a-modified-quechers-hplc-method-for-detection-polycyclic-aromatic

A Modified QuEChERS-HPLC Method for Detection of Polycyclic Aromatic Hydrocarbons in Zebrafish Embryos Exposed to Fine Particulate Matter

Maternal exposure to fine particulate matter (PM2.5), with an aerodynamic diameter of 2.5 &#181;m or less, has been linked to spontaneous abortion and ...

simple-and-effective-procedure-for-hemostasis-in-mouse-arteries

Simple and Effective Procedure for Hemostasis in Mouse Arteries

During arterial puncture or cannulation in mice, permanent ligation of the artery is often required due to difficulty achieving hemostasis after needle ...

detection-of-global-dna-methylation-in-the-hearts-of-zebrafish-larvae

Detection of Global DNA Methylation in the Hearts of Zebrafish Larvae

DNA methylation is one of the most extensively studied epigenetic modifications and&#160;plays an essential role in cardiac development. The zebrafish is ...

Suzhou Medical College of Soochow University

MOE Education Key Laboratory of Geriatric Diseases and Immunology

Manzhouli International Travel Health Care Center

Accumulating body of evidence indicates that exposure to fine particulate matter (PM) is closely associated with congenital heart disease in the offspring, but the underlying molecular mechanisms remain to be elucidated. We previously reported that extractable organic matter (EOM) from PM induces reactive oxygen species (ROS) overproduction by activating aromatic hydrocarbon receptor (AHR), leading to heart defects in zebrafish embryos. We hypothesized that endoplasmic reticulum (ER) stress might be elicited by the excessive ROS production and thereby contribute to the cardiac developmental toxicity of PM. In this study, we examined the effects of EOM on endoplasmic reticulum (ER) stress, apoptosis, and Wnt signal pathway in zebrafish embryos, and explored their roles in EOM-induced heart defects. Our results showed that 4-Phenylbutyric acid (4-PBA), a pharmaceutical inhibitor of ER stress, significantly attenuated the EOM-elevated heart malformation rates. Moreover, EOM upregulated the expression levels of ER stress marker genes including CHOP and PDI in the heart of zebrafish embryos, which were counteracted by genetic or pharmaceutical inhibition of AHR activity. The ROS scavenger N-Acetyl-l-cysteine (NAC) also abolished the EOM-induced ER stress. We further demonstrated that both 4-PBA and CHOP genetic knockdown rescued the PM-induced ROS overproduction, apoptosis and suppression of Wnt signaling. In conclusion, our results indicate that PM induces AHR/ROS-mediated ER stress, which leads to apoptosis and Wnt signaling inhibition, ultimately resulting in heart defects.

Fine particulate matter induces heart defects via AHR/ROS-mediated endoplasmic reticulum stress.

Accumulating evidence suggests an association between maternal PM2.5 exposure and congenital heart diseases, but the underlying mechanisms remain unclear. We previously reported that PM2.5 induces cardiac malformations in zebrafish embryos via the aryl hydrocarbon receptor (AHR) pathway, which mediates the generation of reactive oxygen species (ROS). Since mitochondria are not only the main source of ROS but also sensitive to oxidative damage, we hypothesize that mitochondria may play an important role in the cardiac developmental toxicity of PM2.5. In this study, we demonstrated that extractable organic matter (EOM) from PM2.5 caused mitochondrial dysfunction in the heart of zebrafish embryos, including increased mitochondrial ROS (mtROS) levels, mitochondrial permeability transition pore (mPTP) opening, mitochondrial membrane potential (MMP) collapse, reduced mitochondrial ATP levels, and decreased expression levels of the mRNAs encoding mitochondrial proteins, which were attenuated by either pharmacological or genetic inhibition of AHR. We further demonstrated that improving mitochondrial function by inhibiting mPTP opening with Cyclosporin A suppressed the EOM-induced intracellular ROS and mtROS generation, MMP collapse, intrinsic apoptosis, and heart defects. Moreover, the EOM-induced mPTP opening was counteracted by inhibiting mtROS with mitoquinone mesylate (MitoQ). Supplementation with MitoQ also attenuated the EOM-induced mitochondrial dysfunction, apoptosis and heart defects. Additionally, knockdown of cyp1a1 but not cyp1b1 attenuated the EOM-induced mtROS generation and heart defects. Taken together, this study indicates that PM2.5 triggers mtROS generation via AHR-mediated cyp1a1 overexpression, which then causes mPTP opening and mitochondrial dysfunction, leading to apoptosis and heart defects.

PM2.5 induces mitochondrial dysfunction via AHR-mediated cyp1a1 overexpression during zebrafish heart development.

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPDQ) has raised significant concerns due to its widespread distribution and high toxicity to aquatic organisms. However, the cardiac developmental toxicity of 6PPDQ and the underlying mechanisms remain unclear. In this study, we observed no notable alterations in heart morphology or embryo survival in zebrafish embryos exposed to 6PPDQ (0.2-2000 μg/L) up to 3 days post-fertilization (dpf). However, concentrations at 2 μg/L or higher induced cardiac dysfunctions, leading to lethal effects at later stages (6-8 dpf). We further found that the aryl hydrocarbon receptor (AHR) inhibitor CH22351 attenuated 6PPDQ-induced cardiac dysfunctions, implicating the involvement of AHR signal pathway. Moreover, 6PPDQ exposure led to an overproduction of reactive oxygen species (ROS) and an upregulation of genes associated with oxidative stress (sod1, sod2, and nrf2a). This was accompanied by an increase in oxidative DNA damage and the induction of p53-dependent extrinsic apoptosis. Co-exposure to the ROS scavenger N-acetylcysteine effectively counteracted the DNA damage and apoptosis induced by 6PPDQ. Importantly, inhibition of AHR or its downstream target cyp1b1 attenuated 6PPDQ-induced oxidative stress, DNA damage, and apoptosis. In conclusion, our results provide evidence that 6PPDQ induces oxidative stress through the AHR/cyp1b1 signaling pathway, leading to DNA damage and extrinsic apoptosis, ultimately resulting in cardiac dysfunction.

AHR/cyp1b1 signaling-mediated extrinsic apoptosis contributes to 6PPDQ-induced cardiac dysfunction in zebrafish embryos.

The Hulunbuir region, known for its diverse terrain and rich wildlife, is a hotspot for various natural epidemic diseases. Between 2021 and 2023, we collected 885 wild rodent samples from this area, representing three families, seven genera, and eleven species. Metagenomic analysis identified three complete nucleic acid sequences from the S, M, and L segments of the  family, which were closely related to the Khabarovsk virus. The nucleotide coding sequences for S, M, and L (1392 nt, 3465 nt, and 6491 nt, respectively) exhibited similarities of 82.34%, 81.68%, and 81.94% to known sequences, respectively, while protein-level analysis indicated higher similarities of 94.92%, 94.41%, and 95.87%, respectively. Phylogenetic analysis placed these sequences within the same clade as the Khabarovsk, Puumala, Muju, Hokkaido, Topografov, and Tatenalense viruses, all of which are known to cause febrile diseases in humans. Immunofluorescence detection of nucleic acid-positive rodent kidney samples using sera from patients with hemorrhagic fever and renal syndrome confirmed the presence of viral particles. Based on these findings, we propose that this virus represents a new member of the  family, tentatively named the Amugulang virus, after its primary distribution area.

Amugulang virus, a novel hantavirus harboured by small rodents in Hulunbuir, China.

The ecological and health risks of 6PPDQ (N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone) have raised significant concerns. We recently demonstrated that the Aryl Hydrocarbon Receptor (AhR) mediates 6PPDQ-caused extrinsic apoptosis and heart defects; however, the underlying molecular pathways remain elucidated. In this study, we observed that inhibition of Protein Kinase A (PKA) effectively mitigated 6PPDQ-caused apoptosis and cardiac dysfunction in zebrafish larvae. Subsequent experiments revealed significant increases in both PKA levels and cyclic adenosine monophosphate (cAMP) concentrations within the hearts of zebrafish embryos exposed to 6PPDQ. Notably, pharmacological inhibition or genetic knockdown of AhR abolished 6PPDQ-induced PKA overexpression. Dual-luciferase reporter assays indicated that AhR activation by 6PPDQ directly enhance the transcription of adcy6a, which encodes an adenylate cyclase (AC) isoform predominately expressed in the heart of zebrafish. Inhibition of β-adrenergic receptors did not significantly influence the AC/cAMP/PKA cascade. Furthermore, exposure to 6PPDQ induced phosphorylation of cAMP response element-binding protein (CREB), an effect that was mitigated by PKA inhibition. Activated CREB subsequently promoted the expression of Fos, a component of the activator protein-1 (AP-1) transcription factor family. Inhibition of Fos (AP-1) counteracted the 6PPDQ-induced overexpression of fas and faslg, as well as the subsequent extrinsic apoptosis. In conclusion, our findings indicate that AhR activation by 6PPDQ triggers AC/cAMP/PKA cascade through direct transcriptional upregulation of adcy6a. PKA-mediated phosphorylation of CREB then facilitates the overexpression of fas and faslg via AP-1, resulting in extrinsic apoptosis and cardiac defects.

ArticleTotal : 3	Year
Publication title Cited by 1	2025
Publication title	2025
Publication title	2026

Article	Year
Fine particulate matter induces heart defects via AHR/ROS-mediated endoplasmic reticulum stress. Chemosphere\| PubMed ID: 35948106	2022
PM2.5 induces mitochondrial dysfunction via AHR-mediated cyp1a1 overexpression during zebrafish heart development. Toxicology\| PubMed ID: 36841371	2023
AHR/cyp1b1 signaling-mediated extrinsic apoptosis contributes to 6PPDQ-induced cardiac dysfunction in zebrafish embryos. Environmental pollution (Barking, Essex : 1987)\| PubMed ID: 38311157	2024
Amugulang virus, a novel hantavirus harboured by small rodents in Hulunbuir, China. Emerging microbes & infections\| PubMed ID: 39178299	2024
Contribution of AhR-mediated activation of the AC/cAMP/PKA cascade to 6PPDQ-induced cardiac defects in zebrafish. Environmental research\| PubMed ID: 41651144	2026

Mingxuan Zhang

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