Department of Medical Genetics, University of Pécs, Clinical Center, Pécs, Hungary.
Scand J Clin Lab Invest. 2011 Jul;71(4):280-6. doi: 10.3109/00365513.2011.560674. Epub 2011 Mar 3.
Here we report the serum carnitine ester profile during and after 1g iv/day L-carnitine supplementation in haemodialysis patients.
Seven patients were studied over 29 weeks. After a control day, 12 weeks of replacement therapy was introduced followed by 17 weeks of washout period. The serum acylcarnitine concentrations were determined by isotope dilution ESI MS/MS technique.
At baseline significantly decreased free carnitine (48%, p < 0.01) and a 1.5-16-fold elevation of 16 out of 27 acylcarnitines were detected in HD patients compared with the controls. On the last day of L-carnitine supplementation a 1.6-4.8-fold increase was observed in the acylcarnitine levels compared with day 0; the increase-profile was achieved in four different patterns. The increase rate was rapid and early saturable for C5, C5OH, C6DC, C8:1, C10DC and C18:2 esters, slower for C2, C4, C6, C18 and C18:1 esters, it was slowest and reached a late plateau for C3, C8DC, C14:2, C16 and C16:1, and finally almost gradual increase was seen for 11 acylcarnitines. Three months after the cessation of carnitine treatment marked concentration drops were found for almost all acylcarnitines (by 11-74 % of week 12, p < 0.05); the values further decreased over the five remaining weeks of the observation period.
Carnitine administration affected the levels of circulating esters in different dynamics and kinetics suggesting a regulated, non-random adaptive reallocation of nutrients. A considerable washout was achieved 3 months after discontinuation of the supplementation; however, the profile still was suggestive for presence of rest of accumulated supplement.
本研究报道了血液透析患者每天静脉滴注 1g 左旋肉碱治疗期间和治疗结束后血清肉碱酯的变化。
7 名患者接受了 29 周的研究。在对照日后，进行了 12 周的替代治疗，随后是 17 周的洗脱期。采用同位素稀释 ESI MS/MS 技术测定血清酰基肉碱浓度。
与对照组相比，基线时血液透析患者游离肉碱显著降低（48%，p<0.01），27 种酰基肉碱中有 16 种升高了 1.5-16 倍。在左旋肉碱补充的最后一天，与第 0 天相比，酰基肉碱水平升高了 1.6-4.8 倍；这种增加模式呈四种不同的形态。C5、C5OH、C6DC、C8:1、C10DC 和 C18:2 酯的增加速度快且早期达到饱和，C2、C4、C6、C18 和 C18:1 酯的增加速度较慢，C3、C8DC、C14:2、C16 和 C16:1 的增加速度最慢，达到后期平台期，最后 11 种酰基肉碱几乎呈逐渐增加。肉碱治疗停止 3 个月后，几乎所有酰基肉碱的浓度都明显下降（与第 12 周相比下降 11-74%，p<0.05）；在观察期的剩余 5 周内，这些值进一步下降。
肉碱的给予以不同的动力学和时间动态影响循环酯的水平，提示存在受调节的、非随机的营养物质再分配。补充停止 3 个月后，肉碱的清除量很大，但仍提示存在部分蓄积的补充剂。
