Toxicological Research最新文献

Glioblastoma (GBM) is the most aggressive type of central nervous system tumor. Molecular targeting may be important when developing efficient GBM treatment strategies. Sequencing of GBMs revealed that the receptor tyrosine kinase (RTK)/RAS/phosphatidylinositol-3-kinase pathway was altered in 88% of samples. Interestingly, AXL, a member of RTK, was proposed as a promising target in glioma therapy. However, the molecular mechanism of AXL modulation of GBM genesis and proliferation is still unclear. In this study, we investigated the expression and localization of hypoxia-inducible factor-1 alpha (HIF-1α) by AXL in GBM. Both AXL mRNA and protein are overexpressed in GBM. Short-interfering RNA knockdown of AXL in U251-MG cells reduced viability and migration. However, serum withdrawal reduced AXL expression, abolishing the effect on viability. AXL is also involved in hypoxia regulation. In hypoxic conditions, the reduction of AXL decreased the level and nuclear localization of HIF-1α. The co-expression of HIF-1α and AXL was found in human GBM samples but not normal tissue. This finding suggests a mechanism for GBM proliferation and indicates that targeting AXL may be a potential GBM therapeutic.

Supplementary information: The online version contains supplementary material available at 10.1007/s43188-023-00195-z.

The increase in the types and complexity of diseases has led to significant advances in diagnostic techniques and the availability of effective therapies. Recent studies have focused on the role of mitochondrial dysfunction in the pathogenesis of cardiovascular diseases (CVDs). Mitochondria are important organelles in cells that generate energy. Besides the production of adenosine triphosphate (ATP), the energy currency of cells, mitochondria are also involved in thermogenesis, control of intracellular calcium ions (Ca²⁺), apoptosis, regulation of reactive oxygen species (ROS), and inflammation. Mitochondrial dysfunction has been implicated in several diseases including cancer, diabetes, some genetic diseases, and neurogenerative and metabolic diseases. Furthermore, the cardiomyocytes of the heart are rich in mitochondria due to the large energy requirement for optimal cardiac function. One of the main causes of cardiac tissue injuries is believed to be mitochondrial dysfunction, which occurs via complicated pathways which have not yet been completely elucidated. There are various types of mitochondrial dysfunction including mitochondrial morphological change, unbalanced levels of substances to maintain mitochondria, mitochondrial damage by drugs, and mitochondrial deletion and synthesis errors. Most of mitochondrial dysfunctions are linked with symptoms and diseases, thus we focus on parts of mitochondrial dysfunction about fission and fusion in cardiomyocytes, and ways to understand the mechanism of cardiomyocyte damage by detecting oxygen consumption levels in the mitochondria.

UV filters in environmental compartments are a source of concern related to their ecotoxicological effects. However, little is known about UV filters' toxicity, particularly those released into the environment as mixtures. Acute toxicity of nine organic UV filters benzophenone-1, benzophenone-2, benzophenone-3, 4-methoxy benzylidene camphor, octocrylene, ethylhexyl methoxycinnamate, 2-ethylhexyl salicylate, homosalate, and butyl methoxydibenzoylmethane was determined. UV filter solutions were tested as single, binary, and ternary mixtures of various compositions. Single solutions were tested using a set of bio tests, including tests on saline crustaceans (Artemia franciscana), freshwater crustaceans (Daphnia magna), marine bacteria (Aliivibrio fischeri), and freshwater plants (Lemna minor). The tests represent different stages of the trophic chain, and hence their overall results could be used to risk assessment concerning various water reservoirs. The toxicity of binary and ternary mixtures was analyzed using the standardized Microtox^® method. Generally, organic UV filters were classified as acutely toxic. Octocrylene was the most toxic for Arthemia franciscana (LC₅₀ = 0.55 mg L^-1) and Daphnia magna (EC₅₀ = 2.66-3.67 mg L^-1). The most toxic against freshwater plants were homosalate (IC₅₀ = 1.46 mg L^-1) and octocrylene (IC₅₀ = 1.95 mg L^-1). Ethylhexyl methoxycinnamate (EC₅₀ = 1.38-2.16 mg L^-1) was the most toxic for marine bacteria. The least toxic for crustaceans and plants were benzophenone-1 (EC₅₀ = 6.15-46.78 mg L^-1) and benzophenone-2 (EC₅₀ = 14.15-54.30 mg L^-1), while 4-methoxy benzylidene camphor was the least toxic for marine bacteria (EC₅₀ = 12.97-15.44 mg L^-1). Individual species differ in their sensitivity to the tested organic UV filters. An assessment of the toxicity of mixtures indicates high and acute toxicity to marine bacteria after exposition to a binary mixture of benzophenone-2 with octocrylene, 2-ethylhexyl salicylate, or homosalate. The toxicity of mixtures was lower than single solutions predicting antagonistic interaction between chemicals.

Graphical abstract:

Autophagy play contradictory roles in cellular transformation. We previously found that the knockout (KO) of autophagy-related 5 (Atg5), which is essential for autophagy, leads to the malignant transformation of NIH 3T3 cells. In this study, we explored the mechanism by which autophagy contributes to this malignant transformation using two transformed cell lines, Atg5 KO and Ras-NIH 3T3. Monomeric red fluorescent protein-green fluorescent protein-light chain 3 reporter and Cyto-ID staining revealed that Ras-NIH 3T3 cells exhibited higher basal autophagy activity than NIH 3T3 cells. Additionally, transformed cells, regardless of their Atg5 KO status, were more sensitive to autophagy inhibitors (SBI-0206965, chloroquine, and obatoclax) than the untransformed NIH 3T3 cells, suggesting that the transformed cells are more autophagy-dependent than the normal cells. Loss of Atg5 improved the cell viability and mobility, especially in Ras-NIH 3T3 cells. Furthermore, we discovered that autophagy was alternatively induced in a Rab9-dependent manner in Ras-NIH 3T3 and NIH 3T3/Atg5 KO cells. In particular, Atg5 KO cells showed reduced mTOR-mediated phosphorylation of Akt (pAkt S473), indicating the mTOR-independent occurrence of alternative autophagy in Atg5 KO cells. Therefore, our study provides evidence that alternative autophagy may contribute to tumorigenesis in cells with an impaired Atg5-dependent autophagy pathway.

Supplementary information: The online version contains supplementary material available at 10.1007/s43188-023-00191-3.

Porphyromonas gingivalis (P. gingivalis), a key pathogen in periodontal diseases, is also associated with hyperglycemia-associated systemic diseases, including diabetes mellitus (DM). Gingipains are the most important endotoxins of P. gingivalis, and in vivo studies using gingipains are scarce. Zebrafish (Danio rerio) is a vertebrate with high physiological and genetic homology with humans that has multiple co-orthologs for human genes, including inflammation-related proteins. The aim of our study was to determine the effects of gingipain in a hyperglycemia-induced zebrafish model by evaluating inflammation, oxidant-antioxidant status, and the cholinergic system. Adult zebrafish were grouped into the control group (C), hyperglycemia-induced group subjected to 15 days of overfeeding (OF), gingipain-injected group (GP), and gingipain-injected hyperglycemic group (OF + GP). At the end of 15 days, an oral glucose tolerance test (OGTT) was performed, and fasting blood glucose (FBG) levels were measured. Lipid peroxidation (LPO), nitric oxide (NO), glutathione (GSH), glutathione S-transferase, catalase, acetylcholinesterase (AChE), alkaline phosphatase (ALP), and sialic acid (SA) levels were determined spectrophotometrically in the hepatopancreas. The expression levels of tnf-⍺, il-1β, ins, crp, and the acute phase protein YKL-40 analogs chia.5 and chia.6 were evaluated by RT‒PCR. After two weeks of overfeeding, significantly increased weight gain, FBG, and OGTT confirmed that the zebrafish were hyperglycemic. Increased oxidative stress, inflammation, and AChE and ALP activities were observed in both the overfeeding and GP groups. Amplification of inflammation and oxidative stress was evident in the OF + GP group through increased expression of crp, il-1β, chia.5, and chia.6 and increased LPO and NO levels. Our results support the role of gingipains in the increased inflammatory response in hyperglycemia-associated diseases.

FCCP (carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone) is known to inhibit oxidative phosphorylation as a protonophore, dissipating the proton gradient across the inner mitochondrial membrane. To understand the toxicity of FCCP, 3-day, 2- and 4-week repeated oral dose studies were performed in male rats. In the 3-day and 2-week repeated dose toxicity studies, observations included salivation, increased body temperature, and dead and moribund animals. Increased liver weight was observed in conjunction with hydropic degeneration and centrilobular necrosis of hepatocytes. In addition, pathological changes were observed in the pancreas, testis, epididymal duct, stomach and parotid gland. Electron microscopic examination revealed mitochondrial pleomorphism in the hepatocytes. Swelling of mitochondria was observed in the alpha cells and beta cells of the pancreas. Dilatation of rough endoplasmic reticulum, Golgi bodies and loss of secretory granules were also noted in the beta cells of the pancreas. FCCP was also compared with three other mUncouplers (DNP, OPC-163493 and tolcapone) with regard to in vitro mitochondrial uncoupling (mUncoupling) activities. FCCP produced the peak ΔOCR (oxygen consumption rate) at the lowest concentration (0.4 μM), followed by OPC-163493, tolcapone, and DNP, based on peak values in ascending order of concentration (2.5, 10, and 50 μM, respectively). Considering the relationship between the mUncoupling activity and toxicity profile of the four mUncouplers, there is no parallel relationship between the in vitro mUncoupling activity and the degree of in vivo toxicity. These findings may contribute to the efficient development of new mitochondrial uncoupler candidates.

Supplementary information: The online version contains supplementary material available at 10.1007/s43188-023-00189-x.

We investigated the cytotoxic effect of Pelargonium sidoides extract on Madin-Darby canine kidney (MDCK) cells. P. sidoides extract decreased the cell viability in a dose dependent manner (> 0.2%). The extract of P. sidoides decreased the mitochondrial action potential, increased the number of reactive oxygen species (ROS) inside the cell, and caused nicotinamide adenine dinucleotide hydride (NADH) to be released, all of which are signs of mitochondrial dysfunction. The results of unbiased mRNA sequencing showed that 0.3% P. sidoides extract upregulates the apoptosis-related gene (BBC3). This finding was supported by immunoblot analysis of apoptosis signal pathways, which included Bcl-2, Bax, cytochrome C (CytC), cleaved caspase 3 (CC3), cleaved caspase 7 (CC7), cleaved caspase 9 (CC9) and cleaved PARP (CP). It is interesting to note that the elevated levels of Bax, CytC, CC3, CC7, and CC9, as well as CP, were suppressed by N-acetyl-L-cysteine (NAC) pretreatment, which points to ROS-mediated apoptosis. The small GTPases, RhoA, and Rac1/cdc42-GTP-bound active form were all lowered when P. sidoides extract was used. Also, RhoA-related cytoskeleton signals (ROCK, p-LIMK1/2, p-cofilin) and Rac1/cdc42-related signals (N-WASP, WAVE-2) were inhibited by P. sidoides extract. NAC or RhoA/Rac1/cdc42 activator pretreatment reduced P. sidoides extract-induced actin destabilization. In this work, P. sidoides extract promotes apoptosis by causing mitochondrial dysfunction and cytoskeleton disassembly.

This study characterised the changes in global gene expression in the lung of ICR mice in response to the inflammation and fibrosis induced by the inhalation of 0.5 μm polystyrene (PS)-nanoplastics (NPs) at various concentrations (4, 8, and 16 μg/mL) for 2 weeks. The total RNA extracted from the lung tissue of NPs-inhaled mice was hybridised into oligonucleotide microarrays. Significant upregulation was detected in several inflammatory responses, including the number of immune cells in bronchoalveolar lavage fluid (BALF), the expression level of inflammatory cytokines, mucin secretion, and histopathological changes, while they accumulated average of 13.38 ± 1.0 μg/g in the lungs of the inhaled ICR mice. Similar responses were observed regarding the levels of fibrosis-related factors in the NPs-inhaled lung of ICR mice, such as pulmonary parenchymal area, expression of pro-fibrotic marker genes, and TGF-β1 downstream signalling without any significant hepatotoxicity and nephrotoxicity. In microarray analyses, 60 genes were upregulated, and 55 genes were downregulated in the lung of ICR mice during inflammation and fibrosis induced by NPs inhalation compared to the Vehicle-inhaled mice. Among these genes, many were categorised into several ontology categories, including the anatomical structure, binding, membrane, and metabolic process. Furthermore, the major genes in the upregulated categories included Igkv14-126000, Egr1, Scel, Lamb3, and Upk3b. In contrast, the major genes in the down-regulated categories were Olfr417, Olfr519, Rps16, Rap2b, and Vmn1r193. These results suggest several gene functional groups and individual genes as specific biomarkers respond to inflammation and fibrosis induced by PS-NPs inhalation in ICR mice.

Supplementary information: The online version contains supplementary material available at 10.1007/s43188-023-00188-y.

Chronic exposure to Poly aromatic hydrocarbons (PAHs) may be associated with adverse pregnancy outcomes. Disruption of hormonal and redox balance by toxic PAH metabolites may interfere with successful pregnancy leading to miscarriage. The association of exposure to PAH contaminated mussel via the dietary route with perturbations in reproductive hormones, biomarkers of oxidative stress, and PAH metabolites were assessed in women with recurrent pregnancy loss (RPL). Furthermore, an analysis of the concentration of PAHs in environmentally relevant bivalve animals was performed to preliminary get insights into the levels of these pollutants in the environment. Seventy-six women (20-35 years) were categorized into 18 fertile women without RPL (control), and Groups I, II, and III comprising 24, 18, and 16 women with RPL (2, 3, and > 3 abortions respectively) were studied. Whole blood samples were collected for the estimation of malondialdehyde (MDA), catalase, reduced glutathione (GSH), glutathione-S-transferase (GST), progesterone (P4), follicle-stimulating hormone (FSH), benzo[a]pyren-7,8-dihydrodiol-9,10-epoxide-albumin adduct (BPDE-albumin) and urine for α-naphthol and β-naphthol. Two species of mussel Donax trunculus and Andar aduloii samples were collected for the estimation of 16 priority PAHs. The concentration of PAHs exceeding the maximum limits was observed in the two species of mussels studied. Higher levels of BPDE-albumin, MDA, GST, α and β-naphthol and lower GSH, catalase, FSH, and P4 were observed in women with RPL (Groups I-III) compared to controls (p =  < 0.001). Negative associations were observed between BPDE-albumin and catalase (r = - 0.276, p = 0.036), and GSH (r = - 0.331, p = - 0.011) only in women with RPL. Collectively, our findings indicate a possible association of chronic PAH accumulation with recurrent pregnancy loss in women.

Graphical abstract: High PAH exposure in pregnant women is associated with 10-epoxide-albumin adduct formation and high MDA levels in their sera. On the other hand, PAH exposure in those women led to a decrease in their GSH, catalase, P4, and FSH sera levels. These findings indicate that PAH exposure can exert different physiological effects in pregnant women leading to a high level of abortion in those women.

Some anthropogenic pollutants, such as heavy metals and nanoparticles (NPs), are widely distributed and a major threat to environmental safety and public health. In particular, lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), and mercury (Hg) have systemic toxicity even at extremely low concentrations, so they are listed as priority metals in relation to their significant public health burden. Aluminum (Al) is also toxic to multiple organs and is linked to Alzheimer's disease. As the utilization of many metal nanoparticles (MNPs) gradually gain traction in industrial and medical applications, they are increasingly being investigated to address potential toxicity by impairing certain biological barriers. The dominant toxic mechanism of these metals and MNPs is the induction of oxidative stress, which subsequently triggers lipid peroxidation, protein modification, and DNA damage. Notably, a growing body of research has revealed the linkage between dysregulated autophagy and some diseases, including neurodegenerative diseases and cancers. Among them, some metals or metal mixtures can act as environmental stimuli and disturb basal autophagic activity, which has an underlying adverse health effect. Some studies also revealed that specific autophagy inhibitors or activators could modify the abnormal autophagic flux attributed to continuous exposure to metals. In this review, we have gathered recent data about the contribution of the autophagy/mitophagy mediated toxic effects and focused on the involvement of some key regulatory factors of autophagic signaling during exposure to selected metals, metal mixtures, as well as MNPs in the real world. Besides this, we summarized the potential significance of interactions between autophagy and excessive reactive oxygen species (ROS)-mediated oxidative damage in the regulation of cell survival response to metals/NPs. A critical view is given on the application of autophagy activators/inhibitors to modulate the systematic toxicity of various metals/MNPs.