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Background: Two field experiments were conducted at the Research and Production Station, National Research Centre, El-Nubaria Province, El-Behira Governorate, Egypt, during the two successive winter seasons of 2014/2015 and 2015/2016. This work aimed to study the enhancement effect of foliar application of nicotinamide at 5, 10, and 20 mg/L and/or humic acid at 5% on quality and quantity of faba bean plants (cultivar Sakha 4) grown under sandy soil conditions. Results: Data show that nicotinamide at 5, 10, and 20 mg/L and/or humic acid at 5% had a positive effect on growth parameters, photosynthetic pigments, seed yield, and yield components as well as some biochemical constituents of the yielded faba bean seeds (total carbohydrate, total phenolic content, proline, and free amino acids). Individually, nicotinamide treatments had a more positive effect than humic acid treatment and their effect was increased by increasing nicotinamide concentrations. The most promising treatment appeared due to the interaction between nicotinamide at 10 mg/L and humic acid. Hence, this treatment increased plant dry weight/plant by 32.67%, total photosynthetic pigments by 113.2%, seed yield/feddan by 110.16%, total carbohydrate by 9.4%, total phenolic content by 0.33%, proline by 24.83%, and free amino acids by 21.33%. Conclusions: We can conclude that nicotinamide and/or humic acid had a positive effect on growth parameters, photosynthetic pigments, seed yield, and yield components as well as some biochemical constituents of the yielded faba bean seeds. The most promising treatment appeared due to the interaction between nicotinamide at 10 mg/L and humic acid.

BackgroundNeurotensin has been found to promote colon carcinogenesis in rats and mice, and proliferation of human colon carcinoma cell lines, but the mechanisms involved are not clear. We have examined signalling pathways activated by neurotensin in colorectal and pancreatic carcinoma cells.MethodsColon carcinoma cell lines HCT116 and HT29 and pancreatic adenocarcinoma cell line Panc-1 were cultured and stimulated with neurotensin or epidermal growth factor (EGF). DNA synthesis was determined by incorporation of radiolabelled thymidine into DNA. Levels and phosphorylation of proteins in signalling pathways were assessed by Western blotting.ResultsNeurotensin stimulated the phosphorylation of both extracellular signal-regulated kinase (ERK) and Akt in all three cell lines, but apparently did so through different pathways. In Panc-1 cells, neurotensin-induced phosphorylation of ERK, but not Akt, was dependent on protein kinase C (PKC), whereas an inhibitor of the β-isoform of phosphoinositide 3-kinase (PI3K), TGX221, abolished neurotensin-induced Akt phosphorylation in these cells, and there was no evidence of EGF receptor (EGFR) transactivation. In HT29 cells, in contrast, the EGFR tyrosine kinase inhibitor gefitinib blocked neurotensin-stimulated phosphorylation of both ERK and Akt, indicating transactivation of EGFR, independently of PKC. In HCT116 cells, neurotensin induced both a PKC-dependent phosphorylation of ERK and a metalloproteinase-mediated transactivation of EGFR that was associated with a gefitinib-sensitive phosphorylation of the downstream adaptor protein Shc. The activation of Akt was also inhibited by gefitinib, but only partly, suggesting a mechanism in addition to EGFR transactivation. Inhibition of PKC blocked neurotensin-induced DNA synthesis in HCT116 cells.ConclusionsWhile acting predominantly through PKC in Panc-1 cells and via EGFR transactivation in HT29 cells, neurotensin used both these pathways in HCT116 cells. In these cells, neurotensin-induced activation of ERK and stimulation of DNA synthesis was PKC-dependent, whereas activation of the PI3K/Akt pathway was mediated by stimulation of metalloproteinases and subsequent transactivation of the EGFR. Thus, the data show that the signalling mechanisms mediating the effects of neurotensin involve multiple pathways and are cell-dependent.

Background: Shortage of water is a major problem facing Egypt; thus, it becomes necessary to use non-traditional sources of water such as saline water in irrigation. Overcoming the adverse effects of saline water and enhancing plant tolerance to salinity stress is the main challenge for increasing plant growth and productivity. Using a natural compound such as cysteine amino acid has an important effect in alleviating the adverse effect of salinity stress on different plant crops. Materials and methods: Two pot experiments were carried out during two successive summer seasons to study the beneficial role of cysteine (0, 20, and 40 mg/l) in enhancing growth, some metabolic process, and seed yield quality and quantity of soybean plant grown under salinity stress (0, 3000, and 6000 mg/l). Results: Salinity stress (3000 and 6000 mg/l) caused decreases in soybean growth criteria (plant height, number of branches and leaves/plant, dry weight of leaves and stem/plant), photosynthetic pigments and some element contents (nitrogen (N), phosphorus (P), and potassium (K)), and seed yield and yield components (number of pods/ plant, weight of pods/plant and number of seeds/plant) as well as oil%. Meanwhile, proline, H 2 O 2 and MDA contents, and superoxide dismutase activity were gradually increased by increasing salinity level. On the other hand, cysteine treatments improved growth and yield of soybean plant either irrigated with tap water or saline water. Cysteine treatments could alleviate the adverse effect of salinity stress on growth and yield of soybean plant through increasing photosynthetic pigments; proline content; N, P, and K contents; superoxide dismutase and catalase activities; and oil% accompanied by decreases in H 2 O 2 and MDA contents as compared with their corresponding controls. In addition, cysteine treatments and/or salinity stress exhibited differences in protein pattern from 112 to 19 kD molecular weight. The appearance of new protein bands reflected the expression of cysteine treatments and salinity stress. Conclusion: Cysteine treatments had a beneficial role in alleviating the adverse effect of salinity stress on soybean plant. Forty milligrams per liter of cysteine was the most effective treatment in enhancing salinity tolerance of soybean plant.

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Parthenolide (PT) is a sesquiterpene lactone isolated from Tanacetum parthenium . In this study, PT showed varying cytotoxic effects against different solid tumor cell lines. HCT116 (p53 +/+ ) colon carcinoma cells and their parental HCT116 knockout p53 (p53 -/- ) cell lines showed a resistance degree of 2.36. On the other hand, wild-type U87.MG cells or cells transfected with a deletion-activated EGFR cDNA (U87.MGΔEGFR) exhibited slight sensitivity toward PT. Multidrug-resistant MDA-MB-231-BCRP cells were even more sensitive toward PT than sensitive MDA-MB-231-pcDNA cells with a resistance degree of 0.07 (collateral sensitivity). To the best of our knowledge, hypersensitivity (collateral sensitivity) in MDA-MB-231-BCRP cell line is reported in this study for the first time. We attempted to identify the mechanism of collateral sensitivity. Firstly, we found that PT bound to IKK preventing IκBα degradation and eventually inhibition of the nuclear factor kappa B (NF-κB) pathway. Down-regulation of hypoxia inducing factor 1-alpha (HIF-1α) in MDA-MB-231-BCRP resistant cells may be a second mechanism, since it is a target gene of NF-κB. Moreover, PT also showed epigenetic effect by inhibition of HDAC activity as shown using both molecular docking and HDAC activity assay. Based on COMPARE and hierarchical cluster analyses, we found gene expression profiles that predicted sensitivity or resistance of 47 tumor cell lines toward PT. Interestingly, pathway analyses of gene expression profiles revealed NF-κB and HIF signaling as top networks of these genes, cellular functions and canonical pathways influencing the activity of PT against tumor cells. In conclusion, PT exerted profound cytotoxic activity against various cancer cell lines mainly against BCRP-overexpressing tumor cells, suggesting PT as novel candidate for cancer treatment.

Background: For scavenging reactive oxygen species, plant possess effective system that protect them from destructive oxidative reaction. Parts of this system as osmoprotectants and antioxidative enzymes are key elements in the defense mechanisms. A field experiment was conducted to evaluate the potential of foliar treatment of trehalose (Tre) with different concentrations (0, 0.1 mM, or 0.5 mM) in improving antioxidant defense system of quinoa plant under normal irrigation and drought stress conditions. Results: Drought stress caused significant increases in some osmoprotectants as glucose, trehalose, TSS, free amino acids, and proline. Meanwhile, trehalose foliar treatment with different concentrations significantly decreases in free amino acids and proline contents. More accumulation of the tested organic solutes of leaves (glucose, sucrose, trehalose, TSS) of the trehalose-treated plant in both normal irrigated and drought-stressed quinoa plants as compared with the corresponding controls. Treating quinoa plants with trehalose resulted in significant decrease in lipid peroxidation, hydrogen peroxide contents, and LOX activity in normal irrigated and drought-stressed plants. These decreases correlated with significant increases in total phenolic contents as compared with untreated control. Different concentrations of trehalose resulted in significant increases in antioxidant enzymes. Maximum increase antioxidant enzymes were observed by treating plants Tre at 0.5 mM either under normal irrigation or drought conditions. Conclusion: It could be concluded that foliar spray of trehalose was effective in improving quinoa performance by reducing hydrogen peroxide free radical and by enhancing antioxidant compounds (phenolics), compatible osmolytes, membrane stability, and antioxidant enzymes.