d...

  10. Reprofiled drug targets ancient protozoans: drug discovery for parasitic diarrheal diseases.

    Science.gov (United States)

    Debnath, Anjan; Ndao, Momar; Reed, Sharon L

    2013-01-01

    Recently, we developed a novel automated, high throughput screening (HTS) methodology for the anaerobic intestinal parasite Entamoeba histolytica. We validated this HTS platform by screening a chemical library containing US Food and Drug Administration (FDA)-approved drugs and bioactive compounds. We identified an FDA-approved drug, auranofin, as most active against E. histolytica both in vitro and in vivo. Our cell culture and animal studies indicated that thioredoxin reductase, an enzyme involved in reactive oxygen species detoxification, was the target for auranofin in E. histolytica. Here, we discuss the rationale for drug development for three parasites which are major causes of diarrhea worldwide, E. histolytica, Giardia lamblia and Cryptosporidium parvum and extend our current finding of antiparasitic activity of auranofin to Entamoeba cysts, G. lamblia and C. parvum. These studies support the use of HTS assays and reprofiling FDA-approved drugs for new therapy for neglected tropical diseases.

  11. Self-Assembling Peptide Amphiphiles for Targeted Drug Delivery

    Science.gov (United States)

    Moyer, Tyson

    The systemic delivery of therapeutics is currently limited by off-target side effects and poor drug uptake into the cells that need to be treated. One way to circumvent these issues is to target the delivery and release of therapeutics to the desired location while limiting systemic toxicity. Using self-assembling peptide amphiphiles (PAs), this work has investigated supramolecular nanostructures for the development of targeted therapies. Specifically, the research has focused on the interrelationships between presentation of targeting moeities and the control of nanostructure morphology in the context of systemic delivery for targeting cancer and vascular injuries. The self-assembly region of the PA was systematically altered to achieve control of nanostructure widths, from 100 nm to 10 nm, by the addition of valine-glutamic acid dimers into the chemical structure, subsequently increasing the degree of nanostructure twist. For the targeting of tumors, a homing PA was synthesized to include a dimeric, cyclic peptide sequence known to target the cancer-specific, death receptor 5 (DR5) and initiate apoptosis through the oligomerization of DR5. This PA presented a multivalent display of DR5-binding peptides, resulting in improved binding affinity measured by surface plasmon resonance. The DR5-targeting PA also showed enhanced efficacy in both in vitro and in vivo tumor models relative to non-targeted controls. Alternative modifications to the PA-based antitumor therapies included the use of a cytotoxic, membrane-lytic PA coassembled with a pegylated PA, which showed enhanced biodistribution and in vivo activity after coassembly. The functionalization of the hydrophobic core was also accomplished through the encapsulation of the chemotherapy camptothecin, which was shown to be an effective treatment in vivo. Additionally, a targeted PA nanostructure was designed to bind to the site of vascular intervention by targeting collagen IV. Following balloon angioplasty

  12. Cyclotriazadisulfonamides: promising new CD4-targeted anti-HIV drugs.

    Science.gov (United States)

    Vermeire, Kurt; Schols, Dominique

    2005-08-01

    It is imperative to continue efforts to identify novel effective therapies that can assist in containing the spread of HIV. Recently acquired knowledge about the HIV entry process points to new strategies to block viral entry. For most HIV strains, the successful infection of their target cells is mainly dependent on the presence of the CD4 surface molecule, which serves as the primary virus receptor. The attachment of the viral envelope to this cellular CD4 receptor can be considered as an ideal target with multiple windows of opportunity for therapeutic intervention. Therefore, drugs that interfere with the CD4 receptor, and thus inhibit viral entry, may be promising agents for the treatment of AIDS. The CD4-targeted HIV entry inhibitors cyclotriazadisulfonamides represent a novel class of small molecule antiviral agents with a unique mode of action. The lead compound, CADA, specifically interacts with the cellular CD4 receptor and is active against a wide variety of HIV strains at submicromolar levels when evaluated in different cell-types such as T cells, monocytes and dendritic cells. Moreover, a strict correlation has been demonstrated between anti-HIV activity and CD4 interaction of about 20 different CADA analogues. In addition, CADA acted synergistically in combination with all other FDA-approved anti-HIV drugs as well as with compounds that target the main HIV co-receptors. In this article, the characteristics of cyclotriazadisulfonamide compounds are presented and the possible application of CADA as a microbicide is also discussed. PMID:15980096

  13. Salinomycin as a Drug for Targeting Human Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Cord Naujokat

    2012-01-01

    Full Text Available Cancer stem cells (CSCs represent a subpopulation of tumor cells that possess self-renewal and tumor initiation capacity and the ability to give rise to the heterogenous lineages of malignant cells that comprise a tumor. CSCs possess multiple intrinsic mechanisms of resistance to chemotherapeutic drugs, novel tumor-targeted drugs, and radiation therapy, allowing them to survive standard cancer therapies and to initiate tumor recurrence and metastasis. Various molecular complexes and pathways that confer resistance and survival of CSCs, including expression of ATP-binding cassette (ABC drug transporters, activation of the Wnt/β-catenin, Hedgehog, Notch and PI3K/Akt/mTOR signaling pathways, and acquisition of epithelial-mesenchymal transition (EMT, have been identified recently. Salinomycin, a polyether ionophore antibiotic isolated from Streptomyces albus, has been shown to kill CSCs in different types of human cancers, most likely by interfering with ABC drug transporters, the Wnt/β-catenin signaling pathway, and other CSC pathways. Promising results from preclinical trials in human xenograft mice and a few clinical pilote studies reveal that salinomycin is able to effectively eliminate CSCs and to induce partial clinical regression of heavily pretreated and therapy-resistant cancers. The ability of salinomycin to kill both CSCs and therapy-resistant cancer cells may define the compound as a novel and an effective anticancer drug.

  14. Polymeric nanoparticles for targeted drug delivery system for cancer therapy.

    Science.gov (United States)

    Masood, Farha

    2016-03-01

    A targeted delivery system based on the polymeric nanoparticles as a drug carrier represents a marvelous avenue for cancer therapy. The pivotal characteristics of this system include biodegradability, biocompatibility, non-toxicity, prolonged circulation and a wide payload spectrum of a therapeutic agent. Other outstanding features are their distinctive size and shape properties for tissue penetration via an active and passive targeting, specific cellular/subcellular trafficking pathways and facile control of cargo release by sophisticated material engineering. In this review, the current implications of encapsulation of anticancer agents within polyhydroxyalkanoates, poly-(lactic-co-glycolic acid) and cyclodextrin based nanoparticles to precisely target the tumor site, i.e., cell, tissue and organ are highlighted. Furthermore, the promising perspectives in this emerging field are discussed. PMID:26706565

  15. Encapsulation of methotrexate loaded magnetic microcapsules for magnetic drug targeting and controlled drug release

    Energy Technology Data Exchange (ETDEWEB)

    Chakkarapani, Prabu [Department of Pharmaceutical Technology & Centre for Excellence in Nanobio Translational Research, Anna University, Bharathidasan Institute of Technology Campus, Tiruchirappalli 620024, Tamil Nadu (India); Subbiah, Latha, E-mail: lathasuba2010@gmail.com [Department of Pharmaceutical Technology & Centre for Excellence in Nanobio Translational Research, Anna University, Bharathidasan Institute of Technology Campus, Tiruchirappalli 620024, Tamil Nadu (India); Palanisamy, Selvamani; Bibiana, Arputha [Department of Pharmaceutical Technology & Centre for Excellence in Nanobio Translational Research, Anna University, Bharathidasan Institute of Technology Campus, Tiruchirappalli 620024, Tamil Nadu (India); Ahrentorp, Fredrik; Jonasson, Christian; Johansson, Christer [Acreo Swedish ICT AB, Arvid Hedvalls backe 4, SE-411 33 Göteborg (Sweden)

    2015-04-15

    We report on the development and evaluation of methotrexate magnetic microcapsules (MMC) for targeted rheumatoid arthritis therapy. Methotrexate was loaded into CaCO{sub 3}-PSS (poly (sodium 4-styrenesulfonate)) doped microparticles that were coated successively with poly (allylamine hydrochloride) and poly (sodium 4-styrenesulfonate) by layer-by-layer technique. Ferrofluid was incorporated between the polyelectrolyte layers. CaCO{sub 3}-PSS core was etched by incubation with EDTA yielding spherical MMC. The MMC were evaluated for various physicochemical, pharmaceutical parameters and magnetic properties. Surface morphology, crystallinity, particle size, zeta potential, encapsulation efficiency, loading capacity, drug release pattern, release kinetics and AC susceptibility studies revealed spherical particles of ~3 µm size were obtained with a net zeta potential of +24.5 mV, 56% encapsulation and 18.6% drug loading capacity, 96% of cumulative drug release obeyed Hixson-Crowell model release kinetics. Drug excipient interaction, surface area, thermal and storage stability studies for the prepared MMC was also evaluated. The developed MMC offer a promising mode of targeted and sustained release drug delivery for rheumatoid arthritis therapy. - Highlights: • Development of methotrexate magnetic microcapsules (MMC) by layer-by-layer method. • Characterization of physicochemical, pharmaceutical and magnetic properties of MMC. • Multiple layers of alternative polyelectrolytes prolongs methotrexate release time. • MMC is capable for targeted and sustained release rheumatoid arthritis therapy.

  16. Encapsulation of methotrexate loaded magnetic microcapsules for magnetic drug targeting and controlled drug release

    International Nuclear Information System (INIS)

    We report on the development and evaluation of methotrexate magnetic microcapsules (MMC) for targeted rheumatoid arthritis therapy. Methotrexate was loaded into CaCO3-PSS (poly (sodium 4-styrenesulfonate)) doped microparticles that were coated successively with poly (allylamine hydrochloride) and poly (sodium 4-styrenesulfonate) by layer-by-layer technique. Ferrofluid was incorporated between the polyelectrolyte layers. CaCO3-PSS core was etched by incubation with EDTA yielding spherical MMC. The MMC were evaluated for various physicochemical, pharmaceutical parameters and magnetic properties. Surface morphology, crystallinity, particle size, zeta potential, encapsulation efficiency, loading capacity, drug release pattern, release kinetics and AC susceptibility studies revealed spherical particles of ~3 µm size were obtained with a net zeta potential of +24.5 mV, 56% encapsulation and 18.6% drug loading capacity, 96% of cumulative drug release obeyed Hixson-Crowell model release kinetics. Drug excipient interaction, surface area, thermal and storage stability studies for the prepared MMC was also evaluated. The developed MMC offer a promising mode of targeted and sustained release drug delivery for rheumatoid arthritis therapy. - Highlights: • Development of methotrexate magnetic microcapsules (MMC) by layer-by-layer method. • Characterization of physicochemical, pharmaceutical and magnetic properties of MMC. • Multiple layers of alternative polyelectrolytes prolongs methotrexate release time. • MMC is capable for targeted and sustained release rheumatoid arthritis therapy

  17. Lymphatic Targeting of Nanosystems for Anticancer Drug Therapy.

    Science.gov (United States)

    Abellan-Pose, Raquel; Csaba, Noemi; Alonso, Maria Jose

    2016-01-01

    The lymphatic system represents a major route of dissemination in metastatic cancer. Given the lack of selectivity of conventional chemotherapy to prevent lymphatic metastasis, in the last years there has been a growing interest in the development of nanocarriers showing lymphotropic characteristics. The goal of this lymphotargeting strategy is to facilitate the delivery of anticancer drugs to the lymph node-resident cancer cells, thereby enhancing the effectiveness of the anti-cancer therapies. This article focuses on the nanosystems described so far for the active or passive targeting of oncological drugs to the lymphatic circulation. To understand the design and performance of these nanosystems, we will discuss first the physiology of the lymphatic system and how physiopathological changes associated to tumor growth influence the biodistribution of nanocarriers. Second, we provide evidence on how the tailoring of the physicochemical characteristics of nanosystems, i.e. particle size, surface charge and hydrophilicity, allows the modulation of their access to the lymphatic circulation. Finally, we provide an overview of the relationship between the biodistribution and antimetastatic activity of the nanocarriers loaded with oncological drugs, and illustrate the most promising active targeting approaches investigated so far. PMID:26675222

  18. Targeted Tumor Therapy with "Magnetic Drug Targeting": Therapeutic Efficacy of Ferrofluid Bound Mitoxantrone

    Science.gov (United States)

    Alexiou, Ch.; Schmid, R.; Jurgons, R.; Bergemann, Ch.; Arnold, W.; Parak, F.G.

    The difference between success or failure of chemotherapy depends not only on the drug itself but also on how it is delivered to its target. Biocompatible ferrofluids (FF) are paramagnetic nanoparticles, that may be used as a delivery system for anticancer agents in locoregional tumor therapy, called "magnetic drug targeting". Bound to medical drugs, such magnetic nanoparticles can be enriched in a desired body compartment (tumor) using an external magnetic field, which is focused on the area of the tumor. Through this form of target directed drug application, one attempts to concentrate a pharmacological agent at its site of action in order to minimize unwanted side effects in the organism and to increase its locoregional effectiveness. Tumor bearing rabbits (VX2 squamous cell carcinoma) in the area of the hind limb, were treated by a single intra-arterial injection (A. femoralis) of mitoxantrone bound ferrofluids (FF-MTX), while focusing an external magnetic field (1.7 Tesla) onto the tumor for 60 minutes. Complete tumor remissions could be achieved in these animals in a dose related manner (20% and 50% of the systemic dose of mitoxantrone), without any negative side effects, like e.g. leucocytopenia, alopecia or gastrointestinal disorders. The strong and specific therapeutic efficacy in tumor treatment with mitoxantrone bound ferrofluids may indicate that this system could be used as a delivery system for anticancer agents, like radionuclids, cancer-specific antibodies, anti-angiogenetic factors, genes etc.

  19. Electrospun Nanofibers of Guar Galactomannan for Targeted Drug Delivery

    Science.gov (United States)

    Chu, Hsiao Mei Annie

    2011-12-01

    Guar galactomannan is a biodegradable polysaccharide used widely in the food industry but also in the cosmetics, pharmaceutical, oil drilling, textile and paper industries. Guar consists of a mannose backbone and galactose side groups that are both susceptible to enzyme degradation, a unique property that can be explored for targeted drug delivery especially since those enzymes are naturally secreted by the microflora in human colon. The present study can be divided into three parts. In the first part, we discuss ways to modify guar to produce nanofibers by electrospinning, a process that involves the application of an electric field to a polymer solution or melt to facilitate production of fibers in the sub-micron range. Nanofibers are currently being explored as the next generation of drug carriers due to its many advantages, none more important than the fact that nanofibers are on a size scale that is a fraction of a hair's width and have large surface-to-volume ratio. The incorporation and controlled release of nano-sized drugs is one way in which nanofibers are being utilized in drug delivery. In the second part of the study, we explore various methods to crosslink guar nanofibers as a means to promote water-resistance in a potential drug carrier. The scope and utility of water-resistant guar nanofibers can only be fully appreciated when subsequent drug release studies are carried out. To that end, the third part of our study focuses on understanding the kinetics and diffusion mechanisms of a model drug, Rhodamine B, through moderately-swelling (crosslinked) hydrogel nanofibers in comparison to rapidly-swelling (non-crosslinked) nanofibers. Along the way, our investigations led us to a novel electrospinning set-up that has a unique collector designed to capture aligned nanofibers. These aligned nanofiber bundles can then be twisted to hold them together like yarn. From a practical standpoint, these yarns are advantageous because they come freely suspended and

  20. Targeting the treatment of drug abuse with molecular imaging

    International Nuclear Information System (INIS)

    Although imaging studies in and of themselves have significant contributions to the study of human behavior, imaging in drug abuse has a much broader agenda. Drugs of abuse bind to molecules in specific parts of the brain in order to produce their effects. Positron emission tomography (PET) provides a unique opportunity to track this process, capturing the kinetics with which an abused compound is transported to its site of action. The specific examples discussed here were chosen to illustrate how PET can be used to map the regional distribution and kinetics of compounds that may or may not have abuse liability. We also discussed some morphological and functional changes associated with drug abuse and different stages of recovery following abstinence. PET measurements of functional changes in the brain have also led to the development of several treatment strategies, one of which is discussed in detail here. Information such as this becomes more than a matter of academic interest. Such knowledge can provide the bases for anticipating which compounds may be abused and which may not. It can also be used to identify biological markers or changes in brain function that are associated with progression from drug use to drug abuse and also to stage the recovery process. This new knowledge can guide legislative initiatives on the optimal duration of mandatory treatment stays, promoting long-lasting abstinence and greatly reducing the societal burden of drug abuse. Imaging can also give some insights into potential pharmacotherapeutic targets to manage the reinforcing effects of addictive compounds, as well as into protective strategies to minimize their toxic consequences

  1. Pharmacoinformatics elucidation of potential drug targets against migraine to target ion channel protein KCNK18.

    Science.gov (United States)

    Sehgal, Sheikh Arslan; Hassan, Mubashir; Rashid, Sajid

    2014-01-01

    Migraine, a complex debilitating neurological disorder is strongly associated with potassium channel subfamily K member 18 (KCNK18). Research has emphasized that high levels of KCNK18 may be responsible for improper functioning of neurotransmitters, resulting in neurological disorders like migraine. In the present study, a hybrid approach of molecular docking and virtual screening were followed by pharmacophore identification and structure modeling. Screening was performed using a two-dimensional similarity search against recommended migraine drugs, keeping in view the physicochemical properties of drugs. LigandScout tool was used for exploring pharmacophore properties and designing novel molecules. Here, we report the screening of four novel compounds that have showed maximum binding affinity against KCNK18, obtained through the ZINC database, and Drug and Drug-Like libraries. Docking studies revealed that Asp-46, Ile-324, Ile-44, Gly-118, Leu-338, Val-113, and Phe-41 are critical residues for receptor-ligand interaction. A virtual screening approach coupled with docking energies and druglikeness rules illustrated that ergotamine and PB-414901692 are potential inhibitor compounds for targeting KCNK18. We propose that selected compounds may be more potent than the previously listed drug analogs based on the binding energy values. Further analysis of these inhibitors through site-directed mutagenesis could be helpful for exploring the details of ligand-binding pockets. Overall, the findings of this study may be helpful for designing novel therapeutic targets to cure migraine. PMID:24899801

  2. Dual responsive PNIPAM–chitosan targeted magnetic nanopolymers for targeted drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Yadavalli, Tejabhiram, E-mail: tejabhiram@gmail.com [Nanotechnology Research Centre, SRM University, Chennai 603203 (India); Ramasamy, Shivaraman [Nanotechnology Research Centre, SRM University, Chennai 603203 (India); School of Physics, The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009 (Australia); Chandrasekaran, Gopalakrishnan; Michael, Isaac; Therese, Helen Annal [Nanotechnology Research Centre, SRM University, Chennai 603203 (India); Chennakesavulu, Ramasamy [Department of Pharmacy practice, SRM College of Pharmacy, Chennai 603203 (India)

    2015-04-15

    A dual stimuli sensitive magnetic hyperthermia based drug delivery system has been developed for targeted cancer treatment. Thermosensitive amine terminated poly-N-isopropylacrylamide complexed with pH sensitive chitosan nanoparticles was prepared as the drug carrier. Folic acid and fluorescein were tagged to the nanopolymer complex via N-hydroxysuccinimide and ethyl-3-(3-dimethylaminopropyl)carbodiimide reaction to form a fluorescent and cancer targeting magnetic carrier system. The formation of the polymer complex was confirmed using infrared spectroscopy. Gadolinium doped nickel ferrite nanoparticles prepared by a hydrothermal method were encapsulated in the polymer complex to form a magnetic drug carrier system. The proton relaxation studies on the magnetic carrier system revealed a 200% increase in the T1 proton relaxation rate. These magnetic carriers were loaded with curcumin using solvent evaporation method with a drug loading efficiency of 86%. Drug loaded nanoparticles were tested for their targeting and anticancer properties on four cancer cell lines with the help of MTT assay. The results indicated apoptosis of cancer cell lines within 3 h of incubation. - Highlights: • The use of gadolinium doped nickel ferrite with the suggested doping level. • The use of PNIPMA–chitosan polymer with folic acid and fluorescein as a drug carrier complex. • Magnetic hyperthermia studies of gadolinium doped nickel ferrites are being reported for the first time. • Proton relaxivity studies which indicate the MRI contrasting properties on the reported system are new. • Use of curcumin, a hydrophobic Indian spice as a cancer killing agent inside the reported magnetic polymer complex.

  3. Dual responsive PNIPAM–chitosan targeted magnetic nanopolymers for targeted drug delivery

    International Nuclear Information System (INIS)

    A dual stimuli sensitive magnetic hyperthermia based drug delivery system has been developed for targeted cancer treatment. Thermosensitive amine terminated poly-N-isopropylacrylamide complexed with pH sensitive chitosan nanoparticles was prepared as the drug carrier. Folic acid and fluorescein were tagged to the nanopolymer complex via N-hydroxysuccinimide and ethyl-3-(3-dimethylaminopropyl)carbodiimide reaction to form a fluorescent and cancer targeting magnetic carrier system. The formation of the polymer complex was confirmed using infrared spectroscopy. Gadolinium doped nickel ferrite nanoparticles prepared by a hydrothermal method were encapsulated in the polymer complex to form a magnetic drug carrier system. The proton relaxation studies on the magnetic carrier system revealed a 200% increase in the T1 proton relaxation rate. These magnetic carriers were loaded with curcumin using solvent evaporation method with a drug loading efficiency of 86%. Drug loaded nanoparticles were tested for their targeting and anticancer properties on four cancer cell lines with the help of MTT assay. The results indicated apoptosis of cancer cell lines within 3 h of incubation. - Highlights: • The use of gadolinium doped nickel ferrite with the suggested doping level. • The use of PNIPMA–chitosan polymer with folic acid and fluorescein as a drug carrier complex. • Magnetic hyperthermia studies of gadolinium doped nickel ferrites are being reported for the first time. • Proton relaxivity studies which indicate the MRI contrasting properties on the reported system are new. • Use of curcumin, a hydrophobic Indian spice as a cancer killing agent inside the reported magnetic polymer complex

  4. A conceptual framework for the identification of candidate drugs and drug targets in acute promyelocytic leukemia

    DEFF Research Database (Denmark)

    Marstrand, T T; Borup, R; Willer, A;

    2010-01-01

    regulation, and (ii) the identification of candidate drugs and drug targets for therapeutic interventions. Significantly, our study provides a conceptual framework that can be applied to any subtype of AML and cancer in general to uncover novel information from published microarray data sets at low cost......Chromosomal translocations of transcription factors generating fusion proteins with aberrant transcriptional activity are common in acute leukemia. In acute promyelocytic leukemia (APL), the promyelocytic leukemia-retinoic-acid receptor alpha (PML-RARA) fusion protein, which emerges....... In a broader perspective, our study provides strong evidence that genomic strategies might be used in a clinical setting to prospectively identify candidate drugs that subsequently are validated in vitro to define the most effective drug combination for individual cancer patients on a rational basis....

  5. Quantification of biodegradable PLGA nanoparticles for drug targeting

    Directory of Open Access Journals (Sweden)

    Nadira Ibrišimović

    2010-11-01

    Full Text Available Objective. The aim of this work was the development of appropriate analytical methods and assays for determining and monitoring composition and degradation of nanoparticles built from PLGA (poly D, L-lactid-co-glycolid, which can be reloaded with different drugs. A sensitive and precise method for monitoring of nanoparticle degradation in vitro was developed and optimized. Nanoparticles allow a selective enrichment of different drugs and knowledge of the nature and type of their degradation is essential for characterization and control of drug release and dosage. Materials and methods. The first method developed during this work to quantify the PLGA polymer matrix use advantage of the chemical reaction of aliphatic carboxylic acids with ferric chloride (FeCl3 thus quantifying both degradation products of PLGA, lactic and glycol acids, at the same time. A second assay method of choice was to react to the polymer hydrolysate with lactate dehydrogenase, thus assaying selectively the lactic acid part. Results. During development of both of described methods was possible to determine dynamic range for PLGA matrix and nanoparticles, as well as to characterize impact of Pluronic F-68 and glycolic acid on lactate dehydrogenase activity. Conclusion. During our work we were able to develop two sensitive methods for monitoring of biodegradation of polymers which are consecutively used as a nanoparticle matrix in drug targeting.

  6. Magnetically responsive microparticles for targeted drug and radionuclide delivery.

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, M. D.; Ghebremeskel, A. N.; Nunez, L.; Kasza, K. E.; Chang, F.; Chien, T.-H.; Fisher, P. F.; Eastman, J. A.; Rosengart, A. J.; McDonald, L.; Xie, Y.; Johns, L.; Pytel, P.; Hafeli, U. O.

    2004-02-16

    We are currently investigating the use of magnetic particles--polymeric-based spheres containing dispersed magnetic nanocrystalline phases--for the precise delivery of drugs via the human vasculature. According to this review, meticulously prepared magnetic drug targeting holds promise as a safe and effective method of delivering drugs to specific organ, tissue or cellular targets. We have critically examined the wide range of approaches in the design and implementation of magnetic-particle-based drug delivery systems to date, including magnetic particle preparation, drug encapsulation, biostability, biocompatibility, toxicity, magnetic field designs, and clinical trials. However, we strongly believe that there are several limitations with past developments that need to be addressed to enable significant strides in the field. First, particle size has to be carefully chosen. Micrometer-sized magnetic particles are better attracted over a distance than nanometer sized magnetic particles by a constant magnetic field gradient, and particle sizes up to 1 {micro}m show a much better accumulation with no apparent side effects in small animal models, since the smallest blood vessels have an inner diameter of 5-7 {micro}m. Nanometer-sized particles <70 nm will accumulate in organ fenestrations despite an effective surface stabilizer. To be suitable for future human applications, our experimental approach synthesizes the magnetic drug carrier according to specific predefined outcome metrics: monodisperse population in a size range of 100 nm to 1.0 {micro}m, non-toxic, with appropriate magnetic properties, and demonstrating successful in vitro and in vivo tests. Another important variable offering possible improvement is surface polarity, which is expected to prolong particle half-life in circulation and modify biodistribution and stability of drugs in the body. The molecules in the blood that are responsible for enhancing the uptake of particles by the reticuloendothelial

  7. Chronic neuropathic pain: mechanisms, drug targets and measurement

    DEFF Research Database (Denmark)

    Finnerup, Nanna Brix; Sindrup, Søren H.; Jensen, Troels Staehelin

    2007-01-01

    Neuropathic pain is common in many diseases or injuries of the peripheral or central nervous system, and has a substantial impact on quality of life and mood. Lesions of the nervous system may lead to potentially irreversible changes and imbalance between excitatory and inhibitory systems. Precli...... assess various symptoms and signs in neuropathic pain and knowledge of drug mechanisms are prerequisites for pursuing this approach. The present review summarizes mechanisms of neuropathic pain, targets of currently used drugs, and measures used in neuropathic pain trials.......Neuropathic pain is common in many diseases or injuries of the peripheral or central nervous system, and has a substantial impact on quality of life and mood. Lesions of the nervous system may lead to potentially irreversible changes and imbalance between excitatory and inhibitory systems...

  8. Genetic Validation of Aminoacyl-tRNA Synthetases as Drug Targets in Trypanosoma brucei

    OpenAIRE

    Kalidas, Savitha; Cestari, Igor; Monnerat, Severine; Li, Qiong; Regmi, Sandesh; Hasle, Nicholas; Labaied, Mehdi; Parsons, Marilyn; Stuart, Kenneth; Phillips, Margaret A.

    2014-01-01

    Human African trypanosomiasis (HAT) is an important public health threat in sub-Saharan Africa. Current drugs are unsatisfactory, and new drugs are being sought. Few validated enzyme targets are available to support drug discovery efforts, so our goal was to obtain essentiality data on genes with proven utility as drug targets. Aminoacyl-tRNA synthetases (aaRSs) are known drug targets for bacterial and fungal pathogens and are required for protein synthesis. Here we survey the essentiality of...

  9. Nanomechanics of drug-target interactions and antibacterial resistance detection.

    Science.gov (United States)

    Ndieyira, Joseph W; Watari, Moyu; McKendry, Rachel A

    2013-01-01

    The cantilever sensor, which acts as a transducer of reactions between model bacterial cell wall matrix immobilized on its surface and antibiotic drugs in solution, has shown considerable potential in biochemical sensing applications with unprecedented sensitivity and specificity. The drug-target interactions generate surface stress, causing the cantilever to bend, and the signal can be analyzed optically when it is illuminated by a laser. The change in surface stress measured with nano-scale precision allows disruptions of the biomechanics of model bacterial cell wall targets to be tracked in real time. Despite offering considerable advantages, multiple cantilever sensor arrays have never been applied in quantifying drug-target binding interactions. Here, we report on the use of silicon multiple cantilever arrays coated with alkanethiol self-assembled monolayers mimicking bacterial cell wall matrix to quantitatively study antibiotic binding interactions. To understand the impact of vancomycin on the mechanics of bacterial cell wall structures. We developed a new model(1) which proposes that cantilever bending can be described by two independent factors; i) namely a chemical factor, which is given by a classical Langmuir adsorption isotherm, from which we calculate the thermodynamic equilibrium dissociation constant (Kd) and ii) a geometrical factor, essentially a measure of how bacterial peptide receptors are distributed on the cantilever surface. The surface distribution of peptide receptors (p) is used to investigate the dependence of geometry and ligand loading. It is shown that a threshold value of p ~10% is critical to sensing applications. Below which there is no detectable bending signal while above this value, the bending signal increases almost linearly, revealing that stress is a product of a local chemical binding factor and a geometrical factor combined by the mechanical connectivity of reacted regions and provides a new paradigm for design of powerful

  10. TRPV1: A Target for Rational Drug Design.

    Science.gov (United States)

    Carnevale, Vincenzo; Rohacs, Tibor

    2016-01-01

    Transient Receptor Potential Vanilloid 1 (TRPV1) is a non-selective, Ca(2+) permeable cation channel activated by noxious heat, and chemical ligands, such as capsaicin and resiniferatoxin (RTX). Many compounds have been developed that either activate or inhibit TRPV1, but none of them are in routine clinical practice. This review will discuss the rationale for antagonists and agonists of TRPV1 for pain relief and other conditions, and strategies to develop new, better drugs to target this ion channel, using the newly available high-resolution structures. PMID:27563913

  11. Calculation of nanoparticle capture efficiency in magnetic drug targeting

    International Nuclear Information System (INIS)

    The implant assisted magnetic targeted drug delivery system of Aviles, Ebner and Ritter, which uses high gradient magnetic separation (HGMS) is considered. In this 2D model large ferromagnetic particles are implanted as seeds to aid collection of multiple domain nanoparticles (radius ∼200nm). Here, in contrast, single domain magnetic nanoparticles (radius in 20-100 nm) are considered and the Langevin function is used to describe the magnetization. Simulations based on this model were performed using the open source C++ finite volume library OpenFOAM. The simulations indicate that use of the Langevin function predicts greater collection efficiency than might be otherwise expected

  12. Mining nematode genome data for novel drug targets.

    Science.gov (United States)

    Foster, Jeremy M; Zhang, Yinhua; Kumar, Sanjay; Carlow, Clotilde K S

    2005-03-01

    Expressed sequence tag projects have currently produced over 400 000 partial gene sequences from more than 30 nematode species and the full genomic sequences of selected nematodes are being determined. In addition, functional analyses in the model nematode Caenorhabditis elegans have addressed the role of almost all genes predicted by the genome sequence. This recent explosion in the amount of available nematode DNA sequences, coupled with new gene function data, provides an unprecedented opportunity to identify pre-validated drug targets through efficient mining of nematode genomic databases. This article describes the various information sources available and strategies that can expedite this process.

  13. Virtual target screening to rapidly identify potential protein targets of natural products in drug discovery

    Directory of Open Access Journals (Sweden)

    Yuri Pevzner

    2014-05-01

    Full Text Available Inherent biological viability and diversity of natural products make them a potentially rich source for new therapeutics. However, identification of bioactive compounds with desired therapeutic effects and identification of their protein targets is a laborious, expensive process. Extracts from organism samples may show desired activity in phenotypic assays but specific bioactive compounds must be isolated through further separation methods and protein targets must be identified by more specific phenotypic and in vitro experimental assays. Still, questions remain as to whether all relevant protein targets for a compound have been identified. The desire is to understand breadth of purposing for the compound to maximize its use and intellectual property, and to avoid further development of compounds with insurmountable adverse effects. Previously we developed a Virtual Target Screening system that computationally screens one or more compounds against a collection of virtual protein structures. By scoring each compound-protein interaction, we can compare against averaged scores of synthetic drug-like compounds to determine if a particular protein would be a potential target of a compound of interest. Here we provide examples of natural products screened through our system as we assess advantages and shortcomings of our current system in regards to natural product drug discovery.

  14. Development of modified pulsincap drug delivery system of metronidazole for drug targeting

    Directory of Open Access Journals (Sweden)

    Abraham Sindhu

    2007-01-01

    Full Text Available A modified Pulsincap dosage form of metronidazole was developed to target drug release in the colon. Bodies of hard gelatin capsules were treated with formaldehyde keeping the caps as such. Metronidazole pellets prepared by extrusion-spheronization method were incorporated into these specialized capsule shells and plugged with polymers guar gum, hydroxypropylmethylcellulose 10K, carboxymethylcellulose sodium and sodium alginate separately at concentrations 20 mg, 30 mg and 40 mg. The filled capsules were completely coated with 5% cellulose acetate phthalate to prevent variable gastric emptying. All the formulations were assayed to determine drug content and the ability of the modified Pulsincap to provide colon-specific drug delivery was assessed by in vitro drug release studies in buffer pH 1.2 for 2 h, pH 7.4 (simulated intestinal fluid for 3 h and pH 6.8 (stimulated colonic fluid for 7 h. The results indicated that significant drug release occurred only after 5 h from the start of experiment. Thus, metronidazole could be successfully colon targeted by the use of the modified Pulsincap, thereby reducing systemic side effects.

  15. Tumor Targeting and Drug Delivery by Anthrax Toxin.

    Science.gov (United States)

    Bachran, Christopher; Leppla, Stephen H

    2016-01-01

    Anthrax toxin is a potent tripartite protein toxin from Bacillus anthracis. It is one of the two virulence factors and causes the disease anthrax. The receptor-binding component of the toxin, protective antigen, needs to be cleaved by furin-like proteases to be activated and to deliver the enzymatic moieties lethal factor and edema factor to the cytosol of cells. Alteration of the protease cleavage site allows the activation of the toxin selectively in response to the presence of tumor-associated proteases. This initial idea of re-targeting anthrax toxin to tumor cells was further elaborated in recent years and resulted in the design of many modifications of anthrax toxin, which resulted in successful tumor therapy in animal models. These modifications include the combination of different toxin variants that require activation by two different tumor-associated proteases for increased specificity of toxin activation. The anthrax toxin system has proved to be a versatile system for drug delivery of several enzymatic moieties into cells. This highly efficient delivery system has recently been further modified by introducing ubiquitin as a cytosolic cleavage site into lethal factor fusion proteins. This review article describes the latest developments in this field of tumor targeting and drug delivery. PMID:27376328

  16. Epigenetic drugs that do not target enzyme activity.

    Science.gov (United States)

    Owen, Dafydd R; Trzupek, John D

    2014-06-01

    While the installation and removal of epigenetic post-translational modifications or ‘marks’ on both DNA and histone proteins are the tangible outcome of enzymatically catalyzed processes, the role of the epigenetic reader proteins looks, at first, less obvious. As they do not catalyze a chemical transformation or process as such, their role is not enzymatic. However, this does not preclude them from being potential targets for drug discovery as their function is clearly correlated to transcriptional activity and as a class of proteins, they appear to have binding sites of sufficient definition and size to be inhibited by small molecules. This suggests that this third class of epigenetic proteins that are involved in the interpretation of post-translational marks (as opposed to the creation or deletion of marks) may represent attractive targets for drug discovery efforts. This review mainly summarizes selected publications, patent literature and company disclosures on these non-enzymatic epigenetic reader proteins from 2009 to the present.

  17. Predicting enzyme targets for cancer drugs by profiling human Metabolic reactions in NCI-60 cell lines

    Directory of Open Access Journals (Sweden)

    Ching Wai-Ki

    2010-10-01

    Full Text Available Abstract Background Drugs can influence the whole metabolic system by targeting enzymes which catalyze metabolic reactions. The existence of interactions between drugs and metabolic reactions suggests a potential way to discover drug targets. Results In this paper, we present a computational method to predict new targets for approved anti-cancer drugs by exploring drug-reaction interactions. We construct a Drug-Reaction Network to provide a global view of drug-reaction interactions and drug-pathway interactions. The recent reconstruction of the human metabolic network and development of flux analysis approaches make it possible to predict each metabolic reaction's cell line-specific flux state based on the cell line-specific gene expressions. We first profile each reaction by its flux states in NCI-60 cancer cell lines, and then propose a kernel k-nearest neighbor model to predict related metabolic reactions and enzyme targets for approved cancer drugs. We also integrate the target structure data with reaction flux profiles to predict drug targets and the area under curves can reach 0.92. Conclusions The cross validations using the methods with and without metabolic network indicate that the former method is significantly better than the latter. Further experiments show the synergism of reaction flux profiles and target structure for drug target prediction. It also implies the significant contribution of metabolic network to predict drug targets. Finally, we apply our method to predict new reactions and possible enzyme targets for cancer drugs.

  18. Drug-target interaction prediction by random walk on the heterogeneous network.

    Science.gov (United States)

    Chen, Xing; Liu, Ming-Xi; Yan, Gui-Ying

    2012-07-01

    Predicting potential drug-target interactions from heterogeneous biological data is critical not only for better understanding of the various interactions and biological processes, but also for the development of novel drugs and the improvement of human medicines. In this paper, the method of Network-based Random Walk with Restart on the Heterogeneous network (NRWRH) is developed to predict potential drug-target interactions on a large scale under the hypothesis that similar drugs often target similar target proteins and the framework of Random Walk. Compared with traditional supervised or semi-supervised methods, NRWRH makes full use of the tool of the network for data integration to predict drug-target associations. It integrates three different networks (protein-protein similarity network, drug-drug similarity network, and known drug-target interaction networks) into a heterogeneous network by known drug-target interactions and implements the random walk on this heterogeneous network. When applied to four classes of important drug-target interactions including enzymes, ion channels, GPCRs and nuclear receptors, NRWRH significantly improves previous methods in terms of cross-validation and potential drug-target interaction prediction. Excellent performance enables us to suggest a number of new potential drug-target interactions for drug development.

  19. Nanomaterials for the Local and Targeted Delivery of Osteoarthritis Drugs

    Directory of Open Access Journals (Sweden)

    Parthiban Chinnagounder Periyasamy

    2012-01-01

    Full Text Available Nanotechnology has found its potential in every possible field of science and engineering. It offers a plethora of options to design tools at the nanometer scale, which can be expected to function more effectively than micro- and macrosystems for specific applications. Although the debate regarding the safety of synthetic nanomaterials for clinical applications endures, it is a promising technology due to its potential to augment current treatments. Various materials such as synthetic polymer, biopolymers, or naturally occurring materials such as proteins and peptides can serve as building blocks for adaptive nanoscale formulations. The choice of materials depends highly on the application. We focus on the use of nanoparticles for the treatment of degenerative cartilage diseases, such as osteoarthritis (OA. Current therapies for OA focus on treating the symptoms rather than modifying the disease. The usefulness of OA disease modifying drugs is hampered by side effects and lack of suitable drug delivery systems that target, deliver, and retain drugs locally. This challenge can be overcome by using nanotechnological formulations. We describe the different nanodrug delivery systems and their potential for cartilage repair. This paper provides the reader basal understanding of nanomaterials and aims at drawing new perspectives on the use of existing nanotechnological formulations for the treatment of osteoarthritis.

  20. New drugs targeting Th2 lymphocytes in asthma.

    Science.gov (United States)

    Caramori, Gaetano; Groneberg, David; Ito, Kazuhiro; Casolari, Paolo; Adcock, Ian M; Papi, Alberto

    2008-02-27

    Asthma represents a profound worldwide public health problem. The most effective anti-asthmatic drugs currently available include inhaled beta2-agonists and glucocorticoids and control asthma in about 90-95% of patients. The current asthma therapies are not cures and symptoms return soon after treatment is stopped even after long term therapy. Although glucocorticoids are highly effective in controlling the inflammatory process in asthma, they appear to have little effect on the lower airway remodelling processes that appear to play a role in the pathophysiology of asthma at currently prescribed doses. The development of novel drugs may allow resolution of these changes. In addition, severe glucocorticoid-dependent and resistant asthma presents a great clinical burden and reducing the side-effects of glucocorticoids using novel steroid-sparing agents is needed. Furthermore, the mechanisms involved in the persistence of inflammation are poorly understood and the reasons why some patients have severe life threatening asthma and others have very mild disease are still unknown. Drug development for asthma has been directed at improving currently available drugs and findings new compounds that usually target the Th2-driven airway inflammatory response. Considering the apparently central role of T lymphocytes in the pathogenesis of asthma, drugs targeting disease-inducing Th2 cells are promising therapeutic strategies. However, although animal models of asthma suggest that this is feasible, the translation of these types of studies for the treatment of human asthma remains poor due to the limitations of the models currently used. The myriad of new compounds that are in development directed to modulate Th2 cells recruitment and/or activation will clarify in the near future the relative importance of these cells and their mediators in the complex interactions with the other pro-inflammatory/anti-inflammatory cells and mediators responsible of the different asthmatic

  1. Micro RNA, A Review: Pharmacogenomic drug targets for complex diseases

    Directory of Open Access Journals (Sweden)

    Ritesh Bajaj

    2010-01-01

    Full Text Available Micro RNAs (miRNAs are non-coding RNAs that can regulate gene expression to target several mRNAs in a gene regulatory network. MiRNA related Single Nucleotide Polymorphisms (S.N.P.s represent a newly identified type of genetic variability that can be of influence to the risk of certain human diseases and also affect how drugs can be activated and metabolized by patients. This will help in personalized medicines which are used for adminis-trating the correct dosage of drug and drug efficacy. miRNA deregulated expression has been extensively de-scribed in a variety of diseases such as Cancer, Obesity , Diabetes, Schizophrenia and control and self renewal of stem cells. MiRNA can function as oncogenes and/or tumor suppressors. MiRNAs may act as key regulators of processes as diverse as early development, cell proliferation and cell death, apoptosis and fat metabolism and cell differentiation .miRNA expression have shown their role in brain development chronic lymphocytic leukemia, colonic adeno carcinoma, Burkiff′s lymphoma and viral infection. These show their links with viral disease, neu-rodevelopment and cancer. It has been shown that they play a key role in melanoma metastasis. These may be differentially expressed in malignant cells compared to normal cells altering the regulation of expression of many important genes. MiRNA expression has been used for prognosis and early diagnosis of these complex diseases. The present paper focuses on the role of miRNAs in various complex diseases, which will help in improving the drug discovery process and personalized medicines.

  2. Pharmacoinformatics elucidation of potential drug targets against migraine to target ion channel protein KCNK18

    Directory of Open Access Journals (Sweden)

    Sehgal SA

    2014-05-01

    Full Text Available Sheikh Arslan Sehgal, Mubashir Hassan, Sajid Rashid National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan Abstract: Migraine, a complex debilitating neurological disorder is strongly associated with potassium channel subfamily K member 18 (KCNK18. Research has emphasized that high levels of KCNK18 may be responsible for improper functioning of neurotransmitters, resulting in neurological disorders like migraine. In the present study, a hybrid approach of molecular docking and virtual screening were followed by pharmacophore identification and structure modeling. Screening was performed using a two-dimensional similarity search against recommended migraine drugs, keeping in view the physicochemical properties of drugs. LigandScout tool was used for exploring pharmacophore properties and designing novel molecules. Here, we report the screening of four novel compounds that have showed maximum binding affinity against KCNK18, obtained through the ZINC database, and Drug and Drug-Like libraries. Docking studies revealed that Asp-46, Ile-324, Ile-44, Gly-118, Leu-338, Val-113, and Phe-41 are critical residues for receptor–ligand interaction. A virtual screening approach coupled with docking energies and druglikeness rules illustrated that ergotamine and PB-414901692 are potential inhibitor compounds for targeting KCNK18. We propose that selected compounds may be more potent than the previously listed drug analogs based on the binding energy values. Further analysis of these inhibitors through site-directed mutagenesis could be helpful for exploring the details of ligand-binding pockets. Overall, the findings of this study may be helpful for designing novel therapeutic targets to cure migraine. Keywords: migraine, bioinformatics, modeling and docking, KCNK18, TRESK, virtual screening, pharmacoinformatics

  3. New insight into p-glycoprotein as a drug target.

    Science.gov (United States)

    Breier, Albert; Gibalova, Lenka; Seres, Mario; Barancik, Miroslav; Sulova, Zdenka

    2013-01-01

    changes in cell sensitivity to substances that are not P-gp substrates or modulators. We recently reported that P-gppositive L1210 cells exhibit reduced sensitivity to cisplatin, concanavalin A, thapsigargin and tunicamycin. Thus, P-gp-mediated MDR represents a more complex process than was expected, and the unintended effects of P-gp overexpression should be considered when describing this phenotype. The present review aims to provide the most current informations about P-gp-mediated MDR while paying particular attention to the possible dual function of this protein as a drug efflux pump and a regulatory protein that influences diverse cell processes. From a clinical standpoint, overexpression of P-gp in cancer cells represents a real obstacle to effective chemotherapy for malignant diseases. Therefore, this protein should be considered as a viable target for pharmaceutical design. PMID:22931413

  4. Nanoscale Quantifying the Effects of Targeted Drug on Chemotherapy in Lymphoma Treatment Using Atomic Force Microscopy.

    Science.gov (United States)

    Li, Mi; Xiao, Xiubin; Liu, Lianqing; Xi, Ning; Wang, Yuechao

    2016-10-01

    The applications of targeted drugs in treating cancers have significantly improved the survival rates of patients. However, in the clinical practice, targeted drugs are commonly combined with chemotherapy drugs, causing that the exact contribution of targeted drugs to the clinical outcome is difficult to evaluate. Quantitatively investigating the effects of targeted drugs on chemotherapy drugs on cancer cells is useful for us to understand drug actions and design better drugs. The advent of atomic force microscopy (AFM) provides a powerful tool for probing the nanoscale physiological activities of single live cells. In this paper, the detailed changes in cell morphology and mechanical properties were quantified on single lymphoma cells during the actions of rituximab (a monoclonal antibody targeted drug) and two chemotherapy drugs (cisplatin and cytarabine) by AFM. AFM imaging revealed the distinct changes of cellular ultramicrostructures induced by the drugs. The changes of cellular mechanical properties after the drug stimulations were measured by AFM indenting. The statistical histograms of cellular surface roughness and mechanical properties quantitatively showed that rituximab could remarkably strengthen the killing effects of chemotherapy drugs. The study offers a new way to quantify the synergistic interactions between targeted drugs and chemotherapy drugs at the nanoscale, which will have potential impacts on predicting the efficacies of drug combinations before clinical treatments.

  5. Candidiasis drug discovery and development: new approaches targeting virulence for discovering and identifying new drugs

    Science.gov (United States)

    Pierce, Christopher G.; Lopez-Ribot, Jose L.

    2014-01-01

    Introduction Targeting pathogenetic mechanisms rather than essential processes represents a very attractive alternative for the development of new antibiotics. This may be particularly important in the case of antimycotics, due to the urgent need for novel antifungal drugs and the paucity of selective fungal targets. The opportunistic pathogenic fungus Candida albicans is the main etiological agent of candidiasis, the most common human fungal infection. These infections carry unacceptably high mortality rates, a clear reflection of the many shortcomings of current antifungal therapy, including the limited armamentarium of antifungal agents, their toxicity, and the emergence of resistance. Moreover the antifungal pipeline is mostly dry. Areas covered This review covers some of the most recent progress towards understanding C. albicans pathogenetic processes and how to harness this information for the development of anti-virulence agents. The two principal areas covered are filamentation and biofilm formation, as C. albicans pathogenicity is intimately linked to its ability to undergo morphogenetic conversions between yeast and filamentous morphologies and to its ability to form biofilms. Expert opinion We argue that filamentation and biofilm formation represent high value targets, yet clinically unexploited, for the development of novel anti-virulence approaches against candidiasis. Although this has proved a difficult task despite increasing understanding at the molecular level of C. albicans virulence, we highlight new opportunities and prospects for antifungal drug development targeting these two important biological processes. PMID:23738751

  6. RAS GTPase AS THE DRUG TARGET FOR ANTI-CANCER DESIGNING OF DRUG FROM TEMPLATE

    Directory of Open Access Journals (Sweden)

    A.S. Krishnapriya and P.K. Krishnan Namboori*

    2013-11-01

    Full Text Available Ras proteins in association with GTP and GDP act as a bio-molecular switch for signaling cell growth, cell survival and signal transduction. The presence of mutated Ras proteins is found to vary in different cancer types and the highest occurrence of about 90% is observed in pancreatic cancer. The Ras GTPase binding site is mainly involved in signal cell proliferation. Hence, this binding site has been considered as a major target. At the same time, targeting a specific protein and designing the drug molecule with respect to that is practically of no use as the target proteins are fast mutating. In this scenario, designing the template from the hot spot of proteins and fitting the template for all the target protein molecules seem to be a promising technique. The templates are initially screened on the basis of pharmacokinetic and pharmacodynamic requirements. Six templates are found to be satisfying conditions like IC50, lipophilic efficiency, ligand efficiency etc. and their efficiencies are compared with standard reference molecules. The computed enrichment factors support these templates to be leads for effective anti-cancer drugs subject to further in vitro and in vivo evaluation.

  7. Advanced drug delivery and targeting technologies for the ocular diseases

    Science.gov (United States)

    Barar, Jaleh; Aghanejad, Ayuob; Fathi, Marziyeh; Omidi, Yadollah

    2016-01-01

    Introduction: Ocular targeted therapy has enormously been advanced by implementation of new methods of drug delivery and targeting using implantable drug delivery systems (DDSs) or devices (DDDs), stimuli-responsive advanced biomaterials, multimodal nanomedicines, cell therapy modalities and medical bioMEMs. These technologies tackle several ocular diseases such as inflammation-based diseases (e.g., scleritis, keratitis, uveitis, iritis, conjunctivitis, chorioretinitis, choroiditis, retinitis, retinochoroiditis), ocular hypertension and neuropathy, age-related macular degeneration and mucopolysaccharidosis (MPS) due to accumulation of glycosaminoglycans (GAGs). Such therapies appear to provide ultimate treatments, even though much more effective, yet biocompatible, noninvasive therapies are needed to control some disabling ocular diseases/disorders. Methods: In the current study, we have reviewed and discussed recent advancements on ocular targeted therapies. Results: On the ground that the pharmacokinetic and pharmacodynamic analyses of ophthalmic drugs need special techniques, most of ocular DDSs/devices developments have been designed to localized therapy within the eye. Application of advanced DDSs such as Subconjunctival insert/implants (e.g., latanoprost implant, Gamunex-C), episcleral implant (e.g., LX201), cationic emulsions (e.g., Cationorm™, Vekacia™, Cyclokat™), intac/punctal plug DDSs (latanoprost punctal plug delivery system, L-PPDS), and intravitreal implants (I-vitaion™, NT-501, NT- 503, MicroPump, Thethadur, IB-20089 Verisome™, Cortiject, DE-102, Retisert™, Iluvein™ and Ozurdex™) have significantly improved the treatment of ocular diseases. However, most of these DDSs/devices are applied invasively and even need surgical procedures. Of these, use of de novo technologies such as advanced stimuli-responsive nanomaterials, multimodal nanosystems (NSs)/nanoconjugates (NCs), biomacromolecualr scaffolds, and bioengineered cell therapies

  8. Quantitative analysis on the characteristics of targets with FDA approved drugs

    Directory of Open Access Journals (Sweden)

    Meena K. Sakharkar, Peng Li, Zhaowei Zhong, Kishore R. Sakharkar

    2008-01-01

    Full Text Available Accumulated knowledge of genomic information, systems biology, and disease mechanisms provide an unprecedented opportunity to elucidate the genetic basis of diseases, and to discover new and novel therapeutic targets from the wealth of genomic data. With hundreds to a few thousand potential targets available in the human genome alone, target selection and validation has become a critical component of drug discovery process. The explorations on quantitative characteristics of the currently explored targets (those without any marketed drug and successful targets (targeted by at least one marketed drug could help discern simple rules for selecting a putative successful target. Here we use integrative in silico (computational approaches to quantitatively analyze the characteristics of 133 targets with FDA approved drugs and 3120 human disease genes (therapeutic targets not targeted by FDA approved drugs. This is the first attempt to comparatively analyze targets with FDA approved drugs and targets with no FDA approved drug or no drugs available for them. Our results show that proteins with 5 or fewer number of homologs outside their own family, proteins with single-exon gene architecture and proteins interacting with more than 3 partners are more likely to be targetable. These quantitative characteristics could serve as criteria to search for promising targetable disease genes.

  9. Autophagy modulation as a target for anticancer drug discovery

    Institute of Scientific and Technical Information of China (English)

    Xin LI; Huai-long XU; Yong-xi LIU; Na AN; Si ZHAO; Jin-ku BAO

    2013-01-01

    Autophagy,an evolutionarily conserved catabolic process involving the engulfment and degradation of non-essential or abnormal cellular organelles and proteins,is crucial for homeostatic maintenance in living cells.This highly regulated,multi-step process has been implicated in diverse diseases including cancer.Autophagy can function as either a promoter or a suppressor of cancer,which makes it a promising and challenging therapeutic target.Herein,we overview the regulatory mechanisms and dual roles of autophagy in cancer.We also describe some of the representative agents that exert their anticancer effects by regulating autophagy.Additionally,some emerging strategies aimed at modulating autophagy are discussed as having the potential for future anticancer drug discovery.In summary,these findings will provide valuable information to better utilize autophagy in the future development of anticancer therapeutics that meet clinical requirements.

  10. Adipokines as drug targets in diabetes and underlying disturbances.

    Science.gov (United States)

    Andrade-Oliveira, Vinícius; Câmara, Niels O S; Moraes-Vieira, Pedro M

    2015-01-01

    Diabetes and obesity are worldwide health problems. White fat dynamically participates in hormonal and inflammatory regulation. White adipose tissue is recognized as a multifactorial organ that secretes several adipose-derived factors that have been collectively termed "adipokines." Adipokines are pleiotropic molecules that gather factors such as leptin, adiponectin, visfatin, apelin, vaspin, hepcidin, RBP4, and inflammatory cytokines, including TNF and IL-1β, among others. Multiple roles in metabolic and inflammatory responses have been assigned to these molecules. Several adipokines contribute to the self-styled "low-grade inflammatory state" of obese and insulin-resistant subjects, inducing the accumulation of metabolic anomalies within these individuals, including autoimmune and inflammatory diseases. Thus, adipokines are an interesting drug target to treat autoimmune diseases, obesity, insulin resistance, and adipose tissue inflammation. The aim of this review is to present an overview of the roles of adipokines in different immune and nonimmune cells, which will contribute to diabetes as well as to adipose tissue inflammation and insulin resistance development. We describe how adipokines regulate inflammation in these diseases and their therapeutic implications. We also survey current attempts to exploit adipokines for clinical applications, which hold potential as novel approaches to drug development in several immune-mediated diseases.

  11. Discovery of the target for immunomodulatory drugs (IMiDs).

    Science.gov (United States)

    Ito, Takumi; Ando, Hideki; Handa, Hiroshi

    2016-05-01

    Half a century ago, the sedative thalidomide caused a serious drug disaster because of its teratogenicity and was withdrawn from the market. However, thalidomide, which has returned to the market, is now used for the treatment of leprosy and multiple myeloma (MM) under strict control. The mechanism of thalidomide action had been a long-standing question. We developed a new affinity bead technology and identified cereblon (CRBN) as a thalidomide-binding protein. We found that CRBN functions as a substrate receptor of an E3 cullin-Ring ligase complex 4 (CRL4) and is a primary target of thalidomide teratogenicity. Recently, new thalidomide derivatives, called immunomodulatory drugs (IMiDs), have been developed by Celgene. Among them, lenalidomide (Len) and pomalidomide (Pom) were shown to exert strong therapeutic effects against MM. It was found that Len and Pom both bind CRBN-CRL4 and recruit neomorphic substrates (Ikaros and Aiolos). More recently it was reported that casein kinase 1a (Ck1a) was identified as a substrate for CRBN-CRL4 in the presence of Len, but not Pom. Ck1a breakdown explains why Len is specifically effective for myelodysplastic syndrome with 5q deletion. It is now proposed that binding of IMiDs to CRBN appears to alter the substrate specificity of CRBN-CRL4. In this review, we introduce recent findings on IMiDs. PMID:27263779

  12. TRPV1: A Potential Drug Target for Treating Various Diseases

    Directory of Open Access Journals (Sweden)

    Rafael Brito

    2014-05-01

    Full Text Available Transient receptor potential vanilloid 1 (TRPV1 is an ion channel present on sensory neurons which is activated by heat, protons, capsaicin and a variety of endogenous lipids termed endovanilloids. As such, TRPV1 serves as a multimodal sensor of noxious stimuli which could trigger counteractive measures to avoid pain and injury. Activation of TRPV1 has been linked to chronic inflammatory pain conditions and peripheral neuropathy, as observed in diabetes. Expression of TRPV1 is also observed in non-neuronal sites such as the epithelium of bladder and lungs and in hair cells of the cochlea. At these sites, activation of TRPV1 has been implicated in the pathophysiology of diseases such as cystitis, asthma and hearing loss. Therefore, drugs which could modulate TRPV1 channel activity could be useful for the treatment of conditions ranging from chronic pain to hearing loss. This review describes the roles of TRPV1 in the normal physiology and pathophysiology of selected organs of the body and highlights how drugs targeting this channel could be important clinically.

  13. Discovery of the target for immunomodulatory drugs (IMiDs).

    Science.gov (United States)

    Ito, Takumi; Ando, Hideki; Handa, Hiroshi

    2016-05-01

    Half a century ago, the sedative thalidomide caused a serious drug disaster because of its teratogenicity and was withdrawn from the market. However, thalidomide, which has returned to the market, is now used for the treatment of leprosy and multiple myeloma (MM) under strict control. The mechanism of thalidomide action had been a long-standing question. We developed a new affinity bead technology and identified cereblon (CRBN) as a thalidomide-binding protein. We found that CRBN functions as a substrate receptor of an E3 cullin-Ring ligase complex 4 (CRL4) and is a primary target of thalidomide teratogenicity. Recently, new thalidomide derivatives, called immunomodulatory drugs (IMiDs), have been developed by Celgene. Among them, lenalidomide (Len) and pomalidomide (Pom) were shown to exert strong therapeutic effects against MM. It was found that Len and Pom both bind CRBN-CRL4 and recruit neomorphic substrates (Ikaros and Aiolos). More recently it was reported that casein kinase 1a (Ck1a) was identified as a substrate for CRBN-CRL4 in the presence of Len, but not Pom. Ck1a breakdown explains why Len is specifically effective for myelodysplastic syndrome with 5q deletion. It is now proposed that binding of IMiDs to CRBN appears to alter the substrate specificity of CRBN-CRL4. In this review, we introduce recent findings on IMiDs.

  14. Structures of Trypanosome Vacuolar Soluble Pyrophosphatases: Antiparasitic Drug Targets.

    Science.gov (United States)

    Yang, Yunyun; Ko, Tzu-Ping; Chen, Chun-Chi; Huang, Guozhong; Zheng, Yingying; Liu, Weidong; Wang, Iren; Ho, Meng-Ru; Hsu, Shang-Te Danny; O'Dowd, Bing; Huff, Hannah C; Huang, Chun-Hsiang; Docampo, Roberto; Oldfield, Eric; Guo, Rey-Ting

    2016-05-20

    Trypanosomatid parasites are the causative agents of many neglected tropical diseases, including the leishmaniases, Chagas disease, and human African trypanosomiasis. They exploit unusual vacuolar soluble pyrophosphatases (VSPs), absent in humans, for cell growth and virulence and, as such, are drug targets. Here, we report the crystal structures of VSP1s from Trypanosoma cruzi and T. brucei, together with that of the T. cruzi protein bound to a bisphosphonate inhibitor. Both VSP1s form a hybrid structure containing an (N-terminal) EF-hand domain fused to a (C-terminal) pyrophosphatase domain. The two domains are connected via an extended loop of about 17 residues. Crystallographic analysis and size exclusion chromatography indicate that the VSP1s form tetramers containing head-to-tail dimers. Phosphate and diphosphate ligands bind in the PPase substrate-binding pocket and interact with several conserved residues, and a bisphosphonate inhibitor (BPH-1260) binds to the same site. On the basis of Cytoscape and other bioinformatics analyses, it is apparent that similar folds will be found in most if not all trypanosomatid VSP1s, including those found in insects (Angomonas deanei, Strigomonas culicis), plant pathogens (Phytomonas spp.), and Leishmania spp. Overall, the results are of general interest since they open the way to structure-based drug design for many of the neglected tropical diseases. PMID:26907161

  15. Are Pharmaceuticals with Evolutionary Conserved Molecular Drug Targets More Potent to Cause Toxic Effects in Non-Target Organisms?

    OpenAIRE

    Sara Furuhagen; Anne Fuchs; Elin Lundström Belleza; Magnus Breitholtz; Elena Gorokhova

    2014-01-01

    The ubiquitous use of pharmaceuticals has resulted in a continuous discharge into wastewater and pharmaceuticals and their metabolites are found in the environment. Due to their design towards specific drug targets, pharmaceuticals may be therapeutically active already at low environmental concentrations. Several human drug targets are evolutionary conserved in aquatic organisms, raising concerns about effects of these pharmaceuticals in non-target organisms. In this study, we hypothesized th...

  16. Optimized shapes of magnetic arrays for drug targeting applications

    Science.gov (United States)

    Barnsley, Lester C.; Carugo, Dario; Stride, Eleanor

    2016-06-01

    Arrays of permanent magnet elements have been utilized as light-weight, inexpensive sources for applying external magnetic fields in magnetic drug targeting applications, but they are extremely limited in the range of depths over which they can apply useful magnetic forces. In this paper, designs for optimized magnet arrays are presented, which were generated using an optimization routine to maximize the magnetic force available from an arbitrary arrangement of magnetized elements, depending on a set of design parameters including the depth of targeting (up to 50 mm from the magnet) and direction of force required. A method for assembling arrays in practice is considered, quantifying the difficulty of assembly and suggesting a means for easing this difficulty without a significant compromise to the applied field or force. Finite element simulations of in vitro magnetic retention experiments were run to demonstrate the capability of a subset of arrays to retain magnetic microparticles against flow. The results suggest that, depending on the choice of array, a useful proportion of particles (more than 10% ) could be retained at flow velocities up to 100 mm s-1 or to depths as far as 50 mm from the magnet. Finally, the optimization routine was used to generate a design for a Halbach array optimized to deliver magnetic force to a depth of 50 mm inside the brain.

  17. Leptin signaling molecular actions and drug target in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Jiang N

    2014-11-01

    leptin and Ob-R in cancer cells compared to normal cells, makes leptin an ideal drug target for the prevention and treatment of HCC, especially in obese patients. Keywords: hepatocellular carcinoma, leptin, leptin antagonist, leptin signaling, tumor angiogenesis, drug target

  18. Intrinsically Unstructured Proteins: Potential Targets for Drug Discovery

    Directory of Open Access Journals (Sweden)

    Pathan Salma

    2009-01-01

    Full Text Available Problem statement: The function of a protein is dependent on its three-dimensional structure. However, numerous proteins lacking intrinsic globular 3D structure under physiological conditions had been recognized. These proteins are frequently involved in some of the most critical cellular control mechanisms and it appears that their rapid turnover, aided by their unstructured nature in the unbound state, provides a level of control that allows rapid and accurate responses of the cell to changing environmental conditions. Approach: A significant number of proteins known to be involved in protein deposition disorders were now considered to Be Intrinsically Unstructured Proteins (IUPs. For example, Aß peptide and tau protein in Alzheimer’s disease, PrP in Prion’s disease and a-Synuclein in Parkinson’s disease. The disorder of intrinsically unstructured proteins (IUP's was crucial to their functions. They may adopt defined but extended structures when bound to cognate ligands. Their amino acid compositions were less hydrophobic than those of soluble proteins. They lack hydrophobic cores and hence did not become insoluble when heated. About 40% of eukaryotic proteins had at least one long (>50 residues disordered region. Roughly 10% of proteins in various genomes had been predicted to be fully disordered. Presently over 100 IUP's had been identified; none are enzymes. Obviously, IUP's were greatly underrepresented in the Protein Data Bank, although there were few cases of an IUP bound to a folded (intrinsically structured protein. Results: The five functional categories for intrinsically unstructured proteins and domains were entropic chains (bristles to ensure spacing, springs, flexible spacers/linkers, effectors (inhibitors and disassemblers, scavengers, assemblers and display sites. These IUPs could serve as potential targets for Structure Based Drug Design (SBDD which stress on the transition

  19. Dendrimers in drug delivery and targeting: Drug-dendrimer interactions and toxicity issues

    Directory of Open Access Journals (Sweden)

    Kanika Madaan

    2014-01-01

    Full Text Available Dendrimers are the emerging polymeric architectures that are known for their defined structures, versatility in drug delivery and high functionality whose properties resemble with biomolecules. These nanostructured macromolecules have shown their potential abilities in entrapping and/or conjugating the high molecular weight hydrophilic/hydrophobic entities by host-guest interactions and covalent bonding (prodrug approach respectively. Moreover, high ratio of surface groups to molecular volume has made them a promising synthetic vector for gene delivery. Owing to these properties dendrimers have fascinated the researchers in the development of new drug carriers and they have been implicated in many therapeutic and biomedical applications. Despite of their extensive applications, their use in biological systems is limited due to toxicity issues associated with them. Considering this, the present review has focused on the different strategies of their synthesis, drug delivery and targeting, gene delivery and other biomedical applications, interactions involved in formation of drug-dendrimer complex along with characterization techniques employed for their evaluation, toxicity problems and associated approaches to alleviate their inherent toxicity.

  20. Orexin Receptor Targets for Anti-Relapse Medication Development in Drug Addiction

    OpenAIRE

    See, Ronald E.; Luyi Zhou; Wei-Lun Sun

    2011-01-01

    Drug addiction is a chronic illness characterized by high rates of relapse. Relapse to drug use can be triggered by re-exposure to drug-associated cues, stressful events, or the drug itself after a period of abstinence. Pharmacological intervention to reduce the impact of relapse-instigating factors offers a promising target for addiction treatment. Growing evidence has implicated an important role of the orexin/hypocretin system in drug reward and drug-seeking, including animal models of rel...

  1. Polymeric particulate technologies for oral drug delivery and targeting: A pathophysiological perspective

    DEFF Research Database (Denmark)

    Hunter, A. Christy; Elsom, Jacqueline; Wibroe, Peter Popp;

    2012-01-01

    to optimize drug targeting and bioavailability. Frequently the carrier systems used are either constructed from or contain polymeric materials. Examples of these nanocarriers include polymeric nanoparticles, solid lipid nanocarriers, self-nanoemulsifying drug delivery systems and nanocrystals...

  2. A comprehensive assessment of lymphatic filariasis in Sri Lanka six years after cessation of mass drug administration.

    Directory of Open Access Journals (Sweden)

    Ramakrishna U Rao

    Full Text Available The Sri Lankan Anti-Filariasis Campaign conducted 5 rounds of mass drug administration (MDA with diethycarbamazine plus albendazole between 2002 and 2006. We now report results of a comprehensive surveillance program that assessed the lymphatic filariasis (LF situation in Sri Lanka 6 years after cessation of MDA.Transmission assessment surveys (TAS were performed per WHO guidelines in primary school children in 11 evaluation units (EUs in all 8 formerly endemic districts. All EUs easily satisfied WHO criteria for stopping MDA. Comprehensive surveillance was performed in 19 Public Health Inspector (PHI areas (subdistrict health administrative units. The surveillance package included cross-sectional community surveys for microfilaremia (Mf and circulating filarial antigenemia (CFA, school surveys for CFA and anti-filarial antibodies, and collection of Culex mosquitoes with gravid traps for detection of filarial DNA (molecular xenomonitoring, MX. Provisional target rates for interruption of LF transmission were community CFA <2%, antibody in school children <2%, and filarial DNA in mosquitoes <0.25%. Community Mf and CFA prevalence rates ranged from 0-0.9% and 0-3.4%, respectively. Infection rates were significantly higher in males and lower in people who denied prior treatment. Antibody rates in school children exceeded 2% in 10 study sites; the area that had the highest community and school CFA rates also had the highest school antibody rate (6.9%. Filarial DNA rates in mosquitoes exceeded 0.25% in 10 PHI areas.Comprehensive surveillance is feasible for some national filariasis elimination programs. Low-level persistence of LF was present in all study sites; several sites failed to meet provisional endpoint criteria for LF elimination, and follow-up testing will be needed in these areas. TAS was not sensitive for detecting low-level persistence of filariasis in Sri Lanka. We recommend use of antibody and MX testing as tools to complement TAS for

  3. A Comprehensive Assessment of Lymphatic Filariasis in Sri Lanka Six Years after Cessation of Mass Drug Administration

    Science.gov (United States)

    Rao, Ramakrishna U.; Nagodavithana, Kumara C.; Samarasekera, Sandhya D.; Wijegunawardana, Asha D.; Premakumara, Welmillage D. Y.; Perera, Samudrika N.; Settinayake, Sunil; Miller, J. Phillip; Weil, Gary J.

    2014-01-01

    Background The Sri Lankan Anti-Filariasis Campaign conducted 5 rounds of mass drug administration (MDA) with diethycarbamazine plus albendazole between 2002 and 2006. We now report results of a comprehensive surveillance program that assessed the lymphatic filariasis (LF) situation in Sri Lanka 6 years after cessation of MDA. Methodology and Principal Findings Transmission assessment surveys (TAS) were performed per WHO guidelines in primary school children in 11 evaluation units (EUs) in all 8 formerly endemic districts. All EUs easily satisfied WHO criteria for stopping MDA. Comprehensive surveillance was performed in 19 Public Health Inspector (PHI) areas (subdistrict health administrative units). The surveillance package included cross-sectional community surveys for microfilaremia (Mf) and circulating filarial antigenemia (CFA), school surveys for CFA and anti-filarial antibodies, and collection of Culex mosquitoes with gravid traps for detection of filarial DNA (molecular xenomonitoring, MX). Provisional target rates for interruption of LF transmission were community CFA <2%, antibody in school children <2%, and filarial DNA in mosquitoes <0.25%. Community Mf and CFA prevalence rates ranged from 0–0.9% and 0–3.4%, respectively. Infection rates were significantly higher in males and lower in people who denied prior treatment. Antibody rates in school children exceeded 2% in 10 study sites; the area that had the highest community and school CFA rates also had the highest school antibody rate (6.9%). Filarial DNA rates in mosquitoes exceeded 0.25% in 10 PHI areas. Conclusions Comprehensive surveillance is feasible for some national filariasis elimination programs. Low-level persistence of LF was present in all study sites; several sites failed to meet provisional endpoint criteria for LF elimination, and follow-up testing will be needed in these areas. TAS was not sensitive for detecting low-level persistence of filariasis in Sri Lanka. We recommend use of

  4. Serine Proteases of Malaria Parasite Plasmodium falciparum: Potential as Antimalarial Drug Targets

    OpenAIRE

    Asrar Alam

    2014-01-01

    Malaria is a major global parasitic disease and a cause of enormous mortality and morbidity. Widespread drug resistance against currently available antimalarials warrants the identification of novel drug targets and development of new drugs. Malarial proteases are a group of molecules that serve as potential drug targets because of their essentiality for parasite life cycle stages and feasibility of designing specific inhibitors against them. Proteases belonging to various mechanistic classes...

  5. The antihelmintic drug pyrvinium pamoate targets aggressive breast cancer.

    Directory of Open Access Journals (Sweden)

    Wei Xu

    Full Text Available WNT signaling plays a key role in the self-renewal of tumor initiation cells (TICs. In this study, we used pyrvinium pamoate (PP, an FDA-approved antihelmintic drug that inhibits WNT signaling, to test whether pharmacologic inhibition of WNT signaling can specifically target TICs of aggressive breast cancer cells. SUM-149, an inflammatory breast cancer cell line, and SUM-159, a metaplastic basal-type breast cancer cell line, were used in these studies. We found that PP inhibited primary and secondary mammosphere formation of cancer cells at nanomolar concentrations, at least 10 times less than the dose needed to have a toxic effect on cancer cells. A comparable mammosphere formation IC50 dose to that observed in cancer cell lines was obtained using malignant pleural effusion samples from patients with IBC. A decrease in activity of the TIC surrogate aldehyde dehydrogenase was observed in PP-treated cells, and inhibition of WNT signaling by PP was associated with down-regulation of a panel of markers associated with epithelial-mesenchymal transition. In vivo, intratumoral injection was associated with tumor necrosis, and intraperitoneal injection into mice with tumor xenografts caused significant tumor growth delay and a trend toward decreased lung metastasis. In in vitro mammosphere-based and monolayer-based clonogenic assays, we found that PP radiosensitized cells in monolayer culture but not mammosphere culture. These findings suggest WNT signaling inhibition may be a feasible strategy for targeting aggressive breast cancer. Investigation and modification of the bioavailability and toxicity profile of systemic PP are warranted.

  6. Legionella pneumophila Carbonic Anhydrases: Underexplored Antibacterial Drug Targets.

    Science.gov (United States)

    Supuran, Claudiu T

    2016-01-01

    Carbonic anhydrases (CAs, EC 4.2.1.1) are metalloenzymes which catalyze the hydration of carbon dioxide to bicarbonate and protons. Many pathogenic bacteria encode such enzymes belonging to the α-, β-, and/or γ-CA families. In the last decade, enzymes from some of these pathogens, including Legionella pneumophila, have been cloned and characterized in detail. These enzymes were shown to be efficient catalysts for CO₂ hydration, with kcat values in the range of (3.4-8.3) × 10⁵ s(-1) and kcat/KM values of (4.7-8.5) × 10⁷ M(-1)·s(-1). In vitro inhibition studies with various classes of inhibitors, such as anions, sulfonamides and sulfamates, were also reported for the two β-CAs from this pathogen, LpCA1 and LpCA2. Inorganic anions were millimolar inhibitors, whereas diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid, and phenylarsonic acid were micromolar ones. The best LpCA1 inhibitors were aminobenzolamide and structurally similar sulfonylated aromatic sulfonamides, as well as acetazolamide and ethoxzolamide (KIs in the range of 40.3-90.5 nM). The best LpCA2 inhibitors belonged to the same class of sulfonylated sulfonamides, together with acetazolamide, methazolamide, and dichlorophenamide (KIs in the range of 25.2-88.5 nM). Considering such preliminary results, the two bacterial CAs from this pathogen represent promising yet underexplored targets for obtaining antibacterials devoid of the resistance problems common to most of the clinically used antibiotics, but further studies are needed to validate them in vivo as drug targets. PMID:27322334

  7. Legionella pneumophila Carbonic Anhydrases: Underexplored Antibacterial Drug Targets

    Directory of Open Access Journals (Sweden)

    Claudiu T. Supuran

    2016-06-01

    Full Text Available Carbonic anhydrases (CAs, EC 4.2.1.1 are metalloenzymes which catalyze the hydration of carbon dioxide to bicarbonate and protons. Many pathogenic bacteria encode such enzymes belonging to the α-, β-, and/or γ-CA families. In the last decade, enzymes from some of these pathogens, including Legionella pneumophila, have been cloned and characterized in detail. These enzymes were shown to be efficient catalysts for CO2 hydration, with kcat values in the range of (3.4–8.3 × 105 s−1 and kcat/KM values of (4.7–8.5 × 107 M−1·s−1. In vitro inhibition studies with various classes of inhibitors, such as anions, sulfonamides and sulfamates, were also reported for the two β-CAs from this pathogen, LpCA1 and LpCA2. Inorganic anions were millimolar inhibitors, whereas diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid, and phenylarsonic acid were micromolar ones. The best LpCA1 inhibitors were aminobenzolamide and structurally similar sulfonylated aromatic sulfonamides, as well as acetazolamide and ethoxzolamide (KIs in the range of 40.3–90.5 nM. The best LpCA2 inhibitors belonged to the same class of sulfonylated sulfonamides, together with acetazolamide, methazolamide, and dichlorophenamide (KIs in the range of 25.2–88.5 nM. Considering such preliminary results, the two bacterial CAs from this pathogen represent promising yet underexplored targets for obtaining antibacterials devoid of the resistance problems common to most of the clinically used antibiotics, but further studies are needed to validate them in vivo as drug targets.

  8. RGD-modified lipid disks as drug carriers for tumor targeted drug delivery

    Science.gov (United States)

    Gao, Jie; Xie, Cao; Zhang, Mingfei; Wei, Xiaoli; Yan, Zhiqiang; Ren, Yachao; Ying, Man; Lu, Weiyue

    2016-03-01

    Melittin, the major component of the European bee venom, is a potential anticancer candidate due to its lytic properties. However, in vivo applications of melittin are limited due to its main side effect, hemolysis, especially when applied through intravenous administration. The polyethylene glycol-stabilized lipid disk is a novel type of nanocarrier, and the rim of lipid disks has a high affinity to amphiphilic peptides. In our study, a c(RGDyK) modified lipid disk was developed as a tumor targeted drug delivery system for melittin. Cryo-TEM was used to confirm the shape and size of lipid disks with or without c(RGDyK) modification. In vitro and in vivo hemolysis analyses revealed that the hemolysis effect significantly decreased after melittin associated with lipid disks. Importantly, the results of our in vivo biodistribution and tumor growth inhibitory experiments showed that c(RGDyK) modification increased the distribution of lipid disks in the tumor and the anticancer efficacy of melittin loaded lipid disks. Thus, we successfully achieved a targeted drug delivery system for melittin and other amphiphilic peptides with a good therapeutic effect and low side effects.

  9. Targeted lipid based drug conjugates: a novel strategy for drug delivery.

    Science.gov (United States)

    Vadlapudi, Aswani Dutt; Vadlapatla, Ramya Krishna; Kwatra, Deep; Earla, Ravinder; Samanta, Swapan K; Pal, Dhananjay; Mitra, Ashim K

    2012-09-15

    A majority of studies involving prodrugs are directed to overcome low bioavailability of the parent drug. The aim of this study is to increase the bioavailability of acyclovir (ACV) by designing a novel prodrug delivery system which is more lipophilic, and at the same time site specific. In this study, a lipid raft has been conjugated to the parent drug molecule to impart lipophilicity. Simultaneously a targeting moiety that can be recognized by a specific transporter/receptor in the cell membrane has also been tethered to the other terminal of lipid raft. Targeted lipid prodrugs i.e., biotin-ricinoleicacid-acyclovir (B-R-ACV) and biotin-12hydroxystearicacid-acyclovir (B-12HS-ACV) were synthesized with ricinoleicacid and 12hydroxystearicacid as the lipophilic rafts and biotin as the targeting moiety. Biotin-ACV (B-ACV), ricinoleicacid-ACV (R-ACV) and 12hydroxystearicacid-ACV (12HS-ACV) were also synthesized to delineate the individual effects of the targeting and the lipid moieties. Cellular accumulation studies were performed in confluent MDCK-MDR1 and Caco-2 cells. The targeted lipid prodrugs B-R-ACV and B-12HS-ACV exhibited much higher cellular accumulation than B-ACV, R-ACV and 12HS-ACV in both cell lines. This result indicates that both the targeting and the lipid moiety act synergistically toward cellular uptake. The biotin conjugated prodrugs caused a decrease in the uptake of [(3)H] biotin suggesting the role of sodium dependent multivitamin transporter (SMVT) in uptake. The affinity of these targeted lipid prodrugs toward SMVT was studied in MDCK-MDR1 cells. Both the targeted lipid prodrugs B-R-ACV (20.25 ± 1.74 μM) and B-12HS-ACV (23.99 ± 3.20 μM) demonstrated higher affinity towards SMVT than B-ACV (30.90 ± 4.19 μM). Further, dose dependent studies revealed a concentration dependent inhibitory effect on [(3)H] biotin uptake in the presence of biotinylated prodrugs. Transepithelial transport studies showed lowering of [(3)H] biotin permeability in

  10. The drug-target residence time model: a 10-year retrospective.

    Science.gov (United States)

    Copeland, Robert A

    2016-02-01

    The drug-target residence time model was first introduced in 2006 and has been broadly adopted across the chemical biology, biotechnology and pharmaceutical communities. While traditional in vitro methods view drug-target interactions exclusively in terms of equilibrium affinity, the residence time model takes into account the conformational dynamics of target macromolecules that affect drug binding and dissociation. The key tenet of this model is that the lifetime (or residence time) of the binary drug-target complex, and not the binding affinity per se, dictates much of the in vivo pharmacological activity. Here, this model is revisited and key applications of it over the past 10 years are highlighted.

  11. Enzymology of the nematode cuticle: A potential drug target?

    Science.gov (United States)

    Page, Antony P; Stepek, Gillian; Winter, Alan D; Pertab, David

    2014-08-01

    All nematodes possess an external structure known as the cuticle, which is crucial for their development and survival. This structure is composed primarily of collagen, which is secreted from the underlying hypodermal cells. Extensive studies using the free-living nematode Caenorhabditis elegans demonstrate that formation of the cuticle requires the activity of an extensive range of enzymes. Enzymes are required both pre-secretion, for synthesis of component proteins such as collagen, and post-secretion, for removal of the previous developmental stage cuticle, in a process known as moulting or exsheathment. The excretion/secretion products of numerous parasitic nematodes contain metallo-, serine and cysteine proteases, and these proteases are conserved across the nematode phylum and many are involved in the moulting/exsheathment process. This review highlights the enzymes required for cuticle formation, with a focus on the post-secretion moulting events. Where orthologues of the C. elegans enzymes have been identified in parasitic nematodes these may represent novel candidate targets for future drug/vaccine development. PMID:25057463

  12. Neuropeptides as targets for the development of anticonvulsant drugs.

    Science.gov (United States)

    Clynen, Elke; Swijsen, Ann; Raijmakers, Marjolein; Hoogland, Govert; Rigo, Jean-Michel

    2014-10-01

    Epilepsy is a common neurological disorder characterized by recurrent seizures. These seizures are due to abnormal excessive and synchronous neuronal activity in the brain caused by a disruption of the delicate balance between excitation and inhibition. Neuropeptides can contribute to such misbalance by modulating the effect of classical excitatory and inhibitory neurotransmitters. In this review, we discuss 21 different neuropeptides that have been linked to seizure disorders. These neuropeptides show an aberrant expression and/or release in animal seizure models and/or epilepsy patients. Many of these endogenous peptides, like adrenocorticotropic hormone, angiotensin, cholecystokinin, cortistatin, dynorphin, galanin, ghrelin, neuropeptide Y, neurotensin, somatostatin, and thyrotropin-releasing hormone, are able to suppress seizures in the brain. Other neuropeptides, such as arginine-vasopressine peptide, corticotropin-releasing hormone, enkephalin, β-endorphin, pituitary adenylate cyclase-activating polypeptide, and tachykinins have proconvulsive properties. For oxytocin and melanin-concentrating hormone both pro- and anticonvulsive effects have been reported, and this seems to be dose or time dependent. All these neuropeptides and their receptors are interesting targets for the development of new antiepileptic drugs. Other neuropeptides such as nesfatin-1 and vasoactive intestinal peptide have been less studied in this field; however, as nesfatin-1 levels change over the course of epilepsy, this can be considered as an interesting marker to diagnose patients who have suffered a recent epileptic seizure.

  13. A small molecule nanodrug consisting of amphiphilic targeting ligand-chemotherapy drug conjugate for targeted cancer therapy.

    Science.gov (United States)

    Mou, Quanbing; Ma, Yuan; Zhu, Xinyuan; Yan, Deyue

    2016-05-28

    Targeted drug delivery is a broadly applicable approach for cancer therapy. However, the nanocarrier-based targeted delivery system suffers from batch-to-batch variation, quality concerns and carrier-related toxicity issues. Thus, to develop a carrier-free targeted delivery system with nanoscale characteristics is very attractive. Here, a novel targeting small molecule nanodrug self-delivery system consisting of targeting ligand and chemotherapy drug was constructed, which combined the advantages of small molecules and nano-assemblies together and showed excellent targeting ability and long blood circulation time with well-defined structure, high drug loading ratio and on-demand drug release behavior. As a proof-of-concept, lactose (Lac) and doxorubicin (DOX) were chosen as the targeting ligand and chemotherapy drug, respectively. Lac and DOX were conjugated through a pH-responsive hydrazone group. For its intrinsic amphiphilic property, Lac-DOX conjugate could self-assemble into nanoparticles in water. Both in vitro and in vivo assays indicated that Lac-DOX nanoparticles exhibited enhanced anticancer activity and weak side effects. This novel active targeting nanodrug delivery system shows great potential in cancer therapy. PMID:27040815

  14. Drug target mining and analysis of the Chinese tree shrew for pharmacological testing.

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    Full Text Available The discovery of new drugs requires the development of improved animal models for drug testing. The Chinese tree shrew is considered to be a realistic candidate model. To assess the potential of the Chinese tree shrew for pharmacological testing, we performed drug target prediction and analysis on genomic and transcriptomic scales. Using our pipeline, 3,482 proteins were predicted to be drug targets. Of these predicted targets, 446 and 1,049 proteins with the highest rank and total scores, respectively, included homologs of targets for cancer chemotherapy, depression, age-related decline and cardiovascular disease. Based on comparative analyses, more than half of drug target proteins identified from the tree shrew genome were shown to be higher similarity to human targets than in the mouse. Target validation also demonstrated that the constitutive expression of the proteinase-activated receptors of tree shrew platelets is similar to that of human platelets but differs from that of mouse platelets. We developed an effective pipeline and search strategy for drug target prediction and the evaluation of model-based target identification for drug testing. This work provides useful information for future studies of the Chinese tree shrew as a source of novel targets for drug discovery research.

  15. Identifying the Right Disease Targets to Develop Better Drugs, Faster | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... this page please turn JavaScript on. Identifying the Right Disease Targets to Develop Better Drugs, Faster Past ... reason is that we're not selecting the right biological changes to target from the start. How ...

  16. Micro RNA, A Review: Pharmacogenomic drug targets for complex diseases

    Directory of Open Access Journals (Sweden)

    Sandhya Bawa

    2010-01-01

    Full Text Available

    Micro RNAs (miRNAs are non-coding RNAs that can regulate gene expression to target several mRNAs in a gene regulatory network. MiRNA related Single Nucleotide Polymorphisms (S.N.P.s represent a newly identified type of genetic variability that can be of influence to the risk of certain human diseases and also affect how drugs can be activated and metabolized by patients. This will help in personalized medicines which are used for administrating the correct dosage of drug and drug efficacy. miRNA deregulated expression has been extensively described in a variety of diseases such as Cancer, Obesity , Diabetes, Schizophrenia and control and self renewal of stem cells. MiRNA can function as oncogenes and/or tumor suppressors. MiRNAs may act as key regulators of processes as diverse as early development, cell proliferation and cell death, apoptosis and fat metabolism and cell differentiation .miRNA expression have shown their role in brain development chronic lymphocytic leukemia, colonic adeno carcinoma, Burkiff’s lymphoma and viral infection. These show their links with viral disease, neurodevelopment and cancer. It has been shown that they play a key role in melanoma metastasis. These may be

  17. iDrug-Target: predicting the interactions between drug compounds and target proteins in cellular networking via benchmark dataset optimization approach.

    Science.gov (United States)

    Xiao, Xuan; Min, Jian-Liang; Lin, Wei-Zhong; Liu, Zi; Cheng, Xiang; Chou, Kuo-Chen

    2015-01-01

    Information about the interactions of drug compounds with proteins in cellular networking is very important for drug development. Unfortunately, all the existing predictors for identifying drug-protein interactions were trained by a skewed benchmark data-set where the number of non-interactive drug-protein pairs is overwhelmingly larger than that of the interactive ones. Using this kind of highly unbalanced benchmark data-set to train predictors would lead to the outcome that many interactive drug-protein pairs might be mispredicted as non-interactive. Since the minority interactive pairs often contain the most important information for drug design, it is necessary to minimize this kind of misprediction. In this study, we adopted the neighborhood cleaning rule and synthetic minority over-sampling technique to treat the skewed benchmark datasets and balance the positive and negative subsets. The new benchmark datasets thus obtained are called the optimized benchmark datasets, based on which a new predictor called iDrug-Target was developed that contains four sub-predictors: iDrug-GPCR, iDrug-Chl, iDrug-Ezy, and iDrug-NR, specialized for identifying the interactions of drug compounds with GPCRs (G-protein-coupled receptors), ion channels, enzymes, and NR (nuclear receptors), respectively. Rigorous cross-validations on a set of experiment-confirmed datasets have indicated that these new predictors remarkably outperformed the existing ones for the same purpose. To maximize users' convenience, a public accessible Web server for iDrug-Target has been established at http://www.jci-bioinfo.cn/iDrug-Target/ , by which users can easily get their desired results. It has not escaped our notice that the aforementioned strategy can be widely used in many other areas as well.

  18. Tetrahydrobiopterin Biosynthesis as an Off-Target of Sulfa Drugs

    OpenAIRE

    Haruki, H.; Pedersen, M.G.; Gorska, K. I.; Pojer, F.; Johnsson, K.

    2013-01-01

    The introduction of sulfa drugs for the chemotherapy of bacterial infections in 1935 revolutionized medicine. Although their mechanism of action is understood, the molecular bases for most of their side effects remain obscure. Here, we report that sulfamethoxazole and other sulfa drugs interfere with tetrahydrobiopterin biosynthesis through inhibition of sepiapterin reductase. Crystal structures of sepiapterin reductase with bound sulfa drugs reveal how structurally diverse sulfa drugs achiev...

  19. Thiamin (Vitamin B1 Biosynthesis and Regulation: A Rich Source of Antimicrobial Drug Targets?

    Directory of Open Access Journals (Sweden)

    Qinglin Du, Honghai Wang, Jianping Xie

    2011-01-01

    Full Text Available Drug resistance of pathogens has necessitated the identification of novel targets for antibiotics. Thiamin (vitamin B1 is an essential cofactor for all organisms in its active form thiamin diphosphate (ThDP. Therefore, its metabolic pathways might be one largely untapped source of antibiotics targets. This review describes bacterial thiamin biosynthetic, salvage, and transport pathways. Essential thiamin synthetic enzymes such as Dxs and ThiE are proposed as promising drug targets. The regulation mechanism of thiamin biosynthesis by ThDP riboswitch is also discussed. As drug targets of existing antimicrobial compound pyrithiamin, the ThDP riboswitch might serves as alternative targets for more antibiotics.

  20. Sterol Biosynthesis Pathway as Target for Anti-trypanosomatid Drugs

    Directory of Open Access Journals (Sweden)

    Wanderley de Souza

    2009-01-01

    Full Text Available Sterols are constituents of the cellular membranes that are essential for their normal structure and function. In mammalian cells, cholesterol is the main sterol found in the various membranes. However, other sterols predominate in eukaryotic microorganisms such as fungi and protozoa. It is now well established that an important metabolic pathway in fungi and in members of the Trypanosomatidae family is one that produces a special class of sterols, including ergosterol, and other 24-methyl sterols, which are required for parasitic growth and viability, but are absent from mammalian host cells. Currently, there are several drugs that interfere with sterol biosynthesis (SB that are in use to treat diseases such as high cholesterol in humans and fungal infections. In this review, we analyze the effects of drugs such as (a statins, which act on the mevalonate pathway by inhibiting HMG-CoA reductase, (b bisphosphonates, which interfere with the isoprenoid pathway in the step catalyzed by farnesyl diphosphate synthase, (c zaragozic acids and quinuclidines, inhibitors of squalene synthase (SQS, which catalyzes the first committed step in sterol biosynthesis, (d allylamines, inhibitors of squalene epoxidase, (e azoles, which inhibit C14α-demethylase, and (f azasterols, which inhibit Δ24(25-sterol methyltransferase (SMT. Inhibition of this last step appears to have high selectivity for fungi and trypanosomatids, since this enzyme is not found in mammalian cells. We review here the IC50 values of these various inhibitors, their effects on the growth of trypanosomatids (both in axenic cultures and in cell cultures, and their effects on protozoan structural organization (as evaluted by light and electron microscopy and lipid composition. The results show that the mitochondrial membrane as well as the membrane lining the protozoan cell body and flagellum are the main targets. Probably as a consequence of these primary effects, other important changes take

    1. ORAL COLON TARGETED DRUG DELIVERY SYSTEM: A REVIEW ON CURRENT AND NOVEL PERSPECTIVES

      Directory of Open Access Journals (Sweden)

      Asija Rajesh

      2012-10-01

      Full Text Available Small intestine is mostly the site for drug absorption but in some cases the drug needs to be targeted to colon due to some factors like local colonic disease, degradation related conditions, delayed release of drugs, systemic delivery of protein and peptide drugs etc. Colon targeted drug delivery is important and relatively new concept for the absorption of drugs because it offers almost neutral pH and long residence time, thereby increasing the drug absorption. Colon has proved to be a site for the absorption of poorly soluble drugs. For the successful targeting of drugs to colon the dosage form should be designed such that it prevents the drug release in upper GIT and releasing it in the colonic region. This review article discusses in brief about introduction of colon along with the novel and emerging technologies for colon targeting of drug molecule. Treatment of these diseases with colon-specific drug delivery system provides an interesting alternative over systemic drug administration because of lower dosing and fewer systemic side effects.

    2. Are pharmaceuticals with evolutionary conserved molecular drug targets more potent to cause toxic effects in non-target organisms?

      Directory of Open Access Journals (Sweden)

      Sara Furuhagen

      Full Text Available The ubiquitous use of pharmaceuticals has resulted in a continuous discharge into wastewater and pharmaceuticals and their metabolites are found in the environment. Due to their design towards specific drug targets, pharmaceuticals may be therapeutically active already at low environmental concentrations. Several human drug targets are evolutionary conserved in aquatic organisms, raising concerns about effects of these pharmaceuticals in non-target organisms. In this study, we hypothesized that the toxicity of a pharmaceutical towards a non-target invertebrate depends on the presence of the human drug target orthologs in this species. This was tested by assessing toxicity of pharmaceuticals with (miconazole and promethazine and without (levonorgestrel identified drug target orthologs in the cladoceran Daphnia magna. The toxicity was evaluated using general toxicity endpoints at individual (immobility, reproduction and development, biochemical (RNA and DNA content and molecular (gene expression levels. The results provide evidence for higher toxicity of miconazole and promethazine, i.e. the drugs with identified drug target orthologs. At the individual level, miconazole had the lowest effect concentrations for immobility and reproduction (0.3 and 0.022 mg L-1, respectively followed by promethazine (1.6 and 0.18 mg L-1, respectively. At the biochemical level, individual RNA content was affected by miconazole and promethazine already at 0.0023 and 0.059 mg L-1, respectively. At the molecular level, gene expression for cuticle protein was significantly suppressed by exposure to both miconazole and promethazine; moreover, daphnids exposed to miconazole had significantly lower vitellogenin expression. Levonorgestrel did not have any effects on any endpoints in the concentrations tested. These results highlight the importance of considering drug target conservation in environmental risk assessments of pharmaceuticals.

    3. Are pharmaceuticals with evolutionary conserved molecular drug targets more potent to cause toxic effects in non-target organisms?

      Science.gov (United States)

      Furuhagen, Sara; Fuchs, Anne; Lundström Belleza, Elin; Breitholtz, Magnus; Gorokhova, Elena

      2014-01-01

      The ubiquitous use of pharmaceuticals has resulted in a continuous discharge into wastewater and pharmaceuticals and their metabolites are found in the environment. Due to their design towards specific drug targets, pharmaceuticals may be therapeutically active already at low environmental concentrations. Several human drug targets are evolutionary conserved in aquatic organisms, raising concerns about effects of these pharmaceuticals in non-target organisms. In this study, we hypothesized that the toxicity of a pharmaceutical towards a non-target invertebrate depends on the presence of the human drug target orthologs in this species. This was tested by assessing toxicity of pharmaceuticals with (miconazole and promethazine) and without (levonorgestrel) identified drug target orthologs in the cladoceran Daphnia magna. The toxicity was evaluated using general toxicity endpoints at individual (immobility, reproduction and development), biochemical (RNA and DNA content) and molecular (gene expression) levels. The results provide evidence for higher toxicity of miconazole and promethazine, i.e. the drugs with identified drug target orthologs. At the individual level, miconazole had the lowest effect concentrations for immobility and reproduction (0.3 and 0.022 mg L-1, respectively) followed by promethazine (1.6 and 0.18 mg L-1, respectively). At the biochemical level, individual RNA content was affected by miconazole and promethazine already at 0.0023 and 0.059 mg L-1, respectively. At the molecular level, gene expression for cuticle protein was significantly suppressed by exposure to both miconazole and promethazine; moreover, daphnids exposed to miconazole had significantly lower vitellogenin expression. Levonorgestrel did not have any effects on any endpoints in the concentrations tested. These results highlight the importance of considering drug target conservation in environmental risk assessments of pharmaceuticals.

    4. Associating Drugs, Targets and Clinical Outcomes into an Integrated Network Affords a New Platform for Computer-Aided Drug Repurposing

      DEFF Research Database (Denmark)

      Oprea, Tudor; Nielsen, Sonny Kim; Ursu, Oleg;

      2011-01-01

      benefit from an integrated, semantic-web compliant computer-aided drug repurposing (CADR) effort, one that would enable deep data mining of associations between approved drugs (D), targets (T), clinical outcomes (CO) and SE. We report preliminary results from text mining and multivariate statistics, based...

    5. High concentrations of drug in target tissues following local controlled release are utilized for both drug distribution and biologic effect: An example with epicardial inotropic drug delivery

      OpenAIRE

      Maslov, Mikhail Y.; Edelman, Elazer R.; Wei, Abraham E.; Pezone, Matthew J.; Lovich, Mark A.

      2013-01-01

      Local drug delivery preferentially loads target tissues with a concentration gradient from the surface or point of release that tapers down to more distant sites. Drug that diffuses down this gradient must be in unbound form, but such drug can only elicit a biologic effect through receptor interactions. Drug excess loads tissues, increasing gradients and driving penetration, but with limited added biological response. We examined the hypothesis that local application reduces dramatically syst...

    6. Targeted and non-targeted drug screening in whole blood by UHPLC-TOF-MS with data-independent acquisition

      DEFF Research Database (Denmark)

      Mollerup, Christian Brinch; Dalsgaard, Petur Weihe; Mardal, Marie;

      2016-01-01

      High-resolution mass spectrometry (HRMS) is widely used for the drug screening of biological samples in clinical and forensic laboratories. With the continuous addition of new psychoactive substances (NPS), keeping such methods updated is challenging. HRMS allows for combined targeted and non-targeted...... screening. The aims of the study were to apply a combined targeted and non-targeted screening approach to authentic driving-under-the-influence-of-drugs (DUID) samples (n = 44) and further validate the approach using whole-blood samples spiked with eleven low-dose synthetic benzodiazepine analogues (SBA......). Analytical data were acquired using ultra-high-performance liquid chromatography coupled with a time-of-flight mass spectrometer (UHPLC-TOF-MS) with data-independent acquisition (DIA). We present a combined targeted and non-targeted screening, where peak deconvolution and filtering reduced the number...

    7. In silico identification of candidate drug and vaccine targets from various pathways in Neisseria gonorrhoeae.

      Science.gov (United States)

      Barh, Debmalya; Kumar, Anil

      2009-01-01

      Neisseria gonorrhoeae is responsible for causing gonorrhea, one of the most common sexually transmitted diseases prevailing globally. Although extensive researches are in progress in order to control the transmission of the disease and to develop drug(s) against the pathogen, till date no effective vaccine or specific drug could be developed and only antibiotic treatment is in use. Perhaps, due to excess use of antibiotics, several resistant strains have been found. In the present study, metabolic pathways-related candidate drug and vaccine targets have been identified in N. gonorrhoeae virulent strain FA 1090 using an in silico subtractive genomics approach. 106 putative drug targets out of 537 essential genes have been predicted. 67 cytoplasmic and 9 membrane enzymes, along with 10 membrane transporters are found to be the potential drug targets from the host-pathogen common metabolic pathways. Among these targets, competence lipoproteins (NGO0277) and cysW have been identified as candidate vaccine targets. 20 drug targets have been identified from pathogen specific unique metabolic pathways. Out of these, 6 enzymes are involved in dual metabolic pathways and 2 are expressed in cell wall and fimbrium. These gonococci-specific proteins are expected to be better possible drug targets. Screening of the functional inhibitors against these novel targets may result in discovery of novel therapeutic compounds that can be effective against antibiotic resistant strains. PMID:20109152

    8. Glutamatergic Targets for Enhancing Extinction Learning in Drug Addiction

      OpenAIRE

      Cleva, R.M; Gass, J.T.; Widholm, J J; Olive, M.F.

      2010-01-01

      The persistence of the motivational salience of drug-related environmental cues and contexts is one of the most problematic obstacles to successful treatment of drug addiction. Behavioral approaches to extinguishing the salience of drug-associated cues, such as cue exposure therapy, have generally produced disappointing results which have been attributed to, among other things, the context specificity of extinction and inadequate consolidation of extinction learning. Extinction of any behavio...

    9. Current Status of Targets and Assays for Anti-HIV Drug Screening

      Institute of Scientific and Technical Information of China (English)

      2007-01-01

      HIV/AIDS is one of the most serious public health challenges globally. Despite the great efforts that are being devoted to prevent, treat and to better understand the disease, it is one of the main causes of morbidity and mortality worldwide. Currently, there are 30 drugs or combinations of drugs approved by FDA. Because of the side-effects, price and drug resistance, it is essential to discover new targets, to develop new technology and to find new anti-HIV drugs. This review summarizes the major targets and assays currently used in anti-HIV drug screening.

    10. Target Nanoparticles for Therapy - SANS and DLS of Drug Carrier Liposomes and Polymer Nanoparticles

      Science.gov (United States)

      Nawroth, T.; Johnson, R.; Krebs, L.; Khoshakhlagh, P.; Langguth, P.; Hellmann, N.; Goerigk, G.; Boesecke, P.; Bravin, A.; Le Duc, G.; Szekely, N.; Schweins, R.

      2016-09-01

      T arget Nano-Pharmaceutics shall improve therapy and diagnosis of severe diseases, e.g. cancer, by individual targeting of drug-loaded nano-pharmaceuticals towards cancer cells, and drug uptake receptors in other diseases. Specific ligands, proteins or cofactors, which are recognized by the diseased cells or cells of food and drug uptake, are bound to the nanoparticle surface, and thus capable of directing the drug carriers. The strategy has two branches: a) for parenteral cancer medicine a ligand set (2-5 different, surface-linked) are selected according to the biopsy analysis of the patient tissue e.g. from tumor.; b) in the oral drug delivery part the drug transport is enforced by excipients/ detergents in combination with targeting materials for cellular receptors resulting in an induced drug uptake. Both targeting nanomaterials are characterized by a combination of SANS + DLS and SAXS or ASAXS in a feedback process during development by synthesis, nanoparticle assembly and formulation.

    11. Selection between Michaelis–Menten and target-mediated drug disposition pharmacokinetic models

      OpenAIRE

      Yan, Xiaoyu; Mager, Donald E.; Krzyzanski, Wojciech

      2009-01-01

      Target-mediated drug disposition (TMDD) models have been applied to describe the pharmacokinetics of drugs whose distribution and/or clearance are affected by its target due to high binding affinity and limited capacity. The Michaelis–Menten (M–M) model has also been frequently used to describe the pharmacokinetics of such drugs. The purpose of this study is to investigate conditions for equivalence between M–M and TMDD pharmacokinetic models and provide guidelines for selection between these...

    12. On the possibility of the unification of drug targeting systems. Studies with liposome transport to the mixtures of target antigens.

      Science.gov (United States)

      Trubetskoy, V S; Berdichevsky, V R; Efremov, E E; Torchilin, V P

      1987-03-15

      In order to make the drug targeting system more effective, simple and technological, we suggest creation of drug-bearing conjugates capable of simultaneous binding with different antigenic components of the target via specific antibodies. It is supposed that the targeted therapy should include sequential administration of the mixture of modified antibodies (or other specific vectors) against different components of affected tissue and, upon antibody accumulation in the desired region, administration of modified drugs or drug carrying systems which can recognize and bind with the target via accumulated antibodies due to the interaction between vector modifier and carrier modifier. Using as a model system monolayers consisting of the mixture of extracellular antigens and appropriated antibodies, it was shown that the treatment of the target with the mixture of biotinylated antibodies against all target components and subsequent binding with the target of biotinylated liposomes via avidin permits high liposome accumulation on the monolayer. The binding achieved is always higher than in the case of the utilization of single antibody-bearing liposomes. Besides, the system suggested is very simple and its components can be easily obtained on technological scale in standardized conditions.

    13. Preparation and Optimization of Nanoemulsions for targeting Drug Delivery

      Directory of Open Access Journals (Sweden)

      Navneet Sharma

      2013-12-01

      Full Text Available Nanoemulsions have appeared as a novel drug delivery system which allows sustained or controlled release of drug, biological active ingredient and genetic material. Nanoemulsion is a dispersion consisting of oil, surfactant and an aqueous phase, which is a isotropically clear and thermo-dynamically or kinetically stable liquid solution, usually with droplet diameter within the range of 10-500nm. Although interest in nano-emulsions was developed for more than two decades now, mainly for nanoparticle preparation, it is in the last few years that direct applications of nano-emulsions in consumer products are being developed, mainly in pharmacy and cosmetics. These recent applications have made that studies on optimization methods for nano-emulsion preparation be a requirement. The design of effective formulations for drugs has long been a major task, because drug efficacy can severely limited by instability or poor solubility in the vehicle. Nanoemulsion is being applied to enhance the solubility and bioavailability of water insoluble drugs. The nanosized droplets leading to an enormous increase in interfacial areas associated with nanoemulsion would influence the transport properties of the drug [1, 2]. Recently, there has been a considerable attraction for this formulation, for the delivery of hydrophilic as well as hydrophobic drug as drug carriers because of its improved drug solubilization capacity, long shelf life, ease of preparation and improvement of bioavailability of drugs. This review is focused on the most recent literature on developments of nano-emulsions as final application products and on the optimization of their preparation.

    14. A Modular Probe Strategy for Drug Localization, Target Identification and Target Occupancy Measurement on Single Cell Level.

      Science.gov (United States)

      Rutkowska, Anna; Thomson, Douglas W; Vappiani, Johanna; Werner, Thilo; Mueller, Katrin M; Dittus, Lars; Krause, Jana; Muelbaier, Marcel; Bergamini, Giovanna; Bantscheff, Marcus

      2016-09-16

      Late stage failures of candidate drug molecules are frequently caused by off-target effects or inefficient target engagement in vivo. In order to address these fundamental challenges in drug discovery, we developed a modular probe strategy based on bioorthogonal chemistry that enables the attachment of multiple reporters to the same probe in cell extracts and live cells. In a systematic evaluation, we identified the inverse electron demand Diels-Alder reaction between trans-cyclooctene labeled probe molecules and tetrazine-tagged reporters to be the most efficient bioorthogonal reaction for this strategy. Bioorthogonal biotinylation of the probe allows the identification of drug targets in a chemoproteomics competition binding assay using quantitative mass spectrometry. Attachment of a fluorescent reporter enables monitoring of spatial localization of probes as well as drug-target colocalization studies. Finally, direct target occupancy of unlabeled drugs can be determined at single cell resolution by competitive binding with fluorescently labeled probe molecules. The feasibility of the modular probe strategy is demonstrated with noncovalent PARP inhibitors.

    15. A Modular Probe Strategy for Drug Localization, Target Identification and Target Occupancy Measurement on Single Cell Level.

      Science.gov (United States)

      Rutkowska, Anna; Thomson, Douglas W; Vappiani, Johanna; Werner, Thilo; Mueller, Katrin M; Dittus, Lars; Krause, Jana; Muelbaier, Marcel; Bergamini, Giovanna; Bantscheff, Marcus

      2016-09-16

      Late stage failures of candidate drug molecules are frequently caused by off-target effects or inefficient target engagement in vivo. In order to address these fundamental challenges in drug discovery, we developed a modular probe strategy based on bioorthogonal chemistry that enables the attachment of multiple reporters to the same probe in cell extracts and live cells. In a systematic evaluation, we identified the inverse electron demand Diels-Alder reaction between trans-cyclooctene labeled probe molecules and tetrazine-tagged reporters to be the most efficient bioorthogonal reaction for this strategy. Bioorthogonal biotinylation of the probe allows the identification of drug targets in a chemoproteomics competition binding assay using quantitative mass spectrometry. Attachment of a fluorescent reporter enables monitoring of spatial localization of probes as well as drug-target colocalization studies. Finally, direct target occupancy of unlabeled drugs can be determined at single cell resolution by competitive binding with fluorescently labeled probe molecules. The feasibility of the modular probe strategy is demonstrated with noncovalent PARP inhibitors. PMID:27384741

    16. For Some Skin Cancers, Targeted Drug Hits the Mark

      Science.gov (United States)

      Two studies reported June 7, 2012, in NEJM indicate that the drug vismodegib can elicit responses in people with advanced or metastatic basal cell carcinoma and help shrink or prevent tumors in those with basal cell nevus syndrome.

    17. The use of microbubbles to target drug delivery

      Directory of Open Access Journals (Sweden)

      Porter Richard

      2004-11-01

      Full Text Available Abstract Ultrasound-mediated microbubbles destruction has been proposed as an innovative method for noninvasive delivering of drugs and genes to different tissues. Microbubbles are used to carry a drug or gene until a specific area of interest is reached, and then ultrasound is used to burst the microbubbles, causing site-specific delivery of the bioactive materials. Furthermore, the ability of albumin-coated microbubbles to adhere to vascular regions with glycocalix damage or endothelial dysfunction is another possible mechanism to deliver drugs even in the absence of ultrasound. This review focuses on the characteristics of microbubbles that give them therapeutic properties and some important aspects of ultrasound parameters that are known to influence microbubble-mediated drug delivery. In addition, current studies involving this novel therapeutical application of microbubbles will be discussed.

    18. For Some Skin Cancers, Targeted Drug Hits the Mark

      Science.gov (United States)

      ... 29 new BCCs among those who received a placebo . However, more than half of the patients taking vismodegib discontinued treatment because of side effects. Once patients stopped taking the drug, tumors began ...

    19. Molecular Targets Versus Models for New Antiepileptic Drug Discovery

      OpenAIRE

      Rogawski, Michael A.

      2006-01-01

      Animal models have played a key role in the discovery and characterization of all marketed antiepileptic drugs (AED). The conventional wisdom is that the standard animal screening models are becoming obsolete because they fail to identify compounds that act in mechanistically new ways and as a result do not offer therapeutic advantages over presently available agents. In fact, far from only detecting me-too drugs, the models often uncover compounds with distinctive profiles of activity in var...

    20. Identification of drug targets by chemogenomic and metabolomic profiling in yeast

      KAUST Repository

      Wu, Manhong

      2012-12-01

      OBJECTIVE: To advance our understanding of disease biology, the characterization of the molecular target for clinically proven or new drugs is very important. Because of its simplicity and the availability of strains with individual deletions in all of its genes, chemogenomic profiling in yeast has been used to identify drug targets. As measurement of drug-induced changes in cellular metabolites can yield considerable information about the effects of a drug, we investigated whether combining chemogenomic and metabolomic profiling in yeast could improve the characterization of drug targets. BASIC METHODS: We used chemogenomic and metabolomic profiling in yeast to characterize the target for five drugs acting on two biologically important pathways. A novel computational method that uses a curated metabolic network was also developed, and it was used to identify the genes that are likely to be responsible for the metabolomic differences found. RESULTS AND CONCLUSION: The combination of metabolomic and chemogenomic profiling, along with data analyses carried out using a novel computational method, could robustly identify the enzymes targeted by five drugs. Moreover, this novel computational method has the potential to identify genes that are causative of metabolomic differences or drug targets. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

    1. Structure-based DNA-targeting strategies with small molecule ligands for drug discovery.

      Science.gov (United States)

      Sheng, Jia; Gan, Jianhua; Huang, Zhen

      2013-09-01

      Nucleic acids are the molecular targets of many clinical anticancer drugs. However, compared with proteins, nucleic acids have traditionally attracted much less attention as drug targets in structure-based drug design, partially because limited structural information of nucleic acids complexed with potential drugs is available. Over the past several years, enormous progresses in nucleic acid crystallization, heavy-atom derivatization, phasing, and structural biology have been made. Many complicated nucleic acid structures have been determined, providing new insights into the molecular functions and interactions of nucleic acids, especially DNAs complexed with small molecule ligands. Thus, opportunities have been created to further discover nucleic acid-targeting drugs for disease treatments. This review focuses on the structure studies of DNAs complexed with small molecule ligands for discovering lead compounds, drug candidates, and/or therapeutics.

    2. Predicted essential proteins ofPlasmodium falciparum for potential drug targets

      Institute of Scientific and Technical Information of China (English)

      Qing-Feng He; Li Deng; Qin-Ying Xu; Zheng Shao

      2012-01-01

      ABSTRACT Objective:To identify novel drug targets for treatment ofPlasmodium falciparum.Methods:LocalBLASTP were used to find the proteins non-homologous to human essential proteins as novel drug targets. Functional domains of novel drug targets were identified by InterPro and Pfam,3D structures of potential drug targets were predicated by theSWISS-MODELworkspace. Ligands and ligand-binding sites of the proteins were searched byEf-seek.Results:Three essential proteins were identified that might be considered as potential drug targets.AAN37254.1 belonged to1-deoxy-D-xylulose5-phosphate reductoisomerase,CAD50499.1 belonged to chorismate synthase,CAD51220.1 belonged toFAD binging3 family, but the function of CAD51220.1 was unknown. The3D structures, ligands and ligand-binding sites ofAAN37254.1 andCAD50499.1 were successfully predicated.Conclusions:Two of these potential drug targets are key enzymes in2-C-methyl-d-erythritol4-phosphate pathway and shikimate pathway, which are absent in humans, so these two essential proteins are good potential drug targets. The function and3D structures ofCAD50499.1 is still unknown, it still need further study.

    3. Delivery of drugs to intracellular organelles using drug delivery systems: Analysis of research trends and targeting efficiencies.

      Science.gov (United States)

      Maity, Amit Ranjan; Stepensky, David

      2015-12-30

      Targeting of drug delivery systems (DDSs) to specific intracellular organelles (i.e., subcellular targeting) has been investigated in numerous publications, but targeting efficiency of these systems is seldom reported. We searched scientific publications in the subcellular DDS targeting field and analyzed targeting efficiency and major formulation parameters that affect it. We identified 77 scientific publications that matched the search criteria. In the majority of these studies nanoparticle-based DDSs were applied, while liposomes, quantum dots and conjugates were used less frequently. The nucleus was the most common intracellular target, followed by mitochondrion, endoplasmic reticulum and Golgi apparatus. In 65% of the publications, DDSs surface was decorated with specific targeting residues, but the efficiency of this surface decoration was not analyzed in predominant majority of the studies. Moreover, only 23% of the analyzed publications contained quantitative data on DDSs subcellular targeting efficiency, while the majority of publications reported qualitative results only. From the analysis of publications in the subcellular targeting field, it appears that insufficient efforts are devoted to quantitative analysis of the major formulation parameters and of the DDSs' intracellular fate. Based on these findings, we provide recommendations for future studies in the field of organelle-specific drug delivery and targeting.

    4. Targeted drug delivery to the brain using magnetic nanoparticles.

      Science.gov (United States)

      Thomsen, Louiza Bohn; Thomsen, Maj Schneider; Moos, Torben

      2015-01-01

      Brain capillary endothelial cells denote the blood-brain barrier (BBB), and conjugation of nanoparticles with antibodies that target molecules expressed by these endothelial cells may facilitate their uptake and transport into the brain. Magnetic nanoparticles can be encapsulated in liposomes and carry large molecules with therapeutic potential, for example, siRNA, cDNA and polypeptides. An additional approach to enhance the transport of magnetic nanoparticles across the BBB is the application of extracranially applied magnetic force. Stepwise targeting of magnetic nanoparticles to brain capillary endothelial cells followed by transport through the BBB using magnetic force may prove a novel mechanism for targeted therapy of macromolecules to the brain.

    5. Advances in Bone-targeted Drug Delivery Systems for Neoadjuvant Chemotherapy for Osteosarcoma.

      Science.gov (United States)

      Li, Cheng-Jun; Liu, Xiao-Zhou; Zhang, Lei; Chen, Long-Bang; Shi, Xin; Wu, Su-Jia; Zhao, Jian-Ning

      2016-05-01

      Targeted therapy for osteosarcoma includes organ, cell and molecular biological targeting; of these, organ targeting is the most mature. Bone-targeted drug delivery systems are used to concentrate chemotherapeutic drugs in bone tissues, thus potentially resolving the problem of reaching the desired foci and minimizing the toxicity and adverse effects of neoadjuvant chemotherapy. Some progress has been made in bone-targeted drug delivery systems for treatment of osteosarcoma; however, most are still at an experimental stage and there is a long transitional period to clinical application. Therefore, determining how to combine new, polymolecular and multi-pathway targets is an important research aspect of designing new bone-targeted drug delivery systems in future studies. The purpose of this article was to review the status of research on targeted therapy for osteosarcoma and to summarize the progress made thus far in developing bone-targeted drug delivery systems for neoadjuvant chemotherapy for osteosarcoma with the aim of providing new ideas for highly effective therapeutic protocols with low toxicity for patients with osteosarcoma.

    6. Nitric oxide-related drug targets in headache

      DEFF Research Database (Denmark)

      Olesen, Jes

      2010-01-01

      SUMMARY: Nitric oxide (NO) is a very important molecule in the regulation of cerebral and extra cerebral cranial blood flow and arterial diameters. It is also involved in nociceptive processing. Glyceryl trinitrate (GTN), a pro-drug for NO, causes headache in normal volunteers and a so-called del......SUMMARY: Nitric oxide (NO) is a very important molecule in the regulation of cerebral and extra cerebral cranial blood flow and arterial diameters. It is also involved in nociceptive processing. Glyceryl trinitrate (GTN), a pro-drug for NO, causes headache in normal volunteers and a so...

    7. Chronic neuropathic pain: mechanisms, drug targets and measurement

      DEFF Research Database (Denmark)

      Finnerup, Nanna B; Sindrup, Søren H; Jensen, Troels S

      2007-01-01

      . Preclinical research provides several promising targets for treatment such as sodium and calcium channels, glutamate receptors, monoamines and neurotrophic factors; however, treatment is often insufficient. A mechanism-based treatment approach is suggested to improve treatment. Valid and reliable tools...

    8. One for All? Hitting Multiple Alzheimer's Disease Targets with One Drug.

      Science.gov (United States)

      Hughes, Rebecca E; Nikolic, Katarina; Ramsay, Rona R

      2016-01-01

      HIGHLIGHTS Many AD target combinations are being explored for multi-target drug design.New databases and models increase the potential of computational drug designLiraglutide and other antidiabetics are strong candidates for repurposing to AD.Donecopride a dual 5-HT/AChE inhibitor shows promise in pre-clinical studies Alzheimer's Disease is a complex and multifactorial disease for which the mechanism is still not fully understood. As new insights into disease progression are discovered, new drugs must be designed to target those aspects of the disease that cause neuronal damage rather than just the symptoms currently addressed by single target drugs. It is becoming possible to target several aspects of the disease pathology at once using multi-target drugs (MTDs). Intended as an introduction for non-experts, this review describes the key MTD design approaches, namely structure-based, in silico, and data-mining, to evaluate what is preventing compounds progressing through the clinic to the market. Repurposing current drugs using their off-target effects reduces the cost of development, time to launch, and the uncertainty associated with safety and pharmacokinetics. The most promising drugs currently being investigated for repurposing to Alzheimer's Disease are rasagiline, originally developed for the treatment of Parkinson's Disease, and liraglutide, an antidiabetic. Rational drug design can combine pharmacophores of multiple drugs, systematically change functional groups, and rank them by virtual screening. Hits confirmed experimentally are rationally modified to generate an effective multi-potent lead compound. Examples from this approach are ASS234 with properties similar to rasagiline, and donecopride, a hybrid of an acetylcholinesterase inhibitor and a 5-HT4 receptor agonist with pro-cognitive effects. Exploiting these interdisciplinary approaches, public-private collaborative lead factories promise faster delivery of new drugs to the clinic.

    9. Reduction in acute filariasis morbidity during a mass drug administration trial to eliminate lymphatic filariasis in Papua New Guinea.

      Directory of Open Access Journals (Sweden)

      Daniel J Tisch

      2011-07-01

      Full Text Available BACKGROUND: Acute painful swelling of the extremities and scrotum are debilitating clinical manifestations of Wuchereria bancrofti infection. The ongoing global program to eliminate filariasis using mass drug administration is expected to decrease this and other forms of filarial morbidity in the future by preventing establishment of new infections as a consequence of eliminating transmission by the mosquito vector. We examined whether mass treatment with anti-filarial drugs has a more immediate health benefit by monitoring acute filariasis morbidity in Papua New Guinean communities that participated in a 5-year mass drug administration trial. METHODOLOGY/PRINCIPAL FINDINGS: Weekly active surveillance for acute filariasis morbidity defined by painful swelling of the extremities, scrotum and breast was performed 1 year before and each year after 4 annual mass administrations of anti-filarial drugs (16,480 person-years of observation. Acute morbidity events lasted <3 weeks in 92% of affected individuals and primarily involved the leg (74-79% of all annual events. The incidence for all communities considered together decreased from 0.39 per person-year in the pre-treatment year to 0.31, 0.15, 0.19 and 0.20 after each of 4 annual treatments (p<0.0001. Residents of communities with high pre-treatment transmission intensities (224-742 infective bites/person/year experienced a greater reduction in acute morbidity (0.62 episodes per person-year pre-treatment vs. 0.30 in the 4(th post-treatment year than residents of communities with moderate pre-treatment transmission intensities (24-167 infective bites/person/year; 0.28 episodes per person-year pre-treatment vs. 0.16 in the 4(th post-treatment year. CONCLUSIONS: Mass administration of anti-filarial drugs results in immediate health benefit by decreasing the incidence of acute attacks of leg and arm swelling in people with pre-existing infection. Reduction in acute filariasis morbidity parallels

    10. PDTD: a web-accessible protein database for drug target identification

      Directory of Open Access Journals (Sweden)

      Gao Zhenting

      2008-02-01

      Full Text Available Abstract Background Target identification is important for modern drug discovery. With the advances in the development of molecular docking, potential binding proteins may be discovered by docking a small molecule to a repository of proteins with three-dimensional (3D structures. To complete this task, a reverse docking program and a drug target database with 3D structures are necessary. To this end, we have developed a web server tool, TarFisDock (Target Fishing Docking http://www.dddc.ac.cn/tarfisdock, which has been used widely by others. Recently, we have constructed a protein target database, Potential Drug Target Database (PDTD, and have integrated PDTD with TarFisDock. This combination aims to assist target identification and validation. Description PDTD is a web-accessible protein database for in silico target identification. It currently contains >1100 protein entries with 3D structures presented in the Protein Data Bank. The data are extracted from the literatures and several online databases such as TTD, DrugBank and Thomson Pharma. The database covers diverse information of >830 known or potential drug targets, including protein and active sites structures in both PDB and mol2 formats, related diseases, biological functions as well as associated regulating (signaling pathways. Each target is categorized by both nosology and biochemical function. PDTD supports keyword search function, such as PDB ID, target name, and disease name. Data set generated by PDTD can be viewed with the plug-in of molecular visualization tools and also can be downloaded freely. Remarkably, PDTD is specially designed for target identification. In conjunction with TarFisDock, PDTD can be used to identify binding proteins for small molecules. The results can be downloaded in the form of mol2 file with the binding pose of the probe compound and a list of potential binding targets according to their ranking scores. Conclusion PDTD serves as a comprehensive and

    11. Polymeric micelles with stimuli-triggering systems for advanced cancer drug targeting.

      Science.gov (United States)

      Nakayama, Masamichi; Akimoto, Jun; Okano, Teruo

      2014-08-01

      Since the 1990s, nanoscale drug carriers have played a pivotal role in cancer chemotherapy, acting through passive drug delivery mechanisms and subsequent pharmaceutical action at tumor tissues with reduction of adverse effects. Polymeric micelles, as supramolecular assemblies of amphiphilic polymers, have been considerably developed as promising drug carrier candidates, and a number of clinical studies of anticancer drug-loaded polymeric micelle carriers for cancer chemotherapy applications are now in progress. However, these systems still face several issues; at present, the simultaneous control of target-selective delivery and release of incorporated drugs remains difficult. To resolve these points, the introduction of stimuli-responsive mechanisms to drug carrier systems is believed to be a promising approach to provide better solutions for future tumor drug targeting strategies. As possible trigger signals, biological acidic pH, light, heating/cooling and ultrasound actively play significant roles in signal-triggering drug release and carrier interaction with target cells. This review article summarizes several molecular designs for stimuli-responsive polymeric micelles in response to variation of pH, light and temperature and discusses their potentials as next-generation tumor drug targeting systems.

    12. Discovering the first microRNA-targeted drug

      DEFF Research Database (Denmark)

      Lindow, Morten; Kauppinen, Sakari

      2012-01-01

      MicroRNAs (miRNAs) are important post-transcriptional regulators of nearly every biological process in the cell and play key roles in the pathogenesis of human disease. As a result, there are many drug discovery programs that focus on developing miRNA-based therapeutics. The most advanced...

    13. Emergence of the silicon human and network targeting drugs

      NARCIS (Netherlands)

      Kolodkin, Alexey; Boogerd, Fred C.; Plant, Nick; Bruggeman, Frank J.; Goncharuk, Valeri; Lunshof, Jeantine; Moreno-Sanchez, Rafael; Yilmaz, Nilgun; Bakker, Barbara M.; Snoep, Jacky L.; Balling, Rudi; Westerhoff, Hans V.

      2012-01-01

      The development of disease may be characterized as a pathological shift of homeostasis; the main goal of contemporary drug treatment is, therefore, to return the pathological homeostasis back to the normal physiological range. From the view point of systems biology, homeostasis emerges from the inte

    14. Molecular Communication Model for Targeted Drug Delivery in Multiple Disease Sites With Diversely Expressed Enzymes.

      Science.gov (United States)

      Chude-Okonkwo, Uche A K; Malekian, Reza; Maharaj, B T Sunil

      2016-04-01

      Targeted drug delivery (TDD) for disease therapy using liposomes as nanocarriers has received extensive attention in the literature. The liposome's ability to incorporate capabilities such as long circulation, stimuli responsiveness, and targeting characteristics, makes it a versatile nanocarrier. Timely drug release at the targeted site requires that trigger stimuli such as pH, light, and enzymes be uniquely overexpressed at the targeted site. However, in some cases, the targeted sites may not express trigger stimuli significantly, hence, achieving effective TDD at those sites is challenging. In this paper, we present a molecular communication-based TDD model for the delivery of therapeutic drugs to multiple sites that may or may not express trigger stimuli. The nanotransmitter and nanoreceiver models for the molecular communication system are presented. Here, the nanotransmitter and nanoreceiver are injected into the targeted body system's blood network. The compartmental pharmacokinetics model is employed to model the transportation of these therapeutic nanocarriers to the targeted sites where they are meant to anchor before the delivery process commences. We also provide analytical expressions for the delivered drug concentration. The effectiveness of the proposed model is investigated for drug delivery on tissue surfaces. Results show that the effectiveness of the proposed molecular communication-based TDD depends on parameters such as the total transmitter volume capacity, the receiver radius, the diffusion characteristic of the microenvironment of the targeted sites, and the concentration of the enzymes associated with the nanotransmitter and the nanoreceiver designs.

    15. Liposomal Tumor Targeting in Drug Delivery Utilizing MMP-2- and MMP-9-Binding Ligands

      Directory of Open Access Journals (Sweden)

      Oula Penate Medina

      2011-01-01

      Full Text Available Nanotechnology offers an alternative to conventional treatment options by enabling different drug delivery and controlled-release delivery strategies. Liposomes being especially biodegradable and in most cases essentially nontoxic offer a versatile platform for several different delivery approaches that can potentially enhance the delivery and targeting of therapies to tumors. Liposomes penetrate tumors spontaneously as a result of fenestrated blood vessels within tumors, leading to known enhanced permeability and subsequent drug retention effects. In addition, liposomes can be used to carry radioactive moieties, such as radiotracers, which can be bound at multiple locations within liposomes, making them attractive carriers for molecular imaging applications. Phage display is a technique that can deliver various high-affinity and selectivity peptides to different targets. In this study, gelatinase-binding peptides, found by phage display, were attached to liposomes by covalent peptide-PEG-PE anchor creating a targeted drug delivery vehicle. Gelatinases as extracellular targets for tumor targeting offer a viable alternative for tumor targeting. Our findings show that targeted drug delivery is more efficient than non-targeted drug delivery.

    16. Versatile surface engineering of porous nanomaterials with bioinspired polyphenol coatings for targeted and controlled drug delivery

      Science.gov (United States)

      Li, Juan; Wu, Shuxian; Wu, Cuichen; Qiu, Liping; Zhu, Guizhi; Cui, Cheng; Liu, Yuan; Hou, Weijia; Wang, Yanyue; Zhang, Liqin; Teng, I.-Ting; Yang, Huang-Hao; Tan, Weihong

      2016-04-01

      The development of biocompatible drug delivery systems with targeted recognition and controlled release has experienced a number of design challenges, including, for example, complicated preparation steps and premature drug release. Herein, we address these problems through an in situ self-polymerization method that synthesizes biodegradable polyphenol-coated porous nanomaterials for targeted and controlled drug delivery. As a proof of concept, we synthesized polyphenol-coated mesoporous silica nanoparticles, termed MSN@polyphenol. The polyphenol coatings not only improved colloidal stability and prevented premature drug leakage, but also provided a scaffold for immobilization of targeting moieties, such as aptamers. Both immobilization of targeting aptamers and synthesis of polyphenol coating are easily accomplished without the aid of any other organic reagents. Importantly, the polyphenol coating (EGCg) used in this study could be biodegraded by acidic pH and intracellular glutathione, resulting in the release of trapped anticancer drugs. Based on confocal fluorescence microscopy and cytotoxicity experiments, drug-loaded and polyphenol-coated MSNs were shown to possess highly efficient internalization and an apparent cytotoxic effect on target cancer, but not control, cells. Our results suggest that these highly biocompatible and biodegradable polyphenol-coated MSNs are promising vectors for controlled-release biomedical applications and cancer therapy.The development of biocompatible drug delivery systems with targeted recognition and controlled release has experienced a number of design challenges, including, for example, complicated preparation steps and premature drug release. Herein, we address these problems through an in situ self-polymerization method that synthesizes biodegradable polyphenol-coated porous nanomaterials for targeted and controlled drug delivery. As a proof of concept, we synthesized polyphenol-coated mesoporous silica nanoparticles

    17. Central nervous system myeloid cells as drug targets: current status and translational challenges.

      Science.gov (United States)

      Biber, Knut; Möller, Thomas; Boddeke, Erik; Prinz, Marco

      2016-02-01

      Myeloid cells of the central nervous system (CNS), which include parenchymal microglia, macrophages at CNS interfaces and monocytes recruited from the circulation during disease, are increasingly being recognized as targets for therapeutic intervention in neurological and psychiatric diseases. The origin of these cells in the immune system distinguishes them from ectodermal neurons and other glia and endows them with potential drug targets distinct from classical CNS target groups. However, despite the identification of several promising therapeutic approaches and molecular targets, no agents directly targeting these cells are currently available. Here, we assess strategies for targeting CNS myeloid cells and address key issues associated with their translation into the clinic.

    18. An inflammation-targeting hydrogel for local drug delivery in inflammatory bowel disease

      OpenAIRE

      Zhang, Sufeng; Ermann, Joerg; Succi, Marc D.; Zhou, Allen; Hamilton, Matthew J.; Cao, Bonnie; Korzenik, Joshua R.; Glickman, Jonathan N.; Vemula, Praveen K.; Glimcher, Laurie H.; Traverso, Giovanni; Langer, Robert; Karp, Jeffrey M.

      2015-01-01

      There is a clinical need for new, more effective treatments for chronic and debilitating inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis. Targeting drugs selectively to the inflamed intestine may improve therapeutic outcomes and minimize systemic toxicity. We report the development of an inflammation-targeting hydrogel (IT-hydrogel) that acts as a drug delivery system to the inflamed colon. Hydrogel microfibers were generated from ascorbyl palmitate, an amph...

    19. Shear-stress sensitive lenticular vesicles for targeted drug delivery

      Science.gov (United States)

      Holme, Margaret N.; Fedotenko, Illya A.; Abegg, Daniel; Althaus, Jasmin; Babel, Lucille; Favarger, France; Reiter, Renate; Tanasescu, Radu; Zaffalon, Pierre-Léonard; Ziegler, André; Müller, Bert; Saxer, Till; Zumbuehl, Andreas

      2012-08-01

      Atherosclerosis results in the narrowing of arterial blood vessels and this causes significant changes in the endogenous shear stress between healthy and constricted arteries. Nanocontainers that can release drugs locally with such rheological changes can be very useful. Here, we show that vesicles made from an artificial 1,3-diaminophospholipid are stable under static conditions but release their contents at elevated shear stress. These vesicles have a lenticular morphology, which potentially leads to instabilities along their equator. Using a model cardiovascular system based on polymer tubes and an external pump to represent shear stress in healthy and constricted vessels of the heart, we show that drugs preferentially release from the vesicles in constricted vessels that have high shear stress.

    20. Phenotypic drug profiling in droplet microfluidics for better targeting of drug-resistant tumors

      Science.gov (United States)

      Sarkar, S.; Cohen, N.; Sabhachandani, P.; Konry, T.

      2015-01-01

      Acquired drug resistance is a key factor in the failure of chemotherapy. Due to intratumoral heterogeneity, cancer cells depict variations in intracellular drug uptake and efflux at the single cell level, which may not be detectable in bulk assays. In this study we present a droplet microfluidics-based approach to assess the dynamics of drug uptake, efflux and cytotoxicity in drug-sensitive and drug-resistant breast cancer cells. An integrated droplet generation and docking microarray was utilized to encapsulate single cells as well as homotypic cell aggregates. Drug-sensitive cells showed greater death in the presence or absence of Doxorubicin (Dox) compared to the drug-resistant cells. We observed heterogeneous Dox uptake in individual drug-sensitive cells while the drug-resistant cells showed uniformly low uptake and retention. Dox-resistant cells were classified into distinct subsets based on their efflux properties. Cells that showed longer retention of extracellular reagents also demonstrated maximal death. We further observed homotypic fusion of both cell types in droplets, which resulted in increased cell survival in the presence of high doses of Dox. Our results establish the applicability of this microfluidic platform for quantitative drug screening in single cells and multicellular interactions. PMID:26456240

    1. Approaches to target identification and validation for tuberculosis drug discovery: a UCT perspective.

      Science.gov (United States)

      Warner, Digby F; Mizrahi, Valerie

      2012-06-01

      Tuberculosis (TB) disproportionately affects a few high-burden countries including South Africa. In these regions, basic TB research is rare, endemic countries being valued primarily as sites for drug trials and clinical studies. Our basic mycobacterial research focuses on current approaches to drug target identification and validation within the context of international trends in TB drug discovery. Increased funding for TB drug development globally prompted a significant shift in the composition of drug discovery consortia, with academic laboratories assuming a major role in collaboration with industrial partners. This hybrid model holds promise for the expansion of local programmes, especially where actively supported by government. However, the application of industry-standard business practices to research projects involving biology and chemistry expertise demands a greater appreciation of the differences between a chemically, versus biologically, validated drug target, and of the factors informing these differences. PMID:22668936

    2. New development and application of ultrasound targeted microbubble destruction in gene therapy and drug delivery.

      Science.gov (United States)

      Chen, Zhi-Yi; Yang, Feng; Lin, Yan; Zhang, Jin-Shan; Qiu, Ri-Xiang; Jiang, Lan; Zhou, Xing-Xing; Yu, Jiang-Xiu

      2013-08-01

      Ultrasound is a common used technique for clinical imaging. In recent years, with the advances in preparation technology of microbubbles and the innovations in ultrasound imaging, ultrasound is no longer confined to detection of tissue perfusion, but extends to specific ultrasound molecular imaging and target therapy gradually. With the development of research, ultrasound molecular imaging and target therapy have made great progresses. Targeted microbubbles for molecular imaging are achieved by binding target molecules, specific antibody or ligand to the surface of microbubbles to obtain specific imaging by attaching to target tissues. Meanwhile, it can also achieve targeting gene therapy or drug delivery by ultrasound targeted microbubble destruction (UTMD) mediating genes or drugs to specific target sites. UTMD has a number of advantages, such as target-specific, highly effective, non-invasivity, relatively low-cost and no radiation, and has broad application prospects, which is regarded as one hot spot in medical studies. We reviewed the new development and application of UTMD in gene therapy and drug delivery in this paper. With further development of technology and research, the gene or drug delivery system and related methods will be widely used in application and researches.

    3. Investigation on a Potential Targeting Drug Delivery System Consisting of Folate, Mitoxantrone and Human Serum Albumin

      Institute of Scientific and Technical Information of China (English)

      ZHOU Qiu-Jua; BI Ya-Jing; XIANG Jun-Feng; TANG Ya-Lin; YANG Qian-Fan; XU Guang-Zhi

      2008-01-01

      A potential targeting drug delivery system consisting of folate (FA), the targeting molecule, human serum al- bumin (HSA), the carrier, and mitoxantrone (MTO), the medicine, has been designed. Data obtained by UV absorp-tion, fluorescence, and NMR techniques indicated the formation of ternary complexes and possible application to building a targeting drug delivery system by using FA, MTO and HSA. Furthermore, cytotoxicity assay indicated that the toxicity of the FA-HSA-MTO against PC-3 cell line was 79.95%, which was much higher than that of free MTO tested in totally the same conditions. About 30% increase of the toxicity should be owed to the targeting ef-fect of FA. Thus, the feasibility and validity of a novel targeting drug delivery system, FA-HSA-MTO, was con-firmed.

    4. Grants4Targets - an innovative approach to translate ideas from basic research into novel drugs.

      Science.gov (United States)

      Lessl, Monika; Schoepe, Stefanie; Sommer, Anette; Schneider, Martin; Asadullah, Khusru

      2011-04-01

      Collaborations between industry and academia are steadily gaining importance. To combine expertises Bayer Healthcare has set up a novel open innovation approach called Grants4Targets. Ideas on novel drug targets can easily be submitted to http://www.grants4targets.com. After a review process, grants are provided to perform focused experiments to further validate the proposed targets. In addition to financial support specific know-how on target validation and drug discovery is provided. Experienced scientists are nominated as project partners and, depending on the project, tools or specific models are provided. Around 280 applications have been received and 41 projects granted. According to our experience, this type of bridging fund combined with joint efforts provides a valuable tool to foster drug discovery collaborations.

    5. A new look at drugs targeting malignant melanoma--an application for mass spectrometry imaging.

      Science.gov (United States)

      Sugihara, Yutaka; Végvári, Akos; Welinder, Charlotte; Jönsson, Göran; Ingvar, Christian; Lundgren, Lotta; Olsson, Håkan; Breslin, Thomas; Wieslander, Elisabet; Laurell, Thomas; Rezeli, Melinda; Jansson, Bo; Nishimura, Toshihide; Fehniger, Thomas E; Baldetorp, Bo; Marko-Varga, György

      2014-09-01

      Malignant melanoma (MM) patients are being treated with an increasing number of personalized medicine (PM) drugs, several of which are small molecule drugs developed to treat patients with specific disease genotypes and phenotypes. In particular, the clinical application of protein kinase inhibitors has been highly effective for certain subsets of MM patients. Vemurafenib, a protein kinase inhibitor targeting BRAF-mutated protein, has shown significant efficacy in slowing disease progression. In this paper, we provide an overview of this new generation of targeted drugs, and demonstrate the first data on localization of PM drugs within tumor compartments. In this study, we have introduced MALDI-MS imaging to provide new information on one of the drugs currently used in the PM treatment of MM, vemurafenib. In a proof-of-concept in vitro study, MALDI-MS imaging was used to identify vemurafenib applied to metastatic lymph nodes tumors of subjects attending the regional hospital network of Southern Sweden. The paper provides evidence of BRAF overexpression in tumors isolated from MM patients and localization of the specific drug targeting BRAF, vemurafenib, using MS fragment ion signatures. Our ability to determine drug uptake at the target sites of directed therapy provides important opportunity for increasing our understanding about the mode of action of drug activity within the disease environment. PMID:25044963

    6. DRUG TARGETING TO THE KIDNEY WITH LOW-MOLECULAR-WEIGHT PROTEINS

      NARCIS (Netherlands)

      FRANSSEN, EJF; MOOLENAAR, F; DEZEEUW, D; MEIJER, DKF

      1993-01-01

      This paper reviews the design of a drug targeting strategy for renal specific delivery and endorenal release of drugs using low-molecular-weight proteins (LMWPs). In general, LMWPs are known to be filtered and subsequently reabsorbed by the proximal tubular cells of the kidneys. Within these cells L

    7. Genome-wide identification of structural variants in genes encoding drug targets

      DEFF Research Database (Denmark)

      Rasmussen, Henrik Berg; Dahmcke, Christina Mackeprang

      2012-01-01

      The objective of the present study was to identify structural variants of drug target-encoding genes on a genome-wide scale. We also aimed at identifying drugs that are potentially amenable for individualization of treatments based on knowledge about structural variation in the genes encoding...

    8. MITOCHONDRIA: INSIGHT TARGET OF DRUG DEVELOPMENT IN CANCER CELLS

      OpenAIRE

      Md. Ataur Rahman

      2012-01-01

      Mitochondria are involved in different physiological and pathological processes that are crucial for tumor cell physiology, growth and survival and its dysfunction leads to many human abnormalities, including cardiovascular diseases, neurodegenerative diseases, autoimmune disorders and cancer. The present review is focused on the different experimental and therapeutic cancer strategies addressed to either target mitochondria directly, or use mitochondria as mediators of apoptosis, although it...

    9. Protein target discovery of drug and its reactive intermediate metabolite by using proteomic strategy

      OpenAIRE

      Lianghai Hu; John Paul Fawcett; Jingkai Gu

      2012-01-01

      Identifying protein targets of bioactive compounds is an effective approach to discover unknown protein functions, identify molecular mechanisms of drug action, and obtain information for optimization of lead compounds. At the same time, metabolic activation of a drug can lead to cytotoxicities. Therefore, it is very important to systemically characterize the drug and its reactive intermediate. Mass spectrometry-based proteomic approach has emerged as the most efficient to study protein funct...

    10. Smuggling Drugs into the Brain: An Overview of Ligands Targeting Transcytosis for Drug Delivery across the Blood-Brain Barrier

      NARCIS (Netherlands)

      Zuhorn, Inge; Georgieva, Julia V.; Hoekstra, Dick

      2015-01-01

      The blood-brain barrier acts as a physical barrier that prevents free entry of blood-derived substances, including those intended for therapeutic applications. The development of molecular Trojan horses is a promising drug targeting technology that allows for non-invasive delivery of therapeutics in

    11. Nanoemulsion-based intranasal drug delivery system of saquinavir mesylate for brain targeting.

      Science.gov (United States)

      Mahajan, Hitendra S; Mahajan, Milind S; Nerkar, Pankaj P; Agrawal, Anshuman

      2014-03-01

      The central nervous system (CNS) is an immunological privileged sanctuary site-providing reservoir for HIV-1 virus. Current anti-HIV drugs, although effective in reducing plasma viral levels, cannot eradicate the virus completely from the body. The low permeability of anti-HIV drugs across the blood-brain barrier (BBB) leads to insufficient delivery. Therefore, developing a novel approaches enhancing the CNS delivery of anti-HIV drugs are required for the treatment of neuro-AIDS. The aim of this study was to develop intranasal nanoemulsion (NE) for enhanced bioavailability and CNS targeting of saquinavir mesylate (SQVM). SQVM is a protease inhibitor which is a poorly soluble drug widely used as antiretroviral drug, with oral bioavailability is about 4%. The spontaneous emulsification method was used to prepare drug-loaded o/w nanoemulsion, which was characterized by droplet size, zeta potential, pH, drug content. Moreover, ex-vivo permeation studies were performed using sheep nasal mucosa. The optimized NE showed a significant increase in drug permeation rate compared to the plain drug suspension (PDS). Cilia toxicity study on sheep nasal mucosa showed no significant adverse effect of SQVM-loaded NE. Results of in vivo biodistribution studies show higher drug concentration in brain after intranasal administration of NE than intravenous delivered PDS. The higher percentage of drug targeting efficiency (% DTE) and nose-to-brain drug direct transport percentage (% DTP) for optimized NE indicated effective CNS targeting of SQVM via intranasal route. Gamma scintigraphy imaging of the rat brain conclusively demonstrated transport of drug in the CNS at larger extent after intranasal administration as NE.

    12. One For All? Hitting multiple Alzheimer’s Disease targets with one drug

      Directory of Open Access Journals (Sweden)

      Rebecca Ellen Hughes

      2016-04-01

      Full Text Available Alzheimer’s disease is a complex and multifactorial disease for which the mechanism is still not fully understood. As new insights into disease progression are discovered, new drugs must be designed to target those aspects of the disease that cause neuronal damage rather than just the symptoms currently addressed by single target drugs. It is becoming possible to target several aspects of the disease pathology at once using multi-target drugs. Intended as a introduction for non-experts, this review describes the key multi-target drug design approaches, namely structure-based, in silico, and data-mining, to evaluate what is preventing compounds progressing through the clinic to the market. Repurposing current drugs using their off-target effects reduces the cost of development, time to launch and also the uncertainty associated with safety and pharmacokinetics. The most promising drugs currently being investigated for repurposing to Alzheimer’s Disease are rasagiline, originally developed for the treatment of Parkinson’s Disease, and liraglutide, an antidiabetic. Rational drug design can combine pharmacophores of multiple drugs, systematically change functional groups, and rank them by virtual screening. Hits confirmed experimentally are rationally modified to generate an effective multi-potent lead compound. Examples from this approach are ASS234 with properties similar to rasagiline, and donecopride, a hybrid of an acetylcholinesterase inhibitor and a 5-HT4 receptor agonist with pro-cognitive effects. Exploiting these interdisciplinary approaches, public-private collaborative lead factories promise faster delivery of new drugs to the clinic.

    13. Quantitative modeling of selective lysosomal targeting for drug design

      DEFF Research Database (Denmark)

      Trapp, Stefan; Rosania, G.; Horobin, R.W.;

      2008-01-01

      the diffusion of neutral and ionic molecules across biomembranes, protonation to mono- or bivalent ions, adsorption to lipids, and electrical attraction or repulsion. Based on simulation results, high and selective accumulation in lysosomes was found for weak mono- and bivalent bases with intermediate to high...... predicted by the model and three were close. Five of the antimalarial drugs were lipophilic weak dibasic compounds. The predicted optimum properties for a selective accumulation of weak bivalent bases in lysosomes are consistent with experimental values and are more accurate than any prior calculation...

    14. Targeting aerobic glycolysis: 3-bromopyruvate as a promising anticancer drug.

      Science.gov (United States)

      Cardaci, Simone; Desideri, Enrico; Ciriolo, Maria Rosa

      2012-02-01

      The Warburg effect refers to the phenomenon whereby cancer cells avidly take up glucose and produce lactic acid under aerobic conditions. Although the molecular mechanisms underlying tumor reliance on glycolysis remains not completely clear, its inhibition opens feasible therapeutic windows for cancer treatment. Indeed, several small molecules have emerged by combinatorial studies exhibiting promising anticancer activity both in vitro and in vivo, as a single agent or in combination with other therapeutic modalities. Therefore, besides reviewing the alterations of glycolysis that occur with malignant transformation, this manuscript aims at recapitulating the most effective pharmacological therapeutics of its targeting. In particular, we describe the principal mechanisms of action and the main targets of 3-bromopyruvate, an alkylating agent with impressive antitumor effects in several models of animal tumors. Moreover, we discuss the chemo-potentiating strategies that would make unparalleled the putative therapeutic efficacy of its use in clinical settings. PMID:22328057

    15. [New targets and new drugs in thoracic oncology].

      Science.gov (United States)

      Rouviere, D; Bousquet, E; Pons, E; Milia, J-D; Guibert, N; Mazieres, J

      2015-10-01

      A number of mechanisms that drive oncogenesis have been deciphered over the last 20 years. The main oncogenic factors in the field of thoracic oncology are mutations of EGFR, KRAS, and EML4-ALK translocation, which are most often reported in adenocarcinomas. However, new molecular targets have been highlighted recently including BRAF mutations, HER2 or PI3K, new translocations such as ROS1 or KIF5B-RET. Molecular abnormalities have also been identified in tumors other than adenocarcinoma (squamous and small cell carcinoma). Therapeutic strategies have been designed to inhibit these signaling pathways including monoclonal antibodies and tyrosine kinase inhibitors. Some of these molecules are now approved as therapies, others are currently undergoing testing in clinical trials. We here present a review of novel targeted agents for lung cancer.

    16. Anti-cancer drug loaded iron-gold core-shell nanoparticles (Fe@Au) for magnetic drug targeting.

      Science.gov (United States)

      Kayal, Sibnath; Ramanujan, Raju Vijayaraghavan

      2010-09-01

      Magnetic drug targeting, using core-shell magnetic carrier particles loaded with anti-cancer drugs, is an emerging and significant method of cancer treatment. Gold shell-iron core nanoparticles (Fe@Au) were synthesized by the reverse micelle method with aqueous reactants, surfactant, co-surfactant and oil phase. XRD, XPS, TEM and magnetic property measurements were utilized to characterize these core-shell nanoparticles. Magnetic measurements showed that the particles were superparamagnetic at room temperature and that the saturation magnetization decreased with increasing gold concentration. The anti-cancer drug doxorubicin (DOX) was loaded onto these Fe@Au nanoparticle carriers and the drug release profiles showed that upto 25% of adsorbed drug was released in 80 h. It was found that the amine (-NH2) group of DOX binds to the gold shell. An in vitro apparatus simulating the human circulatory system was used to determine the retention of these nanoparticle carriers when exposed to an external magnetic field. A high percentage of magnetic carriers could be retained for physiologically relevant flow speeds of fluid. The present findings show that DOX loaded gold coated iron nanoparticles are promising for magnetically targeted drug delivery. PMID:21133071

    17. Chemical Genomics and Emerging DNA Technologies in the Identification of Drug Mechanisms and Drug Targets

      DEFF Research Database (Denmark)

      Olsen, Louise Cathrine Braun; Færgeman, Nils J.

      2012-01-01

      critical roles in the genomic age of biological research and drug discovery. In the present review we discuss how simple biological model organisms can be used as screening platforms in combination with emerging genomic technologies to advance the identification of potential drugs and their molecular...

    18. Label-free integrative pharmacology on-target of drugs at the β2-adrenergic receptor

      Science.gov (United States)

      Ferrie, Ann M.; Sun, Haiyan; Fang, Ye

      2011-07-01

      We describe a label-free integrative pharmacology on-target (iPOT) method to assess the pharmacology of drugs at the β2-adrenergic receptor. This method combines dynamic mass redistribution (DMR) assays using an array of probe molecule-hijacked cells with similarity analysis. The whole cell DMR assays track cell system-based, ligand-directed, and kinetics-dependent biased activities of the drugs, and translates their on-target pharmacology into numerical descriptors which are subject to similarity analysis. We demonstrate that the approach establishes an effective link between the label-free pharmacology and in vivo therapeutic indications of drugs.

    19. Neoadjuvant Window Studies of Metformin and Biomarker Development for Drugs Targeting Cancer Metabolism.

      Science.gov (United States)

      Lord, Simon R; Patel, Neel; Liu, Dan; Fenwick, John; Gleeson, Fergus; Buffa, Francesca; Harris, Adrian L

      2015-05-01

      There has been growing interest in the potential of the altered metabolic state typical of cancer cells as a drug target. The antidiabetes drug, metformin, is now under intense investigation as a safe method to modify cancer metabolism. Several studies have used window of opportunity in breast cancer patients before neoadjuvant chemotherapy to correlate gene expression analysis, metabolomics, immunohistochemical markers, and metabolic serum markers with those likely to benefit. We review the role metabolite measurement, functional imaging and gene sequencing analysis play in elucidating the effects of metabolically targeted drugs in cancer treatment and determining patient selection. PMID:26063894

    20. Transcription factors as targets for DNA-interacting drugs.

      Science.gov (United States)

      Gniazdowski, Marek; Denny, William A; Nelson, Stephanie M; Czyz, Malgorzata

      2003-06-01

      Gene expression, both tissue specific or inducible, is controlled at the level of transcription by various transcription factors interacting with specific sequences of DNA. Anticancer drugs and other potential therapeutic agents alter interactions of regulatory proteins with DNA by a variety of different mechanisms. The main ones, considered in the review, are: i) competition for the transcription factor DNA binding sequences by drugs that interact non-covalently with DNA (e.g. anthracyclines, acridines, actinomycin D, pyrrole antibiotics and their polyamide derivatives); ii) covalent modifications of DNA by alkylating agents (e.g. nitrogen mustards, cisplatin) that prevent transcription factors from recognizing their specific sequences, or that result in multiple "unnatural" binding sites in DNA which hijack the transcription factors, thus decreasing their availability in the nucleus; iii) competition with binding sites on the transcription factors by synthetic oligonucleotides or peptide nucleic acids in an antigene strategy. The latter compounds may also compete for binding sites on regulatory proteins, acting as decoys to lower their active concentration in the cell. In this review, we have summarized recent advances which have been made towards understanding the above mechanisms by which small molecules interfere with the function of transcription factors. PMID:12678680

    1. Visualization of network target crosstalk optimizes drug synergism in myocardial ischemia.

      Directory of Open Access Journals (Sweden)

      Xiaojing Wan

      Full Text Available Numerous drugs and compounds have been validated as protecting against myocardial ischemia (MI, a leading cause of heart failure; however, synergistic possibilities among them have not been systematically explored. Thus, there appears to be significant room for optimization in the field of drug combination therapy for MI. Here, we propose an easy approach for the identification and optimization of MI-related synergistic drug combinations via visualization of the crosstalk between networks of drug targets corresponding to different drugs (each drug has a unique network of targets. As an example, in the present study, 28 target crosstalk networks (TCNs of random pairwise combinations of 8 MI-related drugs (curcumin, capsaicin, celecoxib, raloxifene, silibinin, sulforaphane, tacrolimus, and tamoxifen were established to illustrate the proposed method. The TCNs revealed a high likelihood of synergy between curcumin and the other drugs, which was confirmed by in vitro experiments. Further drug combination optimization showed a synergistic protective effect of curcumin, celecoxib, and sililinin in combination against H₂O₂-induced ischemic injury of cardiomyocytes at a relatively low concentration of 500 nM. This result is in agreement with the earlier finding of a denser and modular functional crosstalk between their networks of targets in the regulation of cell apoptosis. Our study offers a simple approach to rapidly search for and optimize potent synergistic drug combinations, which can be used for identifying better MI therapeutic strategies. Some new light was also shed on the characteristic features of drug synergy, suggesting that it is possible to apply this method to other complex human diseases.

    2. Reverse Chemical Genetics: Comprehensive Fitness Profiling Reveals the Spectrum of Drug Target Interactions

      Science.gov (United States)

      Sinha, Sunita; Bergeron, Julien R.; Mellor, Joseph C.; Giaever, Guri; Nislow, Corey

      2016-01-01

      The emergence and prevalence of drug resistance demands streamlined strategies to identify drug resistant variants in a fast, systematic and cost-effective way. Methods commonly used to understand and predict drug resistance rely on limited clinical studies from patients who are refractory to drugs or on laborious evolution experiments with poor coverage of the gene variants. Here, we report an integrative functional variomics methodology combining deep sequencing and a Bayesian statistical model to provide a comprehensive list of drug resistance alleles from complex variant populations. Dihydrofolate reductase, the target of methotrexate chemotherapy drug, was used as a model to identify functional mutant alleles correlated with methotrexate resistance. This systematic approach identified previously reported resistance mutations, as well as novel point mutations that were validated in vivo. Use of this systematic strategy as a routine diagnostics tool widens the scope of successful drug research and development. PMID:27588687

    3. Reverse Chemical Genetics: Comprehensive Fitness Profiling Reveals the Spectrum of Drug Target Interactions.

      Science.gov (United States)

      Wong, Lai H; Sinha, Sunita; Bergeron, Julien R; Mellor, Joseph C; Giaever, Guri; Flaherty, Patrick; Nislow, Corey

      2016-09-01

      The emergence and prevalence of drug resistance demands streamlined strategies to identify drug resistant variants in a fast, systematic and cost-effective way. Methods commonly used to understand and predict drug resistance rely on limited clinical studies from patients who are refractory to drugs or on laborious evolution experiments with poor coverage of the gene variants. Here, we report an integrative functional variomics methodology combining deep sequencing and a Bayesian statistical model to provide a comprehensive list of drug resistance alleles from complex variant populations. Dihydrofolate reductase, the target of methotrexate chemotherapy drug, was used as a model to identify functional mutant alleles correlated with methotrexate resistance. This systematic approach identified previously reported resistance mutations, as well as novel point mutations that were validated in vivo. Use of this systematic strategy as a routine diagnostics tool widens the scope of successful drug research and development. PMID:27588687

    4. Novel Methods for Drug-Target Interaction Prediction using Graph Mining

      KAUST Repository

      Ba Alawi, Wail

      2016-08-31

      The problem of developing drugs that can be used to cure diseases is important and requires a careful approach. Since pursuing the wrong candidate drug for a particular disease could be very costly in terms of time and money, there is a strong interest in minimizing such risks. Drug repositioning has become a hot topic of research, as it helps reduce these risks significantly at the early stages of drug development by reusing an approved drug for the treatment of a different disease. Still, finding new usage for a drug is non-trivial, as it is necessary to find out strong supporting evidence that the proposed new uses of drugs are plausible. Many computational approaches were developed to narrow the list of possible candidate drug-target interactions (DTIs) before any experiments are done. However, many of these approaches suffer from unacceptable levels of false positives. We developed two novel methods based on graph mining networks of drugs and targets. The first method (DASPfind) finds all non-cyclic paths that connect a drug and a target, and using a function that we define, calculates a score from all the paths. This score describes our confidence that DTI is correct. We show that DASPfind significantly outperforms other state-of-the-art methods in predicting the top ranked target for each drug. We demonstrate the utility of DASPfind by predicting 15 novel DTIs over a set of ion channel proteins, and confirming 12 out of these 15 DTIs through experimental evidence reported in literature and online drug databases. The second method (DASPfind+) modifies DASPfind in order to increase the confidence and reliability of the resultant predictions. Based on the structure of the drug-target interaction (DTI) networks, we introduced an optimization scheme that incrementally alters the network structure locally for each drug to achieve more robust top 1 ranked predictions. Moreover, we explored effects of several similarity measures between the targets on the prediction

    5. Identification of potential drug targets in Helicobacter pylori strain HPAG1 by in silico genome analysis.

      Science.gov (United States)

      Neelapu, Nageswara R R; Mutha, Naresh V R; Akula, Srinivas

      2015-01-01

      Helicobacter pylori colonizes the stomach, causing gastritis, peptic ulcers and gastric carcinoma. Drugs for treatment of H. pylori relieve from gastritis or pain but are not specific to H. pylori. Therefore, there is an immediate requirement for new therapeutic molecules to treat H. pylori. Current study investigates identification of drug targets in the strain HPAG1 of H. pylori by in silico genome analysis. Genome of HPAG1 was reconstructed for metabolic pathways and compared with Homosapien sapiens to identify genes which are unique to H. pylori. These unique genes were subjected to gene property analysis to identify the potentiality of the drug targets. Among the total number of genes analysed in H. pylori strain HPAG1, nearly 542 genes qualified as unique molecules and among them 29 were identified to be potential drug targets. Co/Zn/Cd efflux system membrane fusion protein, Ferric sidephore transport system and biopolymer transport protein EXbB were found to be critical drug targets to H. pylori HPAG1. Five genes (superoxide dismutase, HtrA protease/chaperone protein, Heatinducible transcription repressor HrcA, HspR, transcriptional repressor of DnaK operon, Cobalt-zinccadmium resistance protein CzcA) of the 29 predicted drug targets are already experimentally validated either genetically or biochemically lending credence to our unique approach. PMID:26205802

    6. UDP-galactopyranose mutase, a potential drug target against human pathogenic nematode Brugia malayi.

      Science.gov (United States)

      Misra, Sweta; Valicherla, Guru R; Mohd Shahab; Gupta, Jyoti; Gayen, Jiaur R; Misra-Bhattacharya, Shailja

      2016-08-01

      Lymphatic filariasis, a vector-borne neglected tropical disease affects millions of population in tropical and subtropical countries. Vaccine unavailability and emerging drug resistance against standard antifilarial drugs necessitate search of novel drug targets for developing alternate drugs. Recently, UDP-galactopyranose mutases (UGM) have emerged as a promising drug target playing an important role in parasite virulence and survival. This study deals with the cloning and characterization of Brugia malayi UGM and further exploring its antifilarial drug target potential. The recombinant protein was actively involved in conversion of UDP-galactopyranose (substrate) to UDP-galactofuranose (product) revealing Km and Vmax to be ∼51.15 μM and ∼1.27 μM/min, respectively. The purified protein appeared to be decameric in native state and its 3D homology modeling using Aspergillus fumigatus UGM enzyme as template revealed conservation of active site residues. Two specific prokaryotic inhibitors (compounds A and B) of the enzyme inhibited B. malayi UGM enzymatic activity competitively depicting Ki values ∼22.68 and ∼23.0 μM, respectively. These compounds were also active in vitro and in vivo against B. malayi The findings suggest that B. malayi UGM could be a potential antifilarial therapeutic drug target. PMID:27465638

    7. Representation of target-bound drugs by computed conformers: implications for conformational libraries

      Directory of Open Access Journals (Sweden)

      Goede Andrean

      2006-06-01

      Full Text Available Abstract Background The increasing number of known protein structures provides valuable information about pharmaceutical targets. Drug binding sites are identifiable and suitable lead compounds can be proposed. The flexibility of ligands is a critical point for the selection of potential drugs. Since computed 3D structures of millions of compounds are available, the knowledge of their binding conformations would be a great benefit for the development of efficient screening methods. Results Integration of two public databases allowed superposition of conformers for 193 approved drugs with 5507 crystallised target-bound counterparts. The generation of 9600 drug conformers using an atomic force field was carried out to obtain an optimal coverage of the conformational space. Bioactive conformations are best described by a conformational ensemble: half of all drugs exhibit multiple active states, distributed over the entire range of the reachable energy and conformational space. A number of up to 100 conformers per drug enabled us to reproduce the bound states within a similarity threshold of 1.0 Å in 70% of all cases. This fraction rises to about 90% for smaller or average sized drugs. Conclusion Single drugs adopt multiple bioactive conformations if they interact with different target proteins. Due to the structural diversity of binding sites they adopt conformations that are distributed over a broad conformational space and wide energy range. Since the majority of drugs is well represented by a predefined low number of conformers (up to 100 this procedure is a valuable method to compare compounds by three-dimensional features or for fast similarity searches starting with pharmacophores. The underlying 9600 generated drug conformers are downloadable from the Super Drug Web site 1. All superpositions are visualised at the same source. Additional conformers (110,000 of 2400 classified WHO-drugs are also available.

    8. Hedgehog pathway as a drug target: Smoothened inhibitors in development

      Directory of Open Access Journals (Sweden)

      Lin TL

      2012-03-01

      Full Text Available Tara L Lin1, William Matsui21Division of Hematology/Oncology, Department of Internal Medicine, University of Kansas, Kansas City, MO, USA; 2Division of Hematologic Malignancies, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USAAbstract: Emerging laboratory and clinical investigations demonstrate that Hedgehog signaling (Hh represents a novel therapeutic target in various human cancers. This conserved signaling pathway precisely regulates self-renewal and terminal differentiation in embryonic development, but is typically silenced in adult tissues, with reactivation usually only during tissue repair. Aberrant Hh pathway signaling has been implicated in the pathogenesis, self-renewal, and chemotherapy resistance of a growing number of solid and hematologic malignancies. Major components of the Hh pathway include the Hh ligands (Sonic, Desert, and Indian, the transmembrane receptor Patched, the signal transducer Smoothened (Smo, and transcription factors Gli1–3 which regulate the transcription of Hh target genes. Mutations in Hh pathway genes, increased Hh signaling in tumor stroma, and Hh overexpression in self-renewing cells (cancer stem cells have been described, and these different modes of Hh signaling have implications for the design of Hh pathway inhibitors and their integration into conventional treatment regimens. Discovery of a naturally-occurring Smo inhibitor, cyclopamine, and the identification of Hh pathway mutations and over expression in cancer cells prompted the development of several cyclopamine derivatives. Encouraging laboratory and in vivo data has resulted in Phase I and II clinical trials of Smo inhibitors. In this review, we will discuss the current understanding of Hh pathway signaling in malignancy and Smo antagonists in development. Recent data with these agents shows that they are well-tolerated and may be effective for subsets of patients. Challenges remain

    9. Inhibition of Glutamine Synthetase: A Potential Drug Target in Mycobacterium tuberculosis

      Directory of Open Access Journals (Sweden)

      Sherry L. Mowbray

      2014-08-01

      Full Text Available Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis. Globally, tuberculosis is second only to AIDS in mortality and the disease is responsible for over 1.3 million deaths each year. The impractically long treatment schedules (generally 6–9 months and unpleasant side effects of the current drugs often lead to poor patient compliance, which in turn has resulted in the emergence of multi-, extensively- and totally-drug resistant strains. The development of new classes of anti-tuberculosis drugs and new drug targets is of global importance, since attacking the bacterium using multiple strategies provides the best means to prevent resistance. This review presents an overview of the various strategies and compounds utilized to inhibit glutamine synthetase, a promising target for the development of drugs for TB therapy.

    10. Target engagement and drug residence time can be observed in living cells with BRET.

      Science.gov (United States)

      Robers, Matthew B; Dart, Melanie L; Woodroofe, Carolyn C; Zimprich, Chad A; Kirkland, Thomas A; Machleidt, Thomas; Kupcho, Kevin R; Levin, Sergiy; Hartnett, James R; Zimmerman, Kristopher; Niles, Andrew L; Ohana, Rachel Friedman; Daniels, Danette L; Slater, Michael; Wood, Monika G; Cong, Mei; Cheng, Yi-Qiang; Wood, Keith V

      2015-12-03

      The therapeutic action of drugs is predicated on their physical engagement with cellular targets. Here we describe a broadly applicable method using bioluminescence resonance energy transfer (BRET) to reveal the binding characteristics of a drug with selected targets within intact cells. Cell-permeable fluorescent tracers are used in a competitive binding format to quantify drug engagement with the target proteins fused to Nanoluc luciferase. The approach enabled us to profile isozyme-specific engagement and binding kinetics for a panel of histone deacetylase (HDAC) inhibitors. Our analysis was directed particularly to the clinically approved prodrug FK228 (Istodax/Romidepsin) because of its unique and largely unexplained mechanism of sustained intracellular action. Analysis of the binding kinetics by BRET revealed remarkably long intracellular residence times for FK228 at HDAC1, explaining the protracted intracellular behaviour of this prodrug. Our results demonstrate a novel application of BRET for assessing target engagement within the complex milieu of the intracellular environment.

    11. Hyaluronic acid modified mesoporous carbon nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells

      Science.gov (United States)

      Wan, Long; Jiao, Jian; Cui, Yu; Guo, Jingwen; Han, Ning; Di, Donghua; Chang, Di; Wang, Pu; Jiang, Tongying; Wang, Siling

      2016-04-01

      In this paper, hyaluronic acid (HA) functionalized uniform mesoporous carbon spheres (UMCS) were synthesized for targeted enzyme responsive drug delivery using a facile electrostatic attraction strategy. This HA modification ensured stable drug encapsulation in mesoporous carbon nanoparticles in an extracellular environment while increasing colloidal stability, biocompatibility, cell-targeting ability, and controlled cargo release. The cellular uptake experiments of fluorescently labeled mesoporous carbon nanoparticles, with or without HA functionalization, demonstrated that HA-UMCS are able to specifically target cancer cells overexpressing CD44 receptors. Moreover, the cargo loaded doxorubicin (DOX) and verapamil (VER) exhibited a dual pH and hyaluronidase-1 responsive release in the tumor microenvironment. In addition, VER/DOX/HA-UMCS exhibited a superior therapeutic effect on an in vivo HCT-116 tumor in BALB/c nude mice. In summary, it is expected that HA-UMCS will offer a new method for targeted co-delivery of drugs to tumors overexpressing CD44 receptors.

    12. Recent discoveries of influenza A drug target sites to combat virus replication.

      Science.gov (United States)

      Patel, Hershna; Kukol, Andreas

      2016-06-15

      Sequence variations in the binding sites of influenza A proteins are known to limit the effectiveness of current antiviral drugs. Clinically, this leads to increased rates of virus transmission and pathogenicity. Potential influenza A inhibitors are continually being discovered as a result of high-throughput cell based screening studies, whereas the application of computational tools to aid drug discovery has further increased the number of predicted inhibitors reported. This review brings together the aspects that relate to the identification of influenza A drug target sites and the findings from recent antiviral drug discovery strategies. PMID:27284062

    13. A RNA-DNA Hybrid Aptamer for Nanoparticle-Based Prostate Tumor Targeted Drug Delivery

      Directory of Open Access Journals (Sweden)

      John C. Leach

      2016-03-01

      Full Text Available The side effects of radio- and chemo-therapy pose long-term challenges on a cancer patient’s health. It is, therefore, highly desirable to develop more effective therapies that can specifically target carcinoma cells without damaging normal and healthy cells. Tremendous efforts have been made in the past to develop targeted drug delivery systems for solid cancer treatment. In this study, a new aptamer, A10-3-J1, which recognizes the extracellular domain of the prostate specific membrane antigen (PSMA, was designed. A super paramagnetic iron oxide nanoparticle-aptamer-doxorubicin (SPIO-Apt-Dox was fabricated and employed as a targeted drug delivery platform for cancer therapy. This DNA RNA hybridized aptamer antitumor agent was able to enhance the cytotoxicity of targeted cells while minimizing collateral damage to non-targeted cells. This SPIO-Apt-Dox nanoparticle has specificity to PSMA+ prostate cancer cells. Aptamer inhibited nonspecific uptake of membrane-permeable doxorubic to the non-target cells, leading to reduced untargeted cytotoxicity and endocytic uptake while enhancing targeted cytotoxicity and endocytic uptake. The experimental results indicate that the drug delivery platform can yield statistically significant effectiveness being more cytotoxic to the targeted cells as opposed to the non-targeted cells.

    14. A RNA-DNA Hybrid Aptamer for Nanoparticle-Based Prostate Tumor Targeted Drug Delivery

      Science.gov (United States)

      Leach, John C.; Wang, Andrew; Ye, Kaiming; Jin, Sha

      2016-01-01

      The side effects of radio- and chemo-therapy pose long-term challenges on a cancer patient’s health. It is, therefore, highly desirable to develop more effective therapies that can specifically target carcinoma cells without damaging normal and healthy cells. Tremendous efforts have been made in the past to develop targeted drug delivery systems for solid cancer treatment. In this study, a new aptamer, A10-3-J1, which recognizes the extracellular domain of the prostate specific membrane antigen (PSMA), was designed. A super paramagnetic iron oxide nanoparticle-aptamer-doxorubicin (SPIO-Apt-Dox) was fabricated and employed as a targeted drug delivery platform for cancer therapy. This DNA RNA hybridized aptamer antitumor agent was able to enhance the cytotoxicity of targeted cells while minimizing collateral damage to non-targeted cells. This SPIO-Apt-Dox nanoparticle has specificity to PSMA+ prostate cancer cells. Aptamer inhibited nonspecific uptake of membrane-permeable doxorubic to the non-target cells, leading to reduced untargeted cytotoxicity and endocytic uptake while enhancing targeted cytotoxicity and endocytic uptake. The experimental results indicate that the drug delivery platform can yield statistically significant effectiveness being more cytotoxic to the targeted cells as opposed to the non-targeted cells. PMID:26985893

    15. In-silico prediction of drug targets, biological activities, signal pathways and regulating networks of dioscin based on bioinformatics

      OpenAIRE

      Yin, Lianhong; Zheng, Lingli; Xu, Lina; Dong, Deshi; Han, Xu; Qi, Yan; Zhao, Yanyan; Xu, Youwei; Peng, Jinyong

      2015-01-01

      Background Inverse docking technology has been a trend of drug discovery, and bioinformatics approaches have been used to predict target proteins, biological activities, signal pathways and molecular regulating networks affected by drugs for further pharmacodynamic and mechanism studies. Methods In the present paper, inverse docking technology was applied to screen potential targets from potential drug target database (PDTD). Then, the corresponding gene information of the obtained drug-targe...

    16. Specific Cell Targeting Therapy Bypasses Drug Resistance Mechanisms in African Trypanosomiasis

      Science.gov (United States)

      Unciti-Broceta, Juan D.; Arias, José L.; Maceira, José; Soriano, Miguel; Ortiz-González, Matilde; Hernández-Quero, José; Muñóz-Torres, Manuel; de Koning, Harry P.; Magez, Stefan; Garcia-Salcedo, José A.

      2015-01-01

      African trypanosomiasis is a deadly neglected disease caused by the extracellular parasite Trypanosoma brucei. Current therapies are characterized by high drug toxicity and increasing drug resistance mainly associated with loss-of-function mutations in the transporters involved in drug import. The introduction of new antiparasitic drugs into therapeutic use is a slow and expensive process. In contrast, specific targeting of existing drugs could represent a more rapid and cost-effective approach for neglected disease treatment, impacting through reduced systemic toxicity and circumventing resistance acquired through impaired compound uptake. We have generated nanoparticles of chitosan loaded with the trypanocidal drug pentamidine and coated by a single domain nanobody that specifically targets the surface of African trypanosomes. Once loaded into this nanocarrier, pentamidine enters trypanosomes through endocytosis instead of via classical cell surface transporters. The curative dose of pentamidine-loaded nanobody-chitosan nanoparticles was 100-fold lower than pentamidine alone in a murine model of acute African trypanosomiasis. Crucially, this new formulation displayed undiminished in vitro and in vivo activity against a trypanosome cell line resistant to pentamidine as a result of mutations in the surface transporter aquaglyceroporin 2. We conclude that this new drug delivery system increases drug efficacy and has the ability to overcome resistance to some anti-protozoal drugs. PMID:26110623

    17. Antibacterial Drug Leads: DNA and Enzyme Multi-Targeting

      Science.gov (United States)

      Zhu, Wei; Wang, Yang; Li, Kai; Gao, Jian; Huang, Chun-Hsiang; Chen, Chun-Chi; Ko, Tzu-Ping; Zhang, Yonghui; Guo, Rey-Ting; Oldfield, Eric

      2015-01-01

      We report the results of an investigation of the activity of a series of amidine and bisamidine compounds against Staphylococcus aureus and Escherichia coli. The most active compounds bound to an AT-rich DNA dodecamer (CGCGAATTCGCG)2, and using DSC were found to increase the melting transition by up to 24 °C. Several compounds also inhibited undecaprenyl diphosphate synthase (UPPS) with IC50 values of 100–500 nM and we found good correlations (R2 = 0.89, S. aureus; R2 = 0.79, E. coli)) between experimental and predicted cell growth inhibition by using DNA ΔTm and UPPS IC50 experimental results together with 1 computed descriptor. We also solved the structures of three bisamidines binding to DNA as well as three UPPS structures. Overall, the results are of general interest in the context of the development of resistance-resistant antibiotics that involve multi-targeting. PMID:25574764

    18. Signaling pathways relevant to cognition-enhancing drug targets.

      Science.gov (United States)

      Ménard, Caroline; Gaudreau, Pierrette; Quirion, Rémi

      2015-01-01

      Aging is generally associated with a certain cognitive decline. However, individual differences exist. While age-related memory deficits can be observed in humans and rodents in the absence of pathological conditions, some individuals maintain intact cognitive functions up to an advanced age. The mechanisms underlying learning and memory processes involve the recruitment of multiple signaling pathways and gene expression, leading to adaptative neuronal plasticity and long-lasting changes in brain circuitry. This chapter summarizes the current understanding of how these signaling cascades could be modulated by cognition-enhancing agents favoring memory formation and successful aging. It focuses on data obtained in rodents, particularly in the rat as it is the most common animal model studied in this field. First, we will discuss the role of the excitatory neurotransmitter glutamate and its receptors, downstream signaling effectors [e.g., calcium/calmodulin-dependent protein kinase II (CaMKII), protein kinase C (PKC), extracellular signal-regulated kinases (ERK), mammalian target of rapamycin (mTOR), cAMP response element-binding protein (CREB)], associated immediate early gene (e.g., Homer 1a, Arc and Zif268), and growth factors [insulin-like growth factors (IGFs) and brain-derived neurotrophic factor (BDNF)] in synaptic plasticity and memory formation. Second, the impact of the cholinergic system and related modulators on memory will be briefly reviewed. Finally, since dynorphin neuropeptides have recently been associated with memory impairments in aging, it is proposed as an attractive target to develop novel cognition-enhancing agents. PMID:25977080

    19. Imaging of a targeted PDT drug with fluorescence tomography

      Science.gov (United States)

      Muffoletto, Dan; Gupta, Anurag; Xu, Zhiqiang; Mahrer, Chris; Bauer, Gretchen; Galas, Scott; Pandey, Ravindra K.; Sunar, Ulas

      2009-02-01

      We constructed a whole-body fluorescence tomography instrument to monitor novel bifunctional phototherapeutic drugs (e.g., HPPH-Cyanine dye conjugate) in small animals. The instrument allows dense source and detector sampling with a fast galvo scanner and a CCD detector for improved resolution and sensitivity (Patwardhan et al., 2005). Here we report tissue phantom measurements to evaluate the imaging performance with a newly constructed tomography instrument. Phantom measurements showed that strong fluorescence generated by HPPH-Cyanine dye (HPPH-CD), having high fluorescence quantum yield and long wavelength fluorescence emission, allowed deep tissue imaging. We also report in vivo fluorescence measurements of the conjugate in Nude mice bearing A549 human non-small cell lung carcinoma (NSCLC) tumors at 24 hr post injection to evaluate tumor detection ability of the conjugate. Our results indicate that the HPPH-CD shows preferential uptake in tumors compared to surrounding normal tissue at 24 hr post injection. This study demonstrates a potential use of HPPH-CD in detection (fluorescence imaging) and treatment (PDT) of deeply seated tumors.

    20. Epigenetic Modifications, Alcoholic Brain and Potential Drug Targets

      Science.gov (United States)

      Jangra, Ashok; Sriram, Chandra Shaker; Pandey, Suryanarayan; Choubey, Priyansha; Rajput, Prabha; Saroha, Babita; Bezbaruah, Babul Kumar; Lahkar, Mangala

      2016-01-01

      Acute and chronic alcohol exposure evidently influences epigenetic changes, both transiently and permanently, and these changes in turn influence a variety of cells and organ systems throughout the body. Many of the alcohol-induced epigenetic modifications can contribute to cellular adaptations that ultimately lead to behavioral tolerance and alcohol dependence. The persistence of behavioral changes demonstrates that long-lasting changes in gene expression, within particular regions of the brain, may contribute importantly to the addiction phenotype. The research activities over the past years have demonstrated a crucial role of epigenetic mechanisms in causing long lasting and transient changes in the expression of several genes in diverse tissues, including brain. This has stimulated recent research work that is aimed at characterizing the influence of epigenetic regulatory events in mediating the long lasting and transient effects of alcohol abuse on the brain in humans and animal models of alcohol addiction. In this study, we update our current understanding of the impact of alcohol exposure on epigenetic mechanisms in the brain and refurbish the knowledge of epigenetics in the direction of new drugs development. PMID:27780992

    1. Novel drug designing rationale againstBrugia malayi microfilariae using herbal extracts

      Institute of Scientific and Technical Information of China (English)

      SharmaRD; PetareS; ShindeGB; KalyanGoswami; ReddyMVR

      2010-01-01

      Objective:To explore the effect of herbal polyphenolics on filariasisin vitro.Methods: Two herbal extracts, methanolic extracts of roots ofVitex negundo Linn. (Nirgundi) and leaves ofAegle marmelos Juss. (Beal) in different concentrations ranging from40-80ng/mL were tested for their antifilarial activity either alone or in combination with diethyl carbonate (DEC)(300μg/mL) and/orH2O2 (0.5 mM).Results:Combination of DEC and each extract had significant anti-filarial effect. And fractions of both extracts were not effective as crude herbal extract.Conclusions:Such unique pharmacodynamics reported in this study might provide new drug development stratagem against filariasis.

    2. Polysaccharide-based micro/nanocarriers for oral colon-targeted drug delivery.

      Science.gov (United States)

      Zhang, Lin; Sang, Yuan; Feng, Jing; Li, Zhaoming; Zhao, Aili

      2016-08-01

      Oral colon-targeted drug delivery has attracted many researchers because of its distinct advantages of increasing the bioavailability of the drug at the target site and reducing the side effects. Polysaccharides that are precisely activated by the physiological environment of the colon hold greater promise for colon targeting. Considerable research efforts have been directed towards developing polysaccharide-based micro/nanocarriers. Types of polysaccharides for colon targeting and in vitro/in vivo assessments of polysaccharide-based carriers for oral colon-targeted drug delivery are summarised. Polysaccharide-based microspheres have gained increased importance not just for the delivery of the drugs for the treatment of local diseases associated with the colon (colon cancer, inflammatory bowel disease (IBD), amoebiasis and irritable bowel syndrome (IBS)), but also for it's potential for the delivery of anti-rheumatoid arthritis and anti-chronic stable angina drugs. Besides, Polysaccharide-based micro/nanocarriers such as microbeads, microcapsules, microparticles, nanoparticles, nanogels and nanospheres are also introduced in this review. PMID:26766303

    3. From drug response profiling to target addiction scoring in cancer cell models

      Directory of Open Access Journals (Sweden)

      Bhagwan Yadav

      2015-10-01

      Full Text Available Deconvoluting the molecular target signals behind observed drug response phenotypes is an important part of phenotype-based drug discovery and repurposing efforts. We demonstrate here how our network-based deconvolution approach, named target addiction score (TAS, provides insights into the functional importance of druggable protein targets in cell-based drug sensitivity testing experiments. Using cancer cell line profiling data sets, we constructed a functional classification across 107 cancer cell models, based on their common and unique target addiction signatures. The pan-cancer addiction correlations could not be explained by the tissue of origin, and only correlated in part with molecular and genomic signatures of the heterogeneous cancer cells. The TAS-based cancer cell classification was also shown to be robust to drug response data resampling, as well as predictive of the transcriptomic patterns in an independent set of cancer cells that shared similar addiction signatures with the 107 cancers. The critical protein targets identified by the integrated approach were also shown to have clinically relevant mutation frequencies in patients with various cancer subtypes, including not only well-established pan-cancer genes, such as PTEN tumor suppressor, but also a number of targets that are less frequently mutated in specific cancer types, including ABL1 oncoprotein in acute myeloid leukemia. An application to leukemia patient primary cell models demonstrated how the target deconvolution approach offers functional insights into patient-specific addiction patterns, such as those indicative of their receptor-type tyrosine-protein kinase FLT3 internal tandem duplication (FLT3-ITD status and co-addiction partners, which may lead to clinically actionable, personalized drug treatment developments. To promote its application to the future drug testing studies, we have made available an open-source implementation of the TAS calculation in the form

    4. Predicting Molecular Targets for Small-Molecule Drugs with a Ligand-Based Interaction Fingerprint Approach.

      Science.gov (United States)

      Cao, Ran; Wang, Yanli

      2016-06-20

      The computational prediction of molecular targets for small-molecule drugs remains a great challenge. Herein we describe a ligand-based interaction fingerprint (LIFt) approach for target prediction. Together with physics-based docking and sampling methods, we assessed the performance systematically by modeling the polypharmacology of 12 kinase inhibitors in three stages. First, we examined the capacity of this approach to differentiate true targets from false targets with the promiscuous binder staurosporine, based on native complex structures. Second, we performed large-scale profiling of kinase selectivity on the clinical drug sunitinib by means of computational simulation. Third, we extended the study beyond kinases by modeling the cross-inhibition of bromodomain-containing protein 4 (BRD4) for 10 well-established kinase inhibitors. On this basis, we made prospective predictions by exploring new kinase targets for the anticancer drug candidate TN-16, originally known as a colchicine site binder and microtubule disruptor. As a result, p38α was highlighted from a panel of 187 different kinases. Encouragingly, our prediction was validated by an in vitro kinase assay, which showed TN-16 as a low-micromolar p38α inhibitor. Collectively, our results suggest the promise of the LIFt approach in predicting potential targets for small-molecule drugs. PMID:26222196

    5. Identifying co-targets to fight drug resistance based on a random walk model

      Directory of Open Access Journals (Sweden)

      Chen Liang-Chun

      2012-01-01

      Full Text Available Abstract Background Drug resistance has now posed more severe and emergent threats to human health and infectious disease treatment. However, wet-lab approaches alone to counter drug resistance have so far still achieved limited success due to less knowledge about the underlying mechanisms of drug resistance. Our approach apply a heuristic search algorithm in order to extract active network under drug treatment and use a random walk model to identify potential co-targets for effective antibacterial drugs. Results We use interactome network of Mycobacterium tuberculosis and gene expression data which are treated with two kinds of antibiotic, Isoniazid and Ethionamide as our test data. Our analysis shows that the active drug-treated networks are associated with the trigger of fatty acid metabolism and synthesis and nicotinamide adenine dinucleotide (NADH-related processes and those results are consistent with the recent experimental findings. Efflux pumps processes appear to be the major mechanisms of resistance but SOS response is significantly up-regulation under Isoniazid treatment. We also successfully identify the potential co-targets with literature confirmed evidences which are related to the glycine-rich membrane, adenosine triphosphate energy and cell wall processes. Conclusions With gene expression and interactome data supported, our study points out possible pathways leading to the emergence of drug resistance under drug treatment. We develop a computational workflow for giving new insights to bacterial drug resistance which can be gained by a systematic and global analysis of the bacterial regulation network. Our study also discovers the potential co-targets with good properties in biological and graph theory aspects to overcome the problem of drug resistance.

    6. ‘VIROSOMES’ A NOVEL STRATEGY FOR DELIVERY OF DRUGS AND TARGETING: AN OVERVIEW

      Directory of Open Access Journals (Sweden)

      M. Gowtham

      2012-10-01

      Full Text Available Over the years there has been a great revolution in drug delivery technologies. Virosomes drug delivery systems are an example of the various novel drug delivery systems available. A virosome is a drug or vaccine delivery mechanism consisting of unilamellar phospholipid bilayer vesicle incorporating virus derived proteins to allow the virosomes to fuse with target cells. Virosomes are not able to replicate but are pure fusion-active vesicle. These are reconstituted viral envelopes that can serve as vaccines and as vehicles for cellular delivery of macromolecules. The prospect of drug delivery and targeting using virosomes is an interesting field of research and development. Because virosomes are biocompatible, biodegradable, nontoxic, and non-autoimmunogenic, attempts have been made to use them as vaccines or adjuvants as well as delivery systems for drugs, nucleic acids, or genes for therapeutic purposes. The success of virosomal drug delivery depends on the methods used to prepare the encapsulated bioactive materials and incorporate them into the virosomes, as are characterization and formulation of the finished preparation. This article gives an insight of virosomes as a newer method of drug delivery. This article gives an insight of hydrogels and virosomes as a newer futuristic tool.

    7. Prediction of Effective Drug Combinations by Chemical Interaction, Protein Interaction and Target Enrichment of KEGG Pathways

      Directory of Open Access Journals (Sweden)

      Lei Chen

      2013-01-01

      Full Text Available Drug combinatorial therapy could be more effective in treating some complex diseases than single agents due to better efficacy and reduced side effects. Although some drug combinations are being used, their underlying molecular mechanisms are still poorly understood. Therefore, it is of great interest to deduce a novel drug combination by their molecular mechanisms in a robust and rigorous way. This paper attempts to predict effective drug combinations by a combined consideration of: (1 chemical interaction between drugs, (2 protein interactions between drugs’ targets, and (3 target enrichment of KEGG pathways. A benchmark dataset was constructed, consisting of 121 confirmed effective combinations and 605 random combinations. Each drug combination was represented by 465 features derived from the aforementioned three properties. Some feature selection techniques, including Minimum Redundancy Maximum Relevance and Incremental Feature Selection, were adopted to extract the key features. Random forest model was built with its performance evaluated by 5-fold cross-validation. As a result, 55 key features providing the best prediction result were selected. These important features may help to gain insights into the mechanisms of drug combinations, and the proposed prediction model could become a useful tool for screening possible drug combinations.

    8. Computational and Pharmacological Target of Neurovascular Unit for Drug Design and Delivery

      Directory of Open Access Journals (Sweden)

      Md. Mirazul Islam

      2015-01-01

      Full Text Available The blood-brain barrier (BBB is a dynamic and highly selective permeable interface between central nervous system (CNS and periphery that regulates the brain homeostasis. Increasing evidences of neurological disorders and restricted drug delivery process in brain make BBB as special target for further study. At present, neurovascular unit (NVU is a great interest and highlighted topic of pharmaceutical companies for CNS drug design and delivery approaches. Some recent advancement of pharmacology and computational biology makes it convenient to develop drugs within limited time and affordable cost. In this review, we briefly introduce current understanding of the NVU, including molecular and cellular composition, physiology, and regulatory function. We also discuss the recent technology and interaction of pharmacogenomics and bioinformatics for drug design and step towards personalized medicine. Additionally, we develop gene network due to understand NVU associated transporter proteins interactions that might be effective for understanding aetiology of neurological disorders and new target base protective therapies development and delivery.

    9. Iontophoresis of minoxidil sulphate loaded microparticles, a strategy for follicular drug targeting?

      Science.gov (United States)

      Gelfuso, Guilherme M; Barros, M Angélica de Oliveira; Delgado-Charro, M Begoña; Guy, Richard H; Lopez, Renata F V

      2015-10-01

      The feasibility of targeting drugs to hair follicles by a combination of microencapsulation and iontophoresis has been evaluated. Minoxidil sulphate (MXS), which is used in the treatment of alopecia, was selected as a relevant drug with respect to follicular penetration. The skin permeation and disposition of MXS encapsulated in chitosan microparticles (MXS-MP) was evaluated in vitro after passive and iontophoretic delivery. Uptake of MXS was quantified at different exposure times in the stratum corneum (SC) and hair follicles. Microencapsulation resulted in increased (6-fold) drug accumulation in the hair follicles relative to delivery from a simple MXS solution. Application of iontophoresis enhanced follicular delivery for both the solution and the microparticle formulations. It appears, therefore, that microencapsulation and iontophoresis can act synergistically to enhance topical drug targeting to hair follicles.

    10. Nanotechnology-based drug delivery treatments and specific targeting therapy for age-related macular degeneration.

      Science.gov (United States)

      Lin, Tai-Chi; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Liu, Jorn-Hon; Woung, Lin-Chung; Tsai, Ching-Yao; Chen, Shih-Jen; Chen, Yan-Ting; Hsu, Chih-Chien

      2015-11-01

      Nanoparticles combined with cells, drugs, and specially designed genes provide improved therapeutic efficacy in studies and clinical setting, demonstrating a new era of treatment strategy, especially in retinal diseases. Nanotechnology-based drugs can provide an essential platform for sustaining, releasing and a specific targeting design to treat retinal diseases. Poly-lactic-co-glycolic acid is the most widely used biocompatible and biodegradable polymer approved by the Food and Drug Administration. Many studies have attempted to develop special devices for delivering small-molecule drugs, proteins, and other macromolecules consistently and slowly. In this article, we first review current progress in the treatment of age-related macular degeneration. Then, we discuss the function of vascular endothelial growth factor (VEGF) and the pharmacological effects of anti-VEGF-A antibodies and soluble or modified VEGF receptors. Lastly, we summarize the combination of antiangiogenic therapy and nanomedicines, and review current potential targeting therapy in age-related macular degeneration.

    11. Iontophoresis of minoxidil sulphate loaded microparticles, a strategy for follicular drug targeting?

      Science.gov (United States)

      Gelfuso, Guilherme M; Barros, M Angélica de Oliveira; Delgado-Charro, M Begoña; Guy, Richard H; Lopez, Renata F V

      2015-10-01

      The feasibility of targeting drugs to hair follicles by a combination of microencapsulation and iontophoresis has been evaluated. Minoxidil sulphate (MXS), which is used in the treatment of alopecia, was selected as a relevant drug with respect to follicular penetration. The skin permeation and disposition of MXS encapsulated in chitosan microparticles (MXS-MP) was evaluated in vitro after passive and iontophoretic delivery. Uptake of MXS was quantified at different exposure times in the stratum corneum (SC) and hair follicles. Microencapsulation resulted in increased (6-fold) drug accumulation in the hair follicles relative to delivery from a simple MXS solution. Application of iontophoresis enhanced follicular delivery for both the solution and the microparticle formulations. It appears, therefore, that microencapsulation and iontophoresis can act synergistically to enhance topical drug targeting to hair follicles. PMID:26222406

    12. Drug Target Optimization in Chronic Myeloid Leukemia Using Innovative Computational Platform

      Science.gov (United States)

      Chuang, Ryan; Hall, Benjamin A.; Benque, David; Cook, Byron; Ishtiaq, Samin; Piterman, Nir; Taylor, Alex; Vardi, Moshe; Koschmieder, Steffen; Gottgens, Berthold; Fisher, Jasmin

      2015-02-01

      Chronic Myeloid Leukemia (CML) represents a paradigm for the wider cancer field. Despite the fact that tyrosine kinase inhibitors have established targeted molecular therapy in CML, patients often face the risk of developing drug resistance, caused by mutations and/or activation of alternative cellular pathways. To optimize drug development, one needs to systematically test all possible combinations of drug targets within the genetic network that regulates the disease. The BioModelAnalyzer (BMA) is a user-friendly computational tool that allows us to do exactly that. We used BMA to build a CML network-model composed of 54 nodes linked by 104 interactions that encapsulates experimental data collected from 160 publications. While previous studies were limited by their focus on a single pathway or cellular process, our executable model allowed us to probe dynamic interactions between multiple pathways and cellular outcomes, suggest new combinatorial therapeutic targets, and highlight previously unexplored sensitivities to Interleukin-3.

    13. Progress and Challenges in Developing Aptamer-Functionalized Targeted Drug Delivery Systems.

      Science.gov (United States)

      Jiang, Feng; Liu, Biao; Lu, Jun; Li, Fangfei; Li, Defang; Liang, Chao; Dang, Lei; Liu, Jin; He, Bing; Badshah, Shaikh Atik; Lu, Cheng; He, Xiaojuan; Guo, Baosheng; Zhang, Xiao-Bing; Tan, Weihong; Lu, Aiping; Zhang, Ge

      2015-01-01

      Aptamers, which can be screened via systematic evolution of ligands by exponential enrichment (SELEX), are superior ligands for molecular recognition due to their high selectivity and affinity. The interest in the use of aptamers as ligands for targeted drug delivery has been increasing due to their unique advantages. Based on their different compositions and preparation methods, aptamer-functionalized targeted drug delivery systems can be divided into two main categories: aptamer-small molecule conjugated systems and aptamer-nanomaterial conjugated systems. In this review, we not only summarize recent progress in aptamer selection and the application of aptamers in these targeted drug delivery systems but also discuss the advantages, challenges and new perspectives associated with these delivery systems.

    14. Recent advances in lymphatic targeted drug deliver y system for tumor metastasis

      Institute of Scientific and Technical Information of China (English)

      Xiao-Yu Zhang; Wei-Yue Lu

      2014-01-01

      Te lymphatic system has an important defensive role in the human body. hTe metastasis of most tumors initially spreads through the surrounding lymphatic tissue and eventually forms lymphatic metastatic tumors;the tumor cells may even transfer to other organs to form other types of tumors. Clinically, lymphatic metastatic tumors develop rapidly. Given the limitations of surgical resection and the low effectiveness of radiotherapy and chemotherapy, the treatment of lymphatic metastatic tumors remains a great challenge. Lymph node metastasis may lead to the further spread of tumors and may be predictive of the endpoint event. Under these circumstances, novel and effective lymphatic targeted drug delivery systems have been explored to improve the speciifcity of anticancer drugs to tumor cells in lymph nodes. In this review, we summarize the principles of lymphatic targeted drug delivery and discuss recent advances in the development of lymphatic targeted carriers.

    15. Progress and Challenges in Developing Aptamer-Functionalized Targeted Drug Delivery Systems

      Directory of Open Access Journals (Sweden)

      Feng Jiang

      2015-10-01

      Full Text Available Aptamers, which can be screened via systematic evolution of ligands by exponential enrichment (SELEX, are superior ligands for molecular recognition due to their high selectivity and affinity. The interest in the use of aptamers as ligands for targeted drug delivery has been increasing due to their unique advantages. Based on their different compositions and preparation methods, aptamer-functionalized targeted drug delivery systems can be divided into two main categories: aptamer-small molecule conjugated systems and aptamer-nanomaterial conjugated systems. In this review, we not only summarize recent progress in aptamer selection and the application of aptamers in these targeted drug delivery systems but also discuss the advantages, challenges and new perspectives associated with these delivery systems.

    16. Muscarinic Acetylcholine Receptor Subtypes as Potential Drug Targets for the Treatment of Schizophrenia, Drug Abuse and Parkinson's Disease

      DEFF Research Database (Denmark)

      Dencker, Ditte; Thomsen, Morgane; Wörtwein, Gitta;

      2011-01-01

      's disease and drug abuse. Dopaminergic systems are regulated by cholinergic, especially muscarinic, input. Not surprisingly, increasing evidence implicates muscarinic acetylcholine receptor-mediated pathways as potential targets for the treatment of these disorders classically viewed as "dopamine based...... muscarinic receptor subtypes have greatly advanced our knowledge of the physiological roles of the M(1)-M(5) receptors. Recently, new ligands have been developed that can interact with allosteric sites on different muscarinic receptor subtypes, rather than the conventional (orthosteric) acetylcholine binding...

    17. Multidrug resistance in oncology and beyond : from imaging of drug efflux pumps to cellular drug targets

      NARCIS (Netherlands)

      Nagengast, Wouter B; Oude Munnink, Thijs H; Dijkers, Eli; Hospers, Geesiena; Brouwers, Adrienne H; Schröder, Carolien P; Lub-de Hooge, Marjolijn; de Vries, Elisabeth G E

      2010-01-01

      Resistance of tumor cells to several structurally unrelated classes of natural products, including anthracyclines, taxanes, and epipodophyllotoxines, is often referred as multidrug resistance (MDR). This is associated with ATP-binding cassette transporters, which function as drug efflux pumps such a

    18. Pluronic F127 nanomicelles engineered with nuclear localized functionality for targeted drug delivery

      Energy Technology Data Exchange (ETDEWEB)

      Li, Yong-Yong; Li, Lan; Dong, Hai-Qing, E-mail: inano_donghq@tongji.edu.cn; Cai, Xiao-Jun; Ren, Tian-Bin, E-mail: rentianbin@yeah.net

      2013-07-01

      PKKKRKV (Pro-Lys-Lys-Lys-Arg-Lys-Val, PV7), a seven amino acid peptide, has emerged as one of the primary nuclear localization signals that can be targeted into cell nucleus via the nuclear import machinery. Taking advantage of chemical diversity and biological activities of this short peptide sequence, in this study, Pluronic F127 nanomicelles engineered with nuclear localized functionality were successfully developed for intracellular drug delivery. These nanomicelles with the size ∼ 100 nm were self-assembled from F127 polymer that was flanked with two PV7 sequences at its both terminal ends. Hydrophobic anticancer drug doxorubicin (DOX) with inherent fluorescence was chosen as the model drug, which was found to be efficiently encapsulated into nanomicelles with the encapsulation efficiency at 72.68%. In comparison with the non-functionalized namomicelles, the microscopic observation reveals that PV7 functionalized nanomicelles display a higher cellular uptake, especially into the nucleus of HepG2 cells, due to the nuclear localization signal effects. Both cytotoxicity and apoptosis studies show that the DOX-loaded nanomicelles were more potent than drug nanomicelles without nuclear targeting functionality. It was thus concluded that PV7 functionalized nanomicelles could be a potentially alternative vehicle for nuclear targeting drug delivery. - Highlights: ► A new nuclear targeted drug delivery system based on micelles is developed. ► This micellar system features a core-shell structure with the size peaked at 100 nm. ► PV7, a short peptide sequence, is adopted as a nuclear targeting ligand. ► PV7 functionalized drug loaded micelles are more potent in killing tumor cells.

    19. Is the beta3-adrenoceptor (ADRB3) a potential target for uterorelaxant drugs?

      OpenAIRE

      2007-01-01

      The management of premature birth still remains unsatisfactory. Since the relative lack of efficiency and/or safety of current tocolytic agents have been highlighted, it is necessary to develop new uterorelaxant drugs deprived of important maternal and foetal side effects. Our work reported in this review focuses on a potential new target for tocolytic drugs, the beta3-adrenoceptor (ADRB3). This third type of ADRB is shown to be present and functional in human myometrium. We demonstrated that...

    20. Identification of new drug targets and resistance mechanisms in Mycobacterium tuberculosis.

      Directory of Open Access Journals (Sweden)

      Thomas R Ioerger

      Full Text Available Identification of new drug targets is vital for the advancement of drug discovery against Mycobacterium tuberculosis, especially given the increase of resistance worldwide to first- and second-line drugs. Because traditional target-based screening has largely proven unsuccessful for antibiotic discovery, we have developed a scalable platform for target identification in M. tuberculosis that is based on whole-cell screening, coupled with whole-genome sequencing of resistant mutants and recombineering to confirm. The method yields targets paired with whole-cell active compounds, which can serve as novel scaffolds for drug development, molecular tools for validation, and/or as ligands for co-crystallization. It may also reveal other information about mechanisms of action, such as activation or efflux. Using this method, we identified resistance-linked genes for eight compounds with anti-tubercular activity. Four of the genes have previously been shown to be essential: AspS, aspartyl-tRNA synthetase, Pks13, a polyketide synthase involved in mycolic acid biosynthesis, MmpL3, a membrane transporter, and EccB3, a component of the ESX-3 type VII secretion system. AspS and Pks13 represent novel targets in protein translation and cell-wall biosynthesis. Both MmpL3 and EccB3 are involved in membrane transport. Pks13, AspS, and EccB3 represent novel candidates not targeted by existing TB drugs, and the availability of whole-cell active inhibitors greatly increases their potential for drug discovery.

    1. Studies in Multifunctional Drug Development: Preparation and Evaluation of 11beta-Substituted Estradiol-Drug Conjugates, Cell Membrane Targeting Imaging Agents, and Target Multifunctional Nanoparticles

      Science.gov (United States)

      Dao, KinhLuan Lenny D.

      Cancer is the second leading cause of death after cardiovascular disease in the United State. Despite extensive research in development of antitumor drugs, most of these therapeutic entities often possess nonspecific toxicity, thus they can only be used to treat tumors in higher doses or more frequently. Because of the cytotoxicity and severe side effects, the drug therapeutic window normally is limited. Beside the toxicity issue, antitumor drug are also not selectively taken up by tumor cells, thus the necessitating concentrations that would eradicate the tumor can often not be used. In addition, tumor cells tend to develop resistance against the anticancer drugs after prolonged treatment. Therefore, alleviating the systemic cytotoxicity and side effects, improving in tumor selectivity, high potency, and therapeutic efficacy are still major obstacles in the area of anticancer drug development. A more promising approach for developing a selective agent for cancer is to conjugate a potent therapeutic drug, or an imaging agent with a targeting group, such as antibody or a high binding-specificity small molecule, that selectively recognize the overexpressed antigens or proteins on tumor cells. My research combines several approaches to describe this strategy via using different targeting molecules to different diseases, as well as different potent cytotoxic drugs for different therapies. Three studies related to the preparation and biological evaluation of new therapeutic agents, such as estradiol-drug hybrids, cell membrane targeted molecular imaging agents, and multifunctional NPs will be discussed. The preliminary results of these studies indicated that our new reagents achieved their initial objectives and can be further improved for optimized synthesis and in vivo experiments. The first study describes the method in which we employed a modular assembly approach to synthesize a novel 11beta-substituted steroidal anti-estrogen. The key intermediate was synthesized

    2. High concentrations of drug in target tissues following local controlled release are utilized for both drug distribution and biologic effect: an example with epicardial inotropic drug delivery.

      Science.gov (United States)

      Maslov, Mikhail Y; Edelman, Elazer R; Wei, Abraham E; Pezone, Matthew J; Lovich, Mark A

      2013-10-28

      Local drug delivery preferentially loads target tissues with a concentration gradient from the surface or point of release that tapers down to more distant sites. Drug that diffuses down this gradient must be in unbound form, but such drug can only elicit a biologic effect through receptor interactions. Drug excess loads tissues, increasing gradients and driving penetration, but with limited added biological response. We examined the hypothesis that local application reduces dramatically systemic circulating drug levels but leads to significantly higher tissue drug concentration than might be needed with systemic infusion in a rat model of local epicardial inotropic therapy. Epinephrine was infused systemically or released locally to the anterior wall of the heart using a novel polymeric platform that provides steady, sustained release over a range of precise doses. Epinephrine tissue concentration, upregulation of cAMP, and global left ventricular response were measured at equivalent doses and at doses equally effective in raising indices of contractility. The contractile stimulation by epinephrine was linked to drug tissue levels and commensurate cAMP upregulation for IV systemic infusion, but not with local epicardial delivery. Though cAMP was a powerful predictor of contractility with local application, tissue epinephrine levels were high and variable--only a small fraction of the deposited epinephrine was utilized in second messenger signaling and biologic effect. The remainder of deposited drug was likely used in diffusive transport and distribution. Systemic side effects were far more profound with IV infusion which, though it increased contractility, also induced tachycardia and loss of systemic vascular resistance, which were not seen with local application. Local epicardial inotropic delivery illustrates then a paradigm of how target tissues differentially handle and utilize drug compared to systemic infusion. PMID:23872515

    3. An inflammation-targeting hydrogel for local drug delivery in inflammatory bowel disease.

      Science.gov (United States)

      Zhang, Sufeng; Ermann, Joerg; Succi, Marc D; Zhou, Allen; Hamilton, Matthew J; Cao, Bonnie; Korzenik, Joshua R; Glickman, Jonathan N; Vemula, Praveen K; Glimcher, Laurie H; Traverso, Giovanni; Langer, Robert; Karp, Jeffrey M

      2015-08-12

      There is a clinical need for new, more effective treatments for chronic and debilitating inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. Targeting drugs selectively to the inflamed intestine may improve therapeutic outcomes and minimize systemic toxicity. We report the development of an inflammation-targeting hydrogel (IT-hydrogel) that acts as a drug delivery system to the inflamed colon. Hydrogel microfibers were generated from ascorbyl palmitate, an amphiphile that is generally recognized as safe (GRAS) by the U.S. Food and Drug Administration. IT-hydrogel microfibers loaded with the anti-inflammatory corticosteroid dexamethasone (Dex) were stable, released drug only upon enzymatic digestion, and demonstrated preferential adhesion to inflamed epithelial surfaces in vitro and in two mouse colitis models in vivo. Dex-loaded IT-hydrogel enemas, but not free Dex enemas, administered every other day to mice with colitis resulted in a significant reduction in inflammation and were associated with lower Dex peak serum concentrations and, thus, less systemic drug exposure. Ex vivo analysis of colon tissue samples from patients with ulcerative colitis demonstrated that IT-hydrogel microfibers adhered preferentially to mucosa from inflamed lesions compared with histologically normal sites. The IT-hydrogel drug delivery platform represents a promising approach for targeted enema-based therapies in patients with colonic IBD. PMID:26268315

    4. Multifunctional Micellar Nanocarriers for Tumor-Targeted Delivery of Hydrophobic Drugs.

      Science.gov (United States)

      Dai, Zhi; Tu, Ying; Zhu, Lin

      2016-06-01

      Poor water solubility, low tumor specificity, insufficient cell internalization, and drug resistance are typical among chemotherapy drugs. In this study, the multifunctional micellar nanocarriers containing the PEG2k-pp-PE, a matrix metalloproteinase 2 (MMP2)-labile self-assembling block copolymer, and the TAT-PEG1k-PE, a cell penetrating moiety, were developed for tumor-targeted delivery of hydrophobic drugs. The functional polymers and their nanocarriers were characterized in terms of their size, zeta potential, micelle formation capability, drug loading and release, cellular uptake, and anticancer activity. After the MMP2-mediated cleavage, the protective long chain PEG (PEG2k) was deshielded and the cell penetrating peptide (TAT) was exposed for the enhanced tumor targeting and cellular penetration. In the in vitro studies, the multifunctional nanocarriers showed the improved cellular uptake and anticancer activity in various cancer cells including both drug sensitive and resistant cells, compared to their nonsensitive counterparts and conventional polymeric micelles. Furthermore, the PEG2k-pp-PE and its containing micelles were found to possess the capability to reverse the P-glycoprotein-mediated multidrug resistance. Our results suggested that the multifunctional micellar nanocarriers would be a promising tumor-targeted drug delivery platform, applicable for the MMP2 up-regulated cancers. PMID:27319214

    5. An inflammation-targeting hydrogel for local drug delivery in inflammatory bowel disease.

      Science.gov (United States)

      Zhang, Sufeng; Ermann, Joerg; Succi, Marc D; Zhou, Allen; Hamilton, Matthew J; Cao, Bonnie; Korzenik, Joshua R; Glickman, Jonathan N; Vemula, Praveen K; Glimcher, Laurie H; Traverso, Giovanni; Langer, Robert; Karp, Jeffrey M

      2015-08-12

      There is a clinical need for new, more effective treatments for chronic and debilitating inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis. Targeting drugs selectively to the inflamed intestine may improve therapeutic outcomes and minimize systemic toxicity. We report the development of an inflammation-targeting hydrogel (IT-hydrogel) that acts as a drug delivery system to the inflamed colon. Hydrogel microfibers were generated from ascorbyl palmitate, an amphiphile that is generally recognized as safe (GRAS) by the U.S. Food and Drug Administration. IT-hydrogel microfibers loaded with the anti-inflammatory corticosteroid dexamethasone (Dex) were stable, released drug only upon enzymatic digestion, and demonstrated preferential adhesion to inflamed epithelial surfaces in vitro and in two mouse colitis models in vivo. Dex-loaded IT-hydrogel enemas, but not free Dex enemas, administered every other day to mice with colitis resulted in a significant reduction in inflammation and were associated with lower Dex peak serum concentrations and, thus, less systemic drug exposure. Ex vivo analysis of colon tissue samples from patients with ulcerative colitis demonstrated that IT-hydrogel microfibers adhered preferentially to mucosa from inflamed lesions compared with histologically normal sites. The IT-hydrogel drug delivery platform represents a promising approach for targeted enema-based therapies in patients with colonic IBD.

    6. Crowd sourcing a new paradigm for interactome driven drug target identification in Mycobacterium tuberculosis.

      Directory of Open Access Journals (Sweden)

      Rohit Vashisht

      Full Text Available A decade since the availability of Mycobacterium tuberculosis (Mtb genome sequence, no promising drug has seen the light of the day. This not only indicates the challenges in discovering new drugs but also suggests a gap in our current understanding of Mtb biology. We attempt to bridge this gap by carrying out extensive re-annotation and constructing a systems level protein interaction map of Mtb with an objective of finding novel drug target candidates. Towards this, we synergized crowd sourcing and social networking methods through an initiative 'Connect to Decode' (C2D to generate the first and largest manually curated interactome of Mtb termed 'interactome pathway' (IPW, encompassing a total of 1434 proteins connected through 2575 functional relationships. Interactions leading to gene regulation, signal transduction, metabolism, structural complex formation have been catalogued. In the process, we have functionally annotated 87% of the Mtb genome in context of gene products. We further combine IPW with STRING based network to report central proteins, which may be assessed as potential drug targets for development of drugs with least possible side effects. The fact that five of the 17 predicted drug targets are already experimentally validated either genetically or biochemically lends credence to our unique approach.

    7. A novel targeted system to deliver chemotherapeutic drugs to EphA2-expressing cancer cells

      OpenAIRE

      Wang, Si; Placzek, William J.; Stebbins, John L.; Mitra, Sayantan; Noberini, Roberta; Koolpe, Mitchell; Zhang, Ziming; Dahl, Russell; Pasquale, Elena B.; Pellecchia, Maurizio

      2012-01-01

      The efficacy of anti-cancer drugs is often limited by their systemic toxicities and adverse side effects. We report that the EphA2 receptor is over-expressed preferentially in several human cancer cell lines compared to normal tissues and that an EphA2 targeting peptide (YSAYPDSVPMMS) can be effective in delivering anti-cancer agents to such tumors. Hence, we report on the synthesis and characterizations of a novel EphA2-targeting agent conjugated with the chemotherapeutic drug paclitaxel. We...

    8. The Validation of Nematode-Specific Acetylcholine-Gated Chloride Channels as Potential Anthelmintic Drug Targets

      Science.gov (United States)

      Wever, Claudia M.; Farrington, Danielle; Dent, Joseph A.

      2015-01-01

      New compounds are needed to treat parasitic nematode infections in humans, livestock and plants. Small molecule anthelmintics are the primary means of nematode parasite control in animals; however, widespread resistance to the currently available drug classes means control will be impossible without the introduction of new compounds. Adverse environmental effects associated with nematocides used to control plant parasitic species are also motivating the search for safer, more effective compounds. Discovery of new anthelmintic drugs in particular has been a serious challenge due to the difficulty of obtaining and culturing target parasites for high-throughput screens and the lack of functional genomic techniques to validate potential drug targets in these pathogens. We present here a novel strategy for target validation that employs the free-living nematode Caenorhabditis elegans to demonstrate the value of new ligand-gated ion channels as targets for anthelmintic discovery. Many successful anthelmintics, including ivermectin, levamisole and monepantel, are agonists of pentameric ligand-gated ion channels, suggesting that the unexploited pentameric ion channels encoded in parasite genomes may be suitable drug targets. We validated five members of the nematode-specific family of acetylcholine-gated chloride channels as targets of agonists with anthelmintic properties by ectopically expressing an ivermectin-gated chloride channel, AVR-15, in tissues that endogenously express the acetylcholine-gated chloride channels and using the effects of ivermectin to predict the effects of an acetylcholine-gated chloride channel agonist. In principle, our strategy can be applied to validate any ion channel as a putative anti-parasitic drug target. PMID:26393923

    9. Surface Modified Multifunctional and Stimuli Responsive Nanoparticles for Drug Targeting: Current Status and Uses.

      Science.gov (United States)

      Siafaka, Panoraia I; Üstündağ Okur, Neslihan; Karavas, Evangelos; Bikiaris, Dimitrios N

      2016-01-01

      Nanocarriers, due to their unique features, are of increased interest among researchers working with pharmaceutical formulations. Polymeric nanoparticles and nanocapsules, involving non-toxic biodegradable polymers, liposomes, solid lipid nanoparticles, and inorganic-organic nanomaterials, are among the most used carriers for drugs for a broad spectrum of targeted diseases. In fact, oral, injectable, transdermal-dermal and ocular formulations mainly consist of the aforementioned nanomaterials demonstrating promising characteristics such as long circulation, specific targeting, high drug loading capacity, enhanced intracellular penetration, and so on. Over the last decade, huge advances in the development of novel, safer and less toxic nanocarriers with amended properties have been made. In addition, multifunctional nanocarriers combining chemical substances, vitamins and peptides via coupling chemistry, inorganic particles coated by biocompatible materials seem to play a key role considering that functionalization can enhance characteristics such as biocompatibility, targetability, environmental friendliness, and intracellular penetration while also have limited side effects. This review aims to summarize the "state of the art" of drug delivery carriers in nanosize, paying attention to their surface functionalization with ligands and other small or polymeric compounds so as to upgrade active and passive targeting, different release patterns as well as cell targeting and stimuli responsibility. Lastly, future aspects and potential uses of nanoparticulated drug systems are outlined. PMID:27589733

    10. Methodologies and Application of New Target Identification, Drug Action Mechanism Investigation and New Molecular Entity Discovery

      Institute of Scientific and Technical Information of China (English)

      2011-01-01

      @@ The group, headed by Prof.JIANG Hualiang with the CAS Shanghai Institute of Materia Medica, has been centering on the basic research of pharmaceutical science, including identifying new targets, studying new drug action mechanisms and discovering new drug candidates.On the basis of new methodology development, an effective multi-disciplinary research platform for drug research and discovery has been established through the integration of different disciplines of computational chemistry, organic synthesis, molecular and cellular biology.A bunch of creative results have been achieved in these areas.

    11. DEVELOPMENT AND EVALUATION OF ENZYMATICALY TRIGGERED MULTIPARTICULATE COLON TARGETED DRUG DELIVERY SYSTEM

      Directory of Open Access Journals (Sweden)

      Mohapatra Santosh K

      2011-02-01

      Full Text Available The most critical challenge in oral colon specific drug delivery approach is to preserve the formulation during its passage through the stomach and about first six meters of the small intestine. Microbial enzyme-triggering mechanisms seem to be promising to provide more reliable colonic delivery .The objective of the present study was to develop biodegradable colon targeted multiparticulate system by using guar gum. In this study drug (Budesonide loaded pellets were coated with aqueous guar gum solution and subjected to In-vitro drug release studies simulating GIT with and without enzyme as well as coating properties were evaluated by SEM. In-vitro release studies indicates that drug release after 4.5 h lag time in presence of enzyme and lag time increase in absence of enzyme which indicated the enzyme triggered system for colonic release. This Multiparticulate system can be effectively used for colonic drug delivery for effective treatment of colonic diseases.

    12. NASAL ROUTE: A NOVELISTIC APPROACH FOR TARGETED DRUG DELIVERY TO CNS

      Directory of Open Access Journals (Sweden)

      Choudhary Rakhi

      2013-03-01

      Full Text Available Drug delivery through nasal route has attracted the interest of scientific community as it has been potentially explored as an alternative route for the administration of vaccines and biomolecules such as proteins, peptides and non-peptide drugs that are susceptible to enzymatic or acidic degradation and first-pass hepatic metabolism. The nasal mucosa is one of the most permeable and highly vascularised sites for drug administration ensuring rapid absorption and onset of therapeutic action. Intranasal administration is a non-invasive route for drug delivery, which is widely used for the local treatment of rhinitis or nasal polyposis. Since drugs can be absorbed into the systemic circulation through the nasal mucosa, this route may also be used in a range of acute or chronic conditions requiring considerable systemic exposure. In addition it minimizes the lag time associated with oral drug delivery and offers non-invasiveness, self medication, patient comfort and patient compliance which are hurdled in intravenous drug therapy. The objective of this review is to provide an anatomical, histological and physiological overview of nose, absorption enhancers, barriers related to nasal drug delivery, physicochemical, biological and formulation related factors affecting nasal drug delivery system and its advantages. It also highlights research approaches on brain targeting through nasal cavity.

    13. Doxorubicin loaded PVA coated iron oxide nanoparticles for targeted drug delivery

      International Nuclear Information System (INIS)

      Magnetic drug targeting is a drug delivery system that can be used in locoregional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by coprecipitation of iron oxide followed by coating with polyvinyl alcohol (PVA). Characterization was carried out using X-ray diffraction, TEM, TGA, FTIR and VSM techniques. The magnetic core of the carriers was magnetite (Fe3O4), with average size of 10 nm. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. The amount of PVA bound to the iron oxide nanoparticles were estimated by thermogravimetric analysis (TGA) and the attachment of PVA to the iron oxide nanoparticles was confirmed by FTIR analysis. Doxorubicin (DOX) drug loading and release profiles of PVA coated iron oxide nanoparticles showed that up to 45% of adsorbed drug was released in 80 h, the drug release followed the Fickian diffusion-controlled process. The binding of DOX to the PVA was confirmed by FTIR analysis. The present findings show that DOX loaded PVA coated iron oxide nanoparticles are promising for magnetically targeted drug delivery.

    14. Gene Ontology and KEGG Pathway Enrichment Analysis of a Drug Target-Based Classification System.

      Directory of Open Access Journals (Sweden)

      Lei Chen

      Full Text Available Drug-target interaction (DTI is a key aspect in pharmaceutical research. With the ever-increasing new drug data resources, computational approaches have emerged as powerful and labor-saving tools in predicting new DTIs. However, so far, most of these predictions have been based on structural similarities rather than biological relevance. In this study, we proposed for the first time a "GO and KEGG enrichment score" method to represent a certain category of drug molecules by further classification and interpretation of the DTI database. A benchmark dataset consisting of 2,015 drugs that are assigned to nine categories ((1 G protein-coupled receptors, (2 cytokine receptors, (3 nuclear receptors, (4 ion channels, (5 transporters, (6 enzymes, (7 protein kinases, (8 cellular antigens and (9 pathogens was constructed by collecting data from KEGG. We analyzed each category and each drug for its contribution in GO terms and KEGG pathways using the popular feature selection "minimum redundancy maximum relevance (mRMR" method, and key GO terms and KEGG pathways were extracted. Our analysis revealed the top enriched GO terms and KEGG pathways of each drug category, which were highly enriched in the literature and clinical trials. Our results provide for the first time the biological relevance among drugs, targets and biological functions, which serves as a new basis for future DTI predictions.

    15. Layered Double Hydroxide Modified by PEGylated Hyaluronic Acid as a Hybrid Nanocarrier for Targeted Drug Delivery

      Institute of Scientific and Technical Information of China (English)

      董岸杰; 李雪; 王伟伟; 韩尚聪; 刘鉴锋; 刘金剑; 赵军强; 许舒欣; 邓联东

      2016-01-01

      In recent years, organic-inorganic hybrid nanocarriers are explored for effective drug delivery and pref-erable disease treatments. In this study, using 5-fluorouracil(5-FU)as electronegative model drug, a new type of organic-inorganic hybrid drug delivery system(LDH/HA-PEG/5-FU)was conceived and manufactured by the ad-sorption of PEGylated hyaluronic acid(HA-PEG)on the surface of layered double hydroxide(LDH, prepared via hydrothermal method)and the intercalation of 5-FU in the interlamination of LDH via ion exchange strategy. The drug loading amount of LDH/HA-PEG/5-FU achieved as high as 34.2%. LDH, LDH/5-FU and LDH/HA-PEG/5-FU were characterized by FT-IR, XRD, TGA, laser particle size analyzer and SEM. With the benefit of pH-degradable feature of LDH and enzyme-degradable feature of HA, LDH/HA-PEG/5-FU showed pH-degradable and enzyme-degradable capacity inin vitro drug release. Moreover, the drug carrier LDH/HA-PEG contained biocom-patible PEG and tumor-targeted HA, resulting in lower cytotoxicity and better endocytosis compared with LDHin vitro. It was suggested that the organic-inorganic hybrid drug delivery system, which was endowed with the proper-ties of controlled release, low toxicity and tumor-targeting delivery for ameliorative cancer therapy, was advisable and might be applied further to fulfill other treatments.

    16. Combating malaria with nanotechnology-based targeted and combinatorial drug delivery strategies.

      Science.gov (United States)

      Thakkar, Miloni; S, Brijesh

      2016-08-01

      Despite the advancement of science, infectious diseases such as malaria remain an ongoing challenge globally. The main reason this disease still remains a menace in many countries around the world is the development of resistance to many of the currently available anti-malarial drugs. While developing new drugs is rather expensive and the prospect of a potent vaccine is still evading our dream of a malaria-free world, one of the feasible options is to package the older drugs in newer ways. For this, nano-sized drug delivery vehicles have been used and are proving to be promising prospects in the way malaria will be treated in the future. Since, monotherapy has given way to combination therapy in malaria treatment, nanotechnology-based delivery carriers enable to encapsulate various drug moieties in the same package, thus avoiding the complications involved in conjugation chemistry to produce hybrid drug molecules. Further, we envisage that using targeted delivery approaches, we may be able to achieve a much better radical cure and curb the side effects associated with the existing drug molecules. Thus, this review will focus on some of the nanotechnology-based combination and targeted therapies and will discuss the possibilities of better therapies that may be developed in the future. PMID:27067712

    17. Doxorubicin loaded PVA coated iron oxide nanoparticles for targeted drug delivery

      Energy Technology Data Exchange (ETDEWEB)

      Kayal, S. [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Ramanujan, R.V., E-mail: ramanujan@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

      2010-04-06

      Magnetic drug targeting is a drug delivery system that can be used in locoregional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by coprecipitation of iron oxide followed by coating with polyvinyl alcohol (PVA). Characterization was carried out using X-ray diffraction, TEM, TGA, FTIR and VSM techniques. The magnetic core of the carriers was magnetite (Fe{sub 3}O{sub 4}), with average size of 10 nm. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. The amount of PVA bound to the iron oxide nanoparticles were estimated by thermogravimetric analysis (TGA) and the attachment of PVA to the iron oxide nanoparticles was confirmed by FTIR analysis. Doxorubicin (DOX) drug loading and release profiles of PVA coated iron oxide nanoparticles showed that up to 45% of adsorbed drug was released in 80 h, the drug release followed the Fickian diffusion-controlled process. The binding of DOX to the PVA was confirmed by FTIR analysis. The present findings show that DOX loaded PVA coated iron oxide nanoparticles are promising for magnetically targeted drug delivery.

    18. Exploring New Drug Targets through the Identification of Target Molecules of Bioactive Natural Products.

      Science.gov (United States)

      Arai, Masayoshi

      2016-01-01

      With the development of cell biology and microbiology, it has become easy to culture many types of animal cells and microbes, and they are frequently used for phenotypic screening to explore medicinal seeds. On the other hand, it is recognized that cells and pathogenic microbes present in pathologic sites and infected regions of the human body display unique properties different from those under general culture conditions. We isolated several bioactive compounds from marine medicinal resources using constructed bioassay-guided separation focusing on the unique changes in the characteristics of cells and pathogenic microbes (Mycobacterium spp.) in the human body under disease conditions. In addition, we also carried out identification studies of target molecules of the bioactive compounds by methods utilizing the gene expression profile, transformants of cells or microbes, synthetic probe molecules of the isolated compounds, etc., since bioactive compounds isolated from the phenotypic screening system often target new molecules. This review presents our phenotypic screening systems, isolation of bioactive compounds from marine medicinal resources, and target identification of bioactive compounds. PMID:27040348

    19. Targeted Skipping of Human Dystrophin Exons in Transgenic Mouse Model Systemically for Antisense Drug Development

      OpenAIRE

      Bo Wu; Ehsan Benrashid; Peijuan Lu; Caryn Cloer; Allen Zillmer; Mona Shaban; Qi Long Lu

      2011-01-01

      Antisense therapy has recently been demonstrated with great potential for targeted exon skipping and restoration of dystrophin production in cultured muscle cells and in muscles of Duchenne Muscular Dystrophy (DMD) patients. Therapeutic values of exon skipping critically depend on efficacy of the drugs, antisense oligomers (AOs). However, no animal model has been established to test AO targeting human dystrophin exon in vivo systemically. In this study, we applied Vivo-Morpholino to the hDMD/...

    20. Phytochemical-mediated Protein Expression Profiling and the Potential Applications in Therapeutic Drug Target Identifications.

      Science.gov (United States)

      Wong, Fai-Chu; Tan, Siok-Thing; Chai, Tsun-Thai

      2016-07-29

      Many phytochemicals derived from edible medicinal plants have been investigated intensively for their various bioactivities. However, the detailed mechanism and their corresponding molecular targets frequently remain elusive. In this review, we present a summary of the research works done on phytochemical-mediated molecular targets, identified via proteomic approach. Concurrently, we also highlighted some pharmaceutical drugs which could be traced back to their origins in phytochemicals. For ease of presentation, these identified protein targets were categorized into two important healthcare-related fields, namely anti-bacterial and anti-cancer research. Through this review, we hope to highlight the usefulness of comparative proteomic as a powerful tool in phytochemical-mediated protein target identifications. Likewise, we wish to inspire further investigations on some of these protein targets identified over the last few years. With contributions from all researchers, the accumulative efforts could eventually lead to the discovery of some target-specific, low-toxicity therapeutic agents. PMID:26193174

    1. Depth-targeted transvascular drug delivery by using annular-shaped photomechanical waves

      Science.gov (United States)

      Akiyama, Takuya; Sato, Shunichi; Ashida, Hiroshi; Terakawa, Mitsuhiro

      2011-02-01

      Laser-based drug delivery is attractive for the targeting capability due to high spatial controllability of laser energy. Recently, we found that photomechanical waves (PMWs) can transiently increase the permeability of blood vessels in skin, muscle and brain of rats. In this study, we examined the use of annular-shaped PMWs to increase pressure at target depths due to superposition effect of pressure waves. This can increase the permeability of blood vessels located in the specific depth regions, enabling depth-targeted transvascular drug delivery. Annular PMWs were produced by irradiating a laser-absorbing material with annular-shaped pulsed laser beams that were produced by using an axicon lens. We first examined propagation and pressure characteristics of annular PMWs in tissue phantoms and confirmed an increased pressure at a target depth, which can be controlled by changing laser parameters. We injected Evans blue (EB) into a rat tail vein, and annular PMWs (inner diameter, 3 mm; outer diameter, 5 mm) were applied from the myofascial surface of the anterior tibialis muscle. After perfusion fixation, we observed fluorescence originating from EB in the tissue. We observed intense fluorescence at a target depth region of around 5 mm. These results demonstrate the capability of annular PMWs for depth-targeted transvascular drug delivery.

    2. Application of CellDesigner to the Selection of Anticancer Drug Targets: Test Case using P53

      OpenAIRE

      Isea, Raul; Hoebeke, Johan; Mayo, Rafael; Alvarez, Fernando; Holmes, David S.

      2013-01-01

      Cancer is a disease involving many genes, consequently it has been difficult to design anticancer drugs that are efficacious over a broad range of cancers. The robustness of cellular responses to gene knockout and the need to reduce undesirable side effects also contribute to the problem of effective anti-cancer drug design. To promote the successful selection of drug targets, each potential target should be subjected to a systems biology scrutiny to locate effective and specific targets whil...

    3. Identification of attractive drug targets in neglected-disease pathogens using an in silico approach.

      Directory of Open Access Journals (Sweden)

      Gregory J Crowther

      Full Text Available BACKGROUND: The increased sequencing of pathogen genomes and the subsequent availability of genome-scale functional datasets are expected to guide the experimental work necessary for target-based drug discovery. However, a major bottleneck in this has been the difficulty of capturing and integrating relevant information in an easily accessible format for identifying and prioritizing potential targets. The open-access resource TDRtargets.org facilitates drug target prioritization for major tropical disease pathogens such as the mycobacteria Mycobacterium leprae and Mycobacterium tuberculosis; the kinetoplastid protozoans Leishmania major, Trypanosoma brucei, and Trypanosoma cruzi; the apicomplexan protozoans Plasmodium falciparum, Plasmodium vivax, and Toxoplasma gondii; and the helminths Brugia malayi and Schistosoma mansoni. METHODOLOGY/PRINCIPAL FINDINGS: Here we present strategies to prioritize pathogen proteins based on whether their properties meet criteria considered desirable in a drug target. These criteria are based upon both sequence-derived information (e.g., molecular mass and functional data on expression, essentiality, phenotypes, metabolic pathways, assayability, and druggability. This approach also highlights the fact that data for many relevant criteria are lacking in less-studied pathogens (e.g., helminths, and we demonstrate how this can be partially overcome by mapping data from homologous genes in well-studied organisms. We also show how individual users can easily upload external datasets and integrate them with existing data in TDRtargets.org to generate highly customized ranked lists of potential targets. CONCLUSIONS/SIGNIFICANCE: Using the datasets and the tools available in TDRtargets.org, we have generated illustrative lists of potential drug targets in seven tropical disease pathogens. While these lists are broadly consistent with the research community's current interest in certain specific proteins, and suggest

    4. Magnetic Nanoparticles as Intraocular Drug Delivery System to Target Retinal Pigmented Epithelium (RPE)

      Science.gov (United States)

      Giannaccini, Martina; Giannini, Marianna; Calatayud, M. Pilar; Goya, Gerardo F.; Cuschieri, Alfred; Dente, Luciana; Raffa, Vittoria

      2014-01-01

      One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs) as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE) layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work. Moreover, through similar experiments in zebrafish, we demonstrated that the targeting of RPE by the nanoparticles is not specific for the Xenopus species. PMID:24451140

    5. Predicting drug-target interaction networks based on functional groups and biological features.

      Directory of Open Access Journals (Sweden)

      Zhisong He

      Full Text Available BACKGROUND: Study of drug-target interaction networks is an important topic for drug development. It is both time-consuming and costly to determine compound-protein interactions or potential drug-target interactions by experiments alone. As a complement, the in silico prediction methods can provide us with very useful information in a timely manner. METHODS/PRINCIPAL FINDINGS: To realize this, drug compounds are encoded with functional groups and proteins encoded by biological features including biochemical and physicochemical properties. The optimal feature selection procedures are adopted by means of the mRMR (Maximum Relevance Minimum Redundancy method. Instead of classifying the proteins as a whole family, target proteins are divided into four groups: enzymes, ion channels, G-protein- coupled receptors and nuclear receptors. Thus, four independent predictors are established using the Nearest Neighbor algorithm as their operation engine, with each to predict the interactions between drugs and one of the four protein groups. As a result, the overall success rates by the jackknife cross-validation tests achieved with the four predictors are 85.48%, 80.78%, 78.49%, and 85.66%, respectively. CONCLUSION/SIGNIFICANCE: Our results indicate that the network prediction system thus established is quite promising and encouraging.

    6. Pluronic F127 nanomicelles engineered with nuclear localized functionality for targeted drug delivery.

      Science.gov (United States)

      Li, Yong-Yong; Li, Lan; Dong, Hai-Qing; Cai, Xiao-Jun; Ren, Tian-Bin

      2013-07-01

      PKKKRKV (Pro-Lys-Lys-Lys-Arg-Lys-Val, PV7), a seven amino acid peptide, has emerged as one of the primary nuclear localization signals that can be targeted into cell nucleus via the nuclear import machinery. Taking advantage of chemical diversity and biological activities of this short peptide sequence, in this study, Pluronic F127 nanomicelles engineered with nuclear localized functionality were successfully developed for intracellular drug delivery. These nanomicelles with the size ~100 nm were self-assembled from F127 polymer that was flanked with two PV7 sequences at its both terminal ends. Hydrophobic anticancer drug doxorubicin (DOX) with inherent fluorescence was chosen as the model drug, which was found to be efficiently encapsulated into nanomicelles with the encapsulation efficiency at 72.68%. In comparison with the non-functionalized namomicelles, the microscopic observation reveals that PV7 functionalized nanomicelles display a higher cellular uptake, especially into the nucleus of HepG2 cells, due to the nuclear localization signal effects. Both cytotoxicity and apoptosis studies show that the DOX-loaded nanomicelles were more potent than drug nanomicelles without nuclear targeting functionality. It was thus concluded that PV7 functionalized nanomicelles could be a potentially alternative vehicle for nuclear targeting drug delivery.

    7. Magnetic Nanoparticles as Intraocular Drug Delivery System to Target Retinal Pigmented Epithelium (RPE

      Directory of Open Access Journals (Sweden)

      Martina Giannaccini

      2014-01-01

      Full Text Available One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work. Moreover, through similar experiments in zebrafish, we demonstrated that the targeting of RPE by the nanoparticles is not specific for the Xenopus species.

    8. Proteins with complex architecture as potential targets for drug design: a case study of Mycobacterium tuberculosis.

      Directory of Open Access Journals (Sweden)

      Bálint Mészáros

      2011-07-01

      Full Text Available Lengthy co-evolution of Homo sapiens and Mycobacterium tuberculosis, the main causative agent of tuberculosis, resulted in a dramatically successful pathogen species that presents considerable challenge for modern medicine. The continuous and ever increasing appearance of multi-drug resistant mycobacteria necessitates the identification of novel drug targets and drugs with new mechanisms of action. However, further insights are needed to establish automated protocols for target selection based on the available complete genome sequences. In the present study, we perform complete proteome level comparisons between M. tuberculosis, mycobacteria, other prokaryotes and available eukaryotes based on protein domains, local sequence similarities and protein disorder. We show that the enrichment of certain domains in the genome can indicate an important function specific to M. tuberculosis. We identified two families, termed pkn and PE/PPE that stand out in this respect. The common property of these two protein families is a complex domain organization that combines species-specific regions, commonly occurring domains and disordered segments. Besides highlighting promising novel drug target candidates in M. tuberculosis, the presented analysis can also be viewed as a general protocol to identify proteins involved in species-specific functions in a given organism. We conclude that target selection protocols should be extended to include proteins with complex domain architectures instead of focusing on sequentially unique and essential proteins only.

    9. Degradable Magnetic Composites for Minimally Invasive Interventions: Device Fabrication, Targeted Drug Delivery, and Cytotoxicity Tests.

      Science.gov (United States)

      Peters, Christian; Hoop, Marcus; Pané, Salvador; Nelson, Bradley J; Hierold, Christofer

      2016-01-20

      Superparamagnetic nanoparticles and a functional, degradable polymer matrix based on poly(ethylene glycol) are combined to enable fully degradable magnetic microdevices for minimally invasive biomedical applications. A bioinspired helical microrobot platform mimicking Escherichia coli bacteria is fabricated and actuated using weak rotating magnetic fields. Locomotion based on corkscrew propulsion, targeted drug delivery, and low-degradation-product cytotoxicity are demonstrated. PMID:26603856

    10. Rho-kinase as a drug target for the treatment of airway hyperresponsiveness in asthma

      NARCIS (Netherlands)

      Gosens, R; Schaafsma, D; Nelemans, SA; Halayko, AJ

      2006-01-01

      In asthma, inflammatory and structural cells contribute to increased bronchoconstriction acutely and more chronically to airway remodelling. Current asthma therapy doesn't inhibit these features satisfactorily. This review discusses Rho-kinase as a potential drug target, since increasing evidence su

    11. Mechanisms of acquired resistance to androgen receptor targeting drugs in castration resistant prostate cancer

      OpenAIRE

      Chism, David D.; De Silva, Dinuka; Whang, Young E.

      2014-01-01

      After initial response to androgen receptor targeting drugs abiraterone or enzalutamide, most patients develop progressive disease and therefore, castration resistant prostate cancer (CRPC) remains a terminal disease. Multiple mechanisms underlying acquired resistance have been postulated. Intratumoral androgen synthesis may resume after abiraterone treatment. A point mutation in the ligand binding domain of androgen receptor may confer resistance to enzalutamide. Emergence of androgen recept...

    12. Rational Design of Targeted Next-Generation Carriers for Drug and Vaccine Delivery.

      Science.gov (United States)

      Narasimhan, Balaji; Goodman, Jonathan T; Vela Ramirez, Julia E

      2016-07-11

      Pattern recognition receptors on innate immune cells play an important role in guiding how cells interact with the rest of the organism and in determining the direction of the downstream immune response. Recent advances have elucidated the structure and function of these receptors, providing new opportunities for developing targeted drugs and vaccines to treat infections, cancers, and neurological disorders. C-type lectin receptors, Toll-like receptors, and folate receptors have attracted interest for their ability to endocytose their ligands or initiate signaling pathways that influence the immune response. Several novel technologies are being developed to engage these receptors, including recombinant antibodies, adoptive immunotherapy, and chemically modified antigens and drug delivery vehicles. These active targeting technologies will help address current challenges facing drug and vaccine delivery and lead to new tools to treat human diseases.

    13. Challenges in the design of clinically useful brain-targeted drug nanocarriers.

      Science.gov (United States)

      Costantino, L; Boraschi, D; Eaton, M

      2014-01-01

      Nowadays, the delivery of drugs by means of intravenously administered nanosized drug carriers - polymerdrug conjugates, liposomes and micelles, is technically possible. These delivery systems are mainly designed for tumour therapy, and accumulate passively into tumours by means of the well known EPR effect. Targeted nanocarriers, that additionally contain ligands for receptors expressed on cell surfaces, are also widely studied but products of this kind are not marketed, and only a few are in clinical trial. Polymeric nanoparticles (Np) able to deliver drugs to the CNS were pioneered in 1995; a number of papers have been published dealing with brain-targeted drug delivery using polymeric Np able to cross the BBB, mainly for the treatment of brain tumours. At present, however, the translation potential of these Np seems to have been exceeded by targeted liposomes, a platform based on a proven technology. This drug delivery system entered clinical trials soon after its discovery, while the challenges in formulation, characterization and manufacturing of brain-targeted polymeric Np and the cost/benefit ratio could be the factors that have prevented their development. A key issue is that it is virtually impossible to define the in vivo fate of polymers, especially in the brain, which is a regulatory requirement; perhaps this is why no progress has been made. The most advanced Np for brain tumours treatment will be compared here with the published data available for those in clinical trial for tumours outside the CNS, to highlight the knowledge gaps that still penalise these delivery systems. At present, new approaches for brain tumours are emerging, such as lipid Np or the use of monoclonal antibody (mAb)-drug conjugates, which avoid polymers. The success or failure in the approval of the polymeric Np currently in clinical trials will certainly affect the field. At present, the chances of their approval appear to be very low.

    14. Genetic validation of aminoacyl-tRNA synthetases as drug targets in Trypanosoma brucei.

      Science.gov (United States)

      Kalidas, Savitha; Cestari, Igor; Monnerat, Severine; Li, Qiong; Regmi, Sandesh; Hasle, Nicholas; Labaied, Mehdi; Parsons, Marilyn; Stuart, Kenneth; Phillips, Margaret A

      2014-04-01

      Human African trypanosomiasis (HAT) is an important public health threat in sub-Saharan Africa. Current drugs are unsatisfactory, and new drugs are being sought. Few validated enzyme targets are available to support drug discovery efforts, so our goal was to obtain essentiality data on genes with proven utility as drug targets. Aminoacyl-tRNA synthetases (aaRSs) are known drug targets for bacterial and fungal pathogens and are required for protein synthesis. Here we survey the essentiality of eight Trypanosoma brucei aaRSs by RNA interference (RNAi) gene expression knockdown, covering an enzyme from each major aaRS class: valyl-tRNA synthetase (ValRS) (class Ia), tryptophanyl-tRNA synthetase (TrpRS-1) (class Ib), arginyl-tRNA synthetase (ArgRS) (class Ic), glutamyl-tRNA synthetase (GluRS) (class 1c), threonyl-tRNA synthetase (ThrRS) (class IIa), asparaginyl-tRNA synthetase (AsnRS) (class IIb), and phenylalanyl-tRNA synthetase (α and β) (PheRS) (class IIc). Knockdown of mRNA encoding these enzymes in T. brucei mammalian stage parasites showed that all were essential for parasite growth and survival in vitro. The reduced expression resulted in growth, morphological, cell cycle, and DNA content abnormalities. ThrRS was characterized in greater detail, showing that the purified recombinant enzyme displayed ThrRS activity and that the protein localized to both the cytosol and mitochondrion. Borrelidin, a known inhibitor of ThrRS, was an inhibitor of T. brucei ThrRS and showed antitrypanosomal activity. The data show that aaRSs are essential for T. brucei survival and are likely to be excellent targets for drug discovery efforts. PMID:24562907

    15. The Research and Applications of Quantum Dots as Nano-Carriers for Targeted Drug Delivery and Cancer Therapy

      Science.gov (United States)

      Zhao, Mei-Xia; Zhu, Bing-Jie

      2016-04-01

      Quantum dots (QDs), nano-carriers for drugs, can help realize the targeting of drugs, and improve the bioavailability of drugs in biological fields. And, a QD nano-carrier system for drugs has the potential to realize early detection, monitoring, and localized treatments of specific disease sites. In addition, QD nano-carrier systems for drugs can improve stability of drugs, lengthen circulation time in vivo, enhance targeted absorption, and improve the distribution and metabolism process of drugs in organization. So, the development of QD nano-carriers for drugs has become a hotspot in the fields of nano-drug research in recent years. In this paper, we review the advantages and applications of the QD nano-carriers for drugs in biological fields.

    16. The Research and Applications of Quantum Dots as Nano-Carriers for Targeted Drug Delivery and Cancer Therapy.

      Science.gov (United States)

      Zhao, Mei-Xia; Zhu, Bing-Jie

      2016-12-01

      Quantum dots (QDs), nano-carriers for drugs, can help realize the targeting of drugs, and improve the bioavailability of drugs in biological fields. And, a QD nano-carrier system for drugs has the potential to realize early detection, monitoring, and localized treatments of specific disease sites. In addition, QD nano-carrier systems for drugs can improve stability of drugs, lengthen circulation time in vivo, enhance targeted absorption, and improve the distribution and metabolism process of drugs in organization. So, the development of QD nano-carriers for drugs has become a hotspot in the fields of nano-drug research in recent years. In this paper, we review the advantages and applications of the QD nano-carriers for drugs in biological fields. PMID:27090658

    17. Smuggling Drugs into the Brain: An Overview of Ligands Targeting Transcytosis for Drug Delivery across the Blood–Brain Barrier

      Directory of Open Access Journals (Sweden)

      Julia V. Georgieva

      2014-11-01

      Full Text Available The blood–brain barrier acts as a physical barrier that prevents free entry of blood-derived substances, including those intended for therapeutic applications. The development of molecular Trojan horses is a promising drug targeting technology that allows for non-invasive delivery of therapeutics into the brain. This concept relies on the application of natural or genetically engineered proteins or small peptides, capable of specifically ferrying a drug-payload that is either directly coupled or encapsulated in an appropriate nanocarrier, across the blood–brain barrier via receptor-mediated transcytosis. Specifically, in this process the nanocarrier–drug system (“Trojan horse complex” is transported transcellularly across the brain endothelium, from the blood to the brain interface, essentially trailed by a native receptor. Naturally, only certain properties would favor a receptor to serve as a transporter for nanocarriers, coated with appropriate ligands. Here we briefly discuss brain microvascular endothelial receptors that have been explored until now, highlighting molecular features that govern the efficiency of nanocarrier-mediated drug delivery into the brain.

    18. Functional expression of parasite drug targets and their human orthologs in yeast.

      Directory of Open Access Journals (Sweden)

      Elizabeth Bilsland

      2011-10-01

      Full Text Available BACKGROUND: The exacting nutritional requirements and complicated life cycles of parasites mean that they are not always amenable to high-throughput drug screening using automated procedures. Therefore, we have engineered the yeast Saccharomyces cerevisiae to act as a surrogate for expressing anti-parasitic targets from a range of biomedically important pathogens, to facilitate the rapid identification of new therapeutic agents. METHODOLOGY/PRINCIPAL FINDINGS: Using pyrimethamine/dihydrofolate reductase (DHFR as a model parasite drug/drug target system, we explore the potential of engineered yeast strains (expressing DHFR enzymes from Plasmodium falciparum, P. vivax, Homo sapiens, Schistosoma mansoni, Leishmania major, Trypanosoma brucei and T. cruzi to exhibit appropriate differential sensitivity to pyrimethamine. Here, we demonstrate that yeast strains (lacking the major drug efflux pump, Pdr5p expressing yeast ((ScDFR1, human ((HsDHFR, Schistosoma ((SmDHFR, and Trypanosoma ((TbDHFR and (TcDHFR DHFRs are insensitive to pyrimethamine treatment, whereas yeast strains producing Plasmodium ((PfDHFR and (PvDHFR DHFRs are hypersensitive. Reassuringly, yeast strains expressing field-verified, drug-resistant mutants of P. falciparum DHFR ((Pfdhfr(51I,59R,108N are completely insensitive to pyrimethamine, further validating our approach to drug screening. We further show the versatility of the approach by replacing yeast essential genes with other potential drug targets, namely phosphoglycerate kinases (PGKs and N-myristoyl transferases (NMTs. CONCLUSIONS/SIGNIFICANCE: We have generated a number of yeast strains that can be successfully harnessed for the rapid and selective identification of urgently needed anti-parasitic agents.

    19. Candidate Targets for New Anti-Virulence Drugs: Selected Cases of Bacterial Adhesion and Biofilm Formation

      DEFF Research Database (Denmark)

      Klemm, Per; Hancock, Viktoria; Kvist, Malin;

      2007-01-01

      formation are highly attractive targets for new drugs. Specific adhesion provides bacteria with target selection and prevents removal by hydrodynamic flow forces. Bacterial adhesion is of paramount importance for bacterial pathogenesis. Adhesion is also the first step in biofilm formation. Biofilm formation...... is particularly problematic in medical contexts because biofilm-associated bacteria are particularly hard to eradicate. Several promising candidate drugs that target bacterial adhesion and biofilm formation are being developed. Some of these might be valuable weapons for fighting infectious diseases in the future......Management of bacterial infections is becoming increasingly difficult due to the rising frequency of strains that are resistant to many current antibiotics. New types of antibiotics are, therefore, urgently needed. Virulence factors or virulence-associated phenotypes such as adhesins and biofilm...

    20. Identification of the Schistosoma mansoni Molecular Target for the Antimalarial Drug Artemether

      KAUST Repository

      Lepore, Rosalba

      2011-11-28

      Plasmodium falciparum and Schistosoma mansonii are the parasites responsible for most of the malaria and schistosomiasis cases in the world. Notwithstanding their many differences, the two agents have striking similarities in that they both are blood feeders and are targets of an overlapping set of drugs, including the well-known artemether molecule. Here we explore the possibility of using the known information about the mode of action of artemether in Plasmodium to identify the molecular target of the drug in Schistosoma and provide evidence that artemether binds to SmSERCA, a putative Ca2+-ATPase of Schistosoma. We also predict the putative binding mode of the molecule for both its Plasmodium and Schistosoma targets. Our analysis of the mode of binding of artemether to Ca2+-ATPases also provides an explanation for the apparent paradox that, although the molecule has no side effect in humans, it has been shown to possess antitumoral activity. © 2011 American Chemical Society.

    1. Targeted Shiga toxin-drug conjugates prepared via Cu-free click chemistry.

      Science.gov (United States)

      Kostova, Vesela; Dransart, Estelle; Azoulay, Michel; Brulle, Laura; Bai, Siau-Kun; Florent, Jean-Claude; Johannes, Ludger; Schmidt, Frédéric

      2015-11-15

      The main drawback of the anticancer chemotherapy consists in the lack of drug selectivity causing severe side effects. The targeted drug delivery appears to be a very promising strategy for controlling the biodistribution of the cytotoxic agent only on malignant tissues by linking it to tumor-targeting moiety. Here we exploit the natural characteristics of Shiga toxin B sub-unit (STxB) as targeting carrier on Gb3-positive cancer cells. Two cytotoxic conjugates STxB-doxorubicin (STxB-Doxo) and STxB-monomethyl auristatin F (STxB-MMAF) were synthesised using copper-free 'click' chemistry. Both conjugates were obtained in very high yield and demonstrated strong tumor inhibition activity in a nanomolar range on Gb3-positive cells.

    2. Using C. elegans to screen for targets of ethanol and behavior-altering drugs

      Directory of Open Access Journals (Sweden)

      Davies Andrew G.

      2004-01-01

      Full Text Available Caenorhabditis elegans is an attractive model system for determining the targets of neuroactive compounds. Genetic screens in C. elegans provide a relatively unbiased approach to the identification of genes that are essential for behavioral effects of drugs and neuroactive compounds such as alcohol. Much work in vertebrate systems has identified multiple potential targets of ethanol but which, if any, of those candidates are responsible for the behavioral effects of alcohol is uncertain. Here we provide detailed methodology for a genetic screen for mutants of C. elegans that are resistant to the depressive effects of ethanol on locomotion and for the subsequent behavioral analysis of those mutants. The methods we describe should also be applicable for use in screening for mutants that are resistant or hypersensitive to many neuroactive compounds and for identifying the molecular targets or biochemical pathways mediating drug responses.

    3. FLOATING GASTRO-RETENTIVE DOSAGE FORMS - A NOVEL APPROACH FOR TARGETED AND CONTROLLED DRUG DELIVERY

      Directory of Open Access Journals (Sweden)

      Aleksandar Aleksovski

      2012-04-01

      Full Text Available Controlled (modified release dosage forms are one of the key concepts in drug delivery, leading to enhanced drug bioavailability and increased patient’s compliance. However conventional modified release dosage forms encounter one big disadvantage- lack of site-specific drug delivery. Scientists developed different kinds of targeted oral controlled release forms. One of these are gastro-retentive systems- systems which can remain in the stomach region for prolonged period of time and thereby release the active compound in controlled fashion. Floating dosage forms are the most promising approach of all gastro-retentive systems. They are capable to float over the gastric content in longer time intervals. This article makes a review on floating dosage forms in general, different approaches for achieving flotation, advantages and disadvantages of this drug delivery concept. For better understanding the topic,an emphasis is made also on the anatomical and physiological features of the stomach and on the factors affecting gastric retention.

    4. Non-polymeric nano-carriers in HIV/AIDS drug delivery and targeting.

      Science.gov (United States)

      Gupta, Umesh; Jain, Narendra K

      2010-03-18

      Development of an effective drug delivery approach for the treatment of HIV/AIDS is a global challenge. The conventional drug delivery approaches including Highly Active Anti Retroviral Therapy (HAART) have increased the life span of the HIV/AIDS patient. However, the eradication of HIV is still not possible with these approaches due to some limitations. Emergence of polymeric and non-polymeric nanotechnological approaches can be opportunistic in this direction. Polymeric carriers like, dendrimers and nanoparticles have been reported for the targeting of anti HIV drugs. The synthetic pathways as well polymeric framework create some hurdles in their successful formulation development as well as in the possible drug delivery approaches. In the present article, we have discussed the general physiological aspects of the infection along with the relevance of non-polymeric nanocarriers like liposomes, solid lipid nanoparticles (SLN), ethosomes, etc. in the treatment of this disastrous disease. PMID:19913579

    5. Utilizing Chemical Genomics to Identify Cytochrome b as a Novel Drug Target for Chagas Disease.

      Directory of Open Access Journals (Sweden)

      Shilpi Khare

      2015-07-01

      Full Text Available Unbiased phenotypic screens enable identification of small molecules that inhibit pathogen growth by unanticipated mechanisms. These small molecules can be used as starting points for drug discovery programs that target such mechanisms. A major challenge of the approach is the identification of the cellular targets. Here we report GNF7686, a small molecule inhibitor of Trypanosoma cruzi, the causative agent of Chagas disease, and identification of cytochrome b as its target. Following discovery of GNF7686 in a parasite growth inhibition high throughput screen, we were able to evolve a GNF7686-resistant culture of T. cruzi epimastigotes. Clones from this culture bore a mutation coding for a substitution of leucine by phenylalanine at amino acid position 197 in cytochrome b. Cytochrome b is a component of complex III (cytochrome bc1 in the mitochondrial electron transport chain and catalyzes the transfer of electrons from ubiquinol to cytochrome c by a mechanism that utilizes two distinct catalytic sites, QN and QP. The L197F mutation is located in the QN site and confers resistance to GNF7686 in both parasite cell growth and biochemical cytochrome b assays. Additionally, the mutant cytochrome b confers resistance to antimycin A, another QN site inhibitor, but not to strobilurin or myxothiazol, which target the QP site. GNF7686 represents a promising starting point for Chagas disease drug discovery as it potently inhibits growth of intracellular T. cruzi amastigotes with a half maximal effective concentration (EC50 of 0.15 µM, and is highly specific for T. cruzi cytochrome b. No effect on the mammalian respiratory chain or mammalian cell proliferation was observed with up to 25 µM of GNF7686. Our approach, which combines T. cruzi chemical genetics with biochemical target validation, can be broadly applied to the discovery of additional novel drug targets and drug leads for Chagas disease.

    6. HER2-mediated anticancer drug delivery: strategies to prepare targeting ligands highly specific for the receptor.

      Science.gov (United States)

      Calce, Enrica; Monfregola, Luca; Saviano, Michele; De Luca, Stefania

      2015-01-01

      HER2 receptor, for its involvement in tumorigenesis, has been largely studied as topic in cancer research. In particular, the employment of trastuzumab (Herceptin), a humanized anti-HER2 antibody, showed several clinical benefits in the therapy against the breast cancer. Moreover, for its accessible extracellular domain, this receptor is considered an ideal target to deliver anticancer drugs for the receptormediated anticancer therapy. By now, monoclonal antibody and its fragments, affibody, and some peptides have been employed as targeting agents in order to deliver various drugs to HER2 positive tumor cells. In particular, the ability to perform a fast and reliable screening of a large number of peptide molecules would make possible the selection of highly specific compounds to the receptor target. In this regard, the availability of preparing a simplified synthetic model which is a good mimetic of the receptor target and can be used in a reliable screening method of ligands would be of a strategic importance for the development of selective HER2-targeting peptide molecules. Herein, we illustrate the importance of HER2-targeted anticancer therapies. We also report on a synthetic and effective mimetic of the receptor, which revealed to be a useful tool for the selection of specific HER2 ligands. PMID:25994863

    7. Laser-induced disruption of systemically administered liposomes for targeted drug delivery

      Science.gov (United States)

      Mackanos, Mark A.; Larabi, Malika; Shinde, Rajesh; Simanovskii, Dmitrii M.; Guccione, Samira; Contag, Christopher H.

      2009-07-01

      Liposomal formulations of drugs have been shown to enhance drug efficacy by prolonging circulation time, increasing local concentration and reducing off-target effects. Controlled release from these formulations would increase their utility, and hyperthermia has been explored as a stimulus for targeted delivery of encapsulated drugs. Use of lasers as a thermal source could provide improved control over the release of the drug from the liposomes with minimal collateral tissue damage. Appropriate methods for assessing local release after systemic delivery would aid in testing and development of better formulations. We use in vivo bioluminescence imaging to investigate the spatiotemporal distribution of luciferin, used as a model small molecule, and demonstrate laser-induced release from liposomes in animal models after systemic delivery. These liposomes were tested for luciferin release between 37 and 45 °C in PBS and serum using bioluminescence measurements. In vivo studies were performed on transgenic reporter mice that express luciferase constitutively throughout the body, thus providing a noninvasive readout for controlled release following systemic delivery. An Nd:YLF laser was used (527 nm) to heat tissues and induce rupture of the intravenously delivered liposomes in target tissues. These data demonstrate laser-mediated control of small molecule delivery using thermally sensitive liposomal formulations.

    8. Targeting stem cell signaling pathways for drug discovery: advances in the Notch and Wnt pathways.

      Science.gov (United States)

      An, Songzhu Michael; Ding, Qiang; Zhang, Jie; Xie, JingYi; Li, LingSong

      2014-06-01

      Signaling pathways transduce extracellular stimuli into cells through molecular cascades to regulate cellular functions. In stem cells, a small number of pathways, notably those of TGF-β/BMP, Hedgehog, Notch, and Wnt, are responsible for the regulation of pluripotency and differentiation. During embryonic development, these pathways govern cell fate specifications as well as the formation of tissues and organs. In adulthood, their normal functions are important for tissue homeostasis and regeneration, whereas aberrations result in diseases, such as cancer and degenerative disorders. In complex biological systems, stem cell signaling pathways work in concert as a network and exhibit crosstalk, such as the negative crosstalk between Wnt and Notch. Over the past decade, genetic and genomic studies have identified a number of potential drug targets that are involved in stem cell signaling pathways. Indeed, discovery of new targets and drugs for these pathways has become one of the most active areas in both the research community and pharmaceutical industry. Remarkable progress has been made and several promising drug candidates have entered into clinical trials. This review focuses on recent advances in the discovery of novel drugs which target the Notch and Wnt pathways.

    9. Targeting AMPK Signaling Pathway to Overcome Drug Resistance for Cancer Therapy.

      Science.gov (United States)

      Wang, Zhiyu; Liu, Pengxi; Chen, Qianjun; Deng, Shigui; Liu, Xiaoyan; Situ, Honglin; Zhong, Shaowen; Hann, Swei; Lin, Yi

      2016-01-01

      Mulitdrug resistance (MDR) is one of critical factorslimiting the efficacy of cancer chemoor radiotherapy. Emerging evidence has indicated that MDR is a complex process regulated by multiple factors, among which stress response molecules are considered as central players. AMP-activated protein kinase (AMPK) is a major regulator balancing energy supply and ultimately protects cells from harmful stresses via coordinating multiple metabolic pathways Notably, AMPK activation was recently shown to mediate the metabolism reprogramming in drug resistant cancer cells including promoting Warburg effects and mitochondrial biogenesis. Furthermore, AMPK activity has also been shown to regulate the self-renewal ability of cancer stem cells that are often refractory to chemotherapy. In addition, AMPK phosphorylation was critical in mediating autophagy induction, a process demonstrated to be effective in chemosensitivity modulation via degrading cellular components to satisfy nutrients requirement under stressful condition. Meanwhile, drug discovery targeting AMPK has been developed to validate the pathological significance of AMPK in cancer prevention and treatment. Although conflicting evidence focusing on the AMPK modulation for cancer treatment is still remained, this might be attributed to differences in AMPK isotypes in specific tissues, off-targets effects, the degree and duration of drug administration and experimental setting of stress conditions. This review will focus on AMPK mediated resistance to cancer therapy and discuss its potential therapeutic implication and targeting drug development. PMID:25777274

    10. Multifunctional quantum dot-polypeptide hybrid nanogel for targeted imaging and drug delivery

      Science.gov (United States)

      Yang, Jie; Yao, Ming-Hao; Wen, Lang; Song, Ji-Tao; Zhang, Ming-Zhen; Zhao, Yuan-Di; Liu, Bo

      2014-09-01

      A new type of multifunctional quantum dot (QD)-polypeptide hybrid nanogel with targeted imaging and drug delivery properties has been developed by metal-affinity driven self-assembly between artificial polypeptides and CdSe-ZnS core-shell QDs. On the surface of QDs, a tunable sandwich-like microstructure consisting of two hydrophobic layers and one hydrophilic layer between them was verified by capillary electrophoresis, transmission electron microscopy, and dynamic light scattering measurements. Hydrophobic and hydrophilic drugs can be simultaneously loaded in a QD-polypeptide nanogel. In vitro drug release of drug-loaded QD-polypeptide nanogels varies strongly with temperature, pH, and competitors. A drug-loaded QD-polypeptide nanogel with an arginine-glycine-aspartic acid (RGD) motif exhibited efficient receptor-mediated endocytosis in αvβ3 overexpressing HeLa cells but not in the control MCF-7 cells as analyzed by confocal microscopy and flow cytometry. In contrast, non-targeted QD-polypeptide nanogels revealed minimal binding and uptake in HeLa cells. Compared with the original QDs, the QD-polypeptide nanogels showed lower in vitro cytotoxicity for both HeLa cells and NIH 3T3 cells. Furthermore, the cytotoxicity of the targeted QD-polypeptide nanogel was lower for normal NIH 3T3 cells than that for HeLa cancer cells. These results demonstrate that the integration of imaging and drug delivery functions in a single QD-polypeptide nanogel has the potential for application in cancer diagnosis, imaging, and therapy.A new type of multifunctional quantum dot (QD)-polypeptide hybrid nanogel with targeted imaging and drug delivery properties has been developed by metal-affinity driven self-assembly between artificial polypeptides and CdSe-ZnS core-shell QDs. On the surface of QDs, a tunable sandwich-like microstructure consisting of two hydrophobic layers and one hydrophilic layer between them was verified by capillary electrophoresis, transmission electron

    11. Acid-responsive PEGylated doxorubicin prodrug nanoparticles for neuropilin-1 receptor-mediated targeted drug delivery.

      Science.gov (United States)

      Song, Huijuan; Zhang, Ju; Wang, Weiwei; Huang, Pingsheng; Zhang, Yumin; Liu, Jianfeng; Li, Chen; Kong, Deling

      2015-12-01

      Self-assembled prodrug nanoparticles have demonstrated great promise in cancer chemotherapy. In the present study, we developed a new kind of prodrug nanoparticles for targeted drug delivery. PEGylated doxorubicin conjugate with an acid-cleavable cis-aconityl spacer was prepared. Then it was functionalized with a tumor-penetrating peptide, Cys-Arg-Gly-Asp-Lys (CRGDK), providing the prodrug nanoparticles with the specific binding ability to neurophilin-1 receptor. In acid mediums, doxorubicin could be released from the prodrug nanoparticles with an accumulative release around 60% through the acid-triggered hydrolysis of cis-aconityl bond and nanoparticle disassembly. Whereas, drug release was slow under a neutral pH and the accumulative drug release was less than 16%. In the cell culture tests, our prodrug nanoparticles showed enhanced endocytosis and cytotoxicity in cancer cells including HepG2, MCF-7 and MDA-MB-231 cells, but lower cytotoxicity in human cardiomyocyte H2C9. In the animal experiments, the prodrug nanoparticles were intravenously injected into Balb/c nude mice bearing MDA-MB-231 tumors. Enhanced drug penetration and accumulation in tumors, accompanying with a rapid early tumor-binding behavior, was observed after intravenous injection of the peptide modified prodrug nanoparticles. These data suggests that the acid-sensitive and tumor-targeting PEGylated doxorubicin prodrug nanoparticle may be an efficient drug delivery system for cancer chemotherapy.

    12. Hepatocellular carcinoma: Will novel targeted drugs really impact the next future?

      Science.gov (United States)

      Montella, Liliana; Palmieri, Giovannella; Addeo, Raffaele; Del Prete, Salvatore

      2016-01-01

      Cancer treatment has been revolutionized by the advent of new molecular targeted and immunotherapeutic agents. Identification of the role of tumor angiogenesis changed the understanding of many tumors. After the unsuccessful results with chemotherapy, sorafenib, by interfering with angiogenic pathways, has become pivotal in the treatment of hepatocellular carcinoma. Sorafenib is the only systemic treatment to show a modest but statistically significant survival benefit. All novel drugs and strategies for treatment of advanced hepatocellular carcinoma must be compared with the results obtained with sorafenib, but no new drug or drug combination has yet achieved better results. In our opinion, the efforts to impact the natural history of the disease will be directed not only to drug development but also to understanding the underlying liver disease (usually hepatitis B virus- or hepatitis C virus-related) and to interrupting the progression of cirrhosis. It will be important to define the role and amount of mutations in the complex pathogenesis of hepatocellular carcinoma and to better integrate locoregional and systemic therapies. It will be important also to optimize the therapeutic strategies with existing chemotherapeutic drugs and new targeted agents.

    13. Drug targets for cell cycle dysregulators in leukemogenesis: in silico docking studies.

      Directory of Open Access Journals (Sweden)

      Archana Jayaraman

      Full Text Available Alterations in cell cycle regulating proteins are a key characteristic in neoplastic proliferation of lymphoblast cells in patients with Acute Lymphoblastic Leukemia (ALL. The aim of our study was to investigate whether the routinely administered ALL chemotherapeutic agents would be able to bind and inhibit the key deregulated cell cycle proteins such as--Cyclins E1, D1, D3, A1 and Cyclin Dependent Kinases (CDK 2 and 6. We used Schrödinger Glide docking protocol to dock the chemotherapeutic drugs such as Doxorubicin and Daunorubicin and others which are not very common including Clofarabine, Nelarabine and Flavopiridol, to the crystal structures of these proteins. We observed that the drugs were able to bind and interact with cyclins E1 and A1 and CDKs 2 and 6 while their docking to cyclins D1 and D3 were not successful. This binding proved favorable to interact with the G1/S cell cycle phase proteins that were examined in this study and may lead to the interruption of the growth of leukemic cells. Our observations therefore suggest that these drugs could be explored for use as inhibitors for these cell cycle proteins. Further, we have also highlighted residues which could be important in the designing of pharmacophores against these cell cycle proteins. This is the first report in understanding the mechanism of action of the drugs targeting these cell cycle proteins in leukemia through the visualization of drug-target binding and molecular docking using computational methods.

    14. Promises of novel multi-target neuroprotective and neurorestorative drugs for Parkinson's disease.

      Science.gov (United States)

      Youdim, Moussa B H; Kupershmidt, Lana; Amit, Tamar; Weinreb, Orly

      2014-01-01

      The cascade of neurotoxic events involved in neuronal degeneration suggests that it is naive to think mono-target drugs can induce disease modification by slowing the process of neurodegeneration in Parkinson's disease (PD). Employing the pharmacophore of rasagiline (N-propargyl-1-R-aminoindan), we have developed a series of novel multi-target neuroprotective drugs, including: (A) drugs [ladostigil, TV-3326 (N-propargyl-3R-aminoindan-5yl)-ethyl methylcarbamate)] with both cholinesterase-butyrylesterase (Ch-BuE) and brain-selective monamine oxidase-AB (MAO-AB) inhibitory activities and (B) iron chelator-radical scavenging drugs (M30) possessing brain-selective MAO-AB inhibitor activity and the neuroprotective-neurorescue propargylamine moiety of rasagiline. This was considered to be valid since brain MAO and iron increase in PD and aging, which could lead to oxidative stress-dependent neurodegeneration. The multi-target iron chelator, M30, has all the properties of ladostigil, but is not an acetylcholinesterase (CHE) inhibitor. However, M30 has both neuroprotective and neurorestorative activities for nigrostriatal dopamine neurons in post-lesion MPTP, lactacystin and 6-hydroxydopamine animal models of PD. The neurorestorative activity has been identified as being related to the ability of the drug to activate hypoxia-inducible factor (HIF) by inhibiting prolyl-4-hydroxylase. M30 regulates cell cycle arrest and induces the neurotrophins brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), erythropoietin (EPO), as well as glia-derived neurotrophic factor (GDNF). These unique multiple actions of M30 make it potentially useful as a disease modifying drug for the treatment of PD. PMID:24262165

    15. The anti-dementia drug candidate, (-)-clausenamide, improves memory impairment through its multi-target effect.

      Science.gov (United States)

      Chu, Shifeng; Liu, Shaolin; Duan, Wenzhen; Cheng, Yong; Jiang, Xueying; Zhu, Chuanjiang; Tang, Kang; Wang, Runsheng; Xu, Lin; Wang, Xiaoying; Yu, Xiaoming; Wu, Kemei; Wang, Yan; Wang, Muzou; Huang, Huiyong; Zhang, Juntian

      2016-06-01

      Multi-target drugs, such as the cocktail therapy used for treating AIDS, often show stronger efficacy than single-target drugs in treating complicated diseases. This review will focus on clausenamide (clau), a small molecule compound originally isolated from the traditional Chinese herbal medicine, Clausenalansium. The finding of four chiral centers in clau molecules predicted the presence of 16 clau enantiomers, including (-)-clau and (+)-clau. All of the predicted enantiomers have been successfully synthesized via innovative chemical approaches, and pharmacological studies have demonstrated (-)-clau as a eutomer and (+)-clau as a distomer in improving cognitive function in both normal physiological and pathological conditions. Mechanistically, the nootropic effect of (-)-clau is mediated by its multi-target actions, which include mild elevation of intracellular Ca(2+) concentrations, modulation of the cholinergic system, regulation of synaptic plasticity, and activation of cellular and molecular signaling pathways involved in learning and memory. Furthermore, (-)-clau suppresses the pathogenesis of Alzheimer's disease by inhibiting multiple etiological processes: (1) beta amyloid protein-induced intracellular Ca(2+) overload and apoptosis and (2) tau hyperphosphorylation and neurodegeneration. In conclusion, the nature of the multi-target actions of (-)-clau substantiates it as a promising chiral drug candidate for enhancing human cognition in normal conditions and treating memory impairment in neurodegenerative diseases. PMID:26812265

    16. Proteome scale comparative modeling for conserved drug and vaccine targets identification in Corynebacterium pseudotuberculosis.

      Science.gov (United States)

      Hassan, Syed Shah; Tiwari, Sandeep; Guimarães, Luís Carlos; Jamal, Syed Babar; Folador, Edson; Sharma, Neha Barve; de Castro Soares, Siomar; Almeida, Síntia; Ali, Amjad; Islam, Arshad; Póvoa, Fabiana Dias; de Abreu, Vinicius Augusto Carvalho; Jain, Neha; Bhattacharya, Antaripa; Juneja, Lucky; Miyoshi, Anderson; Silva, Artur; Barh, Debmalya; Turjanski, Adrian Gustavo; Azevedo, Vasco; Ferreira, Rafaela Salgado

      2014-01-01

      Corynebacterium pseudotuberculosis (Cp) is a pathogenic bacterium that causes caseous lymphadenitis (CLA), ulcerative lymphangitis, mastitis, and edematous to a broad spectrum of hosts, including ruminants, thereby threatening economic and dairy industries worldwide. Currently there is no effective drug or vaccine available against Cp. To identify new targets, we adopted a novel integrative strategy, which began with the prediction of the modelome (tridimensional protein structures for the proteome of an organism, generated through comparative modeling) for 15 previously sequenced C. pseudotuberculosis strains. This pan-modelomics approach identified a set of 331 conserved proteins having 95-100% intra-species sequence similarity. Next, we combined subtractive proteomics and modelomics to reveal a set of 10 Cp proteins, which may be essential for the bacteria. Of these, 4 proteins (tcsR, mtrA, nrdI, and ispH) were essential and non-host homologs (considering man, horse, cow and sheep as hosts) and satisfied all criteria of being putative targets. Additionally, we subjected these 4 proteins to virtual screening of a drug-like compound library. In all cases, molecules predicted to form favorable interactions and which showed high complementarity to the target were found among the top ranking compounds. The remaining 6 essential proteins (adk, gapA, glyA, fumC, gnd, and aspA) have homologs in the host proteomes. Their active site cavities were compared to the respective cavities in host proteins. We propose that some of these proteins can be selectively targeted using structure-based drug design approaches (SBDD). Our results facilitate the selection of C. pseudotuberculosis putative proteins for developing broad-spectrum novel drugs and vaccines. A few of the targets identified here have been validated in other microorganisms, suggesting that our modelome strategy is effective and can also be applicable to other pathogens. PMID:25573232

    17. Phage display:development of nanocarriers for targeted drug delivery to the brain

      Institute of Scientific and Technical Information of China (English)

      Babak Bakhshinejad; Marzieh Karimi; Mohammad Khalaj-Kondori

      2015-01-01

      The blood brain barrier represents a formidable obstacle for the transport of most systemati-cally administered neurodiagnostics and neurotherapeutics to the brain. Phage display is a high throughput screening strategy that can be used for the construction of nanomaterial peptide libraries. These libraries can be screened for ifnding brain targeting peptide ligands. Surface func-tionalization of a variety of nanocarriers with these brain homing peptides is a sophisticated way to develop nanobiotechnology-based drug delivery platforms that are able to cross the blood brain barrier. These efifcient drug delivery systems raise our hopes for the diagnosis and treatment of various brain disorders in the future.

    18. Biological characteristics of dengue virus and potential targets for drug design

      Institute of Scientific and Technical Information of China (English)

      Rui-feng Qi; Ling Zhang; Cheng-wu Chi

      2008-01-01

      Dengue infection is a major cause of morbidity in tropical and subtropical regions, bringing nearly 40% of the world population at risk and causing more than 20,000 deaths per year. But there is neither a vaccine for dengue disease nor antiviral drugs to treat the infection. In recent years, dengue infection has been particularly prevalent in India, Southeast Asia, Brazil, and Guangdong Province, China. In this article, we present a brief summary of the biological characteristics of dengue virus and associated flaviviruses, and outline the progress on studies of vaccines and drugs based on potential targets of the dengue virus.

    19. A folate-integrated magnetic polymer micelle for MRI and dual targeted drug delivery

      Science.gov (United States)

      Ao, Lijiao; Wang, Bi; Liu, Peng; Huang, Liang; Yue, Caixia; Gao, Duyang; Wu, Chunlei; Su, Wu

      2014-08-01

      This paper devotes a novel micellar structure for cancer theranostics by incorporating magnetic and therapeutic functionalities into a natural sourced targeting polymer vehicle. Heparin-folic acid micelles taking advantage of both excellent loading capability and cancer targeting ability have been employed to simultaneously incorporate superparamagnetic iron oxide nanoparticles (SPIONs) and doxorubicin through an ultrasonication-assisted microemulsion method. In this system, folic acids not only take the responsibility of micelle construction, but also facilitate cellular uptake due to their specific reorganization by MCF-7 cells over-expressing folate receptors. The obtained micelles exhibit good colloidal stability, a high magnetic content, considerable drug loading and sustained in vitro drug release. These clustered SPIONs exhibited high r2 relaxivity (243.65 mM-1 s-1) and further served as efficient probes for MR imaging. Notably, the transport efficiency of these micelles could be significantly improved under an external magnetic field, owing to their quick magnetic response. As a result, the as-proposed micelle shows great potential in multimodal theranostics, including active targeting, MRI diagnosis and drug delivery.This paper devotes a novel micellar structure for cancer theranostics by incorporating magnetic and therapeutic functionalities into a natural sourced targeting polymer vehicle. Heparin-folic acid micelles taking advantage of both excellent loading capability and cancer targeting ability have been employed to simultaneously incorporate superparamagnetic iron oxide nanoparticles (SPIONs) and doxorubicin through an ultrasonication-assisted microemulsion method. In this system, folic acids not only take the responsibility of micelle construction, but also facilitate cellular uptake due to their specific reorganization by MCF-7 cells over-expressing folate receptors. The obtained micelles exhibit good colloidal stability, a high magnetic content

    20. Pharmacological Targeting of AMP-Activated Protein Kinase and Opportunities for Computer-Aided Drug Design.

      Science.gov (United States)

      Miglianico, Marie; Nicolaes, Gerry A F; Neumann, Dietbert

      2016-04-14

      As a central regulator of metabolism, the AMP-activated protein kinase (AMPK) is an established therapeutic target for metabolic diseases. Beyond the metabolic area, the number of medical fields that involve AMPK grows continuously, expanding the potential applications for AMPK modulators. Even though indirect AMPK activators are used in the clinics for their beneficial metabolic outcome, the few described direct agonists all failed to reach the market to date, which leaves options open for novel targeting methods. As AMPK is not actually a single molecule and has different roles depending on its isoform composition, the opportunity for isoform-specific targeting has notably come forward, but the currently available modulators fall short of expectations. In this review, we argue that with the amount of available structural and ligand data, computer-based drug design offers a number of opportunities to undertake novel and isoform-specific targeting of AMPK. PMID:26510622

    1. Localization and distribution of magnetic chemotherapeutic drugs with magnetic targeting in rat brain

      Institute of Scientific and Technical Information of China (English)

      LI An-min; ZHANG Chuan-xiu; FU Xiang-ping; ZHANG Zhi-wen; XUE Qing-hui; YAN Run-min; YI Lin-hua

      2005-01-01

      Background Magnetic targeting therapy may be a new method for the treatment of malignent tumors. The purpose of this study was to investigate the localization and distribution of ferrofluid microsphere of human serum albumin methotrexate (FM-HSA-MTX) carriers in the brain and to explore the magnetic targeting chemotherapy for malignant brain tumor. Methods Ninety SD rats were divided into three groups: targeting group, non-magnetic targeting group, and control group. Synthesized FM-HSA-MTX carriers (MTX 25 mg/kg) were injected into the systemic circulation via the caudal vein (magnetic targeting group, n=30). A 0.6 T magnetic field was placed around the right hemisphere. The non-magnetic targeting group (n=30) was administered with FM-HSA-MTX without external magnetic field, meanwhile the control group (n=30) was treated with MTX and a magnetic field. Random serial sacrifices (n=10) were conducted at 15, 30 and 45 minutes after drug administration. Bilateral hemispheres were collected respectively, and analyzed for total MTX content. Results MTX content in the right hemisphere of the magnetic targeting group was significantly higher than that in the other two groups at 15, 30 and 45 minutes after drug administration (P<0.05) No difference was seen between the non-targeting group and control group. In the magnetic targeting group, MTX returned to the peak level [(0.564±0.018) mg/g, q15-45=32.252, P<0.05] 45 minutes after the injection but it deceased in the other two groups [non-magnetic targeting group: (0.060±0.015) mg/g, q15-45=9.245, P<0.05, control group: (0.074±0.045) mg/g, q15-45=6.299, P<0.05]. In the magnetic targeting group, the concentration of MTX in the right hemisphere was significantly higher than that in the left hemisphere (t45min=21.135, P=0.000) but no difference was observed between bilateral hemispheres in the other two groups (non-magnetic targeting group: t45min=0.434, P=0.670; control group: t45min=0.533, P=0.600). Conclusion In

    2. A RNA-DNA Hybrid Aptamer for Nanoparticle-Based Prostate Tumor Targeted Drug Delivery

      OpenAIRE

      Leach, John C.; Andrew Wang; Kaiming Ye; Sha Jin

      2016-01-01

      The side effects of radio- and chemo-therapy pose long-term challenges on a cancer patient’s health. It is, therefore, highly desirable to develop more effective therapies that can specifically target carcinoma cells without damaging normal and healthy cells. Tremendous efforts have been made in the past to develop targeted drug delivery systems for solid cancer treatment. In this study, a new aptamer, A10-3-J1, which recognizes the extracellular domain of the prostate specific membrane antig...

    3. Using mitochondrial sirtuins as drug targets: disease implications and available compounds.

      Science.gov (United States)

      Gertz, Melanie; Steegborn, Clemens

      2016-08-01

      Sirtuins are an evolutionary conserved family of NAD(+)-dependent protein lysine deacylases. Mammals have seven Sirtuin isoforms, Sirt1-7. They contribute to regulation of metabolism, stress responses, and aging processes, and are considered therapeutic targets for metabolic and aging-related diseases. While initial studies were focused on Sirt1 and 2, recent progress on the mitochondrial Sirtuins Sirt3, 4, and 5 has stimulated research and drug development for these isoforms. Here we review the roles of Sirtuins in regulating mitochondrial functions, with a focus on the mitochondrially located isoforms, and on their contributions to disease pathologies. We further summarize the compounds available for modulating the activity of these Sirtuins, again with a focus on mitochondrial isoforms, and we describe recent results important for the further improvement of compounds. This overview illustrates the potential of mitochondrial Sirtuins as drug targets and summarizes the status, progress, and challenges in developing small molecule compounds modulating their activity. PMID:27007507

    4. Virus-encoded chemokine receptors--putative novel antiviral drug targets

      DEFF Research Database (Denmark)

      Rosenkilde, Mette M

      2005-01-01

      Large DNA viruses, in particular herpes- and poxviruses, have evolved proteins that serve as mimics or decoys for endogenous proteins in the host. The chemokines and their receptors serve key functions in both innate and adaptive immunity through control of leukocyte trafficking, and have...... to their closest endogenous homologs, are interactions with a wider range of chemokines, which can act as agonists, antagonists and inverse agonists, and the exploitation of many signal transduction pathways. High constitutive activity is another key property of some--but not all--of these receptors. The chemokine...... receptors belong to the superfamily of G-protein coupled 7TM receptors that per se are excellent drug targets. At present, non-peptide antagonists have been developed against many chemokine receptors. The potentials of the virus-encoded chemokine receptors as drug targets--ie. as novel antiviral strategies...

    5. Targeting imperfect vaccines against drug-resistance determinants: a strategy for countering the rise of drug resistance.

      Directory of Open Access Journals (Sweden)

      Regina Joice

      Full Text Available The growing prevalence of antimicrobial resistance in major pathogens is outpacing discovery of new antimicrobial classes. Vaccines mitigate the effect of antimicrobial resistance by reducing the need for treatment, but vaccines for many drug-resistant pathogens remain undiscovered or have limited efficacy, in part because some vaccines selectively favor pathogen strains that escape vaccine-induced immunity. A strain with even a modest advantage in vaccinated hosts can have high fitness in a population with high vaccine coverage, which can offset a strong selection pressure such as antimicrobial use that occurs in a small fraction of hosts. We propose a strategy to target vaccines against drug-resistant pathogens, by using resistance-conferring proteins as antigens in multicomponent vaccines. Resistance determinants may be weakly immunogenic, offering only modest specific protection against resistant strains. Therefore, we assess here how varying the specific efficacy of the vaccine against resistant strains would affect the proportion of drug-resistant vs. -sensitive strains population-wide for three pathogens--Streptococcus pneumoniae, Staphylococcus aureus, and influenza virus--in which drug resistance is a problem. Notably, if such vaccines confer even slightly higher protection (additional efficacy between 1% and 8% against resistant variants than sensitive ones, they may be an effective tool in controlling the rise of resistant strains, given current levels of use for many antimicrobial agents. We show that the population-wide impact of such vaccines depends on the additional effect on resistant strains and on the overall effect (against all strains. Resistance-conferring accessory gene products or resistant alleles of essential genes could be valuable as components of vaccines even if their specific protective effect is weak.

    6. Comparative genomics allowed the identification of drug targets against human fungal pathogens

      Directory of Open Access Journals (Sweden)

      Martins Natalia F

      2011-01-01

      Full Text Available Abstract Background The prevalence of invasive fungal infections (IFIs has increased steadily worldwide in the last few decades. Particularly, there has been a global rise in the number of infections among immunosuppressed people. These patients present severe clinical forms of the infections, which are commonly fatal, and they are more susceptible to opportunistic fungal infections than non-immunocompromised people. IFIs have historically been associated with high morbidity and mortality, partly because of the limitations of available antifungal therapies, including side effects, toxicities, drug interactions and antifungal resistance. Thus, the search for alternative therapies and/or the development of more specific drugs is a challenge that needs to be met. Genomics has created new ways of examining genes, which open new strategies for drug development and control of human diseases. Results In silico analyses and manual mining selected initially 57 potential drug targets, based on 55 genes experimentally confirmed as essential for Candida albicans or Aspergillus fumigatus and other 2 genes (kre2 and erg6 relevant for fungal survival within the host. Orthologs for those 57 potential targets were also identified in eight human fungal pathogens (C. albicans, A. fumigatus, Blastomyces dermatitidis, Paracoccidioides brasiliensis, Paracoccidioides lutzii, Coccidioides immitis, Cryptococcus neoformans and Histoplasma capsulatum. Of those, 10 genes were present in all pathogenic fungi analyzed and absent in the human genome. We focused on four candidates: trr1 that encodes for thioredoxin reductase, rim8 that encodes for a protein involved in the proteolytic activation of a transcriptional factor in response to alkaline pH, kre2 that encodes for α-1,2-mannosyltransferase and erg6 that encodes for Δ(24-sterol C-methyltransferase. Conclusions Our data show that the comparative genomics analysis of eight fungal pathogens enabled the identification of

    7. Aptamers as targeting delivery devices or anti-cancer drugs for fighting tumors.

      Science.gov (United States)

      Scaggiante, Bruna; Dapas, Barbara; Farra, Rossella; Grassi, Mario; Pozzato, Gabriele; Giansante, Carlo; Fiotti, Nicola; Tamai, Elisa; Tonon, Federica; Grassi, Gabriele

      2013-06-01

      Aptamer researches applied to the treatment of human cancers have increased since their discovery in 1990. This is due to different factors including: 1) the technical possibility to select, by SELEX-based procedures, specific aptamers targeting virtually any given molecule, 2) the aptamer favorable bio-activity in vivo, 3) the low production costs and 4) the ease synthesis and storage for the marketing. In the field of cancer treatments, aptamers have been studied as tumor-specific agents driving drugs into cancer cells; additionally they have been used as anti-neoplastic agents, able to inhibit tumor cell growth and dissemination when administered alone or in combination with conventional anti-neoplastic drugs. Aptamers are gaining an increased interest for pharmaceutical companies and some of them are under clinical evaluation trials. In this review we update the findings about the use of aptamers as "escort" molecules able to drive drugs into the cells and as antineoplastic drugs. Current anti-neoplastic treatments suffer from the intrinsic toxicity related to the un-specific targeting of both normal and tumorigenic proliferating cells. The aptamers could be useful to improve: 1) the selective targeting of molecules essential for the viability and expansion of tumor cells and/or the selective driving of chemotherapies into tumor cells, thus resulting in higher effectiveness and lower systemic side-effects compared to conventional anti-neoplastic drugs alone and 2) to improve the therapeutic index of currently used chemotherapies. Even if some problems related to the in vivo stability and pharmacokinetic/dynamics of aptamers remain to be improved, their potential use in the treatment of different human cancers is getting closer and closer to a practical therapeutic use. PMID:23687927

    8. A target repurposing approach identifies N-myristoyltransferase as a new candidate drug target in filarial nematodes.

      Directory of Open Access Journals (Sweden)

      Brendan D Galvin

      2014-09-01

      Full Text Available Myristoylation is a lipid modification involving the addition of a 14-carbon unsaturated fatty acid, myristic acid, to the N-terminal glycine of a subset of proteins, a modification that promotes their binding to cell membranes for varied biological functions. The process is catalyzed by myristoyl-CoA:protein N-myristoyltransferase (NMT, an enzyme which has been validated as a drug target in human cancers, and for infectious diseases caused by fungi, viruses and protozoan parasites. We purified Caenorhabditis elegans and Brugia malayi NMTs as active recombinant proteins and carried out kinetic analyses with their essential fatty acid donor, myristoyl-CoA and peptide substrates. Biochemical and structural analyses both revealed that the nematode enzymes are canonical NMTs, sharing a high degree of conservation with protozoan NMT enzymes. Inhibitory compounds that target NMT in protozoan species inhibited the nematode NMTs with IC50 values of 2.5-10 nM, and were active against B. malayi microfilariae and adult worms at 12.5 µM and 50 µM respectively, and C. elegans (25 µM in culture. RNA interference and gene deletion in C. elegans further showed that NMT is essential for nematode viability. The effects observed are likely due to disruption of the function of several downstream target proteins. Potential substrates of NMT in B. malayi are predicted using bioinformatic analysis. Our genetic and chemical studies highlight the importance of myristoylation in the synthesis of functional proteins in nematodes and have shown for the first time that NMT is required for viability in parasitic nematodes. These results suggest that targeting NMT could be a valid approach for the development of chemotherapeutic agents against nematode diseases including filariasis.

    9. A target repurposing approach identifies N-myristoyltransferase as a new candidate drug target in filarial nematodes.

      Science.gov (United States)

      Galvin, Brendan D; Li, Zhiru; Villemaine, Estelle; Poole, Catherine B; Chapman, Melissa S; Pollastri, Michael P; Wyatt, Paul G; Carlow, Clotilde K S

      2014-09-01

      Myristoylation is a lipid modification involving the addition of a 14-carbon unsaturated fatty acid, myristic acid, to the N-terminal glycine of a subset of proteins, a modification that promotes their binding to cell membranes for varied biological functions. The process is catalyzed by myristoyl-CoA:protein N-myristoyltransferase (NMT), an enzyme which has been validated as a drug target in human cancers, and for infectious diseases caused by fungi, viruses and protozoan parasites. We purified Caenorhabditis elegans and Brugia malayi NMTs as active recombinant proteins and carried out kinetic analyses with their essential fatty acid donor, myristoyl-CoA and peptide substrates. Biochemical and structural analyses both revealed that the nematode enzymes are canonical NMTs, sharing a high degree of conservation with protozoan NMT enzymes. Inhibitory compounds that target NMT in protozoan species inhibited the nematode NMTs with IC50 values of 2.5-10 nM, and were active against B. malayi microfilariae and adult worms at 12.5 µM and 50 µM respectively, and C. elegans (25 µM) in culture. RNA interference and gene deletion in C. elegans further showed that NMT is essential for nematode viability. The effects observed are likely due to disruption of the function of several downstream target proteins. Potential substrates of NMT in B. malayi are predicted using bioinformatic analysis. Our genetic and chemical studies highlight the importance of myristoylation in the synthesis of functional proteins in nematodes and have shown for the first time that NMT is required for viability in parasitic nematodes. These results suggest that targeting NMT could be a valid approach for the development of chemotherapeutic agents against nematode diseases including filariasis.

    10. IGF-1 receptor targeted nanoparticles for image-guided therapy of stroma-rich and drug resistant human cancer

      Science.gov (United States)

      Zhou, Hongyu; Qian, Weiping; Uckun, Fatih M.; Zhou, Zhiyang; Wang, Liya; Wang, Andrew; Mao, Hui; Yang, Lily

      2016-05-01

      Low drug delivery efficiency and drug resistance from highly heterogeneous cancer cells and tumor microenvironment represent major challenges in clinical oncology. Growth factor receptor, IGF-1R, is overexpressed in both human tumor cells and tumor associated stromal cells. The level of IGF-1R expression is further up-regulated in drug resistant tumor cells. We have developed IGF-1R targeted magnetic iron oxide nanoparticles (IONPs) carrying multiple anticancer drugs into human tumors. This IGF-1R targeted theranostic nanoparticle delivery system has an iron core for non-invasive MR imaging, amphiphilic polymer coating to ensure the biocompatibility as well as for drug loading and conjugation of recombinant human IGF-1 as targeting molecules. Chemotherapy drugs, Doxorubicin (Dox), was encapsulated into the polymer coating and/or conjugated to the IONP surface by coupling with the carboxyl groups. The ability of IGF1R targeted theranostic nanoparticles to penetrate tumor stromal barrier and enhance tumor cell killing has been demonstrated in human pancreatic cancer patient tissue derived xenograft (PDX) models. Repeated systemic administrations of those IGF-1R targeted theranostic IONP carrying Dox led to breaking the tumor stromal barrier and improved therapeutic effect. Near infrared (NIR) optical and MR imaging enabled noninvasive monitoring of nanoparticle-drug delivery and therapeutic responses. Our results demonstrated that IGF-1R targeted nanoparticles carrying multiple drugs are promising combination therapy approaches for image-guided therapy of stroma-rich and drug resistant human cancer, such as pancreatic cancer.

    11. Pharmacogenomic association study on the role of drug metabolizing, drug transporters and drug target gene polymorphisms in drug-resistant epilepsy in a north Indian population

      OpenAIRE

      Ritu Kumari; Ram Lakhan; Garg, R. K.; Kalita, J; Misra, U K; Balraj Mittal

      2011-01-01

      Background: In epilepsy, in spite of the best possible medications and treatment protocols, approximately one-third of the patients do not respond adequately to anti-epileptic drugs. Such interindividual variations in drug response are believed to result from genetic variations in candidate genes belonging to multiple pathways. Materials and Methods: In the present pharmacogenetic analysis, a total of 402 epilepsy patients were enrolled. Of them, 128 were diagnosed as multiple drug-resist...

    12. Chemoattractant receptors in drug discovery: FPR2 and CCR2-two potential targets

      OpenAIRE

      Kalderén, Christina

      2012-01-01

      Chemoattractants and chemoattractant receptors have many important functions in multicellular organisms, not least for their role in regulating migration of leukocytes. The receptors are also involved in many pathologies and they have, since they were cloned in the 1990ies, been regarded as attractive targets for development of drugs against cancer, viral infections, and inflammatory/autoimmune diseases. Although chemotactic molecules are very heterogeneous in terms of chemi...

    13. Targeting sigma receptors: novel medication development for drug abuse and addiction

      OpenAIRE

      Matsumoto, Rae R.

      2009-01-01

      Psychostimulant abuse is a serious health and societal problem in industrialized and developing countries. However, the identification of an effective pharmacotherapy to treat it has remained elusive. It has long been known that many psychostimulant drugs, including cocaine and methamphetamine, interact with sigma receptors in the brain and heart, offering a logical target for medication development efforts. However, selective pharmacological agents and molecular biological tools have only re...

    14. A dual-targeting drug co-delivery system for tumor chemo- and gene combined therapy.

      Science.gov (United States)

      Zhang, Fangrong; Li, Min; Su, Yujie; Zhou, Jianping; Wang, Wei

      2016-07-01

      Regulation of gene expression using p53 is a promising strategy for treatment of numerous cancers, and chemotherapeutic drug dichloroacetate (DCA) induces apoptosis and growth inhibition in tumor, without apparent toxicity in normal tissues. Combining DCA and p53 gene could be an effective way to treat tumors. The progress towards broad applications of DCA/p53 combination requires the development of safe and efficient vectors that target to specific cells. In this study, we developed a DSPE-PEG-AA (1,2-distearoryl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol-2000)] ammonium salt-anisamide) modified reconstituted high-density lipoprotein-based DCA/p53-loaded nanoparticles (DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes), which was fabricated as a drug/gene dual-targeting co-delivery system for potential cancer therapy. Here, DCA-PEI was utilized to effectively condense the p53 plasmid, to incorporate the plasmid into rHDL and to act as an antitumor drug to inhibit tumor cell growth. The DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes exhibited desirable and homogenous particle size, neutral surface charge and low cytotoxicity for normal cells in vitro. The results of confocal laser scanning microscopy (CLSM) and flow cytometry confirmed that the scavenger receptor class B type I (SR-BI) and sigma receptor mediated dual-targeting function of the complexes inducing efficient cytoplasmic drug delivery and gene transfection in human lung adenocarcinoma cell line A549. And in vivo investigation on nude mice bearing A549 tumor xenografts revealed that DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes possessed specific tumor targeting and strong antitumor activity. The work described here demonstrated that the DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes might offer a promising tool for effective cancer therapy. PMID:27127046

    15. Targeted drug delivery across the blood–brain barrier using ultrasound technique

      OpenAIRE

      Deng, Cheri X.

      2010-01-01

      Effective delivery of therapeutic agents into the brain can greatly improve the treatments of neurological and neurodegenerative diseases. Application of focused ultrasound facilitated by microbubbles has shown the potential to deliver drugs across the blood–brain barrier into targeted sites within the brain noninvasively. This review provides a summary of the technological background and principle, highlights of recent significant developments and research progress, as well as a critical com...

    16. Targeting oncoprotein stability overcomes drug resistance caused by FLT3 kinase domain mutations.

      Directory of Open Access Journals (Sweden)

      Chuanjiang Yu

      Full Text Available FLT3 is the most frequently mutated kinase in acute myeloid leukemia (AML. Internal tandem duplications (ITDs in the juxta-membrane region constitute the majority of activating FLT3 mutations. Several FLT3 kinase inhibitors were developed and tested in the clinic with significant success. However, recent studies have reported the development of secondary drug resistance in patients treated with FLT3 inhibitors. Since FLT3-ITD is an HSP90 client kinase, we here explored if targeting the stability of drug-resistant FLT3 mutant protein could be a potential therapeutic option. We observed that HSP90 inhibitor treatment resulted in the degradation of inhibitor-resistant FLT3-ITD mutants and selectively induced toxicity in cells expressing FLT3-ITD mutants. Thus, HSP90 inhibitors provide a potential therapeutic choice to overcome secondary drug resistance following TKI treatment in FLT3-ITD positive AML.

    17. In silico characterization of putative drug targets in Staphylococcus saprophyticus, causing bovine mastitis.

      Science.gov (United States)

      Bhasme, Pramod C; Kurjogi, Mahantesh M; Sanakal, Rajeshwari D; Kaliwal, Rohit B; Kaliwal, Basappa B

      2013-01-01

      The bovine mastitis caused by coagulase negative staphylococci (CNS) has increased in many herds of urban and rural areas of India. Emergence of multi drug resistant bacteria has further made its management more complex and serious. Therefore, innovation of novel specific drug for the treatment of disease caused by particular organism remained to be a challenge. Hence, in the present study a bacterium was isolated from milk of the cow with bovine mastitis and was identified as S. saprophyticus, 44 pathways of S. saprophyticus retrieved (KEGG) from web server were found to be non homologous to the host Bos taurus, out of which 39 pathways were found to be in cytoplasm, 2 in cell wall and 3 in the cell membrane. The knowledge of the present study could make the drug discovery easier which have high affinity to the target site of the causative organism.

    18. Recombinant human elastin-like magnetic microparticles for drug delivery and targeting.

      Science.gov (United States)

      Ciofani, Gianni; Genchi, Giada Graziana; Guardia, Pablo; Mazzolai, Barbara; Mattoli, Virgilio; Bandiera, Antonella

      2014-05-01

      Bioinspired recombinant polypeptides represent a highly promising tool in biomedical research, being protein intrinsic constituents of both cells and their natural matrices. In this regard, a very interesting model is represented by polypeptides inspired by elastin, which naturally confers rubber-like elasticity to tissues, and is able to undergo wide deformations without rupture. In this paper, a microparticle system based on a recombinant human elastin-like polypeptide (HELP) is reported for drug delivery applications. HELP microparticles are prepared through a water-in-oil emulsion of an aqueous solution of recombinant polypeptide in isoctane, followed by enzymatic cross-linking. Superparamagnetic iron oxide nanoparticles are introduced in this system with the purpose of conferring magnetic properties to the microspheres, and thus controlling their targeting and tracking as drug vectors. The obtained microparticles are characterized in terms of morphology, structure, magnetic properties, drug release, and magnetic drivability, showing interesting and promising results for further biomedical applications. PMID:24318291

    19. Hyaluronic acid modified mesoporous silica nanoparticles for targeted drug delivery to CD44-overexpressing cancer cells

      Science.gov (United States)

      Yu, Meihua; Jambhrunkar, Siddharth; Thorn, Peter; Chen, Jiezhong; Gu, Wenyi; Yu, Chengzhong

      2012-12-01

      In this paper, a targeted drug delivery system has been developed based on hyaluronic acid (HA) modified mesoporous silica nanoparticles (MSNs). HA-MSNs possess a specific affinity to CD44 over-expressed on the surface of a specific cancer cell line, HCT-116 (human colon cancer cells). The cellular uptake performance of fluorescently labelled MSNs with and without HA modification has been evaluated by confocal microscopy and fluorescence-activated cell sorter (FACS) analysis. Compared to bare MSNs, HA-MSNs exhibit a higher cellular uptake via HA receptor mediated endocytosis. An anticancer drug, doxorubicin hydrochloride (Dox), has been loaded into MSNs and HA-MSNs as drug delivery vehicles. Dox loaded HA-MSNs show greater cytotoxicity to HCT-116 cells than free Dox and Dox-MSNs due to the enhanced cell internalization behavior of HA-MSNs. It is expected that HA-MSNs have a great potential in targeted delivery of anticancer drugs to CD44 over-expressing tumors.

    20. Electrosprayed nanocomposites based on hyaluronic acid derivative and Soluplus for tumor-targeted drug delivery.

      Science.gov (United States)

      Lee, Song Yi; Lee, Jeong-Jun; Park, Ju-Hwan; Lee, Jae-Young; Ko, Seung-Hak; Shim, Jae-Seong; Lee, Jongkook; Heo, Moon Young; Kim, Dae-Duk; Cho, Hyun-Jong

      2016-09-01

      Nanocomposite (NC) based on hyaluronic acid-ceramide (HACE) and Soluplus (SP) was fabricated by electrospraying for the tumor-targeted delivery of resveratrol (RSV). Amphiphilic property of both HACE and SP has been used to entrap RSV in the internal cavity of NC. Electrospraying with established experimental conditions produced HACE/SP/RSV NC with 230nm mean diameter, narrow size distribution, negative zeta potential, and >80% drug entrapment efficiency. Sustained and pH-dependent drug release profiles were observed in drug release test. Cellular uptake efficiency of HACE/SP NC was higher than that of SP NC, mainly based on HA-CD44 receptor interaction, in MDA-MB-231 (CD44 receptor-positive human breast cancer) cells. Selective tumor targetability of HACE/SP NC, compared to SP NC, was also confirmed in MDA-MB-231 tumor-xenograted mouse model using a near-infrared fluorescence (NIRF) imaging. According to the results of pharmacokinetic study in rats, decreased in vivo clearance and increased half-life of RSV in NC group, compared to drug solution group, were shown. Given that these experimental results, developed HACE/SP NC can be a promising theranostic nanosystem for CD44 receptor-expressed cancers. PMID:27208440

    1. Folate-conjugated boron nitride nanospheres for targeted delivery of anticancer drugs

      Science.gov (United States)

      Feng, Shini; Zhang, Huijie; Yan, Ting; Huang, Dandi; Zhi, Chunyi; Nakanishi, Hideki; Gao, Xiao-Dong

      2016-01-01

      With its unique physical and chemical properties and structural similarity to carbon, boron nitride (BN) has attracted considerable attention and found many applications. Biomedical applications of BN have recently started to emerge, raising great hopes in drug and gene delivery. Here, we developed a targeted anticancer drug delivery system based on folate-conjugated BN nanospheres (BNNS) with receptor-mediated targeting. Folic acid (FA) was successfully grafted onto BNNS via esterification reaction. In vitro cytotoxicity assay showed that BNNS-FA complexes were non-toxic to HeLa cells up to a concentration of 100 μg/mL. Then, doxorubicin hydrochloride (DOX), a commonly used anticancer drug, was loaded onto BNNS-FA complexes. BNNS-FA/DOX complexes were stable at pH 7.4 but effectively released DOX at pH 5.0, which exhibited a pH sensitive and sustained release pattern. BNNS-FA/DOX complexes could be recognized and specifically internalized by HeLa cells via FA receptor-mediated endocytosis. BNNS-FA/DOX complexes exhibited greater cytotoxicity to HeLa cells than free DOX and BNNS/DOX complexes due to the increased cellular uptake of DOX mediated by the FA receptor. Therefore, BNNS-FA complexes had strong potential for targeted cancer therapy. PMID:27695318

    2. Pegylated polyelectrolyte nanoparticles containing paclitaxel as a promising candidate for drug carriers for passive targeting.

      Science.gov (United States)

      Szczepanowicz, Krzysztof; Bzowska, Monika; Kruk, Tomasz; Karabasz, Alicja; Bereta, Joanna; Warszynski, Piotr

      2016-07-01

      Targeted drug delivery systems are of special importance in cancer therapies, since serious side effects resulting from unspecific accumulation of highly toxic chemotherapeutics in healthy tissues can restrict effectiveness of the therapy. In this work we present the method of preparing biocompatible, polyelectrolyte nanoparticles containing the anticancer drug that may serve as a vehicle for passive tumor targeting. The nanoparticles were prepared via direct encapsulation of emulsion droplets in a polyelectrolyte multilayer shell. The oil cores that contained paclitaxel were stabilized by docusate sodium salt/poly-l-lysine surface complex (AOT/PLL) and were encapsulated in shells formed by the LbL adsorption of biocompatible polyelectrolytes, poly-L-glutamic acid (PGA) and PLL up to 5 or 6 layers. The surface of the nanoparticles was pegylated through the adsorption of the pegylated polyelectrolyte (PGA-g-PEG) as the outer layer to prolong the persistence of the nanocarriers in the circulation. The synthesized nanoparticles were stable in cell culture medium containing serum and their average size was 100nm, which makes them promising candidates for passive targeted drug delivery. This notion was further confirmed by the results of studying the biological effects of nanoformulations on two tumor cell lines: mouse colon carcinoma cell line CT26-CEA and the mouse mammary carcinoma cell line 4T1. The empty polyelectrolyte nanoparticles did not affect the viability of the tested cells, whereas encapsulated paclitaxel retained its strong cytotoxic/cytostatic activity. PMID:27037784

    3. A Trimodal Closomer Drug-Delivery System Tailored with Tracing and Targeting Capabilities.

      Science.gov (United States)

      Sarma, Saurav J; Khan, Aslam A; Goswami, Lalit N; Jalisatgi, Satish S; Hawthorne, M Frederick

      2016-08-26

      The construction and application of a unique monodisperse closomer drug-delivery system (CDDS) integrating three different functionalities onto an icosahedral closo-dodecaborane [B12 ](2-) scaffold is described. Eleven B-OH vertices of [closo-B12 (OH)12 ](2-) were used to attach eleven copies of the anticancer drug chlorambucil and the targeting vector glucosamine through a bifurcating lysine linker. The remaining twelfth vertex was used to attach a fluorescent imaging probe. The presence of multiple glucosamine units offered a monodisperse and highly water-soluble CDDS with a high payload of therapeutic cargo. This array enhanced the penetration of the drug into cancer cells by exploiting the overexpression of GLUT-1 receptors present on cancer cells. About 15-fold enhancement in cytotoxicity was observed for CDDS-1 against Jurkat cells, compared to CDDS-2, which lacks the GLUT-1 targeting glucosamine. A cytotoxicity comparison of CDDS-1 against colorectal RKO cells and its GLUT-1 knock-out version confirmed that GLUT-1 mediates endocytosis. Using fluorescent markers both CDDS-1 and -2 were traced to the mitochondria, a novel target for alkylating agents.

    4. Tools for the rational design of bivalent microtubule-targeting drugs.

      Science.gov (United States)

      Marangon, Jacopo; Christodoulou, Michael S; Casagrande, Fancesca V M; Tiana, Guido; Dalla Via, Lisa; Aliverti, Alessandro; Passarella, Daniele; Cappelletti, Graziella; Ricagno, Stefano

      2016-10-01

      Microtubule (MT) dynamic behaviour is an attractive drug target for chemotherapy, whose regulation by MT-stabilizing and destabilizing agents has been fruitfully applied in treating several types of cancers. MT-stabilizing agents are also emerging as potential remedies for neurodegenerative conditions, such as Alzheimer's and Parkinson's disease, although single-target drugs are not expected to fully cure these complex pathologies. Drug combination often displays enhanced efficacy with respect to mono-therapies. In particular, MT-targeting bivalent compounds (MTBCs) represent a promising class of molecules; however, surprisingly, the majority of MTBCs reported so far exhibit equal if not less efficacy than their building monomers. In order to shed light on MTBCs poor performance, we characterised through a set of complementary approaches thiocolchine (TH) and two bivalent TH-homodimers as prototype molecules. First, the binding affinities of these three molecules were assessed, then we obtained the crystallographic structure of a tubulin-TH complex. The binding affinities were interpreted in light of structural data and of molecular dynamics simulations. Finally, their effects on MT cytoskeleton and cell survival were validated on HeLa cells. The ensemble of these data provides chemical and structural considerations on how a successful rational design of MTBCs should be conceived.

    5. Development of high drug-loading nanomicelles targeting steroids to the brain.

      Science.gov (United States)

      Zheng, Sijia; Xie, Yanqi; Li, Yuan; Li, Ling; Tian, Ning; Zhu, Wenbo; Yan, Guangmei; Wu, Chuanbin; Hu, Haiyan

      2014-01-01

      The objective of this research was to develop and evaluate high drug-loading ligand-modified nanomicelles to deliver a steroidal compound to the brain. YC1 (5α-cholestane-24-methylene-3β, 5α, 6β, 19-tetraol), with poor solubility and limited access to the brain, for the first time, has been proved to be an effective neuroprotective steroid by our previous studies. Based on the principle of 'like dissolves like', cholesterol, which shares the same steroidal parent nucleus with YC1, was selected to react with sodium alginate, producing amphiphilic sodium alginate- cholesterol derivatives (SACDs). To increase the grafting ratio and drug loading, cholesterol was converted to cholesteryl chloroformate, for the first time, before reacting with sodium alginate. Further, lactoferrin was conjugated on SACDs to provide lactoferrin-SACDs (Lf-SACD), which was established by immune electron microscopy (IEM) and self-assembled into brain-targeting nanomicelles. These nanomicelles were negatively charged and spherical in nature, with an average size of drug loading was increased due to the cholesteryl inner cores of the nanomicelles, and the higher the grafting ratio was, the lower the critical micelle concentration (CMC) value of SACD, and the higher drug loading. The in vitro drug release, studied by bulk-equilibrium dialysis in 20 mL of 6% hydroxypropyl-β-cyclodextrin solution at 37°C, indicated a prolonged release profile. The YC1 concentration in mouse brain delivered by lactoferrin-modified nanomicelles was higher than in those delivered by non-modified nanomicelles and YC1 solution. The unique brain-targeting nanomicelle system may provide a promising carrier to deliver hydrophobic drugs across the blood-brain barrier for the treatment of brain diseases.

    6. Novel therapeutic approaches for pulmonary arterial hypertension: Unique molecular targets to site-specific drug delivery.

      Science.gov (United States)

      Vaidya, Bhuvaneshwar; Gupta, Vivek

      2015-08-10

      Pulmonary arterial hypertension (PAH) is a cardiopulmonary disorder characterized by increased blood pressure in the small arterioles supplying blood to lungs for oxygenation. Advances in understanding of molecular and cellular biology techniques have led to the findings that PAH is indeed a cascade of diseases exploiting multi-faceted complex pathophysiology, with cellular proliferation and vascular remodeling being the key pathogenic events along with several cellular pathways involved. While current therapies for PAH do provide for amelioration of disease symptoms and acute survival benefits, their full therapeutic potential is hindered by patient incompliance and off-target side effects. To overcome the issues related with current therapy and to devise a more selective therapy, various novel pathways are being investigated for PAH treatment. In addition, inability to deliver anti-PAH drugs to the disease site i.e., distal pulmonary arterioles has been one of the major challenges in achieving improved patient outcomes and improved therapeutic efficacy. Several novel carriers have been explored to increase the selectivity of currently approved anti-PAH drugs and to act as suitable carriers for the delivery of investigational drugs. In the present review, we have discussed potential of various novel molecular pathways/targets including RhoA/Rho kinase, tyrosine kinase, endothelial progenitor cells, vasoactive intestinal peptide, and miRNA in PAH therapeutics. We have also discussed various techniques for site-specific drug delivery of anti-PAH therapeutics so as to improve the efficacy of approved and investigational drugs. This review will provide gainful insights into current advances in PAH therapeutics with an emphasis on site-specific drug payload delivery.

    7. Adverse drug reaction prediction using scores produced by large-scale drug-protein target docking on high-performance computing machines.

      Directory of Open Access Journals (Sweden)

      Montiago X LaBute

      Full Text Available Late-stage or post-market identification of adverse drug reactions (ADRs is a significant public health issue and a source of major economic liability for drug development. Thus, reliable in silico screening of drug candidates for possible ADRs would be advantageous. In this work, we introduce a computational approach that predicts ADRs by combining the results of molecular docking and leverages known ADR information from DrugBank and SIDER. We employed a recently parallelized version of AutoDock Vina (VinaLC to dock 906 small molecule drugs to a virtual panel of 409 DrugBank protein targets. L1-regularized logistic regression models were trained on the resulting docking scores of a 560 compound subset from the initial 906 compounds to predict 85 side effects, grouped into 10 ADR phenotype groups. Only 21% (87 out of 409 of the drug-protein binding features involve known targets of the drug subset, providing a significant probe of off-target effects. As a control, associations of this drug subset with the 555 annotated targets of these compounds, as reported in DrugBank, were used as features to train a separate group of models. The Vina off-target models and the DrugBank on-target models yielded comparable median area-under-the-receiver-operating-characteristic-curves (AUCs during 10-fold cross-validation (0.60-0.69 and 0.61-0.74, respectively. Evidence was found in the PubMed literature to support several putative ADR-protein associations identified by our analysis. Among them, several associations between neoplasm-related ADRs and known tumor suppressor and tumor invasiveness marker proteins were found. A dual role for interstitial collagenase in both neoplasms and aneurysm formation was also identified. These associations all involve off-target proteins and could not have been found using available drug/on-target interaction data. This study illustrates a path forward to comprehensive ADR virtual screening that can potentially scale with

    8. Targeting choroid plexus epithelia and ventricular ependyma for drug delivery to the central nervous system

      Directory of Open Access Journals (Sweden)

      Stopa Edward G

      2011-01-01

      Full Text Available Abstract Background Because the choroid plexus (CP is uniquely suited to control the composition of cerebrospinal fluid (CSF, there may be therapeutic benefits to increasing the levels of biologically active proteins in CSF to modulate central nervous system (CNS functions. To this end, we sought to identify peptides capable of ligand-mediated targeting to CP epithelial cells reasoning that they could be exploited to deliver drugs, biotherapeutics and genes to the CNS. Methods A peptide library displayed on M13 bacteriophage was screened for ligands capable of internalizing into CP epithelial cells by incubating phage with CP explants for 2 hours at 37C and recovering particles with targeting capacity. Results Three peptides, identified after four rounds of screening, were analyzed for specific and dose dependant binding and internalization. Binding was deemed specific because internalization was prevented by co-incubation with cognate synthetic peptides. Furthermore, after i.c.v. injection into rat brains, each peptide was found to target phage to epithelial cells in CP and to ependyma lining the ventricles. Conclusion These data demonstrate that ligand-mediated targeting can be used as a strategy for drug delivery to the central nervous system and opens the possibility of using the choroid plexus as a portal of entry into the brain.

    9. Peptide Phage Display as a Tool for Drug Discovery: Targeting Membrane Receptors

      Directory of Open Access Journals (Sweden)

      Tomaz Bratkovic

      2011-01-01

      Full Text Available Ligands selected from phage-displayed random peptide libraries tend to be directed to biologically relevant sites on the surface of the target protein. Consequently, peptides derived from library screenings often modulate the target protein’s activity in vitro and in vivo and can be used as lead compounds in drug design and as alternatives to antibodies for target validation in both genomics and drug discovery. This review discusses the use of phage display to identify membrane receptor modulators with agonistic or antagonistic activities. Because isolating or producing recombinant membrane proteins for use as target molecules in library screening is often impossible, innovative selection strategies such as panning against whole cells or tissues, recombinant receptor ectodomains, or neutralizing antibodies to endogenous binding partners were devised. Prominent examples from a two-decade history of peptide phage display will be presented, focusing on the design of affinity selection experiments, methods for improving the initial hits, and applications of the identified peptides.

    10. Targeted skipping of human dystrophin exons in transgenic mouse model systemically for antisense drug development.

      Directory of Open Access Journals (Sweden)

      Bo Wu

      Full Text Available Antisense therapy has recently been demonstrated with great potential for targeted exon skipping and restoration of dystrophin production in cultured muscle cells and in muscles of Duchenne Muscular Dystrophy (DMD patients. Therapeutic values of exon skipping critically depend on efficacy of the drugs, antisense oligomers (AOs. However, no animal model has been established to test AO targeting human dystrophin exon in vivo systemically. In this study, we applied Vivo-Morpholino to the hDMD mouse, a transgenic model carrying the full-length human dystrophin gene, and achieved for the first time more than 70% efficiency of targeted human dystrophin exon skipping in vivo systemically. We also established a GFP-reporter myoblast culture to screen AOs targeting human dystrophin exon 50. Antisense efficiency for most AOs is consistent between the reporter cells, human myoblasts and in the hDMD mice in vivo. However, variation in efficiency was also clearly observed. A combination of in vitro cell culture and a Vivo-Morpholino based evaluation in vivo systemically in the hDMD mice therefore may represent a prudent approach for selecting AO drug and to meet the regulatory requirement.

    11. Herbal and polymeric approaches for liver-targeting drug delivery: novel strategies and their significance.

      Science.gov (United States)

      Rohilla, Raman; Garg, Tarun; Goyal, Amit K; Rath, Goutam

      2016-06-01

      The liver is a vital organ present in vertebrates, which performs many functions including detoxification, protein synthesis and production of various bio-chemicals which are very important for digestion. A large number of serious liver disorders affect millions of people worldwide which are very difficult to treat properly despite many efforts. There are several factors which are responsible for liver injuries, include plants (Crotalaria Senecio Heliotropium Symphytum officinale), drugs (analgesic and antibiotics), industrial toxins (mercury and lead), water, alcohol and so on. Herbal medicinal preparations can be used for the treatment of a large number of human liver disorders like cirrhosis, hepatitis, carcinomas, etc. Indian Medicinal Practitioner's Co-operative pharmacy and Stores (IMPCPS) approved herbal-based systems (Unani, Siddha and Ayurveda) for the treatment of various chronic liver disorders. Different types of the receptors are found on the surface of hepatocytes, Kupffer cell, hepatic stellate cell and sinusoidal endothelial cells, etc., which can be used for achieving liver targeting. These receptors bind to different types of ligands (galactosylated, lactobionic acid, asialofetuin, etc.) which can be used in the formulation to achieve targeted delivery of the drug. Various novel particulate approaches (liposomes, niosomes, nanoparticles, micelles, nanosuspensions, etc.) can be used to enhance the targeting efficiency of systems to receptors found on the surface of different cells present in the liver. In this review, we focused on the status of liver targeting via herbal and nanotechnology inspired formulation approaches. PMID:25101832

    12. DNA Gyrase Is the Target for the Quinolone Drug Ciprofloxacin in Arabidopsis thaliana*

      Science.gov (United States)

      Evans-Roberts, Katherine M.; Mitchenall, Lesley A.; Wall, Melisa K.; Leroux, Julie; Mylne, Joshua S.; Maxwell, Anthony

      2016-01-01

      The Arabidopsis thaliana genome contains four genes that were originally annotated as potentially encoding DNA gyrase: ATGYRA, ATGYRB1, ATGYRB2, and ATGYRB3. Although we subsequently showed that ATGYRB3 does not encode a gyrase subunit, the other three genes potentially encode subunits of a plant gyrase. We also showed evidence for the existence of supercoiling activity in A. thaliana and that the plant is sensitive to quinolone and aminocoumarin antibiotics, compounds that target DNA gyrase in bacteria. However, it was not possible at that time to show whether the A. thaliana genes encoded an active gyrase enzyme, nor whether that enzyme is indeed the target for the quinolone and aminocoumarin antibiotics. Here we show that an A. thaliana mutant resistant to the quinolone drug ciprofloxacin has a point mutation in ATGYRA. Moreover we show that, as in bacteria, the quinolone-sensitive (wild-type) allele is dominant to the resistant gene. Further we have heterologously expressed ATGYRA and ATGYRB2 in a baculovirus expression system and shown supercoiling activity of the partially purified enzyme. Expression/purification of the quinolone-resistant A. thaliana gyrase yields active enzyme that is resistant to ciprofloxacin. Taken together these experiments now show unequivocally that A. thaliana encodes an organelle-targeted DNA gyrase that is the target of the quinolone drug ciprofloxacin; this has important consequences for plant physiology and the development of herbicides. PMID:26663076

    13. Potential of targeted drug delivery system for the treatment of bone metastasis.

      Science.gov (United States)

      Vinay, Raichur; KusumDevi, V

      2016-01-01

      Bone metastasis is a devastating complication of cancer that requires an immediate attention. Although our understanding of the metastatic process has improved over the years, yet a number of questions still remain unanswered, and more research is required for complete understanding of the skeletal consequences of metastasis. Furthermore, as no effective treatments are available for some of the most common skeleton disorders such as arthritis, osteoarthritis, osteosarcoma and metastatic bone cancer, there is an urgent need to develop new drugs and drug delivery systems for safe and efficient clinical treatments. Hence this article describes the potential of targeted delivery platforms aimed specifically at bone metastasized tumors. The review gives a brief understanding of the proposed mechanisms of metastasis and focuses primarily on the targeting moieties such as bisphosphonates, which represent the current gold standard in bone metastasis therapies. Special focus has been given to the targeted nanoparticulate systems for treating bone metastasis and its future. Also highlighted are some of the therapeutic targets that can be exploited for designing therapies for bone metastasis. Some of the patented molecules for bone metastasis prevention and treatment have also been discussed. Recently proposed HIFU-CHEM, which utilizes High Intensity Focused ultrasound (HIFU) guided by MRI in combination with temperature-sensitive nanomedicines has also been briefed. The study has been concluded with a focus on the innovations requiring an immediate attention that could improve the treatment modality of bone metastasis.

    14. Prioritizing drug targets in Clostridium botulinum with a computational systems biology approach.

      Science.gov (United States)

      Muhammad, Syed Aun; Ahmed, Safia; Ali, Amjad; Huang, Hui; Wu, Xiaogang; Yang, X Frank; Naz, Anam; Chen, Jake

      2014-07-01

      A computational and in silico system level framework was developed to identify and prioritize the antibacterial drug targets in Clostridium botulinum (Clb), the causative agent of flaccid paralysis in humans that can be fatal in 5 to 10% of cases. This disease is difficult to control due to the emergence of drug-resistant pathogenic strains and the only available treatment antitoxin which can target the neurotoxin at the extracellular level and cannot reverse the paralysis. This study framework is based on comprehensive systems-scale analysis of genomic sequence homology and phylogenetic relationships among Clostridium, other infectious bacteria, host and human gut flora. First, the entire 2628-annotated genes of this bacterial genome were categorized into essential, non-essential and virulence genes. The results obtained showed that 39% of essential proteins that functionally interact with virulence proteins were identified, which could be a key to new interventions that may kill the bacteria and minimize the host damage caused by the virulence factors. Second, a comprehensive comparative COGs and blast sequence analysis of these proteins and host proteins to minimize the risks of side effects was carried out. This revealed that 47% of a set of C. botulinum proteins were evolutionary related with Homo sapiens proteins to sort out the non-human homologs. Third, orthology analysis with other infectious bacteria to assess broad-spectrum effects was executed and COGs were mostly found in Clostridia, Bacilli (Firmicutes), and in alpha and beta Proteobacteria. Fourth, a comparative phylogenetic analysis was performed with human microbiota to filter out drug targets that may also affect human gut flora. This reduced the list of candidate proteins down to 131. Finally, the role of these putative drug targets in clostridial biological pathways was studied while subcellular localization of these candidate proteins in bacterial cellular system exhibited that 68% of the

    15. Drugs targeting 5-hydroxytryptamine receptors in acute treatments of migraine attacks. A review of new drugs and new administration forms of established drugs

      DEFF Research Database (Denmark)

      Tfelt-Hansen, Peer C; Pihl, Thomas Peter Boye; Hougaard, Anders;

      2014-01-01

      Introduction: The development of sumatriptan, more than 20 years ago, added substantially to the characterization of 5-hydroxytryptamine (5-HT) receptors and their relevance to acute migraine therapy. Recently, 5-HT1F receptor agonists, with no vascular effects, have shown efficacy in the treatment...... of migraines. Areas covered: This evaluation reviews the recent advances in acute migraine therapy targeting the 5-HT receptor. Specifically, the authors review the pharmacokinetics, pharmacodynamics, clinical efficacy and safety of 5-HT1F receptor agonists and new formulations of sumatriptan...... in a low incidence of recurrence. None of these reviewed treatments are likely to fulfill patients' expectations, and the advancement of acute migraine drugs should likely depend on different mechanisms from current 5-HT-related drugs....

    16. Facile synthesis of manganese ferrite/graphene oxide nanocomposites for controlled targeted drug delivery

      Science.gov (United States)

      Wang, Guangshuo; Ma, Yingying; Zhang, Lina; Mu, Jingbo; Zhang, Zhixiao; Zhang, Xiaoliang; Che, Hongwei; Bai, Yongmei; Hou, Junxian

      2016-03-01

      In this study, manganese ferrite/graphene oxide (MnFe2O4/GO) nanocomposites as controlled targeted drug delivery were prepared by a facile sonochemical method. It was found that GO nanosheets were fully exfoliated and decorated with MnFe2O4 nanoparticles having diameters of 5-13 nm. The field-dependent magnetization curve indicated superparamagnetic behavior of the obtained MnFe2O4/GO with saturation magnetization of 34.9 emu/g at room temperature. The in vitro cytotoxicity testing exhibited negligible cytotoxicity of as-prepared MnFe2O4/GO even at the concentration as high as 150 μg/mL. Doxorubicin hydrochloride (DOX) as an anti-tumor model drug was utilized to explore the application potential of MnFe2O4/GO for controlled drug delivery. The drug loading capacity of this nanocarrier was as high as 0.97 mg/mg and the drug release behavior showed a sustained and pH-responsive way.

    17. Development of high drug-loading nanomicelles targeting steroids to the brain

      Directory of Open Access Journals (Sweden)

      Zheng S

      2013-12-01

      Full Text Available Sijia Zheng,1,* Yanqi Xie,1,* Yuan Li,1 Ling Li,1 Ning Tian,1 Wenbo Zhu,2 Guangmei Yan,2 Chuanbin Wu,1 Haiyan Hu1 1School of Pharmaceutical Sciences, 2Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, People's Republic of China *These authors contributed equally to this workAbstract: The objective of this research was to develop and evaluate high drug-loading ligand-modified nanomicelles to deliver a steroidal compound to the brain. YC1 (5α-cholestane-24-methylene-3β, 5α, 6β, 19-tetraol, with poor solubility and limited access to the brain, for the first time, has been proved to be an effective neuroprotective steroid by our previous studies. Based on the principle of ‘like dissolves like’, cholesterol, which shares the same steroidal parent nucleus with YC1, was selected to react with sodium alginate, producing amphiphilic sodium alginate–cholesterol derivatives (SACDs. To increase the grafting ratio and drug loading, cholesterol was converted to cholesteryl chloroformate, for the first time, before reacting with sodium alginate. Further, lactoferrin was conjugated on SACDs to provide lactoferrin-SACDs (Lf-SACD, which was established by immune electron microscopy (IEM and self-assembled into brain-targeting nanomicelles. These nanomicelles were negatively charged and spherical in nature, with an average size of <200 nm. The YC1 drug loading was increased due to the cholesteryl inner cores of the nanomicelles, and the higher the grafting ratio was, the lower the critical micelle concentration (CMC value of SACD, and the higher drug loading. The in vitro drug release, studied by bulk-equilibrium dialysis in 20 mL of 6% hydroxypropyl-β-cyclodextrin solution at 37°C, indicated a prolonged release profile. The YC1 concentration in mouse brain delivered by lactoferrin-modified nanomicelles was higher than in those delivered by non-modified nanomicelles and YC1 solution. The unique brain-targeting

    18. HER2 Targeting Peptides Screening and Applications in Tumor Imaging and Drug Delivery

      Science.gov (United States)

      Geng, Lingling; Wang, Zihua; Jia, Xiangqian; Han, Qiuju; Xiang, Zhichu; Li, Dan; Yang, Xiaoliang; Zhang, Di; Bu, Xiangli; Wang, Weizhi; Hu, Zhiyuan; Fang, Qiaojun

      2016-01-01

      Herein, computational-aided one-bead-one-compound (OBOC) peptide library design combined with in situ single-bead sequencing microarray methods were successfully applied in screening peptides targeting at human epidermal growth factor receptor-2 (HER2), a biomarker of human breast cancer. As a result, 72 novel peptides clustered into three sequence motifs which are PYL***NP, YYL***NP and PPL***NP were acquired. Particularly one of the peptides, P51, has nanomolar affinity and high specificity for HER2 in ex vivo and in vivo tests. Moreover, doxorubicin (DOX)-loaded liposome nanoparticles were modified with peptide P51 or P25 and demonstrated to improve the targeted delivery against HER2 positive cells. Our study provides an efficient peptide screening method with a combination of techniques and the novel screened peptides with a clear binding site on HER2 can be used as probes for tumor imaging and targeted drug delivery. PMID:27279916

    19. Orphan G protein-coupled receptors (GPCRs):biological functions and potential drug targets

      Institute of Scientific and Technical Information of China (English)

      Xiao-long TANG; Ying WANG; Da-li LI; Jian LUO; Ming-yao LIU

      2012-01-01

      The superfamily of G protein-coupled receptors (GPCRs) includes at least 800 seven-transmembrane receptors that participate in diverse physiological and pathological functions.GPCRs are the most successful targets of modern medicine,and approximately 36%of marketed pharmaceuticals target human GPCRs.However,the endogenous ligands of more than 140 GPCRs remain unidentified,leaving the natural functions of those GPCRs in doubt.These are the so-called orphan GPCRs,a great source of drug targets.This review focuses on the signaling transduction pathways of the Adhesion GPCR family,the LGR subfamily,and the PSGR subfamily,and their potential functions in immunology,development,and cancers.In this review,we present the current approaches and difficulties of orphan GPCR deorphanization and characterization.

    20. Metabolic network analysis-based identification of antimicrobial drug targets in category A bioterrorism agents.

      Science.gov (United States)

      Ahn, Yong-Yeol; Lee, Deok-Sun; Burd, Henry; Blank, William; Kapatral, Vinayak

      2014-01-01

      The 2001 anthrax mail attacks in the United States demonstrated the potential threat of bioterrorism, hence driving the need to develop sophisticated treatment and diagnostic protocols to counter biological warfare. Here, by performing flux balance analyses on the fully-annotated metabolic networks of multiple, whole genome-sequenced bacterial strains, we have identified a large number of metabolic enzymes as potential drug targets for each of the three Category A-designated bioterrorism agents including Bacillus anthracis, Francisella tularensis and Yersinia pestis. Nine metabolic enzymes- belonging to the coenzyme A, folate, phosphatidyl-ethanolamine and nucleic acid pathways common to all strains across the three distinct genera were identified as targets. Antimicrobial agents against some of these enzymes are available. Thus, a combination of cross species-specific antibiotics and common antimicrobials against shared targets may represent a useful combinatorial therapeutic approach against all Category A bioterrorism agents.

    1. Metabolic network analysis-based identification of antimicrobial drug targets in category A bioterrorism agents.

      Directory of Open Access Journals (Sweden)

      Yong-Yeol Ahn

      Full Text Available The 2001 anthrax mail attacks in the United States demonstrated the potential threat of bioterrorism, hence driving the need to develop sophisticated treatment and diagnostic protocols to counter biological warfare. Here, by performing flux balance analyses on the fully-annotated metabolic networks of multiple, whole genome-sequenced bacterial strains, we have identified a large number of metabolic enzymes as potential drug targets for each of the three Category A-designated bioterrorism agents including Bacillus anthracis, Francisella tularensis and Yersinia pestis. Nine metabolic enzymes- belonging to the coenzyme A, folate, phosphatidyl-ethanolamine and nucleic acid pathways common to all strains across the three distinct genera were identified as targets. Antimicrobial agents against some of these enzymes are available. Thus, a combination of cross species-specific antibiotics and common antimicrobials against shared targets may represent a useful combinatorial therapeutic approach against all Category A bioterrorism agents.

    2. Trypanothione Reductase: A Viable Chemotherapeutic Target for Antitrypanosomal and Antileishmanial Drug Design

      Directory of Open Access Journals (Sweden)

      M. Omar F. Khan

      2007-01-01

      Full Text Available Trypanosomiasis and leishmaniasis are two debilitating disease groups caused by parasites of Trypanosoma and Leishmania spp. and affecting millions of people worldwide. A brief outline of the potential targets for rational drug design against these diseases are presented, with an emphasis placed on the enzyme trypanothione reductase. Trypanothione reductase was identified as unique to parasites and proposed to be an effective target against trypanosomiasis and leishmaniasis. The biochemical basis of selecting this enzyme as a target, with reference to the simile and contrast to human analogous enzyme glutathione reductase, and the structural aspects of its active site are presented. The process of designing selective inhibitors for the enzyme trypanothione reductase has been discussed. An overview of the different chemical classes of inhibitors of trypanothione reductase with their inhibitory activities against the parasites and their prospects as future chemotherapeutic agents are briefl y revealed.

    3. Multi-ligand nanoparticles for targeted drug delivery to the injured vascular wall

      Science.gov (United States)

      Kona, Soujanya

      Pathological conditions like coronary artery disease, acute myocardial infarction, stroke, and peripheral artery diseases as well as cardiovascular interventions used in the treatment of coronary artery diseases such as angioplasty and stenting damage/injure the blood vessel wall, leading to inflamed or activated endothelial cells that have been implicated in events leading to thrombosis, inflammation, and restenosis. Oral administration of anti-coagulant and anti-inflammatory drugs causes systemic toxicity, bleeding, patient incompliance, and inadequate amounts of drugs at the injured area. Though drug-eluting stents have shown therapeutic benefits, complications such as in-stent restenosis and late thrombosis still remain and are a cause for concern. Rapid growth in the field of nanotechnology and nanoscience in recent years has paved the way for new targeted and controlled drug delivery strategies. In this perspective, the development of biodegradable nanoparticles for targeted intracellular drug delivery to the inflamed endothelial cells may offer an improved avenue for treatment of cardiovascular diseases. The major objective of this research was to develop "novel multi-ligand nanoparticles," as drug carriers that can efficiently target and deliver therapeutic agents to the injured/inflamed vascular cells under dynamic flow conditions. Our approach mimics the natural binding ability of platelets to injured/activated endothelial cells through glycoprotein Ib (GPIb) bound to P-selectin expressed on inflamed endothelial cells and to the subendothelium through GPIb binding to von Willebrand factor (vWF) deposited onto the injured vascular wall. Our design also exploits the natural cell membrane translocation ability of the internalizing cell peptide - trans-activating transcriptor (TAT) to enhance the nanoparticle uptake by the targeted cells. Our hypothesis is that these multi-ligand nanoparticles would show an increased accumulation at the injury site since GPIb

    4. Controlled drug release from lung-targeted nanocarriers via chemically mediated shell permeabilisation.

      Science.gov (United States)

      Chen, Hanpeng; Woods, Arcadia; Forbes, Ben; Jones, Stuart

      2016-09-25

      Nanocarriers can aid therapeutic agent administration to the lung, but controlling drug delivery from these systems after deposition in the airways can be problematic. The aim of this study was to evaluate if chemically mediated shell permeabilisation could help manipulate the rate and extent of nanocarrier drug release. Rifampicin was loaded into lipid shell (loading efficiency 41.0±11.4%, size 50nm) and polymer shell nanocarriers (loading efficiency 25.9±2.3%, size 250nm). The drug release at pH 7.4 (lung epithelial pH) and 4.2 (macrophage endosomal pH) with and without the chemical permeabilisers (Pluronic L62D - lipid nanocarriers; H(+)- polymer nanocarriers) was then tested. At pH 7.4 the presence of the permeabilisers increased nanocarrier drug release rate (from 3.2μg/h to 6.8μg/h for lipid shell nanocarriers, 2.3μg/h to 3.4μg/h for polymer shell nanocarriers) and drug release extent (from 50% to 80% for lipid shell nanocarriers, from 45% to 76% for polymer shell nanocarriers). These effects were accompanied by lipid nanocarrier distension (from 50 to 240nm) and polymer shell hydrolysis. At pH 4.2 the polymer nanocarriers did not respond to the permeabiliser, but the lipid nanocarrier maintained a robust drug release enhancement response and hence they demonstrated that the manipulation of controlled drug release from lung-targeted nanocarriers was possible through chemically mediated shell permeabilisation.

    5. Comparison of FDA Approved Kinase Targets to Clinical Trial Ones: Insights from Their System Profiles and Drug-Target Interaction Networks

      Directory of Open Access Journals (Sweden)

      Jingyu Xu

      2016-01-01

      Full Text Available Kinase is one of the most productive classes of established targets, but the majority of approved drugs against kinase were developed only for cancer. Intensive efforts were therefore exerted for releasing its therapeutic potential by discovering new therapeutic area. Kinases in clinical trial could provide great opportunities for treating various diseases. However, no systematic comparison between system profiles of established targets and those of clinical trial ones was conducted. The reveal of probable difference or shift of trend would help to identify key factors defining druggability of established targets. In this study, a comparative analysis of system profiles of both types of targets was conducted. Consequently, the systems profiles of the majority of clinical trial kinases were identified to be very similar to those of established ones, but percentages of established targets obeying the system profiles appeared to be slightly but consistently higher than those of clinical trial targets. Moreover, a shift of trend in the system profiles from the clinical trial to the established targets was identified, and popular kinase targets were discovered. In sum, this comparative study may help to facilitate the identification of the druggability of established drug targets by their system profiles and drug-target interaction networks.

    6. Perspective of microsomal prostaglandin E2 synthase-1 as drug target in inflammation-related disorders.

      Science.gov (United States)

      Koeberle, Andreas; Werz, Oliver

      2015-11-01

      Prostaglandin (PG)E2 encompasses crucial roles in pain, fever, inflammation and diseases with inflammatory component, such as cancer, but is also essential for gastric, renal, cardiovascular and immune homeostasis. Cyclooxygenases (COX) convert arachidonic acid to the intermediate PGH2 which is isomerized to PGE2 by at least three different PGE2 synthases. Inhibitors of COX - non-steroidal anti-inflammatory drugs (NSAIDs) - are currently the only available therapeutics that target PGE2 biosynthesis. Due to adverse effects of COX inhibitors on the cardiovascular system (COX-2-selective), stomach and kidney (COX-1/2-unselective), novel pharmacological strategies are in demand. The inducible microsomal PGE2 synthase (mPGES)-1 is considered mainly responsible for the excessive PGE2 synthesis during inflammation and was suggested as promising drug target for suppressing PGE2 biosynthesis. However, 15 years after intensive research on the biology and pharmacology of mPGES-1, the therapeutic value of mPGES-1 as drug target is still vague and mPGES-1 inhibitors did not enter the market so far. This commentary will first shed light on the structure, mechanism and regulation of mPGES-1 and will then discuss its biological function and the consequence of its inhibition for the dynamic network of eicosanoids. Moreover, we (i) present current strategies for interfering with mPGES-1-mediated PGE2 synthesis, (ii) summarize bioanalytical approaches for mPGES-1 drug discovery and (iii) describe preclinical test systems for the characterization of mPGES-1 inhibitors. The pharmacological potential of selective mPGES-1 inhibitor classes as well as dual mPGES-1/5-lipoxygenase inhibitors is reviewed and pitfalls in their development, including species discrepancies and loss of in vivo activity, are discussed.

    7. MDA Program against lymphatic filariasis: Are we on the path to success? Experience from Uttara Kannada District, Karnataka

      OpenAIRE

      Praveen Kulkarni; Ravi Kumar; Ravi Marinayakanakoppalu Rajegowda; Harshith Gowdra Channabasappa; NC Ashok

      2014-01-01

      Context: Lymphatic filariasis or elephantiasis a serious public health problem in India. Millennium Development Goals and National Health Policies purport to eliminate filariasis by 2015. The concept of mass drug administration (MDA) is to approach every individual in the target community and administer annual single dose of anti-filarial drugs (DEC or DEC+Albendazole). Aims: 1. Assess the coverage and compliance to MDA in the district. 2. Assess the awareness of elephantiasis among beneficia...

    8. Folate-conjugated boron nitride nanospheres for targeted delivery of anticancer drug

      Directory of Open Access Journals (Sweden)

      Feng S

      2016-09-01

      Full Text Available Shini Feng,1 Huijie Zhang,1 Ting Yan,1 Dandi Huang,1 Chunyi Zhi,2 Hideki Nakanishi,1 Xiao-Dong Gao1 1Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China; 2Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, People’s Republic of China Abstract: With its unique physical and chemical properties and structural similarity to carbon, boron nitride (BN has attracted considerable attention and found many applications. Biomedical applications of BN have recently started to emerge, raising great hopes in drug and gene delivery. Here, we developed a targeted anticancer drug delivery system based on folate-conjugated BN nanospheres (BNNS with receptor-mediated targeting. Folic acid (FA was successfully grafted onto BNNS via esterification reaction. In vitro cytotoxicity assay showed that BNNS-FA complexes were non-toxic to HeLa cells up to a concentration of 100 µg/mL. Then, doxorubicin hydrochloride (DOX, a commonly used anticancer drug, was loaded onto BNNS-FA complexes. BNNS-FA/DOX complexes were stable at pH 7.4 but effectively released DOX at pH 5.0, which exhibited a pH sensitive and sustained release pattern. BNNS-FA/DOX complexes could be recognized and specifically internalized by HeLa cells via FA receptor-mediated endocytosis. BNNS-FA/DOX complexes exhibited greater cytotoxicity to HeLa cells than free DOX and BNNS/DOX complexes due to the increased cellular uptake of DOX mediated by the FA receptor. Therefore, BNNS-FA complexes had strong potential for targeted cancer therapy. Keywords: boron nitride nanospheres, folic acid, doxorubicin, targeted delivery, cancer therapy

    9. Development of high drug-loading nanomicelles targeting steroids to the brain.

      Science.gov (United States)

      Zheng, Sijia; Xie, Yanqi; Li, Yuan; Li, Ling; Tian, Ning; Zhu, Wenbo; Yan, Guangmei; Wu, Chuanbin; Hu, Haiyan

      2014-01-01

      The objective of this research was to develop and evaluate high drug-loading ligand-modified nanomicelles to deliver a steroidal compound to the brain. YC1 (5α-cholestane-24-methylene-3β, 5α, 6β, 19-tetraol), with poor solubility and limited access to the brain, for the first time, has been proved to be an effective neuroprotective steroid by our previous studies. Based on the principle of 'like dissolves like', cholesterol, which shares the same steroidal parent nucleus with YC1, was selected to react with sodium alginate, producing amphiphilic sodium alginate- cholesterol derivatives (SACDs). To increase the grafting ratio and drug loading, cholesterol was converted to cholesteryl chloroformate, for the first time, before reacting with sodium alginate. Further, lactoferrin was conjugated on SACDs to provide lactoferrin-SACDs (Lf-SACD), which was established by immune electron microscopy (IEM) and self-assembled into brain-targeting nanomicelles. These nanomicelles were negatively charged and spherical in nature, with an average size of cyclodextrin solution at 37°C, indicated a prolonged release profile. The YC1 concentration in mouse brain delivered by lactoferrin-modified nanomicelles was higher than in those delivered by non-modified nanomicelles and YC1 solution. The unique brain-targeting nanomicelle system may provide a promising carrier to deliver hydrophobic drugs across the blood-brain barrier for the treatment of brain diseases. PMID:24379663

    10. Caleosin-based nanoscale oil bodies for targeted delivery of hydrophobic anticancer drugs

      International Nuclear Information System (INIS)

      Nanoscale artificial oil bodies (NOBs) could be assembled from plant oil, phospholipids (PLs), and oleosin (Ole) as previously reported. NOBs have a lipid-based structure that contains a central oil space enclosed by a monolayer of Ole-bound PLs. As an oil structural protein, Ole functions to maintain the integrity of NOBs. Like Ole, caleosin (Cal) is a plant oil-associated protein. In this study, we investigated the feasibility of NOBs assembled by Cal for targeted delivery of drugs. Cal was first fused with anti-HER2/neu affibody (ZH2), and the resulting fusion gene (Cal–ZH2) was then expressed in Escherichia coli. Consequently, NOBs assembled with the fusion protein were selectively internalized by HER2/neu-positive tumor cells. The internalization efficiency could reach as high as 90%. Furthermore, a hydrophobic anticancer drug, Camptothecin (CPT), was encapsulated into Cal-based NOBs. These CPT-loaded NOBs had a size around 200 nm and were resistant to hemolysis. Release of CPT from NOBs at the non-permissive condition followed a sustained and prolonged profile. After administration of the CPT formulation, Cal–ZH2-displayed NOBs exhibited a strong antitumor activity toward HER2/neu-positive cells both in vitro and in vivo. The result indicates the potential of Cal-based NOBs for targeted delivery of hydrophobic drugs.

    11. Inulin-based polymer coated SPIONs as potential drug delivery systems for targeted cancer therapy.

      Science.gov (United States)

      Scialabba, C; Licciardi, M; Mauro, N; Rocco, F; Ceruti, M; Giammona, G

      2014-11-01

      This paper deal with the synthesis and characterization of PEGylated squalene-grafted-inulin amphiphile capable of self-assembling and self-organizing into nanocarriers once placed in aqueous media. It was exploited as coating agent for obtaining doxorubicin loaded superparamagnetic iron oxide nanoparticles (SPIONs) endowed with stealth like behavior and excellent physicochemical stability. Inulin was firstly modified in the side chain with primary amine groups, followed in turn by conjugation with squalenoyl derivatives through common amidic coupling agents and PEGylation by imine linkage. Polymer coated SPIONs were so obtained by spontaneous self-assembling of inulin copolymer onto magnetite surface involving hydrophobic-hydrophobic interactions between the metallic core and the squalene moieties. The system was characterized in terms of hydrodynamic radius, zeta potential, shape and drug loading capacity. On the whole, the stealth-like shell stabilized the suspension in aqueous media, though allowing the release of the doxorubicin loaded in therapeutic range. The cytotoxicity profile on cancer (HCT116) cell line and in vitro drug uptake were evaluated both with and without an external magnetic field used as targeting agent and uptake promoter, displaying that magnetic targeting implies advantageous therapeutic effects, that is amplified drug uptake and increased anticancer activity throughout the tumor mass.

    12. The periplasmic protein TolB as a potential drug target in Pseudomonas aeruginosa.

      Directory of Open Access Journals (Sweden)

      Alessandra Lo Sciuto

      Full Text Available The Gram-negative bacterium Pseudomonas aeruginosa is one of the most dreaded pathogens in the hospital setting, and represents a prototype of multi-drug resistant "superbug" for which effective therapeutic options are very limited. The identification and characterization of new cellular functions that are essential for P. aeruginosa viability and/or virulence could drive the development of anti-Pseudomonas compounds with novel mechanisms of action. In this study we investigated whether TolB, the periplasmic component of the Tol-Pal trans-envelope protein complex of Gram-negative bacteria, represents a potential drug target in P. aeruginosa. By combining conditional mutagenesis with the analysis of specific pathogenicity-related phenotypes, we demonstrated that TolB is essential for P. aeruginosa growth, both in laboratory and clinical strains, and that TolB-depleted P. aeruginosa cells are strongly defective in cell-envelope integrity, resistance to human serum and several antibiotics, as well as in the ability to cause infection and persist in an insect model of P. aeruginosa infection. The essentiality of TolB for P. aeruginosa growth, resistance and pathogenicity highlights the potential of TolB as a novel molecular target for anti-P. aeruginosa drug discovery.

    13. The periplasmic protein TolB as a potential drug target in Pseudomonas aeruginosa.

      Science.gov (United States)

      Lo Sciuto, Alessandra; Fernández-Piñar, Regina; Bertuccini, Lucia; Iosi, Francesca; Superti, Fabiana; Imperi, Francesco

      2014-01-01

      The Gram-negative bacterium Pseudomonas aeruginosa is one of the most dreaded pathogens in the hospital setting, and represents a prototype of multi-drug resistant "superbug" for which effective therapeutic options are very limited. The identification and characterization of new cellular functions that are essential for P. aeruginosa viability and/or virulence could drive the development of anti-Pseudomonas compounds with novel mechanisms of action. In this study we investigated whether TolB, the periplasmic component of the Tol-Pal trans-envelope protein complex of Gram-negative bacteria, represents a potential drug target in P. aeruginosa. By combining conditional mutagenesis with the analysis of specific pathogenicity-related phenotypes, we demonstrated that TolB is essential for P. aeruginosa growth, both in laboratory and clinical strains, and that TolB-depleted P. aeruginosa cells are strongly defective in cell-envelope integrity, resistance to human serum and several antibiotics, as well as in the ability to cause infection and persist in an insect model of P. aeruginosa infection. The essentiality of TolB for P. aeruginosa growth, resistance and pathogenicity highlights the potential of TolB as a novel molecular target for anti-P. aeruginosa drug discovery. PMID:25093328

    14. Tumor-Targeting Co-Delivery of Drug and Gene from Temperature-Triggered Micelles.

      Science.gov (United States)

      Seo, Seog-Jin; Lee, Seon-Young; Choi, Seong-Jun; Kim, Hae-Won

      2015-09-01

      Co-delivery strategy using multifunctional nanocarriers is an attractive option for the synergistic and enhanced effects in cancer treatment, but one system integrating multiple functions for controlled release at the target is still challenging. Herein, this study shows the synthesis and characterization of our stimulus-responsive co-delivery system for the controlled release into tumors, which is composed of polyethylenimine (PEI)-linked Pluronic F127 (PF127) and folic acid (FA), called PF127-PEI-FA. PF127-PEI-FA system facilitated drug loading and gene complex formation, and showed controlled release behaviors in response to hitting temperature to hyperthermia. PF127-PEI-FA system was demonstrated to be biocompatible and showed receptor-mediated gene delivery. The results of our multifunctional nanocarrier system that enabled co-delivery suggest a promising potential for controlled drug release at targeted areas. However, further in-depth studies on the use of therapeutic drugs and genes in multiple cell types and the animal response are required. PMID:25990042

    15. Goblet cell targeting nanoparticle containing drug-loaded micelle cores for oral delivery of insulin.

      Science.gov (United States)

      Zhang, Peiwen; Xu, Yining; Zhu, Xi; Huang, Yuan

      2015-12-30

      Oral administration of insulin remains a challenge due to its poor enzymatic stability and inefficient permeation across epithelium. We herein developed a novel self-assembled polyelectrolyte complex nanoparticles by coating insulin-loaded dodecylamine-graft-γ-polyglutamic acid micelles with trimethyl chitosan (TMC). The TMC material was also conjugated with a goblet cell-targeting peptide to enhance the affinity of nanoparticles with epithelium. The developed nanoparticle possessed significantly enhanced colloid stability, drug protection ability and ameliorated drug release profile compared with graft copolymer micelles or ionic crosslinked TMC nanoparticles. For in vitro evaluation, Caco-2/HT29-MTX-E12 cell co-cultures, which composed of not only enterocyte-like cells but also mucus-secreting cells and secreted mucus layer, were applied to mimic the epithelium. Intracellular uptake and transcellular permeation of encapsulated drug were greatly enhanced for NPs as compared with free insulin or micelles. Goblet cell-targeting modification further increased the affinity of NPs with epithelium with changed cellular internalization mechanism. The influence of mucus on the cell uptake was also investigated. Ex vivo performed with rat mucosal tissue demonstrated that the nanoparticle could facilitate the permeation of encapsulated insulin across the intestinal epithelium. In vivo study preformed on diabetic rats showed that the orally administered nanoparticles elicited a prolonged hypoglycemic response with relative bioavailability of 7.05%.

    16. Bacillus-shape design of polymer based drug delivery systems with janus-faced function for synergistic targeted drug delivery and more effective cancer therapy.

      Science.gov (United States)

      Cui, Fei; Lin, Jinyan; Li, Yang; Li, Yanxiu; Wu, Hongjie; Yu, Fei; Jia, Mengmeng; Yang, Xiangrui; Wu, Shichao; Xie, Liya; Ye, Shefang; Luo, Fanghong; Hou, Zhenqing

      2015-04-01

      The particle shape of the drug delivery systems had a strong impact on their in vitro and in vivo performance, but there was limited availability of techniques to produce the specific shaped drug carriers. In this article, the novel methotrexate (MTX) decorated MPEG-PLA nanobacillus (MPEG-PLA-MTX NB) was prepared by the self-assembly technique followed by the extrusion through SPG membrane with high N2 pressure for targeted drug delivery, in which Janus-like MTX was not only used as a specific anticancer drug but could also be served as a tumor-targeting ligand. The MPEG-PLA-MTX NBs demonstrated much higher in vitro and in vivo targeting efficiency compared to the MPEG-PLA-MTX nanospheres (MPEG-PLA-MTX NSs) and MPEG-PLA nanospheres (MPEG-PLA NSs). In addition, the MPEG-PLA-MTX NBs also displayed much more excellent in vitro and in vivo antitumor activity than the MPEG-PLA-MTX NSs and free MTX injection. To our knowledge, this work provided the first example of the integration of the shape design (which mediated an early phase tumor accumulation and a late-phase cell internalization) and Janus-faced function (which mediated an early phase active targeting effect and a late-phase anticancer effect) on the basis of nanoscaled drug delivery systems. The highly convergent and cooperative drug delivery strategy opens the door to more drug delivery systems with new shapes and functions for cancer therapy.

    17. Hsp90 is a direct target of the anti-allergic drugs disodium cromoglycate and amlexanox.

      Science.gov (United States)

      Okada, Miki; Itoh, Hideaki; Hatakeyama, Takashi; Tokumitsu, Hiroshi; Kobayashi, Ryoji

      2003-09-01

      Hsp90 (heat-shock protein 90) alone can act to prevent protein aggregation and promote refolding in vitro, but in vivo it operates as a part of a multichaperone complex, which includes Hsp70 and cohort proteins. Since the physiological function of Hsp90 is not yet fully understood, the development of specific antagonists might open new lines of investigation on the role of Hsp90. In an effort to discover Hsp90 antagonists, we screened many drugs and found that the anti-allergic drugs DSCG (disodium cromoglycate) and amlexanox target Hsp90. Both drugs were found to bind directly wild-type Hsp90 via the N- and C-terminal domains. Both drugs strongly suppressed the in vitro chaperone activity of native Hsp90 towards citrate synthase at 1.5-3.0 microM. Amlexanox suppressed C-terminal chaperone activity in vitro, but not N-terminal chaperone activity, and inhibited the association of cohort proteins, such as cyclophilin 40 and Hsp-organizing protein, to the C-terminal domain of Hsp90. These data suggest that amlexanox might disrupt the multichaperone complex, including Hsp70 and cohort proteins, both in vitro and in vivo. Although DSCG inhibited the in vitro chaperone activity of the N-terminal domain, the drug had no effect either on the C-terminal chaperone activity or on the association of the cohort proteins with the C-terminus of Hsp90. The physiological significance of these interactions in vivo remains to be investigated further, but undoubtedly must be taken into account when considering the pharmacology of anti-allergic drugs. DSCG and amlexanox may serve as useful tools for evaluating the physiological significance of Hsp90. PMID:12803546

    18. Fighting cancer with nanomedicine---drug-polyester nanoconjugates for targeted cancer therapy

      Science.gov (United States)

      Yin, Qian

      The aim of my Ph. D. research is to develop drug-polyester nanoconjugates (NCs) as a novel translational polymeric drug delivery system that can successfully evade non-specific uptake by reticuloendothelial system (RES) and facilitate targeted cancer diagnosis and therapy. By uniquely integrating well-established chemical reaction-controlled ring opening polymerization (ROP) with nanoprecipitation technique, I successfully developed a polymeric NC system based on poly(lactic acid) and poly(O-carboxyanhydrides) (OCA) that allows for the quantitative loading and controlled release of a variety of anticancer drugs. The developed NC system could be easily modified with parmidronate, one of bisphosphonates commonly used as the treatment for disease characterized by osteolysis, to selectively deliver doxorubicin (Doxo) to the bone tissues and substantially to improve their therapeutic efficiency in inhibiting the growth of osteosarcoma in both murine and canine models. More importantly, the developed NCs could avidly bind to human serum albumin, a ubiquitous protein in the blood, to bypass the endothelium barrier and penetrate into tumor tissues more deeply and efficiently. When compared with PEGylated NCs, these albumin-bound NCs showed significantly reduced accumulation in RES and enhanced tumor accumulation, which consequently contributed to higher their tumor inhibition capabilities. In addition, the developed NC system allows easy incorporation of X-ray computed tomography (CT) contrast agents to largely facilitate personalized therapy by improving diagnosis accuracy and monitoring therapeutic efficacy. Through the synthetic and formulation strategy I developed, a large quantity (grams or larger-scale) of drug-polyester NCs can be easily obtained, which can be used as a model drug delivery system for fundamental studies as well as a real drug delivery system for disease treatment in clinical settings.

    19. Development of multifunctional nanoparticles for targeted drug delivery and noninvasive imaging of therapeutic effect.

      Science.gov (United States)

      Sajja, Hari Krishna; East, Michael P; Mao, Hui; Wang, Y Andrew; Nie, Shuming; Yang, Lily

      2009-03-01

      Nanotechnology is a multidisciplinary scientific field undergoing explosive development. Nanometer-sized particles offer novel structural, optical and electronic properties that are not attainable with individual molecules or bulk solids. Advances in nanomedicine can be made by engineering biodegradable nanoparticles such as magnetic iron oxide nanoparticles, polymers, dendrimers and liposomes that are capable of targeted delivery of both imaging agents and anticancer drugs. This leads toward the concept and possibility of personalized medicine for the potential of early detection of cancer lesions, determination of molecular signatures of the tumor by noninvasive imaging and, most importantly, molecular targeted cancer therapy. Increasing evidence suggests that the nanoparticles, whose surface contains a targeting molecule that binds to receptors highly expressed in tumor cells, can serve as cancer image contrast agents to increase sensitivity and specificity in tumor detection. In comparison with other small molecule contrast agents, the advantage of using nanoparticles is their large surface area and the possibility of surface modifications for further conjugation or encapsulation of large amounts of therapeutic agents. Targeted nanoparticles ferry large doses of therapeutic agents into malignant cells while sparing the normal healthy cells. Such multifunctional nanodevices hold the promise of significant improvement of current clinical management of cancer patients. This review explores the development of nanoparticles for enabling and improving the targeted delivery of therapeutic agents, the potential of nanomedicine, and the development of novel and more effective diagnostic and screening techniques to extend the limits of molecular diagnostics providing point-of-care diagnosis and more personalized medicine.

    20. Emerging Glycolysis Targeting and Drug Discovery from Chinese Medicine in Cancer Therapy

      Directory of Open Access Journals (Sweden)

      Zhiyu Wang

      2012-01-01

      Full Text Available Molecular-targeted therapy has been developed for cancer chemoprevention and treatment. Cancer cells have different metabolic properties from normal cells. Normal cells mostly rely upon the process of mitochondrial oxidative phosphorylation to produce energy whereas cancer cells have developed an altered metabolism that allows them to sustain higher proliferation rates. Cancer cells could predominantly produce energy by glycolysis even in the presence of oxygen. This alternative metabolic characteristic is known as the “Warburg Effect.” Although the exact mechanisms underlying the Warburg effect are unclear, recent progress indicates that glycolytic pathway of cancer cells could be a critical target for drug discovery. With a long history in cancer treatment, traditional Chinese medicine (TCM is recognized as a valuable source for seeking bioactive anticancer compounds. A great progress has been made to identify active compounds from herbal medicine targeting on glycolysis for cancer treatment. Herein, we provide an overall picture of the current understanding of the molecular targets in the cancer glycolytic pathway and reviewed active compounds from Chinese herbal medicine with the potentials to inhibit the metabolic targets for cancer treatment. Combination of TCM with conventional therapies will provide an attractive strategy for improving clinical outcome in cancer treatment.

    1. Identification of Potential Drug Targets in Cancer Signaling Pathways using Stochastic Logical Models.

      Science.gov (United States)

      Zhu, Peican; Aliabadi, Hamidreza Montazeri; Uludağ, Hasan; Han, Jie

      2016-03-18

      The investigation of vulnerable components in a signaling pathway can contribute to development of drug therapy addressing aberrations in that pathway. Here, an original signaling pathway is derived from the published literature on breast cancer models. New stochastic logical models are then developed to analyze the vulnerability of the components in multiple signalling sub-pathways involved in this signaling cascade. The computational results are consistent with the experimental results, where the selected proteins were silenced using specific siRNAs and the viability of the cells were analyzed 72 hours after silencing. The genes elF4E and NFkB are found to have nearly no effect on the relative cell viability and the genes JAK2, Stat3, S6K, JUN, FOS, Myc, and Mcl1 are effective candidates to influence the relative cell growth. The vulnerabilities of some targets such as Myc and S6K are found to vary significantly depending on the weights of the sub-pathways; this will be indicative of the chosen target to require customization for therapy. When these targets are utilized, the response of breast cancers from different patients will be highly variable because of the known heterogeneities in signaling pathways among the patients. The targets whose vulnerabilities are invariably high might be more universally acceptable targets.

    2. A smart multifunctional nanocomposite for intracellular targeted drug delivery and self-release

      Energy Technology Data Exchange (ETDEWEB)

      Wang Chan; Tao Shengyang; Hu Tao; Yang Jingbang; Meng Changgong [School of Chemical Engineering, Dalian University of Technology, Dalian, Liaoning (China); Lv Piping; Wei Wei, E-mail: taosy@dlut.edu.cn [National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing (China)

      2011-10-14

      A multifunctional 'all-in-one' nanocomposite is fabricated using a colloid, template and surface-modification method. This material encompasses magnetic induced target delivery, cell uptake promotion and controlled drug release in one system. The nanocomposite is characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, N{sub 2} adsorption and vibrating sample magnetometry. The prepared material has a diameter of 350-400 nm, a high surface area of 420.29 m{sup 2} g{sup -1}, a pore size of 1.91 nm and a saturation magnetization of 32 emu g{sup -1}. Doxorubicin (DOX) is loaded in mesopores and acid-sensitive blockers are introduced onto the orifices of the mesopores by a Schiff base linker to implement pH-dependent self-release. Folate was also introduced to improve DOX targeted delivery and endocytosis. The linkers remained intact to block pores with ferrocene valves and inhibit the diffusion of DOX at neutral pH. However, in lysosomes of cancer cells, which have a weak acidic pH, hydrolysis of the Schiff base group removes the nanovalves and allows the trapped DOX to be released. These processes are demonstrated by UV-visible absorption spectra, confocal fluorescence microscopy images and methyl thiazolyl tetrazolium assays in vitro, which suggest that the smart nanocomposite successfully integrates targeted drug delivery with internal stimulus induced self-release and is a potentially useful material for nanobiomedicine.

    3. VEGF₁₂₁-conjugated mesoporous silica nanoparticle: a tumor targeted drug delivery system.

      Science.gov (United States)

      Goel, Shreya; Chen, Feng; Hong, Hao; Valdovinos, Hector F; Hernandez, Reinier; Shi, Sixiang; Barnhart, Todd E; Cai, Weibo

      2014-12-10

      The vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) signaling cascade plays a critical role in tumor angiogenesis and metastasis and has been correlated with several poorly prognostic cancers such as malignant gliomas. Although a number of anti-VEGFR therapies have been conceived, inefficient drug administration still limits their therapeutic efficacy and raises concerns of potential side effects. In the present work, we propose the use of uniform mesoporous silica nanoparticles (MSNs) for VEGFR targeted positron emission tomography imaging and delivery of the anti-VEGFR drug (i.e., sunitinib) in human glioblastoma (U87MG) bearing murine models. MSNs were synthesized, characterized and modified with polyethylene glycol, anti-VEGFR ligand VEGF121 and radioisotope (64)Cu, followed by extensive in vitro, in vivo and ex vivo studies. Our results demonstrated that a significantly higher amount of sunitinib could be delivered to the U87MG tumor by targeting VEGFR when compared with the non-targeted counterparts. The as-developed VEGF121-conjugated MSN could become another attractive nanoplatform for the design of future theranostic nanomedicine.

    4. Complement therapeutics in inflammatory diseases: promising drug candidates for C3-targeted intervention.

      Science.gov (United States)

      Mastellos, D C; Ricklin, D; Hajishengallis, E; Hajishengallis, G; Lambris, J D

      2016-02-01

      There is increasing appreciation that complement dysregulation lies at the heart of numerous immune-mediated and inflammatory disorders. Complement inhibitors are therefore being evaluated as new therapeutic options in various clinical translation programs and the first clinically approved complement-targeted drugs have profoundly impacted the management of certain complement-mediated diseases. Among the many members of the intricate protein network of complement, the central component C3 represents a 'hot-spot' for complement-targeted therapeutic intervention. C3 modulates both innate and adaptive immune responses and is linked to diverse immunomodulatory systems and biological processes that affect human pathophysiology. Compelling evidence from preclinical disease models has shown that C3 interception may offer multiple benefits over existing therapies or even reveal novel therapeutic avenues in disorders that are not commonly regarded as complement-driven, such as periodontal disease. Using the clinically developed compstatin family of C3 inhibitors and periodontitis as illustrative examples, this review highlights emerging therapeutic concepts and developments in the design of C3-targeted drug candidates as novel immunotherapeutics for oral and systemic inflammatory diseases. PMID:26332138

    5. Neuroblastoma-targeted nanocarriers improve drug delivery and penetration, delay tumor growth and abrogate metastatic diffusion.

      Science.gov (United States)

      Cossu, Irene; Bottoni, Gianluca; Loi, Monica; Emionite, Laura; Bartolini, Alice; Di Paolo, Daniela; Brignole, Chiara; Piaggio, Francesca; Perri, Patrizia; Sacchi, Angelina; Curnis, Flavio; Gagliani, Maria Cristina; Bruno, Silvia; Marini, Cecilia; Gori, Alessandro; Longhi, Renato; Murgia, Daniele; Sementa, Angela Rita; Cilli, Michele; Tacchetti, Carlo; Corti, Angelo; Sambuceti, Gianmario; Marchiò, Serena; Ponzoni, Mirco; Pastorino, Fabio

      2015-11-01

      Selective tumor targeting is expected to enhance drug delivery and to decrease toxicity, resulting in an improved therapeutic index. We have recently identified the HSYWLRS peptide sequence as a specific ligand for aggressive neuroblastoma, a childhood tumor mostly refractory to current therapies. Here we validated the specific binding of HSYWLRS to neuroblastoma cell suspensions obtained either from cell lines, animal models, or Schwannian-stroma poor, stage IV neuroblastoma patients. Binding of the biotinylated peptide and of HSYWLRS-functionalized fluorescent quantum dots or liposomal nanoparticles was dose-dependent and inhibited by an excess of free peptide. In animal models obtained by the orthotopic implant of either MYCN-amplified or MYCN single copy human neuroblastoma cell lines, treatment with HSYWLRS-targeted, doxorubicin-loaded Stealth Liposomes increased tumor vascular permeability and perfusion, enhancing tumor penetration of the drug. This formulation proved to exert a potent antitumor efficacy, as evaluated by bioluminescence imaging and micro-PET, leading to (i) delay of tumor growth paralleled by decreased tumor glucose consumption, and (ii) abrogation of metastatic spreading, accompanied by absence of systemic toxicity and significant increase in the animal life span. Our findings are functional to the design of targeted nanocarriers with potentiated therapeutic efficacy towards the clinical translation.

    6. A lysosome-targeted drug delivery system based on sorbitol backbone towards efficient cancer therapy.

      Science.gov (United States)

      Maniganda, Santhi; Sankar, Vandana; Nair, Jyothi B; Raghu, K G; Maiti, Kaustabh K

      2014-09-14

      A straightforward synthetic approach was adopted for the construction of a lysosome-targeted drug delivery system (TDDS) using sorbitol scaffold (Sor) linked to octa-guanidine and tetrapeptide GLPG, a peptide substrate of lysosomal cysteine protease, cathepsin B. The main objective was to efficiently deliver the potential anticancer drug, doxorubicin to the target sites, thereby minimizing dose-limiting toxicity. Three TDDS vectors were synthesized viz., DDS1: Sor-GLPG-Fl, DDS2: Sor-Fl (control) and DDS3: Sor-GLPGC-SMCC-Dox. Dox release from DDS3 in the presence of cathepsin B was studied by kinetics measurement based on the fluorescent property of Dox. The cytotoxicity of DDS1 was assessed and found to be non-toxic. Cellular internalization and colocalization studies of all the 3 systems were carried out by flow cytometry and confocal microscopy utilizing cathepsin B-expressing HeLa cells. DDS1 and DDS3 revealed significant localization within the lysosomes, in contrast to DDS2 (control). The doxorubicin-conjugated carrier, DDS3, demonstrated significant cytotoxic effect when compared to free Dox by MTT assay and also by flow cytometric analysis. The targeted approach with DDS3 is expected to be promising, because it is indicated to be advantageous over free Dox, which possesses dose-limiting toxicity, posing risk of injury to normal tissues.

    7. Triphenylphosphonium Decorated Liposomes and Dendritic Polymers: Prospective Second Generation Drug Delivery Systems for Targeting Mitochondria.

      Science.gov (United States)

      Paleos, Constantinos M; Tsiourvas, Dimitris; Sideratou, Zili

      2016-07-01

      Targeting specific intracellular organelles has been a biological process of significant interest. Specifically, for mitochondrial targeting, conventional liposomal and dendritic polymer nanoparticles were selected to be presented in this miniperspective. Both types of nanoparticles were decorated on their external surface with triphenylphosphonium cation (TPP), a well-known and effective mitochondrial targeting moiety. Due to their advantageous specificity toward mitochondria, these nanoparticles may be considered as prospective second generation drug delivery systems (DDSs). Functionalized liposomal and dendritic nanoparticles are conveniently prepared, and although they encounter several hurdles on their route from the extracellular environment to the interior of mitochondria, they manage to be accumulated inside them in experiments in vitro. Therefore, the TPP-functionalized nanoparticles presented in this miniperspective can prove effective DDSs and efforts should be continued to obtain results that will trigger further studies including clinical studies, hopefully leading to effective drugs for mitochondrial diseases. In fact, since these DDSs enter and act at the site where the dysfunction exists, a new medicine subspecialty is emerging, the so-called mitochondrial medicine. PMID:27280339

    8. Nanotechnology in the targeted drug delivery for bone diseases and bone regeneration

      Directory of Open Access Journals (Sweden)

      Gu W

      2013-06-01

      Full Text Available Wenyi Gu,1,2 Chengtie Wu,3 Jiezhong Chen,1 Yin Xiao1 1Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia; 2Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia; 3State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People's Republic of China Abstract: Nanotechnology is a vigorous research area and one of its important applications is in biomedical sciences. Among biomedical applications, targeted drug delivery is one of the most extensively studied subjects. Nanostructured particles and scaffolds have been widely studied for increasing treatment efficacy and specificity of present treatment approaches. Similarly, this technique has been used for treating bone diseases including bone regeneration. In this review, we have summarized and highlighted the recent advancement of nanostructured particles and scaffolds for the treatment of cancer bone metastasis, osteosarcoma, bone infections and inflammatory diseases, osteoarthritis, as well as for bone regeneration. Nanoparticles used to deliver deoxyribonucleic acid and ribonucleic acid molecules to specific bone sites for gene therapies are also included. The investigation of the implications of nanoparticles in bone diseases have just begun, and has already shown some promising potential. Further studies have to be conducted, aimed specifically at assessing targeted delivery and bioactive scaffolds to further improve their efficacy before they can be used clinically. Keywords: nanoparticles, nanostructured scaffold, cancer bone metastasis, bone diseases, target drug delivery, bone regeneration

    9. Cholesterol-modified poly(lactide-co-glycolide) nanoparticles for tumor-targeted drug delivery.

      Science.gov (United States)

      Lee, Jeong-Jun; Lee, Song Yi; Park, Ju-Hwan; Kim, Dae-Duk; Cho, Hyun-Jong

      2016-07-25

      Poly(lactide-co-glycolide)-cholesterol (PLGA-C)-based nanoparticles (NPs) were developed for the tumor-targeted delivery of curcumin (CUR). PLGA-C/CUR NPs with ∼200nm mean diameter, narrow size distribution, and neutral zeta potential were fabricated by a modified emulsification-solvent evaporation method. The existence of cholesterol moiety in PLGA-C copolymer was confirmed by proton nuclear magnetic resonance ((1)H NMR) analysis. In vitro stability of developed NPs after 24h incubation was confirmed in phosphate buffered saline (PBS) and serum media. Sustained (∼6days) and pH-responsive drug release profiles from PLGA-C NPs were presented. Blank PLGA and PLGA-C NPs exhibited a negligible cytotoxicity in Hep-2 (human laryngeal carcinoma) cells in the tested concentration range. According to the results of flow cytometry and confocal laser scanning microscopy (CLSM) studies, PLGA-C NPs presented an improved cellular accumulation efficiency, compared to PLGA NPs, in Hep-2 cells. Enhanced in vivo tumor targetability of PLGA-C NPs, compared to PLGA NPs, in Hep-2 tumor-xenografted mouse model was also verified by a real-time near-infrared fluorescence (NIRF) imaging study. Developed PLGA-C NPs may be a candidate of efficient and biocompatible nanosystems for tumor-targeted drug delivery and cancer imaging. PMID:27286639

    10. Dual-targeting anti-angiogenic cyclic peptides as potential drug leads for cancer therapy

      Science.gov (United States)

      Chan, Lai Yue; Craik, David J.; Daly, Norelle L.

      2016-01-01

      Peptide analogues derived from bioactive hormones such as somatostatin or certain growth factors have great potential as angiogenesis inhibitors for cancer applications. In an attempt to combat emerging drug resistance many FDA-approved anti-angiogenesis therapies are co-administered with cytotoxic drugs as a combination therapy to target multiple signaling pathways of cancers. However, cancer therapies often encounter limiting factors such as high toxicities and side effects. Here, we combined two anti-angiogenic epitopes that act on different pathways of angiogenesis into a single non-toxic cyclic peptide framework, namely MCoTI-II (Momordica cochinchinensis trypsin inhibitor-II), and subsequently assessed the anti-angiogenic activity of the novel compound. We hypothesized that the combination of these two epitopes would elicit a synergistic effect by targeting different angiogenesis pathways and result in improved potency, compared to that of a single epitope. This novel approach has resulted in the development of a potent, non-toxic, stable and cyclic analogue with nanomolar potency inhibition in in vitro endothelial cell migration and in vivo chorioallantoic membrane angiogenesis assays. This is the first report to use the MCoTI-II framework to develop a 2-in-1 anti-angiogenic peptide, which has the potential to be used as a form of combination therapy for targeting a wide range of cancers. PMID:27734947

    11. Understanding the biology of the Plasmodium falciparum apicoplast; an excellent target for antimalarial drug development.

      Science.gov (United States)

      Chakraborty, Arnish

      2016-08-01

      Malaria is a life-threatening tropical disease, caused by the intracellular parasite Plasmodium falciparum. The World Health Organization counts malaria as one of the top ten causes of worldwide death. The unavailability of a successful malaria vaccine and the ever-increasing instances of drug resistance in the malaria parasite demand the discovery of new targets within P. falciparum for the development of next generation antimalarials. Fortunately, all apicomplexan parasites, including P. falciparum harbor a relict, non-photosynthetic plastid known as the apicoplast. The apicoplast is a semi-autonomous organelle within P. falciparum containing a 35kb circular genome. Despite a genome of its own, majority of the apicoplast proteins are encoded by the parasite nucleus and imported into the apicoplast. The organelle has been shown to be essential to P. falciparum survival and the loss the apicoplast manifests as a 'delayed death' response in the parasite. The apicoplast has evolved out of cyanobacteria in a complex, two step endosymbiotic event. As a result the architecture and the gene expression machinery of the apicoplast is quite bacteria-like and is susceptible to a wide range of antibiotics such as fosmidomycin, tetracycline, azithromycin, clindamycin and triclosan. The biosynthetic pathways for isoprenoids, fatty acids and heme operate within the malaria apicoplast, making the organelle an excellent target for drug development. The review focuses on the evolution, biology and the essentiality of the apicoplast within the malaria parasite and discusses some of the recent achievements towards the design and discovery of apicoplast targeted antimalarial compounds.

    12. Metabolic network analysis predicts efficacy of FDA-approved drugs targeting the causative agent of a neglected tropical disease

      Directory of Open Access Journals (Sweden)

      Chavali Arvind K

      2012-04-01

      Full Text Available Abstract Background Systems biology holds promise as a new approach to drug target identification and drug discovery against neglected tropical diseases. Genome-scale metabolic reconstructions, assembled from annotated genomes and a vast array of bioinformatics/biochemical resources, provide a framework for the interrogation of human pathogens and serve as a platform for generation of future experimental hypotheses. In this article, with the application of selection criteria for both Leishmania major targets (e.g. in silico gene lethality and drugs (e.g. toxicity, a method (MetDP to rationally focus on a subset of low-toxic Food and Drug Administration (FDA-approved drugs is introduced. Results This metabolic network-driven approach identified 15 L. major genes as high-priority targets, 8 high-priority synthetic lethal targets, and 254 FDA-approved drugs. Results were compared to previous literature findings and existing high-throughput screens. Halofantrine, an antimalarial agent that was prioritized using MetDP, showed noticeable antileishmanial activity when experimentally evaluated in vitro against L. major promastigotes. Furthermore, synthetic lethality predictions also aided in the prediction of superadditive drug combinations. For proof-of-concept, double-drug combinations were evaluated in vitro against L. major and four combinations involving the drug disulfiram that showed superadditivity are presented. Conclusions A direct metabolic network-driven method that incorporates single gene essentiality and synthetic lethality predictions is proposed that generates a set of high-priority L. major targets, which are in turn associated with a select number of FDA-approved drugs that are candidate antileishmanials. Additionally, selection of high-priority double-drug combinations might provide for an attractive and alternative avenue for drug discovery against leishmaniasis.

    13. A comprehensive overview of exosomes as drug delivery vehicles - endogenous nanocarriers for targeted cancer therapy.

      Science.gov (United States)

      Johnsen, Kasper Bendix; Gudbergsson, Johann Mar; Skov, Martin Najbjerg; Pilgaard, Linda; Moos, Torben; Duroux, Meg

      2014-08-01

      Exosomes denote a class of secreted nanoparticles defined by size, surface protein and lipid composition, and the ability to carry RNA and proteins. They are important mediators of intercellular communication and regulators of the cellular niche, and their altered characteristics in many diseases, such as cancer, suggest them to be important both for diagnostic and therapeutic purposes, prompting the idea of using exosomes as drug delivery vehicles, especially for gene therapy. This review covers the current status of evidence presented in the field of exosome-based drug delivery systems. Components for successful exosome-based drug delivery, such as choice of donor cell, therapeutic cargo, use of targeting peptide, loading method and administration route are highlighted and discussed with a general focus pertaining to the results obtained in models of different cancer types. In addition, completed and on-going clinical trials are described, evaluating exosome-based therapies for the treatment of different cancer types. Due to their endogenous origin, exosome-based drug delivery systems may have advantages in the treatment of cancer, but their design needs further refinement to justify their usage on the clinical scale.

    14. Quantitatively integrating molecular structure and bioactivity profile evidence into drug-target relationship analysis

      Directory of Open Access Journals (Sweden)

      Xu Tianlei

      2012-05-01

      Full Text Available Abstract Background Public resources of chemical compound are in a rapid growth both in quantity and the types of data-representation. To comprehensively understand the relationship between the intrinsic features of chemical compounds and protein targets is an essential task to evaluate potential protein-binding function for virtual drug screening. In previous studies, correlations were proposed between bioactivity profiles and target networks, especially when chemical structures were similar. With the lack of effective quantitative methods to uncover such correlation, it is demanding and necessary for us to integrate the information from multiple data sources to produce an comprehensive assessment of the similarity between small molecules, as well as quantitatively uncover the relationship between compounds and their targets by such integrated schema. Results In this study a multi-view based clustering algorithm was introduced to quantitatively integrate compound similarity from both bioactivity profiles and structural fingerprints. Firstly, a hierarchy clustering was performed with the fused similarity on 37 compounds curated from PubChem. Compared to clustering in a single view, the overall common target number within fused classes has been improved by using the integrated similarity, which indicated that the present multi-view based clustering is more efficient by successfully identifying clusters with its members sharing more number of common targets. Analysis in certain classes reveals that mutual complement of the two views for compound description helps to discover missing similar compound when only single view was applied. Then, a large-scale drug virtual screen was performed on 1267 compounds curated from Connectivity Map (CMap dataset based on the fused similarity, which obtained a better ranking result compared to that of single-view. These comprehensive tests indicated that by combining different data representations; an improved

    15. An integrated structure- and system-based framework to identify new targets of metabolites and known drugs

      KAUST Repository

      Naveed, Hammad

      2015-08-18

      Motivation: The inherent promiscuity of small molecules towards protein targets impedes our understanding of healthy versus diseased metabolism. This promiscuity also poses a challenge for the pharmaceutical industry as identifying all protein targets is important to assess (side) effects and repositioning opportunities for a drug. Results: Here, we present a novel integrated structure- and system-based approach of drug-target prediction (iDTP) to enable the large-scale discovery of new targets for small molecules, such as pharmaceutical drugs, co-factors and metabolites (collectively called ‘drugs’). For a given drug, our method uses sequence order–independent structure alignment, hierarchical clustering, and probabilistic sequence similarity to construct a probabilistic pocket ensemble (PPE) that captures promiscuous structural features of different binding sites on known targets. A drug’s PPE is combined with an approximation of its delivery profile to reduce false positives. In our cross-validation study, we use iDTP to predict the known targets of eleven drugs, with 63% sensitivity and 81% specificity. We then predicted novel targets for these drugs—two that are of high pharmacological interest, the nuclear receptor PPARγ and the oncogene Bcl-2, were successfully validated through in vitro binding experiments. Our method is broadly applicable for the prediction of protein-small molecule interactions with several novel applications to biological research and drug development.

    16. Targeted Drug Delivery to the Brain by MRI-guided Focused Ultrasound

      Science.gov (United States)

      Treat, Lisa Hsu; McDannold, Nathan; Vykhodtseva, Natalia; Zhang, Yongzhi; Tam, Karen; Hynynen, Kullervo

      2006-05-01

      The effect of focused ultrasound on the absorption of liposome-encapsulated doxorubicin in the brain was investigated. By applying focused ultrasound in the presence of microbubble ultrasound contrast agent, we achieved targeted drug delivery to the brain in vivo. Tissue drug concentrations in sonicated brain corresponded with cytotoxic levels measured in various human tumors and were significantly different from those measured in unexposed contralateral control samples (p ⩽ 0.02). In addition, increased MR signal enhancement at the focal location on contrast-enhanced T1-weighted fast spin echo images correlated with increased penetration of doxorubicin into brain tissue (r = 0.85), indicating the potential of MRI to be used as an indicator of blood-brain barrier permeability during treatment. Further investigation is required to evaluate the efficacy of this technique and to optimize its parameters for clinical application.

    17. Multifunctional hybrid-carbon nanotubes: new horizon in drug delivery and targeting.

      Science.gov (United States)

      Mehra, Neelesh Kumar; Jain, Narendra Kumar

      2016-01-01

      Carbon nanotubes (CNTs) have emerged as an intriguing nanotechnological tool for numerous biomedical applications including biocompatible modules for the bioactives delivery ascribed to their unique properties, such as greater loading efficiency, biocompatibility, non-immunogenicity, high surface area and photoluminescence, that make them ideal candidate in pharmaceutical and biomedical science. The design of multifunctional hybrid-CNTs for drug delivery and targeting may differ from the conventional drug delivery system. The conventional nanocarriers have few limitations, such as inappropriate availability of surface-chemical functional groups for conjugation, low entrapment/loading efficiency as well as stability as per ICH guidelines with generally regarded as safe (GRAS) prominences. The multifunctional hybrid-CNTs will sparked and open a new door for researchers, scientist of the pharmaceutical and biomedical arena. This review summarizes the vivid aspects of CNTs like characterization, supramolecular chemistry of CNTs-dendrimer, CNTs-nanoparticles, CNTs-quantum dots conjugate for delivery of bioactives, not discussed so far. PMID:26147085

    18. Biosynthetic Machinery Involved in Aberrant Glycosylation: Promising Targets for Development Drugs Against Cancer

      Directory of Open Access Journals (Sweden)

      Andreia eVasconcelos-dos-Santos

      2015-06-01

      Full Text Available Cancer cells depend on altered metabolism and nutrient uptake to generate and keep the malignant phenotype. The hexosamine biosynthetic pathway (HBP is a branch of glucose metabolism that produces UDP-GlcNAc, and its derivatives, UDP-GalNAc and CMP-Neu5Ac, donor substrates used in the production of glycoproteins and glycolipids. Growing evidence demonstrates that alteration of the pool of activated substrates might lead to different glycosylation and cell signaling. It is already well established that aberrant glycosylation can modulate tumor growth and malignant transformation in different cancer types. Therefore, biosynthetic machinery involved in the assembly of aberrant glycans are becoming prominent targets for anti-tumor drugs. This review describes three classes of glycosylation, O-GlcNAcylation, N-linked and mucin type O-linked glycosylation, involved in tumor progression, their biosynthesis and highlights the available inhibitors as potential anti-tumor drugs.

    19. Brain Targeting of a Water Insoluble Antipsychotic Drug Haloperidol via the Intranasal Route Using PAMAM Dendrimer.

      Science.gov (United States)

      Katare, Yogesh K; Daya, Ritesh P; Sookram Gray, Christal; Luckham, Roger E; Bhandari, Jayant; Chauhan, Abhay S; Mishra, Ram K

      2015-09-01

      Delivery of therapeutics to the brain is challenging because many organic molecules have inadequate aqueous solubility and limited bioavailability. We investigated the efficiency of a dendrimer-based formulation of a poorly aqueous soluble drug, haloperidol, in targeting the brain via intranasal and intraperitoneal administration. Aqueous solubility of haloperidol was increased by more than 100-fold in the developed formulation. Formulation was assessed via different routes of administration for behavioral (cataleptic and locomotor) responses, and for haloperidol distribution in plasma and brain tissues. Dendrimer-based formulation showed significantly higher distribution of haloperidol in the brain and plasma compared to a control formulation of haloperidol administered via intraperitoneal injection. Additionally, 6.7 times lower doses of the dendrimer-haloperidol formulation administered via the intranasal route produced behavioral responses that were comparable to those induced by haloperidol formulations administered via intraperitoneal injection. This study demonstrates the potential of dendrimer in improving the delivery of water insoluble drugs to brain.

    20. Designing of Anti Dengue Drug Molecule against Insilico Modeled Target DC-Sign (CD-209

      Directory of Open Access Journals (Sweden)

      Prashantha C.N

      2013-09-01

      Full Text Available The C-type lectin DC-SIGN (CD209 plays a major role in receptor on human dendritic cells, it binds to several glycoproteins of viruses that facilitate disease progression. In dengue fever, the disease targets of arbovirus infection, show dendritic and reticuloendothelial cells that may affect immune system. The phytochemical extracts of Bosenbergia rotunda (BR have been effectively used as potential small molecular inhibitors to inhibit DC-SIGN (CD209 function. Using rational drug designing the training sets include Panduratin-A and 4-hydroxypanduratin is designed from BR derivatives could be an effective inhibitor of a DC-SIGN (CD209 binding towards the drug discovery/ therapy against dengue fever.

    1. Non-Target Screening of Veterinary Drugs Using Tandem Mass Spectrometry on SmartMass

      Science.gov (United States)

      Xia, Bing; Liu, Xin; Gu, Yu-Cheng; Zhang, Zhao-Hui; Wang, Hai-Yan; Ding, Li-Sheng; Zhou, Yan

      2013-05-01

      Non-target screening of veterinary drugs using tandem mass spectrometric data was performed on the SmartMass platform. This newly developed software uses the characteristic fragmentation patterns (CFP) to identify chemicals, especially those containing particular substructures. A mixture of 17 sulfonamides was separated by ultra performance liquid chromatography (UPLC), and SmartMass was used to process the tandem mass spectrometry (MS/MS) data acquired on an Orbitrap mass spectrometer. The data were automatically extracted, and each sulfonamide was recognized and analyzed with a prebuilt analysis rule. By using this software, over 98 % of the false candidate structures were eliminated, and all the correct structures were found within the top 10 of the ranking lists. Furthermore, SmartMass could also be used to identify slightly modified contraband drugs and metabolites with simple prebuilt rules. [Figure not available: see fulltext.

    2. In situ crosslinked smart polypeptide nanoparticles for multistage responsive tumor-targeted drug delivery

      Science.gov (United States)

      Yi, Huqiang; Liu, Peng; Sheng, Nan; Gong, Ping; Ma, Yifan; Cai, Lintao

      2016-03-01

      Smart tumor-targeted drug delivery is crucial for improving the effect of chemotherapy and reducing the adverse effects. Here, we synthesized a smart polypeptide copolymer based on n-butylamine-poly(l-lysine)-b-poly(l-cysteine) (PLL-PLC) with functionalization of folic acid (FA) and 1,2-dicarboxylic-cyclohexene anhydride (DCA) for multistage responsive tumor-targeted drug delivery. The copolymers (FA-PLL(DCA)-PLC) spontaneously crosslinked in situ to form redox and pH dual responsive FA-PLL(DCA)-PLC nanoparticles (FD-NPs), which had a reversible zeta potential around -30 mV at pH 7.4, but switched to +15 mV at pH 5.0. Moreover, FD-NPs effectively loaded DOX with a loading capacity at 15.7 wt%. At pH 7.4, only 24.5% DOX was released within 60 h. However, at pH 5.0, the presence of 10 mM DTT dramatically accelerated DOX release with over 90% of DOX released within 10 h. Although the FD-NPs only enhanced DOX uptake in FA receptor positive (FR+) cancer cells at pH 7.4, a weak acidic condition promoted FD-NP-facilitated DOX uptake in both FR+ HeLa and FR- A549 cells, as well as significantly improving cellular binding and end/lysosomal escape. In vivo studies in a HeLa cancer model demonstrated that the charge-reversible FD-NPs delivered DOX into tumors more effectively than charge-irreversible nanoparticles. Hence, these multistage responsive FD-NPs would serve as highly efficient drug vectors for targeted cancer chemotherapy.Smart tumor-targeted drug delivery is crucial for improving the effect of chemotherapy and reducing the adverse effects. Here, we synthesized a smart polypeptide copolymer based on n-butylamine-poly(l-lysine)-b-poly(l-cysteine) (PLL-PLC) with functionalization of folic acid (FA) and 1,2-dicarboxylic-cyclohexene anhydride (DCA) for multistage responsive tumor-targeted drug delivery. The copolymers (FA-PLL(DCA)-PLC) spontaneously crosslinked in situ to form redox and pH dual responsive FA-PLL(DCA)-PLC nanoparticles (FD-NPs), which had a reversible

    3. Multifunctional aptamer-based nanoparticles for targeted drug delivery to circumvent cancer resistance.

      Science.gov (United States)

      Liu, Juan; Wei, Tuo; Zhao, Jing; Huang, Yuanyu; Deng, Hua; Kumar, Anil; Wang, Chenxuan; Liang, Zicai; Ma, Xiaowei; Liang, Xing-Jie

      2016-06-01

      By its unique advantages over traditional medicine, nanomedicine has offered new strategies for cancer treatment. In particular, the development of drug delivery strategies has focused on nanoscale particles to improve bioavailability. However, many of these nanoparticles are unable to overcome tumor resistance to chemotherapeutic agents. Recently, new opportunities for drug delivery have been provided by oligonucleotides that can self-assemble into three-dimensional nanostructures. In this work, we have designed and developed functional DNA nanostructures to deliver the chemotherapy drug doxorubicin (Dox) to resistant cancer cells. These nanostructures have two components. The first component is a DNA aptamer, which forms a dimeric G-quadruplex nanostructure to target cancer cells by binding with nucleolin. The second component is double-stranded DNA (dsDNA), which is rich in -GC- base pairs that can be applied for Dox delivery. We demonstrated that Dox was able to efficiently intercalate into dsDNA and this intercalation did not affect the aptamer's three-dimensional structure. In addition, the Aptamer-dsDNA (ApS) nanoparticle showed good stability and protected the dsDNA from degradation in bovine serum. More importantly, the ApS&Dox nanoparticle efficiently reversed the resistance of human breast cancer cells to Dox. The mechanism circumventing doxorubicin resistance by ApS&Dox nanoparticles may be predominantly by cell cycle arrest in S phase, effectively increased cell uptake and decreased cell efflux of doxorubicin. Furthermore, the ApS&Dox nanoparticles could effectively inhibit tumor growth, while less cardiotoxicity was observed. Overall, this functional DNA nanostructure provides new insights into the design of nanocarriers to overcome multidrug resistance through targeted drug delivery. PMID:26994877

    4. AVN-101: A Multi-Target Drug Candidate for the Treatment of CNS Disorders.

      Science.gov (United States)

      Ivachtchenko, Alexandre V; Lavrovsky, Yan; Okun, Ilya

      2016-05-25

      Lack of efficacy of many new highly selective and specific drug candidates in treating diseases with poorly understood or complex etiology, as are many of central nervous system (CNS) diseases, encouraged an idea of developing multi-modal (multi-targeted) drugs. In this manuscript, we describe molecular pharmacology, in vitro ADME, pharmacokinetics in animals and humans (part of the Phase I clinical studies), bio-distribution, bioavailability, in vivo efficacy, and safety profile of the multimodal drug candidate, AVN-101. We have carried out development of a next generation drug candidate with a multi-targeted mechanism of action, to treat CNS disorders. AVN-101 is a very potent 5-HT7 receptor antagonist (Ki = 153 pM), with slightly lesser potency toward 5-HT6, 5-HT2A, and 5HT-2C receptors (Ki = 1.2-2.0 nM). AVN-101 also exhibits a rather high affinity toward histamine H1 (Ki = 0.58 nM) and adrenergic α2A, α2B, and α2C (Ki = 0.41-3.6 nM) receptors. AVN-101 shows a good oral bioavailability and facilitated brain-blood barrier permeability, low toxicity, and reasonable efficacy in animal models of CNS diseases. The Phase I clinical study indicates the AVN-101 to be well tolerated when taken orally at doses of up to 20 mg daily. It does not dramatically influence plasma and urine biochemistry, nor does it prolong QT ECG interval, thus indicating low safety concerns. The primary therapeutic area for AVN-101 to be tested in clinical trials would be Alzheimer's disease. However, due to its anxiolytic and anti-depressive activities, there is a strong rational for it to also be studied in such diseases as general anxiety disorders, depression, schizophrenia, and multiple sclerosis. PMID:27232215

    5. A new kind of magnetic targeting induction heating drug carrier and its physical and biological properties

      Institute of Scientific and Technical Information of China (English)

      2009-01-01

      Nano-carbon and iron composite―carbon-coated iron nanoparticles (CCINs) produced by carbon arc method can be used as a new kind of magnetic targeting induction heating drug carrier for cancer therapy. The structure and morphology of CCINs are studied by X-ray diffraction (XRD) and transmission electron microscope (TEM). Mossbauer spectra of these nanoparticles show that they contain only iron and carbon, without ferric carbide and ferric oxide. CCINs can be used as the magnetic drug carrier, with the effect of targeting magnetic induction heating in its inner core and higher drug adsorption in its nano-carbon shell outside because of its high specific surface area. CCINs can absorb Epirubicin (EPI) of 160 μg/mg measured by an optical spectrometer. In acute toxicity experiment with mice, the median lethal dose (LD50) of EPI is 16.9 mg/kg, while that of EPI-CCINs mixture is 20.7 mg/kg and none of the mice died after pure CCINs medication. The results show that pure CCINs belong to non-toxic grade and EPI delivery in mixture with CCINs can reduce its acute toxicity in mice. The magnetic properties of CCINs and their magnetic induction heating are investigated. The iron nanoparticle in its inner core has better magnetism with a good effect on targeting magnetic induction heating. When the CCINs are mixed with physiological salt water and are injected uniformly in pig’s liver, the temperature goes up to 48℃. While in the case that CCINs are filled in a certain section of pig’s liver, the temperature goes up to 52℃. In both cases the temperature is high enough to kill the cancer cell. CCINs have potential applications in cancer therapy.

    6. Development of Drugs Targeting the PI3K Signalling Pathway in Leukaemias and Lymphomas

      Directory of Open Access Journals (Sweden)

      Alexandre Arcaro

      2015-03-01

      Full Text Available The phosphoinositide 3-kinase (PI3K family of signalling enzymes play a key role in the transduction of signals from activated cell surface receptors controlling cell growth and proliferation, survival, metabolism, and migration. The intracellular signalling pathway from activated receptors to PI3K and its downstream targets v-akt murine thymoma viral oncogene homolog (Akt and mechanistic target of rapamycin (mTOR is very frequently deregulated by genetic and epigenetic mechanisms in human cancer, including leukaemia and lymphoma. In the past decade, an arsenal of small molecule inhibitors of key enzymes in this pathway has been developed and evaluated in pre-clinical studies and clinical trials in cancer patients. These include pharmacological inhibitors of Akt, mTOR, and PI3K, some of which are approved for the treatment of leukaemia and lymphoma. The PI3K family comprises eight different catalytic isoforms in humans, which have been subdivided into three classes. Class I PI3K isoforms have been extensively studied in the context of human cancer, and the isoforms p110α and p110δ are validated drug targets. The recent approval of a p110δ-specific PI3K inhibitor (idelalisib/Zydelig® for the treatment of selected B cell malignancies represents the first success in developing these molecules into anti-cancer drugs. In addition to PI3K inhibitors, mTOR inhibitors are intensively studied in leukaemia and lymphoma, and temsirolimus (Torisel® is approved for the treatment of a type of lymphoma. Based on these promising results it is hoped that additional novel PI3K pathway inhibitors will in the near future be further developed into new drugs for leukaemia and lymphoma.

    7. Selection between Michaelis-Menten and target-mediated drug disposition pharmacokinetic models.

      Science.gov (United States)

      Yan, Xiaoyu; Mager, Donald E; Krzyzanski, Wojciech

      2010-02-01

      Target-mediated drug disposition (TMDD) models have been applied to describe the pharmacokinetics of drugs whose distribution and/or clearance are affected by its target due to high binding affinity and limited capacity. The Michaelis-Menten (M-M) model has also been frequently used to describe the pharmacokinetics of such drugs. The purpose of this study is to investigate conditions for equivalence between M-M and TMDD pharmacokinetic models and provide guidelines for selection between these two approaches. Theoretical derivations were used to determine conditions under which M-M and TMDD pharmacokinetic models are equivalent. Computer simulations and model fitting were conducted to demonstrate these conditions. Typical M-M and TMDD profiles were simulated based on literature data for an anti-CD4 monoclonal antibody (TRX1) and phenytoin administered intravenously. Both models were fitted to data and goodness of fit criteria were evaluated for model selection. A case study of recombinant human erythropoietin was conducted to qualify results. A rapid binding TMDD model is equivalent to the M-M model if total target density R ( tot ) is constant, and R ( tot ) K ( D ) /(K ( D ) + C) ( 2 ) < 1 where K ( D ) represents the dissociation constant and C is the free drug concentration. Under these conditions, M-M parameters are defined as: V ( max ) = k ( int ) R ( tot ) V ( c ) and K ( m ) = K ( D ) where k ( int ) represents an internalization rate constant, and V ( c ) is the volume of the central compartment. R ( tot ) is constant if and only if k ( int ) = k ( deg,) where k ( deg ) is a degradation rate constant. If the TMDD model predictions are not sensitive to k ( int ) or k ( deg ) parameters, the condition of R ( tot ) K ( D ) /(K ( D ) + C) ( 2 ) < 1 alone can preserve the equivalence between rapid binding TMDD and M-M models. The model selection process for drugs that exhibit TMDD should involve a full mechanistic model as well as reduced models. The best model

    8. Synthetic Nano-Low Density Lipoprotein as Targeted Drug DeliveryVehicle for Glioblastoma Multiforme

      Energy Technology Data Exchange (ETDEWEB)

      Nikanjam, Mina; Blakely, Eleanor A.; Bjornstad, Kathleen A.; Shu,Xiao; Budinger, Thomas F.; Forte, Trudy M.

      2006-06-14

      This paper discribes a synthetic low density lipoprotein(LDL) made by complexing a 29 amino acid that consists of a lipid bindingdomain and the LDL receptor binding domain with a lipid microemulsion.The nano-LDL particles were intermdiate in size between LDL and HDL andbound to LDL receptors on GBM brain tumor cells. Synthetic nano-LDLuptake by GBM cells was LDL receptor specific and dependent on cellreceptor number. It is suggested that these synthetic particles can serveas a delivery vehicle for hydophobic anti-tumor drugs by targeting theLDL receptor.

    9. Parasite Mitogen-Activated Protein Kinases as Drug Discovery Targets to Treat Human Protozoan Pathogens

      Directory of Open Access Journals (Sweden)

      Michael J. Brumlik

      2011-01-01

      Full Text Available Protozoan pathogens are a highly diverse group of unicellular organisms, several of which are significant human pathogens. One group of protozoan pathogens includes obligate intracellular parasites such as agents of malaria, leishmaniasis, babesiosis, and toxoplasmosis. The other group includes extracellular pathogens such as agents of giardiasis and amebiasis. An unfortunate unifying theme for most human protozoan pathogens is that highly effective treatments for them are generally lacking. We will review targeting protozoan mitogen-activated protein kinases (MAPKs as a novel drug discovery approach towards developing better therapies, focusing on Plasmodia, Leishmania, and Toxoplasma, about which the most is known.

    10. Importance of polar solvation and configurational entropy for design of antiretroviral drugs targeting HIV-1 protease.

      Science.gov (United States)

      Kar, Parimal; Lipowsky, Reinhard; Knecht, Volker

      2013-05-16

      Both KNI-10033 and KNI-10075 are high affinity preclinical HIV-1 protease (PR) inhibitors with affinities in the picomolar range. In this work, the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method has been used to investigate the potency of these two HIV-1 PR inhibitors against the wild-type and mutated proteases assuming that potency correlates with the affinity of the drugs for the target protein. The decomposition of the binding free energy reveals the origin of binding affinities or mutation-induced affinity changes. Our calculations indicate that the mutation I50V causes drug resistance against both inhibitors. On the other hand, we predict that the mutant I84V causes drug resistance against KNI-10075 while KNI-10033 is more potent against the I84V mutant compared to wild-type protease. Drug resistance arises mainly from unfavorable shifts in van der Waals interactions and configurational entropy. The latter indicates that neglecting changes in configurational entropy in the computation of relative binding affinities as often done is not appropriate in general. For the bound complex PR(I50V)-KNI-10075, an increased polar solvation free energy also contributes to the drug resistance. The importance of polar solvation free energies is revealed when interactions governing the binding of KNI-10033 or KNI-10075 to the wild-type protease are compared to the inhibitors darunavir or GRL-06579A. Although the contributions from intermolecular electrostatic and van der Waals interactions as well as the nonpolar component of the solvation free energy are more favorable for PR-KNI-10033 or PR-KNI-10075 compared to PR-DRV or PR-GRL-06579A, both KNI-10033 and KNI-10075 show a similar affinity as darunavir and a lower binding affinity relative to GRL-06579A. This is because of the polar solvation free energy which is less unfavorable for darunavir or GRL-06579A relative to KNI-10033 or KNI-10075. The importance of the polar solvation as revealed here

    11. Synthesis, characterization and target protein binding of drug-conjugated quantum dots in vitro and in living cells

      International Nuclear Information System (INIS)

      Elucidation of unknown target proteins of a drug is of great importance in understanding cell biology and drug discovery. There have been extensive studies to discover and identify target proteins in the cell. Visualization of targets using drug-conjugated probes has been an important approach to gathering mechanistic information of drug action at the cellular level. As quantum dot (QD) nanocrystals have attracted much attention as a fluorescent probe in the bioimaging area, we prepared drug-conjugated QD to explore the potential of target discovery. As a model drug, we selected a well-known anticancer drug, methotrexate (MTX), which has been known to target dihydrofolate reductase (DHFR) with high affinity binding (Kd = 0.54 nM). MTX molecules were covalently attached to amino-PEG-polymer-coated QDs. Specific interactions of MTX-conjugated QDs with DHFR were identified using agarose gel electrophoresis and fluorescence microscopy. Cellular uptake of the MTX-conjugated QDs in living CHO cells was investigated with regard to their localization and distribution pattern. MTX–QD was found to be internalized into the cells via caveolae-medicated endocytosis without significant sequestration in endosomes. A colocalization experiment of the MTX–QD conjugate with antiDHFR-TAT-QD also confirmed that MTX–QD binds to the target DHFR. This study showed the potential of the drug-QD conjugate to identify or visualize drug–target interactions in the cell, which is currently of great importance in the area of drug discovery and chemical biology. (paper)

    12. Enzymatic synthesis of antibody-human serum albumin conjugate for targeted drug delivery using tyrosinase from Agaricus bisporus

      OpenAIRE

      Rollett, Alexandra; Thallinger, Barbara; Ohradanova-Repic, Anna; Machacek, Christian; Walenta, Evelyn; Paulo, Artur Cavaco; Birner-Gruenberger, Ruth; Bogner-Strauss, Juliane G.; Stockinger, Hannes; Guebitz, G.M.

      2013-01-01

      Highly specific targeted drug delivery devices can be obtained with antibody-human serum albumin (mAb-HSA) conjugates. However, their conventional production involves several reaction steps including chemical modification and activation of both proteins followed by cross-linking often involving toxic chemicals. Here, we describe the enzymatic synthesis of mAb-HSA conjugates for targeted drug delivery devices using tyrosinase from Agaricus bisporus under mild reaction conditions (pH 6.8, 25 [d...

    13. Drug target prediction and prioritization: using orthology to predict essentiality in parasite genomes

      Directory of Open Access Journals (Sweden)

      Hall Ross S

      2010-04-01

      Full Text Available Abstract Background New drug targets are urgently needed for parasites of socio-economic importance. Genes that are essential for parasite survival are highly desirable targets, but information on these genes is lacking, as gene knockouts or knockdowns are difficult to perform in many species of parasites. We examined the applicability of large-scale essentiality information from four model eukaryotes, Caenorhabditis elegans, Drosophila melanogaster, Mus musculus and Saccharomyces cerevisiae, to discover essential genes in each of their genomes. Parasite genes that lack orthologues in their host are desirable as selective targets, so we also examined prediction of essential genes within this subset. Results Cross-species analyses showed that the evolutionary conservation of genes and the presence of essential orthologues are each strong predictors of essentiality in eukaryotes. Absence of paralogues was also found to be a general predictor of increased relative essentiality. By combining several orthology and essentiality criteria one can select gene sets with up to a five-fold enrichment in essential genes compared with a random selection. We show how quantitative application of such criteria can be used to predict a ranked list of potential drug targets from Ancylostoma caninum and Haemonchus contortus - two blood-feeding strongylid nematodes, for which there are presently limited sequence data but no functional genomic tools. Conclusions The present study demonstrates the utility of using orthology information from multiple, diverse eukaryotes to predict essential genes. The data also emphasize the challenge of identifying essential genes among those in a parasite that are absent from its host.

    14. Associations Between Target Lesion Restenosis and Drug-Eluting Balloon Use: An Observational Study.

      Science.gov (United States)

      Lee, Wei-Chieh; Wu, Chiung-Jen; Chen, Yung-Lung; Chung, Wen-Jung; Hsueh, Shu-Kai; Hang, Chi-Ling; Fang, Chih-Yuan; Fang, Hsiu-Yu

      2016-01-01

      Percutaneous coronary interventions (PCIs) with drug-eluting balloons (DEBs) have emerged as an adjunctive treatment for in-stent restenosis (ISR) lesions. However, recurrent restenosis still occurs following DEB use. Our study aimed to identify the associations of target lesion restenosis following DEB use over a 1-year clinical follow-up.Between November 2011 and May 2014, 246 patients were diagnosed with coronary artery ISR in our hospital. A total of 335 coronary ISR lesions were treated with DEBs. The 1-year patent coronary artery group was defined as those with negative noninvasive examinations and no clinical symptoms, or those with no angiographic restenosis. The 1-year current restenosis group was defined as those with angiographic restenosis. Clinical results were compared between 2 groups. Univariate and multivariate cox regression analyses were performed to identify the associations of target lesion restenosis following DEB use.Patients' average age was 64.96 ± 10.68 years, and 77.2% were men. Non-ST segment elevation myocardial infarction was more frequent as the clinical presentation in the 1-year current restenosis group, whereas stable angina was more frequent in the 1-year patent coronary artery group. The 1-year current restenosis group exhibited higher percentages of comorbidities, including hypertension, diabetes, prior myocardial infarction, heart failure, prior coronary artery bypass grafting, and end-stage renal disease (ESRD). Regardless of ostial ISR or nonostial ISR, the results of drug-eluting stent ISR were worse than those for bare-metal stent ISR. Multivariate analysis revealed that ESRD, and coronary ostial lesion, and the severity of pre-PCI stenosis were independently associated with target lesion restenosis following DEB use (P = 0.020, P = 0.009, P = 0.026, respectively).ESRD, and coronary ostial lesion, and the severity of pre-PCI stenosis were independently associated with recurrent target lesion restenosis

    15. Formulation of Functionalized PLGA-PEG Nanoparticles for In Vivo Targeted Drug Delivery

      Science.gov (United States)

      Cheng, Jianjun; Teply, Benjamin A.; Sherifi, Ines; Sung, Josephine; Luther, Gaurav; Gu, Frank X.; Levy-Nissenbaum, Etgar; Radovic-Moreno, Aleksandar F.; Langer, Robert; Farokhzad, Omid C.

      2009-01-01

      Nanoparticle (NP) size has been shown to significantly effect the biodistribution of targeted and non-targeted NPs in an organ specific manner. Herein we have developed NPs from carboxy-terminated poly (d,l-lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-b-PEG-COOH) polymer and studied the effects of altering the following formulation parameters on the size of NPs, including: 1) polymer concentration, 2) drug loading, 3) water miscibility of solvent, and 4) the ratio of water to solvent. We found that NP mean volumetric size correlates linearly with polymer concentration for NPs between 70 and 250 nm in diameter (linear coefficient = 0.99 for NPs formulated with solvents studied). NPs with desirable size, drug loading, and polydispersity were conjugated to the A10 RNA aptamer (Apt) that binds to the Prostate Specific Membrane Antigen (PSMA), and NP and NP-Apt biodistribution was evaluated in a LNCaP (PSMA+) xenograft mouse model of PCa. The surface functionalization of NPs with the A10 PSMA aptamer significantly enhanced delivery of NPs to tumors vs. equivalent NPs lacking the A10 PSMA aptamer (a 3.77-fold increase at 24 hrs; NP-Apt 0.83% ± 0.21% vs. NP 0.22% ± 0.07% of injected dose per gram of tissue; mean ± s.d., n = 4, p = 0.002). The ability to control NP size together with targeted delivery may result in favorable biodistribution and development of clinically relevant targeted therapies. PMID:17055572

    16. Structural Basis for Induction of Peripheral Neuropathy by Microtubule-Targeting Cancer Drugs.

      Science.gov (United States)

      Smith, Jennifer A; Slusher, Barbara S; Wozniak, Krystyna M; Farah, Mohamed H; Smiyun, Gregoriy; Wilson, Leslie; Feinstein, Stuart; Jordan, Mary Ann

      2016-09-01

      Peripheral neuropathy is a serious, dose-limiting side effect of cancer treatment with microtubule-targeting drugs. Symptoms present in a "stocking-glove" distribution, with longest nerves affected most acutely, suggesting a length-dependent component to the toxicity. Axonal transport of ATP-producing mitochondria along neuronal microtubules from cell body to synapse is crucial to neuronal function. We compared the effects of the drugs paclitaxel and ixabepilone that bind along the lengths of microtubules and the drugs eribulin and vincristine that bind at microtubule ends, on mitochondrial trafficking in cultured human neuronal SK-N-SH cells and on axonal transport in mouse sciatic nerves. Antiproliferative concentrations of paclitaxel and ixabepilone significantly inhibited the anterograde transport velocity of mitochondria in neuronal cells, whereas eribulin and vincristine inhibited transport only at significantly higher concentrations. Confirming these observations, anterogradely transported amyloid precursor protein accumulated in ligated sciatic nerves of control and eribulin-treated mice, but not in paclitaxel-treated mice, indicating that paclitaxel inhibited anterograde axonal transport, whereas eribulin did not. Electron microscopy of sciatic nerves of paclitaxel-treated mice showed reduced organelle accumulation proximal to the ligation consistent with inhibition of anterograde (kinesin based) transport by paclitaxel. In contrast, none of the drugs significantly affected retrograde (dynein based) transport in neuronal cells or mouse nerves. Collectively, these results suggest that paclitaxel and ixabepilone, which bind along the lengths and stabilize microtubules, inhibit kinesin-based axonal transport, but not dynein-based transport, whereas the microtubule-destabilizing drugs, eribulin and vincristine, which bind preferentially to microtubule ends, have significantly less effect on all microtubule-based axonal transp