Title Clinical Trial of the Phytoestrogen-rich Herb; Pueraria mirifica as a Crude Drug in the Treatment of Symptoms in Menopausal Women
Author Verasing Muangman, M.D.* Wichai Cherdshewasart, D.Sc.**
Subject Clinical Trial of the Phytoestrogen-rich Herb; Pueraria mirifica as a Crude Drug in the Treatment of Symptoms in Menopausal Women
Institute of Research
Date Issue
Keyword
Abstract

Abstract : The clinical trial to evaluate the estrogenic effects of the crude drug derived form dry powder of a phytoestrogen-rich Thai herb Pueraria mirifica (White Kwao Krua) in five female volunteers with menopausal symptoms showed that the crude drug clarly improved the signs and symptoms resated to menopause such as, hot flushes, frustration, sleep disorder, skin dryness, high blood cholesterol, oligomenorrhoea and amenorrhoea; with no change in the blld cells, liver and kidney functions, as well as other physiological status after four months of treatment. In four volunteers, treatment were continued to complete a one-year test period with half the dose and was found to maintain their satisfied menopausal relief status. The crude drug dosage was administered at 200 mg daily for three weeks a month during the first four months to treatment and 200 mg every other day for 20 days per month for the remaining eight months. These doses were effective and safe as phytoestrogen treatment of menopausal symptoms.

Introduction
Menopause sometimes causes symptoms derived from decreased blood estrogen levels among middle-aged females. Estrogen Replacement Therapy (ERT) has been employed to protect and relieve symptoms but usually results tin substantial cost and long-term treatment has a certain risk of estrogen-related cancer1. Some recommendations such as lifestyle changes were proposed to minimize the menopausal symptoms2,3. Dietary and other natural therapies, especially soy products which contain significant levels of phytoestrogens, namely isoflavones, were shown to be not only effective in eliminating certain menopausal symptoms4-7, but also act as a potent anticancer therapy8-10.  P. mirifica (Airy Shaw et Suvatabandhu) or White Kwao Krua is a Thai indigenous herb with a Long history of domestic consumption as a rejuve- Nating herb to promote youthfulness in both women and men11. The herb was first brought to public at-Tention in 1932 by a report that the tuberous root of
The kwao krua herb found in the Northern Thailand contained active constituent with such rejuvenating property12. That report elicited a study of the benefits of the herb and it was later proven in both animal experiment and clinical trial in a hospital by administering alcoholic crude extract of the herb13.

Such human benefit was also confirmed by another study14. The herb was initially recognized as Butea superba, and was finally identified and clearly established as Pueraria mirifica15.
Active ingredient were isolated and studied
From the herbal tuber and was found to contain miroestrol6,17 which exhibited the key estrogenic effect as reported from the studies in immature female mice18 and ovariectomized rats19. A very interesting result was obtained form a clinical trial in nine female volunteers at the Chelsea Hospital

Women in London, U.k., who were suffering from amenorrhea, as well as one volunteer with artificial menopause. The results clearly demonstrated that this active ingredient from P.mirifica could be administered as an estrogen supplement20. Other chemical constituents were also characterized including daidzin, daidzein, genistein, coumestrol, mirificain21, genistin22, puerarin23 and kwakhurin24. The phytochemical daidzin from soy source was shown to prevent bone loss25. Daidzein was reported to have immune enhancing activity26, inhibitory action on induced lung metastasis27 and on specific mutagenicity28. Genistein was shown to have a negative result in Ames test for mutagenesis and act as a specific inhibitor of tyrosine kinase30, an inhibitor of human breast cancer cell proliferation31-33, as well as reducing bone loss34. Coumestrol was shown to be an estrogen supplement35 and an anti-osteoporosis agent36. Stigmasterol was reported to have cholesterol lowering action.37 β-Sitosterol was shown to reduce benign prostate hyperplasia38,39 and inhibit human colon cancer growth40, as were mirificaoumestan and its derivatives41,42. Recently, deoxymiroestrol, with stronger estrogenic effects than that of miroestrol was also isolated43.

Thailand is the main natural habitat of P.mirifica with a long history of consumption record. While soy is currently used for prevention and treatment of menopausal symptoms, this preliminary clinical trial with P.mirifica in Thai women could help evaluate its potential use for long-term phytoestrogen supplementation and provide basic information to intitiate a full-scale clinical trial. Such a trial could help us to clearly understand how the crude drug works in menopausal women.

MATERIALS AND METHODS

1. Crude Drug Preparation
The fresh tuber of P. mirifica cultivar
“Wichai-III” was collected, cleaned, peeled, sliced into pieces, dried in a hot air oven until nearly completely dried, ground into fine powder of 100 mesh size particles and finally filled into capsules with the net filling filled into capsules with the net filling amount of 200 mg per capsule. Isoflavone contents were analyzed by high performance liquid Osaka, Japan, from the powder with the aid of puerarin, daidzin, daidzein, genistin and genistein as references and subsequently used as active ingredient markers.

2. The Volunteers
Menopausl women with a history of cyst formation at the breast, uterus and / or ovary were excluded. Five accepted volunteers were the outpatients of Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand, with an age range from 35 to 52 years. These women suffered from oligomenorrhoea or amenorrhoea, hot flushes, frustration, skin dryness, weakness and/or sleep disorder. The volunteers had complete blood cell count and blood chemistry analysis including haemoglobin, haematocrit, blood urea nitrogen, creatinine, SGOT, SGPT, cholesterol, triglycerides and urinalysis. The selected volunteers had to be in a normal health with normal blood chemical analysis results. They were verbally informed about the detail of the crude drug and the consumption of one 200 mg capsule a day for the first 21 days of the month for a 4 months period. If drug administration had to be extended, 1 capsule would be consumed every other day for the first 20 days of the month until the end of the 12th month. The volunteers were recruited for the first 4 months trial period, whereas 4 volunteers were asked to complete the one-year test period.

3. Evaluation Criteria
31. Physical Examination Record
The body weight, height, breast, waist and hip sizes of the volunteers were recorded just prior to the test, as well as monthly when they came on appointment to receive a new capsule batch, and again at the end of the test.
3.2 Medical Interview
A medical doctor interviewed the volunteers with standard questions just prior to the test, as well as monthly, and firnally at the end or the test.
33. Total Blood Count and Blood Chemis-try Analysis
Blood was collected for total blood count and blood chemistry analysis. The results were ana-lyzed just priod, and at the end of the 12th month test period.

RESULTS
The results from the four-month and one-year study from five selected volunteers are indivi-dually described as follows:-
Volunteer No. 1, 46 years old, weight 48 kg, height 1.47 m, had experienced amenorrhoea pe-riod for 4 months with clear menopausal symptoms exhibited as hot flushes, frustration, sleep disorder and skin dryness. Physical examination as well as total blood count and blood chemistry analysis, were normal.

After completion of the 1st month test pe-riod, it was found that the patient’s appetite increased, the body weight increased by 0.5 kg and recovered from hot flushes, frustration and skin dryness (especially facial skin).
After completion of the 2nd month test pe-riod, the patient had recovered from sleep disorder. After completion of the 3rd month test period, all recovering symptoms were maintained.

After completion of the 4th month test pe-riod, the patient had recovered from sleep disorder. After completion of the 3rd month test period, all recovering symptoms were maintained.

After completion of the 4th month test pe-riod, the recorde menopausal symptoms showed remarkable recovering from the hot flushes, frustra-tion, sleep disorder, and skin dryness. Total blood count and blood chemistry analysis revealed that the body responded to the crude drug normally, while the patient’s recorde weight increased by 0.5 kg and no recurrence of menstruation period was observed. The volunteer was satisfied with the test results and stopped consumption of the crude drug at that time.

Volunteer No. 2, 52 years old, weight 47
kg, height 1.47 m, had experienced amenorrhoea period for 5 years with obvious menopausal symptoms as exemplified as hot flushes, frustration, sleep disorder and wrinkled facial and body skin. Her physical examination was normal .The total blood count and blood chemistry analysis were normal except blood cholesterol which was recorded as 247 mg%.
After completion of the 1st month test period, the facial skin had become firm while the body weight increased by 1 kg.
After completion of the 2nd month test period, full recovery from the sleep disorder symptom had occurred and her frustration had been abolished. The body weight increased by 3 kg. Her breasts were firm and showed a 2.5 cm increase in size. Two and a half cm increase in size of the waist and the hip had occurred.

After completion of the 3rd month test period, the skin was firm and hot flushes no longer occurred. Her total blood count was normal. The blood chemistry analysis showed a sharp decrease in blood cholesterol level from 247 to 205 mg% (17.0% decrease). After completion of the 4th month test period, the patient showed full recovery from all recorded menopausal symptoms. The facial and body skin were firm and shiny. The net weight gain was 3 kg and recurrence of the menstruation was not observed.The volunteer kept taking the crude drug until the end of 12th month. It was found that the previously recorded recovery from menopausal symptoms as well as the facial and body skin firmness were all maintained while the menstruation did not recur. The volunteer was satisfied with the test results.

Volunteer No. 3, aged 35 years old, weighed 62 kg, 1.66 m height. This patent had had amenorrhoea for 7 months, was submitted to heart surgery (PDA ligation) 18 years ago, and also regularly suffered from constipation, sleep disorder, frustration, itching and a moderate amount of facial acne. Her total blood count and blood chemistry analysis were normal.
After completion of the 1st month test pe-riod, the breast size had increased by 2.5 cm and Were firm; her body skin became healthy and shiny; her facial acne disappeared resulting in clear face appearance. After completion of the 2nd month test pe-riod, the recovered symptoms were maintained as recorded in the 1st month. After completion of the 3rd month test pe-riod, the amenorrhoea symptoms were fully disap-peared as the volunteer exhibited menstruation pe-riod, itching was fully recovered, as well as sleep disorder andconstipation. The body weight incre-ased by 0.4 kg. After completion of the 4th month test per-iod, the menstruation period was recorded for2 days, the body weight had increased by 1.5 kg, the breast size remained the same as that recorded before the test, but became firmer. The hip and waist circum-ferences had increased by 2.5 cm. Total blood count and blood chemistry analysis were normal. The volunteer kept taking the crude drug until the end of 12th month. It was found that sleep disorder and frustrate symptoms were completely absent and the volunteer felt that she was in a good mood. Facial and body skin had recovered from dryness and retained firmness. The menstruation period was finally found to be irregular with increased volume. The final body weight increased by 2 kg. The volunteer was satisfied with the test results.
Volunteer No. 4, aged 49 years old, had had right ovariectomy. Her weight was 68 kg, and the height was 1.56 m. She had an irregular menstrual-tion period, and thus, was classified as oligomenor-rhoea. She had hot flushes and rheumatism, but her total blood count and blood chemistry analysis were normal.

After completion of the 1st month test pe-riod, the volunteer felt breast pain starting from the 3rd day. The result of breast examination revealed no abnormality in term of cyst formation.
After completion of the 2nd month test pe-riod, the menstruation period was found to be nor-mal.The breast pain persisted but at a lower degree.
After completion of the 3rd month test pe-riod, the breast size had increased by 2.5 cm. She still had breast pain.
After completion of the 4th month test pe-riod, the skin became healthy and firm; backache remained; shorter menstruation period was found.
Urinary problems such as mild dysuria occurred for
some times. Laboratory results were normal.
The volunteer kept taking the crude drug until the end of one-year study period. Physical examination results were normal. The body weight was stable and the skin was healthy and firm. The regular menstruation period was maintained. The dysuria was investigated and white blood cells (6-10 cells/HPF) were found in urine. She was treated with ofloxacin for 7 days and the symptom was eliminated. The volunteer was satisfied with the test results.
Volunteer No.5, 39 years old, had a weight of 49.3 kg, a height of 1.58 m, and had been married for 12 years without having a baby. She had exhibited a fibroadenoma breast condition for 6 years. She was classified as oligomenorrhea due to the fact that the menstruation period had been reduced from 7 days to 3 days. She regularly had headaches and frustration. The total blood count and blood chemistry analyses were normal except blood cholesterol level which was normal except blood cholesterol level which was 237 mg%.
After completion of the 1st month test pe-riod, a fine acne had occurred on the face since the end of the 2nd week and thereafter developed into abundant acne for 1 week before completely disap-peared. The menstruation period became normal with fresh color.
After completion of the 2nd month test pe-riod, the frustration had abated; the headaches had disappeared; the skin became healthy and firm; clear secretion was observed within the vagina; the breasts had increased by 2.5 cm in size and were firm while the waist and hip circumferences and the body weight remained the same.
After completion of the 3nd month test pe-riod, the menstruation period remained normal, as well as other parameters.
After completion of the 4th month test pe-riod, the menstruation period remained normal; the skin was healthy and firm; the body weight had in-creased by 1 kg. Total blood count and blood che-mistry analysis were normal except blood choles-terol level which had decreased from 237 to 205 mg%(13.5% decrease).
The volunteer was asked to keep taking the crude drug until the end of the one-year study pe-riod. The normal menstruation period and the healthiness and firmness of the skin were fully maintained. The body weight had increased by 1 kg while the breasts were firm and had increased by 1 cm in size. The waist had also increased in size. The volunteer was satisfied with the test results.
The reported cases versus recovering cases in five menopausal women after 4 months consum-ption of P. mirifica crude drug are summarized in Tablel. The number of cases that exhibited adverse side effects is summarized in Table 2.

DISCUSSION
The crude drug prepared from the powder of P. mirifica cultivar Wichai-III was tested in five menopausal volunteers with oligomenorrhoea or amenorrhoea symptoms. The test was designed for 4 and 12 months test periods.
The results (Table 1) revealed that two volunteers with oligomenorrhoea symptom showed an estrogenic response to the crude drug that reflected in clear improvement of the menstruation period. The findings implied that phytoestrogens from P. mirifica cultivar Wichai-III exhibited trophic effects to the uterus similar to those from estrogen or phytoestrogens from other sources. The trophic effects were most likely fully functional if the uterus was still in a fresh status, as in the case of oligomenorhoea, but they might not fully work in the two cases with amenorrhoea at the age of 46, lasting for 4 months and another at the age of 52, lasting for 5 years. The uterus in such cases might be developing into an atrophic status while the younger woman at the age of 35 years, lasting for 7 months could recover for the menstruation peiod at the end of the 3rd month. This result was most likely to occur by the same reason as that of the oligomenorrhoea. Furthermore, in one case, the clear secretion released from the vagina was noted as a sign of adverse effect (Table 2). It was most likely to result from cervical and/or vaginal secretion due to the estrogenic effect that was normally found per se in normal menstrual cycle. This finding helps confirm that estrogen receptor (ER) β is present in the human cervix44 or vaginal lining and can respond to P. mirifica phytoestrogens as well.

Table 1.Number of cases suffering with reported symptoms and that recovered after four months consumption of P. mirifica crude drug.

Table 2. Number of case exlibited the adverse effects after four months consumption of P. mirifica crude drug.
 

Adverse effects	Number of cases
Body weight increase	4
Hip and waist sizes increase	2
Breast pain	1
Breast size increase	3
Transient breast size increase	1
Transient development of acne	1
Vaginal secretion	1
Increased appetite	1

The breasts increased in size in three cases, and transient enlargement occurred in one case. The enhancement of breast firmness, a sign of breast restitution, resulted in an increase in breast elasticity in of breast tissues to P. Mirifica phytoestrogens by an increase in the elasticity of the breast skin as well as by grater accumulation of water and/or fat within the breast tissue. Breast pain which occurred rapidly in one case should result from increasing pressure in situ derived from water retention within the breast tissue, as always occurs by estrogen just prior to the menstrual period. In this case such pain was prolonged and finally partially habituated. It was mainly due to the body maintenance of high level phytoestrogens afterlong-term consumption of the crude drug.
The skin appeared to be healthy as shown to be shiny and firm in all volunteers after consu-mption of the crude drug. Its response to P.mirifica
Phytoestrogens was mediated by increasing water retention, and fat and/or collagen fiver accumula-treatment. Such accumulation would definitely re-sult in increasing firmness in that particular tissue and organ. Interestingly, all volunteers expressed this type of estrogenic response and thus should imply that ERβ is present abundantly in the skin and this type of response is very unique for P.mirifica phytoestrogen treatment.
The acne previously existed before treat-ment, or was initiated as a result of the crude drug consumption, would disappear soon. This pheno-menon might be mainly due to the novel balance of estrogen as phytoestrogens from P.mirifica could competitively bind to ERα. It could show an antag-onistic effect to estrogen throung an increase in the degradation of estrogen and/or a decrease in the ac-tivity of estrogen. The influence of P.mirifica upon acne formation and clearance as clearly demonstrated in this study could be explained by the presence of high amount of phytoestrogens in this plant.
The completed 4 months tested volunteers showed normal total blood count and blood chemi-stry analysis results especially the kidney and liver function tests. The results revaled that the designed dosage of 200 mg/day with maximum 21 times/month of the crude drug derived from P.mirifca cultivar Wichai-III was not toxic to the human body espec-ially female, whereas the 3 months subchronic tox-icity test in rats also revealed that the blood chemi-stry might change mildly at the dose of 1,000 mg /kg BW while normal findings were reported at the dosage of 10 and 100 mg/kg BW45. This dose emp-loyed should be most likely an effective dose as it could eliminate some meno-pausal symptoms wit-hin the 1st month of the test period and of nearly all menopausal symptoms within the 4th month of the test period without any serious adverse effects. One of the most interesting points was that this crude drug treatment fully abolished all previous menopausal symptoms, except the amoenorrhea which was resolved in only one out of 3 volunteers. It might imply that the crude drug at the employed dosage might not be strong enough to help reco-vering of such symptoms. In the contrary, it might be an advantage to administer this crude drug as it could help recovering the main nenopausal sym-ptoms without or mildly affecting the initiation or renewal of mens-truation period in amenorrhoea. Further-more the reduction of the crde drug consu-mption to approximately half the dose of the pre-vious one and keeping on of one year resulted in full recovery of menopausal symptoms. It could be implied from this study that half the dose was enough to maintain the recovering status whereas the full dose was necessary to boost the recovering within a definite period which was found to be not longer than 4 months. Some recovering symptoms could even be observed since the end of the 1st month test period.
The body weights of 4 volunteers were found to increase slightly at the end of the test. This phenomeno might be related to the increase in appetite which was clearly recorded in one volun-teer. It might also be related to the recovering of the facial and body skin dryness and/or wrinkles in all volunteers that was most likely to be due mainly to the increase of dermal fat and oil accumulation.
The decreases of blood cholesterol in volu-nteers that were 13.5 and 17.0% reduction, might result from suppression of cholesterol biosynthetic in specific tissue or increasing degradation of blo-od cholesterol or increasing uptake of blood cho-lesterol at peripheral tissues. The decreasing in blo-od and lesterol level was also reported in a toxi-cology  In rats which was more marked in the male than fe-
male45. Our test results might open a new criterion to apply this phytoestrogen-rich herb to treat hy-percholesterolaemaia or even arthrosclerosis that is very common in aging population including meno-pausal women.
P.mirifica phytoestrogens also exhibited nervous response as the recorded frustration which happened in 4 cases, sleep disorder in 3 cases, and hot flushes in 3 cases, were fully recovered and re-placed by a better mood in those 4 cases, as well as better appetite in one case. These findings were hard to monitor. The elevation of mood in 4 cases contributed to the sign of better quality of life which was very important in menopausal women as stress from bad mood or frustration not only affected the subject itslf but also more or less affected nearby people. Although some minor adverse effects were found after consumption of the crude drug, such as backache in 1 case, some minor benefit effects were also found such as elimination of headache, rheumatism, itching, constipation and acne. These findings convinced that the crude drug could exhibit more benefit than adverse effects after consumption. For example, the vaginal and/or cervical secretion reported in one case was classified as adverse effect in one hand as it did not happen in the volunteer before the test, it might also be recognized as trophic effect in the other hand as it could help recovering from vaginitis and dyspareunia. The breast size increase was classified as adverse effect by the same criteria but this phenomenon might be recognized as a trophic effect as well, due to the fact that breast enlargement was the benefit criteria for cosmetic purpose.
P.mirifica cultivar Wichi-III contains sig-nificant amount of isoflavone as analyzed by high performance liquid chromatography. The 100g dried powder contains 169.1 mg total isoflavone whereas miroestrol, deoxymiroestrol and other minor chemi-cals are present in very small amount and can not be easily detected routinely by this method21-23,43. It was then deduced that isoflavones could at least be the main chemical marker in the crude drug, and part of the menopausal symptom recovering as observed in this study could result partially from the high isoflavone content in P.mirifica cultivar Wichai-III as it was demonstrated before in MCF-7 cell line that Isoflavone from P.mirifica could also exhibit estrogenic effects46.
Phytoestrogens can competitively bind to ERα in a premenopausal woman who still has sitnificant amount of estrogen. P.mirifica phytoestrogen suppl-ementation could result in reducing the risk of estrogen-related cancer in this group of woman. Sup-plementation of phytoestrogens including P. mirifica in menopausal women with trace amount of estrogen could be a natural choice for estrogen suppl-ementation in one hand. It may, in the other hand, increase the risk of estrogen-related cancer as found in estrogen supplementation, which is stronger on the other hand, due to the agonistic effects of phyto-estrogens which are nearly totally dominated in the absence of estrogen. Very low amount of phyto-estrogen supplementation especially genistein could promote supplementation especially genistein could promote the growth of human beast cancer cell in vitro47. In thes study, there was no volunteer who had breast cancer or any other cancer during the 4 or 12 months studied period. It may be reasonable to con-clude that P. mirifica cultivar Wichai-III crude drug at this dose may be in the high dosage level and thus ex-hibits mainly cytotoxic or neural but not trophic effect to the pre-existing breast cyst (if present). It also does not stimulate the occurrence of a new breast cyst. All animal treated with P.mirific or miroestrol, the key chemical of P.mirifica also exh-ibited no report of breast cancer occuring13,18-19,45, as well as the clinical trial with miroestrol20.
However, the number of the volunteers in this study is very small and thus may not be strong enough to conclude that P. mirifica can protect aga-inst breast cyst formation in menopausal women. It may be worth also testing the topical application of P. mirifica extract directly to the breast area whether it can protect against barest cancer or not if applied long term.
The number of menopausal women in cur-rently increasing in developed countries. ERT is at present the choice of effective treatment for such population. Phytoestrogen could be then a novel alternative as it could do both functions at the same time, exhibiting estrogenic effects as well as func-tioning as an anticancer agent. Previous studies have clearly indicated that the estrogenic effects of P. mirifica are far stronger than those of soy.whichi is a  popular commercialized natural phytoestrogen
supplementation at present .We can therefore stress that this study has initiated an attractive invitation
for researchers to investigate deeply in to P.mirifica
phytoestrogens and manipulate them to serve the need for alternative medicine or Phytoestrogen Re-with a reduced cancer risk which has been pre-viously seen in those taking soy phytoestrogens48, and with a higher degree of success in relieving menopausal symptoms.
ACKNOWLEDGEMENTS
The authors wish to thank Japan Food Re¬search Laboratory, Osaka Branch, Japan, for HPLC isoflavone analysis with the sample of White Kwao Krua, P. mirifica cultivar Wichai-III, to Ramathibodi Hospital, Mahidol University and the Office of Aca¬demic Affairs, Chulalongkorn University for partial support.

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