Legionella Pneumophila and Dendrimers-Mediated Antisense Therapy

Delivery of doxorubicin by Fe3O4 nanoparticles, reduces multidrug resistance gene expression in ovarian cancer cells

BACKGROUND

Ovarian cancer is one of the most common malignancy in women with significant mortality rate due to the resistance to chemotherapy drugs. Doxorubicin (DOX) is a chemotropic agent in ovarian cancer treatment. Overexpression of multidrug resistance (MDR) genes, such as ABCB1, in cancer cells after chemotherapy is one of main problems in clinical applications. Here we have compared the efficiency of doxorubicin-loaded (NIPAAM-DMAEMA) Fe3O4 nanocomposite (DOX-NANO) against DOX on ABCB1(MDR1) gene expression in the ovarian cancer cell line.

MATERIALS AND METHODS

The cell viability of SKOV-3 cells were evaluated by MTT assay. Real Time PCR was used to measure the expression level of MDR1. MTT data were normalized in 10 different attribute weighting models, also to reveal the interaction between DOX, ABCB1, and ovarian cancer genes, Pathway Studio Database (Elsevier) was used.

RESULTS

Cell viability of SKOV-3cells was significantly decreased after 24, 48 and 72 hours (P < 0.0001) of either DOX with IC50 22.38, 0.61 and 0.072 µg/ml or DOX-NANO treatment with IC50 11.54, 1.01, 0.0126 µg/ ml respectively.

TREATMENT

Notable decrease in the expression of MDR gene, ABCB1, was observed 48 hours after treatment with DOX-NANO (P < 0.0001) with 26 % in the assessed with control group. Meta-analysis showed the concentration of 10 μg/ml variables was the second most significant feature, whereas the concentration of 0.01 μg/ml recognized the lowest weights. Also, LGALS3 is an extra cellular receptor with upregulation in ovarian cancer that interacts with ABCB1.

CONCLUSION

Our findings highlight the beneficial effects of DOX delivery in ovarian cancer cells by nanocomposite as efficient drug delivery method. DOX-NANO is a promising therapeutic reagent to overcome chemotherapy resistance in ovarian cancer.

Sulfoglycodendron Antivirals with Scalable Architectures and Activities

Many viruses initiate their cell-entry by binding their multisubunit receptors to human heparan sulfate proteoglycans (HSPG) and other molecular components present on cellular membranes. These viral interactions could be blocked and the whole viruses could be eliminated by suitable HSPG-mimetics providing multivalent binding to viral protein receptors. Here, large sulfoglycodendron HSPG-mimetics of different topologies, structures, and sizes were designed to this purpose. Atomistic molecular dynamics simulations were used to examine the ability of these broad-spectrum antivirals to block multiprotein HSPG-receptors in HIV, SARS-CoV-2, HPV, and dengue viruses. To characterize the inhibitory potential of these mimetics, their binding to individual and multiple protein receptors was examined. In particular, vectorial distributions of binding energies between the mimetics and viral protein receptors were introduced and calculated along the simulated trajectories. Space-dependent residual analysis of the mimetic-receptor binding was also performed. This analysis revealed the detailed nature of binding between these antivirals and viral protein receptors and provided evidence that large inhibitors with multivalent binding might act like a molecular glue initiating the self-assembly of protein receptors in enveloped viruses.

Sulfoglycodendron Antivirals with Scalable Architectures and Activities

Many viruses initiate their cell-entry by binding their multi-protein receptors to human heparan sulfate proteoglycans (HSPG) and other molecular components present on cellular membranes. These viral interactions could be blocked and the whole viruses could be eliminated by suitable HSPG-mimetics providing multivalent binding to viral protein receptors. Here, large sulfoglycodendron HSPG-mimetics of different topologies, structures, and sizes were designed to this purpose. Atomistic molecular dynamics simulations were used to examine the ability of these broad-spectrum antivirals to block multi-protein HSPG-receptors in HIV, SARS-CoV-2, HPV, and dengue viruses. To characterize the inhibitory potential of these mimetics, their binding to individual and multiple protein receptors was examined. In particular, vectorial distributions of binding energies between the mimetics and viral protein receptors were introduced and calculated along the simulated trajectories. Space-dependent residual analysis of the mimetic-receptor binding was also performed. This analysis revealed detail nature of binding between these antivirals and viral protein receptors, and provided evidence that large inhibitors with multivalent binding might act like a molecular glue initiating the self-assembly of protein receptors in enveloped viruses.

Overview of the Clinical and Molecular Features of Legionella Pneumophila: Focus on Novel Surveillance and Diagnostic Strategies

Legionella pneumophila (L. pneumophila) is one of the most threatening nosocomial pathogens. The implementation of novel and more effective surveillance and diagnostic strategies is mandatory to prevent the occurrence of legionellosis outbreaks in hospital environments. On these bases, the present review is aimed to describe the main clinical and molecular features of L. pneumophila focusing attention on the latest findings on drug resistance mechanisms. In addition, a detailed description of the current guidelines for the disinfection and surveillance of the water systems is also provided. Finally, the diagnostic strategies available for the detection of Legionella spp. were critically reviewed, paying the attention to the description of the culture, serological and molecular methods as well as on the novel high-sensitive nucleic acid amplification systems, such as droplet digital PCR.

Polymeric Nanomaterials for Efficient Delivery of Antimicrobial Agents

Bacterial infections have threatened the lives of human beings for thousands of years either as major diseases or complications. The elimination of bacterial infections has always occupied a pivotal position in our history. For a long period of time, people were devoted to finding natural antimicrobial agents such as antimicrobial peptides (AMPs), antibiotics and silver ions or synthetic active antimicrobial substances including antimicrobial peptoids, metal oxides and polymers to combat bacterial infections. However, with the emergence of multidrug resistance (MDR), bacterial infection has become one of the most urgent problems worldwide. The efficient delivery of antimicrobial agents to the site of infection precisely is a promising strategy for reducing bacterial resistance. Polymeric nanomaterials have been widely studied as carriers for constructing antimicrobial agent delivery systems and have shown advantages including high biocompatibility, sustained release, targeting and improved bioavailability. In this review, we will highlight recent advances in highly efficient delivery of antimicrobial agents by polymeric nanomaterials such as micelles, vesicles, dendrimers, nanogels, nanofibers and so forth. The biomedical applications of polymeric nanomaterial-based delivery systems in combating MDR bacteria, anti-biofilms, wound healing, tissue engineering and anticancer are demonstrated. Moreover, conclusions and future perspectives are also proposed.

Newer Methods Drive Recent Insights into Rab GTPase Biology: An Overview

The conserved Ypt/Rab GTPases regulate all major intracellular protein traffic pathways, including secretion, endocytosis and autophagy. These GTPases undergo distinct changes in conformation between their GTP- and GDP-bound forms and cycle between the cytoplasm and membranes with the aid of their upstream regulators. When activated on the membrane in the GTP-bound form, they recruit their downstream effectors, which include components of vesicular transport. Progress in the past 5 years regarding mechanisms of Rab action, functions, and the effects of disruption of these functions on the well-being of cells and organisms has been propelled by advances in methodologies in molecular and cellular biology. Here, we highlight methods used recently to analyze regulation, localization, interactions, and function of Rab GTPases and their roles in human disease. We discuss contributions of these methods to new insights into Rabs, as well as their future use in addressing open questions in the field of Rab biology.

Loop-mediated amplification as promising on-site detection approach for Legionella pneumophila and Legionella spp

Recently Legionella pneumophila is the main causative waterborne organism of severe respiratory infections. Additionally, other Legionella species are documented as human pathogens. In our work, we describe a rapid detection method which combines two advantages for sensitive and specific detection of the genus Legionella: the fast isothermal amplification method "Loop-mediated isothermal AMPlification" (LAMP), and a colorimetric detection method using the metal indicator hydroxynaphtol blue (HBN) which allows to determine an optical signal with a simple readout (with the naked eye). Moreover, we present two approaches for minimizing the assay volume using a stationary microchip LAMP and droplet digital-based LAMP (ddLAMP) as promising highly sensitive setups.

Dendrimer-Enabled Therapeutic Antisense Delivery Systems as Innovation in Medicine

Antisense oligonucleotide (AON)-based therapies concern the treatment for genetic disorders or infections such as a range of neurodegenerative and neuromuscular diseases and have shown benefits in animal models and patients. Nevertheless, successes in the clinic are still strongly limited by unfavorable biodistribution and poor cellular uptake of AONs. Dendrimer macromolecules are synthetically accessible and consist of a core with repeated iterations (named branches) surrounding this core, and on the periphery functional groups which can be modified for ligand attachment. The generations of these branched nanoparticles are based on the number of branches emanating from the core with layered architectures. Dendrimers show promise in several biomedical applications based on their tunable surface modifications allowing the adjustment of their in vivo behavior related to biocompatibility and pharmacokinetic parameters. Dendrimers can be used as nanocarriers of various types of drugs including AONs or nanodrugs. As nanocarriers, polycationic dendrimers can complex multiple negatively charged DNA oligonucleotides on their surface and form stable complexes to promote internalization into the cells based on a good cell membrane affinity. These nanocarriers complexing antisense oligonucleotides must be stable enough to reach the cellular target, but with adequate in vivo global clearance, and have good pharmacokinetic (PK) and pharmacodynamic (PD) profiles. This Review was designed to analyze the development of AONs carried by polycationic and polyanionic (few example) dendrimers. This Review strongly supports the idea that dendrimers, with adequate modulation of their terminal groups, could be used to carry AONs in cells.

Enhancement of anticancer activity by silibinin and paclitaxel combination on the ovarian cancer

BACKGROUND

Ovarian carcinoma is the most lethal cancer among all gynaecological malignancies. One of the most chemotherapy drugs used for ovarian cancer is paclitaxel which induces apoptosis. Paclitaxel has been used for many years. Similar to the most cancers this responds to chemotherapy initially but in a long run, drug resistance happens which fails the treatment procedure. Combination of chemotherapy drugs has been suggested to deal with this issue. Silibinin, a plant extraction, has been used from ancient time in traditional medicine and identified to have powerful antioxidant activity.

AIM

The aim of this study was to examine the effect of paclitaxel and silibinin combination on SKOV-3 cancer cell line.

MATERIALS AND METHODS

The human epithelial ovarian cancer cell line, SKOV-3, was cultured and treated with paclitaxel, silibinin and paclitaxel plus silibinin for 48 hours. MTT assay was carried out to determine cell viability. For apoptotic process, we used real-time PCR to study P53 and P21 genes expression after drug treatment and network analysis was performed using Pathway Studio web tool (Elsevier).

RESULTS

Cell growth was inhibited considerably (p < .05) by combination of paclitaxel and silibinin after 48 hours of treatment. Also silibinin and paclitaxel combination induced apoptosis in SKOV-3 cells. Expression analysis by real-time PCR showed the significant up-regulation of two tumour suppressor genes, P53 and P21 in response to combination of silibinin and paclitaxel. In addition, computational network analysis demonstrated the crosstalk between paclitaxel, silibinin and ovarian cancer.

CONCLUSIONS

Our results showed that combination of chemotherapy drugs of silibinin and paclitaxel can be more efficient in treatment of ovarian cancer cells.