Cell Biology and Toxicology最新文献

Engineered nanoparticles (ENPs), defined as nanoscale materials with at least one dimension between 1 and 100 nm, exhibit multifunctional and tunable physicochemical properties, that are at the center of several innovative fields. However, ENPs may induce a variety of biochemical reactions upon entry into organisms that could be a threat to human health. Therefore, a systematic evaluation of the toxicity of ENPs is essential. Quantitative structure-activity relationship (QSAR) is a practical in vitro modeling approach used to evaluate the toxicity of nanoparticles. In this study, we established the nanometric QSAR (Nano-QSAR) modelling based on cell membrane damage of ENPs to HepaRG cells. The toxicity data of ENPs and related 2D descriptor information were collected from the NanoCommons Knowledge Base. Periodic table descriptors of the elements were calculated using the Elemental Descriptor Calculator software. A multiple linear regression (MLR) model was constructed, and subsequently combined with read-across (RA) descriptors to establish the Nano-quantitative read-across structure-activity relationship (Nano-q-RASAR) model. Furthermore, machine learning (ML) algorithms were applied to optimize the predictive performance of the models. All models were validated according to the stringent OECD QSAR validation guidelines. Finally, a series of true external ENPs without experimental values were autonomously designed, and predicted using the best GB-Nano-QSAR model. Overall, this study can provide efficient and reliable predictions for the cell membrane damage of ENPs and a detailed theoretical explanation of their toxicity mechanism, which is of practical value for the toxicity assessment of ENPs.

Acute myeloid leukemia (AML)-derived bone mesenchymal stem cell (MSC) exosomes have been confirmed to have a positive effect on AML progression. This study aim to reveal the underlying molecular mechanism by which AML-MSC-derived exosomes promotes AML progression. AML-MSC was isolated from the bone marrow aspirates of AML patients. After incubated with AML-MSC, AML cell functions were analyzed. The expression levels of methyltransferase-like 14 (METTL14), homeobox A3 (HOXA3), WNT family member 7B (WNT7B) and glycolysis-related markers were examined. Exosomes were isolated from AML-MSC and then the obtained exosomes were co-cultured with AML cells. AML-MSC co-culturing could enhance AML cell proliferation and glycolysis, while repress cell apoptosis. METTL14 was upregulated in exosomes from AML-MSC, which could be ingested by AML cells. METTL14 could enhance HOXA3 mRNA stability via promoting its m6A modification. Knockdown of exosomal METTL14 from AML-MSC inhibited AML cell growth and glycolysis, while were reversed by HOXA3. In addition, HOXA3 bound to WNT7B promoter to increase its transcription, and WNT7B overexpression also eliminated si-HOXA3-mediated inhibitory on AML cell growth and glycolysis. Animal study revealed that knockdown of exosomal METTL14 from AML-MSC reduced AML tumorigenesis by decreasing HOXA3 and WNT7B expression. AML-MSC-derived exosomal METTL14 facilitated AML cell growth and glycolysis by activating the HOXA3/WNT7B axis, providing a new mechanism for understanding AML-MSC-derived exosomes to promote AML progression.

Colorectal cancer (CRC) remains one of the leading causes of cancer-related deaths worldwide, largely due to late-stage diagnosis and limited efficacy of current therapies. 5-Fluorouracil (5-FU) is the standard chemotherapeutic agent used in CRC treatment; however, its effectiveness is often hampered by resistance, toxicity, and suboptimal outcomes in advanced-stage tumors. Recent evidence suggests that gut microbiota-derived short-chain fatty acids (SCFAs) exert anticancer effects and may hold promise as therapeutic adjuvants. In this study, we investigated the potential of a physiologically relevant mixture of SCFAs to enhance the efficacy of 5-FU against CRC. Using a combination of 2D monolayer cultures, 3D models, and the in vivo chicken chorioallantoic membrane (CAM) assay, we demonstrated that SCFAs positively affect the antitumor effects of low-dose 5-FU. SCFAs contributed to the inhibition of CRC cell growth, proliferation, survival, and migration, with an overall increase of the anti-tumour effects observed across the different models. The combined treatment led to a significant reduction in tumour size in the CAM assay, contributing for an improvement of the effects of 5-FU alone. To our knowledge, this is the first report showing that physiologically relevant SCFA combinations can be harnessed to improve the therapeutic index of 5-FU in CRC, in a context-dependent manner. These findings support the development of microbiota-targeted co-adjuvant strategies to optimize CRC chemotherapy, reduce treatment toxicity, and improve patient outcomes, which is important given the clinical interest in microbiome-chemotherapy interactions.

Alzheimer's disease (AD) is a heterogeneous disease with limited treatment efficacy. Identifying novel molecular targets and mechanisms is therefore crucial for developing therapeutic strategies. Zinc finger protein 36 (ZFP36) has not been reported in AD. This study found that the hippocampus of APP/PS1 mice showed ZFP36 upregulation. Using recombinant adeno-associated virus to overexpress ZFP36 improved the cognitive function of APP/PS1 mice, as assessed by Morris maze and Y maze tests. Furthermore, ZFP36 overexpression reduced Aβ deposition, expression of pro-inflammatory markers, and inhibited NLRP3 inflammasome activation in the hippocampus. These inhibitory effects of ZFP36 overexpression on the aforementioned proteins were also observed in Aβ₁₋₄₂-treated BV-2 cells. mRNA sequencing identified Z-DNA Binding Protein 1 (ZBP1) as a target of ZFP36. After ZFP36 overexpression, ZBP1 was downregulated in the hippocampus and Aβ_1-42-treated BV-2 cells. The interaction between ZFP36 and ZBP1 RNA was verified by RIP-PCR, and ZFP36 was shown to promote the degradation of ZBP1 mRNA. The inhibitory effects of ZFP36 on the NLRP3 inflammasome activation and microglial pro-inflammatory activation was reversed by ZBP1 overexpression. In summary, ZFP36 inhibits microglia pro-inflammatory and NLRP3 inflammasome activation through promoting the degradation of ZBP1 mRNA, thereby ameliorating cognitive deficits of APP/PS1 mice.

Objective: Tubal factor infertility (TFI), a major cause of female infertility, lacks effective therapies and is closely associated with macrophage-mediated inflammation. Although DDX3X regulates macrophage polarization, its specific contribution to TFI pathogenesis remains unclear, and the potential involvement of E3 ubiquitin ligase-mediated regulation of DDX3X protein stability in this condition has not been reported. Therefore, our study planned to explore the regulation of DDX3X by the E3 ubiquitin ligase TRIM36 and how this axis influences macrophage polarization and TFI pathogenesis.

Methods: The GSE262037 dataset and the STRING platform were analyzed through bioinformatics approaches to identify TRIM36, an E3 ubiquitin ligase of DDX3X. A mixed bacterial inoculation method was employed to establish a TFI model of rats, and the animals were treated with TRIM36 overexpression (oe-TRIM36). Stimulation of LPS in the fallopian tube epithelial cells was applied to establish the in vitro TFI model, which was treated by the conditioned medium (CM) from rat bone marrow-derived macrophages (BMDM) with LPS, silence (si)/oe-DDX3X, and/or oe-TRIM36 treatment. Co-Immunoprecipitation (Co-IP) detection was employed to analyze the regulation of si/oe-TRIM36 on the ubiquitination of DDX3X protein.

Results: DDX3X expression was significantly upregulated in TFI rats and showed a positive correlation with M1 macrophage polarization. Silencing DDX3X in rat BMDM promoted M2 polarization while suppressing M1 polarization, and the CM derived from these macrophages alleviated LPS-induced damage in fallopian tube epithelial cells. Bioinformatics and Co-IP identified TRIM36 as an E3 ubiquitin ligase binding DDX3X, and TRIM36 overexpression promoted the K48-linked polyubiquitination and the proteasomal degradation of DDX3X. Similarly, TRIM36-mediated DDX3X downregulation shifted macrophage polarization towards the M2 phenotype in vitro and protected fallopian tube epithelial cells against LPS-induced damage. Importantly, in vivo oe-TRIM36 therapy downregulated DDX3X, increased M2 macrophages, reduced tubal inflammation, and significantly alleviated infertility phenotypes in TFI model rats.

Conclusion: This study identifies TRIM36 as a novel E3 ligase that targets DDX3X for proteasomal degradation, thereby driving macrophage M2 polarization and ameliorating TFI. The TRIM36/DDX3X axis may provide a promising therapeutic target for TFI treatment.

Humans are continuously exposed to a wide array of exogenous chemicals via dietary intake, environmental sources, and the use of personal care products. This includes per- and polyfluoroalkyl substances (PFAS), a class of highly persistent compounds that have been associated with developmental effects in humans. This study assessed the effects of four legacy PFAS, namely PFOS, PFOA, PFNA and PFHxS, and mixtures thereof in the PluriLum assay, a 3D human induced pluripotent stem cell (hiPSC)-based model for embryotoxicity testing. We established the individual embryotoxic potencies of PFAS, with PFNA exhibiting the highest potency, followed by PFOS, PFOA and PFHxS. The four PFAS were evaluated in three reconstituted mixtures, prepared either to reflect identical potencies ("equipotent mixture") or the average serum concentrations reported for the European adult or child population ("real-life mixtures"). Comparing observed versus predicted mixture responses demonstrated concentration additivity throughout the entire range of tested concentrations. Studies on uptake in 3D embryoid bodies revealed the highest bioaccumulation of PFOS, followed by PFNA, PFOA, and PFHxS. Moreover, less than 2% of the nominally added PFAS could be recovered in the embryoid bodies. RNA sequencing showed that relatively few genes were affected by PFOS, PFNA and PFOA, however expression of genes related to focal adhesion and functional pathways associated with cardiac, cardiomyocyte and muscle tissue development was significantly changed. Notably, PFOS affected the greatest number of embryonic development pathways. In conclusion, the four tested PFAS significantly impaired cardiomyocyte differentiation, indicating embryotoxicity. The combined responses were consistent with the concentration addition principle, supported by shared functional pathways and indicative of common sites of molecular action.

Metabolic dysfunction-associated steatohepatitis (MASH) drives hepatic stellate cell (HSC) activation and extracellular matrix deposition, leading to liver fibrosis, for which effective treatments remain lacking. Here, we report that 8-hydroxyoctacosatrienoic acid (8-HETrE), an arachidonic acid metabolite generated through cytochrome P450 or lipoxygenase pathways, significantly ameliorates MASH-related fibrosis by targeting sphingosine kinase 1 (SPHK1) and restoring mitochondrial function. Clinical observations revealed markedly reduced circulating 8-HETrE levels in patients with MASH fibrosis. In vivo studies demonstrated that 8-HETrE administration improved liver function, enhanced expression of mitochondrial fusion proteins (Mfn1, Mfn2, Opa1), and attenuated fibrosis in Gubra-Amylin-NASH (GAN)-diet-induced MASH models. In TGF-β1-activated human HSCs cell line (LX-2 cells), 8-HETrE treatment suppressed fibrotic markers (α-SMA, COL1A1) and improved mitochondrial dynamics. Mechanistic investigations revealed that 8-HETrE exerted its anti-fibrotic effects primarily through SPHK1 inhibition: SPHK1 knockdown moderately reduced HSC activation, decreased sphingosine-1-phosphate (S1P), lactate, and nitrite levels, enhanced glucose uptake, and promoted mitochondrial fusion, while completely abolishing 8-HETrE's therapeutic effects. Conversely, SPHK1 overexpression exacerbated fibrotic and metabolic abnormalities, which were effectively reversed by 8-HETrE treatment. Critically, HSC-specific Sphk1 knockout independently improved MASH fibrosis, mitochondrial function, and metabolic parameters, while completely blocking 8-HETrE's benefits. Our findings identify 8-HETrE as a novel mediator that targets the SPHK1-mitochondrial dynamics axis in HSCs, providing both mechanistic insights and therapeutic potential for MASH-related fibrosis treatment.

Nanoplastics (NPs, < 1 µm) are emerging environmental contaminants capable of crossing biological barriers and interacting at the cellular and subcellular level. Despite evidence of microplastics in human kidney tissue and urine, the renal effects of NPs remain poorly understood. This study investigated the short-term effects of NPs polymer type, size, and concentration on human kidney proximal tubule cells (HK-2). Cells were exposed for 24-h to carboxylated polystyrene (PS), poly(methyl methacrylate) (PMMA), and polyethylene (PE) NPs (15-100 nm) at concentrations from 0.1 to 200 µg/mL. NPs morphology, size, and charge were characterised by scanning electron microscopy, dynamic light scattering, and zeta potential. Cell morphology, viability, cell cycle distribution, and NPs internalisation were assessed by microscopy and flow cytometry. Low-concentration exposures had minimal effects, whereas 100 and 200 µg/mL induced marked morphological changes, including cytoplasmic granularity. Viability decreased significantly at 200 µg/mL for several NPs types, with PE NPs causing the largest reduction (79.4%). Polymer type influenced outcomes, with PE and PMMA NPs causing greater morphological disruption than PS. Size effects were most evident in cell cycle analysis: 15 nm and 20 nm PS NPs and 100 nm PMMA NPs induced phase arrest without major viability loss. NPs internalisation increased with concentration but varied with polymer type, with PE NPs showing preferential perinuclear localisation. These findings demonstrate that NPs effects on kidney cells depend on polymer chemistry, particle size, concentration, and highlight the need for long-term studies using environmentally relevant NPs to better assess kidney toxicity risk.

TsRNAs (tRNA-derived small RNAs) also known as tRNA-derived small RNAs, are a relatively new type of non-coding RNAs that have demonstrated promising effect in treating various liver diseases. However, the function of small extracellular vesicles (sEVs) secreted by human bone marrow mesenchymal stem cells (BMSCs) in safeguarding against metabolic-associated fatty liver disease (MAFLD) is still uncertain. In this research, we explored the effects of BMSCs sEVs on lipid metabolism using Palmitic Acid (PA)-induced HepG2 cells, both in the presence and absence of the sEVs inhibitor GW4869. Pandora sequencing and RNA sequencing were utilized to identify differentially expressed genes in sEVs and hepatocytes in vitro. Furthermore, we carried out in vivo studies involving male C57BL/6J mice that fed with high-fat diet (HFD) and either treated with an AAV 5'-tRF-GlyCCC mimic or not, through tail vein injection. Our findings revealed that BMSC-sEVs can relieve lipid accumulation in PA-caused HepG2 cells by inhibiting the formation of de novo fatty acid. We found that 5'-tRF-GlyCCC forms a direct connection with the 3' UTR of FoxO3, thereby decreasing the level of gluconeogenic genes PEPCK and G6Pase. Tail vein administration of the 5'-tRF-GlyCCC AAV alleviated liver gluconeogenesis and lipid metabolism issues in MAFLD mice by enhancing hepatic insulin sensitivity. The results imply that the 5'-tRF-GlyCCC/FoxO3 gluconeogenesis-signaling pathway could be crucial in the therapeutic benefits of BMSC sEVs on MAFLD.

Age-related decreases in follicle numbers and oocyte quality are major contributors to the decline in female fertility, which is associated with increased infertility rates. Emerging evidence suggests that targeting granulosa cell senescence could delay ovarian aging and depletion of the ovarian reserve, highlighting the potential for therapeutic interventions focused on granulosa cells. Advanced glycation end products (AGEs) accumulate with age and result in oxidative stress in the follicular microenvironment, but their direct impact on human granulosa cell (hGC) senescence and the fundamental processes are still mostly unknown. In this study, we found that AGEs treatment significantly exacerbated hGC senescence, impaired mitochondrial function, and suppressed mitophagy in a concentration-dependent manner. Importantly, these deficits were lessened by urolithin A-induced mitophagy activation, whereas Cyclosporine A-induced mitophagy inhibition had the reverse consequences. In addition, silencing Sirtuin 3 (SIRT3) or PINK1 further aggravated these adverse effects, while SIRT3 overexpression attenuated senescence and restored mitochondrial function by enhancing mitophagy. Furthermore, SIRT3 overexpression promoted the synthesis of estradiol-17β and progesterone, key hormones for ovarian function. Our findings demonstrated that AGEs induced hGC senescence by disrupting mitochondrial function and inhibiting mitophagy, with SIRT3 playing a protective role. Enhancing mitophagy by targeting SIRT3 may be a promising treatment approach to counteract age-related declines in female fertility.