Nano-co-delivery of lipophosphoglycan with soluble and autoclaved leishmania antigens into PLGA nanoparticles: Evaluation of in vitro and in vivo immunostimulatory effects against visceral leishmaniasis.

The aim of the present study was to encapsulate lipophosphoglycan molecule (LPG) which is one of the most immunogenic antigens of Leishmania parasites into PLGA nanoparticles with autoclaved or soluble leishmanial antigens, characterize synthetized nanoparticles with different methods and evaluate their in vitro/in vivo immunostimulatory activities to develop new vaccine candidates. PLGA nanoparticles including LPG and autoclaved leishmania antigen (ALA) or soluble leishmania antigen (ALA) were synthetized by double emulsion solvent evaporation method. The synthetized nanoparticles were characterized by SEM and Zeta-sizer instruments for determination of size, zeta potentials and polydispersity index (PDI) values. The antigen release profiles and encapsulation efficiencies were determined by UV-Vis spectroscopy. Griess reaction and ELISA tests were used for measurements of produced nitric oxide (NO) and cytokine levels of macrophages and splenocytes treated with nanoparticles. For determination of protective effects of nanoparticles, parasite reduction in livers and spleens of immunized mice were calculated by LDU values post-infection. According to results, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs possessed the sizes of 253 and 307 nm respectively. Antigen-loaded nanoparticles elevated the released NO amounts from macrophages for 14 and 18-folds in contrast to control. Furthermore, synthetized nanoparticles significantly triggered macrophages to produce excessive levels of IFN-γ and IL-12 cytokines. Besides it was detected that vaccination of mice with (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs elicited approximately 80% protection from Visceral Leishmaniasis. Furthermore, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs lead to 10 to 14-folds increase in secreted Th1 cytokine levels from splenocytes than control demonstrating abundantly stimulation of T cell response following to vaccination with nano-vaccine formulations. These results reveal that both (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs have excellent immunostimulatory activities and they are promising nanovaccine formulations for the prevention of leishmaniasis in near future.

A nanotechnology-based new approach in the treatment of breast cancer: Biosynthesized silver nanoparticles using Cuminum cyminum L. seed extract.

The present study reports the anticancer activities of Cuminum cyminum L. (Cumin) seed extract, chemically synthetized silver nanoparticles (AgNPs) and biosynthesized silver nanoparticles (Bio-AgNPs) from Cumin seeds on human breast adenocarcinoma cell line (MCF-7) and human breast adenocarcinoma metastatic cell line (AU565). The synthetized nanoparticles were characterized by dynamic light scattering (DLS), UV-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The cytotoxic and anticancer effects of AgNPs and Bio-AgNPs were determined by MTT assay. According to the cytotoxicity analysis, Bio-AgNPs appears to be less toxic against J774 macrophage cells than AgNPs since IC50 values were measured as 0.75 and 1.25 µg/ml for AgNPs and Bio-AgNPs, respectively. On the other hand, Bio-AgNPs demonstrated significant inhibitory effects on human breast cancer cells at non-toxic concentrations such as 0.25 and 0.5 µg/ml. However, at increased concentrations, the lethal effects of AgNPs on breast cancer cells were higher than Bio-AgNPs. When cytotoxic and anticancer characteristics of Cumin extract were investigated, it was established that it did not show any inhibitory effect on J774 cells, while killing the half of MCF-7 cells at investigated concentrations. Interestingly, Cumin extract gave rise to no inhibitory effects against AU565 cells. On the other hand, AgNPs and Bio-AgNPs exhibited considerable anticancer activities on both cell lines. The inhibition percentages of AgNPs on MCF-7 and AU565 cell lines were respectively evaluated as 95% and 97% at the highest concentrations applied (12.5 µg/ml). Similarly, we determined that 87.5% and 96% of MCF-7 and AU565 cells were respectively inhibited when they were exposed to the highest concentrations of Bio-AgNPs. Considering relatively toxic-free features of Bio-AgNPs prepared from Cuminum cyminum L. seed extracts, it can be thought that this formulation will be a pioneer in development of nanotechnology-based new anticancer drug for the treatment of breast cancer in near future.

Investigation of antileshmanial activities of Cuminum cyminum based green silver nanoparticles on L. tropica promastigotes and amastigotes in vitro.

Leishmaniasis is one of the most important parasitic diseases, which is caused by Leishmania species. Nowadays; although pentavalent antimonials are used as the basic treatment option for Cutaneous Leishmaniasis, high cost, toxicity and resistance of the parasites to the medication over time are some important limitations causing several problems in the treatment. In recent years, the progress in the field of green nanotechnology provides the development of green nanoparticle-based treatment methods for Cutaneous Leishmaniasis. The importance of green nanoparticles has gradually increased due to their special reductive, stabilizing, antioxidant and non-toxic properties. Although there are many studies based on green nanoparticles against Leishmania parasites, we have not found any research about antileishmanial activities of biosynthesized silver nanoparticles (Bio-AgNPs) using Cuminum cyminum L (Cumin) seed extract. Therefore for the first time in this study in vitro antileishmanial effects of Bio-AgNPs prepared from Cumin seed extract were examined on L. tropica promastigote and amastigote forms and their efficacies were compared with chemically synthetized AgNPs. During the experiments, antileishmanial effects of synthetized nanoparticles were determined on both promastigote and amastigote forms of Leishmania parasites by detecting different parameters such as proliferation, infection index and produced nitric oxide (NO) amounts from macrophages. According to the results, it was shown that Bio-AgNPs and AgNPs excessively inhibited L. tropica promastigotes and amastigotes by significantly decreasing proliferation rates of promastigotes and metabolic activities of amastigotes, as well. Moreover, infection index rates of macrophages revealed remarkable anti-amastigote performances of Bio-AgNPs. Besides, Bio-AgNPs stimulated macrophages to release NO to kill Leishmania parasites. Consequently, for the first time, Bio-AgNPs were found to be more effective on both forms of Leishmania parasites than AgNPs. Obtained results indicated high antileishmanial potential of green nanoparticles on L. tropica parasites, causative agents of Cutaneous Leishmaniasis. Thus, obtained results demonstrated that green nanoparticles can lead to the development of new, safer, stable and more effective antileishmanial formulations against Cutaneous Leishmaniasis.

Current Approaches in Treatment of Diabetic Retinopathy and Future Perspectives.

Diabetes mellitus (DM) is a metabolic disease, which is the most common cause of low vision in developing countries and affects almost all systems of the body. In view of the increase in DM prevalence in the world, it would not be a surprise that diabetic retinopathy (DR) and other vascular complications related to diabetes become a serious public health problem. Currently, vascular endothelial growth factor, laser photocoagulation, and intravitreal steroids are the mainstays for DR treatment, but the efficacy of these treatment strategies remains insufficient. Therefore, new treatment modalities for DR have been developed, such as stem cell therapies, extracellular vesicular system, and nanodrug delivery systems. Although there have been several reviews in the literature on the treatment of DR, we have not confronted any review that has the titles of all these topics. With this review, we aim to present the pathophysiology of DR and to review the current and promising new treatment methods based on stem cells, extracellular vesicular system, and nanodrug delivery systems for the future of DR management.

Large-scale cultivation of Leishmania infantum promastigotes in stirred bioreactor.

BACKGROUND & OBJECTIVES: Bioreactors are practical tools that are used for economical, time-conserving and large-scale production of biomass from cell cultivation. They provide optimal environmental conditions such as pH and temperature required for obtaining maximum amounts of biomass. However, there is no evidence in the literature on the large-scale cultivation of Leishmania infantum parasites in the bioreactor. Therefore, the present study was undertaken to develop a new approach for obtaining L. infantum biomass by using pH and temperature controllable stirred bioreactor and to compare parasitic growth kinetics with classical method within erlenmeyers. METHODS: In order to obtain parasite biomass, a newly developed pH and temperature controlled stirred bioreactor was used and its efficacy was compared with a graduated classical scale-up method. Growth kinetics of parasites within erlenmeyers and bioreactors were determined by evaluating promastigote numbers using haemocytometer. The graduated scale enlargement of culture was followed by T25 flask, T75 flask, and 1 L erlenmeyer, respectively. RESULTS: Obtained results showed a 10-fold increase in the number of promastigotes within the conventional culture performed in 700 ml medium, while parasite numbers increased approximately 15 times due to initial inoculation amounts in the bioreactor culture performed in the 3.5 l medium. Thus, there was 7.5 times more biomass collection in bioreactor compared to classical method. INTERPRETATION & CONCLUSION: It is postulated that constant culture pH and temperature in the bioreactor extends cultivation time. This could lead to significant increase in parasite numbers. Hence, pH and temperature controllable bioreactors provided acquisition of sufficient amounts of biomass in contrast to classical methods. Therefore, this type of bioreactors may substitute classical culture methods in the production of antigenic molecules for vaccine development.

Current aspects in treatment of breast cancer based of nanodrug delivery systems and future prospects.

Breast cancer is one of the most common diseases worldwide. The risk of getting this disease in female is 30% and the mortality rate is 14%. The breast cancer treatment is based on surgery, chemotherapy and radiotherapy. However, an effective treatment method has not been developed. The main cause of failure in the treatment is cancer stem cells metastasis and chemo-resistance. The use of nanocarrier systems against breast cancer stem cells has great importance. Not only advantages of polymeric drug delivery systems are increasing the stability and reduce the side effects of drugs, but also they have disadvantages such as biocompatibility and long-term potential safety. However, in recent years, studies on exosomes provide several advantages. Exosomes usage as nanocarrier do not cause immunological reactions also the drug effectively transport into the cytosol of targeted cell and have more stability characteristics. Although there are studies about various nanocarrier systems in literature against breast cancer but in general, we have not found any review that brings them together and develops a systematic approach to solving the problem. This review mentions prospective new strategies based on various nanocarrier systems and emphasize the importance of exosome based on drug delivery systems in the treatment of breast cancer.