Human Dose Research Articles

Occurrence and human exposure risk of antibiotic resistance genes in tillage soils of dryland regions: A case study of northern Ningxia Plain, China

Agricultural soils are important source and sink of antibiotic resistance genes (ARGs). However, little is known about the fate of ARGs in dryland soils, while its human exposure risks were seriously overlooked. Taking the northern Ningxia Plain as a case, this study explored the occurrence of ARGs and its relationship with mobile genetic elements (MGEs), pathogens, and environmental factors. Furthermore, the concentrations of airborne ARGs by soil wind erosion and the human exposure doses of soil ARGs were evaluated. The results showed the abundances of different regions ranged from 4.0 × 105 to 1.6 × 106 copies/g. Soil ARGs are driven by MGEs, but multiply impacted by soil properties, nutrition, and bacterial community. Vibrio metschnikovii, Acinetobacter schindleri, and Serratia marcescens are potential pathogenic hosts for ARGs. Further exploration revealed the concentration of ARGs loaded in dust by soil wind erosion reached more than 105 copies/m3, which were even higher than those found in sewage treatment plants and hospitals. Skin contact is the primary route of ARGs exposure, with a maximum dose of 24071.33 copies/kg/d, which is largely attributed to ARGs loaded in dust. This study bridged the gap on ARGs in dryland soils, and provided reference for human exposure risk assessment of soil ARGs.

In Utero and Lactational Exposure to an Environmentally Relevant Mixture of Phthalates Alters Hypothalamic Gene Expression and Sexual Preference in Rats.

Several phthalates, mainly used as plasticizers, are known for their adverse effects on the male genital system. Previously, we demonstrated that an environmentally relevant mixture of six antiandrogenic phthalates (PMix), derived from a biomonitoring study in pregnant Brazilian women, was able to disrupt the reproductive development in male rats. Experimental groups (control, 0.1, 0.5, and 500 mg PMix/kg/day) were established starting from the extrapolated human dose (0.1 mg/kg/day), followed by doses 5 times and 5000 times higher. Pregnant rats received daily oral gavage administration of either vehicle (control) or PMix from gestational day 13 to postnatal day 10. Here, we examined male and female offspring regarding changes in gene expression of key reproductive factors in the hypothalamus and pituitary gland at adulthood and conducted a battery of behavioral tests in males, including partner preference, sexual behavior, and male attractiveness tests. PMix induced some changes in mating-related behavior in males, as demonstrated by the absence of preference for females against males and a higher number of penetrations up to ejaculation in the 0.5 dose group. PMix decreased Esr2 expression in the male hypothalamus across all three doses, and in females at mid and high doses in both the hypothalamus and pituitary. In male hypothalamus, we also observed decreased Kiss1 transcripts in these groups and a reduction in AR at the 0.5 dose group. In summary, our results provide further evidence that phthalates in a mixture, even at low doses, may exert cumulative effects on the structures underlying sexual behavior, which seems to be more sensitive than reproductive endpoints for the same experimental design.

Luteinizing hormone supplementation with human menopausal gonadotropin versus low dose human chorionic gonadotropin during ovarian stimulation does not affect live birth rates after fresh and frozen embryo transfer.

Luteinizing hormone (LH) plays an important role in ovarian follicle maturation. Human menopausal gonadotropin (hMG) or low dose human chorionic gonadotropin (hCG) can provide LH supplementation during in vitro fertilization (IVF) ovarian stimulation, though studies directly comparing their impact on IVF outcomes are limited. The aim of the study was to determine whether LH supplementation with hMG versus low dose hCG during IVF stimulation affects live birth rate. Fresh and frozen embryo transfers (ET) from 2017 to 2021 after standard long or antagonist protocols supplemented with hMG (75-250 IU) or low dose hCG (50-100 IU) during stimulation cycles in our academic center were included. Statistical analysis was performed with T-tests, Mann-Whitney U tests, Chi-square, and multiple linear and logistic regression. Four hundred and sixty eight unique stimulation cycles resulting in 213 fresh and 412 frozen embryo transfers were analyzed. There was a lower mature oocyte yield (10.9 vs. 11.8, p = 0.044) but similar high-quality blastocyst yield (3.6 vs. 3.9, p = 0.11) for hMG vs low dose hCG. Live birth rates per transfer were comparable for fresh (42% vs. 49%, p = 0.24) and frozen (46% vs. 53%, p = 0.45) embryo transfers. Multiple logistic regressions showed no association between supplemental gonadotropin and live birth for both fresh and frozen embryo transfers. Fresh and frozen IVF-ET pregnancy outcomes were comparable after hMG versus low dose hCG supplementation, suggesting flexibility in supplemental LH dosing regimens that may address patient or physician preference or cost concerns.

BSP – Computer code for evaluating protection against bremsstrahlung radiation from extended beta radiation sources

For a long time, radiation safety specialists have been aware of computer codes designed to calculate human dose exposure from beta or gamma radiation. However, these products have a major drawback: they do not consider the radiation fields generated by extended beta radiation sources due to bremsstrahlung. Existing solutions are either not widely available or use outdated nuclear-physical constants and methods for calculating dosimetric characteristics. A computer code was developed specifically for calculating shielding against bremsstrahlung. It allows to estimate effective, equivalent, exposure dose rate, ambient dose equivalent, and air kerma rate from bremsstrahlung. It utilizes the ANS/ANSI 6.4.3 materials data and the last dose conversion factors from ICRP 116.

Distributions of polycyclic aromatic hydrocarbons in ambient air samples from Hanoi urban areas, Vietnam, and its implications for inhalation exposure.

Sixteen PAHs in ambient air samples collected from residential and roadside areas in the Hanoi metropolitan were investigated. Total PAH concentrations in the ambient air samples ranged from 45.0 to 451ng/m3. Among PAHs, phenanthrene was found at the most abundant and highest levels. The distributions of PAHs in the ambient air collected in the dry season were on average 26% higher than in the wet season. The PAH concentrations in the air samples collected from the traffic areas were significantly higher (about 2.7 times) than those in the residential areas, indicating that these chemicals originated from motor vehicles. According to vertical, the PAH concentrations found in the ambient air samples collected from the ground floor were significantly higher than on the upper level, however, there was not much difference when going higher (from 24m (8th floor) to 111m (37th floor)). The human exposure doses were estimated for two age groups (adults and children) based on the measured PAH concentrations, the inhalation rates, and body weights. The estimated exposure doses to PAHs through inhalation for adults/children were 1.13/2.86 (ng/kg-bw/d) (residential areas) and 3.24/8.18 (ng/kg-bw/d) (traffic areas), respectively. The average lifetime excess cancer risk (ECR) from inhalation exposure to PAHs was 3.0 × 10-4 at the traffic areas and 1.4 × 10-4 at the residential areas. These estimated exposure doses were above the acceptable level of the California Environmental Protection Agency (CalEPA) Office of Environmental Health Hazard Assessment (1*10-6).

Chemically Resolved Respiratory Deposition of Ultrafine Particles Characterized by Number Concentration in the Urban Atmosphere.

Ultrafine particles (UFPs) dominate the atmospheric particles in number concentration, impacting human health and climate change. However, existing studies primarily rely on mass-based approaches, leading to a restricted understanding of the number-based and chemically resolved health effects of atmospheric UFPs. In this study, we utilized a high-mass-resolution single-particle aerosol mass spectrometer to investigate the online chemical composition and number size distribution of ultrafine, fine, and coarse particles during the summertime in urban Shenzhen, China. Human respiratory deposition dose assessments of particles with varying chemical compositions were further conducted by a respiratory deposition model. The results showed that during our observation, particles containing elemental carbon (EC) were the dominant components in UFPs (0.05-0.1 μm). Compared to fine and coarse particles, UFPs can deposit more deeply into the respiratory tract with a daily dose of ∼2.08 ± 0.67 billion particles. Among the deposited UFPs, EC-cluster particles constituted ∼85.7% in number fraction, accounting for a daily number dose of ∼1.78 billion particles, which poses a greater impact on human health. Simultaneously, we found discrepancies in the chemically resolved particle depositions among number-, surface area-, and mass-based approaches, emphasizing the importance of an appropriate metric for particle health-risk evaluation.

Proapoptotic Bcl-2 inhibitor as host directed therapy for pulmonary tuberculosis.

Mycobacterium tuberculosis establishes within host cells by inducing anti-apoptotic Bcl-2 family proteins, triggering necrosis, inflammation, and fibrosis. Here, we demonstrate that navitoclax, an orally bioavailable, small-molecule Bcl-2 inhibitor, significantly improves pulmonary tuberculosis (TB) treatments as a host-directed therapy. Addition of navitoclax to standard TB treatments at human equipotent dosing in mouse models of TB, inhibits Bcl-2 expression, leading to improved bacterial clearance, reduced tissue damage / fibrosis and decreased extrapulmonary bacterial dissemination. Using immunohistochemistry and flow cytometry, we show that navitoclax induces apoptosis in several immune cells, including CD68 + and CD11b + cells. Finally, positron emission tomography (PET) in live animals using novel, clinically translatable biomarkers for apoptosis ( 18 F-ICMT-11) and fibrosis ( 18 F-FAPI-74) demonstrates that navitoclax significantly increases apoptosis and reduces fibrosis in pulmonary tissues, which are confirmed using post-mortem studies. Our studies suggest that proapoptotic drugs such as navitoclax can improve pulmonary TB treatments, and should be evaluated in clinical trials.

Human intrusion dose assessment for the safe disposal of radioactive spent resin mixed waste at disposal facilities

This study explores the feasibility of safely disposing of spent resin mixed waste from which pure beta emitters(14C, 3H) have been removed 95 % at near-surface disposal facilities and evaluates the radiation dose to the public in the event of human intrusion after the management period of the disposal site. The decommissioning of Wolsong Unit 1, Korea's first commercial heavy water reactor, marks a critical juncture in the field of nuclear energy, highlighting the imperative for advancements in the methodologies of decommissioning, decontamination, and stewardship of mixed spent resin radioactive waste. To this end, six human intrusion scenarios are examined, and a cross-validation is performed using GENII and RESRAD-ONSITE simulation codes to confirm that the public dose criterion of 1 mSv/y is not exceeded under any of the scenarios. This result suggests that the safe disposal of waste from which beta radionuclides have been removed is possible, carrying significant implications for waste management and environmental protection. Such assessments provide scientific evidence for establishing waste disposal strategies and can serve as foundational data for the sustainable utilization of nuclear energy.

P10-11 Effects of a mixture of PCB 138, 153 and 180 on early embryo development in vitro, using human relevant doses

P10-11 Effects of a mixture of PCB 138, 153 and 180 on early embryo development in vitro, using human relevant doses

Abstract P191: Progesterone Supplementation Ameliorates the Maternal Syndrome of Preeclampsia in the Dahl Salt-Sensitive Rats

Introduction: Preeclampsia (PreE) is characterized by new onset hypertension after 20 weeks of gestation. PreE is associated with activated CD4+ T cells, inflammation, autoantibodies to angiotensin II type 1 receptor (AT1-AA) and hypertension. To date, the best treatment remains early delivery of the feto-placental unit. Hypothesis: This study was designed to test the hypothesis that progesterone, in the form of 17-hydroxyprogesterone caproate (17-OHPC), reduces inflammation and blood pressure in the Dahl Salt-Sensitive (Dahl S) rat model of PreE. Methods: A subset of pregnant Sprague-Dawley (SD) and Dahl S rats were injected with 17-OHPC (3.32mg/kg, human dose equivalent) or vehicle (saline) at day 15 (GD15) of gestation. On GD 18, Uterine Artery Resistance Index (UARI) was measured by Doppler Ultrasound and carotid catheters were inserted for mean arterial blood pressure (MAP) measurement on GD19. Circulating and placental populations of CD4+ T cells were quantified by flow cytometry. TNF-alpha and IL-6 were measured by ELISA and AT1-AA were quantified by the chronotropic responses to angiotensin II type 1 receptor-mediated stimulation of cultured neonatal rat cardiomyocytes. Results are reported as means ± standard error means (SEM) and statistically significant when p < 0.05. Results: MAP was 105±5 mmHg in SD+ vehicle rats (n=6), 104±4 in SD+17-OHPC rats (n=6), 136±3 in Dahl S+ saline rats (p <0.05, n=11), which improved to 125±4 in DS+17-OHPC rats (p <0.05, n=7). Pup and Placenta weights were 2.1± 0.1, 0.6 ± 0.1 g in SD+ vehicle rats and reduced to 1.4±0.1 (p<0.05), 0.5±0.1 g in Dahl S +vehicle. UARI was 0.5 ±0.1 in SD+ vehicle rats (n=6) and 0.5 ±0.1 in in SD+17-OHPC (n=6), 0.7±0.1 in Dahl S+ vehicle rats (n=6, p<0.05), which reduced to 0.5±0.1 in Dahl S+17-OHPC (n=7, p<0.05). TNF-alpha and IL-6 levels (n=4-5/group) were 3.0±1.0, 45±11 pg/mL in SD+ vehicle rats, 11.0±1.2, 78±21 in Dahl S+ vehicle rats, which reduced to 4.1±1.6 (p<0.05), 62±12 in Dahl S+17-OHPC. Circulating and placental CD4+ T cells were 9.3±3.7 %, 6.4± 1.6 % gate in SD+ vehicle rats (n=4), 38.9 ±2.9, 33.1±4.3 % gate Dahl S+ Saline rats (n=6), which significantly reduced to 26.3 ± 0.1 %, 3.4±1.2 % gate in DahlS+17-OHPC. AT1-AA were -1 ± 2 ΔBPM (beats per minute) in SD+ vehicle rats, 4 ± 1 in Dahl S+ Saline rats and -0.6±2 Dahl S+17-OHPC rats (n=5, p<0.05). Conclusion: Our findings demonstrate that 17-OHPC ameliorates the maternal syndrome in the Dahl Salt-Sensitive rat model of PreE.

Beyond MABEL: An Integrative Approach to First in Human Dose Selection of Immunomodulators by the Health and Environmental Sciences Institute (HESI) Immuno-Safety Technical Committee (ITC).

Administration of a new drug candidate in a first-in-human (FIH) clinical trial is a particularly challenging phase in drug development and is especially true for immunomodulators, which are a diverse and complex class of drugs with a broad range of mechanisms of action and associated safety risks. Risk is generally greater for immunostimulators, in which safety concerns are associated with acute toxicity, compared to immunosuppressors, where the risks are related to chronic effects. Current methodologies for FIH dose selection for immunostimulators are focused primarily on identifying the minimum anticipated biological effect level (MABEL), which has often resulted in sub-therapeutic doses, leading to long and costly escalation phases. The Health and Environmental Sciences Institute (HESI) - Immuno-Safety Technical Committee (ITC) organized a project to address this issue through two complementary approaches: (i) an industry survey on FIH dose selection strategies and (ii) detailed case studies for immunomodulators in oncology and non-oncology indications. Key messages from the industry survey responses highlighted a preference toward more dynamic PK/PD approaches as in vitro assays are seemingly not representative of true physiological conditions for immunomodulators. These principles are highlighted in case studies. To address the above themes, we have proposed a revised decision tree, which expands on the guidance by the IQ MABEL Working Group (Leach et al. 2021). This approach facilitates a more refined recommendation of FIH dose selection for immunomodulators, allowing for a nuanced consideration of their mechanisms of action (MOAs) and the associated risk-to-benefit ratio, among other factors.

Preclinical Toxicity Assessment of Polyphenols-Based Standardized Extract of Cinnamomum zeylanicum Bark

Background: Cinnamon (Cinnamomum zeylanicum) bark is used as a spice in culinary practices and has been documented for health and medicinal benefits. Polyphenol (PP) is the major bioactive constituent of cinnamon bark. However, acceptable and safe dose levels and toxicity information of oral exposure to PP-based standardized cinnamon bark extract (PP-CZ) are crucial for safe human consumption. Objective: To evaluate PP-CZ for acute oral, subchronic oral toxicities in vivo, mutagenicity in vitro and genotoxic potential in vitro. Method:. The effects of oral treatment with single- and 90-days repeated dose were evaluated in rates as per OECD Test 423 and 408, respectively. Effects on body weight, food and water intake, organ weight, hematology, biochemistry, and histology were recorded . Mutagenicity and genotoxicity were evaluated using Ames (OECD No. 471) and chromosomal aberrations (OECD Test. 473) tests. Results: A single oral dose of PP-CZ did not cause death or treatment-related toxic effects, indicating a “median lethal dose” > 2,000 mg/kg. In addition, a subchronic dosage (500 mg/kg/day, 90 days) was found safe in rats, suggesting “no observed adverse effect level” (NOAEL) of 500 mg/kg and “Human Equivalent Dose” (HED) of 4.8 g/day. Furthermore, the absence of mutagenicity or genotoxicity of PP-CZ was observed during in vitro tests. PP-CZ showed a robust safety profile without mutagenicity or genotoxicity in rats.

First Biodistribution Study of [68Ga]Ga-NOTA-Insulin Following Intranasal Administration in Adult Vervet Monkeys.

Intranasal insulin (INI) is being explored as a treatment for Alzheimer's disease (AD). Improved memory, functional ability, and cerebrospinal fluid (CSF) AD biomarker profiles have been observed following INI administration. However, the method of intranasal delivery may significantly affect outcomes. To show reliable delivery of insulin to the brain using the Aptar Cartridge Pump System (CPS) intranasal delivery system. To visualize INI biodistribution, we developed a novel PET radiotracer, Gallium 68-radiolabeled (NOTA-conjugated) insulin, [68Ga]Ga-NOTA-insulin. We used the Aptar CPS to administer [68Ga]Ga-NOTA-insulin to anesthetized healthy adult vervet monkeys and measured brain regional activity and whole-body dosimetry following PET/CT scans. We observed brain penetration of [68Ga]Ga-NOTA-insulin following intranasal administration with the Aptar CPS. Radioactive uptake was seen in multiple regions, including the amygdala, putamen, hypothalamus, hippocampus, and choroid plexus. A safety profile and whole-body dosimetry were also established in a second cohort of vervets. Safety was confirmed: vitals remained stable, blood glucose levels were unchanged, and no organ was exposed to more than 2.5 mSv of radioactivity. Extrapolations from vervet organ distribution allowed for estimation of the [68Ga]Ga-NOTA-insulin absorbed dose in humans, and the maximum dose of [68Ga]Ga-NOTA-insulin that can be safely administered to humans was determined to be 185 MBq. The use of [68Ga]Ga-NOTA-insulin as a PET radiotracer is safe and effective for observing brain uptake in vervet monkeys. Further, the Aptar CPS successfully targets [68Ga]Ga-NOTA-insulin to the brain. The data will be essential in guiding future studies of intranasal [68Ga]Ga-NOTA-insulin administration in humans.

Pain hypersensitivity, sensorimotor impairment, and decreased muscle force in a novel rat model of radiation-induced peripheral neuropathy.

Radiation-induced peripheral neuropathy is a rare, but serious complication often resulting in profound morbidity, life-long disability, and chronic debilitating pain. Unfortunately, this type of peripheral neuropathy is usually progressive, and almost always irreversible. To date, a standardized rat model of radiation-induced peripheral neuropathy has not been established. The purpose of the present study was to examine neuropathic pain, sensorimotor impairment, and muscle force parameters following the administration of a clinically relevant radiation dose in a rat model. Ten rats were randomly assigned to one of two experimental groups: (1) radiation and (2) sham-radiated controls. Radiated animals were given a clinically relevant dose of 35 Gray (Gy) divided into five daily doses of 7 Gy/day. This regimen represents a human equivalent dose of 70 Gy, approximating the same dosage utilized for radiotherapy in oncologic patients. Sham-radiated controls were anesthetized and placed in the radiation apparatus but were not given radiation. All animals were tested for baseline values in both sensorimotor and pain behavioral tests. Sensorimotor testing consisted of the evaluation of walking tracks with the calculation of the Sciatic Functional Index (SFI). Pain-related behavioral measures consisted of mechanical allodynia (von Frey test), cold allodynia (Acetone test), and thermal allodynia (Hargreaves test). Animals were tested serially over an 8-week period. At the study endpoint, electrophysiological and muscle force assessments were completed, and histomorphometric analysis was performed on all sciatic nerves. Animals that underwent radiation treatment displayed significantly greater pain hypersensitivity to mechanical stimulation as compared to sham radiated controls from weeks 4 to 8 of testing. SFI values indicated sensorimotor impairments in the overground gait of radiated animals as compared to non-radiated animals. Furthermore, radiated animals displayed reduced twitch and tetanic muscle force when compared to sham radiated controls. A clinically relevant human equivalent dose of fractionated 35 Gy in rats established significant pain hypersensitivity, impairments in sensorimotor locomotion, and decreased muscle force capacity. This novel rodent model of radiation-induced peripheral neuropathy can be utilized to assess the potential efficacy of therapeutic treatments to either prevent or remediate this clinically debilitating condition.

Detoxification of Paraquat: Scooping up the Moon from the Water?

Review Detoxification of Paraquat: Scooping up the Moon from the Water? Yanyan Zhu and Xiuping Chen * State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao SAR, 519000, China * Correspondence: xpchen@um.edu.mo; Tel.: +853-88224679 Received: 9 May 2024; Revised: 6 June 2024; Accepted: 12 June 2024; Published: 23 August 2024 Abstract: Paraquat poisoning is a global public health problem, particularly in the Asia-Pacific region. Ingestion of even small amounts of paraquat can be life-threatening. However, there is no specific antidote for this pesticide, which has a low lethal dose and high lethality in humans. Paraquat poisoning causes systemic toxicity with the primary target organ being the lungs, resulting in acute alveolitis and pulmonary fibrosis. It can also lead to multiple organ failure. This review summarizes the current clinical management of patients with paraquat poisoning and the potentially effective compounds reported in the literature and patents for the treatment of paraquat poisoning. It also summarizes future directions for antidote development based on reports of available potential antidotes and provides ideas for paraquat antidote development.

Dynamic PET reveals compartmentalized brain and lung tissue antibiotic exposures of tuberculosis drugs

Tuberculosis (TB) remains a leading cause of death, but antibiotic treatments for tuberculous meningitis, the deadliest form of TB, are based on those developed for pulmonary TB and not optimized for brain penetration. Here, we perform first-in-human dynamic 18F-pretomanid positron emission tomography (PET) in eight human subjects to visualize 18F-pretomanid biodistribution as concentration-time exposures in multiple compartments (NCT05609552), demonstrating preferential brain versus lung tissue partitioning. Preferential, antibiotic-specific partitioning into brain or lung tissues of several antibiotics, active against multidrug resistant (MDR) Mycobacterium tuberculosis strains, are confirmed in experimentally-infected mice and rabbits, using dynamic PET with chemically identical antibiotic radioanalogs, and postmortem mass spectrometry measurements. PET-facilitated pharmacokinetic modeling predicts human dosing necessary to attain therapeutic brain exposures. These data are used to design optimized, pretomanid-based regimens which are evaluated at human equipotent dosing in a mouse model of TB meningitis, demonstrating excellent bactericidal activity without an increase in intracerebral inflammation or brain injury. Importantly, several antibiotic regimens demonstrate discordant activities in brain and lung tissues in the same animal, correlating with tissue antibiotic exposures. These data provide a mechanistic basis for the compartmentalized activities of antibiotic regimens, with important implications for developing treatments for meningitis and other infections in compartments with unique antibiotic penetration.

BIO 300 Attenuates Whole Blood Transcriptome Changes in Mice Exposed to Total-Body Radiation.

Development of radiation medical countermeasures under the U.S. Food and Drug Administration Animal Rule requires the capability to translate an effective animal-to-human drug dose. One method of human dose translation is using a biomarker and determining drug doses that modulate the biomarker to the desired level. BIO 300 Oral Powder (BIO 300) is a prophylactic radiation medical countermeasure that is currently being developed following the Animal Rule. The present study aimed to identify biomarkers that can be used for human dose conversion by conducting transcriptomics of whole blood collected from BIO 300-treated CD2F1 mice in the presence and absence of total-body irradiation (TBI). Unirradiated mice were treated with vehicle or 50, 100, or 200 mg/kg BIO 300, and irradiated mice were treated with 200 mg/kg or BIO 300 or vehicle prior to TBI. Whole-blood samples were collected after the last dose of the drug and after irradiation. RNA sequencing demonstrated 100 and 200 mg/kg of BIO 300 doses caused significantly more differential gene expression at 48 h after drug dose compared to 50 mg/kg of BIO 300 (7648, 7680, and 55 significantly differently expressed genes, respectively). Interestingly, following TBI, there were no significantly differentially expressed genes between vehicle- and BIO 300-treated mice. Despite the lack of significant changes in gene expression, the transcriptomic profiles in both groups indicated differential changes in signaling pathways. Pathway analysis of the transcriptome profile from vehicle-treated/TBI mice revealed that many inflammatory signaling pathways were activated in these animals. Signaling pathways enriched in BIO 300-treated/TBI mice were involved in cellular stress and immune response and were predicted to be inhibited. In all, four signaling pathways of interest were identified that were differentially enriched in irradiated animals treated with BIO 300: pathogen-induced cytokine storm signaling, S100 family signaling, pulmonary fibrosis idiopathic signaling, and wound-healing signaling. These pathways should be explored to identify potential biomarkers of BIO 300 that can be used for human dose translation.

Targeted lipidomics-based study of radiation-induced metabolite profiles changes in plasma of total body irradiation cases

Purpose Lipidomics is an important tool for triaging exposed individuals, and helps early adoption of prevention and control strategies. The purpose of this study was to screen significantly perturbed lipids between pre- and post-irradiation of human plasma samples after total body irradiation (TBI) and explore potential radiation biomarkers for early radiation classification. Methods Plasma samples were collected before and after irradiation from 22 hospitalized cases of acute myeloid leukemia (AML) prepared for bone marrow transplantation. Acute total-body γ irradiation was performed at doses of 0, 4, 8, and 12 Gy. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with multiple reaction monitoring (MRM) method was utilized. Self-paired studies before and after irradiation were performed to screen potential lipid categorization markers and markers of dose-response relationships for radiation perturbation in humans. Based on the screened potential markers, a human TBI dose estimation model was developed. Results In total, 426 individual lipids from 14 major classes were quantified and 152 potential biomarkers with categorical characteristics were screened. A total of 80 lipids (32 TGs, 29 SMs, 9 FAs, 5 CEs, 5 PIs) were upregulated at 4 Gy, and a total of 91 lipids (39 SMs, 18 TGs, 15 HexCers, 7 CEs, 6 Cers, 3 LacCers, 2 LPEs, 1 PI) were upregulated at 12 Gy. Comparison of the ROC curves between the non-exposed and exposed groups at different doses showed AUC values ranging from 0.807 to 0.876. The metabolic pathways of potential lipid markers are mainly sphingolipid and glycerolipid metabolism, unsaturated fatty acid biosynthesis, fatty acid degradation and biosynthesis. Among the 13 dose-dependent radiosensitive lipids, CE (20:5), CE (18:1) and PI (18:2/18:2) were gradually incorporated into the TBI dose estimation model. Conclusion This study suggested that it was feasible to acquire quantitative lipid biomarker panels using targeted lipidomics platforms for rapid, high-throughput triage. Lipidomics strategies for radiation biodosimetry in humans were established with lipid biomarkers with good dose-response relationship.

Single and Combinations of Rosuvastatin, Celecoxib, and Colchicine Effects on Biochemical and CBC Parameters of Wistar Albino Rats

Drug resistance became a well-known problem in different areas of pharmacology, including anti-cancer therapy and antibiotics. The overcoming of drug resistance either by different drugs or doses, increases the risk of tissue toxicity. The combination of single FDA-approved drugs became one of the solutions shorting the time for new drug approval, and lowering the cost of manufacturing and transporting of drug to pharmacy shelves. Every day a new combination is investigated to narrow the gap in different pharmacological requirements. Lipid-lowering and anti-inflammatory drugs are widely used and are widely available globally. The study aimed to investigate four probabilities of combinations of three single drugs Rosuvastatine (Ro), Celecoxib (Ce), and Colchicine (Co) on biochemical and Complete Blood Count parameters (CBC) to evaluate the reliability and probable effects of these drugs on normal body function. Nine groups (n=6) of Wistar Albino Rats were inoculated with single and combinations of drugs for eight days using the maximum normal human doses of each drug, blood samples were collected in the middle, and at the end of the experiment. Results showed that combinations induced abnormal biochemical, and CBC parameters in ALT, AST, Creatinine, and RBC parameters in all but one (Rosuvastatine-Celecoxibe-Colchicine) of the combination. The study concluded that the combination could be used except that showed a higher level of abnormal physiological parameters, and percussions should taken by more pharmacological and physiological investigation in a bigger scale of studies including longer durations and different animal models before the combinations utilized by human.

Exposure to polystyrene microplastics during lactational period alters immune status in both male mice and their offspring

The widespread use of microplastics and their harmful effects on the environment have emerged as serious concerns. However, the effect of microplastics on the immune system of mammals, particularly their offspring, has received little attention. In this study, polystyrene microplastics (PS-MPs) were orally administered to male mice during lactation. Flow cytometry was used to assess the immune cells in the spleens of both adult male mice and their offspring. The results showed that mice exposed to PS-MPs exhibited an increase in spleen weight and an elevated number of B and regulatory T cells (Tregs), irrespective of dosage. Furthermore, the F1 male offspring of the PS-MPs-exposed group had enlarged spleens; an increased number of B cells, T helper cells (Th cells), and Tregs; and an elevated ratio of T helper cells 17 (Th17 cells) to Tregs and T helper cells 1 (Th1 cells) to T helper cells 2 (Th2 cells). These results suggested a pro-inflammatory state in the spleen. In contrast, in the F1 female offspring exposed to PS-MPs, the changes in splenic immune cells were less pronounced. In the F2 generation of mice with exposed to PS-MPs, minimal alterations were observed in spleen immune cells and morphology. In conclusion, our study demonstrated that exposure to real human doses of PS-MPs during lactation in male mice altered the immune status, which can be passed on to F1 offspring but is not inherited across generations.