Blomster Hillevi, Puustjärvi Tuomo, Kontkanen Matti, Valtonen Pirjo, Teräsvirta Markku, Uusitalo Hannu
Eye Policlinic, Institution of Deacony, Sibeliuksenkatu 6 C, 15110 Lahti, Finland.
Graefes Arch Clin Exp Ophthalmol. 2007 Feb;245(2):204-9. doi: 10.1007/s00417-006-0425-0.
Hyperhomocysteinemia (HH), oxidative stress and endothelial dysfunction are all implicated as possible pathogenetic factors in exfoliation syndrome (XFS) and exfoliative glaucoma (XFG). Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide and plasma level of ADMA is often elevated in HH. Thus the present study was undertaken to study plasma levels of ADMA with concomitant measurement of symmetric dimethylarginine (SDMA) and L-arginine (L-Arg) in XFS and XFG.
This cross-sectional, prospective study involved 36 XFS patients, 11 of them having XFG, and 36 age- and gender-matched controls. Fasting plasma ADMA, SDMA and L-Arg levels of participants were determined. A special view was created how plasma L-Arg, ADMA and SDMA correlate to plasma homocysteine (P-Hcy). In addition, the influence of P-Hey values derived from our previous study on the above mentioned parameters were evaluated by cut-off values of P-Hcy, 12 micromol/l for women and 14.5 micromol/l for men. RESULTS The mean plasma ADMA, SDMA and L-Arg levels were 0.41, 0.49 and 62.9 micromol/l in the XFS/XFG group, and 0.41, 0.44 and 69.7 micromol/l in the control group, respectively. As all parameters within the XFS and control group were compared, no statistical significance was stated. On the other hand, a positive correlation was observed between plasma SDMA and P-Hcy in XFGs (P = 0.002), and additionally, also a statistically significant difference was in plasma SDMA between the two groups sorted by cut-off levels of P-Hcy 0.49 +/- 0.15 vs. 0.36 +/- 0.04 micromol/l, above and below cut-off levels, respectively (P = 0.001), but not between ADMA in a respective assay. The mean values of L-Arg were 64.6 +/- 17.2 vs. 74.8 +/- 13.3 microg/l, respectively (P = 0.031). In the XFS subgroup, on the contrary, there was no positive correlation between P-Hcy and plasma SDMA.
A positive correlation of plasma SDMA in respect to P-Hcy in XFGs and increase of SDMA in mild or intermediate hyperhomocysteinemia may indicate SDMA as a marker of developing XFG in hyperhomocysteinemic
高同型半胱氨酸血症（HH）、氧化应激和内皮功能障碍均被认为是剥脱综合征（XFS）和剥脱性青光眼（XFG）可能的发病因素。不对称二甲基精氨酸（ADMA）是内皮型一氧化氮的内源性抑制剂，HH患者血浆中ADMA水平常升高。因此，本研究旨在检测XFS和XFG患者血浆中ADMA水平，并同时测定对称二甲基精氨酸（SDMA）和L-精氨酸（L-Arg）水平。
本横断面、前瞻性研究纳入了36例XFS患者，其中11例患有XFG，以及36例年龄和性别匹配的对照者。测定参与者空腹血浆中ADMA、SDMA和L-Arg水平。特别观察了血浆L-Arg、ADMA和SDMA与血浆同型半胱氨酸（P-Hcy）之间的相关性。此外，根据我们之前研究得出的P-Hcy临界值（女性为12 μmol/l，男性为14.5 μmol/l），评估P-Hcy值对上述参数的影响。结果：XFS/XFG组血浆ADMA、SDMA和L-Arg的平均水平分别为0.41、0.49和62.9 μmol/l，对照组分别为0.41、0.44和69.7 μmol/l。比较XFS组和对照组的所有参数，未发现统计学意义。另一方面，在XFG患者中观察到血浆SDMA与P-Hcy呈正相关（P = 0.002），此外，根据P-Hcy临界值将两组分类后，血浆SDMA也存在统计学显著差异（分别为高于和低于临界值，0.49±0.15与0.36±0.04 μmol/l，P = 0.001），但在各自检测中ADMA之间无差异。L-Arg的平均值分别为64.6±17.2与74.8±13.3 μg/l（P = 0.031）。相反，在XFS亚组中，P-Hcy与血浆SDMA之间无正相关。
XFG患者血浆SDMA与P-Hcy呈正相关，且在轻度或中度高同型半胱氨酸血症中SDMA升高，这可能表明SDMA是高同型半胱氨酸血症中XFG发生发展的一个标志物。
