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Biology subjects

Brglez, V.

Publications and source records attributed to Brglez, V..

2 recordsLinked to original sources

p16High immune cell - controlled disease tolerance as a broad defense and healthspan extending strategy

The ability of an organism to overcome infectious diseases has traditionally been linked to killing invading pathogens. Accumulating evidence, however, indicates that, apart from restricting pathogen loads, organismal survival is coupled to an additional yet poorly understood mechanism called disease tolerance. Here we report that p16High immune cells play a key role in establishing disease tolerance. We found that the FDA-approved BNT162b2 mRNA COVID-19 vaccine is a potent and rapid inducer of p16High immune subsets both in mice and humans. In turn, p16High immune cells were indispensable for counteracting different lethal conditions, including LPS-induced sepsis, acute SARS-CoV-2 infection and ionizing irradiation. Mechanistically, we propose that activation of TLR7 or a low physiological activity of STING is sufficient to induce p16High immune subset that, in turn, establishes a low adenosine environment and disease tolerance. Furthermore, containing these signals within a beneficial range by deleting MDA5 that appeared sufficient to maintain a low activity of STING, induces p16High immune cells and delays organ deterioration upon aging with improved healthspan. Our data highlight the beneficial role of p16High immune subsets in establishing a low adenosine environment and disease tolerance.

cell biology↗

Lipid droplets are required for lipid mediator production and cancer cell proliferation

Polyunsaturated fatty acids (PUFAs) are components of membrane phospholipids and precursors of bioactive lipid mediators. Here, we investigated the crosstalk of three pathways providing PUFAs for lipid mediator production: (i) secreted group X phospholipase A2 (GX sPLA2) and (ii) cytosolic group IVA PLA2 (cPLA2), which both mobilize PUFAs from phospholipids, and (iii) adipose triglyceride lipase (ATGL), which breaks down triacylglycerols (TAGs) stored in lipid droplets (LDs). Combining lipidomic and functional analyses, we demonstrate that lipid mediator production depends on TAG turnover. GX sPLA2 directs PUFAs into TAGs and ATGL is required for their entry into lipid mediator biosynthetic pathways. ATGL also promotes the incorporation of LD-derived PUFAs into phospholipids representing substrates for cPLA2. Additionally, inhibition of TAG synthesis mediated by acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) reduces the levels of mitogenic lipid signals and compromises tumour growth. This study expands the paradigm of PLA2-driven lipid mediator signalling and identifies LDs as central lipid mediator production hubs.

cell biology↗