Effects Of The Combined Bu-shen-ning-xin Recipe And DHEA On Atherosclerosis Of The Ovariectomized Rabbits

Background: When women enter their peri-monopause period, great changes take place in their cardiovascular system, especially the incidence of atherosclerosis gradually approaches to that of male, which is probably due to the sharp decrease of estrogen. Although some clinical and basic researches suggested that estrogen had protective effects on cardiovascular system of menopausal women, cardiovascular diseases are no longer listed as indication of Hormone replacement therapy (HRT) according to mid-period results of the Women's Health Initiative randomized controlled trial in 2002. Traditional Chinese Medicine will probably become an interesting and effective means to cure the diseases of peri-monopause period. Recently some research showed that dehydroepiandrosterone, DHEA, appeared to its anti-senescence effects. Suitable supplement of DHEA will postpone senescence and improve diseases related to senescence, for example improving the function of cardiovascular and immune systems.Objectives: To explore the protecting effects of DHEA and the Bu-shen-ning-xin recipe on atherosclerosis of ovariectomized rabbits and the injured endothelial cells, using estrogen as positive control, so as to provide evidences for western medicine combining with Traditional Chinese medicine to prevent and treat atherosclerosis of peri- and post-menopause.Methods: A series of methods, such as primary cell culture, flow cytometry, scan and transmission electron microscope, enzyme-linked immuno-sorbent assay, immunohistochemistry and semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) were employed to investigate the effects of estrogen, DHEA and the Bu-shen-ning-xin recipe on atherosclerosis of ovariectomized rabbits, the injury of endothelial cells, other functions and the interaction of endothelial cells to monocytes. Results: Comparing with the ovariectomized group, estrogen could decrease the level of triglyceride of ovariectomized rabbits, but it had no effect on the level of serum total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol. DHEA and the Bu-shen-ning-xin recipe had no effect on serum lipid status of ovariectomized rabbits. The ovariectomized rabbits were treated respectively with estrogen, DHEA or/and the Bu-shen-ning-xin recipe, the area ratios of atherosclerosis lesion to endothelium, the thickness and area ratios of endothelium to the medium were lower than those of the ovariectomized group. Estrogen, DHEA and the Bu-shen-ning-xin recipe all alleviated the pathologic damage of aortas, depressed significantly the VCAM-1 expression of endothelial cells in atherosclerosis plaque. Comparing with the ovariectomized group, estrogen, DHEA or the Bu-shen-ning-xin recipe all could increase the level of serum NO of ovariectomized rabbits. The level of serum estradiol of the ovariectomized animals descended significantly, and estradiol benzoate could increase the level, the Bu-shen-ning-xin recipe had no effect while DHEA could slightly increase the level. Estradiol benzoate down-regulated the expression of estrogen receptor of endothelial cells while the Bu-shen-ning-xin recipe and DHEA up-regulated the expression. Endometrial hyperplasia of the ovariectomized rabbits is obvious after being treated with estradiol benzoate, while there was no such phenomenon in the ovariectomized rabbits treated with the Bu-shen-ning-xin recipe or DHEA. Comparing with the ovariectomized group, estradiol benzoate, the Bu-shen-ning-xin recipe and DHEA all relieved fat infiltration of livers. The Bu-shen-ning-xin recipe, especially DHEA promoted immune function from Th2 to Th1 bias, while estrogen had no such effects. The oxidized low density lipoprotein (ox-LDL) can significantly decrease the synthesis of nitric oxide (NO), increase the production of malondialdehyde (MDA) and induce the injury and apoptosis of endothelial cells. The content of MCP-1 in the conditioned medium of HUVECs (EC-CM) increased, and ox-LDL significantly up-regulated the expression of ICAM-1, V...