Evaluation of arsenic induced genotoxicity and its impact on life processes of Daphnia magna.

Heavy metals like arsenic is ubiquitously present in the environment. Geologic and anthropogenic activities are the root cause behind high concentration of arsenic in natural water bodies demanding strict monitoring of water quality prior to human consumption and utilization. In the present study, we have employed Daphnia magna for studying the biological effects of environmentally relevant high concentration of arsenic in water. In acute toxicity study, the LC50 value for 24hr exposure was found to be 2.504 mg/L, which gradually decreased with increase in time period (24hr- 96hr) to 2.011 mg/ L at 96hr. Sub-chronic toxicity was evaluated over 12 days using sub-lethal concentrations (5 %, 10 %, 15 %, and 20 % of the 24-hr LC50). Survivability in Daphnia showed a decreasing trend from 96 % to 91 % with increase in arsenic concentrations from 5 % of LC50 24 hr value to 20 % of LC 50 24hr value respectively. Alongside decreased survivability, there was a significant reduction in body size, with organisms exposed to the highest concentration of arsenic measuring 0.87±0.01 mm compared to 1.51±0.10 mm in the control group. Reproductive potential declined concentration dependently with exposure, with the highest reduction observed at 20 % of LC50 24hr value, where offspring numbers decreased to 7±1 from 23±5 in the control. Heart rate decreased in concentration and time-dependent manners, with the lowest rates observed at the highest arsenic concentration (279±16 bpm after 24hr and 277±27 bpm after 48hr). Comet assay and micronucleus assay conducted after 48 hrs of exposure revealed concentration-dependent genotoxic effects in Daphnia magna. Our results indicate negative impact on physiology and reproduction of Daphnia magna at environmentally existent concentration of arsenic. Also Daphnia magna could serve as a sensitive test system for investigating arsenic contamination in water bodies.

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.

Bacillus subtilis ZB423: 90-Day repeat dose oral (gavage) toxicity study in Wistar rats.

The novel genetically modified probiotic Bacillus subtilis ZB423 was assessed in a 90-day repeated-dose oral toxicity study adhering to Good Laboratory Practice (GLP) and Organization for Economic Cooperation and Development (OECD) guidelines. Spray-dried spores at a concentration of 1.1E12 CFU/g were administered at doses of 130, 260, and 519 mg/kg body weight/day correlating to 1.43 × 1011, 2.86 × 1011, and 5.71 × 1011 CFU/kg/day, respectively, by oral gavage to Wistar rats for a period of 90 consecutive days. Results showed no toxicologically relevant findings for B. subtilis ZB423 from measured parameters. The no observed adverse effect level (NOAEL) of B. subtilis ZB423 is 519 mg/kg body weight/day corresponding to 5.71 × 1011 CFU/kg/day for lyophilized B. subtilis ZB423 spores under the test conditions employed.

Hepatic and metabolic outcomes induced by sub-chronic exposure to polystyrene microplastics in mice.

Microplastics (MPs) have attracted significant attention due to their global distribution in living environments. Although some studies have reported MP-induced hepatotoxicity in mouse models, a systematic approach to MP-mediated liver toxicity was still lacking. Therefore, we used a mouse model to study the sub-chronic effects of MP exposure on the liver. Female C57BL/6 mice, aged 6 weeks, received an oral administration of 0.3 mg of Nile Red-labeled polystyrene (PS) microplastics, with particle sizes of 0.5 µm (submicron) and 5 µm (micron), via gavage, while control mice received vehicle only. Each mouse was exposed to MPs twice a week for 12 weeks. After sacrifice, the levels of MP accumulation, oxidative stress, inflammation, and pathological changes were measured in the mouse liver, and blood samples were collected for serum biochemistry analysis. Our results demonstrated that 0.5 µm PS-MPs were accumulated in mouse livers post-MP exposure, but not in the 5 µm MP exposure group. Simultaneously, increased levels of glucose, triglyceride, alanine transaminase (ALT), aspartate transaminase (AST), superoxide dismutase, 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), interleukin-6, and lipid droplets were found in the 0.5 µm MP exposure group, while the fewer responses, including elevated liver weight index, glucose, high-density lipoprotein, AST, and decreased HNE-MA were observed in 5 µm MP exposure group. These results indicate that sub-chronic exposure to submicron MPs causes MP deposition in mouse livers, which further induces oxidative stress, increases inflammatory cytokines and perturbs glucose and lipid homeostasis, which might trigger more severe metabolic dysfunction or non-alcoholic steatohepatitis-like hepatotoxicity.

Synthesis of glucosamine-selenium compound and evaluation of its oral toxicity and in vitro anti-hepatitis B virus activity.

Selenium supplements are beneficial to human health, however, concerns regarding the toxicity of inorganic selenium have stimulated research on safer organic compounds. The main objective of this study was to develop a novel glucosamine-selenium compound (Se-GlcN), clarify its structure, and subsequently investigate its oral toxicity and in vitro anti-hepatitis B virus (HBV) activity. Electron microscopy, infrared, ultraviolet spectroscopy, nuclear magnetic resonance and thermogravimetric analyses revealed a unique binding mode of Se-GlcN, with the introduction of the Se-O bond at the C6 position, resulting in the formation of two carboxyl groups. In acute toxicity studies, the median lethal dose (LD50) of Se-GlcN in ICR mice was 92.31 mg/kg body weight (BW), with a 95 % confidence interval of 81.88-104.07 mg/kg BW. A 30-day subchronic toxicity study showed that 46.16 mg/kg BW Se-GlcN caused livers and kidneys damage in mice, whereas doses of 9.23 mg/kg BW and lower were safe for the livers and kidneys. In vitro studies, Se-GlcN at 1.25 µg/mL exhibited good anti-HBV activity, significantly reducing HBsAg, HBeAg, 3.5 kb HBV RNA and total HBV RNA by 45 %, 54 %, 84 %, 87 %, respectively. In conclusion, the Se-GlcN synthesized in this study provides potential possibilities and theoretical references for its use as an organic selenium supplement.

Safety evaluation of aqueous extract from Valeriana officinalis L. roots: Genotoxicity, acute, subchronic and teratology toxicity.

ETHNOPHARMACOLOGICAL RELEVANCE: Valeriana officinalis L., commonly known as "valerian", is a traditional herbal medicine distributed in the north temperate zones of America, Europe and Asia. In traditional Chinese medicine, valerian and its roots were used for the treatment of restlessness of the heart and mind, palpitation and insomnia caused by internal depression of emotions and moods. However, safety evaluation of valerian remains deeply unclear. AIM OF THE STUDY: This study aimed to evaluate the genotoxicity, 14-days acute oral toxicity test, 90-day subchronic oral toxicity test and teratogenicity test of aqueous extract of valerian root (AEVR). MATERIALS AND METHODS: The genotoxicity of AEVR was evaluated with bacterial reverse mutation, mouse erythrocyte micronucleus test and in vitro mammalian cell chromosome aberration test. In the 14-days acute toxicity study, Kunming mice were administered at a dosage of 96 g/kg body weigh by gavage. In the 90-day subchronic toxicity study, Sprague-Dawley rats received oral doses of 0, 3.5, 7 and 14 g/kg body weight of AEVR. In the teratogenicity study, pregnant Sprague-Dawley rats received a dose of 0, 3.5, 7 and 14 g/kg body weight of AEVR. RESULTS: AEVR did not show any genotoxicity based on the bacterial reverse mutation, mouse erythrocyte micronucleus test and in vitro mammalian cell chromosome aberration test. In the acute toxicity study, AEVR at a dose of 96 g/kg body weight did not cause death or abnormal behavior in male or female mice. In the subchronic toxicity study, at the doses of 0, 3.5, 7, 14 g/kg body weight, no dose-related effects on clinical observation, body weight, organ weight, hematology, serum biochemistry and urinalysis of AEVR were detected in male or female rats. Teratogenicity test shown that there were no significant toxicologically changes in embryonic formation, body weight of pregnant rats, external, skeletal and visceral examination observed in pregnant and fetal rats at the dosage of 0, 3.5, 7, 14 g/kg body weight. CONCLUSION: In vivo or in vitro assays demonstrated that AEVR does not exhibit genotoxicity. The LD50 of AEVR was greater than 96 g/kg body weight in both sex of mice according to acute oral toxicity study. Subchronic toxicity and teratogenicity tests showed that the no observed adverse effect level (NOAEL) of AEVR was no less than 14 g/kg body weight. This study established a non-toxic dose of AEVR, providing a foundation for the use of valerian as a new resource food in some countries and regions.

Study on the acute and subchronic oral toxicity of Calculus Bovis Sativus in rats.

This study aims to assess the acute and subchronic toxicity of Calculus Bovis Sativus (CBS), which is an ideal substitute for natural Calculus Bovis. After conducting a test of acute toxicity with KM mice of both sexes, it was determined that oral CBS had a lethal dosage (LD50) of greater than 9.26 g/kg BW. For ninety days, Wistar rats were fed on CBS orally at dosages of 0, 167, 501, and 1503 mg/kg BW/day, respectively, as part of the subchronic investigation. A comparison of the controls with the 1503 mg/kg and 501 mg/kg dosage groups revealed significant differences in the hematological and serum biochemical parameters, such as RBC, HGB, MONO%, PLT, LYMPH% and GLU, TP, ALB, and Ca2+, were observed. However, values of the above parameters fell within our laboratory's normal range. In terms of body weight, food intake, urinalysis, clinical chemistry, and pathology, no other adverse effects were observed. After 90 days of exposure, the no observed adverse effect level (NOAEL) of CBS in rats was determined to be 1503 mg/kg BW/day.

Effects of α-olefin sulfonate (AOS) on Tubifex tubifex: toxicodynamic-toxicokinetic inferences from the general unified threshold (GUTS) model, biomarker responses and molecular docking predictions.

We investigated the potential ecological risks and harm to aquatic organisms posed by anionic surfactants such as α-olefin sulfonate (AOS), which are commonly found in industrial and consumer products, including detergents. This study assessed acute (96-h) and subchronic (14-day) responses using antioxidant activity, protein levels, and histopathological changes in Tubifex tubifex exposed to different AOS concentrations (10% of the LC50, 20% of the LC50, and a control). Molecular docking was used to investigate the potential interactions between the key stress biomarker enzymes (superoxide dismutase, catalase, and cytochrome c oxidase) of Tubifex tubifex. Acute AOS exposure showed a concentration-dependent decrease in survival, and the general unified threshold (GUTS) model revealed that survivorship is linked to individual response patterns rather than random (stochastic) fluctuations. The GUTS model also revealed dose-dependent toxicity patterns in Tubifex tubifex exposed to α-olefin sulfonate (AOS), with adaptive mechanisms at lower concentrations but significant increases in mortality beyond a certain threshold, emphasizing the role of the AOS concentration in shaping its toxicological impact. Exposure to AOS disrupted antioxidant activity, inducing oxidative stress, with GST and GPx showing positive associations with surfactant concentration and increased lipid peroxidation (elevated MDA levels); moreover, AOS exposure decreased protein concentration, signifying disturbances in vital cellular processes. Histopathological examinations revealed various tissue-level alterations, including cellular vacuolation, cytoplasmic swelling, inflammation, necrosis, and apoptosis. Molecular docking analysis demonstrated interactions between AOS and enzymes (-catalase, superoxide dismutase, and cytochrome c oxidase) in Tubifex tubifex, including hydrophobic and hydrogen bond interactions, with the potential to disrupt enzyme structures and activities, leading to cellular process disruptions, oxidative stress, and tissue damage. According to the species sensitivity distribution (SSD), the difference in toxicity between Tilapia melanopleura (higher sensitivity) and Daphnia magna (low sensitivity) to AOS suggests distinct toxicokinetic and toxicodynamic mechanisms attributable to more complex physiology in Tilapia and efficient detoxification in Daphnia due to its smaller size.

Genotoxicity of Formaldehyde: Effect of Whole-Body Exposure on Polychromatic Erythrocyte/Normochromatic Erythrocyte Ratio in Male and Female Rats.

Every day, millions of individuals are exposed to formaldehyde (FA) due to its extensive presence and versatile use. Many in vivoand in vitroexperiments revealed that the mechanism of genotoxicity induced by FA exposure is complex yet toxicity upon whole-body exposure (WBE) to FA is less. As teachers, students, and skilled assistants in the health care sectors are also extensively exposed to FA vapors, it might result in genotoxicity. However, the effects of subchronic exposure to FA at low concentrations are not clear. Hence, analysis of the micronucleus (MN) was necessary to study the genetic toxicity triggered by FA in the bone marrow of male and female experimental rats. The present study is a gender- and duration of exposure-based assessment of the geno- and cytotoxicity in bone marrow cells of Wistar rats to study the effect of WBE to 10% FA on polychromatic erythrocytes/normochromatic erythrocytes (PCE/NCE) ratio and micronucleated polychromatic erythrocytes (MnPCE) in experimental rats. The obtained result clearly showed that WBE to FA for 60 days at concentrations between 1 and 1.1 ppm (0, 1, and 1.5 h) induced genotoxic effects in both male and female rats by altering the MnPCE% and significantly increasing the ratio of PCE/NCE (1.07 ± 0.23, 1.20 ± 0.20, 1.22 ± 0.14). The PCE/NCE ratio in male rats was lesser (0.98, 1.12, and 1.18) when compared with female rats (1.17, 1.29, and 1.26) with 0, 1, and 1.5 h exposure, respectively. Thus, the genetic/cellular sensitivity to FA differs among the sexes and also depends on the exposure duration.

Non-clinical Safety Evaluation of Camelina Oil: Acute and 12-Week Oral Toxicities.

This study assessed the acute and sub-chronic toxicity of Camelina oil, a well-known oil rich in polyunsaturated fatty acids that enhance cellular immunity and human health, in Wistar rats. Wistar rats, 5 per sex per group, were randomly assigned to three groups for acute (14 days) toxicity studies and five groups for sub-chronic (90 days) toxicity studies. In the acute study, Camelina sativa oil was administered orally at a single dose of 5000 mg/kg of body weight (BW). The positive control group received a single dose of 5 000 mg/kg BW Canola oil by gavage. In the sub-chronic study, Groups III-V received 250, 500, and 1 000 mg/kg BW of Camelina oil, while Groups I and II received ultra-pure water and Canola oil at a dose of 500 mg/kg BW, respectively. Throughout the experiment, clinical signs, mortality, and body weight were monitored. At the end of the sub-chronic study, hematological, biochemical, and histopathological investigations were conducted. Administration of Camelina oil and Canola had no significant effect on daily weight gain (P > 0.05) of the test rats. Serum calcium levels decreased while phosphorous levels increased in male rats treated with Camelina oil. Other hematological and biochemical parameters showed no significant differences or dose-response effects between control and seed oil groups in both sexes (P < 0.05). Moreover, in animal necropsy, there were no apparent lesions in the liver, heart, and kidney organs in any of the doses administered. In conclusion, the results suggest that oral administration of Camelina oil is unlikely to be toxic. Therefore, the possibility for the development of future human nutrition should be considered.

Sub-chronic toxicity of the active fraction of a modified Huang-Lian-Jie-Du Decoction.

A traditional Chinese herbal medicine formula named Huang-Lian-Jie-Du Decoction (HLJDD) has been used to cure various inflammatory diseases with a long history. However, one component of HLJDD Gardeniae fructus has remarkable liver and kidney toxicities. Therefore, it was altered with Dictamni cortex to form a modified HLJDD (MHLJDD). In this study, we aimed to evaluate the sub-chronic toxicity of the active fraction of MHLJDD (MHLJDD-F) in rats. Adult rats of both sexes were intragastrically administered with vehicle or MHLJDD-F (at the dose of 170, 340, and 680 mg/kg/day) once daily for 90 days. Half of the rats from each group were kept for an additional 30-day period to observe the drug withdrawal effect. The signs of toxicity and mortality of the rats were observed, and the body weight and food consumption were recorded. Blood was collected for hematological and biochemical analyses and major organs were weighed and harvested for histopathological examinations. The results revealed that no systemic toxicity of MHLJDD-F was found during the experiments. Organ coefficients and pathological alterations of major organs were comparable to the control rats. The no-observed adverse effect level (NOAEL) of MHLJDD-F was found up to 680 mg/kg/day. All these results demonstrated that long-term oral administration of MHLJDD-F did not cause significant toxicity, which is worthy to be widely applied as a new herbal medicine in pre-clinical and clinical studies.

Toxicological safety assessment of a water extract of Lithocarpus litseifolius by a 90-day repeated oral toxicity study in rats.

Lithocarpus litseifolius although known as "Sweet Tea" (ST), has been traditionally accepted as a daily beverage and used as a folk medicine in southern China with little understanding of its potential toxicity. This study evaluated the safety of a water extract of ST by a subchronic toxicity study in Sprague-Dawley rats. A total of 80 rats were randomized divided into 4 groups with 10 males and 10 females in each group, treated with 2000, 1,000, 500 and 0 mg/kg body weight of ST extract by gavage for 90 days, respectively. The results of the study showed that ST extract did not induce treatment-related changes in the body and organ weight, food intake, blood hematology and serum biochemistry, urine indices, and histopathology in rats. The NOAEL of ST extract was observed to be 2000 mg/kg/day for rats of both sexes. These results indicated that ST extract was of low toxicity in the experimental conditions of the current study and had the potential for application in food-related products.

Juvenile bright light exposure ameliorates adult behavioral abnormalities by enhancing neurogenesis in a N-methyl-D-aspartate receptor dysfunction mouse model relevant for cognitive impairment in schizophrenia.

Exposure to light has been demonstrated to stimulate brain regions associated with cognition; however, investigations into its cognitive-enhancing effects have primarily focused on wild-type rodents. This study seeks to elucidate how bright light exposure mitigates cognitive deficits associated with schizophrenia by examining its impact on hippocampal neurogenesis and its potential to alleviate sub-chronic MK-801-induced cognitive impairments in mice. Following three weeks of juvenile bright light exposure (5-8 weeks old), significant increases in proliferating neurons (BrdU+) and immature neurons (DCX+ cells) were observed in the dentate gyrus (DG) and lateral ventricle of MK-801-treated mice. Long-term bright light treatment further promoted the differentiation of BrdU+ cells into immature neurons (BrdU+ DCX+ cells), mature neurons (BrdU+ NeuN+ cells), or astrocytes (BrdU+ GFAP+ cells) in the hippocampal DG. This augmented neurogenesis correlated with the attenuation of sub-chronic MK- 801-induced cognitive deficits, as evidenced by enhancements in Y-maze, novel object recognition (NOR), novel location recognition (NLR), and Morris water maze (MWM) test performances. These findings suggest a promising noninvasive clinical approach for alleviating cognitive impairments associated with neuropsychiatric disorders.

The investigation on an ethnic medicinal plant of Elsholtiza bodinieri Vaniot: Chemical constituents, acute, 28-day subacute and 90-day subchronic toxicity evaluation.

ETHNOPHARMACOLOGICAL SIGNIFICANCE: Elsholtiza bodinieri Vaniot, belonging to the family Lamiaceae, has important medicinal value in Yunnan province of China. Traditionally, its aerial parts have been used as an ethnomedicine to treat diaphoresis, headache, fever, cough, pharyngitis, dyspepsia, and hepatitis. However, the safety assessment of E. bodinieri is still unexplored. AIM OF THE STUDY: This study aimed to investigate the phytochemical constituents of the hot water extract from E. bodinieri (HEEB) and evaluate the 14-day acute, 28-day subacute and 90-day subchronic toxicity by oral administration in Sprague-Dawley (SD) rats. MATERIALS AND METHODS: The chemical constituents of HEEB were analyzed by UHPLC-ESI-HRMS/MS. Firstly, SD rats were chosen for a single oral administration of the maximum dose of 5000 mg/kg to evaluate toxicity. Subsequently, consecutive 28-day subacute and 90-day subchronic toxicity assessments of HEEB were conducted on Sprague-Dawley (SD) rats through repeated doses of 2500, 1250, 625, and 312.5 mg/kg for the former, and 1500, 1000, and 500 mg/kg for the latter. For toxicity evaluation, hematology and serum biochemical indicators were determined, and major organs of the rats were collected to calculate organ coefficients. Additionally, hematoxylin-eosin (H&E) staining was performed on the collected tissues to assess histopathological changes induced by repeated oral administration of HEEB. RESULTS: A total of 23 compounds were identified by UHPLC-ESI-HRMS/MS analysis. Acute toxicity assessment revealed that oral administration of HEEB did not induce mortality and unnormal behavior changes in female rats over a 14-day period, suggesting that the approximate lethal dose (ALD) was higher than 5000 mg/kg. In consecutive 28-day and 90-day toxicity evaluations, HEEB doses of 2500 mg/kg and 1500 mg/kg resulted in hepatic and kidney tissue damage in both female and male rats, which was verified by the increased levels of AST, ALT, BUN, Na+, and Cl-. CONCLUSIONS: After the acute, 28-day subacute and 90-day subchronic toxicity evaluation, the No Observed Adverse Effect Level (NOAEL) was determined as 1000 mg/kg/day. These findings not only provided a safety information for its medicinal and edible application, but also promoted the further comprehensive development of this plant.

Effect of Zinc Supplementation on Altered Calcium Homeostasis, Parathyroid Gland, Bone, and Skeletal Muscle Histology Induced by Subchronic Oral Exposure to Glyphosate-Based Herbicide (GOBARA®) in Wistar Rats.

Objectives: The study was carried out to assess the effect of zinc supplementation on changes in calcium homeostasis, and parathyroid gland, bone, and skeletal muscle histology in rats exposed to subchronic oral glyphosate-based herbicide (GBH, GOBARA®) toxicity. Methods: Sixty male Wistar rats in 6 equal groups (DW, Z, G1, G2, ZG1, ZG2) were used: DW and Z were given 2 mL/kg distilled water and 50 mg/kg of zinc chloride (2%), respectively; G1 and G2 received 187.5 mg/kg and 375 mg/kg of glyphosate (in GBH), respectively; ZG1 and ZG2 were pretreated with 50 mg/kg of zinc chloride before receiving glyphosate, 1 hour later, at 187.5 and 375 mg/kg, respectively. Treatments were by gavage once daily for 16 weeks. Serum calcium, vitamin D, and parathormone were estimated. Histopathological examination of parathyroid gland, femoral bone and biceps femoris muscle was done. Results: GBH exposure caused significant (P = .0038) decrease in serum calcium concentration in G1, significant (P = .0337) decrease in serum vitamin D concentration in G1, significant increases in parathormone in G1 (P = .0168) and G2 (P = .0079) compared to DW. Significant (P > .05) changes did not occur in the other parameters of G2 compared to DW. Dose-dependent effect in GBH exposure was not observed after comparing G1 and G2. Necrotic changes occurred in parathyroid gland cells, osteocytes, and muscle cells in G1 and G2. In ZG1 and ZG2, significant (P > .05) variations in the parameters were not observed and tissue lesions were absent. Conclusion: Subchronic GBH exposure impaired calcium homeostasis observed as hypocalcemia, hypovitaminemia D, and secondary hyperparathyroidism and caused tissue damage in parathyroid gland, bone, and muscle of rats and these were mitigated by zinc chloride pretreatment.

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.

Toxicological evaluation of porcine bile powder in Kunming mice and Sprague-Dawley rats.

Background: Porcine bile powder (PBP) is a traditional Chinese medicine that has been used for centuries in various therapeutic applications. However, PBP has not previously undergone comprehensive component analysis and not been evaluated for safety through standard in vivo toxicological studies. Methods: In our study, we characterized the component of PBP by liquid chromatography-mass spectrometry. The acute and subchronic oral toxicity, genotoxicity, and teratogenicity studies of PBP were designed and conducted in Kunming mice and Sprague-Dawley (SD) rats. Results: The chemical analysis of PBP showed that the main components of PBP were bile acids (BAs), especially glycochenodeoxycholic acid. There were no signs of toxicity observed in the acute oral test and the subchronic test. In the genotoxicity tests, no positive results were observed in the bacterial reverse mutation test. Additionally, in the mammalian micronucleus test and mouse spermatocyte chromosomal aberration test, no abnormal chromosomes were observed. In the teratogenicity test, no abnormal fetal development was observed. Conclusion: Our findings demonstrate that PBP, composed mainly of BAs, is non-toxic and safe based on the conditions tested in this study.

Noradrenergic Regulation of the Medial Prefrontal Cortex Mediates Stress Coping in Postpartum Female Mice.

The prevalence of depression in women increases during the postpartum period. We previously reported that subchronic exposure to social stress decreased passive coping in postpartum female mice. This study aimed to investigate whether noradrenaline regulation might regulate coping styles in mice. We first determined whether a different type of stress, subchronic physical stress, decreases passive coping in postpartum females. Postpartum female, virgin female, and male mice were exposed to subchronic restraint stress (restraint stress for 4 h for 5 consecutive days). Subchronic restraint stress decreased passive coping in postpartum females but not in virgin females and males in the forced swim and tail suspension tests. We next examined the neuronal mechanism by which subchronic stress decreases passive coping in postpartum female mice. Neuronal activity and expression of noradrenergic receptors in the medial prefrontal cortex (mPFC) were analyzed using immunohistochemistry and reverse transcription-quantitative polymerase chain reaction, respectively. The mPFC was manipulated using chemogenetics, knockdown, or an α2A adrenergic receptor (AR) antagonist. Immunohistochemistry revealed that subchronic restraint stress increased glutamatergic neuron activation in the mPFC via forced swim stress and decreased α2A AR expression in postpartum females. Chemogenetic activation of glutamatergic neurons in the mPFC, knockdown of α2AAR in the mPFC, and the α2A AR receptor antagonist atipamezole treatment decreased passive coping in postpartum females. Subchronic restraint stress decreased passive coping in postpartum females by increasing glutamatergic neuron activity in the mPFC through α2A AR attenuation. The noradrenergic regulation of the mPFC may be a new target for treating postpartum depression.

Toxicity assessment of Cucurbita pepo cv Dayangua and its effects on gut microbiota in mice.

BACKGROUND: Cucurbita pepo cv Dayangua (CPD) is an edible plant with diverse pharmacological properties. The current research on CPD has primarily focused on initial investigations of its chemical composition and pharmacological effects, and no comprehensive toxicity assessment has been conducted to date. METHODS: In the present study, the toxicity of CPD was evaluated through both acute and sub-chronic oral toxicity tests in mice. 16S rDNA sequencing was used to analyze the composition of the gut microbiota of mice at different time points to observe the effect of CPD on these microbial communities. RESULTS: In the acute toxicity test, CPD exhibited low toxicity, with a median lethal dose (LD50) > 2000 mg/kg. The sub-chronic toxicity test indicated that CPD administration at doses of 200, 400, and 600 mg/kg did not cause mortality or significant organ damage in mice. Furthermore, analysis of the gut microbiota after gavage administration of CPD at 400 and 600 mg/kg revealed an improved abundance of some beneficial gut bacteria. CONCLUSIONS: In summary, no acute or sub-chronic toxic effects were observed in mice following the oral administration of CPD. CPD did not affect the structure and diversity of the gut microbiota and may contribute to an increase in the number of beneficial gut bacteria.

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.