seyed naser ostad

This study was planned to explore the capability of nanoemulsions (NEs) consisting of CapryolTM 90 and oleic acid for the delivery of rapamycin (RAP). Permeability and cytotoxicity of RAP-loaded NEs were also inspected. Pseudo-ternary phase diagrams were created with oleic acid and CapryolTM 90 (as oil phase) and four surfactants and co-surfactants at various weight ratios (Rsm). Selected NEs from O/W region on the phase diagrams with the drug concentration of 1 mg/mL, were prepared via the spontaneous emulsification technique, characterized for particle size and subjected to stability tests at various temperatures over 9-12 months. Cumulative drug release was determined for a period of 48 h using a dialysis sac. The assay of RAP was determined using HPLC technique. Cytotoxicity of NEs was evaluated by MTT assay on breast cancer cell line, namely SKBR-3. The permeability of RAP-loaded NEs across Caco-2 monolayers was assessed by measurement of TEER (transepithelial electrical resistance) value. The intracellular uptake of coumarin 6-loaded NEs by SKBR-3 cells was also investigated using florescence microscopy. NEs containing oleic acid/Tween 20/propylene glycol, CapryolTM 90/Tween 20/iso-propanol, and CapryolTM 90/CremophorÒ RH40/TranscutolÒP showed more cytotoxicity and permeability compared with the RAP methanolic solution. The minimum toxic concentration of RAP in NE formulations was found to be 7.5 µg/mL. The highest intracellular uptake was observed for the NE composed of CapryolTM 90/Tween 20/iso-propanol which was in consistent with the results obtained from cytotoxicity and permeability tests. The overall results implicated that this novel carrier was effective for enhancing RAP permeation in Caco-2 cell membrane along with enhancement of cytotoxicity.

The Runt related transcription factors (RUNX) are recognized as key players in suppressing or promoting tumor growth. RUNX3, a member of this family, is known as a tumor suppressor in many types of cancers, although such a paradigm was challenged by some researchers. The TGF-β pathway governs major upstream signals to activate RUNX3. RUNX3 protein consists of several regions and domains. The Runt domain is a conserved DNA binding domain and is considered as the main part of RUNX proteins since. Herein, we compared the effects of Runt domains and full-Runx3 in cell viability by designing two constructs of Runx3, including N-terminal region and Runt domain. We investigated the effect of full-Runx3, N-t, and RD on growth inhibition in AGS, MCF-7, A549, and HEK293 cell lines which are different in TGF-β sensitivity, in the absence and presence of TGF-β. The full length RUNX3 did not notably inhibit growth of these cell lines while, the N-t and RD truncates showed different trends in these cell lines. Cell proliferation in the TGF-β impaired context cell lines (AGS and MCF-7) significantly decrease while in the A549 significantly increase. On the other hand, transfection of N-t and RD did not considerably affect the cell proliferation in the HEK293.Our results show that full-lenght RUNX3 did not affect the cell viability. Conversely, the N-t and RD constructs significantly changed cell proliferation. Therefore, therapeutic potentials for these truncated proteins are suggested in tumors with RUNX proteins dysfunction, even in the TGF-β impair context.

The aerial parts of Stachys laxa Boiss. and Buhse. from Siah-bishe in Mazandaran province, Stachys trinervis Aitch. and Hemsl. from Karaj in Alborz province, Stachys subaphylla Rech. F. and Stachys turcomanica Trautv. from Golestan province have been collected in May 2008. Total extracts were obtained through MeOH/H2O (80/20) and then partitioned between CHCl3, EtOAc and MeOH. These fractions and total extracts have been investigated for in-vitro cytotoxic activity against the colon carcinoma (HT-29), colorectal adenocarcinoma (Caco-2), breast ductal carcinoma (T47D) and Swiss mouse embryo fibroblast (NIH 3T3) cell lines using MTT assay (3-(4,5-di methyl thiazol-2-yl)-2,5-di phenyltetrazolium bromide). At each cell line, doses of 3.125, 6.25, 12.5, 25, 100, 200, 400 and 800 µg/mL in 1% (v/v) DMSO of all samples were tested. Ethyl acetate and chloroform fractions of Stachys laxa against proliferation of T47D and HT-29 cell lines and chloroform fraction of Stachys subaphylla and Stachys subaphylla ethyl acetate fraction toward T47D cell line exhibited highest cytotoxic activity (IC50 < 50 µg/mL). Ethyl acetate and chloroform fractions of Stachys turcomanica against HT-29 cell line, except methanol fraction of Stachys subaphylla, the other extrcts on T47D cell line, represented moderate cytotoxic activity (IC50 < 70 µg/mL). All fractions of S. trinervis demonstrated no effective cytotoxic activity. IC50 values confirmed that the growth and proliferation of HT-29 and T47D cells were most affected by chloroform and ethyl acetate fractions of Stachys laxa and Stachys turcomanica due to their nonpolar compounds.

Studies on biomedical applications of nanoparticles are growing with a rapid pace. In medicine, nanoparticles may be the solution for multi-drug-resistance which is still a major drawback in chemotherapy of cancer. In the present study, we investigated the potential cytotoxic effect of silver nanoparticles (Ag NPs) and silver ions (Ag+) in both parent and tamoxifen-resistant T47D cells in presence and absence of tamoxifen. Ag NPs were synthesized (< 28 nm) and MTT assay was carried out. The associated IC50 values were found to be: 6.31 g/ml for Ag NPs/parent cells, 37.06 g/ml for Ag NPs/tamoxifen-resistant cells, 33.06 g/ml for Ag+/parent cells and 10.10 g/ml for Ag+/resistant cells. As a separate experiment, the effect of subinhibitory concentrations of Ag NPs and Ag+ on the proliferation of tamoxifen resistant cells was evaluated at non-toxic concentrations of tamoxifen. Our results suggested that in non-cytotoxic concentrations of silver nanomaterials and tamoxifen, the combinations of Ag+-tamoxifen and Ag NPs-tamoxifen are still cytotoxic. This finding may be of great potential benefit in chemotherapy of breast cancer; since much lower doses of tamoxifen may be needed to produce the same cytotoxic effect and side effects will be reduced.

Many researches have been conducted on islet cell's transplantation for a definitive treatment of diabetes mellitus type1. As the viability of the islets is the most important factor in predicting the transplantation prognosis, we have designed a study to isolate rat's islets. The aim of the study was to assess the viability of the islets at different stages and suggest the best transplantation time. Pancreatic islets were isolated from male rats (250-300gr) by standard surgical procurement followed by intraductal HBSS distension, chopping and digestion with collagenase (type V). After being centrifuged for 3 times, the islets were then hand-picked and incubated in 37oC with RPMI 1640 media for 6 days. Each well contained 35-45 islets. Viability of islets was assessed by 2 independent investigators, giving score 0-2 to the color of islets under florescent microscope after Propidium iodide/Acridine orange staining at 6 times: just after the incubation, 24h, 48h, 3rd day, 5th and 6th day. The viability of the islet cells was gradually increased after the incubation as we had the most viability rate after the second day, while it decreased after this period and reached the least rate on the 5th and 6th day. The islet's viability increased following the cell culture after the isolation procedure, as they have the best condition for transplantation after 48 hours. As the islets’ viability is the most critical point in transplantation, further studies evaluating the effects of different interventions on viability is needed.

Many researches have been conducted on islet cell's transplantation for a definitive treatment of diabetes mellitus type1. As the viability of the islets is the most important factor in predicting the transplantation prognosis, we have designed a study to isolate rat's islets. The aim of the study was to assess the viability of the islets at different stages and suggest the best transplantation time.
Pancreatic islets were isolated from male rats (250-300gr) by standard surgical procurement followed by intraductal HBSS distension, chopping and digestion with collagenase (type V). After being centrifuged for 3 times, the islets were then hand-picked and incubated in 37oC with RPMI 1640 media for 6 days. Each well contained 35-45 islets. Viability of islets was assessed by 2 independent investigators, giving score 0-2 to the color of islets under florescent microscope after Propidium iodide/Acridine orange staining at 6 times: just after the incubation, 24h, 48h, 3rd day, 5th and 6th day.
The viability of the islet cells was gradually increased after the incubation as we had the most viability rate after the second day, while it decreased after this period and reached the least rate on the 5th and 6th day.
The islet's viability increased following the cell culture after the isolation procedure, as they have the best condition for transplantation after 48 hours. As the islet's viability is the most critical point in transplantation, further studies evaluating the effects of different interventions on viability is needed.

Three major flavonoid fractions were separated from a methanol extract of Calendula officinalis flowers by preparative TLC. These fractions were evaluated for the inhibition of parent and tamoxifen resistant T47D human breast cancer cells. We also examined the effect of quercetin and isorhamnetin on the growth of parent and resistant T47D cells in the presence and absence of tamoxifen. It was found that quercetin increased cell proliferation of the resistant T47D cells at the presence of tamoxifen but no effect was detected by using quercitin alone. The fractions isolated from  Calendula officinalis did not show any inhibitory effects on the cells. Isorhamnetin did not have any proliferative or anti-proliferative activity on the both cell lines.