Effect of rhubarb (Rheum emodi) in primary dysmenorrhoea: a single-blind randomized controlled trial

Ethnobotanical Uses, Phytochemistry and Pharmacology of Different Rheum Species (Polygonaceae): A Review

Today, there is an increased tendency to use herbal remedies. Rhubarb refers to several species of the genus Rheum L. in the Polygonaceae family. This species-rich genus is mainly distributed in Asian countries. Several medicinal effects have been attributed to the Rheum spp. in the traditional and modern medicine such as healing lungs, liver, kidney, womb and bladder diseases, cancer, diabetes, insect bites, relapsing fevers, diarrhea and constipation. Various in vitro, in vivo and clinical studies have investigated the therapeutic effect of extracts, fractions and pure compounds isolated from different species of this genus. Considering the positive findings, several pharmaceutical formulations containing rhubarb extract like capsules, drops, mouthwashes and different topical formulations are now present in the market. However, there are other traditional therapeutic effects of rhubarb that have not been studied yet and it is of great importance to perform confirmatory experiments or clinical investigations. The current review summarizes general information regarding botany, phytochemistry, ethnobotany and pharmacological aspects of Rheum spp. It is hoped that the present review could motivate subsequent research on the other medicinal properties of these plants that have been neglected until today.

What we already know about rhubarb: a comprehensive review

Rhubarb (also named Rhei or Dahuang), one of the most ancient and important herbs in traditional Chinese medicine (TCM), belongs to the Rheum L. genus from the Polygonaceae family, and its application can be traced back to 270 BC in "Shen Nong Ben Cao Jing". Rhubarb has long been used as an antibacterial, anti-inflammatory, anti-fibrotic and anticancer medicine in China. However, for a variety of reasons, such as origin, variety and processing methods, there are differences in the effective components of rhubarb, which eventually lead to decreased quality and poor efficacy. Additionally, although some papers have reviewed the relationship between the active ingredients of rhubarb and pharmacologic actions, most studies have concentrated on one or several aspects, although there has been great progress in rhubarb research in recent years. Therefore, this review aims to summarize recent studies on the geographic distribution, taxonomic identification, pharmacology, clinical applications and safety issues related to rhubarb and provide insights into the further development and application of rhubarb in the future.

Effect of Chinese herbal medicine on primary dysmenorrhea: A protocol for a systematic review and meta-analysis

BACKGROUND

Primary dysmenorrhea (PD), the most common gynecological diseases, seriously affects women's life and work; however, without more effective treatment. Chinese herbal medicine (CHM) has been widely used for relieving dysmenorrheic pain in patients with PD. To assess the effectiveness and safety of CHM in patients with PD, a systematic review and meta-analysis of current published evidence regarding CHM as treatment for PD would be conducted in this study.

METHODS

Literatures related to CHM for PD from the establishment of the database to June 2019 will be retrieved from the following databases: MEDLINE, EMBACE, Wed of Science and Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, and Wanfang Database. There are no language restrictions for retrieving literature. Eligible randomized clinical trials (RCTs) evaluating the effectiveness and safety of CHM in PD patients will be put in the study including outcomes of pain intensity, clinical effectiveness rate, quality of life, and adverse events. By scanning the titles, abstracts and full texts, 2 reviewers will independently select studies, extract data, and assess the quality of study. Meta-analysis of RCTs will be conducted using Review Manager 5.1 software. The results will be presented as risk ratio for dichotomous data, and standardized or weighted mean difference for continuous data.

RESULT

This study will provide high-quality available evidence for the treatment of PD with CHM based on pain, clinical efficacy, quality of life, and adverse events.

CONCLUSION

The systematic review willto evaluate the efficacy of CHM in treating PD and provide evidence for clinicians.

PROSPERO REGISTRATION NUMBER

CRD42019121185.

Rheum australe, an endangered high-value medicinal herb of North Western Himalayas: a review of its botany, ethnomedical uses, phytochemistry and pharmacology

Rheum australe (Himalayan Rhubarb) is a multipurpose, endemic and endangered medicinal herb of North Western Himalayas. It finds extensive use as a medicinal herb since antiquity in different traditional systems of medicine to cure a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to treat various infectious diseases. The remedying properties of this plant species are ascribed to a set of diverse bioactive secondary metabolite constituents, particularly anthraquinones (emodin, chrysophanol, physcion, aloe-emodin and rhein) and stilbenoids (piceatannol, resveratrol), besides dietary flavonoids known for their putative health benefits. Recent studies demonstrate the pharmacological efficacy of some of these metabolites and/or their derivatives as lead molecules for the treatment of various human diseases. Present review comprehensively covers the literature available on R. australe from 1980 to early 2018. The review provides up-to-date information available on its botany for easy identification of the plant, and origin and historical perspective detailing its trade and commerce. Distribution, therapeutic potential in relation to traditional uses and pharmacology, phytochemistry and general biosynthesis of major chemical constituents are also discussed. Additionally, efficient and reproducible in vitro propagation studies holding vital significance in preserving the natural germplasm of the plant and for its industrial exploitation have also been highlighted. The review presents a detailed perspective for future studies to conserve and sustainably make use of this endangered plant species at a commercial scale.

Medicinal plants for primary dysmenorrhoea: A systematic review

OBJECTIVES

Primary dysmenorrhoea is a common complaint experienced by many females in their reproductive years. The use of medicinal plants in the treatment of various gynaecological conditions is on the increase, despite the limited evidence available regarding efficacy and safety of their use. The aim of this systematic review was to synthesise the most recent evidence relating to the treatment of primary dysmenorrhoea with medicinal plants.

METHODOLOGY

A thorough database search was conducted using defined search terms, and randomised controlled trials (RCTs) published in English between 2008 and 2016, pertaining to the use of medicinal plants (single use) for the treatment of primary dysmenorrhoea, were assessed. Studies evaluating dysmenorrhoeal pain and associated symptoms as a primary or secondary outcome were considered and assessed by two reviewers independently of each other, using the JADAD scale and the Cochrane risk of bias tool,.

RESULTS

22 RCTs were included in the review; 9 were placebo-controlled trials and 13 were comparative studies to pharmacological treatment or nutritional supplements. Most of the evaluated medicinal plants showed evidence of efficacy in relieving menstrual pain in at least one RCT. The low or unclear quality of the majority of these studies however warrants caution in interpreting these results.

CONCLUSION

This review adds to the knowledge-base on the use of these medicinal plants in the treatment of primary dysmenorrhoea. Further research is needed before definitive conclusions can be made regarding the efficacy and safety of the use of these medicinal plants.

Effect of near-infrared rays on female menstrual pain in Korea

Most Korean women who experience menstrual pain have reported taking pain medicine and making use of complementary alternative therapies. However, because some interventions may cause side effects, more effective pain-relieving measures need to be identified. This study using a non-equivalent group design, evaluated the effects of near-infrared rays on dysmenorrhea among Korean women. The experimental group wore a near-infrared ray abdominal belt for the duration of one menstrual cycle until the end of the menstrual period, while the control group used hot packs. The level of menstrual pain, menstrual pain duration, and pain medicine use were measured. The menstrual pain, average menstrual pain duration, and use of analgesics were reduced in the near-infrared rays group. The results of this study indicate that the near-infrared ray LED belt was effective in reducing menstrual pain, menstrual pain duration compared to the use of analgesics in Korean women with dysmenorrhea. Therefore, near-infrared rays may be used to relieve menstrual pain and improve the quality of life of women with dysmenorrhea in Korea.

Effects of herbal medicine for dysmenorrhea treatment on accompanied acne vulgaris: a study protocol for a randomized controlled trial

Background

The incidence of preadolescent acne among women is increasing. Acne deteriorates the quality of life; conventional treatment options are limited and have not been effective against acne, particularly acne associated with menstruation. Despite evidence that acne associated with menstruation abnormalities naturally improves when menstruation recovers to normal, there have only been few studies on the effects of dysmenorrhea treatment on acne. Therefore- we designed this study to assess the effects of gyejibokryung-hwan (GBH) and dangguijagyag-san (DJS), which are widely used in dysmenorrhea treatment, on acne associated with menstruation cycle.

Methods

This is a protocol for a randomized, double-blind, parallel-group, placebo-controlled and multicenter trial. One hundred and sixteen participants with dysmenorrhea accompanied by acne vulgaris will be recruited at three centers and randomized into two groups, the herbal treatment group and placebo group. The participants will receive GBH or DJS based on pattern identification or placebo granules thrice daily for 8 weeks, with an 8-week follow up. The primary outcome will be the mean percentage change in the count of inflammatory acne lesions. The secondary outcomes would be based on dysmenorrhea numeric rating scale, verbal multidimensional scoring system for dysmenorrhea, acne numeric rating scale, investigator’s static global assessment scale of facial acne vulgaris, and safety testing. Adverse events will also be reported.

Discussion

The effects of GBH or DJS used in dysmenorrhea treatment on acne associated with the menstrual cycle will be evaluated. The findings of this trial will provide evidence regarding the effect of herbal medicine in improving acne vulgaris associated with menstruation in women.

Trial registration

Korean Clinical Trial Registry (http://cris.nih.go.kr; registration number: KCT0002259). Date of registration: March 10, 2017

Rhein and rhubarb similarly protect the blood-brain barrier after experimental traumatic brain injury via gp91phox subunit of NADPH oxidase/ROS/ERK/MMP-9 signaling pathway

Oxidative stress chiefly contributes to the disruption of the BBB following traumatic brain injury (TBI). The Chinese herbal medicine rhubarb is a promising antioxidant in treating TBI. Here we performed in vivo and in vitro experiments to determine whether rhubarb and its absorbed bioactive compound protected the BBB after TBI by increasing ZO-1 expression through inhibition of gp91phox subunit of NADPH oxidase/ROS/ERK/MMP-9 pathway. Rats were subjected to the controlled cortical impact (CCI) model, and primary rat cortical astrocytes were exposed to scratch-wound model. The liquid chromatography with tandem mass spectrometry method showed that rhein was the compound absorbed in the brains of CCI rats after rhubarb administration. The wet-dry weights and Evans blue measurements revealed that rhubarb and rhein ameliorated BBB damage and brain edema in CCI rats. Western blots showed that rhubarb and rhein downregulated GFAP in vitro. RT-PCR, immunohistochemistry, Western blot and dichlorodihydrofluorescein diacetate analysis indicated that rhubarb prevented activation of gp91phox subunit of NADPH oxidase induced ROS production, subsequently inhibited ERK/MMP-9 pathway in vivo and in vitro. Interestingly, rhein and rhubarb similarly protected the BBB by inhibiting this signaling cascade. The results provide a novel herbal medicine to protect BBB following TBI via an antioxidative molecular mechanism.

Dietary supplements for dysmenorrhoea

BACKGROUND

Dysmenorrhoea refers to painful menstrual cramps and is a common gynaecological complaint. Conventional treatments include non-steroidal anti-inflammatory drugs (NSAIDs) and oral contraceptive pills (OCPs), which both reduce myometrial activity (contractions of the uterus). A suggested alternative approach is dietary supplements. We used the term 'dietary supplement' to include herbs or other botanical, vitamins, minerals, enzymes, and amino acids. We excluded traditional Chinese medicines.

OBJECTIVES

To determine the efficacy and safety of dietary supplements for treating dysmenorrhoea.

SEARCH METHODS

We searched sources including the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, AMED, PsycINFO (all from inception to 23 March 2015), trial registries, and the reference lists of relevant articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of dietary supplements for moderate or severe primary or secondary dysmenorrhoea. We excluded studies of women with an intrauterine device. Eligible comparators were other dietary supplements, placebo, no treatment, or conventional analgesia.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, performed data extraction and assessed the risk of bias in the included trials. The primary outcomes were pain intensity and adverse effects. We used a fixed-effect model to calculate odds ratios (ORs) for dichotomous data, and mean differences (MDs) or standardised mean differences (SMDs) for continuous data, with 95% confidence intervals (CIs). We presented data that were unsuitable for analysis either descriptively or in additional tables. We assessed the quality of the evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods.

MAIN RESULTS

We included 27 RCTs (3101 women). Most included studies were conducted amongst cohorts of students with primary dysmenorrhoea in their late teens or early twenties. Twenty-two studies were conducted in Iran and the rest were performed in other middle-income countries. Only one study addressed secondary dysmenorrhoea. Interventions included 12 different herbal medicines (German chamomile (Matricaria chamomilla, M recutita, Chamomilla recutita), cinnamon (Cinnamomum zeylanicum, C. verum), Damask rose (Rosa damascena), dill (Anethum graveolens), fennel (Foeniculum vulgare), fenugreek (Trigonella foenum-graecum), ginger (Zingiber officinale), guava (Psidium guajava), rhubarb (Rheum emodi), uzara (Xysmalobium undulatum), valerian (Valeriana officinalis), and zataria (Zataria multiflora)) and five non-herbal supplements (fish oil, melatonin, vitamins B1 and E, and zinc sulphate) in a variety of formulations and doses. Comparators included other supplements, placebo, no treatment, and NSAIDs.We judged all the evidence to be of low or very low quality. The main limitations were imprecision due to very small sample sizes, failure to report study methods, and inconsistency. For most comparisons there was only one included study, and very few studies reported adverse effects. Effectiveness of supplements for primary dysmenorrhoea We have presented pain scores (all on a visual analogue scale (VAS) 0 to 10 point scale) or rates of pain relief, or both, at the first post-treatment follow-up. Supplements versus placebo or no treatmentThere was no evidence of effectiveness for vitamin E (MD 0.00 points, 95% CI -0.34 to 0.34; two RCTs, 135 women).There was no consistent evidence of effectiveness for dill (MD -1.15 points, 95% CI -2.22 to -0.08, one RCT, 46 women), guava (MD 0.59, 95% CI -0.13 to 1.31; one RCT, 151 women); one RCT, 73 women), or fennel (MD -0.34 points, 95% CI -0.74 to 0.06; one RCT, 43 women).There was very limited evidence of effectiveness for fenugreek (MD -1.71 points, 95% CI -2.35 to -1.07; one RCT, 101 women), fish oil (MD 1.11 points, 95% CI 0.45 to 1.77; one RCT, 120 women), fish oil plus vitamin B1 (MD -1.21 points, 95% CI -1.79 to -0.63; one RCT, 120 women), ginger (MD -1.55 points, 95% CI -2.43 to -0.68; three RCTs, 266 women; OR 5.44, 95% CI 1.80 to 16.46; one RCT, 69 women), valerian (MD -0.76 points, 95% CI -1.44 to -0.08; one RCT, 100 women), vitamin B1 alone (MD -2.70 points, 95% CI -3.32 to -2.08; one RCT, 120 women), zataria (OR 6.66, 95% CI 2.66 to 16.72; one RCT, 99 women), and zinc sulphate (MD -0.95 points, 95% CI -1.54 to -0.36; one RCT, 99 women).Data on chamomile and cinnamon versus placebo were unsuitable for analysis. Supplements versus NSAIDSThere was no evidence of any difference between NSAIDs and dill (MD 0.13 points, 95% CI -1.01 to 1.27; one RCT, 47 women), fennel (MD -0.70 points, 95% CI -1.81 to 0.41; one RCT, 59 women), guava (MD 1.19, 95% CI 0.42 to 1.96; one RCT, 155 women), rhubarb (MD -0.20 points, 95% CI -0.44 to 0.04; one RCT, 45 women), or valerian (MD points 0.62 , 95% CI 0.03 to 1.21; one RCT, 99 women),There was no consistent evidence of a difference between Damask rose and NSAIDs (MD -0.15 points, 95% CI -0.55 to 0.25; one RCT, 92 women).There was very limited evidence that chamomile was more effective than NSAIDs (MD -1.42 points, 95% CI -1.69 to -1.15; one RCT, 160 women). Supplements versus other supplementsThere was no evidence of a difference in effectiveness between ginger and zinc sulphate (MD 0.02 points, 95% CI -0.58 to 0.62; one RCT, 101 women). Vitamin B1 may be more effective than fish oil (MD -1.59 points, 95% CI -2.25 to -0.93; one RCT, 120 women). Effectiveness of supplements for secondary dysmenorrhoea There was no strong evidence of benefit for melatonin compared to placebo for dysmenorrhoea secondary to endometriosis (data were unsuitable for analysis). Safety of supplements Only four of the 27 included studies reported adverse effects in both treatment groups. There was no evidence of a difference between the groups but data were too scanty to reach any conclusions about safety.

AUTHORS' CONCLUSIONS

There is no high quality evidence to support the effectiveness of any dietary supplement for dysmenorrhoea, and evidence of safety is lacking. However for several supplements there was some low quality evidence of effectiveness and more research is justified.