Abstract：
BACKGROUND: Diabetes mellitus (DM) impairs wound healing. The aim was to determine whether DM influences mitochondrial respiration in wounded skin (WS) and non-wounded skin (NWS), in a pre-clinical wound healing model of streptozotocin (STZ)-induced diabetes.
METHODS: Six weeks after diabetes induction, two wounds were created in the back of C57BL/J6 mice. Using high-resolution respirometry (HRR), oxygen flux was measured, in WS and NWS, using two substrate-uncoupler-inhibitor titration protocols, at baseline (day 0), day 3 and 10 post-wounding, in STZ-DM and non-diabetic (NDM) mice. Flux control ratios for the oxidative phosphorylation (OXPHOS) capacity were calculated.
RESULTS: A significant increase in mitochondrial respiration was observed in STZ-DM skin compared to control skin at baseline. The OXPHOS capacity was decreased in WS under diabetes at day 3 post-wounding (inflammation phase). However, at day 10 post-wounding (remodeling phase), the OXPHOS capacity was higher in WS from STZ-DM compared to NDM mice, and compared to NWS from STZ-DM mice. A significant relative contribution of pyruvate, malate and glutamate (PMG) oxidation to the OXPHOS capacity was observed in WS compared to NWS from STZ-DM mice, at day 10, while the relative contribution of fatty acid oxidation to the OXPHOS capacity was higher in NWS. The OXPHOS capacity is altered in WS from STZ-DM compared to NDM mice across the healing process, and so is the substrate contribution in WS and NWS from STZ-DM mice, at each time point.
CONCLUSIONS: HRR may be a sensitive tool to evaluate the underlying mechanisms of tissue repair during wound healing.
METHODS: Six weeks after diabetes induction, two wounds were created in the back of C57BL/J6 mice. Using high-resolution respirometry (HRR), oxygen flux was measured, in WS and NWS, using two substrate-uncoupler-inhibitor titration protocols, at baseline (day 0), day 3 and 10 post-wounding, in STZ-DM and non-diabetic (NDM) mice. Flux control ratios for the oxidative phosphorylation (OXPHOS) capacity were calculated.
RESULTS: A significant increase in mitochondrial respiration was observed in STZ-DM skin compared to control skin at baseline. The OXPHOS capacity was decreased in WS under diabetes at day 3 post-wounding (inflammation phase). However, at day 10 post-wounding (remodeling phase), the OXPHOS capacity was higher in WS from STZ-DM compared to NDM mice, and compared to NWS from STZ-DM mice. A significant relative contribution of pyruvate, malate and glutamate (PMG) oxidation to the OXPHOS capacity was observed in WS compared to NWS from STZ-DM mice, at day 10, while the relative contribution of fatty acid oxidation to the OXPHOS capacity was higher in NWS. The OXPHOS capacity is altered in WS from STZ-DM compared to NDM mice across the healing process, and so is the substrate contribution in WS and NWS from STZ-DM mice, at each time point.
CONCLUSIONS: HRR may be a sensitive tool to evaluate the underlying mechanisms of tissue repair during wound healing.
摘要：
背景：糖尿病（DM）损害伤口愈合。目的是确定DM是否影响受伤皮肤（WS）和非受伤皮肤（NWS）的线粒体呼吸，在链脲佐菌素（STZ）诱导的糖尿病的临床前伤口愈合模型中。
方法：糖尿病诱导后6周，在C57BL/J6小鼠的背部产生两个伤口。使用高分辨率呼吸测量(HRR)，测量氧通量，在WS和NWS中，使用两种底物-解偶联剂-抑制剂滴定方案，在基线（第0天），伤后第3天和第10天,在STZ-DM和非糖尿病（NDM）小鼠中。计算氧化磷酸化(OXPHOS)能力的通量控制比。
结果：与基线时的对照皮肤相比，在STZ-DM皮肤中观察到线粒体呼吸的显着增加。在创伤后第3天（炎症期），糖尿病患者的OXPHOS能力降低。然而,在创伤后第10天（重塑阶段），与NDM小鼠相比，来自STZ-DM的WS的OXPHOS容量更高，并与来自STZ-DM小鼠的NWS进行比较。丙酮酸的显著相对贡献，与STZ-DM小鼠的NWS相比，在WS中观察到苹果酸和谷氨酸（PMG）氧化为OXPHOS能力，在第10天，而NWS中脂肪酸氧化对OXPHOS容量的相对贡献更高。在整个愈合过程中，与NDM小鼠相比，来自STZ-DM的WS的OXPHOS容量发生了变化，来自STZ-DM小鼠的WS和NWS的底物贡献也是如此，在每个时间点。
结论：HRR可能是评估伤口愈合过程中组织修复的潜在机制的敏感工具。
方法：糖尿病诱导后6周，在C57BL/J6小鼠的背部产生两个伤口。使用高分辨率呼吸测量(HRR)，测量氧通量，在WS和NWS中，使用两种底物-解偶联剂-抑制剂滴定方案，在基线（第0天），伤后第3天和第10天,在STZ-DM和非糖尿病（NDM）小鼠中。计算氧化磷酸化(OXPHOS)能力的通量控制比。
结果：与基线时的对照皮肤相比，在STZ-DM皮肤中观察到线粒体呼吸的显着增加。在创伤后第3天（炎症期），糖尿病患者的OXPHOS能力降低。然而,在创伤后第10天（重塑阶段），与NDM小鼠相比，来自STZ-DM的WS的OXPHOS容量更高，并与来自STZ-DM小鼠的NWS进行比较。丙酮酸的显著相对贡献，与STZ-DM小鼠的NWS相比，在WS中观察到苹果酸和谷氨酸（PMG）氧化为OXPHOS能力，在第10天，而NWS中脂肪酸氧化对OXPHOS容量的相对贡献更高。在整个愈合过程中，与NDM小鼠相比，来自STZ-DM的WS的OXPHOS容量发生了变化，来自STZ-DM小鼠的WS和NWS的底物贡献也是如此，在每个时间点。
结论：HRR可能是评估伤口愈合过程中组织修复的潜在机制的敏感工具。
