一氧化氮合酶抑制剂对骨关节炎的潜在治疗意义

目的探讨一氧化氮合酶(NOS)抑制剂L-N6-亚氨乙基-赖氨酸(L-NIL)和S-甲基异硫脲(SMT)对骨性关节炎(OA)软骨和滑膜代谢的影响,为NOS抑制剂的临床应用提供理论依据。方法无菌条件下,取17例OA患者关节软骨和滑膜,置入体外培养系统,随机分为(1)对照组:不加药物干预;(2)L-NIL组:加入NOS抑制剂L-NIL干预;(3)SMT组:加入iNOS抑制剂SMT干预。培养72h后,通过检测硝酸盐和亚硝酸盐的含量来观察软骨NO的释放量以及NOS的活性;原位杂交检测软骨iNOSmRNA和MMP9mRNA的表达。培养10d后,化学比色法观察软骨蛋白多糖含量和羟脯氨酸释放量的变化。结果对照组软骨和滑膜培养72h后,在其上清液中均可检测到高浓度NO和高活性NOS。其中软骨NO释放量和NOS活性明显高于滑膜NO释放量和NOS活性(P<0.05);原位杂交也检测到软骨iNOSmRNA和MMP9mRNA的高表达。L-NIL组和SMT组软骨和滑膜NO释放量较对照组明显减少,NOS活性明显降低(P<0.01);而L-NIL组和SMT组NO释放量和NOS活性之间的差异无显著性意义(P>0.05)。同时,未检测到iNOSmRNA和MMP9mRNA表达。培养10d后,L-NIL和SMT组OA软骨蛋白多糖的含量比对照组明显增加(F=86.3,P<0.01),羟脯氨酸释放量比对照组显著减少(F=38.1,P<0.01)。结论NOS抑制剂L-NIL和SMT能抑制过量NO的释放,改善软骨代谢环境

Potential clinical evaluation of nitric oxide synthase inhibitor for the treatment of osteoarthritis

Objective To discuss the metabolic effects on o steoarthritis cartilage by NOS inhi bitor L -N 6 -(sub -amonion -ethyl)lysine(L -NIL)and S -methylisothiourea(SMT ).Methods Seventeen specimens of articular cartilage ta ken from the patients with osteoarth rosis were placed in culture system a nd divided in three groups.The control group was not interfered with any dru g.L -NIL and SMT groups were interfered with NOS inhibitor L -NIL and SMT respectively.After 72h culture,the release of NO and the activity of NOS on osteoarthritis ca rtilage were measured by Griess reac tion and spectrophotometric method s.iNOSmRNA and MMP 9 expression was measured by in situ hybridization.Proteoglycan and hydr oxyproline in OA cartilage was measured with colorimetric analysis after 10d culture.Results After 72h cultivation,spectrophotometric analysis showe d high concentration NO release and h igh active NOS in supernates of the control,and hybridization stainin g demonstrated high iNOSmRNA and MMP 9 mRNA expression in cartilages of the control.1mmol /L concentration L -NIL and SMT evidently reduce NO release and NOS activity(P<0.05),and inhibited completely iNOSmRNA and MMP 9 mRNA expression.After 10d cultivation,colorimetric analysis revealed proteoglycan con tents in OA cartilages of L -NIL and SM T groups were significantly more than untreated group(F=86.3,P<0.01).And hydroxyproline release was markedly less in L -NIL and SMT group than OA cartilage untreate d with drugs(F=38.1,P<0.01).Conclusion NOS inhibitors reduce NO release and meliorate meta bolism of articular cartilages,whi ch could protect cartilage.[