Alterations in tricarboxylic acid (TCA) cycle metabolism are associated with hepatic metabolic disorders. Elevated hepatic acetate concentrations, often attributed to high caloric intake, are recognized as a pivotal factor in the etiology of obesity and metabolic syndrome. Therefore, the assessment of acetate breakdown and TCA cycle activity plays a central role in understanding the impact of diet-induced alterations on liver metabolism. Magnetic resonance-based deuterium metabolic imaging (DMI) could help to unravel the underlying mechanisms involved in disease development and progression, however, the application of conventional deuterated glucose does not lead to substantial enrichment in hepatic glutamine and glutamate. This study aimed to demonstrate the feasibility of DMI for tracking deuterated acetate breakdown via the TCA cycle in lean and diet-induced fatty liver (FL) rats using 3D DMI after an intraperitoneal infusion of sodium acetate-d3 at 9.4T. Localized and nonlocalized liver spectra acquired at 10 time points post-injection over a 130-min study revealed similar intrahepatic acetate uptake in both animal groups (AUCFL = 717.9 ± 131.1 mM▯min-1, AUClean = 605.1 ± 119.9 mM▯min-1, p = 0.62). Metabolic breakdown could be observed in both groups with an emerging glutamine/glutamate (Glx) peak as a downstream metabolic product (AUCFL = 113.6 ± 23.8 mM▯min-1, AUClean = 136.7 ± 41.7 mM▯min-1, p = 0.68). This study showed the viability of DMI for tracking substrate flux through the TCA cycle, underscoring its methodological potential for imaging metabolic processes in the body.
- MeSH
- acetáty metabolismus MeSH
- analýza metabolického toku MeSH
- citrátový cyklus * MeSH
- deuterium * MeSH
- játra * metabolismus diagnostické zobrazování MeSH
- krysa rodu rattus MeSH
- magnetická rezonanční tomografie MeSH
- potkani Sprague-Dawley MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Escherichia coli A0 34/86 (EcO83) is a probiotic strain used in newborns to prevent nosocomial infections and diarrhoea. This bacterium stimulates both pro- and anti-inflammatory cytokine production and its intranasal administration reduces allergic airway inflammation in mice. Despite its benefits, there are concerns about the use of live probiotic bacteria due to potential systemic infections and gene transfer. Extracellular vesicles (EVs) derived from EcO83 (EcO83-EVs) might offer a safer alternative to live bacteria. This study characterizes EcO83-EVs and investigates their interaction with host cells, highlighting their potential as postbiotic therapeutics. EcO83-EVs were isolated, purified, and characterised following the Minimal Information of Studies of Extracellular Vesicles (MISEV) guidelines. Ex vivo studies conducted in human nasal epithelial cells showed that EcO83-EVs increased the expression of proteins linked to oxidative stress and inflammation, indicating an effective interaction between EVs and the host cells. Further in vivo studies in mice demonstrated that EcO83-EVs interact with nasal-associated lymphoid tissue, are internalised by airway macrophages, and stimulate neutrophil recruitment in the lung. Mechanistically, EcO83-EVs activate the NF-κΒ signalling pathway, resulting in the nitric oxide production. EcO83-EVs demonstrate significant potential as a postbiotic alternative to live bacteria, offering a safer option for therapeutic applications. Further research is required to explore their clinical use, particularly in mucosal vaccination and targeted immunotherapy strategies.
- MeSH
- aplikace intranazální * MeSH
- epitelové buňky metabolismus MeSH
- Escherichia coli * metabolismus MeSH
- extracelulární vezikuly * metabolismus MeSH
- lidé MeSH
- lymfoidní tkáň metabolismus MeSH
- makrofágy metabolismus MeSH
- myši MeSH
- NF-kappa B metabolismus MeSH
- oxidační stres MeSH
- plíce mikrobiologie metabolismus MeSH
- probiotika * aplikace a dávkování MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Size control is a fundamental question in biology, showing incremental complexity in plants, whose cells possess a rigid cell wall. The phytohormone auxin is a vital growth regulator with central importance for differential growth control. Our results indicate that auxin-reliant growth programs affect the molecular complexity of xyloglucans, the major type of cell wall hemicellulose in eudicots. Auxin-dependent induction and repression of growth coincide with reduced and enhanced molecular complexity of xyloglucans, respectively. In agreement with a proposed function in growth control, genetic interference with xyloglucan side decorations distinctly modulates auxin-dependent differential growth rates. Our work proposes that auxin-dependent growth programs have a spatially defined effect on xyloglucan's molecular structure, which in turn affects cell wall mechanics and specifies differential, gravitropic hypocotyl growth.
- MeSH
- Arabidopsis fyziologie MeSH
- buněčná stěna metabolismus MeSH
- fluorescenční protilátková technika MeSH
- fyziologie rostlin * MeSH
- glukany chemie metabolismus MeSH
- hrách setý fyziologie MeSH
- kyseliny indoloctové metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- rostlinné buňky metabolismus MeSH
- signální transdukce MeSH
- vývoj rostlin * MeSH
- xylany chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH