Flubendazole exposure disrupts neural development and function of zebrafish embryos (Danio rerio).

Flubendazole (FBZ) is a benzimidazole anthelmintic drug widely used for treating parasitic infections by disrupting microtubule formation and function through tubulin binding. Recently, its use has extended to include anticancer applications, leading to increased environmental exposure to benzimidazole drugs. However, the impact of FBZ on neural development in aquatic organisms, particularly in aquatic vertebrates, remains poorly understood. This study aimed to investigate the potential developmental toxicity of FBZ during neural development using zebrafish model. Various assessments, including analysis of overall developmental changes, morphological abnormalities, apoptosis, gene expression alterations, axon length measurements, and electrophysiological neural function, were performed. FBZ exposure resulted in concentration-dependent effects on survival rate, hatching rate, heartbeat, and the occurrence of developmental abnormalities. Notably, FBZ-induced changes included reductions in body length, head size, and eye size, as well as the detection of apoptotic cells in the central nervous system. Gene expression analysis revealed upregulation of apoptosis-related genes (p53, casp3, and casp8), downregulation of neural differentiation-related genes (shha, nrd, ngn1, and elavl3), and alterations in neural maturation and axon growth-related genes (gap43, mbp, and syn2a). Additionally, shortened motor neuron axon length and impaired electrophysiological neural function were observed. These findings provide novel insights into the potential risks of FBZ on the neural development of zebrafish embryos, emphasizing the need for risk prevention strategies and therapeutic approaches to address the environmental toxicity of benzimidazole anthelmintics.

Postnatal exposure to trimethyltin chloride induces retinal developmental neurotoxicity in mice via glutamate and its transporter related changes.

Exposure to toxic substances during postnatal period is one of the major factors causing retinal developmental defects. The developmental toxicity of trimethyltin chloride (TMT), a byproduct of an organotin compound widely used in agriculture and industrial fields, has been reported; however, the effect on the mammalian retina during postnatal development and the mechanism have not been elucidated to date. We exposed 0.75 and 1.5 mg/kg of TMT to neonatal ICR mice (1:1 ratio of male and female) up to postnatal day 14 and performed analysis of the retina: histopathology, apoptosis, electrophysiological function, glutamate concentration, gene expression, and fluorescence immunostaining. Exposure to TMT caused delayed eye opening, eye growth defect and thinning of retinal layer. In addition, apoptosis occurred in the retina along with b-wave and spiking activity changes in the micro-electroretinogram. These changes were accompanied by an increase in the concentration of glutamate, upregulation of astrocyte-related genes, and increased expression of glial excitatory amino acid transporter (EAAT) 1 and 2. Conversely, EAAT 3, 4, and 5, mainly located in the neurons, were decreased. Our results are the first to prove postnatal retinal developmental neurotoxicity of TMT at the mammalian model and analyze the molecular, functional as well as morphological aspects to elucidate possible mechanisms: glutamate toxicity with EAAT expression changes. These mechanisms may suggest not only a strategy to treat but also a clue to prevent postnatal retina developmental toxicity of toxic substances.

Eliminating murine norovirus, Helicobacter hepaticus, and intestinal protozoa by embryo transfer for an entire mouse barrier facility.

Pathogens can affect physiological and immunological reactions in immunocompromised animals and genetically engineered mice. Specifically, murine norovirus (MNV), Helicobacter, and intestinal protozoa are prevalent in rodent laboratory facilities worldwide. In this study, microbiological test results of the soiled bedding of sentinel mice showed the prevalence of MNV (50.9%, 28/55), Helicobacter hepaticus (29.1%, 16/55), Trichomonas spp. (14.5%, 8/55), and Entamoeba spp. (32.7%, 18/55). No single infections were detected as all cases were confirmed to have complex infections with two or four pathogens. In previous studies, the success rate of the cross-fostering method was not perfect; therefore, in this study, the entire mouse strain of the SPF rodent facility was rederived using embryo transfer. For up to three years, we confirmed that the results were negative with regular health surveillance tests. Embryo transfer was, thus, determined to be an effective method for the rederivation of specific pathogen free (SPF) barrier mouse facilities. This is the report for the effectiveness of embryo transfer as an example of successful microbiological clean-up of a mouse colony with multiple infections in an entire SPF mouse facility and embryo transfer may be useful for rederiving.

Albendazole exerts antiproliferative effects on prostate cancer cells by inducing reactive oxygen species generation.

Benzimidazole derivatives are used for their antihelmintic properties, but have also been reported to exert anticancer effects. In the present study, the anticancer effects of albendazole on prostate cancer cells were assessed using proliferation, clonogenic and migration assays. To investigate the anticancer mechanisms of albendazole, reactive oxygen species (ROS) levels were measured, and the expression of genes associated with oxidative stress and Wnt/ß-catenin signaling was confirmed by reverse transcription-quantitative PCR and western blotting. Albendazole selectively inhibited the proliferation of the PC3, DU145, LNCaP and AT2 prostate cancer cell lines at concentrations that did not affect the proliferation of a normal prostate cell line (RWPE-1). Albendazole also inhibited the colony formation and migration of PC3 and DU145 cells, as well as inducing ROS production. Diphenyleneiodonium chloride, an inhibitor of NADPH oxidase (NOX), one of the sources of ROS, decreased basal ROS levels in the PC3 and DU145 cells, but did not reduce albendazole-associated ROS production, suggesting that ROS production following albendazole treatment was NOX-independent. The anticancer effect was decreased when albendazole-induced ROS was reduced by treatment with antioxidants (glutathione and N-acetylcysteine). Furthermore, albendazole decreased the mRNA expression of CDGSH iron sulfur domain 2, which regulates antioxidant activity against ROS, as well as the antioxidant enzymes catalase, and glutathione peroxidase 1 and 3. Albendazole also decreased the mRNA expression of catenin ß1 and transcription factor 4, which regulate Wnt/ß-catenin signaling and its associated targets, Twist family BHLH transcription factor 1 and BCL2. The albendazole-related decrease in the expression levels of oxidative stress-related genes and Wnt/ß-catenin signaling proteins was thought to be associated with ROS production. These results suggest that the antihelmintic drug, albendazole, has inhibitory effects against prostate cancer cells in vitro. Therefore, albendazole may potentially be used as a novel anticancer agent for prostate cancer.

Loss of glutathione peroxidase 3 induces ROS and contributes to prostatic hyperplasia in Nkx3.1 knockout mice.

BACKGROUND: Glutathione peroxidase 3 (Gpx3) protects cells from oxidative stress, and its reduced expression in human prostate cancer has been reported. OBJECTIVES: We hypothesized that Gpx3 might play an important role in the development of prostatic intraepithelial neoplasia (PIN), a pre-cancerous state of the prostate, and aimed to highlight the underlying molecular mechanism. MATERIALS AND METHODS: The following double-knockout mice Nkx3.1-/-; Gpx3+/+, Nkx3.1-/-; Gpx3+/-, Nkx3.1-/-; Gpx3-/- were produced. Randomly divided animals were weighed, and their genitourinary tract (GUT) weights were determined after euthanasia at 4, 8, and 12 months. The mRNA expression of the genes involved in oxidative stress and Wnt signaling was analyzed in the prostate. Histopathology, ROS, and superoxide dismutase (SOD) activities were also measured. RESULTS: Loss of Gpx3 did not affect body weight and GUT weight in Nkx3.1 knockout mice. The mRNA expression of SOD3, iNOS, Hmox, and CISD2, which are associated with oxidative stress, was increased in Nkx3.1-/-; Gpx3-/- mice at 4 months but decreased at 8 and 12 months. There was no change in ß-catenin and its targets associated with Wnt signaling. Increased ROS and decreased SOD activity were observed in Nkx3.1-/-; Gpx3-/- mice at 12 months of age. The histopathologic score and epithelium thickness were increased, and lumen area was decreased in Gpx3 knockout mice. DISCUSSION AND CONCLUSIONS: Gpx3 loss increased the hyperplasia of PIN in the pre-cancerous stage of the prostate. Loss of Gpx3 induced oxidative stress. Histopathologically, no invasive carcinoma was identified, and Gpx3 loss did not increase Wnt/ß-catenin signaling. Further research on the role of GPX3 in the transition of PIN to invasive carcinoma is needed. We show, for the first time, that the antioxidant enzyme GPX3 plays a vital role in inhibiting hyperplasia in the PIN stage of the prostate gland in vivo.