ABSTRACT
Liver fibrosis is a very common condition seen in millions of patients with various liver diseases, and yet no effective treatments are available owing to poorly characterized molecular pathogenesis. Here, we show that leukocyte cell-derived chemotaxin 2 (LECT2) is a functional ligand of Tie1, a poorly characterized endothelial cell (EC)-specific orphan receptor. Upon binding to Tie1, LECT2 interrupts Tie1/Tie2 heterodimerization, facilitates Tie2/Tie2 homodimerization, activates PPAR signaling, and inhibits the migration and tube formations of EC. In vivo studies showed that LECT2 overexpression inhibits portal angiogenesis, promotes sinusoid capillarization, and worsens fibrosis, whereas these changes were reversed in Lect2-KO mice. Adeno-associated viral vector serotype 9 (AAV9)-LECT2 small hairpin RNA (shRNA) treatment significantly attenuates fibrosis. Upregulation of LECT2 is associated with advanced human liver fibrosis staging. We concluded that targeting LECT2/Tie1 signaling may represent a potential therapeutic target for liver fibrosis, and serum LECT2 level may be a potential biomarker for the screening and diagnosis of liver fibrosis.
Subject(s)
Endothelial Cells/metabolism , Hepatocytes/metabolism , Intercellular Signaling Peptides and Proteins/physiology , Liver Cirrhosis/metabolism , Liver/metabolism , Receptors, TIE/metabolism , Animals , Biomarkers/metabolism , Capillaries/metabolism , Endothelial Cells/cytology , Endothelial Cells/pathology , HEK293 Cells , Hepatocytes/cytology , Hepatocytes/pathology , Humans , Intercellular Signaling Peptides and Proteins/blood , Liver/blood supply , Liver/pathology , Liver Cirrhosis/diagnosis , Mice, Inbred C57BLABSTRACT
How cell-to-cell copy number alterations that underpin genomic instability1 in human cancers drive genomic and phenotypic variation, and consequently the evolution of cancer2, remains understudied. Here, by applying scaled single-cell whole-genome sequencing3 to wild-type, TP53-deficient and TP53-deficient;BRCA1-deficient or TP53-deficient;BRCA2-deficient mammary epithelial cells (13,818 genomes), and to primary triple-negative breast cancer (TNBC) and high-grade serous ovarian cancer (HGSC) cells (22,057 genomes), we identify three distinct 'foreground' mutational patterns that are defined by cell-to-cell structural variation. Cell- and clone-specific high-level amplifications, parallel haplotype-specific copy number alterations and copy number segment length variation (serrate structural variations) had measurable phenotypic and evolutionary consequences. In TNBC and HGSC, clone-specific high-level amplifications in known oncogenes were highly prevalent in tumours bearing fold-back inversions, relative to tumours with homologous recombination deficiency, and were associated with increased clone-to-clone phenotypic variation. Parallel haplotype-specific alterations were also commonly observed, leading to phylogenetic evolutionary diversity and clone-specific mono-allelic expression. Serrate variants were increased in tumours with fold-back inversions and were highly correlated with increased genomic diversity of cellular populations. Together, our findings show that cell-to-cell structural variation contributes to the origins of phenotypic and evolutionary diversity in TNBC and HGSC, and provide insight into the genomic and mutational states of individual cancer cells.
Subject(s)
Genomics , Mutation , Ovarian Neoplasms , Single-Cell Analysis , Triple Negative Breast Neoplasms , Female , Humans , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Phylogeny , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/pathologyABSTRACT
We have previously proposed that selective inheritance, the limited transmission of damaging mtDNA mutations from mother to offspring, is based on replication competition in Drosophila melanogaster. This model, which stems from our observation that wild-type mitochondria propagate much more vigorously in the fly ovary than mitochondria carrying fitness-impairing mutations, implies that germ cells recognize the fitness of individual mitochondria and selectively boost the propagation of healthy ones. Here, we demonstrate that the protein kinase PINK1 preferentially accumulates on mitochondria enriched for a deleterious mtDNA mutation. PINK1 phosphorylates Larp to inhibit protein synthesis on the mitochondrial outer membrane. Impaired local translation on defective mitochondria in turn limits the replication of their mtDNA and hence the transmission of deleterious mutations to the offspring. Our work confirms that selective inheritance occurs at the organelle level during Drosophila oogenesis and provides molecular entry points to test this model in other systems.
Subject(s)
DNA Replication , DNA, Mitochondrial/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/enzymology , Mitochondria/enzymology , Mitochondrial Membranes/enzymology , Mitochondrial Proteins/biosynthesis , Mutation , Oocytes/enzymology , Protein Serine-Threonine Kinases/metabolism , Animals , Animals, Genetically Modified , DNA, Mitochondrial/biosynthesis , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Female , Inheritance Patterns , Mitochondria/genetics , Mitochondrial Proteins/genetics , Oogenesis , Organelle Biogenesis , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Protein Stability , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
BACKGROUND: Medial arterial calcification is a chronic systemic vascular disorder distinct from atherosclerosis and is commonly observed in patients with chronic kidney disease, diabetes, and aging individuals. We previously showed that NR4A3 (nuclear receptor subfamily 4 group A member 3), an orphan nuclear receptor, is a key regulator in apo (apolipoprotein) A-IV-induced atherosclerosis progression; however, its role in vascular calcification is poorly understood. METHODS: We generated NR4A3-/- mice and 2 different types of medial arterial calcification models to investigate the biological roles of NR4A3 in vascular calcification. RNA-seq was performed to determine the transcriptional profile of NR4A3-/- vascular smooth muscle cells under ß-glycerophosphate treatment. We integrated Cleavage Under Targets and Tagmentation analysis and RNA-seq data to further investigate the gene regulatory mechanisms of NR4A3 in arterial calcification and target genes regulated by histone lactylation. RESULTS: NR4A3 expression was upregulated in calcified aortic tissues from chronic kidney disease mice, 1,25(OH)2VitD3 overload-induced mice, and human calcified aorta. NR4A3 deficiency preserved the vascular smooth muscle cell contractile phenotype, inhibited osteoblast differentiation-related gene expression, and reduced calcium deposition in the vasculature. Further, NR4A3 deficiency lowered the glycolytic rate and lactate production during the calcification process and decreased histone lactylation. Mechanistic studies further showed that NR4A3 enhanced glycolysis activity by directly binding to the promoter regions of the 2 glycolysis genes ALDOA and PFKL and driving their transcriptional initiation. Furthermore, histone lactylation promoted medial calcification both in vivo and in vitro. NR4A3 deficiency inhibited the transcription activation and expression of Phospho1 (phosphatase orphan 1). Consistently, pharmacological inhibition of Phospho1 attenuated calcium deposition in NR4A3-overexpressed vascular smooth muscle cells, whereas overexpression of Phospho1 reversed the anticalcific effect of NR4A3 deficiency in vascular smooth muscle cells. CONCLUSIONS: Taken together, our findings reveal that NR4A3-mediated histone lactylation is a novel metabolome-epigenome signaling cascade mechanism that participates in the pathogenesis of medial arterial calcification.
Subject(s)
Histones , Mice, Inbred C57BL , Mice, Knockout , Muscle, Smooth, Vascular , Nuclear Receptor Subfamily 4, Group A, Member 3 , Vascular Calcification , Animals , Vascular Calcification/metabolism , Vascular Calcification/genetics , Vascular Calcification/pathology , Mice , Humans , Histones/metabolism , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Nuclear Receptor Subfamily 4, Group A, Member 3/metabolism , Nuclear Receptor Subfamily 4, Group A, Member 3/genetics , Male , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Cells, Cultured , DNA-Binding Proteins , Nerve Tissue Proteins , Receptors, Steroid , Receptors, Thyroid HormoneABSTRACT
Cancer arises from malignant cells that exist in dynamic multilevel interactions with the host tissue. Cancer therapies aiming to directly kill cancer cells, including oncogene-targeted therapy and immune-checkpoint therapy that revives tumour-reactive cytotoxic T lymphocytes, are effective in some patients1,2, but acquired resistance frequently develops3,4. An alternative therapeutic strategy aims to rectify the host tissue pathology, including abnormalities in the vasculature that foster cancer progression5,6; however, neutralization of proangiogenic factors such as vascular endothelial growth factor A (VEGFA) has had limited clinical benefits7,8. Here, following the finding that transforming growth factor-ß (TGF-ß) suppresses T helper 2 (TH2)-cell-mediated cancer immunity9, we show that blocking TGF-ß signalling in CD4+ T cells remodels the tumour microenvironment and restrains cancer progression. In a mouse model of breast cancer resistant to immune-checkpoint or anti-VEGF therapies10,11, inducible genetic deletion of the TGF-ß receptor II (TGFBR2) in CD4+ T cells suppressed tumour growth. For pharmacological blockade, we engineered a bispecific receptor decoy by attaching the TGF-ß-neutralizing TGFBR2 extracellular domain to ibalizumab, a non-immunosuppressive CD4 antibody12,13, and named it CD4 TGF-ß Trap (4T-Trap). Compared with a non-targeted TGF-ß-Trap, 4T-Trap selectively inhibited TH cell TGF-ß signalling in tumour-draining lymph nodes, causing reorganization of tumour vasculature and cancer cell death, a process dependent on the TH2 cytokine interleukin-4 (IL-4). Notably, the 4T-Trap-induced tumour tissue hypoxia led to increased VEGFA expression. VEGF inhibition enhanced the starvation-triggered cancer cell death and amplified the antitumour effect of 4T-Trap. Thus, targeted TGF-ß signalling blockade in helper T cells elicits an effective tissue-level cancer defence response that can provide a basis for therapies directed towards the cancer environment.
Subject(s)
Breast Neoplasms/therapy , Immunotherapy , Signal Transduction/drug effects , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Helper-Inducer/immunology , Transforming Growth Factor beta/antagonists & inhibitors , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Breast Neoplasms/blood supply , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Cell Death/drug effects , Cell Hypoxia , Cell Line, Tumor , Female , HEK293 Cells , Humans , Interleukin-4/immunology , Lymph Nodes/cytology , Lymph Nodes/drug effects , Lymph Nodes/immunology , Male , Mice , Receptor, Transforming Growth Factor-beta Type II/chemistry , Receptor, Transforming Growth Factor-beta Type II/immunology , T-Lymphocytes, Helper-Inducer/metabolism , Transforming Growth Factor beta/immunology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/metabolismABSTRACT
RNA acetylation is a universal post-transcriptional modification that occurs in various RNAs. Transfer RNA (tRNA) acetylation is found at position 34 (ac4C34) in bacterial tRNAMet and position 12 (ac4C12) in eukaryotic tRNASer and tRNALeu. The biochemical mechanism, structural basis and functional significance of ac4C34 are well understood; however, despite being discovered in the 1960s and identification of Kre33/NAT10 and Tan1/THUMPD1 as modifying apparatuses, ac4C12 modification activity has never been reconstituted for nearly six decades. Here, we successfully reconstituted the ac4C12 modification activity of yeast Kre33 and Tan1. Biogenesis of ac4C12 is primarily dependent on a minimal set of elements, including a canonical acceptor stem, the presence of the 11CCG13 motif and correct D-arm orientation, indicating a molecular ruler mechanism. A single A13G mutation conferred ac4C12 modification to multiple non-substrate tRNAs. Moreover, we were able to introduce ac4C modifications into small RNAs. ac4C12 modification contributed little to tRNA melting temperature and aminoacylation in vitro and in vivo. Collectively, our results realize in vitro activity reconstitution, delineate tRNA substrate selection mechanism for ac4C12 biogenesis and develop a valuable system for preparing acetylated tRNAs as well as non-tRNA RNA species, which will advance the functional interpretation of the acetylation in RNA structures and functions.
Subject(s)
RNA, Transfer , RNA-Binding Proteins , Saccharomyces cerevisiae Proteins , Acetylation , Mutation , Nucleic Acid Conformation , RNA Processing, Post-Transcriptional , RNA, Transfer/metabolism , RNA, Transfer/genetics , RNA, Transfer/chemistry , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/chemistry , RNA-Binding Proteins/metabolismABSTRACT
Great progress has been made in identifying positive regulators that activate adipocyte thermogenesis, but negative regulatory signaling of thermogenesis remains poorly understood. Here, we found that cardiotrophin-like cytokine factor 1 (CLCF1) signaling led to loss of brown fat identity, which impaired thermogenic capacity. CLCF1 levels decreased during thermogenic stimulation but were considerably increased in obesity. Adipocyte-specific CLCF1 transgenic (CLCF1-ATG) mice showed impaired energy expenditure and severe cold intolerance. Elevated CLCF1 triggered whitening of brown adipose tissue by suppressing mitochondrial biogenesis. Mechanistically, CLCF1 bound and activated ciliary neurotrophic factor receptor (CNTFR) and augmented signal transducer and activator of transcription 3 (STAT3) signaling. STAT3 transcriptionally inhibited both peroxisome proliferator-activated receptor-γ coactivator (PGC) 1α and 1ß, which thereafter restrained mitochondrial biogenesis in adipocytes. Inhibition of CNTFR or STAT3 could diminish the inhibitory effects of CLCF1 on mitochondrial biogenesis and thermogenesis. As a result, CLCF1-TG mice were predisposed to develop metabolic dysfunction even without external metabolic stress. Our findings revealed a brake signal on nonshivering thermogenesis and suggested that targeting this pathway could be used to restore brown fat activity and systemic metabolic homeostasis in obesity.
Subject(s)
Adipocytes, Brown , Organelle Biogenesis , Animals , Mice , Adipocytes, Brown/metabolism , Adipose Tissue, Brown/metabolism , Homeostasis , Obesity/genetics , Obesity/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Thermogenesis/physiologyABSTRACT
BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) are prevalent birth defects. Although pathogenic CAKUT genes are known, they are insufficient to reveal the causes for all patients. Our previous studies indicated GEN1 as a pathogenic gene of CAKUT in mice, and this study further investigated the correlation between GEN1 and human CAKUT. METHODS: In this study, DNA from 910 individuals with CAKUT was collected; 26 GEN1 rare variants were identified, and two GEN1 (missense) variants in a non-CAKUT group were found. Mainly due to the stability results of the predicted mutant on the website, in vitro, 10 variants (eight CAKUT, two non-CAKUT) were selected to verify mutant protein stability. In addition, mainly based on the division of the mutation site located in the functional region of the GEN1 protein, 8 variants (six CAKUT, two non-CAKUT) were selected to verify enzymatic hydrolysis, and the splice variant GEN1 (c.1071 + 3(IVS10) A > G) was selected to verify shear ability. Based on the results of in vitro experiments and higher frequency, three sites with the most significant functional change were selected to build mouse models. RESULTS: Protein stability changed in six variants in the CAKUT group. Based on electrophoretic mobility shift assay of eight variants (six CAKUT, two non-CAKUT), the enzymatic hydrolysis and DNA-binding abilities of mutant proteins were impaired in the CAKUT group. The most serious functional damage was observed in the Gen1 variant that produced a truncated protein. A mini-gene splicing assay showed that the variant GEN1 (c.1071 + 3(IVS10) A > G) in the CAKUT group significantly affected splicing function. An abnormal exon10 was detected in the mini-gene splicing assay. Point-mutant mouse strains were constructed (Gen1: c.1068 + 3 A > G, p.R400X, and p.T105R) based on the variant frequency in the CAKUT group and functional impairment in vitro study and CAKUT phenotypes were replicated in each. CONCLUSION: Overall, our findings indicated GEN1 as a risk factor for human CAKUT.
Subject(s)
Urogenital Abnormalities , Vesico-Ureteral Reflux , Animals , Female , Humans , Male , Mice , Genetic Predisposition to Disease , Kidney/abnormalities , Kidney/pathology , Kidney/metabolism , Mutation/genetics , Protein Stability , Risk Factors , Urinary Tract/abnormalities , Urinary Tract/pathology , Urogenital Abnormalities/genetics , Urogenital Abnormalities/pathology , Vesico-Ureteral Reflux/genetics , Vesico-Ureteral Reflux/pathologyABSTRACT
APE1 is an essential gene involved in DNA damage repair, the redox regulation of transcriptional factors (TFs) and RNA processing. APE1 overexpression is common in cancers and correlates with poor patient survival. Stress granules (SGs) are phase-separated cytoplasmic assemblies that cells form in response to environmental stresses. Precise regulation of SGs is pivotal to cell survival, whereas their dysregulation is increasingly linked to diseases. Whether APE1 engages in modulating SG dynamics is worthy of investigation. In this study, we demonstrate that APE1 colocalizes with SGs and promotes their formation. Through phosphoproteome profiling, we discover that APE1 significantly alters the phosphorylation landscape of ovarian cancer cells, particularly the phosphoprofile of SG proteins. Notably, APE1 promotes the phosphorylation of Y-Box binding protein 1 (YBX1) at S174 and S176, leading to enhanced SG formation and cell survival. Moreover, expression of the phosphomutant YBX1 S174/176E mimicking hyperphosphorylation in APE1-knockdown cells recovered the impaired SG formation. These findings shed light on the functional importance of APE1 in SG regulation and highlight the importance of YBX1 phosphorylation in SG dynamics.
Subject(s)
DNA-(Apurinic or Apyrimidinic Site) Lyase , Ovarian Neoplasms , Stress Granules , Y-Box-Binding Protein 1 , Female , Humans , Endodeoxyribonucleases , Ovarian Neoplasms/genetics , Phosphorylation , Stress Granules/metabolism , Y-Box-Binding Protein 1/genetics , DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolismABSTRACT
Lithium hexafluorophosphate (LiPF6) has been the dominant conducting salt in lithium-ion battery (LIB) electrolytes for decades; however, it is extremely unstable in even trace water (ppm level). Interestingly, in pure water, PF6- does not undergo hydrolysis. Hereby, we present a fresh understanding of the mechanism involved in PF6- hydrolysis through theoretical and experimental explorations. In water, PF6- is found to be solvated by water, and this solvation greatly improved its hydrolytic stability; while in the electrolyte, it is forced to "float" due to the dissociation of its counterbalance ions. Its hydrolytic susceptibility arises from insufficient solvation-induced charge accumulation and high activity in electrophilic reactions with acidic species. Tuning the solvation environment, even by counterintuitively adding more water, could suppress PF6- hydrolysis. The undesired solvation of PF6- anions was attributed to the perennial LIB electrolyte system, and our findings are expected to inspire new thoughts regarding its design.
ABSTRACT
In ovarian cancer (OC), identifying key molecular players in disease escalation and chemoresistance remains critical. Our investigation elucidates the role of the DNA polymerase mu (POLM), especially G312R mutation, in propelling oncogenesis through dual pathways. POLMG312R markedly augments the ribonucleotide insertion capability of POLM, precipitating genomic instability. In addition, our research reveals that POLMG312R perturbs collagen alpha-1 (XI) chain (COL11A1) expression-a gene that plays a key role in oncogenesis-and modulates the NF-κB signaling pathway, alters the secretion of downstream inflammatory cytokines, and promotes tumor-macrophage interactions. We illustrate a bidirectional regulatory interaction between POLM, particularly its G312R variant, and COL11A1. This interaction regulates NF-κB signaling, culminating in heightened malignancy and resistance to chemotherapy in OC cells. These insights position the POLM as a potential molecular target for OC therapy, shedding light on the intricate pathways underpinning POLM variant disease progression.NEW & NOTEWORTHY Our research reveals that POLM plays an important role in ovarian cancer development, especially the mutation G312R. We uncover the POLMG312R mutation as a driver of genomic instability in ovarian cancer via aberrant ribonucleotide incorporation. We reveal that POLMG312R upregulates COL11A1 and activates NF-κB signaling, contributing to tumor progression and chemoresistance. This study identifies the POLM-COL11A1-NF-κB axis as a novel oncogenic pathway.
Subject(s)
Collagen Type XI , Genomic Instability , NF-kappa B , Ovarian Neoplasms , Signal Transduction , Female , Humans , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Ovarian Neoplasms/metabolism , Genomic Instability/genetics , NF-kappa B/metabolism , NF-kappa B/genetics , Collagen Type XI/genetics , Collagen Type XI/metabolism , Cell Line, Tumor , Carcinogenesis/genetics , Gene Expression Regulation, Neoplastic , Mutation , AnimalsABSTRACT
Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world's second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed.
Subject(s)
Brassica napus , Phylogeny , Plant Proteins , Brassica napus/genetics , Plant Proteins/genetics , Gene Expression Regulation, Plant , Multigene Family , Genome, Plant , Synteny , Gene Expression ProfilingABSTRACT
In social interaction, age-related differences in emotional processing may lead to varied social decision making between young and older adults. However, previous studies of social decision making have paid less attention to the interactants' emotions, leaving age differences and underlying neural mechanisms unexplored. To address this gap, the present study combined functional and structural magnetic resonance imaging, employing a modified dictator game task with recipients displaying either neutral or sad facial expressions. Behavioral results indicated that although older adults' overall allocations did not differ significantly from those of young adults, older adults' allocations showing a decrease in emotion-related generosity compared to young adults. Using representational similarity analysis, we found that older adults showed reduced neural representations of recipients' emotions and gray matter volume in the right anterior cingulate gyrus (ACC), right insula, and left dorsomedial prefrontal cortex (DMPFC) compared to young adults. More importantly, mediation analyses indicated that age influenced allocations not only through serial mediation of neural representations of the right insula and left DMPFC, but also through serial mediation of the mean gray matter volume of the right ACC and left DMPFC. This study identifies the potential neural pathways through which age affects emotion-related social decision making, advancing our understanding of older adults' social interaction behavior that they may not be less generous unless confronted with individuals with specific emotions.
Subject(s)
Aging , Decision Making , Emotions , Magnetic Resonance Imaging , Humans , Male , Female , Decision Making/physiology , Aged , Emotions/physiology , Young Adult , Adult , Aging/physiology , Facial Expression , Middle Aged , Gyrus Cinguli/diagnostic imaging , Gyrus Cinguli/physiology , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/physiology , Social Behavior , Brain/physiology , Brain/diagnostic imaging , Brain MappingABSTRACT
The pediatric International IgA Nephropathy (IgAN) Prediction Tool comprises two models with and without ethnicity and is the first method to predict the risk of a 30% decline in estimated glomerular filtration rate (eGFR) or kidney failure in children at the time of biopsy using clinical risk factors and Oxford MEST histology scores. However, it is unknown if the Prediction Tool can be applied after a period of observation post-biopsy. Using an international multi-ethnic cohort of 947 children with IgAN, 38% of whom were followed into adulthood, the Prediction Tool was updated for use one year after biopsy. Compared to the original pediatric Prediction Tool, the updated post-biopsy Prediction Tool had a better model fit with higher R2D (51%/50% vs 20%), significant increase in 4-year C-statistics (0.83 vs 0.73/0.69, ΔC 0.09 [95% confidence interval 0.07-0.10] and ΔC 0.14 [0.12-0.15]) and better 4-year calibration with lower integrated calibration indices (0.74/0.54 vs 2.45/1.01). Results were similar after internal validation and when the models were applied two years after biopsy. Trajectories of eGFR after a baseline one year post-biopsy were non-linear and those at higher predicted risk started with a lower eGFR and experienced a more rapid decline over time. In children, eGFR had a variable rate of increase until 15-18 years old and then decreased linearly with a more rapid decline in higher risk groups that was similar to young adults of comparable risk. Thus, the original pediatric Prediction Tool should be used in children at the time of biopsy, and the updated pediatric Prediction Tool should be used to re-evaluate risk one or two years after biopsy.
ABSTRACT
The homeostatic link between oxidative stress and autophagy plays an important role in cellular responses to a wide variety of physiological and pathological conditions. However, the regulatory pathway and outcomes remain incompletely understood. Here, we show that reactive oxygen species (ROS) function as signaling molecules that regulate autophagy through ataxia-telangiectasia mutated (ATM) and cell cycle checkpoint kinase 2 (CHK2), a DNA damage response (DDR) pathway activated during metabolic and hypoxic stress. We report that CHK2 binds to and phosphorylates Beclin 1 at Ser90/Ser93, thereby impairing Beclin 1-Bcl-2 autophagy-regulatory complex formation in a ROS-dependent fashion. We further demonstrate that CHK2-mediated autophagy has an unexpected role in reducing ROS levels via the removal of damaged mitochondria, which is required for cell survival under stress conditions. Finally, CHK2-/- mice display aggravated infarct phenotypes and reduced Beclin 1 p-Ser90/Ser93 in a cerebral stroke model, suggesting an in vivo role of CHK2-induced autophagy in cell survival. Taken together, these results indicate that the ROS-ATM-CHK2-Beclin 1-autophagy axis serves as a physiological adaptation pathway that protects cells exposed to pathological conditions from stress-induced tissue damage.
Subject(s)
Ataxia Telangiectasia Mutated Proteins/metabolism , Beclin-1/metabolism , Checkpoint Kinase 2/metabolism , Ischemic Stroke/metabolism , Reactive Oxygen Species/metabolism , Animals , Autophagy , Cell Line , Disease Models, Animal , HCT116 Cells , HEK293 Cells , HeLa Cells , Humans , Mice , Oxidative Stress , PhosphorylationABSTRACT
Rosacea, a prevalent chronic facial inflammatory condition, afflicts millions worldwide. Its multifaceted pathogenesis poses challenges for effective treatment. Tranilast (TR), an analog of a tryptophan metabolite, has demonstrated anti-inflammatory and anti-fibrotic properties across various diseases. Yet, its potential in rosacea treatment remains understudied. Here, we induced rosacea-like symptoms in mice via prolonged LL-37 injections and administered TR intervention. Our findings reveal that TR mitigated skin lesions, reduced skin thickness, and suppressed inflammatory cell infiltration within the dermis of LL-37 mice. Notably, TR downregulated the expression of rosacea-associated inflammatory cytokines (TNF-α, IL-6, IL-1ß, and IL-18) and the antimicrobial peptide CAMP, while also inhibiting NLRP3 inflammasome activation and the TLR4 signaling pathway. Furthermore, TR attenuated LL-37-induced fibrosis and hindered the transforming growth factor-ß1 (TGF-ß1)/Smad2/3 pathway. In summary, our study underscores TR's therapeutic potential in rosacea by mitigating both skin inflammation and fibrosis, thereby offering a promising treatment avenue for this condition.
ABSTRACT
Gestational diabetes mellitus (GDM) presents a substantial population health concern. Previous studies have revealed that GDM can ultimately influence nephron endowment. In this study, we established a GDM mouse model to investigate the embryological alterations and molecular mechanisms underlying the development of congenital anomalies of the kidney and urinary tract (CAKUT) affected by GDM. Our study highlights that GDM could contribute to the manifestation of CAKUT, with prevalent phenotypes characterized by isolated hydronephrosis and duplex kidney complicated with hydronephrosis in mice. Ectopic ureteric buds (UBs) and extended length of common nephric ducts (CNDs) were noted in the metanephric development stage. The expression of Ret and downstream p-ERK activity were enhanced in UBs, which indicated the alteration of RET/MAPK/ERK pathway may be one of the mechanisms contributing to the increased occurrence of CAKUT associated with GDM.
Subject(s)
Diabetes, Gestational , MAP Kinase Signaling System , Proto-Oncogene Proteins c-ret , Urogenital Abnormalities , Vesico-Ureteral Reflux , Animals , Female , Mice , Pregnancy , Diabetes, Gestational/metabolism , Kidney/abnormalities , Kidney/metabolism , Kidney/embryology , Proto-Oncogene Proteins c-ret/metabolism , Proto-Oncogene Proteins c-ret/genetics , Urinary Tract/abnormalities , Urinary Tract/embryology , Urogenital Abnormalities/etiology , Urogenital Abnormalities/genetics , Urogenital Abnormalities/pathologyABSTRACT
Rapeseed (Brassica napus L.) with short or no dormancy period are easy to germinate before harvest (pre-harvest sprouting, PHS). PHS has seriously decreased seed weight and oil content in B. napus. Short-chain dehydrogenase/ reductase (SDR) genes have been found to related to seed dormancy by promoting ABA biosynthesis in rice and Arabidopsis. In order to clarify whether SDR genes are the key factor of seed dormancy in B. napus, homology sequence blast, protein physicochemical properties, conserved motif, gene structure, cis-acting element, gene expression and variation analysis were conducted in present study. Results shown that 142 BnaSDR genes, unevenly distributed on 19 chromosomes, have been identified in B. napus genome. Among them, four BnaSDR gene clusters present in chromosome A04ãA05ãC03ãC04 were also identified. These 142 BnaSDR genes were divided into four subfamilies on phylogenetic tree. Members of the same subgroup have similar protein characters, conserved motifs, gene structure, cis-acting elements and tissue expression profiles. Specially, the expression levels of genes in subgroup A, B and C were gradually decreased, but increased in subgroup D with the development of seeds. Among seven higher expressed genes in group D, six BnaSDR genes were significantly higher expressed in weak dormancy line than that in nondormancy line. And the significant effects of BnaC01T0313900ZS and BnaC03T0300500ZS variation on seed dormancy were also demonstrated in present study. These findings provide a key information for investigating the function of BnaSDRs on seed dormancy in B. napus.
Subject(s)
Brassica napus , Brassica rapa , Brassica napus/genetics , Brassica napus/metabolism , Plant Dormancy/genetics , Gene Expression Profiling , Phylogeny , Brassica rapa/genetics , Seeds/genetics , Seeds/metabolism , Gene Expression Regulation, PlantABSTRACT
The introduction of noble metal into spinel structure is an effective strategy to develop efficient oxygen evolution/reduction reaction (OER/ORR) catalysts. Herein, surface Cooct is substituted by Ruoct in Rux-Mn0.5Co2.5-xO4/NCNTs by ion-exchange, where presence of RuoctâOâCooct unit facilitates electron transfer. This strong electron coupling effect leads downward shift in d-band center and a narrowing of d-p bandgap. The increased charge density of Cooct bridged with Ruoct dioxygen optimizes adsorption of oxygen intermediates (*OH) and occupation of electrons in eg-orbital octahedral. The measured ORR/OER voltage difference is only 0.71 V. The peak power density of assembled zinc-air battery reaches 148.8 mW h cm-2, and energy density at 100 mA cm-2 reaches 813.6 mA h gZn -1, approaching a theoretical value of 820 mA h gZn -1. The catalyst demonstrates stable operation for over 500 h at 10 mA cm-2 and over 200 h at 50 mA cm-2. This work provides new insights to guide fabrication of advanced oxygen electrocatalysts.
ABSTRACT
Based on the pathological characteristics of rheumatoid arthritis, including the overproduction of reactive oxygen species (ROS), inflammatory responses, and osteoclast differentiation, a biomimetic multifunctional nanomedicine (M-M@I) is designed. Iguratimod (IGU) is loaded, which inhibits inflammatory responses and osteoclast differentiation, into mesoporous polydopamine (MPDA), which scavenges ROS. Subsequently, the nanoparticles are coated with a cell membrane of macrophages to achieve actively targeted delivery of the nanoparticles to inflamed joints. It is shown that the M-M@I nanoparticles are taken up well by lipopolysaccharide-induced RAW 264.7 macrophages or bone marrow-derived macrophages (BMDMs). In vitro, the M-M@I nanoparticles effectively scavenge ROS, downregulate genes related to inflammation promotion and osteoclast differentiation, and reduce the proinflammatory cytokines and osteoclast-related enzymes. They also reduce the polarization of macrophages to a pro-inflammatory M1 phenotype and inhibit differentiation into osteoclasts. In mice with collagen-induced arthritis, the M-M@I nanoparticles accumulate at arthritic sites and circulate longer, significantly mitigating arthritis symptoms and bone destruction. These results suggest that the pathology-specific biomimetic multifunctional nanoparticles are effective against rheumatoid arthritis, and they validate the approach of developing multifunctional therapies that target various pathological processes simultaneously.