Conjugated Linoleic Acid (CLA) Ameliorates Hydrogen Peroxide-Induced Oxidative Stress on Rat Cardiomyoblast H9c2 Cells

Hydrogen peroxide를 처리한 rat 배아심근 H9c2 세포에서 CLA의 oxidative stress 완화 효과

Conjugated linoleic acid (CLA) exhibits several beneficial biological activities including anticarcinogenesis and body-fat reduction. Now, we report that CLA ameliorated the oxidative stress in rat cardiomyoblast cells, H9c2, treated with hydrogen peroxide ($H_2O_2$). Cells were cultured in DMEM/F-12 media at $37^{\circ}C$ with humidified atmosphere of 5% $CO_2$. The cells, cultured for 48 hrs, were seeded at a density $3.5{\times}10^3$ cell/well in a 24 well-plate and incubated for 24 hr. Using these cells, two experiments were performed: the cytotoxicity test of CLA (10, 20, 30, 40, and $50{\mu}Ms$), and the oxidative stress amelioration test of CLA (20 and $50{\mu}Ms$) against cells treated with $H_2O_2$ (10 and 50 ${\mu}Ms$) for 1 and 2 hrs. CLA enhanced the growth of H9c2 cells at any concentrations of CLA and at any incubation times (up to 6 days), indicating that CLA acts as a growth stimulant. No protective effect of CLA (20 and $50{\mu}Ms$) was seen in cells treated $50{\mu}M$ $H_2O_2$ for 1 and 2 hr, but these CLA concentrations ameliorated (p<0.05) the adverse effect of $10{\mu}M$ $H_2O_2$ in cells treated for 1 hr. These CLA concentrations significantly (p<0.05) reduced the proportion of apoptotic cells, relative to control cells. These results suggest that CLA protected H9c2 cells from the oxidative stress of $H_2O_2$ through the suppression of cell apoptosis and could be a useful compound for the prevention of cardiac diseases caused by oxidative stress.

Hydrogen peroxide ($H_2O_2$)를 처리한 rat cardiomyoblast H9c2 cell (rat 배아심근 세포)에서 conjugated linoleic acid (CLA)의 oxidative stress 경감 효과를 연구하였다. H9c2 세포는 DMEM/F-12 배지에서 배양($37^{\circ}C$, 5% $CO_2$)하였다. CLA (10, 20, 30, 40, $50{\mu}M$)는 배양 6일간 H9c2 세포 증식을 거의 직선적으로 촉진하였다. 따라서 CLA ($20{\mu}M$, $50{\mu}M$)를 H9c2 cell에 2일간 처리한 후 $H_2O_2$ ($10{\mu}M$; 각각 1시간 및 2시간 처리)의 독성을 조사한 결과 CLA ($20{\mu}M$, $50{\mu}M$)는 $10{\mu}M$ $H_2O_2$ 1시간 처리에서 세포독성을 대조에 비해 유의성 있게 억제하였다(p<0.05). 또한 이 CLA는 apoptotic DNA 분포를 대조 세포에 비해 유의성 있게 감소 시켰다(p<0.05). 따라서 이 결과는 CLA가 $H_2O_2$에 의한 apoptosis를 억제함으로서 oxidative stress로부터 H9c2 세포를 보호한다고 사료되고, 이 CLA는 cardiac diseases를 보호할 수 있는 물질로 사용될 수 있을 것이다. 그러나 많은 연구가 수행되어야 할 것이다.