GEO DataSets

(Submitter supplied) Dioxin-like chemicals are well-known for their ability to upregulate expression of numerous genes via the AH receptor (AHR). However, recent transcriptomic analyses in several laboratories indicate that dioxin-like chemicals or AHR genotype itself also can downregulate levels of mRNAs encoded by numerous genes. The mechanism responsible for such downregulation is unknown. We hypothesized that microRNAs (miRNAs), which have emerged as powerful negative regulators of mRNA levels in several systems, might be responsible for mRNA downregulation in dioxin/AHR pathways. more...

Organism:

Homo sapiens; Mus musculus; Rattus norvegicus

Type:

Non-coding RNA profiling by array

Platform:

GPL5531

8 Samples

Download data: GPR

(Submitter supplied) This SuperSeries is composed of the SubSeries listed below.

Organism:

Rattus norvegicus; Homo sapiens; Mus musculus

Type:

Non-coding RNA profiling by array

Platforms:

GPL3444 GPL5531

50 Samples

Download data: GPR

(Submitter supplied) Dioxin-like chemicals are well-known for their ability to upregulate expression of numerous genes via the AH receptor (AHR). However, recent transcriptomic analyses in several laboratories indicate that dioxin-like chemicals or AHR genotype itself also can downregulate levels of mRNAs encoded by numerous genes. The mechanism responsible for such downregulation is unknown. We hypothesized that microRNAs (miRNAs), which have emerged as powerful negative regulators of mRNA levels in several systems, might be responsible for mRNA downregulation in dioxin/AHR pathways. more...

Organism:

Homo sapiens; Mus musculus; Rattus norvegicus

Type:

Non-coding RNA profiling by array

Platform:

GPL5531

20 Samples

Download data: GPR

(Submitter supplied) Dioxin-like chemicals are well-known for their ability to upregulate expression of numerous genes via the AH receptor (AHR). However, recent transcriptomic analyses in several laboratories indicate that dioxin-like chemicals or AHR genotype itself also can downregulate levels of mRNAs encoded by numerous genes. The mechanism responsible for such downregulation is unknown. We hypothesized that microRNAs (miRNAs), which have emerged as powerful negative regulators of mRNA levels in several systems, might be responsible for mRNA downregulation in dioxin/AHR pathways. more...

Organism:

Rattus norvegicus; Mus musculus; Homo sapiens

Type:

Non-coding RNA profiling by array

Platform:

GPL5531

6 Samples

Download data: GPR

(Submitter supplied) Dioxin-like chemicals are well-known for their ability to upregulate expression of numerous genes via the AH receptor (AHR). However, recent transcriptomic analyses in several laboratories indicate that dioxin-like chemicals or AHR genotype itself also can downregulate levels of mRNAs encoded by numerous genes. The mechanism responsible for such downregulation is unknown. We hypothesized that microRNAs (miRNAs), which have emerged as powerful negative regulators of mRNA levels in several systems, might be responsible for mRNA downregulation in dioxin/AHR pathways. more...

Organism:

Homo sapiens; Mus musculus; Rattus norvegicus

Type:

Non-coding RNA profiling by array

Platform:

GPL3444

16 Samples

Download data: GPR

(Submitter supplied) The dioxin congener 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a wide range of toxic effects in rodent species, all of which are mediated by a ligand-dependent transcription-factor, the aryl hydrocarbon receptor (AHR). The Han/Wistar (Kuopio) (H/W) strain shows exceptional resistance to many TCDD-induced toxicities; the LD50 of >9600 µg/kg for H/W rats is higher than for any other wild-type mammal known. more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL9199

45 Samples

Download data: CEL, DAT

(Submitter supplied) Profiling of mRNA abundances with high-throughput platforms such as microarrays and RNA-Seq has become an important tool in both basic and biomedical research. However these platforms remain prone to systematic errors, and have challenges in clinical and industrial application. As a result it is standard practice to validate a subset of key results using alternate technologies. Similarly, clinical and industrial applications typically involve transitions from high-throughput discovery platform to medium-throughput validation ones. more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array; Expression profiling by RT-PCR

Platforms:

GPL16146 GPL16444 GPL16145

458 Samples

Download data: TXT

(Submitter supplied) We profiled hepatic transcriptional responses of 6 strains of rats with varying sensitivity to a dioxin, TCDD, at 19 hours following exposure. The resistant rats exhibited significantly reduced transcriptional responses in comparison to the sensitive strains. We hypothesize that genes which show differential changes between the resistant and sensitive rats may potentially explain sensitivity.

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platforms:

GPL14123 GPL14122

56 Samples

Download data: CEL

(Submitter supplied) Conventional biochemical and molecular techniques identified previously several genes whose expression is regulated by the aryl hydrocarbon receptor (AHR). We sought to map the complete spectrum of AHR-dependent genes in male adult liver using expression arrays to contrast mRNA profiles in Ahr-null mice (Ahr–/–) with those in mice with wild-type AHR (Ahr+/+). Transcript profiles were determined both in untreated mice and in mice treated 19 h earlier with 1000 µg/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL1261

17 Samples

Download data: CEL, DAT, EXP

(Submitter supplied) Environmental contaminants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), are known to cause a wide range of toxicities. The consequences of acute exposure to TCDD in rodents, and to a lesser degree in humans, can range from mild chloracne to terminal illness, such as cancer. The aryl hydrocarbon receptor (AHR) plays a critical role in mediating the toxic effects of TCDD. However, the underlying mechanism of differential sensitivities to TCDD across organisms remain poorly understood, however differences in the AHR are known to play a role. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platforms:

GPL26227 GPL24557

34 Samples

Download data: CEL

(Submitter supplied) The aryl hydrocarbon receptor (AHR) mediates most of the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, TCDD toxicity phenotypes vary widely between species, strains and even between sexes within a strain. While the exact reasons for this variation remain unclear, it is thought to be related to differences in the structure of the AHR. Previous studies comparing the downstream effects of TCDD exposure between animals with different AHR isoforms have been confounded by the genetic differences between these model systems. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL20837

60 Samples

Download data: CEL

(Submitter supplied) Rodents exposed to the environmental contaminant, TCDD, suffer from a number of acute and chronic toxicities, including lethality and a wasting syndrome. Hypothesizing that the wasting syndrome may be caused by changes in adipose tissue -- either in its hormonal regulation or in homeostatic effects -- we profiled the transcriptional response of rat white adipose to TCDD. We employed two separate rat strains: the Long-Evans strain is sensitive to TCDD toxicities while the Han/Wistar strain is over four orders of magnitude more resistant. more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL9199

28 Samples

Download data: CEL, DAT

(Submitter supplied) Major toxicities of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) result from dysregulation of gene expression mediated by the aryl hydrocarbon receptor (AHR). Dioxin-like chemicals alter expression of numerous genes in liver but the specific genes whose dysregulation leads to toxicities such as wasting, hepatotoxicity and lethality have not been identified. We searched for genes that are most likely to be key to dioxin toxicity by using gene expression arrays to contrast hepatic gene expression after TCDD treatment in dioxin-sensitive rats (that carry wildtype AHR) with gene expression in H/W(Kuopio) rats which are highly resistant to dioxin toxicity due to a major deletion in the AHR's transactivation domain (TAD). more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL341

40 Samples

Download data: CEL, DAT, EXP

(Submitter supplied) This study investigates the effects of the aryl hydrocarbon receptor (AhR) ligands TCDD, PCB126 and PeCDF; the non-AhR ligand PCB153 and the binary mixture PCB126/PCB153 on hepatic gene expression in female sprague dawley rats. Rats were treated with toxicological equivalent doses of TCDD (100ng/kg), PeCDF (200ng/kg), PCB126 (1000ng/kg) and PCB153 (1000ug/kg) 5 days a week for 13 weeks. Keywords: Environmental pollutant toxicity comparison

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL85

21 Samples

Download data: CEL

(Submitter supplied) 2,3,7,8–tetrachlorodibenzo-p-dixion (TCDD) is the most potent of the dioxin congeners, capable of causing a wide range of toxic effects across numerous animal models. Previous studies have demonstrated that males and females of the same species can display divergent sensitivity phenotypes to TCDD toxicities. Although it is now clear that most TCDD-induced toxic outcomes are mediated by the aryl hydrocarbon receptor (AHR), the mechanism of differential responses to TCDD exposure between sexes remains largely unknown. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL17153

40 Samples

Download data: CEL

(Submitter supplied) This SuperSeries is composed of the SubSeries listed below.

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL8492

35 Samples

Download data: CEL

(Submitter supplied) The aryl hydrocarbon receptor (AHR) is a widely-expressed ligand-dependent transcription-factor that mediates cellular responses to dioxins and other planar aromatic hydrocarbons. Indeed, AHR-null mice are refractory to the physiological effects of dioxin-exposure. Although some mechanistic aspects of AHR activity are well understood, the tissue-specificity of AHR effects remains unclear, both during development and following administration of exogenous ligands. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL8492

17 Samples

Download data: CEL

(Submitter supplied) The aryl hydrocarbon receptor (AHR) is a widely-expressed ligand-dependent transcription-factor that mediates cellular responses to dioxins and other planar aromatic hydrocarbons. Indeed, AHR-null mice are refractory to the physiological effects of dioxin-exposure. Although some mechanistic aspects of AHR activity are well understood, the tissue-specificity of AHR effects remains unclear, both during development and following administration of exogenous ligands. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL8492

18 Samples

Download data: CEL

(Submitter supplied) IMA-08401 (C2) represents a novel AHR agonist and selective AHR modulator (SAHRM) that is structurally similar to laquinimod (LAQ). Although both compounds produce an identical AHR-active metabolite, IMA-06201 (DELAQ) in vivo, C2 generates it to a far greater degree. SAHRMs have been proposed as therapeutic options for autoimmune disorders, including multiple sclerosis. So far, clinical trials on LAQ have not reported any significant toxic outcomes and C2 has shown low toxicity in rats; however, more research is required due to the functional resemblance of these compounds to the highly toxic AHR agonist, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL26164

23 Samples

Download data: CEL

(Submitter supplied) Background Mouse and rat models are mainstays in pharmacology, toxicology and drug development – but differences between strains and between species complicate data interpretation and application to human health. Dioxin-like polyhalogenated aromatic hydrocarbons represent a major class of environmentally and economically relevant toxicants. In mammals dioxin exposure leads to a broad spectrum of adverse affects, including hepatotoxicity of varying severity. more...

Organism:

Rattus norvegicus

Type:

Expression profiling by array

Platform:

GPL341

8 Samples

Download data: CEL, DAT