Background: Endothelial cell (EC) dysfunction is an early sign of compromised vascular integrity and is associated with various cardiovascular diseases (CVDs). Activation of Toll-like receptor 4 (TLR4) plays a central role in this process. Extracellular vesicles (EVs) derived from milk have known anti-inflammatory properties, particularly in suppressing TLR4 activation. This study investigates the therapeutic potential of human breast milk-derived EVs (HBM-EVs) in mitigating EC dysfunction related to CVDs. Methods: HBM-EVs were isolated from the breast milk of healthy nursing mothers using ultracentrifugation. HBM-EVs were applied to lipopolysaccharide (LPS)-treated human umbilical vein endothelial cells (HUVECs), and inflammatory marker expression was assessed through qPCR and Western blotting. Mitochondrial oxidative stress was measured using MitoSOX. The effects of HBM-EVs were further evaluated in ex vivo studies using mesenteric arteries from diet-induced obese mice. Additionally, the effect of HBM-EVs on angiogenesis was tested via a wound closure assay. Results: In HUVECs, pre-treatment with HBM-EVs inhibited LPS-induced expression of inflammatory markers, including IL-6 and VCAM-1, as well as the phosphorylation of NFκB. Additionally, HBM-EVs reduced LPS-induced mitochondrial oxidative stress. In animal studies, HBM-EV treatment restored EC-dependent vasorelaxation in mesenteric arteries from diet-induced obese mice. Furthermore, HBM-EVs enhanced EC migration, leading to improved wound closure in HUVECs. Conclusion: This study demonstrates the therapeutic potential of HBM-EVs in alleviating EC dysfunction, offering a promising new approach to the treatment of CVDs. Future research will focus on identifying the specific cargo of HBM-EVs and further exploring their therapeutic mechanisms in endothelial dysfunction.

Background: Middle-aged adults have the highest obesity rates, leading to significant health complications in later years. Obesity triggers the release of altered molecules, including extracellular vesicles (EVs) from excess adipose tissue (AT), contributing to various health complications. In this study, we assessed the effects of age and a high-fat diet on AT-derived EV miRNA profiles to understand their potential roles in aging and obesity. Method: C57BL/6 male mice were subjected to a normal chow diet (NCD) or a high-fat diet (HFD) for either 10–12 weeks (young mice, n = 10) or 50–61 weeks (middle-aged mice, n = 12). After evaluating metabolic characteristics, peri-gonadal white AT was isolated and cultured to obtain EVs. AT-derived EV miRNAs were profiled using a NanoString miRNA panel (n = 599). Results: Middle-aged mice exhibited obesity regardless of diet. Young mice fed an HFD showed similar metabolic traits to middle-aged mice. In the NCD group, 131 differentially expressed miRNAs (DE-miRNAs) emerged in middle-aged mice compared to young mice, including miR-21, miR-148a, and miR-29a, associated with cancer, neuro/psychological disorders, and reproductive diseases. In the HFD group, 55 DE-miRNAs were revealed in middle-aged mice compared to young mice. These miRNAs were associated with significantly suppressed IGF1R activity. Conclusion: This study demonstrates the potential significant impact of miRNAs of AT EVs on aging- and obesity-related diseases.