The Effects of Nicotine and NNK on gingival fibroblast

Hwang, Chi Hoon; Park, Mi Young; Park, Kwang Kyun; Choi, Seong Ho; Cho, Kyoo Sung; Kim, Chong Kwan; Chai, Jung Kiu

Abstract

In order to observe the effects of Nicotine and NNK on cultured human gingival fibroblast, several factors were examined including mutagenicity, the number of cells attached culture plate surface through MTT test, the abundance of collagen & collagenase in mRNA level and collagenolytic activity in extracellular matrix. The results were as follows; 1. Regardless of the co-existence of S9, Nicotine did not show the mutagenicity by itself and NNK by itself showd the same result; However, dose related mutagenicity was shown in NNK with S9. 2. The number of fibroblasts attached cultured plate surface was measured by MTT procedure. The number of cells in Non-smokers increased at all time periods as compared to those of smoker. 3. Non-smoker's fibroblast treated by NNK or Nicotine was dose-dependently decreased in the number of cells when compared to untreated control. In higher dose, Nicotine showed the cellular toxicity , but NNK did not. 4. No change in the abundance of mRNA for proalpha1 and proalpha2 was shown in Nicotine treated group but in gingival fibroblasts following treatment with NNK, the abundance of mRNA for proalpha1, but not proalpha2 collagen was decreased. 5. The abundance of mRNA for collagenase was decreased when NNK was treated but no change occurred in Nicotine treated group. 6. The effect of NNK and Nicotine in collagenolytic activity showed that ,collagenase activity exclusively react to type I collagen, was increased in both group, but gelatinase exclusively react to type IV collagen was not influenced at all. Collagenase activity of smoker's fibroblast was also increased as much as Nicotine and NNK group. The findings suggest that both of Nicotine and NNK lead gingival fibroblast to decrease in the abundance of collagen. And it seems to be that Nicotine and NNK have independent pathway toward the gingival fibroblast.