Kato Hisayoshi, Nishida Keiichiro, Yoshida Aki, Takada Itsuro, McCown Cherie, Matsuo Masatsugu, Murakami Takuro, Inoue Hajime
Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
J Rheumatol. 2003 Feb;30(2):247-55.
To determine the effect of NOS2 gene deletion on articular cartilage degradation in autoantibody mediated arthritis (AMA).
Female C57BL/6Ai-[ko] NOS2 N5 (NOS2-/-) mice (7-8 weeks old) and the counterpart C57/Bl6 Crj mice (wild-type, WT) were studied. Arthritis was induced by intraperitoneal injection of 4 mg of an arthritogenic cocktail of 4 monoclonal antibodies raised against type II collagen twice on Day 0 and Day 1 followed by intraperitoneal injection of 50 micro g of lipopolysaccharide on Day 2. Individual limbs were scored for arthritis in 4 grades; the total maximum score per mouse was 16. Femoral condyles and tibial plateaus of both knee joints were collected on Day 15 for immunohistological studies on nitrotyrosine and matrix metalloproteinase (MMP)-3 and -9. DNA fragmentation in chondrocytes was detected by the nick-end labeling (TUNEL) method. Blood was also collected on Day 15 to determine serum levels of nitrite/nitrate and interleukin 1 beta (IL-1 beta).
Both NOS2-/- and WT mice with AMA developed clinically apparent arthritis. In WT mice, the arthritis progressed rapidly and reached the peak score 11.4 +/- 2.9 on Day 12, whereas the arthritis in NOS2-/- mice was milder and the peak score was 7.7 +/- 2.8 on Day 13 (p < 0.05). The serum nitrite/nitrate levels, histological grades of articular cartilage degradation, and numbers of apoptotic chondrocytes and nitrotyrosine positive chondrocytes were significantly lower in NOS2-/- mice with AMA than in WT mice with AMA. Conversely, significant differences were not observed in MMP-3 or -9 expression in chondrocytes, or in serum IL-1 beta levels between these 2 groups of mice.
NOS2 gene deletion did not affect the inflammatory responses, but reduced the cartilage degradation.
确定一氧化氮合酶2（NOS2）基因缺失对自身抗体介导的关节炎（AMA）中关节软骨降解的影响。
研究雌性C57BL/6Ai-[ko] NOS2 N5（NOS2-/-）小鼠（7-8周龄）及同窝对照C57/Bl6 Crj小鼠（野生型，WT）。于第0天和第1天腹腔注射4mg由4种抗II型胶原单克隆抗体组成的致关节炎混合物，第2天腹腔注射50μg脂多糖，诱导小鼠发生关节炎。对每只小鼠的各个肢体关节炎进行4级评分；每只小鼠的总分最高为16分。于第15天收集双侧膝关节的股骨髁和胫骨平台，用于硝基酪氨酸、基质金属蛋白酶（MMP）-3和-9的免疫组织学研究。采用缺口末端标记法（TUNEL）检测软骨细胞中的DNA片段化。于第15天采集血液，测定血清亚硝酸盐/硝酸盐水平和白细胞介素1β（IL-1β）水平。
患有AMA的NOS2-/-和WT小鼠均出现明显的临床关节炎。在WT小鼠中，关节炎进展迅速，在第12天达到峰值评分11.4±2.9，而NOS2-/-小鼠的关节炎较轻，在第13天达到峰值评分7.7±2.8（p<0.05）。患有AMA的NOS2-/-小鼠的血清亚硝酸盐/硝酸盐水平、关节软骨降解的组织学分级、凋亡软骨细胞和硝基酪氨酸阳性软骨细胞数量均显著低于患有AMA的WT小鼠。相反，两组小鼠软骨细胞中MMP-3或-9的表达以及血清IL-1β水平未观察到显著差异。
NOS2基因缺失不影响炎症反应，但可减少软骨降解。
