The objective of this study was to evaluate the acute and subacute toxicity (28 days) of the ethanol extract of Z. zerumbet rhizomes (EEZZ) via the oral route in Wistar rats of both sexes. In the acute toxicity study, Wistar rats were administered a single dose of 15 g kg−1 of body weight by gavage, and were monitored for 14 days. EEZZ did not produce any toxic signs or deaths; the 50% lethal dose must be higher than 15 g kg−1. In the subchronic toxicity study, EEZZ was administered by gavage at doses of 1000, 2000 and 3000 mg/kg daily for 4 weeks to Wistar rats. The subacute treatment with EEZZ did not alter either the body weight gain or the food and water consumption. The hematological and biochemical analysis did not show significant differences in any of the parameters examined in female or male groups. Necropsy and histopathological examination, did not reveal any remarkable and treatment related changes. A no-observed adverse-effect level for EEZZ is 3000 mg kg−1 for rats under the conditions of this study. Hence, consumption of EEZZ for various medicinal purposes is safe.
Acute and subchronic toxicities of Chantaleela recipe were studied in both male and female rats. Oral administration of the extract at a single dose of 5,000 mg/kg body weight (5 females, 5 males) did not produce signs of toxicity, behavioral changes, mortality or differences on gross appearance of internal organs. The subchronic toxicity was determined by oral feeding the test substance at the doses of 600, 1,200 and 2,400 mg/kg body weight for 90 days (10 females, 10 males). No signs of abnormalities were observed in the test groups as compared to the controls. The test and control groups (on the 90th day) and the satellite group (on the 118th day) were analyzed by measuring their final body and organ weights, taking necropsy, and examining hematological parameters, blood clinical chemistry and histopathology features. The results suggest that Chantaleela recipe did not cause acute or subchronic oral toxicities to female and male rats.
Acute toxicity; Subchronic toxicity; Chantaleela recipe
Ocimum basilicum L. is widely used in folk medicine of many countries including . Both O.
basilicum and its oil extract have received considerable attention for their potential medicinal properties, but there are a few reports about possible toxicity of this plant. Therefore, in the present study, acute and subchronic toxicity of O. basilicum hydroalcohlic extract have been evaluated in Wistar rats.
Materials and Methods
For the acute toxicity assessment, five groups of 10 animals (5 male, 5 female) received four different single dose of extract orally, the animals were, then, kept under observation for 14 days. For subchronic toxicity, the animals were divided into four groups (5 male, 5 female) and were gavaged daily by 50, 200 and 500 mg/kg of extract. Mortality, clinical signs, body weight changes, food and water consumption, and hematological and biochemical parameters were monitored during the study period. On the 45th day, animals were sacrificed and gross findings, weight of liver and left kidney and liver histological markers were assessed.
The results of acute study indicated that LD50 of O. basilicum is higher than 5 mg/kg. In subchronic study, no adverse effects were observed on serum parameters in male and female rats. The hematological results showed a reduction in the hematocrit, platelets and RBC in both sexes. No abnormalities were observed in other parameters.
Based on the results of this study, present data suggest that hematologic system could serve as a target organ in oral toxicity of this plant.
Acute toxicity; Ocimum basilicum; Rats; Subchronic toxicity
The safety of Zigbir®, a polyherbal formulation intended for use as food supplement, was evaluated in Sprague-Dawley rats treated orally at the dose of 2000 mg/kg in acute and at 250, 500, and 1000 mg/kg for 90 days in subchronic toxicity study. The median lethal dose of Zigbir® was found to be more than 2000 mg/kg, and fourteen-day repeated dose toxicity study revealed it to be safe up to 1000 mg/kg. The subchronic study did not show any mortality or treatment-related adverse clinical signs. The treated animals exhibited normal feed intake and comparable body weight gain except for a decrease in females of 500 and 1000 mg/kg groups. Ocular examination revealed no abnormalities. Further, Zigbir® administration in rats did not induce any major changes in urinalysis, hematological, and biochemical evaluations except for minor alterations in few parameters at different dose levels. Gross and histopathological findings did not show any lesions attributable to Zigbir® administration. The no observed effect level of Zigbir® was found to be 500 and 250 mg/kg in male and female Sprague-Dawley rats.
Acute and subchronic toxicities of Tud-Rak-Ka-Sai-Puu (TR) recipe were studied in male and female rats. After 14 days of a single oral administration of test substance (5,000 mg/kg body weight), measurement of the body and organs weights, necropsy and health monitoring were performed. No signs and differences in the weights and behavior were observed relative to the control rats, suggesting that TR recipe in the dose of 5,000 mg/kg body weight does not produce acute toxicity. The subchronic toxicity was determined by oral feeding in male and female rats daily with the test substance at 2, 20, 200 and 2,000 mg/kg body weight for 90 days. No defects of animal behavior were observed in the test groups. Both test and control groups (on the 90th day) as well as the satellite group (on the 118th day) were analyzed by measuring their final body and organ weights, taking necropsy, and examining hematology, blood clinical chemistry, and microanatomy. These results together with the information of signs, behavior and health monitoring can lead to a conclusion that an oral administration of TR recipe at 2, 20, 200 and 2,000 mg/kg body weight for 90 days did not cause subchronic toxicity.
Acute toxicity; Subchronic toxicity; Tud-Rak-Ka-Sai-Puu Recipe
Ficus deltoidea leaves have been used in traditional medicine in Southeast Asia to treat diabetes, inflammation, diarrhea, and infections. The present study was conducted to assess the genotoxicity and acute and subchronic toxicity of a standardized methanol extract of F. deltoidea leaves.
Sprague Dawley rats were orally treated with five different single doses of the extract and screened for signs of toxicity for two weeks after administration. In the subchronic study, three different doses of the extract were administered for 28 days. Mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histological parameters were monitored during the study. Genotoxicity was assessed using the Ames test with the TA98 and TA100 Salmonella typhimurium strains. Phytochemical standardization was performed using a colorimeter and high-performance liquid chromatography. Heavy metal detection was performed using an atomic absorption spectrometer.
The acute toxicity study showed that the LD50 of the extract was greater than 5000 mg/kg. In the subchronic toxicity study, there were no significant adverse effects on food consumption, body weight, organ weights, mortality, clinical chemistry, hematology, gross pathology, or histopathology. However, a dose-dependent increase in the serum urea level was observed. The Ames test revealed that the extract did not have any potential to induce gene mutations in S. typhimurium, either in the presence or absence of S9 activation. Phytochemical analysis of the extract revealed high contents of phenolics, flavonoids, and tannins. High-performance liquid chromatography analysis revealed high levels of vitexin and isovitexin in the extract, and the levels of heavy metals were below the toxic levels.
The no-observed adverse effect level of F. deltoidea in rats was determined to be 2500 mg/kg.
Ficus deltoidea; Oral Toxicity; OECD; Genotoxicity; Isovitexin; Vitexin
Menaquinone-7 (MK-7) is part of a family of vitamin K that are essential co-factors for the enzyme γ-glutamyl carboxylase, which is involved in the activation of γ-carboxy glutamate (Gla) proteins in the body. Gla proteins are important for normal blood coagulation and normality of bones and arteries. The objective of this study was to examine the potential toxicity of synthetic MK-7 in BomTac:NMRI mice and in Sprague-Dawley rats. In an acute oral toxicity test, mice were administered a single oral dose of 2000 mg/kg body weight (limit dose) and no toxicity was observed during the 14-day observation period. In the subchronic oral toxicity test in rats, animals were administered MK-7 for 90 days by gavage at the following doses: 0 (vehicle control, corn oil), 2.5, 5, and 10 mg/kg body weight/day. All generated data, including clinical observations, ophthalmology, clinical pathology, gross necropsy, and histopathology, revealed no compound-related toxicity in rats. Any statistically significant findings in clinical pathology parameters and/or organ weights noted were considered to be within normal biological variability. Therefore, under the conditions of this experiment, the median lethal dose (LD50) of MK-7 after a single oral administration in mice was determined to be greater than the limit dose level of 2000 mg/kg body weight. The no observed adverse effect level (NOAEL) of MK-7, when administered orally to rats for 90 days, was considered to be equal to 10 mg/kg body weight/day, the highest dose tested, based on lack of toxicity during the 90-day study period.
Menaquinone-7; acute oral toxicity; 90-day oral subchronic toxicity study; histopathology
Soshiho-tang (Xiao-chai-hu-tang in Chinese and Sho-saiko-to in Japanese) has been widely used for its various pharmacological effects, which include anti-inflammatory, antioxidant, antihepatic fibrosis, and antitumor properties. To evaluate the safety of Soshiho-tang water extract (SST), we tested its subchronic toxicity in male and female Crl:CD (SD) rats. Rats were orally treated with four different doses (0, 500, 1000, and 2000 mg/kg/day) of SST administered for 13 weeks. Mortality, clinical signs, body weight changes, food and water consumption changes, ophthalmology, urinalysis, hematological and biochemical parameters, gross findings, organ weights, and histological markers were monitored during the study. The SST treatment did not result in any toxicologically significant changes in mortality, clinical signs, body weights, food and water consumption, ophthalmoscopy, urinalysis, hematological and serum biochemical parameters, gross findings, organ weights, or histopathology. Histological analysis did not show any liver or kidney alteration. We concluded that the 13-week repeated oral administration of SST did not cause any adverse effects in rats at dosage levels of ≤2000 mg/kg/day. Under these experimental conditions, the no-observed-adverse-effect level was concluded to be 2000 mg/kg/day for both sexes.
Chloral hydrate has been found in our drinking water supplies at levels up to 5 micrograms/1. The purpose of this study was to evalute the acute and subchronic toxicology of chloral hydrate in the random-bred CD-1 mouse, to provide data for risk assessment. The acute oral LD50 of this compound was 1442 and 1265 mg/kg in male and female mice, respectively. Acute toxicity appeared to be related to depression of the central nervous system. Fourteen-day exposure by gavage in male mice at doses 1/10 and 1/100 the LD50 caused an increase in liver weight and a decrease in spleen weight at the highest dose level. Based on the data derived from 14 days of exposure, a 90-day study was performed. The compound was delivered via the drinking water; levels of the compound delivered per day were equivalent to those dosed in the 14-day study. The target organ in both sexes appeared to be the liver, with the males most affected. Male mice demonstrated a dose-related hepatomegaly accompanied by significant changes in serum chemistries and hepatic microsomal parameters. The females did not demonstrate the hepatomegaly observed in males, but did show alterations in hepatic microsomal parameters. No other significant toxicological changes were observed in either sex following 90 days of exposure.
To characterize the subchronic oral toxicity of resveratrol, CD rats received daily gavage doses of 0, 200, 400, or 1000 mg resveratrol/kg/day, and beagle dogs received daily capsule doses of 0, 200, 600, or 1200 mg resveratrol/kg/day for 90 days. Resveratrol induced only minimal toxicity, consisting of dose-related reductions in body weight gain in female rats and both sexes of dogs, and a statistically significant increase in bilirubin levels in rats at the 1000 mg/kg/day dose. Clinical observations, hematology, ophthalmology, neurotoxicity evaluations (functional observational batteries), organ weights, and gross pathology provided no biologically significant evidence of resveratrol toxicity in either species. In rats, the high dose of resveratrol reduced the incidence of cardiomyopathy; no other microscopic changes were seen. Histopathologic changes in dogs were limited to minimal inflammatory infiltrates in the kidney and urinary bladder, which were not considered toxicologically significant. A cardiovascular safety pharmacology (telemetry) study in dogs revealed no evidence of resveratrol toxicity. Based on body weight effects, the No Observed Adverse Effect Level (NOAEL) for resveratrol was 200 mg/kg/day in rats and 600 mg/kg/day in dogs. The apparent cardioprotective activity of resveratrol in rats demonstrates that its potentially beneficial activities may extend beyond efficacy in cancer prevention.
This study was conducted in order to obtain information concerning the health hazards that may result from a 13 week inhalation exposure of n-pentane in Sprague-Dawley rats.
This study was conducted in accordance with the Organization for Economic Co-operation and Development (OECD) guidelines for the testing of chemicals No. 413 'Subchronic inhalation toxicity: 90-day study (as revised in 2009)'. The rats were divided into 4 groups (10 male and 10 female rats in each group), and were exposed to 0, 340, 1,530, and 6,885 ppm n-pentane in each exposure chamber for 6 hour/day, 5 days/week, for 13 weeks. All of the rats were sacrificed at the end of the treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, locomotion activity, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were assessed.
During the period of testing, there were no treatment related effects on the clinical findings, body weight, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, relative organ weight, and histopathological findings.
The no-observable-adverse-effect level (NOAEL) of n-pentane is evaluated as being more than 6,885 ppm (20.3 mg/L) in both male and female rats. n-pentane was not a classified specific target organ toxicity in the globally harmonized classification system (GHS).
n-Pentane; Subchronic inhalation toxicity; Sprague-Dawley rats; Globally harmonized classification system
Toxicity tests of 95% ethanol extract of the root of Antidesma acidum were studied in male and female rats. The oral acute toxicity test at 5,000 mg/kg revealed that the ethanol extract did not produce toxic effects on signs, general behavious, mortality and gross appearance of internal organs of rats. Furthermore, the oral sub-acute toxicity test at the dose of 1,000 mg/kg/day displayed no significant changes in body and internal organs' weights, normal hematological and clinical blood chemistry values. Histological examination also showed normal architecture of all internal organs. In conclusion, the ethanol extract of Antidesma acidum did not produce any toxicity in oral acute and suba-cute toxicity studies.
Antidesma acidum; Acute toxicity; Subacute toxicity
Androstenedione was marketed as a dietary supplement to increase muscle mass during training. Due to concern over long-term use, the NTP evaluated the subchronic and chronic toxicity and carcinogenicity of androstenedione in male and female F344/N rats and B6C3F1 mice. In subchronic studies, dose limiting effects were not observed. A chronic (two-year) exposure by gavage at 10, 20, or 50 mg/kg in rats and male mice, and 2, 10, or 50 mg/kg in female mice (50 mg/kg, maximum feasible dose) was conducted. Increased incidences of lung alveolar/bronchiolar adenoma and carcinoma occurred in the 20 mg/kg male rats and increases in mononuclear cell leukemia occurred in the 20 and 50 mg/kg female rats, which may have been related to androstenedione administration. In male and female mice, androstenedione was carcinogenic based upon a significant increase in hepatocellular tumors. A marginal increase in pancreatic islet cell adenomas in male (50 mg/kg) and female (2, 10, 50 mg/kg) mice was considered to be related to androstenedione administration. Interestingly, incidences of male rat Leydig cell adenomas and female rat mammary gland fibroadenomas decreased. In conclusion, androstenedione was determined to be carcinogenic in male and female mice, and may have been carcinogenic in rats.
Androstenedione; Rat; Mice; Cancer; Two-Year Bioassay; Toxicity
The present study investigated the potential subacute toxicity of 1,4-dichlorobutane by a 4-week repeated oral dose in Sprague-Dawley rats. The test article was administered once daily by gavage to male rats at dose levels of 0, 100, 300, and 1,000 mg/kg/day for 4 weeks. All rats were sacrificed at the end of the treatment period. During the test period, clinical signs, mortality, body weight, hematology, serum biochemistry, gross findings, and organ weight were examined. At 1,000 mg/kg/day, an increase in the clinical signs and weights of the liver and kidneys was observed in the male rats. Serum biochemical investigations revealed an increase in alanine aminotransferase, alkaline phosphatase, total cholesterol, total bilirubin, phospholipids, blood urea nitrogen, and gamma glutamyl transferase levels. There were no treatment-related adverse effects in the low and middle-dose groups. In the present experimental conditions, the target organs were determined to be liver and kidney. The no-observed-adverse-effect level was considered to be 300 mg/kg/day in rats.
1,4-Dichlorobutane; subacute toxicity; target organ; no-observed-adverse-effect level
Echinophora platyloba DC is a widely used herbal medicine and food seasoning in Iran. It is claimed to exert antimicrobial, antifungal, and antispasmodic effects. Despite the prevalent use of this plant as a food and medicine, there are no reports on its possible toxic effects. To evaluate the safety of E. platyloba, we tested its acute and sub-chronic toxicity in male and female Wistar rats.
Rats were orally treated with four different single doses of E. platyloba total extract and screened for signs of toxicity two weeks after administration. In the sub-chronic toxicity study, E. platyloba was administered for 45 days. Mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histological markers were monitored during the study.
We found no mortality and no abnormality in clinical signs, body weight, or necropsy findings in any of the animals in the acute study. The results of the subchronic study showed no significant difference in hematological parameters in either sex. There was a significant increase in lactate dehydrogenase in the female groups. A significant increase in the relative lung weight of female rats was noted at 500 mg/kg. Histopathological examinations revealed intra-alveolar hemorrhage in the male rats (500 mg/kg). In the females, congestion of the alveolar capillaries (at 500 mg/kg) and liver bridging necrosis (at 200 mg/kg) were significantly increased.
The no observed adverse effect level of E. platyloba was determined to be 200 and 50 mg/kg for male and female rats, respectively.
Echinophora Platyloba; Rat; Acute Toxicity; Subchronic Toxicity
A combined dominant lethal-fertility study was conducted in which male and female Sprague-Dawley (CD) rats were exposed to 0, 30, 100 or 300 ppm of ethylene glycol monomethyl ether (EGME) vapor for 6 hr/day, 5 days/week for 13 weeks and then mated to untreated counterparts. Among males, fertility was completely suppressed after exposure to 300 ppm. A partial restoration of reproductive function was evident following 13 weeks of recovery. No treatment-related reproductive effects were observed among males exposed subchronically to 100 ppm, or among females exposed to 300 ppm or below of EGME. Studies to assess the effects of inhaled EGME on embryonal and fetal development were also conducted in Fischer 344 rats, CF-1 mice, and New Zealand White rabbits. Rats and rabbits were exposed to concentrations of 0, 3, 10 or 50 ppm for 6 hr/day on days 6-15 or 6-18 of gestation, respectively. Exposure of rabbits to 50 ppm resulted in significant teratologic effects, an increased resorption rate, and decreased fetal body weight. Slight fetotoxicity in the form of skeletal variations were observed among rats exposed to 50 ppm. Exposure of pregnant mice to 0, 10, or 50 ppm for 6 hr/day on days 6-15 of gestation resulted in slight fetotoxicity at 50 ppm. No significant treatment-related effects were observed at 10 ppm of EGME or below in any of the species tested. Separate groups of pregnant rats and rabbits were exposed to 0, 500, 1500 or 3000 ppm of propylene glycol monomethyl ether (PGME) during organogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)
It has been demonstrated that some strains of Bacillus coagulans can survive extremes of heat, acidity of the stomach, and bile acids, to which commonly consumed probiotics are susceptible. A toxicological safety assessment was performed on a proprietary preparation of B. coagulans – GanedenBC30™ – a novel probiotic. Seven toxicologic studies were conducted and included: in vitro bacterial reverse mutation assay; in vitro chromosomal aberration assay; micronucleus assay in mice; acute and 90 day subchronic repeated oral toxicity studies were conducted in Wistar Crl:(WI) BR rats; acute eye and skin irritation studies were conducted in rabbits.
The results of this toxicological safety assessment indicate that GanedenBC30™B. coagulans does not demonstrate mutagenic, clastogenic, or genotoxic effects. Furthermore, the results of the acute and 90-day subchronic oral toxicity studies in rats resulted in the conclusion of a NOAEL greater than 1000 mg/kg per day. Since the concentration of the cell mass used in the 90-day study was 1.36 × 1011 CFUs/g, this corresponds to 95.2 × 1011 CFUs for a 70 kg human and since the suggested human dose is in the range of 100 × 106 to 3 × 109 CFUs, this gives a safety factor ranging from 3173 to 95,200 times. Based upon scientific procedures and supported by history of use, GanedenBC30™ is considered safe for chronic human consumption.
A/G, albumin to globulin ratio; Alb, albumin; ALKP, alkaline phosphatase; ALT, alanine transaminase; ANOVA, analysis of variance; APTT, activated partial thromboplastin time; AST, aspartate transaminase; ATCC, American Type Tissue Collection; BC30 or GBI-30-SF, GanedenBC30™; Bw, body weight; CFU, colony forming unit; Creat, creatinine; DMSO, dimethyl sulfoxide; EEC, European Economic Community; EC, European Community; ELISA, enzyme-linked immunosorbent assay; EU, European Union; FBS, fetal bovine serum; GGT, gamma-glutamyltransferase; GRAS, generally recognized as safe; Hct, hematocrit; Hgb, hemoglobin; MC, methyl cellulose; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration; MCV, mean corpuscular volume; MPV, mean platelet volume; NOAEL, no observed adverse effect level; OECD, Organization for Economic Cooperation and Development; Plt, platelet; PT, prothrombin time; RBC, red blood cell; RDW, red blood cell distribution width; Retic, reticulocyte; S.D., standard deviation; T Bili, total bilirubin; T chol, total cholesterol; T Prot, total protein; UV, ultraviolet; v/v, volume per volume; WBC, white blood cell; Bacillus coagulans; BC30; Functional foods; GRAS; Gut flora; Probiotics
Corrigiola telephiifolia Pourr. (Caryophyllaceae) is a Moroccan medicinal plant. Despite its popular usage, no study has been published concerning its toxicological profile. The acute toxicity of C. telephiifolia root extract was evaluated by giving it orally to mice at single doses of 5000, 10000, and 14000 mg/kg bodyweight. The extract was also administered at doses of 5, 70, and 2000 mg/kg bodyweight per day to rats for a forty-day toxicity study. No mortality or signs of toxicity were observed in the acute study. In the forty-day study in rats, the extract at 5 mg/kg/day showed no toxicological effects in either sex. At 70 mg/kg/day, the treated group differed from the control only by a significant decrease in serum concentrations of sodium and chloride ions (P < .05). At the dose of 2000 mg/kg/day, the extract significantly increased the serum concentrations of creatinine, alkaline phosphatase, gamma-glutamyltransferase and phosphorus (P < .05) all suggestive of functional nephrotoxicity and hepatotoxicity. The relative bodyweight of both sexes decreased at the dose of 2000 mg/kg/day, with a fast recovery for males. Histological examination did not reveal any treatment-related effects. In conclusion, Corrigiola extract appears safe at the doses used ethno-medicinally. Much higher doses pose toxicological risks.
The present study investigates the use of novel anionic lipoplexes composed of physiological components for plasmid DNA delivery into mammalian cells in vitro. Liposomes were prepared from mixtures of endogenously occurring anionic and zwitterionic lipids, 1,2-dioleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) (DOPG) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), respectively, at a molar ratio of 17∶83 (DOPG:DOPE). Anionic lipoplexes were formed by complexation between anionic liposomes and plasmid DNA molecules encoding green fluorescence protein (GFP) using Ca2+ ions. Transfection and toxicity were evaluated in CHO-K1 cells using flow cytometry and propidium iodide staining, respectively. Controls included Ca2+-DNA complexes (without lipids), anionic liposomes (no Ca2+), and a cationic liposomal formulation. Efficient delivery of plasmid DNA and subsequent GFP expression was achieved using anionic lipoplexes. Transfection efficiency increased with Ca2+ concentration up to 14 mM Ca2+, where transfection efficiency was 7-fold higher than in untreated cells, with minimum toxicity. Further increase in Ca2+ decreased transfection. Transfection efficiency of anionic lipoplexes was similar to that of cationic liposomes (lipofect Amine), whereas their toxicity was significantly lower. Ca2+-DNA complexes exhibited minimal and irregular transfection with relatively high cytotoxicity. A model was developed to explain the basis of anionic lipoplex uptake and transfection efficacy. Effective transfection is explained on the formation of nonbilayer hexagonal lipid phases. Efficient and relatively safe DNA transfection using anionic lipoplexes makes them an appealing alternative to be explored for gene delivery.
anionic liposomes; gene delivery; transfection; nonviral vector; lipoplex; flow cytometry
The efficient delivery of plasmids encoding antigenic determinants into dendritic cells (DCs) that control immune response is a promising strategy for rapid development of new vaccines. In this study, we prepared a series of targeted cationic lipoplex based on two synthetic lipid components, mannose-poly(ethylene glycol, MW3000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (Mannose-PEG3000-DSPE) and O-(2R-1,2-di-O-(1'Z,9'Z-octadecadienyl)-glycerol)-3-N-(bis-2-aminoethyl)-carbamate (BCAT), that were formulated with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) for evaluation as non-viral vectors for transgene expression in DCs. First, we optimized the N:P ratio for maximum transfection and then screened the effects of mannose targeting for further enhancement of transfection levels. Our results indicate that efficient delivery of gWIZ GFP plasmid into DCs was observed for mannose compositions of ~10%, whereas low transfection efficiencies were observed with non-targeted formulations. Mannose-targeted lipofectamine complexes also showed high GFP expression levels in DCs relative to non-targeted lipofectamine controls. The best transfection performance was observed using 10 mol % Mannose-PEG3000-DSPE, 60 mol% BCAT, and 30 mol % DOPE, indicating that the most efficient delivery into DCs occurs via synergistic interaction between mannose targeting and acid-labile, fusogenic BCAT:DOPE formulations. Our data suggest that mannose-PEG3000-DSPE:BCAT:DOPE formulations may be effective gene delivery vehicles for the development of DC-based vaccines.
Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4 000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3 488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification.
Litsea elliptica; Acute toxicity; Subacute toxicity; Median lethal dose (LD50); Natural insecticide; Non-observed-adversed-effect level (NOAEL)
The antimicrobial activity of silver nanoparticles has resulted in their widespread use in many consumer products. Yet, despite their many advantages, it is also important to determine whether silver nanoparticles may represent a hazard to the environment and human health.
Thus, to evaluate the genotoxic potential of silver nanoparticles, in vivo genotoxicity testing (OECD 474, in vivo micronuclei test) was conducted after exposing male and female Sprague-Dawley rats to silver nanoparticles by inhalation for 90 days according to OECD test guideline 413 (Subchronic Inhalation Toxicity: 90 Day Study) with a good laboratory practice system. The rats were exposed to silver nanoparticles (18 nm diameter) at concentrations of 0.7 × 106 particles/cm3 (low dose), 1.4 × 106 particles/cm3 (middle dose), and 2.9 × 106 particles/cm3 (high dose) for 6 hr/day in an inhalation chamber for 90 days. The rats were killed 24 hr after the last administration, then the femurs were removed and the bone marrow collected and evaluated for micronucleus induction.
There were no statistically significant differences in the micronucleated polychromatic erythrocytes or in the ratio of polychromatic erythrocytes among the total erythrocytes after silver nanoparticle exposure when compared with the control.
The present results suggest that exposure to silver nanoparticles by inhalation for 90 days does not induce genetic toxicity in male and female rat bone marrow in vivo.
Silver nanoparticles; Genotoxicity; OECD test guidelines; In vivo micronuclei test; Good laboratory practice; Inhalation toxicity
The Zymbal gland, a sebaceous tissue associated with the ear duct of certain rodent species, is a principal target for carcinogenesis by benzene. To investigate the mechanism of induction of tumors in the rat Zymbal gland, we have developed a procedure for primary culture of epithelial cells from Zymbal gland explants so that cytogenetic analysis can be performed on this target tissue following an in vivo exposure to benzene. Cytogenetic analysis performed 45 hr after in vivo oral dosing with benzene revealed chromosome damage that occurred as a result of acute, subchronic, and chronic dosing. This damage, expressed as a dose-related increase in the frequency of micronucleated cells, was observed in Sprague-Dawley female rats over a range of benzene doses from 12.5 to 250 mg/kg/day, and in male Fischer 344 rats at doses ranging from 1 to 200 mg/kg/day. These results are consistent with the known clastogenicity of benzene in mouse bone marrow, which is also a target tissue. This study is the first report of a genotoxic effect of benzene in the rat Zymbal gland and shows that micronucleus formation may be used as a correlate for carcinogenesis induced by benzene in this target tissue.
This study evaluated the subchronic toxicity of selected halomethanes which are drinking water contaminants. The compounds studied were trichloromethane, bromodichloromethane, dibromochloromethane and tribromomethane. Subchronic 14-day gavage studies were performed with the use of doses encompassing one-tenth the LD50 for the compounds. A 90-day gavage study of one of the compounds, trichloromethane, was also done. Parameters observed included body and organ weights, histopathology, hematology, clinical chemistries, and hepatic microsomal enzyme activities. Toxicity to the humoral immune system was assessed by measuring the number of splenic IgM antibody-forming cells and the serum antibody level to sheep erythrocytes. Cell-mediated immunity was evaluated by measuring the delayed type hypersensitivity response and popliteal lymph node proliferation response to sheep red blood cells. The functional activity of the reticuloendothelial system, as measured by the vascular clearance rate and tissue uptake of 51Cr sheep red blood cells was also determined. The major effects of the halomethanes were increased liver weights, elevations of SGPT and SGOT, decreased spleen weights and a decrease in the number of splenic IgM antibody-forming cells. The humoral immune system appeared to be an indicator of halomethane toxicity. There is evidence that subchronic 14-day exposure may be of greater value than long-term studies in determining the toxicity of these compounds.
Acute oral consumption of various natural inhibitors of amylase (bean and hibiscus extracts) and sucrase (L-arabinose) reduce absorption of starch and sucrose respectively in rats and pigs measured by lessened appearance of circulating glucose levels. The present subchronic study was designed to determine whether these selected inhibitors of gastrointestinal starch and sucrose absorption (so-called “carb blockers”) remain effective with continued use and to assess their metabolic influences after prolonged intake. Sprague-Dawley rats were gavaged twice daily over nine weeks with either water or an equal volume of water containing a formula that included bean and hibiscus extracts and L-arabinose. To estimate CHO absorption, control and treated Sprague-Dawley rats were gavaged with either water alone or an equal volume of water containing glucose, rice starch, sucrose, or combined rice starch and sucrose. Circulating glucose was measured at timed intervals over four hours. The ability to decrease starch and sucrose absorption use. No toxic effects (hepatic, renal, hematologic) were evident. Blood chemistries revealed significantly lower circulating glucose levels and a trend toward decreased HbA1C in the nondiabetic rats receiving the natural formulation compared to control. Subchronic administration of enzyme inhibitors was also associated with many metabolic changes including lowered systolic blood pressure and altered fluid-electrolyte balance. We postulate that proper intake of natural amylase and sucrase inhibitors may be useful in the prevention and treatment of many chronic disorders associated with perturbations in glucose-insulin homeostasis secondary to the rapid absorption of refined CHO.
starch blockers; bean and hibiscus extracts; sucrose blockers; L-arabinose; hibiscus extract