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Biology subjects

Elias-Arnanz, M.

Publications and source records attributed to Elias-Arnanz, M..

3 recordsLinked to original sources

Ether lipid remodeling during neuronal differentiation prevents ferroptosis

Ferroptosis is a form of cell death driven by iron-dependent lipid peroxidation, with specific lipid species playing key roles in modulating susceptibility. Among these, ether lipids have shown conflicting effects, being linked to both protection and sensitization. Here, we dissect the relationship between lipid structure and ferroptosis sensitivity and explain how ether lipids exert context-dependent effects. Ether lipids can promote ferroptosis through a metabolic bias towards the accumulation of polyunsaturated acyl chains and ethanolamine head groups, whereas this pro-ferroptotic tendency is counterbalanced by the anti-ferroptotic vinyl ether moiety introduced by plasmanylethanolamine desaturase 1. We show that this protective effect is critical for preventing ferroptosis in hiPSC-derived neurons, which accumulate otherwise pro-ferroptotic ether lipids during differentiation. This effect is not solely due to its antioxidant properties but also stems from the reprogramming of mitochondrial respiration. The lack of vinyl ether bonds leads to multiple mitochondrial defects, including increased mitochondrial reactive oxygen species (ROS), lower membrane potential, and abnormal cristae structures. These findings indicate that vinyl ether bonds in ether lipids offer dual ferroptosis resistance by scavenging ROS and minimizing its production at the mitochondrial level. The disruption of this system in Caenorhabditis elegans leads to iron-induced death and impaired motility. Thus, our study reveals ether lipid structural remodeling as a key regulator of ferroptosis sensitivity in neurons.

cell biology↗

Origin of Eukaryotic Plasmalogen Biosynthesis by Horizontal Gene Transfer from Myxobacteria

Plasmalogens, a unique class of membrane lipids defined by a distinctive vinyl ether bond, are critical for human health, with their altered levels linked to various diseases. Despite their importance, their origin and evolutionary history remain enigmatic. Here, we uncover the evolutionary history of the aerobic plasmalogen biosynthesis pathway in eukaryotes, focusing on the four essential enzymes responsible for their formation. Through comprehensive phylogenetic analyses and experimental validation, we demonstrate a significant divide in plasmalogen synthesis capabilities across major eukaryotic lineages. Our study also suggests that the acquisition of these plasmalogen biosynthesis genes by an early eukaryotic ancestor was through horizontal gene transfer (HGT) from Myxobacteria. The findings yield insights into how HGT shapes metabolic pathways and illuminate a critical step in the genesis of eukaryotic cell complexity.

evolutionary biology↗

Peds1 deficiency in zebrafish results in myeloid cell apoptosis and exacerbated inflammation

Plasmalogens are glycerophospholipids with a vinyl ether bond that confers unique properties. Recent identification of the gene encoding PEDS1, the desaturase generating the vinyl ether bond, enables evaluation of the role of plasmalogens in health and disease. Here, we report that Peds1-deficient zebrafish larvae display delayed development, increased basal inflammation, normal hematopoietic stem and progenitor cell emergence, and cell-autonomous myeloid cell apoptosis. In a sterile acute inflammation model, Peds1-deficient larvae exhibited impaired inflammation resolution and tissue regeneration, increased interleukin-1{beta} and NF-{kappa}B activities, and elevated ROS levels at the wound site. Abnormal immune cell recruitment, neutrophil persistence, and fewer but predominantly pro-inflammatory macrophages was observed. Chronic skin inflammation worsened in Peds1-deficient larvae but was mitigated by exogenous plasmalogen, which also alleviated hyper-susceptibility to bacterial infection, as did pharmacological inhibition of caspase-3 and colony-stimulating factor 3-induced myelopoiesis. Overall, our results highlight an important role for plasmalogens in myeloid cell biology and inflammation. KeypointsO_LIPlasmalogens are crucial for cell autonomous survival, recruitment and activation of neutrophils and macrophages. C_LIO_LIPlasmalogen production aids inflammation resolution, while supplementation reduces inflammation and boosts bacterial clearance. C_LI

immunology↗