Langer Stefan, Beescho Christian, Ring Andrej, Dorfmann Olivia, Steinau Hans Ulrich, Spindler Nick
Department of Plastic, Esthetic and Special Hand Surgery, University Hospital Leipzig, Germany.
Department of Plastic Surgery and Severe Burns, University Hospital Bergmannsheil, Ruhr University Bochum, Germany.
GMS Interdiscip Plast Reconstr Surg DGPW. 2016 Feb 18;5:Doc09. doi: 10.3205/iprs000088. eCollection 2016.
Diabetes mellitus describes a dysregulation of glucose metabolism due to improper insulin secretion, reduced insulin efficacy or both. It is a well-known fact that diabetic patients are likely to suffer from impaired wound healing, as diabetes strongly affects tissue angiogenesis. Until now, no satisfying in vivo murine model has been established to analyze the dynamics of angiogenesis during diabetic wound healing. To help understand the pathophysiology of diabetes and its effect on angiogenesis, a novel in vivo murine model was established using the skinfold chamber in mice.
Mutant diabetic mice (db; BKS.Cg-m+/+Lepr (db) /J), wildtype mice (dock7Lepr (db) +/+m) and laboratory BALB/c mice were examined. They were kept in single cages with access to laboratory chow with an 12/12 hour day/night circle. Lesions of the panniculus muscle (Ø 2 mm) were created in the center of the transparent window chamber and the subsequent muscular wound healing was then observed for a period of 22 days. Important analytic parameters included vessel diameter, red blood cell velocity, vascular permeability, and leakage of muscle capillaries and post capillary venules. The key parameters were functional capillary density (FCD) and angiogenesis positive area (APA).
We established a model which allows high resolution in vivo imaging of functional angiogenesis in diabetic wounds. As expected, db mice showed impaired wound closure (day 22) compared to wounds of BALB/c or WT mice (day 15). FCD was lower in diabetic mice compared to WT and BALB/c during the entire observation period. The dynamics of angiogenesis also decreased in db mice, as reflected by the lowest APA levels. Significant variations in the skin buildup were observed, with the greatest skin depth in db mice. Furthermore, in db mice, the dermis:subcutaneous ratio was highly shifted towards the subcutaneous layers as opposed to WT or BALB/c mice.
Using this new in vivo model of the skinfold chamber, it was possible to analyze and quantify microangiopathical changes which are essential for a better understanding of the pathophysiology of disturbed wound healing. Research in microcirculation is important to display perfusion in wounds versus healthy tissue. Using our model, we were able to compare wound healing in diabetic and healthy mice. We were also able to objectively analyze perfusion in wound edges and compare microcirculatory parameters. This model may be well suited to augment different therapeutic options.
糖尿病是指由于胰岛素分泌不当、胰岛素效能降低或两者兼而有之导致的葡萄糖代谢失调。糖尿病患者容易出现伤口愈合受损，这是一个众所周知的事实，因为糖尿病会严重影响组织血管生成。到目前为止，尚未建立令人满意的体内小鼠模型来分析糖尿病伤口愈合过程中血管生成的动态变化。为了帮助理解糖尿病的病理生理学及其对血管生成的影响，利用小鼠皮褶箱建立了一种新型的体内小鼠模型。
对突变型糖尿病小鼠（db；BKS.Cg-m+/+Lepr(db)/J）、野生型小鼠（dock7Lepr(db)+/+m）和实验室BALB/c小鼠进行了检查。它们被饲养在单笼中，可获取实验室饲料，并处于12/12小时的昼夜循环中。在透明窗口室的中心制造腹直肌损伤（直径2mm），随后观察肌肉伤口愈合22天。重要的分析参数包括血管直径、红细胞速度、血管通透性以及肌肉毛细血管和毛细血管后微静脉的渗漏情况。关键参数是功能性毛细血管密度（FCD）和血管生成阳性面积（APA）。
我们建立了一个模型，该模型能够对糖尿病伤口中的功能性血管生成进行高分辨率的体内成像。正如预期的那样，与BALB/c或野生型小鼠的伤口（第15天）相比，db小鼠的伤口闭合受损（第22天）。在整个观察期内，糖尿病小鼠的FCD低于野生型和BALB/c小鼠。db小鼠中血管生成的动态变化也有所降低，这表现为APA水平最低。观察到皮肤结构有显著差异，db小鼠的皮肤深度最大。此外，与野生型或BALB/c小鼠相比，db小鼠的真皮与皮下组织比例明显向皮下层偏移。
利用这种新的皮褶箱体内模型，可以分析和量化微血管病变变化，这对于更好地理解伤口愈合障碍的病理生理学至关重要。微循环研究对于显示伤口与健康组织中的灌注情况很重要。利用我们的模型，我们能够比较糖尿病小鼠和健康小鼠的伤口愈合情况。我们还能够客观地分析伤口边缘的灌注情况并比较微循环参数。该模型可能非常适合增加不同的治疗选择。
