Toxicity effect of silver nanoparticles on mice liver primary cell culture and HepG2 cell line

Nano-silver [AgNP] has biological properties which are significant for consumer products, food technology, textiles and medical applications [e.g. wound care products, implantable medical devices, in diagnosis, drug delivery, and imaging]. For their antibacterial activity, silver nanoparticles are largely used in various commercially available products. Thus, the use of nano-silver is becoming more and more widespread in medicine. In this study we investigated the cytotoxic effects of AgNPs on liver primary cells of mice, as well as the human liver HepG[2] cell. Cell viability was examined with MTT assay after HepG[2] cells exposure to AgNPs at 1, 2, 3, 4, 5, 7.5, 10 ppm compared to mice primary liver cells at 1, 10, 50, 100, 150, 200, 400 ppm for 24h. AgNPs caused a concentration-dependent decrease of cell viability in both cells. IC50 value of 2.764 ppm [Micro g/ml] was calculated in HepG[2] cell line and IC[50] value of 121.7 ppm [Micro g/ml] was calculated in primary liver cells of mice. The results of this experiment indicated that silver nanoparticles had cytotoxic effects on HepG[2] cell line and primary liver cells of mice. The results illustrated that nano-silver had 44 times stronger inhibitory effect on the growth of cancerous cells [HepG[2] cell line] compared to the normal cells [primary liver cells of mice]. which might further justify AgNPs as a cytotoxic agents and a potential anticancer candidate which needs further studies in this regard

Detection of genetically modi?ed maize in processed foods Sold commercially in Iran by qualitative PCR

Detection of genetically modified organisms [GMOs] in food is an important issue for all the subjects involved in food control and customer's right. Due to the increasing number of GMOs imported to Iran during the past few years, it has become necessary to screen the products in order to determine the identity of the consumed daily foodstuffs. In this study, following the extraction of genomic DNA from processed foods sold commercially in Iran, qualitative PCR was performed to detect genetically modified maize. The recombinant DNA target sequences were detected with primers highly specific for each investigated transgene such as CaMV35s gene, Bt-11, MON810 and Bt-176 separately. Based on the gel electrophoresis results, Bt-11 and MON810 events were detected in some maize samples, while, in none of them Bt-176 modified gene was detected. For the first time, the results demonstrate the presence of genetically modified maize in Iranian food products, reinforcing the need for the development of labeling system and valid quantitative methods in routine analyses

Effect of topical application of silymarin [silybum marianum] on excision wound healing in albino rats

Silymarin, an extract from Silybum marianum, has been shown to have antioxidant properties. However, there is no scientific report on wound healing activity of the silymarin. The purpose of this study was to evaluate the effect of topical administration of silymarin on excision wound healing in rats. Excision wounds were made on the back of rats. Rats were divided into three groups, as control, vehicle, and treatment. Vehicle and treatment groups received polyethylene glycol and silymarin dissolved in polyethylene glycol, respectively. The control group did not receive any treatment. The wound tissues were removed on 5th, 10th and 15th day for histopathological analysis and total collagen determination by hydroxyproline assay. Results showed that silymarin increased epithelialization and decreased inflammation but did not have any effect on percentage of wound contraction, collagenization and hydroxyproline levels. It was concluded that silymarin can significantly stimulate epithelialization and reduce inflammation in full-thickness wounds in rats.

Immunoregulatory effects of glutathione during mesenchymal stem cell differentiation to hepatocyte-like cells

The role of mesenchymal stem cell in cellular therapy is the subject of interest for many researchers. The differentiation potential of MSCs and abilities in modulations of the recipient's immune system makes them important cells in tissue regenerative studies. MSCs by releasing the proinflammatory cytokines play important role in immunomodulatory systems; however the signaling pathways for releasing of these mediators are not well understood. Glutathione has been shown to play a role in modulation of cytokines in hepatogenic differentiation. In the current study we aimed to investigate the effects of buthionine sulfoximine [BSO, inhibitor for glutathione synthesis] and N-acetylecystin [NAC, an inhibitor for ROS generation] on proinflammatory cytokines production in a hepatogenic differentiation model. BSO and NAC significantly decreased IL-6 and TNF-alpha levels at 14 days of differentiation, whereas, NAC decreased the levels of IL-8 at days 2 and 14 of differentiation. Moreover, intracellular glutathione level during the differentiation was depleted. Our current study suggests a novel role of GSH as an immunopharmacological regulatory molecule during hepatogenic differentiation. Finally, this information may shed some light on the understanding of MSCs responses in transplantation and cell therapy in diseases such as chronic hepatic diseases.

Evaluation of potency of measles vaccine used in Iran: comparison of WHO and NIBSC method in cell culture

Measles has been a major cause of illness and death in children and vaccination against the disease is part of the WHO global immunization program. A suitable vaccine should create maximum immune response against the pathogen and must be safe for the user. Thus, after production, vaccines must be analyzed and controlled by the producer and confirm by relevant governmental organizations. The Food and Drug Control Lab [FDCL], Ministry of Health, is the secondary control center on potency of vaccines in Iran. In this study, we have set up the WHO and NIBSC methods in FDCL and compare these methods on determining the potency of measles vaccine. Measles vaccines were obtained from Razi Institute Iran. Nine dilutions of vaccine [10[-1] to 10[-5]] in 0.5 log interval were mixed with Vero cell suspension and seeded. In WHO method, the cells were incubated at 36°C for 10 days, during which the cells were checked for cytopatic changes everyday. To set up the assay, we tested the vaccine dilution with four different cell suspensions [2x10[5]-5x10[4]/well] and four different concentration of serum [2.5-10%]. Based on our results, in the assays, 5% serum and 1x10[5] cells were used. The potency assay was performed with six different vaccines produced in one batch and the mean potency for Measles was 10[4.32 +/- 0.24] CCID[50]/vial for a ten-dose vial. In NIBSC method following seeding of Vero cells, the medium was removed after 3 hours and overlay was added. Then the plates were incubated at 35°C for 10 days. After incubation period, the overlay was removed, the plaques were stained with methyl violet and counted. This assay was repeated three times and the mean of the results was 5.83 +/- 0.03 log[10] PFU/dose. In this study, we have set up the WHO and NIBSC methods and results indicated that the potency of the vaccine is in acceptable range in either method. Furthermore, the WHO method is simple and less time consuming compared to NIBSC which is complicated and requires more effort to produce reproducible results