Alginate microcapsules as nutrient suppliers: an in vitro study

Objective: Alginate, known as a group of anionic polysaccharides extracted from seaweeds, has attracted the attention of researchers because of its biocompatibility and degradability properties. Alginate has shown beneficial effects on wound healing as it has similar function as extracellular matrix. Alginate microcapsules [AM] that are used in tissue engineering as well as Dulbecco's modified Eagle's medium [DMEM] contain nutrients required for cell viability. The purpose of this research was introducing AM in medium and nutrient reagent cells and making a comparison with control group cells that have been normally cultured in long term

Materials and Methods: In this experimental study, AM were shaped in distilled water, it was dropped at 5 mL/hours through a flat 25G5/8 sterile needle into a crosslinking bath containing 0.1 M calcium chloride to produce calcium alginate microspheres. Then, the size of microcapsules [300-350 microm] were confirmed by Scanning Electron Microscopy [SEM] images after the filtration for selection of the best size. Next, DMEM was injected into AM. Afterward, adipose- derived mesenchymal stem cells [ADSCs] and Ringer's serum were added. Then, MTT and DAPI assays were used for cell viability and nucleus staining, respectively. Also, morphology of microcapsules was determined under invert microscopy

Results: Evaluation of the cells performed for spatial media/microcapsules at the volume of 40 microl, showed ADSCs after 1-day cell culture. Also, MTT assay results showed a significant difference in the viability of sustained-release media injected to microcapsules [P<0.05]. DAPI staining revealed living cells on the microcapsules after 1 to 7-day cell culture

Conclusion: According to the results, AM had a positive effect on cell viability in scaffolds and tissue engineering and provide nutrients needed in cell therapy

Preparation and evaluation of rifampicin and co-trimoxazoleloaded nanocarrier against brucella melitensis infection

Background: Brucellosis or Malta fever is a contagious infection common between human and domestic animals. Many antibiotics are used for brucellosis treatment, but they are not efficient and put heavy burden on society. Co-trimoxazole and rifampicin are two candidates for brucellosis treatment. In this study, we aimed to enhance the efficacy of these antibiotics using designed nanoparticles

Methods: Different concentrations of cotrimoxazole and rifampicin were used for loading onto a nanostructure of synthesized monomethoxy poly[ethylene glycol]-oleate [mPEG-OA]. The solubility, cytotoxicity, and efficacy of these nano-packed antibiotics on Brucella-infected murine phagocytic cells were examined, as compared with free antibiotics. Then the release nanoparticles was increased approximately 3.5 and 1.5fold, respectively, which is considerable in comparison with free insoluble ones

Results: Despite acceptable loading percentage, the application of co-trimoxazole-loaded nanoparticle on Brucella-infected J774A.1 murine macrophage-like cells did not lead to reduction in the number of bacteria; however, the efficacy of rifampicin on Brucella-infected murine phagocytic cells enhanced

Conclusion: In the current study, the efficacy of rifampicin on reducing the number of Brucella melitensis increased by the novel synthesized nanostructure. In contrast, since co-trimoxazole efficacy did not enhance by loading onto nanoparticles, the co-trimoxazole inefficiency is most likely not due to its low penetration or insolubility, and probably there are other factors that remain to be clarified in the future investigations

[Study of loading, cytotoxicity, uptake, and release of curcumin from a novel gemini surfactant nanocarrier]

Objective: Numerous researches have been conducted to comprehend the anti-cancer effects of curcumin [Cu]. Although the anti-proliferative properties of Cu on cancerous cells is known, the clinical application of this gold substrate is limited. This limitation is mostly due to low solubility, inefficient bioavailability, rapid metabolism, and improper uptake. In this study, we have synthesized a novel biodegradable gemini surfactant [Gs], after which the curcumin [Cu] molecules were encapsulated within the polymer to overcome its physicochemical limitations

Methods: We prepared Gs-Cu nanoparticles by the nanoprecipitation method. Size and polydispersity index of the nanoparticles were determined by the dynamic light scattering [DLS] technique. The release profile of Cu from the polymer matrix was studied, and the MTT assay and cellular uptake of Gs-Cu on MDA-MB-231 cells were investigated in vitro

Results: The Gs polymer had the capability to form polymersomes in an aqueous solution; a narrow size distribution was obtained [PDI=0.3]. The encapsulation efficiency approximated 87%. We observed a sustained release profile due to incorporation of Cu into the polymer matrix. The Gs-Cu complex showed more cytotoxicity compared to free Cu because of the higher rate of cellular internalization

Conclusions: The data indicate that Gs polymersomes can be regarded as nanocarriers for hydrophobic curcumin molecules

[Design and synthesis of a novel dendrosome and a PEGylated PAMAM dendrimer nanocarrier to improve the anticancer effect of turmeric [curcuma longa] curcumin]

In recent decades, the anticancer effect of curcumin has been proven by several studies. Curcumin affects multiple cell signaling pathways and prevents cell proliferation, invasion, metastasis and angiogenesis. However, the aqueous solubility of curcumin and its bioavailability are very low which restricts its anticancer properties. In this research, we have synthesized a monomethoxy poly [ethylene glycol]-Oleate [mPEGOA] di-block copolymer and used a surface PEGylated poly [amidoamine] [PAMAM] dendrimer to improve bioavailability of curcumin in cancer cells. The critical micelle concentration [CMC] of mPEG-OA, drug loading efficiencies, and cytotoxicity in the human glioblastoma cell line [U87MG] of all the prepared nanodevices were thoroughly investigated. Atomic force microscopy [AFM] and dynamic light scattering [DLS] studies have shown that mPEG-OA have two common nanostructures, micelles and polymerosomes. mPEG-OA micelles had a very low CMC [0.03 g/l]. The IC50 of free curcumin [0.01 methanol solution] was 48 microM, curcumin-loaded mPEG-OA was 24 microM, and curcumin-loaded PAMAM dendrimer was 13 microM. Moreover, the PEGylated PAMAM was non-cytotoxic. The results indicated that by using these nanocarriers, the bioavailability of curcumin significantly increased compared to free curcumin. Overall, this research revealed that these curcumin nanocarriers could be considered as appropriate drug delivery systems for curcumin delivery in cancer cells

[Dendrosomal curcumin induced apoptosis by suppression of pluripotency genes in 5637 bladder cancer cells]

The anti-cancer properties of curcumin, a poliphenol extract from the rhizome of curry, has been confirmed by many investigators. However, low levels of uptake, tissue distribution and rapid metabolism has limited its application as an anti-cancer drug. This study is aimed at increasing curcumin's water solubility due to a biodegradable, neutral and non-toxic micellar nano-carrier called dendrosome. This study intends to evaluate the role of dendrosomal-curcumin [DNC] in bladder cancer cell growth. We performed the MTT assay, flow cytometry and Annexin V-FLUOS [as an apoptosis detection kit] to evaluate cell death. The genetic mechanism of DNC-induced apoptosis was accomplished by a study of the relative expressions of OCT4A, OCT4B1, SOX-2 and Nanog using real-time PCR. DNC-induced cell death complied with a time and dose-dependent paradigm in the 5637 cell line. Cell cycle analysis revealed that the number of cells increased in pre-G1 and gradually decreased in G1 and S phases. This showed the inhibitory property of dendrosomal-curcumin on DNA synthesis. Data from real-time PCR determined that expressions of OCT4A, OCT4B1, SOX-2 and Nanog could be related to 5637 cancer cell growth. Dendrosomal-curcumin significantly suppressed mRNA expression of the above mentioned genes [p<0.01]. The data showed that DNC induced apoptosis by suppression of pluripotency genes in 5637 bladder cancer cells, which confirmed the useful characteristic of nano-drug in bladder cancer therapy.

[Evaluation of the antimicrobial effects of dental disinfectant solutions with Nano silver on oral current bacteria]

Background and Aim: Equipments and surfaces in dental clinics and centers are always in risk of contamination. When there is no possibility of sterilizing them, fast acting disinfecting agents are used. In this study, antibacterial effect of a new disinfecting solution, named Nanex,against streptococcus mutans and pseudomonas aeroginosa was compared with pure Nano silver solution and Deconex 53 plus

Materials and methods: In this experimental study, in order to determine the effective antibacterial concentration , serial dilution technique ,evaluation of [MIC] and [MBC] were used. Finally bacterial growth was assessed

Results: The # 4 solution [containing 100 ppm Nano silver and 2% Deconex] showed the least MIC and MBC for streptococcus mutans. The # 7 solution [containing 133 ppm Nano silver and 1% Deconex] showed the least MIC and MBC for psuedomonas aerogenosa

Conclusion: Thus, antibacterial effect of Nanex solution was more potent and effective than pure solution of nano silver and deconex