To explore the effects and underlying mechanisms of Mdivi-1 on three common clinical models of acute kidney injury (AKI). Three common AKI cell models were constructed, classified into the control group (human renal tubular epithelial cells [HK-2] cells), the Iohexol group (HK-2 cells treated with Iohexol), the Genta group (HK-2 cells treated with Gentamicin), and the Cis group (HK-2 cells treated with Cisplatin). To explore the optimal protective concentration of Mdivi-1 for each AKI cell model, the experimental design consisted of the following seven groups: the control group (HK-2 cells cultured in medium), three injury groups (HK-2 cells subjected to Iohexol, Gentamicin, or Cisplatin), and the corresponding protection groups (with a certain concentration of Mdivi-1 added to each injury group). Cellular survival and apoptosis, reactive oxygen species (ROS) levels, and the expression of recombinant Sirtuin 3 (SIRT3) in each group were measured. Mitochondrial fission and fusion dynamics in cells were observed under an electron microscope. To explore relevant pathways, the changes in relevant pathway proteins were analyzed through Western blotting. The half maximal inhibitory concentration (IC50) values were 150.06 mgI/ml at 6 h in the Iohexol group, 37.88 mg/ml at 24 h in the Gentamicin group, and 13.48 microM at 24 h in the Cisplatin group. Compared with the control group, the three injury groups showed increased cell apoptosis rates and higher expressions of apoptotic proteins in HK-2 cells, with an accompanying decrease in cell migration. After the addition of corresponding concentrations of Mdivi-1, the optimal concentrations were 3 μM in the Iohexo-3 group, 1 microM in the Genta-1 group, and 5 μM in the Cis-5 group, HK-2 cells showed the highest survival rate, reduced apoptosis, decreased mitochondrial ROS and SIRT3 expression, and reduced mitochondrial fission and autophagy when compared with each injury group. Further verification with Western blot analysis after the addition of Mdivi-1 revealed a reduction in the expressions of mitochondrial fission proteins DRP1, Nrf2, SIRT3, Caspase-3, Jun N-terminal Kinase (JNK)/P-JNK, NF-kappaB, Bcl2, and autophagic protein P62, as well as reduced ROS levels. Mdivi-1 had protective effects on the three common AKI cell models by potentially reducing mitochondrial fission in cells and inhibiting the production of ROS through the mediation of the NF- B/JNK/SIRT3 signaling pathway, thereby exerting protective effects. Key words AKI, Cisplatin, Gentamicin, Iohexol, Mdivi-1.
- MeSH
- akutní poškození ledvin * metabolismus patologie farmakoterapie MeSH
- apoptóza účinky léků MeSH
- buněčné linie MeSH
- lidé MeSH
- MAP kinasový signální systém účinky léků fyziologie MeSH
- mitochondriální dynamika * účinky léků fyziologie MeSH
- NF-kappa B * metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- signální transdukce * účinky léků MeSH
- sirtuin 3 * metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
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
The accumulation of senescent cells drives inflammaging and increases morbidity of chronic inflammatory lung diseases. Immune responses are built upon dynamic changes in cell metabolism that supply energy and substrates for cell proliferation, differentiation, and activation. Metabolic changes imposed by environmental stress and inflammation on immune cells and tissue microenvironment are thus chiefly involved in the pathophysiology of allergic and other immune-driven diseases. Altered cell metabolism is also a hallmark of cell senescence, a condition characterized by loss of proliferative activity in cells that remain metabolically active. Accelerated senescence can be triggered by acute or chronic stress and inflammatory responses. In contrast, replicative senescence occurs as part of the physiological aging process and has protective roles in cancer surveillance and wound healing. Importantly, cell senescence can also change or hamper response to diverse therapeutic treatments. Understanding the metabolic pathways of senescence in immune and structural cells is therefore critical to detect, prevent, or revert detrimental aspects of senescence-related immunopathology, by developing specific diagnostics and targeted therapies. In this paper, we review the main changes and metabolic alterations occurring in senescent immune cells (macrophages, B cells, T cells). Subsequently, we present the metabolic footprints described in translational studies in patients with chronic asthma and chronic obstructive pulmonary disease (COPD), and review the ongoing preclinical studies and clinical trials of therapeutic approaches aiming at targeting metabolic pathways to antagonize pathological senescence. Because this is a recently emerging field in allergy and clinical immunology, a better understanding of the metabolic profile of the complex landscape of cell senescence is needed. The progress achieved so far is already providing opportunities for new therapies, as well as for strategies aimed at disease prevention and supporting healthy aging.
- MeSH
- chronická nemoc MeSH
- chronická obstrukční plicní nemoc metabolismus farmakoterapie imunologie MeSH
- lidé MeSH
- metabolické sítě a dráhy * MeSH
- plicní nemoci etiologie farmakoterapie metabolismus imunologie MeSH
- stárnutí buněk * účinky léků MeSH
- stárnutí imunologie metabolismus MeSH
- zánět metabolismus imunologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The RNA editing enzyme adenosine deaminase acting on RNA 1 (ADAR1) is essential for correct functioning of innate immune responses. The ADAR1p110 isoform is mainly nuclear and ADAR1p150, which is interferon (IFN) inducible, is predominately cytoplasmic. Using three different methods - co-immunoprecipitation (co-IP) of endogenous ADAR1, Strep-tag co-IP and BioID with individual ADAR1 isoforms - a comprehensive interactome was generated during both homeostasis and the IFN response. Both known and novel interactors as well as editing regulators were identified. Nuclear proteins were detected as stable interactors with both ADAR1 isoforms. In contrast, BioID identified distinct protein networks for each ADAR1 isoform, with nuclear components observed with ADAR1p110 and components of cytoplasmic cellular condensates with ADAR1p150. RNase A digestion distinguished between distal and proximal interactors, as did a double-stranded RNA (dsRNA)-binding mutant of ADAR1 which demonstrated the importance of dsRNA binding for ADAR1 interactions. IFN treatment did not affect the core ADAR1 interactomes but resulted in novel interactions, the majority of which are proximal interactions retained after RNase A treatment. Short treatment with high molecular weight poly(I:C) during the IFN response resulted in dsRNA-binding-dependent changes in the proximal protein network of ADAR1p110 and association of the ADAR1p150 proximal protein network with some components of antiviral stress granules.
- MeSH
- adenosindeaminasa * metabolismus genetika MeSH
- buněčné jádro * metabolismus MeSH
- cytoplazma * metabolismus MeSH
- dvouvláknová RNA metabolismus genetika MeSH
- editace RNA MeSH
- HEK293 buňky MeSH
- HeLa buňky MeSH
- interferony metabolismus genetika MeSH
- lidé MeSH
- mapy interakcí proteinů MeSH
- poly I-C farmakologie MeSH
- protein - isoformy * metabolismus genetika MeSH
- proteiny vázající RNA * metabolismus genetika MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This study summarizes the response of cyanobacterium Spirulina subsalsa HKAR-19 under simulated light conditions of photosynthetically active radiation (PAR), PAR+UV-A (PA), and PAR+UV-A+UV-B (PAB). Exposure to UV radiation caused a significant (P < 0.05) decrease in chlorophyll a, phycocyanin, and total protein. In contrast, total carotene content increased significantly (P < 0.05) under PA and PAB with increasing irradiation time. The photosynthetic efficiency of photosystem II also decreased significantly in PA and PAB radiation. We have also recorded a decrease in the fluorescence emission intensity of phycocyanin under PA and PAB exposure. The phycocyanin fluorescence shifted towards shorter wavelengths (blue-shift) after 72 h of PA and PAB exposure. Intracellular reactive oxygen species (ROS) levels increased significantly in PA and PAB. Fluorescence microscopic images showed an increase in green fluorescence, indicating ROS generation in UV radiation. We have also quantified ROS generation using green and red fluorescence ratio represented as G/R ratio. A 2-6-fold increase in antioxidative enzymes activity was observed to overcome the damaging effects caused by UV stress as compared to untreated control cultures. The lipid peroxidation was assessed in terms of malondialdehyde content which increases significantly (P < 0.05) as the duration of exposure increases. These results suggest that a combined effect of PAR, UV-A, and UV-B was more deleterious than an individual one.
- MeSH
- antioxidancia * metabolismus MeSH
- chlorofyl a metabolismus MeSH
- chlorofyl * metabolismus MeSH
- fotosyntéza * účinky záření MeSH
- fotosystém II (proteinový komplex) metabolismus MeSH
- fykocyanin * metabolismus MeSH
- karotenoidy metabolismus MeSH
- peroxidace lipidů účinky záření MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- Spirulina * účinky záření metabolismus MeSH
- ultrafialové záření * MeSH
- Publikační typ
- časopisecké články MeSH
The molecular mechanisms linking obstructive sleep apnea syndrome (OSA) to obesity and the development of metabolic diseases are still poorly understood. The role of hypoxia (a characteristic feature of OSA) in excessive fat accumulation has been proposed. The present study investigated the possible effects of hypoxia (4% oxygen) on de novo lipogenesis by tracking the major carbon sources in differentiating 3T3-L1 adipocytes. Gas-permeable cultuware was employed to cultivate 3T3-L1 adipocytes in hypoxia (4%) for 7 or 14 days of differentiation. We investigated the contribution of glutamine, glucose or acetate using 13C or 14C labelled carbons to the newly synthesized lipid pool, changes in intracellular lipid content after inhibiting citrate- or acetate-dependent pathways and gene expression of involved key enzymes. The results demonstrate that, in differentiating adipocytes, hypoxia decreased the synthesis of lipids from glucose (44.1 ± 8.8 to 27.5 ± 3.0 pmol/mg of protein, p < 0.01) and partially decreased the contribution of glutamine metabolized through the reverse tricarboxylic acid cycle (4.6% ± 0.2-4.2% ± 0.1%, p < 0.01). Conversely, the contribution of acetate, a citrate- and mitochondria-independent source of carbons, increased upon hypoxia (356.5 ± 71.4 to 649.8 ± 117.5 pmol/mg of protein, p < 0.01). Further, inhibiting the citrate- or acetate-dependent pathways decreased the intracellular lipid content by 58% and 73%, respectively (p < 0.01) showing the importance of de novo lipogenesis in hypoxia-exposed adipocytes. Altogether, hypoxia modified the utilization of carbon sources, leading to alterations in de novo lipogenesis in differentiating adipocytes and increased intracellular lipid content.
- MeSH
- acetáty * metabolismus farmakologie MeSH
- buněčná diferenciace * účinky léků MeSH
- buňky 3T3-L1 * MeSH
- citrátový cyklus MeSH
- glukosa * metabolismus MeSH
- glutamin * metabolismus MeSH
- hypoxie buňky MeSH
- lipidy biosyntéza MeSH
- lipogeneze * účinky léků MeSH
- metabolismus lipidů účinky léků MeSH
- myši MeSH
- tukové buňky * metabolismus účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Protein synthesis plays a major role in homeostasis and when dysregulated leads to various pathologies including cancer. To this end, imbalanced expression of eukaryotic translation initiation factors (eIFs) is not only a consequence but also a driver of neoplastic growth. eIF3 is the largest, multi-subunit translation initiation complex with a modular assembly, where aberrant expression of one subunit generates only partially functional subcomplexes. To comprehensively study the effects of eIF3 remodeling, we contrasted the impact of eIF3d, eIF3e or eIF3h depletion on the translatome of HeLa cells using Ribo-seq. Depletion of eIF3d or eIF3e, but not eIF3h reduced the levels of multiple components of the MAPK signaling pathways. Surprisingly, however, depletion of all three eIF3 subunits increased MAPK/ERK pathway activity. Depletion of eIF3e and partially eIF3d also increased translation of TOP mRNAs that encode mainly ribosomal proteins and other components of the translational machinery. Moreover, alterations in eIF3 subunit stoichiometry were often associated with changes in translation of mRNAs containing short uORFs, as in the case of the proto-oncogene MDM2 and the transcription factor ATF4. Collectively, perturbations in eIF3 subunit stoichiometry exert specific effect on the translatome comprising signaling and stress-related transcripts with complex 5' UTRs that are implicated in homeostatic adaptation to stress and cancer.
The eIF4F translation initiation complex plays a critical role in melanoma resistance to clinical BRAF and MEK inhibitors. In this study, we uncover a function of eIF4F in the negative regulation of the rat sarcoma (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling pathway. We demonstrate that eIF4F is essential for controlling ERK signaling intensity in treatment-naïve melanoma cells harboring BRAF or NRAS mutations. Specifically, the dual-specificity phosphatase DUSP6/MKP3, which acts as a negative feedback regulator of ERK activity, requires continuous production in an eIF4F-dependent manner to limit excessive ERK signaling driven by oncogenic RAF/RAS mutations. Treatment with small-molecule eIF4F inhibitors disrupts the negative feedback control of MAPK signaling, leading to ERK hyperactivation and EGR1 overexpression in melanoma cells in vitro and in vivo. Furthermore, our quantitative analyses reveal a high spare signaling capacity in the ERK pathway, suggesting that eIF4F-dependent feedback keeps the majority of ERK molecules inactive under normal conditions. Overall, our findings highlight the crucial role of eIF4F in regulating ERK signaling flux and suggest that pharmacological eIF4F inhibitors can disrupt the negative feedback control of MAPK activity in melanomas with BRAF and NRAS activating mutations.
- MeSH
- eukaryotický iniciační faktor 4F * metabolismus genetika MeSH
- extracelulárním signálem regulované MAP kinasy metabolismus MeSH
- fosfatasa 6 s dvojí specificitou metabolismus genetika MeSH
- GTP-fosfohydrolasy * metabolismus genetika MeSH
- lidé MeSH
- MAP kinasový signální systém * genetika MeSH
- melanom * genetika metabolismus patologie MeSH
- membránové proteiny * metabolismus genetika MeSH
- mutace * MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- protoonkogenní proteiny B-Raf * genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Úvod: Dutina ústní představuje komplexní systém, kde probíhá vzájemná chemická komunikace mezi tkáněmi, mikrobiotou a složkami sliny a potravy. Tento článek je zaměřen na hormetické efekty a elektrofilní sloučeniny, které mohou hrát roli v obranných mechanismech proti oxidačnímu stresu a zánětlivým procesům. Hormetické efekty, vyvolané subletálními nebo subtoxickými stresory, mohou aktivovat reparační mechanismy a posílit odolnost tkání proti poškození. Metodika: Analýza byla provedena prostřednictvím vyhledávání ve třech elektronických databázích: Web of Science, PubMed a Scopus. V rámci rešerše jsme se soustředili na studie publikované mezi lety 2000 a 2023, které se zabývaly oxidačně-redukčními procesy, zánětlivými stavy a aktivací Nrf2 dráhy v ústní dutině. Vyloučeny byly studie zaměřené na nádorová onemocnění. Závěr: Elektrofilní sloučeniny působí jako jeden z činitelů zasahujících do homeostázy dutiny ústní a mohou tak představovat terapeutický potenciál v zubním lékařství, konkrétně v parodontologii. Zjištění založená na in vitro a preklinických studiích však vyžadují další ověření v klinických podmínkách, přičemž je třeba zvážit i interakce s orální mikrobiotou.
Introduction: The oral cavity is a complex system in which mutual chemical communication occurs between tissues, microbiota, and components of saliva and food. This paper focuses on hormetic effects and electrophilic compounds, which can play a role in defense mechanisms against oxidative stress and inflammatory processes. Hormetic effects, induced by sublethal or subtoxic stressors, can activate repair mechanisms and enhance tissue resistance to damage. Methods: The analysis was conducted through searches in three electronic databases: Web of Science, PubMed, and Scopus. Our research focused on studies published between 2000 and 2023 that dealt with redox processes, inflammatory conditions, and activation of the Nrf2 pathway in the oral cavity. Studies focused on cancerous diseases were excluded. Conclusion: Electrophilic compounds act as one of the agents that interfere with the homeostasis of the oral cavity, and can thus find therapeutic potential in dentistry, specifically in periodontology. However, findings based on in vitro and preclinical studies require further verification under clinical conditions, and also considering interactions with oral microbiota.
Tumor cells often adapt to amino acid deprivation through metabolic rewiring, compensating for the loss with alternative amino acids/substrates. We have described such a scenario in leukemic cells treated with L-asparaginase (ASNase). Clinical effect of ASNase is based on nutrient stress achieved by its dual enzymatic action which leads to depletion of asparagine and glutamine and is accompanied with elevated aspartate and glutamate concentrations in serum of acute lymphoblastic leukemia patients. We showed that in these limited conditions glutamate uptake compensates for the loss of glutamine availability. Extracellular glutamate flux detection confirms its integration into the TCA cycle and its participation in nucleotide and glutathione synthesis. Importantly, it is glutamate-driven de novo synthesis of glutathione which is the essential metabolic pathway necessary for glutamate's pro-survival effect. In vivo findings support this effect by showing that inhibition of glutamate transporters enhances the therapeutic effect of ASNase. In summary, ASNase induces elevated extracellular glutamate levels under nutrient stress, which leads to a rewiring of intracellular glutamate metabolism and has a negative impact on ASNase treatment.
- MeSH
- akutní lymfatická leukemie farmakoterapie metabolismus patologie MeSH
- asparaginasa * farmakologie metabolismus MeSH
- citrátový cyklus účinky léků MeSH
- glutamin metabolismus MeSH
- glutathion * metabolismus MeSH
- kyselina glutamová * metabolismus MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- protinádorové látky farmakologie MeSH
- xenogenní modely - testy protinádorové aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
