Acute and sub-chronic toxicity studies of the extract of Thunberg Fritillary Bulb

The aim of this study was to investigate the acute and sub-chronic toxicity of extract of Thunberg Fritillary Bulb. For the acute toxicity tests, graded doses of the extract were administered orally to mice. The animals were observed for toxic symptoms and mortality daily for 14 days. In the sub-chronic toxicity study, rats were orally administered the extract at doses of 1 and 3 mg/kg body weight (BW) for 26 weeks. After 26 weeks, the rats were sacrificed for hematological, biochemical and histological examination. In the acute toxicity tests, the estimated median lethal dosage (LD₅₀) was 52.2 mg/kg body weight in the mice. In the sub-chronic toxicity tests, a dose of 1 mg/kg body weight presented no toxicity. Above the 1 mg/kg dose, the main adverse signs observed in male rats were body or head tremor and spontaneous motor activity reduction. There were no other significant changes observed in hematology, blood biochemistry, organ weight and organ histology. The overall findings of this study indicate that the extract of Thunberg Fritillary Bulb is non-toxic up to 1 mg/kg body weight, which can be considered a safe application dose.     

Acute and 13 weeks subchronic toxicological evaluation of naringin in Sprague-Dawley rats

Naringin is widely distributed in plant foods and has not previously been evaluated for safety through standard in vivo toxicological studies. In the present study, acute and subchronic oral toxicity studies of naringin were designed and conducted in Sprague-Dawley (SD) rats. Acute oral administration of naringin was done as a single bolus dose up to 16 g/kg and subchronic toxicity study for 13 weeks was done by oral administration at doses of 0 (control), 50, 250 and 1250 mg/kg in SD rats. There were no mortality, adverse clinical signs, abnormal changes in body weights or food consumption, toxicologically relevant changes in hematology, clinical biochemistry and macroscopic findings during 14 days of the acute toxicity study. During the subchronic oral toxicity study, no mortality and toxicologically significant changes in clinical signs, food consumption, opthalmoscopic examination, hematology, clinical biochemistry, serum sex hormone, macroscopic findings, organ weights and histopathological examination except for slight body weight decrease were noted and attributed to naringin administration. These observations suggest that naringin is practically non-toxic for SD rats in oral acute toxicity study and the no-observed-adverse-effect-level (NOAEL) of naringin in rats is greater than 1250 mg/kg/day when administered orally for 13 consecutive weeks.     

Toxicological assessment of combined lead and cadmium: Acute and sub-chronic toxicity study in rats

The exposure to chemical mixtures is a common and important determinant of toxicity and receives concern for their introduction by inhalation and ingestion. However, few in vivo mixture studies have been conducted to understand the health effects of chemical mixtures compared with single chemicals. In this study, the acute and 90 day sub-chronic toxicity tests of combined Pb and Cd were conducted. In the acute toxicity test, the LD₅₀ value of Pb(NO₃)₂ and CdCl₂ mixture by the oral route was 2696.54 mg/kg by Bliss method. The sub-chronic treatment revealed that the low-dose combination of Pb and Cd exposures can significantly change the physiological and biochemical parameters of the blood of Sprague–Dawley (SD) rats with dose–response relationship and causes microcytic hypochromic anemia and the damages of liver and kidney of the SD rats to various degrees. Histopathological exams showed that the target organs of Pb and Cd were testicle, liver, and kidneys. These observations suggest that Pb and Cd are practically additive-toxic for the SD rats in oral acute toxicity studies. The lowest observed adverse-effect level in rats may be lower than a dose of 29.96 mg/(kg bw day) when administered orally for 90 consecutive days.     

Developmental toxicity study of CBLB502 in Wistar rats

CBLB502 is a derivative of a microbial protein that binds to Toll-like receptor 5. It is demonstrated to reduce inflammatory response from acute stresses, such as radiation in animal models. We determined the potential developmental toxicity of CBLB502 in rats. Four groups of 25 time-mated female Wistar rats/group received subcutaneously 0, 30, 100, or 300 μg/kg/day of CBLB502 from Gestation Days (GD) 6 to 17 at a dose volume of 1.0 mL/kg. Toxicokinetic evaluation was performed on GD 6 and 17. On GD 20 C-section was performed for uterine evaluation and blood samples collected from each dam for immunogenicity assay.Significant decrease in gestation body weight, weight changes and food consumption indicative of maternal toxicity were observed in all dose groups. Also adjusted body weight and weight changes were seen at 300 μg/kg/day. No external, visceral and skeletal abnormalities were observed. The NOAEL for developmental toxicity was estimated to be ≥300 μg/kg/day.     

Scientific evaluation of the acute toxicity and 13-week subchronic toxicity of Rheum emodi rhizome extracts in Sprague Dawley rats

Rheum emodi has been used as an edible and medicinal plant in Tibet and Kashmir for a long period of time, while safety evaluation of this plant has not yet been investigated. In this study, acute and subchronic oral toxicity studies of aqueous extract of R. emodi (AERE) rhizome were conducted in SD rats. Animals were treated with a single dose of 1000, 2000, 4000 or 10,000 mg/kg of AERE in the acute toxicity. In subchronic oral toxicity, animals were randomly divided into four groups (10 rats/sex/group) and received doses of 0, 1000, 2000, and 4000 mg/kg/d of AERE for 90 days. Daily clinical observations, weekly measurement of body weight and food consumption were conducted. Blood and urine were collected on days 91 to measure changes. At necropsy, selected organs were weighed and recorded, and histological examination was performed. During the subchronic oral toxicity study, no mortality, obvious treatment-related clinical signs and urinalysis parameters were observed. Differences in weight gain, food consumption, hematology, biochemistry, relative organ weight and histopathology examinations between the treated group and the control group were not considered treatment-related. Our results indicated that the no-observed-adverse-effect level (NOAEL) for AERE was 4000 mg/kg/d in both genders.     

Developmental toxicity assessment of the new turf herbicide,methiozolin ([5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3,3(3-methylthiophen-2-yl)-1,2-isoxazoline]), in rabbits

Methiozolin is a new herbicide to control annual bluegrass (Poa annua L.) and large crabgrass (Digitaria sanguinalis (L.) Scop.) in various turfgrasses. The potential of methiozolin to induce maternal and developmental toxicity was investigated in the pregnant New Zealand White Rabbits. Methiozolin was, at dose levels of 0, 125, 250 and 500 mg/kg/day, administered by oral gavage to artificially inseminated rabbits (25 females per group) from days 6 to 28 of gestation. All does were subjected to Cesarean section on day 29 of gestation. At 500 mg/kg/day, treatment-related toxicities including abortion (10/22), decreased mean body weight, weight gain, net body weight change, reduced food consumption and decreased fetal weight were observed. At 125 and 250 mg/kg/day, no signs of maternal and developmental toxicity were observed. There were no treatment-related external, visceral and skeletal abnormalities of fetuses at all doses tested. In the current experimental conditions, the no observed adverse effect levels (NOAELs) of methiozolin are considered to be 250 mg/kg/day for does and prenatal development.     

Cytotoxicity,acute and subchronic toxicity of ionic liquid,didecyldimethylammonium saccharinate,in rats

The aim of this study was to investigate cytotoxicity, acute and subchronic oral toxicity of an ionic liquid didecyldimethylammonium saccharinate [DDA][Sac] in rat.IC₅₀ values tested on six human cell lines varied from 1.44 μM to 5.47 μM. The compound tested was classified to the 4th toxicity class with a fixed LD₅₀ cut-off value 500 mg/kg. Organ pathology induced by [DDA][Sac] in an acute experiment included exfoliation of the surface layer of the colon and alveolar septa in lung parenchyma. In a subchronic experiment rats were administered 10, 30 and 100 mg/kg/day [DDA][Sac] for 28 days. Reduced body weight gain and slightly reduced food consumption was observed particularly in high-dose rats. Slight hematology changes were found only in mid-dose females. Statistically significant changes in clinical chemistry parameters included: increases in the ALT, SDH, ALP and GGT activities, and in glucose, blood urea nitrogen and creatinine concentrations. However, these changes did not occur in both sexes and were not dose-related with the exception of ALP in females. No treatment-related microscopic changes were observed in a subchronic experiment. Under the condition of this study the lowest-observed-adverse-effect level of [DDA][Sac] was considered to be 10 mg/kg/day.     

Safety evaluation of a natural eggshell membrane-derived product

Natural Eggshell Membrane (NEM®) is a novel dietary ingredient that contains naturally occurring glycosaminoglycans and proteins essential for maintaining healthy joint and connective tissues. NEM® was evaluated for safety via in vitro and in vivo toxicological studies. This included testing for cytotoxicity, genotoxicity, acute oral toxicity, and 90-day repeated-dose oral toxicity. NEM® did not exhibit any cytotoxic effects at a dose of 100 μg in an in vitro human cell viability assay after incubation for up to 20 h. NEM® did not exhibit any genotoxic effects in an in vitro assay of four strains of histidine-dependent Salmonella typhimurium and one strain of tryptophan-dependent Escherichia coli at a dose of up to 5000 μg/plate. NEM® did not exhibit any signs of acute toxicity in rats at a single oral dose of up to 2000 mg/kg body weight, nor signs of toxicity (via urinalysis, hematology, clinical chemistry, or histopathological evaluation) in rats at a repeated oral dose of up to 2000 mg/kg body weight per day for 90 days. The results of these studies suggest that NEM® may be safe for human consumption.     

Embryo-fetal development toxicity of honokiol microemulsion intravenously administered to pregnant rats

The aim of this study was to evaluate the embryo-fetal development toxicity of honokiol microemulsion. The drug was intravenously injected to pregnant SD rats at dose levels of 0, 200, 600 and 2000 μg/kg/day from day 6–15 of gestation. All the pregnant animals were observed for body weights and any abnormal changes and subjected to caesarean-section on gestation day (GD) 20; all fetuses obtained from caesarean-section were assessed by external inspection, visceral and skeletal examinations. No treatment-related external alterations as well as visceral and skeletal malformations were observed in honokiol microemulsion groups. There was no significant difference in the body weight gain of the pregnant rats, average number of corpora lutea, and the gravid uterus weight in the honokiol microemulsion groups compared with the vehicle control group. However, at a dose level of 2000 μg/kg/day, there was embryo-fetal developmental toxicity observed, including a decrease in the body length and tail length of fetuses. In conclusion, the no-observed–adverse-effect level (NOAEL) of honokiol microemulsion is 600 μg/kg/day, 75 times above the therapeutic dosage and it has embryo-fetal toxicity at a dose level of 2000 μg/kg/day, which is approximately 250 times above the therapeutic dosage.     

Cadmium induced pathophysiology: Prophylactic role of edible jute (Corchorus olitorius) leaves with special emphasis on oxidative stress and mitochondrial involvement

The present study was undertaken to evaluate the protective effect of aqueous extract of Corchorus olitorius leaves (AECO) against CdCl₂ intoxication. In vitro bioassay on isolated mice hepatocytes confirmed dose dependent cytoprotective effect of AECO. The CdCl₂ (30 μM) exhibited a significantly increased levels of lipid peroxidation, protein carbonylation along with the reduction of antioxidant enzymes and reduced glutathione levels in hepatocytes. AECO (200 and 400 μg/ml) + CdCl₂ (30 μM) could significantly restore the aforementioned oxidation parameters in hepatocytes. Beside this, AECO could significantly reduce Cd-induced increase in Bad/Bcl-2 ratio and the over-expression of NF-κB, caspase 3 and caspase 9. In in vivo assay, CdCl₂ (4 mg/kg body weight, for 6 days) treated rats exhibited a significantly increased intracellular Cd accumulation, oxidative stress and DNA fragmentation in the organs. In addition, the haematological parameters were significantly altered in the CdCl₂ treated rats. Simultaneous administration of AECO (50 and 100 mg/kg body weight), could significantly restore the biochemical, antioxidant and haematological parameters near to the normal status. Histological studies of the organs supported the protective role of jute leaves. Presence of substantial quantity of phenolic compounds and flavonoids in extract may be responsible for overall protective effect.     

Characterisation and toxicological assessment of Neutral Methacrylate Copolymer for GRAS evaluation

Neutral Methacrylate Copolymer is a fully polymerised copolymer used in the pharmaceutical industry to permit pH-independent delayed release of active ingredients from oral dosage forms. This function has potential use with food supplements and this article describes available information on the safety of the substance.Oral administration of radiolabelled copolymer to rats resulted in the detection of chemically unchanged copolymer in the faeces, with negligible absorption. Safety studies revealed no adverse toxicity following repeated administration at doses of up to 2000 mg/kg bw/d in a sub-chronic study in rats or 250 mg/kg bw/d in a sub-chronic study in dogs. No reproductive toxicity occurred at up to 2000 mg/kg bw/d in rats or rabbits. The substance shows no evidence of genotoxicity, has low acute toxicity and no irritation or sensitisation potential.An ADI value of 20 mg/kg bw was concluded from two alternative approaches. Daily exposure from use in dietary supplements is estimated as up to 10.0 mg/kg bw in adults and 13.3 mg/kg bw in children. There would therefore appear to be no safety concerns under the intended conditions of use. The information provided is intended to support an evaluation that the substance may be “generally recognized as safe” (GRAS).     

Preliminary assessment of potential toxicity of methylated soybean protein and methylated β-lactoglobulin in male Wistar rats

Methylated soybean protein (MSP) and methylated β-lactoglobulin (MLG), previously confirmed for their antibacterial and antiviral activities, were tested for their potential toxicity in Wistar male Albino rats as one single dose (2500, 5000 and 10,000 mg/kg body wt) or as repeated daily dose (500 and 2500 mg/kg body wt/day) over 28 days to assess potential toxicity. Single acute administration of very high doses (2500, 5000 and 10,000 mg/kg body wt) of MSP and MLG did not produce any mortality. Changes in body weight, organ weight, hematological parameters, histo-pathological images of selected organs, serum albumin, globulin and albumin/globulin ratio, cholesterol, triglycerides and electrolytes were all within normal amounts in the rats fed with these two methylated proteins and not significantly different from controls. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatinine and urea were slightly reduced by the administration of these two modified proteins indicating the absence of any adverse effect on hepatic or renal functions.     

Toxicological evaluation of peroxy sulfonated oleic acid (PSOA) in subacute and developmental toxicity studies

Peroxy sulfonated oleic acid (PSOA) is a new coupler used in sanitizing solutions primarily for the food and beverage industry. The toxicity of PSOA was evaluated in a 28-day repeat dose study according to OECD 407 guidelines with a 14-day recovery period and a developmental toxicity study according to OECD 414 guidelines. In both studies, PSOA was administered once daily via gavage at 0, 5, 15 and 50 mg/kg/day to Sprague–Dawley rats. Due to its corrosive properties, the highest test concentration was restricted to 0.5%. No findings related to PSOA administration were observed for the 28-day repeat-dose study and the NOEL is 50 mg/kg/day. Additionally, no impairment of the mucous membranes of the gastrointestinal tract was observed up to 0.5%, which is considered the NOEC in terms of local toxicity. For the developmental study, an embryo-fetal NOEL of 50 mg/kg/day was identified and the maternal NOEL is considered to be 15 mg/kg/day, based on slight reductions in maternal body weight and food consumption, as well as a modest increase in the incidence of clinical observations at the high dose. These findings demonstrate that PSOA appears to have minimal potential to induce toxicity associated with repeat-dose or developmental exposures.     

Acute and subchronic toxicological evaluation of Mequindox in Wistar rats

We studied an acute and subchronic oral toxicity of Mequindox (MEQ), a quinoxaline 1,4-dioxide antimicrobial promoter, in Wistar rats according to OECD guidelines. For acute toxicity study, single doses of MEQ at 175, 550 and 2000 mg/kg b.w. were administered to rats by oral gavage. The calculated LD₅₀ was 550 mg/kg b.w. In subchronic study, rats were fed diets containing 0, 55, 110 or 275 mg MEQ/kg. There was a reduction in body weight of rats fed 275 mg MEQ/kg diet. At 90 days autopsy, a significant decrease in the kidney weight was observed in males while an increase in relative liver and adrenal weights were observed in females fed 275 mg MEQ/kg diet. There was a significant increased in alanineaminotransferase (ALT) and malondialdehyde (MDA) concentrations in males, superoxide dismutase (SOD) activities in females, and aspartateaminotransferase (AST) levels in serum of both genders fed 275 mg MEQ/kg diet. Other toxic effects of 275 mg MEQ/kg diet included significant decrease in sodium and significant increase in potassium concentrations in serum in both genders. We may conclude that MEQ can induce hepatic and adrenal histological changes as well as leaking of different serum constituents in Wistar rats.     

A 90-day subchronic oral toxicity study of triterpene-enriched extract from Alismatis Rhizoma in rats

Alismatis Rhizoma has been used in East Asia as a traditional treatment for various illnesses and symptoms, and the presence of protostane-type triterpenes has been claimed to provide health benefits. To investigate the subchronic toxicity of triterpene-enriched extract from Alismatis Rhizoma (TEAR), a 90-day oral toxicity study was conducted in rats. Sprague–Dawley rats were randomly divided into four groups (10 rats/sex/group) and received doses of 0, 360, 720, and 1440 mg/kg/d of TEAR for 90 days. Daily clinical observations as well as weekly measurement of body weight and food consumption were conducted. Blood samples were obtained on day 91 to measure changes in hematology and biochemistry. Urine samples were collected on days 0 and 91 for urinalysis. At necropsy, selected organs were weighed and recorded, and histological examination was performed. No mortality or obvious treatment-related clinical signs, hematology, urinalysis parameters, and macroscopic or microscopic examinations were observed. Differences in weight gain, food consumption, biochemistry, and relative organ weight between the treated group and the control group were not considered treatment-related. On the basis of these findings, the no-observed-adverse-effect level for TEAR was 1440 mg/kg/d in both sexes.     

Acute and subchronic toxicity as well as mutagenic evaluation of essential oil from turmeric (Curcuma longa L)

The present study investigated the acute, subchronic and genotoxicity of turmeric essential oil (TEO) from Curcuma longa L. Acute administration of TEO was done as single dose up to 5 g of TEO per kg body weight and subchronic toxicity study for thirteen weeks was done by daily oral administration of TEO at doses 0.1, 0.25 and 0.5 g/kg b.wt. in Wistar rats. There were no mortality, adverse clinical signs or changes in body weight; water and food consumption during acute as well as subchronic toxicity studies. Indicators of hepatic function such as aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) were unchanged in treated animals compared to untreated animals. Oral administration of TEO for 13 weeks did not alter total cholesterol, triglycerides, markers of renal function, serum electrolyte parameters and histopathology of tissues. TEO did not produce any mutagenicity to Salmonella typhimurium TA-98, TA-100, TA-102 and TA-1535 with or without metabolic activation. Administration of TEO to rats (1 g/kg b.wt.) for 14 days did not produce any chromosome aberration or micronuclei in rat bone marrow cells and did not produce any DNA damage as seen by comet assay confirming the non toxicity of TEO.     

Toxicological evaluation of neem (Azadirachta indica) oil: Acute and subacute toxicity

Neem (Azadirachta indica), popularly known as traditional medicine is a native plant in India. Neem oil is a vegetable oil derived from seeds or fruits of the neem tree through pressing or solvent extraction, and largely used in popular medicine to have antifungal, antibacterial, antimalarial, antiparasitic, anti-inflammatory, as well as immunemodulatory properties in different animal species. In the present study, acute and 28-day subacute toxicity tests were carried out. In the acute toxicity test, the LD₅₀ values of neem oil were found to be 31.95 g/kg. The subacute treatment with neem oil failed to change body weight gain, food and water consumption. Serum biochemistry analysis showed no significant differences in any of the parameters examined under the dose of 1600 mg/kg/day. Histopathological exams showed that the target organs of neem oil were testicle, liver and kidneys up to the dose of 1600 mg/kg/day.     

Ninety day repeated gavage administration of Hipphophae rhamnoides extract in rats

Hippophae rhamnoides, is a high altitude plant, possesses immunomodulatory, anti-oxidant, anti-bacterial and adaptogenic activity and is widely used in treatment of various diseases. The present study was designed to ascertain the safety of aqueous extract of H. rhamnoides fruit when administered by gavage to rats for 90 days. Four groups of animals, each consisting of 15 males and 15 females, were adminstered 0, 100, 250, or 500 mg/kg extract, in a single dose/day. There were no treatment related change in mean body weight, organ/body weight ratio, histological, hematological and biochemical parameters studied in rats of either sex administered with extract at any dose evaluated. However, a significant increase in plasma glucose levels was observed in animals supplemented with 250 or 500 mg/kg extract, which returned to normal after a 2-week withdrawal of treatment. These results indicate no adverse effects of extract at a dose of 100 mg/kg body weight/day in rats administered for 90-days. Based on the findings of this study, the NOAEL was 100 mg/kg body weight/day of aqueous fruit extract of seabuckthorn in rats.     

Subchronic,reproductive, and maternal toxicity studies with tertiary butyl acetate (TBAC)

Tertiary-butyl acetate (TBAC) was tested for subchronic toxicity in rats and mice and reproductive toxicity in rats at inhalation concentrations of 0, 100, 400 or 1600 ppm. An oral maternal toxicity study was conducted in rats at dose levels of 0, 400, 800, 1000 and 1600 mg kg⁻¹ d⁻¹. In the inhalation studies, hematology, clinical chemistry, urinalysis, gross pathology and the majority of body weight and feed consumption values were unaffected. Exposure to TBAC at concentrations of 400 ppm and higher caused transient hyperactivity in mice and some evidence of increased motor activity counts in male rats at the 1600 ppm exposure level. TBAC caused α₂u-globulin accumulation in male rat kidneys from all exposure groups and increased liver weights in 1600 ppm rats and mice. Levels of thyroxin were decreased in male mice exposed to 1600 ppm TBAC for 4 weeks but otherwise thyroid endpoints were unaffected in rats and mice at either the 4 or 13 weeks time points. There was no evidence or immunotoxicity or reproductive toxicity in rats. Pregnant rats receiving 1000 mg kg⁻¹ d⁻¹ TBAC exhibited severe signs of acute neurotoxicity and decreased feed consumption and body weight gain. Fetal viability and growth were unaffected.     

Evidence for oral agmatine sulfate safety – A 95-day high dosage pilot study with rats

Agmatine, decarboxylated arginine, exerts beneficial effects in various experimental disease models. Clinical trials indicate the safety and effectiveness of short-term (up to 21 days) high dose regimens of oral agmatine sulfate, but longer term studies are lacking. This pilot study undertook to assess the safety of a longer term high dosage oral agmatine sulfate in laboratory rats. Adult Wistar rats consumed 5.3 g/l agmatine sulfate in their drinking water for 95 days, a regimen estimated to result in a daily dosage of absorbed agmatine of about 100 mg/kg. Animals’ body weight, water consumption and blood pressure were periodically measured, and general cage behavior, fur appearance, urination and feces appearance monitored. These parameters were also determined at 20 days after treatment cessation (day 115). On days 95 and 115, animals were euthanized for gross necropsy assessment. Agmatine-treated rats showed slight, but significant reductions in body weight and blood pressure, and reduced water consumption during treatment, which recovered completely within 20 days after treatment cessation. Otherwise, no abnormal behaviors or organ pathologies were observed. These findings are first to suggest apparent safety of sub-chronic high dosage dietary agmatine sulfate in laboratory rats, thus lending further support to the therapeutic applications of agmatine.