Preclinical safety assessment of Angelica acutiloba using a 13-week repeated dose oral toxicity study in rats / 한국실험동물학회지

Angelica acutiloba (AA), a Japanese species of Danggui, has been used worldwide as a traditional herbal medicine with several bioactivities including anti-diabetic, anti-allergic, anti-inflammatory, anti-tumor, and anti-obesity. However, there is lack of toxicological data available to evaluate potential long-term toxicity and the no-observed-adverse-effect level (NOAEL) of AA extract in accordance with the test guidelines published by the Organization for Economic Cooperation and Development. In the 14-day repeat-dose toxicity study, no adverse effects on mortality, body weight change, clinical signs, and organ weights was found following repeat oral administration to rats for 14 days (125, 250, 500, 1000, and 2000 mg/kg body weight), leading that 2000 mg/kg is the highest recommended dose of AA extract for the 13-week repeat-dose oral toxicity study. In the 13-week repeat-dose oral toxicity study, the AA extract was orally administered to groups of rats for 13 weeks (125, 250, 500, 1000, and 2000 mg/kg body weight) to compare between control and AA extract groups. The administration of AA extract did not produce mortality or remarkable clinical signs during this 13-week study. And, the data revealed that there were no significant differences in food/water consumption, body weight, hematological parameters, clinical chemistry parameters, gross macroscopic findings, organ weight and histopathology in comparison to the control group. On the basis of these results, the subchronic NOAEL of the AA extract was more than 2000 mg/kg/day when tested in rats. And, the AA extract is considered safe to use orally as a traditional herbal medicine.

Evaluation of in vitro and in vivo genotoxicity of Angelica acutiloba in a standard battery of assays / 한국실험동물학회지

Among three representative species of Angelica found in Asian countries, including Korea, China, and Japan, Angelica acutiloba (AA) has been used as traditional herbal medicine with antitumor, anti-inflammatory, anti-obesity, and anti-diabetes activities. In this study, the potential genotoxicity and mutagenicity of the AA extract were examined in a battery of in vitro and in vivo tests (bacterial reverse mutation assay, in vitro chromosomal aberrations assay, and in vivo micronucleus assay) in accordance with the test guidelines for toxicity testing developed by the Organization for Economic Cooperation and Development. Upon testing in the bacterial mutation assay (Ames test) using five Salmonella typhimurium TA98, TA100, TA102, TA1535 and TA1537, no significant increase the number of revertant colonies in the metabolic activation system and non-activation system was noted in the AA extract groups. Also, in the chromosome aberration test, the AA extract did not cause chromosomal aberration with or without metabolic activation by S9 mix. A bone marrow micronucleus test of mice demonstrated that the incidence of micronucleated polychromatic erythrocytes in the AA extract groups (500, 1000 and 2000 mg/kg BW) was equivalent to that of the negative control group. Based on these results from a standard battery of assays, the AA extract was concluded to have no genotoxic at the proper dose.

Optimal salt concentration of vehicle for plasmid DNA enhances gene transfer mediated by electroporation

In vivo electroporation has emerged as a leading technology for developing nonviral gene therapies, and the various technical parameters governing electroporation efficiency have been optimized by both theoretical and experimental analysis. However, most electroporation parameters focused on the electric conditions and the preferred vehicle for plasmid DNA injections has been normal saline. We hypothesized that salts in vehicle for plasmid DNA must affect the efficiency of DNA transfer because cations would alter ionic atmosphere, ionic strength, and conductivity of their medium. Here, we show that half saline (71 mM) is an optimal vehicle for in vivo electroporation of naked DNA in skeletal muscle. With various salt concentrations, two reporter genes, luciferase and beta-galactosidase were injected intramuscularly under our optimal electric condition (125 V/cm, 4 pulses x 2 times, 50 ms, 1 Hz). Exact salt concentrations of DNA vehicle were measured by the inductively coupled plasma-atomic emission spectrometer (ICP-AES) and the conductivity change in the tissue induced by the salt in the medium was measured by Low-Frequency (LF) Impedance Analyzer. Luciferase expression in-creased as cation concentration of vehicle dec-reased and this result can be visualized by X-Gal staining. However, at lower salt concentration, transfection efficiency was diminished because the hypoosmotic stress and electrical injury by low conductivity induced myofiber damage. At optimal salt concentration (71 mM), we observed a 3-fold average increase in luciferase expression in comparison with the normal saline condition (p < 0.01). These results provide a valuable experimental parameter for in vivo gene therapy mediated by electroporation.

Optimal salt concentration of vehicle for plasmid DNA enhances gene transfer mediated by electroporation

In vivo electroporation has emerged as a leading technology for developing nonviral gene therapies, and the various technical parameters governing electroporation efficiency have been optimized by both theoretical and experimental analysis. However, most electroporation parameters focused on the electric conditions and the preferred vehicle for plasmid DNA injections has been normal saline. We hypothesized that salts in vehicle for plasmid DNA must affect the efficiency of DNA transfer because cations would alter ionic atmosphere, ionic strength, and conductivity of their medium. Here, we show that half saline (71 mM) is an optimal vehicle for in vivo electroporation of naked DNA in skeletal muscle. With various salt concentrations, two reporter genes, luciferase and beta-galactosidase were injected intramuscularly under our optimal electric condition (125 V/cm, 4 pulses x 2 times, 50 ms, 1 Hz). Exact salt concentrations of DNA vehicle were measured by the inductively coupled plasma-atomic emission spectrometer (ICP-AES) and the conductivity change in the tissue induced by the salt in the medium was measured by Low-Frequency (LF) Impedance Analyzer. Luciferase expression in-creased as cation concentration of vehicle dec-reased and this result can be visualized by X-Gal staining. However, at lower salt concentration, transfection efficiency was diminished because the hypoosmotic stress and electrical injury by low conductivity induced myofiber damage. At optimal salt concentration (71 mM), we observed a 3-fold average increase in luciferase expression in comparison with the normal saline condition (p < 0.01). These results provide a valuable experimental parameter for in vivo gene therapy mediated by electroporation.