Toxicology and applied pharmacology最新文献

Acute lung injury (ALI) is characterized by hyperinflammation followed by vascular leakage and respiratory failure. Vascular endothelial growth factor (VEGF)-A is critical for capillary permeability; however, the role of VEGF receptor 1 (VEGFR1) signaling in ALI progression remains unclear. Here, we show that deletion of VEGFR1 tyrosine kinase (TK) signaling in mice exacerbates lipopolysaccharide (LPS)-induced ALI as evidenced by excessive pro-inflammatory cytokine production and interleukin(IL)-1β-producing neutrophil recruitment to inflamed lung tissues. ALI development involves reduced alveolar macrophage (AM) levels and recruitment of monocyte-derived macrophages (MDMs) in a VEGFR1 TK-dependent manner. VEGFR1 TK signaling reduced pro-inflammatory cytokine levels in cultured AMs. VEGFR1 TK-expressing MDMs displayed an anti-inflammatory macrophage phenotype. Additionally, the transplantation of VEGFR1 TK-expressing bone marrow (BM)-derived macrophages into VEGFR1 TK-deficient mice reduced lung inflammation. Treatment with placental growth factor (PlGF), an agonist for VEGFR1, protected the lung against LPS-induced ALI associated with increased MDMs. These results suggest that VEGFR1 TK signaling prevents LPS-induced ALI by suppressing the pro-inflammatory activity of AMs and enhancing the anti-inflammatory function of MDMs.

Fatty acid-binding proteins (FABPs) are small intracellular proteins that regulate fatty acid metabolism, transport, and signalling. There are ten known human isoforms, many of which are upregulated and involved in clinical pathologies. As such, FABP inhibition may be beneficial in disease states such as cancer, and those involving the cardiovascular system, metabolism, immunity, and cognition. Recently, a potent, selective FABP5 inhibitor (ART26.12), with 90-fold selectivity to FABP3 and 20-fold selectivity to FABP7, was found to be remarkably benign, with a no-observed-adverse-effect level of 1000 mg/kg in rats and dogs, showing no genotoxicity, cardiovascular, central, or respiratory toxicity. To understand the potential implication of FABP inhibition more fully, this review systematically assessed literature investigating genetic knockout, knockdown, and pharmacological inhibition of FABP3, FABP4, FABP5, or FABP7. Analysis of the literature revealed that animals bred not to express FABPs showed the most biological effects, suggesting key roles of these proteins during development. FABP ablation sometimes exacerbated symptoms of disease models, particularly those linked to metabolism, inflammatory and immune responses, cardiac contractility, neurogenesis, and cognition. However, FABP inhibition (genetic silencing or pharmacological) had a positive effect in many more disease conditions. Several polymorphisms of each FABP gene have also been linked to pathological conditions, but it was unclear how several polymorphisms affected protein function. Overall, analysis of the literature to date suggests that pharmacological inhibition of FABPs in adults is of low risk.

The survival rates for patients with osteosarcoma (OS) have stagnated over the past few decades. It is essential to find new therapies and drugs. A licensed antipsychotic medication called trifluoperazine (TFP) significantly reduces the growth of several cancers. However, the exact molecular pathways of TFP in OS remain to be discovered. Our research revealed that TFP greatly reduced OS cell migration and growth and caused the arrest of G0/G1 cell cycle. Combined with RNA-Seq data and further research, we confirmed that TFP promoted reactive oxygen species (ROS) production by elevating thioredoxin binding protein (TXNIP) expression to induce mitochondria-dependent apoptosis. Interestingly, we first demonstrated that AKT was an upstream regulatory target of TXNIP in OS cells. Dephosphorylation of AKT led to an increase in TXNIP expression, further elucidating the anticancer mechanism of TFP. In vivo, TFP inhibited subcutaneous OS cell proliferation and induced OS cell apoptosis without noticeable side effects. In conclusion, our findings imply that TFP is a potential treatment for OS.

Purpose

Doxorubicin is an antibiotic drug used clinically to treat infectious diseases and tumors. Unfortunately, it is cardiotoxic. Autophagy is a cellular self-decomposition process that is essential for maintaining homeostasis in the internal environment. Accordingly, the present study was proposed to characterize the autophagy-related signatures of doxorubicin-induced cardiotoxicity.

Methods

Datasets related to doxorubicin-induced cardiotoxicity were retrieved by searching the GEO database and differentially expressed genes (DEGs) were identified. DEGs were taken to intersect with autophagy-related genes to obtain autophagy-related signatures, and Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and protein-protein interaction (PPI) network were performed on them. Further, construction of miRNA-hub gene networks and identification of target drugs to reveal potential molecular mechanisms and therapeutic strategies. Animal models of doxorubicin-induced cardiotoxicity were constructed to validate differences in gene expression for autophagy-related signatures.

Results

PBMC and heart samples from the GSE37260 dataset were selected for analysis. There were 995 and 2357 DEGs in PBMC and heart samples, respectively, and they had 23 intersecting genes with autophagy-related genes. RT-qPCR confirmed the differential expression of 23 intersecting genes in doxorubicin-induced cardiotoxicity animal models in general agreement with the bioinformatics results. An autophagy-related signatures consisting of 23 intersecting genes is involved in mediating processes and pathways such as autophagy, oxidative stress, apoptosis, protein ubiquitination and phosphorylation. Moreover, Akt1, Hif1a and Mapk3 are hub genes in autophagy-associated signatures and their upstream miRNAs are mainly rno-miR-1188-5p, rno-miR-150-3p and rno-miR-326-3p, and their drugs are mainly CHEMBL55802, Carboxyamidotriazole and 3-methyladenine.

Conclusion

This study identifies for the first-time autophagy-related signatures in doxorubicin's cardiotoxicity, which could provide potential molecular mechanisms and therapeutic strategies for doxorubicin-induced cardiotoxicity.

The endocannabinoid system plays an important role in the regulation of metabolism, growth and regeneration of peripheral tissues, including liver, adipose and muscle tissue. Studies in cells, rodents and humans showed that cannabinoid receptor 1 (CB₁) antagonist treatment is an effective strategy to improve features of metabolic health such as substrate metabolism, at least in models of metabolic dysregulation. However, acute signaling events that might induce these metabolic adaptations are not understood. It is not clear whether, and to which extent, a single treatment with a CB₁ antagonist induces acute effects in peripheral, metabolic tissues. Therefore, the present study compared the phosphorylation status of signaling pathways and metabolic markers in liver, adipose and muscle tissue of mice treated with the peripherally restricted CB₁ antagonist AM6545 and vehicle-treated mice. Protein kinase A phosphorylation was downregulated in white and brown adipose tissue, whereas the mitogen-activated protein kinase, phospho-extracellular signal-regulated kinase, was higher in liver, white adipose and muscle tissue of AM6545-treated mice. Additionally, Akt-mammalian target of rapamycin activation was higher in all tissues of AM6545-treated mice, whereas the phosphorylation status of metabolic markers remained unaffected. These data indicate that acute CB₁ antagonism is effective to induce phosphorylation events of signaling cascades and metabolic markers in metabolic tissues of healthy, lean mice within a 90-min time window. The observed adaptations to AM6545 treatment do not fully align with earlier in vitro and in vivo findings, which could be ascribed to differences in cell type, exposure intensity (dose and time), health status and species.

RUNX1 with CBFβ functions as an activator or repressor of critical mediators regulating cellular function. The aims of this study were to clarify the role of RUNX1 on regulating TGF-β1-induced COL1 synthesis and the mechanism of calcipotriol (Cal) on antagonizing COL1 synthesis in PSCs. RT-qPCR and Western Blot for determining the mRNAs and proteins of RUNX1 and COL1A1/1A2 in rat PSC line (RP-2 cell). Luciferase activities driven by RUNX1 or COL1A1 or COL1A2 promoter, co-immunoprecipitation and immunoblotting for pSmad3/RUNX1 or CBFβ/RUNX1, and knockdown or upregulation of Smad3 and RUNX1 were used. RUNX1 production was regulated by TGF-β1/pSmad3 signaling pathway in RP-2 cells. RUNX1 formed a coactivator with CBFβ in TGF-β1-treated RP-2 cells to regulate the transcriptions of COL1A1/1A2 mRNAs under a fashion of pSmad3/RUNX1/CBFβ complex. However, Cal effectively abrogated the levels of COL1A1/1A2 transcripts in TGF-β1-treated RP-2 cells by downregulating RUNX1 production and hindering the formation of pSmad3/RUNX1/CBFβ complexes. This study suggests that RUNX1 may be a promising antifibrotic target for the treatment of chronic pancreatitis.

Benzene is a common contaminant in the workplace and wider environment, which induces hematotoxicity. Our previous study has implicated that lncRNAs mediated apoptosis and autophagy induced by benzene. Nevertheless, the roles of extracellular vesicle(EVs)-derived lncRNAs in benzene toxicity are unknown. However, the role of EVs and EVs-derived lncRNAs in benzene-induced toxicity remains unclear. In this research, we explored the function of EVs and EVs-derived lncRNAs in cell-cell communication through benzene-induced apoptosis and autophagy. Our findings demonstrated that EVs derived from 1,4-BQ-treated cells treated cells and coculture with 1,4-BQ-treated cells enhanced apoptosis and autophagy via regulating the pathways of PI3K-AKT-mTOR and chaperone-mediated autophagy. Treating with GW4869 in 1,4-BQ-treated cells significantly inhibited EV secretion, which reduced apoptosis and autophagy. Furthermore, we identified a set of differentially expressed autophagy- and apoptosis-related lncRNAs using EVs-derived lncRNA sequencing. Among them, 8 candidate lncRNAs were upregulated in EVs derived from 1,4-BQ-treated cells, as determined by lncRNA sequencing and qRT–PCR. Importantly, these lncRNAs were also increased in the serum EVs of benzene-exposed workers. 1,4-BQ-treated cells released EVs that transfer differentially expressed lncRNAs, thereby inducing apoptosis and autophagy in the recipient cells. The above results support the hypothesis that EVs-derived lncRNAs participate in intercellular communication during benzene-induced hematotoxicity and function as potential biomarkers for risk assessment of benzene-exposed workers.

Background

Celastrol is a natural triterpene exhibiting significant and extensive antitumor activity in a wide range of cancer. Due to unfavorable toxicity profile and undefined mechanism, Celastrol's application in clinical cancer therapy remains limited. Herein, we elucidate the pharmacological mechanism of Celastrol's anticancer effects, with a focus on STAT3 signaling pathway in cancers with high incidence of metastasis.

Methods

The safety profile of Celastrol were assessed in mice. In vitro analysis was performed in gastric cancer and ovarian cancer to assess the cytotoxicity, induction of reactive oxygen species (ROS) of Celastrol using STAT3 knockout cancer cells. Effects of Celastrol on STAT3 activation and transcription activity, JAK2/STAT3 signaling protein expression were assessed. Additionally, proteomic contrastive analysis was performed to explore the molecular association of Celastrol with STAT3 deletion in cancer cells.

Results

Celastrol has no obvious toxic effect at 1.5 mg/kg/day in a 15 days' administration. Celastrol inhibits tumor growth and increases ROS in a STAT3 dependent manner in gastric and ovarian cancer celllines. On molecular level, it downregulates IL-6 level and inhibits the JAK2/STAT3 signaling pathway by suppressing STAT3’ activation and transcription activity. Proteomic contrastive analysis suggests a similar cellular mechanism of action between Celastrol and STAT3 deletion on regulating cancer progression pathways related to migration and invasion.

Conclusion

Our research elucidates the anti-cancer mechanism of Celastrol through targeting the JAK2/STAT3 signaling pathway in cancer with high incidence of metastasis. This study provides a solid theoretical basis for the application of Celastrol in cancer therapy.

Artesunate (ART) is a derivative of artemisinin and has anti-inflammatory, anti-tumor, and anti-angiogenic properties. Although ART has been implicated in osteoarthritis (OA), the mechanism needs to be further dissected. Here, we explored the effects of ART on the development of OA and the underlying mechanism using destabilization of the medial meniscus (DMM) surgical instability model. Mice with OA were developed using DMM and treated with ART. The pathological morphology of knee joint tissues was examined, and the degeneration of joint cartilage was assessed. Mouse knee chondrocytes were isolated and induced with IL-1β, followed by ART treatment. ART alleviates OA in mice by elevating ubiquitin carboxyl-terminal hydrolase 7 (USP7) expression, and USP7 inhibitor (P22077) treatment mitigated the protective effects of ART on chondrocytes. We also showed that USP7 mediated the deubiquitination of forkhead box protein O1 (FoxO1), while FoxO1 alleviated chondrocyte injury. In addition, FoxO1 promoted metastasis-associated protein MTA1 (MTA1) transcription, and downregulation of MTA1 exacerbated chondrocyte injury. Our study identifies that USP7/FoxO1/MTA1 is a key signaling cascade in the treatment of ART on OA.

Despite its efficacy in human epidermal growth factor receptor 2 positive cancer treatment, trastuzumab-induced cardiotoxicity (TIC) has become a growing concern. Due to the lack of cardiomyocyte regeneration and proliferation in adult heart, cell death significantly contributes to cardiovascular diseases. Cardiac autonomic modulation by vagus nerve stimulation (VNS) has shown cardioprotective effects in several heart disease models, while the effects of VNS and its underlying mechanisms against TIC have not been found. Forty adult male Wistar rats were divided into 5 groups: (i) control without VNS (CSham) group, (ii) trastuzumab (4 mg/kg/day, i.p.) without VNS (TSham) group, (iii) trastuzumab + VNS (TVNS) group, (iv) trastuzumab + VNS + mAChR blocker (atropine; 1 mg/kg/day, ip, TVNS + Atro) group, and (v) trastuzumab + VNS + nAChR blocker (mecamylamine; 7.5 mg/kg/day, ip, TVNS + Mec) group. Our results showed that trastuzumab induced cardiac dysfunction by increasing autonomic dysfunction, mitochondrial dysfunction/dynamics imbalance, and cardiomyocyte death including apoptosis, autophagic deficiency, pyroptosis, and ferroptosis, which were notably alleviated by VNS. However, mAChR and nAChR blockers significantly inhibited the beneficial effects of VNS on cardiac autonomic dysfunction, mitochondrial dysfunction, cardiomyocyte apoptosis, pyroptosis, and ferroptosis. Only nAChR could counteract the protective effects of VNS on cardiac mitochondrial dynamics imbalance and autophagy insufficiency. Therefore, VNS prevented TIC by rebalancing autonomic activity, ameliorating mitochondrial dysfunction and cardiomyocyte death through mAChR and nAChR activation. The current study provides a novel perspective elucidating the potential treatment of VNS, thus also offering other pharmacological therapeutic promises in TIC patients.