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Antioxidants (Basel, Switzerland) Oct 2023Osteoporosis is a condition favored by the postmenopausal decline in estrogen levels and worsened by oxidative stress (OS). Polyphenols are natural compounds abundantly... (Review)
Review
Osteoporosis is a condition favored by the postmenopausal decline in estrogen levels and worsened by oxidative stress (OS). Polyphenols are natural compounds abundantly found in fruits and vegetables, and they exert antioxidant and hormonal effects that could be useful in osteoporosis prevention, as suggested by epidemiological studies showing a lower incidence of fractures in individuals consuming polyphenol-rich diets. The aim of our meta-analysis is to evaluate the effects of polyphenols on bone mineral density (BMD, primary endpoint) and bone turnover markers (BTMs, secondary endpoint) in postmenopausal women. Twenty-one randomized control trials (RCTs) were included in our analysis after in-depth search on PubMed, EMBASE, and Scopus databases. We found that supplementation with polyphenols for 3-36 months exerted no statically significant effects on BMD measured at lumbar spine (sMD: 0.21, 95% CI [-0.08 to 0.51], = 0.16), femoral neck (sMD: 0.16, 95% CI [-0.23 to 0.55], = 0.42), total hip (sMD: 0.05, 95% CI [-0.14 to 0.24], = 0.61), and whole body (sMD: -0.12, 95% CI [-0.42 to 0.17], = 0.41). Subgroup analysis based on treatment duration showed no statistical significance, but a significant effect on lumbar BMD emerged when studies with duration of 24 months or greater were analyzed separately. On the other hand, we found a significantly slight increase in bone-specific alkaline phosphatase (BALP) levels (sMD: 1.27, 95% CI [1.13 to 1.42], < 0.0001) and a decrease in pyridinoline (PD) levels (sMD: -0.58, 95% CI [-0.77 to -0.39], < 0.0001). High heterogeneity among studies and unclear risk of bias in one third of the included studies emerged. A subgroup analysis showed similar effects for different duration of treatment and models of dual-energy X-ray absorptiometry (DXA) scanner. More robust evidence is needed before recommending the prescription of polyphenols in clinical practice.
PubMed: 37891909
DOI: 10.3390/antiox12101830 -
Frontiers in Nutrition 2023This study is the first systematic review and meta-analysis based on RCTs on the effects of anthocyanins on patients with type 2 diabetes mellitus (T2DM) and the effect...
Effects of anthocyanin supplementation in diet on glycemic and related cardiovascular biomarkers in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials.
PURPOSE
This study is the first systematic review and meta-analysis based on RCTs on the effects of anthocyanins on patients with type 2 diabetes mellitus (T2DM) and the effect on T2DM-related cardiovascular disease.
METHODS
RCTs published in English from five electronic databases were evaluated for glycated hemoglobin (HbA), fasting blood glucose (FBG), 2-h postprandial blood glucose, fasting insulin, model assessment for insulin resistance, triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, systolic blood pressure, and diastolic blood pressure. The quality of the studies was rated (Cochrane Risk of Bias tool) and weighted mean differences were calculated (DerSimonian-Laird model with random effects). Leave-one-out sensitivity, subgroup, and publication bias analyses were conducted. The strength of the evidence was rated according to the GRADE guidelines.
RESULTS
In all, 13 RCTs were analyzed out of the 239 identified studies, with a duration longer than 4 weeks (703 participants with T2DM). Our findings indicate that a median dose of 320 mg/day anthocyanins, either from fruit extracts or pure supplements, for a median intervention length of 8 weeks significantly reduced HbA [Weighted Mean Difference (WMD) -0.31, = 0.00], FBG (WMD -0.63, = 0.00), 2-h postprandial glucose (WMD -1.60, = 0.00), TG (WMD -0.45, = 0.01), and LDL (WMD -0.26 = 0.02). However, the effects of anthocyanins on fasting insulin, HOMA-IR, TC, HDL cholesterol, systolic blood pressure, and diastolic blood pressure in patients with T2DM were not statistically significant. Anthocyanins from fruit extracts or powder exhibited a higher reduction of HbA compared to pure anthocyanin supplements.
CONCLUSION
The significant improvements in glycemic parameters and lipid profile, suggest the benefits of anthocyanins, especially from fruit extract or powder, in the management of T2DM, and their ability to delay the onset of lipid disorder-related diseases such as cardiovascular disease associated with T2DM. The mechanism behind this reduction in glycemic markers could be attributed to the antioxidant and anti-inflammatory activity of anthocyanins. Further research with well-designed RCTs is required to determine the optimal dosage of anthocyanins for the treatment of T2DM and to comprehend the consequences.
PubMed: 37810926
DOI: 10.3389/fnut.2023.1199815 -
Frontiers in Pharmacology 2023Resveratrol, a polyphenol found in various plants, is known for its diverse bioactivities and has been explored in relation to nonalcoholic fatty liver disease (NAFLD)....
Resveratrol, a polyphenol found in various plants, is known for its diverse bioactivities and has been explored in relation to nonalcoholic fatty liver disease (NAFLD). However, no high-quality evidence exists regarding its efficacy. a meta-analysis was conducted to evaluate the potential efficacy of resveratrol in treating nonalcoholic fatty liver disease by analyzing both preclinical studies and clinical trials. PubMed, Embase and Web of Science were searched for the included literature with the criteria for screening. Quantitative synthesis and meta-analyses were performed by STATA 16.0. Twenty-seven studies were included, and the results indicated that resveratrol effectively improved liver function, reduced fatty liver indicators, and affected other indices in preclinical studies. The effective dosage ranged from 50 mg/kg-200 mg/kg, administered over a period of 4-8 weeks. While there were inconsistencies between clinical trials and preclinical research, both study types revealed that resveratrol significantly reduced tumor necrosis factor-α levels, further supporting its protective effect against nonalcoholic fatty liver disease. Additionally, resveratrol alleviated nonalcoholic fatty liver disease primarily via AMPK/Sirt1 and anti-inflammatory signaling pathways. Current meta-analysis could not consistently verify the efficacy of resveratrol in treating nonalcoholic fatty liver disease, but demonstrated the liver-protective effects on nonalcoholic fatty liver disease. The large-sample scale and single region RCTs were further needed to investigate the efficacy.
PubMed: 37767399
DOI: 10.3389/fphar.2023.1230783 -
Nutrients Sep 2023Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, bloating, and changes in bowel habits. Various dietary factors... (Review)
Review
BACKGROUND
Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, bloating, and changes in bowel habits. Various dietary factors have been implicated in the pathogenesis and management of IBS symptoms. This systematic review aims to evaluate the effects of polyphenols, minerals, fibers, and fruits on the symptoms and overall well-being of individuals with IBS.
MATERIALS AND METHODS
A comprehensive literature search was conducted in several electronic databases, including PubMed, Scopus, and Web of Science. Studies published up until July 2023 were included.
RESULTS
The selected studies varied in terms of study design, participant characteristics, intervention duration, and outcome measures. Overall, the findings suggest that dietary interventions involving polyphenols, minerals, fibers, and fruits can have a positive impact on IBS symptoms. Dietary fiber supplementation, particularly soluble fiber, has been associated with reduced bloating and enhanced stool consistency.
CONCLUSIONS
This systematic review provides evidence supporting the beneficial effects of polyphenols, minerals, fibers, and fruits in IBS patients. These dietary components hold promise as complementary approaches for managing IBS symptoms. However, due to the heterogeneity of the included studies and the limited number of high-quality randomized controlled trials, further well-designed trials are warranted to establish the optimal dosages, duration, and long-term effects of these interventions. Understanding the role of specific dietary components in IBS management may pave the way for personalized dietary recommendations and improve the quality of life for individuals suffering from this complex disorder.
Topics: Humans; Fruit; Polyphenols; Irritable Bowel Syndrome; Quality of Life; Minerals; Flatulence
PubMed: 37764853
DOI: 10.3390/nu15184070 -
ACS Omega Sep 2023Excessive UV radiation (UVR) exposure has been shown in studies to be a major risk factor for most melanomas, causing premature skin aging as well as immune system... (Review)
Review
Excessive UV radiation (UVR) exposure has been shown in studies to be a major risk factor for most melanomas, causing premature skin aging as well as immune system suppression due to the increased production of hydrogen peroxide (HO) and other reactive oxygen species (ROS) during the melanogenesis process. Although several compounds with antioxidant and antityrosinase activities are widely used in the cosmetic industry, like kojic acid, hydroquinone, ascorbic acid, and arbutin, their use has been limited due to their adverse effects on the skin and cytotoxic issues. Recently, attempts have been made to develop new natural skin-lightening products by using plant extracts that are less toxic and exhibit numerous biological properties with great market demand. In this study, information on the depigmentation effects of various natural plant species was gathered from the SCOPUS database according to the PRISMA guidelines. A total of 414 records were retrieved, and finally, 76 articles were included in the qualitative synthesis by fulfilling all the inclusion criteria. In this review, we discuss the extraction methods and biological assays of 75 highly potential plant species, including the olive, yuzu, longan, and lotus. We concluded that the use of natural plants as skin-whitening agents is highly effective as there is a significant correlation between the content of polyphenolic compounds, antimelanogenesis, antityrosinase, and antioxidant activities. However, it is worth noting that the use of extraction methods or types of solvents is very important in determining the biological activities of plants.
PubMed: 37744793
DOI: 10.1021/acsomega.3c02994 -
Cancer Cell International Sep 2023Paclitaxel is a natural anticancer compound with minimal toxicity, the capacity to stabilize microtubules, and high efficiency that has remained the standard of... (Review)
Review
Paclitaxel is a natural anticancer compound with minimal toxicity, the capacity to stabilize microtubules, and high efficiency that has remained the standard of treatment alongside platinum-based therapy as a remedy for a variety of different malignancies. In contrast, polyphenols such as flavonoids are also efficient antioxidant and anti-inflammatory and have now been shown to possess potent anticancer properties. Therefore, the synergistic effects of paclitaxel and flavonoids against cancer will be of interest. In this review, we use a Boolean query to comprehensively search the well-known Scopus database for literature research taking the advantage of paclitaxel and flavonoids simultaneously while treating various types of cancer. After retrieving and reviewing the intended investigations based on the input keywords, the anticancer mechanisms of flavonoids and paclitaxel and their synergistic effects on different targets raging from cell lines to animal models are discussed in terms of the corresponding involved signaling transduction. Most studies demonstrated that these signaling pathways will induce apoptotic / pro-apoptotic proteins, which in turn may activate several caspases leading to apoptosis. Finally, it can be concluded that the results of this review may be beneficial in serving as a theoretical foundation and reference for future studies of paclitaxel synthesis, anticancer processes, and clinical applications involving different clinical trials.
PubMed: 37743502
DOI: 10.1186/s12935-023-03052-z -
Current Nutrition Reports Dec 2023Dietary patterns that include polyphenols may help manage cardiometabolic risk factors. Pigmented rice contains phenolic acids and flavonoids that contribute to its...
PURPOSE OF REVIEW
Dietary patterns that include polyphenols may help manage cardiometabolic risk factors. Pigmented rice contains phenolic acids and flavonoids that contribute to its antioxidant properties. This review examined the effect of polyphenol-containing pigmented rice on antioxidant status, lipid profile, glucose/insulin, blood pressure, and weight among adults. Four electronic databases including PubMed, ProQuest, EBSCOhost, and Google Scholar were systematically searched for relevant articles published in English since 2000, using PRISMA guidelines (PROSPERO registration: CRD42022358132). Two-staged screening resulted in the inclusion of seventeen (seven acute, ten chronic) randomized controlled trials. A random effects model was conducted on cardiometabolic outcomes reported in at least three studies.
RECENT FINDINGS
Acute intake increased plasma antioxidant activity and lowered postprandial glucose and insulin levels. Chronic consumption was associated with reductions in fasting glucose (WMD: -1.60 mg/dL; 95% CI:-3.05,-0.14, p = 0.03, k = 5, n = 349), weight (WMD: -0.23 kg, 95% CI: -0.44, -0.02, p = 0.03, k = 3, n = 182), and diastolic blood pressure (WMD: -1.39 mmHg, 95% CI: -2.21, -0.56, p = 0.001, k = 3, n = 185). No effect on total cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides, body mass index, and systolic blood pressure was found. The consumption of pigmented rice may improve cardiometabolic risk factors. However, the small number of studies and differences in study design, including participants' health status, form of rice utilized, and duration of intervention, support the need for more high-quality trials to further investigate these findings.
Topics: Adult; Humans; Antioxidants; Cardiovascular Diseases; Glucose; Insulins; Oryza; Randomized Controlled Trials as Topic
PubMed: 37676476
DOI: 10.1007/s13668-023-00496-7 -
Plants (Basel, Switzerland) May 2023Bone metabolism is a complex process which is influenced by the activity of bone cells (e.g., osteocytes, osteoblasts, osteoclasts); the effect of some specific... (Review)
Review
Bone metabolism is a complex process which is influenced by the activity of bone cells (e.g., osteocytes, osteoblasts, osteoclasts); the effect of some specific biomarkers (e.g., parathyroid hormone, vitamin D, alkaline phosphatase, osteocalcin, osteopontin, osteoprotegerin, osterix, RANKL, Runx2); and the characteristic signaling pathways (e.g., RANKL/RANK, Wnt/β, Notch, BMP, SMAD). Some phytochemical compounds-such as flavonoids, tannins, polyphenols, anthocyanins, terpenoids, polysaccharides, alkaloids and others-presented a beneficial and stimulating effect in the bone regeneration process due to the pro-estrogenic activity, the antioxidant and the anti-inflammatory effect and modulation of bone signaling pathways. Lately, nanomedicine has emerged as an innovative concept for new treatments in bone-related pathologies envisaged through the incorporation of medicinal substances in nanometric systems for oral or local administration, as well as in nanostructured scaffolds with huge potential in bone tissue engineering.
PubMed: 37653972
DOI: 10.3390/plants12102055 -
Frontiers in Nutrition 2023Resveratrol is a natural polyphenol compound that is widely present in herbal medicines such as , , and Catsiatora Linn and is used in traditional Chinese medicine to...
BACKGROUND
Resveratrol is a natural polyphenol compound that is widely present in herbal medicines such as , , and Catsiatora Linn and is used in traditional Chinese medicine to treat metabolic bone deseases. Animal experiments have shown that resveratrol may have a strong treatment effect against osteoporosis (OP). The purpose of this study was to explore the efficacy of resveratrol in treating OP animal models based on preclinical research data.
METHODS
This study was completed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases from inception to May 8, 2023, to identify animal experiments on the treatment of OP with resveratrol. The effect sizes of bone mineral density (BMD), parameters of micro-CT, serum calcium, phosphorus, alkaline phosphatase (ALP) and osteocalcin were expressed as the mean differences (MDs) and 95% confidence intervals (CIs). RevMan 5.4 software was used for data analysis.
RESULTS
This meta-analysis included a total of 15 animal experiments, including 438 OP rats. The meta-analysis results showed that compared with the control group, resveratrol (<10, 10-25, 40-50, ≥ 60 mg/kg/day) significantly increased femoral and lumbar bone mineral density (BMD) in OP rats ( < 0.05). Resveratrol (<10 mg/kg/day) significantly increased the BMD of the total body (MD = 0.01, 95% CI: 0.01 to 0.01, < 0.001). In terms of improving the parameters related to micro-CT, resveratrol (40-50 mg/kg/day) can increase trabecular thickness and trabecular number and reduce trabecular spacing ( < 0.05). Compared with the control group, resveratrol can reduce the concentration of calcium and phosphorus in serum but has no significant effect on serum ALP and osteocalcin ( > 0.05). The results of subgroup analysis showed that resveratrol increased the whole-body BMD of SD rats ( = 0.002) but did not improve the whole-body BMD of 3-month-old rats ( = 0.17).
CONCLUSION
Resveratrol can increase BMD in OP rat models, and its mechanism of action may be related to improving bone microstructure and regulating calcium and phosphorus metabolism. The clinical efficacy of resveratrol in the treatment of OP deserves further research.
PubMed: 37575330
DOI: 10.3389/fnut.2023.1234756 -
Alternative Therapies in Health and... Sep 2023Turmeric is a well-known herb that has been used in many traditional medicinal systems since ancient times. Turmeric roots contain hydrophobic polyphenols called... (Meta-Analysis)
Meta-Analysis
CONTEXT
Turmeric is a well-known herb that has been used in many traditional medicinal systems since ancient times. Turmeric roots contain hydrophobic polyphenols called curcuminoids, which have proven anti-inflammatory and antioxidant effects and are shown to be beneficial for the management of musculoskeletal health. Various products containing curcumin or turmeric extract are commercially available.
OBJECTIVE
This systematic review and meta-analysis of randomized clinical trials (RCTs) is intended to evaluate the effective dose, safety, and efficacy of commercial turmeric extract and curcumin supplements in musculoskeletal health.
DESIGN
The research team performed a systematic literature search of PubMed, Google Scholar, and Cochrane Library databases and conducted a meta-analysis according to PRISMA guidelines.
SETTING
Authors from India and USA contributed to this systematic review and meta-analysis.
RESULTS
The research team analyzed 21 prospective, randomized clinical studies, of which seven studies were focused on skeletal muscle health and fourteen on joint health. Statistical heterogeneity was established based on the results of heterogeneity analysis of a Chi-square (χ2) value for Cochran's Q statistic of 29.3765 for musculoskeletal and 3666.80 for joint health studies (P < .0001 for both analyses). Therefore, the random effects model was used. The χ2 value of the random effects model was 216.5545 for skeletal muscle health studies and 1400.65 for joint health studies, which was statistically significant with P < .0001 for both analyses.
CONCLUSIONS
Turmeric extract and curcumin supplements can be effective adjuvants for the management of musculoskeletal health, with a low incidence of AEs. The water-dispersible turmeric extract, WDTE60N, at a dose of 250 mg per day, was found to be more effective than other curcumin products. However, the studies included in the analysis were conducted using diverse doses and treatment durations. Further evaluation using comparisons in future clinical trials can establish the appropriate effective dose of curcumin supplements for the overall maintenance of musculoskeletal health.
Topics: Humans; Curcumin; Curcuma; Plant Extracts; Anti-Inflammatory Agents
PubMed: 37574203
DOI: No ID Found