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1.
Nanoscale ; 16(16): 8046-8059, 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38563130

The biomedical application of nanotechnology in cancer treatment has demonstrated significant potential for improving treatment efficiencies and ameliorating adverse effects. However, the medical translation of nanotechnology-based nanomedicines faces challenges including hazardous environmental effects, difficulties in large-scale production, and possible excessive costs. In the present study, we extracted and purified natural exosome-like nanoparticles (ELNs) from Phellinus linteus. These nanoparticles (denoted as P-ELNs) had an average particle size of 154.1 nm, displayed a negative zeta potential of -31.3 mV, and maintained stability in the gastrointestinal tract. Furthermore, P-ELNs were found to contain a diverse array of functional components, including lipids and pharmacologically active small-molecule constituents. In vitro investigations suggested that they exhibited high internalization efficiency in liver tumor cells (Hepa 1-6) and exerted significant anti-proliferative, anti-migratory, and anti-invasive effects against Hepa 1-6 cells. Strikingly, the therapeutic outcomes of oral P-ELNs were confirmed in an animal model of metastatic hepatocellular carcinoma by amplifying reactive oxygen species (ROS) and rebalancing the gut microbiome. These findings demonstrate the potential of P-ELNs as a promising oral therapeutic platform for liver cancer treatment.


Carcinoma, Hepatocellular , Exosomes , Gastrointestinal Microbiome , Liver Neoplasms , Reactive Oxygen Species , Animals , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/metabolism , Reactive Oxygen Species/metabolism , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Liver Neoplasms/metabolism , Humans , Mice , Cell Line, Tumor , Exosomes/metabolism , Exosomes/chemistry , Gastrointestinal Microbiome/drug effects , Basidiomycota/chemistry , Basidiomycota/metabolism , Nanoparticles/chemistry , Phellinus/chemistry , Cell Proliferation/drug effects , Cell Movement/drug effects , Administration, Oral
2.
J Chem Neuroanat ; 137: 102414, 2024 04.
Article En | MEDLINE | ID: mdl-38490283

Rat offspring who are exposed to an amorphous formula of curcumin (CUR) from the embryonic stage have anti-anxiety-like behaviors, enhanced fear extinction learning, and increased synaptic plasticity in the hippocampal dentate gyrus (DG). In the present study, we investigated the links between genes with altered methylation status in the neurogenic niche and enhanced neural functions after CUR exposure. We conducted methylation and RNA sequencing analyses of the DG of CUR-exposed rat offspring on day 77 after delivery. Methylation status and transcript levels of candidate genes were validated using methylation-sensitive high-resolution melting and real-time reverse-transcription PCR, respectively. In the CUR group, we confirmed the hypermethylation and downregulation of Gpr150, Mmp23, Rprml, and Pcdh8 as well as the hypomethylation and upregulation of Ppm1j, Fam222a, and Opn3. Immunohistochemically, reprimo-like+ hilar cells and protocadherin-8+ granule cells were decreased and opsin-3+ hilar cells were increased by CUR exposure. Both reprimo-like and opsin-3 were partially expressed on subpopulations of glutamic acid decarboxylase 67+ γ-aminobutyric acid-ergic interneurons. Furthermore, the transcript levels of genes involved in protocadherin-8-mediated N-cadherin endocytosis were altered with CUR exposure; this was accompanied by Ctnnb1 and Syp upregulation and Mapk14, Map2k3, and Grip1 downregulation, suggesting that CUR-induced enhanced synaptic plasticity is associated with cell adhesion. Together, our results indicate that functionally different genes have altered methylation and expression in different neuronal populations of the hippocampal neurogenic niche, thus enhancing synaptic plasticity after CUR exposure.


Curcumin , DNA Methylation , Hippocampus , Animals , Curcumin/pharmacology , Rats , DNA Methylation/drug effects , Hippocampus/metabolism , Hippocampus/drug effects , Female , Neurogenesis/drug effects , Neurogenesis/genetics , Male , Pregnancy , Rats, Sprague-Dawley , Neuronal Plasticity/drug effects , Neuronal Plasticity/genetics , Prenatal Exposure Delayed Effects/metabolism , Prenatal Exposure Delayed Effects/chemically induced
3.
Food Chem Toxicol ; 185: 114486, 2024 Mar.
Article En | MEDLINE | ID: mdl-38301995

Ochratoxin A (OTA) is a renal carcinogen in rats, and repeated administration induces karyomegaly in proximal tubular epithelial cells (PTECs) of the outer stripe of the outer medulla (OSOM) before inducing proliferative lesions. To investigate whether OTA induces micronuclei (MN) in PTECs, we performed an in vitro MN assay using rat renal NRK-52E PTECs after treatment for ≤21 days, and an in vivo OSOM MN assay in rats treated with OTA, other renal carcinogens, or non-carcinogenic renal toxicants for 4 or 13 weeks. The in vitro assay revealed an increased frequency of micronucleated cells from the acceptable dose level for cell viability, even after 21 days of treatment. The in vivo assay also revealed a dose- and treatment period-dependent increase in PTECs with γ-H2AX+ MN. OTA-specific gene expression profiling by OSOM RNA sequencing after week 13 revealed the altered expression of genes related to microtubule-kinetochore binding, the kinesin superfamily, centriole assembly, DNA damage repair, and cell cycle regulation. MN formation was also observed with other renal carcinogens that induce karyomegaly similarly to OTA. These results imply that γ-H2AX+ MN formation by OTA treatment is related to the induction of chromosomal instability accompanying karyomegaly formation before proliferative lesions form, providing a new insight into the carcinogenic mechanism that may be relevant to humans.


Ochratoxins , Humans , Rats , Animals , Ochratoxins/toxicity , Carcinogens , Epithelial Cells , Chromosomal Instability
4.
J Chem Neuroanat ; 131: 102285, 2023 09.
Article En | MEDLINE | ID: mdl-37150363

This study investigated the ameliorating effects of a natural antioxidant formula (NAF) consisting of Ginkgo biloba leaf extract, docosahexaenoic acid/eicosapentaenoic acid, ferulic acid, flaxseed oil, vitamin E, and vitamin B12 on a lipopolysaccharide (LPS)-induced cognitive dysfunction model in rats. Six-week-old rats received a diet containing 0.5% (w/w) NAF for 38 days from Day 1, and LPS (1 mg/kg body weight) was administered intraperitoneally once daily on Days 8 and 10. On Day 11, LPS alone increased interleukin-1ß and tumor necrosis factor-α in the hippocampus and cerebral cortex and the numbers of M1-type microglia/macrophages and GFAP+ reactive astrocytes in the hilus of the hippocampal dentate gyrus. NAF treatment decreased brain proinflammatory cytokine levels and increased the number of M2-type microglia/macrophages. During Days 34-38, LPS alone impaired fear memory acquisition and the extinction learning process, and NAF facilitated fear extinction learning. On Day 38, LPS alone decreased the number of type-3 neural progenitor cells in the hippocampal neurogenic niche, and NAF restored the number of type-3 neural progenitor cells and increased the numbers of both immature granule cells in the neurogenic niche and reelin+ hilar interneurons. Thus, NAF exhibited anti-inflammatory effects and ameliorated LPS-induced adverse effects on hippocampal neurogenesis and fear memory learning, possibly through amplification of reelin signaling by hilar interneurons. These results suggest that neuroinflammation is a key factor in the development of LPS-induced impairment of fear memory learning, and supplementation with NAF in the present study helped to prevent hippocampal neurogenesis and disruptive neurobehaviors caused by neuroinflammation.


Fear , Lipopolysaccharides , Rats , Animals , Lipopolysaccharides/pharmacology , Fear/physiology , Antioxidants/pharmacology , Neuroinflammatory Diseases , Extinction, Psychological , Hippocampus , Neurogenesis , Memory Disorders/chemically induced , Memory Disorders/drug therapy , Memory Disorders/pathology
5.
Anim Nutr ; 13: 270-281, 2023 Jun.
Article En | MEDLINE | ID: mdl-37168452

Osteoporosis is a common degenerative metabolic bone disease in caged laying hens. Intensive egg production mobilizing large amounts of Ca from bone for eggshell formation, consequently leading to Ca deficiency, has been recognized as a critical factor causing osteoporosis in commercial laying hens. The aim of this study was to examine the effect of Ca deficiency on the function of the gut microbiota-bone axis and related egg production traits and bone health in laying hens. Twenty-four 48-week-old laying hens were fed a control diet (Control, 3.72%) or a low Ca diet (LC, 2.04%) for 60 d (n = 12). Compared to the Control hens, the LC hens had higher levels of alkaline phosphatase and tartrate resistant acid phosphatase (P < 0.05) with lower bone strength, eggshell thickness, and eggshell strength (P < 0.05). In addition, the LC hens had higher plasma estradiol concentrations, while having lower concentrations of interleukin-1 (IL-1) and IL-6. The LC hens also had a lower pH value in the ileum with an increased Ca retention. The principal co-ordinates analysis showed significantly separate cecal microbiota populations between the Control and LC hens. The Prevotellaceae_UCG-001, Subdoligranulum, Peptococcus, and Eubacterium_hallii_group (P < 0.05) were higher, while the CHKC1001 and Sutterella (P < 0.05) were lower at the genus level in the LC hens. In addition, Prevotellaceae_UCG-001, Subdoligranulum and Eubacterium_hallii_group had a negative correlation, while Sutterella was positively correlated with ileal pH values. The transcriptome analysis revealed that the low Ca diet caused 20 and 31 genes to be significantly up- and down-regulated, respectively. The gene expressions of cystic fibrosis transmembrane conductance regulator, solute carrier family 26 member 3 of the anion exchangers, and mitogen-activated protein kinase 12 of pro-inflammatory factors were lower in the LC birds, which was correlated with the lower ileal pH values. These results suggest that the hens with low Ca diet-induced osteoporosis have an increased intestinal Ca retention with a decreased ileal pH value, correlated with the changes in Prevotellaceae_UCG-001, Subdoligranulum, and Eubacterium_hallii_group of beneficial genera. The results provide insights for further understanding and preventing osteoporosis in laying hens.

6.
Food Chem Toxicol ; 177: 113814, 2023 Jul.
Article En | MEDLINE | ID: mdl-37179047

Enniatins are emerging mycotoxins that contaminate foods. The present study investigated the oral pharmacokinetics and 28-day repeated-dose oral toxicity of enniatin B (ENNB) in CD1 (ICR) mice. In the pharmacokinetic study, male mice received a single oral or intravenous dose of ENNB [30 mg/kg body weight (BW) and 1 mg/kg BW, respectively]. After oral dosing, ENNB exhibited 139.9% bioavailability, a 5.1-h elimination half-life, 5.26% fecal excretion from 4 to 24 h post-dose, and upregulation of Cyp7a1, Cyp2a12, Cyp2b10, and Cyp26a1 in the liver 2 h post-dosing. In the 28-day toxicity study, ENNB was administered to male and female mice by oral gavage at 0, 7.5, 15, and 30 mg/kg BW/day. Females (7.5 and 30 mg/kg) showed dose-unrelated decreased food consumption without accompanying changes in clinical parameters. Males (30 mg/kg) showed low red blood cell counts and high blood urea nitrogen levels and absolute kidney weights; however, other related parameters including the histopathology of systemic organs/tissues were unchanged. These results suggest that ENNB may not induce toxicity after 28 days of oral administration in mice, despite high absorption. The no-observed-adverse-effect level of ENNB after 28 days of repeated oral doses was 30 mg/kg BW/day for both sexes of mice.


Liver , Mice , Male , Female , Animals , Mice, Inbred ICR , No-Observed-Adverse-Effect Level , Administration, Oral
8.
Early Child Educ J ; 51(2): 371-381, 2023.
Article En | MEDLINE | ID: mdl-35125856

This study aimed to investigate the online teaching experiences of preservice teachers during the pandemic. Due to COVID-19, preservice teachers were required to work with children and families remotely to gain practicum experiences. Three preservice teachers' work (family reflection papers, lesson reflection papers, video recordings of teaching, eBooks, and teaching movies) from two courses were analyzed using constant comparative analysis. The study findings indicated that preservice teachers struggled with maintaining children's active engagement and identifying appropriate time to scaffold children's learning since they could not observe the learning process of the children. However, they were able to overcome the challenges by employing different strategies (modeling, child-centered approach, and patience), with these attempts reflecting their pedagogical resilience.

9.
Neurotox Res ; 40(6): 2203-2220, 2022 Dec.
Article En | MEDLINE | ID: mdl-36098941

Lead (Pb) causes developmental neurotoxicity. Developmental exposure to Pb acetate (PbAc) induces aberrant hippocampal neurogenesis by increasing or decreasing neural progenitor cell (NPC) subpopulations in the dentate gyrus (DG) of rats. To investigate whether hippocampal neurogenesis is similarly affected by PbAc exposure in a general toxicity study, 5-week-old Sprague-Dawley rats were orally administered PbAc at 0, 4000, and 8000 ppm (w/v) in drinking water for 28 days. After exposure to 4000 or 8000 ppm PbAc, Pb had accumulated in the brains. Neurogenesis was suppressed by 8000 ppm PbAc, which was related to decreased number of type-2b NPCs, although number of mature granule cells were increased by both PbAc doses. Gene expression in the 8000 ppm PbAc group suggested suppressed NPC proliferation and increased apoptosis resulting in suppressed neurogenesis. PbAc exposure increased numbers of metallothionein-I/II+ cells and GFAP+ astrocytes in the DG hilus, and upregulated Mt1, antioxidant genes (Hmox1 and Gsta5), and Il6 in the DG, suggesting the induction of oxidative stress and neuroinflammation related to Pb accumulation resulting in suppressed neurogenesis. PbAc at 8000 ppm also upregulated Ntrk2 and increased the number of CALB2+ interneurons, suggesting the activation of BDNF-TrkB signaling and CALB2+ interneuron-mediated signals to ameliorate suppressed neurogenesis resulting in increased number of newborn granule cells. PbAc at both doses increased the number of ARC+ granule cells, suggesting the facilitation of synaptic plasticity of newborn granule cells through the activation of BDNF-TrkB signaling. These results suggest that PbAc exposure during the young-adult stage disrupted hippocampal neurogenesis, which had a different pattern from developmental exposure to PbAc. However, the induction of oxidative stress/neuroinflammation and activation of identical cellular signals occurred irrespective of the life stage at PbAc exposure.


Neural Stem Cells , Prenatal Exposure Delayed Effects , Rats , Animals , Female , Humans , Brain-Derived Neurotrophic Factor/metabolism , Lead , Neuroinflammatory Diseases , Rats, Sprague-Dawley , Apoptosis , Hippocampus/metabolism , Neurogenesis/physiology , Dentate Gyrus , Neural Stem Cells/metabolism , Neuronal Plasticity , Prenatal Exposure Delayed Effects/metabolism
10.
J Appl Toxicol ; 42(5): 864-882, 2022 05.
Article En | MEDLINE | ID: mdl-34779009

We have previously reported that the valproic acid (VPA)-induced disruption pattern of hippocampal adult neurogenesis differs between developmental and 28-day postpubertal exposure. In the present study, we performed brain region-specific global gene expression profiling to compare the profiles of VPA-induced neurotoxicity between developmental and postpubertal exposure. Offspring exposed to VPA at 0, 667, and 2000 parts per million (ppm) via maternal drinking water from gestational day 6 until weaning (postnatal day 21) were examined, along with male rats orally administered VPA at 0, 200, and 900 mg/kg body weight for 28 days starting at 5 weeks old. Four brain regions-the hippocampal dentate gyrus, corpus callosum, cerebral cortex, and cerebellar vermis-were subjected to expression microarray analysis. Profiled data suggested a region-specific pattern of effects after developmental VPA exposure, and a common pattern of effects among brain regions after postpubertal VPA exposure. Developmental VPA exposure typically led to the altered expression of genes related to nervous system development (Msx1, Xcl1, Foxj1, Prdm16, C3, and Kif11) in the hippocampus, and those related to nervous system development (Neurod1) and gliogenesis (Notch1 and Sox9) in the corpus callosum. Postpubertal VPA exposure led to the altered expression of genes related to neuronal differentiation and projection (Cd47, Cyr61, Dbi, Adamts1, and Btg2) in multiple brain regions. These findings suggested that neurotoxic patterns of VPA might be different between developmental and postpubertal exposure, which was consistent with our previous study. Of note, the hippocampal dentate gyrus might be a sensitive target of developmental neurotoxicants after puberty.


Neurotoxicity Syndromes , Prenatal Exposure Delayed Effects , Animals , Brain , Hippocampus , Male , Neurogenesis , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/metabolism , Rats , Sexual Maturation , Transcriptome , Valproic Acid/metabolism , Valproic Acid/toxicity
11.
Animals (Basel) ; 11(7)2021 Jul 08.
Article En | MEDLINE | ID: mdl-34359169

This study was to investigate the effects of Bacillus subtilis on production performance and bone pathophysiological characteristics of layers. Twenty-four 48-week-old Lohmann Pink-shell laying hens were randomly divided into two groups: a basic diet (control) and the basic diet mixed with Bacillus subtilis (0.5 g/kg) for a 60-day trial. Statistically, independent-sample t-test was used to assess the treatment differences. The results showed that Bacillus subtilis supplementation improved the percent of marketable eggs (p < 0.05) with reduced numbers of broken and soft-shelled eggs but had no effects on egg weight, height of albumen, yolk color, and Haugh unit (p > 0.05). Bacillus subtilis supplement also elevated maximum load (p = 0.06), maximum stress (p = 0.01), stiffness (p < 0.01), and Young's modulus (p < 0.01) but suppressed maximum strain (p = 0.06) in the femur. In addition, compared with control birds, phosphorous concentration (p < 0.01) was reduced in serum at day 61 but increased in the femur (p < 0.05) in Bacillus subtilis fed birds. Bacillus subtilis fed birds also had lower magnesium concentrations in both femur (p = 0.04) and feces (p = 0.09). Furthermore, Bacillus subtilis increased plasma estrogen concentration (p = 0.01) and femur TNF receptor superfamily member 11b (OPG) expression (p < 0.05) but reduced plasma IL-1 (p < 0.01) and TNF-α (p < 0.01) concentrations. These results indicate that Bacillus subtilis could be used as a health promotor to reduce overproduction-induced inflammation and associated bone damage and to increase marketable egg production. The data provide evidence for developing a management strategy to use Bacillus subtilis as a feed additive to improve marketable egg production and health and welfare status of laying hens.

12.
Toxicol Lett ; 349: 69-83, 2021 Oct 01.
Article En | MEDLINE | ID: mdl-34126181

Exposure to sterigmatocystin (STC) raises concerns on developmental neurological disorders. The present study investigated the effects of maternal oral STC exposure on postnatal hippocampal neurogenesis of offspring in rats. Dams were exposed to STC (1.7, 5.0, and 15.0 ppm in diet) from gestational day 6 until day 21 post-delivery (weaning), and offspring were maintained without STC exposure until adulthood on postnatal day (PND) 77, in accordance with OECD chemical testing guideline Test No. 426. On PND 21, 15.0-ppm STC decreased type-3 neural progenitor cell numbers in the subgranular zone (SGZ) due to suppressed proliferation. Increased γ-H2AX-immunoreactive (+) cell numbers in the SGZ and Ercc1 upregulation and Brip1 downregulation in the dentate gyrus suggested induction of DNA double-strand breaks in SGZ cells. Upregulation of Apex1 and Ogg1 and downregulation of antioxidant genes downstream of NRF2-Keap1 signaling suggested induction of oxidative DNA damage. Increased p21WAF1/CIP1+ SGZ cell numbers and suppressed cholinergic signaling through CHRNB2-containing receptors in GABAergic interneurons suggested potential neurogenesis suppression mechanisms. Multiple mechanisms involving N-methyl-d-aspartate (NMDA) receptor-mediated glutamatergic signaling and various GABAergic interneuron subpopulations, including CHRNA7-expressing somatostatin+ interneurons activated by BDNF-TrkB signaling, may be involved in ameliorating the neurogenesis. Upregulation of Arc, Ptgs2, and genes encoding NMDA receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors suggested synaptic plasticity facilitation. On PND 77, ARC+ granule cells decreased, and Nos2 was upregulated following 15.0 ppm STC exposure, suggesting oxidative stress-mediated synaptic plasticity suppression. Inverse pattern in gene expression changes in vesicular glutamate transporter isoforms, Slc17a7 and Slc17a6, from weaning might also be responsible for the synaptic plasticity suppression. The no-observed-adverse-effect level of maternal oral STC exposure for offspring neurogenesis was determined to be 5.0 ppm, translating to 0.34-0.85 mg/kg body weight/day.


Cell Proliferation/drug effects , Dentate Gyrus/drug effects , Neural Stem Cells/drug effects , Neurogenesis/drug effects , Neuronal Plasticity/drug effects , Sterigmatocystin/toxicity , Animals , Apoptosis/drug effects , DNA Breaks, Double-Stranded , Dentate Gyrus/metabolism , Dentate Gyrus/pathology , Dose-Response Relationship, Drug , Gene Expression Regulation , Neural Stem Cells/metabolism , Neural Stem Cells/pathology , No-Observed-Adverse-Effect Level , Oxidative Stress/drug effects , Rats, Sprague-Dawley , Receptors, Neurotransmitter/genetics , Receptors, Neurotransmitter/metabolism , Weaning
13.
Toxicology ; 456: 152782, 2021 05 30.
Article En | MEDLINE | ID: mdl-33862172

Lead (Pb) exposure causes cognitive deficits in children. The present study investigated the effect of developmental exposure to Pb acetate (PbAc) on postnatal hippocampal neurogenesis. Pregnant rats were administered drinking water containing 0, 2000, or 4000 ppm PbAc from gestational day 6 until day 21 post-delivery (weaning), and offspring were maintained without PbAc exposure until adulthood on postnatal day (PND) 77. There was a dose-related accumulation of Pb in the offspring brain at weaning, while Pb was mainly excreted in adulthood. In the hippocampus, metallothionein I/II immunoreactive (+) glia were increased through adulthood as a neuroprotective response to accumulated Pb, accompanied by increased astrocyte and microglia numbers in adulthood, suggesting sustained neural damage. Gene expression changes suggested elevated oxidative stress at weaning and suppression of the antioxidant system in adulthood, as well as continued neuroinflammatory responses. At weaning, granule cell apoptosis was increased and numbers of type-3 neural progenitor cells (NPCs) were decreased. By contrast, type-2a and type-2b NPCs were increased, suggesting suppressed differentiation to type-3 NPCs. In adulthood, there were increased numbers of immature granule cells. In the hilus of the dentate gyrus, somatostatin+ interneurons were increased at weaning, while calbindin-D-29K+ interneurons were increased throughout adulthood, suggesting a strengthened interneuron regulatory system against the suppressed differentiation at weaning. In the dentate gyrus, Bdnf, Ntrk2, and Chrna7 gene expression were upregulated and numbers of hilar TrkB+ interneurons increased at weaning. These findings suggest activation of BDNF-TrkB signaling to increase somatostatin+ interneurons and promote cholinergic signaling, thus increasing later production of immature granule cells. In adulthood, Pcna and Apex1 gene expression were downregulated and Chek1 and cyclin-dependent kinase inhibitor expression were upregulated. Furthermore, there was an increase in γ-H2AX+ SGZ cells, suggesting induction of cellular senescence of SGZ cells due to Pb genotoxicity.


Brain-Derived Neurotrophic Factor/biosynthesis , Cellular Senescence/drug effects , Hippocampus/drug effects , Neurogenesis/drug effects , Organometallic Compounds/toxicity , Receptor, trkB/biosynthesis , Animals , Cellular Senescence/physiology , Dose-Response Relationship, Drug , Female , Hippocampus/growth & development , Hippocampus/metabolism , Male , Neurogenesis/physiology , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/metabolism , Rats , Signal Transduction/drug effects , Signal Transduction/physiology
14.
J Toxicol Sci ; 46(4): 157-165, 2021.
Article En | MEDLINE | ID: mdl-33814509

Enniatins are so-called "emerging mycotoxins" that commonly occur in milligrams per kilogram levels in grains and their derived products, as well as in fish, dried fruits, nuts, spices, cocoa, and coffee. The present study investigated the 28-day repeated oral dose toxicity of enniatin complex in CD1(ICR) mice. Enniatin B, enniatin B1, and enniatin A1 at a ratio of 4:4:1 were administered to male and female mice at doses of 0 (vehicle controls), 0.8, 4, and 20 mg/kg body weight/day. In life parameters did not change during the study period, with the exception of slight reductions in food consumption in male mice administered 4 and 20 mg/kg and in female mice administered 20 mg/kg. Body and organ weights did not change, and no alterations in hematology, blood biochemistry, or histopathology parameters were observed at the end of the administration period. Thus, we determined that the no-observed-adverse-effect level of enniatin complex was 20 mg/kg/day for both sexes under the present experimental conditions.


Depsipeptides/administration & dosage , Depsipeptides/toxicity , Mycotoxins/administration & dosage , Mycotoxins/toxicity , Administration, Oral , Animals , Blood Chemical Analysis , Eating/drug effects , Female , Male , Mice, Inbred ICR , No-Observed-Adverse-Effect Level , Organ Size , Time Factors
15.
J Appl Toxicol ; 40(11): 1467-1479, 2020 11.
Article En | MEDLINE | ID: mdl-32596862

We previously found downregulation of low-density lipoprotein receptor class A domain-containing protein 4 (LDLRAD4), a negative regulator of transforming growth factor (TGF)-ß signaling, in glutathione S-transferase placental form (GST-P) expressing (+ ) pre-neoplastic lesions produced by treatment with nongenotoxic hepatocarcinogens for up to 90 days in rats. Here, we investigated the relationship between LDLRAD4 downregulation and TGFß signaling in nongenotoxic hepatocarcinogenesis. The transcripts of Tgfb and Hb-egf increased after ≥28 days of treatment. After 84 or 90 days, Snai1 increased transcripts and the subpopulation of GST-P+ foci downregulating LDLRAD4 co-expressed TGFß1, phosphorylated EGFR, or phosphorylated AKT2, and downregulated PTEN, showing higher incidences than those in GST-P+ foci expressing LDLRAD4. The subpopulation of GST-P+ foci downregulating LDLRAD4 also co-expressed caveolin-1 or TACE/ADAM17, suggesting that disruptive activation of TGFß signaling through a loss of LDLRAD4 enhances EGFR and PTEN/AKT-dependent pathways via caveolin-1-dependent activation of TACE/ADAM17 during nongenotoxic hepatocarcinogenesis. The numbers of c-MYC+ cells and PCNA+ cells were higher in LDLRAD4-downregulated GST-P+ foci than in LDLRAD4-expressing GST-P+ foci, suggesting a preferential proliferation of pre-neoplastic cells by LDLRAD4 downregulation. Nongenotoxic hepatocarcinogens markedly downregulated Nox4 after 28 days and later decreased cleaved caspase 3+ cells in LDLRAD4-downregulated GST-P+ foci, suggesting an attenuation of apoptosis by LDLRAD4 downregulation through activation of the EGFR pathway. At the late hepatocarcinogenesis stage in a two-stage model, LDLRAD4 downregulation was higher in adenoma and carcinoma than in pre-neoplastic cell foci, suggesting a role of LDLRAD4 downregulation in tumor development. Our results suggest that nongenotoxic hepatocarcinogens cause disruptive activation of TGFß signaling through downregulating LDLRAD4 toward carcinogenesis in the rat liver.


Apoptosis , Cell Proliferation , Cell Transformation, Neoplastic/metabolism , Chemical and Drug Induced Liver Injury/metabolism , Liver Neoplasms/metabolism , Liver/metabolism , Precancerous Conditions/metabolism , Transforming Growth Factor beta/metabolism , Animals , Carbon Tetrachloride , Cell Transformation, Neoplastic/chemically induced , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/genetics , Chemical and Drug Induced Liver Injury/pathology , Diethylnitrosamine , Disease Models, Animal , Down-Regulation , Gene Expression Regulation, Neoplastic , Liver/pathology , Liver Neoplasms/chemically induced , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Methapyrilene , Precancerous Conditions/chemically induced , Precancerous Conditions/genetics , Precancerous Conditions/pathology , Rats, Inbred F344 , Signal Transduction , Thioacetamide , Time Factors , Transforming Growth Factor beta/genetics
16.
FASEB J ; 34(1): 1783-1801, 2020 01.
Article En | MEDLINE | ID: mdl-31914584

The natural product icariin (ICA) and its phosphorylated derivatives (pICA) have been shown to have outstanding anti-inflammatory and antioxidant properties. This study was to explore the protective effects of ICA and pICA on the intestinal epithelium of enterotoxigenic Escherichia coli (ETEC)-induced piglet diarrhea and its underlying mechanisms in vivo and in vitro. ETEC K88 increased pro-inflammatory cytokine expression, activated oxidative stress and inhibited antioxidant enzyme activity, induced phosphorylated p38 MAPK gene and protein expression, disrupted intestinal barrier function, and led to diarrhea in piglets. Pretreatment with ICA and pICA effectively alleviated ETEC-induced intestinal barrier dysfunction in vivo and in vitro. Pretreatment with p38 MAPK inhibitor (SB203580) significantly rescued the IPEC-J2 cells barrier function damaged by ETEC challenge. However, pretreatment with p38 MAPK activator (anisomycin) did not alleviated the IPEC-J2 cells barrier function damaged by ETEC challenge. Our data demonstrated that ICA and pICA regulate the inflammatory response and oxidative stress of intestinal epithelial cells by inhibiting the expression of p38 MAPK, thereby alleviating ETEC K88-induced disruption of intestinal barrier function and intestinal permeability. These findings provide new insights into the prevention and treatment of intestinal barrier dysfunction induced by ETEC K88.


Enterotoxigenic Escherichia coli/pathogenicity , Epithelial Cells/metabolism , Escherichia coli Infections/metabolism , Flavonoids/metabolism , Intestinal Mucosa/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Bacterial Adhesion/physiology , Cell Line , Diarrhea/metabolism , Diarrhea/microbiology , Epithelial Cells/microbiology , Escherichia coli Infections/microbiology , Intestinal Diseases/metabolism , Intestinal Diseases/microbiology , Intestinal Mucosa/microbiology , Intestines/microbiology , Male , Permeability , Swine , Swine Diseases/metabolism , Swine Diseases/microbiology
18.
J Toxicol Pathol ; 32(4): 261-274, 2019 Oct.
Article En | MEDLINE | ID: mdl-31719753

To clarify difference in the responses on the reprogramming of metabolism toward carcinogenesis between genotoxic and non-genotoxic hepatocarcinogens in the liver, rats were repeatedly administered genotoxic hepatocarcinogens (N-nitrosodiethylamine, aflatoxin B1, N-nitrosopyrrolidine, or carbadox) or non-genotoxic hepatocarcinogens (carbon tetrachloride, thioacetamide, or methapyrilene hydrochloride) for 28, 84, or 90 days. Non-genotoxic hepatocarcinogens revealed transcript expression changes suggestive of suppressed mitochondrial oxidative phosphorylation (OXPHOS) after 28 days and increased glutathione S-transferase placental form-positive (GST-P+) foci downregulating adenosine triphosphate (ATP) synthase subunit beta, mitochondrial precursor (ATPB), compared with genotoxic hepatocarcinogens after 84 or 90 days, suggesting that non-genotoxic hepatocarcinogens are prone to suppress OXPHOS from the early stage of treatment, which is in contrast to genotoxic hepatocarcinogens. Both genotoxic and non-genotoxic hepatocarcinogens upregulated glycolytic enzyme genes and increased cellular membrane solute carrier family 2, facilitated glucose transporter member 1 (GLUT1) expression in GST-P+ foci for up to 90 days, suggesting induction of a metabolic shift from OXPHOS to glycolysis at early hepatocarcinogenesis by hepatocarcinogens unrelated to genotoxic potential. Non-genotoxic hepatocarcinogens increased c-MYC+ cells after 28 days and downregulated Tp53 after 84 or 90 days, suggesting a commitment to enhanced metabolic shift and cell proliferation. Genotoxic hepatocarcinogens also enhanced c-MYC activation-related metabolic shift until 84 or 90 days. In addition, both genotoxic and non-genotoxic hepatocarcinogens upregulated glutaminolysis-related Slc1a5 or Gls, or both, after 28 days and induced liver cell foci immunoreactive for neutral amino acid transporter B(0) (SLC1A5) in the subpopulation of GST-P+ foci after 84 or 90 days, suggesting glutaminolysis-mediated facilitation of cell proliferation toward hepatocarcinogenesis. These results suggest differential responses between genotoxic and non-genotoxic hepatocarcinogens on reprogramming of energy metabolic pathways toward carcinogenesis in liver cells from the early stage of hepatocarcinogen treatment.

19.
Biomed Pharmacother ; 118: 109246, 2019 Oct.
Article En | MEDLINE | ID: mdl-31387006

Icariin (ICA) and phosphorylated icariin (pICA) have excellent antiviral and antioxidant effects. However, whether ICA and pICA cause anti-LPS-induced intestinal damage remains unclear. In this study, we used Caco-2 cells as a model to investigate the protective effects of ICA and pICA on human colonic epithelial cells and explore their potential mechanisms. Our results indicated that ICA and pICA increased cell viability and decreased lactate dehydrogenase activity in Caco-2 cells. ICA and pICA also attenuated LPS-induced changes in intestinal epithelial cell permeability and reduced the levels of oxidative stress indicators, such as reactive oxygen species, malondialdehyde, and hydrogen peroxide, in Caco-2 cells. Antioxidant indicators, such as superoxide dismutase, glutathione peroxidase, catalase and total antioxidant capacity, were increased, while the levels of IL-1ß, IL-6, IL-8 and TNF-α were reduced in the ICA and pICA groups. Furthermore, ICA and pICA decreased the gene abundance and enzyme activities of caspase-3, -8, -9 and -10 in Caco-2 cells. Our data suggest that ICA and pICA effectively attenuated LPS-induced changes in the oxidative stress, inflammation, apoptosis and intestinal permeability of intestinal epithelial cells. These findings provide new insight for treating LPS-induced intestinal injury.


Epithelial Cells/pathology , Flavonoids/pharmacology , Intestines/pathology , Protective Agents/pharmacology , Apoptosis/drug effects , Caco-2 Cells , Cell Survival/drug effects , Epithelial Cells/drug effects , Humans , Inflammation/pathology , Lipopolysaccharides , Oxidation-Reduction , Phosphorylation/drug effects , Transcription Factor RelA/metabolism
20.
J Toxicol Pathol ; 32(3): 155-164, 2019 Jul.
Article En | MEDLINE | ID: mdl-31402807

To clarify the suppressive effects of astragalus injection (AI) on different stages of early hepatocarcinogenesis induced by weak promotion, SD rats initiated with a single intraperitoneal (i.p.) injection of N-diethylnitrosamine (DEN) at 200 mg/kg body weight and promoted with 0.5% piperonyl butoxide (PBO) in diet were repeatedly administered AI at 5 ml/kg body weight/day in the early postinitiation (EPI) or late postinitiation (LPI) period for 2 or 8 weeks, respectively. The number and area of glutathione S-transferase placental form (GST-P)-immunoreactive (+) foci tended to increase in the DEN+PBO group compared with the DEN-alone group. Among the PBO-promoted groups, number and area of GST-P+ foci did not visibly change in the DEN+PBO+AI-EPI group compared with the DEN+PBO group. In contrast, number and area of GST-P+ foci tended to decrease in the DEN+PBO+AI-LPI group compared with the DEN+PBO group. Number of Ki67+ cells was increased in the DEN+PBO group compared with the DEN-alone group and was decreased in both AI-administered groups compared with the DEN+PBO group. Gene expression analysis revealed that the DEN+PBO+AI-LPI group showed increased transcript levels of Ccne1, Cdkn1b, Rb1, Bax, Bcl2, Casp3, and Casp9 compared with the DEN+PBO group; however, the DEN+PBO+AI-EPI group did not show changes in the transcript levels of any genes examined compared with the DEN+PBO. These results suggest that AI administration during the LPI period caused weak suppression of hepatocarcinogenesis under weak promotion with a low PBO dose by the mechanism involving facilitation of cell cycle suppression causing G1/S arrest and apoptosis via the mitochondrial pathway. In addition, the results suggest that AI administration during the EPI period has no effect on weakly promoted hepatocarcinogenesis.

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