Preparation, optimization and toxicity evaluation of [SPION-PLGA] +/-PEG nanoparticles loaded with gemcitabine as a multifunctional nanoparticle for therapeutic and diagnostic applications

The aim of this study was to develop a novel multifunctional nanoparticle, which encapsulates SPION and Gemcitabine in PLGA +/- PEG to form multifunctional drug delivery system. For this aim, super paramagnetic iron oxide nanoparticles [SPIONs] were simultaneously synthesized and encapsulated with Gemcitabine [Gem] in PLGA +/- PEG copolymers via W/O/W double emulsification method. Optimum size and encapsulation efficiency for radiosensitization, hyperthermia and diagnostic applications were considered and the preparation parameters systematically were investigated and physicochemical characteristics of optimized nanoparticle were studied. Then SPION-PLGA and PLGA-Gem nanoparticles were prepared with the same optimized parameters and the toxicity of these nanoparticles was compared with Gemcitabine in human breast cancer cell line [MCF-7]. The optimum preparation parameters were obtained with Gem/polymer equal to 0.04, SPION/polymer equal to 0.8 and 1% sucrose per 20 mg of polymer. The hydrodynamic diameters of all nanoparticles were under 200 nm. Encapsulation efficiency was adjusted between 13.2% to 16.1% for Gemcitabine and 48.2% to 50.1% for SPION. In-vitro Gemcitabine release kinetics had controlled behavior. Enhancement ratios for PLGA-Gem and SPION-PLGA-Gem at concentration of nanoparticles equal to IC50 of Gemcitabine were 1.53 and 1.89 respectively. The statistical difference was significant [p-value = 0.006 for SPION-PLGA-Gem and p-value = 0.015 for PLGA-Gem compared with Gemcitabine]. In conclusion, we have successfully developed a Gemcitabine loaded super paramagnetic PLGA-Iron Oxide multifunctional drag delivery system. Future work includes in-vitro and in-vivo investigation of radiosensitization and other application of these nanoparticles

Non-biological gene carriers designed for overcoming the major extra- and intracellular hurdles in gene delivery, an updated review

Gene therapy as a modern therapeutic approach has not yet advanced to a globally-approved therapeutic approach. Lack of adequate reliable gene delivery system seems to be one of the major reasons from the pharmaceutical biotechnology point of view. Main obstacles delaying successful application of human gene therapy are presented in this review. The unique advantages of non-biological gene carriers as compared to their biological counterparts make them ideal alternatives for overcoming extra- and intracellular barriers in a more safely manner. We, therefore, highlight the significant contributions in non-biological gene delivery and favorable characteristics of different design attitudes with focus on in vivo approaches. Bypassing the rapid extracellular enzymatic degradation of genetic materials is covered in extracellular segment of this review with emphasis on PEGylated and targeted formulations. The successful approaches to pave the rest of the way from cellular uptake to intracellular transfer and gene expression of unpacked DNA are also discussed. From these approaches, we emphasize more on optimization of cationic-based polymers and dendrimers, developing newly designed membrane-effective components, and adjusting the hydrophilic-hydrophobic balance of the synthesized vectors

Pentoxifylline decreases serum level of adhesion molecules in atherosclerosis patients

Inflammation is involved in development, progression, and complications of atherosclerotic disease. Clinical studies have indicated that the level of monocyte chemoattractant protein 1 [MCP-1], IL-18, and adhesion molecules correlates with the severity of atherosclerosis and can predict future cardiovascular events. Experimental studies have shown pentoxifylline [PTX] reduces these factors in animal models. The purpose of the present pilot study was to evaluate effect of PTX on a group of inflammatory biomarkers in patients with coronary artery disease [CAD]. Forty patients with angiographically documented CAD, who fulfilled inclusion and exclusion criteria, were entered in the double-blind, randomized, pilot clinical study. The patients were randomly given PTX [400 mg three times daily] or placebo [3 tab/day] for 2 months. Serum concentrations of MCP-1, IL-18, intercellular adhesion Molecule 1 [ICAM-1], and vascular cell adhesion molecule 1 [VCAM-1] were measured before and at the end of intervention by enzyme-linked immunosorbant assay. Our study showed that the serum levels of ICAM-1 and VCAM-1 was decreased in the study population after two-month treatment [P<0.05]. Based on the results of our pilot study, administration of PTX in CAD patients significantly decreases adhesion molecules levels

novel label-free cocaine assay based on aptamer-wrapped single-walled carbon nanotubes

This paper describes a selective and sensitive biosensor based on the dissolution and aggregation of aptamer wrapped single-walled carbon nanotubes. We report on the direct detection of aptamer-cocaine interactions, namely between a DNA aptamer and cocaine molecules based on near-infrared absorption at 807. First a DNA aptamer recognizing cocaine was non-covalently immobilized on the surface of single walled carbon nanotubes and consequently dissolution of SWNTs was occurred. Vis-NIR absorption [A[807nm]] of dispersed, soluble aptamer-SWNTs hybrid, before and after incubation with cocaine was measured using a CECIL9000 spectrophotometer. This carbon nanotube setup enabled the reliable monitoring of the interaction of cocaine with its cognate aptamer by aggregation of SWNTs in the presence of cocaine. This assay system provides a mean for the label-free, concentration-dependent, and selective detection of cocaine with an observed detection limit of 49.5 nM

Gene transfer enhancement by alkylcarboxylation of poly[propylenimine]

Among synthetic carriers, dendrimers with the more flexible structure have attracted a great deal of researchers' attention in the field of gene delivery. Followed by the promising results upon hydrophobic modification on polymeric structures in our laboratory, alkylated poly [propylenimine]-based carriers were synthesized by nucleophilic substitution of amines with alkyl moieties and were further characterized for their physicochemical and biological characteristics for plasmid DNA delivery. Although not noticeably effective gene transfer activity for hexanoate- and hexadecanoate- modified series was observed, but alkylation by decanoic acid significantly improved the transfection efficiency of the final constructs up to 60 fold in comparison with unmodified poly[propylenimine] [PPI]. PPI modified by 10-bromodecanoic acid at 50% grafting, showed significantly higher gene expression at c/p ratio of 2 compared to Superfect as positive control. Overall, modification of PPI with 50% primary amines grafting with 10-bromodecanoic acid could increase the transfection efficiency which is occurred at lower c/p ratio when compared to Superfect, i.e. less amount of modified vector is required to exhibit the same efficiency as Superfect. Therefore, the obtained constructs seem to be safer carriers for long-term gene therapy applications

Phototoxicity activity of Psoralea drupacea L. using Atremia salina bioassay system

Phototoxicity is a kind of dermatitis that is activated by exposure to ultraviolet light following the administration of some drugs or natural products. Artemia salina [A. salina] [brine shrimp] has been effectively applied for toxicity testing and is perfect for biological screening of many chemicals for simultaneous evaluation of toxicity and phototoxicity. The objective of this study was to investigate the phototoxic activitiy of the methanolic extract and chloroform and CH3OH/H2O2 fraction of Psoralea drupacea [P. drupacea]. The phototoxic effect of the methanolic extract, chloroform and CH3OH/H2O2 fractions of P. drupacea was evaluated using A. salina bioassay system. Different concentrations of methanolic extract and fractions of P. drupacea were added to the plate of one-day old larvae followed by exposure to UV radiation at 366 nm in three different exposure times [0, 4 and 20 h]. Mortality was determined 24h after the start of the irradiation. The value of LC[50] of P. drupacea methanolic extract and methoxalen as positive control were 0.64 and 3.5x10-4 mg/ml, respectively. P. drupacea methanolic extract and chloroform fraction demonstrated phototoxic activity after 4 h radiation. The result showed that P. drupacea methanolic extract and chloroform fraction have phototoxicity in A. salina bioassay system and their toxic effect is related to phototoxic constituents such as psoralen

Chemical composition, antimicrobial activity and antiviral activity of essential oil of Carum copticum from Iran

Evaluation of therapeutic effects of Carum copticum [C. copticum] has been the subject of several studies in recent years. Thymol the major component of C. copticum is a widely known antimicrobial agent. In this study, the antibacterial and anti viral activities of essential oil of C. copticum fruit were determined. Essential oil of C. copticum was analyzed by means of gas chromatographymass spectrometry [GC-MS]. The antimicrobial activity of the oil was evaluated against six Gram [+/-] bacteria and fungi, using the micro broth dilution technique. Antiviral activity of the essential oil was evaluated using a Bacillus phage CP51. From the ten identified constituents, representing 98.7% of the oil, thymol [72.3%], terpinolene [13.12%] and o-cymene [11.97%] were the major components. It was found that the oil exhibited strong antimicrobial activity against Staphylococcus aureus [S. aureus] and Bacillus subtilis [B. subtilis] [MIC, 0.00025% v/v]. Furthermore, the antiviral activity of the oil was evaluated by plaque reduction assay. The essential oil showed an antiviral activity against phage when phage was pre-incubated with the essential oil prior to its exposure to B. cereus and without any pre-incubation with the phage, suggesting that the oil directly inactivated virus particles

effect of linear PEI on characteristics and transfection efficiency of PEI-based cationic nanoliposomes

The development of efficient and safe carrier system to transfer DNA into cells is essential in non-viral gene therapy. The aim of the present study was to evaluate the effect of linear polyetheneimine [lPEI] [2500 Da] on the physicochemical and biological properties of lipopolyplexes constructed from liposomes and lPEI. Different lipopolymers were synthesized from lPEI and acrylate derivatives. Nanocarriers were composed of the lipids [DOPE, DPPE and DOTAP] and the synthesized lipopolymers. After characterization of the prepared vectors by determination of size and zeta potential, transfection activity was tested in Neuro2A cells. Ethidium bromide and MTT test were used to evaluate the DNA condensation ability and cytotoxicity of vectors, respectively. Vector's size ranged from 95 to 337 nm and they had positive charge. The differences in DNA binding properties of lipopolyplexes were not significant. Among lipids, DOTAP showed better impact on transfection efficiency. The highest transfection activity was achieved by liposomal formulation consist of DOTAP and lipopolymer composed of lPEI and hexyl acrylate. The lipopolyplexes showed minimum cytotoxicity to the cultured cells in vitro. The results of study confirmed that it is possible to improve gene expression using lipopolyplexes

Immunoinhibitory effect of teuclatriol a guaiane sesquiterpene from salvia mirzayanii

Salvia mirzayanii, a native plant to Iran, is shown to have immunomodu-latory effects on lymphocyte proliferation. To identify the bioactive immu-nomodulatory compound [s] present in S. mirzayanii. The crude extract was fractionated to five fractions in two steps using different solvents. The fractions were subjected to bioassay-guided fractionation. All the fractions were tested for bioactivity on human activated-peripheral blood lymphocytes [PBLs] using cell proliferation assay. The methanol fraction [Fr. M] showed the highest inhibitory effect on PBLs compared to other fractions. Fr. M was applied on a gravity column chromatography for further fractionation. Resultant fractions, demonstrated inhibitory effects at higher concentrations. Fr. 4 with an 18.9 +/- 0.2% inhibitory activity at 200 microg/ml and with the highest quantity was applied on preparative TLC plates for further purification. The final purified compound was identified as teuclatriol, a guaiane sesquiterpene, by NMR analysis. This compound showed a significant anti-proliferative effect on human activated-peripheral blood lymphocytes [IC50, 72.8 +/- 5.4 microg/ml]. Teuclatriol was found to be one of the compounds responsible for the immuno inhibitory effect of Salvia mirzayanii. We suggest further studies on teuclatriol, exploring its mechanism of action as an immunomodulatory compound

Inhibition of helicobacter pylori growth in vitro by saffron [Crocus sativus L.]

Anti-Helicobacter pylori effects of saffron [Crocus sativus L., lridacea] and its major constituents, crocin and saftanal, were evaluated. Macerated aqueous and methanol extracts tested against 45 clinical isolates of Helicobacter pylori, using paper disc diffusion method [DDM] on modified egg yolk emulsion agar [EYE agar]. Four antibiotics also tested against all isolates as positive control. Although there were small differences in sensitivity among the isolates tested, but all isolates were susceptible to methanol and aqueous extracts. The minimum inhibitory concentrations [MIC] of methanol extract, crocin and saftanal measured as 677, 26.5 and 16.6 mg/ml, respectively, using agar dilution method. The results showed that high temperature did not have any effect on the activity of extracts, crocin and saftanal. The effect of pH on the activity of methanol extract indicated no significant difference at pH 5 to 8, in comparison with the control. The results indicated that saffion has a moderate anti-Helicobacter activity