Altered Profile Research Articles

Intestinal Dysbacteriosis Contributes to Persistent Cognitive Impairment after Resolution of Acute Liver Failure

Regulating the gut microbiota alleviates hepatic encephalopathy (HE). It remains unclear whether it is imperative to withhold treatment for microbial imbalance after liver functional recovery. The aim of this work was to elucidate the alterations in cognitive behavior, liver function, synaptic transmission, and brain metabolites in acute liver failure (ALF) mice before and after hepatic function recovery. In this study, thioacetamide was injected intraperitoneally to establish an ALF mouse model, which induced HE. By performing hierarchical clustering analysis, we showed that the liver functions normalized, but cognitive dysfunction and intestinal dysbacteriosis were found in the ALF mice 14 days after thioacetamide injection. In addition, fecal microbiota transplantation from the ALF mice with liver function recovery could induce liver injury and cognitive impairment. Moreover, alterations in synaptic transmission were found in the ALF mice with liver function improvement, and the correlations between the gut bacteria and synaptic transmission in the cortex were significant. Finally, we detected apparent alterations in the brain metabolic profiles of the ALF mice after liver function improvement by performing 1H nuclear magnetic resonance spectroscopy, suggesting a risk of HE. These results show that intestinal dysbacteriosis in ALF mice with liver function recovery is sufficient to induce liver injury and cognitive impairment. These results indicate that continuous care may be necessary for monitoring microbial imbalance even in patients with ALF-induced HE whose liver function has recovered significantly.

Dietary bile acids supplementation decreases hepatic fat deposition with the involvement of altered gut microbiota and liver bile acids profile in broiler chickens

BackgroundHigh-fat diets (HFD) are known to enhance feed conversion ratio in broiler chickens, yet they can also result in hepatic fat accumulation. Bile acids (BAs) and gut microbiota also play key roles in the formation of fatty liver. In this study, our objective was to elucidate the mechanisms through which BA supplementation reduces hepatic fat deposition in broiler chickens, with a focus on the involvement of gut microbiota and liver BA composition.ResultsNewly hatched broiler chickens were allocated to either a low-fat diet (LFD) or HFD, supplemented with or without BAs, and subsequently assessed their impacts on gut microbiota, hepatic lipid metabolism, and hepatic BA composition. Our findings showed that BA supplementation significantly reduced plasma and liver tissue triglyceride (TG) levels in 42-day-old broiler chickens (P < 0.05), concurrently with a significant decrease in the expression levels of fatty acid synthase (FAS) in liver tissue (P < 0.05). These results suggest that BA supplementation effectively diminishes hepatic fat deposition. Under the LFD, BAs supplementation increased the BA content and ratio of Non 12-OH BAs/12-OH BAs in the liver and increased the Akkermansia abundance in cecum. Under the HFD, BA supplementation decreased the BAs and increased the relative abundances of chenodeoxycholic acid (CDCA) and cholic acid (CA) in hepatic tissue, while the relative abundances of Bacteroides were dramatically reduced and the Bifidobacterium, Escherichia, and Lactobacillus were increased in cecum. Correlation analyses showed a significant positive correlation between the Akkermansia abundance and Non 12-OH BA content under the LFD, and presented a significant negative correlation between the Bacteroides abundance and CA or CDCA content under the HFD.ConclusionsThe results indicate that supplementation of BAs in both LFD and HFD may ameliorate hepatic fat deposition in broiler chickens with the involvement of differentiated microbiota–bile acid profile pathways.Graphical

Mitochondrial stress-induced H4K12 hyperacetylation dysregulates transcription in Parkinson's disease.

Aberrant epigenetic modification has been implicated in the pathogenesis of Parkinson's disease (PD), which is characterized by the irreversible loss of dopaminergic (DAergic) neurons. However, the mechanistic landscape of histone acetylation (ac) in PD has yet to be fully explored. Herein, we mapped the proteomic acetylation profiling changes at core histones H4 and thus identified H4K12ac as a key epigenomic mark in dopaminergic neuronal cells as well as in MitoPark animal model of PD. Notably, the significantly elevated H4K12ac deposition in post-mortem PD brains highlights its clinical relevance to human PD. Increased histone acetyltransferase (HAT) activity and decreased histone deacetylase 2 (HDAC2) and HDAC4 were found in experimental PD cell models, suggesting the HAT/HDAC imbalance associated with mitochondrial stress. Following our delineation of the proteasome dysfunction that possibly contributes to H4K12ac deposition, we characterized the altered transcriptional profile and disease-associated pathways in the MitoPark mouse model of PD. Our study uncovers the axis of mitochondrial impairment-H4K12ac deposition-altered transcription/disease pathways as a neuroepigenetic mechanism underlying PD pathogenesis. These findings provide mechanistic information for the development of potential pharmacoepigenomic translational strategies for PD.

A worldwide study of white matter microstructural alterations in people living with Parkinson’s disease

The progression of Parkinson’s disease (PD) is associated with microstructural alterations in neural pathways, contributing to both motor and cognitive decline. However, conflicting findings have emerged due to the use of heterogeneous methods in small studies. Here we performed a large diffusion MRI study in PD, integrating data from 17 cohorts worldwide, to identify stage-specific profiles of white matter differences. Diffusion-weighted MRI data from 1654 participants diagnosed with PD (age: 20–89 years; 33% female) and 885 controls (age: 19–84 years; 47% female) were analyzed using the ENIGMA-DTI protocol to evaluate white matter microstructure. Skeletonized maps of fractional anisotropy (FA) and mean diffusivity (MD) were compared across Hoehn and Yahr (HY) disease groups and controls to reveal the profile of white matter alterations at different stages. We found an enhanced, more widespread pattern of microstructural alterations with each stage of PD, with eventually lower FA and higher MD in almost all regions of interest: Cohen’s d effect sizes reached d = −1.01 for FA differences in the fornix at PD HY Stage 4/5. The early PD signature in HY stage 1 included higher FA and lower MD across the entire white matter skeleton, in a direction opposite to that typical of other neurodegenerative diseases. FA and MD were associated with motor and non-motor clinical dysfunction. While overridden by degenerative changes in the later stages of PD, early PD is associated with paradoxically higher FA and lower MD in PD, consistent with early compensatory changes associated with the disorder.

Transcription Factors Sox8 and Sox10 Contribute with Different Importance to the Maintenance of Mature Oligodendrocytes.

Myelin-forming oligodendrocytes in the vertebrate nervous system co-express the transcription factor Sox10 and its paralog Sox8. While Sox10 plays crucial roles throughout all stages of oligodendrocyte development, including terminal differentiation, the loss of Sox8 results in only mild and transient perturbations. Here, we aimed to elucidate the roles and interrelationships of these transcription factors in fully differentiated oligodendrocytes and myelin maintenance in adults. For that purpose, we conducted targeted deletions of Sox10, Sox8, or both in the brains of two-month-old mice. Three weeks post-deletion, none of the resulting mouse mutants exhibited significant alterations in oligodendrocyte numbers, myelin sheath counts, myelin ultrastructure, or myelin protein levels in the corpus callosum, despite efficient gene inactivation. However, differences were observed in the myelin gene expression in mice with Sox10 or combined Sox8/Sox10 deletion. RNA-sequencing analysis on dissected corpus callosum confirmed substantial alterations in the oligodendrocyte expression profile in mice with combined deletion and more subtle changes in mice with Sox10 deletion alone. Notably, Sox8 deletion did not affect any aspects of the expression profile related to the differentiated state of oligodendrocytes or myelin integrity. These findings extend our understanding of the roles of Sox8 and Sox10 in oligodendrocytes into adulthood and have important implications for the functional relationship between the paralogs and the underlying molecular mechanisms.

Unlocking lager's flavour palette by metabolic engineering of Saccharomyces pastorianus for enhanced ethyl ester production

Despite being present in trace amounts, ethyl esters play a crucial role as flavour compounds in lager beer. In yeast, ethyl hexanoate, ethyl octanoate and ethyl decanoate, responsible for fruity and floral taste tones, are synthesized from the toxic medium chain acyl-CoA intermediates released by the fatty acid synthase complex during the fatty acid biosynthesis, as a protective mechanism. The aim of this study was to enhance the production of ethyl esters in the hybrid lager brewing yeast Saccharomyces pastorianus by improving the medium chain acyl-CoA precursor supply. Through CRISPR-Cas9-based genetic engineering, specific FAS1 and FAS2 genes harbouring mutations in domains of the fatty acid synthesis complex were overexpressed in a single and combinatorial approach. These mutations in the ScFAS genes led to specific overproduction of the respective ethyl esters: overexpression of ScFAS1I306A and ScFAS2G1250S significantly improved ethyl hexanoate production and ScFAS1R1834K boosted the ethyl octanoate production. Combinations of ScFAS1 mutant genes with ScFAS2G1250S greatly enhanced predictably the final ethyl ester concentrations in cultures grown on full malt wort, but also resulted in increased levels of free medium chain fatty acids causing alterations in flavour profiles. Finally, the elevated medium chain fatty acid pool was directed towards the ethyl esters by overexpressing the esterase ScEEB1. The genetically modified S. pastorianus strains were utilized in lager beer production, and the resulting beverage exhibited significantly altered flavour profiles, thereby greatly expanding the possibilities of the flavour palette of lager beers.

Multimodal analysis of methylation and fragmentomic profiles in plasma cell free DNA for differentiation of benign and malignant breast tumors.

7 Background: Breast cancer ranks as the second leading cause of cancer-related mortality among women globally. Early detection of breast cancer is crucial for improving patient outcomes and reducing mortality rates. Liquid biopsy, which relies on circulating tumor DNA (ctDNA) shed by breast tumors into the bloodstream, presents a promising non-invasive approach for early breast cancer detection. However, accurately distinguishing between benign breast abnormalities and malignant tumors remains a significant clinical challenge, as misdiagnosis can lead to unnecessary invasive procedures. Methods: Herein, we employed a multimodal analysis approach, namely SPOT-MAS (Screen for the Presence of Tumor by DNA Methylation and Size), to profile alterations in methylation and fragment length patterns of cell-free DNA (cfDNA) from 169 breast cancer-confirmed patients and 99 patients diagnosed with benign breast lumps including cysts, fibroadenomas, and fibrocystic changes. A robust machine learning model was constructed using these signatures to differentiate between breast cancer patients and individuals with benign lesions. Results: Our genome-wide analyses identified distinct profiles of methylation changes, copy number alterations, and end motifs in cfDNA, enabling discrimination between breast cancer patients and individuals with benign conditions. Notably, we observed a significant enrichment of Thymine and Adenine at cfDNA cleavage sites in breast cancer patients. Moreover, our target sequencing analyses uncovered distinct methylation patterns in the regulatory regions of multiple genes, including hypermethylation in GPR126 or hypomethylation in TOP1 or MAFB in breast cancer cfDNA. Our multi-featured model achieved an AUC of 0.92 (95% CI: 0.88–0.97), a specificity of 97.44% and sensitivities of 57.14% and 61.70% for stage I and stage II–III patients, respectively. Furthermore, our multimodal assay effectively differentiated multiple molecular subtypes of breast tumors from benign lesions, achieving the highest sensitivity of 71.43% with Luminal A, followed by Luminal B, Triple Negative Breast Cancer (TNBC), Luminal B-HER2, and HER2 with sensitivities of 66.67%, 60%, 58.33% and 55.56%, respectively. Conclusions: Our findings demonstrate the potential of cancer-specific methylation and fragmentomic patterns in plasma cfDNA as novel biomarkers for accurately discriminating between breast cancer and benign lesions. This capability reduces the false-positive rate and helps avoid unnecessary biopsies in current clinical practice.

Genome editing-based mutagenesis stably modifies composition of wax esters synthesized by Euglena gracilis under anaerobic conditions

Microalgal oil production represents a promising renewable biofuel source. Metabolic engineering can enhance its utility, transforming it into an improved biofuel and expanding its applications as a feedstock for commodity chemicals, thereby increasing their value in biorefineries. This study focused on anaerobic wax ester production by the microalga Euglena gracilis, aiming to develop stable mutant strains with altered wax ester profiles through genome editing. Two enzymes in the fatty acid beta-oxidation pathway involved in wax ester production were targeted—3-ketoacyl-CoA thiolase and acyl-CoA dehydrogenase—using clustered regularly interspaced short palindromic repeats/Cas9. The results revealed one genetic mutation that lengthened and three that shortened the distribution of wax ester compositions compared to the wild-type (WT). The triple-knockout mutant, combining mutations that shorten wax ester chains, produced wax esters with acyl chains two carbons shorter than WT. This study established a methodology to stably modify wax ester composition in E. gracilis.

Binary classification of copy number alteration profiles in liquid biopsy with potential clinical impact in advanced NSCLC

Liquid biopsy has recently emerged as an important tool in clinical practice particularly for lung cancer patients. We retrospectively evaluated cell-free DNA analyses performed at our Institution by next generation sequencing methodology detecting the major classes of genetic alterations. Starting from the graphical representation of chromosomal alterations provided by the analysis software, we developed a support vector machine classifier to automatically classify chromosomal profiles as stable (SCP) or unstable (UCP). High concordance was found between our binary classification and tumor fraction evaluation performed using shallow whole genome sequencing. Among clinical features, UCP patients were more likely to have ≥ 3 metastatic sites and liver metastases. Longitudinal assessment of chromosomal profiles in 33 patients with lung cancer receiving immune checkpoint inhibitors (ICIs) showed that only patients that experienced early death or hyperprogressive disease retained or acquired an UCP within 3 weeks from the beginning of ICIs. UCP was not observed following ICIs among patients that experienced progressive disease or clinical benefit. In conclusion, our binary classification, applied to whole copy number alteration profiles, could be useful for clinical risk stratification during systemic treatment for non-small cell lung cancer patients.

Sex Differences in Hepatic Inflammation, Lipid Metabolism, and Mitochondrial Function Following Early Lipopolysaccharide Exposure in Epileptic WAG/Rij Rats.

Among the non-communicable neurological diseases, epilepsy is characterized by abnormal brain activity with several peripheral implications. The role of peripheral inflammation in the relationship between seizure development and nonalcoholic fatty liver disease based on sex difference remains still overlooked. Severe early-life infections lead to increased inflammation that can aggravate epilepsy and hepatic damage progression, both related to increased odds of hospitalization for epileptic patients with liver diseases. Here, we induced a post-natal-day 3 (PND3) infection by LPS (1 mg/kg, i.p.) to determine the hepatic damage in a genetic model of young epileptic WAG/Rij rats (PND45). We evaluated intra- and inter-gender differences in systemic and liver inflammation, hepatic lipid dysmetabolism, and oxidative damage related to mitochondrial functional impairment. First, epileptic rats exposed to LPS, regardless of gender, displayed increased serum hepatic enzymes and altered lipid profile. Endotoxin challenge triggered a more severe inflammatory and immune response in male epileptic rats, compared to females in both serum and liver, increasing pro-inflammatory cytokines and hepatic immune cell recruitment. Conversely, LPS-treated female rats showed significant alterations in systemic and hepatic lipid profiles and reduced mitochondrial fatty acid oxidation. The two different sex-dependent mechanisms of LPS-induced liver injury converge in increased ROS production and related mitochondrial oxidative damage in both sexes. Notably, a compensatory increase in antioxidant defense was evidenced only in female rats. Our study with a translational potential demonstrates, for the first time, that early post-natal infections in epileptic rats induced or worsened hepatic disorders in a sex-dependent manner, amplifying inflammation, lipid dysmetabolism, and mitochondrial impairment.

Unravelling tRNA fragments in DENV pathogenesis: Insights from RNA sequencing

Small non-coding RNAs (sncRNAs) derived from tRNAs are known as tRNA-derived small RNAs (tsRNAs). These tsRNAs are further categorized into tRNA-derived fragments (tRFs) and tRNA halves (tiRNAs), which play significant roles in the various molecular mechanisms underlying certain human diseases. However, the generation of tsRNAs and their potential roles during Dengue virus (DENV) infection is not yet known. Here, we performed small RNA sequencing to identify the generation and alterations in tsRNAs expression profiles of DENV-infected Huh7 cells. Upon DENV infection, tRNA fragmentation was found to be increased. We identified a significant number of differentially expressed tsRNAs during DENV infection. Interestingly, the 3′tRF population showed upregulation, while the i-tRF population exhibited downregulation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was performed to analyze the impact of differentially expressed tsRNAs on DENV pathogenesis. Our results suggest that differentially expressed tsRNAs are involved in transcriptional regulation via RNA polymerase II promoter and metabolic pathways. Overall, our study contributes significantly to our understanding of the roles played by tsRNAs in the complex dynamics of DENV infection.

Comparative Proteomic Study of Retinal Ganglion Cells Undergoing Various Types of Cellular Stressors.

Retinal ganglion cell (RGC) damage serves as a key indicator of various retinal degenerative diseases, including diabetic retinopathy (DR), glaucoma, retinal arterial and retinal vein occlusions, as well as inflammatory and traumatic optic neuropathies. Despite the growing body of data on the RGC proteomics associated with these conditions, there has been no dedicated study conducted to compare the molecular signaling pathways involved in the mechanism of neuronal cell death. Therefore, we launched the study using two different insults leading to RGC death: glutamate excitotoxicity and optic nerve crush (ONC). C57BL/6 mice were used for the study and underwent NMDA- and ONC-induced damage. Twenty-four hours after ONC and 1 hour after NMDA injection, we collected RGCs using CD90.2 coupled magnetic beads, prepared protein extracts, and employed LC-MS for the global proteomic analysis of RGCs. Statistically significant changes in proteins were analyzed to identify changes to cellular signaling resulting from the treatment. We identified unique and common alterations in protein profiles in RGCs undergoing different types of cellular stresses. Our study not only identified both unique and shared proteomic changes but also laid the groundwork for the future development of a therapeutic platform for testing gene candidates for DR and glaucoma.

Chloroplastic ascorbate modifies plant metabolism and may act as a metabolite signal regardless of oxidative stress.

Ascorbate is a major plant metabolite that plays crucial roles in various processes, from reactive oxygen scavenging to epigenetic regulation. However, to what extent and how ascorbate modulates metabolism is largely unknown. We investigated the consequences of chloroplastic and total cellular ascorbate-deficiencies by studying chloroplastic ascorbate-transporter mutant lines lacking PHOSPHATE TRANSPORTER 4; 4 (PHT4; 4) , and the ascorbate-deficient vtc2-4 mutant of Arabidopsis (Arabidopsis thaliana). Under regular growth conditions, both ascorbate deficiencies caused minor alterations in photosynthesis, with no apparent signs of oxidative damage. In contrast, metabolomics analysis revealed global and largely overlapping alterations in the metabolome profiles of both ascorbate-deficiency mutants, suggesting that chloroplastic ascorbate modulates plant metabolism. We observed significant alterations in amino acid metabolism, particularly in arginine metabolism, activation of nucleotide salvage pathways, and changes in secondary metabolism. In addition, proteome-wide analysis of thermostability revealed that ascorbate may interact with enzymes involved in arginine metabolism, the Calvin-Benson cycle, and several photosynthetic electron transport components. Overall, our results suggest that, independently of oxidative stress, chloroplastic ascorbate modulates the activity of diverse metabolic pathways in vascular plants and may act as an internal metabolic signal.

Integrative analysis of single-Cell RNA sequencing and experimental validation in the study of abdominal aortic aneurysm progression

BackgroundAbdominal aortic aneurysm (AAA) is a complex vascular disorder characterized by the progressive dilation of the abdominal aorta, with a high risk of rupture and mortality.Understanding the cellular interactions and molecular mechanisms underlying AAA development is critical for identifying potential therapeutic targets. MethodsThis study utilized datasets GSE197748, GSE164678 and GSE183464 from the GEO database, encompassing bulk and single-cell RNA sequencing data from AAA and control samples. We performed principal component analysis, differential expression analysis, and functional enrichment analysis to identify key pathways involved in AAA. Cell-cell interactions were investigated using CellPhoneDB, focusing on fibroblasts, vascular smooth muscle cells (VSMCs), and macrophages. We further validated our findings using a mouse model of AAA induced by porcine pancreatic enzyme infusion, followed by gene expression analysis and co-immunoprecipitation experiments. ResultsOur analysis revealed significant alterations in gene expression profiles between AAA and control samples, with a pronounced immune response and cell adhesion pathways being implicated. Single-cell RNA sequencing data highlighted an increased proportion of pro-inflammatory macrophages, along with changes in the composition of fibroblasts and VSMCs in AAA. CellPhoneDB analysis identified critical ligand-receptor interactions, notably collagen type I alpha 1 chain (COL1A1)/COL1A2-CD18 and thrombospondin 1 (THBS1)-CD3, suggesting complex communication networks between fibroblasts and VSMCs. In vivo experiments confirmed the upregulation of these genes in AAA mice and demonstrated the functional interaction between COL1A1/COL1A2 and CD18. ConclusionThe interaction between fibroblasts and VSMCs, mediated by specific ligand-receptor pairs such as COL1A1/COL1A2-CD18 and THBS1-CD3, plays a pivotal role in AAA pathogenesis.

Physicochemical and structural insights into lyophilized mRNA-LNP from lyoprotectant and buffer screenings

The surge in RNA therapeutics has revolutionized treatments for infectious diseases like COVID-19 and shows the potential to expand into other therapeutic areas. However, the typical requirement for ultra-cold storage of mRNA-LNP formulations poses significant logistical challenges for global distribution. Lyophilization serves as a potential strategy to extend mRNA-LNP stability while eliminating the need for ultra-cold supply chain logistics. Although recent advancements have demonstrated the promise of lyophilization, the choice of lyoprotectant is predominately focused on sucrose, and there remains a gap in comprehensive evaluation and comparison of lyoprotectants and buffers. Here, we aim to systematically investigate the impact of a diverse range of excipients including oligosaccharides, polymers, amino acids, and various buffers, on the quality and performance of lyophilized mRNA-LNPs. From the screening of 45 mRNA-LNP formulations under various lyoprotectant and buffer conditions for lyophilization, we identified previously unexplored formulation compositions, e.g., polyvinylpyrrolidone (PVP) in Tris or acetate buffers, as promising alternatives to the commonly used oligosaccharides to maintain the physicochemical stability of lyophilized mRNA-LNPs. Further, we delved into how physicochemical and structural properties influence the functionality of lyophilized mRNA-LNPs. Leveraging high-throughput small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (cryo-TEM), we showed that there is complex interplay between mRNA-LNP structural features and cellular translation efficacy. We also assessed innate immune responses of the screened mRNA-LNPs in human peripheral blood mononuclear cells (PBMCs), and showed minimal alterations of cytokine secretion profiles induced by lyophilized formulations. Our results provide valuable insights into the structure-activity relationship of lyophilized formulations of mRNA-LNP therapeutics, paving the way for rational design of these formulations. This work creates a foundation for a comprehensive understanding of mRNA-LNP properties and in vitro performance change resulting from lyophilization.

Asprosin-induced alterations in female rat puberty and reproductive hormonal profiles

Objective To investigate the comprehensive effects of daily chronic asprosin administration on various pubertal and reproductive parameters in female rats. This study aims to elucidate the role of asprosin in regulating the onset of puberty and its influence on hormonal profiles and ovarian histology. Methods Asprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg daily for eight weeks. Hormonal assays and histological analyses were performed to evaluate the effects of asprosin on the onset of puberty and reproductive function. Results Daily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays revealed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights. Conclusions Role of adipokines in regulating puberty and reproductive function has increasingly gained recognition. This study aimed to provide the first comprehensive examination of the effects of daily chronic asprosin administration on pubertal and reproductive parameters in female rats. Utilising hormonal assays and histological analyses, asprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg, daily, for eight weeks. Our findings revealed that daily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays showed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights. These results provide new insights into asprosin’s role in advancing the age of first oestrus and modulating hormonal profiles, thereby offering potential benefits to the female reproductive system.

Propionic Acidemia, Methylmalonic Acidemia, and Cobalamin C Deficiency: Comparison of Untargeted Metabolomic Profiles.

Methylmalonic acidemia (MMA), propionic acidemia (PA), and cobalamin C deficiency (cblC) share a defect in propionic acid metabolism. In addition, cblC is also involved in the process of homocysteine remethylation. These three diseases produce various phenotypes and complex downstream metabolic effects. In this study, we used an untargeted metabolomics approach to investigate the biochemical differences and the possible connections among the pathophysiology of each disease. The significantly changed metabolites in the untargeted urine metabolomic profiles of 21 patients (seven MMA, seven PA, seven cblC) were identified through statistical analysis (p < 0.05; log2FC > |1|) and then used for annotation. Annotated features were associated with different metabolic pathways potentially involved in the disease's development. Comparative statistics showed markedly different metabolomic profiles between MMA, PA, and cblC, highlighting the characteristic species for each disease. The most affected pathways were related to the metabolism of organic acids (all diseases), amino acids (all diseases), and glycine and its conjugates (in PA); the transsulfuration pathway; oxidative processes; and neurosteroid hormones (in cblC). The untargeted metabolomics study highlighted the presence of significant differences between the three diseases, pointing to the most relevant contrast in the cblC profile compared to MMA and PA. Some new biomarkers were proposed for PA, while novel data regarding the alterations of steroid hormone profiles and biomarkers of oxidative stress were obtained for cblC disease. The elevation of neurosteroids in cblC may indicate a potential connection with the development of ocular and neuronal deterioration.

Unraveling molecular mechanistic disparities in pathogenic visceral Leishmania resistance between reptiles and mammals through comparative transcriptomic analyses

Leishmaniasis is one of the most important neglected tropical parasitic diseases, manifesting various clinical forms depending on the parasite species and the genetic background of the host. In order to elucidate the underlying mechanisms of reptilian defense against pathogenic Leishmania species and to delineate the global gene expression profile alterations during host-pathogen interaction, we established experimental animal and cell models using both heterothermic lizards (Phrynocephalus przewalskii) and homothermic mammals (BALB/c mice) infected with pathogenic Leishmania infantum (high virulence HCZ strain) and Leishmania donovani (low virulence 801 strain). Overall, the lizards didn't show any obvious clinical symptoms or immune responses in vivo. Using RNA-seq methodology, differentially expressed genes identified in the HCZ and 801-comparison groups of P. przewalskii were primarily associated with arginine biosynthesis, the MAPK signaling pathway and the PI3K-Akt signaling pathway. In contrast, higher parasite loads, exacerbated hepatic inflammatory lesions and enhanced immune responses were observed in BALB/c mice, with DEGs predominantly associated with immunological diseases, innate and adaptive immune responses. By integrating transcriptional data from reptile and mammalian hosts, we elucidated the pivotal role of amino acid metabolism and lipid metabolism in parasite control. In contrast to findings from animal experiments, Leishmania parasites effectively infected peritoneal macrophages of lizards in vitro, demonstrating a high infection rate. Furthermore, we used RT-qPCR to detect changes in cytokine expression in macrophages and found that Th1-type cytokines were significantly upregulated in lizards, facilitating the clearance of the HCZ strain 24 hours post-infection. Conversely, cytokine expression was generally suppressed in BALB/c mice, allowing immune evasion by the parasites.

Impact of prenatal THC exposure on lipid metabolism and microbiota composition in rat offspring

ObjectiveRecent studies have demonstrated that prenatal exposure to the psychoactive ingredient of cannabis that is tetrahydrocannabinol (THC) disrupts fatty acid (FA) signaling pathways in the developing brain, potentially linking to psychopathologic consequences. Our research aims to investigate whether changes in midbrain FA metabolism are linked to modifications in peripheral metabolism of FAs and shifts in microbiota composition. MethodsIn order to model prenatal exposure to THC (PTE) in rats, Sprague Dawley dams were systemically administered with THC (2 mg/kg, s.c.) or vehicle once daily from gestational day 5–20. To evaluate the metabolic impact of PTE in the offspring during preadolescence (postnatal day, PND, 25–28), we analyzed FA profiles and their bioactive metabolites in liver and midbrain tissues, and microbiota alterations. ResultsOur findings indicate that PTE leads to sex-specific metabolic changes. In both sexes, PTE resulted in increased liver de novo lipogenesis (DNL) and alterations in FA profiles, as well as changes in N-acylethanolamines (NAEs), ligands of peroxisome proliferator-activated receptor alpha (PPAR-α). In females only, PTE influenced gene expression of PPAR-α and fibroblast growth factor 21 (Fgf21). In male offspring only, PTE was associated with significantly reduced fasting glycaemia and with alterations in the levels of midbrain NAEs. Our analysis of the progeny gut microbiota revealed sex-dependent effects of PTE, notably an increased abundance of Ileibacterium in PTE-exposed male offspring, a change previously associated with the long-term effects of a maternal unbalanced diet. ConclusionsOur data suggest that in male PTE offspring a reduced fasting glycaemia, resulting from increased liver DNL and the absence of a compensatory effect by Ppar-α and FGF21 on glycemic homeostasis, are associated to alterations in midbrain NAEs ligands of PPAR-α. These metabolic changes within the midbrain, along with Ileibacterium abundance, may partly elucidate the heightened susceptibility to psychopathologic conditions previously observed in male offspring following PTE.

New insights into the function and mechanisms of piRNA PMLCPIR in promoting PM2.5-induced lung cancer

IntroductionExtensive studies have established the correlation between long-term PM2.5 exposure and lung cancer, yet the mechanisms underlying this association remain poorly understood. PIWI-interacting RNAs (piRNAs), a novel category of small non-coding RNAs, serve important roles in various diseases. However, their biological function and mechanism in PM2.5-induced lung cancer have not been thoroughly investigated. ObjectivesWe aimed to explore the oncogenic role of piRNA in lung cancer induced by PM2.5 exposure, as well as the underlying mechanisms. MethodsWe conducted a PM2.5-induced human lung epithelial cell malignant transformation model. Human samples were used to further verify the finding. In vitro proliferation, migration, and invasion assays were performed to study the function of piRNA. RNA-sequencing was used to elucidate the the mechanisms of how piRNA mediates cell functions. PiRNA pull-down and computational docking analysis were conducted to identify proteins that binding to piRNA. In vivo experiments were used to explore whether inhibition of PMLCPIR could have a therapeutic effect on lung cancer. ResultsWe identified a new up-regulated piRNA, termed PM2.5-induced lung cancer up-regulation piRNA (PMLCPIR), which promotes the proliferation of PM2.5-transformed cells and lung cancer cells. RNA sequencing revealed ITGB1 as a downstream target of PMLCPIR. Importantly, PMLCPIR binds to nucleolin (NCL) and increases the expression of its target gene, ITGB1, thereby activating PI3K/AKT signaling. The inhibition of PMLCPIR could promote apoptosis in lung cancer cells and enhance their chemosensitivity to anti-tumor drugs. ConclusionWe systematically identified the alterations of piRNA expression profiles in the PM2.5-induced malignant transformation model. Then, PMLCPIR was recognized as a novel oncogenic piRNA in PM2.5-induced lung cancer. Mechanically, PMLCPIR binds to NCL, enhancing ITGB1 expression and activating the ontogenetic PI3K/AKT signaling, potentially contributing to lung cancer progression. This study provides novel insights into the revelation of a new epigenetic regulator in PM2.5-induced lung cancer.