Effects of Selective Estrogen Receptor Modulator Raloxifene Plus 17-beta Estradiol in Aorta and Mammary Gland of Female Experimental Atherosclerosis Rabbits and Possible Involvement of ERK Signal Tran

Qiu-Ling Xiang；Yu Chen；Gui-Ping Lin；Zhi Tan；Ting-Huai Wang

SERM ； raloxifene ； 17-βE2 ； atherosclerosis ； mammary gland ； VSMC ； ERK

The Chinese Journal of Physiology

49卷3期（2006 / 06 / 30）

132 - 140

英文

The present study investigated the effects of raloxifene, a second generation selective estrogen receptor modulator (SERM), plus 17-βE2 on aortic atherosclerosis and mammary gland hyperplasia in ovariectomized, cholesterol-fed rabbits. Following 10 weeks of raloxifene, 17-βE2, or raloxifene plus 17βE2 administration, serum total cholesterol, triglyceride, low density lipoprotein were significantly decreased in the drug groups compared to the placebo group. Consistent with serum lipid results, the total lesion area for each aorta of the drug groups decreased significantly as compared to the placebo group. HE staining of aorta paraffin section showed that in the drug groups the endothelial monolayer was almost continuous. While in mammary gland, HE staining of paraffin sections indicated the hyperplasia of epithelial cells (in 17-βE2 group) was obviously inhibited in raloxifene plus 17-βE2 group. In cultured vascular smooth muscle cell (VSMC), the results of MTT and [3H] TdR incorporation showed that the drug groups could inhibit AngⅡ-induced proliferation of VSMC. Western blotting proved that raloxifene plus 17-βE2 inhibited the expression of phosphorylated ERK protein, similar to 17-βE2 but different from raloxifene. This effect was inhibited by PD98059 (inhibitor of MAPK) or ICI182780 (ER antagonist). In conclusion, this study suggests that SERM raloxifene plus 17-βE2 improves the lipid metabolism and relieves the aorta changes of female experimental atherosclerosis rabbits, which are partly implemented by the inhibition of VSMC growth through ERK cascade. The hyperplasia of mammary gland epithelial cells could be significantly inhibited by raloxifene plus 17-βE2.

1. Aubuchon, M.,Santoro, N.(2004).Lessons learned from the WHI: HRT requires a cautious and individualized approach..Geriatrics,59,22-26.
2. Barrett-Connor, E.,Grady, D.,Sashegyi, A.,Anderson, P.W.,Cox, D.A.,Hoszowski, K.,Rautaharju, P.,Harper, K.D.(2002).MORE Investigators (Multiple Outcomes of Raloxifene Evaluation). Raloxifene and cardiovascular events in osteoporotic postmenopausal women: four-year results from the MORE (Multiple Outcomes of Raloxifene Evaluation) randomized trial..JAMA,287,847-857.
3. Bergkvist, L.,Adami, H.O.,Persson, I.,Hoover, R.,Schairer, C.(1989).The risk of breast cancer after estrogen and estrogen-progestin replacement.N. Engl. J. Med.,321,293-297.
4. Bryant, H.U.,Dere W.H.(1998).Selective estrogen receptor modulators: an alternative to hormone replacement therapy.Proc. Soc. Exp. Biol. Med.,217,45-52.
5. Castellot, J.J.,Favreau, L.V.,Karnovsky, M.J.,Rosenberg, R.D.(1982).Inhibition of vascular smooth muscle cell growth by endothelial cell-derived heparin. Possible role of a platelet endoglycosidase..J. Biol. Chem.,257,11256-11260.
6. Cuzick, J.,Powles, T.,Veronesi, U.,Forbes, J.,Edwards, R.,Ashley, S.,Boyle, P.(2003).Overview of the main outcomes in breast-cancer prevention trials.Lancet,361,296-300.
7. Davis, S.R.,Dinatale, I.,Rivera-Woll, L.,Davison, S.(2005).Postmenopausal hormone therapy: from monkey glands to transdermal patches.J. Endocrinol,185,207-222.
8. Delmas, P.D.,Bjarnason, N.H.,Mitlak, B.H.,Ravoux, A.C.,Shah, A.S.,Huster, W.J.,Draper, M.,Christiansen, C.(1997).Effects of raloxifene on bone mineral density, serum cholesterol concentrations, and uterine endometrium in postmenopausal women.N. Engl. J. Med.,337,1641-1647.
9. Eguchi, S.,Matsumoto, T.,Motley, E.D.,Utsunomiya, H.,Inagami, T.(1996).Identification of an essential signaling cascade for mitogen-activated protein kinase activation by angiotensin II in cultured rat vascular smooth muscle cells. Possible requirement of Gq-mediated p21 ras activation coupled to a Ca(superscript 2+) /calmodulin-sensitive tyrosine kinase.J. Biol. Chem,271,14169-14175.
10. Farish, E.,Spowart, K.,Barnes, J.F.,Fletcher, C.D.,Calder, A.,Brown, A.,Hart, P.M.(1996).Effects of postmenopausal hormone replacement therapy on lipoproteins including lipoprotein(a) and LDL subfractions.Atherosclerosis,126,77-84.
11. Ferrari, M.,Fornasiero, M.C.,Isetta, A.M.(1990).MTT colorimetric assay for testing macrophage cytotoxic activity in vitro.J. Immunol. Methods,131,165-172.
12. Hodis, H.N.,Mack, W.J.,Lobo, R.A.,Shoupe, D.,Sevanian, A.,Mahrer, P.R.,Selzer, R.H.,Liu, C.R.,Liu, C.H.,Azen, S.P.(2001).Estrogen in the Prevention of Atherosclerosis Trial Research Group. Estrogen in the prevention of atherosclerosis. A randomized, double-blind, placebo-controlled trial.Ann. Intern. Med.,135,939-953.
13. Hulley, S.,Grady, D.,Bush, T.,Furberg, C.,Herrington, D.,Riggs, B.,Vittinghoff, E.(1998).Randomized trial of estrogen plus progestin for secondary prevention of coronary heart disease in postmenopausal women. Heart and Estrogen/progestin Replacement Study (HERS) Research Group..JAMA,280,605-613.
14. Kannel, W.B.,Hjortland, M.C.,McNamara, P.M.,Gordon, T.(1976).Menopause and the risk of cardiovascular disease: the Framingham study.Ann. Intern. Med.,85,447-452.
15. Ke, H.Z.,Chen, H.K.,Simmons, H.A.,Qi, H.,Crawford, D.T.,Pirie, C.M.,Chidsey-Frink, K.L.,Ma, Y.F.,Jee, W.S.,Thompson, D.D.(1997).Comparative effects of droloxifene, tamoxifen and estrogen on bone, serum cholesterol, and uterine histology in ovariectomized rat model..Bone,20,31-39.
16. Landenpara, S.,Puolakka, J.,Pyorola, T.,Luotola, H.,Taskinen, M.R.(1996).Effects of postmenopausal estrogen/progestin replacement therapy on LDL particles; comparison of transdermal and oral treatment regimens.Atherosclerosis,122,153-162.
17. Mariani, A.,Sebo, T.J.,Katzmann, J.A.,Riehle, D.L.,Dowdy, S.C.,Keeney, G.L.,Lesnick, T.G.,Podratz, K.C.(2005).HER-2/neu overexpression and hormone dependency in endometrial cancer: analysis of cohort and review of literature.Anticancer Res.,25,2921-2927.
18. Mendelsohn, M.E.,Karas, R.H.(1999).The protective effects of estrogen on the cardiovascular system.N. Engl. J. Med,340,1801-1811.
19. Miller, V.T.,Muesing, R.A.,LaRosa, J.C.,Stoy, D.B.,Phillips, E.A.,Stilman, R.J.(1991).Effects of conjugated equine estrogen with and without three different progestogens on lipoproteins, high-density lipoprotein subfractions and apolipoprotein A- I..Obstet. Gynecol.,77,235-240.
20. Mitlak, B.H.,Cohen, F.J.(1997).In search of optimal long-term female hormone replacement: the potential of selective receptor modulators.Horm. Res.,48,155-163.
21. Mori-Abe, A.,Tsutsumi, S.,Takahashi, K.,Toya, M.,Yoshida, M.,Du, B.,Kawagoe, J.,Nakahara, K.,Takahashi, T.,Ohmichi, M.,Kurachi, H.(2003).Estrogen and Raloxifene induce apoptosis by activating p38 mitogen-activated protein kinase cascade in synthetic vascular smooth muscle cells..J. Endocrinol.,178,417-426.
22. Paganini-Hill, A.,Dworsky, R.,Krauss, R.M.(1996).Hormone replacement therapy, hormone levels, and lipoprotein cholesterol concentrations in elderly women.Am. J. Obstet. Gynecol,174,897-902.
23. Ross, R.(1993).The pathogenesis of atherosclerosis: a perspective for the 1990s..Nature,362,801-809.
24. Rossouw, J.E.,Anderson, G.L.,Prentice, R.L.,LaCroix, A.Z.,Kooperberg, C.,Stefanick, M.L.,Jackson, R.D.,Beresford, S.A.,Howard, B.V.,Johnson, K.C.,Kotchen, J.M.,Ockene, J.(2002).Writing Group for the Women's Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial.JAMA,288,321-333.
25. Setacci, C.,la, Marca, A.,Agricola, E.,Morgante, G.,Setacci, F.,Cappelli, A.,Petraglia, F.,De Leo, V.(2002).Effects of the selective estrogen receptor modulator, raloxifene, on carotid artery pulsatility index in postmenopausal women.Am. J. Obstet. Gynecol.,186,832-835.
26. Soma, M.R.,Oswago-Gadda, I.,Paoletti, R.,Fumagalli, R.,Morriset, J.D.,Moschia, M.,Crosignani, P.(1993).The lowering of lipoprotein (a) induced by estrogen plus progesterone replacement therapy in postmenopausal women.Arch. Intern. Med.,153,1462-1468.
27. Somjen, D.,Kohen, F.,Jaffe, A.,Amir-Zaltsman, Y.,Knoll, E.,Stern, N.(1998).Effects of gonadal steroids and their antagonists on DNA synthesis in human vascular cells.Hypertension,32,39-45.
28. Takahashi, K.,Ohmichi, M.,Yoshida, M.,Hisamoto, K.,Mabuchi, S.,Arimoto-Ishida, E.,Mori, A.,Tsutsumi, S.,Tasaka, K.,Murata, Y.,Kurachi, H.(2003).Both estrogen and Raloxifene cause G1 arrest of vascular smooth muscle cells.J. Endocrinol.,178,319-329.
29. Tan, Zh.,Yang, D.,Lu, W.,Pan, J.Y.,Wang, T.H.(2001).Effect of inhibition by 17-βE(subscript 2) on endothelin-induced proliferation of vascular smooth muscle cells.Chin. J. Appl. Physiol.,17,251-254.
30. Walsh, B.W.,Kuller, L.H.,Wild, R.A.,Paul, S.,Farmer, M.,Lawrence, J.B.,Shah, A.S.,Anderson, P.W.(1998).Effects of raloxifene on serum lipids and coagulation factors in healthy postmenopausal women.JAMA,279,1445-1451.
31. Wang, T.H.,Tan, Zh.,Fu, X.D.,Yang, D.,Hu, F.X.,Li, Y.Y.(2003).Effect of ERK on 17-β-estradiol-induced inhibition of VSMC proliferation in rats after vascular injury.Acta. Physiol. Sin,55,411-416.

1. Tsai, Fuu-Jen,Tsai, Chang-Hai,Liou, Yi-Fan,Lin, Jing-Ying,Lin, Chien-Chung,Kuo, Chia-Hua,Ju, Da-Tong,Huang, Chih-Yang,Hsieh, You-Liang,Ho, Tsung-Jung(2015).Attenuation of Magnesium Sulfate on CoCl2-Induced Cell Death by Activating ERK1/2/MAPK and Inhibiting HIF-1α via Mitochondrial Apoptotic Signaling Suppression in a Neuronal Cell Line.中國生理學雜誌,58(4),244-253.