No abstract available.
Hematopoietic Stem Cells ; Receptors, Aryl Hydrocarbon

OBJECTIVETo explore the association between the arylhydrocarbon receptor gene (AhR) 1661G/A or arylhydrocarbon nuclear translocatorgene (ARNT) 567G/C polymorphism and endometriosis in southern Han Chinese women.

METHODSThe polymorphisms of AhR gene 1661G/Aand ARNT gene 567G/C in 431 cases of endometriosis and 499 healthy women were genotyped by fluorescence quantitative PCR-based high resolution melting.

RESULTSThe frequencies of genotypes AA, AG, GG and alleles A and G in controls were 12.0%, 41.9%, 46.1%, 33.0% and 67.0%, respectively, which were not significantly different from those in patients with endometriosis (9.7%, 44.6%, 45.7%, 32.0% and 68.0%, respectively). The genotype frequencies of GG, GC, CC and alleles C and G in controls (15.6 %, 51.7%, 32.7%, 58.5%, 41.5%) were not significantly different from those in patients with endometriosis (13.5%, 47.8%, 38.7%, 62.6%, 37.4%), either. And no interaction of AhR 1661G/A and ARNT 567G/C on endometriosis was found.

CONCLUSIONNo association between AhR 1661G/A and ARNT 567G/C genetic polymorphisms and endometriosis was found in the southern Han Chinese women in this study.

Alleles ; Aryl Hydrocarbon Receptor Nuclear Translocator ; genetics ; China ; Endometriosis ; genetics ; Female ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymerase Chain Reaction ; methods ; Polymorphism, Single Nucleotide ; Receptors, Aryl Hydrocarbon ; genetics

Indoxyl sulfate, a protein-bound uremic toxin, leads to CKD (chronic kidney disease) progression and its complications through the activation of AhR (aryl hydrocarbon receptor) and RAS (renin-angiotensin system). Inhibition of these pathways may slow the development of CKD and CKD-associated complications.
Indican ; Kidney ; Receptors, Aryl Hydrocarbon* ; Renal Insufficiency, Chronic ; Renin-Angiotensin System*

Aging is a significant risk factor for various diseases, including asthma, and it often leads to poorer clinical outcomes, particularly in elderly individuals. It is recognized that age-related diseases are due to a time-dependent accumulation of cellular damage, resulting in a progressive decline in cellular and physiological functions and an increased susceptibility to chronic diseases. The effects of aging affect not only the elderly but also those of younger ages, posing significant challenges to global healthcare. Thus, understanding the molecular mechanisms associated with aging in different diseases is essential. One intriguing factor is the aryl hydrocarbon receptor (AhR), which serves as a cytoplasmic receptor and ligand-activated transcription factor and has been linked to the aging process. Here, we review the literature on several major hallmarks of aging, including mitochondrial dysfunction, cellular senescence, autophagy, mitophagy, epigenetic alterations, and microbiome disturbances. Moreover, we provide an overview of the impact of AhR on these hallmarks by mediating responses to environmental exposures, particularly in relation to the immune system. Furthermore, we explore how aging hallmarks affect clinical characteristics, inflammatory features, exacerbations, and the treatment of asthma. It is suggested that AhR signaling may potentially play a role in regulating asthma phenotypes in elderly populations as part of the aging process.
Humans ; Aged ; Receptors, Aryl Hydrocarbon/metabolism* ; Asthma ; Aging ; Gene Expression Regulation ; Ligands

OBJECTIVETo study the relationship between polymorphism of aryl hydrocarbon receptor (AhR) gene in G1661A and the level of urinary 1-hydroxypyrene among coke oven workers.

METHODS295 male subjects were studied, including 214 workers working in coke oven plant and 81 controls working in raw material plant who were not generally exposed to polycyclic aromatic hydrocarbons occupationally. General in-formation of subjects were collected in a specific questionnaire including age, smoking and drinking habits, the history of occupation and so on. The AhR genotypes were detected by allele specific amplification (ASA), and the levels of urinary 1-hydroxypyrene were measured by high performance liquid chromatography with a fluorescence detector.

RESULTSThe frequencies of G/G, G/A and A/A genotype were 52.8% (113/214), 27.6% (59/214) and 19.6% (42/214) in exposed group and 67.9% (55/81), 19.8% (16/81) and 12.3% (10/81) in control group, respectively. No significant difference was found in three genotypes between the exposed and control group. Allele frequencies of G and A were 66.6% (285/428) and 33.4% (143/428) in exposed group and 77.8% (126/162) and 22.2% (36/162) in control group, and no statistical differences were found in allele frequency between exposed and control group. After the length of service and external exposure orders in general linear model were adjusted, results of covariance analysis showed that logarithmic transformed urinary 1-hydroxypyrene levels were (3.62 +/- 0.12), (3.43 +/- 0.12) and (3.44 +/- 0.08) micromol/mol Cr in individuals with A/A, G/A and G/G, respectively. The logarithmic transformed urinary 1-hydroxypyrene levels were (3.24 +/- 0.09) and (3.43 +/- 0.10) micromol/mol Cr in individuals with allele of G and A. No statistical differences were found in level of 1-hydroxypyrene among A/A, G/A and G/G genotype individuals, and between allele G and allele A after external exposure orders and length of service were adjusted.

CONCLUSIONThe polymorphism of aryl hydrocarbon receptor G1661A has no significant impact on levels of urinary 1-hydroxypyrene.

Adult ; Coke ; Genotype ; Humans ; Male ; Middle Aged ; Polymorphism, Genetic ; Pyrenes ; pharmacokinetics ; Receptors, Aryl Hydrocarbon ; genetics ; Urine ; chemistry

Particulate matter (PM), which refers to the mixture of particles present in the air, can have harmful effects. Damage to cells by PM, including disruption of organelles and proteins, can trigger autophagy, and the relationship between autophagy and PM has been well studied. However, the cellular regulators of PM-induced autophagy have not been well characterized, especially in keratinocytes. The Aryl Hydrocarbon Receptor (AhR) is expressed in the epidermis and is activated by PM. In this study, we investigated the role of the AhR in PM-induced autophagy in HaCaT cells. Our results showed that PM led to AhR activation in keratinocytes. Activation of the AhR-target gene CYP1A1 by PM was reduced by co-treatment with α-naphthoflavone (α-NF), an AhR inhibitor. We also evaluated activation of the autophagy pathway in PM-treated keratinocytes. In HaCaT cells, treatment with PM treatment led to the induction of microtubules-associated proteins light chain 3 (LC3) and p62/SQSTM1, which are essential components of the autophagy pathway. To study the role of the AhR in mediating PM-induced autophagy, we treated cells with α-NF or used an siRNA against AhR. Expression of LC3-ІІ induced by PM was decreased in a dose dependent manner by α-NF. Furthermore, knockdown of AhR with siAhR diminished PM-induced expression of LC3-ІІ and p62. Together, these results suggest that inhibition of the AhR decreases PM-induced autophagy. We confirmed these results using the autophagy-inhibitors BAF and 3-MA. Taken together, our results indicate that exposure to PM induces autophagy via the AhR in HaCaT keratinocytes.
Autophagy ; Cytochrome P-450 CYP1A1 ; Epidermis ; Keratinocytes ; Negotiating ; Organelles ; Particulate Matter ; Receptors, Aryl Hydrocarbon ; RNA, Small Interfering

aryl hydrocarbon receptor (AhR) transactivating (AHRT) activity and uremia in chronic kidney disease (CKD) may interact with each other, further complicating the disease course. In this study, we prospectively estimated serum AHRT activity using a highly sensitive cell-based AhR-dependent luciferase activity assay in CKD patients and compared differences therein according to treatment modality.MATERIALS AND METHODS: Patients undergoing peritoneal dialysis (PD) (n=22) and hemodialysis (HD) (n=38) and patients with pre-dialysis CKD stage IV or V (n=28) were included. AHRT activity and intracellular adenosine triphosphate (ATP) levels were measured. We performed a correlation analysis for AHRT activity, ATP levels, and various clinical parameters.RESULTS: AHRT activity and intracellular ATP levels were inversely correlated and differed according to treatment modalities. AHRT activity was higher in non-dialysis CKD patients than in patients undergoing dialysis and was higher in patients undergoing HD, compared to PD. AHRT activity decreased after HD treatment in HD patients. ATP levels were higher in healthy controls than in patients with pre-dialysis CKD and PD and were further decreased in patients with HD. We noted significant correlations between multiple clinical parameters associated with cardiovascular risk factors and AHRT activity.CONCLUSION: AHRT activity was elevated in CKD patients, while dialysis treatment reduced AHRT activity. Further studies are warranted to specify AHRT activity and to evaluate the precise roles thereof in patients with CKD.]]>
Adenosine Triphosphate ; Dialysis ; Humans ; Luciferases ; Peritoneal Dialysis ; Prospective Studies ; Receptors, Aryl Hydrocarbon ; Renal Dialysis ; Renal Insufficiency, Chronic ; Risk Factors ; Uremia

OBJECTIVETo establish an exonuclease protection mediated polymerase chain reaction (PCR) assay for the non-radioactive, sensitive detection of the binding of protein and DNA.

METHODSThe 1 pmol/L-10 nmol/L 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) dissolved in dimethyl sulphoxide (DMSO), was added into 100 microl SD rat hepatic cytosol in vitro, which contained different amount of aromatic hydrocarbon receptors (AhR) and relative proteins, and ligand-AhR-DRE complex were formed in addition to 1 fmol/L-100 nmol/L DNAs probes containing the sequence of DRE. With the digestion of Exonuclease III and S1 nuclease, free DNAs were digested to oligonucleotide and binding DNA remained due to protein (AhR) protection and be amplified by PCR. The results of PCRs were shown by loading on 2% agarose electrophoresis. DMSO was used as negative control and blank control was set up.

RESULTSTarget DNA (285 bp) could be observed in the ligand groups, but not in the control group. The minimal amount of receptor was 2.5 fmol/L and the minimal amount of DNA probes was 2 fmol.

CONCLUSIONSExonuclease protection mediated PCR assay should be a good non-radioactive tool to quantify the interaction of protein and DNA with high sensitivity and simplicity.

Animals ; Aryl Hydrocarbon Receptor Nuclear Translocator ; genetics ; metabolism ; Binding, Competitive ; DNA Probes ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Exonucleases ; metabolism ; Male ; Polymerase Chain Reaction ; methods ; Rats ; Rats, Sprague-Dawley ; Receptors, Aryl Hydrocarbon ; genetics ; metabolism

The intestinal immune system maintains oral tolerance to harmless antigens or nutrients. One mechanism of oral tolerance is mediated by regulatory T cell (Treg)s, of which differentiation is regulated by a subset of dendritic cell (DC)s, primarily CD103+ DCs. The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, plays an important role in regulating immunity. The intestines are exposed to various AhR ligands, including endogenous metabolites and phytochemicals. It was previously reported that AhR activation induced tolerogenic DCs in mice or in cultures of bone marrow-derived DCs. However, given the variety of tolerogenic DCs, which type of tolerogenic DCs is regulated by AhR remains unknown. In this study, we found that AhR ligand 3,3'-diindolylmethane (DIM) inhibited the development of CD103+ DCs from mouse bone marrow cells stimulated with Flt3L and GM-CSF. DIM interfered with phosphorylation of STAT3 and STAT5 inhibiting the expression of genes, including Id2, E2-2, IDO-1, and Aldh1a2, which are associated with DC differentiation and functions. Finally, DIM suppressed the ability of CD103+ DCs to induce Foxp3+ Tregs.
Animals ; Bone Marrow Cells ; Dendritic Cells* ; Granulocyte-Macrophage Colony-Stimulating Factor ; Immune System ; Intestines ; Ligands ; Mice ; Phosphorylation* ; Phytochemicals ; Receptors, Aryl Hydrocarbon ; Transcription Factors

OBJECTIVETo study the specific binding of the artificial clonal aryl hydrocarbon receptor translocator (ARNT) with the natural aryl hydrocarbon receptor (AhR) and the recolonization by polyclonal antibody. The dose-response relationship with tetrachlo-rodibenzo-dioxin (TCDD) was also studied to develop TCDD detection method and the binding degree related to dose response.

METHODS(1) The target genes including AhR-PAS, AhR-C and ARNT-PAS were amplified by RT-PCR by using the total RNA purified from the liver cells of C57BL/6J mice as templates to construct pGEX-5X1 recombinants. The recombinant plasmids were expressed in E. coli. (2) The rabbits were immuned by the clonal fusion proteins: AhR-PAS, AhR-C to prepare the polyclonal antibody. (3) The natural AhR from the hepatic cytosol of C57BL/6J mice was extracted. The artificial cloning expressed fusion protein:GST-ARNT-PAS and the natural AhR were incubated in different dose of TCDD. The quantity of the heterodimer through affinity adsorption and Western blots were measured.

RESULTS(1) The target proteins including AhR-PAS, AhR-C and ARNT-PAS were successfully cloned and expressed in E. coli. (2) The detection limit of polyclonal antibody AhR-PAS and AhR-C were 5 ng and 1 ng, respectively. (3) The total protein concentration prepared from the liver cells was 60.5 mg/ml. The artificial clonal protein ARNT-PAS could specifically bind to the natural AhR complex with the existence of TCDD. The detection limit of TCDD was 0.25 pmol which was 80 pg approximately.

CONCLUSIONA TCDD detection method based on the aryl hydrocarbon receptor system was established and the detection limit might reach pg grade.

Animals ; Cells, Cultured ; Limit of Detection ; Liver Extracts ; chemistry ; Mice ; Mice, Inbred C57BL ; Polychlorinated Dibenzodioxins ; analysis ; Rabbits ; Receptors, Aryl Hydrocarbon ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction