| 1. |
- Gómez Rodríguez, Alexia, et al.
(författare)
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Elovl2-Ablation Leads to Mitochondrial Membrane Fatty Acid Remodeling and Reduced Efficiency in Mouse Liver Mitochondria
- 2022
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643. ; 14:3
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Tidskriftsartikel (refereegranskat)abstract
- The fatty acid elongase elongation of very long-chain fatty acids protein 2 (ELOVL2) controls the elongation of polyunsaturated fatty acids (PUFA) producing precursors for omega-3, docosahexaenoic acid (DHA), and omega-6, docosapentaenoic acid (DPAn-6) in vivo. Expectedly, Elovl2-ablation drastically reduced the DHA and DPAn-6 in liver mitochondrial membranes. Unexpectedly, however, total PUFAs levels decreased further than could be explained by Elovl2 ablation. The lipid peroxidation process was not involved in PUFAs reduction since malondialdehyde-lysine (MDAL) and other oxidative stress biomarkers were not enhanced. The content of mitochondrial respiratory chain proteins remained unchanged. Still, membrane remodeling was associated with the high voltage-dependent anion channel (VDAC) and adenine nucleotide translocase 2 (ANT2), a possible reflection of the increased demand on phospholipid transport to the mitochondria. Mitochondrial function was impaired despite preserved content of the respiratory chain proteins and the absence of oxidative damage. Oligomycin-insensitive oxygen consumption increased, and coefficients of respiratory control were reduced by 50%. The mitochondria became very sensitive to fatty acid-induced uncoupling and permeabilization, where ANT2 is involved. Mitochondrial volume and number of peroxisomes increased as revealed by transmission electron microscopy. In conclusion, the results imply that endogenous DHA production is vital for the normal function of mouse liver mitochondria and could be relevant not only for mice but also for human metabolism.
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| 2. |
- Leuti, Alessandro, et al.
(författare)
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Macrophage Plasticity and Polarization Are Altered in the Experimental Model of Multiple Sclerosis
- 2021
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Ingår i: Biomolecules. - : MDPI AG. - 2218-273X. ; 11:6
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Tidskriftsartikel (refereegranskat)abstract
- Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system. MS is characterized by infiltrations of leukocytes such as T and B lymphocytes and macrophages. Macrophages have been identified as major effectors of inflammation and demyelination in both MS and its animal model, experimental autoimmune encephalomyelitis (EAE). However, the activation and heterogeneity of macrophages in MS has been poorly investigated. Thus, in this study, we evaluated M1 and M2 macrophages immunophenotype from EAE and control mice by analyzing over 30 surface and intracellular markers through polychromatic flow cytometry, qRT-PCR, and ELISA assay. We showed that M1 macrophages possessed a higher proinflammatory profile in EAE compared to control mice, since they expressed higher levels of activation/co-stimulatory markers (iNOS, CD40, and CD80) and cytokines/chemokines (IL-6, IL-12, CCL2, and CXCL10), whereas M2 lost their M2-like phenotype by showing a decreased expression of their signature markers CD206 and CCL22, as well as a concomitant upregulation of several M1 makers. Furthermore, immunization of M1 and M2 macrophages with MOG35-55 led to a significant hyperactivation of M1 and a concomitant shift of anti-inflammatory M2 to pro-inflammatory M1 macrophages. Overall, we provide evidence for a phenotypic alteration of M1/M2 balance during MS, which can be of crucial importance not only for a better understanding of the immunopathology of this neurodegenerative disease but also to potentially develop new macrophage-centered therapeutic strategies.
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| 3. |
- Pauter, Anna M., et al.
(författare)
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Both maternal and offspring Elovl2 genotypes determine systemic DHA levels in perinatal mice
- 2017
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Ingår i: Journal of Lipid Research. - 0022-2275 .- 1539-7262. ; 58:1, s. 111-123
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Tidskriftsartikel (refereegranskat)abstract
- The molecular details relevant to dietary supplementation of the omega-3 fatty acid DHA in mothers as well as in their offspring are not clear. The PUFA elongase, elongation of very long-chain fatty acid (ELOVL) 2, is a critical enzyme in the formation of DHA in mammals. In order to address the question regarding the origin of DHA during perinatal life, we have used DHA-deficient Elovl2-ablated mice as a model system to analyze the maternal impact on the DHA level in their offspring of various genotypes. Elovl2(-/-) mothers maintained on control diet had significantly lower systemic levels of DHA compared with the Elovl2(+/-) and Elovl2(+/+) mothers. Dietary DHA administration during the pregnancy and lactation periods led to increased DHA accretion in maternal tissues and serum of all genotypes. The proportion of DHA in the liver and serum of the Elovl2(-/-) offspring was significantly lower than in the Elovl2(+/+) offspring. Remarkably, the DHA level in the Elovl2(+/-) offspring nursed by DHA-free-fed Elovl2(-/-) mothers was almost as high as in +/+ pups delivered by +/+ mothers, suggesting that endogenous synthesis in the offspring can compensate for maternal DHA deficiency.(Jlr) Maternal DHA supplementation had a strong impact on offspring hepatic gene expression, especially of the fatty acid transporter, Mfsd2a, suggesting a dynamic interplay between DHA synthesis and DHA uptake in the control of systemic levels in the offspring.
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| 4. |
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| 5. |
- Pauter, Anna M., et al.
(författare)
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Synergistic Effects of DHA and Sucrose on Body Weight Gain in PUFA-Deficient Elovl2-/- Mice
- 2019
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Ingår i: Nutrients. - : MDPI AG. - 2072-6643. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- The omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) is implicated in the regulation of both lipid and carbohydrate metabolism. Thus, we questioned whether dietary DHA and low or high content of sucrose impact on metabolism in mice deficient for elongation of very long-chain fatty acids 2 (ELOVL2), an enzyme involved in the endogenous DHA synthesis. We found that Elovl2 -/- mice fed a high-sucrose DHA-enriched diet followed by the high sucrose, high fat challenge significantly increased body weight. This diet affected the triglyceride rich lipoprotein fraction of plasma lipoproteins and changed the expression of several genes involved in lipid metabolism in a white adipose tissue. Our findings suggest that lipogenesis in mammals is synergistically influenced by DHA dietary and sucrose content.
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| 6. |
- Talamonti, Emanuela, et al.
(författare)
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Impairment of DHA synthesis alters the expression of neuronal plasticity markers and the brain inflammatory status in mice
- 2020
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Ingår i: The FASEB Journal. - 0892-6638 .- 1530-6860. ; 34:2, s. 2024-2040
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Tidskriftsartikel (refereegranskat)abstract
- Docosahexaenoic acid (DHA) is a omega-3 fatty acid typically obtained from the diet or endogenously synthesized through the action of elongases (ELOVLs) and desaturases. DHA is a key central nervous system constituent and the precursor of several molecules that regulate the resolution of inflammation. In the present study, we questioned whether the impaired synthesis of DHA affected neural plasticity and inflammatory status in the adult brain. To address this question, we investigated neural and inflammatory markers from mice deficient for ELOVL2 (Elovl2(-/-)), the key enzyme in DHA synthesis. From our findings, Elovl2(-/-) mice showed an altered expression of markers involved in synaptic plasticity, learning, and memory formation such as Egr-1, Arc1, and BDNF specifically in the cerebral cortex, impacting behavioral functions only marginally. In parallel, we also found that DHA-deficient mice were characterized by an increased expression of pro-inflammatory molecules, namely TNF, IL-1 beta, iNOS, caspase-1 as well as the activation and morphologic changes of microglia in the absence of any brain injury or disease. Reintroducing DHA in the diet of Elovl2(-/-) mice reversed such alterations in brain plasticity and inflammation. Hence, impairment of systemic DHA synthesis can modify the brain inflammatory and neural plasticity status, supporting the view that DHA is an essential fatty acid with an important role in keeping inflammation within its physiologic boundary and in shaping neuronal functions in the central nervous system.
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| 7. |
- Talamonti, Emanuela, et al.
(författare)
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Impairment of Endogenous Synthesis of Omega-3 DHA Exacerbates T-Cell Inflammatory Responses
- 2023
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Ingår i: International Journal of Molecular Sciences. - : MDPI AG. - 1661-6596 .- 1422-0067. ; 24:4
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Tidskriftsartikel (refereegranskat)abstract
- Omega-3 (ω-3) polyunsaturated fatty acids, including docosahexaenoic acid (DHA), are involved in numerous biological processes and have a range of health benefits. DHA is obtained through the action of elongases (ELOVLs) and desaturases, among which Elovl2 is the key enzyme involved in its synthesis, and can be further metabolized into several mediators that regulate the resolution of inflammation. Our group has recently reported that ELOVL2 deficient mice (Elovl2−/−) not only display reduced DHA levels in several tissues, but they also have higher pro-inflammatory responses in the brain, including the activation of innate immune cells such as macrophages. However, whether impaired synthesis of DHA affects cells of adaptive immunity, i.e., T lymphocytes, is unexplored. Here we show that Elovl2−/− mice have significantly higher lymphocytes in peripheral blood and that both CD8+ and CD4+ T cell subsets produce greater amounts of pro-inflammatory cytokines in both blood and spleen compared to wild type mice, with a higher percentage of cytotoxic CD8+ T cells (CTLs) as well as IFN-γ-producing Th1 and IL-17-producing Th17 CD4+ cells. Furthermore, we also found that DHA deficiency impacts the cross-talk between dendritic cells (DC) and T cells, inasmuch as mature DCs of Elovl2−/− mice bear higher expression of activation markers (CD80, CD86 and MHC-II) and enhance the polarization of Th1 and Th17 cells. Reintroducing DHA back into the diets of Elovl2−/− mice reversed the exacerbated immune responses observed in T cells. Hence, impairment of endogenous synthesis of DHA exacerbates T cell inflammatory responses, accounting for an important role of DHA in regulating adaptive immunity and in potentially counteracting T-cell-mediated chronic inflammation or autoimmunity.
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| 8. |
- Talamonti, Emanuela, et al.
(författare)
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Impairment of systemic DHA synthesis affects macrophage plasticity and polarization : implications for DHA supplementation during inflammation
- 2017
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Ingår i: Cellular and Molecular Life Sciences (CMLS). - : Springer Science and Business Media LLC. - 1420-682X .- 1420-9071. ; 74:15, s. 2815-2826
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Tidskriftsartikel (refereegranskat)abstract
- Docosahexaenoic acid (DHA) is an omega-3 fatty acid obtained from the diet or synthesized from alpha-linolenic acid through the action of fatty acid elongases (ELOVL) and desaturases. DHA plays important roles in the central nervous system as well as in peripheral organs and is the precursor of several molecules that regulate resolution of inflammation. In the present study, we questioned whether impaired synthesis of DHA affected macrophage plasticity and polarization both in vitro and in vivo models. For this we investigated the activation status and inflammatory response of bone marrow-derived M1 and M2 macrophages obtained from mice deficient of Elovl2 (Elovl2(-/-)), a key enzyme for DHA synthesis in mammals. Although both wild type and Elovl2(-/-)mice were able to generate efficient M1 and M2 macrophages, M1 cells derived from Elovl2(-/-)mice showed an increased expression of key markers (iNOS, CD86 and MARCO) and cytokines (IL-6, IL-12 and IL-23). However, M2 macrophages exhibited upregulated M1-like markers like CD80, CD86 and IL-6, concomitantly with a downregulation of their signature marker CD206. These effects were counteracted in cells obtained from DHA-supplemented animals. Finally, white adipose tissue of Elovl2(-/-) mice presented an M1-like pro-inflammatory phenotype. Hence, impairment of systemic DHA synthesis delineates an alteration of M1/M2 macrophages both in vitro and in vivo, with M1 being hyperactive and more pro-inflammatory while M2 less protective, supporting the view that DHA has a key role in controlling the balance between pro-and anti-inflammatory processes.
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