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Archives of Medical Science : AMS Jan 2019Many experimental and clinical trials have suggested that flaxseed might be a potent antihypertensive, but the evidence concerning the effects of flaxseed supplements on... (Review)
Review
INTRODUCTION
Many experimental and clinical trials have suggested that flaxseed might be a potent antihypertensive, but the evidence concerning the effects of flaxseed supplements on plasma C-reactive protein (CRP) concentrations has not been fully conclusive. We assessed the impact of the effects of flaxseed supplementation on plasma CRP concentrations through a systematic review of literature and meta-analysis of available randomised controlled trials (RCTs).
MATERIAL AND METHODS
The literature search included EMBASE, ProQuest, CINAHL, and PUBMED databases up to 1 February 2016 to identify RCTs investigating the effect of flaxseed supplements on plasma CRP concentrations. Meta-analysis was performed using a random-effects model, and effect size was expressed as weighed mean difference (WMD) and 95% confidence interval (CI).
RESULTS
Meta-analysis of 17 selected RCTs with 1256 individuals did not suggest a significant change in plasma CRP concentrations following supplementation with flaxseed-containing products (WMD: -0.25 mg/l, 95% CI: -0.53, 0.02, = 0.074). The effect size was robust in the leave-one-out sensitivity analysis. Subgroup analysis did not suggest any significant difference in terms of changing plasma CRP concentrations among different types of flaxseed supplements used in the included studies, i.e. flaxseed oil (WMD: -0.67 mg/l, 95% CI: -2.00, 0.65, = 0.320), lignan extract (WMD: -0.32 mg/l, 95% CI: -0.71, 0.06, = 0.103) and ground powder (WMD: -0.18 mg/l, 95% CI: -0.42, 0.06, = 0.142).
CONCLUSIONS
The meta-analysis of RCTs did not show a significant change in plasma CRP concentrations following supplementation with various flaxseed products. Large, well-designed studies should be still performed to validate the current results.
PubMed: 30697250
DOI: 10.5114/aoms.2018.81034 -
Journal of Ethnopharmacology Jun 2022Aconitum carmichaelii, belonging to the Ranunculaceae family, is a widely used traditional herbal plant in Asian countries, especially in China. The lateral ("Fuzi") and... (Review)
Review
Aconitum carmichaelii Debeaux: A systematic review on traditional use, and the chemical structures and pharmacological properties of polysaccharides and phenolic compounds in the roots.
ETHNOPHARMACOLOGICAL RELEVANCE
Aconitum carmichaelii, belonging to the Ranunculaceae family, is a widely used traditional herbal plant in Asian countries, especially in China. The lateral ("Fuzi") and mother ("Chuanwu") roots are the two main plant parts used in Traditional Chinese Medicine (TCM), where they are used in the treatment of acute myocardial infarction, heart failure, rheumatoid arthritis, and as analgesics.
AIM OF THE STUDY
In order to further guide the research direction and application of A. carmichaelii, this study aims to give a systematic and in-depth overview on the phytochemical and pharmacological studies of non-alkaloid natural products with focus on polysaccharides and phenolic compounds.
MATERIALS AND METHODS
A comprehensive search in the literature was conducted based on the databases Google Scholar, SciFinder (American Chemical Society), Springer Link, PubMed Science, Science Direct and China National Knowledge Internet, Wanfang Data, in addition to books, doctoral and master's dissertations, and official website. The main keywords were: "Aconitum carmichaelii", "Aconiti Lateralis Radix Praeparata", "Fuzi", "Chuanwu", "Aconiti Radix", "monkshood" and "Bushi".
RESULTS
A. carmichaelii is known for the use of its different root parts, including "Fuzi" and "Chuanwu". Different types of polysaccharides, both neutral and acidic, and 39 phenolic compounds like flavonoids, phenylpropanoids, lignans, neolignans, and benzoic acid derivatives have been isolated and identified from the roots. Pharmacological studies of the isolated polysaccharides have demonstrated various biological effects such as hypoglycemic, hypolipidemic, cardiovascular, immunomodulatory, anti-tumor, and neuropharmacological activities. Studies on pharmacological effects of the phenolic compounds isolated from the roots are however limited.
CONCLUSIONS
This review shows that polysaccharides could be one of the active components in the roots of A. carmichaelii, and they are promising for future applications due to their pharmacological properties. In addition, polysaccharides are generally non-toxic, biocompatible, and biodegradable. This review also sheds light on new research directions for A. carmichaelii. A more detailed structural characterization of polysaccharides from different root parts of A. carmichaelii, and their structure-activity relationships are required. Additionally, their pharmacological properties as immunomodulators in the intestinal system should be investigated. Further, more knowledge about the pharmacological effects and molecular mechanisms of the phenolic compounds that have been identified are needed.
Topics: Aconitum; Drugs, Chinese Herbal; Medicine, Chinese Traditional; Phenols; Phytochemicals; Plant Roots; Polysaccharides
PubMed: 35240238
DOI: 10.1016/j.jep.2022.115148 -
Clinical Nutrition (Edinburgh, Scotland) Jun 2016Many experimental and clinical trials suggested that flaxseed might be a potent antihypertensive, but the evidences concerning the effects of flaxseed supplements on... (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND & AIMS
Many experimental and clinical trials suggested that flaxseed might be a potent antihypertensive, but the evidences concerning the effects of flaxseed supplements on blood pressure (BP) has not been fully conclusive. We aimed to assess the impact of the effects of flaxseed supplements on blood pressure through systematic review of literature and meta-analysis of available randomized controlled trials (RCTs).
METHODS
The literature search included PUBMED, Cochrane Library, Scopus, and EMBASE up to February 2015 to identify RCTs investigating the effect of flaxseed supplements on plasma blood pressure. Effect size was expressed as weighed mean difference (WMD) and 95% confidence interval (CI).
RESULTS
15 trials (comprising 19 treatment arms) with 1302 participants were included in this meta-analysis. Random-effects meta-analysis suggested significant reductions in both systolic BP (SBP) (WMD: -2.85 mmHg, 95%CI: -5.37 to -0.33, p = 0.027) and diastolic BP (DBP) (WMD: -2.39 mmHg, 95%CI: -3.78 to -0.99, p = 0.001) following supplementation with flaxseed products. When the studies were stratified according to their duration, there was a greater effect on both SBP and DBP in the subset of trials with ≥12 weeks of duration (WMD: -3.10 mmHg, 95%CI: -6.46 to 0.27, p = 0.072 and -2.62 mmHg, 95%CI: -4.39 to -0.86, p = 0.003, respectively) vs the subset lasting <12 weeks (WMD: -1.60 mmHg, 95%CI: -5.44 to 2.24, p = 0.413, and -1.74 mmHg, 95%CI: -4.41 to 0.93, p = 0.202, respectively). Another subgroup analysis was performed to assess the impact of flaxseed supplement type on BP. Reduction of SBP was significant with flaxseed powder (WMD: -1.81 mmHg, 95% CI: -2.03 to -1.59, p < 0.001) but not oil (WMD: -4.62 mmHg, 95%CI: -11.86 to 2.62, p = 0.211) and lignan extract (WMD: 0.28 mmHg, 95% CI: -3.49 to 4.04, p = 0.885). However, DBP was significantly reduced with powder and oil preparations (WMD: -1.28 mmHg, 95% CI: -2.44 to -0.11, p = 0.031, and -4.10 mmHg, 95%CI: -6.81 to -1.39, p = 0.003, respectively), but not with lignan extract (WMD: -1.78 mmHg, 95% CI: -4.28 to 0.72, p = 0.162).
CONCLUSIONS
This meta-analysis of RCTs showed significant reductions in both SBP and DBP following supplementation with various flaxseed products.
Topics: Antihypertensive Agents; Dietary Supplements; Evidence-Based Medicine; Flax; Humans; Hypertension; Lignans; Linseed Oil; Plant Extracts; Randomized Controlled Trials as Topic; Reproducibility of Results; Seeds
PubMed: 26071633
DOI: 10.1016/j.clnu.2015.05.012 -
Current Topics in Medicinal Chemistry 2016Anxiety disorders are the most common mental illnesses affecting human beings. They range from panic to generalized anxiety disorders upsetting the well-being and... (Review)
Review
Anxiety disorders are the most common mental illnesses affecting human beings. They range from panic to generalized anxiety disorders upsetting the well-being and psychosocial performance of patients. Several conventional anxiolytic drugs are being used which in turn results in several adverse effects. Therefore, studies to find suitable safe medicines from natural sources are being conducted by researchers. The aim of the present study is to comprehensively review phytochemical compounds with well-established anxiolytic activities and their structure-activity relationships as well as neuropsychopharmacological aspects. Results showed that phytochemicals like; alkaloids, flavonoids, phenolic acids, lignans, cinnamates, terpenes and saponins possess anxiolytic effects in a wide range of animal models of anxiety. The involved mechanisms include interaction with γ-aminobutyric acid (GABA)A receptors at benzodiazepine (BZD) and non-BZD sites with various affinity to different subunits, serotonergic 5-hydrodytryptamine (5-HT)1A and 5-HT2A/C receptors, noradrenergic and dopaminergic systems, glycine and glutamate receptors, and κ-opioid receptor as well as cannabinoid (CB)1 and CB2 receptors. Phytochemicals also modulate the hypothalamo-pituitary-adrenal (HPA) axis, the levels of pro-inflammatory cytokines like interleukin (IL)-2, IL-6, IL-1β and tumor necrosis factor (TNF)-α, and improve brain derived neurotrophic factor (BDNF) levels. Transient receptor potential cation channel subfamily V (TRPV)3, nitric oxide cyclic guanosine monophosphate (NOcGMP) pathway and monoamine oxidase enzymes are other targets of phytochemicals with anxiolytic activity. Taking together, these phytochemicals may be considered as supplements to conventional anxiolytic therapies in order to improve efficacy and reduce adverse effects. Further preclinical and clinical studies are still needed in order to recognize the structure-activity relationships, metabolism, absorption, and neuropsychopharmacological mechanisms of plantderived natural agents.
Topics: Anxiety Disorders; Biological Products; Humans; Phytochemicals; Structure-Activity Relationship
PubMed: 26845556
DOI: 10.2174/1568026616666160204121039 -
Nutrients Apr 2017Epidemiologic studies have suggested an inverse association between flavonoids and cardiovascular disease (CVD). However, the results might have been influenced by the... (Review)
Review
Epidemiologic studies have suggested an inverse association between flavonoids and cardiovascular disease (CVD). However, the results might have been influenced by the use of dietary assessment methods, which are error prone. The aim of this paper was to systematically review and analyse the literature for evidence of associations between polyphenol biomarkers and CVD and mortality risk in observational studies. Eligible studies were identified through PubMed, Web of Science, and reference lists. Multivariable adjusted associations were extracted. Data were log-transformed and pooled using the random effects model. In total, eight studies were included, investigating 16 different polyphenol biomarkers in association with CVD and mortality. Blood and urine were used as biospecimens, and enterolactone, a lignan metabolite, was most often investigated. Three meta-analyses were conducted investigating the association between enterolactone, and all-cause and CVD mortality, and non-fatal myocardial infarction. A 30% and 45% reduced all-cause and CVD mortality risk were revealed at higher enterolactone concentrations. Furthermore, inverse associations were observed between polyphenol biomarkers and all-cause mortality, kaempferol, and acute coronary syndrome. There is evidence to suggest that enterolactone is associated with a lower CVD mortality risk. This emphasises the importance of the role of the microbiota in disease prevention. To strengthen the evidence, more studies are warranted.
Topics: Animals; Biomarkers; Cardiovascular Diseases; Food Analysis; Humans; Polyphenols
PubMed: 28441720
DOI: 10.3390/nu9040415 -
Nutrition Research (New York, N.Y.) Feb 2023Flaxseed is a functional food because of its high content of alpha-linolenic acid, lignans, and dietary fiber. We hypothesized that flaxseed supplementation would... (Meta-Analysis)
Meta-Analysis Review
Flaxseed is a functional food because of its high content of alpha-linolenic acid, lignans, and dietary fiber. We hypothesized that flaxseed supplementation would improve cardiometabolic parameters in patients with type 2 diabetes mellitus (T2DM); however, clinical trials have shown conflicting results. Therefore, this systematic review and meta-analysis was conducted to determine the impact of flaxseed supplementation in patients with T2DM. Randomized controlled trials were systematically searched in PubMed, Web of Science, Scopus, Cochrane Library, and Embase until 25 March 2022. A total of 13 studies were included, and the results showed that flaxseed supplementation significantly reduced hemoglobin A1c (HbA1c) in participants with T2DM compared with the control group. In contrast, it had no effects on body weight, body mass index, blood pressure, fasting blood glucose (FBG), homeostatic model assessment for insulin resistance, quantitative insulin sensitivity check index, and lipid parameters. In the subgroup analyses, FBG was significantly reduced with supplementation of flaxseed in participants with baseline FBG ≥8.0 mmol/L or baseline HbA1c ≥7.0%. And a significant decrease in HbA1c in participants with baseline HbA1c ≥7.0% after flaxseed supplementation. In addition, subgroup analyses indicated that whole flaxseed supplementation significantly increased high-density lipoprotein cholesterol and reduced total cholesterol or low-density lipoprotein cholesterol in participants with T2DM. In conclusion, flaxseed supplementation significantly reduced HbA1c in participants with T2DM, especially those with poorly controlled blood sugar levels. However, larger scale studies with better designs are needed to confirm insignificant and/or ambiguous findings.
Topics: Humans; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Flax; Dietary Supplements; Cholesterol; Blood Glucose
PubMed: 36640581
DOI: 10.1016/j.nutres.2022.12.008 -
Nutrition & Metabolism Oct 2021Flaxseed is widely used as a functional food for its rich sources of linolenic acid, lignans and dietary fibers in the world. This systematic review and dose-response... (Review)
Review
Comparisons of the effects of different flaxseed products consumption on lipid profiles, inflammatory cytokines and anthropometric indices in patients with dyslipidemia related diseases: systematic review and a dose-response meta-analysis of randomized controlled trials.
BACKGROUND
Flaxseed is widely used as a functional food for its rich sources of linolenic acid, lignans and dietary fibers in the world. This systematic review and dose-response meta-analysis on randomized controlled trials (RCTs) is first to evaluate effects of different flaxseed products (whole flaxseed, oil and lignans) on lipid profiles, inflammatory and anthropometric parameters in patients with dyslipidemia related diseases.
METHODS
Literature search was performed in PubMed, Embase, Cochrane Central, Scopus, and Web of Science from the inception dates to January, 2020. Weighted mean differences with the 95% confidence interval (CI) were pooled using fix or random-effects models.
RESULTS
Thirty-one RCTs involving 1,698 participants were included. The present meta-analysis revealed that flaxseed consumption had an overall beneficial effect on serum TC, LDL-C, TG, apo B and IL-6 in patients with dyslipidemia related diseases, but not on apo A, HDL-C, hs-CRP, CRP and anthropometric indices. However, different flaxseed products showed obviously different effects. Whole flaxseed supplementation significantly reduced TC (- 11.85 mg/dl, 95% CI - 20.12 to - 3.57, P = 0.005), LDL-C (- 10.51 mg/dl, 95% CI - 14.96 to - 6.06, P < 0.001), TG (- 19.77 mg/dl, 95% CI - 33.61 to - 5.94, P = 0.005), apolipoprotein B (- 5.73 mg/dl, 95% CI - 7.53 to - 3.93, P < 0.001), TC/HDL-C (- 0.10, 95% CI - 0.19 to - 0.003, P = 0.044) and weight (- 0.40 kg, 95% CI - 0.76 to - 0.05, P = 0.027); Lignans supplementation significantly reduced TC (- 17.86 mg/dl, P = 0.004), LDL-C (- 15.47 mg/dl, P < 0.001) and TC/HDL-C (- 0.45, P = 0.04). Although flaxseed oil supplementation had no such lowering-effect on lipid, meta-analysis revealed its lowering-effect on IL-6 (- 0.35 pg/ml, P = 0.033) and hs-CRP (- 1.54 mg/l, P = 0.004). Subgroup analysis revealed that whole flaxseed decreased TC, LDL-C and TG levels irrespective of country and the intervention time prescribed, but was more pronounced when the dose of whole flaxseed was ≤ 30 g/day (TC: WMD - 13.61 mg/mL; LDL-C: WMD - 10.52 mg/mL; TG: WMD - 23.52 mg/mL), rather not a dose > 30 g/day. Moreover, a linear relationship between dose of whole flaxseed and absolute changes in C-reactive protein (P = 0.036) and a nonlinear relationship between with IL-6 (P < 0.001) were detected.
CONCLUSIONS
Flaxseed intervention suggested the positive effects on lipid profiles, inflammatory cytokines and anthropometric indices in patients with dyslipidemia related diseases. Of these, whole flaxseed and lignans play an important role in reducing blood lipid, while flaxseed oil mainly plays in anti-inflammatory. Lipid- and weight-lowering was significant when whole flaxseed was consumed at doses < 30 mg/d, for lipid status with mixed dyslipidemia and patients with BMI > 25.
PubMed: 34635132
DOI: 10.1186/s12986-021-00619-3 -
International Journal of Clinical... Oct 2021Depression is one of the most common and specific symptoms among menopausal women, leading to significant personal, family, and economic burdens. Some studies have shown... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Depression is one of the most common and specific symptoms among menopausal women, leading to significant personal, family, and economic burdens. Some studies have shown that phytoestrogens can help relieve symptoms of depression.
OBJECTIVES
This systematic review and meta-analysis aim to assess the efficacy and safety of phytoestrogens in treating depression among menopausal women.
METHODS
A comprehensive search for relevant studies published until November 25, 2020, was conducted in PubMed, the Cochrane Library, Chinese Biomedical Literature Database, Web of Science, and EMBASE. Statistical analyses were performed with R 4.0.3.and Review Manager 5.4.
RESULTS
2183 studies were identified and 10 studies with 15 independent reports were included, involving 1248 participants. The quality of the four studies was assessed as high risk, six studies were assessed as unclear. The analyses conducted according random effects model indicated the significant positive effect on depressive symptoms for postmenopausal women compared with the placebo (SMD = -0.62; 95% CI = -1.13 to -0.12; Q = 45.62, df = 14, P < .01; I = 79%). The low dose phytoestrogens (25 mg/d ≤ dose ≤ 100 mg/d) have better effectiveness (SMD = -0.52; 95% CI = -0.85 to -0.20; I = 79%, P< .01) than high dose (dose > 100 mg/d) and ultralow dose (0 < dose < 25 mg/d), but showed no statistical significance (Q = 0.81 df = 2, P = .67). Isoflavones had better effectiveness (SMD = -0.48; 95% CI = -0.75 to 0.21; I = 75%, P < .01) than lignans of phytoestrogens (SMD = -0.22; 95% CI = -0.37 to 0.08; I = 0%, P = .96). The duration of intervention affects the efficacy of phytoestrogens (β = -0.03; 95% CI: [-0.05, 0.00]; P = .045). The effectiveness varies in regions. The adverse reactions frequently reported were gastrointestinal symptoms and cold or upper respiratory tract infection.
CONCLUSIONS
Phytoestrogen can relieve depression symptoms among menopausal, especially for postmenopausal women who take low doses(25 mg/d ≤ dose ≤ 100 mg/d) of phytoestrogens for a long-term duration. Although mild adverse reactions have been reported, phytoestrogen could be considered as a complementary treatment for postmenopausal depression.
Topics: Depressive Disorder; Female; Humans; Menopause; Perimenopause; Phytoestrogens; Postmenopause
PubMed: 33987926
DOI: 10.1111/ijcp.14360 -
Nutrition Reviews Jan 2021Recent studies have outlined the potential role of dietary factors in patients who have survived cancer. (Meta-Analysis)
Meta-Analysis
CONTEXT
Recent studies have outlined the potential role of dietary factors in patients who have survived cancer.
OBJECTIVE
The aim of this study was to summarize the evidence of the relation between dietary intake of phytoestrogens and their blood biomarkers and, overall, cancer-specific mortality and recurrence in patients with cancer.
DATA SOURCES
A systematic search of PubMed, EMBASE, and Web of Science databases of studies published up to September 2019 was performed. Databases were searched for prospective and retrospective cohort studies reporting on dietary phytoestrogen intake and/or blood biomarkers and the outcomes investigated.
DATA EXTRACTION
Data were extracted from each identified study using a standardized form.
DATA ANALYSIS
Twenty-eight articles on breast, lung, prostate, and colorectal cancer, and glioma were included for systematic review. Given the availability of studies, a quantitative meta-analysis was performed solely for breast cancer outcomes. A significant inverse association among higher dietary isoflavone intake, higher serum/plasma enterolactone concentrations, and overall mortality and cancer recurrence was found. Among other cancer types, 2 studies reported that higher serum enterolactone and higher intake of lignans were associated with cancer-specific survival for colorectal cancer and glioma, respectively.
CONCLUSIONS
Dietary phytoestrogens may play a role in survival from breast cancer ; evidence regarding other cancers is too limited to draw any conclusions.
Topics: 4-Butyrolactone; Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Diet; Eating; Female; Humans; Isoflavones; Lignans; Male; Middle Aged; Neoplasms; Phytoestrogens; Young Adult
PubMed: 32632445
DOI: 10.1093/nutrit/nuaa043 -
Journal of Ethnopharmacology May 2023Arctium lappa L., is a biennial plant that grows around the Eurasia. Many parts of Arctium lappa L. (roots, leaves and fruits, etc.) are medically used in different... (Review)
Review
ETHNOPHARMACOLOGICAL RELEVANCE
Arctium lappa L., is a biennial plant that grows around the Eurasia. Many parts of Arctium lappa L. (roots, leaves and fruits, etc.) are medically used in different countries. Arctium lappa L. fruit, also called Arctii Fructus, is traditionally applied to dispel wind-heat, ventilate lung to promote eruption, remove toxicity substance and relieve sore throat.
THE AIM OF THE REVIEW
The review aims to integrate the botany, ethnopharmacology, quality control, phytochemistry, pharmacology, derivatives and toxicity information of Arctii Fructus, so as to facilitate future research and explore the potential of Arctii Fructus as an agent for treating diseases.
MATERIALS AND METHODS
Related knowledge about Arctii Fructus were acquired from Science Direct, GeenMedical, PubMed, China National Knowledge Infrastructure (CNKI), Web of Science, Pharmacopoeia of the People's Republic of China, Doctoral and Master's thesis, ancient books, etc. RESULTS: Arctii Fructus as an herb used for medicine and food was pervasively distributed and applicated around the world. It was traditionally used to treat anemopyretic cold, dyspnea and cough, sore throat, etc. To date, more than 200 compounds have been isolated and identified from Arctii Fructus. It contained lignans, phenolic acids and fatty acids, terpenoids, volatile oils and others. Lignans, especially arctigenin and arctiin, had the extensive pharmacological effects such as anti-cancer, antiviral, anti-inflammatory activities. The ester derivatives of arctigenin had the anti-cancer, anti-Alzheimer's disease and immunity enhancing effects. Although Arctii Fructus extract had no toxicity, arctigenin was toxic at a certain dose. The alleviating effects of Arctii Fructus on chronic inflammation and ageing have been demonstrated by clinical studies.
CONCLUSION
Arctii Fructus is regarded as a worthy herb with many chemical components and various pharmacological effects. Several traditional applications have been supported by modern pharmacological research. However, their action mechanisms need to be further studied. Although many chemical components were isolated from Arctii Fructus, the current research mainly focused on lignans, especially arctiin and arctigenin. Therefore, it is very important to deeply clarify the pharmacological activities and action mechanism of the compounds and make full medicinal use of the resources of Arctii Fructus.
Topics: Humans; Ethnopharmacology; Fruit; Arctium; Lignans; Botany; Quality Control; Pharyngitis; Phytochemicals
PubMed: 36781057
DOI: 10.1016/j.jep.2023.116223