Synthesis and Biological Evaluation of Structurally Diverse Benzimidazole Scaffolds as Potential Chemotherapeutic Agents.

BACKGROUND AND OBJECTIVE: Drug resistance and adverse effects are immense healthcare challenges in cancer therapy. Benzimidazole ring-based small molecules have been effective anticancer agents in drug development. In an effort to develop novel chemotherapeutics, we synthesized and assessed the anticancer and antibacterial activities of a small library of structurally unique benzimidazoles. METHODS: The benzimidazoles were derived from indole, N-alkyl indole, fatty acid, and alpha-amino acid scaffolds providing a panel of diverse structures. The compounds were tested in three different cancer cell lines for cytotoxicity: HepG2 (human hepatocellular carcinoma), HeLa (human cervical carcinoma), and A549 (human lung carcinoma). Mechanism of cell death induced by benzimidazoles was evaluated using fluorescent dye-based apoptosis-necrosis assay, immunoblotting for active caspases, topoisomerase-II activity assay, and cell cycle assay. RESULTS: Cell viability testing revealed that indole- and fatty acid-based benzimidazoles were most potent followed by the amino acid derivatives. Many compounds induced cytotoxicity in a concentration-dependent manner with cellular cytotoxicity (CC50) <20µM in the cell lines tested. Most compounds exhibited cytotoxicity via apoptosis through the intrinsic pathway. Inhibition of topoisomerase activity and cell cycle alterations were not the primary mechanisms of cytotoxicity. In addition, several compounds showed promising activity against S. aureus and S. epidermidis (Minimum Inhibitory Concentration (MIC) of as low as 0.04µmol/mL). CONCLUSION: The reported benzimidazole derivatives possess promising anticancer and antibacterial properties. Additionally, we discovered apoptosis to be the primary mechanism for cancer cell death induced by the tested benzimidazoles. Our findings suggest that further development of these scaffolds could provide drug leads towards new chemotherapeutics.

Effects of moderate-dose omega-3 fish oil on cardiovascular risk factors and mood after ischemic stroke: a randomized, controlled trial.

BACKGROUND AND PURPOSE: Fish-derived omega-3 fatty acids have long been associated with cardiovascular protection. In this trial, we assessed whether treatment with a guideline-recommended moderate-dose fish oil supplement could improve cardiovascular biomarkers, mood- and health-related quality of life in patients with ischemic stroke. METHODS: Patients with CT-confirmed stroke were randomized to 3 g/day encapsulated fish oil containing approximately 1.2 g total omega-3 (0.7 g docosahexaenoic acid; 0.3 g eicosapentaenoic acid) or placebo oil (combination palm and soy) taken daily over 12 weeks. Serum triglycerides, total cholesterol and associated lipoproteins, selected inflammatory and hemostatic markers, mood, and health-related quality of life were assessed at baseline and follow-up. The primary outcome was change in triglycerides. Compliance was assessed by capsule count and serum phospholipid omega-3 levels (Australian Clinical Trials Registration: ACTRN12605000207617). RESULTS: One hundred two patients were randomized to fish oil or placebo. Intention-to-treat and per-protocol (>85% compliance) analyses showed no significant effect of fish oil treatment on any lipid, inflammatory, hemostatic, or composite mood parameters measured. Adherence to treatment based on pill count was good (89%) reflected by increased serum docosahexanoic acid (P<0.001) and eicosapentaenoic acid (P=0.0006) in the fish oil group. Analysis of oil composition, however, showed some degradation and potentially adverse oxidation products at the end of the study. CONCLUSIONS: There was no effect of 12 weeks of treatment with moderate-dose fish oil supplements on cardiovascular biomarkers or mood in patients with ischemic stroke. It is possible that insufficient dose, short duration of treatment, and/or oxidation of the fish oils may have influenced these outcomes.