Bromelain and ficin proteolytic effects on gliadin cytotoxicity and expression of genes involved in cell-tight junctions in Caco-2 cells.

Enzyme therapy for celiac disease (CeD), which digests gliadin into non-immunogenic and non-toxic peptides, can be an appropriate treatment option for CeD. Here, we have investigated the effectiveness of bromelain and ficin on gliadin digestion using in vitro, such as SDS-PAGE, HPLC, and circular dichroism (CD). Furthermore, the cytotoxicity of gliadin and 19-mer peptide before and after digestion with these enzymes was evaluated using the MTT assay in the Caco-2 cell line. Finally, we examined the effect of these treatments along with Larazotide Acetate on the expression of genes involved in cell-tight junctions, such as Occludin, Claudin 3, tight junction protein-1, and Zonulin in the Caco-2 cell line. Our study demonstrated bromelain and ficin digestion effects on the commercial and wheat-extracted gliadin by SDS-PAGE, HPLC, and CD. Also, the cytotoxicity results on Caco-2 showed that toxicity of the gliadin and synthetic 19-mer peptide was decreased by adding bromelain and ficin. Furthermore, the proteolytic effects of bromelain and ficin on gliadin indicated the expression of genes involved in cell-tight junctions was improved. This study confirms that bromelain and ficin mixture could be effective in improving the symptoms of CeD.

Alignment-based design and synthesis of new antimicrobial Aurein-derived peptides with improved activity against Gram-negative bacteria and evaluation of their toxicity on human cells.

Considering the worldwide increasing prevalence of resistance to traditional antibiotics, it is necessary to find new antibiotics to deal with this issue. Recently, antimicrobial peptides (AMPs) have been proposed as new antimicrobial agents. Aureins are a family of AMPs that are isolated from Green and Golden Bell Frogs. These peptides have a favorable antibacterial activity against Gram-positive bacteria. We designed two peptides derived from natural Aurein enjoying alignment-based design method. After synthesis of the peptides, their secondary structure was checked by circular dichroism. Consequently, the antibacterial effects of these peptides were investigated by determining the minimum inhibitory concentration (MIC) and bactericidal concentration. Eventually, the toxicity of these peptides was determined by MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay on normal human skin cells (Hu02 cell line). Natural Aurein1.2 was used as a natural control to compare the properties in all stages. The results indicated that these new peptides had medium-upward antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis (MIC of 8-64 µg/mL) and weak bactericidal activity against Staphylococcus aureus (MIC of 128-256 µg/mL). Also, MTT assays results showed that AureinN2 is less toxic than AureinN1 and Aurein1.2. Toxicity of AureinN2 for Hu02 cell lines was between 20 and 40% at the concentration of 8-500 µg/mL. In this study, we were able to improve antimicrobial activity of two synthetic derivatives of the Aurein family against Gram-negative bacteria by using machine-learning algorithm and other in silico methods.

Cheminformatics-based selection and synergism of herbal extracts with anticancer agents on drug resistance tumor cells-ACHN and A2780/cp cell lines.

The treatment of cancer usually involves lethal effect on normal body cells as side effects. Cheminformatics methodology can play a significant role in biomed/clinical scientific research. Similarity searching is a standard cheminformatics tool in drug discovery area and database design. In this study, five novel herbal extracts in combination with doxorubicin and cisplatin have been used to sensitize ACHN and A2780/cp cells. These herbal extracts have been selected on the basis of novel cheminformatics methodology and assayed for the first time. The findings confirmed predicted outcomes from the in silico research and the results introduced may bring to use the effects of these herbs in reversing of multidrug resistance (MDR) phenomenon.

Cheminformatics based selection and cytotoxic effects of herbal extracts.

Bioinformatics and traditional medicine can be used in discovery and design of novel candidate drugs to efficient cancer chemotherapy. In this study, similarity search tools employed to screen and introduce novel herbs with antitumor property. Several novel herbs have been selected by using logical computational algorithms and assayed on six cancerous cell lines. Complementary assays involved hemolytic and antifungal MIC tests have been performed to determine selectivity and their biocompatibility with RBC of herbal extracts. Final findings may point at selective activity of herbal extracts Rheum ribes, Ficus bengalensis, Morus alba, Musa sapientum, Arnebia decumbens, Citrus limon, Fraxinus excelsior, Rumex acetosella, Arnebia echioides in inducing cytotoxicity on cancerous cell lines. In the present research, in vitro results confirmed predicted findings from our in silico work. Complementary assays including antifungal MIC and hemolytic tests were carried out also to determine selectivity of herbal extracts. Findings resulted from hemolytic test showed that candidate herbal extracts did not induce hemolysis similar to negative control, also antifungal test results indicated that six herbal extracts had antifungal activity in concentration of 250 microg/ml.