ABSTRACT
Dysregulated cholesterol metabolism represents an increasingly recognized feature of autism spectrum disorder (ASD). Children with fetal valproate syndrome caused by prenatal exposure to valproic acid (VPA), an anti-epileptic and mood-stabilizing drug, have a higher incidence of developing ASD. However, the role of VPA in cholesterol homeostasis in neurons and microglial cells remains unclear. Therefore, we examined the effect of VPA exposure on regulation of cholesterol homeostasis in the human microglial clone 3 (HMC3) cell line and the human neuroblastoma cell line SH-SY5Y. HMC3 and SH-SY5Y cells were each incubated in increasing concentrations of VPA, followed by quantification of mRNA and protein expression of cholesterol transporters and cholesterol metabolizing enzymes. Cholesterol efflux was evaluated using colorimetric assays. We found that VPA treatment in HMC3 cells significantly reduced ABCA1 mRNA, but increased ABCG1 and CD36 mRNA levels in a dose-dependent manner. However, ABCA1 and ABCG1 protein levels were reduced by VPA in HMC3. Furthermore, similar experiments in SH-SY5Y cells showed increased mRNA levels for ABCA1, ABCG1, CD36, and 27-hydroxylase with VPA treatment. VPA exposure significantly reduced protein levels of ABCA1 in a dose-dependent manner, but increased the ABCG1 protein level at the highest dose in SH-SY5Y cells. In addition, VPA treatment significantly increased cholesterol efflux in SH-SY5Y, but had no impact on efflux in HMC3. VPA differentially controls the expression of ABCA1 and ABCG1, but regulation at the transcriptional and translational levels are not consistent and changes in the expression of these genes do not correlate with cholesterol efflux in vitro.
Subject(s)
Autism Spectrum Disorder , Autistic Disorder , Neuroblastoma , Pregnancy , Female , Child , Humans , Valproic Acid/pharmacology , ATP Binding Cassette Transporter, Subfamily G, Member 1/genetics , Autism Spectrum Disorder/chemically induced , Autism Spectrum Disorder/drug therapy , Autism Spectrum Disorder/genetics , Cholesterol/metabolism , CD36 Antigens/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolismABSTRACT
Access to vaccines against SARS-CoV-2 virus was limited in poor countries during the COVID-19 pandemic. Therefore, a low-cost mRNA vaccine, PTX-COVID19-B, was produced and evaluated in a Phase 1 trial. PTX-COVID19-B encodes Spike protein D614G variant without the proline-proline (986-987) mutation present in other COVID-19 vaccines. The aim of the study was to evaluate safety, tolerability, and immunogenicity of PTX-COVID19-B vaccine in healthy seronegative adults 18-64 years old. The trial design was observer-blinded, randomized, placebo-controlled, and tested ascending doses of 16-µg, 40-µg, or 100-µg in a total of 60 subjects who received two intramuscular doses, 4 weeks apart. Participants were monitored for solicited and unsolicited adverse events after vaccination and were provided with a Diary Card and thermometer to report any reactogenicity during the trial. Blood samples were collected on baseline, days 8, 28, 42, 90, and 180 for serum analysis of total IgG anti-receptor binding domain (RBD)/Spike titers by ELISA, and neutralizing antibody titers by pseudovirus assay. Titers in BAU/mL were reported as geometric mean and 95% CI per cohort. After vaccination, few solicited adverse events were observed and were mild to moderate and self-resolved within 48 h. The most common solicited local and systemic adverse event was pain at the injection site, and headache, respectively. Seroconversion was observed in all vaccinated participants, who showed high antibody titers against RBD, Spike, and neutralizing activity against the Wuhan strain. Neutralizing antibody titers were also detected against Alpha, Beta, and Delta variants of concerns in a dose dependent manner. All tested doses of PTX-COVID19-B were safe, well-tolerated, and provided a strong immunogenicity response. The 40-µg dose showed fewer adverse reactions than the 100-µg dose, and therefore was selected for a Phase 2 trial, which is currently ongoing.Clinical Trial Registration number: NCT04765436 (21/02/2021). ( https://clinicaltrials.gov/ct2/show/NCT04765436 ).
Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Humans , Adolescent , Young Adult , Middle Aged , COVID-19 Vaccines/adverse effects , SARS-CoV-2/genetics , COVID-19/prevention & control , Pandemics/prevention & control , mRNA Vaccines , Antibodies, Neutralizing , Immunogenicity, Vaccine , Antibodies, Viral , Double-Blind MethodABSTRACT
Globally, â¼50 % of women smoke during pregnancy and the prevalence of vaping is increasing among women of reproductive age. However, the health effects of vaping during pregnancy are largely unknown. This study examined the effects of e-cig constituents alone and in combination (propylene glycol [PG], vegetable glycerin [VG], and nicotine) on human placental tissue viability (MTT assay) and immunoassayed levels of placenta-derived biomarkers, i.e., 8-isoprostane (8-IsoP), heme oxygenase-1 (HO-1), interleukin-6 (IL-6), ß-estradiol (E2), progesterone (P4), allopregnanolone (AP), and brain-derived neurotrophic factor (BDNF). Placental explant cultures were exposed ex vivo for 24 h to media-containing either nicotine (0-5000 nM), PG/VG (0-8 % v/v at 50/50 ratio), or a combination of both. No effects on tissue viability were observed at PG/VG concentrations < 8 % (v/v), while viability significantly reduced at PG/VG concentrations ≥ 10 % (v/v); biomarker studies employed only non-cytotoxic doses. Exposure to PG/VG decreased levels of 8-IsoP, IL-6, and E2, and treatment with 2 % or 8 % PG/VG significantly reduced HO-1 levels, compared to non-treated controls. Exposure to nicotine alone at 2,500 nM and 5,000 nM reduced MTT activity by 20 % (P = 0.04) and 70 % (P < 0.001), respectively, and significantly increased (P < 0.001) levels of HO-1 and BDNF, compared to controls. Treatment with nicotine alone and in combination with PG/VG reduced IL-6 and E2 levels. Interestingly, nicotine-induced toxicity was attenuated by PG/VG addition to nicotine-treated groups. These studies demonstrate that e-cig constituents negatively impact the human placenta and alters production of critical placental biomarkers, suggesting that vaping is an unsafe alternative for pregnant women or their unborn fetus.
Subject(s)
Electronic Nicotine Delivery Systems , Pregnancy , Female , Humans , Nicotine/adverse effects , Brain-Derived Neurotrophic Factor , Interleukin-6 , Placenta , Propylene Glycol/pharmacology , Glycerol/pharmacologyABSTRACT
Safe and effective vaccines are needed to end the COVID-19 pandemic. Here, we report the preclinical development of a lipid nanoparticleformulated SARS-CoV-2 mRNA vaccine, PTX-COVID19-B. PTX-COVID19-B was chosen among three candidates after the initial mouse vaccination results showed that it elicited the strongest neutralizing antibody response against SARS-CoV-2. Further tests in mice and hamsters indicated that PTX-COVID19-B induced robust humoral and cellular immune responses and completely protected the vaccinated animals from SARS-CoV-2 infection in the lung. Studies in hamsters also showed that PTX-COVID19-B protected the upper respiratory tract from SARS-CoV-2 infection. Mouse immune sera elicited by PTX-COVID19-B vaccination were able to neutralize SARS-CoV-2 variants of concern, including the Alpha, Beta, Gamma, and Delta lineages. No adverse effects were induced by PTX-COVID19-B in either mice or hamsters. Based on these results, PTX-COVID19-B was authorized by Health Canada to enter clinical trials in December 2020 with a phase 2 clinical trial ongoing.
Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Synthetic/immunology , mRNA Vaccines/immunology , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , CD4 Lymphocyte Count , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , COVID-19 Vaccines/adverse effects , Canada , Cell Line , Cricetinae , Drug Evaluation, Preclinical , Female , HEK293 Cells , Humans , Immunity, Cellular/immunology , Immunity, Humoral/immunology , Liposomes/pharmacology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Nanoparticles , Spike Glycoprotein, Coronavirus/genetics , Th1 Cells/immunologyABSTRACT
Cigarette smoke enhances placental inflammation and interferes with steroidogenesis. However, the chemicals in the smoke responsible for these biological activities are unclear. 2,6 xylidine (also called 2,6 Dimethylaniline, DMA) is a component of cigarette smoke that has carcinogenic properties but its effects on the placenta are unknown. Therefore, we hypothesized that DMA may interfere with placental steroidogenesis or enhance placental inflammation. Placental explant cultures were treated with 0-50,000 nM DMA and concentrations of progesterone (P4), estradiol (E2), testosterone (T), IL-1ß, TNF-α, IL-6, sgp130, HO-1, IL-10, 8-Isoprostane (8-IsoP), and BDNF in the conditioned medium were quantified. Since many environmental toxins enhance the proinflammatory host response to infection, we also performed experiments on placental cultures co-stimulated with 107 heat-killed E. coli. DMA alone significantly reduced P4 and T secretion but enhanced E2 secretion. The toxin also reduced placental secretion of IL-6, sgp130, and BDNF. For bacteria-stimulated cultures, DMA increased secretion of P4 and T, and proinflammatory cytokines (IL-1ß, TNF-α) but had mixed effects on anti-inflammatory markers, increasing some (sgp130, IL-10) and reducing others (HO-1). However, DMA enhanced 8-IsoP levels by bacteria-stimulated placental cultures, suggesting that it increases oxidative stress by the tissues. These studies suggest that DMA affects secretion of biomarkers by the placenta and may promote inflammation. Further studies are needed to determine if these observed changes occur in vivo and the extent to which DMA exposure increases the risk of adverse pregnancy outcomes associated with smoking in pregnancy.
Subject(s)
Placenta/metabolism , Aniline Compounds , Anti-Inflammatory Agents/pharmacology , Biomarkers/metabolism , Culture Media, Conditioned/metabolism , Cytokines/metabolism , Escherichia coli , Estradiol/metabolism , Female , Humans , Inflammation/metabolism , Interleukin-10/metabolism , Interleukin-1beta , Oxidative Stress , Pregnancy , Premature Birth/metabolism , Progesterone/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
INTRODUCTION: Post-partum depression (PPD) affects up to 19.1% of pregnancies and is associated with increased levels of proinflammatory cytokines, inflammation, and reductions in brain-derived neurotrophic factor (BDNF). Previous work by our team suggests that environmental toxins such as polybrominated diphenyl ethers (PBDEs) enhance placental inflammation and reduce BDNF production. Nearly, 100% of studied women in California have some level of exposure to these compounds due to extensive use of the flame retardants. High levels of exposure to PBDEs has been linked to increased risk of adverse pregnancy complications associated with placental inflammation such as preterm birth and gestational diabetes but their effects on risk of PPD is unclear. OBJECTIVE: To determine if PPD is associated with higher levels of PBDE-47, the most common PBDE congener in maternal plasma. METHODS: PBDE-47 was quantified in first trimester plasma samples collected from a cohort of 367 asymptomatic pregnant women that were routinely screened for depressive symptoms for 1 year post-partum. Data were analyzed using general linear models and multivariable logistic regression to determine if higher levels of PBDE-47 in the first trimester are associated with development of PPD. RESULTS: Women who developed PPD (n = 22) had significantly higher PBDE-47 levels in their plasma (p=.031) relative to those in which PPD was not diagnosed. Logistic regression analysis suggested that each two-fold increase in PBDE-47 concentrations increased the risk of PPD by 22% (OR = 1.22, 95% CI: 1.03, 1.47). Groups were similar regarding PTB rate, race-ethnicity, parity, child's sex, maternal pre-pregnancy obesity status, maternal age, family income, and study center. Results remained significant after adjustment for these possible confounding factors. CONCLUSIONS: These results suggest that PBDE-47 exposure in the first trimester is associated with increased risk of PPD.
Subject(s)
Depression, Postpartum , Premature Birth , Female , Humans , Infant, Newborn , Pregnancy , Brain-Derived Neurotrophic Factor , Depression, Postpartum/epidemiology , Depression, Postpartum/etiology , Halogenated Diphenyl Ethers/adverse effects , Inflammation , Maternal Exposure/adverse effects , Placenta , Premature Birth/chemically inducedABSTRACT
Recent studies suggest that women with high exposures to dibutyl phthalate (DBP) are at increased risk for preterm birth, a condition associated with aberrant inflammation in the placenta often caused by subclinical infections. Placental inflammation is also a risk factor for neurodevelopmental disorders whose risk may also be enhanced by DBP. It is unclear, however, if DBP enhances placental inflammation. Therefore, we studied the effects of DBP on the production of biomarkers of placental inflammation and neurodevelopment under basal conditions and a setting of mild infection. Placental explant cultures established from women undergoing elective caesarean delivery were treated with DBP with and without co-stimulation by 107 CFU/mL heat-killed E. coli for 24 h at 37 °C. Conditioned medium was harvested and concentrations of IL-1ß, TNF-α, IL-10, HO-1 and BDNF, a biomarker for neurodevelopment, were quantified. DBP significantly enhanced IL-6 production in basal cultures but had no significant on the other biomarkers quantified. Both TNF-α and IL-1ß production was enhanced by DBP for cultures co-stimulated with E. coli. Although marginal enhancement of IL-6, and IL-10 were observed for bacteria co-treated cultures, results were either non-monotonic or only approached statistical significance. HO-1 production tended to be reduced at the highest concentration of DBP tested and BDNF production was reduced by DBP in a dose-dependent manner for bacteria-stimulated cultures. These results suggest that DBP enhances basal IL-6 production but has little or no effect on other biomarkers studied. However, DBP enhances IL-1ß and TNF-α production but reduces BDNF production by bacteria-stimulated cultures.
Subject(s)
Dibutyl Phthalate/toxicity , Environmental Pollutants/toxicity , Placenta/immunology , Pregnancy Complications, Infectious/chemically induced , Brain-Derived Neurotrophic Factor/metabolism , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/immunology , Humans , Inflammation/chemically induced , Inflammation/immunology , Inflammation/pathology , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Placenta/drug effects , Placenta/metabolism , Placenta/pathology , Pregnancy , Pregnancy Complications, Infectious/immunology , Pregnancy Complications, Infectious/microbiology , Pregnancy Complications, Infectious/pathology , Primary Cell Culture/methods , Tumor Necrosis Factor-alpha/metabolismABSTRACT
The ability to switch a gene from off to on and monitor dynamic changes provides a powerful approach for probing gene function and elucidating causal regulatory relationships. Here, we developed and characterized YETI (Yeast Estradiol strains with Titratable Induction), a collection in which > 5,600 yeast genes are engineered for transcriptional inducibility with single-gene precision at their native loci and without plasmids. Each strain contains SGA screening markers and a unique barcode, enabling high-throughput genetics. We characterized YETI using growth phenotyping and BAR-seq screens, and we used a YETI allele to identify the regulon of Rof1, showing that it acts to repress transcription. We observed that strains with inducible essential genes that have low native expression can often grow without inducer. Analysis of data from eukaryotic and prokaryotic systems shows that native expression is a variable that can bias promoter-perturbing screens, including CRISPRi. We engineered a second expression system, Z3 EB42, that gives lower expression than Z3 EV, a feature enabling conditional activation and repression of lowly expressed essential genes that grow without inducer in the YETI library.
Subject(s)
Genes, Essential , Saccharomyces cerevisiae , Gene Library , Plasmids , Promoter Regions, Genetic , Saccharomyces cerevisiae/geneticsABSTRACT
Fluoxetine is commonly prescribed during pregnancy but developmental exposure to the drug, like infection, is associated with sex-specific behavioral changes in the offspring. We evaluated the effects of Fluoxetine on production of biomarkers for inflammation (pro/anti-inflammatory cytokines) and neurodevelopment (Brain-Derived Neurotrophic Factor, BDNF) in the presence and absence of infection in female and male placenta explant cultures. In addition to minor anti-inflammatory effects of the drug, Fluoxetine had significant sex- and infection-dependent effects on BDNF production. Further studies are needed to determine the extent to which these observed changes occur in vivo and their impact on pregnancy and neurodevelopmental outcomes.
Subject(s)
Fluoxetine/therapeutic use , Inflammation/metabolism , Placenta/drug effects , Biomarkers/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Cytokines/metabolism , Depressive Disorder/drug therapy , Female , Fluoxetine/administration & dosage , Humans , Male , Placenta/metabolism , PregnancyABSTRACT
OBJECTIVES: Nearly 100% of North American women have detectable levels of flame retardants such as polybrominated diphenyl ethers (PBDEs) in their plasma. These molecules have structural homology to thyroid hormones and may function as endocrine disruptors. Thyroid dysfunction has previously been associated with increased risk for preterm birth. Therefore, we conducted a multi-center, case-cohort study to evaluate if high plasma concentrations of a common PBDE congener in the first trimester increases the risk of preterm birth and its subtypes. METHODS: Pregnant women were recruited at the onset of initiation of prenatal care at Kaiser-Permanente Southern California (KPSC)-West Los Angeles and KPSC-San Diego medical centers. Plasma samples from women whose pregnancies ended preterm and random subset of those delivering at term were assayed for PBDE-47 and thyroid-stimulating hormone (TSH) by immunoassay. Quartile cutoffs were calculated for the patients at term and used to determine if women with exposures in the 4th quartile are at increased risk for preterm birth using logistic regression. RESULTS: We found that high concentrations of PBDE-47 in the first trimester significantly increased the odds of both indicated (adjusted odds ratio, adjOR=2.35, 95% confidence interval [CI]: 1.31, 4.21) and spontaneous (adjOR=1.76, 95% CI: 1.02, 3.03) preterm birth. Regardless of pregnancy outcome, TSH concentrations did not differ between women with high and low concentrations of PBDE-47. CONCLUSIONS: These results suggest that high plasma concentrations of PBDE-47 in the first trimester, increases the risk of indicated and spontaneous preterm birth.
Subject(s)
Halogenated Diphenyl Ethers , Pregnancy Trimester, First/blood , Premature Birth , Thyroid Diseases , Thyrotropin/blood , Adult , Cohort Studies , Endocrine Disruptors/adverse effects , Endocrine Disruptors/analysis , Endocrine Disruptors/blood , Female , Flame Retardants/adverse effects , Flame Retardants/analysis , Flame Retardants/metabolism , Halogenated Diphenyl Ethers/adverse effects , Halogenated Diphenyl Ethers/analysis , Halogenated Diphenyl Ethers/blood , Humans , Infant, Newborn , Pregnancy , Pregnancy Outcome/epidemiology , Premature Birth/epidemiology , Premature Birth/etiology , Premature Birth/prevention & control , Prenatal Care/methods , Prenatal Care/statistics & numerical data , Risk Assessment/methods , Risk Assessment/statistics & numerical data , Risk Factors , Thyroid Diseases/blood , Thyroid Diseases/chemically induced , Thyroid Diseases/complications , Thyroid Diseases/diagnosis , United States/epidemiologyABSTRACT
INTRODUCTION: Exosomes are intercellular signaling vesicles whose cargo reflects the physiological status of the cell of their origin and can regulate gene expression in other tissues. Polybrominated diphenyl ethers (PBDEs) and bisphenols (A [BPA], Tetrabromobisphenol A [TBBPA], and 2,4,6-Tribromophenol [TBP]) are common environmental pollutants known to increase the risk for spontaneous preterm birth (PTB). We hypothesized that placental exposure to these environmental pollutants causes exosome cargo changes that reflect exposure associated placental response. METHODS: Full-term, C-section placenta explants were treated with PBDE congeners (47, 100, 153, 209), TBBPA, TBP or BPA for 24â¯h. Exosomes were isolated from media by sequential ultracentrifugation and purified by size exclusion chromatography. Exosomes were characterized by electron microscopy, nanoparticle tracking analysis and Western blot. Proteomics identified differentially expressed exosomal proteins and Ingenuity pathway analysis (IPA) determined biological functions and pathways represented by identified proteins. RESULTS: Regardless of treatment, placental expressed exosomes markers (PLAP, CD9, CD63, 81 and ALIX), had a size distribution between 50 and 175â¯nm and were present in the conditioned medium at 5-8 x 1011 exosomes/mL. Proteomic analysis identified 2598 proteins which demonstrated that specific pollutants caused differential expression of specific proteins, including alarmin, High Mobility Group Box 1 (HMGB1), MAPK14 (p38 MAPK) and GSK3ß. IPA revealed an inhibition of pathways associated with cell survival, tissue repair and proliferation, as well as activation of cell death pathways (e.g. necrosis). CONCLUSION: Environmental exposure of placental explants did not change the quantity of exosomes or their characteristics. However, exosome cargo composition exposed to some environment pollutants may be involved in placental nuclear and cellular injury and inflammation.
Subject(s)
Benzhydryl Compounds/pharmacology , Environmental Pollutants/pharmacology , Exosomes/drug effects , Halogenated Diphenyl Ethers/pharmacology , Phenols/pharmacology , Placenta/drug effects , Polybrominated Biphenyls/pharmacology , Exosomes/metabolism , Female , Humans , Placenta/metabolism , PregnancyABSTRACT
Background Bisphenol-A (BPA) is a widespread pollutant whose effects on pregnant women are poorly understood. Therefore, we investigated the effects of BPA on basal and bacteria-stimulated production of proinflammatory cytokines [interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α) and IL-6], anti-inflammatory mediators [soluble glycoprotein 130 (sgp) 130, heme oxidase-1 (HO-1) and IL-10] and biomarkers for neurodevelopment [brain-derived neurotrophic factor (BDNF)], and oxidative stress [8-isoprostane (8-IsoP)] by the placenta. Methods Placental explant cultures were treated with BPA (0-10,000 nM) in the presence or absence of 107 colony-forming unit (CFU)/mL heat-killed Escherichia coli for 24 h. Biomarker concentrations in conditioned medium were quantified by the enzyme-linked immunosorbent assay (ELISA). Results Under basal conditions, IL-1ß and IL-6 production was enhanced by BPA in a dose-dependent manner. Sgp130, a soluble receptor that reduces IL-6 bioactivity, was suppressed by BPA at 1000-10,000 nM. BPA also enhanced BDNF production at 1000 and 10,000 nM, and 8-IsoP expression at 10 and 100 nM. For bacteria-treated cultures, BPA increased IL-6 production at 100 nM and reduced sgp130 at 1000 nM but had no effect on IL-1ß, TNF-α, BDNF, HO-1, 8-IsoP or IL-10 production. Conclusion BPA may increase placental inflammation by promoting IL-1ß and IL-6 but inhibiting sgp130. It may also disrupt oxidative balance and neurodevelopment by increasing 8-IsoP and BDNF production.
Subject(s)
Benzhydryl Compounds , Brain-Derived Neurotrophic Factor/metabolism , Cytokines , Escherichia coli/growth & development , Inflammation , Phenols , Placenta , Air Pollutants, Occupational/adverse effects , Air Pollutants, Occupational/metabolism , Benzhydryl Compounds/adverse effects , Benzhydryl Compounds/metabolism , Biomarkers/metabolism , Colony Count, Microbial/methods , Cytokines/classification , Cytokines/metabolism , Estrogens, Non-Steroidal/adverse effects , Estrogens, Non-Steroidal/metabolism , Female , Humans , Inflammation/chemically induced , Inflammation/metabolism , Oxidative Stress/drug effects , Phenols/adverse effects , Phenols/metabolism , Placenta/drug effects , Placenta/immunology , Placenta/metabolism , PregnancyABSTRACT
Placental inflammation increases the risk of adverse pregnancy outcomes and possibly neurodevelopmental disorders in the offspring. Previous research suggests it may be possible to modulate the placental immune response to bacteria to favor an anti-inflammatory phenotype with dietary factors. Sulforaphane (SFN) is a dietary supplement with known anti-inflammatory activities, however, its effects on placental cytokine production are unclear. Therefore, we evaluated the effects of SFN on biomarkers of inflammation and neurodevelopment under basal conditions and a setting of mild infection. Placental explant cultures were established and treated with up to 10 µM SFN in the presence and absence of 107 CFU/ml heat-killed E. coli. Concentrations of IL-1ß, TNF-α, IL-6, sgp130, HO-1 and BDNF in conditioned medium were quantified by immunoassay. SFN increased antioxidant HO-1 expression in the absence, but not the presence, of infection. SFN inhibited IL-1ß and IL-10, but tended to promote, TNF-α production by bacteria-stimulated cultures. IL-6 and BDNF were inhibited by SFN irrespective of co-treatment with E.coli. A negative regulator of IL-6 signaling, sgp130, was increased by SFN under basal conditions, but not in E. coli-stimulated cultures. These results suggest that SFN has mixed effects on the placenta inhibiting both pro-inflammatory (IL-1ß) and anti-inflammatory factors (IL-10) but promoting regulators of oxidative stress and inflammation (HO-1 and sgp130) in an infection-dependent manner.
Subject(s)
Cytokines/immunology , Isothiocyanates/pharmacology , Placenta/immunology , Pregnancy Proteins/immunology , Adult , Escherichia coli/immunology , Escherichia coli Infections/chemically induced , Escherichia coli Infections/immunology , Escherichia coli Infections/pathology , Female , Humans , Inflammation/chemically induced , Inflammation/immunology , Inflammation/pathology , Oxidative Stress/immunology , Placenta/microbiology , Placenta/pathology , Placenta Diseases/chemically induced , Placenta Diseases/immunology , Placenta Diseases/microbiology , Placenta Diseases/pathology , Pregnancy , SulfoxidesABSTRACT
PROBLEM: Placental infection induces increased levels of pro-inflammatory cytokines, which have been implicated in the pathogenesis of pre-term labor. Endotoxin tolerance is a phenomenon in which exposure to a dose of endotoxin makes tissue less responsive to subsequent exposures. The objective of our study was to determine whether repeated exposure to endotoxin will induce a tolerant phenotype in normal human second-trimester placental tissue. METHODS OF STUDY: Human second-trimester placental explants from elective termination of pregnancy were cultured and exposed to endotoxin (LPS). After 24 hours, the media was collected for analysis, and the explants were re-exposed to LPS after adding fresh media for another 24 hours. This process was repeated for a total of 4 LPS doses. The media was collected from each day and analyzed for cytokine levels. RESULTS: The first LPS treatment stimulated the secretion of the pro-inflammatory cytokines IL-1ß and TNF-α. However, their production was significantly diminished with repeated LPS doses. Production of the anti-inflammatory cytokines, IL-1ra and IL-10, was also stimulated by the first LPS treatment, but secretion was more gradually and moderately decreased with repeated LPS doses compared to the pro-inflammatory cytokines. The ratios of the anti-inflammatory/pro-inflammatory mediators (IL-1ra/IL-1ß and IL-10/TNF-α) indicate a progressively more anti-inflammatory milieu with repeated LPS doses. CONCLUSION: Repeated LPS exposure of human second-trimester placental tissues induced endotoxin tolerance. We speculate that endotoxin tolerance at the maternal-fetal interface will protect the fetus from exaggerated inflammatory responses after repeated infectious exposure.
Subject(s)
Endotoxins/immunology , Infections/immunology , Inflammation/immunology , Lipopolysaccharides/immunology , Obstetric Labor, Premature/prevention & control , Placenta/immunology , Pregnancy Complications/immunology , Cells, Cultured , Cytokines/metabolism , Female , Humans , Immune Tolerance , Immunomodulation , Maternal-Fetal Exchange , Organ Culture Techniques , Pregnancy , Pregnancy Trimester, SecondABSTRACT
OBJECTIVE: Polybrominated diphenyl ethers (PBDEs) enhance basal and bacteria-stimulated production of proinflammatory cytokines by the placenta and may also increase the risk of preterm birth and neurodevelopmental disorders. Whether or not other brominated flame retardants such as Tetrabromobisphenol A (TBBPA) have similar properties is unclear. Therefore, we evaluated the effects of TBBPA on the production of steroids, as well as biomarkers for inflammation, oxidative stress, and neurodevelopment by the placenta. METHODS: Placental explant cultures were established from women undergoing elective Cesarean sections at term and treated with 5-50,000â¯nM TBBPA in the presence and absence of 107â¯CFU/ml heat-killed E. coli. Concentrations of P4, E2, testosterone (T), IL-1ß, TNF-α, IL-10, HO-1, IL-6, 8-IsoP and BDNF were quantified in the conditioned medium. RESULTS: In the absence of bacteria, TBBPA tended to increase P4 and T as well as IL-6 and 8-IsoP. For bacteria-treated cultures, TBBPA generally inhibited P4, IL-1ß, and HO-1 production but enhanced TNF-α and IL-6 production. CONCLUSIONS: TBBPA alters placental steroidogenesis to favor T production and increases oxidative stress and placental inflammation as suggested by its promotion of 8-IsoP and IL-6 production. TBBPA may also function as a risk modifier where it enhances bacteria-stimulated production TNF-α and IL-6 but reduces HO-1 production, however, this was balanced by reductions in IL-1ß. Further studies are warranted to determine if TBBPA increases the risk of adverse pregnancy outcomes such as preterm birth, pPROM and neurodevelopmental disorders such as autism that have been associated with increased production of proinflammatory cytokines, oxidative stress and/or T.
Subject(s)
Inflammation/metabolism , Placenta/drug effects , Polybrominated Biphenyls/pharmacology , Biomarkers , Culture Media, Conditioned , Cytokines/metabolism , Estradiol/metabolism , Female , Humans , Placenta/metabolism , Pregnancy , Progesterone/metabolism , Term Birth , Testosterone/metabolismABSTRACT
Objective Tributyltin (TBT) is a persistent pollutant but its effects on placental function are poorly understood as are its possible interactions with infection. We hypothesized that TBT alters the production of sex hormones and biomarkers for inflammation and neurodevelopment in an infection-dependent manner. Methods Placental explant cultures were treated with 0-5000 nM TBT in the presence and absence of Escherichia coli. A conditioned medium was harvested and concentrations of steroids (progesterone, P4; testosterone, T and estradiol, E2) as well as biomarkers of inflammation [interleukin (IL)-1ß (IL-1ß), tumor necrosis factor (TNF-α), IL-10, IL-6, soluble glycoprotein 130 (sgp-130) and heme oxygenase-1 (HO-1)], oxidative stress [8-iso-prostaglandin (8-IsoP)] and neurodevelopment [brain-derived neurotrophic factor (BDNF)] were quantified. Results TBT increased P4 slightly but had little or no effect on T or E2 production. IL-1ß, IL-6, sgp-130, IL-10 and 8-IsoP production was enhanced by TBT. P4 and IL-6 production was also enhanced by TBT for bacteria-stimulated cultures but TBT significantly inhibited bacteria-induced IL-1ß and sgp-130 production. High doses of TBT also inhibited BDNF production. Conclusions TBT increases P4 but has minimal effect on downstream steroids. It enhances the production of inflammatory biomarkers such as IL-1ß, TNF-α, IL-10 and IL-6. Inhibition of sgp-130 by TBT suggests that TBT may increase bioactive IL-6 production which has been associated with adverse neurodevelopmental outcomes. Reduced expression of BDNF also supports this possibility.
Subject(s)
Cytokines/metabolism , Placenta/drug effects , Trialkyltin Compounds/toxicity , Culture Techniques , Escherichia coli , Female , Humans , Placenta/metabolism , PregnancyABSTRACT
Polybrominated diphenyl ethers (PBDEs) are pollutants that may increase the risk of preterm birth. In previous studies, we found that a mixture of PBDEs altered the expression of biomarkers for preterm birth by the placenta. However, there are 209 different PBDE congeners with different tissue distributions. How these different congeners may alter the production of immunomodulators by the placenta that help to maintain the survival of the fetal allograft is unclear. Therefore, we compared the effects 5 common congeners on basal and bacteria-stimulated cytokine production by the placenta. Placental explant cultures were incubated with 20⯵M of PBDE congeners 47, 99, 100, 153, 209 or vehicle in the presence and absence of Escherichia coli for 20â¯h. Conditioned medium was harvested and concentrations of IL-1ß, TNF-α, IL-6, sgp130, HO-1, IL-10, BDNF, and 8-IsoP quantified. For unstimulated cultures, all congeners, except for PBDE-47, reduced the production of IL-1ß and IL-6 production was enhanced by PBDE-153. BDNF concentrations tended to be reduced by most PBDE congeners and IL-10 production was enhanced by PBDE-99, -153, and -209. 8-IsoP production was enhanced by PBDE-153, but not the other congeners. For bacteria-stimulated cultures, PBDE-47 increased IL-1ß production and PBDE-47, -153, and -209 tended to reduce TNF-α production. IL-6 production was enhanced by all PBDEs except 153. IL-10 production was enhanced by all congeners except for PBDE-47. All congeners significantly enhanced BDNF and 8-IsoP. These results suggest that PBDEs can alter the expression of placental biomarkers in a congener and infection-dependent manner.
Subject(s)
Cytokines/metabolism , Environmental Pollutants/toxicity , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Placenta/drug effects , Biomarkers/metabolism , Cesarean Section , Culture Media, Conditioned/analysis , Culture Media, Conditioned/metabolism , Cytokines/analysis , Cytokines/immunology , Escherichia coli/immunology , Escherichia coli/pathogenicity , Female , Humans , Placenta/immunology , Placenta/metabolism , Pregnancy , Premature Birth/chemically induced , Premature Birth/immunology , Premature Birth/microbiology , Tissue Culture TechniquesABSTRACT
OATP1B1 and OATP1B3 (1B3) are members of organic anion-transporting polypeptides (OATPs), a family of sodium-independent organic anion membrane transporters that contribute to transport of various drugs. To identify peptide inhibitors of OATP1B1, we developed a direct selection system on live cells using phage-displayed peptide libraries. Selections against OATP1B1 overexpressed cell-lines yielded three unique peptides able to inhibit the transport function of OATP1B1 and 1B3. Affinity maturation of one peptide led to identification of two peptides that demonstrated improved inhibition efficacy on drug uptake mediated by OATP1B1 and 1B3. We anticipate that these peptides will assist the identification of novel substrates for OATP1B1 and 1B3. Moreover, our selection system is a practical method for generating inhibitors of other membrane transporters.
Subject(s)
Drug Discovery , Organic Anion Transporters, Sodium-Independent/antagonists & inhibitors , Organic Anion Transporters/antagonists & inhibitors , Peptide Library , Peptides/chemistry , Peptides/pharmacology , Amino Acid Sequence , Biological Transport/drug effects , HEK293 Cells , Humans , Liver-Specific Organic Anion Transporter 1 , Molecular Sequence Data , Organic Anion Transporters/metabolism , Organic Anion Transporters, Sodium-Independent/metabolism , Solute Carrier Organic Anion Transporter Family Member 1B3ABSTRACT
Roles of lipids in the cell membrane are poorly understood. This is partially due to the lack of methodologies, for example, tool chemicals that bind to specific membrane lipids and modulate membrane function. Theonellamides (TNMs), marine sponge-derived peptides, recognize 3ß-hydroxysterols in lipid membranes and induce major morphological changes in cultured mammalian cells through as yet unknown mechanisms. Here, we show that TNMs recognize cholesterol-containing liquid-disordered domains and induce phase separation in model lipid membranes. Modulation of membrane order was also observed in living cells following treatment with TNM-A, in which cells shrank considerably in a cholesterol-, cytoskeleton-, and energy-dependent manner. These findings present a previously unrecognized mode of action of membrane-targeting natural products. Meanwhile, we demonstrated the importance of membrane order, which is maintained by cholesterol, for proper cell morphogenesis.
Subject(s)
Cell Membrane/metabolism , Cholesterol/chemistry , Peptides, Cyclic/chemistry , Animals , Cell Line, Tumor , Cell Membrane/drug effects , Cell Shape/drug effects , Cholesterol/metabolism , Cytoskeleton/chemistry , Cytoskeleton/drug effects , Cytoskeleton/metabolism , Humans , Lipid Bilayers/chemistry , Lipid Bilayers/metabolism , Liposomes/chemistry , Liposomes/metabolism , Microscopy, Fluorescence , Peptides, Cyclic/isolation & purification , Peptides, Cyclic/pharmacology , Protein Binding , Theonella/metabolism , Tubulin/metabolismABSTRACT
Preterm birth is a leading cause of perinatal morbidity and mortality that is often associated with ascending infections from the lower genital tract. Recent studies with animal models have suggested that developmental exposure to the environmental toxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can increase the risk of preterm birth in the offspring. How TCDD may modify placental immunity to ascending infections is unclear. Therefore, we studied the effects of TCDD treatment on basal and Escherichia coli-stimulated cytokine production by placental explants. Cultures of second-trimester placentas were treated with up to 40 nM TCDD for 72 h and then stimulated with 10(7)CFU/ml E. coli for an additional 24h. Concentrations of cytokines and PGE2 were measured in conditioned medium by immunoassay. TCDD exposure increased mRNA levels of IL-1ß by unstimulated cultures, but no effects on protein levels of this cytokine were detected. TNF-α production was unaffected by TCDD for unstimulated cultures, but pre-treatment with 40 nM TCDD significantly increased E. coli-stimulated TNF-α production. Both basal and bacteria-stimulated PGE2 and COX-2 gene expression were enhanced by TCDD pretreatment. In contrast, production of the anti-inflammatory cytokine, IL-10, was reduced by TCDD pretreatment for both unstimulated and E. coli-stimulated cultures. No effect of TCDD on the viability of the cultures was detected. These results suggest that TCDD exposure may shift immunity to enhance a proinflammatory phenotype at the maternal-fetal interface that could increase the risk of infection-mediated preterm birth.