毒理性
细链霉素可逆地通过竞争丙酮酸的结合位点来抑制丙酮酸脱氢酶和α-酮戊二酸脱氢酶。这通过阻止必要的丙酮酸并入和α-酮戊二酸中间体的氧化,干扰了三羧酸循环。细链霉素还通过抑制转酮醇酶和醛糖还原酶来干扰碳水化合物代谢。
细链霉素会导致人类软骨中的软骨细胞坏死。它通过增加基质分解酶(如MMP-1和MMP-13)的表达,减少如硫酸软骨素和II型胶原等细胞外基质成分的合成来实现这一点。这加速了关节软骨中细胞外基质的分解代谢,导致软骨功能丧失,最终导致软骨降解。细链霉素还已知能引起DNA损伤,诱导染色单体断裂、染色体断裂和染色单体交换。(A3075, A3076, A3077)
Moniliformin reversibly inhibits the enzymes pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase by competing for the binding site of pyruvate. This interferes with the tricarboxylic acid cycle by preventing the necessary incorporation of pyruvate and oxidation of the alpha-ketoglutarate intermediate. Moniliformin has also been shown to interfere with carbohydrate metabolism by inhibiting transketolase and aldose reductase.
Moniliformin causes the necrosis of human chondrocytes in cartilage. It does so by increasing the expression of matrix catabolic enzymes, such as MMP-1 and MMP-13, and decreasing the syntheses of extracellular matrix components such as aggrecan and type II collage. This accelerates the catabolism of the extracellular matrix in articular cartilages, inducing a loss of cartilage function and eventually leading to cartilage degradation. Moniliformin is also known to cause DNA damage, inducing chromatid breaks, chromosome breaks, and chromatid exchanges. (A3075, A3076, A3077)
来源:Toxin and Toxin Target Database (T3DB)