فصلنامه تازه های بیوتکنولوژی سلولی مولکولی
پیاپی 10 (بهار 1392)

Introduction and Gastrointestinal cancers are among the most frequently occurring cancers worldwide. Environmental and inherited factors could be contributed to the etiology of these cancers. Lifestyle factors such as dietary habits، physical activity and smoking may play an important role in the occurrence of these types of cancer. Gastric cancer is the fourth most common cancer and second leading cause of cancer death worldwide. Nisin is an antimicrobial peptide with 34 amino acids and due to having the Lantionin amino acid categorized as Lantibiotic peptides family. The purpose of this study is to evaluate the nisin effect on cell cytotoxicity of gastric cancer. For evaluation of nisin cytotoxic effect on AGS cell line، they were cultured in 96-well plates at a density of 1×104 cells per well and incubated for overnight 37°C. After 24 h، cells were treated in a triplicate manner with different concentrations of nisin including 0، 10، 20، 40، 60 and 80 micromolar and for each concentration was repeated 3 times. The cytotoxic effect of nisin on cells in the intervals 24، 48 and 72 h after treatment were investigated. In each interval with concentration increase، cells viability reduction was observed، In addition، Cytotoxicity increased in longer time treatment. Many peptides having biological activities are used as therapeutic agents. These peptides، including nisin، which causes death in AGS cells، Cytotoxicity effect of nisin on cells is concentration and time depended.

Aime and The aim of this study was to evaluate let-7 family members expression in activated naïve CD4+ T cells and IL-2 induced cells. Let-7 family has oncogenic and tuomor suppressive activity in different cells. Naïve CD4+ T cells were activated by anti-CD2، CD3، CD28 microbeads. After 3 days، the activated cells stimulated by IL-2 (0. 75ng/ml). after 72h total RNA extracted the cells and c-DNA synthesis and Q-RT-PCR performed by miRCURY LNATM universal RT miRNA PCR kit. miRNA expression analyzed by geneX software and ∆∆Ct method. Five members of let-7 family over-expressed in activated cells compared with IL-2 induced cells. Targets Predicted by miRDB and miRanda software including families of DUSP، PTPN and SOCS that two first families inhibit TCR signaling and latest suppress JAK/STAT pathway. It appears that let-7 family play important role in clonal expansion of activated CD4+ T cells by specific genes suppression in post-transcriptional levels for appropriated immune response.

Aim and The quinoxaline and pyrazoline derivatives have variety of biological effects، which made them useful pharmaceutical agents، such as cytotoxicity activities، that will be appropriate in chemotherapy of tumors. In this study، 5''-phenyl-2''،4''-dihydrospiro [indeno[1،2-b] quinoxaline-11،3''-pyrazole] compound was synthesized and studied cytotoxic effect on K562 cell line and PBMC by MTT assay. 5''-Phenyl-2''،4''-dihydrospiro [indeno[1،2-b] quinoxaline-11،3''-pyrazole] compound by one pot assay was synthesized and studied anti tumor activity on blood cancer cell line، K562، and healthy human hole blood activated PBMC by MTT assay. In addition، cytotoxic effects of cisplatin on the same cells were studied. This compound showed antitumor activity with IC50 of 0. 92 and 0. 75 µg/ml respectively on K562 cell line and PBMC+PHA. While cisplatin، as a kind of standard drug in chemotherapy، inhibited proliferation of the same cells respectively with IC50، 1. 71 and 7. 8 µg/ml. The obtain results showed compound 4 is cytotoxic more than cisplatin on K562 cell line and activated PBMC by PHA.

Aim and The biological actions of the peptides are mediated upon binding with high affinity to specific receptors. Neurotensin is a tridecapeptide localized in central nervous system and in peripheral tissues. Three different receptor subtypes have been described for it among which the first one showing high affinity binding for NT was observed in ductal pancreatic adenocarcinoma. Since pancreas carcinoma is among the most frequent causes of cancer deaths، the need to use new radiopharmaceuticals which are able to diagnose cancer in the early steps is evident. A neurotensin analogue modified at the N-terminus by tetramine was obtained by solid phase peptide synthesis technique and s tandard fmoc strategy. Peptide conjugate was radiolabeled with 99mTc and s tability was tested in vitro in saline and human serum. Binding and internalization studies were carried out in neurotensin receptor expressing HT-29 cells. In vivo distribution studies were performed in normal mice. The radiolabeled complex prepared at high specific activities and >90% radiochemical yield. Peptide conjugate showed specific binding to neurotensin receptors. The radioligand showed high and specific internalization into HT-29 cells (22% at 4 h). In vivo distribution studies in mice have shown a low uptake of radioactivity in organs، such as the blood، bone، spleen، pancreas and muscle at 4 h post injection. A high uptake was found in the intestine، colon and kidneys. D ata show that this new labeled analogue exhibits favorable biodistribution pattern and is a specific radioligand for diagnostic of neurotensin receptor positive tumors.

Aim and Aloe vera is one of the important medicinal plants، that grow in warm-dried regions. In this study، fifty Aloe vera populations from five different areas from Iran، were evaluated for their morphological traits. During of growing season 18 morphological characters such as height، breadths of plant، number of leaves، length and width of leaf and were measured. Data was analyzed using SPSS software. The results showed that some characters had positive correlation. Leaf length with width of leaf had positive significant correlation at 5% level of significance. Borazjan population had the highest weight leaf (262 g)، diameter leaf (2. 5 cm). Bashagerd population had highest weight plant (18Kg) and flower length (120cm). Cluster analysis resulted in the populations being divided into three groups. Results indicated that، Iranian Aloe vera is completely different from the common aloe species with diversity that makes it a valuable genetic resource for breeding programs.

Aim and Cytochalasin B is presently being used as a cytokinesis inhibitor in the cell divisions to treat some types of cancer. Balb/c male mice (25-30 gr) are divided into 2 groups: control and experimental. The control group received distilled water whereas experimental groups were injected into abdominal cavity with cytochalasin B (1، 2، 3 and 5 mg/kg BW). After 24 hours، sacrificed after being anesthetized by chloroform. Both femora were dissected، and bone marrow cells were flushed out with 1 ml Kcl and pipetted several times. The cell suspension was centrifuged at 1000 rpm for 5 min، the supernatant was withdrawn، and the cell pellet was resuspended and placed on a clean glass slide. This research seeks to determine the appropriate dosage of cytochalasin B to inhibit cytoplasm divisions. 1، 2، 3، and 5 mg/kg. bw of the medicine was used per kilogram of mice weight and the result was evaluated 24 hours after the treatment. The micronuclei assay was used to detect binuclei pronormoblast. Statistical analysis was performed with ANOVA and Tukey using SPSS software. In this study، the results indicate the highest frequency of the binuclei pronormoblast (stopped in cytokinesis) when a 3mg/kg. bw dosage was taken for each kilogram of mice.

Vinca alkaloids, the dimeric Catharanthus roseus alkaloids, are a family of anti-mitotic drugs which used in cancer chemotherapy against a variety of hematological and solid tumors. These compounds interact with tubulin subunits and prevent microtubule assembly, inducing abnormal chromosome segregation in dividing cells and leading to aneuploidy. The aim of this study was to investigate Vincristine (VCR), the most important and naturally produced (from vacuoles) member of Vinca alkaloids family, genotoxicity effects on bone marrow cells in vivo in Balb/c mice. The research was performed by treating Balb/c mice with different doses of intraperitoneally administrated Vincristine. After 24 h, animals were killed to investigate genotoxicity and chromosomal abnormality induction in their bone marrow cells using micronucleus assay. Data were statistically analyzed by ANOVA using PASW18 software. Vincristine significantly induced micronucleus formation (p<0.05) at all doses in polychromatic erythrocytes. It induced genotoxicity in mice bone marrow and caused a detectable mitotic damage. Consequently, our finding showed that Vincristine has a high ability to induce micronucleus formation in normal mice bone marrow. The present research could be used in researches and investigations on mechanism of chromosomal abnormality formation and carcinogenesis.

Aim and Silver nano particles (NPs) or nanosilver (NS) are clusters of silver atoms that range in diameter from 1 to 100nm and are attracting interest as antibacterial and antimicrobial agents of applications in medicine. Resistance to antimicrobial agents by pathogenic bacteria has emerged in recent years and is a major reason for replacing of antibiotics with nano silver، but yet nanoparticle hazardous and toxic effects have not been studied extensively. One of the agent of semen extenders is antibiotics. We replaced antibiotics with nano silver and investigated mobility، progressive of sperm. also result of nano silver on the growth of semen''s bacteria was studied and them was compared with penicillin and streptomycin in similar conditions. Semen was diluted with citrate sodium، Yolk extender and was divided into nine portions. The control (sham) semen extender solution contained extended semen and no antibiotic and nanosilver، whereas streptomycin and penicillin solutions contained extended semen plus 1. 0 mg/mL of streptomycin and penicillin. Also semen was diluted with Citrate sodium، Yolk extender supplemented with different concentrations of silver nano particle. Here، the effects of different concentration of silver NPs on bull sperm at frequent times after1، 3 hours was evaluated. Mean percentages of motile and progressively motile sperm did not differ significantly among control (sham) and antibiotic and nanosilver -containing solutions after 1 hour. but after 3 hour، nanosilver was cytotoxic on bull sperm cells in more than 0. 1mL concentration. (p<0. 001) Control extended semen samples from ejaculates of bulls were contaminated with gram pasitive bacteria. Samples of antibiotic and concentration of 0. 005mL، 0. 01mL nanosilver had growth a few of bacteria. Nanosilver has good antibacterial properties in semen extender in more than 0. 05mL concentration. It can be suggested that antibiotics may be replaced with nano silver as antimicrobial agent in semen extenders in Some few concentration.

Aim and Regarding that the breast cancer is the most prevalent disease among women، Paclitaxel، an anti-cancer drug، could be used in treatment of this disease. As Paclitaxel has some adverse effects، we made use of the nanoliposomal drug delivery technology in order to reduce adverse effects and improve drug efficacy. Certain ratios of Phosphatidylinositol choline، cholesterol and Paclitaxel were synthesized to prepare nanoliposomal paclitaxel. The mean diameter of the nanoliposomal paclitaxel was measured by the Zeta sizer device. Using dialysis، the pattern of drug release from nanoliposomes has been studied and the cytotoxicity effect of the nanoliposomal drug was finally measured with the MTT assay. Using the Zeta sizer device، the mean diameter of the nanoliposomal Paclitaxel was obtained 421. 4 nanometers and its encapsulation efficiency was 91. 3%. By dialysis، drug release in the nanoliposomal Paclitaxel formulation was studied within 28 hours which was 5. 53%. The present study showed that the cytotoxicity effect of nanoliposomal Paclitaxel is more than that of the standard form.

Aim and Trametes gibbosa belongs to Polyporaceae family and Polyporales order having many medicinal effects in whole world. The aim of this study is investigation and comparison of antioxidant propertie with two methods DPPH & RP and determination of phenol and flavonoid content. Methanolic extract for examining of antioxidant properties was prepared. Two methods for determining of antioxidant properties were considered as DPPH and RP. BHT and BHA as synthetic antioxidants were considered and we prepared eight concentrations (1000-12. 5 µ g/ml) from methanolic extract of fungi، BHT & BHA. Phenol and flavonoid content of methanolic extract T. gibbosa were determined. antioxidant activities dependent on concentration. DPPH radical scavenging activity was the highest at the concentration of 750 μ g mL-1 (19. 61%) and was the lowest at the concentration of 12. 5 μ g mL-1 (4. 18%). Reducing power capacity was the highest at the concentration of 1000 μ g mL-1 (0. 328) and was the lowest at the concentration of 12. 5 μ g mL-1 (0. 129). The total phenol content of methanolic extract was 1. 30±0. 03 mg GAE g-1 FW and total flavonoid content of methanolic extract was 1. 03± 0. 05 mg QUE g-1 FW. the results showed that in higher concentrations، antioxidant activity was higher than lower concentrations. In both of methods for determining of antioxidant properties، the results showed that antioxidant activity was strongly dependent on concentration. totally، the result showed that the methanolic extract of the sample no have high antioxidant activity.

Aim and Per o xi d ases a re o n e o f t he m o st i m p o rta n t enz y mes that p artici pa t es in many p h y s i o lo g i c al p rocesses in p l a n ts. Peroxidases are heme containing proteins that utilize H2O2 in the oxidation of various organic and inorganic substrates. In this research، the activity of peroxidase، was investigated in Crocus sativus L. co r m s extracts. The activity of peroxidase was studied with different c on c e ntr at i o n o f H 2 O 2 and pH measurement.