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1.
Chem Sci ; 15(14): 5192-5200, 2024 Apr 03.
Article En | MEDLINE | ID: mdl-38577355

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.

2.
ACS Appl Mater Interfaces ; 16(2): 2330-2340, 2024 Jan 17.
Article En | MEDLINE | ID: mdl-38165730

It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2 and C2H2 mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm-2 together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.

3.
ACS Nano ; 17(16): 15871-15882, 2023 Aug 22.
Article En | MEDLINE | ID: mdl-37526621

Due to their high capacity and sufficient Na+ storage, O3-NaNi0.5Mn0.5O2 has attracted much attention as a viable cathode material for sodium-ion batteries (SIBs). However, the challenges of complicated irreversible multiphase transitions, poor structural stability, low operating voltage, and an unstable oxygen redox reaction still limit its practical application. Herein, using O3-NaNi0.5Mn0.5-xSnxO2 cathode materials as the research model, a universal strategy based on bridging microstructure engineering and local electronic structure manipulation is proposed. The strategy can modulate the physical and chemical properties of electrode materials, so as to restrain the unfavorable and irreversible multiphase transformation, improve structural stability, manipulate redox potential, and stabilize the anion redox reaction. The effect of Sn substitution on the intrinsic local electronic structure of the material is articulated by density functional theory calculations. Meanwhile, the universal strategy is also validated by Ti substitution, which could be further extrapolated to other systems and guide the design of cathode materials in the field of SIBs.

4.
J Agric Food Chem ; 71(23): 9135-9147, 2023 Jun 14.
Article En | MEDLINE | ID: mdl-37265398

Flavonoids have always been considered as the chemical basis for the hypoglycemic effect of mulberry leaves. In the course of our search for hypoglycemic effect agents from natural sources, a systematic study was launched to explore prenylated flavonoids from mulberry leaves. Herein, chemical investigation led to the isolation of 10 characteristic prenylated flavonoids, including two new compounds (1 and 3). Their structures were elucidated based on spectroscopic data. All compounds exhibited good α-glucosidase inhibitory activity in vitro, among which compound 2 had the best activity (IC50 = 2.6 µM), better than acarbose (IC50 = 19.6 µM). Additional in vivo tests have further demonstrated compound that compound 2 has a good ability to reduce postprandial blood glucose. Then, multi-spectroscopic methods and molecular simulation studies were used to study the inhibition mechanism. The results showed that compound 2 was a mixed inhibition of α-glucosidase and the binding process was spontaneous, with van der Waals forces as the main driving force, followed by hydrogen bonding and electrostatic forces. The above studies enriched the chemical basis of mulberry leaves, and the application of computational chemistry also provided a reference for future research on such structures.


Flavonoids , Morus , Flavonoids/chemistry , Glycoside Hydrolase Inhibitors/chemistry , Morus/chemistry , alpha-Glucosidases/metabolism , Molecular Dynamics Simulation , Hypoglycemic Agents/chemistry , Spectrum Analysis , Plant Leaves/chemistry , Plant Extracts/pharmacology , Plant Extracts/analysis , Molecular Docking Simulation
5.
BMC Vet Res ; 18(1): 289, 2022 Jul 23.
Article En | MEDLINE | ID: mdl-35871002

BACKGROUND: This study investigated the effects of chronic heat stress on liver inflammatory injury and its potential mechanisms in broilers. Chickens were randomly assigned to the 1-week control group (Control 1), 1-week heat stress group (HS1), 2-week control group (Control 2), and a 2-week heat stress group (HS2) with 15 replicates per group. Broilers in the heat stress groups were exposed to heat stress (35 ± 2 °C) for 8 h/d for 7 or 14 consecutive days, and the rest of 26 hours/day were kept at 23 ± 2 °C like control group broilers. Growth performance and liver inflammatory injury were examined for the analysis of liver injury. RESULTS: The results showed that heat stress for 2 weeks decreased the growth performance, reduced the liver weight (P < 0.05) and liver index (P < 0.05), induced obvious bleeding and necrosis points. Liver histological changes found that the heat stress induced the liver infiltration of neutrophils and lymphocytes in broilers. Serum levels of AST and SOD were enhanced in HS1 (P < 0.01, P < 0.05) and HS2 (P < 0.01, P < 0.05) group, compared with control 1 and 2 group broilers. The MDA content in HS1 group was higher than that of in control 1 group broilers (P < 0.05). Both the gene and protein expression levels of HSP70, TLR4 and NF-κB in the liver were significantly enhanced by heat stress. Furthermore, heat stress obviously enhanced the expression of IL-6, TNF-α, NF-κB P65, IκB and their phosphorylated proteins in the livers of broilers. In addition, heat stress promoted the activation of NLRP3 with increased NLRP3, caspase-1 and IL-1ß levels. CONCLUSIONS: These results suggested that heat stress can cause liver inflammation via activation of the TLR4-NF-κB and NLRP3 signaling pathways in broilers. With the extension of heat stress time, the effect of heat stress on the increase of NF-κB and NLRP3 signaling pathways tended to slow down.


NF-kappa B , NLR Family, Pyrin Domain-Containing 3 Protein , Animals , Chickens/metabolism , Heat-Shock Response , Inflammation/veterinary , Liver/metabolism , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Signal Transduction , Toll-Like Receptor 4/metabolism
6.
Ecotoxicol Environ Saf ; 238: 113572, 2022 Jun 15.
Article En | MEDLINE | ID: mdl-35533447

Cigarette smoke is a common global environmental pollutant. Asthma, the most frequent allergic airway disease, is related to maternal exposure to cigarette smoke. Our previous studies demonstrated that prenatal exposure to nicotine (PNE), the major active product of smoking, impairs fetal thymopoiesis and CD4+ T cell development after birth. This study aimed to investigate whether PNE contributes to asthma susceptibility through CD4+ T cell development alterations. First, A PNE model was established by administering 3 mg/kg/day nicotine to maternal mice, and then an ovalbumin-induced asthma model was established in the offspring. Further, ß-catenin and downstream pathways were inhibited in vitro to confirm the molecular mechanisms underlying the phenotype observed during the in vivo phase. The results showed that PNE induced Th2 and Th17 biases at developmental checkpoints and aggravated asthma symptoms in the offspring. In fetuses, PNE up-regulated α7 nAChR, activated PI3K-AKT, promoted ß-catenin level increase, and established potential Th2- and Th17-biased gene expression patterns during thymopoiesis, which persisted after birth. Similar results were also observed in 1 µM nicotine-treated thymocytes in vitro. Moreover, inhibiting PI3K-AKT by LY294002 abrogated nicotine-mediated ß-catenin level increase and thymopoiesis abnormalities, and an α7 nAChR antagonist (α-btx) also reversed nicotine-induced PI3K-AKT activation. Our findings provide strong evidence that PNE is a risk factor for T cell deviation and postnatal asthma, and revealed that nicotine-induced ß-catenin level increase induces thymopoiesis abnormalities.


Asthma , Prenatal Exposure Delayed Effects , Animals , Asthma/chemically induced , Asthma/metabolism , CD4-Positive T-Lymphocytes/metabolism , Female , Humans , Mice , Nicotine/metabolism , Nicotine/toxicity , Phosphatidylinositol 3-Kinases/metabolism , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Proto-Oncogene Proteins c-akt/metabolism , Vitamins , beta Catenin/genetics , beta Catenin/metabolism
7.
Poult Sci ; 100(9): 101302, 2021 Sep.
Article En | MEDLINE | ID: mdl-34289428

Heat stress can affect the poultry production and immune status of broilers. Heat stress disrupts intestinal integrity and increases intestinal inflammation, which is related with body immune dysfunction. Chai Hu oral liquid used as an antipyretic and anti-inflammatory drug is widely used in exogenous fever of poultry, but its resistance to heat stress and the mechanism is still unclear. In this study, a chronic heat stressed broilers model was established to explore the mechanisms of broilers' immune function changes and the effects of Chai Hu oral liquid. In this study, a total of 480 broilers were randomly divided into 6 groups with 80 replicates. Heat stress (HS) group broilers were stressed at 35 ± 2°C for 5 or 10 consecutive d with 6 h/d. Heat stressed (for 5 or 10 d) broilers were given with Jieshu KangreSan (Positive), Chai Hu oral liquid high, middle and low dosage (CH-High, CH-Mid, CH-Low) by oral administration. Birds in control group were treated with the same volume of PBS only in 25 ± 2°C. All birds were sacrificed at last heat stress challenged day. Changes in immune function were assessed by immune organs index, serum IFN-γ level, gene and protein expressions of immune factors in spleen and bursa of Fabricius. Results from this experiment showed that heat stress enhanced the immune organs' edema by directly increased the organs indexes of spleen and bursa of Fabricius in broilers. Heat stress for 10 d also increased bursa of Fabricius HSP70 protein level and significantly lowered the spleen and bursa of Fabricius proteins expressions of IFN-α, IFN-ß, and IFN-γ in broilers. The IFN-ß and IFN-γ protein levels in spleen and bursa of Fabricius also decreased in heat stressed broilers for 5 d. The gene and protein expressions of TLR4 and TBK1 markedly decreased in spleen and bursa of Fabricius of broilers treated with chronic heat stress. Chai Hu oral liquid reduced edema of immune organs and elevated TLR4-TBK1 signaling pathway to release immune factors. Above results indicated that chronic heat stress induced impaired immune function by inhibiting TLR4-TBK1 signaling pathway, and Chai Hu oral liquid had effective protection of body's immune ability by enhancing this signaling pathway.


Bupleurum , Bursa of Fabricius , Animals , Chickens , Dietary Supplements , Heat-Shock Response , Immunity , Signal Transduction , Spleen , Toll-Like Receptor 4
8.
Ecotoxicol Environ Saf ; 207: 111272, 2021 Jan 01.
Article En | MEDLINE | ID: mdl-32927162

Tobacco smoke is a common global environmental pollutant. Maternal tobacco smoke/nicotine exposure has long-term toxic effects on immune organs. We previously found that prenatal nicotine exposure (PNE)-induced programmed immune diseases caused by fetal thymic hypoplasia, but the mechanism still unknown. Autophagy has important functions in maintaining thymopoiesis, whether autophagy was involved in PNE-inhibited fetal thymocytes development is also obscure. Therefore, this study aimed to investigate how nicotine changed the development of fetal thymocytes from the perspective of autophagy in vivo and in vitro. PNE model was established by 3 mg/kg nicotine administration in Balb/c mice from gestational day 9 to 18. The results showed that PNE reduced the percentage and absolute number of CD69-CD4+SP cells, suggesting a block of fetal thymocytes mature. PNE promoted autophagosome formation, autophagy related proteins (Beclin1, LC3I/II) expression, and upregulated α7 nAChR as well as AMPK phosphorylation in fetal thymus. Moreover, PNE promoted Bcl10 degradation via autophagy-mediated proteolysis and inhibited p65 activation, blocking the transition of thymocytes between the DP to SP stage. Further, primary thymocytes were treated with nicotine in vitro and showed induced autophagy in a dose- and time-dependent manner. In addition, nicotine-inhibited CD69-CD4+SP cells and the Bcl10/p-p65 pathway have been reversed by an autophagy inhibitor. The α7 nAChR specific antagonist abrogated nicotine-induced AMPK phosphorylation and autophagy initiation. In conclusion, our findings showed that PNE repressed the Bcl10/p-p65 development pathway of CD4+SP cells by triggering autophagy, and illuminated the developmental origin mechanism of programmed immune diseases in PNE offspring.


Hazardous Substances/toxicity , Nicotine/toxicity , Thymocytes/physiology , Animals , Autophagy/drug effects , B-Cell CLL-Lymphoma 10 Protein , Beclin-1 , Female , Fetus , Lymphocyte Activation , Male , Mice , Mice, Inbred BALB C , Pregnancy , Prenatal Exposure Delayed Effects , Thymocytes/drug effects , Thymocytes/immunology , Vitamins
9.
Toxicology ; 428: 152309, 2019 12 01.
Article En | MEDLINE | ID: mdl-31629012

The recession of regulatory T cells (Tregs) contributes to development of autoimmune disease. Our previous study suggested that prenatal nicotine exposure (PNE) inhibited Tregs frequency in offspring, but the mechanisms are still uncertain. This study aimed to explore the molecular mechanisms of PNE-induced Tregs inhibition from the perspective of cellular cholesterol homeostasis both in vivo and in vitro. PNE mice model were established by 3 mg/kg/d nicotine administration in Balb/c strain from gestational day (GD) 9 to GD 18. The results showed that PNE significantly decreased thymic Tregs frequency in neonatal offspring. The activation of mTOR and downregulation of p-STAT5/Foxp3 pathway of Tregs were observed in PNE offspring. Mechanism study found that PNE elevated ATP-binding cassette transporter G1 (ABCG1) expression and decreased intracellular cholesterol content of Tregs in offspring, indicating impaired intracellular cholesterol homeostasis. Similar results were observed in 1 µM nicotine-treated primary thymocytes in vitro. Further, cholesterol-replenishment can abrogate nicotine-induced mTOR activation and the following suppression of p-STAT5/Foxp3 pathway and Tregs frequency. In addition, Abcg1 siRNA transfection can partly reverse the nicotine-decreased intracellular cholesterol content and cell frequency of Tregs. In conclusion, this study showed that PNE could suppress Tregs development in female mice by up-regulating ABCG1-dependent cholesterol efflux, and suggested that PNE-induced thymic Tregs recession of offspring at early life was the developmental origin mechanism of immune dysfunction in later life.


Cholesterol/metabolism , Nicotine/toxicity , Prenatal Exposure Delayed Effects , T-Lymphocytes, Regulatory/drug effects , Animals , Cells, Cultured , Female , Male , Maternal-Fetal Exchange , Mice, Inbred BALB C , Pregnancy , Thymus Gland/cytology
10.
Toxicol Lett ; 315: 39-46, 2019 Oct 15.
Article En | MEDLINE | ID: mdl-31442585

The recession of regulatory T cells (Tregs) is pivotal for type 1 diabetes (T1D) progressing. Our previous study observed the decreased Tregs in prenatal nicotine exposure (PNE) offspring, but whether this led to the onset of T1D remains uncertain. Thus, this study aimed to investigate the effects of PNE on T1D susceptibility and the role of PNE-suppressed Tregs in T1D of female offspring. The decreased body weights and elevated blood glucose levels from postnatal day (PND) 21 to PND 42 indicated that PNE caused persistent impaired glucose homeostasis in offspring. The elevated serum glutamic acid decarboxylase autoantibody, the "Gold Standard" for the detection of T1D, was observed on PND 42, suggesting the early stage of T1D in PNE offspring during adolescence. The reduced pancreatic islet areas and beta cells number in PNE offspring were observed at neonatal period and became more severe during adolescence. In addition, PNE caused immune dysfunction in offspring, manifested as suppressed thymic Tregs percentage from PND 4 to PND 42 and splenic Tregs/Th17 ratio on PND 42. In conclusion, PNE resulted in metabolic changes of offspring that were consistent with T1D characteristics, which could be the consequence of Tregs recession from early life to adolescence.


Diabetes Mellitus, Type 1/chemically induced , Diabetes Mellitus, Type 1/physiopathology , Nicotine/toxicity , Prenatal Exposure Delayed Effects/chemically induced , T-Lymphocytes, Regulatory/drug effects , Animals , Female , Humans , Mice , Pregnancy
11.
Arch Toxicol ; 93(5): 1323-1335, 2019 05.
Article En | MEDLINE | ID: mdl-30805671

Our previous studies demonstrated that prenatal caffeine exposure (PCE) caused thymopoiesis inhibition, immune disorders, and airway remodeling in offspring, which raises the question of whether PCE is a risk factor for postnatal asthma. Meanwhile, the mechanism of PCE-induced thymopoiesis inhibition is not clear yet. Considering caffeine's pro-autophagy effects (lacking evidence in thymus) and the important role of autophagy in maintaining thymopoiesis, this study aimed to investigate whether PCE contributes to asthma susceptibility, and further explore the molecular mechanisms of thymopoiesis inhibition from the perspective of pro-autophagy effects of caffeine both in vivo and in vitro. The PCE mouse model was established by 96 mg/kg/day caffeine administration from gestational day (GD) 9-GD 18, and an asthma model was established on the offspring by ovalbumin sensitization and challenge. The results confirmed our hypothesis that PCE could suppress pulmonary CD4+T development and aggravate allergen-induced asthma symptoms in the offspring. In fetuses, PCE significantly suppressed A2AR-PKA signaling, upregulated Beclin1-LC3II autophagy, promoted Bcl10 degradation, reduced A20 expression, and inhibited CD4+T thymopoiesis. Similar results were also observed in 4 µM caffeine-treated thymocytes in vitro. Moreover, inhibiting A2AR by antagonist (SCH 58261) performed the same downstream biological effects as caffeine treatment, and autophagy inhibitor (BafilomycinA1) clearly abolished the caffeine-induced Bcl10 degradation and A20 suppression. In conclusion, our findings, for the first time, showed that PCE could attenuate CD4+T thymopoiesis and suppress pulmonary CD4+T development by directly enhancing autophagy in thymocytes, and provided a firm experimental evidence that PCE is a risk factor for postnatal asthma.


Asthma/etiology , Caffeine/toxicity , Prenatal Exposure Delayed Effects/physiopathology , Thymocytes/drug effects , Animals , Autophagy/drug effects , CD4-Positive T-Lymphocytes/metabolism , Caffeine/administration & dosage , Central Nervous System Stimulants/administration & dosage , Central Nervous System Stimulants/toxicity , Female , Male , Mice , Mice, Inbred BALB C , Pregnancy , Thymocytes/cytology
12.
Toxicol Lett ; 304: 30-38, 2019 Apr.
Article En | MEDLINE | ID: mdl-30605750

Clinical study showed that smoking during pregnancy deceased the thymus size in newborns. However, the long-term effect remains unclear. This study was aimed to observe the effects of prenatal nicotine exposure (PNE) on the development of thymus and the T-lymphocyte subpopulation in mice offspring from the neonatal to adulthood. Both the thymus weight and cytometry data indicated that PNE caused persistent thymic hypoplasia in male offspring from neonatal to adult period and transient changes in female offspring from neonatal to prepuberal period. Flow cytometry analysis disclosed a permanent decreased proportion and number of mature CD4 single-positive (SP) T cells in thymus of both sex. In addition, the PNE male offspring showed a more serious thymus atrophy in the ovalbumin (OVA)-sensitized model. Moreover, increased autophagic vacuole and elevated mRNA expression of Beclin 1 were noted in PNE fetal thymus. In conclusion, PNE offspring showed thymus atrophy and CD 4 SP T cell reduction at different life stages. Mechanically, PNE induced excessive autophagy in fetal thymocytes might be involved in these changes. All the results provided evidence for elucidating the PNE-induced programmed immune diseases.


CD4-Positive T-Lymphocytes/drug effects , Immune System Diseases/chemically induced , Nicotine/toxicity , Nicotinic Agonists/toxicity , Prenatal Exposure Delayed Effects , Thymocytes/drug effects , Thymus Gland/drug effects , Age Factors , Animals , Animals, Newborn , Autophagy/drug effects , Beclin-1/genetics , Beclin-1/metabolism , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/pathology , Female , Immune System Diseases/immunology , Immune System Diseases/metabolism , Immune System Diseases/pathology , Male , Maternal Exposure , Mice, Inbred BALB C , Ovalbumin/immunology , Phenotype , Pregnancy , Thymocytes/immunology , Thymocytes/metabolism , Thymocytes/pathology , Thymus Gland/immunology , Thymus Gland/metabolism , Thymus Gland/pathology
13.
Food Chem Toxicol ; 120: 24-31, 2018 Oct.
Article En | MEDLINE | ID: mdl-29958987

Caffeine is contained within many drinks and food that are consumed daily. Prenatal caffeine ingestion (PCI) is a risk factor for intrauterine growth retardation (IUGR). We previously observed that PCI inhibits scavenger receptor class B type I (SR-BI)-mediated cholesterol uptake in fetal adrenals, subsequently decreasing glucocorticoid synthesis and inducing IUGR. In the present study, we aimed to investigate the long-term effects of PCI on adrenal glucocorticoid synthesis in adult male offspring rats. After establishing the PCI-induced IUGR, adult male offspring was injected intraperitoneally with 5 mg/kg·d lipopolysaccharide (LPS) for 2 days to induce acute stress. We observed persistent inhibition of SR-BI expression in PCI adrenals before and after stress. Compared with the controls, the PCI offspring had higher corticosterone concentrations after stress. The serum cholesterol concentration was stable without intergroup differences before and after stress. The cholesterol concentration in PCI adrenals showed a higher decrease rate than that of the control after stress. In summary, PCI induced long-term alterations in SR-BI expression and glucocorticoid synthesis in adult male offspring rat adrenals. Cholesterol has to be over-consumed in PCI adrenals against acute stress. This study provides an experimental basis to explain the susceptibility of IUGR offspring to metabolic diseases in adults.


Adrenal Glands/drug effects , Caffeine/pharmacology , Glucocorticoids/biosynthesis , Prenatal Exposure Delayed Effects , Scavenger Receptors, Class B/metabolism , Adrenal Glands/anatomy & histology , Adrenal Glands/enzymology , Adrenal Glands/metabolism , Adrenocorticotropic Hormone/blood , Animals , Cholesterol/blood , Cholesterol/metabolism , Corticosterone/blood , Female , Fetal Growth Retardation , Growth/drug effects , Hydroxymethylglutaryl CoA Reductases/metabolism , Lipopolysaccharides/toxicity , Male , Pregnancy , Rats , Rats, Wistar
14.
Oncotarget ; 8(55): 93741-93756, 2017 Nov 07.
Article En | MEDLINE | ID: mdl-29212186

This study aimed to investigate the effects of prenatal nicotine exposure (PNE) on thymocyte apoptosis and postnatal immune impairments in vivo and further explore the epigenetic mechanisms of the pro-apoptotic effect of nicotine in vitro. The results showed that PNE caused immune impairments in offspring on postnatal day 49, manifested as increased IL-4 production and an increased IgG1/IgG2a ratio in serum. Enhanced apoptosis of total and CD4+SP thymocytes was observed both in fetus and in offspring. Further, by exposing thymocytes to 0-100 µM of nicotine in vitro for 48 h, we found that nicotine increased α7 nicotinic acetylcholine receptor (nAChR) expression, activated the Fas apoptotic pathway, and promoted thymocyte apoptosis in concentration-dependent manners. In addition, nicotine could induce Tet methylcytosine dioxygenase (TET) 2 expression and Fas promoter demethylation, which can be abolished by TET2 siRNA transfection. Moreover, the α7 nAChR specific antagonist α-bungarotoxin can abrogate nicotine-induced TET2 increase, and the following Fas demethylation and Fas-mediated apoptosis. In conclusion, our findings showed, for the first time, that α7 nAChR activation could induce TET2-mediated Fas demethylation in thymocytes and results in the upregulation of Fas apoptotic pathway, which provide evidence for elucidating the PNE-induced programmed thymocyte apoptosis.

15.
Oncotarget ; 8(56): 96139-96153, 2017 Nov 10.
Article En | MEDLINE | ID: mdl-29221193

Intrauterine growth retardation (IUGR) is a common obstetric complication lacking an optimal method for prenatal screening. DNA methylation profile in maternal blood holds significant promise for prenatal screening. Here, we aimed to screen out potential IUGR biomarkers in maternal blood from the perspective of DNA methylation. The IUGR rat model was established by prenatal maternal undernutrition. High-throughput bisulfite sequencing of genomic DNA methylation followed by functional clustering analysis for differentially methylated region (DMR)-associated genes demonstrated that genes regulating transcription had the most significantly changed DNA methylation status in maternal blood with IUGR. Genes about apoptosis and placental development were also changed. Besides increased placental apoptosis, IUGR rats demonstrated the same hypermethylated CpG sites of steroidogenic factor-1 (SF-1, a DMR-associated transcription factor about placenta) promoter in maternal blood and placentae. Further, ff1b, the SF-1 ortholog, was knocked out in zebrafish by CRISPR/Cas9 technology. The knock-out zebrafish demonstrated developmental inhibition and increased IUGR rates, which confirmed the role of SF-1 in IUGR development. Finally, hypermethylated SF-1 was observed in human maternal blood of IUGR. This study firstly presented distinct DNA methylation profile in maternal blood of IUGR and showed hypermethylated SF-1 could be a potential IUGR biomarker in maternal rat blood.

16.
Sci Rep ; 7(1): 13746, 2017 10 23.
Article En | MEDLINE | ID: mdl-29062003

Our previous study showed that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR) and glucocorticoid elevation in the fetus. Researchers suggested that IUGR is a risk factor for T helper cell (Th)1/Th2 deviation. However, whether PCE can induce these immune disorders and the underlying mechanisms of that induction remain unknown. This study aimed to observe the effects of PCE on the Th1/Th2 balance in offspring and further explore the developmental origin mechanisms from the perspective of glucocorticoid overexposure-induced thymocyte apoptosis. An IUGR model was established by caffeine administration from gestational day (GD) 9 to GD 18, and the offspring were immunized on postnatal day (PND) 42. The results show that maternal glucocorticoid overexposure increased fetal thymocyte apoptosis by activating both the Fas-mediated and the Bim-regulated apoptotic pathways. After birth, accelerated thymocyte apoptosis and Th1 suppression were also found in the PCE offspring at PND 14 and PND 49. Moreover, the PCE offspring showed immune disorders after immunization, manifesting as increased IgG1/IgG2a ratio and IL-4 production in the serum. In conclusion, PCE could induce fetal overexposure to maternal glucocorticoids and increase thymocyte apoptosis, which could persist into postnatal life and be implicated in Th1 inhibition and further immune disorders.


Apoptosis/drug effects , Apoptosis/immunology , Caffeine/adverse effects , Glucocorticoids/metabolism , Maternal Exposure/adverse effects , Thymocytes/cytology , Thymocytes/drug effects , Animals , Cell Count , Cytokines/metabolism , Female , Fetus/immunology , Fetus/metabolism , Glucocorticoids/blood , Mice , Mice, Inbred BALB C , Phenotype , Pregnancy , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction/drug effects , Signal Transduction/immunology , Th1 Cells/cytology , Th1 Cells/drug effects , Th2 Cells/cytology , Th2 Cells/drug effects , Thymocytes/immunology , Up-Regulation/drug effects , Up-Regulation/immunology
17.
Reprod Toxicol ; 74: 212-218, 2017 12.
Article En | MEDLINE | ID: mdl-29055810

This study aimed to investigate the association between prenatal caffeine ingestion (PCI) and risk of postnatal pulmonary inflammation. Pregnant Wistar rats were administered 60mg/kg/d caffeine intragastrically from gestational day (GD) 7 to GD 20. The results showed that PCI obviously increased intrauterine growth retardation rate to 39.2% and suppressed weight growth of the offspring. PCI also enhanced the expression of transforming growth factor ß, α-smooth muscle actin, interleukin (IL)-1ß, and IL-8 in lungs and caused pulmonary interstitial thickening in the offspring. Further, with lipopolysaccharide stimulation on postnatal day 77, PCI offspring showed more serious inflammatory infiltration, higher injury scores, and higher levels of IL-6 and tumor necrosis factor-α in lungs than those of the control. Our findings showed, for the first time, that PCI is a certainly threat to postnatal pulmonary inflammation. The potential mechanism is that PCI alter the expression of pulmonary interstitial thickening-associated genes in the offspring.


Caffeine/toxicity , Inflammation/chemically induced , Lung/drug effects , Prenatal Exposure Delayed Effects , Animals , Cytokines/genetics , Cytokines/immunology , Female , Fetal Growth Retardation/chemically induced , Inflammation/genetics , Inflammation/immunology , Inflammation/pathology , Lung/immunology , Lung/pathology , Pregnancy , Rats, Wistar
18.
Environ Toxicol Pharmacol ; 56: 50-55, 2017 Dec.
Article En | MEDLINE | ID: mdl-28886425

This study was designed to observe the effects of maternal food restriction (MFR) on the development of fetal thymus in different gestation periods. Timed pregnant rats were randomized into 3 groups: CN (free access to standard chow throughout gestation), MFR0-21 (50% MFR throughout gestation), MFR0-14 (50% MFR from gestational day (GD) 0 to GD14, early-mid gestation). Results showed that MFR during early-mid period had few impact on the fetal thymus and T cell subpopulations. However, MFR throughout gestation resulted in thymic atrophy, deceased frequency of both CD4+ and CD8+ single positive (SP) T cells and enhanced thymocyte apoptosis in fetus. Our results suggest the fetal thymus is more vulnerable to the adverse intrauterine environments in the late gestation period, and the decreased number of SP T cells could result from the enhanced thymocyte apoptosis.


Malnutrition/complications , T-Lymphocytes/cytology , Thymocytes/cytology , Thymus Gland/immunology , Animals , Apoptosis , CD4-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/cytology , Female , Gestational Age , Lymphocyte Count , Malnutrition/immunology , Maternal-Fetal Exchange , Pregnancy , Rats , Rats, Wistar
19.
Pediatr Res ; 82(4): 704-711, 2017 Oct.
Article En | MEDLINE | ID: mdl-28604758

BackgroundEmerging evidence suggests that DNA methylation in maternal blood is a promising target for intrauterine growth retardation (IUGR) screening, a common developmental toxicity. Here, we aimed to screen out IUGR-related DNA methylation status in maternal blood via high-throughput profiling.MethodsPregnant Wistar rats were subcutaneously administered nicotine (1 mg/kg) twice per day from gestational day (GD) 11 to GD20 to establish the IUGR model. MeDIP array assays and the following GO analysis were used to evaluate DNA methylation status in maternal blood. One placental development-associated gene was selected for further confirmation.ResultsGenes regulating the development of multiple organs and major body systems had changed DNA methylation frequencies in the maternal blood of IUGR rats. Placental development, which can affect the development of multiple fetal organs and induce IUGR, is a hypermethylated cluster consisting of four significantly changed genes, including syncytin b (Synb), Lrrc15, Met, and Tex19.1. With the most significant change, Synb hypermethylation in maternal blood was confirmed by bisulfite-sequencing PCR (BSP). Moreover, decreased Synb expression and histological changes were observed in IUGR placentae.ConclusionThe IUGR-associated DNA methylation profile in maternal blood, such as placenta-related Synb hypermethylation, provides evidence for further studies on possible IUGR biomarkers.


DNA Methylation , Epigenesis, Genetic , Fetal Growth Retardation/genetics , Oligonucleotide Array Sequence Analysis , Pregnancy Proteins/genetics , Animals , Disease Models, Animal , Female , Fetal Growth Retardation/blood , Fetal Growth Retardation/chemically induced , Gene Expression Regulation, Developmental , High-Throughput Nucleotide Sequencing , Nicotine , Placenta/metabolism , Pregnancy , Pregnancy Proteins/blood , Promoter Regions, Genetic , Rats, Wistar
20.
Curr Drug Targets ; 18(10): 1132-1141, 2017.
Article En | MEDLINE | ID: mdl-27890000

Immunity is a balanced status with adequate biological defenses to recognize and fight "non-self", as well as adequate tolerance to recognize "self". To maintain this immune homeostasis, a well-organized T cell immune network is required, which in part depends on the well-controlled development of alternative effector T cells, with different cytokine repertoires. Recent researches have pointed that developing fetal T cells network is a remarkably sensitive toxicological target for adverse factors in early life. Epidemiological and experimental studies showed an inseparable relationship between T cell developmental toxicity and immune diseases in adults. Considering that the inflammatory and immune disorders have become a growing health problem worldwide, increasing attention is now being paid to the T cell developmental toxicity. We propose that adverse factors may have programming effects on the crucial functions of immune system during early life which is critical for fetal T cell development and the establishment of the distinct T cell repertoires balance. The permanently disturbed intrathymic or peripheral T cell development may in turn lead to the immune disorders in later life. In this manuscript, we reviewed how adverse factors affected T cell development in early-life with the consequence of the immune dysfunction and immune diseases, and further elucidate the mechanisms. These mechanisms will be helpful in prevention and treatment of the increased prevalence of immune diseases by interfering those pathways.


Fetal Development , Immune Tolerance , T-Lymphocytes/immunology , Animals , Cytokines/metabolism , Humans , Immunity, Innate
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