PubMed
Proteomic and metabolomic insights into the mechanisms of calcium-mediated salt stress tolerance in hemp
Plant Mol Biol. 2024 Nov 18;114(6):126. doi: 10.1007/s11103-024-01525-x.ABSTRACTIndustrial hemp (Cannabis sativa L.) is a multifaced crop that has the potential to be exploited for many industrial applications, and making use of salt lands is considered to be a sustainable development strategy for the hemp industry. However, no elite salt-tolerant hemp varieties have been developed, and therefore supplementing appropriate exogenous substances to saline soil is one possible solution. Calcium-containing compounds are well-known for their salt tolerance enhancing effects, but the underlying molecular mechanisms remain largely unclear. Here, we first assessed the ameliorative effects of calcium amendments on salt-stressed hemp plants and then investigated these mechanisms on hemp using integrative analysis of proteomics and metabolomics. The stress phenotypes could be lessened by Ca2+ treatment. Certain concentrations of Ca2+ maintained relative electrical conductivity and the contents of malondialdehyde and chlorophyll. Ca2+ treatment also generally led to greater accumulations of soluble proteins, soluble carbohydrates and proline, and enhanced the activities of superoxide dismutase and peroxidase. Through functional classification, pathway enrichment, and network analysis, our data reveal that accumulation of dipeptides is a prominent metabolic signature upon exogenous Ca2+ treatment, and that changes in mitochondrial properties may play an important role in enhancing the salt tolerance. Our results outline the complex metabolic alternations involved in calcium-mediated salt stress resistance, and these data and analyses would be useful for future functional studies.PMID:39557670 | DOI:10.1007/s11103-024-01525-x
Tailored Metal-Organic Framework-Based Nanozymes for Enhanced Enzyme-Like Catalysis
Angew Chem Int Ed Engl. 2024 Nov 18:e202420200. doi: 10.1002/anie.202420200. Online ahead of print.ABSTRACTThe global crisis of bacterial infections is exacerbated by the escalating threat of microbial antibiotic resistance. Nanozymes promise to provide ingenious solutions. Here, we reported a homogeneous catalytic structure of Pt nanoclusters with finely tuned metal-organic framework (ZIF-8) channel structures for the treatment of infected wounds. Catalytic site normalization showed that the active site of the Pt aggregates structure with fine-tuned pore modifications structure had a catalytic capacity of 14.903 ×105 min-1, which was 18.7 times higher than that of the Pt particles in monodisperse state in ZIF-8 (0.793 ×105 min-1). In situ tests revealed that the change from homocleavage to heterocleavage of hydrogen peroxide at the interface of the nanozyme was one of the key reasons for the improvement of nanozyme activity. Density-functional theory and kinetic simulations of the reaction interface jointly determine the role of the catalytic center and the substrate channel together. Metabolomics analysis showed that the developed nanozyme, working in conjunction with reactive oxygen species, could effectively block energy metabolic pathways within bacteria, leading to spontaneous apoptosis and bacterial rupture. This pioneering study elucidates new ideas for the regulation of artificial enzyme activity and provides new perspectives for the development of efficient antibiotic substitutes.PMID:39557613 | DOI:10.1002/anie.202420200
Effect of "Xingshen-Jieyu" electroacupuncture on serum differential metabolites in patients with depression based on metabolomics
Zhen Ci Yan Jiu. 2024 Nov 25;49(11):1181-1189. doi: 10.13702/j.1000-0607.20240331.ABSTRACTOBJECTIVES: To explore the effect of "Xingshen-Jieyu" (inducing resuscitation and dispel ling melancholy) electroacupuncture (EA) on serum metabolites in patients with depression and its underlying mechanisms through serum non-targeted metabolomics.METHODS: Fifteen depression patients were subjected into the EA group, and 15 healthy volunteers were matched into the healthy group. EA (2 Hz/15 Hz, a tolerable strength) was applied to Baihui (GV20), Shenting (GV24), Toulinqi (GB15), Benshen (GB13), Touwei (ST8), Xuanli (GB6) and Qubin (GB7) for 30 min, 3 times a week for 6 weeks. The severity of depression was assessed using Hamilton Depression Scale-17 (HAMD-17) and Hamilton Anxiety Scale (HAMA), the degree of fatigue was evaluated using Fatigue Scale-14 (FS-14). The subjects sleep quality was assessed using Pittsburgh sleep quality index (PSQI). Blood samples were collected before and after the treatment for processing serum to perform non-targeted metabolomics profile detection using ultra-high-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), and Partial Least Squares Discriminant Analysis (PLS-DA, a statistical approach). Differential metabolites were screened and pathway enrichment analysis was performed.RESULTS: After the treatment, the scores of HAMD-17, HAMA, PSQI and FS-14 of depression patients were significantly lowered in the EA group (P<0.05). Compared with the healthy subjects, 46 differential metabolites (21 up-regulated, 25 down-regulated) were screened in patients with depression. Compared with pre-treatment in the EA group, 19 differential (17 up-regulated, and 2 down-regulated) metabolites were screened. Four down-regulated metabolites of the 46 differential metabolites in depression patients were recovered after EA treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of differential metabolites before and after EA showed that 19 metabolic pathways were enriched, mainly involving glutaminergic synapses, GABAergic synapses and several amino acid metabolism related pathways.CONCLUSIONS: "Xingshen-Jieyu" EA mainly regulates the metabolism of amino acids, and activities of neurotransmitter glutamate and GABA, and restores the excitatory/inhibitory balance, thus playing a role in improving depression.PMID:39557435 | DOI:10.13702/j.1000-0607.20240331
Integrated workflows using metabolomics, genome mining, and biological evaluation reveal oxepine-sulfur-containing anti-cryptococcal diketopiperazine produced by the endophyte Penicillium setosum
Fitoterapia. 2024 Nov 16:106301. doi: 10.1016/j.fitote.2024.106301. Online ahead of print.ABSTRACTCryptococcosis is a fungal infection for which treatment relies on old antifungal agents usually leading to drawbacks such as high toxicity and mainly low efficiency since drug resistance of microorganisms is strongly widespread. The discovery of new antifungal agents is urgent and investigations about underexplored Natural Product (NP) can yield the necessary outcomes to guide the discovery of new prototypes to anti-cryptococcal molecules development. In this scenario, an integrated strategy involving metabolomic data analysis, biological assessement and genome mining of P. setosum CMLD 18, revealed the biosynthesis of bis(methyl-sulfanyl) oxepine-containing diketopiperazine derivative, the bisdethiobis(methylthio)acetylaranotine (1) by the endophyte. The molecule showed a minimum inhibitory concentration (MIC) value of 0.125 mM when tested against C. neoformans. Evidence about the corresponding biosynthetic gene cluster (BGC) responsible for the biosynthesis of (1) in P. setosum were found. Moreover, other putative analogues of (1) were also detected, suggesting this microorganism may represent an important source of likely anti-cryptococcal molecules to be further investigated.PMID:39557348 | DOI:10.1016/j.fitote.2024.106301
Impact of Imperata Cylindrica polysaccharide on liver lipid metabolism disorders caused by hyperuricemia
Int J Biol Macromol. 2024 Nov 16:137592. doi: 10.1016/j.ijbiomac.2024.137592. Online ahead of print.ABSTRACTElevated uric acid levels are associated with lipid metabolism disorders. The effects of Imperata cylindrica polysaccharide (ICPC-a) were explored using a hyperuricemia mouse model and a uric acid-induced HepG2 hepatocyte model. ICPC-a significantly improved total cholesterol, triglycerides, low-density lipoprotein levels, and hepatic lipid deposition in hyperuricemia mice. The liver/body weight ratio decreased, and markers of liver damage, inflammation, and dyslipidemia improved. Metabolomics analysis suggested that ICPC-a modulates lipid metabolism by influencing the glycerophospholipid pathway and the enzyme LPCAT3. Stable HepG2 cell lines with knocked-down LPCAT3 were constructed, and Western blot and RT-PCR were used to assess the impact of its knockdown on lipid metabolism under uric acid stimulation. In cells with reduced LPCAT3 expression, ICPC-a was still able to alleviate uric acid-induced lipid accumulation, though the effect was less pronounced compared to cells with normal LPCAT3 levels. However, the effectiveness was diminished compared to cells where LPCAT3 was not knocked down. These findings indicated that LPCAT3 was an important target through which ICPC-a regulated lipid metabolism disorders induced by hyperuricemia. These discoveries emphasized that ICPC-a, as a prebiotic, could modulate hepatic lipid accumulation and inflammation, contributing to the maintenance of hepatic lipid homeostasis.PMID:39557274 | DOI:10.1016/j.ijbiomac.2024.137592
Multi-omics analysis of the toxic effects on gill tissues of crucian carp (Carassius auratus) from chronic exposure to environmentally relevant concentrations of Di(2-ethylhexyl) phthalate (DEHP)
Sci Total Environ. 2024 Nov 16:177599. doi: 10.1016/j.scitotenv.2024.177599. Online ahead of print.ABSTRACTThe pervasive use of the plasticizer di(2-ethylhexyl) phthalate (DEHP) poses potential risks to global aquatic ecosystems. This study systematically evaluated the adverse effects of chronic exposure to environmentally relevant concentrations of DEHP on gill tissues of crucian carp, utilizing histological examination, metabolomic, and transcriptomic analysis. The results demonstrated that DEHP induced significant histopathological alterations in gill tissues, with significant enrichment observed in multiple pathways associated with amino acid, hormone, lipid, and xenobiotic metabolism. Metabonomics-transcriptomics analyses indicated that DEHP-induced significantly over-activation of cytochrome P450 1B1-like (p < 0.001) and cytochrome P450 3A30-like (p < 0.05) via the nuclear xenobiotic receptors pathway was a key factor contributing to the disruption of tryptophan metabolism and steroid hormone biosynthesis, as well as inducing circadian rhythm disruption. Moreover, circadian rhythm disruption further exacerbated the imbalance of cytochrome P450 (CYP450) enzyme system as well as linoleic acid, arachidonic acid, sphingolipid, and glycerophospholipid metabolism. Overall, the feedback regulation between the CYP450 enzyme system and circadian rhythms emerged as the primary mechanism underlying DEHP-induced metabolic and transcriptional disruptions, ultimately resulting in gill toxicity. This study not only enriched the toxic effects on aquatic organisms of chronic exposure to DEHP, but provided potential biomarkers for the environmental risk assessment of DEHP.PMID:39557172 | DOI:10.1016/j.scitotenv.2024.177599
Multi-omics joint analysis reveals the mechanism underlying Chinese herbal Yougui Pill in the treatment of knee osteoarthritis
J Ethnopharmacol. 2024 Nov 16:119098. doi: 10.1016/j.jep.2024.119098. Online ahead of print.ABSTRACTETHNOPHARMACOLOGICAL RELEVANCE: Yougui Pill (YGP), originating from Jingyue Quanshu, comprises 10 traditional Chinese medicines (TCMs). This classic prescription is renowned for its ability to tonify the kidney, warm the kidney, promote yang, warm the interior, and dispel cold. YGP has proven effective in treating degenerative knee arthritis, osteoporosis, delayed fracture healing, and other orthopedic conditions, making it a widely used clinical prescription for knee osteoarthritis (KOA).AIM OF THE STUDY: Although YGP is commonly used in clinical practice, its pharmacodynamic material basis and anti-arthritis mechanisms remain unclear. This study aims to comprehensively analyze the chemical constituents of YGP and elucidate its anti-arthritis mechanisms.MATERIALS AND METHODS: Ultra-high performance liquid chromatography coupled with electrospray ionization-triple quadrupole-linear ion trap mass spectrometry(ESI-Q TRAP-MS/MS) was used to identify the chemical constituents of YGP. The Hulth method was utilized to establish KOA rat model, and pathological examinations were performed to assess the anti-arthritis effects of YGP. Integrated metabolomics and transcriptomics analyses were conducted to explore the anti-arthritis mechanisms of YGP. Key targets were confirmed via immunohistochemistry.RESULTS: A total of 1,981 chemical components were identified in YGP, predominantly phenolic acids and flavonoids. Compared with the model group, 422 differentially expressed metabolites and 214 differentially expressed genes were identified, primarily involving the MAPK signaling pathway, FoxO signaling pathway, and PI3K-Akt pathway. YGP exerted an anti-osteoarthritis effect by inhibiting the excessive activation of the EGFR/ERT/FOS signaling pathway.CONCLUSIONS: TCM offers significant advantages in the treatment of KOA, addressing the shortcomings of current clinical medications. YGP displayed exceptional pharmacodynamic effects. This study elucidated its pharmacodynamic material basis and anti-osteoarthritis mechanisms, providing substantial support for its clinical application and the development of related drugs.PMID:39557105 | DOI:10.1016/j.jep.2024.119098
Iron fortification modifies the microbial community structure and metabolome of a model surface-ripened cheese
Int J Food Microbiol. 2024 Nov 14;427:110971. doi: 10.1016/j.ijfoodmicro.2024.110971. Online ahead of print.ABSTRACTIron is a vital micronutrient for nearly all microorganisms, serving as a co-factor in critical metabolic pathways. However, cheese is an iron-restricted environment. Furthermore, it has been demonstrated that iron represents a growth-limiting factor for many microorganisms involved in cheese ripening and that this element is central to many microbial interactions occurring in this ecosystem. This study explores the impact of iron fortification on the growth and activity of a reduced microbial community composed of nine strains representative of the microbial community of surface-ripened cheeses. Three different iron compounds (ferrous sulfate, ferric chloride, ferric citrate) were used at three different concentrations, i.e., 18, 36, and 72 μM, to fortify cheese curd after inoculation with the consortium. This treatment significantly enhanced the growth of certain cheese-ripening bacteria in curd, resulting in substantial changes in the volatilome and metabolome profiles. These observations were dose-dependent, with more pronounced effects detected with higher iron concentrations. No statistically significant difference was observed in the microbial composition based on the iron compounds used for fortification, but this factor had an impact on the volatilome and amino acids profile. These findings highlight the importance of iron availability for the behavior of cheese microbial communities. They also open novel perspectives on cheesemakers' use of iron fortification to control microbial growth and improve cheese quality.PMID:39557002 | DOI:10.1016/j.ijfoodmicro.2024.110971
l-Isoleucine-Derived Amide-hydrazide Compounds Evaluated as a Novel Potential Agricultural Fungicide
J Agric Food Chem. 2024 Nov 18. doi: 10.1021/acs.jafc.4c06630. Online ahead of print.ABSTRACTBuilding upon previous structure-activity relationships about the fungicidal amide and hydrazide lead structures, 24 novel amide-hydrazide compounds were designed and synthesized with L-isoleucine as the initial skeleton to explore the impact of substituents in the hydrazide bridge on the fungicidal activity. Among these compounds, A5 exhibited excellent and broad spectrum inhibitory activity, along with satisfactory in vivo protective efficiency against R. solani at concentrations of 200 and 50 μg·mL-1. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed that compound A5 induced significant morphological changes in the R. solani mycelium coupled with vacuole rupture and cytoplasmic inhomogeneity in cellular structures. Transcriptomic and metabolomic analyses indicated that, following A5 treatment, the differentially expressed genes and metabolites were significantly enriched in carbohydrate metabolism-related pathways as well as in lipid metabolism-associated pathways, including glycerophospholipid metabolism, steroid biosynthesis, arachidonic acid metabolism, and sphingolipid metabolism. Additionally, compound A5 demonstrated low toxicity to zebrafish, with survival rates of 100% and 60% at concentrations of 1 and 10 μg·mL-1, respectively, over a period of 7 days. The above results provide theoretical guidance for the development of novel green hydrazide fungicidal candidates.PMID:39556774 | DOI:10.1021/acs.jafc.4c06630
Metabolomics reveals soluble epoxide hydrolase as a therapeutic target for high-sucrose diet-mediated gut barrier dysfunction
Proc Natl Acad Sci U S A. 2024 Nov 26;121(48):e2409841121. doi: 10.1073/pnas.2409841121. Epub 2024 Nov 18.ABSTRACTHighsucrose diet (HSD) was reported as a causative factor for multiorgan injuries. The underlying mechanisms and therapeutic strategies remain largely uncharted. In the present study, by using a metabolomics approach, we identified the soluble epoxide hydrolase (sEH) as a therapeutic target for HSD-mediated gut barrier dysfunction. Specifically, 16-week feeding on an HSD caused gut barrier dysfunction, such as colon inflammation and tight junction impairment in a murine model. A metabolomics analysis of mouse colon tissue showed a decrease in the 5(6)-epoxyeicosatrienoic acid [5(6)-EET] level and an increase in soluble epoxide hydrolase, which is related to HSD-mediated injuries to the gut barrier. The mice treated with a chemical inhibitor of sEH and the mice with genetic intervention by intestinal-specific knockout of the sEH gene significantly attenuated HSD-caused intestinal injuries by reducing HSD-mediated colon inflammation and improving the impaired tight junction caused by an HSD. Further, in vitro studies showed that treatment with 5(6)-EET, but not its hydrolytic product 5,6-dihydroxyeicosatrienoic acid (5,6-DiHET), significantly ablated high sucrose-caused intestinal epithelial inflammation and impaired tight junction. Additionally, 5(6)-EET is anti-inflammatory and improves gut epithelial tight junction while 5,6-DiHET cannot do so. This study presents an underlying mechanism of and a therapeutic strategy for the gut barrier dysfunction caused by an HSD.PMID:39556751 | DOI:10.1073/pnas.2409841121
Carotenoid composition and sequestration in cassava (Manihot esculentum Crantz) roots
PLoS One. 2024 Nov 18;19(11):e0312517. doi: 10.1371/journal.pone.0312517. eCollection 2024.ABSTRACTCassava (Manihot esculentum Crantz) is a staple food source for many developing countries. Its edible roots are high in starch but lack micronutrients such as β-carotene. In the present study, analysis of pedigree breeding populations has led to the identification of cassava accessions with enhanced β-carotene contents up to 40 μg/g DW. This represents 0.2% of the Recommended Daily Allowance (RDA) for vitamin A. The β-branch of the carotenoid pathway predominates in cassava roots, with dominant levels of β-carotene followed by other minor epoxides of β-ring derived carotenoids. Metabolomic analysis revealed that steady state levels of intermediary metabolism were not altered by the formation of carotenoids, similar to starch and carbohydrate levels. Apocarotenoids appeared to be independent of their carotenoid precursors. Lipidomic analysis provided evidence of a significant positive correlation between carotenoid and lipid content, in particular plastid specific galactolipids. Proteomic analysis of isolated amyloplasts identified the majority of proteins associated with translation and carbohydrate/starch biosynthesis (e.g. glucose-1-phosphate adenylyltransferase). No carotenoid related proteins were detected even in the highest carotenoid containing lines. Carotenoids were associated with fractions typically annotated as plastoglobuli and plastid membranes (particularly the envelope). Proteomic analysis confirmed these structures apart from plastoglobuli, thus potentially amyloplast structures may not contain classical plastoglobuli structures.PMID:39556611 | DOI:10.1371/journal.pone.0312517
Integrative analysis of non12-hydroxylated bile acid revealed the suppressed molecular map of alternative pathway in nonalcoholic steatohepatitis mice
FASEB J. 2024 Nov 30;38(22):e70167. doi: 10.1096/fj.202401630R.ABSTRACTBile acids (BAs) are significantly altered in the liver and serum of patients with nonalcoholic steatohepatitis (NASH). However, the underlying mechanisms of these changes, particularly BA alternative pathways (BAP) responsible for non12-OH BAs, remain unclear. RNA-seq data were initially analyzed to reveal the changes of gene expression in NASH patients. Targeted metabolomics were conducted on plasma from NASH mice induced by high-fat or western diet with CCl4 for 10-24 weeks. Liver tissues were examined using proteomics, RT-qPCR, and western blotting. An integrated approach was then employed to analyze protein interactions and network correlations. Analysis of RNA-seq data revealed the inhibition of CYP7B1 in NASH patients, indicating the dysregulation of BAP. In NASH mouse models, dysregulation of BA circulation was observed by increased plasma total BA (TBA) levels and decreased liver TBA, with liver swelling and histopathological changes. Targeted metabolomics revealed suppressed levels of non12-OH BAs, which inversely correlated with increased liver injury markers. The reduced mRNA and protein expression of Fxr and upregulation of Lxr signaling in livers suggested the suppressed BAP was modulated by Fxr-Lxr signaling. Moreover, BAP interactions predominantly implicated multiple metabolism disruptions, involving 7 hub proteins (Hk1, Acadsb, Pklr, Insr, Ldlr, Cyp27a1, and Cyp7b1), offering promising therapeutic targets for NASH. We presented the metabolic and proteomic map of BAP and its regulatory network in NASH progression. Therapeutic targeting of BAP or its co-regulatory proteins holds promise for NASH treatment and metabolic syndrome management.PMID:39556333 | DOI:10.1096/fj.202401630R
<em>Brassica rapa</em> L. crude polysaccharide meditated synbiotic fermented whey beverage ameliorates hypobaric hypoxia induced intestinal damage
Food Funct. 2024 Nov 18. doi: 10.1039/d4fo04667f. Online ahead of print.ABSTRACTHypobaric hypoxia causes oxidative stress and inflammatory responses and disrupts the gut microbiome and metabolome. In this study, we developed a synbiotic fermented whey beverage, combining kefir and Brassica rapa L. crude polysaccharides, to explore its protective effects against high-altitude induced injury in mice. The beverage, formulated with 0.8% (w/v) polysaccharides and kefir inoculation, demonstrated robust fermentation parameters and antioxidative capacity. When applied to a hypobaric hypoxia mouse model, the synbiotic fermented whey significantly reduced oxidation and protected the intestinal barrier by lowering inflammation, protecting the intestinal structure, increasing goblet cell counts, and reducing apoptosis. It also modulated the gut microbiota, enriching beneficial taxa as Intestinimonas and Butyricicoccaceae, while reducing harmful ones like Marvinbryantia and Proteus, and enhancing short-chain fatty acid (SCFA) production. Notably, the beverage increased berberine and nicotinic acid levels, activating the adenosine monophosphate-activated protein kinase (AMPK) signalling pathway and influencing nicotinate and nicotinamide metabolites linked to the suppression of Marvinbryantia, thereby alleviating intestinal inflammation and barrier damage. These effects contributed to the alleviation of hypoxia-induced intestinal damage in mice. This study highlights the potential of synbiotics and whey fermentation in novel nutritional interventions in high altitude environments.PMID:39555987 | DOI:10.1039/d4fo04667f
Characteristic alterations of gut microbiota and serum metabolites in patients with chronic tinnitus: a multi-omics analysis
Microbiol Spectr. 2024 Nov 18:e0187824. doi: 10.1128/spectrum.01878-24. Online ahead of print.ABSTRACTChronic tinnitus is a central nervous system disorder. Currently, the effects of gut microbiota on tinnitus remain unexplored. To explore the connection between gut microbiota and tinnitus, we conducted 16S rRNA sequencing of fecal microbiota and serum metabolomic analysis in a cohort of 70 patients with tinnitus and 30 healthy volunteers. We used the weighted gene co-expression network method to analyze the relationship between the gut microbiota and the serum metabolites. The random forest technique was utilized to select metabolites and gut taxa to construct predictive models. A pronounced gut dysbiosis in the tinnitus group, characterized by reduced bacterial diversity, an increased Firmicutes/Bacteroidetes ratio, and some opportunistic bacteria including Aeromonas and Acinetobacter were enriched. In contrast, some beneficial gut probiotics decreased, including Lactobacillales and Lactobacillaceae. In serum metabolomic analysis, serum metabolic disturbances in tinnitus patients and these differential metabolites were enriched in pathways of neuroinflammation, neurotransmitter activity, and synaptic function. The predictive models exhibited great diagnostic performance, achieving 0.94 (95% CI: 0.85-0.98) and 0.96 (95% CI: 0.86-0.99) in the test set. Our study suggests that changes in gut microbiota could potentially influence the occurrence and chronicity of tinnitus, and exert regulatory effects through changes in serum metabolites. Overall, this research provides new perceptions into the potential role of gut microbiota and serum metabolite in the pathogenesis of tinnitus, and proposes the "gut-brain-ear" concept as a pathomechanism underlying tinnitus, with significant clinical diagnostic implications and therapeutic potential.IMPORTANCETinnitus affects millions of people worldwide. Severe cases may lead to sleep disorders, anxiety, and depression, subsequently impacting patients' lives and increasing societal healthcare expenditures. However, tinnitus mechanisms are poorly understood, and effective therapeutic interventions are currently lacking. We discovered the gut microbiota and serum metabolomics changes in patients with tinnitus, and provided the potential pathological mechanisms of dysregulated gut flora in chronic tinnitus. We proposed the innovative concept of the "gut-brain-ear axis," which underscores the exploration of gut microbiota impact on susceptibility to chronic tinnitus through serum metabolic profile modulation. We also reveal novel biomarkers associated with chronic tinnitus, offering a new conceptual framework for further investigations into the susceptibility of patients, potential treatment targets for tinnitus, and assessing patient prognosis. Subsequently, gut microbiota and serum metabolites can be used as molecular markers to assess the susceptibility and prognosis of tinnitus.Furthermore, fecal transplantation may be used to treat tinnitus.PMID:39555931 | DOI:10.1128/spectrum.01878-24
RNAseq and targeted metabolomics implicate RIC8 in regulation of energy homeostasis, amino acid compartmentation, and asexual development in Neurospora crassa
mBio. 2024 Nov 18:e0313324. doi: 10.1128/mbio.03133-24. Online ahead of print.ABSTRACTHeterotrimeric G protein signaling pathways control growth and development in eukaryotes. In the multicellular fungus Neurospora crassa, the guanine nucleotide exchange factor RIC8 regulates heterotrimeric Gα subunits. In this study, we used RNAseq and liquid chromatography-mass spectrometry (LC-MS) to profile the transcriptomes and metabolomes of N. crassa wild type, the Gα subunit mutants Δgna-1 and Δgna-3, and Δric8 strains. These strains exhibit defects in growth and asexual development (conidiation), with wild-type and Δgna-1 mutants producing hyphae in submerged cultures, while Δgna-3 and Δric8 mutants develop conidiophores, particularly in the Δric8 mutant. RNAseq analysis showed that the Δgna-1 mutant possesses 159 mis-regulated genes, while Δgna-3 and Δric8 strains have more than 1,000 each. Many of the mis-regulated genes are involved in energy homeostasis, conidiation, or metabolism. LC-MS revealed changes in levels of primary metabolites in the mutants, with several arginine metabolic intermediates impacted in Δric8 strains. The differences in metabolite levels could not be fully explained by the expression or activity of pathway enzymes. However, transcript levels for two predicted vacuolar arginine transporters were affected in Δric8 mutants. Analysis of arginine and ornithine levels in transporter mutants yielded support for altered compartmentation of arginine and ornithine between the cytosol and vacuole in Δric8 strains. Furthermore, we validated previous reports that arginine and ornithine levels are low in wild-type conidia. Our results suggest that RIC8 regulates asexual sporulation in N. crassa at least in part through altered expression of vacuolar transporter genes and the resultant mis-compartmentation of arginine and ornithine.IMPORTANCE: Resistance to inhibitors of cholinesterase-8 (RIC8) is an important regulator of heterotrimeric Gα proteins in eukaryotes. In the filamentous fungus Neurospora crassa, mutants lacking ric8 undergo inappropriate asexual development (macroconidiation) during submerged growth. Our work identifies a role for RIC8 in regulating expression of transporter genes that retain arginine and ornithine in the vacuole (equivalent of the animal lysosome) and relates this function to the developmental defect. Arginine is a critical cellular metabolite, both as an amino acid for protein synthesis and as a precursor for an array of compounds, including proline, ornithine, citrulline, polyamines, creatine phosphate, and nitric oxide. These results have broad relevance to human physiology and disease, as arginine modulates immune, vascular, hormonal, and other functions in humans.PMID:39555920 | DOI:10.1128/mbio.03133-24
Melatonin Ameliorates Cadmium-Induced Liver Fibrosis Via Modulating Gut Microbiota and Bile Acid Metabolism
J Pineal Res. 2024 Nov;76(8):e70005. doi: 10.1111/jpi.70005.ABSTRACTCadmium (Cd) is a widespread environmental contaminant with high toxicity to human health. Melatonin has been shown to improve Cd-induced liver damage. However, its mechanism has not yet been elucidated. In this study, we aimed to investigate the effects of melatonin on Cd-induced liver damage and fibrosis. A combination of 16S rRNA gene sequencing and mass spectrometry-based metabolomics was adopted to investigate changes in the gut microbiome and its metabolites on the regulation of melatonin in Cd-induced liver injury and fibrosis of mice. Further, nonabsorbable antibiotics, a fecal microbiota transplantation (FMT) program and intestine-specific farnesoid X receptor (FXR) knockout mice were employed to explore the mechanism of melatonin (MT) on liver injury and fibrosis in Cd treated mice. MT significantly improved hepatic inflammation, bile duct hyperplasia, liver damage, and liver fibrosis, with a notable decrease in liver bile acid levels in Cd-exposed mice. MT treatment remodeled the gut microbiota, improved gut barrier function, and reduced the production of gut-derived lipopolysaccharide (LPS). MT significantly decreased the intestinal tauro-β-muricholic acid levels, which are known as FXR antagonists. Notably, MT prominently activated the intestinal FXR signaling, subsequently inhibiting liver bile acid synthesis and decreasing hepatic inflammation in Cd-exposed mice. However, MT could not ameliorate Cd-induced liver damage and fibrosis in Abx-treated mice. Conversely, MT still exerted a protective effect on Cd-induced liver damage and fibrosis in FMT mice. Interestingly, MT failed to reverse liver damage and fibrosis in Cd-exposed intestinal epithelial cell-specific FXR gene knockout mice, indicating that intestinal FXR signaling mediated the protective effect of MT treatment. MT improves Cd-induced liver damage and fibrosis through reshaping the intestinal flora, activating the intestinal FXR-mediated suppression of liver bile acid synthesis and reducing LPS leakage in mice.PMID:39555739 | DOI:10.1111/jpi.70005
Functional characterization reveals the importance of Arabidopsis ECA4 and EPSIN3 in clathrin mediated endocytosis and wall structure in apical growing cells
New Phytol. 2024 Nov 18. doi: 10.1111/nph.20282. Online ahead of print.ABSTRACTLocalized clathrin mediated endocytosis is vital for secretion and wall deposition in apical growing plant cells. Adaptor and signalling proteins, along with phosphoinositides, are known to play a regulatory, yet poorly defined role in this process. Here we investigated the function of Arabidopsis ECA4 and EPSIN3, putative mediators of the process, in pollen tubes and root hairs. Homozygous eca4 and epsin3 plants exhibited altered pollen tube morphology (in vitro) and self-pollination led to fewer seeds and shorter siliques. These effects were augmented in eca4/epsin3 double mutant and quantitative polymerase chain reaction data revealed changes in phosphoinositide metabolism and flowering genes suggestive of a synergistic action. No visible changes were observed in root morphology, but atomic force microscopy in mutant root hairs showed altered structural stiffness. Imaging and FRET-FLIM analysis of ECA4 and EPSIN3 X-FP constructs revealed that both proteins interact at the plasma membrane but exhibit slightly different intracellular localization. FT-ICR-MS metabolomic analysis of mutant cells showed changes in lipids, amino acids and carbohydrate composition consistent with a role in secretion and growth. Characterization of double mutants of eca4 and epsin3 with phospholipase C genes (plc5, plc7) indicates that phosphoinositides (e.g. PtdIns(4,5)P2) are fundamental for a combined and complementary role of ECA4-EPSIN3 in cell secretion.PMID:39555685 | DOI:10.1111/nph.20282
Dietary Effects of Probiotic Bacteria, Bacillus amyloliquefaciens AV5 on Growth, Serum and Mucus Immune Response, Metabolomics, and Lipid Metabolism in Nile Tilapia (Oreochromis niloticus)
Aquac Nutr. 2024 Aug 12;2024:4253969. doi: 10.1155/2024/4253969. eCollection 2024.ABSTRACTIn the present study, we investigated the effect of dietary supplementation with the probiotic Bacillus amyloliquefaciens AV5 (OR647358) on the growth, serum and mucus immune responses, metabolomics, and lipid metabolism of Oreochromis niloticus. Fishes (27.2 ± 1.7 g and 9.0 ± 1.2 cm) were fed three distinct meals: a commercial diet (control-GC) and two treatment diets supplemented with probiotics at 106 (G1) and 108 cfu/g (G2), respectively, for 30 days. In the G2 group, the final weight, specific growth rate, weight gain rate, survival rate, and feed conversion ratio of the fish were significantly improved (p < 0.05). Lysozyme, myeloperoxidase, and alkaline phosphatase activities in the mucus of fish were significantly higher (p < 0.05) in the G1 and G2 groups. The serum total protein, superoxide dismutase, glutathione peroxidase, reactive oxygen species, and reactive nitrogen species levels were noticeably higher (p < 0.05) in fish fed G1 and G2. In addition, in the G1 and G2 groups, higher levels of enzymes involved in lipid metabolism, such as pyruvate kinase, 2-hydroxyethyl-ThPP, and dihydrolipoamide dehydrogenase, were increased. Distal gastrointestinal metabolites, such as glycerophospholipids and histidine, were observed. These findings strongly indicate that incorporating B. amyloliquefaciens AV5 at 108 cfu/g into commercial feeds positively influences fish growth, immunity, and lipid metabolism.PMID:39555520 | PMC:PMC11333138 | DOI:10.1155/2024/4253969
Effects of Tannin Supplementation in Diet on the Resistance to Ammonia Stress of Pacific White Shrimp <em>Litopenaeus vannamei</em>
Aquac Nutr. 2024 May 13;2024:5539701. doi: 10.1155/2024/5539701. eCollection 2024.ABSTRACTTannin (TA), as a natural phenolic compound with strong antioxidant activity, has been used as a feed additive for various animals. In this study, we fed a diet containing 800 mg/kg of tannin on Litopenaeus vannamei for 56 days and then subjected to acute ammonia stress for 48 hr to investigate the effect of dietary tannin on the ammonia stress response of L. vannamei through transcriptomic and metabolomic analysis. The transcriptome analysis indicated that ammonia stress-induced differential expression of 4,185 genes, while tannin-fed shrimp only had 964 differentially expressed genes. Compared with the TA_0 group, 59 pathways were significantly altered, and the pathways of "starch and sucrose metabolism," "retinol metabolism," "arachidonic acid metabolism," "lysosome," and "amino sugar and nucleotide sugar metabolism" were highly enriched in the TS_0 group. Compared with the TS_0 group, six pathways were significantly altered, and the pathways of "dilated cardiomyopathy," "complement and coagulation cascades," "cardiac muscle contraction," "fructose and mannose metabolism," "cGMP-PKG signaling pathway," and "beta-alanine metabolism" were significantly enriched in the TS_800 group. Metabolomic analysis showed that a total of 107 differential metabolites (DMs) were identified in the TS_0 vs. TA_0 group, while 75 DMs were identified in the TS_800 vs. TS_0 group. Based on KEGG annotation, it was found that a large amount of DM was significantly enriched in amino acid metabolism pathways in the TS_0 group, including "arginine and proline metabolism," "alanine, aspartic acid, and glutamic acid metabolism," "β-Alanine metabolism and tyrosine metabolism" indicated that tannins affect the metabolism of amino acids. The integration of DEGs and DMs indicates that dietary tannins highly alter the digestion and absorption functions of proteins, as well as the biosynthesis and metabolism of amino acids. This study provides new insights into the adaptation of Pacific white shrimp to ammonia stress and the addition of tannins to feed to enhance immune function.PMID:39555517 | PMC:PMC11105962 | DOI:10.1155/2024/5539701
Toxic effects of DEHP and MEHP on gut-liver axis in rats via intestinal flora and metabolomics
iScience. 2024 Oct 10;27(11):111135. doi: 10.1016/j.isci.2024.111135. eCollection 2024 Nov 15.ABSTRACTDi (2-ethylhexyl) phthalate (DEHP) is an environmental endocrine disruptor and commonly used as a plasticizer. Exposure to DEHP and its active metabolite mono-2-ethylhexyl phthalate (MEHP) can lead to adverse health consequences; however, the toxic mechanism is remains unclear. In this research, male and female rats were exposed to DEHP and MEHP by oral gavage for 60 consecutive days. Pathological analysis revealed that DEHP and MEHP exposure could affect liver, heart, kidney, and testis tissues, as well as alter biochemical indicators. Metagenomics (16S rRNA gene sequencing) analysis indicated that DEHP and MEHP could reduce the diversity and alter the composition of the gut microbiota. Toxic exposure also affected the levels of short chain fatty acids (SCFAs), with noticeable variations between genders. Metabolomic analysis revealed that DEHP and MEHP could influence bile acids, amino acids, hormones, and lipids. These results demonstrate that exposure to DEHP and MEHP can induce toxicity in rats via the gut-liver axis.PMID:39555414 | PMC:PMC11565036 | DOI:10.1016/j.isci.2024.111135