Single and repeated dose (28 days) intravenous toxicity assessment of bartogenic acid (an active pentacyclic triterpenoid) isolated from Barringtonia racemosa (L.) fruits in mice

Bartogenic acid (BA), an active pentacyclic triterpenoid, has been reported for anti-diabetic, anti-inflammatory, anti-arthritic, anti-cancer, and anti-tumor activity. However, toxicity profiling of BA has not been reported till date. Hence, this study is designed to evaluate the single dose (12.5, 25, 50 and 100 mg/kg) and repeated dose (1.5, 6, and 24 mg/kg) intravenous toxicity of BA in BALB/c mice. Control group received vehicle. In single dose toxicity study, two mortalities were observed at 100 mg/kg of BA whereas lower doses were well tolerated. In repeated dose toxicity study, no mortality was observed. 1.5 mg/kg of BA was well tolerated in mice of both sexes. At 6 mg/kg of BA, female mice showed significant reduction in the body weight as compared to the control group however no significant change was observed in male mice. 24 mg/kg of BA showed significant reduction in the body weight in mice of both sexes. Further, these mice showed significant change in the relative organ weight. However, no toxicologically relevant changes were observed in hematology, biochemistry, and histopathology. Based on the findings, No-Observed-Adverse-Effect-Level (NOAEL) for BA were found to be<24 mg/kg for male mice and<6 mg/kg for female mice.

Dietary administration of β-ionone epoxide to Sprague-Dawley rats for 90 days

In a 90-day GLP-compliant study groups of Sprague-Dawley rats (10/sex/group) were fed diets containing β-ionone epoxide, a fragrance material and a flavoring substance, at dietary concentrations providing target intakes of 0, 20, 40 and 80 mg/kg bw/day. There were no deaths and no adverse changes in clinical observations, ophthalmological examinations, body weight, body weight gain, food consumption, food efficiency; hematology, serum chemistry, urinalysis parameters; or in macroscopic findings attributable to β-ionone epoxide administration. Increased absolute and relative liver weights in high dose females without correlating hepatic histopathological findings were considered non-adverse. Cortical vacuolation of adrenal zona fasciculata was observed in high-dose males but was considered non-adverse due to the nondegenerative nature of this alteration. β-Ionone epoxide did not influence estrus cyclicity in females and did not affect sperm morphology or epididymal sperm count, homogenization-resistant spermatid count and motility measurements in male rats. The no-observed-adverse-effect level (NOAEL) for administration of β-ionone epoxide in the diet was determined to be the highest dose tested of 80 mg/kg bw/day.

Safety assessment of a novel thermostable phytase

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The toxicity of Phytase TSP a new thermostable phytase was studied.

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No genotoxic or toxic effects were recorded for Phytase TSP.

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The NOAEL for the new Phytase TSP is 1000 mg/kg bw/d.

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The studies support the safety of Phytase TSP as an animal feed additive.

A novel 6-phytase (Phytase TSP, trade name OptiPhos® PLUS) with improved thermostability has been developed for use in animal feed. The safety of the new phytase was evaluated by testing for genotoxicity and subchronic toxicity. In in vitro and in vivo genotoxicity assays Phytase TSP concentrate was not mutagenic and did not induce biologically or statistically significant increases in the frequency of micronucleated polychromatic erythrocytes. In a subchronic toxicity study, male and female rats administered 100, 500 or 1000 mg/kg body weight/day of Phytase TSP concentrate via oral gavage for 90 days had no mortalities, and no treatment-related effects on body weight, food consumption, clinical observations or ophthalmology. Furthermore, there were no changes in haematology, clinical chemistry, urinalysis, gross pathology, organ weights or histopathology that could be attributed to the test article. Several endpoints exhibited statistically significant effects, but none was dose-related or considered to be of toxicological relevance. Based on these results, Phytase TSP concentrate (OptiPhos® PLUS) was not genotoxic and the No Observed Adverse Effect Level (NOAEL) for male and female rats was 1000 mg/kg body weight/day.

Safety evaluation of calcium L-methylfolate

Calcium L-methylfolate (L-5-MTHF-Ca; CAS Number 151533-22-1) is a source of folate and an alternative to folic acid for use in human food and food supplements. The safety of L-5-MTHF-Ca was evaluated by testing for genotoxicity, subchronic and prenatal developmental toxicity. In in vitro assays L-5-MTHF-Ca was not mutagenic and did not induce other chromosomal events. Additionally, L-5-MTHF-Ca was not genotoxic in the in vivo micronucleus test nor did it induce DNA damage in rat liver cells. In a subchronic toxicity study, rats administered up to 400 mg/kg bw/day of L-5-MTHF-Ca via oral gavage for 13 weeks had no treatment-related mortalities, and no treatment-related effects were identified on behaviour, body weight, food consumption, ophthalmology, haematology, or organ weights. No treatment-related macroscopic or histopathological findings were observed. Calcium and sodium levels increased with increasing dosage, however the slight increases were within historical control ranges and reversible after the recovery period. L-5-MTHF-Ca is neither teratogenic nor embryotoxic. Based on the results of the in vitro and in vivo studies, the safe use of L-5-MTHF-Ca as an ingredient in foods is supported. The no observed adverse effect level was the highest dose in the subchronic toxicity study, i.e. 400 mg/kg bw/day for male and female rats.

Evidence of prenatal toxicity of herbal based indigenous formulations for sex selection in rat models

Indigenous preparations(IPs) for a male child is reported from some parts of India. The present study aims to explore the effects of IPs for sex selection or sex selection drugs (SSDs) on pregnancy outcomes in rat models. SSDs contain Bryonia laciniosa, Quercus infectoria and Putranjiva roxburghii along with other ingredients.

Methods

An experimental design with successfully mated female rats were randomized into control and treatment groups. Phase 1 had 2 interventional arms while phase 2 had 3 interventional arms (12 rats/arm) besides control arm. In phase-1, pregnant females were dosed two SSDs(1000 mg/kg) on gestation days 1–5 whereas, in phase-2, on gestation days 6–19 to correlate the effect of the SSDs (500/1000/1500 mg/kg) consumption during different stages of pregnancy. Pregnant females were observed for clinical signs following treatment. The rats were sacrificed one day before expected day of delivery for evaluation. Pregnancy rate, gestation index, number of corpora lutea, and litter size were assessed. Foetuses were examined for sex, skeletal and soft tissue alterations.

Discussion and conclusion

In phase 1, no appreciable findings were there with SSD exposure. In phase 2, intrauterine growth and survival of foetuses were affected when SSDs were administered during organogenesis period. Decreased number of live foetuses and increased incidence of early and late resorption, reduced fetal growth with significant alteration in skeleton and viscera were found in treatment groups in a dose-dependent manner. This correlates well with findings from observational studies in pregnant women. However, such treatment at any dose did not effect sex differentiation.

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Indigenous preparations for sex selection consumed during organogenesis period of pregnancy lead to fetal resorptions.

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Such preparations are likely to cause skeletal and visceral malformations in babies.

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These have no impact on sex ratio.

28-day inhalation toxicity of 3-methoxybutyl chloroformate in rats

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3-MBCF up to 6 ppm induced mortality in 28-day inhalation study of rats.

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The NOAEL of 3-MBCF in 28 day inhalation toxicity study, was less than 3 ppm.

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3-MBCF under 12 ppm did not induce micronucleus formation in the bone marrow of rats.

The 28-day repeated inhalation study was applied for hazard assessment of 3-methoxybutyl chloroformate (3-MBCF) in Sprague Dawley rats. Groups of five rats per sex were exposed 6 h/day, 5 days per week for 4 weeks to test substance concentration (ranging from 3 to 12 ppm) using a whole-body exposure system. At the terminal sacrifice, following blood collection and gross pathological examination, organ weights were determined and fixed organs were examined. The micronucleus test was performed using bone marrow cells. Exposure of 3-MBCF induced mortality at concentrations above 6 ppm. Decreases in body weight and food intake, hematologic alterations, organ weight changes, and gross and microscopic findings were seen even at the lowest concentrations of 3 ppm. Histopathology revealed principal test substance exposure correlated with lesions in the respiratory tract in both male and female rats above 3 ppm. Groups of male rats exposed above 6 ppm show microscopic lesions in spleens, livers, testes and epididymides; however, the micronucleated polychromatic erythrocytes frequency in bone marrow cells was not changed. Based on histopathology of the respiratory tract and other organs, the no observed adverse effect level (NOAEL) of 3-MBCF in the present study was less than 3 ppm.

Magnesium stearate, a widely-used food additive, exhibits a lack of in vitro and in vivo genotoxic potential

Magnesium stearate is widely used in the production of dietary supplement and pharmaceutical tablets, capsules and powders as well as many food products, including a variety of confectionery, spices and baking ingredients. Although considered to have a safe toxicity profile, there is no available information regarding its potential to induce genetic toxicity. To aid safety assessment efforts, magnesium sulfate was evaluated in a battery of tests including a bacterial reverse mutation assay, an in vitro chromosome aberration assay, and an in vivo erythrocyte micronucleus assay. Magnesium stearate did not produce a positive response in any of the five bacterial strains tested, in the absence or presence of metabolic activation. Similarly, exposure to magnesium stearate did not lead to chromosomal aberrations in CHL/IU Chinese hamster lung fibroblasts, with or without metabolic activation, or induce micronuclei in the bone marrow of male CD-1 mice. These studies have been used by the Japanese government and the Joint FAO/WHO Expert Committee on Food Additives in their respective safety assessments of magnesium stearate. These data indicate a lack of genotoxic risk posed by magnesium stearate consumed at current estimated dietary exposures. However, health effects of cumulative exposure to magnesium via multiple sources present in food additives may be of concern and warrant further evaluation.

VaxCelerate II: rapid development of a self-assembling vaccine for Lassa fever

Development of effective vaccines against emerging infectious diseases (EID) can take as much or more than a decade to progress from pathogen isolation/identification to clinical approval. As a result, conventional approaches fail to produce field-ready vaccines before the EID has spread extensively. Lassa is a prototypical emerging infectious disease endemic to West Africa for which no successful vaccine is available. We established the VaxCelerate Consortium to address the need for more rapid vaccine development by creating a platform capable of generating and pre-clinically testing a new vaccine against specific pathogen targets in less than 120 d A self-assembling vaccine is at the core of the approach. It consists of a fusion protein composed of the immunostimulatory Mycobacterium tuberculosis heat shock protein 70 (MtbHSP70) and the biotin binding protein, avidin. Mixing the resulting protein (MAV) with biotinylated pathogen-specific immunogenic peptides yields a self-assembled vaccine (SAV). To meet the time constraint imposed on this project, we used a distributed R&D model involving experts in the fields of protein engineering and production, bioinformatics, peptide synthesis/design and GMP/GLP manufacturing and testing standards. SAV immunogenicity was first tested using H1N1 influenza specific peptides and the entire VaxCelerate process was then tested in a mock live-fire exercise targeting Lassa fever virus. We demonstrated that the Lassa fever vaccine induced significantly increased class II peptide specific interferon-γ CD4(+) T cell responses in HLA-DR3 transgenic mice compared to peptide or MAV alone controls. We thereby demonstrated that our SAV in combination with a distributed development model may facilitate accelerated regulatory review by using an identical design for each vaccine and by applying safety and efficacy assessment tools that are more relevant to human vaccine responses than current animal models.