- MeSH
- acyltransferasy MeSH
- arachidonát-12-lipoxygenasa genetika MeSH
- epidermis * MeSH
- fosfolipasy MeSH
- kůže MeSH
- lamelární ichtyóza * MeSH
- lipidy MeSH
- myši MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Peroxiredoxin 6 (Prdx6) is a multifunctional enzyme, a unique member of the peroxiredoxin family, with an important role in antioxidant defense. Moreover, it has also been linked with the biosynthesis of anti-inflammatory and anti-diabetic lipids called fatty acid esters of hydroxy fatty acids (FAHFAs) and many diseases, including cancer, inflammation, and metabolic disorders. Here, we performed metabolomic and lipidomic profiling of subcutaneous adipose tissue from mouse models with genetically modified Prdx6. Deletion of Prdx6 resulted in reduced levels of FAHFAs containing 13-hydroxylinoleic acid (13-HLA). Mutation of Prdx6 C47S impaired the glutathione peroxidase activity and reduced FAHFA levels, while D140A mutation, responsible for phospholipase A2 activity, showed only minor effects. Targeted analysis of oxidized phospholipids and triacylglycerols in adipocytes highlighted a correlation between FAHFA and hydroxy fatty acid production by Prdx6 or glutathione peroxidase 4. FAHFA regioisomer abundance was negatively affected by the Prdx6 deletion, and this effect was more pronounced in longer and more unsaturated FAHFAs. The predicted protein model of Prdx6 suggested that the monomer-dimer transition mechanism might be involved in the repair of longer-chain peroxidized phospholipids bound over two monomers and that the role of Prdx6 in FAHFA synthesis might be restricted to branching positions further from carbon 9. In conclusion, our work linked the peroxidase activity of Prdx6 with the levels of FAHFAs in adipose tissue.
- MeSH
- antioxidancia MeSH
- fosfolipidy MeSH
- mastné kyseliny MeSH
- metabolomika * MeSH
- myši MeSH
- peroxiredoxin VI * genetika MeSH
- peroxiredoxiny MeSH
- tukové buňky MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Inhalation of lead oxide nanoparticles (PbO NPs), which are emitted to the environment by high-temperature technological processes, heavily impairs target organs. These nanoparticles pass through the lung barrier and are distributed via the blood into secondary target organs, where they cause numerous pathological alterations. Here, we studied in detail, macrophages as specialized cells involved in the innate and adaptive immune response in selected target organs to unravel their potential involvement in reaction to subchronic PbO NP inhalation. In this context, we also tackled possible alterations in lipid uptake in the lungs and liver, which is usually associated with foam macrophage formation. RESULTS: The histopathological analysis of PbO NP exposed lung revealed serious chronic inflammation of lung tissues. The number of total and foam macrophages was significantly increased in lung, and they contained numerous cholesterol crystals. PbO NP inhalation induced changes in expression of phospholipases C (PLC) as enzymes linked to macrophage-mediated inflammation in lungs. In the liver, the subchronic inhalation of PbO NPs caused predominantly hyperemia, microsteatosis or remodeling of the liver parenchyma, and the number of liver macrophages also significantly was increased. The gene and protein expression of a cholesterol transporter CD36, which is associated with lipid metabolism, was altered in the liver. The amount of selected cholesteryl esters (CE 16:0, CE 18:1, CE 20:4, CE 22:6) in liver tissue was decreased after subchronic PbO NP inhalation, while total and free cholesterol in liver tissue was slightly increased. Gene and protein expression of phospholipase PLCβ1 and receptor CD36 in human hepatocytes were affected also in in vitro experiments after acute PbO NP exposure. No microscopic or serious functional kidney alterations were detected after subchronic PbO NP exposure and CD68 positive cells were present in the physiological mode in its interstitial tissues. CONCLUSION: Our study revealed the association of increased cholesterol and lipid storage in targeted tissues with the alteration of scavenger receptors and phospholipases C after subchronic inhalation of PbO NPs and yet uncovered processes, which can contribute to steatosis in liver after metal nanoparticles exposure.
- MeSH
- cholesterol MeSH
- fosfolipasy typu C * MeSH
- kovové nanočástice * chemie MeSH
- lidé MeSH
- makrofágy MeSH
- olovo MeSH
- oxidy MeSH
- zánět MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND AND AIMS: We previously identified subsets of patients with NAFLD with different metabolic phenotypes. Here we align metabolomic signatures with cardiovascular disease (CVD) and genetic risk factors. APPROACH AND RESULTS: We analyzed serum metabolome from 1154 individuals with biopsy-proven NAFLD, and from four mouse models of NAFLD with impaired VLDL-triglyceride (TG) secretion, and one with normal VLDL-TG secretion. We identified three metabolic subtypes: A (47%), B (27%), and C (26%). Subtype A phenocopied the metabolome of mice with impaired VLDL-TG secretion; subtype C phenocopied the metabolome of mice with normal VLDL-TG; and subtype B showed an intermediate signature. The percent of patients with NASH and fibrosis was comparable among subtypes, although subtypes B and C exhibited higher liver enzymes. Serum VLDL-TG levels and secretion rate were lower among subtype A compared with subtypes B and C. Subtype A VLDL-TG and VLDL-apolipoprotein B concentrations were independent of steatosis, whereas subtypes B and C showed an association with these parameters. Serum TG, cholesterol, VLDL, small dense LDL5,6 , and remnant lipoprotein cholesterol were lower among subtype A compared with subtypes B and C. The 10-year high risk of CVD, measured with the Framingham risk score, and the frequency of patatin-like phospholipase domain-containing protein 3 NAFLD risk allele were lower in subtype A. CONCLUSIONS: Metabolomic signatures identify three NAFLD subgroups, independent of histological disease severity. These signatures align with known CVD and genetic risk factors, with subtype A exhibiting a lower CVD risk profile. This may account for the variation in hepatic versus cardiovascular outcomes, offering clinically relevant risk stratification.
- MeSH
- apolipoproteiny B MeSH
- fosfolipasy metabolismus MeSH
- játra patologie MeSH
- kardiovaskulární nemoci * epidemiologie etiologie MeSH
- lipoproteiny VLDL MeSH
- myši MeSH
- nealkoholová steatóza jater * patologie MeSH
- rizikové faktory kardiovaskulárních chorob MeSH
- rizikové faktory MeSH
- triglyceridy metabolismus MeSH
- VLDL-cholesterol metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Cells sense a variety of extracellular signals balancing their metabolism and physiology according to changing growth conditions. Plasma membranes are the outermost informational barriers that render cells sensitive to regulatory inputs. Membranes are composed of different types of lipids that play not only structural but also informational roles. Hormones and other regulators are sensed by specific receptors leading to the activation of lipid metabolizing enzymes. These enzymes generate lipid second messengers. Among them, phosphatidic acid (PA) is a well-known intracellular messenger that regulates various cellular processes. This lipid affects the functional properties of cell membranes and binds to specific target proteins leading to either genomic (affecting transcriptome) or non-genomic responses. The subsequent biochemical, cellular and physiological reactions regulate plant growth, development and stress tolerance. In the present review, we focus on primary (genome-independent) signaling events triggered by rapid PA accumulation in plant cells and describe the functional role of PA in mediating response to hormones and hormone-like regulators. The contributions of individual lipid signaling enzymes to the formation of PA by specific stimuli are also discussed. We provide an overview of the current state of knowledge and future perspectives needed to decipher the mode of action of PA in the regulation of cell functions.
- MeSH
- fosfolipasa D * metabolismus MeSH
- hormony metabolismus MeSH
- kyseliny fosfatidové * metabolismus MeSH
- proteiny metabolismus MeSH
- rostlinné proteiny genetika MeSH
- rostliny metabolismus MeSH
- signální transdukce fyziologie MeSH
- vývoj rostlin MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
To date, the effects of specific modification types and sites on protein lifetime have not been systematically illustrated. Here, we describe a proteomic method, DeltaSILAC, to quantitatively assess the impact of site-specific phosphorylation on the turnover of thousands of proteins in live cells. Based on the accurate and reproducible mass spectrometry-based method, a pulse labeling approach using stable isotope-labeled amino acids in cells (pSILAC), phosphoproteomics, and a unique peptide-level matching strategy, our DeltaSILAC profiling revealed a global, unexpected delaying effect of many phosphosites on protein turnover. We further found that phosphorylated sites accelerating protein turnover are functionally selected for cell fitness, enriched in Cyclin-dependent kinase substrates, and evolutionarily conserved, whereas the glutamic acids surrounding phosphosites significantly delay protein turnover. Our method represents a generalizable approach and provides a rich resource for prioritizing the effects of phosphorylation sites on protein lifetime in the context of cell signaling and disease biology.
- MeSH
- buněčný cyklus fyziologie MeSH
- cyklin-dependentní kinasy genetika metabolismus MeSH
- fosfoproteiny chemie metabolismus MeSH
- fosforylace MeSH
- glutamáty metabolismus MeSH
- hmotnostní spektrometrie metody MeSH
- izotopové značení metody MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- peptidy metabolismus MeSH
- peroxiredoxin VI chemie metabolismus MeSH
- proteolýza * MeSH
- proteom genetika metabolismus MeSH
- proteomika metody MeSH
- sekvence aminokyselin MeSH
- sestřihové faktory chemie metabolismus MeSH
- signální transdukce genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
The patatin-like phospholipase domain containing 3 (PNPLA3) gene (viz. its I148M variant) is one of the key players in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). We have identified a novel insertion/deletion variant of 1114 bp, localized in the second intron of the PNPLA3 gene, which corresponds to the 3' terminal sequence of the long-interspersed element (LINE-1). DNA analysis of 122 NAFLD patients and 167 control subjects as well as RNA analysis of 19 liver biopsies revealed that the novel variant is very common (frequency = 0.41), fully linked to the clinically important I148M variant, and clinically silent. Although the LINE-1 insertion does not seem to have any biological effect, it can impede genotyping of the I148M variant. If insertion prevents the attachment of the diagnostic primer, then the non-insertion allele will be selectively amplified; and thus the frequency of the 148M "risk" allele will be significantly overestimated due to the complete linkage of the LINE-1 insertion and the 148I allele of the PNPLA3 gene. Therefore, our findings underline the importance of careful design and consistent documentation of the methodology, including primer sequences. Critical revisions of the results of some studies that have already been reported may therefore be needed.
- MeSH
- acyltransferasy genetika MeSH
- alely MeSH
- dlouhé rozptýlené jaderné elementy genetika MeSH
- fosfolipasy A2 nezávislé na vápníku genetika MeSH
- genetická predispozice k nemoci genetika MeSH
- genotyp MeSH
- játra patologie MeSH
- jednonukleotidový polymorfismus genetika MeSH
- lidé MeSH
- nealkoholová steatóza jater genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The human iPSC cell lines, PLANFiPS1-Sv4F-1 (RCPFi004-A), PLANFiPS2-Sv4F-1 (RCPFi005-A), PLANFiPS3-Sv4F-1 RCPFi006-A), derived from dermal fibroblast from three patients suffering PLAN (PLA2G6-associated neurodegeneration; MIM 256600) caused by mutations in the PLA2G6 gene, was generated by non-integrative reprogramming technology using OCT3/4, SOX2, CMYC and KLF4 reprogramming factors. The pluripotency was assessed by immunocytochemistry and RT-PCR. Differentiation capacity was verified in vitro. This iPSC line can be further differentiated toward affected cells to better understand molecular mechanisms of disease and pathophysiology.
The relationship between baroreflex sensitivity (BRS) and inflammatory vascular biomarker Lipoprotein associated phospholipase A2 (Lp-PLA2) in subjects with high normal blood pressure (HNBP, prehypertensives) with a positive family history of hypertension (FHH+) and hypertension history free control subjects (FHH-) was evaluated. A total of 24 HNBP participants (age 39.5 ± 2.5 years, 18 male/ 6 female) were studied. 14 HNBP subjects FHH+ were compared to 10 HNBP participants FHH-, being of similar age and body mass index. BRS (ms/mmHg) was determined by the sequence and spectral methods (five-minute non-invasive beat-to-beat recording of blood pressure and RR interval, controlled breathing at a frequency of 0.33 Hz). Venous blood was analyzed for Lp-PLA2 biomarker of vascular inflammation and atherothrombotic activity. A significant negative correlation between spontaneous BRS obtained by both methods and systolic blood pressure (BP) was present (BRS spect r = -0.54, P<0.001, BRS seq r = -0.59, P<0.001). BRS obtained by sequence and spectral methods were reduced in HNBP FHH+ compared to the group of HNBP FHH- (P = 0.0317 BRS seq, P = 0.0395 BRS spect). Lp-PLA2 was significantly higher in HNBP FHH+ compared to FHH- controls (P<0.05). Lp-PLA2 was negatively correlated with BRS obtained by sequence method (r = -0.798, R2 = 0.636, P<0.001) in the HNBP FHH+ subjects. These findings demonstrate that reduced baroreflex sensitivity, as a marker of autonomic dysfunction, is associated with vascular inflammation, predominantly in otherwise healthy participants with a positive family history of hypertension who could predispose to increased risk of hypertension. We conclude that our transversal study suggests that a lowbaroreflex sensitivity could be an early sign of autonomic dysfunction even in the prehypertensive period, and to corroborate these findings, a longitudinal study is needed.
- MeSH
- 1-alkyl-2-acetylglycerofosfocholinesterasa krev MeSH
- anamnéza MeSH
- autonomní nervový systém patofyziologie MeSH
- baroreflex * MeSH
- biologické markery krev MeSH
- dospělí MeSH
- hypertenze krev diagnóza enzymologie patofyziologie MeSH
- krevní tlak * MeSH
- lidé středního věku MeSH
- lidé MeSH
- prediktivní hodnota testů MeSH
- rizikové faktory MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Congenital heart disease is the most common type of birth defect, accounting for one-third of all congenital anomalies. Using whole-exome sequencing of 2718 patients with congenital heart disease and a search in GeneMatcher, we identified 30 patients from 21 unrelated families of different ancestries with biallelic phospholipase D1 (PLD1) variants who presented predominantly with congenital cardiac valve defects. We also associated recessive PLD1 variants with isolated neonatal cardiomyopathy. Furthermore, we established that p.I668F is a founder variant among Ashkenazi Jews (allele frequency of ~2%) and describe the phenotypic spectrum of PLD1-associated congenital heart defects. PLD1 missense variants were overrepresented in regions of the protein critical for catalytic activity, and, correspondingly, we observed a strong reduction in enzymatic activity for most of the mutant proteins in an enzymatic assay. Finally, we demonstrate that PLD1 inhibition decreased endothelial-mesenchymal transition, an established pivotal early step in valvulogenesis. In conclusion, our study provides a more detailed understanding of disease mechanisms and phenotypic expression associated with PLD1 loss of function.
- MeSH
- alely * MeSH
- fosfolipasa D * genetika metabolismus MeSH
- lidé MeSH
- mutace ztráty funkce * MeSH
- nemoci srdečních chlopní * enzymologie genetika MeSH
- vrozené srdeční vady * enzymologie genetika MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH