The subchronic toxicity of higher olefins in Han Wistar rats.

Higher olefins (HO) are a category of unsaturated hydrocarbons widely used in industry applications to make products essential for daily human life. Establishing safe exposure limits requires a solid data matrix that facilitates understanding of their toxicological profile. This in turn allows for data to be read across to other members of the category, which are structurally similar and have predictable physico-chemical properties. Five independent subchronic oral toxicity studies were conducted in Wistar rats with Oct-1-ene, Nonene, branched, Octadec-1-ene, Octadecene and hydrocarbon C12-30, olefin-rich, ethylene polymn. by product, at doses ranging from 20 to 1000 mg/kg bw. These HO were selected considering gut absorption, carbon chain length, double-bond position and carbon backbone structural variations. Generally, limited and non-adverse toxicity effects were observed at the end of the treatment for short carbon chain HO. For instance, alpha 2u-globulin nephropathy in the male rats and liver hypertrophy. No clear trend in systemic toxicity was linked to the double-bond position. Key factors for hazard assessment include absorption, carbon chain length, and branching, with Nonene, branched, identified as the worst-case substance. Taken together, the no observed adverse effect level (NOAEL) of each HO in these subchronic studies was set at the highest dose tested.

90-day oral toxicity study in rats of a protein-rich powder derived from Xanthobacter sp. SoF1.

Xanthobacter sp. SoF1 (SoF1) is an autotrophic hydrogen-oxidizing bacteria that produces protein-rich biomass and has potential to be an alternative protein source that is more environmentally sustainable than animal and plant derived proteins. A protein-rich powder derived from SoF1 was the test material in a 90-day repeated-dose oral toxicity study to explore major toxic effects, demonstrate target organs, and provide an estimate of a no-observed-adverse-effect level (NOAEL). Daily doses of 0 (vehicle only), 375, 750, and 1500 mg/kg bw/day of the test material were administered by gavage to 10 Han:WIST rats/sex/group. An additional group was administered 1290 mg/kg bw/day whey protein concentrate as positive control. No treatment-related adverse effects were observed, and no target organs were determined after 90/91 days of consecutive administration of the test item. A NOAEL of 1500 mg/kg bw/day was determined.

Toxicological Evaluation Verifies the Safety of Oral Administration of Steamed Mature Silkworm Powder in Rats.

Globally, the edible insect industry is emerging due to its potential contributions to food security and environmental sustainability. Edible insects are rapidly being integrated into the development of alternative foods and new pharmaceuticals. Silkworms, known for their high protein content, are not only a potential new source of human food and animal feed but have also been traditionally used for medicinal purposes. However, conventional silkworms are difficult to ingest. To address this, we have developed a steamed and freeze-dried mature silkworm larva powder (SMSP), and it is essential to investigate its potential toxicity and food safety for further studies and applications. Therefore, this study aimed to evaluate the toxicity of SMSP. A toxicity assessment of SMSP was conducted according to OECD guidelines. An oral repeat-administration study was performed on male and female SD rats at doses of 625, 1250, and 2500 mg/kg/day for 4 and 13 weeks. No toxicological changes were observed in clinical signs, body weight, water and food intake, urine tests, hematology, clinical biochemistry, gross findings, or histopathological examination. In conclusion, the no observed adverse effect level (NOAEL) of SMSP was 2500 mg/kg/day, with no target organs identified in either sex of the rats. These results suggest that SMSP is safe, is without side effects and has potential for use as an edible ingredient and in health functional food applications.

Subchronic oral toxic effects of 2,4-dinitroaniline in wistar rats: A comprehensive toxicity evaluation.

2,4-dinitroaniline (2,4-D), a widely used dye intermediate, is one of the typical pollutants, and its potential health risks and toxicity are still largely unknown. To explore its subchronic oral toxicity, Wistar rats (equal numbers of males and females) were used as test animals, and a 90-day oral dosing experiment was conducted, divided into control group, low-dose group (0.055 mg/kg), medium-dose group (0.22 mg/kg), medium-high dose group (0.89 mg/kg), and high-dose group (3.56 mg/kg). The body weight data, clinical appearance, and drug reactions of each test rat within 90 days of dosing were recorded; morning urine samples were collected four times to test for eight urinary indicators; blood samples were collected to test for nineteen hematological indicators and sixteen biochemical indicators; tissue samples were collected for pathological analysis; moreover, the no-observed-adverse-effect level (NOAEL) was determined, and the benchmark dose method was used to support this determination and provide a statistical estimate of the dose corresponding. The results indicated that the chronic toxicity of 2,4-dinitroaniline showed certain gender differences, with the eyes, liver, and kidneys being the main potential target organs of toxicity. Moreover, the subchronic oral NOAEL for 2,4-dinitroaniline was determined to be 0.22 mg/kg body weight (0.22 mg/kg for males and 0.89 mg/kg for females), and a preliminary calculation of the safe exposure limit for human was 0.136 mg/kg. The research results greatly enriched the safety evaluation data of 2,4-dinitroaniline, contributing to a robust scientific foundation for the development of informed safety regulations and public health precautions.

An evaluation of the genotoxicity and 90-day repeated dose oral toxicity in rats of Porphyridium purpureum.

Interest in microalgae products for use in food is increasing, as demands for sustainable and cost-effective food choices grow due to the escalating global population and increase in climate-related struggles with agriculture. Toxicological assessments of some species of microalgae have been conducted, but there were little data available for the oral consumption of the red microalgae Porphyridium purpureum and no data on genotoxicity. This article articulates a genotoxicity assessment and a 90-day repeated dose oral toxicity study in rats performed according to OECD guidelines. Under the experimental conditions applied, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used in the bacterial reverse mutation test. Similarly, the test item did not induce structural chromosomal aberrations in V79 hamster lung cells. The test item also did not cause chromosomal damage in bone marrow of mice in the mammalian micronucleus test. The no observed adverse effect level (NOAEL) of the 90-day repeated dose oral toxicity study in rats was determined to be the highest dose tested, 3000 mg/kg bw/day. These data add to the body of evidence regarding the safety of P. purpureum for human consumption.

A 90-day preclinical toxicological evaluation in rats of a highly purified and concentrated mulberry leaf extract.

Mulberry (genus Morus) leaves have long been used as a human food, especially in Asia, and animal feed. More recently, mulberry leaf extracts have been introduced as a convenient way to consume mulberry for non-nutritional functional effects. Reducose® 5% is an Morus alba leaf extract that has been highly purified and standardized to a content of 5 ± 0.5% 1-deoxynojirimycin, a naturally present polyhydroxylated piperidine alkaloid analog of D-glucose. This extract has previously been evaluated in acute and subacute (28-day) oral toxicity studies in which no adverse effects of the test item were observed in mice or rats, respectively. Due to continued and growing interest in the extract in multinational markets, we have now further investigated potential toxic effects in subchronic (90-day) oral toxicity study in male and female Han:WIST rats. The test item was administered at doses of 850, 1700, and 2550 mg/kg bw/day, and did not cause adverse effects in clinical signs, body weight development, clinical pathology, gross pathology, or histopathology in comparison to the vehicle-control group. The no-observed-adverse-effect-level was determined to be 2550 mg/kg bw/day. These results add to the existing body of both preclinical and clinical work relevant to the safety of the extract and of interest to regulators in various global markets.

Subchronic oral toxicity study of the synbiotic mulberry in male and female Wistar rats.

Mulberry (Morus alba L) fruit is traditionally used in Chinese medicine and has several beneficial effects, such as hypoglycemic, hypolipidemic, and anti-oxidative effects. We previously developed the synbiotic mulberry (SM) containing probiotic Lactobacilli, prebiotic inulin, and mulberry powder. In food supplement development, toxicity is the most important criterion in food and drug regulations before commercialization. Thus, this study aimed to investigate the subchronic toxicity of SM in male and female Wistar rats to evaluate its biosafety. The subchronic toxicity study was conducted by daily oral administration of SM at doses of 250, 500, and 1000 mg/kgBW for 90 days. Male and female rats were evaluated for body weight, organ coefficients, biochemical and hematological parameters, and vital organ histology. The results showed no mortality or toxic changes in the subchronic toxicity study. These results suggested that no observed adverse effect level (NOAEL) of SM in male and female rats has been considered at 1000 mg/kgBW for subchronic toxicity study.

Threshold for increased liver weight is protective of other effects in Peromyscus exposed to PFNA.

Perfluorononanoic acid (PFNA) is a commercially relevant, long-chain (8 fully fluorinated carbon) perfluorinated carboxylic acid. PFNA has limited terrestrial ecotoxicity data and is detected in humans, animals, and the environment. This study is the fourth in a series with the objective of investigating the toxicity of a suite of per- and polyfluoroalkyl substances (PFAS) detected on military installations in a mammal indigenous to North America. Peromyscus leucopus (white-footed mice, ∼25/sex/dose) were exposed via oral gavage to either 0, 0.03, 0.14, 1, or 3 mg PFNA/kg-d for 112 consecutive days (4 wk premating exposure followed by an additional 12 wk of exposure after onset of mating). Parental generation animals were assessed for potential reproductive and developmental effects, organ weight changes, thyroid modulation, and immunotoxicity. Pup weight and survival were assessed at postnatal days 0, 1, 4, 7, and 10. Change in liver weight was determined to yield the most sensitive dose response according to benchmark dose analysis, and serves as the most protective point of departure (BMDL = 0.37 mg/kg-d PFNA). Other effects of PFNA exposure included reduced formation of plaque-forming cells, which are indicative of functional immune deficits (BMDL = 2.31 mg/kg-d); decreased serum thyroxine (BMDL = 0.93 mg/kg-d) without changes in some other hormones; and increased stillbirths (BMDL = 0.61 mg/kg-d PFNA). Pup weight and survival were not affected by PFNA exposure. Combined with data from previous studies, data from Peromyscus provide a One Health perspective on health effects of PFAS.

Quantitative read-across structure-activity relationship (q-RASAR): A novel approach to estimate the subchronic oral safety (NOAEL) of diverse organic chemicals in rats.

We have developed a quantitative safety prediction model for subchronic repeated doses of diverse organic chemicals on rats using the novel quantitative read-across structure-activity relationship (q-RASAR) approach, which uses similarity-based descriptors for predictive model generation. The experimental -Log (NOAEL) values have been used here as a potential indicator of oral subchronic safety on rats as it determines the maximum dose level for which no observed adverse effects of chemicals are found. A total of 186 data points of diverse organic chemicals have been used for the model generation using structural and physicochemical (0D-2D) descriptors. The read-across-derived similarity, error, and concordance measures (RASAR descriptors) have been extracted from the preliminary 0D-2D descriptors. Then, the combined pool of RASAR and the identified 0D-2D descriptors of the training set were employed to develop the final models by using the partial least squares (PLS) algorithm. The developed PLS model was rigorously validated by various internal and external validation metrics as suggested by the Organization for Economic Co-operation and Development (OECD). The final q-RASAR model is proven to be statistically sound, robust and externally predictive (R2 = 0.85, Q2LOO = 0.82 and Q2F1 = 0.94), superseding the internal as well as external predictivity of the corresponding quantitative structure-activity relationship (QSAR) model as well as previously reported subchronic repeated dose toxicity model found in the literature. In a nutshell, the q-RASAR is an effective approach that has the potential to be used as a good alternative way to improve external predictivity, interpretability, and transferability for subchronic oral safety prediction as well as ecotoxicity risk identification.

Nonclinical Safety Testing of RNA Vaccines.

In this chapter, we will first consider the overall goal of nonclinical safety testing during drug development and have a brief overview of its regulatory background. We will then discuss some basic requirements of safety/toxicity testing before concentrating on the safety testing of RNA vaccines and developing a sample RNA vaccine safety testing program.

Acute and sub-chronic toxicity study of novel polyherbal formulation in non-alcoholic fatty liver using Wistar rats.

Aim: This study assessed the acute and sub-chronic toxicity of a novel polyherbal formulation tablet in Wistar rats Materials & methods: Acute toxicity and sub-chronic toxicity was assessed following OECD (Organisation for the Economic Co-operation and Development) guidelines based on 423 and 408. Results & conclusion: No mortality and toxicity showed in rats during acute toxicity. The LD50 of the extract was at 2000 mg/kg. In sub-chronic study, both sex rats were orally administered at 250, 500,1000 and 2000 mg/kg for 90 days and revealed no significant difference (p < 0.05) in hematological and other parameters compared with the control. Histopathology study did not reveal morphological alteration. The No observed adverse effect level of the tablet was observed until 2000 mg/kg.

Non-alcoholic fatty liver disease (NAFLD) affects around 25% of individuals globally and has become the most common long-term liver problem. The reasons why people get this disease can be different for each person. By studying natural substances, scientists have discovered that some compounds help treat the disease some of these substances can also be harmful. By studying natural substances, scientists have discovered that some compounds help treat the disease some of these substances can also be harmful. People are also trying out traditional medicines more and more, and we need to make sure they're safe. To determine whether a medication is secure, we conducted experiments in accordance with the OECD guidelines. One test examines whether a high dose of the drug is lethal. The goal is to determine the optimal dose, which is neither too low nor too excessive. Another test investigated what happens if these rats take the medicine every day for a long time. Variables such as blood tests and tissue samples are collected to make sure the medicine does not make the rats sick. In this case, we tested a medicine called a 'PHF tablet' for 90 days, and it didn't make the animals sick. They found that you can take a relatively high dose without any adverse effects.

Safety, tolerability and toxicokinetics of the novel mitochondrial drug SUL-138 administered orally to rat and minipig.

Noncommunicable Chronic Diseases (NCD) are a socioeconomic burden and considered one of the major health challenges for coming decades. Mitochondrial dysfunction has been implicated mechanistically in their pathophysiology. Therefore, targeting mitochondria holds great promise to improve clinical outcomes in NCDs. SUL-138, an orally bioavailable small molecule efficacious from 0.5 mg/kg, improves mitochondrial function during disease in several preclinical animal models. As preparation for a First-in-Human (FIH) trial, SUL-138 was investigated in 30-day GLP repeated dose toxicity studies in rat and minipig, selected based on their comparability with human metabolism, to determine toxicokinetics, potential toxicity and its reversibility. Rats were allocated to either vehicle, 27, 136 or 682 mg/kg SUL-138 dose groups and minipigs were allocated to either vehicle, 16, 82 or 409 mg/kg. Treatment occurred orally for 30 days followed by a recovery period of 14 days. During these studies clinical observations, toxicokinetic, clinical pathology, necropsy and histopathology evaluations were performed. There was significant systemic exposure to SUL-138 and toxicokinetics was characterized by a rapid absorption and elimination. In the rat, toxicokinetics was dose-proportional and AUC0-tlast ratios in both species indicated that SUL-138 does not accumulate in vivo. No treatment-related adverse effects were observed for dose levels up to 136 and 82 mg/kg/day in rat and minipig respectively. In conclusion, these preclinical studies demonstrate that SUL-138 is well tolerated after repeated administration in rat and minipig, with NOAELs of 136 and 82 mg/kg/day, respectively.

Repeated dose toxicity studies of Trichostatin A in Swiss albino mice through oral and intravenous route of administration with special emphasis on genotoxicity.

Intravenous and oral 14 d repeated dose toxicity studies of Trichostatin A (TSA) were carried out in Swiss albino mice using low, intermediate, and high doses. Intravenous doses were 10, 25, and 50 µg/kg b.w while the oral doses were 20, 50, and 100 µg/kg b.w. Respective control groups of mice were administered phosphate buffered saline (vehicle only) for 14 consecutive days. All external morphological, hematological, biochemical, urine, histopathological, food intake in addition to body weight and vital organ weight were recorded. During the study no mortality in any animal was observed in either treatment routes. There were no significant changes in morphology, food intake, hematology, biochemical, urine analysis, organ weight. Animals treated high dose of TSA intravenously (50 µg/kg b.w) and orally (100 µg/kg b.w) had enlarged, congested, and discolored kidneys which were statistically significant. Histopathological studies had shown statistically significant degenerated glomerulus in high dose of intravenous and orally treated animals and degenerated tubule were found in orally treated animals. Genotoxicity was evaluated using micronucleus frequency at 14 and 21 d after treatment and chromosomal aberration at 21 d after treatment. Micronucleaus assay and chromosomal assay however did not show any significant changes at any doses and administration routes. Therefore, this study concludes that dose ∼25 µg/kg and ∼50 µg/kg b.w may be considered as No Observed Adverse Effect Level (NOAEL) for intravenous and oral administration of TSA respectively.

Safety assessment and gastrointestinal retention of orally administered cerium oxide nanoparticles in rats.

Cerium oxide nanoparticles (CeO2 NPs, NM-212) are well-known for their catalytic properties and antioxidant potential, and have many applications in various industries, drug delivery, and cosmetic formulations. CeO2 NPs exhibit strong antimicrobial activity and can be used to efficiently remove pathogens from different environments. However, knowledge of the toxicological evaluation of CeO2 NPs is too limited to support their safe use. In this study, CeO2 NPs were orally administered to Sprague Dawley rats for 13 weeks at the doses of 0, 10, 100, and 1000 mg/kg bw/day, followed by a four week recovery period. The hematology values for the absolute and relative reticulocyte counts in male rats treated with 1000 mg/kg bw/day CeO2 NPs were lower than those in control rats. The clinical chemistry values for sodium and chloride in the treated male rat groups (100 and 1000 mg/kg/day) and total protein and calcium in the treated female rat groups (100 mg/kg/day) were higher than those in the control groups. However, these changes were not consistent in both sexes, and no abnormalities were found in the corresponding pathological findings. The results showed no adverse effects on any of the parameters assessed. CeO2 NPs accumulated in the jejunum, colon, and stomach wall of rats administered 1000 mg/kg CeO2 NPs for 90 days. However, these changes were not abnormal in the corresponding histopathological and immunohistochemical examinations. Therefore, 1000 mg/kg bw/day may be considered the "no observed adverse effect level" of CeO2 NPs (NM-212) in male and female SD rats under the present experimental conditions.

Subjective biosafety assessment of bisdemethoxycurcumin from the rhizomes of Curcuma longa.

Introduction/Background: Curcuma longa, a plant native to the Indian subcontinent has a variety of biological activities. Curcumin is the most abundant and biologically active compound with many therapeutic properties. Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) - the two other bioactive components present in Curcuma longa, besides curcumin, are collectively termed curcuminoids. Apart from the well-known curcumin, BDMC also has been reported to possess promising biological and pharmacological effects, but very little scientific evidence on its safety assessment has been published.Objective: The present study was undertaken to determine the safety of pure BDMC from Curcuma longa extract in rodents which comprises of general toxicity (both four weeks and three months duration), reproductive/developmental toxicity and genotoxicity studies.Methods: The Good Laboratory Practice studies were carried out in accordance with the test guidelines established by the Organization for Economic Cooperation and Development.Results: No treatment-related adverse findings were seen in general toxicity testing and a no observed adverse effect level (NOAEL) of 1000 mg/kg/day was established after four weeks (sub-acute) and three-months (sub-chronic) dosing. Evaluation of fertility, embryo-fetal, and post-natal reproductive and developmental parameters also showed no adverse findings with a NOAEL of 1000 mg/kg/day established. The results of genotoxicity as evaluated by in vitro reverse mutation assay, and in vivo micronucleus test in mice indicate that BDMC did not induce any genotoxic effects.Conclusion: Oral administration of BDMC is safe in rodents and non-mutagenic, with no adverse effects under experimental conditions.

Continuous low-level dietary exposure to glyphosate elicits dose and sex-dependent synaptic and microglial adaptations in the rodent brain.

Prolonged exposure to low levels of dietary contaminants is a context in modern life that could alter organ physiology gradually. Here, we aimed to investigate the impact of continuous exposure to acceptable daily intake (ADI) and non-observable adverse effect level (NOAEL) of glyphosate from gestation to adulthood using C57BL/6J mice and incorporating these levels into their food pellets. From adulthood, we analyzed neurophysiological and neuro-glia cellular adaptations in male and female animals. Using ex-vivo hippocampal slice electrophysiology, we found a reduced efficacy of Schaffer collateral-to-CA1 excitatory synapses in glyphosate-exposed dietary conditions, with ADI and NOAEL dose-dependent effects. Short-term facilitation of excitatory synaptic transmission was specifically increased in NOAEL conditions, with a predominant influence in males, suggesting a reduced probability of neurotransmitter release. Long-term synaptic potentiation (LTP) was decreased in NOAEL-exposed mice. Next, we explore whether these neurophysiological modifications are associated with neuro-glia changes in the somatosensory cortex and hippocampus. High-resolution confocal microscopy analyses unveil a dose-dependent increased density of excitatory Vglut1+ Homer1+ synapses. Microglial Iba1+ cells displayed a shortening of their ramifications, a sign of cellular reactivity that was more pronounced in males at NOAEL levels. The morphology of GFAP+ astrocytes was generally not modified. Finally, we asked whether mouse-specific cross-correlations exist among all data sets generated. This examination included the novel object recognition (NOR) test performed before ex vivo functional and immunohistochemical examinations. We report a negative linear regression between the number of synapses and NOR or LTP maintenance when plotting ADI and NOAEL datasets. These results outline synaptic and microglial cell adaptations resulting from prenatal and continuous dietary low levels of glyphosate, discernible in, but not limited to, adult males exposed to the NOAEL. We discuss the potential significance of these findings to real-world consumer situations and long-term brain resilience.

Oral sub-chronic toxicity of fingerroot (Boesenbergia rotunda) rhizome extract formulation in Wistar rats.

Background: Boesenbergia rotunda (fingerroot) rhizome extract contains two major bioactive components, panduratin A and pinostrobin. In our previous study, we found the anti-inflammatory effects of the fingerroot extract against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in golden Syrian hamsters. In the present study, we evaluated the sub-chronic toxicity of a fingerroot extract formulation over 90 consecutive days of oral administration. Methods: We enhanced the water solubility of a fingerroot extract by formulating it with cyclodextrin, containing panduratin A (29% w/w) and pinostrobin (32% w/w). This formulation was administered to male and female Wistar rats at doses of 25, 50, or 100 mg/kg/day for a duration of 90 days. Additionally, two recovery groups, comprising a control group and a high-dose group, were designated for a 14-day observation period to assess the persistence and reversibility of potential adverse effects. Throughout the experiment, we performed clinical and health observations, followed by hematological testing, clinical biochemistry analysis, necropsy examination, and histopathological evaluation at the end of the experiment. Results: The administration of the fingerroot extract formulation at doses of 25, 50, or 100 mg/kg/day did not result in mortality or clinical signs of toxicity. No clinically significant findings were associated with the oral administration of the fingerroot extract formulation. Conclusion: The fingerroot extract formulation showed no serious adverse effects at doses up to 100 mg/kg/day in Wistar rats under the experimental condition. Consequently, the No Observed Adverse Effect Level (NOAEL) was considered to be 100 mg/kg/day. This finding contributes significance for future developments involving fingerroot extract in herbal medicinal products targeting chronic inflammation.

Toxicity and Toxicokinetics of a Four-Week Repeated Gavage of Levamisole in Male Beagle Dogs: A Good Laboratory Practice Study.

Levamisole (LVM) is considered an immunomodulatory agent that has the potential to treat various cancer and inflammation diseases. However, there is still much debate surrounding the toxicokinetic and toxicological information of LVM. Therefore, it is crucial to assess its toxicity to provide useful data for future human LVM risk assessments. In this study, a barrier environment was established under the guidance of good laboratory practice (GLP) at the Fujian Center for New Drug Safety Evaluation. Male beagle dogs were orally administered with 5, 15, and 30 mg/kg of LVM daily for four weeks. Toxicity assessment was based on various factors such as mortality, clinical signs, food and water consumption, body weight, body temperature, electrocardiogram, ophthalmological examination, hematology, serum biochemistry, organ/body coefficients, histopathological study, and toxicokinetic analysis. The results of this study showed that LVM did not exhibit any significant toxicological effects on beagle dogs at the exposure levels tested. A no observed adverse effect level (NOAEL) of LVM was set at 30 mg/kg/day for male beagle dogs, which is equivalent to a 12-fold clinical dose in humans. Moreover, the repeated exposure to LVM for four weeks did not lead to any bioaccumulation. These findings provide valuable insights for future human LVM risk assessments.

Comprehensive safety assessment of serendipity berry sweet protein produced from Komagataella phaffii.

Serendipity berry plant (Dioscoreophyllum cumminsii (Stapf) Diels) is the source of a naturally sweet protein referred to as monellin. The safety of serendipity berry sweet protein (SBSP) containing single polypeptide monellin (MON) expressed in Komagataella phaffii (formerly Pichia pastoris) and produced via precision fermentation was examined comprehensively through assessments of in vitro and in silico protein digestion, in silico allergenicity, in vitro genotoxicity (reverse mutation and mammalian micronucleus assays), and 14-day and 90-day oral (dietary) toxicity studies in rats. There was no indication of allergenicity for SBSP in the in silico analyses. Results from both in vitro and in silico protein digestibility assessments indicated that SBSP is digested upon ingestion and would therefore be unlikely to pose a toxigenic or allergenic risk to consumers. SBSP was non-genotoxic in in vitro assays and showed no adverse effects in the 14-day or 90-day toxicity studies up to the highest dose tested. The 90-day toxicity study supports a NOAEL for SBSP of 1954 mg/kg bw/day, which corresponds to a NOAEL for MON of 408 mg/kg bw/day.

Acute and chronic toxicity in Sprague-Dawley rats of orally-administered total lignans from Arctii Fructus, a potential therapeutic drug for diabetes.

Arctii Fructus is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is in the Chinese pharmacopoeia. Previous research showed that the total lignans from Arctii Fructus (TLAF) have pharmacological activities related to diabetes. This study evaluated the acute and chronic (26 weeks) toxicities associated with oral daily administration of TLAF in Sprague-Dawley (SD) rats. An acute-toxicity test showed that TLAF caused 10% mortality at 3,000 mg/kg × 2 (6-h interval), with toxic symptoms, such as dyspnea and tonic convulsions, indicating potential neurotoxicity. A chronic-toxicity study showed no mortality after administration. The no observed adverse-effect level was 1,800 mg/kg (approximately 54 times higher than the human clinical dose) for 26 weeks of TLAF oral administration in SD rats, with toxicity signs of excessive oral and nasal secretions and moist circumferential hair that recovered after TLAF discontinuation. In the toxicokinetic study, the two main components of TLAF, arctigenin plasma level was positively correlated with dose and tended to accumulate after multiple doses. At 1,800 mg/kg, arctiin plasma level increased and tended to accumulate after multiple doses. These results indicated that TLFA has relatively low toxicity and the potential for clinical treatment of diabetes.