12(S)-HpETE/TRPV1 interaction mediates hyperglycemia-induced endothelial dysfunction: Novel approaches to early diagnosis and therapy of vascular pathology in diabetes mellitus

糖尿病影响了9%的德国人口。糖尿病导致血管疾病，糖尿病患者在接受手术和麻醉时患不良心血管并发症的风险增加。然而，目前还没有生物标志物可以通过反映先前存在的血管病变程度来对糖尿病患者进行术前风险分层。内皮功能障碍是糖尿病血管病变的先兆，也是糖尿病血管病变的主要原因。它的特点是内皮依赖性血管扩张功能降低，并伴随着内皮细胞线粒体功能障碍和线粒体钙超载。在斯坦福大学医学院研究期间，我发现糖尿病大鼠血浆中花生四烯酸代谢物12(S)-羟基过氧二十碳四烯酸(12(S)-HpETE)浓度升高。12(S)-HpETE是瞬时受体电位香草素1(TRPV1)的内源性激活剂，TRPV1是一种离子通道，主要门控钙离子I，在以前未知的定位，即在内皮细胞线粒体。在我的初步研究中，与辣椒素或高糖(25 MM)激活TRPV1相比，12(S)-HpETE激活TRPV1可诱导内皮细胞线粒体钙内流和线粒体功能障碍。12(S)-HpETE的这些作用在与12(S)-HpETE/TRPV1相互作用位点相对应的多肽诱骗(V1-cal)的存在下被取消。我的假设是，高糖导致内皮细胞产生的12(S)-HpETE浓度升高，通过诱导TRPV1介导的线粒体功能障碍来介导糖尿病的内皮功能障碍。基于这一机制，我旨在确定12(S)-HpETE可以作为一种生物标志物来识别血糖控制不良和早期血管疾病的患者。通过确定12(S)-HpETE/TRPV1相互作用位点，我的目标是在体外建立一个能抵抗高糖不利影响的内皮细胞系，并在体内使用V1-CAL逆转糖尿病引起的内皮功能障碍。最终，对于这项建议，我的长期目标是建立一种新的诊断和治疗策略，以降低糖尿病患者围手术期的风险和并发症的发生率。

Diabetes mellitus affects 9% of the German population. Diabetes mellitus leads to vascular disease and patients with diabetes mellitus have an increased risk to suffer from adverse cardiovascular complications when undergoing surgery and anesthesia. However, there is currently no biomarker that allows for preoperative risk stratification of diabetic patients by reflecting the degree of preexisting vascular pathology. Endothelial dysfunction precedes and essentially contributes to diabetes mellitus-induced vascular pathology. It is characterized by reduced endothelium-dependent vasodilation associated with mitochondrial dysfunction and mitochondrial calcium overload in endothelial cells. During my research stay at Stanford University Medical School, I found increased plasma concentrations of the arachidonic acid metabolite 12(S)-hydroperoxyeicosatetraenoic acid (12(S)-HpETE) in diabetic rats. 12(S)-HpETE is an endogenous activator of the transient receptor potential vanilloid 1 (TRPV1), an ion channel primarily gating calcium I identified at a previously unrecognized localization, namely at endothelial cell mitochondria. In my preliminary studies, activation of TRPV1 with 12(S)-HpETE induced mitochondrial calcium influx and mitochondrial dysfunction in endothelial cells comparably to TRPV1 activation by capsaicin or high levels of glucose (25mM). These effects of 12(S)-HpETE were abolished in the presence of a peptide decoy (V1-cal) corresponding to the putative 12(S)-HpETE/TRPV1 interaction site at TRPV1. My hypothesis is, that increased 12(S)-HpETE concentrations generated in endothelial cells in response to high glucose concentrations mediate endothelial dysfunction in diabetes mellitus by inducing TRPV1-mediated mitochondrial dysfunction. Based on this mechanism, I aim to identify 12(S)-HpETE can serve as a biomarker to identify patients with poor glucose control and early stage vascular disease. By identifying the 12(S)-HpETE/TRPV1 interaction site, I aim to generate an endothelial cell line resistant to the detrimental effects of high glucose concentrations in vitro and reverse diabetes mellitus-induced endothelial dysfunction using V1-cal in a mouse model in vivo. Ultimately, for this proposal my long-term goal is to establish a new diagnostic and therapeutic strategy to lower perioperative risk and the incidence of co-morbidities in patients with diabetes mellitus.