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1.
Ecotoxicol Environ Saf ; 275: 116268, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38569319

RESUMO

Legume-based rotation is commonly recognized for its mitigation efficiency of greenhouse gas (GHG) emissions. However, variations in GHG emission-associated metabolic functions during the legume-vegetable rotation process remain largely uncharacterized. Accordingly, a soybean-radish rotation field experiment was designed to clarify the responses of microbial communities and their GHG emission-associated functional metabolism through metagenomics. The results showed that the contents of soil organic carbon and total phosphorus significantly decreased during the soybean-radish process (P < 0.05), while soil total potassium content and bacterial richness and diversity significantly increased (P < 0.05). Moreover, the predominant bacterial phyla varied, with a decrease in the relative abundance of Proteobacteria and an increase in the relative abundance of Acidobacteria, Gemmatimonadetes, and Chloroflexi. Metagenomics clarified that bacterial carbohydrate metabolism substantially increased during the rotation process, whereas formaldehyde assimilation, methanogenesis, nitrification, and dissimilatory nitrate reduction decreased (P < 0.05). Specifically, the expression of phosphate acetyltransferase (functional methanogenesis gene, pta) and nitrate reductase gamma subunit (functional dissimilatory nitrate reduction gene, narI) was inhibited, indicating of low methane production and nitrogen metabolism. Additionally, the partial least squares path model revealed that the Shannon diversity index was negatively correlated with methane and nitrogen metabolism (P < 0.01), further demonstrating that the response of the soil bacterial microbiome responses are closely linked with GHG-associated metabolism during the soybean-radish rotation process. Collectively, our findings shed light on the responses of soil microbial communities to functional metabolism associated with GHG emissions and provide important insights to mitigate GHG emissions during the rotational cropping of legumes and vegetables.


Assuntos
Fabaceae , Gases de Efeito Estufa , Verduras/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Nitratos , Carbono , Solo , Metano/análise , Nitrogênio/metabolismo , Dióxido de Carbono/análise , Agricultura
2.
Biosci Rep ; 44(4)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38567515

RESUMO

The complex metabolic relationship between the retinal pigment epithelium (RPE) and photoreceptors is essential for maintaining retinal health. Recent evidence indicates the RPE acts as an adjacent lactate sink, suppressing glycolysis in the epithelium in order to maximize glycolysis in the photoreceptors. Dysregulated metabolism within the RPE has been implicated in the pathogenesis of age-related macular degeneration (AMD), a leading cause of vision loss. In the present study, we investigate the effects of four cytokines associated with AMD, TNFα, TGF-ß2, IL-6, and IL-1ß, as well as a cocktail containing all four cytokines, on RPE metabolism using ARPE-19 cells, primary human RPE cells, and ex vivo rat eyecups. Strikingly, we found cytokine-specific changes in numerous metabolic markers including lactate production, glucose consumption, extracellular acidification rate, and oxygen consumption rate accompanied by increases in total mitochondrial volume and ATP production. Together, all four cytokines could potently override the constitutive suppression of glycolysis in the RPE, through a mechanism independent of PI3K/AKT, MEK/ERK, or NF-κB. Finally, we observed changes in glycolytic gene expression with cytokine treatment, including in lactate dehydrogenase subunit and glucose transporter expression. Our findings provide new insights into the metabolic changes in the RPE under inflammatory conditions and highlight potential therapeutic targets for AMD.


Assuntos
Degeneração Macular , Epitélio Pigmentado da Retina , Humanos , Ratos , Animais , Epitélio Pigmentado da Retina/metabolismo , 60645 , Citocinas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Degeneração Macular/genética , Degeneração Macular/metabolismo , Lactatos/metabolismo
3.
Microbiol Res ; 283: 127709, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593579

RESUMO

Bifidobacterium longum subsp. infantis commonly colonizes the human gut and is capable of metabolizing L-fucose, which is abundant in the gut. Multiple studies have focused on the mechanisms of L-fucose utilization by B. longum subsp. infantis, but the regulatory pathways governing the expression of these catabolic processes are still unclear. In this study, we have conducted a structural and functional analysis of L-fucose metabolism transcription factor FucR derived from B. longum subsp. infantis Bi-26. Our results indicated that FucR is a L-fucose-sensitive repressor with more α-helices, fewer ß-sheets, and ß-turns. Transcriptional analysis revealed that FucR displays weak negative self-regulation, which is counteracted in the presence of L-fucose. Isothermal titration calorimetry indicated that FucR has a 2:1 stoichiometry with L-fucose. The key amino acid residues for FucR binding L-fucose are Asp280 and Arg331, with mutation of Asp280 to Ala resulting in a decrease in the affinity between FucR and L-fucose with the Kd value from 2.58 to 11.68 µM, and mutation of Arg331 to Ala abolishes the binding ability of FucR towards L-fucose. FucR specifically recognized and bound to a 20-bp incomplete palindrome sequence (5'-ACCCCAATTACGAAAATTTTT-3'), and the affinity of the L-fucose-loaded FucR for the DNA fragment was lower than apo-FucR. The results provided new insights into the regulating L-fucose metabolism by B. longum subsp. infantis.


Assuntos
Bifidobacterium longum , Bifidobacterium , Humanos , Bifidobacterium/genética , Bifidobacterium/metabolismo , Fucose/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Metabolismo dos Carboidratos , Bifidobacterium longum/genética , Bifidobacterium longum/metabolismo
4.
Front Plant Sci ; 15: 1338106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606064

RESUMO

Introduction: Heterologous grafting has been proven to be a valid approach to improving potato fertility, especially when grafting potatoes with other Solanaceae family plants. However, the mechanisms underlying grafting-induced improvement in potato fertility are still unknown. Methods: In this study, a poor-fertility potato cultivar "Qingshu No. 9" (Q9) was grafted with a tomato cultivar "Zhongyan988" (ZY988) to study the effects of heterologous grafting in the former. The tuber yield was controlled by different grafting and cultivation approaches, and the correlation between tuber yield and pollen vigor was studied. Comparative transcriptomic analysis of the potential mechanisms of pollen in potato scion fertility changes. Result: Grafting with the tomato rootstock effectively promoted the flower and fruit formation in the scion potato and improved its pollen viability by 15%-20%. In addition, a significant negative correlation was observed between the potato tuber yield and pollen viability, suggesting a potential impact on the metabolic regulatory network related to tuber formation. From the comparative transcriptomic analysis between the pollens from Q9 self-grafted plants and Q9-tomato grafting scion, 513 differentially expressed genes (DEGs) were identified. These DEGs were found to be related to gametophyte and pollen development, carbohydrate metabolism, and protein processing. Thus, these DEGs might be involved in improved fertility after reduced tuberization in plants subjected to heterologous grafting. Discussion: Potato/tomato heterologous grafting significantly improved the pollen viability of scion potatoes and was associated with the absence of potato tubers. Heterologous grafting promotes the transcription of genes related to protein processing, carbohydrate metabolism, and pollen development in pollen cells, resulting in the production of fertile pollen. Our results provided initial clues to understanding the improvement of potato fertility using the heterologous grafting method, which might be a useful tool in assisted potato breeding.

5.
J Oral Microbiol ; 16(1): 2339161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606339

RESUMO

Objective: To explore the mechanisms underlying the virulence changes in early childhood caries (ECC) caused by Candida albicans (C. albicans) and Streptococcus mutans (S. mutans), with a focus on carbohydrate metabolism and environmental acidification. Methods: A review of literature was conducted to understand the symbiotic relationship between C. albicans and S. mutans, and their role in the pathogenesis of ECC. The review also examined how their interactions influence carbohydrate metabolism and environmental acidification in the oral cavity. Results: C. albicans and S. mutans play crucial roles in the onset and progression of ECC. C. albicans promotes the adhesion and accumulation of S. mutans, while S. mutans creates an environment favorable for the growth of C. albicans. Their interactions, especially through carbohydrate metabolism, strengthen their pathogenic potential. The review highlights the importance of understanding these mechanisms for the development of effective management and treatment protocols for ECC. Conclusion: The symbiotic relationship between C. albicans and S. mutans, and their interactions through carbohydrate metabolism and environmental acidification, are key factors in the pathogenesis of ECC. A comprehensive understanding of these mechanisms is crucial for developing effective strategies to manage and treat ECC.

6.
Plant Physiol Biochem ; 210: 108643, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38653097

RESUMO

Drought priming is known to enhance plant low temperature tolerance, whereas polystyrene nanoplastic contamination exerts detrimental effects on plant growth. This study investigates the less-explored influence of nanoplastic contamination on cold stress tolerance in drought-primed plants. We compared the photosynthetic carbon assimilation, carbohydrate metabolism, reactive oxygen species metabolism, and grain yield between the non-primed and drought-primed wheat grown in both nanoplastic-contaminated and healthy soils. Our results reveal that the beneficial effects of drought priming on photosynthetic carbon assimilation and the efficiency of the "water-water" cycle were compromised in the presence of nanoplastics (nPS). Additionally, nPS exposure disturbed carbohydrate metabolism, which impeded source-to-sink transport of sugar and resulted in reduced grain yield in drought-primed plants under low temperature conditions. These findings unveil the suppression of nPS on drought-primed low-temperature tolerance (DPLT) in wheat plants, suggesting an intricate interplay between the induction of stress tolerance and responses to nPS contamination. The study raises awareness about a potential challenge for future crop production.

7.
BMC Microbiol ; 24(1): 131, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643098

RESUMO

BACKGROUND: Exposure to extreme cold or heat temperature is one leading cause of weather-associated mortality and morbidity in animals. Emerging studies demonstrate that the microbiota residing in guts act as an integral factor required to modulate host tolerance to cold or heat exposure, but common and unique patterns of animal-temperature associations between cold and heat have not been simultaneously examined. Therefore, we attempted to investigate the roles of gut microbiota in modulating tolerance to cold or heat exposure in mice. RESULTS: The results showed that both cold and heat acutely change the body temperature of mice, but mice efficiently maintain their body temperature at conditions of chronic extreme temperatures. Mice adapt to extreme temperatures by adjusting body weight gain, food intake and energy harvest. Fascinatingly, 16 S rRNA sequencing shows that extreme temperatures result in a differential shift in the gut microbiota. Moreover, transplantation of the extreme-temperature microbiota is sufficient to enhance host tolerance to cold and heat, respectively. Metagenomic sequencing shows that the microbiota assists their hosts in resisting extreme temperatures through regulating the host insulin pathway. CONCLUSIONS: Our findings highlight that the microbiota is a key factor orchestrating the overall energy homeostasis under extreme temperatures, providing an insight into the interaction and coevolution of hosts and gut microbiota.


Assuntos
Microbioma Gastrointestinal , Temperatura Alta , Animais , Camundongos , Temperatura , Microbioma Gastrointestinal/fisiologia , Temperatura Baixa , Adaptação Fisiológica/fisiologia
8.
Sci Total Environ ; : 172626, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38657823

RESUMO

Despite the wide acknowledgment that plastic pollution and global warming have become serious agricultural concerns, their combined impact on crop growth remains poorly understood. Given the unabated megatrend, a simulated soil warming (SWT, +4 °C) microcosm experiment was carried out to provide a better understanding of the effects of temperature fluctuations on wheat seedlings exposed to nanoplastics (NPs, 1 g L-1 61.71 ±â€¯0.31 nm polystyrene). It was documented that SWT induced oxidative stress in wheat seedlings grown in NPs-contaminated soil, with an 85.56 % increase in root activity, while decreasing plant height, fresh weight, and leaf area by 8.72 %, 47.68 %, and 15.04 % respectively. The SWT also resulted in reduced photosynthetic electron-transfer reaction and Calvin-Benson cycle in NPs-treated plants. Under NPs, SWT stimulated the tricarboxylic acid (TCA) metabolism and bio-oxidation process. The decrease in photosynthesis and the increase in respiration resulted in an 11.94 % decrease in net photosynthetic rate (Pn). These results indicated the complicated interplay between climate change and nanoplastic pollution in crop growth and underscored the potential risk of nanoplastic pollution on crop production in the future climate.

9.
Wien Klin Wochenschr ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634910

RESUMO

BACKGROUND: A complete review of the development of neonatology in the last 40 years would probably require a compendium with several volumes, to bring to view the remarkable improvements in survival rates and neurodevelopmental outcomes of ill babies in Austria, most industrial countries and to some extent worldwide. The challenge I had to solve here was to integrate my own contributions to the field of neonatology during this period and particularly the contributions of my team from the Division of Neonatology and Pediatric Intensive Care Medicine, Department of Pediatrics and Adolescence Medicine, Medical University Vienna where I was working first as an intern and resident and later had the privilege to become head of department. AIM: This very personal review was conceived to showcase the milestones of neonatology where, in my opinion, our department made some meaningful contributions in research and clinical practice during the past 40 years. METHODS: A total of 10 areas of interest were selected which most likely influenced survival rates of preterm infants born at increasingly younger gestational ages and ameliorated long-term clinical and neurodevelopmental outcomes, including: 1) Construction and continuous modernization of neonatal intensive care units (NICUs). 2) Installation of the "Regionalization Program for NICUs in Vienna". 3) Treatment of respiratory distress syndrome (RDS) of premature babies. 4) Fine tuning of glucose metabolism for growth and outcome. 5) Neurodevelopmental care. 6) Neonatal hematology. 7) Infection control. 8) The toxoplasma screening program. 9) The newborn screening program. 10) Quality control: the Vermont Oxford Neonatal Network (VONN). RESULTS: Over the past four decades advancements in research and technology have allowed a transformative development of neonatal medicine. Survival rates without increased morbidity for very premature infants with gestational ages reaching to what we consider nowadays the border of viability have constantly increased. In my professional life as a neonatologist in Austria I have had the possibility to support and shape some of these developments together with my team. CONCLUSION: As we look ahead it is imperative to build upon the progress made, harnessing the power of science and technology to further improve the survival and quality of life for preterm infants in Austria and worldwide. At the same time, neonatology must continue to prioritize ethical reflection and education, fostering a culture of integrity, interdisciplinary collaboration, and the development of guidelines and protocols that uphold ethical standards while addressing the evolving needs and complexities of neonatal medicine.

10.
Food Microbiol ; 121: 104487, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637064

RESUMO

Streptococcus thermophilus is a bacterium widely used in the production of yogurts and cheeses, where it efficiently ferments lactose, the saccharide naturally present in milk. It is also employed as a starter in dairy- or plant-based fermented foods that contain saccharides other than lactose (e.g., sucrose, glucose). However, little is known about how saccharide use is regulated, in particular when saccharides are mixed. Here, we determine the effect of the 5 sugars that S. thermophilus is able to use, at different concentration and when they are mixed on the promoter activities of the C-metabolism genes. Using a transcriptional fusion approach, we discovered that lactose and glucose modulated the activity of the lacS and scrA promoters in a concentration-dependent manner. When mixed with lactose, glucose also repressed the two promoter activities; when mixed with sucrose, lactose still repressed scrA promoter activity. We determined that catabolite control protein A (CcpA) played a key role in these dynamics. We also showed that promoter activity was linked with glycolytic flux, which varied depending on saccharide type and concentration. Overall, this study identified key mechanisms in carbohydrate metabolism - autoregulation and partial hierarchical control - and demonstrated that they are partly mediated by CcpA.


Assuntos
Glucose , Lactose , Lactose/metabolismo , Glucose/metabolismo , Metabolismo dos Carboidratos , Glicólise , Streptococcus thermophilus/genética , Streptococcus thermophilus/metabolismo , Sacarose/metabolismo
11.
Bull Exp Biol Med ; 176(4): 481-485, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38492104

RESUMO

We performed complex analysis of the association of polymorphic variants rs7903146 of the TCF7L2 gene and rs1801282 of the PPARG gene with metabolic parameters, insulin resistance, and ß-cell function in a group of patients with early signs of carbohydrate metabolism disturbances in a sample of Tyumen citizens. The study group consisted of 64 people (39 women, 25 men) aged 40-70 years. The distribution of frequencies of alleles and genotypes of the polymorphic markers rs7903146 and rs1801282 was analyzed and associations of carriage of major homozygous polymorphisms with various phenotypic traits were identified. Genotyping for polymorphic variants of TCF7L2 and PPARG genes was performed using allele-specific PCR with primers provided by Synthol company. Carriers of homozygotes for allele C of the polymorphic marker rs7903146 significantly differed from other respondents by a higher level of C-peptide, as well as by the presence of associations with waist circumference, elevated level of glycated hemoglobin, and arterial hypertension. Carriers of homozygotes for the allele C of the rs1801282 polymorphism of the PPARG gene differed from the group of carriers of homozygotes for the allele G and the group of heterozygote carriers by higher levels of triglycerides, as well as the presence of associations with waist circumference and the level of glycated hemoglobin.


Assuntos
Diabetes Mellitus Tipo 2 , PPAR gama , Proteína 2 Semelhante ao Fator 7 de Transcrição , Feminino , Humanos , Masculino , Metabolismo dos Carboidratos , Diabetes Mellitus Tipo 2/genética , Genótipo , Hemoglobinas Glicadas/genética , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética , PPAR gama/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética
12.
Metabolites ; 14(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38535316

RESUMO

Stress-induced fetal programming diminishes ß2 adrenergic tone, which coincides with intrauterine growth restriction (IUGR) and lifelong metabolic dysfunction. We determined if stimulating ß2 adrenergic activity in IUGR-born lambs would improve metabolic outcomes. IUGR lambs that received daily injections of saline or the ß2 agonist clenbuterol from birth to 60 days were compared with controls from pair-fed thermoneutral pregnancies. As juveniles, IUGR lambs exhibited systemic inflammation and robust metabolic dysfunction, including greater (p < 0.05) circulating TNFα, IL-6, and non-esterified fatty acids, increased (p < 0.05) intramuscular glycogen, reduced (p < 0.05) circulating IGF-1, hindlimb blood flow, glucose-stimulated insulin secretion, and muscle glucose oxidation. Daily clenbuterol fully recovered (p < 0.05) circulating TNFα, IL-6, and non-esterified fatty acids, hindlimb blood flow, muscle glucose oxidation, and intramuscular glycogen. Glucose-stimulated insulin secretion was partially recovered (p < 0.05) in clenbuterol-treated IUGR lambs, but circulating IGF-1 was not improved. Circulating triglycerides and HDL cholesterol were elevated (p < 0.05) in clenbuterol-treated IUGR lambs, despite being normal in untreated IUGR lambs. We conclude that deficient ß2 adrenergic regulation is a primary mechanism for several components of metabolic dysfunction in IUGR-born offspring and thus represents a potential therapeutic target for improving metabolic outcomes. Moreover, benefits from the ß2 agonist were likely complemented by its suppression of IUGR-associated inflammation.

13.
J Clin Invest ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512401

RESUMO

Bacterial translocation from the gut microbiota is a source of sepsis in susceptible patients. Previous work suggests that overgrowth of gut pathobionts, including Klebsiella pneumoniae, increases the risk of disseminated infection. Our data from a human dietary intervention study found that in the absence of fiber, K. pneumoniae bloomed during microbiota recovery from antibiotic treatment. We thus hypothesized that dietary nutrients directly support or suppress colonization of this gut pathobiont in the microbiota. Consistent with our human subject study, complex carbohydrates in dietary fiber suppressed colonization of K. pneumoniae and allowed for recovery of competing commensals in mouse modeling. In contrast, through ex-vivo and in vivo modeling, we identify simple carbohydrates as a limiting resource for K. pneumoniae in the gut. As proof of principle, supplementation with lactulose, a non-absorbed simple carbohydrate and an FDA approved therapy, increased colonization of K. pneumoniae. Disruption of the intestinal epithelium led to dissemination of K. pneumoniae into the bloodstream and liver, which was prevented by dietary fiber. Our results show that dietary simple and complex carbohydrates are critical not only in the regulation of pathobiont colonization but also disseminated infection, suggesting that targeted dietary interventions may offer a preventative strategy in high-risk patients.

14.
Diabetologia ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483543

RESUMO

AIMS/HYPOTHESIS: The aim of the present study was to conduct a randomised, placebo-controlled, double-blind, crossover trial to determine whether pre-meal ketone monoester ingestion reduces postprandial glucose concentrations in individuals with type 2 diabetes. METHODS: In this double-blind, placebo-controlled, crossover design study, ten participants with type 2 diabetes (age 59±1.7 years, 50% female, BMI 32±1 kg/m2, HbA1c 54±2 mmol/mol [7.1±0.2%]) were randomised using computer-generated random numbers. The study took place at the Nutritional Physiology Research Unit, University of Exeter, Exeter, UK. Using a dual-glucose tracer approach, we assessed glucose kinetics after the ingestion of a 0.5 g/kg body mass ketone monoester (KME) or a taste-matched non-caloric placebo before a mixed-meal tolerance test. The primary outcome measure was endogenous glucose production. Secondary outcome measures were total glucose appearance rate and exogenous glucose appearance rate, glucose disappearance rate, blood glucose, serum insulin, ß-OHB and NEFA levels, and energy expenditure. RESULTS: Data for all ten participants were analysed. KME ingestion increased mean ± SEM plasma beta-hydroxybutyrate from 0.3±0.03 mmol/l to a peak of 4.3±1.2 mmol/l while reducing 2 h postprandial glucose concentrations by ~18% and 4 h postprandial glucose concentrations by ~12%, predominately as a result of a 28% decrease in the 2 h rate of glucose appearance following meal ingestion (all p<0.05). The reduction in blood glucose concentrations was associated with suppressed plasma NEFA concentrations after KME ingestion, with no difference in plasma insulin concentrations between the control and KME conditions. Postprandial endogenous glucose production was unaffected by KME ingestion (mean ± SEM 0.76±0.15 and 0.88±0.10 mg kg-1 min-1 for the control and KME, respectively). No adverse effects of KME ingestion were observed. CONCLUSIONS/INTERPRETATION: KME ingestion appears to delay glucose absorption in adults with type 2 diabetes, thereby reducing postprandial glucose concentrations. Future work to explore the therapeutic potential of KME supplementation in type 2 diabetes is warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT05518448. FUNDING: This project was supported by a Canadian Institutes of Health Research (CIHR) Project Grant (PJT-169116) and a Natural Sciences and Engineering Research Council (NSERC) Discovery Grant (RGPIN-2019-05204) awarded to JPL and an Exeter-UBCO Sports Health Science Fund Project Grant awarded to FBS and JPL.

15.
Plant Physiol Biochem ; 208: 108464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442629

RESUMO

Low temperature-induced cold stress is a major threat to plant growth, development and distribution. Unraveling the responses of temperature-sensitive crops to cold stress and the mechanisms of cold acclimation are critical for food demand. In this study, combined physiological, transcriptomic, and metabolomic analyses were conducted on Nicotiana tabacum suffering short-term 4 °C cold stress. Our results showed that cold stress destroyed cellular membrane stability, decreased the chlorophyll (Chl) and carotenoid contents, and closed stomata, resulting in lipid peroxidation and photosynthesis restriction. Chl fluorescence measurements revealed that primary photochemistry, photoelectrochemical quenching and photosynthetic electron transport in Nicotiana tabacum leaves were seriously suppressed upon exposer to cold stress. Enzymatic and nonenzymatic antioxidants, including superoxide dismutase, catalase, peroxidase, reduced glutathione, proline, and soluble sugar, were all profoundly increased to trigger the cold acclimation defense against oxidative damage. A total of 178 metabolites and 16,204 genes were differentially expressed in cold-stressed Nicotiana tabacum leaves. MEturquoise and MEblue modules identified by WGCNA were highly correlated with physiological indices, and the corresponding hub genes were significantly enriched in pathways related to photosynthesis - antenna proteins and flavonoid biosynthesis. Untargeted metabolomic analysis identified specific metabolites, including sucrose, phenylalanine, glutamine, glutamate, and proline, that enhance plant cold acclimation. Combined transcriptomics and metabolomic analysis highlight the vital roles of carbohydrate and amino acid metabolism in enhancing the cold tolerance of Nicotiana tabacum. Our comprehensive investigation provides novel insights for efforts to alleviate low temperature-induced oxidative damage to Nicotiana tabacum plants and proposes a breeding target for cold stress-tolerant cultivars.


Assuntos
Resposta ao Choque Frio , Tabaco , Resposta ao Choque Frio/genética , Tabaco/genética , Perfilação da Expressão Gênica , Fotossíntese/fisiologia , Metabolômica , Prolina/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Temperatura Baixa
16.
Physiol Mol Biol Plants ; 30(1): 123-136, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38435855

RESUMO

This study aimed to explore the mechanism by which calcium (Ca) signal regulated carbohydrate metabolism and exogenous Ca alleviated salinity toxicity. Wheat seedlings were treated with sodium chloride (NaCl, 150 mM) alone or combined with 500 µM calcium chloride (CaCl2), lanthanum chloride (LaCl3) and/or ethylene glycol tetraacetic acid (EGTA) to primarily analyse carbohydrate starch and sucrose metabolism, as well as Ca signaling components. Treatment with NaCl, EGTA, or LaCl3 alone retarded wheat-seedling growth and decreased starch content accompanied by weakened ribulose-1,5-bisphosphate carboxylation/oxygenase (Rubisco) and Rubisco activase activities, as well as enhanced glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, alpha-amylase, and beta-amylase activities. However, it increased the sucrose level, up-regulated the sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities and TaSPS and TaSuSy expression together, but down-regulated the acid invertase (SA-Inv) and alkaline/neutral invertase (A/N-Inv) activities and TaSA-Inv and TaA/N-Inv expression. Except for unchanged A/N-Inv activities and TaA/N-Inv expression, adding CaCl2 effectively blocked the sodium salt-induced changes of these parameters, which was partially eliminated by EGTA or LaCl3 presence. Furthermore, NaCl treatment also significantly inhibited Ca-dependent protein kinases and Ca2+-ATPase activities and their gene expression in wheat leaves, which was effectively relieved by adding CaCl2. Taken together, CaCl2 application effectively alleviated the sodium salt-induced retardation of wheat-seedling growth by enhancing starch anabolism and sucrose catabolism, and intracellular Ca signal regulated the enzyme activities and gene expression of starch and sucrose metabolism in the leaves of sodium salt-stressed wheat seedlings.

17.
Sci Rep ; 14(1): 5147, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429352

RESUMO

Rice husk, an agricultural waste from the rice industry, can cause serious environmental pollution if not properly managed. However, rice husk ash (RHA) has been found to have many positive properties, making it a potential replacement for non-renewable peat in soilless planting. Thus, this study investigated the impact of a RHA composite substrate on the growth, photosynthetic parameters, and fruit quality of cucumber (Yuyi longxiang variety) and melon (Yutian yangjiaomi variety). The RHA, peat, vermiculite, and perlite were blended in varying proportions, with the conventional seedling substrate (peat:vermiculite:perlite = 1:1:1 volume ratio) serving as the control (CK). All plants were cultivated in barrels filled with 10L of the mixed substrates. The results from this study found that RHA 40 (RHA:peat:vermiculite:perlite = 4:4:1:1 volume ratio) significantly enhanced substrate ventilation and positively influenced the stem diameter, root activity, seedling index, chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of cucumber and melon plants. Additionally, plant planted using RHA 40, the individual fruit weight of cucumber and melon found to increase by 34.62% and 21.67%, respectively, as compared to the control. Aside from that, both cucumber and melon fruits had significantly higher sucrose, total soluble sugar, vitamin C, and soluble protein levels. This subsequently improved the activity of sucrose synthase and sucrose phosphate synthase in both cucumber and melon. In conclusion, the RHA 40 found to best promote cucumber and melon plant growth, increase plant leaf photosynthesis, and improve cucumber and melon fruit quality, making it a suitable substrate formula for cucumber and melon cultivation in place of peat.


Assuntos
Óxido de Alumínio , Silicatos de Alumínio , Cucumis sativus , Cucurbitaceae , Oryza , Dióxido de Silício , Carboidratos da Dieta , Solo
18.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338742

RESUMO

Plant-growth-promoting rhizobacteria (PGPR) could potentially enhance photosynthesis and benefit plant growth by improving soil nutrient uptake and affecting plant hormone balance. Several recent studies have unveiled a correlation between alterations in photosynthesis and host plant resistance levels. Photosynthesis provides materials and energy for plant growth and immune defense and affects defense-related signaling pathways. Photosynthetic organelles, which could be strengthened by PGPR inoculation, are key centers for defense signal biosynthesis and transmission. Although endophytic PGPRs metabolize plant photosynthates, they can increase soluble sugar levels and alternate sugar type and distribution. Soluble sugars clearly support plant growth and can act as secondary messengers under stressed conditions. Overall, carbohydrate metabolism modifications induced by PGPR may also play a key role in improving plant resistance. We provide a concise overview of current knowledge regarding PGPR-induced modulation in carbohydrate metabolism under both pathogen-infected and pathogen-free conditions. We highlight PGPR application as a cost-saving strategy amidst unpredictable pathogen pressures.


Assuntos
Alphaproteobacteria , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas , Metabolismo dos Carboidratos , Açúcares , Mecanismos de Defesa
19.
NMR Biomed ; : e5123, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38423797

RESUMO

The liver plays a central role in metabolic homeostasis, as exemplified by a variety of clinical disorders with hepatic and systemic metabolic disarrays. Of particular interest are the complex interactions between lipid and carbohydrate metabolism in highly prevalent conditions such as obesity, diabetes, and fatty liver disease. Limited accessibility and the need for invasive procedures challenge direct investigations in humans. Hence, noninvasive dynamic evaluations of glycolytic flux and steady-state assessments of lipid levels and composition are crucial for basic understanding and may open new avenues toward novel therapeutic targets. Here, three different MR spectroscopy (MRS) techniques that have been combined in a single interleaved examination in a 7T MR scanner are evaluated. 1 H-MRS and 13 C-MRS probe endogenous metabolites, while deuterium metabolic imaging (DMI) relies on administration of deuterated tracers, currently 2 H-labelled glucose, to map the spatial and temporal evolution of their metabolic fate. All three techniques have been optimized for a robust single-session clinical investigation and applied in a preliminary study of healthy subjects. The use of a triple-channel 1 H/2 H/13 C RF coil enables interleaved examinations with no need for repositioning. Short-echo-time STEAM spectroscopy provides well resolved spectra to quantify lipid content and composition. The relative benefits of using water saturation versus metabolite cycling and types of respiratory synchronization were evaluated. 2 H-MR spectroscopic imaging allowed for registration of time- and space-resolved glucose levels following oral ingestion of 2 H-glucose, while natural abundance 13 C-MRS of glycogen provides a dynamic measure of hepatic glucose storage. For DMI and 13 C-MRS, the measurement precision of the method was estimated to be about 0.2 and about 16 mM, respectively, for 5 min scanning periods. Excellent results were shown for the determination of dynamic uptake of glucose with DMI and lipid profiles with 1 H-MRS, while the determination of changes in glycogen levels by 13 C-MRS is also feasible but somewhat more limited by signal-to-noise ratio.

20.
Parasit Vectors ; 17(1): 68, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365789

RESUMO

BACKGROUND: Sparganosis is a worldwide food-borne parasitic disease caused by spargana infection, which infects the muscle of frogs and snakes as well as many tissues and organs in humans. There are currently no viable treatments for sparganosis. Understanding spargana's nutrition source and carbohydrate metabolism may be crucial for identifying its energy supply and establishing methods of treatment for sparganosis. METHODS: Using an amino acid analyzer and nutrient concentration detection kits, we assessed nutrient concentrations in the muscles of Fejervarya limnocharis and Pelophylax plancyi infected or not infected with spargana. Quantitative polymerase chain reaction (PCR) was used to quantify the major enzymes involved in five glucose metabolism pathways of spargana developing in vivo. We also used quantitative PCR to assess key enzymes and transcriptome sequencing to explore the regulation of carbohydrate metabolic pathways in vitro in response to different 24-h food treatments. RESULTS: Infected muscle tissues had considerably higher concentrations of glucogenic and/or ketogenic amino acids, glucose, and glycogen than non-infected muscle tissues. We discovered that the number of differentially expressed genes in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was larger in low-glucose than in other dietary groups. We examined differences in the expression of genes producing amino acid transporters, glucose transporters, and cathepsins in spargana grown in various nutritional environments. In the normal saline group, only the major enzymes in the tricarboxylic acid cycle (TCA), glycogenesis, and glycogenolysis pathways were expressed. The L-glutamine group had the greatest transcriptional levels of critical rate-limiting enzymes of gluconeogenesis and glycogenesis. Furthermore, the low-glucose group had the highest transcriptional levels of critical rate-limiting enzymes involved in the TCA, glycolytic, and glycogenolysis pathways. Surprisingly, when compared to the in vitro culturing groups, spargana developing in vivo exhibited higher expression of these critical rate-limiting enzymes in these pathways, with the exception of the pentose phosphate pathway. CONCLUSIONS: Spargana have a variety of nutritional sources, and there is a close relationship between nutrients and the carbohydrate metabolism pathways. It takes a multi-site approach to block nutrient absorption and carbohydrate metabolism pathways to provide energy to kill them.


Assuntos
Esparganose , Plerocercoide , Animais , Humanos , Metabolismo dos Carboidratos , Anuros , Nutrientes , Glucose , Crescimento e Desenvolvimento
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