■ The Goal of Reasearch
The purposes of this research are 1) to establish a gene screening system for cardiac side effects through confirmation about developed marker gene for cardiotoxicity; 2) to establish the database for the cardiotoxicity of th...
■ The Goal of Reasearch
The purposes of this research are 1) to establish a gene screening system for cardiac side effects through confirmation about developed marker gene for cardiotoxicity; 2) to establish the database for the cardiotoxicity of the various prescription drugs using Gadd45β as a screening system ; 3) to evaluate the possibility of clinical application of the developed marker gene, Gadd45β, for cardiotoxicity.
■ Contents of Research
1) Validation of Gadd45β as a marker for cardiotoxicity and establishment of screening system for cardiac side effect
- Investigation of the correlation between the cardiotoxicity and the gene expression of Gadd45β for various drugs possessing well-known cardiac side effects
2) Establishment of the database for the cardiotoxicity of the drugs using Gadd45β as a screening system
- Examination of the expression level of cardiotoxicity marker gene, Gadd45β, for the various drugs and extablishment of the database of them
3) Evaluation of the possibility of clinical application of the developed marker for cardiotoxicity.
- Investigation of the expression of Gadd45β in blood cells from animals and patients of ischemic heart disease and in blood cell lines exposed to hypoxia
■ Research Results
1) When we examined cardiomyocyte toxicity for 13 drugs possessing well-known cardiac side effects, cardiomyocyte toxicity was revealed in 8 drugs among them, and mRNA expression of Gadd45β was increased by 7 drugs among these 8 drugs, indicating a good correlation between the cardiotoxicity and the gene expression of Gadd45β.
2) Among 13 drugs possessing well-known cardiac side effects, 5 drugs neither show any cytotoxicity in cardiac cells, nor increase the expression of Gadd45β mRNA.
3) When we exanmined cardiomyocyte toxicity for 15 prescription drugs, 5 of 15 drugs induced cardiomyocyte toxicity, and 4 drugs of 5 increased the expression of Gadd45β mRNA.
4) Among 15 precription drugs, 10 drugs neither show any cytotoxicity in cardiac cells, nor increase the expression of Gadd45β mRNA.
5) The expression of Gadd45β mRNA was not increased in blood cells from neither animals, patients of ischemic heart disease, nor in blood cell lines exposed to hypoxia.
➡ In conclusion, a screening system for cardiotoxicity was extablished using Gadd45β as a marker, indicating that the increase in the Gadd45β mRNA level reflects cardiotoxicity in cardiomyocytes. However, it should be stressed that the screening system using Gadd45β can not reflect all kinds of cardiotoxicity, for example, some drugs producing cardiotoxicity independently of Gadd45β can not be screened by this screening system using Gadd45β.