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1.
Annu Rev Biochem ; 2023 Nov 14.
Article in English | MEDLINE | ID: mdl-37963395

ABSTRACT

Cellular quality control systems sense and mediate homeostatic responses to prevent the buildup of aberrant macromolecules, which arise from errors during biosynthesis, damage by environmental insults, or imbalances in enzymatic and metabolic activity. Lipids are structurally diverse macromolecules that have many important cellular functions, ranging from structural roles in membranes to functions as signaling and energy-storage molecules. As with other macromolecules, lipids can be damaged (e.g., oxidized), and cells require quality control systems to ensure that nonfunctional and potentially toxic lipids do not accumulate. Ferroptosis is a form of cell death that results from the failure of lipid quality control and the consequent accumulation of oxidatively damaged phospholipids. In this review, we describe a framework for lipid quality control, using ferroptosis as an illustrative example to highlight concepts related to lipid damage, membrane remodeling, and suppression or detoxification of lipid damage via preemptive and damage-repair lipid quality control pathways. Expected final online publication date for the Annual Review of Biochemistry , Volume 93 is June 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

2.
Nature ; 615(7951): 285-291, 2023 03.
Article in English | MEDLINE | ID: mdl-36859541

ABSTRACT

The germline mutation rate determines the pace of genome evolution and is an evolving parameter itself1. However, little is known about what determines its evolution, as most studies of mutation rates have focused on single species with different methodologies2. Here we quantify germline mutation rates across vertebrates by sequencing and comparing the high-coverage genomes of 151 parent-offspring trios from 68 species of mammals, fishes, birds and reptiles. We show that the per-generation mutation rate varies among species by a factor of 40, with mutation rates being higher for males than for females in mammals and birds, but not in reptiles and fishes. The generation time, age at maturity and species-level fecundity are the key life-history traits affecting this variation among species. Furthermore, species with higher long-term effective population sizes tend to have lower mutation rates per generation, providing support for the drift barrier hypothesis3. The exceptionally high yearly mutation rates of domesticated animals, which have been continually selected on fecundity traits including shorter generation times, further support the importance of generation time in the evolution of mutation rates. Overall, our comparative analysis of pedigree-based mutation rates provides ecological insights on the mutation rate evolution in vertebrates.


Subject(s)
Evolution, Molecular , Germ-Line Mutation , Mutation Rate , Vertebrates , Animals , Female , Male , Birds/genetics , Fishes/genetics , Germ-Line Mutation/genetics , Mammals/genetics , Reptiles/genetics , Vertebrates/genetics
3.
FASEB J ; 38(14): e23808, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-38994637

ABSTRACT

Muscle development is a multistep process regulated by diverse gene networks, and circRNAs are considered novel regulators mediating myogenesis. Here, we systematically analyzed the role and underlying regulatory mechanisms of circRBBP7 in myoblast proliferation and differentiation. Results showed that circRBBP7 has a typical circular structure and encodes a 13 -kDa protein. By performing circRBBP7 overexpression and RNA interference, we found that the function of circRBBP7 was positively correlated with the proliferation and differentiation of myoblasts. Using RNA sequencing, we identified 1633 and 532 differentially expressed genes (DEGs) during myoblast proliferation or differentiation, respectively. The DEGs were found mainly enriched in cell cycle- and skeletal muscle development-related pathways, such as the MDM2/p53 and PI3K-Akt signaling pathways. Further co-IP and IF co-localization analysis revealed that VEGFR-1 is a target of circRBBP7 in myoblasts. qRT-PCR and WB analysis further confirmed the positive correlation between VEGFR-1 and circRBBP7. Moreover, we found that in vivo transfection of circRBBP7 into injured muscle tissues significantly promoted the regeneration and repair of myofibers in mice. Therefore, we speculate that circRBBP7 may affect the activity of MDM2 by targeting VEGFR-1, altering the expression of muscle development-related genes by mediating p53 degradation, and ultimately promoting myoblast development and muscle regeneration. This study provides essential evidence that circRBBP7 can serve as a potential target for myogenesis regulation and a reference for the application of circRBBP7 in cattle genetic breeding and muscle injury treatment.


Subject(s)
Cell Differentiation , Cell Proliferation , Muscle Development , Myoblasts , RNA, Circular , Animals , Male , Mice , Cell Line , Mice, Inbred C57BL , Muscle Development/physiology , Muscle, Skeletal/metabolism , Muscle, Skeletal/cytology , Myoblasts/metabolism , Myoblasts/cytology , Proto-Oncogene Proteins c-mdm2/metabolism , Proto-Oncogene Proteins c-mdm2/genetics , RNA, Circular/genetics , RNA, Circular/metabolism , Signal Transduction , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics
4.
Cell ; 141(6): 1042-55, 2010 Jun 11.
Article in English | MEDLINE | ID: mdl-20550938

ABSTRACT

The molecular understanding of autophagy has originated almost exclusively from yeast genetic studies. Little is known about essential autophagy components specific to higher eukaryotes. Here we perform genetic screens in C. elegans and identify four metazoan-specific autophagy genes, named epg-2, -3, -4, and -5. Genetic analysis reveals that epg-2, -3, -4, and -5 define discrete genetic steps of the autophagy pathway. epg-2 encodes a coiled-coil protein that functions in specific autophagic cargo recognition. Mammalian homologs of EPG-3/VMP1, EPG-4/EI24, and EPG-5/mEPG5 are essential for starvation-induced autophagy. VMP1 regulates autophagosome formation by controlling the duration of omegasomes. EI24 and mEPG5 are required for formation of degradative autolysosomes. This study establishes C. elegans as a multicellular genetic model to delineate the autophagy pathway and provides mechanistic insights into the metazoan-specific autophagic process.


Subject(s)
Autophagy , Caenorhabditis elegans/genetics , Animals , Caenorhabditis elegans/cytology , Caenorhabditis elegans/embryology , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/genetics , Cytoplasmic Granules/metabolism , Lysosomes/metabolism , Mutation , Phagosomes/metabolism
5.
Nature ; 575(7784): 688-692, 2019 11.
Article in English | MEDLINE | ID: mdl-31634900

ABSTRACT

Ferroptosis is a form of regulated cell death that is caused by the iron-dependent peroxidation of lipids1,2. The glutathione-dependent lipid hydroperoxidase glutathione peroxidase 4 (GPX4) prevents ferroptosis by converting lipid hydroperoxides into non-toxic lipid alcohols3,4. Ferroptosis has previously been implicated in the cell death that underlies several degenerative conditions2, and induction of ferroptosis by the inhibition of GPX4 has emerged as a therapeutic strategy to trigger cancer cell death5. However, sensitivity to GPX4 inhibitors varies greatly across cancer cell lines6, which suggests that additional factors govern resistance to ferroptosis. Here, using a synthetic lethal CRISPR-Cas9 screen, we identify ferroptosis suppressor protein 1 (FSP1) (previously known as apoptosis-inducing factor mitochondrial 2 (AIFM2)) as a potent ferroptosis-resistance factor. Our data indicate that myristoylation recruits FSP1 to the plasma membrane where it functions as an oxidoreductase that reduces coenzyme Q10 (CoQ) (also known as ubiquinone-10), which acts as a lipophilic radical-trapping antioxidant that halts the propagation of lipid peroxides. We further find that FSP1 expression positively correlates with ferroptosis resistance across hundreds of cancer cell lines, and that FSP1 mediates resistance to ferroptosis in lung cancer cells in culture and in mouse tumour xenografts. Thus, our data identify FSP1 as a key component of a non-mitochondrial CoQ antioxidant system that acts in parallel to the canonical glutathione-based GPX4 pathway. These findings define a ferroptosis suppression pathway and indicate that pharmacological inhibition of FSP1 may provide an effective strategy to sensitize cancer cells to ferroptosis-inducing chemotherapeutic agents.


Subject(s)
Apoptosis Regulatory Proteins/metabolism , Ferroptosis/genetics , Mitochondrial Proteins/metabolism , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Ubiquinone/analogs & derivatives , Animals , Apoptosis Regulatory Proteins/genetics , Cell Line, Tumor , Cell Membrane/metabolism , Gene Expression Regulation, Enzymologic , Heterografts , Humans , Lipid Peroxides/metabolism , Male , Mice , Mice, SCID , Mitochondrial Proteins/genetics , Ubiquinone/metabolism
6.
Cell Mol Life Sci ; 81(1): 96, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38372748

ABSTRACT

Activation of hepatic stellate cells (HSCs) has been demonstrated to play a pivotal role in the process of liver fibrogenesis. In this study, we observed a decrease in the expression of KIF18A in fibrotic liver tissues compared to healthy liver tissues, which exhibited a negative correlation with the activation of HSCs. To elucidate the molecular mechanisms underlying the involvement of KIF18A, we performed in vitro proliferation experiments and established a CCl4-induced liver fibrosis model. Our results revealed that KIF18A knockdown enhanced HSCs proliferation and reduced HSCs apoptosis in vitro. Mouse liver fibrosis grade was evaluated with Masson's trichrome and alpha-smooth muscle actin (α-SMA) staining. In addition, the expression of fibrosis markers Col1A1, Stat1, and Timp1 were detected. Animal experiments demonstrated that knockdown of KIF18A could promote liver fibrosis, whereas overexpression of KIF18A alleviated liver fibrosis in a CCl4-induced mouse model. Mechanistically, we found that KIF18A suppressed the AKT/mTOR pathway and exhibited direct binding to TTC3. Moreover, TTC3 was found to interact with p-AKT and could promote its ubiquitination and degradation. Our findings provide compelling evidence that KIF18A enhances the protein binding between TTC3 and p-AKT, promoting TTC3-mediated ubiquitination and degradation of p-AKT. These results refine the current understanding of the mechanisms underlying the pathogenesis of liver fibrosis and may offer new targets for treating this patient population.


Subject(s)
Hepatic Stellate Cells , Kinesins , Liver Cirrhosis , Animals , Humans , Mice , Kinesins/genetics , Liver Cirrhosis/chemically induced , Liver Cirrhosis/genetics , Proto-Oncogene Proteins c-akt , TOR Serine-Threonine Kinases , Ubiquitin-Protein Ligases
7.
Mol Biol Evol ; 40(1)2023 01 04.
Article in English | MEDLINE | ID: mdl-36585823

ABSTRACT

Pangolins are one of nature's most fascinating species being scales covered and myrmecophagous diet, yet relatively little is known about the molecular basis. Here, we combine the multi-omics, evolution, and fundamental proteins feature analysis of both Chinese and Malayan pangolins, highlighting the molecular mechanism of both myrmecophagous diet and scale formation, representing a fascinating evolutionary strategy to occupy the unique ecological niches. In contrast to conserved organization of epidermal differentiation complex, pangolin has undergone large scale variation and gene loss events causing expression pattern and function conversion that contribute to cornified epithelium structures on stomach to adapt myrmecophagous diet. Our assemblies also enable us to discover large copies number of high glycine-tyrosine keratin-associated proteins (HGT-KRTAPs). In addition, highly homogenized tandem array, amino content, and the specific expression pattern further validate the strong connection between the molecular mechanism of scale hardness and HGT-KRTAPs.


Subject(s)
Genome , Pangolins , Animals , Diet
8.
J Transl Med ; 22(1): 437, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38720345

ABSTRACT

BACKGROUND: Biological-derived hydroxyapatite is widely used as a bone substitute for addressing bone defects, but its limited osteoconductive properties necessitate further improvement. The osteo-immunomodulatory properties hold crucial promise in maintaining bone homeostasis, and precise modulation of macrophage polarization is essential in this process. Metabolism serves as a guiding force for immunity, and fluoride modification represents a promising strategy for modulating the osteoimmunological environment by regulating immunometabolism. In this context, we synthesized fluorinated porcine hydroxyapatite (FPHA), and has demonstrated its enhanced biological properties and osteogenic capacity. However, it remains unknown whether and how FPHA affects the immune microenvironment of the bone defects. METHODS: FPHA was synthesized and its composition and structural properties were confirmed. Macrophages were cultured with FPHA extract to investigate the effects of FPHA on their polarization and the related osteo-immune microenvironment. Furthermore, total RNA of these macrophages was extracted, and RNA-seq analysis was performed to explore the underlying mechanisms associated with the observed changes in macrophages. The metabolic states were evaluated with a Seahorse analyzer. Additionally, immunohistochemical staining was performed to evaluate the macrophages response after implantation of the novel bone substitutes in critical size calvarial defects in SD rats. RESULTS: The incorporation of fluoride ions in FPHA was validated. FPHA promoted macrophage proliferation and enhanced the expression of M2 markers while suppressing the expression of M1 markers. Additionally, FPHA inhibited the expression of inflammatory factors and upregulated the expression of osteogenic factors, thereby enhancing the osteogenic differentiation capacity of the rBMSCs. RNA-seq analysis suggested that the polarization-regulating function of FPHA may be related to changes in cellular metabolism. Further experiments confirmed that FPHA enhanced mitochondrial function and promoted the metabolic shift of macrophages from glycolysis to oxidative phosphorylation. Moreover, in vivo experiments validated the above results in the calvarial defect model in SD rats. CONCLUSION: In summary, our study reveals that FPHA induces a metabolic shift in macrophages from glycolysis to oxidative phosphorylation. This shift leads to an increased tendency toward M2 polarization in macrophages, consequently creating a favorable osteo-immune microenvironment. These findings provide valuable insights into the impact of incorporating an appropriate concentration of fluoride on immunometabolism and macrophage mitochondrial function, which have important implications for the development of fluoride-modified immunometabolism-based bone regenerative biomaterials and the clinical application of FPHA or other fluoride-containing materials.


Subject(s)
Durapatite , Glycolysis , Macrophages , Oxidative Phosphorylation , Rats, Sprague-Dawley , Animals , Durapatite/chemistry , Macrophages/metabolism , Macrophages/drug effects , Oxidative Phosphorylation/drug effects , Glycolysis/drug effects , Rats , Swine , Cell Proliferation/drug effects , Male , Osteogenesis/drug effects , Skull/pathology , Skull/drug effects , Mice , Cellular Microenvironment/drug effects , RAW 264.7 Cells , Bone and Bones/metabolism , Bone and Bones/drug effects
9.
Clin Exp Allergy ; 54(6): 412-424, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38639267

ABSTRACT

BACKGROUND: SERPINB2, a biomarker of Type-2 (T2) inflammatory processes, has been described in the context of asthma. Chronic rhinosinusitis with nasal polyps (CRSwNP) is also correlated with T2 inflammation and elevated 15LO1 induced by IL-4/13 in nasal epithelial cells. The aim of this study was to evaluate the expression and location of SERPINB2 in nasal epithelial cells (NECs) and determine whether SERPINB2 regulates 15LO1 and downstream T2 markers in NECs via STAT6 signalling. METHODS: SERPINB2 gene expression in bulk and single-cell RNAseq database was analysed by bioinformatics analysis. SERPINB2, 15LO1 and other T2 markers were evaluated from CRSwNP and HCs NECs. The colocalization of SERPINB2 and 15LO1 was evaluated by immunofluorescence. Fresh NECs were cultured at an air-liquid interface with or without IL-13, SERPINB2 Dicer-substrate short interfering RNAs (DsiRNAs) transfection, exogenous SERPINB2, 15-HETE recombinant protein and pSTAT6 inhibitors. 15LO1, 15-HETE and downstream T2 markers were analysed by qRT-PCR, western blot and ELISA. RESULTS: SERPINB2 expression was increased in eosinophilic nasal polyps compared with that in noneosinophilic nasal polyps and control tissues and positively correlated with 15LO1 and other downstream T2 markers. SERPINB2 was predominantly expressed by epithelial cells in NP tissue and was colocalized with 15LO1. In primary NECs in vitro, SERPINB2 expression was induced by IL-13. Knockdown or overexpression SERPINB2 decreased or enhanced expression of 15LO1 and 15-HETE in NECs, respectively, in a STAT6-dependent manner. SERPINB2 siRNA also inhibited the expression of the 15LO1 downstream genes, such as CCL26, POSTN and NOS2. STAT6 inhibition similarly decreased SERPINB2-induced 15LO1. CONCLUSIONS: SERPINB2 is increased in NP epithelial cells of eosinophilic CRSwNP (eCRSwNP) and contributes to T2 inflammation via STAT6 signalling. SERPINB2 could be considered a novel therapeutic target for eCRSwNP.


Subject(s)
Epithelial Cells , Nasal Polyps , Rhinitis , STAT6 Transcription Factor , Signal Transduction , Sinusitis , Humans , STAT6 Transcription Factor/metabolism , STAT6 Transcription Factor/genetics , Nasal Polyps/metabolism , Nasal Polyps/pathology , Nasal Polyps/immunology , Sinusitis/metabolism , Sinusitis/pathology , Sinusitis/immunology , Rhinitis/metabolism , Rhinitis/pathology , Chronic Disease , Epithelial Cells/metabolism , Plasminogen Activator Inhibitor 2/metabolism , Plasminogen Activator Inhibitor 2/genetics , Female , Male , Chemokine CCL26/metabolism , Chemokine CCL26/genetics , Adult , Middle Aged , Eosinophilia/metabolism , Eosinophilia/pathology , Nasal Mucosa/metabolism , Nasal Mucosa/pathology , Nasal Mucosa/immunology , Gene Expression Regulation , Rhinosinusitis
10.
Plant Physiol ; 191(4): 2519-2533, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36715300

ABSTRACT

ABSCISIC ACID-INSENSITIVE3 (ABI3) and ABI5 are 2 crucial transcription factors in abscisic acid (ABA) signaling, and their homeostasis at the protein level plays a decisive role in seed germination and subsequent seedling growth. Here, we found that PLANT U-BOX 8 (PUB8), a U-box E3 ubiquitin ligase, physically interacts with ABI3 and ABI5 and negatively regulates ABA responses during early Arabidopsis (Arabidopsis thaliana) seedling growth. Loss-of-function pub8 mutants were hypersensitive to ABA-inhibited cotyledon greening, while lines overexpressing PUB8 with low levels of ABI5 protein abundance were insensitive to ABA. Genetic analyses showed that ABI3 and ABI5 were required for the ABA-sensitive phenotype of pub8, indicating that PUB8 functions upstream of ABI3 and ABI5 to regulate ABA responses. Biochemical analyses showed that PUB8 can associate with ABI3 and ABI5 for degradation through the ubiquitin-mediated 26S proteasome pathway. Correspondingly, loss-of-function of PUB8 led to enhanced ABI3 and ABI5 stability, while overexpression of PUB8 impaired accumulation of ABI3 and ABI5 in planta. Further phenotypic analysis indicated that PUB8 compromised the function of ABI5 during early seedling growth. Taken together, our results reveal the regulatory role of PUB8 in modulating the early seedling growth by controlling the homeostasis of ABI3 and ABI5.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Abscisic Acid/pharmacology , Abscisic Acid/metabolism , Seedlings/metabolism , Arabidopsis Proteins/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Basic-Leucine Zipper Transcription Factors/genetics , Basic-Leucine Zipper Transcription Factors/metabolism , Germination/genetics , Signal Transduction , Arabidopsis/metabolism , Gene Expression Regulation, Plant , Seeds/genetics
11.
Glob Chang Biol ; 30(7): e17411, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39001641

ABSTRACT

Humans have substantially transformed the global land surface, resulting in the decline in variation in biotic communities across scales, a phenomenon known as "biological homogenization." However, different biota are affected by biological homogenization to varying degrees, but this variation and the underlying mechanisms remain little studied, particularly in soil systems. To address this topic, we used metabarcoding to investigate the biogeography of soil protists and their prey/hosts (prokaryotes, fungi, and meso- and macrofauna) in three human land-use ecosystem types (farmlands, residential areas, and parks) and natural forest ecosystems across subtropical and temperate regions in China. Our results showed that the degree of community homogenization largely differed between taxa and functional groups of soil protists, and was strongly and positively linked to their colonization ability of human land-use systems. Removal analysis showed that the introduction of widespread, generalist taxa (OTUs, operational taxonomic units) rather than the loss of narrow-ranged, specialist OTUs was the major cause of biological homogenization. This increase in generalist OTUs seemingly alleviated the negative impact of land use on specialist taxa, but carried the risk of losing functional diversity. Finally, homogenization of prey/host biota and environmental conditions were also important drivers of biological homogenization in human land-use systems, with their importance being more pronounced in phagotrophic than parasitic and phototrophic protists. Overall, our study showed that the variation in biological homogenization strongly depends on the colonization ability of taxa in human land-use systems, but is also affected by the homogenization of resources and environmental conditions. Importantly, biological homogenization is not the major cause of the decline in the diversity of soil protists, and conservation and study efforts should target at taxa highly sensitive to local extinction, such as parasites.


Subject(s)
Biodiversity , Soil , China , Soil/chemistry , Ecosystem , Soil Microbiology , Human Activities , Humans , Fungi , Forests
12.
Opt Lett ; 49(11): 2886-2889, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824284

ABSTRACT

Light field (LF) imaging has gained significant attention in the field of computational imaging due to its unique capability to capture both spatial and angular information of a scene. In recent years, super-resolution (SR) techniques based on deep learning have shown considerable advantages in enhancing LF image resolution. However, the inherent challenges of obtaining rich structural information and reconstructing complex texture details persist, particularly in scenarios where spatial and angular information are intricately interwoven. This Letter introduces a novel, to the best of our knowledge, approach for Disentangling LF Image SR Network (DLISN) by leveraging the synergy of dual learning and Fourier channel attention (FCA) mechanisms. Dual learning strategies are employed to enhance reconstruction results, addressing limitations in model generalization caused by the difficulty in acquiring paired datasets in real-world LF scenarios. The integration of FCA facilitates the extraction of high-frequency information associated with different structures, contributing to improved spatial resolution. Experimental results consistently demonstrate superior performance in enhancing the resolution of LF images.

13.
Crit Rev Biotechnol ; : 1-19, 2024 May 26.
Article in English | MEDLINE | ID: mdl-38797672

ABSTRACT

Astaxanthin, a ketone carotenoid known for its high antioxidant activity, holds significant potential for application in nutraceuticals, aquaculture, and cosmetics. The increasing market demand necessitates a higher production of astaxanthin using Phaffia rhodozyma. Despite extensive research efforts focused on optimizing fermentation conditions, employing mutagenesis treatments, and utilizing genetic engineering technologies to enhance astaxanthin yield in P. rhodozyma, progress in this area remains limited. This review provides a comprehensive summary of the current understanding of rough metabolic pathways, regulatory mechanisms, and preliminary strategies for enhancing astaxanthin yield. However, further investigation is required to fully comprehend the intricate and essential metabolic regulation mechanism underlying astaxanthin synthesis. Specifically, the specific functions of key genes, such as crtYB, crtS, and crtI, need to be explored in detail. Additionally, a thorough understanding of the action mechanism of bifunctional enzymes and alternative splicing products is imperative. Lastly, the regulation of metabolic flux must be thoroughly investigated to reveal the complete pathway of astaxanthin synthesis. To obtain an in-depth mechanism and improve the yield of astaxanthin, this review proposes some frontier methods, including: omics, genome editing, protein structure-activity analysis, and synthetic biology. Moreover, it further elucidates the feasibility of new strategies using these advanced methods in various effectively combined ways to resolve these problems mentioned above. This review provides theory and method for studying the metabolic pathway of astaxanthin in P. rhodozyma and the industrial improvement of astaxanthin, and provides new insights into the flexible combined use of multiple modern advanced biotechnologies.

14.
Nat Chem Biol ; 18(7): 751-761, 2022 07.
Article in English | MEDLINE | ID: mdl-35637349

ABSTRACT

The selenoprotein glutathione peroxidase 4 (GPX4) prevents ferroptosis by converting lipid peroxides into nontoxic lipid alcohols. GPX4 has emerged as a promising therapeutic target for cancer treatment, but some cancer cells are resistant to ferroptosis triggered by GPX4 inhibition. Using a chemical-genetic screen, we identify LRP8 (also known as ApoER2) as a ferroptosis resistance factor that is upregulated in cancer. Loss of LRP8 decreases cellular selenium levels and the expression of a subset of selenoproteins. Counter to the canonical hierarchical selenoprotein regulatory program, GPX4 levels are strongly reduced due to impaired translation. Mechanistically, low selenium levels result in ribosome stalling at the inefficiently decoded GPX4 selenocysteine UGA codon, leading to ribosome collisions, early translation termination and proteasomal clearance of the N-terminal GPX4 fragment. These findings reveal rewiring of the selenoprotein hierarchy in cancer cells and identify ribosome stalling and collisions during GPX4 translation as ferroptosis vulnerabilities in cancer.


Subject(s)
Ferroptosis , Selenium , Phospholipid Hydroperoxide Glutathione Peroxidase , Ribosomes/metabolism , Selenium/metabolism , Selenium/pharmacology , Selenoproteins/genetics
15.
J Pineal Res ; 76(5): e12987, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38975671

ABSTRACT

Sleep deprivation (SD) has been associated with a plethora of severe pathophysiological syndromes, including gut damage, which recently has been elucidated as an outcome of the accumulation of reactive oxygen species (ROS). However, the spatiotemporal analysis conducted in this study has intriguingly shown that specific events cause harmful damage to the gut, particularly to goblet cells, before the accumulation of lethal ROS. Transcriptomic and metabolomic analyses have identified significant enrichment of metabolites related to ferroptosis in mice suffering from SD. Further analysis revealed that melatonin could rescue the ferroptotic damage in mice by suppressing lipid peroxidation associated with ALOX15 signaling. ALOX15 knockout protected the mice from the serious damage caused by SD-associated ferroptosis. These findings suggest that melatonin and ferroptosis could be targets to prevent devastating gut damage in animals exposed to SD. To sum up, this study is the first report that proposes a noncanonical modulation in SD-induced gut damage via ferroptosis with a clearly elucidated mechanism and highlights the active role of melatonin as a potential target to maximally sustain the state during SD.


Subject(s)
Ferroptosis , Melatonin , Mice, Knockout , Sleep Deprivation , Animals , Mice , Melatonin/metabolism , Melatonin/pharmacology , Sleep Deprivation/metabolism , Male , Reactive Oxygen Species/metabolism , Mice, Inbred C57BL , Lipid Peroxidation , Arachidonate 15-Lipoxygenase/metabolism , Arachidonate 15-Lipoxygenase/genetics , Arachidonate 12-Lipoxygenase
16.
Nanotechnology ; 35(12)2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38100843

ABSTRACT

Mucosal delivery systems have gained much attention as effective way for antigen delivery that induces both systemic and mucosal immunity. However, mucosal vaccination faces the challenges of mucus barrier and effective antigen uptake and presentation. In particular, split, subunit and recombinant protein vaccines that do not have an intact pathogen structure lack the efficiency to stimulate mucosal immunity. In this study, poly (lactic acid-co-glycolic acid-polyethylene glycol) (PLGA-PEG) block copolymers were modified by mannose to form a PLGA-PEG-Man conjugate (mannose modified PLGA-PEG), which were characterized. The novel nanoparticles (NPs) prepared with this material had a particle size of about 150 nm and a zeta potential of -15 mV, and possessed ideal mucus permeability, immune cell targeting, stability and low toxicity. Finally, PLGA-PEG-Man nanoparticles (PLGA-PEG-Man NPs) were successfully applied for intranasal delivery of split influenza vaccine in rat for the first time, which triggered strong systemic and mucosal immune responses. These studies suggest that PLGA-PEG-Man NPs could function as competitive potential nano-adjuvants to address the challenge of inefficient mucosal delivery of non-allopathogenic antigens.


Subject(s)
Influenza Vaccines , Nanoparticles , Humans , Rats , Animals , Polylactic Acid-Polyglycolic Acid Copolymer , Polyglycolic Acid/chemistry , Lactic Acid/chemistry , Mannose , Adjuvants, Immunologic/pharmacology , Antigens , Nanoparticles/chemistry
17.
Mol Biol Rep ; 51(1): 795, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39001907

ABSTRACT

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a disease of unknown etiology characterized by a constant incidence rate. Unfortunately, effective pharmacological treatments for this condition are lacking and the identification of novel therapeutic approaches and underlying pathological mechanisms are required. This study investigated the potential of quercetin in alleviating pulmonary fibrosis by promoting autophagy and activation of the SIRT1/AMPK pathway. METHODS: Mouse models of IPF were divided into four treatment groups: control, bleomycin (BLM), quercetin (Q), and quercetin + EX-527 (Q + E) treatment. Pulmonary fibrosis was induced in the mouse models through intratracheal instillation of BLM. Various indexes were identified through histological staining, Western blotting analysis, enzyme-linked immunosorbent assay, immunohistochemistry, and transmission electron microscopy. RESULTS: Quercetin treatment ameliorated the pathology of BLM-induced pulmonary fibrosis of mice by reducing α-smooth muscle actin (α-SMA), collagen I (Col I), and collagen III (Col III) levels, and also improved the level of E-cadherin in lung tissue. Furthermore, Quercetin significantly enhanced LC3II/LC3I levels, decreased P62 expression, and increased the number of autophagosomes in lung tissue. These effects were accompanied by the activation of the SIRT1/AMPK pathway. Treatment with EX-527, an inhibitor for SIRT1, reversed all effects induced by quercetin. CONCLUSION: This study showed that quercetin could alleviate pulmonary fibrosis and improve epithelial-mesenchymal transition by acting on the SIRT1/AMPK signaling pathway, which may be achieved by regulating the level of autophagy.


Subject(s)
AMP-Activated Protein Kinases , Autophagy , Bleomycin , Pulmonary Fibrosis , Quercetin , Signal Transduction , Sirtuin 1 , Animals , Bleomycin/adverse effects , Quercetin/pharmacology , Sirtuin 1/metabolism , Autophagy/drug effects , Signal Transduction/drug effects , Mice , AMP-Activated Protein Kinases/metabolism , Pulmonary Fibrosis/drug therapy , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/pathology , Disease Models, Animal , Male , Lung/drug effects , Lung/pathology , Lung/metabolism , Epithelial-Mesenchymal Transition/drug effects , Idiopathic Pulmonary Fibrosis/drug therapy , Idiopathic Pulmonary Fibrosis/metabolism , Idiopathic Pulmonary Fibrosis/chemically induced , Idiopathic Pulmonary Fibrosis/pathology , Mice, Inbred C57BL
18.
Cell ; 136(2): 308-21, 2009 Jan 23.
Article in English | MEDLINE | ID: mdl-19167332

ABSTRACT

How autophagy, an evolutionarily conserved intracellular catabolic system for bulk degradation, selectively degrades protein aggregates is poorly understood. Here, we show that several maternally derived germ P granule components are selectively eliminated by autophagy in somatic cells during C. elegans embryogenesis. The activity of sepa-1 is required for the degradation of these P granule components and for their accumulation into aggregates, termed PGL granules, in autophagy mutants. SEPA-1 forms protein aggregates and is also a preferential target of autophagy. SEPA-1 directly binds to the P granule component PGL-3 and also to the autophagy protein LGG-1/Atg8. SEPA-1 aggregates consistently colocalize with PGL granules and with LGG-1 puncta. Thus, SEPA-1 functions as a bridging molecule in mediating the specific recognition and degradation of P granule components by autophagy. Our study reveals a mechanism for preferential degradation of protein aggregates by autophagy and emphasizes the physiological significance of selective autophagy during animal development.


Subject(s)
Autophagy , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/cytology , Caenorhabditis elegans/embryology , Carrier Proteins/metabolism , Cytoplasmic Granules/metabolism , Amino Acid Sequence , Animals , Caenorhabditis elegans/metabolism , Caenorhabditis elegans Proteins/chemistry , Caenorhabditis elegans Proteins/genetics , Carrier Proteins/chemistry , Carrier Proteins/genetics , Disorders of Sex Development , Extrachromosomal Inheritance , Male , Molecular Sequence Data , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism
19.
Eur J Clin Pharmacol ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963453

ABSTRACT

BACKGROUND AND OBJECTIVE: Multiple randomized controlled studies have shown that pirfenidone and nintedanib are effective and safe for treating idiopathic pulmonary fibrosis. This study aimed to evaluate their efficacy, safety, and tolerability in a real-world setting. METHODS: We searched PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases for real-world studies published up to March 3, 2023, on pirfenidone and nintedanib for idiopathic pulmonary fibrosis. RESULTS: A total of 74 studies with 23,119 participants were included. After 12 months of treatment, the change from baseline in percent predicted FVC (%FVC) was - 0.75% for pirfenidone and - 1.43% for nintedanib. The change from baseline in percent predicted DLCO (%DCLO) was - 2.32% for pirfenidone and - 3.95% for nintedanib. The incidence of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) was 12.5% for pirfenidone and 14.4% for nintedanib. The IPF-related mortality rates of pirfenidone and nintedanib were 13.4% and 7.2%, respectively. The all-cause mortality was 20.1% for pirfenidone and 16.6% for nintedanib. In the pirfenidone group, 16.6% of patients discontinued treatment because of adverse events, and in the nintedanib group, 16.2% of patients discontinued treatment because of adverse events. The incidence of adverse events was 56.4% and 69.7% for pirfenidone and nintedanib, respectively. CONCLUSION: The results of this study indicate that pirfenidone and nintedanib are both effective in slowing down the decline of lung function in IPF patients in real-world settings. The incidence of adverse events with pirfenidone is lower than that with nintedanib, but both are below the clinical trial data, and no new major adverse events have been observed. The discontinuation rates due to adverse reactions of the two drugs are consistent with clinical trial data, indicating good tolerability. However, the mortality rates and AE-IPF incidence rates of these two drugs in real-world settings are higher than those in previous clinical trials, with pirfenidone patients showing a higher mortality rate. Further large-sample studies are needed to investigate the risks of these drugs in these aspects. Additionally, we recommend that future real-world studies pay more attention to patients' subjective symptoms and conduct stratified analyses of the efficacy and safety of pirfenidone and nintedanib based on factors such as patients' baseline lung function, comorbidities, and age, in order to provide more personalized medication advice for IPF patients in clinical practice.

20.
BMC Cardiovasc Disord ; 24(1): 60, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38243161

ABSTRACT

BACKGROUND: The triglyceride glucose-body mass index (TyG-BMI index) has been suggested as a novel predictor of insulin resistance. However, its predictive value for slow coronary flow phenomenon (SCFP) in patients with ischemia and nonobstructive coronary arteries (INOCA) remains unclear. METHODS: We consecutively recruited 1625 patients with INOCA from February 2019 to February 2023 and divided them into two groups based on thrombolysis in myocardial infarction (TIMI) frame counts (TFCs): the SCFP group (n = 79) and the control group. A 1:2 age-matched case-control study was then performed. The TyG-BMI index was calculated as ln [plasma triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI. RESULTS: TyG-BMI index in the SCFP group (218.3 ± 25.2 vs 201.0 ± 26.5, P < .001) was significantly higher than in the normal controls. TyG-BMI index also increased with the number of coronary arteries involved in the SCFP. Multivariate logistic regression analysis showed that TyG-BMI, BMI, and TG were independent predictors for SCFP. Receiver operating characteristic (ROC) curve analysis showed that when the TyG-BMI index was above 206.7, the sensitivity and specificity were 88.6% and 68.5%, respectively, with an AUC of 0.809 (95% CI: 0.756-0.863, P = .027). Combined BMI with TG, the TyG-BMI index had a better predictive value for SCFP than BMI and TG (P < .001). CONCLUSION: The TyG-BMI index was an independent predictor for SCFP in INOCA patients, and it had a better predictive value than BMI and TG.


Subject(s)
Glucose , No-Reflow Phenomenon , Humans , Body Mass Index , Blood Glucose , Coronary Vessels , Triglycerides , Case-Control Studies , Biomarkers , Ischemia , No-Reflow Phenomenon/diagnostic imaging , No-Reflow Phenomenon/etiology
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