Evidence for an Aneugenic Mechanism of Action for Micronucleus Induction by Black Cohosh Extract.

Black cohosh extract (BCE) is a popular botanical dietary supplement marketed to relieve symptoms of various gynecological ailments. Studies conducted by the National Toxicology Program (NTP) showed that BCE induces micronucleated erythrocytes in female rats and mice. Subsequently, the NTP showed that a variety of BCEs, including the sample that induced micronuclei (MN) in vivo ("NTP BCE") had a similar effect in human TK6 cells. Further testing with the MultiFlow® DNA Damage Assay revealed that TK6 cells exposed to NTP BCE, as well as a BCE reference material (BC XRM), exhibited a signature consistent with aneugenic activity in TK6 cells. Results from experiments reported herein confirmed these in vitro observations with NTP BCE and BC XRM. We extended these studies to include a novel test system, the MultiFlow Aneugen Molecular Mechanism Assay. For these experiments, TK6 cells were exposed to NTP BCE and BC XRM over a range of concentrations in the presence of fluorescent Taxol (488 Taxol). After 4 h, nuclei from lysed cells were stained with a nucleic acid dye and labeled with fluorescent antibodies against phospho-histone H3 (p-H3) and Ki-67. Whereas BCEs did not affect p-H3:Ki-67 ratios (a signature of aneugenic mitotic kinase inhibitors), 488 Taxol-associated fluorescence (a tubulin binder-sensitive endpoint) was affected. More specifically, 488 Taxol-associated fluorescence was reduced over the same concentration range that was previously observed to induce MN. These results provide direct evidence that BCEs destabilize microtubules in vitro, and this is the molecular mechanism responsible for the aneugenicity findings. Environ. Mol. Mutagen. 2019. © 2019 The Authors. Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.

Efficacy and safety of remifemin on peri-menopausal symptoms induced by post-operative GnRH-a therapy for endometriosis: a randomized study versus tibolone.

BACKGROUND: The aim of this study was to investigate clinical efficacy and safety of Remifemin on peri-menopausal symptoms in endometriosis patients with a post-operative GnRH-a therapy. MATERIAL AND METHODS: We treated 116 women who had endometriosis with either Remifemin (n=56) 20 mg bid po or Tibolone (n=60) 2.5 mg qd po for 12 weeks after GnRH-a injection. The efficacy was evaluated by Kupperman menopausal index (KMI), and hot flash/sweating scores. The safety parameters such as liver and renal functions, lipid profile, endometrial thickness, and serum sex hormone level, as well as the incidence of adverse events were recorded. RESULTS: (1) After GnRH-a therapy, KMI and hot flash/sweating scores in both groups increased significantly (P<0.05) but we found no significant difference for KMI (2.87±1.40 for Remifemin and 2.70±1.26 for Tibolone) and hot flash/sweating scores (0.94±1.72 for Remifemin and 1.06±1.78 for Tibolone) between the 2 groups (P>0.05). (2) No statistical change was observed in liver or renal functions and lipid profile in both groups before and after the treatment (P>0.05). The post-therapeutic serum FSH, LH, and E2 level and endometrial thickness decreased remarkably in both groups (P<0.05). E2 level in the Remifemin group was obviously lower than that in the Tibolone group (P<0.05), and FSH and LH levels were strongly higher (P<0.05). No significant difference in thickness were found in either group (P>0.05). The Remifemin group had far fewer adverse events than the Tibolone group (P<0. 05). CONCLUSIONS: Compared with Tibolone, Remifemin had a similar clinical efficacy and was safer for the peri-menopausal symptoms induced by GnRH-a in endometriosis patients.

Black cohosh and breast cancer: a systematic review.

BACKGROUND: Many women use black cohosh as a natural treatment for menopausal symptoms. However, controversy exists around safety in breast cancer, because of its purported estrogenic activity. We conducted a systematic review of black cohosh use in women with or at risk of breast cancer. METHODS: We searched MEDLINE, Embase, the Cochrane Library, and AMED from inception to July 2012 and October 2012 for human interventional or observational data pertaining to the safety and efficacy of black cohosh in patients with or at risk of breast cancer, including an assessment of the effect of black cohosh on estrogen responsive tissues. RESULTS: Of 450 records, we included 26 articles: 14 randomized controlled trials, 7 uncontrolled trials, and 5 observational studies.The evidence on efficacy for ho t flashes is divided, with some benefits seen when compared with baseline, but not when compared with placebo. Two observational studies found no association between black cohosh and risk of breast cancer, whereas 2 studies reported significant reductions in risk of primary breast cancer among postmenopausal women (adjusted odds ratio = 0.47, 95% confidence interval = 0.27-0.82), and risk of recurrence (adjusted hazard ratio = 0.75, 95% confidence interval = 0.63-0.89). Seventeen trials showed no significant impact on circulating hormone levels or proliferation in estrogen responsive tissues. CONCLUSIONS: Current evidence does not support an association between black cohosh and increased risk of breast cancer. There is a lack of evidence supporting the efficacy of black cohosh for reduction of hot flashes in breast cancer patients. Given conflicting but promising results, and apparent safety, further research is warranted.

The effects of commercial preparations of herbal supplements commonly used by women on the biotransformation of fluorogenic substrates by human cytochromes P450.

The study set out to determine the potential for commercially available preparations of black cohosh (Actaea racemosa), chaste tree berry (Vitex agnus-castus), crampbark (Viburnum opulus) and false unicorn (Chamaelirium luteum) to inhibit the major human drug metabolizing enzymes CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4 as well as CYP1A1 which activates some carcinogens. In vitro microplate-based assays using cDNA-expressed CYP450 isoforms and fluorogenic substrates were used. Components of the commercial herbal preparations interfered with the assays and limited the concentration ranges that could be tested. Nevertheless, the fluorogenic assays were robust, reproducible and easy to perform and thus are still useful for initial screening for potential herb-drug interactions. None of the preparations affected CYPs 1A1 or 2C9 at the concentrations tested but all preparations inhibited some of the enzymes with potencies around 1 µg/mL. The three most potent interactions were: chaste tree berry and CYP2C19 (IC50) 0.22 µg/mL); chaste tree berry and CYP3A4 (IC50) 0.3 µg/mL); black cohosh and CYP2C19 (IC50) 0.37 µg/mL,). Thus, the study successfully identified the potential for the commercial herbal preparations to inhibit human drug metabolizing enzymes. Whether this potential translates into clinically significant herb-drug interactions can only be confirmed by appropriate in vivo studies.

Rapid screening of commercially available herbal products for the inhibition of major human hepatic cytochrome P450 enzymes using the N-in-one cocktail.

Self-administration of complementary products concurrently with conventional medication is increasingly common. The potential for cytochrome P450 (CYP) inhibition requires investigation. The N-in-one assay with ten probe substrates for nine CYPs was used with human liver microsomes to investigate ten products. CYP inhibition was measured in a single liquid chromatography-tandem mass spectrometry (LC/MS-MS) analysis. Estimated IC(50)-values were determined for the extracts that produced significant inhibition (less than 100 microg ml(-1)). Inhibition of CYP2C19 by dong quai (IC(50) = 13.7-14.3 microg ml(-1) for the methanolic extract) and CYP2D6 by goldenseal (IC(50) = 6.7 and 6.3 microg ml(-1) for the aqueous and methanolic extracts, respectively), are of particular concern as the potential for adverse interactions is high. The inhibition of CYP2C8 by horsetail (IC(50) = 93 microg ml(-1) for the aqueous extract) requires further investigation, as the potential for concurrent use with products that require CYP2C8 for metabolism is significant. CYP3A4 inhibition varied depending on the probe reaction being monitored. The earlier reported findings of inhibition by black cohosh, goldenseal and gotu kola were confirmed. The present work has shown that the N-in-one cocktail is a rapid and reliable method that can be used as an initial screen to help prioritize products that require more detailed investigations and it can also be applied to monitor product variability.

[Efficacy and safety of remifemin compared to tibolone for controlling of perimenopausal symptoms].

OBJECTIVE: To investigate the efficacy and safety of remifemin (isopropanolic extract of cimicifuga racemosa) treating perimenopausal symptoms in comparison of tibolone. METHODS: One hundred and eighty postmenopausal women at range of 40 - 60 years old were enrolled in a multicenter, randomized and double blind study. They were divided into remifemin and tibolone group at ratio 1:1. The therapeutic strategy was remifemin 20 mg bid po for 12 weeks in remifemin group and tibolone 2.5 mg qd po for 12 weeks in tibolone group. To evaluate therapeutic effect, total score of Kupperman menopause index (KMI) was used as the major observed index and single item score of KMI were secondary observed index. Safety warning was determined by laboratory tests and adverse events at timepoint of before, at 4 and 12 weeks treatment. RESULTS: (1) Total score of KMI: it were 24 +/- 5 in remifemin group and 25 +/- 6 in tibolone group before treatment. At timepoint of 4 weeks treatment, it were 11 +/- 6 in remifemin group and 11 +/- 7 in tibolone group. At timepoint of 12 weeks treatment, it were 7 +/- 6 in remifemin group and 6 +/- 5 in tibolone group. Total KMI score between two groups did not show statistical difference at various timepoint (P > 0.05). (2) Single item score of KMI: when compared before, at 4 and 12 weeks treatment, did show remarkable difference (P < 0.05) either in remifemin or in tibolone group. However, those single items of KMI score did not show statistical difference between 4 and 12 weeks timepoint in each treatment group (P > 0.05). (3) Adverse effect: the incidence of adverse effect in remifemin group was significantly lower than that of tibolone group. None case with vaginal bleeding was observed in remifemin group, however, 17 cases with vaginal bleeding occurred in tibolone group (19%, 17/90). The incidence of breast swelling were 16% (14/90) in remifemin group and 36% (32/90) in tibolone group; before treatment, the thickness of endometrium were (2.6 +/- 1.1) mm in remifemin group and (2.8 +/- 1.1) mm in tibolone group; at timepoint of 12 weeks treatment, the thickness of endometrium were (2.9 +/- 1.4) mm in remifemin group and (3.4 +/- 2.0) mm in tibolone group. In comparison of thickness of endometrium before and at 12 weeks treatment, no remarkable changes was observed in remifemin group, however, endometrium displayed significantly thicker in tibolone group. CONCLUSIONS: Our study suggested that remifemin was one effective and safe agent to manage women with climacteric symptom. It has similar therapeutic effect and lower incidence of adverse effect when compared with tibolone.

Black cohosh hepatotoxicity: quantitative causality evaluation in nine suspected cases.

OBJECTIVE: Black cohosh (BC), synonym for Actaea racemosa and Cimicifuga racemosa, is a herbal remedy for the treatment of menopausal symptoms. Recently, worldwide discussions have emerged as to whether its use maybe associated with the risk of rare hepatotoxicity in a few susceptible women. METHODS: We have evaluated the causal relationship in nine cases with suspected hepatotoxicity by the use of BC. The updated Council for International Organizations of Medical Sciences scale was used to quantitatively assess the causality for BC. RESULTS: In eight of nine patients with liver disease, causality for BC +/- comedication was excluded (n = 4) or unlikely (n = 4). The failure to ascribe causality in these cases was mainly due to alternative diagnosis, missing temporal association and dechallenge, and presentation of low quality data. In only one case, causality was possible for a BC preparation of an unknown brand taken for 2 months with an unknown daily dose. Confounding factors in this case include symptomatic cholelithiasis and fatty liver. Comedication with synthetic drugs and herbal or other dietary supplements was reported in five of nine patients. CONCLUSIONS: In nine cases of patients with liver disease, causality for BC +/- comedication was possible (n = 1), unlikely (n = 4), or excluded (n = 4). Due to this lack of significant circumstantial evidence, the present study shows little, if any, hepatotoxic risks by the use of BC in the analyzed cases.

An isopropanolic extract of black cohosh does not increase mammographic breast density or breast cell proliferation in postmenopausal women.

OBJECTIVE: The aim of this study was to determine the effects of the isopropanolic extract of black cohosh (Remifemin) on mammographic breast density and breast epithelial proliferation in healthy, naturally postmenopausal women with climacteric symptoms. DESIGN: This was a prospective, open, uncontrolled drug safety study in which baseline status was compared with status after 6 months of treatment by blinded observers. A total of 74 women were treated with 40 mg black cohosh daily, and 65 women completed the study. Mammograms were performed, and breast cells were collected by percutaneous fine needle aspiration biopsies at baseline and after 6 months. Mammographic density was quantified according to the Wolfe classification or a percentage scale. Breast cell proliferation was assessed using the Ki-67/MIB-1 monoclonal antibody. Safety was monitored by adverse event reporting, laboratory assessments, and measurement of the endometrium by vaginal ultrasound. RESULTS: None of the women showed any increase in mammographic breast density. Furthermore, there was no increase in breast cell proliferation. The mean change +/- SD in proportion of Ki-67-positive cells was -0.5% +/- 2.4% (median, 0.0; 95% CI = -1.32 to 0.34) for paired samples. The mean change in endometrial thickness +/- SD was 0.0 +/- 0.9 mm (median, 0.0). A modest number of adverse events were possibly related to treatment, but none of these were serious. Laboratory findings and vital signs were normal. CONCLUSIONS: The findings suggest that the isopropanolic extract of black cohosh does not cause adverse effects on breast tissue. Furthermore, our data do not indicate to any endometrial or general safety concerns during 6 months of treatment.

Cutaneous pseudolymphoma induced by Cimicifuga racemosa.

We report a 56-year-old female patient who presented with asymptomatic, localized erythematous plaques on arms and legs. Histologically, the diagnosis of pseudolymphoma (PL) was confirmed. Because of menopausal complaints, the patient had been taking Remifemin(R), a phytotherapeutical agent containing a standardized extract of black cohosh (Cimicifuga racemosa) rhizome for 1 year. Six months after initial administration of this herbal drug, first skin lesions appeared which continuously increased. Withdrawal of Remifemin resulted in regression and complete remission of the lesions within 12 weeks. To the best of our knowledge, this is the first report on cutaneous PL induced by a standardized extract of C. racemosa rhizoma. Thus, though claimed to be poor in adverse effects, the potency of phytotherapeutical agents to induce uncommon cutaneous eruptions needs to be taken into careful reconsideration since the course of cutaneous PL tends to be chronic and indolent if the causative agent is not discontinued.

Black cohosh (Actaea/Cimicifuga racemosa): review of the clinical data for safety and efficacy in menopausal symptoms.

Since the publication of the results of the Women's Health Initiative that described the risks of hormone replacement therapy, many women are actively seeking alternative treatments for menopausal symptoms. Black cohosh (Actaea racemosa, syn. Cimicifuga racemosa) is one such alternative that has been used in the US for over 100 years. To date only two cimicifuga extracts have been tested clinically, and the current recommended dosage is 40-80 mg/day. Review of the published clinical data suggests that cimicifuga may be useful for the treatment of menopausal symptoms, such as hot flashes, profuse sweating, insomnia, and anxiety. However, the methodology used in most of the trials is poor and further clinical assessment of cimicifuga is needed. In terms of safety, transient adverse events such as nausea, vomiting, headaches, dizziness, mastalgia, and weight gain have been observed in clinical trials. A few cases of hepatotoxicity have been reported, but a direct association with the ingestion of cimicifuga has not been demonstrated. The most recent data suggest that cimicifuga is not estrogenic.

The safety of black cohosh (Actaea racemosa, Cimicifuga racemosa).

Black cohosh (Actaea racemosa/Cimicifuga racemosa) is a North American perennial plant that has been used for traditional medicinal purposes by the native Indian population. Its modern day application is the treatment of menopausal symptoms. Unlike conventional non-herbal medications, herbal preparations have not been systematically evaluated for their safety. However, the evidence from in vitro, animal and clinical studies all suggest that black cohosh is a safe herbal therapy for menopausal women if taken for a limited period. More research is needed to evaluate the safety of this herb over longer periods of time, and also to further investigate its mechanism of action.

Autoimmune hepatitis associated with the use of black cohosh: a case study.

Herbal remedies generate more than 1.8 billion dollars in annual sales in the United States. Herbal products have been associated with a wide spectrum of hepatic toxicities. With the recent Women's Health Initiative Study demonstrating increased risk of breast cancer and cardiovascular events associated with hormone therapy, many women may resort to herbal remedies for persistent menopause symptoms. We report a case of autoimmune hepatitis likely triggered by the use of black cohosh (Actaea racemosa), an agent marketed to treat menopause symptoms. Given this case report, we recommend close monitoring of women using this herbal preparation.

Black cohosh: an alternative therapy for menopause?

Due to the long-term health risks now associated with hormone replacement therapy, many menopausal women are actively seeking alternative treatments. One such alternative is black cohosh (Actaea racemosa, syn. Cimicifuga racemosa), which has been used in the United States for the treatment of gynecologic complaints for more than 100 years. Review of the published clinical data suggests that black cohosh may be useful for the treatment of menopausal symptoms, such as hot flashes, profuse sweating, insomnia, and anxiety. Results from the most recently published trial, however, indicate that black cohosh is not effective for the treatment of menopausal symptoms in breast cancer survivors being treated with tamoxifen. Because the overall quality of the published clinical trials is low, two new randomized, double-blind, placebo-controlled clinical trials are currently underway in the United States. To date, only one standardized black cohosh extract has been tested clinically; the current recommended dose is 40-80 mg per day. At least 4-12 weeks of treatment may be required before any therapeutic benefits may be apparent. Adverse reactions such as nausea, vomiting, headaches, dizziness, mastalgia, and weight gain have been observed in clinical trials. No drug interactions are reported in the medical literature. The estrogenic effects of black cohosh are controversial, and the more recent data indicate that black cohosh extracts may have an anti-estrogenic activity. Owing to potential effects on sex hormones, however, black cohosh should not be administered to children or during pregnancy and lactation.