Sinan Selma, Kockar Feray, Gencer Nahit, Yildirim Hatice, Arslan Oktay
Balikesir University, Science and Art Faculty, Department of Biology/Biochemistry Section, Turkey.
Biol Pharm Bull. 2006 Aug;29(8):1559-63. doi: 10.1248/bpb.29.1559.
Paraoxonase (PON1, EC 3.1.8.1) is an esterase protein which plays multifunctional role in metabolism. Therefore, in this study the effects of commonly used antibiotics, namely sodium ampicillin, ciprofloxacin, rifamycin SV and clindamycin phosphate, on human PON1 were investigated in vitro and in vivo. Human serum paraoxonase (PON1) was separately purified by ammonium sulfate precipitation and hydrophobic interaction chromatography. The in vitro effects of the antibiotics in purifying human serum paraoxonase was determined using paraoxon as a substrate, and the IC50 values of these drugs exhibiting inhibition effects were found from graphs of hydratase activity % by plotting the concentration of the drugs. It was determined that sodium ampicillin, ciprofloxacin, and clindamycin phosphate were effective inhibitors on human serum PON1, and the inhibition kinetics of interaction of sodium ampicillin, ciprofloxacin, and clindamycin phosphate with the human serum PON1 was also determined, with the Ki of sodium ampicillin, ciprofloxacin, and clindamycin phosphate being 0.00714+/-0.00068, 6.5x10(-6)+/-4.59x10(-7), 0.0291+/-0.0077 mM, respectively. The in vivo effects of the antibiotics on paraoxonase enzyme activity in mouse serum and liver PON1 were also investigated. Mouse liver PON1 activity showed a statistically significant change at 2, 4 and 6 h of drug application in vivo. Sodium ampicillin and clindamycin phosphate exhibited about 80% mouse liver PON1 at 2 or 4 h (p: 0.034, 0.003 and 0.021, respectively). In addition, ciprofloxacin and rifamycin SV only showed inhibition at 4 h incubation. Sodium ampicillin (17.12 mg/kg) lead to a significant decrease in mouse serum PON1 after 4 h drug administration. Ciprofloxacin (3.2 mg/kg), rifamycin SV (3.56 mg/kg) and clindamycin phosphate (2.143 mg/kg) did not exhibit any inhibition effect for the mouse serum PON1, in vivo.
对氧磷酶（PON1，EC 3.1.8.1）是一种酯酶蛋白，在新陈代谢中发挥多种功能。因此，在本研究中，对常用抗生素氨苄西林钠、环丙沙星、利福霉素SV和克林霉素磷酸酯对人PON1的影响进行了体外和体内研究。人血清对氧磷酶（PON1）分别通过硫酸铵沉淀和疏水相互作用色谱法进行纯化。以对氧磷为底物测定了抗生素在纯化人血清对氧磷酶中的体外作用，并通过绘制药物浓度对水解酶活性百分比的曲线，从图表中得出显示抑制作用的这些药物的IC50值。确定氨苄西林钠、环丙沙星和克林霉素磷酸酯是人血清PON1的有效抑制剂，并测定了氨苄西林钠、环丙沙星和克林霉素磷酸酯与人血清PON1相互作用的抑制动力学，氨苄西林钠、环丙沙星和克林霉素磷酸酯的Ki分别为0.00714±0.00068、6.5×10⁻⁶±4.59×10⁻⁷、0.0291±0.0077 mM。还研究了抗生素对小鼠血清和肝脏PON1中对氧磷酶活性的体内影响。在体内给药2、4和6小时时，小鼠肝脏PON1活性显示出统计学上的显著变化。氨苄西林钠和克林霉素磷酸酯在2或4小时时对小鼠肝脏PON1的抑制率约为80%（p值分别为0.034、0.003和0.021）。此外，环丙沙星和利福霉素SV仅在孵育4小时时显示抑制作用。给药4小时后，氨苄西林钠（17.12 mg/kg）导致小鼠血清PON1显著降低。环丙沙星（3.2 mg/kg）、利福霉素SV（3.56 mg/kg）和克林霉素磷酸酯（2.143 mg/kg）在体内对小鼠血清PON1未表现出任何抑制作用。
