Supporting data for “Human Lipocalin-2 Variants: Therapeutic Evaluations”

Neutrophil extracellular traps (NETs) play a key role in the immune response to inflammatory stimuli but can lead to chronic inflammation when produced in excess. This study investigates the dual role of NETs in both infectious and sterile inflammation, particularly in the context of cardiovascular disease. We focused on the association of lipocalin-2 variants—specifically polyaminated lipocalin-2 (hLcn2), non-polyaminated lipocalin-2 (C87A), and highly polyaminated lipocalin-2 (R81E)—with NETs formation and inflammatory processes. Using transgenic TG-hLcn2/LKO and global lipocalin-2 knockout (LKO) mouse models, we examined the expression of these lipocalin-2 variants during high-fat dietary exposure and assessed their effects on neutrophil lifespan and phenotype.Following a high-fat diet, our findings demonstrated that C87A levels were significantly elevated in cardiac and epididymal white adipose tissue (eWAT). Neutralization with an anti-C87A antibody effectively reduced NET formation and downregulated key inflammatory chemokines, including CXCL1 and CXCL2, which are critical for recruiting neutrophils via the CXCR4 chemokine receptor. Enhanced signalling through CXCR4 was observed in the presence of elevated C87A, correlating with increased neutrophil infiltration and NETosis, suggesting a direct link between lipocalin-2 variants and the regulation of neutrophil activity in inflammatory conditions.Furthermore, we assessed the pathogenic role of C87A in models of obesity-induced hypertension and heart failure with preserved ejection fraction (HFpEF). Our results showed that modulation of C87A not only decreased neutrophil infiltration and NETosis but also mitigated the associated cardiovascular complications. Additionally, macrophage polarization was found to be protective against C87A-induced inflammation, while astrocytes in the brain contributed to obesity-induced hypertension through the paracrine release of inflammatory factors, including lipocalin-2.These findings highlight the complex interplay between lipocalin-2 variants, NETs, and inflammation, suggesting that targeting lipocalin-2 variant C87A may represent a novel therapeutic strategy to mitigate chronic inflammatory conditions and their cardiovascular complications. This research underscores the importance of understanding the mechanisms underlying NETs formation and the potential for lipocalin-2 variants as therapeutic targets in managing obesity-related cardiovascular diseases.

嗜中性粒细胞胞外陷阱（NETs）在应对炎症刺激的免疫反应中发挥着关键作用，但过量产生时可能导致慢性炎症。本研究探讨了NETs在感染性和无菌性炎症中的双重作用，特别是在心血管疾病背景下的作用。我们专注于脂质运载蛋白-2（LCN2）变异体——特别是多胺化脂质运载蛋白-2（hLcn2）、非多胺化脂质运载蛋白-2（C87A）和高度多胺化脂质运载蛋白-2（R81E）——与NETs形成和炎症过程之间的关联。利用转基因TG-hLcn2/LKO和全球脂质运载蛋白-2敲除（LKO）小鼠模型，我们研究了这些脂质运载蛋白-2变异体在高脂肪饮食暴露期间的表达，并评估了它们对嗜中性粒细胞寿命和表型的效应。在高脂肪饮食后，我们的研究发现C87A水平在心脏和附睾白色脂肪组织（eWAT）中显著升高。通过抗-C87A抗体的中和作用，有效地减少了NETs的形成并下调了关键的炎症趋化因子，包括CXCL1和CXCL2，这些趋化因子通过CXCR4趋化因子受体招募嗜中性粒细胞至关重要。在C87A升高的存在下观察到CXCR4信号通路增强，这与嗜中性粒细胞浸润和NETosis的增加相关，表明脂质运载蛋白-2变异体与炎症条件下嗜中性粒细胞活性的调节之间存在直接联系。此外，我们还评估了C87A在肥胖诱导的高血压和保留射血分数心力衰竭（HFpEF）模型中的致病作用。我们的结果表明，调节C87A不仅减少了嗜中性粒细胞浸润和NETosis，还减轻了相关的心血管并发症。此外，巨噬细胞的极化被发现对C87A诱导的炎症具有保护作用，而大脑中的星形胶质细胞通过旁分泌释放炎症因子，包括脂质运载蛋白-2，促进了肥胖诱导的高血压。这些发现突出了脂质运载蛋白-2变异体、NETs和炎症之间的复杂相互作用，表明针对脂质运载蛋白-2变异体C87A可能代表一种新颖的治疗策略，以减轻慢性炎症条件和其心血管并发症。本研究强调了理解NETs形成机制的重要性，以及脂质运载蛋白-2变异体作为治疗靶点在管理肥胖相关心血管疾病中的潜力。