Peran Vitamin C pada viabilitas keratinosit dan Sel HeLa yang dipajan sinar UVB

ANDAMARI, Iryani, dr. Fajar Waskito, M.Kes.,SpKK(K)

2004 | Tesis | PPDS I Ilmu Penyakit Kulit dan Kelamin

Sinar Ultraviolet B (UVB) merupakan salah satu faktor eksternal yang mampu menurunkan viabilitas sel melalui reaksi fotokimia. Hal ini dapat dikendalikan dengan antioksidan. Kegagalan pemulihan DNA dan apoptosis berperan penting pada terjadinya fotokarsinogenesis. Penelitian ini bertujuan untuk melihat efek pemberian vitamin C terhadap viabilitas keratinosit normal dan sel HeLa yang dipajan sinar UVB. Rancangan penelitian ini menggunakan metode eksperimental sederhana. Dua kelompok sel yang digunakan yaitu: Kelompok I yang terdiri dari keratinosit normal pasase-III, dan Kelompok II yang tersusun oleh sel HeLa. Tiap kelompok dibagi menjadi 25 sub-kelompok, masing-masing terdiri dari 2x104 sel, diberi vitamin C: 0, 6, 12, 40, 200 μg/ml dan dipajanan UVB: 0, 200, 400, 800, 1600 mJ/cm2 (Phillips UVB TL40W/12RS). Perlakuan secara kuintet (5x). Sel viabel dinilai berdasarkan reaksi formazan blue dengan menggunakan ELISA-reader 550 nm 24 jam pasca perlakuan. Hasil penelitian diuji dengan uji t, ANOVA satu jalan, dan ANOVA tiga jalan. C dengan konsentrasi 6, 12, 40, dan 200 μg/ml meningkatkan viabilitas keratinosit normal dan sel HeLa yang tidak dipajan UVB, bermakna secara statistik, dibanding keratinosit normal dan sel HeLa tanpa pemberian vitamin C. Sel HeLa yang dipajan UVB 200, 400, 800, dan 1600 mJ/cm2, dengan pemberian vitamin C 6, 12, 40, dan 200 μg/ml secara statistik bermakna menurunkan viabilitas sel. Pada penelitian ini dapat disimpulkan bahwa Vitamin C 200 μg/ml yang diberikan pada keratinosit normal yang dipajan UVB dengan intensitas 200, 400, 800, dan 1600 mj/cm2 memberikan efek proteksi dan meningkatkan viabilitas sel. Vitamin C 6, 12, 40 μg/ml yang dipajan UVB dengan intensitas 200, 400, 800, dan 1600 mJ/cm2 tidak memberikan efek proteksi. Sel HeLa tidak lebih resisten daripada keratinosit normal terhadap pajanan UVB pada intensitas 200, 400, 800, dan 1600 mj/cm2

Ultraviolet B (UVB) exposure is one of external factors which can cause reduction of cell viabillity through photochemistry reaction and can be managed using antioxidant. Failures of DNA repair and apoptosis have some important roles in photocarcinogenesis. This research is aimed to identify the effect of vitamin C on the viability of UVB irradiated keratinocytes and HeLa cells. This research employs a simple experimental method. Two groups of cells used in this research are: Group I which consists of normal foreskin keratinocytes passage III, and Group II containing HeLa cells. Each group is divided into 25 sub-groups consisting of 2x104 cells each, treated with vitamin C at 0, 6, 12, 40, 200 μg/ml concentrations, and UVB irradiated (Phillips UVB TL40W/12RS) at 0, 200, 400, 800, 1600 mJ/cm2 intensities. Each treatment is done on quintet. Viable cells are determined based on formazan blue reaction using ELISA-reader 550 nm 24 hours after treatment. The results are examined by independent t-test, one-way ANOVA, and multivariate analysis using three-way analysis of variance. Vitamin C at 6, 12, 40, and 200 μg/ml concentrations significantly increased normal keratinocyte and HeLa cells viability which were not irradiated by UVB, statistically significant, compared to normal keratinocyte and HeLa cells which were not treated with vitamin C. HeLa cells, which were irradiated by UVB at 200, 400, and 800, 1600 mJ/cm2 intensities and treated with vitamin C at 6, 12, 40 and 200 μg/ml concentrations, statistically significant in decreasing cell viability. It is concluded that vitamin C at 200 μg/ml concentration, which was given to normal keratinocytes irradiated to UVB at 200, 400, 800, and 1600 mj/cm2 intensities used in this research shows its protection effect, thus enhancing the viability of the cell. Vitamin C 6, 12, 40 μg/ml which were irradiated with UVB at 200, 400, 800, and 1600 mJ/cm2 intensities do not show protection effect. HeLa cells are less resistant than normal keratinocytes to UVB irradiation at 200, 400, 800, and 1600 mj/cm2 intensities.

Kata Kunci : Kulit,Viabilitas Keratinosit,Sinar UVB,Vitamin C