A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers

Effects of Anthocyanins on Cognition and Vascular Function: A Systematic Review

SCOPE

Good vascular function is crucial for cerebral blood flow and cognitive performance. Diets high in anthocyanins have been shown to improve vascular function and are associated with improvements in cognition. This systematic review investigates randomized controlled trials examining the impact of anthocyanin intake on both cognition and vascular function.

METHODS AND RESULTS

Of the 1486 studies identified through searching Ovid Medline and AMED, PsychInfo, Web of Science, and Scopus, 20 studies are selected which measured cognitive and vascular function. Overall, positive effects on verbal and working memory are observed, which are supported by studies using functional magnetic resonance imaging to demonstrate increased blood flow in brain regions related to these cognitive domains. However, effects of anthocyanins on blood pressure and markers of endothelial function are inconsistent.

CONCLUSION

This systematic review provides evidence for a positive effect of anthocyanins on cognition and insight into the relevance of endothelial function. Anthocyanins are widely available and can be easily consumed in a range of different fruits, vegetables, and other products. Further studies should establish the optimal daily intake of anthocyanins for cardiovascular and cognitive health.

Roselle (Hibiscus sabdariffa L.) extract as an adjunct to valsartan in patients with mild chronic kidney disease: A double-blind randomized controlled clinical trial

Objective

The objective of this study was to evaluate the effectiveness of Hibiscus sabdariffa L. extract (HS) as an adjunct to valsartan in the treatment of high blood pressure in patients with mild chronic kidney disease (CKD).

Materials and Methods

This trial was conducted in Gorgan, Iran. Seventy-two participants with CKD and high blood pressure were randomly assigned to either the HS group, receiving a 350 mg pill every 12 hr for 90 days along with 40 mg of valsartan every 12 hr, or the control group (40 mg valsartan + 12.5 mg hydrochlorothiazide). The primary objective was to assess the improvement of hypertension, while secondary objectives included the evaluation of proteinuria, albuminuria, kidney function, lipid profile, and electrolyte levels. Molecular docking analysis was performed to examine the mechanisms of action of the isolated components of HS.

Results

Out of 80 initial participants, 72 were included in the analysis. Both groups showed a significant reduction in blood pressure (p<0.001). The HS group demonstrated a statistically significant decrease in lipid profile (p<0.001). There were no statistically significant differences between the groups regarding the reduction of renal markers. Molecular docking analysis revealed that the compounds present in HS, particularly its anthocyanins and flavonoids, exhibited greater angiotensin-converting enzyme (ACE) inhibitory potential than hydrochlorothiazide in both domains. Moreover, the compounds met the criteria for drug likeness and Lipinski rules.

Conclusion

Adjunctive therapy with HS showed promising results in reducing hypertension and improving lipid profile in patients with CKD.

The effects of blueberry and cranberry supplementation on blood pressure in patients with cardiovascular diseases: A systematic review and meta-analysis of randomized clinical trials

Blueberries and cranberries are berry fruits with the highest number of randomized clinical trials (RCTs) focusing on blood pressure (BP). This systematic review and meta-analysis of RCTs analyzed the effects of blueberry and cranberry supplementation alone and in concert with systolic BP (SBP) and diastolic BP (DBP) in patients with cardiometabolic diseases. The searches were performed until August 2023 in the following databases: PubMed, Scopus, Web of Science, Cochrane, and Embase. Studies that examined the effects of blueberry or cranberry intake/supplementation were included. The risk of bias was evaluated using the Rob 2 scale. A meta-analysis was performed to estimate the effects of blueberry and cranberry supplementation on BP levels in patients with cardiometabolic diseases. A total of 17 articles were included, from which two found significant results from blueberry and/or cranberry supplementation in reducing BP. Pooled results revealed statistically non-significant reductions of -0.81 mm Hg for SBP (95% confidence interval [CI]: -2.26, 0.63; I2  = 0%) and -0.15 mm Hg for DBP (95% CI: -1.36, 1.05; I2  = 27%). Blueberry and/or cranberry supplementation had neutral effects on SBP and DBP in patients with cardiometabolic diseases, regardless of duration or age. Further high-quality studies are needed to firmly establish clinical efficacy.

Antioxidant, enzymes inhibitory, physicochemical and sensory properties of instant bio-yoghurts containing multi-purpose natural additives

This study aimed to assess the antioxidant, enzyme inhibitory, physicochemical and sensory properties of instant bio-yoghurts containing multi-purpose natural additives. Multi-purpose natural additives were formulated with three natural additives (sweet detar seed, ginger rhizome, and hibiscus calyx flours, as a thickener, flavourant and colourant, respectively) blends at proportions derived from the Design Expert. The additives' synthetic counterparts were formulated with sodium carboxymethylcellulose, vanilla flavor, and red colourant at the same proportions. After that, yoghurt was produced and the additives blends were incorporated into it either in aqueous extract or flour form, yielding bio-yoghurts designated multi-purpose natural additive extract-containing yoghurt (MNAE-yoghurt), multi-purpose natural additive flour-added yoghurt (MNAF-yoghurt), and their multi-purpose synthetic additives-containing counterparts (MSAE-yoghurt and MSAF-yoghurt). A commercially-available bio-yoghurt served as a control. All the yoghurts were lyophilized to obtain instant bio-yoghurts. Subsequently, bioactive components (total phenolics, tannins, total flavonoids and saponins), antioxidants and enzymes [alpha-amylase, alpha-glucosidase, pancreatic lipase, and angiotensin 1-converting enzyme (ACE)] inhibitory activities, as well as proximate, physicochemical and sensory qualities of the bio-yoghurts were determined. The MNAE-yoghurt and MNAF-yoghurt had higher bioactive constituents, total titratable acid levels, and more potent antioxidant and enzyme inhibitory properties, but a lower pH than their synthetic counterparts and the control. The total phenolics, tannins, total flavonoids and saponins levels of MNAE-yoghurt and MNAF-yoghurt were 14.40 ± 0.24 and 16.54 ± 0.62 mg/g, 1.65 ± 0.04 and 1.74 ± 0.08 mg/g, 4.25 ± 0.03 and 4.40 ± 0.02 mg/g, 0.64 ± 0.01 and 0.66 ± 0.02 mg/g, respectively. Among the natural multi-purpose additives-containing bio-yoghurts, MNAF-yoghurt had higher bioactive constituents and stronger antioxidant and enzymes inhibitory properties. Its α-amylase, α-glucosidase, ACE, and pancreatic lipase IC50 values were 72.47 ± 0.47, 74.07 ± 0.02, 25.58 ± 2.58, and 33.56 ± 29.66 μg/mL, respectively. In contrast, MNAE-yoghurt had the highest protein (13.70 ± 0.85%) and the lowest fat (2.63 ± 0.71%) contents. The sensory attributes of all the bio-yoghurts fell within an acceptable likeness range. Overall, the inclusion of multi-purpose natural additives blends enhanced the instant bio-yoghurts' nutritional, health-promoting, and sensory qualities.

The Potential of Natural Products in the Management of Cardiovascular Disease

Cardiovascular Disease (CVD) is one of the most prevalent diseases in the world, comprising a variety of disorders such as hypertension, heart attacks, Peripheral Vascular Disease (PVD), dyslipidemias, strokes, coronary heart disease, and cardiomyopathies. The World Health Organization (WHO) predicts that 22.2 million people will die from CVD in 2030. Conventional treatments for CVDs are often quite expensive and also have several side effects. This potentiates the use of medicinal plants, which are still a viable alternative therapy for a number of diseases, including CVD. Natural products' cardio-protective effects result from their anti-oxidative, anti-hypercholesterolemia, anti-ischemic, and platelet aggregation-inhibiting properties. The conventional therapies used to treat CVD have the potential to be explored in light of the recent increase in the popularity of natural goods and alternative medicine. Some natural products with potential in the management of cardiovascular diseases such as Allium sativum L., Ginkgo biloba, Cinchona ledgeriana, Ginseng, Commiphora mukul, Digitalis lanata, Digitalis purpurea L., Murrayakoenigii, Glycyrrhiza glabra, Polygonum cuspidatum, Fenugreek, Capsicum annuum, etc. are discussed in this article.

Prevalence and Factors Associated with Metabolic Syndrome among Non-Diabetic Saudi Adults: A Cross-Sectional Study

(1) Introduction: given the high prevalence of metabolic syndrome (MetS) in Saudi Arabia, especially in Jeddah, this study aims to understand the dietary and lifestyle-related risk factors among Jeddah's non-diabetic adults. (2) Material and Methods: Employing a cross-sectional design, non-diabetic adults were sourced from public healthcare centers. Demographics, lifestyle, and dietary habits were surveyed. Blood pressure, anthropometrics, and fasting blood samples measuring plasma glucose, serum triglycerides, and HDL cholesterol were collected. The age cut-off for MetS was ascertained using the receiver operating characteristic curve. Variables influencing MetS were evaluated using univariate logistic regression, and consequential factors underwent multivariate analysis, adjusted for age and sex. (3) Results: Among 1339 participants, 16% had MetS, with age being the strongest predictor (p < 0.001). The optimal age cut-off was 32 years. For those <32, elevated BP in men and waist circumference (WC) in women were most prevalent. For those >32, elevated WC was dominant in both sexes. Univariate logistic regression revealed that higher income and education correlated with lower MetS prevalence, while marriage and smoking were risk factors. Adjusting for age and sex, only very high income had a significant low-risk association (p = 0.034). (4) Conclusion: MetS is notable in the studied group, with age as the pivotal predictor. High income reduces MetS risk, while marital status and smoking could increase it. Since this was a cross-sectional study, cohort studies are needed to validate our findings.

Effect of dietary supplementation with Diuripres® on blood pressure, vascular health, and metabolic parameters in individuals with high-normal blood pressure or stage I hypertension: The CONDOR randomized clinical study

Our aim was to evaluate if a nutritional intervention with a dietary supplement (Diuripres®) containing magnesium, standardized extract of orthosiphon, hawthorn, and hibiscus could positively affect blood pressure (BP), vascular health, and metabolic parameters in 60 individuals with high-normal BP or stage I hypertension. Participants followed a low-fat low-sodium Mediterranean diet for 4 weeks before being randomly allocated to 8-week treatment with two pills each day of either Diuripres® or placebo. Diuripres® significantly decreased systolic BP compared to placebo after 4 weeks (3.1 ± 0.8 mmHg; p < 0.05) and more consistently after 8 weeks (3.4 ± 0.9 mmHg; p < 0.05). At 8-week follow-up, after correction for multiple testing, dietary supplementation with Diuripres® was associated with significant improvements in diastolic BP (-3.1 ± 0.6 mmHg; p < 0.05), aortic BP (-4.3 ± 0.4 mmHg; p < 0.05), and high-sensitivity C-reactive protein (hs-CRP; 0.04 ± 0.01 mg/dL; p < 0.05) in comparison with baseline. The reductions in diastolic BP (--3.8 ± 0.7 mmHg; p < 0.05), aortic BP (-5.2 ± 1.0 mmHg; p < 0.05), and hs-CRP (-0.03 ± 0.01 mg/dL; p < 0.05) were also significant compared to placebo. Therefore, our study shows that dietary supplementation with Diuripres® may be useful in individuals with high-normal BP or stage I hypertension.

Dietary modification for prevention and control of high blood pressure

Hypertension (HT) remains the leading cause of cardiovascular and premature death around the world. Diet is one of the important factors that contributes to the development of HT. We review the current evidence of how different dietary factors may influence blood pressure (BP) and consequent development of HT. There is evidence that BP is positively associated with higher consumption of sodium, alcohol, animal-based protein such as red meat, low-quality carbohydrates such as sugar-sweetened beverages, and saturated fatty acids. On the contrary, other dietary constituents have BP-lowering effects. These include potassium, calcium, magnesium, yogurt, eggs, plant-based proteins such as soy and legumes, mono- and polyunsaturated fatty acids, and high-quality carbohydrates such as whole grain and fruits. Dietary fibre is unrelated to BP lowering, possibly due to the different mechanisms of various types of fibre. The effects of caffeine, hibiscus tea, pomegranate, and sesame on BP are also unclear as evidence is hard to assess due to the varying concentrations and different types of drinks used in studies. Implementing dietary changes such as the Dietary Approaches to Stop Hypertension (DASH diet) or adopting a Mediterranean diet has been shown to reduce and control BP. Although the effect of diet on BP control has been established, the optimal amount of each dietary component and consequent ability to devise a personalized diet for HT prevention and BP control for different populations still require further investigation.

Physicochemical and Functional Properties and Storage Stability of Chitosan-Starch Films Containing Micellar Nano/Microstructures with Turmeric and Hibiscus Extracts

The dynamic development of the food industry and the growing interest of consumers in innovative solutions that increase the comfort and quality of life push the industry towards seeking pioneering solutions in the field of food packaging. Intelligent and active packaging, which affects the quality and durability of food products and allows one to determine their freshness, is still a modern concept. The aim of our study was to obtain two types of films based on chitosan and starch with micellar nanostructures containing extracts from turmeric rhizomes and hibiscus flowers. The presence of spherical nanostructures was confirmed using a scanning electron microscope. The structural and optical properties of the obtained composites were characterised by Fourier-transform infrared (FTIR), UltraViolet-Visible (UV-VIS), and photoluminescence (PL) spectroscopy. Scanning electron microscopy (SEM) analysis confirmed the presence of spherical micellar structures with a size of about 800 nm in the obtained biocomposites. The presence of nano-/microstructures containing extracts affected the mechanical properties of the composites: it weakened the strength of the films and improved their elongation at break (EAB). Films with nano-/microparticles were characterised by a higher water content compared to the control sample and lower solubility, and they showed stronger hydrophilic properties. Preliminary storage tests showed that the obtained biocomposites are sensitive to changes occurring during the storage of products such as cheese or fish. In addition, it was found that the film with the addition of turmeric extract inhibited the growth of microorganisms during storage. The results suggest that the obtained bionanocomposites can be used as active and/or intelligent materials.

Effect of the Combination of Hibiscus sabdariffa in Combination with Other Plant Extracts in the Prevention of Metabolic Syndrome: A Systematic Review and Meta-Analysis

Metabolic syndrome is a complex and multifactorial disorder associated with increased risk of cardiovascular disease and type 2 diabetes, exacerbated by a sedentary lifestyle and situations such as the COVID-19 pandemic. Recent studies have shown that consumption of fruits and vegetables high in polyphenols has a protective effect, reducing cardiovascular risk. Hibiscus sabdariffa (HS) in combination with other plant extracts has recently attracted scientists' attention due to its potential use in the treatment of metabolic syndrome. This systematic review and meta-analysis examines the effects of HS in combination with other plant extracts on the prevention of metabolic syndrome, exploring their synergistic effects and potential as therapeutic agents. For this purpose, a systematic search of randomized clinical trials (RCTs) was conducted in four different databases and the data obtained were then used for a meta-analysis. Initially, the titles and abstracts of 1368 studies were read. From these, 16 studies were examined closely for their eligibility, and finally, seven RCTs with 332 participants were included in both the meta-analysis and the qualitative analysis. Our results show that HS in combination with other plant extracts improved anthropometric parameters, blood pressure, and lipid profile (low density lipoprotein cholesterol and total cholesterol) compared to a placebo control group. It is important to note that although this meta-analysis suggests that HS in combination with other plant extracts may have a beneficial effect on cardiovascular parameters, further research is needed to determine the optimal dose and intake duration.

Therapeutic Potential of Hibiscus sabdariffa Linn. in Attenuating Cardiovascular Risk Factors

Cardiovascular diseases (CVDs) represent a broad spectrum of diseases afflicting the heart and blood vessels and remain a major cause of death and disability worldwide. CVD progression is strongly associated with risk factors, including hypertension, hyperglycemia, dyslipidemia, oxidative stress, inflammation, fibrosis, and apoptosis. These risk factors lead to oxidative damage that results in various cardiovascular complications including endothelial dysfunctions, alterations in vascular integrity, the formation of atherosclerosis, as well as incorrigible cardiac remodeling. The use of conventional pharmacological therapy is one of the current preventive measures to control the development of CVDs. However, as undesirable side effects from drug use have become a recent issue, alternative treatment from natural products is being sought in medicinal plants and is gaining interest. Roselle (Hibiscus sabdariffa Linn.) has been reported to contain various bioactive compounds that exert anti-hyperlipidemia, anti-hyperglycemia, anti-hypertension, antioxidative, anti-inflammation, and anti-fibrosis effects. These properties of roselle, especially from its calyx, have relevance to its therapeutic and cardiovascular protection effects in humans. This review summarizes the findings of recent preclinical and clinical studies on roselle as a prophylactic and therapeutic agent in attenuating cardiovascular risk factors and associated mechanisms.

Anthocyanins and Vascular Health: A Matter of Metabolites

Anthocyanins are a subgroup of flavonoid polyphenols previously investigated for improving cardiovascular health and preventing the development of endothelial dysfunction. However, their poor bioavailability raises the question of whether the observed biological activity is due to their metabolites. Phenolic metabolites can reach higher plasma concentrations and can persist in the circulation for periods much longer than their original anthocyanin form; therefore, the biological activity and health promoting effects of anthocyanins may differ from their metabolites. To address this, recent studies have facilitated different cell models, in vivo studies and explored physiologically relevant concentrations to better understand their mechanisms of action. The criteria were chosen based on previous reports demonstrating that anthocyanins can improve endothelial function via modulation of the Akt-endothelial nitric oxide synthase pathway and transcription factors Nrf2 and NF-κB, which made it critical to assess the phenolic metabolites' modes of action via these pathways. This review demonstrates how phenolic metabolites differ in bioactivity from their precursor anthocyanin, demonstrating improved endothelial function in response to inflammatory mediators at concentrations that are tolerated in vivo. The review highlights the crucial need for further studies to focus on improving the bioavailability of metabolites in isolation and explore the effect of metabolites in mixtures.

Gynostemma pentaphyllum for dyslipidemia: A systematic review of randomized controlled trials

Objective: To evaluate the lipid-lowering effect and safety of Gynostemma pentaphyllum (GP) used alone or as adjunctive therapy for dyslipidemia. Methods: Eight databases and three clinical trial registries were searched until January 2022. Randomized controlled trials (RCTs) assessing the effectiveness of GP for dyslipidemia were included. Trial quality was assessed using the Cochrane Risk of Bias Tool 2.0. Data were analyzed by RevMan 5.4 with effects estimated as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI). Results: Twenty-two RCTs involving 2,407 dyslipidemia participants were included. Regarding the risk of bias, 14 RCTs had some concerns, seven RCTs were high, and one trial was low. GP was comparable to n-3 fatty acids (RR 0.89, 95% CI 0.62-1.28) and red yeast rice (RR 0.33, 95% CI 0.1-1.12) on normalization of serum lipids. GP plus n-3 fatty acid was superior in normalization of triglycerides (TG) and total cholesterol (TC) than n-3 fatty acids (RR 1.34, 95% CI 1.01-1.77). GP was similar to lipid-lowering agents (statins, fibrates, and n-3 fatty acids) in regulating TG, TC, and high-density lipoprotein cholesterol (HDL-C). GP plus lipid-lowering agents were superior to lipid-lowering agents in TG (MD -0.65 mmol/L, 95% CI -1.03 to -0.28), LDL-C (MD -0.57 mmol/L, 95% CI -1.07 to -0.08), and HDL-C (MD 0.15 mmol/L, 95% CI 0.11-0.20). GP was inferior to red yeast rice in TC (MD 0.64 mmol/L, 95% CI 0.15-1.13), TG (MD 0.43 mmol/L, 95% CI 0.15-0.71), and HDL-C (MD -0.25 mmol/L, 95% CI -0.47 to -0.04). GP had fewer adverse events than lipid-lowering drugs. Conclusion: Very low certainty evidence showed that GP's effects on TC, TG, and HDL-C were comparable to that of lipid-lowering agents. Low certainty evidence showed that red yeast rice was superior to GP in TC, TG, and HDL-C. Low to moderate certainty evidence showed that the effects of GP plus lipid-lowering agents were superior to that of lipid-lowering agents on TG, LDL-C, and HDL-C. GP use for more than 8 weeks appears safe. Systematic Review Registration: https://inplasy.com/, identifier INPLASY202210135.