Kleter G A, Damen J J, Buijs M J, Ten Cate J M
Department of Cariology-Endodontology-Pedodontology, Academic Center for Dentistry Amsterdam (ACTA), The Netherlands.
J Dent Res. 1998 Mar;77(3):488-95. doi: 10.1177/00220345980770030801.
The Maillard reaction between sugar and protein has been postulated as the cause for the browning and arrestment of caries lesions. This reaction has been implicated as the cause for decreased degradability of collagen in vivo. The aim of the present study was to verify the occurrence of the reaction in vivo. Carious and sound dentin samples were taken from extracted human teeth and analyzed for the fluorescence characteristic of the Maillard reaction and oxidation and, by HPLC, for Maillard products. In addition, physiological cross-links were analyzed by HPLC. Oxidation- and Maillard reaction-related fluorescence increased in collagenase digests from carious dentin. Advanced Maillard products (carboxymethyllysine and pentosidine) increased, whereas furosine, a marker for the initial reaction, was not observed consistently. This implies no direct addition of sugars to protein, but rather the addi-tion of smaller metabolites and glycoxidation products. In addition, the physiological cross-links hydroxylysinonorleucine and dihydroxylysinonorleucine decreased in carious dentin. Also for hydroxylysylpyridinoline, a decrease was observed, but not consistently. In conclusion, the caries process modifies amino acids in dentin collagen, which can lead to increased resistance against proteolysis and ultimately to caries arrestment.
糖与蛋白质之间的美拉德反应被认为是龋损病变褐变和停滞的原因。该反应被认为是体内胶原蛋白降解性降低的原因。本研究的目的是验证该反应在体内的发生情况。从拔除的人类牙齿中获取龋损和健康牙本质样本，分析美拉德反应的荧光特性、氧化情况，并通过高效液相色谱法分析美拉德产物。此外，通过高效液相色谱法分析生理交联。龋损牙本质的胶原酶消化物中与氧化和美拉德反应相关的荧光增加。晚期美拉德产物（羧甲基赖氨酸和戊糖苷）增加，而作为初始反应标志物的果糖胺并未始终被观察到。这意味着不是直接向蛋白质中添加糖，而是添加较小的代谢产物和糖氧化产物。此外，龋损牙本质中生理交联羟赖氨酸正亮氨酸和二羟赖氨酸正亮氨酸减少。对于羟赖氨酸吡啶啉，也观察到减少，但并不一致。总之，龋病过程会改变牙本质胶原蛋白中的氨基酸，这可能导致对蛋白水解的抵抗力增加，并最终导致龋病停滞。
