Development of Antimicrobial Laser-Induced Photodynamic Therapy Based on Ethylcellulose/Chitosan Nanocomposite with 5,10,15,20-Tetrakis(m-Hydroxyphenyl)porphyrin.

The development of new antimicrobial strategies that act more efficiently than traditional antibiotics is becoming a necessity to combat multidrug-resistant pathogens. Here we report the efficacy of laser-light-irradiated 5,10,15,20-tetrakis(m-hydroxyphenyl)porphyrin (mTHPP) loaded onto an ethylcellulose (EC)/chitosan (Chs) nanocomposite in eradicating multi-drug resistant Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. Surface loading of the ethylcelllose/chitosan composite with mTHPP was carried out and the resulting nanocomposite was fully characterized. The results indicate that the prepared nanocomposite incorporates mTHPP inside, and that the composite acquired an overall positive charge. The incorporation of mTHPP into the nanocomposite enhanced the photo- and thermal stability. Different laser wavelengths (458; 476; 488; 515; 635 nm), powers (5-70 mW), and exposure times (15-45 min) were investigated in the antimicrobial photodynamic therapy (aPDT) experiments, with the best inhibition observed using 635 nm with the mTHPP EC/Chs nanocomposite for C. albicans (59 ± 0.21%), P. aeruginosa (71.7 ± 1.72%), and S. aureus (74.2 ± 1.26%) with illumination of only 15 min. Utilization of higher doses (70 mW) for longer periods achieved more eradication of microbial growth.

Synthesis, in vitro and in vivo antitumor and antiviral activity of novel 1-substituted benzimidazole derivatives.

A novel series of 5-nitro-1H-benzimidazole derivatives substituted at position 1 by heterocyclic rings was synthesized. Cytotoxicity and antiviral activity of the new compounds were tested. Compound 3 was more active than doxorubicin against A-549, HCT-116 and MCF-7. However, compound 3 showed no activity against human liver carcinoma Hep G-2 cell line. Compounds 9 and 17b (E) showed potency near to doxorubicin against the four cell lines. The acute toxicity of compound 9 on liver cancer induced in rats was determined in vivo. Interestingly, it showed restoration activity of liver function and pathology towards normal as compared to the cancer-bearing rats induced by DENA. Compounds 17a (Z), 17b (E) and 18a (Z) were the most promising compounds for their antiviral activity against rotavirus Wa strain.

Part I. Synthesis, biological evaluation and docking studies of new 2-furylbenzimidazoles as antiangiogenic agents.

2-(2-Furyl)-1H-benzimidazoles 3-11 were synthesized and tested for their in vitro VEGF inhibition in MCF-7 cancer cell line. Compound 5a was more potent than Tamoxifen, and compounds 3b, 5a, 5c, 6b, 7a and 10 showed promising potency. Furthermore, compounds (6b, 7a and 10) showed remarkable selective inhibition of COX-2 enzyme close to that of Celecoxcib. Additionally, docking studies were performed using AutoDock 4.2 into the VEGFR2 kinase. Significant correlation exists between the biological activity (IC50 and %VEGF inhibition) against MCF-7 cell line and the molecular docking results (Ki and ΔGb) with correlation coefficients (R(2)) of 0.5513 and 0.4623 respectively. Accordingly, most of the synthesized 2-(2-furyl)-1H-benzimidazoles showed strong antiangiogenic activity against VEGFR2 kinase.

Synthesis, biological evaluation, and docking studies of new 2-furylbenzimidazoles as anti-angiogenic agents: part II.

The 2-(5-methyl-2-furyl)-1H-benzimidazole moiety has shown promising activity against vascular endothelial growth factor (VEGF)-induced angiogenesis. In part I of this study, we have synthesized new analogs and tested their anti-angiogenic potentials. Here, we continue our previous study with different new analogs. Some compounds show promising cytotoxic activity against the human breast cancer cell line MCF-7, with IC50 in the range of 7.80-13.90 µg/mL, and exhibited remarkable in vitro inhibition against VEGF in the MCF-7 cancer cell line, with 95-98% of inhibition in comparison to tamoxifen as reference (IC50: 8.00 µg/mL, % of inhibition = 98%). Additionally, a molecular docking study was carried out to gain insight into plausible binding modes and to understand the structure-activity relationships of the synthesized compounds.

Synthesis and docking studies of novel antitumor benzimidazoles.

In this work, the benzimidazole-pyrrole conjugates 6a-h and benzimidazole-tetracycles conjugates 12-14 were prepared. The cytotoxicity of the compounds 3, 4a-h, 6a-h, 8, 10 and 12-14 was tested against lung cancer cell line A549. Compound 6b exhibited higher activity than the bis-benzoxazole natural product (UK-1), the standard. The tested 4g,h, 6a-h, 10 and 12-14 exhibited remarkable cytotoxicity activity against breast cancer cell line MCF-7 with higher activity than tamoxifen. Furthermore, compound 4h was found to be also more potent than doxurubicin. The antitumor promotion activity of synthesized compounds 4g,h, 6a-h, 10 and 12-14 has been estimated by studying their possible inhibitory effects on EBV-EA activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds, the inhibitory activities of compounds 8, 13 and 14 demonstrated strong inhibitory effects on the Epstein-Barr virus early antigen (EBV-EA) activation without showing any cytotoxicity on the Raji cells and their effects being stronger than that of a representative control, oleanolic acid. Moreover, the molecular docking of the new compounds into plasminogen activator (uPA) receptor has been in correlation with the antitumor activity. All synthesized compounds 3, 4a-h, 6a-h, 8, 10 and 12-14 were docked into same groove of the binding site of the native co-crystalized (4-iodobenzo[b]thiophene-2-carboxamidine) ligand (PDB code:1c5x) for activity explaination. Compounds 4h, 6b and 13, giving the best docking results, were further studied to estimate their effect on the level of uPA using AssayMax human urokinase (uPA) ELISA kit. In case of A549 cell line, compound 6 exhibited similar activity to MMC, and for MCF-7 cell line, compound 4h exhibited similar activity to doxorubicin, in inhibiting the expression of uPA.