Ultralong AgNWs-induced toxicity in A549 cells and the important roles of ROS and autophagy

Emamectin benzoate-induced toxicity affects intestinal epithelial integrity involving apoptosis

The frequency presence of emamectin benzoate in agricultural production highlights the need for studying their toxicity against human intestinal epithelial barrier (IEB). Herein, we combined a Caco-2 cell model with transcriptome analysis to assess the intestinal toxicity of emamectin benzoate and its disease-causing potential. Results showed that the half maximal inhibitory concentration (IC50) of emamectin benzoate on Caco-2 cell viability after 24, 48, and 72 h of exposure were 18.1, 9.9, and 8.3 μM, respectively. Emamectin benzoate exposure enhanced the Caco-2 monolayer paracellular permeability, damaged the IEB, and increased cellular apoptosis. Key driver gene analysis of 42 apoptosis - related DEGs, identified 10 genes (XIAP, KRAS, MCL1, NRAS, PIK3CA, CYCS, MAPK8, CASP3, FADD, and TNFRSF10B) with the strongest correlation with emamectin benzoate - induced apoptosis. Transcriptomics identified 326 differentially expressed genes (DEGs, 204 upregulated and 122 downregulated). The functional terms of neurodegeneration - multiple diseases was enriched with the most number of DEGs, and the Parkinson disease pathway had the highest enrichment degree. Our findings provided support for environmental toxicology studies and the health risk assessment of emamectin benzoate.

Cellular absorption of polystyrene nanoplastics with different surface functionalization and the toxicity to RAW264.7 macrophage cells

Nanoplastics (NPs) are a matter of widespread concern, as they are easily absorbed by a wide variety of organisms and accumulate in biological tissues. While there is evidence that nanoplastics are toxic to various organisms, few studies have investigated the mechanisms underlying the toxicities of NPs with different surface functionalizations to macrophage cells. In this study, mouse mononuclear macrophage (RAW264.7) cells were exposed to polystyrene nanoplastics (PS-NPs) with three different surface functionalizations, namely pristine polystyrene (PS), carboxyl-functionalized polystyrene (PS-COOH), and amino-functionalized polystyrene (PS-NH₂), to evaluate the cellular endocytosis, lactate dehydrogenase (LDH) release, cell viability, reactive oxygen species (ROS), mitochondrial membrane potential, apoptosis, and related gene expression. Results showed that all three PS-NPs were endocytosed into cells. However, in the concentration range of 0-100 μg/mL, PS had no effect on cell viability or apoptosis, but it slightly increased cellular ROS and decreased mitochondrial membrane potential. PS-NH₂ exhibited the highest cytotoxicity. PS-COOH and PS-NH₂ induced ROS production, altered the mitochondrial membrane potential, and caused cell apoptosis regulated by the mitochondrial apoptosis pathway. Results also showed that cell membrane damage induced by PS-NH₂ is one of the primary mechanisms of its cytotoxicity to RAW264.7 cells. The results of this study clarify the toxicities of PS-NPs with different surface functionalizations to macrophages, thereby improving the identification of immune system risks related to nanoplastics.

Lipidomics analysis reveals new insights into the goose fatty liver formation

Our previous study described the mechanism of goose fatty liver formation from cell culture and transcriptome. However, how lipidome of goose liver response to overfeeding is unclear. In this study, we used the same batch of geese (control group and corn flour overfeeding group) to explore the lipidome changes and underlying metabolic mechanisms of goose fatty liver formation. Liquid chromatography-mass spectrometry (LC-MS) was provided to lipidome detection. Liver lipidomics profiles analysis was performed by principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA), different lipids were identified and annotated, and the enriched metabolic pathways were showed. The results of PCA, PLS-DA, and OPLS-DA displayed a clear separation and discrimination between control group and corn flour overfeeding group. Two hundred and fifty-one different lipids were yielded, which were involved in triglyceride (TG), diglyceride (DG), phosphatidic acids (PA), phosphatidylinositols (PI), phosphatidylethanolamines (PE), phosphatidylcholines (PC), lyso-phosphatidylcholines (LPC), monogalactosylmonoacylglycerol (MGMG), sphingolipids (SM), ceramides (Cer), and hexaglycosylceramides (Hex1Cer). Different lipids were enriched in glycerophospholipid metabolism, glycerolipid metabolism, phosphatidylinositol signaling system, inositol phosphate metabolism, glycosylphosphatidylinositol (GPI)-anchor biosynthesis and sphingolipid metabolism. In conclusion, this is the first report describing the goose fatty liver formation from lipidomics, this study might provide some insights into the underlying glucolipid metabolism disorders in the process of fatty liver formation.

Silver Nanoparticles Induce Apoptosis in HepG2 Cells through Particle-Specific Effects on Mitochondria

Silver nanoparticles (AgNPs) have been widely used in biomedical and consumer products. It remains challenging to distinguish the toxicity of AgNPs derived from the particle form or the released silver ions (Ag⁺). In this study, the toxic effects of two citrate-coated AgNPs (20 and 100 nm) and Ag⁺ were investigated in hepatoblastoma cells (HepG2 cells). The suppression tests showed that AgNPs and Ag⁺ induced cell apoptosis via different pathways, which led us to speculate on the AgNP-induced mitochondrial damage. Then, the mitochondrial damages induced by AgNPs and Ag⁺ were compared under the same intracellular Ag⁺ concentration, showing that the mitochondrial damage might be mainly attributed to Ag nanoparticles but not to Ag⁺. The interaction between AgNPs and mitochondria was analyzed using a scattered light imaging method combined with light intensity profiles and transmission electron microscopy. The colocalization of AgNPs and mitochondria was observed in both NP20- and NP100-treated HepG2 cells, indicating a potential direct interaction between AgNPs and mitochondria. These results together showed that AgNPs induced apoptosis in HepG2 cells through the particle-specific effects on mitochondria.

Mucin1 relieves acute lung injury by inhibiting inflammation and oxidative stress

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a kind of diffuse inflammatory injury caused by various factors, characterized by respiratory distress and progressive hypoxemia. It is a common clinical critical illness. The aim of this study was to investigate the effect and mechanism of the Mucin1 (MUC1) gene and its recombinant protein on lipopolysaccharide (LPS)-induced ALI/ARDS. We cultured human alveolar epithelial cell line (BEAS-2B) and used MUC1 overexpression lentivirus to detect the effect of MUC1 gene on BEAS-2B cells. In addition, we used LPS to induce ALI/ARDS in C57/BL6 mice and use hematoxylin and eosin (H&E) staining to verify the effect of their modeling. Recombinant MUC1 protein was injected subcutaneously into mice. We examined the effect of MUC1 on ALI/ARDS in mice by detecting the expression of inflammatory factors and oxidative stress molecules in mouse lung tissue, bronchoalveolar lavage fluid (BALF) and serum. Overexpression of MUC1 effectively ameliorated LPS-induced damage to BEAS-2B cells. Results of H&E staining indicate that LPS successfully induced ALI/ARDS in mice and MUC1 attenuated lung injury. MUC1 also reduced the expression of inflammatory factors (IL-1β, TNF-α, IL-6 and IL-8) and oxidative stress levels in mice. In addition, LPS results in an increase in the activity of the TLR4/NF-κB signaling pathway in mice, whereas MUC1 decreased the expression of the TLR4/NF-κB signaling pathway. MUC1 inhibited the activity of TLR4/NF-κB signaling pathway and reduced the level of inflammation and oxidative stress in lung tissue of ALI mice.

Nonspherical Metal-Based Nanoarchitectures: Synthesis and Impact of Size, Shape, and Composition on Their Biological Activity

Metal-based nanoentities, apart from being indispensable research tools, have found extensive use in the industrial and biomedical arena. Because their biological impacts are governed by factors such as size, shape, and composition, such issues must be taken into account when these materials are incorporated into multi-component ensembles for clinical applications. The size and shape (rods, wires, sheets, tubes, and cages) of metallic nanostructures influence cell viability by virtue of their varied geometry and physicochemical interactions with mammalian cell membranes. The anisotropic properties of nonspherical metal-based nanoarchitectures render them exciting candidates for biomedical applications. Here, the size-, shape-, and composition-dependent properties of nonspherical metal-based nanoarchitectures are reviewed in the context of their potential applications in cancer diagnostics and therapeutics, as well as, in regenerative medicine. Strategies for the synthesis of nonspherical metal-based nanoarchitectures and their cytotoxicity and immunological profiles are also comprehensively appraised.

Hexavalent chromium induces renal apoptosis and autophagy via disordering the balance of mitochondrial dynamics in rats

The use of hexavalent chromium (Cr(VI)) in many industrial processes has resulted in serious environmental pollution problems. Cr(VI) causes organ toxicity in animals after ingestion or inhalation. However, the exact mechanism by which Cr(VI) produces kidney damage remains elusive. Herein, we investigated whether Cr(VI)-induced kidney damage is related to the disorder of mitochondrial dynamics. In this study, 28 male rats were divided into four groups and intraperitoneally injected with 0, 2, 4, and 6 mg/kg body weight potassium dichromate for 5 weeks. Experiment included analysis of renal histopathology and ultrastructure, determination of biochemical indicators, and measurement of related protein content. The results showed that Cr(VI) induced kidney injury through promotion of oxidative stress, apoptosis, and disorder of mitochondrial dynamics in a dose-dependent manner. The protein levels of the silent information regulator two ortholog 1 (Sirt1), peroxisome proliferation-activated receptor-g coactivator-1a (PGC-1a), and autophagy-related proteins were significantly decreased after Cr(VI) exposure. These findings suggest that Cr(VI) leads to the disorder of mitochondrial dynamics by inhibiting the Sirt1/PGC-1a pathway, which leads to renal apoptosis and autophagy in rats.

N-doped carbon dots triggered the induction of ROS-mediated cytoprotective autophagy in Hepa1-6 cells

Carbon dots (CDs) are an emerging fluorescent nano-imaging probe due to their unique characteristics, such as good conductivity, carbon-based chemical composition, and photochemical stability, which sets up the potential of outperforming the classic metal-based quantum dots (QDs). It is a timely effort to proactively investigate the biocompatibility feature of CDs with a view to safely utilize this emerging nanomaterial in biological systems. In this study, we assessed the safety profile of an in-house synthesized CDs in hepatocyte-like Hepa 1-6 cells, which represents an important target organ for CDs exposure through either particle uptake and/or accumulation and elimination from primary exposure sites post particle administration. We not only demonstrated a dose- and time-dependent compromised cell viability, but also observed the induction of autophagy at high concentration (i.e. 400 μg mL-1), authenticated by the conversion of microtubule-associated protein light chain 3 (LC3)-I to LC3-II. We attributed these changes as the protective mechanism by which the cells used to compensate for CDs-induced apoptosis and cytotoxicity. The involvement of autophagy was further confirmed because the cytotoxicity profile can be increased or reduced by the use of 3-MA (autophagy inhibitor) and NAC (ROS inhibitor), respectively. Collectively, our findings revealed dose-dependent moderate cytotoxicity in Hepa 1-6 cells. Mechanistic understanding of autophagy during the cellular process revealed the homeostasis when liver cells deal with CDs as an external insult.

13-Methylberberine improves endothelial dysfunction by inhibiting NLRP3 inflammasome activation via autophagy induction in human umbilical vein endothelial cells

Background

Atherosclerosis, the underlying cause of the majority of cardiovascular diseases, is a lipid-driven, inflammatory disease of the large arteries. Atherosclerotic cardiovascular disease (ASCVD) threatens human lives due to high morbidity and mortality. Many studies have demonstrated that atherosclerosis is accelerated via activation of the NLRP3 inflammasome. The NLRP3 inflammasome plays a critical role in the development of vascular inflammation and atherosclerosis. In atherosclerotic plaques, excessive generation of reactive oxygen species (ROS) activates the NLRP3 inflammasome. 13-Methylberberine (13-MB) is a newly synthesized compound used in traditional Chinese medicine that has outstanding antibacterial, antitumor, and antiobesity activities, especially anti-inflammatory activity. However, the role of 13-MB in atherosclerosis needs to be explored.

Methods

CCK-8 assays and flow cytometry were conducted to determine the cell viability and apoptotic profiles of human umbilical vein endothelial cells (HUVECs) treated with 13-MB. Carboxy-DCFH-DA and JC-10 assays were used to measure ROS and determine mitochondrial membrane potential. Western blot analysis was performed to investigate proteins that are associated with the NLRP3 inflammasome and autophagy. ELISA was used to detect and quantify inflammatory cytokines related to the NLRP3 inflammasome. Transfection and confocal microscopy were conducted to observe autophagy.

Results

Pretreatment with 13-MB markedly reduced cytotoxicity and apoptosis, as well as intracellular ROS production, in H₂O₂-induced HUVECs. Moreover, 13-MB showed a protective effect in maintaining mitochondrial membrane potential. 13-MB also suppressed NLRP3 inflammasome activation and promoted autophagy induction in HUVECs.

Conclusion

13-MB exerts cytoprotective effects in an H₂O₂-induced cell injury model by inhibiting NLRP3 inflammasome activation via autophagy induction in HUVECs. These anti-inflammatory and autophagy induction activities may provide valuable evidence for further investigating the potential role of 13-MB in atherosclerosis.