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1.
Nat Immunol ; 19(8): 859-870, 2018 08.
Article in English | MEDLINE | ID: mdl-30013146

ABSTRACT

IgE is an ancient and conserved immunoglobulin isotype with potent immunological function. Nevertheless, the regulation of IgE responses remains an enigma, and evidence of a role for IgE in host defense is limited. Here we report that topical exposure to a common environmental DNA-damaging xenobiotic initiated stress surveillance by γδTCR+ intraepithelial lymphocytes that resulted in class switching to IgE in B cells and the accumulation of autoreactive IgE. High-throughput antibody sequencing revealed that γδ T cells shaped the IgE repertoire by supporting specific variable-diversity-joining (VDJ) rearrangements with unique characteristics of the complementarity-determining region CDRH3. This endogenous IgE response, via the IgE receptor FcεRI, provided protection against epithelial carcinogenesis, and expression of the gene encoding FcεRI in human squamous-cell carcinoma correlated with good disease prognosis. These data indicate a joint role for immunosurveillance by T cells and by B cells in epithelial tissues and suggest that IgE is part of the host defense against epithelial damage and tumor development.


Subject(s)
B-Lymphocytes/physiology , Carcinoma, Squamous Cell/immunology , Epithelial Cells/physiology , Immunoglobulin E/metabolism , Intraepithelial Lymphocytes/physiology , Neoplasms, Experimental/immunology , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Receptors, IgE/metabolism , Animals , Anthracenes/toxicity , Carcinoma, Squamous Cell/diagnosis , Cell Death , Cells, Cultured , Complementarity Determining Regions/genetics , DNA Damage , Female , High-Throughput Nucleotide Sequencing , Immunoglobulin Class Switching , Immunoglobulin E/genetics , Immunologic Surveillance , Mice , Mice, Inbred C57BL , Mice, Knockout , Neoplasms, Experimental/chemically induced , Piperidines/toxicity , Prognosis , Receptors, Antigen, T-Cell, gamma-delta/genetics
2.
Environ Sci Technol ; 58(27): 11923-11934, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38918172

ABSTRACT

Chlorinated anthracenes (Cl-Ants), persistent organic pollutants, are widely detected in the environment, posing potential lung toxicity risks due to frequent respiratory exposure. However, direct evidence and a comprehensive understanding of their toxicity mechanisms are lacking. Building on our prior findings of Cl-Ants' immunotoxic risks, this study developed a three-dimensional coculture spheroid model mimicking the lung's immune microenvironment. The objective is to explore the pulmonary immunotoxicity and comprehend its mechanisms, taking into account the heightened immune reactivity and frequent lung exposure of Cl-Ants. The results demonstrated that Cl-Ants exposure led to reduced spheroid size, increased macrophage migration outward, lowered cell viability, elevated 8-OHdG levels, disturbed anti-infection balance, and altered cytokine production. Specifically, the chlorine substituent number correlates with the extent of disruption of spheroid indicators caused by Cl-Ants, with stronger immunotoxic effects observed in dichlorinated Ant compared to those in monochlorinated Ant. Furthermore, we identified critical regulatory genes associated with cell viability (ALDOC and ALDOA), bacterial response (TLR5 and MAP2K6), and GM-CSF production (CEBPB). Overall, this study offers initial in vitro evidence of low-dose Cl-PAHs' pulmonary immunotoxicity, advancing the understanding of Cl-Ants' structure-related toxicity and improving external toxicity assessment methods for environmental pollutants, which holds significance for future monitoring and evaluation.


Subject(s)
Lung , Lung/drug effects , Anthracenes/toxicity , Humans , Coculture Techniques , Cell Survival/drug effects
3.
Ecotoxicology ; 33(7): 737-749, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38981940

ABSTRACT

Anthracene (Anth) and pyrene (Pyr), two of the priority polycyclic aromatic hydrocarbons (PAHs), being lipophilic in nature, not only accumulate in animals, but also settle in the sediment of water bodies leading to continuous exposure for animals. Anth and Pyr when exposed to sunlight can be photoactivated and have harmful effects on aquatic organisms. A comparative analysis was carried out to assess the acute, sub-chronic, genetic and biochemical toxicity of Anth and Pyr in F. limnocharis tadpoles following short exposures to sunlight on a daily basis. In the bioaccumulation studies, it was found that both Anth and Pyr accumulated in the tadpole tissues in a concentration and time dependent manner. The LC50 values for Anth (under 15 min of daily sunlight exposure) were found to be 2.87, 2.59, 2.28, 1.80 mg/L at 24, 48, 72 and 96 h of the exposures. The corresponding LC50 values for Pyr were 1.03, 0.80, 0.62, 0.42 mg/L. Sublethal exposure of Anth and Pyr affected the survivality, time to metamorphosis as well as morphometric parameters under sunlight exposure. In the genotoxicity assessment studies, particularly the micronucleus test and comet assay, it was found that Pyr led to a higher incidence of micronucleus formation and DNA damage in comparison to Anth. The exposure to PAHs resulted in significant changes in the activity of antioxidant-mediated protective response, specifically the SOD activity, which varied between the groups treated with Anth and Pyr. On the other hand, Pyr treated group showed a higher level of GSH as compared to Anth treated groups. Moreover, the elevation in MDA level in the Anth and Pyr treated groups suggests an increase in lipid peroxidation. Future research should focus on understanding the ecotoxicological risk faced by anuran amphibia due to PAHs that frequently occur in aquatic environments and developing strategies to mitigate these risks.


Subject(s)
Anthracenes , Larva , Pyrenes , Water Pollutants, Chemical , Animals , Pyrenes/toxicity , Larva/drug effects , Anthracenes/toxicity , Water Pollutants, Chemical/toxicity , Anura
4.
Environ Geochem Health ; 46(2): 61, 2024 Jan 28.
Article in English | MEDLINE | ID: mdl-38281271

ABSTRACT

The objective of this study was to investigate the effects of anthracene (Ant) with 3 rings, benzo[a]anthracene (BaA) with 4 rings and benzo[b]fluoranthene (BbF) with 5 rings in fine particulate matter (PM2.5) at different exposure times (4 h and 24 h) and low exposure levels (0 pg/mL, 0.1 pg/mL, 1 pg/mL, 100 pg/mL and 10,000 pg/mL) on RAW264.7 cells. The changes of interleukin-6 (IL-6) and oxidative stress levels in RAW264.7 cells were investigated by methyl-thiazolyl-tetrazolium (MTT) and enzyme-linked immunosorbent assay (ELISA). Pearson correlation analysis was used to analyze the correlation between variables. Ant, BaA and BbF induced the secretion of IL-6 and the occurrence of oxidative stress in RAW264.7 cells. The inflammatory effect and oxidative damage were exacerbated with prolonged exposure time, increasing exposure concentration and increasing number of PAH rings. At the same time, IL-6 was found to have a certain correlation with the levels of ROS, MDA and SOD. Exposure to atmospheric PAHs at low concentrations can also produce toxic effects on cells, IL-6 and oxidative stress work together in cell damage. The study is expected to provide a theoretical and experimental basis for air pollution control and human health promotion.


Subject(s)
Air Pollutants , Polycyclic Aromatic Hydrocarbons , Air Pollutants/toxicity , Anthracenes/toxicity , Interleukin-6 , Macrophages/chemistry , Oxidative Stress , Particulate Matter/toxicity , Polycyclic Aromatic Hydrocarbons/toxicity , Animals , Mice , RAW 264.7 Cells
5.
Chem Res Toxicol ; 36(7): 1002-1020, 2023 07 17.
Article in English | MEDLINE | ID: mdl-37347986

ABSTRACT

Unraveling the causes underlying polycyclic aromatic hydrocarbon phototoxicity is an essential step in understanding the harmful effects of these compounds in nature. Toward this end, we have studied the DNA interactions and photochemistry of N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride in the presence and absence of NaF, KF, NaCl, KCl, NaBr, KBr, NaI, and KI (350 nm hν, pH 7.0). Exposing pUC19 plasmid to UV light in solutions containing 400 mM KCl formed significantly more direct strand breaks in DNA compared to no-salt control reactions. In contrast, NaCl increased DNA damage moderately, while the sodium(I) and potassium(I) fluoride, bromide, and iodide salts generally inhibited cleavage (I- > Br- > F-). A halide anion-induced heavy-atom effect was indicated by monitoring anthracene photodegradation and by employing the hydroxyl radical (•OH) probe hydroxyphenyl fluorescein (HPF). These studies revealed that among no-salt controls and the eight halide salts, only NaCl and KCl enabled the anthracene to photosensitize the production of high levels of DNA-damaging reactive oxygen species (ROS). Pre-irradiation of N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride at 350 nm increased the amounts of chloride salt-induced •OH detected by HPF in subsequent anthracene photoactivation experiments. Taking into consideration that •OH and other highly reactive ROS are extremely short-lived, this result suggests that the pre-irradiation step might lead to the formation of oxidized anthracene photoproducts that are exceedingly redox-active. The fluorometric probes HPF and Singlet Oxygen Sensor Green revealed that KCl concentrations ranging from 150 to 400 mM and from 100 to 400 mM, respectively, enhanced N1-(anthracen-9-ylmethyl)ethane-1,2-diaminium dichloride photosensitized •OH and singlet oxygen (1O2) production over no-salt controls. Considering the relatively high levels of Na+, K+, and Cl- ions that exist in the environment and in living organisms, our findings may be relevant to the phototoxic effects exhibited by anthracenes and other polycyclic hydrocarbons in vivo.


Subject(s)
Chlorides , Dermatitis, Phototoxic , Humans , Sodium Chloride/pharmacology , Singlet Oxygen/metabolism , Reactive Oxygen Species , Salts/pharmacology , Anthracenes/toxicity , Anthracenes/chemistry , DNA
6.
Drug Chem Toxicol ; 45(3): 1302-1307, 2022 May.
Article in English | MEDLINE | ID: mdl-33050761

ABSTRACT

This study evaluated the cytotoxic, genotoxic, and the modulatory effects on DNA damage of hypericin in Chinese hamster lung fibroblasts (V79 cells). The hypericin is a natural polycyclic quinone, mainly extracted from St. John's Wort (Hypericum perforatum L.). Along with hyperforin, the hypericins are responsible for the antidepressant activity of St. John's Wort. Cytotoxicity was assessed by the XTT colorimetric assay and the nuclear division index (NDI). The genotoxic activity was studied by the micronucleus test at concentrations of 30, 60, 120, and 240 µg/mL. Mutagenic agents, methyl methanesulfonate (MMS, 44 µg/mL), doxorubicin (DXR, 0.5 µg/mL), and etoposide (VP16, 1 µg/mL) were used in combination with different concentrations of hypericin in order to evaluate the modulatory effect on DNA damage. Results showed that the hypericin was cytotoxic at concentrations above 156.2 µg/mL and genotoxic above 120 µg/mL. The hypericin significantly reduced DNA damage frequency induced by DXR, at concentrations of 30 and 60 µg/mL, and MMS at a concentration of 30 µg/mL, but was unable to reduce damage when combined with VP-16. These results demonstrate the non-photoactivated hypericin toxicological safety limits, its protective effect on DNA damage and provide a basis for future studies that may characterize better its chemopreventive mechanism.


Subject(s)
Hypericum , Anthracenes/toxicity , DNA Damage , Mutagens/toxicity , Perylene/analogs & derivatives , Plant Extracts
7.
Environ Sci Technol ; 55(6): 3716-3726, 2021 03 16.
Article in English | MEDLINE | ID: mdl-33635628

ABSTRACT

Polycyclic aromatic hydrocarbon (PAH) contamination has raised great environmental concerns, while the effects of low-molecular-weight organic compounds (LMWOCs) on PAH photodegradation at amorphous silica (AS)/air interfaces have been largely ignored. In this study, the phototransformation of anthracene (ANT) at amorphous silica (AS)/air interfaces was investigated with the addition of LMWOCs. ANT removal was attributed to •OH attacking and the energy transfer process via 3ANT*. Light irradiation induced the fractured ≡SiO• or ≡Si• generation on AS surfaces, which could react with absorbed H2O and O2 to generate •OH and further yield a series of hydroxylated products of ANT. The presence of citric acid and oxalic acid improved •OH generation and enhanced ANT removal by 1.0- and 2.2-fold, respectively. For comparison, the presence of catechol and hydroquinone significantly decreased ANT removal and produced coupling products. The results of density functional theory calculations suggest that persistent free radicals (PFRs) on AS surfaces from catechol or hydroquinone after •OH attacking prefer to cross-couple with ANT via C-C bonding rather than self-couple. Dianthrone and cross-coupling products might possess higher ecotoxicity, while hydroxylated products were less ecotoxic than their parent compounds based on Ecological Structure Activity Relationships (ECOSAR) estimation. The results of this study revealed the potential ecotoxicity of PAH-adsorbed particulates coexisting with LMWOCs and also provided a new insight into PAH transformation through PFR pathways.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Silicon Dioxide , Anthracenes/toxicity , Free Radicals , Photolysis , Polycyclic Aromatic Hydrocarbons/toxicity
8.
J Biochem Mol Toxicol ; 35(3): e22673, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33314472

ABSTRACT

Buccal mucosa carcinoma is a significant cause of death in developing nations. Vicenin-2 is a significant bioactive compound found in Ocimum sanctum Linn or Tulsi that possesses several pharmacologic properties. Our focus is to understand the possible impact of Vicenin-2 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters. Buccal carcinoma was induced by treatment with carcinogenic DMBA, three times a week for 14 weeks. We determined 100% tumor incidence, abnormal tumor volume, inclined tumor burden, and deduced body weight in DMBA-induced oral squamous cell carcinoma (OSCC) hamsters. The upregulation of cytokine levels (interleukin [IL]-6, IL-1ß, and tumor necrosis factor-alpha [TNF-α]) was observed in DMBA-induced OSCC hamsters. Moreover, dysplastic, hyperplastic, and squamous cell carcinoma was identified in the DMBA-induced OSCC hamsters. The diminished activities of lipid peroxidation and enzymatic/nonenzymatic antioxidants were observed in DMBA-induced hamsters. Furthermore, the high expression of proliferating cell nuclear antigen (PCNA), Cyclin-D1, and Bcl-2, and attenuated Bax expression were observed in DMBA-induced hamsters. Our study results explored that Vicenin-2 (30 mg/kg) treated with DMBA-brushed hamsters averted tumor incidence, improved the antioxidant status, and inhibited lipid peroxidation. Moreover, Vicenin-2 inhibited the immunohistochemical expression of PCNA, Cyclin-D1, and Bcl-2, and significantly restored apoptotic Bax levels. The Vicenin-2 treatment prevents the lesion formation in the oral epithelium of the DMBA-induced hamsters. The Vicenin-2 treatment potentially halts the proinflammatory cytokines (IL-6, IL-1ß, and TNF-α) production in OSCC hamsters. Thus, we proved that Vicenin-2 prevents DMBA-induced buccal carcinogenesis in hamsters via improving antioxidants by modulating apoptotic and cytokines signaling pathways.


Subject(s)
Anthracenes/toxicity , Antineoplastic Agents/pharmacology , Apigenin/pharmacology , Carcinoma, Squamous Cell , Glucosides/pharmacology , Mouth Mucosa/metabolism , Mouth Neoplasms , Animals , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/metabolism , Cricetinae , Mesocricetus , Mouth Neoplasms/chemistry , Mouth Neoplasms/metabolism
9.
Ecotoxicol Environ Saf ; 220: 112302, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34015631

ABSTRACT

Alkyl-PAHs are the predominant form of PAHs in crude oils which are supposed to demonstrate different toxicities compared to non-alkyl PAHs. Little information is available about the toxicity of alkyl-PAHs on marine Artemia. This study addressed and compared the lethal, behavioral, growth and developmental toxicities of three alkyl-PAHs, namely 3-methyl phenanthrene (3-mPhe), retene (Ret) and 2-methyl anthracene (2-mAnt), to their non-alkyl forms, phenanthrene (Phe) and anthracene (Ant) using Artemia parthenogenetica (nauplii, <24 h) as test organism following a 48 h and a 7 d of exposure, respectively. Benzo-a-pyrene (Bap) was selected as a reference toxicant for the comparison with the above alkyl-PAHs and non-alkyl PAHs. Results showed that for all tested endpoints, A. parthenogenetica nauplii had the highest sensitivity to Bap while Ant had no significant effect on nauplii survival or development within given concentrations. Considering the aqueous freely dissolved PAH concentrations, the 48 h-LC50 (survival), 48 h-EC50 (immobility) and 7 d-LC10 (survival) of Bap were calculated as 0.321, 0.285 and 0.027 µg/L, respectively, which were twofold to fivefold lower than those of Phe, 3-mPhe, Ret, Ant and 2-mAnt. A higher acute toxicity of alkyl-PAHs (3-mPhe and 2-mAnt) than their non-alkyl forms (Phe and Ant) was observed. Not limited to Phe, the common non-polar narcotic mode of action was also observed for Bap, 3-mPhe, Ret and 2-mAnt, which was evident by the inhibited mobility of nauplii. The decreased body lengths were found for all PAH treatments compared to the solvent control, whereas instar retardations were only found in nauplii exposed to Bap, Phe and Ret. Our findings emphasized the sensitivity differences of A. parthenogenetica nauplii to selected alkyl PAHs and non-alkyl PAHs and confirmed the application of lethal, behavioral and growth indicators in the toxicity evaluation of selected PAHs other than Ant. However, the distinct toxicities of these PAHs suggested other toxic modes of action may play more important roles apart from narcotic mode of action and need to be elucidated in future studies. In addition, a strong correlation between the body length and the instar of A. parthenogenetica nauplii was observed for each PAH exposure, suggesting that body length can be representative for both growth and developmental indicators during biological monitoring of PAH pollution in marine environment.


Subject(s)
Artemia/drug effects , Polycyclic Aromatic Hydrocarbons/toxicity , Water Pollutants, Chemical/toxicity , Animals , Anthracenes/toxicity , Artemia/growth & development , Artemia/physiology , Lethal Dose 50 , Phenanthrenes/toxicity
10.
Mol Carcinog ; 59(11): 1302-1316, 2020 11.
Article in English | MEDLINE | ID: mdl-33006223

ABSTRACT

Oral squamous cell carcinoma (OSCC) is a common malignant tumor of the head and neck. However, the molecular mechanism underlying its development and progression is yet unclear. Genes that are differentially expressed, that is, differentially expressed genes (DEGs), between normal and diseased tissues are believed to be involved in disease development and progression. To identify the DEGs in OSCC and explore their role in occurrence and progression, we established a Chinese hamster OSCC model, determined the DEG, screened the identified DEGs, and performed Gene Ontology (GO) and KEGG enrichment analyses. A protein-protein interaction (PPI) network was generated to screen potential candidate genes. We then analyzed the expression, tumor stage and prognosis of candidate genes using the Gene Expression Profiling Interactive Analysis (GEPIA) database. Finally, we verified the candidate DEGs by quantitative real-time PCR and Gene Expression Omnibus analysis. The results showed 194 significantly DEGs, 140 enriched GO terms, and 8 KEGG pathways, which suggested that OSCC was closely related to the immune system, cell migration, and extracellular matrix. GEPIA and PPI network analysis revealed that SPP1, TNC, and ACTA1 were significantly related to tumor staging; SPP1, tissue inhibitors of matrix metallopeptidases (MMPs) 1 (TIMP1), and ACTA1 were closely related to prognosis. The scores for the top five highest degree genes were close, and the TIMP1/MMP9 axis appeared to be at the center of the PPI network, indicating that expression changes in the TIMP1/MMP9 axis and related genes may be involved in tumor invasion and metastasis. These findings provide novel insights into the mechanism of oral cancer.


Subject(s)
Anthracenes/toxicity , Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/pathology , Computational Biology/methods , Disease Models, Animal , Matrix Metalloproteinase 9/metabolism , Mouth Neoplasms/pathology , Piperidines/toxicity , Tissue Inhibitor of Metalloproteinase-1/metabolism , Animals , Apoptosis , Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/metabolism , Cell Proliferation , Cricetinae , Cricetulus , Gene Expression Regulation, Neoplastic , Humans , Male , Matrix Metalloproteinase 9/genetics , Mice , Mouth Neoplasms/chemically induced , Mouth Neoplasms/metabolism , Prognosis , Tissue Inhibitor of Metalloproteinase-1/genetics , Tumor Cells, Cultured
11.
J Biochem Mol Toxicol ; 34(3): e22441, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31926054

ABSTRACT

Inflammation plays a vital role in the process of carcinogenesis and anti-inflammatory properties of phytochemicals are gaining more attention in the chemoprevention of cancer. The present study was designed to evaluate the anti-inflammatory potential of citronellol (CT) on 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in rats. The inflammation-associated gene and protein markers were analyzed by immunohistochemistry, reverse transcription polymerase chain reaction, and Western blot techniques. Markers such as nuclear factor-kB (NF-kB), tumor necrosis factor-α, interleukin-6 (IL-6), cyclooxygenase-2, macrophage inflammatory protein-1α, and inducible nitric oxide synthase are upregulated in DMBA-alone-treated mammary tumor tissues. The oral administration of CT (50 mg/kg BW) to DMBA-treated rats significantly downregulated the expression NF-kB and other inflammatory markers, and also increased the level of IL-10 in mammary tissues. The results suggested that the anti-inflammatory potential of CT prevented the incidence of chemical carcinogen-induced mammary cancer in rats.


Subject(s)
Acyclic Monoterpenes/pharmacology , Mammary Neoplasms, Experimental , NF-kappa B/metabolism , Neoplasm Proteins/metabolism , Signal Transduction/drug effects , Animals , Anthracenes/toxicity , Carcinogens/toxicity , Female , Mammary Neoplasms, Experimental/chemically induced , Mammary Neoplasms, Experimental/drug therapy , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Piperidines/toxicity , Rats , Rats, Sprague-Dawley
12.
Environ Toxicol ; 35(2): 203-212, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31714650

ABSTRACT

The incidence of type 1 diabetes (T1D) and its associated risks of chronic kidney disease or end-stage renal disease development are on the rise. T1D is an autoimmune disease in which insulin-producing beta cells are destroyed. Increased incidence of T1D has been suggested to be a result of environmental factors such as exposure to polycyclic aromatic hydrocarbons (PAHs). 2-aminoanthracene (2AA) is a PAH that has been associated with the onset of early diabetic symptoms. This study was conducted to assess if 2AA dietary ingestion would induce T1D renal injuries. To accomplish study goals, Sprague-Dawley rats were assigned into three 2AA dietary (0, 50, and 100 mg/kg-2AA) ingestion groups for 12 weeks. Animals were evaluated for various morphometric indices, clinical markers, and gene expression. The rats in the 100 mg/kg group lost 5% less weight than the other treatment groups and converted roughly 3% more of their food intake into body mass. Renal histopathology indicated no significant difference between groups. The kidney weight per bodyweight of the 100 mg/kg treatment group was 30.1% greater than the control group. Creatinine concentration of the 100 mg/kg group was 46.2% greater than the control group. Serum glucose levels were significantly elevated in rats exposed to 2AA. On the contrary, serum albumin concentration was significantly reduced in 2AA-treated rats. T1D and genetic markers of renal injury such as FABP1, SPP1, IL-1B, and IL-7 were elevated in treated groups. These results suggest that 2AA may induce the early diabetic renal injuries.


Subject(s)
Anthracenes/toxicity , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 1/metabolism , Kidney/drug effects , Animals , Biomarkers/blood , Blood Glucose/analysis , Creatinine/blood , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Type 1/blood , Fatty Acid-Binding Proteins/genetics , Kidney/metabolism , Kidney/pathology , Male , Organ Size/drug effects , Rats , Rats, Sprague-Dawley , Serum Albumin/analysis
13.
Int J Toxicol ; 39(5): 465-476, 2020.
Article in English | MEDLINE | ID: mdl-32588678

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) refer to a ubiquitous group of anthropogenic air pollutants that are generated through incomplete carbon combustion. Although the immunotoxic nature of PAHs has been previously reported, the underlying molecular mechanisms of this effect are not fully understood. In the present study, we investigated the mitochondrial-mediated epigenetic regulation of 2 PAHs, carcinogenic (benzo[a]pyrene; BaP) and noncarcinogenic (anthracene [ANT]), in peripheral lymphocytes. While ANT exposure triggered mitochondrial oxidative damage, no appreciable epigenetic modifications were observed. On the other hand, exposure to BaP perturbed the mitochondrial redox machinery and initiated cascade of epigenetic modifications. Cells exposed to BaP showed prominent changes in the expression of mitochondrial microRNAs (miR-24, miR-34a, miR-150, and miR-155) and their respective gene targets (NF-κß, MYC, and p53). The exposure of BaP also caused significant alterations in the expression of epigenetic modifiers (DNMT1, HDAC1, HDAC7, KDM3a, EZH2, and P300) and hypomethylation within nuclear and mitochondrial DNA. This further induced methylation of histone tails, which play a crucial role in the regulation of chromatin structure. Overall, our study provides novel mechanistic insights into the mitochondrial regulation of epigenetic modifications in association with PAH-induced immunotoxicity.


Subject(s)
Air Pollutants/toxicity , Anthracenes/toxicity , Benzo(a)pyrene/toxicity , Carcinogens/toxicity , Lymphocytes/drug effects , Mitochondria/drug effects , Apoptosis/drug effects , Cells, Cultured , DNA Damage , DNA Methylation/drug effects , Epigenesis, Genetic/drug effects , Histones/metabolism , Humans , Lymphocytes/metabolism , Lymphocytes/physiology , Membrane Potential, Mitochondrial/drug effects , MicroRNAs/metabolism , Mitochondria/metabolism , Mitochondria/physiology , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolism
14.
Article in English | MEDLINE | ID: mdl-33377427

ABSTRACT

Type 1 diabetes (T1D) is an autoimmune disorder caused by the destruction of insulin-secreting ß-cells.T1D is on the rise around the world. Exposure to polycyclic aromatic hydrocarbons (PAHs) including 2-aminoanthracene (2AA) is considered a contributor to TID increase. The contribution of the ingestion of 2AA toward T1D vulnerability is examined. 2AA is found in a variety of household products. Juvenile male Sprague Dawley rats ingested various amounts of 2AA contaminated diet for 12 weeks. Results showed marginal reduction in body weight gain for the 100 mg/kg treated animals. Glucose tolerance test (GTT) indicated no changes at six weeks. However, at week 12, both treated groups had higher levels of blood glucose than the control group. Serum insulin concentration was elevated in the 50 mg/kg group while reduced in the 100 mg/kg animals. Serum lactate dehydrogenase activity was elevated in treated groups. Evaluation of pancreatic inflammatory cytokines revealed overexpression of IL-1B, IL-6, and IL-7. Apoptotic genes in the pancreas of exposed rats were overly expressed. Histopathology and insulin immunohistochemistry data showed the presence of mesenteric vessels surrounded by lymphocyte and enlarged size of islet cells respectively in the high dose group. These results suggest 2AA ingestion may enhance T1D development.


Subject(s)
Anthracenes/toxicity , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Type 1/chemically induced , Dietary Exposure/analysis , Environmental Pollutants/toxicity , Animals , Apoptosis/drug effects , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/immunology , Insulin-Secreting Cells/pathology , Interleukins/genetics , Male , Rats , Rats, Sprague-Dawley , Risk
15.
Mol Carcinog ; 58(5): 722-734, 2019 05.
Article in English | MEDLINE | ID: mdl-30582219

ABSTRACT

Bioactive derivatives from the camphor laurel tree, Cinnamomum camphora, are posited to exhibit chemopreventive properties but the efficacy and mechanism of these natural products are not fully understood. We tested an essential-oil derivative, camphor white oil (CWO), for anti-tumor activity in a mouse model of keratinocyte-derived skin cancer. Daily topical treatment with CWO induced dramatic regression of pre-malignant skin tumors and a two-fold reduction in cutaneous squamous cell carcinomas. We next investigated underlying cellular and molecular mechanisms. In cultured keratinocytes, CWO stimulated calcium signaling, resulting in calcineurin-dependent activation of nuclear factor of activated T cells (NFAT). In vivo, CWO induced transcriptional changes in immune-related genes identified by RNA-sequencing, resulting in cytotoxic T cell-dependent tumor regression. Finally, we identified chemical constituents of CWO that recapitulated effects of the admixture. Together, these studies identify T cell-mediated tumor regression as a mechanism through which a plant-derived essential oil diminishes established tumor burden.


Subject(s)
Camphor/administration & dosage , Carcinoma, Squamous Cell/drug therapy , Keratinocytes/drug effects , Oils, Volatile/administration & dosage , Skin Neoplasms/drug therapy , T-Lymphocytes, Cytotoxic/immunology , Animals , Anthracenes/toxicity , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/immunology , Cell Proliferation , Cells, Cultured , Female , Humans , Keratinocytes/immunology , Keratinocytes/pathology , Mice , NFATC Transcription Factors/metabolism , Piperidines/toxicity , Skin Neoplasms/chemically induced , Skin Neoplasms/immunology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/metabolism
16.
Fish Shellfish Immunol ; 84: 656-663, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30393156

ABSTRACT

Previous research has indicated that the small compound, SP600125, could induce polyploidy of fish cells, and has established a stable tetraploid cell line from diploid fish cells. In order to explore how fish cells maintain homeostasis under SP600125-stress in vitro, this study investigates impacts of SP600125-stress on intracellular pathways, as well as on regulation of the cellular homeostasis feedback in fish cells. Transcriptomes are obtained from the SP600125-treated cells. Compared with unigenes expressed in control group (crucial carp fin cells), a total of 2670 and 1846 unigenes are significantly upregulated and downregulated in these cells, respectively. Differentially expressed genes are found, which are involved in innate defense, inflammatory pathways and cell adhesion molecules-related pathways. The SP600125-stress enhances cell-mediated immunity, characterized by significantly increasing expression of multiple immune genes. These enhanced immune genes include the pro-inflammatory cytokines (IL-1ß, TNF-ɑ, IL-6R), the adaptor signal transducers (STAT, IκBɑ), and the integrins (ɑ2ß1, ɑMß2). Furthermore, mitochondria are contributed to the cellular homeostasis regulation upon the SP600125-stress. The results show that acute inflammation is an adaptive and controlled response to the SP600125-stress, which is beneficial for alleviating toxicity by SP600125. They provide a potential way of breeding fish polyploidy induced by SP600125 in the future research.


Subject(s)
Anthracenes/toxicity , Carps/immunology , Cell Death/drug effects , Immunity, Innate/drug effects , Animals , Cell Line , Gene Expression Profiling/veterinary , Tetraploidy
17.
Toxicol Ind Health ; 35(9): 568-576, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31558114

ABSTRACT

Diabetes mellitus has been on a continual rise as one of the top chronic diseases to affect individuals worldwide. The goal of this study was to determine how exposure from a well-known toxicant, a polycyclic aromatic hydrocarbon called 2-aminoanthracene (2AA), could potentially lead to diabetes, damage the liver, and have negative effects to the offspring. Humans are exposed to 2AA from foods cooked in high heat and tobacco smoke, among others. To analyze the effects of 2AA, three groups of Sprague Dawley dams consumed an adulterated 2AA diet from gestation to their postnatal period. Timed-pregnant dams ingested 0 mg/kg (control group (C)), 50 mg/kg (low dose group (LD)), and 100 mg/kg (high dose group (HD)) 2AA. Hepatic gene expressions of Adam8, Bax, Ccng1, CD68, CD93, Cdkn1c, and Ddit4 indicated a significant overexpression of Bax, Ccng1, CD68, CD93, and Cdkn1c in treated groups. Although there was no significant difference in the damage to the liver architecture by 2AA, the positively stained CD68+ cells were slightly increased in treated rats. Significant decreases in the albumin and aspartate aminotransferase levels might indicate an inflammatory response from 2AA exposure in dams. Immunoglobulin A (IgA) concentration was also decreased, in contrast to studies of liver cirrhosis that reported increased serum IgA concentration. Overexpression of genes Ddit4, Cdkn1c, Ccng1, Bax, CD93, and CD68 point to hepatic inflammation and apoptosis. Overall results suggest a link between environmental 2AA exposure and adverse liver effects, which has potential to increase susceptibility to type 2 diabetes and other diseases.


Subject(s)
Anthracenes/toxicity , Chemical and Drug Induced Liver Injury/etiology , Lactation/drug effects , Liver/drug effects , Animals , Aspartate Aminotransferases/metabolism , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Female , Immunoglobulin A/blood , Liver/metabolism , Liver/pathology , Pregnancy/drug effects , Rats , Rats, Sprague-Dawley
18.
Breast Cancer Res ; 20(1): 99, 2018 08 30.
Article in English | MEDLINE | ID: mdl-30165877

ABSTRACT

BACKGROUND: While many studies have shown that maternal factors in pregnancy affect the cancer risk for offspring, few studies have investigated the impact of paternal exposures on their progeny's risk of this disease. Population studies generally show a U-shaped association between birthweight and breast cancer risk, with both high and low birthweight increasing the risk compared with average birthweight. Here, we investigated whether paternal malnutrition would modulate the birthweight and later breast cancer risk of daughters. METHODS: Male mice were fed AIN93G-based diets containing either 17.7% (control) or 8.9% (low-protein (LP)) energy from protein from 3 to 10 weeks of age. Males on either group were mated to females raised on a control diet. Female offspring from control and LP fathers were treated with 7,12-dimethylbenz[a]anthracene (DMBA) to initiate mammary carcinogenesis. Mature sperm from fathers and mammary tissue and tumors from female offspring were used for epigenetic and other molecular analyses. RESULTS: We found that paternal malnutrition reduces the birthweight of daughters and leads to epigenetic and metabolic reprogramming of their mammary tissue and tumors. Daughters of LP fathers have higher rates of mammary cancer, with tumors arising earlier and growing faster than in controls. The energy sensor, the AMP-activated protein kinase (AMPK) pathway, is suppressed in both mammary glands and tumors of LP daughters, with consequent activation of mammalian target of rapamycin (mTOR) signaling. Furthermore, LP mammary tumors show altered amino-acid metabolism with increased glutamine utilization. These changes are linked to alterations in noncoding RNAs regulating those pathways in mammary glands and tumors. Importantly, we detect alterations in some of the same microRNAs/target genes found in our animal model in breast tumors of women from populations where low birthweight is prevalent. CONCLUSIONS: Our study suggests that ancestral paternal malnutrition plays a role in programming offspring cancer risk and phenotype by likely providing a metabolic advantage to cancer cells.


Subject(s)
Birth Weight , Cell Transformation, Neoplastic/metabolism , Malnutrition/metabolism , Mammary Neoplasms, Experimental/epidemiology , Paternal Exposure/adverse effects , Animals , Animals, Newborn , Anthracenes/toxicity , Cell Transformation, Neoplastic/genetics , Diet, Protein-Restricted/adverse effects , Female , Gene Expression Regulation, Neoplastic , Humans , Incidence , Male , Malnutrition/etiology , Mammary Glands, Animal/metabolism , Mammary Glands, Animal/pathology , Mammary Neoplasms, Experimental/chemically induced , Mammary Neoplasms, Experimental/genetics , Mammary Neoplasms, Experimental/pathology , Metabolic Networks and Pathways , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , MicroRNAs/metabolism , Piperidines/toxicity , Pregnancy , Risk Assessment
19.
FASEB J ; 31(2): 526-543, 2017 02.
Article in English | MEDLINE | ID: mdl-27825106

ABSTRACT

The response of the skin to harmful environmental agents is shaped decisively by the status of the immune system. Keratinocytes constitutively express and secrete the chemokine-like mediator, macrophage migration inhibitory factor (MIF), more strongly than dermal fibroblasts, thereby creating a MIF gradient in skin. By using global and epidermis-restricted Mif-knockout (Mif-/- and K14-Cre+/tg; Miffl/fl) mice, we found that MIF both recruits and maintains antigen-presenting cells in the dermis/epidermis. The reduced presence of antigen-presenting cells in the absence of MIF was associated with accelerated and increased formation of nonmelanoma skin tumors during chemical carcinogenesis. Our results demonstrate that MIF is essential for maintaining innate immunity in skin. Loss of keratinocyte-derived MIF leads to a loss of control of epithelial skin tumor formation in chemical skin carcinogenesis, which highlights an unexpected tumor-suppressive activity of MIF in murine skin.-Brocks, T., Fedorchenko, O., Schliermann, N., Stein, A., Moll, U. M., Seegobin, S., Dewor, M., Hallek, M., Marquardt, Y., Fietkau, K., Heise, R., Huth, S., Pfister, H., Bernhagen, J., Bucala, R., Baron, J. M., Fingerle-Rowson, G. Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin.


Subject(s)
Macrophage Migration-Inhibitory Factors/metabolism , Skin Neoplasms/chemically induced , Skin/cytology , Skin/immunology , Animals , Anthracenes/toxicity , Antigens, CD/genetics , Antigens, CD/metabolism , Carcinogenesis , Gene Expression Regulation/physiology , Inflammation/metabolism , Keratinocytes/metabolism , Macrophage Migration-Inhibitory Factors/genetics , Mice , Mice, Inbred BALB C , Mice, Knockout , Mice, Transgenic , Piperidines/toxicity , Pyridines/toxicity , Receptors, CXCR/genetics , Receptors, CXCR/metabolism
20.
Cell Biol Toxicol ; 34(2): 143-162, 2018 04.
Article in English | MEDLINE | ID: mdl-28815372

ABSTRACT

A recent hypothesis suggesting that the pharmacological target TRPV1 (transient receptor potential vanilloid subfamily, member 1) may function as a tumour suppressor, which potentially impacts the development of TRPV1 antagonist therapeutics for a range of conditions. However, little is known about the long-term physiologic effects of TRPV1 blockade in the skin. In vitro and in vivo studies suggested that the potent TRPV1 competitive antagonist AMG-9810 promoted proliferation in N/TERT1 cells (telomerase-immortalised primary human keratinocytes 1) and tumour development in mouse skin that was mediated through EGFR/Akt/mTOR signalling. We attempted to reproduce the reported in vitro and in vivo findings to further explore this hypothesis to understand the underlying mechanism and the risk associated with TRPV1 antagonism in the skin. In vitro proliferation studies using multiple methods and topical application with AMG-9810 and structurally similar TRPV1 antagonists such as SB-705498 and PAC-14028 were performed. Although we confirmed expression of TRPV1 in primary human epidermal keratinocytes (HEKn) and spontaneously immortalised human keratinocytes (HaCaT), we were unable to demonstrate cell proliferation in either cell type or any clear evidence of increased expression of proteins in the EGFR/Akt/mTOR signalling pathway with these molecules. We were also unable to demonstrate skin tumour promotion or underlying molecular mechanisms involved in the EGFR/Akt/mTOR signalling pathway in a single-dose and two-stage carcinogenesis mouse study treated with TRPV1 antagonists. In conclusion, our data suggest that inhibiting the pharmacological function of TRPV1 in skin by specific antagonists has not been considered to be indicative of skin tumour development.


Subject(s)
Cell Proliferation/drug effects , Keratinocytes/drug effects , Skin Neoplasms/metabolism , TRPV Cation Channels/antagonists & inhibitors , Acrylamides/toxicity , Animals , Anthracenes/toxicity , Bridged Bicyclo Compounds, Heterocyclic/toxicity , Capsaicin/analogs & derivatives , Capsaicin/toxicity , Cell Line , Cell Survival/drug effects , Cocarcinogenesis , Female , Humans , Keratinocytes/metabolism , Keratinocytes/pathology , Mice , Mice, Hairless , Piperidines/toxicity , Primary Cell Culture , Pyridines/toxicity , Pyrrolidines/toxicity , Risk , Skin Neoplasms/pathology , TRPV Cation Channels/genetics , Urea/analogs & derivatives , Urea/toxicity
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