Borrelia burgdorferi sensu lato (Bbsl) is spirochetes transmitted by ticks and known to cause Lyme disease. Chlamydia-like organisms (CLOs) comprise a large group of bacteria that can lead to serious health disorders, including miscarriage. Recently, CLOs have been found in ticks and patient skin biopsies. Due to the involvement of multiple potential vectors in the spread of these pathogens, the objective of this study was to confirm the presence of both organisms in the early developmental stages of selected vectors. Three potential vectors, Ixodes ricinus larvae, Culex pipiens larvae, and winged (unfed) adults of Lipoptena cervi, were collected in the Czech Republic in years 2019-2020. The presence of Bbsl and panchlamydial DNA was detected by PCR and positive samples were further analyzed by Sanger sequencing and phylogenetic tree construction. Bbsl DNA was proved in 1.5% (2/137) of I. ricinus larvae (identified as Borrelia afzelii and Borrelia garinii), in 1.7% (2/119) of C. pipiens larvae (both identified as B. garinii), and in 11% (3/27) of L. cervi (all identified as B. garinii). CLOs were identified in 0.7% (1/137) of I. ricinus larvae (Candidatus Protochlamydia) and in 7.4% (2/27) of L. cervi (unspecified genus), while C. pipiens larvae could not be evaluated (0%). This research represents the first investigation of the presence of CLOs in L. cervi. The detection of pathogen DNA in the early developmental stages of vectors suggests the potential for transgenerational transmission of Bbsl and CLOs in the selected vectors, although at a low rate.

• MeSH
• Borrelia burgdorferi komplex * izolace a purifikace   MeSH
• Chlamydia * izolace a purifikace   genetika   MeSH
• členovci - vektory * mikrobiologie   MeSH
• DNA bakterií izolace a purifikace   MeSH
• fylogeneze MeSH
• klíště * mikrobiologie   růst a vývoj   MeSH
• larva mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• DNA bakterií MeSH

Both aryl hydrocarbon receptor (AhR) and pregnane X receptor (PXR) belong among key regulators of xenobiotic metabolism in the intestinal tissue. AhR in particular is activated by a wide range of environmental and dietary carcinogens. The data accumulated over the last two decades suggest that both of these transcriptional regulators play a much wider role in the maintenance of gut homeostasis, and that both transcription factors may affect processes linked with intestinal tumorigenesis. Intestinal epithelium is continuously exposed to a wide range of AhR, PXR and dual AhR/PXR ligands formed by intestinal microbiota or originating from diet. Current evidence suggests that specific ligands of both AhR and PXR can protect intestinal epithelium against inflammation and assist in the maintenance of epithelial barrier integrity. AhR, and to a lesser extent also PXR, have been shown to play a protective role against inflammation-induced colon cancer, or, in mouse models employing overactivation of Wnt/β-catenin signaling. In contrast, other evidence suggests that both receptors may contribute to modulation of transformed colon cell behavior, with a potential to promote cancer progression and/or chemoresistance. The review focuses on both overlapping and separate roles of the two receptors in these processes, and on possible implications of their activity within the context of intestinal tissue.

• Klíčová slova
• Aryl hydrocarbon receptor, Colon cancer, Dietary contaminants, Epithelial barrier, Inflammation, Intestine, Microbial agonists, Pregnane X receptor,
• MeSH
• karcinogeneze genetika   metabolismus   MeSH
• kolon metabolismus   MeSH
• myši MeSH
• pregnanový X receptor metabolismus   MeSH
• receptory aromatických uhlovodíků * genetika   metabolismus   MeSH
• steroidní receptory * metabolismus   MeSH
• zánět metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• pregnanový X receptor MeSH
• receptory aromatických uhlovodíků * MeSH
• steroidní receptory * MeSH

Polycyclic aromatic sulfur heterocyclic compounds (PASHs) belong among ubiquitous environmental pollutants; however, their toxic effects remain poorly understood. Here, we studied the aryl hydrocarbon receptor (AhR)-mediated activity of dibenzothiophene, benzo[b]naphtho[d]thiophenes, and naphthylbenzo[b]thiophenes, as well as their presence in two types of environmental matrices: river sediments collected from both rural and urban areas, and in airborne particulate matter (PM2.5) sampled in cities with different levels and sources of pollution. Benzo[b]naphtho[2,1-d]thiophene, benzo[b]naphtho[2,3-d]thiophene, 2,2-naphthylbenzo[b]thiophene, and 2,1-naphthylbenzo[b]thiophene were newly identified as efficient AhR agonists in both rat and human AhR-based reporter gene assays, with 2,2-naphthylbenzo[b]thiophene being the most potent compound identified in both species. Benzo[b]naphtho[1,2-d]thiophene and 3,2-naphthylbenzo[b]thiophene elicited AhR-mediated activity only in the rat liver cell model, while dibenzothiophene and 3,1-naphthylbenzo[b]thiophene were inactive in either cell type. Independently of their ability to activate the AhR, benzo[b]naphtho[1,2-d]thiophene, 2,1-naphthylbenzo[b]thiophene, 3,1-naphthylbenzo[b]thiophene, and 3,2-naphthylbenzo[b]thiophene inhibited gap junctional intercellular communication in a model of rat liver epithelial cells. Benzo[b]naphtho[d]thiophenes were dominant PASHs present in both PM2.5 and sediment samples, with benzo[b]naphtho[2,1-d]thiophene being the most abundant one, followed by benzo[b]naphtho[2,3-d]thiophene. The levels of naphthylbenzo[b]thiophenes were mostly low or below detection limit. Benzo[b]naphtho[2,1-d]thiophene and benzo[b]naphtho[2,3-d]thiophene were identified as the most significant contributors to the AhR-mediated activity in the environmental samples evaluated in this study. Both induced nuclear translocation of the AhR, and they induced CYP1A1 expression in a time-dependent manner, suggesting that their AhR-mediated activity may depend on the rate of their intracellular metabolism. In conclusion, some PASHs could be significant contributors to the overall AhR-mediated toxicity of complex environmental samples suggesting that more attention should be paid to the potential health impacts of this group of environmental pollutants.

• Klíčová slova
• AhR activity, Airborne particulate matter, Freshwater sediments, Gap junctional intercellular communication, Polycyclic aromatic sulfur heterocyclic compounds,
• MeSH
• heterocyklické sloučeniny * MeSH
• krysa rodu Rattus MeSH
• látky znečišťující životní prostředí * MeSH
• lidé MeSH
• pevné částice MeSH
• receptory aromatických uhlovodíků MeSH
• thiofeny toxicita   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dibenzothiophene MeSH Prohlížeč
• heterocyklické sloučeniny * MeSH
• látky znečišťující životní prostředí * MeSH
• pevné částice MeSH
• receptory aromatických uhlovodíků MeSH
• thiofeny MeSH

BACKGROUND: Inhalation of lead oxide nanoparticles (PbO NPs), which are emitted to the environment by high-temperature technological processes, heavily impairs target organs. These nanoparticles pass through the lung barrier and are distributed via the blood into secondary target organs, where they cause numerous pathological alterations. Here, we studied in detail, macrophages as specialized cells involved in the innate and adaptive immune response in selected target organs to unravel their potential involvement in reaction to subchronic PbO NP inhalation. In this context, we also tackled possible alterations in lipid uptake in the lungs and liver, which is usually associated with foam macrophage formation. RESULTS: The histopathological analysis of PbO NP exposed lung revealed serious chronic inflammation of lung tissues. The number of total and foam macrophages was significantly increased in lung, and they contained numerous cholesterol crystals. PbO NP inhalation induced changes in expression of phospholipases C (PLC) as enzymes linked to macrophage-mediated inflammation in lungs. In the liver, the subchronic inhalation of PbO NPs caused predominantly hyperemia, microsteatosis or remodeling of the liver parenchyma, and the number of liver macrophages also significantly was increased. The gene and protein expression of a cholesterol transporter CD36, which is associated with lipid metabolism, was altered in the liver. The amount of selected cholesteryl esters (CE 16:0, CE 18:1, CE 20:4, CE 22:6) in liver tissue was decreased after subchronic PbO NP inhalation, while total and free cholesterol in liver tissue was slightly increased. Gene and protein expression of phospholipase PLCβ1 and receptor CD36 in human hepatocytes were affected also in in vitro experiments after acute PbO NP exposure. No microscopic or serious functional kidney alterations were detected after subchronic PbO NP exposure and CD68 positive cells were present in the physiological mode in its interstitial tissues. CONCLUSION: Our study revealed the association of increased cholesterol and lipid storage in targeted tissues with the alteration of scavenger receptors and phospholipases C after subchronic inhalation of PbO NPs and yet uncovered processes, which can contribute to steatosis in liver after metal nanoparticles exposure.

• Klíčová slova
• Cholesterol metabolism, Inhalation, Lead oxide nanoparticles, Liver macrophages, Lung macrophages,
• MeSH
• cholesterol MeSH
• fosfolipasy typu C * MeSH
• kovové nanočástice * chemie   MeSH
• lidé MeSH
• makrofágy MeSH
• olovo MeSH
• oxidy MeSH
• zánět MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cholesterol MeSH
• fosfolipasy typu C * MeSH
• lead oxide MeSH Prohlížeč
• olovo MeSH
• oxidy MeSH