Mei May L, Ito L, Cao Y, Li Q L, Chu C H, Lo Edward C M
Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region.
Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region; College of Stomatology, Anhui Medical University, Hefei, PR China.
J Dent. 2014 Mar;42(3):329-35. doi: 10.1016/j.jdent.2013.11.018. Epub 2013 Dec 4.
The expression of cysteine cathepsins in human carious dentine suggests that this enzyme contributes to the collagen degradation in caries progress. This study investigated whether silver diamine fluoride (SDF) inhibited the activity of cysteine cathepsins.
Three commercial SDF solutions with concentrations at 38%, 30% and 12% were studied. Two fluoride solutions with the same fluoride ion (F(-)) concentrations as the 38% and 12% SDF solutions, and 2 silver solutions with the same silver ion (Ag(+)) concentrations as the 38% and 12% SDF solutions were prepared. Five samples of each experimental solution were used to study their inhibitory effect on two cathepsins (B and K) using cathepsin assay kits. Positive control contained assay buffer and cathepsins dilution was used to calculate the percentage inhibition (difference between the mean readings of the test solution and control solution divided by that of the control group).
The percentage inhibition of 38%, 30% and 12% SDF on cathepsin B were 92.0%, 91.5% and 90.3%, respectively (p<0.001); on cathepsin K were 80.6%, 78.5% and 77.9%, respectively (p<0.001). Ag(+) exhibited the inhibitory effect against both cathepsin B and K with or without the presence of F(-) (p<0.01). The solutions containing Ag(+) have significantly higher inhibitory effect than the solutions containing F(-) only (p<0.01).
According to this study, SDF solution at all 3 tested concentrations significantly inhibited the activity of cathepsin B and K.
半胱氨酸组织蛋白酶在人类龋损牙本质中的表达表明，该酶在龋病进展过程中有助于胶原蛋白的降解。本研究调查了氨硝酸银（SDF）是否能抑制半胱氨酸组织蛋白酶的活性。
研究了三种浓度分别为38%、30%和12%的市售SDF溶液。制备了两种氟离子（F(-)）浓度与38%和12% SDF溶液相同的氟溶液，以及两种银离子（Ag(+)）浓度与38%和12% SDF溶液相同的银溶液。使用组织蛋白酶检测试剂盒，每种实验溶液取五个样本，研究它们对两种组织蛋白酶（B和K）的抑制作用。阳性对照包含检测缓冲液，组织蛋白酶稀释液用于计算抑制百分比（测试溶液和对照溶液的平均读数之差除以对照组的平均读数）。
38%、30%和12%的SDF对组织蛋白酶B的抑制百分比分别为92.0%、91.5%和90.3%（p<0.001）；对组织蛋白酶K的抑制百分比分别为80.6%、78.5%和77.9%（p<0.001）。无论是否存在F(-)，Ag(+)对组织蛋白酶B和K均表现出抑制作用（p<0.01）。含Ag(+)的溶液比仅含F(-)的溶液具有显著更高的抑制作用（p<0.01）。
根据本研究，所有三种测试浓度的SDF溶液均能显著抑制组织蛋白酶B和K的活性。
