Dinçel Ercan, Özkan Yeşim, Şüküroğlu Murat, Özsoy Hakan, Sepici Dinçel Aylin
Department of Orthopedics and Traumatology, University of Health Sciences, Ankara Training and Research Hospital, Ankara, Turkey.
Department of Biochemistry, University of Gazi, Faculty of Pharmacy, Ankara, Turkey.
Arch Rheumatol. 2017 Mar 24;32(3):203-208. doi: 10.5606/ArchRheumatol.2017.6216. eCollection 2017 Sep.
This study aims to evaluate tryptophan degradation and clarify whether altered levels of kynurenine and tryptophan (Kyn/Trp) ratio could be correlated to osteoporotic hip fractures via immune system.
The study included 60 patients with osteoporotic hip fracture (20 males, 40 females, mean age 76.6±6.9 years; range 59 to 95 years). Patients were divided into two as patients with collum femoris fractures (group 1; n=23) and intertrochanteric fractures (group 2; n=37). Fifteen healthy subjects without any fracture were selected as control group (group 3; 3 males, 12 females; mean age 69.7±8.4; range 60 to 86 years). All fractures were simple falls due to low energy trauma. Bone mineral density measurements were performed with Lunar dual energy X-ray absorptiometry. Kyn/Trp levels were measured by high performance liquid chromatography. Interleukin (IL)-6 and IL-1 beta levels were measured with solid-phase sandwich enzyme-linked immunosorbent assay.
All bone mineral density values were in agreement for osteoporosis and there was no significant difference between the two groups. Higher Kyn/Trp ratios were observed in groups 1 and 2 compared to group 3. This difference was more significant in group 1 (p=0.0001) than that in group 2 (p=0.048). Also, group 1 had significantly higher Kyn/Trp ratio than group 2 (p=0.011). There were significantly higher IL-6 and lower IL-1 beta levels both in groups 1 and 2 compared to group 3 (p=0.0001). There was no significant difference between group 1 and group 2 in terms of IL-6 and IL-1 beta levels. There was positive correlation with Kyn/Trp ratio (r=0.581, p=0.004) in group 2. Also, significant correlation was detected between IL-6 and IL-1 beta levels in the same group (r=0.665, p=0.036).
Both increased degradation of tryptophan and ratio of Kyn/Trp indicate the relationship of immune activation with bone healing.
本研究旨在评估色氨酸降解情况，并阐明犬尿氨酸和色氨酸（Kyn/Trp）比值的改变是否可能通过免疫系统与骨质疏松性髋部骨折相关。
本研究纳入60例骨质疏松性髋部骨折患者（20例男性，40例女性，平均年龄76.6±6.9岁；年龄范围59至95岁）。患者分为两组，股骨颈骨折患者（第1组；n = 23）和转子间骨折患者（第2组；n = 37）。选择15例无骨折的健康受试者作为对照组（第3组；3例男性，12例女性；平均年龄69.7±8.4岁；年龄范围60至86岁）。所有骨折均为低能量创伤导致的简单跌倒。采用Lunar双能X线吸收法进行骨密度测量。用高效液相色谱法测量Kyn/Trp水平。用固相夹心酶联免疫吸附测定法测量白细胞介素（IL）-6和IL-1β水平。
所有骨密度值均符合骨质疏松诊断标准，两组之间无显著差异。与第3组相比，第1组和第2组观察到更高的Kyn/Trp比值。第1组的这种差异（p = 0.0001）比第2组（p = 0.048）更显著。此外，第1组的Kyn/Trp比值显著高于第2组（p = 0.011）。与第3组相比，第1组和第2组的IL-6水平显著更高，IL-1β水平更低（p = 0.0001）。第1组和第2组在IL-6和IL-1β水平方面无显著差异。第2组中Kyn/Trp比值呈正相关（r = 0.581，p = 0.004）。此外，同一组中IL-6和IL-1β水平之间检测到显著相关性（r = 0.665，p = 0.036）。
色氨酸降解增加和Kyn/Trp比值均表明免疫激活与骨愈合之间的关系。
