ACE2-Inhibitory Effects of Bromelain and Ficin in Colon Cancer Cells.

Background and Objectives: Bromelain and ficin are aqueous extracts from fruits of Ananas comosus and Ficus carcia plants, used widely for medical applications. Angiotensin-converting enzyme 2 (ACE2) is a homolog of ACE, degrading Ang II to angiotensin 1-7 and decreasing the cellular concentration of Ang II. Materials and Methods: In this study, we investigated the ACE2-inhibitory, antiproliferative, and apoptosis-inducing effects of ficin and bromelain on caco-2 cells. Results: We found that bromelain and ficin significantly reduced the viability of human colon cancer cells with IC50 value concentrations of 8.8 and 4.2 mg/mL for bromelain after 24 and 48 h treatments, and 8.8 and 4.2 mg/mL for ficin after 24 and 48 h treatments, respectively. The apoptosis of the caco-2 cell line treated with bromelain was 81.04% and 56.70%, observed after 24 and 48 h. Total apoptotic proportions in caco-2 cells treated with ficin after 24 and 48 h were 83.7% and 73.0%. An amount of 1.6 mg/mL of bromelain and ficin treatments on caco-2 cells after 24 h revealed a higher decrease than that of other concentrations in the expression of ACE2 protein. Conclusions: In conclusion, bromelain and ficin can dose-dependently decrease the expression of ACE2 protein in caco-2 cells.

A comprehensive review on methotrexate containing nanoparticles; an appropriate tool for cancer treatment.

For more than seven decades, methotrexate has been used all over the world for treatment of different diseases such as: cancer, autoimmune diseases, and rheumatoid arthritis. Several studies have addressed its formula, efficacy, and delivery methods in recent years. These studies have been focused on the effectiveness of different nanoparticles on drug delivery, delivery of the drug to the target cells, and attenuation of harm to the host cell. Whereas, the main usages of methotrexate are in cancer treatment field, this review provided a brief perspective into using different nanoparticles and their role in the treatment of different cancers.

Design and Characterization of Liposomal Methotrexate and Its Effect on BT-474 Breast Cancer Cell Line.

Background: Breast cancer is the most common type of cancer among women worldwide. Traditional treatments, including chemotherapy, surgery, mastectomy, and radiotherapy, are commonly used. Because of the limitation of the aforementioned methods, novel treatment strategies are needed. Methotrexate is a chemotherapeutic drug, which is commonly used to treat breast cancer. Because of the side effects of the free drug, the liposomal form of the drug is suggested. Methods: Liposomal methotrexate was prepared and the encapsulation efficiency was measured. Moreover, the particle size and the zeta potential were measured. The liposome morphology was confirmed using transmission electron microscopy. The MTT assay was done to examine the cytotoxicity of free and encapsulated methotrexate on BT-474 cell line. The Annexin-V/PI dual staining assay was performed to assess the apoptosis in BT-474 breast cancer cells via the flow cytometry method. Results: The transmission electron microscopy results confirmed the integrated and spherical structure of the nanoparticles. The results of drug release showed that in acidic pH (5.4), more than 90% of the drug was released after 24 hours, which was higher than 2 other pHs. Furthermore, the IC50 value of liposomal methotrexate was determined as 2.15 and 0.82 mg/mL for 24 and 48 hours. The flow cytometry results confirmed that liposomal methotrexate had a greater cytotoxic effect on cancer cells compared with free methotrexate. Conclusion: Because of the advantages of liposomal based nanocarriers, in this study, liposomal methotrexate could be suggested as an appropriate candidate to treat breast cancer.

In silico assessment of human Calprotectin subunits (S100A8/A9) in presence of sodium and calcium ions using Molecular Dynamics simulation approach.

Calprotectin is a heterodimeric protein complex which consists of two subunits including S100A8 and S100A9. This protein has a major role in different inflammatory disease and various types of cancers. In current study we aimed to evaluate the structural and thermodynamic changes of the subunits and the complex in presence of sodium and calcium ions using molecular dynamics (MD) simulation. Therefore, the residue interaction network (RIN) was visualized in Cytoscape program. In next step, to measure the binding free energy, the potential of mean force (PMF) method was performed. Finally, the molecular mechanics Poisson-Boltzmann surface area (MMPBSA) method was applied as an effective tool to calculate the molecular model affinities. The MD simulation results of the subunits represented their structural changes in presence of Ca2+. Moreover, the RIN and Hydrogen bond analysis demonstrated that cluster interactions between Calprotectin subunits in presence of Ca2+ were greater in comparison with Na+. Our findings indicated that the binding free energy of the subunits in presence of Ca2+ was significantly greater than Na+. The results revealed that Ca2+ has the ability to induce structural changes in subunits in comparison with Na+ which lead to create stronger interactions between. Hence, studying the physical characteristics of the human proteins could be considered as a powerful tool in theranostics and drug design purposes.

The bactericidal effect of lysostaphin coupled with liposomal vancomycin as a dual combating system applied directly on methicillin-resistant Staphylococcus aureus infected skin wounds in mice.

BACKGROUND AND AIM: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of surgical infection, and its resistance to numerous conventional antibiotics makes treatment difficult. Although vancomycin is often an effective agent for the initial therapy of MRSA, clinical failure sometimes occurs. Therefore, there is an urgent need to develop better therapies. Here, we prepared some vancomycin-loaded nanoliposomes coupled with anti-staphylococcal protein (lysostaphin) and evaluated their in vitro and in vivo efficacy as a topical MRSA therapy. METHODS: Vancomycin was encapsulated in liposomes, and the coupling of lysostaphin with the surface of liposomes was carried out through cyanuric functional groups. The bactericidal efficacies and a full characterization were evaluated. To define different nanoliposomal-bacterium interactions and their bactericidal effect, flow cytometry was employed. Finally, in vivo, the topical antibacterial activity of each formulation was measured against surgical wound MRSA infection in a mouse model. RESULTS: High encapsulation and conjugation efficiency were achieved for all formulations. All the formulations showed a significant reduction in bacterial counts (p<0.05). The targeted liposomes more effectively suppress bacterial infection in vitro and in vivo relative to equivalent doses of untargeted vancomycin liposome. The flow cytometry results confirmed liposome-bacterium interactions, which increased during the incubation time. The maximum binding rate and the bactericidal effect were significantly higher in targeted liposomes (p<0.05) compared with control liposomes. CONCLUSION: Our data suggest a novel nano-vehicle (lysostaphin-conjugated coupled liposomal vancomycin) which could be used as a great topical antimicrobial construct for treatment of MRSA skin infections.

The bactericidal effect of liposomal vancomycin as a topical combating system against Methicillin-resistant Staphylococcus aureus skin wound infection in mice.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of skin infections and treatment is difficult due to its resistance to the most of antibiotics. Although vancomycin is often considered as an antibacterial agent of choice for the treatment of MRSA, its use is limited because of the high side effects. One solution is using liposomal formulation for local drug delivery. The aim of this study was to determine in vitro and in vivo efficacies of liposomal vancomycin as topical use. Methods: To prepare liposomal vancomycin, the ammonium sulfate gradient using remote loading and freeze-thaw methods was applied. Then, synthesized nanoliposomes were evaluated in terms of particle size, morphology, stability, and encapsulation efficiency. Minimum inhibitory concentration (MIC) of synthesized nanoliposome against MRSA was detected. The cytotoxicity of synthesized nanoliposome was evaluated using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Finally, the topical antibacterial activity of each formulation was tested against MRSA-infected skin wound model in mice. Results: High encapsulation efficiency was achieved for all synthesized nanoliposomes. The results of in vitro and in vivo showed that liposomal vancomycin was more effective than free vancomycin. Also, synthesized nanoliposome showed no cytotoxicity on human epidermoid cell line. Conclusion: The results showed that synthesized nanoliposome could be applied as a great topical antimicrobial construct for treatment of MRSA skin infections.

Immunofluorescent labeling of CD20 tumor marker with quantum dots for rapid and quantitative detection of diffuse large B-cell non-Hodgkin's lymphoma.

Fluorescent semiconductor quantum dots (QDs) are newfound nanocrystal probes which have been used in bioimaging filed in recent years. The purpose of this study is to evaluate the diagnostic value of specific QDs coupled to rituximab monoclonal antibody against CD20 tumor markers for patients with diffuse large B-cell lymphoma (DLBCL). In current study rituximab-conjugated quantum dots (QDs-rituximab) were prepared against CD20 tumor markers for detection of CD20-positive cells (human Raji cell line) using flowcytometry. A total of 27 tumor tissue samples were collected from patients with DLBCL and 27 subjects with negative pathological tests as healthy ones, which stained by QD-rituximab. The detection signals were obtained from QDs using fluorescence microscopy. The flowcytometry results demonstrated a remarkable difference in fluorescent intensity and FL2-H + (CD20-positive cells percentage) between two groups. Both factors were significantly higher in Raji in comparison with K562 cell line (P < 0.05). Lot of green fluorescence signals was observed due to the selectively binding of QD-rituximab to CD20 tumor markers which overexpressed in tumor tissues and a few signals observed on the defined healthy ones. Based on these observations the cut-off point was 46.8 dots and the sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 89.5%, 91.3%, and 100%, respectively (LR+, 9.52; LR-, 0). The QD -rituximab could be beneficial as a bioimaging tool with high sensitivity to provide an accurate molecular imaging technique for identifying CD20 tumor markers for early diagnosis of the patients with DLBCL.