Brassinolide alleviates salt stress and increases antioxidant activity of cowpea plants (Vigna sinensis)

Soil salinity is one of the most severe factors limiting growth and physiological response in Vigna sinensis plants. Plant salt stress tolerance requires the activation of complex metabolic activities including antioxidative pathways, especially reactive oxygen species and scavenging systems within the cells which can contribute to continued growth under water stress. The present investigation was carried out to study the role of brassinolide in enhancing tolerance of cowpea plants to salt stress (NaCl). Treatment with 0.05?ppm brassinolide as foliar spray mitigated salt stress by inducing enzyme activities responsible for antioxidation, e.g., superoxide dismutase, peroxidase, polyphenol oxidase, and detoxification as well as by elevating contents of ascorbic acid, tocopherol, and glutathione. On the other hand, total soluble proteins decreased with increasing NaCl concentrations in comparison with control plants. However, lipid peroxidation increased with increasing concentrations of NaCl. In addition to, the high concentrations of NaCl (100 and 150?mM) decreased total phenol of cowpea plants as being compared with control plants. SDS-PAGE of protein revealed that NaCl treatments alone or in combination with 0.05?ppm brassinolide were associated with the disappearance of some bands or appearance of unique ones in cowpea plants. Electrophoretic studies of ??-esterase, ??-esterase, polyphenol oxidase, peroxidase, acid phosphatase, and superoxide dismutase isoenzymes showed wide variations in their intensities and densities among all treatments.     

Role of miRNA-210, miRNA-21 and miRNA-126 as diagnostic biomarkers in colorectal carcinoma: impact of HIF-1α-VEGF signaling pathway

Colorectal cancer (CRC) is a major cause of death worldwide. Novel non-invasive, high diagnostic value screening test is urgently needed to improve survival rate, treatment and prognosis. Stable, small, circulating microRNA (miRNA) offers unique opportunities for the early diagnosis of several diseases. It acts as tumor oncogenes or suppressors and involve in cell death, survival, and metastasis. Communication between miRNA and carcinogenesis is critical but it still not clear and needs further investigation. The aim of our study is to evaluate the role of miR-210, miR-21, miR-126, as non-invasive diagnostic biomarkers for screening, early detection of CRC, studying their correlation with prognostic variables, and clarifying the roles of miRNAs on HIF-1α-VEGF signaling pathway. The expression of miR-210, miR-21 and miR-126 was performed using qRT-PCR in adenocarcinoma (no?=?35), adenomas (no?=?51), and neoplasm free controls (no?=?101). Serum levels of VEGF and HIF-1α was determined by ELISA Kit. The results show that the expression of miR-210, miR-21, VEGF, HIF-1α was significantly up-regulated while that miRNA-126 was down-regulated in both adenocarcinoma and adenomas compared with controls (p?<?0.001 for each). No significant difference was noted comparing patients with adenocarcinoma and adenomas. The three miRNAs correlated with VEGF, HIF-α. The miR-210 and miR-21 associated with TNM classification and clinical staging of adenocarcinoma (p?<?0.001) and they show high diagnostic value with sensitivity and specificity 88.6%, 90.1% and 91.4%, 95.0% respectively. Our study revealed that circulating miR-210, miR-21 were up-regulated while miR-126 was down-regulated in CRC and adenomas patients, they all correlated with TNM staging and they had high diagnostic value. HIF-1α VEGF signaling pathways regulated by miRNAs played a role in colon cancer initiation. To the best of our knowledge, this is the first study of this miRNAs panel in CRC in our community. These data suggested that these biomarkers could be a potential novel, non-invasive marker for early diagnosis, screening and predicting prognosis of CRC. Understanding the molecular functions by which miRNAs affect cancer and understanding its roles in modulating the signaling output of VEGF might be fruitful in reducing the incidence and slowing the progression of this dark malignancy.

     

Hepatoma-derived growth factor. Significance of amino acid residues 81-100 in cell surface interaction and proliferative activity

Hepatoma-derived growth factor (HDGF) has proliferative, angiogenic, and neurotrophic activity. It plays a putative role in the development and progression of cancer. When expressed in cells, the mitogenic activity of HDGF depends on its nuclear localization, but it also stimulates proliferation when added to the cell culture medium. A cell surface receptor for HDGF has not been identified so far. We investigated the interaction of various purified recombinant HDGF fusion proteins with the cell surface of NIH 3T3 fibroblasts. We showed that binding of a HDGF-beta-galactosidase fusion protein to the cell surface of NIH 3T3 fibroblasts was saturable, occurred with high affinity (K(D) = 14 nm), and had a proliferative effect. We identified a peptide comprising amino acid residues 81-100 within the amino-terminal part of HDGF that bound to the cell surface of NIH 3T3 cells with saturation and affinity values similar to those of HDGF. When added to primary human fibroblasts, this peptide stimulated proliferation. Substitution of a single amino acid (K96A) within this peptide was sufficient to abolish its binding to the cell surface and its proliferative activity. In contrast, when expressed transiently in NIH 3T3 cells, a HDGF-beta-galactosidase fusion protein in which amino acid residues 81-100 were deleted still had proliferative activity, whereas a fusion protein containing only the 81-100 peptide did not. Our results suggest the existence of a plasma membrane-located HDGF receptor for which signaling depends on amino acid residues 81-100 of HDGF. This region differs from the one that has been recently identified to be essential for mitogenic activity depending on the nuclear localization of HDGF. Thus, HDGF exerts its proliferative activity via two different pathways.     

Enzymic synthesis of levan and fructo-oligosaccharides by <Emphasis Type="Italic">Bacillus circulans</Emphasis> and improvement of levansucrase stability by carbohydrate coupling

Bacillus circulans was able to produce extracellular levansucrase using sucrose as carbon source optimally at 35°C. The enzymic synthesis of levan and fructo-oligosaccharides was studied using a 50% ethanol fraction of crude extract. The molecular weight of the synthesized levan was markedly affected by sucrose concentration, the molecular weight of levan decreased with increased sucrose concentration up to 32% whereby fructo-oligosaccharides were isolated. Temperature and the reaction time clearly affected the conversion of fructose to levan with molecular weight values ranging from 10 to 38 kDa. Identification of levan indicated that fructose was the building unit of the levan obtained. Thermal and pH stabilities of B. circulans levansucrase could be improved by enzyme glycosylation using sodium metaperiodate treatment. Chemical modification provides additional points of attachment of the enzyme to the support which offered the modified enzyme greater stabilization than did the free enzyme. The modified enzyme exhibited thermal tolerance up to 50°C, where it retained 88.25% of its activity, while the free enzyme only retained 64.55% of its original activity. The half-life significantly increased from 130 min for the free enzyme to 347 min for the modified enzyme at 50°C, however, it increased from 103 min for the free enzyme to 210 min for the modified enzyme at 60°C. Other properties i.e., the response to some metal ions as well as the ability to convert higher substrate levels and tolerance to an extension of the reaction periods were also improved upon modification. Obviously, the results obtained outlined the conditions leading to the formation of important high or low molecular weight or levan and fructo-oligosaccharides suitable for different industrial applications.     

Antidiabetic Effects of Chamomile Flowers Extract in Obese Mice through Transcriptional Stimulation of Nutrient Sensors of the Peroxisome Proliferator-Activated Receptor (PPAR) Family

Given the significant increases in the incidence of metabolic diseases, efficient strategies for preventing and treating of these common disorders are urgently needed. This includes the development of phytopharmaceutical products or functional foods to prevent or cure metabolic diseases. Plant extracts from edible biomaterial provide a potential resource of structurally diverse molecules that can synergistically interfere with complex disorders. In this study we describe the safe application of ethanolic chamomile (Matricaria recutita) flowers extract (CFE) for the treatment and prevention of type 2 diabetes and associated disorders. We show in vitro that this extract activates in particular nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) and its isotypes. In a cellular context, in human primary adipocytes CFE administration (300 µg/ml) led to specific expression of target genes of PPARγ, whereas in human hepatocytes CFE-induced we detected expression changes of genes that were regulated by PPARα. In vivo treatment of insulin-resistant high-fat diet (HFD)-fed C57BL/6 mice with CFE (200 mg/kg/d) for 6 weeks considerably reduced insulin resistance, glucose intolerance, plasma triacylglycerol, non-esterified fatty acids (NEFA) and LDL/VLDL cholesterol. Co-feeding of lean C57BL/6 mice a HFD with 200 mg/kg/d CFE for 20 weeks showed effective prevention of fatty liver formation and hepatic inflammation, indicating additionally hepatoprotective effects of the extract. Moreover, CFE treatment did not reveal side effects, which have otherwise been associated with strong synthetic PPAR-targeting molecules, such as weight gain, liver disorders, hemodilution or bone cell turnover. Taken together, modulation of PPARs and other factors by chamomile flowers extract has the potential to prevent or treat type 2 diabetes and related disorders.     

Biofertilizers and/or some micronutrients role on wheat plants grown on newly reclaimed soil

Pot experiment was conducted to study the effect of biofertilizers (inoculation with different bacterial isolates), foliar spraying with some micronutrients (Mn, Zn, Fe and Mn+Zn+Fe) and their interaction on growth, physiological parameters and nutrients content of wheat plants grown on reclaimed soil. Pot experiment was conducted in the greenhouse of National Research center, The experimental design was split plot with four replicates. Four biofertilizer treatments (un‐inoculated, Bacillus polymyxa, Azotobacter chroococcum or Azosprillium barasilense) were used and randomly distributed in the main pots. The foliar treatments with micronutrients were randomly distributed in the sub plots. The growth parameters (plant height, leaf area, roots, shoots and whole plant dry weights and number of tillers & leaves per plant); some physiological parameters (soluble sugar %, protein %, polysaccharide %, chl. A+b μg cm^?1 leaf per plant, carotenoids μg g^?1, IAA mg kg^?1 and psll mol DCPIP reduced per mg chl. per h) and nutrient contents (N, P, K, Mg, Mn, Zn and Cu) of wheat plants were significantly increased by inoculating wheat grains with different bacteria as compared with un‐inoculated plants (control). The highest values of all the mentioned parameters were obtained by using Azospirillum brasilense followed by Azotobacter chroococcum and Bacillus polymyxa in decreasing order. Foliar spraying treatments significantly increased the growth parameters, physiological parameters as well as nutrients content of wheat plants as compared with control. Highest values were obtained by using (Mn+Fe+Zn) treatment followed by Zn, Fe and Mn in decreasing order. Micronutrients in wheat plants differed as the foliar treatments were differed, so application of any micronutrient individually significantly increased its content and enhanced the content of other micronutrients in wheat. Interaction between the used biofertilizers and foliar spraying with micronutrients significantly affected all the studied parameters of wheat plants, the highest were obtained by inoculating wheat grains with Azospirillum brasilense and spraying the plants with (Mn+Fe+Zn) treatment, while the lowest values were attained by un‐inoculated grains (control) and spraying the wheat plants with tap water (control). Effective microorganisms in combination with micronutrients could be recommended to farmers to lead higher wheat yield.