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Oocyte meiotic maturation failure and chromosome abnormality is one of the main causes of infertility, abortion, and diseases. The mono-orientation of sister chromatids during the first meiosis is important for ensuring accurate chromosome segregation in oocytes. MEIKIN is a germ cell-specific protein that can regulate the mono-orientation of sister chromatids and the protection of the centromeric cohesin complex during meiosis I. Here we found that MEIKIN is a maternal protein that was highly expressed in mouse oocytes before the metaphase I (MI) stage, but became degraded by the MII stage and dramatically reduced after fertilization. Strikingly, MEIKIN underwent phosphorylation modification after germinal vesicle breakdown (GVBD), indicating its possible function in subsequent cellular event regulation. We further showed that MEIKIN phosphorylation was mediated by PLK1 at its carboxyl terminal region and its C-terminus was its key functional domain. To clarify the biological significance of meikin degradation during later stages of oocyte maturation, exogenous expression of MEIKIN was employed, which showed that suppression of MEIKIN degradation resulted in chromosome misalignment, cyclin B1 and Securin degradation failure, and MI arrest through a spindle assembly checkpoint (SAC)-independent mechanism. Exogenous expression of MEIKIN also inhibited metaphase II (MII) exit and early embryo development. These results indicate that proper MEIKIN expression level and its C-terminal phosphorylation by PLK1 are critical for regulating the metaphase-anaphase transition in meiotic oocyte. The findings of this study are important for understanding the regulation of chromosome segregation and the prevention meiotic abnormality.
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The kinetics of electrocatalytic reactions are closely related to the number and intrinsic activity of the active sites. Open active sites offer easy access to the substrate and allow for efficient desorption and diffusion of reaction products without significant hindrance. Metal-organic frameworks (MOFs) with open active sites show great potential in this context. To increase the density of active sites, trimesic acid was utilized as a ligand to anchor more Ni sites and in situ construct the nickel foam-loaded Ni-based trimesic MOF electrocatalyst (Ni-TMA-MOF/NF). When tested as an electrocatalyst for benzyl alcohol oxidation, Ni-TMA-MOF/NF exhibited lower overpotential and superior durability compared to Ni foam-loaded Ni-based terephthalic MOF electrocatalyst (Ni-PTA-MOF/NF) and Ni(OH)2 nanosheet array (Ni(OH)2/NF). Ni-TMA-MOF/NF required only a low potential of 1.65 V to achieve a high current density of 400 mA cm-2. Even after 40000 s of electrocatalytic oxidation at 1.5 V, Ni-TMA-MOF/NF maintained a current density of 175 mA cm-2 with â¼68% retention, showing its potential for benzyl alcohol oxidation. Through a combination of experimental and theoretical investigations, it was found that Ni-TMA-MOF/NF displayed superior electrocatalytic activity due to an optimized electron structure with high-valence Ni species and a high density of active sites, enabling long-term stable operation at high current densities. This study provides a new perspective on the design of electrocatalysts for benzyl alcohol oxidation.
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Pyroptosis is an inflammation-associated programmed cell death, and neuroinflammation is strongly associated with severe neurological deficits in neonatal hypoxic-ischemic encephalopathy (HIE). Ethyl pyruvate (EP), a known anti-inflammatory agent, has shown promise in the treatment of hypoxic-ischemic brain damage (HIBD) rats; nevertheless, the therapeutic mechanism of EP and its capacity to suppress neuronal pyroptosis in HIBD rats remain unclear. In both the neonatal Rice-Vannucci rat model and the OGD/R model, this study examined alterations in the NLRP3/Caspase-1/GSDMD classical pyroptosis pathway in hippocampal neurons during HIE and the potential inhibitory impact of ethyl pyruvate on this pathway. We used HE staining, immunofluorescence double staining, transmission electron microscopy, and western blot to demonstrate that EP effectively inhibited hippocampal neuronal pyroptosis and attenuated the activation of the NLRP3/Caspase-1/GSDMD signaling pathway in HIBD rats, which resulted in a reduction of neuroinflammation and facilitated neural recovery. The results suggest that EP may be a promising neuroprotective agent for treating HIE.
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OBJECTIVE: To explore the efficacy and safety of clonidine adhesive patch in Tourette syndrome (TS) patients with comorbid attentiondeficit/hyperactivity disorder (ADHD). METHODS: This study was conducted on a sample of children and adolescents with TS who had comorbid ADHD between May 2012 and March 2015. The patients were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders Fourth Edition, and were randomly assigned to four different dose groups: 1.0 mg/week, 1.5 mg/week, 2.0 mg/week and placebo group, and the symptom was evaluated by Swanson, Nolan, and Pelham Rating Scale, Version IV (SNAP-IV) and Yale Global Tic Severity Scale scales every 2 weeks. The primary outcome was tic disorders (TD) effective rate at week 8. RESULTS: One hundred and twenty-seven TS patients with comorbid ADHD in 2.0 mg/week (n=35), 1.5 mg/week (n=27), 1.0 mg/week (n=36) and placebo groups (n=29) were included in this subgroup analysis. The TD effective rate of the 2.0 mg, 1.5 mg, and 1.0 mg groups at week 8 were significantly better than that in placebo group (85.7%, 81.5%, and 86.1% vs. 20.7%, all p<0.0001). All groups demonstrated significant improvements in SNAP-IV total scale scores compared to baseline (p=0.0004), with treatment groups showing only a trend for better performance compared to placebo group at week 8, without statistical differences (22.1±15.41, 21.3±11.96, and 21.2±12.48 vs. 26.0±13.37, p=0.3385). A total of 9 adverse reactions occurred, all recovered spontaneously without additional medication. CONCLUSION: Clonidine adhesive patch could safely and effectively reduce the tic symptoms of TS patients with comorbid ADHD, and might be potentially helpful in the ADHD symptoms control.
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The timely degradation of proteins that regulate the cell cycle is essential for oocyte maturation. Oocytes are equipped to degrade proteins via the ubiquitin-proteasome system. In meiosis, anaphase promoting complex/cyclosome (APC/C), an E3 ubiquitin-ligase, is responsible for the degradation of proteins. Ubiquitin-conjugating enzyme E2 S (UBE2S), an E2 ubiquitin-conjugating enzyme, delivers ubiquitin to APC/C. APC/C has been extensively studied, but the functions of UBE2S in oocyte maturation and mouse fertility are not clear. In this study, we used Ube2s knockout mice to explore the role of UBE2S in mouse oocytes. Ube2s-deleted oocytes were characterized by meiosis I arrest with normal spindle assembly and spindle assembly checkpoint dynamics. However, the absence of UBE2S affected the activity of APC/C. Cyclin B1 and securin are two substrates of APC/C, and their levels were consistently high, resulting in the failure of homologous chromosome separation. Unexpectedly, the oocytes arrested in meiosis I could be fertilized and the embryos could become implanted normally, but died before embryonic day 10.5. In conclusion, our findings reveal an indispensable regulatory role of UBE2S in mouse oocyte meiosis and female fertility.
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Puntos de Control de la Fase M del Ciclo Celular , Meiosis , Animales , Femenino , Ratones , Ciclosoma-Complejo Promotor de la Anafase/genética , Ciclosoma-Complejo Promotor de la Anafase/metabolismo , Oocitos/metabolismo , Ubiquitinas/metabolismoRESUMEN
Myeloid-derived suppressor cells (MDSCs) play a crucial role in the immune escape mechanisms that limit the efficacy of immunotherapeutic strategies. In the tumor microenvironment, NLRP3 inflammasome-driven Interleukin-1ß (IL-1ß) production serves to dampen antitumor immune responses, promoting tumor growth, progression, and immunosuppression. In this study, we revealed that gold nanoparticles (Au NPs) with a size of 30 nm disrupted NLRP3 inflammasome, but not other inflammasomes, in bone marrow-derived macrophages through abrogating NLRP3-NEK7 interactions mediated by reactive oxygen species (ROS). Density functional theory (DFT) calculations provided insights into the mechanism underlying the exceptional ROS scavenging capabilities of Au NPs. Additionally, when coupled with H6, a small peptide targeting MDSCs, Au NPs demonstrated the capacity to effectively reduce IL-1ß levels and diminish the MDSCs population in tumor microenvironment, leading to enhanced T cell activation and increased immunotherapeutic efficacy in mouse tumor models that are sensitive and resistant to PD-1 inhibition. Our findings unraveled a novel approach wherein peptide-modified Au NPs relieved the suppressive impact of the tumor microenvironment by inhibiting MDSCs-mediated IL-1ß release, which is the first time reported the employing a nanostrategy at modulating MDSCs to reverse the immunosuppressive microenvironment and may hold promise as a potential therapeutic agent for cancer immunotherapy.
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Nanopartículas del Metal , Células Supresoras de Origen Mieloide , Neoplasias , Ratones , Animales , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Oro , Receptor de Muerte Celular Programada 1 , Especies Reactivas de Oxígeno , Inmunoterapia , Microambiente TumoralRESUMEN
Acute lung injury (ALI) is a severe and potentially fatal respiratory condition with limited treatment options. The pathological evolution of ALI is driven by persistent inflammation, destruction of the pulmonary vascular barrier and oxidative stress. Evidence from prior investigations has identified 5α-androst-3ß,5α,6ß-Triol (TRIOL), a synthetic analogue of the naturally occurring neuroprotective compound cholestane-3ß,5α,6ß-triol, possesses notable anti-inflammatory and antioxidative properties. However, the precise effects of TRIOL on alleviating lung injury along with the mechanisms, have remained largely unexplored. Here, TRIOL exhibited pronounced inhibitory actions on lipopolysaccharide (LPS)-induced inflammation and oxidative stress damage in both lung epithelial and endothelial cells. This protective effect is achieved by its ability to mitigate oxidative stress and restrain the inflammatory cascade orchestrated by nuclear factor-kappa B (NF-κB), thereby preserving the integrity of the pulmonary epithelial barrier. We further validated that TRIOL can attenuate LPS-induced lung injury in rats and mice by reducing inflammatory cell infiltration and improving pulmonary edema. Furthermore, TRIOL decreased the pro-inflammatory factors and increased of anti-inflammatory factors induced by LPS. In conclusion, our study presents TRIOL as a promising novel candidate for the treatment of ALI.
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Lesión Pulmonar Aguda , Células Endoteliales , Ratas , Ratones , Animales , Lipopolisacáridos/farmacología , Esteroides/farmacología , Estrés Oxidativo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Antiinflamatorios/farmacologíaRESUMEN
Triple-negative breast cancer (TNBC) is highly aggressive and metastatic, and has the poorest prognosis among all breast cancer subtypes. Activated ß-catenin is enriched in TNBC and involved in Wnt signaling-independent metastasis. However, the underlying mechanisms of ß-catenin activation in TNBC remain unknown. Here, we found that SHC4 was upregulated in TNBC and high SHC4 expression was significantly correlated with poor outcomes. Overexpression of SHC4 promoted TNBC aggressiveness in vitro and facilitated TNBC metastasis in vivo. Mechanistically, SHC4 interacted with Src and maintained its autophosphorylated activation, which activated ß-catenin independent of Wnt signaling, and finally upregulated the transcription and expression of its downstream genes CD44 and MMP7. Furthermore, we determined that the PxPPxPxxxPxxP sequence on CH2 domain of SHC4 was critical for SHC4-Src binding and Src kinase activation. Overall, our results revealed the mechanism of ß-catenin activation independent of Wnt signaling in TNBC, which was driven by SHC4-induced Src autophosphorylation, suggesting that SHC4 might be a potential prognostic marker and therapeutic target in TNBC.
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Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/patología , Familia-src Quinasas/genética , Familia-src Quinasas/metabolismo , Línea Celular Tumoral , beta Catenina/genética , beta Catenina/metabolismo , Proliferación Celular , Vía de Señalización Wnt/genética , Proteínas Adaptadoras de la Señalización Shc/genética , Proteínas Adaptadoras de la Señalización Shc/metabolismoRESUMEN
BACKGROUND: Studies have shown that deep-learning radiomics (DLR) could help differentiate glioblastoma (GBM) from solitary brain metastasis (SBM), but whether integrating demographic-MRI and DLR features can more accurately distinguish GBM from SBM remains uncertain. PURPOSE: To construct and validate a demographic-MRI deep-learning radiomics nomogram (DDLRN) integrating demographic-MRI and DLR signatures to differentiate GBM from SBM preoperatively. STUDY TYPE: Retrospective. POPULATION: Two hundred and thirty-five patients with GBM (N = 115) or SBM (N = 120), randomly divided into a training cohort (90 GBM and 98 SBM) and a validation cohort (25 GBM and 22 SBM). FIELD STRENGTH/SEQUENCE: Axial T2-weighted fast spin-echo sequence (T2WI), T2-weighted fluid-attenuated inversion recovery sequence (T2-FLAIR), and contrast-enhanced T1-weighted spin-echo sequence (CE-T1WI) using 1.5-T and 3.0-T scanners. ASSESSMENT: The demographic-MRI signature was constructed with seven imaging features ("pool sign," "irregular ring sign," "regular ring sign," "intratumoral vessel sign," the ratio of the area of peritumoral edema to the enhanced tumor, the ratio of the lesion area on T2-FLAIR to CE-T1WI, and the tumor location) and demographic factors (age and sex). Based on multiparametric MRI, radiomics and deep-learning (DL) models, DLR signature, and DDLRN were developed and validated. STATISTICAL TESTS: The Mann-Whitney U test, Pearson test, least absolute shrinkage and selection operator, and support vector machine algorithm were applied for feature selection and construction of radiomics and DL models. RESULTS: DDLRN showed the best performance in differentiating GBM from SBM with area under the curves (AUCs) of 0.999 and 0.947 in the training and validation cohorts, respectively. Additionally, the DLR signature (AUC = 0.938) outperformed the radiomics and DL models, and the demographic-MRI signature (AUC = 0.775) was comparable to the T2-FLAIR radiomics and DL models in the validation cohort (AUC = 0.762 and 0.749, respectively). DATA CONCLUSION: DDLRN integrating demographic-MRI and DLR signatures showed excellent performance in differentiating GBM from SBM. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.
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Metastasis remains the major cause of treatment failure in patients with nasopharyngeal carcinoma (NPC), in which sustained activation of the Notch signaling plays a critical role. N6-Methyladenosine (m6A)-mediated post-transcriptional regulation is involved in fine-tuning the Notch signaling output; however, the post-transcriptional mechanisms underlying NPC metastasis remain poorly understood. In the present study, we report that insulin-like growth factor 2 mRNA-binding proteins 3 (IGF2BP3) serves as a key m6A reader in NPC. IGF2BP3 expression was significantly upregulated in metastatic NPC and correlated with poor prognosis in patients with NPC. IGF2BP3 overexpression promoted, while IGF2BP3 downregulation inhibited tumor metastasis and the stemness phenotype of NPC cells in vitro and in vivo. Mechanistically, IGF2BP3 maintains NOTCH3 mRNA stability via suppression of CCR4-NOT complex-mediated deadenylation in an m6A-dependent manner, which sustains Notch3 signaling activation and increases the transcription of stemness-associated downstream genes, eventually promoting tumor metastasis. Our findings highlight the pro-metastatic function of the IGF2BP3/Notch3 axis and revealed the precise role of IGF2BP3 in post-transcriptional regulation of NOTCH3, suggesting IGF2BP3 as a novel prognostic biomarker and potential therapeutic target in NPC metastasis.
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Carcinoma , Neoplasias Nasofaríngeas , Humanos , Carcinoma/genética , Línea Celular Tumoral , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Receptor Notch3/genética , Transducción de Señal/genéticaRESUMEN
INTRODUCTION: Neonatal hypoxic-ischemic brain damage (HIBD) is a serious inflammatory injury. At present, the standard treatment for this disease is hypothermia therapy, and the effect of drug intervention is still limited. L-F001 is a compound of fasudil and lipoic acid. Previous in vitro experiments have confirmed that L-F001 has anti-inflammatory neuroprotective functions. However, its therapeutic effect on neonates with HIBD remains unknown. This study was aimed at exploring the therapeutic effect of L-F001 on HIBD rats. METHODS: The newborn rats were divided into three groups: Sham operation group, HIBD group, and HIBD + L-F001 group. HE staining, Nissil staining, the immunofluorescence of iNOS and COX-2, ELISA (IL-1ß, IL-6, TNF-α, and IL-10), and western blotting analyses were performed to determine the therapeutic effect of L-F001. Finally, we evaluated the growth and development of each group by measuring body weight. RESULTS: The hippocampal structure of HIBD rats was disordered, and the Nissil body was small and shallow. The expressions of iNOS and COX-2 in HIBD rats were increased, whereas the expressions of IL-1ß, IL-6, and TNF-α in plasma were upregulated, and the expression of IL-10 was decreased. L-F001 could improve the tissue structure and reduce the expression of iNOS and COX-2 in HIBD rats. Meanwhile, L-F001 could also reduce the expression of pro-inflammatory cytokines and restore the content of anti-inflammatory cytokines in plasma. We further found that the TLR4 pathway was activated after hypoxic-ischemia in neonatal rats. L-F001 could inhibit the activation of TLR4 pathway. Finally, we found that after L-F001 treatment, the body weight of HIBD rats increased significantly compared with the untreated group. CONCLUSIONS: L-F001 antagonizes the inflammatory response after hypoxic-ischemia by inhibiting the activation of the TLR4 signaling pathway, thus playing a neuroprotective role. L-F001 may be a potential therapeutic agent for neonatal HIBD.
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Hipoxia-Isquemia Encefálica , Ácido Tióctico , Ratas , Animales , Animales Recién Nacidos , Ratas Sprague-Dawley , Interleucina-10/metabolismo , Receptor Toll-Like 4/metabolismo , Factor 88 de Diferenciación Mieloide , Ácido Tióctico/farmacología , Ácido Tióctico/metabolismo , Interleucina-6 , Factor de Necrosis Tumoral alfa/metabolismo , Ciclooxigenasa 2/metabolismo , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Transducción de Señal , Isquemia , Hipocampo/metabolismo , Citocinas/metabolismo , Antiinflamatorios/farmacología , Peso CorporalRESUMEN
Cyst(e)ine is a key precursor for the synthesis of glutathione (GSH), which protects cancer cells from oxidative stress. Cyst(e)ine is stored in lysosomes, but its role in redox regulation is unclear. Here, we show that breast cancer cells upregulate major facilitator superfamily domain containing 12 (MFSD12) to increase lysosomal cyst(e)ine storage, which is released by cystinosin (CTNS) to maintain GSH levels and buffer oxidative stress. We find that mTORC1 regulates MFSD12 by directly phosphorylating residue T254, while mTORC1 inhibition enhances lysosome acidification that activates CTNS. This switch modulates lysosomal cyst(e)ine levels in response to oxidative stress, fine-tuning redox homeostasis to enhance cell fitness. MFSD12-T254A mutant inhibits MFSD12 function and suppresses tumor progression. Moreover, MFSD12 overexpression correlates with poor neoadjuvant chemotherapy response and prognosis in breast cancer patients. Our findings reveal the critical role of lysosomal cyst(e)ine storage in adaptive redox homeostasis and suggest that MFSD12 is a potential therapeutic target.
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The zona pellucida (ZP) is an extracellular glycoprotein matrix surrounding mammalian oocytes. Recently, numerous mutations in genes encoding ZP proteins have been shown to be possibly related to oocyte abnormality and female infertility; few reports have confirmed the functions of these mutations in living animal models. Here, we identified a novel heterozygous missense mutation (NM_001376231.1:c.1616C>T, p.Thr539Met) in ZP2 from a primary infertile female. We showed that the mutation reduced ZP2 expression and impeded ZP2 secretion in cell lines. Furthermore, we constructed the mouse model with the mutation (Zp2T541M) using CRISPR-Cas9. Zp2WT/T541M female mice had normal fertility though generated oocytes with the thin ZP, whereas Zp2T541M female mice were completely infertile due to degeneration of oocytes without ZP. Additionally, ZP deletion impaired folliculogenesis and caused female infertility in Zp2T541M mice. Our study not only expands the spectrum of ZP2 mutation sites but also, more importantly, increases the understanding of pathogenic mechanisms of ZP2 mutations.
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Sediment load in rivers is recognized as both a carrier and a potential source of contaminants. Sediment deposition significantly changes river flow and morphology, thereby affecting stream hydrology and aquatic life. We projected sediment load from the Pearl River basin (PRB), Mississippi into the northern Gulf of Mexico under a future climate with afforestation using the SWAT (Soil and Water Assessment Tool)-based HAWQS (Hydrologic and Water Quality System) model. Three simulation scenarios were developed in this study: (1) the past scenario for estimating the 40-year sediment load from 1981 to 2020; (2) the future scenario for projecting the 40-year sediment load from 2025 to 2064, and (3) the future afforestation scenario that was the same as the future scenario, except for converting the rangeland located in the middle section of the Pearl River watershed of the PRB into the mixed forest land cover. Simulations showed a 16% decrease in sediment load for the future scenario in comparison to the past scenario due to the decrease in future surface runoff. Over both the past and future 40 years, the monthly maximum and minimum sediment loads occurred, respectively, in April and August; whereas the seasonal sediment load followed the order: spring > winter > summer > fall. Among the four seasons, winter and spring accounted for about 86% of sediment load for both scenarios. Under the future 40-year climate conditions, a 10% reduction in annual average sediment load with afforestation was observed in comparison to without afforestation. This study provides new insights into how a future climate with afforestation would affect sediment load into the northern Gulf of Mexico.
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Metastasis in cervical cancer (CC) has a significant negative impact on patient survival, highlighting the urgent need for investigation in this area. In this study, we identified significant overexpression of zinc finger, X-linked, duplicated family member C (ZXDC) in CC tissue with metastasis, which correlates with poor outcomes for CC patients. We observed that overexpression of ZXDC promotes, while silencing of ZXDC inhibits the metastasis of CC cells both in vitro and in vivo. Additionally, our research demonstrated that ZXDC activated RhoA/ROCK signaling pathway, leading to enhanced cytoskeleton remodeling in CC cells. Besides, we found that IGF2BP3 plays an essential role in the activation of ZXDC on the RhoA/ROCK signaling pathway by stabilizing RhoA mRNA. These findings reveal a mechanism whereby ZXDC promotes the cervical cancer metastasis by targeting IGF2BP3/RhoA/ROCK pathway.
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Human epidermal growth factor receptor 2-targeted (HER2-targeted) therapy is the mainstay of treatment for HER2+ breast cancer. However, the proteolytic cleavage of HER2, or HER2 shedding, induces the release of the target epitope at the ectodomain (ECD) and the generation of a constitutively active intracellular fragment (p95HER2), impeding the effectiveness of anti-HER2 therapy. Therefore, identifying key regulators in HER2 shedding might provide promising targetable vulnerabilities against resistance. In the current study, we found that upregulation of dolichyl-phosphate N-acetylglucosaminyltransferase (DPAGT1) sustained high-level HER2 shedding to confer trastuzumab resistance, which was associated with poor clinical outcomes. Upon trastuzumab treatment, the membrane-bound DPAGT1 protein was endocytosed via the caveolae pathway and retrogradely transported to the ER, where DPAGT1 induced N-glycosylation of the sheddase - ADAM metallopeptidase domain 10 (ADAM10) - to ensure its expression, maturation, and activation. N-glycosylation of ADAM10 at N267 protected itself from ER-associated protein degradation and was essential for DPAGT1-mediated HER2 shedding and trastuzumab resistance. Importantly, inhibition of DPAGT1 with tunicamycin acted synergistically with trastuzumab treatment to block HER2 signaling and reverse resistance. These findings reveal a prominent mechanism for HER2 shedding and suggest that targeting DPAGT1 might be a promising strategy against trastuzumab-resistant breast cancer.
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Antineoplásicos , Neoplasias de la Mama , Humanos , Femenino , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transducción de Señal , Proteínas de la Membrana/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Antineoplásicos/farmacologíaRESUMEN
Accurate chromosome segregation, monitored by the spindle assembly checkpoint (SAC), is crucial for the production of euploid cells. Previous in vitro studies by us and others showed that Mad2, a core member of the SAC, performs a checkpoint function in oocyte meiosis. Here, through an oocyte-specific knockout approach in mouse, we reconfirmed that Mad2-deficient oocytes exhibit an accelerated metaphase-to-anaphase transition caused by premature degradation of securin and cyclin B1 and subsequent activation of separase in meiosis I. However, it was surprising that the knockout mice were completely fertile and the resulting oocytes were euploid. In the absence of Mad2, other SAC proteins, including BubR1, Bub3 and Mad1, were normally recruited to the kinetochores, which likely explains the balanced chromosome separation. Further studies showed that the chromosome separation in Mad2-null oocytes was particularly sensitive to environmental changes and, when matured in vitro, showed chromosome misalignment, lagging chromosomes, and aneuploidy with premature separation of sister chromatids, which was exacerbated at a lower temperature. We reveal for the first time that Mad2 is dispensable for proper chromosome segregation but acts to mitigate environmental stress in meiotic oocytes.
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Proteínas de Ciclo Celular , Huso Acromático , Animales , Ratones , Proteínas de Ciclo Celular/metabolismo , Huso Acromático/metabolismo , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Segregación Cromosómica/genética , Oocitos/metabolismo , Cinetocoros/metabolismo , Meiosis/genéticaRESUMEN
Sperm-induced Ca2+ rise is critical for driving oocyte activation and subsequent embryonic development, but little is known about how lasting Ca2+ oscillations are regulated. Here it is shown that NLRP14, a maternal effect factor, is essential for keeping Ca2+ oscillations and early embryonic development. Few embryos lacking maternal NLRP14 can develop beyond the 2-cell stage. The impaired developmental potential of Nlrp14-deficient oocytes is mainly caused by disrupted cytoplasmic function and calcium homeostasis due to altered mitochondrial distribution, morphology, and activity since the calcium oscillations and development of Nlrp14-deficient oocytes can be rescued by substitution of whole cytoplasm by spindle transfer. Proteomics analysis reveal that cytoplasmic UHRF1 (ubiquitin-like, containing PHD and RING finger domains 1) is significantly decreased in Nlrp14-deficient oocytes, and Uhrf1-deficient oocytes also show disrupted calcium homeostasis and developmental arrest. Strikingly, it is found that the mitochondrial Na+ /Ca2+ exchanger (NCLX) encoded by Slc8b1 is significantly decreased in the Nlrp14mNull oocyte. Mechanistically, NLRP14 interacts with the NCLX intrinsically disordered regions (IDRs) domain and maintain its stability by regulating the K27-linked ubiquitination. Thus, the study reveals NLRP14 as a crucial player in calcium homeostasis that is important for early embryonic development.
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Calcio , Nucleósido-Trifosfatasa , Semen , Humanos , Masculino , Calcio/metabolismo , Homeostasis/fisiología , Oocitos/metabolismo , Semen/metabolismo , Intercambiador de Sodio-Calcio/genética , Intercambiador de Sodio-Calcio/metabolismo , Ubiquitinación , Animales , Ratones , Nucleósido-Trifosfatasa/metabolismoRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: As prevalent acute respiratory condition in clinical practice, acute lung injury has a quick start and severe symptoms which can harm patients physically. Chaihu Qingwen granules (CHQW) is a classic formula for the treatment of respiratory diseases. Clinical observation shows that CHQW has good efficacy in treating colds, coughs, and fevers. AIM OF THE STUDY: The aim of this study was to investigate the anti-inflammatory effect of CHQW on lipopolysaccharide (LPS)-induced acute lung injury (ALI) model in rats and to explore its potential mechanism, as well as to clarify its substance composition. MATERIALS AND METHODS: Male SD rats were randomly divided into the blank group, the model group, the ibuprofen group, the Lianhua Qingwen capsule group and the CHQW group (2, 4 and 8 g/kg, respectively). The LPS-induced acute lung injury (ALI) model in rats was established after pre-administration. The histopathological changes in the lung and the levels of inflammatory factors in bronchoalveolar lavage fluid (BALF) and serum of ALI rats were observed. The inflammation-related proteins toll-like receptor 4 (TLR4), inhibitory kappa B alpha (IκBα), phospho-IκBα (p-IκBα), nuclear-factor-kappa B (NF-κB), and NLR family pyrin domain containing 3(NLRP3) expression levels were measured by western blotting analysis and immunohistochemical analysis. The chemical composition of CHQW was identified by liquid chromatography-quadrupole-time of flight-mass spectrometry (LC-Q-TOF-MS). RESULTS: CHQW significantly ameliorated lung tissue pathological injury in LPS-induced ALI rats and decreased the release of inflammatory cytokines (interleukin-1ß, interleukin-17 and tumor necrosis factor-α) in BALF and serum. In addition, CHQW decreased the expression of TLR4, p-IκBα and NF-κB proteins, increased the level of IκBα, regulated the TLR4/NF-κB signaling pathway, and inhibited the activation of NLRP3. The chemical components of CHQW were analyzed by LC-Q-TOF-MS, and a total of 48 components were identified by combining information from the literature, mainly flavonoids, organic acids, lignans, iridoids and phenylethanoid glycosides. CONCLUSION: The results of this study showed that the pretreatment of CHQW had a strong protective effect on LPS-induced ALI in rats, reducing lung tissue lesions and decreasing inflammatory cytokines released in BALF and serum. The protective mechanism of CHQW may be related to the inhibition of the TLR4/NF-κB signaling pathway and NLRP3 activation. The main active ingredients of CHQW are flavonoids, organic acids, lignans, iridoids and phenylethanoid glycosides.
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Lesión Pulmonar Aguda , FN-kappa B , Ratas , Masculino , Animales , FN-kappa B/metabolismo , Receptor Toll-Like 4/metabolismo , Inhibidor NF-kappaB alfa , Proteína con Dominio Pirina 3 de la Familia NLR , Lipopolisacáridos/farmacología , Ratas Sprague-Dawley , Pulmón , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Citocinas/metabolismo , Flavonoides/farmacología , Flavonoides/uso terapéutico , Antiinflamatorios/efectos adversos , Glicósidos/farmacologíaRESUMEN
Alternative splicing (AS) is a critical mechanism for the aberrant biogenesis of long non-coding RNA (lncRNA). Although the role of Wnt signaling in AS has been implicated, it remains unclear how it mediates lncRNA splicing during cancer progression. Herein, we identify that Wnt3a induces a splicing switch of lncRNA-DGCR5 to generate a short variant (DGCR5-S) that correlates with poor prognosis in esophageal squamous cell carcinoma (ESCC). Upon Wnt3a stimulation, active nuclear ß-catenin acts as a co-factor of FUS to facilitate the spliceosome assembly and the generation of DGCR5-S. DGCR5-S inhibits TTP's anti-inflammatory activity by protecting it from PP2A-mediated dephosphorylation, thus fostering tumor-promoting inflammation. Importantly, synthetic splice-switching oligonucleotides (SSOs) disrupt the splicing switch of DGCR5 and potently suppress ESCC tumor growth. These findings uncover the mechanism for Wnt signaling in lncRNA splicing and suggest that the DGCR5 splicing switch may be a targetable vulnerability in ESCC.