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Hypoxia triggers reactive microglial inflammation and lipid droplet (LD) accumulation under stroke conditions, although the mutual interactions between these two processes are insufficiently understood. Hence, the involvement of transforming growth factor (TGF)-β1 in inflammation and LD accumulation in cultured microglia exposed to hypoxia were analyzed herein. Primary microglia were exposed to oxygen-glucose deprivation (OGD) injury and lipopolysaccharide (LPS) stimulation. For analyzing the role of TGF-β1 patterns under such conditions, a TGF-β1 siRNA and an exogenous recombinant TGF-β1 protein were employed. Further studies applied Triacsin C, an inhibitor of LD formation, in order to directly assess the impact of LD formation on the modulation of inflammation. To assess mutual microglia-to-neuron interactions, a co-culture model of these cells was established. Upon OGD exposure, microglial TGF-β1 levels were significantly increased, whereas LPS stimulation yielded decreased levels. Elevating TGF-β1 expression proved highly effective in suppressing inflammation and reducing LD accumulation in microglia exposed to LPS. Conversely, inhibition of TGF-β1 led to the promotion of microglial cell inflammation and an increase in LD accumulation in microglia exposed to OGD. Employing the LD formation inhibitor Triacsin C, in turn, polarized microglia towards an anti-inflammatory phenotype. Such modulation of both microglial TGF-β1 and LD levels significantly affected the resistance of co-cultured neurons. This study provides novel insights by demonstrating that TGF-β1 plays a protective role against microglia-mediated neuroinflammation through the suppression of LD accumulation. These findings offer a fresh perspective on stroke treatment, suggesting the potential of targeting this pathway for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis is a type of chronic, progressive, fibrotic lung disease of unclear cause with few treatment options. Cell therapy is emerging as a promising novel modality for facilitating lung repair. Mesenchymal stem cell (MSC)-based and macrophage-based cell therapies are regarded as promising strategies to promote lung repair, due to incredible regenerative potential and typical immunomodulatory function, respectively. Extracellular vesicles (EVs), including exosomes and microvesicles, are cell-derived lipid-bilayer membrane vesicles that are secreted from virtually every cell and are involved in intercellular communication by delivering expansive biological cargos to recipients. This review provides a deep insight into the recent research progress concerning the effects of MSC and macrophage-associated EVs on the pathogenesis of pulmonary fibrosis. In addition to discussing their respective vital roles, we summarize the importance of cross-talk, as macrophages are vital for MSCs to exert their protective effects through two major patterns, including attenuating macrophage activation and M1 phenotype macrophage polarization. Moreover, miRNAs are selectively enriched into EVs as essential components, and consideration is given to the particular effects of EV-associated miRNAs. [ABSTRACT FROM AUTHOR]