No-observed-adverse-effect Level Research Articles

TOXICOLOGICAL EVALUATION OF OLEANOLIC ACID (PENTACYCLIC TRITERPENOID) EXTRACTED FROM LANTANA CAMARA ROOTS FOLLOWING ORAL EXPOSURE IN WISTAR RATS

Objective: The aim of the present study was to perform an acute toxicity study to obtain information on the possible adverse effects from a single oral administration of Oleanolic acid in Wistar rats as the onset of toxicity, and to determine the range of exposure (to the LD50 cut-off criteria). Following a sub-chronic 90-days Repeated toxicity study by oral route to determine any potential indication of its dose response relationship and determine no observed effect level (NOEL)/ no-observed adverse effect level (NOAEL)/ low observed effect level (LOEL)/ low observed adverse effect level (LOAEL). Methods: A dose level of 2000mg/kg body weight was employed as step one for single acute study. Based on the survival pattern of the previously dosed animals after 48 hours, same dose 2000 mg/kg body weight) was repeated for Step 2 as a confirmatory test. For the 90-day toxicity study, the highest dose was determined as 1000mg/kg Body weight, and the middle and lower doses were 500 and 250mg/kg Body weight respectively. The rat group was held for a 14-day recovery period after the last dose administration, to observe for any persistence or reversal of toxic effects. Results: Results of the acute toxicity study showed no mortality on the dose level of 2000mg/kg body weight with no significant clinical and body weight changes. During the 90-day Repeated dose oral sub-chronic toxicity study, no rats died. There were no significant clinical changes related to the test item in terms of functional evaluation, body weight, food and water consumption, ophthalmological tests, urine analysis, necropsy findings, or organ weight, Hematology, and biochemistry at the highest dose level of 1000 mg/kg bwt. Conclusion: It is concluded that LD50 Cut-off Value of “Oleanolic acid” in from acute oral toxicity study in Wistar Rats is 2000 mg/kg b.wt. In addition, 90 days study have showed no significant changes with respect to any hematological or blood chemical analyses in 1000, 500 and 250 mg/kg bwt groups. Based on histopathological findings, clinical signs and other parameters, it may be concluded that upon repeated once oral administration for consecutive 90 days, the Oleanolic acid (Pentacyclic Triterpenoid) extracted from Lantana camara roots at the dose level of 1000 mg/kg body weight have caused no adverse effect in both sexes of Wistar Rats.

Preclinical characterization of a novel investigational monoclonal antibody CM313 with potent CD38-positive cell killing activity

IntroductionCM313 is currently under clinical investigation for treatments of multiple myeloma, systemic lupus erythematosus, and immune thrombocytopenia. We aimed to report the preclinical profile of the novel therapeutic anti-CD38 monoclonal antibody (mAb) CM313, with an emphasis on the difference with other CD38-targeting mAb.MethodsThe binding of CM313 to CD38 recombinant protein across species was assessed using ELISA. The binding of CM313 to CD38-positive (CD38+) cells was detected using flow cytometry assays. CM313-induced complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and apoptosis on different CD38+ cells were assessed by LDH release assays or flow cytometry assays. The effect of CM313 on CD38 enzymatic activity was measured using fluorescence spectroscopy. CM313 immunotoxicity in human blood was assessed using flow cytometry assays, ELISA, and LDH release assays. Anti-tumor activity of CM313 was assessed in multiple mouse xenograft models. Safety profile of CM313 were evaluated in cynomolgus monkeys and human CD38 transgenic (B-hCD38) mice.ResultsThere exist unique sequences at complementarity-determining regions (CDR) of CM313, which facilitates its affinity to CD38 is consistently higher across a spectrum of CD38+ cell lines than daratumumab. In vitro studies showed that CM313 induces comparable killing activity than daratumumab, including ADCC, CDC, ADCP, apoptosis induced by Fc-mediated cross-linking, and effectively inhibited the enzymatic activity of CD38. However, CM313 showed more potent CDC than isatuximab. In vivo, CM313 dose-dependently inhibited xenograft tumor growth, both as a monotherapy and in combination with dexamethasone or lenalidomide. Furthermore, CM313 was well tolerated with no drug-related clinical signs or off-target risks, as evidenced by 4-week repeat-dose toxicology studies in cynomolgus monkeys and B-hCD38 mice, with the later study showing no observed adverse effect level (NOAEL) of 300mg/kg once weekly.DiscussionCM313 is a novel investigational humanized mAb with a distinct CDR sequence, showing comparable killing effects with daratumumab and stronger CDC activity than isatuximab, which supports its clinical development.

In silico predictions of sub-chronic effects: Read-across using metabolic relationships between parents and transformation products

Justifying read-across predictions for subchronic effects, such as no observed adverse effect levels (NOAEL), is challenging. The scarcity of suitable experimental data hampers such predictions, such that a conservative approach is often employed where the structural similarity between target and the tested source substances is very high. A less stringent interpretation of structural similarity may be used to expand data gap-filling by read-across if other types of similarity (e.g., toxicokinetic and toxicodynamic consideration) are factored into the justification. Herein, qualitative and quantitative in silico-assisted procedures are described and demonstrated for those instances where no structurally similar analogues are identified. In the qualitative approach, the toxicity classification of the most toxic metabolite is assigned directly to the target compound. While simple, this approach may lead to an over-classification of the target compound and a false positive result. In contrast, the quantitative approach is more complicated. In addition to identifying those metabolites causing toxicity, it examines the quantitative information for the amount of the most toxic metabolite. The maximum dose of the parent chemical is estimated which will not result in the generation of toxic metabolites sufficient to cause harmful effects. This quantitative approach permits a calculation of the margin of exposure, is noteworthy for industrial assessment purposes.

Single-Dose Oral Toxicity Study of Chloroform Extract of Kaffir Lime (Citrus hystrix DC.) Leaves in Wistar Rats (Rattus norvegicus Berkenhout, 1769)

Leaves of kaffir lime (Citrus hystrix) are commonly used as a seasoning in various Indonesian and Southeast Asian dishes. Phytochemical studies reported various secondary metabolites that possess medicinal properties. Before exploring their potential as therapeutic agent, a series of toxicity studies must be conducted to assess the toxicity and safety levels. This research aimed to study the single-dose acute oral toxicity of chloroform extract of kaffir lime leaves (CECHL) in female Wistar rats (Rattus norvegicus) as experimental animals. The procedure followed OECD Test Guideline No.420 with the dose 2000 mg/kg bw for 14 days (Sighting study). Parameters consisted of mortality, clinical signs of sublethal effect based on changes in general appearance and daily activity/behavior, hematological profile, and blood clinical biochemistry. Neither mortality nor sublethal effects were found during the experiment. All blood parameter values (erythrocytes, leukocytes, thrombocytes, ALT, AST, creatinine, BUN, glucose, cholesterol, and triglycerides) were within reference interval, indicating that CECHL is not harmful to normal physiology. In conclusion, single-dose oral administration of CECHL is safe, no-observed-adverse-effect-level (NOAEL) at dose 2000 mg/kg bw or included in Category 5 based on the Globally Harmonized System of Classification and Labeling of Chemicals (GHS).

“GC-MS profiling, sub-acute toxicity study and total phenolic and flavonoid content analysis of methanolic leaf extract of Schima wallichii (D.C.) Korth-a traditional antidiabetic medicinal plant”

Ethnopharmacological relevanceSchima wallichii (D.C.) Korth is traditionally used in Manipur, India for treatment of diabetes and hypertension. However, there is no data reported regarding safety profile of this medicinal plant upon repeated per oral administration over a period of time. Aim of the studyIn the current study phytochemical profile, toxicological profile and total phenolic and flavonoid compound content of Schima wallichii leaves extract were evaluated. Materials and methodsGas chromatography coupled to mass spectrometry was performed for chemical profiling by using Gas Chromatography-Mass Spectrometry/Mass Spectrometry (GC-MS/MS), Shimadzu, TQ8040 system. A 28 days sub-acute toxicity study was carried out using albino Wistar rats by administering 3 different doses (200, 400 and 800 mg/kg body weight per oral) of methanol leaves extract. Changes in body weights were recorded weekly. Serum biochemical parameters were estimated as well as blood-cell count was done to check the effect of extract on haematopoietic system. Histopathology of vital organs viz. kidney, heart, brain, liver was performed to find any pathological indications. Since, liver is main the site for xenobiotic metabolism, estimation of the level of glutathione, catalase and lipid peroxidation were done. Further, total phenolic and flavonoid compound content estimation was performed for the leaves extract. ResultsGC-MS revealed 14 major compounds with area percentage >1% of which quinic acid, n-Hexadecanoic acid, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, Octatriacontyl trifluoroacetate, are three major compounds. No mortality was observed after the treatment with extract. Blood-cell count and biochemical parameters didn't show significant deviation as compared to control group. Histopathology study of vital organs viz. (liver, kidney, heart and brain) showed normal cellular construction comparing to control group. There was no sign of membrane lipid peroxidation, depletion of catalase level and glutathione level in liver. The result demonstrates that NOAEL (no-observed-adverse-effect levels) in the sub-acute toxicity was above 800 mg/kg. The leaves extract showed significant total phenol and flavonoid content. ConclusionThe present study revealed that Schima wallichii possessed important bioactive compounds with therapeutic values. The plant was safe for consumption after repeated high doses administration in rats and possesses significant amount of total phenol and flavonoid content.

Comparing the effects and potencies of perchlorate and nitrate on amphibian metamorphosis using a modified amphibian metamorphosis assay (AMA).

A modified amphibian metamorphosis assay was performed in which Nieuwkoop and Faber (NF) stage 47 Xenopus laevis larvae were exposed to different concentrations of either perchlorate (ClO4 -) or nitrate (NO3 -) for 32 days. Larvae were exposed to 0.0 (control), 5, 25, 125, 625, and 3125 μg/L ClO4 -, or 0 (control), 23, 71, 217, 660, and 2000 mg/L NO3 -. The primary endpoints were survival, hind limb length (HLL), forelimb emergence and development, developmental stage (including time to NF stage 62 [MT62]), thyroid histopathology, wet weight, and snout-vent length (SVL). Developmental delay as evidenced by altered stage distribution and increased MT62, a higher degree of thyroid follicular cell hypertrophy, and an increase in the prevalence of follicular cell hyperplasia was observed at concentrations ≥125 μg/L ClO4 -. The no observed effect concentration (NOEC) for developmental endpoints was 25.0μg/L ClO4 - and the NOEC for growth endpoints was 3125 μg/L ClO4 -. Exposure to nitrate did not adversely affect MT62, but a decreasing trend in stage distribution and median developmental stage at ≥217 mg/L NO3 - was observed. No histopathologic effects associated with nitrate exposure were observed. An increasing trend in SVL-normalized HLL was observed at 2000 mg/L NO3 -. Nitrate did not alter larval growth. The NOEC for developmental endpoints was 71 mg/L NO3 -, and 2000 mg/L NO3 - for growth endpoints. The present study provided additional evidence that the effects and potency of nitrate and perchlorate on metamorphosis and growth in X.laevis are considerably different.

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.

Evaluation on the traditional safe use of Kochiae Fructus oriented by antioxidant properties and oral safety of its ethanolic extract

Kochiae Fructus (KF) is a traditional Chinese medicine, which has been used to delay aging and treat inflammation, such as rubella, eczema, cutaneous pruritus, etc. In order to fully understand the traditional medicinal value of KF, we evaluated the antioxidant properties and oral safety of its ethanolic extract. Considering flavonoids and phenolics in medicinal plants generally have strong antioxidant activity, we firstly detected the total flavonoids and phenolics contents of KFEE and its fractions. Secondly, we evaluated the antioxidant activities of KFEE and its fractions. Finally, we evaluated the oral safety of KFEE by the acute and 28-day subacute toxicities. The n-butanol fraction (ENBF) possessed the highest phenolics and flavonoids with values of 77.30 ± 3.17 mg gallic acid equivalents/g and 228.81 ± 7.56 mg rutin equivalents/g, respectively. The results of antioxidant tests showed that ENBF possessed potent antioxidant ability. Among them, the high antioxidation capacity observed in ENBF could be attributed to its rich content of flavonoids and phenolics. The results of toxicological studies showed that the LD50 value of KFEE was 6000 mg/kg BW, and the no observed adverse effect level (NOAEL) of KFEE was 600 mg/kg BW. According to the standards of the American Academy of Sciences for the classification of toxic substances, KFEE can be classified as practically non-toxic substance, which provided valuable evidence for the oral safety of KF as a natural aging delay medicine.

Repeated-dose toxicity and toxicokinetic study of isobutylparaben in rats subcutaneously treated for 13weeks.

Parabens have historically served as antimicrobial preservatives in a range of consumables such as food, beverages, medications, and personal care products due to their broad-spectrum antibacterial and antifungal properties. Traditionally, these compounds were believed to exhibit low toxicity, causing minimal irritation, and possessing limited sensitization potential. However, recent evidence suggests that parabens might function as endocrine-disrupting chemicals (EDCs). Consequently, extensive research is underway to elucidate potential human health implications arising from exposure to these substances. Among these parabens, particular concerns have been raised regarding the potential adverse effects of iso-butylparaben (IBP). Studies have specifically highlighted its potential for inducing hormonal disruption, significant ocular damage, and allergic skin reactions. This study aimed to evaluate the prolonged systemic toxicity, semen quality, and estrus cycle in relation to endocrine disruption endpoints, alongside assessing the toxicokinetic behavior of IBP in Sprague-Dawley rats following a 13-week repeated subcutaneous administration. The rats were administered either the vehicle (4% Tween 80) or IBP at dosage levels of 2, 10, and 50mg/kg/day for 13weeks. Blood collection for toxicokinetic study was conducted on three specified days: day 1 (1st), day 30 (2nd), and day 91 (3rd). Systemic toxicity assessment and potential endocrine effects were based on various parameters including mortality rates, clinical signs, body weights, food and water consumption, ophthalmological findings, urinalysis, hematological and clinical biochemistry tests, organ weights, necropsy and histopathological findings, estrus cycle regularity, semen quality, and toxicokinetic behavior. The findings revealed that IBP induced local irritation at the injection site in males at doses ≥ 10mg/kg/day and in females at 50mg/kg/day; however, systemic toxicity was not observed. Consequently, the no-observed-adverse-effect level (NOAEL) for IBP was determined to be 50mg/kg/day in rats of both sexes, indicating no impact on the endocrine system. The toxicokinetics of IBP exhibited dose-dependent systemic exposure, reaching a maximum dose of 50mg/kg/day, and repeated administration over 13weeks showed no signs of accumulation.

Safety assessment of mixtures of 1,9-nonanediamine (NMDA) and 2-methyl-1,8-octanediamine (MODA), for use in food contact materials.

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of mixtures of 1,9-nonanediamine (NMDA) and 2-methyl-1,8-octanediamine (MODA) when used to produce polyamide food contact materials for contact with all food types for long-term storage at room temperature and below, including heating up to 121°C for up to 2 h. The polyamide material is also intended to be used for repeated use up to 121°C with short contact (up to 30 min). The polymer typically contains ■■■■■ of a low molecular weight fraction (LMWF, < 1000 Da). The specific migration was measured with polyamide samples in a set of migration tests with 3% acetic acid and 10% ethanol. NMDA and MODA were not detected at ■■■■■, respectively. The specific migration of the LMWF consisting of NMDA/MODA-related species was up to ■■■■■. The overall migration in olive oil was below the detection limit (3 mg/dm2). The most abundant migrating LMWF oligomers were identified. Toxicological studies were performed with NMDA, MODA and with polyamide formulations enriched in the LMWF. The results of genotoxicity assays did not raise a concern. From a repeated-dose oral 90-day toxicity study in rats, the Panel identified a no observed adverse effect level (NOAEL) of 1000 mg/kg body weight per day for the migrating LMWF. The CEP Panel concluded that NMDA/MODA mixtures do not raise a safety concern for the consumer when used as comonomer with terephthalic acid to manufacture polyamide articles intended for contact with all food types, except for infant formula and human milk, if the migration of NMDA and MODA does not exceed 0.05 mg/kg food (as a sum of the two substances) and if the migration of the LMWF consisting of NMDA/MODA-related species does not exceed 5 mg/kg food.

Chronic dietary exposure to a glyphosate-based herbicide alters ovarian functions in young female broilers

Glyphosate (GLY)-based herbicide (GBH) formulations are widely used pesticides in agriculture. The European Union recently decided to extend the use of GLY in Europe until 2034. Previously, we showed that chronic dietary GBH exposure in adult hens resulted in a reversible increase in early mortality in chicken embryos. In this present study, we investigated the GBH effects on metabolism and ovarian functions by using a transcriptomic approach in vivo in young female broilers and in vitro in ovarian explant cultures. We exposed 11-day-old female broilers to 13 mg GLY equivalent/kg body weight/day (GBH13, n = 20), 34 mg GLY equivalent/kg body weight/day (GBH34, n = 20), or a standard diet (control [CT], n = 20) for 25 days. These two GBH concentrations correspond to approximatively one eighth and one third of the no observed adverse effect level (NOAEL) as defined by European Food Safety Authority in birds. During this period, we evaluated body weight, fattening, food intake, and the weight of organs (including the ovaries). Chronic dietary GBH exposure dose dependently reduced food intake, body weight, and fattening, but increased oxidative stress and relative ovary weight. We analyzed the ovarian gene expression profile in CT, GBH13, and GBH34 broilers with RNA sequencing and showed that differentially expressed genes are mainly enriched in pathways related to cholesterol metabolism, steroidogenesis, and RNA processing. With quantitative polymerase chain reaction and western blotting, we confirmed that GBH decreased ovarian STAR and CYP19A1 messenger RNA and protein expression, respectively. Furthermore, we confirmed that GBH altered steroid production in ovarian explants. We have identified potential regulatory networks associated with GBH. These data provide valuable support for understanding the ovarian transcriptional regulatory mechanism of GBH in growing broilers.

Ecological impact of pharmaceutical pollutants and options of river health improvements - A risk analysis-based approach

Pharmaceuticals are one of the emerging pollutants (EPs) in river waters across the world. Due to their toxic effects on aquatic organisms, they have drawn the global attention of the scientific community concerned with river ecosystems. This paper reviews the existing occurrence data for various pharmaceutical pollutants (PPs) reported in river waters in some part of the world and their ecological impacts. Using algae, macroinvertebrates (MI), and fish as biotic indicator groups in water to reflect river health conditions, an attempt has been made to assess the ecological risk due to the presence of PPs in the water environment.After ascertaining the predicted no-effect concentration (PNEC) of PPs for selected groups of aquatic organisms, the risk quotient (RQ) is estimated based on their measured environmental concentration (MEC). When MEC > PNEC and RQ > 1 for any of the biotic indicator, ecologically it is ‘high risk’ condition. The determination of PNEC uses a minimum assessment factor (AF) of 10 due to uncertainty in data over the no observed effect level (NOEL) or lowest observed effect level (LOEL). Accordingly, MEC 10 times higher than PNEC, (RQ = 10) represents a threshold risk concentration (RCT) beyond which adverse effects may start showing observable manifestations. In the present study, a new classification system of ‘high risk’ conditions for RQ = 1–10 has been proposed, starting from ‘moderately high’ to ‘severely high’. For RQ > 10, the ecological condition of the river is considered ‘impaired’.For river health assessment, in the present study, the whole range of physico-chemical characteristics of river water quality has been divided into three groups based on their ease of measurement and frequency of monitoring. Dissolved oxygen related parameters (DORPs), nutrients (NTs), and EPs. PPs represent EPs in this study. A framework for calculating separate indicator group score (IGS) and the overall river health index (RHI) has been developed to predict indicator group condition (IGC) and river health condition (RHC), respectively. Color-coded hexagonal pictorial forms representing IGC and RHC provide a direct visible perception of the existing aquatic environment and a scientific basis for prioritization of corrective measures in terms of treatment technology selection for river health improvements.The analyses indicate that many rivers across the world are under ‘high risk’ conditions due to PPs having MEC > PNEC and RQ > 1. Up to RCT, (where RQ = 10), the ‘high risk’ condition varies from ‘moderately high’ to ‘severely high’. In many instances, RQ is found much more higher than 10, indicating that the ecological condition of river may be considered as ‘impaired’. Algae is the most frequently affected group of biotic indicators, followed by MI and fish.A review of treatment methods for selection of appropriate technology to reduce the pollution load, especially PPs from the wastewater streams has been summarized. It appears that constructed wetlands (CWs) are at present the most suitable nature-based solutions, particularly for the developing economies of the world, to reduce the concentrations of PPs within limits to minimize the ecological impacts of pharmaceutical compounds on biotic indicators and restore the river health condition. Some suggestive design guidelines for the CWs have also been presented to initiate the process.

In vivo tebuconazole administration impairs heart electrical function and facilitates the occurrence of dobutamine-induced arrhythmias: involvement of reactive oxygen species

Tebuconazole (TEB), a widely used pesticide in agriculture to combat fungal infections, is commonly detected in global food, potable water, groundwater, and human urine samples. Despite its known in vivo toxicity, its impact on heart function remains unclear. In a 28-day study on male Wistar rats (approximately 100 g), administering 10 mg/kg/day TEB or a vehicle (control) revealed no effect on body weight gain or heart weight, but an increase in the infarct area in TEB-treated animals. Notably, TEB induced time-dependent changes in in vivo electrocardiograms, particularly prolonging the QT interval after 28 days of administration. Isolated left ventricular cardiomyocytes exposed to TEB exhibited lengthened action potentials and reduced transient outward potassium current. TEB also increased reactive oxygen species (ROS) production in these cardiomyocytes, a phenomenon reversed by N-acetylcysteine (NAC). Furthermore, TEB-treated animals, when subjected to an in vivo dobutamine (Dob) and caffeine (Caf) challenge, displayed heightened susceptibility to severe arrhythmias, a phenotype prevented by NAC. In conclusion, TEB at the no observed adverse effect level (NOAEL) dose adversely affects heart electrical function, increases arrhythmic susceptibility, partially through ROS overproduction, and this phenotype is reversible by scavenging ROS with NAC.

Safety of Repeated Administration of Xenogeneic Human Apoptotic State (Allocetra-OTS) in Sprague Dawley Rats.

Apoptotic cells possess immunomodulatory effects that can be utilized to treat imbalanced immune conditions. Information on the preclinical safety of such treatment is sparse. In this study, the safety of apoptotic cells (Allocetra-OTS) was assessed in a GLP toxicological study on Sprague Dawley rats. Three doses of Allocetra-OTS or vehicle were administered intravenously (IV) for 3 consecutive days. Animals in the main study were sacrificed on day 4, while animals from the recovery groups were kept for 14 or 28 days. Allocetra-OTS was well tolerated, and no adverse effects were observed in terms of body weight, clinical signs, food consumption, or ophthalmologic observation. Thus, the No Observed Adverse Effect Level (NOAEL) dose was determined as the highest dose administered. An observed elevation in immune cells was suspected to be due to Allocetra-OTS, similarly to other clinical chemistry parameters; however, it was resolved in the recovery phases. Splenomegaly and dose-related extramedullary hematopoiesis (EMH) in the red pulp were observed, with no adverse events, and were considered to be a normal and expected reaction following the IV administration of cell-based therapies. In conclusion, under the conditions of this study, Allocetra-OTS was concluded to be safe, further supporting its potential candidacy for clinical studies.

Clinico-hematological Effects of Nanosilver Administration in Wistar Rats

This study evaluated the haematological effects of the oral administration of silver nanoparticle in Wistar rats. A total of 35 rats, six weeks of aged, both male and female, were randomly divided into two groups. Group 1 was kept as control and comprised of 20 rats. Group II comprised of 15 rats and the rats were orally administered silver nanoparticle mixed in distilled water at no-observed-adverse-effect level (NOAEL) dose rate of 30 mg/kg body weight/day daily for 90 days of experiment. Blood was collected from 5 rats from each group at 0, 30th, 60th and 90th days post-treatment. A traditional Manual method was used to measure Hematological parameters and data analyzed by one-way ANOVA (post hoc Dunnett's test). The hematological parameters studied were significantly altered in treatment group as compared to control animals. Morphology of erythrocytes indicates normocytic hypochromic anaemia. Our results indicated that the silver nanoparticles have adverse effects on general clinical condition and hematological parameters of rats at NOAEL dose.

Preclinical and translational pharmacology of afucosylated anti-CCR8 antibody for depletion of tumour-infiltrating regulatory T cells.

RO7502175 is an afucosylated antibody designed to eliminate C-C motif chemokine receptor 8 (CCR8)+ Treg cells in the tumour microenvironment through enhanced antibody-dependent cellular cytotoxicity (ADCC). We report findings from preclinical studies characterizing pharmacology, pharmacokinetics (PK)/pharmacodynamics (PD) and safety profile of RO7502175 and discuss the translational PK/PD approach used to inform first-in-human (FiH) dosing strategy and clinical development in solid tumour indications. RO7502175 demonstrated selective ADCC against human CCR8+ Treg cells from dissociated tumours in vitro. In cynomolgus monkeys, RO7502175 exhibited a biphasic concentration-time profile consistent with immunoglobulin G1 (IgG1) antibodies, reduced CCR8+ Treg cells in the blood, induced minimal and transient cytokine secretion, and was well tolerated with a no-observed-adverse-effect level (NOAEL) of 100 mg·kg-1 . Moreover, RO7502175 caused minimal cytokine release from peripheral blood mononuclear cells (PBMCs) in vitro. A quantitative model was developed to capture surrogate anti-murine CCR8 antibody PK/PD and tumour dynamics in mice and RO7502175 PK/PD in cynomolgus monkeys. Subsequently, the model was used to project RO7502175 human PK and receptor occupancy (RO) in patients. Because traditional approaches resulted in a low FiH dose for this molecule, even with its superior preclinical safety profile, an integrated approach based on the totality of preclinical data and modelling insights was used for starting dose selection. This work demonstrates a translational research strategy for collecting and utilizing relevant nonclinical data, developing a mechanistic PK/PD model and using a comprehensive approach to inform clinical study design for RO7502175.

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.

Safety evaluation of vitamin K2 (menaquinone-7) via toxicological tests

This study aims to evaluate the safety of MK-7 produced by fermentation process using a Bacillus subtilis var. natto strain for human ingestion via acute oral toxicity, repeated dose 90-day oral toxicity, 28-day recovery test, and genotoxicity tests. The acute oral toxicity test results indicated that all subjects survived at the dose of 5000 mg/kg with no toxic effects. For the repeated dose 90-day oral toxicity test, MK-7 was administered to rats at 500, 1500, and 4500 mg/kg for 90 d. No abnormal findings were detected in clinical observations or in clinical pathological and histopathological examinations. The no-observed-adverse-effect level(NOAEL) was determined to be 4500 mg/kg/d, the maximum dose tested. For the evaluation of genotoxicity, reverse mutation, chromosomal aberration, and micronucleus tests were performed. In the reversion mutation test, vitamin K2 did not induce reversion in bacterial strains, and no chromosomal abnormality was observed in the chromosomal abnormality test using Chinese hamster lung cells. In the micronucleus test, micronuclei were not induced using ICR mouse bone marrow cells. All the toxicity test results suggest that vitamin K2 produced by fermentation processes using Bacillus subtilis var. natto induced no toxicological changes under the experimental conditions.

Calculations of the Radiation Dose for the Maximum Hormesis Effect

To date, the radiation-adaptive response has been reported as a low-dose-related phenomenon and has been associated with radiation hormesis. Well-known cancers are caused by non-radiation active reactants, in addition to radiation. A model of suppression for radiation-specific cancers was previously reported, but the model did not target radiation-nonspecific cancers. In this paper, we describe kinetic models of radiation-induced suppressors for general radiation non-specific cancers, estimating the dose M that induces the maximum hormesis effect while satisfying the condition that the risk is approximately proportional to a dose above NOAEL (No Observed Adverse Effect Level). The radiation hormesis effect is maximal when the rate constant for generation of a risk-reducing factor is the same as the rate constant for its decomposition. When the two rate constants are different, the dose M at which the radiation hormesis effect is maximized depends on both rate constants, but the dose M increases as the two rate constants approach each other, reaching a maximum dose. The theory proposed in this paper can only explain existing experiments with extremely short error bar lengths. This theory may lead to the discovery of unknown risk-reducing factor at low doses and the development of risk-reducing methods in the future.

Exposure to the environmental pollutant chlorpyrifos induces hepatic toxicity through activation of the JAK/STAT and MAPK pathways

Chlorpyrifos (CHP) is an inexpensive highly effective organophosphate insecticide used worldwide. The unguided and excessive use of CHP by farmers has led to its significant accumulation in crops as well as contamination of water sources, causing health problems for humans and animals. Therefore, this study evaluated the toxicological effects of exposure to the environmental pollutant CHP at low, medium, and high (2.5, 5, and 10 mg·kg−1 BW) levels on rat liver by examining antioxidant levels, inflammation, and apoptosis based on the no observed adverse effect levels (NOAEL) (1 mg·kg−1 BW) and the CHP dose that does not cause any visual symptoms (5 mg·kg−1 BW). Furthermore, the involvement of the JAK/STAT and MAPK pathways in CHP-induced toxic effects was identified. The relationship between the expression levels of key proteins (p-JAK/JAK, p-STAT/STAT, p-JNK/JNK, p-P38/P38, and p-ERK/ERK) in the pathways and changes in the expression of markers associated with inflammation [inflammatory factors (IL-1β, IL-6, IL-10, TNF-α), chemokines (GCLC and GCLM), and inflammatory signaling pathways (NF-кB, TLR2, TLR4, NLRP3, ASC, MyD88, IFN-γ, and iNOS)] and apoptosis [Bad, Bax, Bcl-2, Caspase3, Caspase9, and the cleavage substrate of Caspase PARP1] were also determined. The results suggest that CHP exposure disrupts liver function and activates the JAK/STAT and MAPK pathways via oxidative stress, exacerbating inflammation and apoptosis. Meanwhile, the JAK/STAT and MAPK pathways are involved in CHP-induced hepatotoxicity. These findings provide a novel direction for effective prevention and amelioration of health problems caused by CHP abuse in agriculture and households.