Browsing by Author "Cheng, TM"

Now showing 1 - 2 of 2

Epidemiology of haptoglobin phenotypes in chronic diseases
(2003-03-17)
Cheng, TM
;
Pan, JP
;
Wang, JS
;
Mao, SJT
;
生物科技學系
Vitamin C protects against lysophosphatidylcholine-induced expression of monocyte chemoattractant protein-1 in cultured human umbilical vein endothelial cells
(2003-03-01)
Pan, JP
;
Cheng, TM
;
Chou, SC
;
Lai, ST
;
生物科技學系
Background and Purpose: It is well documented that oxidized low-density lipoproteins (LDLs) can stimulate human vascular endothelial cells to produce monocyte chemoattractant protein-I (MCP-I). Vitamin c is known to be an important antioxidant for vasodilation. The purpose of this study was to determine whether pretreatment with vitamin could protect against oxidized LDL induced expression of MCP-1 in cultured human umbilical vein endothelial cells (HUVECs). Methods: Cultured HUVECs were used for desired experiments before passage 4. Lysophosphatidylcholine (lyso PC), an oxidized components of LDL, was designated as the stimulator for MPC-1 synthesis from cultured HUVECs MCP-1 concentration in the cultured media were determined by enzyme-linked immunosorbent assay MCP-1 RNA was evaluated by a semi quantitative reverse transcriptase-polymerase chain reaction. Results: HUVECs secreted MCP-1 within 30 minutes after exposure to 50 muM lysoPC. Compared with samples treated with lyso PC alone, pretreatment with vitamin C in concentration of 50, 100, 150 and 200 muM. reduced levels of MCP-1 in the culture medium by 44%, 51%, 60% and 67%, respectively, while levels of MCP-1 mRNA decreased by 15%, 18%, 80% and 82%, respectively. Conclusions: Our findings imply that pretreatment with vitamin C can suppress lysoPC induced expression and secretion of MCP-1 in cultured HUVECs. Therefore, vitamin C is protective against lyso mediated inflammatory insults to the vascular endothelium in vitro.