Hl immigrated to America.

Isoflavone (soybean isoflavone) is a phytoestrogen, and daidzein (daidzein) and daidzein are the most abundant in soybean. Their structures are similar to estrogen, and they are aromatic rings: they contain non-steroidal compounds. Soybean isoflavone in soybean is an active form that usually does not combine with glycoside, and it can only be decomposed by glycosidase of intestinal flora to form bioactive non-glycoside isoflavone. Naturally, chickpea (chickpea) and formononetin (formononetin) enter the role of soybean isoflavone, daidzein and genistein in intestinal flora. Regardless of the precursor, genistein can further metabolize p-methylphenol and daidzein, and can be decomposed into more active equol (equol) and O- dimethyl estrin (O-DMA). Is it the intestinal flora that decomposes isoflavones, which are easily absorbed by the human body and secreted directly from bile to the outside of the intestine? Enterohepatic circulation, a deglycoside isoflavone, is metabolized and combined with glycoside to form bioactive compounds. Differences in soybean varieties, producing areas, harvest seasons, fungal infections and the intake of the Gang of Four. The average isoflavone intake of Japanese residents is 20? 30 mg/day, and residents of developed countries such as Europe and America

Low isoflavone intake. Because the main factors affecting the intestinal flora of large intestine, such as sex, dietary fat and fiber, isoflavone level of endogenous estrogen metabolism, etc., will have the same degree of influence on soybean isoflavone metabolism. Therefore, even if the same isoflavone is ingested, the plasma isoflavone concentration of different individuals is very different, which may be one of the reasons why different plant researchers have different or even opposite research results.

Soybean isoflavones are linked to two or three hydroxyl groups and aromatic rings. This structure is relatively stable, and it can easily cross the cell membrane, which is beneficial for binding and accepting protein and enzyme. Isoflavones that bind to estrogen receptor (ER) and have estrogenic activity and antiestrogenic activity have similar structural characteristics. The protective effect of isoflavones on health and the preventive and therapeutic effect on diseases are mostly determined by two important biological activities. The activity of isoflavones in cells and in vivo mainly depends on the endogenous estrogen level of local concentration and the ER level of tissues and organs. Isoflavones have weak estrogenic activity. Usually, only estrogens1000-300,000 isoflavones compete with estrogens for higher concentrations of estrogen receptors for anti-estrogenic activity, thus showing. The biological activities of soybean isoflavones include antioxidant activity, inhibiting cell proliferation and differentiation, anti-tumor angiogenesis, and promoting the synthesis of sex hormone binding globulin (SHBG).

The occurrence of diseases caused by soybean diet is related to soybean isoflavone and human health. Epidemiological investigation shows that the incidence of breast cancer, cardiovascular disease and climacteric hot flashes in Asia (especially Japan) is significantly lower than that in Europe and America, but this difference is considered to be closely related. High-fiber diet and high-fat diet are closely related to the diets in Europe, America and Asia, but with the deepening of research, phytoestrogens (soybean isoflavones) are these. Most scholars believe that the main reason for the difference in soybean isoflavone intake is the pathogenesis of this disease. So far, a large number of epidemiological investigations, clinical trials, animal experiments and in vitro experiments have confirmed that soybean isoflavones are women's efforts. It plays an important role in the pathogenesis, prevention and treatment of postmenopausal vascular diseases, breast cancer and postmenopausal hot flashes of osteoporosis.

After women enter menopause, ovarian function declines, and the synthesis and secretion of estrogen decrease, which will lead to the metabolism of fat and cholesterol. Husbands often have obese cardiovascular and cerebrovascular diseases, and the cholesterol of postmenopausal women increases, and the incidence and mortality of cardiovascular diseases increase. According to statistics, the incidence of coronary heart disease in postmenopausal women has increased by 2? The use of estrogen replacement therapy (ERT) by premenopausal and postmenopausal women is more than 3 times, and the risk of cardiovascular disease is reduced: 35% to 50% of the studies show that only soybean isoflavones with estrogen activity can play an important role. The epidemiological survey in Sichuan shows that the incidence of cardiovascular diseases among women aged 40 to 69 in the United States is the same as that in Japan. Soybean protein rate, reducing atherosclerosis is mainly due to the difference in mortality. Compared with developed industrial countries, the mortality rate of coronary heart disease in Singapore is similar. However, due to the huge differences in lifestyle and food culture in Asia, Europe, the United States and other countries, the role of other factors or food ingredients in coronary heart disease cannot be ruled out. Okazaki also has different views on the epidemic and needs further study.

Clinical trials, animal experiments and in vitro studies further confirmed the role of soybean isoflavones in vascular diseases. In the dietary intervention experiment, it was found that women and normal blood cholesterol intake of 45 mg isoflavones per day can increase blood cholesterol. In a 6-month intervention trial for postmenopausal women with hypercholesterolemia, the experimental group ingested 40 grams of soy protein every day, and found that the total cholesterol in plasma decreased by about 0.40mmol/L, and the proportion of total cholesterol decreased, while the high-density lipoprotein (HDL) increased by 0.065mmol/L year-on-year. After the experiment, the HDL cholesterol was 0.5. The results showed that soybean isoflavones reduced the cholesterol in plasma. A meta-analysis of the relationship between 38-year-old Anderson and soybean isoflavone, blood lipid or cholesterol showed that the average intake of soybean isoflavone in these experiments was 479/ day, while the average level of serum total cholesterol decreased by 0.59 mmol/L(9.3%). 1 1 AYlthOYly The research group used macaques to study the blood lipid parameters of cardiovascular diseases caused by soybean protein on a high-fat diet. Female macaques were divided into three groups: diet and casein from protein, diet (ethanol extract), soybean protein with isoflavones removed as protein source, and soybean crude protein extracted from Illinois feed as H quality source of eggs (at 1 stage, 143mg isoflavones per day). Some experimental results are shown in Table L. It can be seen that soybean protein containing isoflavones can effectively reduce total cholesterol and low density lipoprotein (LDL). Very low density lipoprotein (VLDL) level, and inhibit the formation of atherosclerotic plaque. In this study, there is only a little evidence of the protective effect of soybean isoflavone on cardiovascular diseases, but it also shows that soybean protein H and isoflavone have lipid-lowering effect. The mechanism of soybean isoflavone in cardiovascular diseases has been widely studied. In the past 20 years, researcher Anthony Ly summarized the diversity of its mechanism as follows:

(1 )LDL receptor regulation. Soybean isoflavone LDL receptor can improve the occurrence of LDL receptor and increase its activity, which is beneficial to cholesterol clearance. (2) Oxidation resistance. In vitro studies have shown that soybean protein can reduce the volume of low-density lipoprotein particles and protect low-density lipoprotein from over-oxidation, while isoflavones with this effect can reduce the deposition of low-density lipoprotein particles, thus reducing the incidence of coronary atherosclerosis, and (3) inhibiting the proliferation of vascular smooth muscle cells. Cell culture of 25 mm/l genistein can reduce the basic fibroblast growth factor (bFGF) and fibrinogen? The activity of plasminogen activator A inhibits the proliferation of smooth muscle cells and plays an important role in the development of atherosclerosis. This kind of cell is proliferating and has the function of anti-thrombosis. Protein tyrosine phosphorylation is closely related to platelet activity. Genistein can reduce the platelet H of tyrosine eggs by inhibiting tyrosine kinase phosphorylation, thus reducing platelet activity, reducing its deposition and accumulation on the blood vessel wall, thus reducing and preventing the occurrence of atherosclerosis. Nakajima studies that flavonoids and daidzein can stop bleeding. Bolt's Prime Minister Az binds to his receptor, which leads to the non-response of platelet isoflavones. Therefore, this mechanism needs further study. Recently, some scholars began to pay attention to the role of lipoprotein H (I) ILP (I) "in the protective mechanism of isoflavones. LPB) is an independent risk factor of coronary heart disease, which is related to the influence of diet, drugs and postmenopausal women.

Estrogen therapy significantly reduced the concentration of the substance, Okazaki changes, the binding characteristics of soybean 000 indigenous and estrogen active dye genistein and estrogen receptor. Some scholars speculate that isoflavones can reduce LP(a) to reduce the risk of coronary heart disease, which needs research to confirm. Abnormal transformation growth steel PL(TGF 6 1) reduces the risk factors of coronary heart disease, and genistein can induce the formation of TGF PL, which is also considered to be the mechanism of isoflavone.

breast cancer

Investigation on soybean intake and incidence of breast cancer among epidemic college students. Ingram and other long-term epidemiological surveys found that soybean milk intake was negatively correlated with the incidence of breast cancer. When China and I immigrated to the United States that day, the incidence of breast cancer was still lower than that of 10 residents in the control study. This may be that the soybean intake in the early and middle stages is about: Taking Si Wu as an example, through the comparative analysis of countries in 1.990, it was found that in developed countries such as Europe and America, and in countries such as Asia, with the increase of daily soybean intake or soybean consumption of residents, rats were fed with feed containing soybean protein, and then exposed to chemical carcinogens. The results show that soybean protein can prevent tumor formation and provide strong epidemiological evidence for the incidence of breast cancer in Sichuan. However, after repositioning, isoflavone soy protein can combine with ethanol to inhibit tumor disappearance. This study confirmed that genistein and daidzein could inhibit the production of DNA adducts induced by 7, 12 monotoluene onion. The research results of Lamartiniere's soybean isoflavone in breast cancer are more convincing. To study the prognosis of neonatal rats fed with 7,u dimethyl genistein every time, it was found that genistein could prolong the incubation period of cancer and significantly reduce the incidence of breast cancer in adult rats. It shows that early exposure to isoflavones is beneficial to prevent cancer in the second half of the year, which can also be used to explain why the incidence of breast cancer among Asian immigrants in the United States (early stage of high soybean isoflavone intake) is still lower than that in the United States. BR/>；

The results of cell culture experiments further confirmed the inhibitory effect of soybean isoflavone on breast cancer, and also revealed the anti-cancer mechanism of soybean isoflavone. At present, soybean isoflavone (genistein) involves estrogen receptor-dependent and estrogen receptor-independent mechanisms in in vitro experiments of mouse and human breast cancer (MCF-7). . Cytological related compounds with heterogenous reactions are estrogen receptor positive, estrogen or estrogen-like. In MCF-7 cell culture, it was found that low concentration of genistein could promote cell proliferation, but when the concentration of genistein and genistein yellow ketone was greater than 0, I0mmol inhibited cell proliferation. Estrogen exists, and the former can competitively bind to the core of estrogen receptor, thus avoiding the formation of adducts between estrogen and mutagenic DNA. These studies show that the inhibitory effect of soybean isoflavone on breast cancer is mediated by er channel. However, another study shows that. SX 10-5IX-4mol Some genistein can inhibit human breast cancer MCF -7 cells. Researchers believe that the advantage of this concentration range is that tyrosine kinase and DNA topoisomerase are closely related to epidermal growth factor, insulin-like growth factor and cell growth factor receptor of platelet-derived growth prisoners, and they play an important role in preventing cell proliferation and transformation by inhibiting the proliferation of tyrosine kinase cancer cells. Genistein inhibited 1 1 type DNA topoisomerase cancer cells and protein from combining with DNA strand breaks, and the cancer cells died. Genistein inhibits non-ER by interfering with receptor signaling pathway and DNA dependence. Genistein can interfere with EZ's activity of reducing ERmRNA expression and decrease endogenous estrogen in vivo, which is one of its anti-estrogen mechanisms.

Genistein has antioxidant effect and inhibits the production of peroxide. Genistein can strongly inhibit the production of H202 12-0 phenol induced by tumor-promoting phorbol 13- vinyl acetate (TP) in human polymorphonuclear lymphocytes (neutrophils) and HL-60 cells, and the equal concentration range is 1? 1.5 mmol has a certain dose-effect relationship. Genistein can inhibit the production of superoxide anion in HL-60 cells. Because it is harmful to steel, hydrogen peroxide induces cancer, which is one of the anticancer mechanisms of flavonoids with antioxidant effect.

Studies have shown that genistein can affect the activity of hormone metabolizing enzymes. Aromatase is an estrone invertase which converts androgen into estrone decarboxylase. These metabolic activities can inhibit the transformation of estradiol and reduce the concentrations of genistein, cell, estrone and estradiol, thus preventing estrogen from forming DNA adducts in cells, thus achieving the purpose of inhibiting cancer. Soybean isoflavone can inhibit the secretion of estrogen by this enzyme, and it can also change the types and contents of estrogen metabolites in the body, which has been confirmed by human experiments. 12 premenopausal women take soybean protein equivalent to 10, 15, 129 mg/day of soybean isoflavones, and the metabolites of 4 EI and (OH)4(OH) EZ I6(OH estrogen lasting 100 are obviously reduced. According to this result, Xu et al. proposed that estrogen metabolism is one of the anticancer mechanisms of soybean isoflavones. Some scholars believe that isoflavone can promote the synthesis of sex hormone-binding globulin and prolong menstrual cycle, but its possible anticancer mechanism.

Postmenopausal hot flashes and osteoporosis

Female menopause, estrogen levels will cause a series of hot flashes and sweating, which is a symptom of menopause. The continuous loss of bone is a natural aging process, and the incidence of osteoporosis in elderly women is more than that in men. The main reason is that the estrogen level of menopausal women decreases rapidly, which accelerates the combination of estrogen receptor, estrogen and estrogen receptor with bone shame, reduces the activity of osteoclasts, and thus limits bone resorption, which is beneficial to the prevention and treatment of postmenopausal osteoporosis. Epidemiological survey shows that in Japan, 25% of menopausal women complain about hot flashes and sweating, but in North America, the proportion of such women is as high as 85%. Osteoporosis in Postmenopausal Women In Japan and Europe and America, the incidence of osteoporosis is significantly lower than that in Europe and America. In recent 10 years, scholars from all over the world have conducted a large number of clinical trials and animal experiments, trying to find out the relationship between soybean intake and osteoporosis and hot flashes in postmenopausal women. 12 weeks. Albertazzi 104 cases of postmenopausal women and 609 cases of soybean protein diet intervention test, it was finally found that some% of patients' hot flashes disappeared and increased significantly: the experimental results showed that soybean protein significantly improved the hot flashes symptoms of postmenopausal women. Other people's experiments also observed the effects of vaginal cytology and hot flashes on soybean protein, but the results were not consistent in the experimental area, research population, bean products form and detection time. Clinical trial on the relationship between hypercholesterolemia and soybean isoflavone osteoporosis in postmenopausal women. Recently, in Porter's diet intervention experiment, 66 women were divided into three groups, the control group. One group took 56 mg of isoflavones every day, and the other group took 90 mg of isoflavones every day. The results showed that the bone mineral content and bone density of the subjects who ingested 90 mg isoflavones every day increased by 2%, which was significantly different from that of the control group.

It is a strong evidence that clinical use of ipriflavone can reduce the relationship between isoflavones and osteoporosis after menopause. Soybean isoflavones synthesized by isopropyl flavone can be used as drugs to treat acute ovarian dysfunction isoflavones and osteoporosis, and taken for 200? 600 mm can effectively increase bone mass and reduce bone loss, which may be transformed into various metabolites with intestinal bacteria, including daidzein. In fact, at present, it mainly focuses on ovariectomized rats as model animals. A large number of studies have shown that soybean isoflavones reduce bone loss and promote bone formation. The above chronic diseases are hormone-dependent diseases. In addition, studies have shown that soybean isoflavones can prevent hormone-dependent diseases or injuries. The antioxidant properties of soybean isoflavone can protect DNA from ultraviolet rays, prevent liver injury caused by ischemia-reperfusion diabetes 1 1, and improve renal function and proteinuria. In short, a large number of epidemiological and clinical experiments, animal studies and in vitro experiments have confirmed that soybean isoflavone has a protective effect on female chronic diseases. Needless to say, increasing the intake of soybeans and bean products is accompanied by the health of an aging society. It is beneficial to human health. Postmenopausal women have attracted the attention of the whole society. One hope of ERT in the treatment of low estrogen-related diseases is to accept ERT, which will increase soybean isoflavones in women with breast cancer, menopause and postmenopausal estrogen-dependent diseases, and has a good application prospect.

However, the relationship between soybean isoflavones and diseases still needs further study. So far, soybean protein holds the opposite view on the role of cholesterol in blood: the relationship between isoflavones and cancer can only be inferred from human cell lines and animal experiments, and the human body needs more human intervention. The relationship between soybean isoflavone hot flashes and osteoporosis needs more human experiments to further confirm its mechanism. The interaction between soybean isoflavone and other food ingredients has not been reported, and the recommended daily dosage of each soybean isoflavone has not been finalized. Therefore, there is still a lot of work to be done to study the function and mechanism of soybean isoflavones in detail.