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Tamoxifen is routinely used for treatment of Estrogen-positive breast carcinoma. Approximately, 50% of patients with metastatic cancer will develop resistance to Tamoxifen. In this research, Tamoxifen was combined with the anti-cancer compound Curcumin. Diblocknanopolymer was used to package the new formulation of Curcumin and Tamoxifen. Anti-cancer efficacy of the obtained compound was evaluated in Tamoxifen-sensitive (TS). MCF-7, Tamoxifen-resistant (TR) MCF-7 cancer cells and Fibroblast cells. MTT assay was used to evaluate anti-proliferation and toxicity. Flow cytometry and Annexin-V-FLUOS were used to assay anti-proliferation and induction of apoptosis respectively. Our results indicate that the obtained nano-compound is less toxic to normal cells compared to Tamoxifen alone, and has higher anti-proliferation and pro-apoptotic activity on TS-MCF-7 and TR-MCF-7. The nanopolymer reduces the Tamoxifen toxicity in normal cells and counters the developed resistance to the drug in cancer cells. [ABSTRACT FROM AUTHOR]

Creatine was reported to induce bone marrow stromal cells (BMSC) into GABAergic neuron-like cells (GNLC). In a previous study, creatine was used as a single inducer for BMSC into GNLC with low yield. In this study, BMSC-derived neurospheres (NS) have been used in generating GABAergic phenotype. The BMSC were isolated from adult rats and used in generating neurospheres and used for producing neural stem cells (NSC). A combination of all-trans-retinoic acid (RA), the ciliary neurotrophic factor (CNTF), and creatine was used in order to improve the yield of GNLC. We also used other protocols for the transdifferentiation including RA alone; RA and creatine; RA and CNTF; and RA, CNTF, and creatine. The BMSC, NSC, and GNLC were characterized by specific markers. The activity of the GNLC was evaluated using FM1-43. The isolated BMSC expressed Oct4, fibronectin, and CD44. The NS were immunoreactive to nestin and SOX2, the NSC were immunoreactive to nestin, NF68 and NF160, while the GNLC were immunoreactive to GAD1/2, VGAT, GABA, and synaptophysin. Oct4 and c-MYC, pluripotency genes, were expressed in the BMSC, while SOX2 and c-MYC were expressed in the NSC. The activity of GNLC indicates that the synaptic vesicles were released upon stimulation. The conclusion is that the combination of RA, CNTF, and creatine induced differentiation of neurosphere-derived NSC into GNLC within 1 week. This protocol gives higher yield than the other protocols used in this study. The mechanism of induction was clearly associated with several differential pluripotent genes. [ABSTRACT FROM AUTHOR]

Objective(s): Despite the good results of anticancer activities by curcumin, there are some hurdles that limit the use of curcumin as an anticancer agent. Many methods were examined to overcome this defect like the use of the dendrosomal curcumin (DNC). There is increasing evidence that miRNAs play important roles in biological processes. In this study, we focus on the roles of microRNA-21 in the anti-cancer effects of DNC in breast cancer. Materials and Methods: Also, we have used different methods such as MTT, apoptosis, cell cycle analysis, transwell migration assay and RT-PCR to find out more. Results: We observed that miR-21 decreased apoptotic cells in both cells (from 6.35 % to 0.34 % and from 7.72 % to 1.32 % orderly) and DNC increased it. As well as, our findings indicated that cell migration capacity was increased by miR-21 over expression and was decreased by DNC. The combination of miR-21 vector transfection and DNC treatment showed lower percentage of apoptotic cells or a higher level of penetration through the membrane compared with DNC treatment alone. Furthermore, DNC induced a marked increase in the number of cells in sub G1/G1 phase and a decrease in G2/M phase of the cell cycle in both; but, we observed reverse results compared it, after transfection with miR-21 vector. Conclusion: We observed that miR-21 suppress many aspects of anti-cancer effects of DNC in breast cancer cells, it seems that co-treatment with DNC and mir-21 down-regulation may provide a clinically useful tool for drug-resistance breast cancer cells. [ABSTRACT FROM AUTHOR]

Tyrosinase (Ec: 1.14.18.1) is a copper - containing enzyme which is distributed in all domains of life such as prokaryote, eukaryote, mammals, invertebrates and plants. Tyrosinase catalyzes the oxidation of monophenols to diphenols and diphenols to o-quinones . The tyrosinase crystallographic data shows two histidine -rich regions named CuA and CuB. A loop containing residues M374, S375 and V377 connects the CuA and CuB Centers. This loop is essential for stability of the enzyme. In this study, site directed mutagenesis was used for the replacement of M374 by Arginine and Lysine.in synthesized cDNA cloned in pET 28b (+) . These mutations don't affect the orientation of the Histidin 367(H367) side chain, resulting in loss of activity. [ABSTRACT FROM AUTHOR]

Purpose:We examined the potential of a dendrosomal nanoformulation of curcumin (DNC) for intervention of ionizing radiation (IR)-induced damage (particularly leading to atherosclerosis), employing an irradiated THP-1 macrophage model. Materials and methods:Differentiated THP-1 macrophages were irradiated and treated with curcumin or DNC nanoformulation (and oxidized low density lipoprotein, ox-LDL, to promote foam cells). Chemical, biochemical, and genetics tools including viability and apoptosis, multiple ELISA, real-time PCR, Western blotting, enzyme activity, and fluorimetry assays were employed to illustrate IR damage as well as the DNC intervention potential. Results:DNCper seat 10 μM exerted no cytotoxic effects on macrophages. However, it caused apoptosis in 2 Gy-irradiated macrophages which were treated with ox-LDL, chiefly through a caspase-dependent pathway involving caspase-3. Concurrently, 10 μM DNC prevented the IR-induced rise in lipid accumulation (72% decrease compared to IR control,p< .0001), dil-oxLDL uptake (78% decrease,p< .005), protein and mRNA expression of cholesterol influx genes, CD36 and SR-A, NF-κB activation (81% less binding activity,p< .001; and lower nuclear presence of p65), cytokine (monocyte chemoattractant protein-1 and interleukin-1β) release, reactive oxygen species (ROS), and oxidative damage to DNA (37% decrease in 8-OHdG,p< .05) and lipids (62% decrease in 8-isoprostane,p< .005). DNC facilitated the uptake of curcumin in irradiated macrophages, increased glutathione peroxidase expression and activity, restored glutathione (GSH) level, and upregulated the expression of a cholesterol efflux gene, ABCA1. Two other antioxidants, resveratrol and N-acetyl cycteine (NAC), could simulate some of the beneficial effects of DNC against IR-induced CD36 expression and lipid accumulation, which were obviated by buthionine sulfoximine (BSO) pre-treatment of macrophages. However, some modulatory effects of DNC, particularly on lipid accumulation and the expression of SR-A and ABCA1 genes, seemed to be independent of its antioxidant effect, since they were still observed in BSO-pretreated macrophages, depleted of GSH. Conclusions:DNC treatment suppresses IR-induced oxidative damage, inflammation, and foam cell formation in macrophages through multiple mechanisms. [ABSTRACT FROM PUBLISHER]

The melanoma differentiation-associated gene-7 (MDA-7) gene, also termed interleukin-24 (IL-24), is a tumor suppressor gene that induces apoptosis in a broad scope of malignant neoplastic cells. The apoptosis induction capacity of the MDA-7/IL-24 gene is partially associated with adhering to cognate receptors. The current study aimed to enhance the antitumor effect of IL-24. The intrinsic signal sequence of IL-24 replaced with a fused artificial signal (secrecon)-RGD4C sequence and its impact was evaluated in HepG2 cells. The modified SP.RGD.IL-24 and native IL-24 cDNA sequences were cloned into the pcDNA3.1 expression vector. Subsequently, the expression level, secretion efficacy and targeting propensity of the modified SP.RGD.IL-24 product compared with normal IL-24 by were determined by enzyme-linked immunosorbent assay. The constructs were then transfected into HepG2 and LX-2 cells as tumor and normal hepatic cell lines, respectively. The expression level of the pro-apoptotic DNA damage inducible transcript 3 (Gadd153) and BCL2 associated X apoptosis regulator (Bax) genes in the different groups were compared by reverse transcription-quantitative polymerase chain reaction. Additionally, the rate of apoptosis induction of modified and intact IL-24 sequences was compared by flow cytometry analysis of cells following their propidium iodide/annexin V staining. SP.RGD-IL-24 protein was expressed and secreted in a similar manner to native IL-24, however, the modified SP.RGD.IL-24 adhered to tumor cells more efficiently than IL-24 (P<0.05). SP.RGD.IL-24 significantly induced upregulation of Gadd153 and Bax in HepG2 cells compared with native IL-24 (P<0.05). However, neither had a significant impact on the expression level of pro-apoptotic genes in LX-2 cells. Flow cytometry analysis also indicated that modified SP.RGD.IL-24 induced apoptosis more than native IL-24 in HepG2 cells (P<0.05). In conclusion, the novel generated RGD-coupled IL-24 construct exhibited sufficient anticancer activity compared with the native IL-24. The results of the current study provide novel insights for the future of cytokine targeting and indicates its potential capacity as a valuable candidate for gene therapy methods. [ABSTRACT FROM AUTHOR]

N-Acyl-homoserine lactones (AHLs)-dependent quorum sensing (QS) system(s) is recruited by the soft rot bacterium Dickeya chrysanthemi for coordinating its social activities such as secretion of plant cell wall-degrading enzymes, while the main signal molecule and quantity dependence of virulence to QS in this bacterium have not been clarified. To do this end, the involvement of AHLs in African violet leaves and potato tuber maceration; swarming motility; pectate lyase and polygalacturonase enzymes production and in planta expression of virulence genes including pelE, pehX and pemA by electroporating two quorum-quenching vectors. The expression of two types of AHL-lactonase expressing vector caused dramatic decrease in swarming motility, production of pectinolytic enzymes and macerating of plant tissues. The maximum ability of quenching of QS in repression of D. chrysanthemi virulence was assessed quantitatively by q-RT-PCR, as expression of pelE, pehX and pemA genes were decreased 90.5-92.18 % in quenched cells. We also showed that virulence and pathogenicity of this bacterium was under the control of DHL-dependent QS system and that the existence of second DHL operating system is probable for this bacterium. Thus, this signal molecule would be the key point for future research to design DHL-specific lactonase enzymes using bioinformatics methods. [ABSTRACT FROM AUTHOR]

Objectives: To investigated the potential of a novel dendrosomal nanoformulation of curcumin (DNC) in blocking radiation-induced changes in irradiated human umbilical vein endothelial cells (HUVECs), and their adhesion to human THP-1 monocytoid cells. Results: Co gamma rays reduced viability, raised the expression of adhesion molecules, ICAM-1, VCAM-1 and E-selectin (mRNA and protein), augmented the adhesion of THP-1 cells to HUVECs, activated NF-κB binding, increased the release of pro-inflammatory cytokines (IL-6, IL-8 and MCP-1) and induced oxidative damage (reduced glutathione declined, while 8-OHdG and TBARS increased). 5 µM DNC significantly inhibited these radiation-induced changes, activated the Nrf-2 pathway, and effectively suppressed THP-1 adhesion to HUVECs, implicating p38 MAPK signaling. Conclusion: DNC treatment is a potential preventive method against inflammation and vascular damage from ionizing radiation. [ABSTRACT FROM AUTHOR]

Protection against ionizing radiation (IR) and sensitization of cancer cells to IR are apparently contrasting phenomena. However, curcumin takes on these contrasting roles leading to either protection or enhanced apoptosis in different irradiated cells. Here we studied whether pretreatment with free curcumin or a novel dendrosomal nanoformulation of curcumin (DNC) could exert protective/sensitizing effects on irradiated THP-1 leukemia cells. We employed assays including MTT viability, clonogenic survival, DNA fragmentation, PI/Annexin V flow cytometry, antioxidant system (ROS, TBARS for lipid peroxidation, 8-OHdG and γH2AX for DNA damage, glutathione, CAT and GPx activity, enzymes gene expression), ELISA (NF-κB and Nrf2 binding, TNF-α release), caspase assay, siRNA silencing of caspase-3, and western blotting to illustrate the observed protective role of curcumin in comparison with the opposite sensitizing role of its nanoformulation at a similar 10 μM concentration. The in vivo relevance of this concentration was determined via intraperitoneal administration in mice. Curcumin significantly enhanced the antioxidant defense, while DNC induced apoptosis and reduced viability as well as survival of irradiated THP-1 cells. Nrf2 binding showed an early rise and fall in DNC-treated cells, despite a gradual increase in curcumin-treated cells. We also demonstrated that DNC induced apoptosis in THP-1 cells via caspase-3 activation; whereas in combination with radiation, DNC alternatively employed a caspase-independent apoptosis pathway involving cytochrome c release from mitochondria. [ABSTRACT FROM AUTHOR]

Bioremediation of toxic metals by magnetotactic bacteria and magnetic separation of metal-loaded magnetotactic bacteria are of great interest. This bioprocess technique is rapid, efficient, economical, and environmentally friendly. In this study, cobalt removal potential of a novel isolated magnetotactic bacterium ( Alphaproteobacterium MTB-KTN90) as a new biosorbent was investigated. The effects of various environmental parameters in the cobalt removal and the technique of magnetic separation of cobalt-loaded bacterial cells were studied. Cobalt removal by MTB-KTN90 was very sensitive to pH solution; higher biosorption capacity was observed around pH 6.5-7.0. When biomass concentration increased from 0.009 to 0.09 g/l, the biosorption efficiency increased from 13.87 % to 19.22 %. The sorption of cobalt by MTB-KTN90 was rapid during the first 15 min (859.17 mg/g dry weight). With the increasing of cobalt concentrations from 1 to 225 mg/l, the specific cobalt uptake increased. Maximum cobalt removal (1160.51 ± 15.42 mg/g dry weight) took place at optimum conditions; pH 7.0 with initial cobalt concentration of 115 mg/l at 60 min by 0.015 g/l of dry biomass. The results showed maximum values for constants of Langmuir and Freundlich models so far. The biosorption mechanisms were studied with FTIR, PIXE, and FESEM analysis. Cobalt-loaded MTB-KTN90 had ability to separate from solution by a simple magnetic separator. Magnetic response in MTB-KTN90 is due to the presence of unique intracellular magnetic nanoparticles (magnetosomes). The orientation magnetic separation results indicated that 88.55 % of cobalt was removed from solution. Consequently, Alphaproteobacterium MTB-KTN90 as a new biosorbent opens up good opportunities for the magnetic removal of cobalt from the polluted aquatic environments. [ABSTRACT FROM AUTHOR]

Objective(s): Glioblastoma is the most lethal tumor of the central nervous system. Here, we aimed to evaluate the effects of exogenous delivery of p53 and a nanoformulation of curcumin called dendrosomal curcumin (DNC), alone and in combination, on glioblastoma tumor cells. Materials and Methods: MTT assay was exploited to measure the viability of U87-MG cells against DNC treatment. Cells were separately subjected to DNC treatment and transfected with p53-containing vector and then were co-exposed to DNC and p53 overexpression. Annexin-V-FLUOS staining followed by flow cytometry and real-time PCR were applied to examine apoptosis and analyze the expression levels of the genes involved in cell cycle and oncogenesis, respectively. Results: The results of cell viability assay through MTT indicated that DNC inhibits the proliferation of U87-MG cells in a time- and dose-dependent manner. Apoptosis evaluation revealed that p53 overexpression accompanied by DNC treatment can act in a synergistic manner to significantly enhance the number of apoptotic cells (90%) compared with their application alone (15% and 38% for p53 overexpression and DNC, respectively). Also, real-time PCR data showed that the concomitant exposure of cells to both DNC and p53 overexpression leads to an enhanced expression of GADD45 and a reduced expression of NF-κB and c-Myc. Conclusion: The findings of the current study suggest that our combination strategy, which merges two detached gene (p53) and drug (curcumin) delivery systems into an integrated platform, may represent huge potential as a novel and efficient modality for glioblastoma treatment. [ABSTRACT FROM AUTHOR]

Cancer recurrence is believed to be one of the major reasons for the failure of cancer treatment strategies. This biological phenomenon could arise from the incomplete eradication of tumour cells after chemo- and radiotherapy. Recent developments in the design of models reflecting cancer recurrence and in vivo imaging techniques have led researchers to gain a deeper and more detailed insight into the mechanisms underlying tumour relapse. Here, we provide an overview of three important drivers of recurrence including cancer stem cells (CSCs), neosis, and phoenix rising. The survival of cancer stem cells is well recognized as one of the primary causes of therapeutic resistance in malignant cells. CSCs have a relatively latent metabolism and show resistance to therapeutic agents through a variety of routes. Neosis has proven to be as an important mechanism behind tumour self-proliferation after treatment which gives rise to the expansion of tumour cells in the injured site via production of Raju cells. Phoenix rising is a pro-recurrence pathway through which apoptotic cancer cells send strong signals to the neighbouring diseased cells leading to their multiplication. The mechanisms involved in therapeutic resistance and tumour recurrence have not yet been fully understood and mostly remain unexplained. Without doubt, an improved understanding of the cellular machinery contributing to recurrence will pave the way for the development of novel, sophisticated and effective anti-tumour therapeutic strategies which can eradicate tumour without the threat of relapse. [ABSTRACT FROM AUTHOR]

The side-effects observed in conventional therapies have made them unpromising in curing Hepatocellular carcinoma; therefore, developing novel treatments can be an overwhelming significance. One of such novel agents is curcumin which can induce apoptosis in various cancerous cells, however, its poor solubility is restricted its application. To overcome this issue, this paper employed dendrosomal curcumin (DNC) was employed to in prevent hepatocarcinoma in both RNA and protein levels. Hepatocarcinoma cells, p53 wild-type HepG2 and p53 mutant Huh7, were treated with DNC and investigated for toxicity study using MTT assay. Cell cycle distribution and apoptosis were analyzed using Flow-cytometry and Annexin-V-FLUOS/PI staining. Real-time PCR and Western blot were employed to analyze p53, BAX, Bcl-2, p21 and Noxa in DNC-treated cells. DNC inhibited the growth in the form of time-dependent manner, while the carrier alone was not toxic to the cell. Flow-cytometry data showed the constant concentration of 20 μM DNC during the time significantly increases cell population in SubG1 phase. Annexin-V-PI test showed curcumin-induced apoptosis was enhanced in Huh7 as well as HepG2, compared to untreated cells. Followed by treatment, mRNA expression of p21, BAX, and Noxa increased, while the expression of Bcl-2 decreased, and unlike HepG2, Huh7 showed down-regulation of p53. In summary, DNC-treated hepatocellular carcinoma cells undergo apoptosis by changing the expression of genes involved in the apoptosis and proliferation processes. These findings suggest that DNC, as a plant-originated therapeutic agent, could be applied in cancer treatment. [ABSTRACT FROM AUTHOR]

Animal models simulate different aspects of human diseases and are essential to get a better understanding of the disease, studying treatments and producing new drugs. Experimental autoimmune encephalomyelitis (EAE) is a preferred model in multiple sclerosis research. Common EAE model in Lewis rats is induced using MBP peptide as a myelin antigen which results in a monophasic disease course. In the present study, EAE was induced in Lewis rats by homogenized guinea pig spinal cord along with or without pertussis toxin (PT). When PT was used, EAE turned into remitting–relapsing form and worsen the clinical symptoms. Higher inflammation and oxidative stress marker gene expression was observed when PT was administrated. [ABSTRACT FROM AUTHOR]

A pullulanase-encoding gene from psychrotrophic Exiguobacterium sp. SH3 was cloned and expressed in both E. coli and Bacillus subtilis. The functional recombinant enzyme (Pul-SH3) was purified as a His-tagged protein. Pul-SH3 was characterized to be a cold-adapted type I pullulanase with maximum activity at 45 °C. Using fluorescence spectroscopy, the melting temperature of Pul-SH3 was determined to be about 52 °C. The enzyme was able to hydrolyze pullulan, soluble starch, potato starch, and rice flour. It was exceptionally tolerant in the pH range of 4-11, exhibiting maximum activity at pH 8.5 and more than 60 % of the activity in the pH range of 5-11. Being a detergent-tolerant pullulanase, Pul-SH3 retained 99, 89, and 54 % of its activity at 10 % concentration of Triton-X100, Tween 20, and SDS, respectively. The enzyme also exhibited an activity of 80.4 and 93.7 % in the presence of two commercial detergents, Rika (7.5 % v/v) and Fadisheh (2.5 % w/v), respectively. The enzyme was even able to remain active by 54.5 and 85 % after 10-day holding with the commercial detergents. Thermal stability of the enzyme could w on silica. Pul-SH3 with several industrially important characteristics seems desirable for cold hydrolysis of starch. [ABSTRACT FROM AUTHOR]