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Biology subjects

Yang, K.-T.

Publications and source records attributed to Yang, K.-T..

3 recordsLinked to original sources

Paraspeckles translate microbial insult-induced inflammation into neurovascular remodeling by enhancing CYR61-FGF2 signaling via RBM14 sequestration

BackgroundSystemic inflammation triggered by microbial insults can disrupt endothelial homeostasis, impair blood-brain and blood-retinal barriers, leading to neurovascular remodeling in the central nervous system (CNS). Subnuclear condensates, paraspeckles, play a substantial role in stress-induced gene regulation, yet their contribution to the inflammatory relay from microbial insults to neurovascular remodeling remains unelucidated. ResultsOur comparative transcriptomic analysis followed by experimental validation identified a cross-species NEAT1_2/CYR61/FGF2 signature in the CNS positively associated with neurovascular remodeling across human disease cohorts and multiple mouse models. Notably, systemic inflammation triggered by microbial insults, including sepsis or gut dysbiosis, enhanced NEAT1_2 expression in the brain and retina with neurovascular remodeling. Microbial insults induced hyper-assembly of paraspeckles and the expression of CYR61 and FGF2 in vascular endothelial cells. Paraspeckle assembly and its required NEAT1_2 Domain C, rather than NEAT1_2 expression levels, play a pivotal role in endothelial homeostasis control and neurovascular remodeling by sequestering the RNA-binding protein RBM14 from the CYR61 promoter, thereby relieving its repression of CYR61 transcription. Moreover, secreted CYR61 enhanced FGF2-mediated endothelial remodeling signals in a paracrine manner. Disrupting paraspeckle assembly by targeting Domain C intercepts neurovascular remodeling, restoring endothelial homeostasis in vivo. ConclusionsOur results demonstrate an essential and conserved role for paraspeckles in the inflammatory relay from microbial insults to neurovascular remodeling by sequestering RBM14 to enhance CYR61-FGF2 signaling. Furthermore, our study underscores paraspeckle assembly as a promising therapeutic target for neurovascular remodeling and related diseases.

molecular biology↗

Molecular Imaging with Fibroblast Activation Protein Tracers depicts Inflammatory Joint Damage and its Transition to Resolution of Inflammation

Joint fibroblasts play an important role in the transition from joint inflammation to irreversible joint damage. There is no established clinical method to measure fibroblast activation during inflammation and their phenotypic dynamics upon therapy to date. Here we show that upon treatment with IL-17A/TNF-blocking antibodies fibroblasts change their phenotype from a destructive IL-6+/MMP3+THY1+ to a CD200+DKK3+ subtype, actively inducing resolution of inflammation. This phenotypic switch can be visualized due to so far unexplored different capacities of fibroblast subtypes with regard to receptor internalization of small molecular tracers with high affinity to FAP. Although FAP expression levels are comparable between fibroblast subtypes in the joint, FAP internalisation rate correlates with the destructive potential of fibroblasts and resolving fibroblasts have a lower FAP internalisation rate, providing a valuable imaging tool to visualize the transition from joint damage to resolution of inflammation.

immunology↗

Macrophages inhibit Coxiella burnetii by the ACOD1-itaconate pathway for containment of Q fever

Infection with the intracellular bacterium Coxiella (C.) burnetii can cause chronic Q fever with severe complications and limited treatment options. Here, we identify the enzyme cis- aconitate decarboxylase 1 (ACOD1 or IRG1) and its product itaconate as protective host immune pathway in Q fever. Infection of mice with C. burnetii induced expression of several anti-microbial candidate genes, including Acod1. In macrophages, Acod1 was essential for restricting C. burnetii replication, while other antimicrobial pathways were dispensable. Intratracheal or intraperitoneal infection of Acod1-/- mice caused increased C. burnetii burden, significant weight loss and stronger inflammatory gene expression. Exogenously added itaconate restored pathogen control in Acod1-/- mouse macrophages and blocked replication in human macrophages. In axenic cultures, itaconate directly inhibited growth of C. burnetii. Finally, treatment of infected Acod1-/-mice with itaconate efficiently reduced the tissue pathogen load. Thus, ACOD1-derived itaconate is a key factor in the macrophage-mediated defense against C. burnetii and may be exploited for novel therapeutic approaches in chronic Q fever.

immunology↗