ABSTRACT
Senescence is a key barrier to neoplastic transformation. To identify senescence regulators relevant to cancer, we screened a genome-wide shRNA library. Here, we describe exportin 7 (XPO7) as a novel regulator of senescence and validate its function in telomere-induced, replicative, and oncogene-induced senescence (OIS). XPO7 is a bidirectional transporter that regulates the nuclear-cytoplasmic shuttling of a broad range of substrates. Depletion of XPO7 results in reduced levels of TCF3 and an impaired induction of the cyclin-dependent kinase inhibitor p21CIP1 during OIS. Deletion of XPO7 correlates with poorer overall survival in several cancer types. Moreover, depletion of XPO7 alleviated OIS and increased tumor formation in a mouse model of liver cancer. Our results suggest that XPO7 is a novel tumor suppressor that regulates p21CIP1 expression to control senescence and tumorigenesis.
Subject(s)
Cellular Senescence/genetics , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Karyopherins/genetics , Karyopherins/metabolism , ran GTP-Binding Protein/genetics , ran GTP-Binding Protein/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/metabolism , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p21/genetics , Female , Gene Expression Regulation, Developmental/genetics , Gene Knockdown Techniques , Humans , Mice , Neoplasms/physiopathology , Telomeric Repeat Binding Protein 2/geneticsABSTRACT
The cardiac sarcomere is a cellular structure in the heart that enables muscle cells to contract. Dozens of proteins belong to the cardiac sarcomere, which work in tandem to generate force and adapt to demands on cardiac output. Intriguingly, the majority of these proteins have significant intrinsic disorder that contributes to their functions, yet the biophysics of these intrinsically disordered regions (IDRs) have been characterized in limited detail. In this review, we first enumerate these myofilament-associated proteins with intrinsic disorder (MAPIDs) and recent biophysical studies to characterize their IDRs. We secondly summarize the biophysics governing IDR properties and the state-of-the-art in computational tools toward MAPID identification and characterization of their conformation ensembles. We conclude with an overview of future computational approaches toward broadening the understanding of intrinsic disorder in the cardiac sarcomere.
Subject(s)
Actin Cytoskeleton , Myofibrils , Myofibrils/metabolism , Sarcomeres/metabolism , Computer Simulation , Molecular ConformationABSTRACT
The regenerative ability of limb bones after injury decreases during aging, but whether a similar phenomenon occurs in jawbones and whether autophagy plays a role in this process remain unclear. Through retrospective analysis of clinical data and studies on a mouse model of jawbone defects, we confirmed the presence of delayed or impaired bone regeneration in the jawbones of old individuals and mice. Subsequently, osteoblasts (OBs) derived from mouse jawbones were isolated, showing reduced osteogenesis in senescent osteoblasts (S-OBs). We observed a reduction in autophagy within both aged jawbones and S-OBs. Additionally, pharmacological inhibition of autophagy in normal OBs (N-OBs) led to cell aging and decreased osteogenesis, while autophagic activation reversed the aging phenotype of S-OBs. The activator rapamycin (RAPA) increased the autophagy level and bone regeneration in aged jawbones. Finally, we found that fatty acid-binding protein 3 (FABP3) was degraded by autolysosomes through its interaction with sequestosome 1 (P62/SQSTM1). Autophagy inhibition within senescent jawbones and S-OBs led to the excessive accumulation of FABP3, and FABP3 knockdown partially rescued the decreased osteogenesis in S-OBs and alleviated age-related compromised jawbone regeneration. In summary, we confirmed that autophagy inhibition plays an important role in delaying bone regeneration in aging jawbones. Autophagic activation or FABP3 knockdown can partially rescue the osteogenesis of S-OBs and the regeneration of aging jawbones, providing insight into jawbone aging.
Subject(s)
Aging , Autophagy , Bone Regeneration , Fatty Acid-Binding Proteins , Osteoblasts , Osteogenesis , Animals , Female , Humans , Male , Mice , Aging/physiology , Aging/metabolism , Autophagy/physiology , Cellular Senescence/physiology , Fatty Acid-Binding Proteins/metabolism , Fatty Acid-Binding Proteins/genetics , Jaw , Mice, Inbred C57BL , Osteoblasts/metabolism , Osteogenesis/physiologyABSTRACT
ASPP2 and iASPP bind to p53 through their conserved ANK-SH3 domains to respectively promote and inhibit p53-dependent cell apoptosis. While crystallography has indicated that these two proteins employ distinct surfaces of their ANK-SH3 domains to bind to p53, solution NMR data has suggested similar surfaces. In this study, we employed multi-scale molecular dynamics (MD) simulations combined with free energy calculations to reconcile the discrepancy in the binding modes. We demonstrated that the binding mode based solely on a single crystal structure does not enable iASPP's RT loop to engage with p53's C-terminal linker-a verified interaction. Instead, an ensemble of simulated iASPP-p53 complexes facilitates this interaction. We showed that the ensemble-average inter-protein contacting residues and NMR-detected interfacial residues qualitatively overlap on ASPP proteins, and the ensemble-average binding free energies better match experimental KD values compared to single crystallgarphy-determined binding mode. For iASPP, the sampled ensemble complexes can be grouped into two classes, resembling the binding modes determined by crystallography and solution NMR. We thus propose that crystal packing shifts the equilibrium of binding modes towards the crystallography-determined one. Lastly, we showed that the ensemble binding complexes are sensitive to p53's intrinsically disordered regions (IDRs), attesting to experimental observations that these IDRs contribute to biological functions. Our results provide a dynamic and ensemble perspective for scrutinizing these important cancer-related protein-protein interactions (PPIs).
Subject(s)
Apoptosis Regulatory Proteins , Tumor Suppressor Protein p53 , Apoptosis Regulatory Proteins/chemistry , Tumor Suppressor Protein p53/chemistry , Crystallography , Protein Binding , ApoptosisABSTRACT
The stability of solution-processed semiconductors remains an important area for improvement on their path to wider deployment. Inorganic caesium lead halide perovskites have a bandgap well suited to tandem solar cells1 but suffer from an undesired phase transition near room temperature2. Colloidal quantum dots (CQDs) are structurally robust materials prized for their size-tunable bandgap3; however, they also require further advances in stability because they are prone to aggregation and surface oxidization at high temperatures as a consequence of incomplete surface passivation4,5. Here we report 'lattice-anchored' hybrid materials that combine caesium lead halide perovskites with lead chalcogenide CQDs, in which lattice matching between the two materials contributes to a stability exceeding that of the constituents. We find that CQDs keep the perovskite in its desired cubic phase, suppressing the transition to the undesired lattice-mismatched phases. The stability of the CQD-anchored perovskite in air is enhanced by an order of magnitude compared with pristine perovskite, and the material remains stable for more than six months at ambient conditions (25 degrees Celsius and about 30 per cent humidity) and more than five hours at 200 degrees Celsius. The perovskite prevents oxidation of the CQD surfaces and reduces the agglomeration of the nanoparticles at 100 degrees Celsius by a factor of five compared with CQD controls. The matrix-protected CQDs show a photoluminescence quantum efficiency of 30 per cent for a CQD solid emitting at infrared wavelengths. The lattice-anchored CQD:perovskite solid exhibits a doubling in charge carrier mobility as a result of a reduced energy barrier for carrier hopping compared with the pure CQD solid. These benefits have potential uses in solution-processed optoelectronic devices.
ABSTRACT
Adenosine bases of RNA can be transiently modified by the deposition of a methyl-group to form N6-methyladenosine (m6A). This adenosine-methylation is an ancient process and the enzymes involved are evolutionary highly conserved. A genetic screen designed to identify suppressors of late flowering transgenic Arabidopsis plants overexpressing the miP1a microProtein yielded a new allele of the FIONA1 (FIO1) m6A-methyltransferase. To characterize the early flowering phenotype of fio1 mutant plants we employed an integrative approach of mRNA-seq, Nanopore direct RNA-sequencing and meRIP-seq to identify differentially expressed transcripts as well as differentially methylated RNAs. We provide evidence that FIO1 is the elusive methyltransferase responsible for the 3'-end methylation of the FLOWERING LOCUS C (FLC) transcript. Furthermore, our genetic and biochemical data suggest that 3'-methylation stabilizes FLC mRNAs and non-methylated FLC is a target for rapid degradation.
Subject(s)
Arabidopsis Proteins , Arabidopsis , 3' Untranslated Regions/genetics , Adenosine/genetics , Adenosine/metabolism , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , Flowers/genetics , Flowers/metabolism , Gene Expression Regulation, Plant , Histones/genetics , MADS Domain Proteins/genetics , MADS Domain Proteins/metabolism , Methylation , Methyltransferases/genetics , Plants, Genetically Modified/genetics , Plants, Genetically Modified/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolismABSTRACT
Chimeric antigen receptor (CAR) T-cell therapy is highly effective for treating blood cancers such as B-cell malignancies, however, its effectiveness as an approach to treat solid tumors remains to be further explored. Here, we focused on the development of CAR-T cell therapies targeting tropomyosin-related kinase receptor B (TRKB), a highly expressed protein that is significantly associated with tumor progression, malignancy, and drug resistance in multiple forms of aggressive solid tumors. To achieve this, we screened brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NTF4) ligand-based CAR-T cells for their efficiency in targeting the TRKB receptor in the context of solid tumors, particularly hepatocellular carcinoma and pancreatic cancer. We demonstrated that TRKB is overexpressed not only in hepatocellular carcinoma and pancreatic carcinoma cell lines but also in cancer stem-like cells (CSCs). Notably, BDNF-CAR T and NTF4-CAR T cells could not only effectively target and kill TRKB-expressing pan-cancer cell lines in a dose-dependent manner but also effectively kill CSCs. We also performed in vivo studies to show that NTF4-CAR T cells have a better potential to inhibit the tumor growth of hepatocellular carcinoma xenografts in mice, compared with BDNF-CAR T cells. Taken together, our findings suggest that CAR-T targeting TRKB may be a promising approach for developing novel therapies to treat solid cancers.
ABSTRACT
The identification of a specific tumor cell is crucial for the early diagnosis and treatment of cancer. However, it remains a challenge due to the limited sensitivity and accuracy, long response time, and low contrast of the recent approaches. In this study, we develop a dual miRNA-triggered DNA walker (DMTDW) assisted by APE1 for the specific recognition of tumor cells. miR-10b and miR-155 were selected as the research models. Without miR-10b and miR-155 presence, the DNA walker remains inactive as its walking strand of W is locked by L1 and L2. After miR-10b and miR-155 are input, the DNA walker is triggered as miR-10b and miR-155 bind to L1 and L2 of W-L1-L2, respectively, unlocking W. The DNA walker is driven by endogenous APE1 that is highly catalytic and is highly expressed in the cytoplasm of tumor cells but barely expressed in normal cells, ensuring high contrast and reaction efficiency for specific recognition of tumor cells. Dual miRNA input is required to trigger the DNA walker, making this strategy with a high accuracy. The DMTDW strategy exhibited high sensitivity for miRNA analysis with a detection limit of 44.05 pM. Living cell-imaging experiments confirmed that the DMTDW could effectively respond to the fluctuation of miRNA and specifically identified MDA-MB-231 cells from different cell lines. The proposed DMTDW is sensitive, rapid, and accurate for specific tumor cell recognition. We believe that the DMTDW strategy can become a powerful diagnostic tool for the specific recognition of tumor cells.
Subject(s)
DNA-(Apurinic or Apyrimidinic Site) Lyase , MicroRNAs , MicroRNAs/analysis , MicroRNAs/metabolism , MicroRNAs/genetics , Humans , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism , DNA/chemistry , Cell Line, TumorABSTRACT
Due to the complex pathogenesis of acute ischemic stroke (AIS), further investigation into its underlying mechanisms is necessary. Presently, existing literature indicates a close association between ferroptosis and AIS injury; however, the precise mechanism and molecular target of ferroptosis in AIS injury remain elusive. By RNA sequencing, we found a significant increase in LCN2 expression in the ischemic cortex. In order to investigate the potential role of LCN2 in modulating AIS injury through the regulation of ferroptosis, we utilized RNA interference (RNAi) knockdown and gene overexpression experiments. The findings from experiments conducted both in vitro and in vivo revealed a marked increase in ferroptosis levels within the AIS model group. Suppression of the LCN2 gene resulted in a significant reduction in ferroptosis levels in OGD/R cells. Conversely, upregulation of LCN2 exacerbated ferroptosis levels in OGD/R cells. The results suggest that elevated levels of ferroptosis may result from heightened expression of LCN2, thereby exacerbating ischemia/reperfusion injury. This study indicates the involvement of ferroptosis in the pathogenesis of AIS and highlights LCN2 as a regulator of ferroptosis in AIS-induced injury, suggesting a potential therapeutic target for ischemic stroke.
ABSTRACT
PIK3CA-related overgrowth spectrum (PROS) is an umbrella term to describe a diverse range of developmental disorders. Research to date has predominantly emerged from Europe and North America, resulting in a notable scarcity of studies focusing on East Asian populations. Currently, the prevalence and distribution of PIK3CA variants across various genetic loci and their correlation with distinct phenotypes in East Asian populations remain unclear. This study aims to elucidate the phenotype-genotype correlations of PROS in East Asian populations. We presented the phenotypes and genotypes of 82 Chinese patients. Among our cohort, 67 individuals carried PIK3CA variants, including missense, frameshift, and splice variants. Six patients presented with both PIK3CA and an additional variant. Seven PIK3CA-negative patients exhibited overlapping PROS manifestations with variants in GNAQ, AKT1, PTEN, MAP3K3, GNA11, or KRAS. An integrative review of the literature pertaining to East Asian populations revealed that specific variants are uniquely associated with certain PROS phenotypes. Some rare variants were exclusively identified in cases of megalencephaly and diffuse capillary malformation with overgrowth. Non-hotspot variants with undefined oncogenicity were more common in CNS phenotypes. Diseases with vascular malformation were more likely to have variants in the helical domain, whereas phenotypes involving adipose/muscle overgrowth without vascular abnormalities predominantly presented variants in the C2 domain. Our findings underscore the unique phenotype-genotype patterns within the East Asian PROS population, highlighting the necessity for an expanded cohort to further elucidate these correlations. Such endeavors would significantly facilitate the development of PI3Kα selective inhibitors tailored for the East Asian population in the future.
Subject(s)
Asian People , Class I Phosphatidylinositol 3-Kinases , Genotype , Phenotype , Humans , Class I Phosphatidylinositol 3-Kinases/genetics , Female , Male , Child , Child, Preschool , Asian People/genetics , Genetic Association Studies , Infant , Growth Disorders/genetics , Growth Disorders/pathology , Adolescent , Mutation , Asia, Eastern , East Asian PeopleABSTRACT
Tumor penetration of nanoparticles is crucial in nanomedicine, but the mechanisms of tumor penetration are poorly understood. This work presents a multidimensional, quantitative approach to investigate the tissue penetration behavior of nanoparticles, with focuses on the particle size effect on penetration pathways, in an MDA-MB-231 tumor spheroid model using a combination of spectrometry, microscopy, and synchrotron beamline techniques. Quasi-spherical gold nanoparticles of different sizes are synthesized and incubated with 2D and 3D MDA-MB-231 cells and spheroids with or without an energy-dependent cell uptake inhibitor. The distribution and penetration pathways of nanoparticles in spheroids are visualized and quantified by inductively coupled plasma mass spectrometry, two-photon microscopy, and synchrotron X-ray fluorescence microscopy. The results reveal that 15 nm nanoparticles penetrate spheroids mainly through an energy-independent transcellular pathway, while 60 nm nanoparticles penetrate primarily through an energy-dependent transcellular pathway. Meanwhile, 22 nm nanoparticles penetrate through both transcellular and paracellular pathways and they demonstrate the greatest penetration ability in comparison to other two sizes. The multidimensional analytical methodology developed through this work offers a generalizable approach to quantitatively study the tissue penetration of nanoparticles, and the results provide important insights into the designs of nanoparticles with high accumulation at a target site.
Subject(s)
Metal Nanoparticles , Nanoparticles , Neoplasms , Humans , Gold/chemistry , Spheroids, Cellular , Nanoparticles/chemistry , MicroscopyABSTRACT
Percutaneous coronary intervention is the main strategy of revascularization and has been shown to improve outcomes in some patients with ST-segment elevation myocardial infarction (STEMI). However, multivessel disease (MVD), a common condition in these patients, is associated with worse clinical outcomes compared to single-vessel disease. Despite intervention being a standard treatment for coronary artery disease, optimal strategies and timings for patients with STEMI and MVD remain unclear. Numerous studies and meta-analyses have investigated this topic; however, many current conclusions are based on observational studies. Furthermore, clinical guidelines regarding the management of patients with STEMI and MVD contain conflicting recommendations. Therefore, we aimed to compile relevant studies and newly available evidence-based medicines to explore the most effective approach.
ABSTRACT
BACKGROUND: Magnetic resonance imaging (MRI) reference ranges for ventricular morphology and function in the Chinese population are lacking. PURPOSE: To establish the MRI reference ranges of left and right ventricular (LV and RV) morphology and function based on a large multicenter cohort. STUDY TYPE: Prospective. POPULATION: One thousand and twelve healthy Chinese Han adults. FIELD STRENGTH/SEQUENCE: Balanced steady-state free procession cine sequence at 3.0 T. ASSESSMENT: Biventricular end-diastolic, end-systolic, stroke volume, and ejection fraction (EDV, ESV, SV, and EF), LV mass (LVM), end-diastolic and end-systolic dimension (LVEDD and LVESD), anteroseptal wall thickness (AS), and posterolateral wall thickness (PL) were measured. Body surface area (BSA) and height were used to index biventricular parameters. Parameters were compared between age groups and sex. STATISTICAL TESTS: Independent-samples t-tests or Mann-Whitney U test to compare mean values between sexes; ANOVA or Kruskal-Wallis test to compare mean values among age groups; linear regression to assess the relationships between cardiac parameters and age (correlation coefficient, r). A P value <0.05 was considered statistically significant. RESULTS: The biventricular volumes, LVM, LVEDD, RVEDV/LVEDV ratio, LVESD, AS, and PL were significantly greater in males than in females, even after indexing to BSA or height, while LVEF and RVEF were significantly lower in males than in females. For both sexes, age was significantly negatively correlated with biventricular volumes (male and female: LVEDV [r = -0.491; r = -0.373], LVESV [r = -0.194; r = -0.184], RVEDV [r = -0.639; r = -0.506], RVESV [r = -0.270; r = -0.223]), with similar correlations after BSA normalization. LVEF (r = 0.043) and RVEF (r = 0.033) showed a significant correlation with age in females, but not in males (P = 0.889; P = 0.282). DATA CONCLUSION: MRI reference ranges for biventricular morphology and function in Chinese adults are presented and show significant associations with age and sex. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.
Subject(s)
Heart Ventricles , Magnetic Resonance Imaging , Adult , Humans , Male , Female , Stroke Volume , Reference Values , Prospective Studies , Magnetic Resonance Imaging/methods , China , Ventricular Function, Left , Ventricular Function, RightABSTRACT
The metal-support interaction is crucial for the performance of Cu-based catalysts. However, the distinctive properties of the support metal element itself are often overlooked in catalyst design. In this paper, a sheet Cu-Zn-Ce with [Ce3+-OV-Ce4+] located on the surface was designed by the sol-gel method. Through EPR and X-ray photoelectron spectroscopy (XPS), the relationship between the content of oxygen vacancies and Ce was revealed. Ce itself induces the generation of [Ce3+-OV-Ce4+]. Through ICP-MS, XPS, and SEM-mapping, the Ce-induced formation of [Ce3+-OV-Ce4+] located on the catalyst surface was demonstrated. CO2-TPD and DFT calculations further revealed that [Ce3+-OV-Ce4+] enhanced CO2 adsorption, leading to a 10% increase in methanol selectivity compared to Cu-Zn-Ce synthesized via the coprecipitation method.
ABSTRACT
Maternal sleep is closely related to subsequent gestational diabetes mellitus (GDM) in natural pregnancies. However, whether this connection exists in pregnant women conceiving with the help of assisted reproductive technology (ART) has not been confirmed. Hence, in this study, we evaluated whether early pregnancy sleep duration or sleep quality is associated with gestational diabetes mellitus in ART-pregnant women, as well as the influence of maternal age on this association. This prospective birth cohort study included 856 pregnant women who successfully conceived with the help of ART treatment. The sleep parameters of ART-pregnant women were assessed using the Pittsburgh Sleep Quality Index (PSQI) in early pregnancy. We explored the association between sleep and the risk of gestational diabetes mellitus using an unconditional binary logistic regression model. Different models were constructed to examine the robustness of the estimation by incorporating different confounding factors. Multivariable logistic regression revealed that sleep duration of more than 10 h among ART-pregnant women was significantly associated with the risk of GDM, and the association between sleep duration and gestational diabetes mellitus varied by maternal age. We found an increased risk of subsequent gestational diabetes mellitus with increasing sleep duration only in pregnant women aged <35 years. Additionally, no statistically significant association between sleep quality and gestational diabetes mellitus was found in this study. In conclusion, excessive sleep duration (≥10 h) is associated with a high risk of gestational diabetes mellitus in pregnant women who conceived with the help of assisted reproductive technology, and maternal age may modify this effect.
ABSTRACT
BACKGROUND: Current therapies cannot completely reverse advanced atherosclerosis. High levels of amino acids, induced by Western diet, stimulate mTORC1 (mammalian target of rapamycin complex 1)-autophagy defects in macrophages, accelerating atherosclerotic plaque progression. In addition, autophagy-lysosomal dysfunction contributes to plaque necrotic core enlargement and lipid accumulation. Therefore, it is essential to investigate the novel mechanism and molecules to reverse amino acid-mTORC1-autophagy signaling dysfunction in macrophages of patients with advanced atherosclerosis. METHODS: We observed that Gpr137b-ps (G-protein-coupled receptor 137B, pseudogene) was upregulated in advanced atherosclerotic plaques. The effect of Gpr137b-ps on the progression of atherosclerosis was studied by generating advanced plaques in ApoE-/- mice with cardiac-specific knockout of Gpr137b-ps. Bone marrow-derived macrophages and mouse mononuclear macrophage cell line RAW264.7 cells were subjected to starvation or amino acid stimulation to study amino acid-mTORC1-autophagy signaling. Using both gain- and loss-of-function approaches, we explored the mechanism of Gpr137b-ps-regulated autophagy. RESULTS: Our results demonstrated that Gpr137b-ps deficiency led to enhanced autophagy in macrophages and reduced atherosclerotic lesions, characterized by fewer necrotic cores and less lipid accumulation. Knockdown of Gpr137b-ps increased autophagy and prevented amino acid-induced mTORC1 signaling activation. As the downstream binding protein of Gpr137b-ps, HSC70 (heat shock cognate 70) rescued the impaired autophagy induced by Gpr137b-ps. Furthermore, Gpr137b-ps interfered with the HSC70 binding to G3BP (Ras GTPase-activating protein-binding protein), which tethers the TSC (tuberous sclerosis complex) complex to lysosomes and suppresses mTORC1 signaling. In addition to verifying that the NTF2 (nuclear transport factor 2) domain of G3BP binds to HSC70 by in vitro protein synthesis, we further demonstrated that HSC70 binds to the NTF2 domain of G3BP through its W90-F92 motif by using computational modeling. CONCLUSIONS: These findings reveal that Gpr137b-ps plays an essential role in the regulation of macrophage autophagy, which is crucial for the progression of advanced atherosclerosis. Gpr137b-ps impairs the interaction of HSC70 with G3BP to regulate amino acid-mTORC1-autophagy signaling, and these results provide a new potential therapeutic direction for the treatment of advanced atherosclerosis.
Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , RNA, Long Noncoding , Humans , Mice , Animals , RNA, Long Noncoding/metabolism , Atherosclerosis/pathology , Plaque, Atherosclerotic/pathology , Macrophages/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Autophagy/physiology , Amino Acids/metabolism , Lipids , Mammals/geneticsABSTRACT
The purpose of this study was to identify the target genes of tcon_00044595, elucidate its activation site, and provide novel insights into the pathogenesis and treatment of neonatal hypoxic-ischemic brain damage (HIBD). Through homologous blast analysis, we identified predicted target sequences in the neighboring regions of the long non-coding RNA (lncRNA) tcon_00044595, suggesting that limd1 is its target gene. Starbase was utilized to identify potential candidate microRNAs associated with the lncRNA. The interaction between the candidate microRNAs and limd1 was investigated and validated using various experimental methods including in vitro cell culture, cell transfection, dual fluorescence reporter detection system, and real-time PCR. Homology alignment analysis revealed that the lncRNA tcon_00044595 exhibited a 246 bp homologous sequence at the 3' end of the adjacent limd1 gene, with a conservation rate of 68%. Analysis conducted on Starbase online identified three potential microRNA candidates: miR-3471, miR-883a-5p, and miR-214-3p. Intracellular expression of the limd1 gene was significantly down-regulated upon transfection with miR-3471, while the other two microRNAs did not produce noticeable effects. Luciferase reporter assays identified two interaction sites (UTR-1, UTR-2) between miR-3471 and the limd1 3'UTR, with UTR-1 exhibiting a strong influence. Further CCK8 assay indicated a protective role of miR-3471 during low oxygen stroke in HIBD. The potential regulatory relationship between lncRNA (tcon_00044595), miR-3471, and the target gene limd1 suggests their involvement in the occurrence and development of HIBD, providing new insights for investigating the underlying mechanisms and exploring targeted therapeutic approaches for HIBD.
Subject(s)
Hypoxia-Ischemia, Brain , MicroRNAs , RNA, Long Noncoding , Humans , Infant, Newborn , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , MicroRNAs/genetics , Hypoxia-Ischemia, Brain/genetics , Hypoxia-Ischemia, Brain/metabolism , Hypoxia-Ischemia, Brain/pathology , Apoptosis , OxygenABSTRACT
Despite the increasing health risks shown by the continuous detection of organophosphate esters (OPEs) in biota in recent years, information on the occurrence and potential risks of OPEs in marine mammals remains limited. This study conducted the first investigation into the body burdens and potential risks of 10 traditional OPEs (tOPEs) and five emerging OPEs (eOPEs) in 10 cetacean species (n = 84) from the northern South China Sea (NSCS) during 2005-2021. All OPEs, except for 2-ethylhexyl diphenyl phosphate (EHDPHP), were detected in these cetaceans, indicating their widespread occurrence in the NSCS. Although the levels of the ∑10tOPEs in humpback dolphins remained stable from 2005 to 2021, the concentrations of the ∑5eOPEs showed a significant increase, suggesting a growing demand for these new-generation OPEs in South China. Dolphins in proximity to urban regions generally exhibited higher OPE concentrations than those from rural areas, mirroring the environmental trends of OPEs occurring in this area. All OPE congeners, except for EHDPHP, in humpback dolphins exhibited a maternal transfer ratio >1, indicating that the dolphin placenta may not be an efficient barrier for OPEs. The observed significant correlations between levels of OPEs and hormones (triiodothyronine, thyroxine, and testosterone) in humpback dolphins indicated that OPE exposures might have endocrine disruption effects on the dolphin population.
Subject(s)
Dolphins , Flame Retardants , Animals , Environmental Monitoring , Bioaccumulation , Esters , China , Organophosphates , Phosphates , Flame Retardants/analysisABSTRACT
Four undescribed coumarin derivatives, ficusalt A (1) and ficusalt B (2), a pair of racemic coumarins, (±) ficudimer A (3a/3b), along with ten known amides, were isolated from the roots of Ficus hirta. Their structures were elucidated by several spectroscopic data analyses, including HRESIMS, NMR, and X-ray single-crystal diffraction. The cytotoxic activities of all compounds against HeLa, HepG2, MCF-7, and H460 cell lines were detected using the MTT assay. Among these, 5 showed the highest activity against HeLa cells. Subsequently, the apoptotic, anti-invasive, and anti-migration effects of 5 on HeLa cells were determined by flow cytometer, transwell invasion assay, and wound-healing assay, respectively. The result suggested that 5 distinctly induced the apoptosis in HeLa cells and inhibited their invasion and migration. Further studies on anticancer mechanisms were conducted using Western blotting. As a result, 5 increased the cleavage of PARP and the expression of pro-apoptotic protein Bax. Moreover, 5 notably upregulated the phosphorylation of p38 and JNK, whereas inhibited the expression of p-ERK and p-AKT. Our results demonstrated that 5 could be a potential leading compound for further application in the treatment of cervical cancer.
Subject(s)
Antineoplastic Agents , Ficus , Female , Humans , HeLa Cells , Ficus/chemistry , Amides/pharmacology , Coumarins/pharmacology , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , ApoptosisABSTRACT
Hypoxia-ischemia (HI) is one of the main causes of neonatal brain injury. Mitophagy has been implicated in the degradation of damaged mitochondria and cell survival following neonatal brain HI injury. Pleckstrin homology-like domain family A member 1 (PHLDA1) plays vital roles in the progression of various disorders including the regulation of oxidative stress, the immune responses and apoptosis. In the present study we investigated the role of PHLDA1 in HI-induced neuronal injury and further explored the mechanisms underlying PHLDA1-regulated mitophagy in vivo and in vitro. HI model was established in newborn rats by ligation of the left common carotid artery plus exposure to an oxygen-deficient chamber with 8% O2 and 92% N2. In vitro studies were conducted in primary hippocampal neurons subjected to oxygen and glucose deprivation/-reoxygenation (OGD/R). We showed that the expression of PHLDA1 was significantly upregulated in the hippocampus of HI newborn rats and in OGD/R-treated primary neurons. Knockdown of PHLDA1 in neonatal rats via lentiviral vector not only significantly ameliorated HI-induced hippocampal neuronal injury but also markedly improved long-term cognitive function outcomes, whereas overexpression of PHLDA1 in neonatal rats via lentiviral vector aggravated these outcomes. PHLDA1 knockdown in primary neurons significantly reversed the reduction of cell viability and increase in intracellular reactive oxygen species (ROS) levels, and attenuated OGD-induced mitochondrial dysfunction, whereas overexpression of PHLDA1 decreased these parameters. In OGD/R-treated primary hippocampal neurons, we revealed that PHLDA1 knockdown enhanced mitophagy by activating FUNDC1, which was abolished by FUNDC1 knockdown or pretreatment with mitophagy inhibitor Mdivi-1 (25 µM). Notably, pretreatment with Mdivi-1 or the knockdown of FUNDC1 not only increased brain infarct volume, but also abolished the neuroprotective effect of PHLDA1 knockdown in HI newborn rats. Together, these results demonstrate that PHLDA1 contributes to neonatal HI-induced brain injury via inhibition of FUNDC1-mediated neuronal mitophagy.