Antibacterial efficacy of lytic phages against multidrug-resistant Pseudomonas aeruginosa infections in bacteraemia mice models.

BACKGROUND: Pseudomonas aeruginosa is an opportunistic pathogen that can cause a variety of infections in humans, such as burn wound infections and infections of the lungs, the bloodstream and surgical site infections. Nosocomial spread is often concurrent with high degrees of antibiotic resistance. Such resistant strains are difficult to treat, and in some cases, even reserved antibiotics are ineffective. A particularly promising therapy to combat infections of resistant bacteria is the deployment of bacteriophages, known as phage therapy. In this work, we evaluated the in vivo efficacy of two Pseudomonas phages in bacteremia mice models. For this study, non-neutropenic mice (BalB/C) were infected with P. aeruginosa AB030 strain and treated using two bacteriophages, AP025 and AP006. RESULTS: The results showed that a single dose of phages at higher concentrations, bacteria: phage at 1:10 and 1:100 were effective in eliminating the bloodstream infection and achieving 100% mice survival. CONCLUSION: This study highlights the efficacy of using a single dose of phages to restore mice from bacteremia.

Safety Assessment of Ubiquinol Acetate: Subchronic Toxicity and Genotoxicity Studies.

Coenzyme Q10 (CoQ10) is a lipid soluble, endogenous antioxidant present at highest levels in the heart followed by the kidney and liver. The reduced CoQ10 ubiquinol is well known for its chemical instability and low bioavailability. The present study was designed to synthesize ubiquinol acetate, which is more stable and biologically active, and further evaluate its safety and genotoxic potential. Synthesized ubiquinol acetate showed better stability than that of ubiquinol at the end of 3 months. In vitro genotoxicity studies (AMES test, in vitro micronucleus and chromosomal aberration) showed ubiquinol acetate as nongenotoxic with no clastogenic or aneugenic effects at high dose of 5000 and 62.5 µg/mL, respectively. In subchronic toxicity study, ubiquinol acetate was administered orally to Sprague Dawley rats at 150, 300, and 600 mg/kg/day for 90 days. No treatment related adverse effects were observed in males at 600 mg/kg/day; however, females showed treatment related increase in AST and ALT with small focal irregular white-yellow spots in liver on gross necropsy examination. Histopathological evaluation revealed hepatocellular necrosis in high dose females which was considered as adverse. Based on the results, the No-Observed-Adverse-Effect Level (NOAEL) of ubiquinol acetate in males and females was determined as 600 and 300 mg/kg/day, respectively.

Toxicologic evaluation of Dichrostachys glomerata extract: subchronic study in rats and genotoxicity tests.

In western Cameroon, edible fruits and seeds from the plant Dichrostachys glomerata are commonly used as spices. Extract from the fruit pods has been reported as a good natural source of antioxidants and may provide health benefits. The objective of the present study was to investigate potential adverse effects, if any, of D. glomerata fruit pod extract (Dyglomera™) in a subchronic toxicity study and in genotoxicity studies. In the toxicity study, Sprague Dawley rats (20/sex/group) were gavaged with D. glomerata extract at dose levels of 0, 100, 1000 and 2500 mg/kg body weight (bw)/day for 90-days. Dyglomera™ administration did not result in mortality or show treatmentrelated changes in clinical signs of toxicity, body weights, body weight gain or feed consumption. Similarly, no toxicologically significant treatment-related changes in hematological, clinical chemistry, urine analysis parameters, and organ weights were noted. Macroscopic and microscopic examinations did not reveal treatment-related abnormalities. Mutagenic and clastogenic potentials as evaluated by Ames assay, in vitro and in vivo chromosomal aberration test and in vivo micronucleus test did not reveal any genotoxicity of the extract. The results of subchronic toxicity study supports the no-observed-adverse-effect level (NOAEL) for D. glomerata extract as 2500 mg/kg bw/day, the highest dose tested.