RESUMO
AIM:To investigate the effects of dehydroepiandrosterone(DHEA)on the expression of intercellu-lar adhesion molecule-1(ICAM-1)induced by high lipid levels in rabbit aorta and human umbilical venous endothelial cells(HUVECs),and the effects of all-trans retinoic acid(ATRA)in this process.METHODS: For in vitro experi-ments,the cultured HUVEC were divided into control group,oxidized low-density lipoprotein(ox-LDL)group,ox-LDL+DHEA group,ox-LDL+DHEA+ATRA group and DHEA group.The HUVECs in all groups were treated with the corre-sponding reagents for 24 h.The expression of ICAM-1 at mRNA and protein levels in all groups were determined by RT-PCR and ELISA,respectively.For in vivo experiments,the rabbits were divided into control group,high lipid group,high lipid+DHEA group,high lipid+DHEA+ATRA group and DHEA group.The rabbits in all groups were fed with the cor-responding diets for 10 weeks.The expression of ICAM-1 in the rabbit aorta at mRNA and protein levels was determined by RT-PCR and immunohistochemistry.RESULTS:The expression of ICAM-1 in the HUVECs in ox-LDL group was signifi-cantly increased compared with control group(P<0.05).Compared with ox-LDL group,the expression of ICAM-1 in ox-LDL+DHEA group was obviously decreased(P<0.05).The expression of ICAM-1 was similar in both control group and DHEA group(P>0.05).The expression of ICAM-1 was similar in both ox-LDL+DHEA group and ox-LDL+DHEA+ATRA group(P>0.05).The expression of ICAM-1 in the rabbit aorta in high lipid group was significantly increased com-pared with control group(P<0.05).Compared with high lipid group, the expression of ICAM-1 in high lipid+DHEA group was obviously decreased(P<0.05).No remarkable difference in the expression of ICAM-1 between control group and DHEA group was observed(P>0.05), so did between high lipid +DHEA group and high lipid +DHEA+ATRA group(P>0.05).CONCLUSION:DHEA inhibits high lipid-induced ICAM-1 expression in rabbit aorta and HUVECs. That may be one of the mechanisms of antiatherosclerotic effect of DHEA.ATRA seems no positive effect on DHEA func-tion.
RESUMO
Objective To study the effects of peroxisome prolifterator-activated receptor gamma (PPARγ) agonist on the expression of ICAM-1 mRNA in the ischemia-reperfusion brain tissues. Methods Adult male SD rats were randomly divided into: sham-operation + normal saline group (NS,n = 6 ), ischemia-reperfusion tion. The expression of ICAM-1mRNA was measured by RT-PCR at 24 h after ischemia. Results The expression of ICAM-1 mRNA of the low-dose PGZ group (0.571±0.032) and the high-dose PGZ group (0. 396±0.024)were significantly reduced compared with that of the I/R + NS group (0.847±0. 028 ) (P<0.05).Conclusion PPARγ agonists can downregulate the the expression of ICAM-1mRNA in the ischemia brain tissue.
