Application of dextran-coated iron oxide nanoparticles in enhancing the radiosensitivity of cancerous cells in radiotherapy with high-energy electron beams

Purpose: Nowadays, cancer is one of the most important causes of morbidity and mortality in the world. The ideal aim of radiotherapy is delivering a lethal radiation dose to tumor cells while minimizing radiation exposure to healthy tissues around the tumor. One way to increase the dose in the tumor cells is the use of high-atomic number nanoparticles as radiosensitizer agents in these cells. The aim of this in vitro study was investigating the radiosensitization enhancement potential of the dextran-coated iron oxide nanoparticles (IONPs) on HeLa and MCF-7 cell lines in irradiations with high-energy electron beams. Materials and Methods: In this in vitro study, the cytotoxicity level of dextran-coated IONPs at different concentrations (10, 40, and 80 μg/ml) was assessed on HeLa and MCF-7 cell lines. To evaluate the radiosensitivity effect, the nanoparticles were incubated with the cells at different concentrations for 24 h and afterward irradiated with different doses (0, 2, 4, 6, and 8 Gy) of 6 and 12 MeV electron beams. The cells survival fractions were obtained by the methylthiazoletetrazolium assay. Results: Toxicity results of the nanoparticles at 10 and 40 μg/ml concentrations showed no significant cytotoxicity effect. The cells survival rates in groups receiving radiation in the absence and presence of IONPs showed a significant difference. The radiosensitivity enhancement induced by the nanoparticles in MCF-7 cell line was more than it in HeLa cell line. The average of radiosensitization enhancement factor at 10, 40, and 80 μg/ml concentrations and under 6 MeV irradiations obtained as 1.13, 1.19, 1.25, and 1.26, 1.28, 1.29 for HeLa, and MCF-7 cells, respectively. When 12 MeV electron beams were carried out, the values of 1.17, 1.26, 1.32, and 1.29, 1.32, 1.35 were obtained for the cells at the mentioned concentrations, respectively. Furthermore, the significant differences were observed in radiosensitization enhancement between 6 and 12 MeV electron beams irradiations. Conclusion: Use of dextran-coated IONPs can increase radiosensitivity and consequently at a given absorbed dose more cell killing will occur in cancerous cells. In other words, these nanoparticles can improve the efficiency of electron therapy

Antioxidant and cytotoxic properties of protein hydrolysates obtained from enzymatic hydrolysis of Klunzinger's mullet (Liza klunzingeri) muscle

Today, consumers are looking for functional foods that promote health and prevent certain diseases in addition to provide nutritional requirements. This study aimed to evaluate the antioxidant and cytotoxic properties of Liza klunzingeri protein hydrolysates. Fish protein hydrolysates (FPHs) were prepared from L. klunzingeri muscle using enzymatic hydrolysis with papain at enzyme/substrate ratios of 1:25 and 1:50 for 45, 90 and 180 min. The antioxidant activities of the FPHs were investigated through five antioxidant assays. The cytotoxic effects on 4T1 carcinoma cell line were also evaluated. The amino acid composition and molecular weight distribution of the hydrolysate with the highest antioxidant activity were determined by HPLC. All six FPHs exhibited good scavenging activity on ABTS (IC50=0.60-0.12 mg/mL), DPPH (IC50= 3.18-2.08 mg/mL), and hydroxyl (IC50=4.13-2.07 mg/mL) radicals. They also showed moderate Fe+2 chelating capacity (IC50=2.12-12.60 mg/mL) and relatively poor ferric reducing activity (absorbance at 70 nm= 0.01-0.15, 5 mg/mL). In addition, all hydrolysates showed cytotoxic activities against the 4T1 cells (IC50=1.62-2.61 mg/mL). 94.6% of peptide in hydrolysate with the highest antioxidant activity had molecular weight less than 1,000 Da. L. klunzingeri protein hydrolysates show significant antioxidant and anticancer activities in vitro and are suggested to be used in animal studies.

Use Carum copticum essential oil for controlling the Listeria monocytogenes growth in fish model system

This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 ºC for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths.