Candelli M, Armuzzi A, Miele L, Nista E C, Pignataro G, Zileri Dal Verme L, Grieco A, Gasbarrini G, Gasbarrini A
Internal Medicine Department, Catholic University of Rome, Italy.
Eur Rev Med Pharmacol Sci. 2007 Nov-Dec;11(6):401-6.
13C-Ketoisocaproic Acid Breath Test (13C-Kica-BT) has been proposed to assess mitochondrial function. Aim of this study is to evaluate whether gender affects mithocondrial oxidation by means of 13C-Kica-BT in healthy subjects in basal conditions and after an acute oxidative stress induced by ethanol.
50 healthy volunteers were given 1 mg/kg of 13C-Kica together with 20 mg/kg of L-leucine dissolved in 200 ml of orange juice. Breath samples were taken at baseline, every 5 minutes for 45 minutes and then every 15 minutes until 2 hours. Forty-eight hours later the test was repeated 30 min after ethanol ingestion (0.5 g/kg body weight). 13CO2 enrichment in breath was analyzed by isotope ratio/mass spectrometry. Statistical analysis was performed using the student's t test.
At baseline conditions, the percentage of Ketoisocaproic acid in 2 hours was significantly higher in females than in males. Ethanol significantly reduces the oxidation of Ketoisocaproic acid. Conversely, no differences were observed between groups after the ethanol oral load.
Decarboxylation of 13C-Kica was significantly higher in females than in males. Ethanol decreases Kica decarboxylation in particular in women. Further studies remain needed to establish whether sexual hormones could interfere with the metabolism of Kica.
13C-酮异己酸呼气试验（13C-Kica-BT）已被提议用于评估线粒体功能。本研究的目的是通过13C-Kica-BT评估在基础状态下以及乙醇诱导急性氧化应激后，性别是否会影响健康受试者的线粒体氧化。
50名健康志愿者口服1mg/kg的13C-Kica以及溶解于200ml橙汁中的20mg/kg的L-亮氨酸。在基线时采集呼气样本，之后每5分钟采集一次，共采集45分钟，然后每15分钟采集一次，直至2小时。48小时后，在摄入乙醇（0.5g/kg体重）30分钟后重复该试验。通过同位素比率/质谱分析法分析呼气中13CO2的富集情况。采用学生t检验进行统计分析。
在基线条件下，2小时内酮异己酸的百分比在女性中显著高于男性。乙醇显著降低了酮异己酸的氧化。相反，在口服乙醇负荷后，各组之间未观察到差异。
13C-Kica的脱羧在女性中显著高于男性。乙醇会降低Kica的脱羧，尤其是在女性中。仍需要进一步研究以确定性激素是否会干扰Kica的代谢。
