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Nutrients Jun 2024Iron deficiency is the number one nutritional problem worldwide. Iron uptake is regulated at the intestine and is highly influenced by the gut microbiome. Blood from the...
Iron deficiency is the number one nutritional problem worldwide. Iron uptake is regulated at the intestine and is highly influenced by the gut microbiome. Blood from the intestines drains directly into the liver, informing iron status and gut microbiota status. Changes in either iron or the microbiome are tightly correlated with the development of metabolic dysfunction-associated steatotic liver disease (MASLD). To investigate the underlying mechanisms of the development of MASLD that connect altered iron metabolism and gut microbiota, we compared specific pathogen free (SPF) or germ-free (GF) mice, fed a normal or low-iron diet. SPF mice on a low-iron diet showed reduced serum triglycerides and MASLD. In contrast, GF low-iron diet-fed mice showed increased serum triglycerides and did not develop hepatic steatosis. SPF mice showed significant changes in liver lipid metabolism and increased insulin resistance that was dependent upon the presence of the gut microbiota. We report that total body loss of mitochondrial iron importer Mitoferrin2 () exacerbated the development of MASLD on a low-iron diet with significant lipid metabolism alterations. Our study demonstrates a clear contribution of the gut microbiome, dietary iron, and Mfrn2 in the development of MASLD and metabolic syndrome.
Topics: Animals; Gastrointestinal Microbiome; Mice; Liver; Fatty Liver; Lipid Metabolism; Iron, Dietary; Male; Mice, Inbred C57BL; Triglycerides; Iron; Mitochondria; Mitochondrial Proteins; Insulin Resistance; Mice, Knockout; Iron Deficiencies
PubMed: 38931165
DOI: 10.3390/nu16121804 -
Animals : An Open Access Journal From... Jun 2024Avian metapneumovirus (aMPV) has been identified as an important cause of respiratory and reproductive disease, leading to significant productive losses worldwide....
Avian metapneumovirus (aMPV) has been identified as an important cause of respiratory and reproductive disease, leading to significant productive losses worldwide. Different subtypes have been found to circulate in different regions, with aMPV-A and B posing a significant burden especially in the Old World, and aMPV-C in North America, albeit with limited exceptions of marginal economic relevance. Recently, both aMPV-A and aMPV-B have been reported in the U.S.; however, the route of introduction has not been investigated. In the present study, the potential importation pathways have been studied through phylogenetic and phylodynamic analyses based on a broad collection of partial attachment (G) protein sequences collected worldwide. aMPV-B circulating in the U.S. seems the descendant of Eastern Asian strains, which, in turn, are related to European ones. A likely introduction pathway mediated by wild bird migration through the Beringian crucible, where the East Asian and Pacific American flight paths intersect, appears likely and was previously reported for avian influenza. aMPV-A, on the other hand, showed a Mexican origin, involving strains related to Asian ones. Given the low likelihood of trade or illegal importation, the role of wild birds appears probable also in this case, since the region is covered by different flight paths directed in a North-South direction through America. Since the information on the role of wild birds in aMPV epidemiology is still scarce and scattered, considering the significant practical implications for the poultry industry demonstrated by recent U.S. outbreaks, further surveys on wild birds are encouraged.
PubMed: 38929405
DOI: 10.3390/ani14121786 -
Foods (Basel, Switzerland) Jun 2024Cassava is a staple crop in developing countries because its starchy roots provide essential dietary carbohydrates. The aim of this research was to conduct a...
Cassava is a staple crop in developing countries because its starchy roots provide essential dietary carbohydrates. The aim of this research was to conduct a comprehensive inquiry and scientific evaluation of the nutritional value of cassava tubers. Eight nutritional characteristics were examined in native and imported cassava variants: starch, reduced sugar, anthocyanins, protein, dietary fiber, quinic acid, vitamin C, and dry matter content. Principal component analysis (PCA) was conducted to minimize the dimensionality of the nutritional markers. A scientific assessment technique was developed to calculate a composite score for the various cassava samples. Analysis of the data revealed noticeable variance among the samples' nutritional indicators, suggesting varying degrees of association. Starch had a substantial positive link with lower sugar, protein, and dry matter content ( < 0.01). Anthocyanins and quinic acid interacted favorably ( < 0.05), and a positive link between protein and dry matter content was observed ( < 0.05); however, protein and dietary fiber interacted negatively ( < 0.05). The contribution rate of the top three PCA factors was over 76%, demonstrating that these factors incorporated the primary information acquired from the eight original nutritional indices, while maintaining excellent representativeness and impartiality. The experimental results showed a preliminary nutritional grade for 22 cassava tuber samples. The top five types were Guangxi Muci, Gui Cassava 4, Glutinous Rice Cassava, Huifeng 60, and Dongguan Hongwei. In the cluster analysis, the levels of similarity between the data showed that the 22 types of cassava tubers could be grouped into five categories, each with their own set of nutrients. This study promotes the directed breeding of cassava species and offers a theoretical foundation for creating and using various cassava varieties. Furthermore, this work lays the groundwork for a systematic and dependable technique for the quality assessment, comprehensive evaluation, and reasonable classification of cassava species and similar crops.
PubMed: 38928804
DOI: 10.3390/foods13121861 -
Genes May 2024LONP1 is the principal AAA+ unfoldase and bulk protease in the mitochondrial matrix, so its deletion causes embryonic lethality. The AAA+ unfoldase CLPX and the... (Review)
Review
Knockout Mouse Studies Show That Mitochondrial CLPP Peptidase and CLPX Unfoldase Act in Matrix Condensates near IMM, as Fast Stress Response in Protein Assemblies for Transcript Processing, Translation, and Heme Production.
LONP1 is the principal AAA+ unfoldase and bulk protease in the mitochondrial matrix, so its deletion causes embryonic lethality. The AAA+ unfoldase CLPX and the peptidase CLPP also act in the matrix, especially during stress periods, but their substrates are poorly defined. Mammalian CLPP deletion triggers infertility, deafness, growth retardation, and cGAS-STING-activated cytosolic innate immunity. CLPX mutations impair heme biosynthesis and heavy metal homeostasis. CLPP and CLPX are conserved from bacteria to humans, despite their secondary role in proteolysis. Based on recent proteomic-metabolomic evidence from knockout mice and patient cells, we propose that CLPP acts on phase-separated ribonucleoprotein granules and CLPX on multi-enzyme condensates as first-aid systems near the inner mitochondrial membrane. Trimming within assemblies, CLPP rescues stalled processes in mitoribosomes, mitochondrial RNA granules and nucleoids, and the D-foci-mediated degradation of toxic double-stranded mtRNA/mtDNA. Unfolding multi-enzyme condensates, CLPX maximizes PLP-dependent delta-transamination and rescues malformed nascent peptides. Overall, their actions occur in granules with multivalent or hydrophobic interactions, separated from the aqueous phase. Thus, the role of CLPXP in the matrix is compartment-selective, as other mitochondrial peptidases: MPPs at precursor import pores, m-AAA and i-AAA at either IMM face, PARL within the IMM, and OMA1/HTRA2 in the intermembrane space.
Topics: Endopeptidase Clp; Animals; Mice; Mitochondria; Mitochondrial Proteins; Mice, Knockout; Heme; Protein Biosynthesis; Humans; Mitochondrial Membranes; Stress, Physiological
PubMed: 38927630
DOI: 10.3390/genes15060694 -
NPJ Parkinson's Disease Jun 2024Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by mitochondrial dysfunction and accumulation of alpha-synuclein (α-Syn)-containing...
Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by mitochondrial dysfunction and accumulation of alpha-synuclein (α-Syn)-containing protein aggregates known as Lewy bodies (LB). Here, we investigated the entry of α-Syn into mitochondria to cause mitochondrial dysfunction and loss of cellular fitness in vivo. We show that α-Syn expressed in yeast and human cells is constitutively imported into mitochondria. In a transgenic mouse model, the level of endogenous α-Syn accumulation in mitochondria of dopaminergic neurons and microglia increases with age. The imported α-Syn is degraded by conserved mitochondrial proteases, most notably NLN and PITRM1 (Prd1 and Cym1 in yeast, respectively). α-Syn in the mitochondrial matrix that is not degraded interacts with respiratory chain complexes, leading to loss of mitochondrial DNA (mtDNA), mitochondrial membrane potential and cellular fitness decline. Importantly, enhancing mitochondrial proteolysis by increasing levels of specific proteases alleviated these defects in yeast, human cells, and a PD model of mouse primary neurons. Together, our results provide a direct link between α-synuclein-mediated cellular toxicity and its import into mitochondria and reveal potential therapeutic targets for the treatment of α-synucleinopathies.
PubMed: 38906862
DOI: 10.1038/s41531-024-00733-y -
Medicine Jun 2024The present study utilizes network pharmacology and molecular docking methodologies to investigate the mechanism of action behind the intervention of Polygonum capitatum...
The present study utilizes network pharmacology and molecular docking methodologies to investigate the mechanism of action behind the intervention of Polygonum capitatum Buch.-Ham.ex D. Don (THL) in treating pulmonary nodules (PN). This research aims to provide a theoretical foundation for broadening the clinical application of THL. Active components of THL were identified and screened through an extensive literature review and the PharmMapper database, followed by an analysis of their target interactions. Relevant targets associated with PN were selected using databases such as OMIM and GeneCards, with an intersection of the two sets being determined. STRING11.5 facilitated the acquisition of protein-protein interaction data, which was then imported into Cytoscape 3.7.2 to establish a protein interaction network topology. This enabled the identification of pivotal targets affected by THL intervention in PN. The study further employed the Metascape database to conduct GO and KEGG bioinformatics enrichment analyses, which illuminated core pathways involved in THL's therapeutic effects on PN. A comprehensive component-target-pathway diagram was constructed utilizing Cytoscape 3.7.2 software, with molecular docking validations carried out via Maestro software. A total of 49 active THL ingredients were discerned, implicating 67 PN-relevant targets. Subsequent software analysis pinpointed 10 key targets, including ALB, EGFR, and SRC. Molecular docking studies indicated strong binding affinities for most protein-compound pairs, with 44 out of 60 docking results exhibiting binding energies below -5 kcal/mol. Enrichment analysis highlights that key targets are mainly involved in pathways such as cancer, lipid metabolism and atherosclerosis, estrogen signaling, IL-17 signaling, complement and coagulation cascades, and chemical carcinogenesis through receptor activation. Through comprehensive network pharmacological approaches, this research delineates the synergy of THL's multiple components, targets, and pathways in mitigating PN. It posits that primary active ingredients of THL - quercetin, salidroside, and oleanolic acid - may exert effects on targets like ALB, EGFR, SRC, potentially modulating pathways associated with cancer, lipid and atherosclerosis, and IL-17 signaling in the context of PN intervention.
Topics: Molecular Docking Simulation; Polygonum; Humans; Network Pharmacology; Protein Interaction Maps; Solitary Pulmonary Nodule; Drugs, Chinese Herbal
PubMed: 38905418
DOI: 10.1097/MD.0000000000038419 -
Plant Direct Jun 2024Chloroplasts play a vital role in plant growth and development, which are the main sites of photosynthesis and the production of hormones and metabolites. Despite their...
Chloroplasts play a vital role in plant growth and development, which are the main sites of photosynthesis and the production of hormones and metabolites. Despite their significance, the regulatory mechanisms governing chloroplast development remain unclear. In our investigation, we identified a rice mutant with defective chloroplasts in rice ( L.), named albino lethal 13 (), which displayed a distinct albino phenotype in leaves, ultimately resulting in seedling lethality. Molecular cloning revealed that encodes a novel rice protein with no homologous gene or known conserved domain. This gene was located in the chloroplast and exhibited constitutive expression in various tissues, particularly in green tissues and regions of active cell growth. Our study's findings reveal that RNAi-mediated knockdown of led to a pronounced albino phenotype, reduced chlorophyll and carotenoid contents, a vesicle chloroplast structure, and a decrease in the expression of chloroplast-associated genes. Consequently, the pollen fertility and seed setting rate were lower compared with the wild type. In contrast, the overexpression of resulted in an increased photosynthetic rate, a higher total grain number per panicle, and enhanced levels of indole-3-acetic acid (IAA) in the roots and gibberellin A3 (GA3) in the shoot. These outcomes provide new insights on the role of in regulating chloroplast development in rice.
PubMed: 38903415
DOI: 10.1002/pld3.610 -
Nature Communications Jun 2024Mitochondria require an extensive proteome to maintain a variety of metabolic reactions, and changes in cellular demand depend on rapid adaptation of the mitochondrial...
Mitochondria require an extensive proteome to maintain a variety of metabolic reactions, and changes in cellular demand depend on rapid adaptation of the mitochondrial protein composition. The TOM complex, the organellar entry gate for mitochondrial precursors in the outer membrane, is a target for cytosolic kinases to modulate protein influx. DYRK1A phosphorylation of the carrier import receptor TOM70 at Ser91 enables its efficient docking and thus transfer of precursor proteins to the TOM complex. Here, we probe TOM70 phosphorylation in molecular detail and find that TOM70 is not a CK2 target nor import receptor for MIC19 as previously suggested. Instead, we identify TOM20 as a MIC19 import receptor and show off-target inhibition of the DYRK1A-TOM70 axis with the clinically used CK2 inhibitor CX4945 which activates TOM20-dependent import pathways. Taken together, modulation of DYRK1A signalling adapts the central mitochondrial protein entry gate via synchronization of TOM70- and TOM20-dependent import pathways for metabolic rewiring. Thus, DYRK1A emerges as a cytosolic surveillance kinase to regulate and fine-tune mitochondrial protein biogenesis.
Topics: Dyrk Kinases; Protein-Tyrosine Kinases; Protein Serine-Threonine Kinases; Mitochondria; Mitochondrial Precursor Protein Import Complex Proteins; Signal Transduction; Humans; Mitochondrial Membrane Transport Proteins; Phosphorylation; Protein Transport; HEK293 Cells; HeLa Cells; Mitochondrial Proteins
PubMed: 38902238
DOI: 10.1038/s41467-024-49611-4 -
PloS One 2024Unravelling how energy metabolism and stress responses are regulated in human scalp hair follicles could reveal novel insights into the controls of hair growth and...
Unravelling how energy metabolism and stress responses are regulated in human scalp hair follicles could reveal novel insights into the controls of hair growth and provide new targets to manage hair loss disorders. The Mitochondrial Pyruvate Carrier (MPC) imports pyruvate, produced via glycolysis, into the mitochondria, fuelling the TCA cycle. Previous work has shown that MPC inhibition promotes lactate generation, which activates murine epithelial hair follicle stem cells (eHFSCs). However, by pharmacologically targeting the MPC in short-term human hair follicle ex vivo organ culture experiments using UK-5099, we induced metabolic stress-responsive proliferative arrest throughout the human hair follicle epithelium, including within Keratin 15+ eHFSCs. Through transcriptomics, MPC inhibition was shown to promote a gene expression signature indicative of disrupted FGF, IGF, TGFβ and WNT signalling, mitochondrial dysfunction, and activation of the integrated stress response (ISR), which can arrest cell cycle progression. The ISR, mediated by the transcription factor ATF4, is activated by stressors including amino acid deprivation and ER stress, consistent with MPC inhibition within our model. Using RNAScope, we confirmed the upregulation of both ATF4 and the highly upregulated ATF4-target gene ADM2 on human hair follicle tissue sections in situ. Moreover, treatment with the ISR inhibitor ISRIB attenuated both the upregulation of ADM2 and the proliferative block imposed via MPC inhibition. Together, this work reveals how the human hair follicle, as a complex and metabolically active human tissue system, can dynamically adapt to metabolic stress.
Topics: Humans; Hair Follicle; Activating Transcription Factor 4; Stress, Physiological; Cell Proliferation; Mitochondria
PubMed: 38900734
DOI: 10.1371/journal.pone.0303742 -
ELife Jun 2024Mitochondria are the cellular energy hub and central target of metabolic regulation. Mitochondria also facilitate proteostasis through pathways such as the 'mitochondria...
Mitochondria are the cellular energy hub and central target of metabolic regulation. Mitochondria also facilitate proteostasis through pathways such as the 'mitochondria as guardian in cytosol' (MAGIC) whereby cytosolic misfolded proteins (MPs) are imported into and degraded inside mitochondria. In this study, a genome-wide screen in uncovered that Snf1, the yeast AMP-activated protein kinase (AMPK), inhibits the import of MPs into mitochondria while promoting mitochondrial biogenesis under glucose starvation. We show that this inhibition requires a downstream transcription factor regulating mitochondrial gene expression and is likely to be conferred through substrate competition and mitochondrial import channel selectivity. We further show that Snf1/AMPK activation protects mitochondrial fitness in yeast and human cells under stress induced by MPs such as those associated with neurodegenerative diseases.
Topics: Saccharomyces cerevisiae; Mitochondria; Humans; Protein Transport; Protein Folding; Protein Serine-Threonine Kinases; Saccharomyces cerevisiae Proteins; Glucose
PubMed: 38900507
DOI: 10.7554/eLife.87518