The barberry juice effects on metabolic factors and oxidative stress in patients with type 2 diabetes: A randomized clinical trial

Efficacy of Berberis vulgaris and Berberis integerrima on glycemic indices and weight profile in type 2 diabetic patients: A systematic review and meta-analysis of randomized controlled trials

Type 2 diabetes mellitus (T2DM) is a multifactorial lifelong condition. Berberis vulgaris (BV) and Berberis integerrima (BI) regulate glucose levels with minimal adverse effects. In this systematic review and meta-analysis, we evaluate the effect of BV and BI on glycemic indices, weight, and body mass index (BMI) against placebo. Four electronic databases were searched till September 24, 2023. Inclusion criteria for studies were: (a) T2DM patients; (b) berberis (vulgaris/integerrima) therapy as intervention; (c) control group of placebo or metformin; (d) outcomes including fasting blood glucose (FBG) levels, glycated hemoglobin (HbA1c%), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), fasting serum insulin (FSI), 2-h postprandial glucose (2hPPG), fructosamine, weight, and BMI; (e) randomized controlled trials (RCTs). Data was pooled using a random-effects analysis model on Review Manager. The inverse variance statistical method was applied keeping weighted mean difference (WMD) as the effect measure. The Cochrane risk of bias tool evaluated the risk of bias. A p-value of less than 0.05 was considered significant. Nine RCTs comprising 547 patients were included. Significant reduction was noted with berberis therapy in FBG (WMD: -14.52; 95% CI = -22.97, -6.07; P = 0.0008); HbA1c % (WMD: -0.30; 95% CI = -0.53, -0.07; P = 0.01); HOMA-IR (WMD: -0.97; 95% CI = -1.56, 0.37; P = 0.001). No significant differences were noted between the two groups in 2hPPG (WMD: 6.52; 95% CI = -21.57, 34.61; P = 0.65); FSI (WMD: -0.79; 95% CI = -1.80, 0.22, P = 0.13); Fructosamine (WMD: -12.57; 95% CI = -40.74, 15.60; P = 0.38); Weight (WMD: -1.89; 95% CI = -4.55, 0.76; P = 0.16) and BMI (WMD: -0.12; 95% CI = -0.90, 0.65; P = 0.76). The data showed significant reduction in FBG and improved insulin levels but limited effects were observed in other glycemic indexes. More extensive RCTs are required globally to achieve a holistic comprehension of the connection between berberis and T2DM.

Herbal Products as Complementary or Alternative Medicine for the Management of Hyperglycemia and Dyslipidemia in Patients with Type 2 Diabetes: Current Evidence Based on Findings of Interventional Studies

Type 2 diabetes (T2D) is known as a major public health problem with a noticeable adverse impact on quality of life and health expenditures worldwide. Despite using routine multiple pharmacological and nonpharmacological interventions, including diet therapy and increasing physical activity, controlling this chronic disease remains a challenging issue, and therapeutic goals are often not achieved. Therefore, recently, other therapeutic procedures, such as using herbal products and functional foods as complementary or alternative medicine (CAM), have received great attention as a new approach to managing T2D complications, according to the literature. We reviewed the existing evidence that supports using various fundamental medicinal herbs, including cinnamon, saffron, ginger, jujube, turmeric, and barberry, as CAM adjunctive therapeutic strategies for T2D patients. The current review addressed different aspects of the potential impact of the abovementioned herbal products in improving glycemic indices and lipid profiles, including the effect size reported in the studies, their effective dose, possible side effects, herbs-drug interactions, and their potential action mechanisms.

Health effects of 100% fruit and vegetable juices: evidence from human subject intervention studies

The health effects of 100% fruit and vegetable juices (FVJ) represent a controversial topic. FVJ contain notable amounts of free sugars, but also vitamins, minerals, and secondary compounds with proven biological activities like (poly)phenols and carotenoids. The review aimed to shed light on the potential impact of 100% FVJ on human subject health, comprehensively assessing the role each type of juice may have in specific health outcomes for a particular target population, as reported in dietary interventions. The effects of a wide range of FVJ (orange, grapefruit, mandarin, lemon, apple, white, red, and Concord grapes, pomegranate, cranberry, chokeberry, blueberry, other minor berries, sweet and tart cherry, plum, tomato, carrot, beetroot, and watermelon, among others) were evaluated on a series of outcomes (anthropometric parameters, body composition, blood pressure and vascular function, lipid profile, glucose homeostasis, biomarkers of inflammation and oxidative stress, cognitive function, exercise performance, gut microbiota composition and bacterial infections), providing a thorough picture of the contribution of each FVJ to a health outcome. Some juices demonstrated their ability to exert potential preventive effects on some outcomes while others on other health outcomes, emphasising how the differential composition in bioactive compounds defines juice effects. Research gaps and future prospects were discussed. Although 100% FVJ appear to have beneficial effects on some cardiometabolic health outcomes, cognition and exercise performance, or neutral effects on anthropometric parameters and body composition, further efforts are needed to better understand the impact of 100% FVJ on human subject health.

Modulation of the antioxidant enzyme paraoxonase-1 for protection against cardiovascular diseases

AIM

The enzyme paraoxonase 1 (PON1) bound to high-density lipoprotein has received special attention for its protective role against stress-mediated damage and use as a potential regulatory target in atherosclerosis and related vascular diseases.

DATA SYNTHESIS

We present an overview of the literature on PON1 activity and mRNA levels by investigating its modulation for clinical translations. Specifically, the expression of PON1 and its regulated activity can be modified in different ways with natural substances, drugs, and lifestyle factors thar affect the development of atherosclerosis.

CONCLUSIONS

The endothelial contribution of PON1 to overcome differences considering an individual's disease development risk is supported by polymorphism interaction data and the susceptibility to modify PON1 responses in chronic events composed by biological and environmental factors.

Anti-inflammatory, antioxidant, and immunomodulatory effects of Berberis vulgaris and its constituent berberine, experimental and clinical, a review

Berberis vulgaris (B. vulgaris or barberry) is a medicinal plant that has been used for various purposes in traditional medicine. Berberine is one of the main alkaloids isolated from B. vulgaris and other plants. Both B. vulgaris and berberine have shown anti-inflammatory, antioxidant, and immunomodulatory effects in different experimental models and clinical trials. This review aims to summarize the current evidence on the mechanisms and applications of B. vulgaris and berberine in modulating inflammation, oxidative stress, and immune responses. The literature search was performed using PubMed, Scopus, and Google Scholar databases until August 2023. The results indicated that B. vulgaris and berberine could inhibit the production of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), interleukin 6 (IL-6), and interleukin-17 (IL-17), and enhance the expression of anti-inflammatory cytokines, such as interleukin 10 (IL-10) and transforming growth factor-β (TGF-β), in various cell types and tissues. B. vulgaris and berberine can also scavenge free radicals, increase antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), and reduce lipid peroxidation and DNA damage. B. vulgaris and berberine have been reported to exert beneficial effects in several inflammatory, oxidative, and immune-related diseases, such as diabetes, obesity, cardiovascular diseases, neurodegenerative diseases, autoimmune diseases, allergic diseases, and infections. However, more studies are needed to elucidate the optimal doses, safety profiles, and potential interactions of B. vulgaris and berberine with other drugs or natural compounds.

Fruits of Wild-Grown Shrubs for Health Nutrition

Cultivated fruits and berries, such as raspberries, strawberries, black currants, cherries, blueberries, are generally recognized sources of antioxidants, vitamins, minerals, and other substances beneficial to human health and well-being. However, there are also wild berries and fruits that are of undoubted interest as food products having valuable medicinal properties due to the presence of phenolic compounds, antioxidants, and vitamins. These fruits have a great potential to be used in functional food making. The present review is dedicated to fruits of wild-grown shrubs Bird cherry (Prunus padus L.), Rowan berry (Sorbus aucuparia L.), Guelder rose (Viburnum opulus L.), Black elderberry (Sambucus nigra L.), and Barberry (Berberis vulgaris L.) The chemical compositions of these wild berries are described as well as their effects on the improvement of human health proved by clinical trials and epidemiological studies. The possibilities of using the fruits of wild-grown shrubs in the preparation of functional foods and examples of their implementation for the manufacturing of dairy, bakery and meat products are considered.

Consumption of 100% Fruit Juice and Body Weight in Children and Adults: A Systematic Review and Meta-Analysis

Importance

Concerns have been raised that frequent consumption of 100% fruit juice may promote weight gain. Current evidence on fruit juice and weight gain has yielded mixed findings from both observational studies and clinical trials.

Objective

To synthesize the available evidence on 100% fruit juice consumption and body weight in children and adults.

Data Sources

MEDLINE, Embase, and Cochrane databases were searched through May 18, 2023.

Study Selection

Prospective cohort studies of at least 6 months and randomized clinical trials (RCTs) of at least 2 weeks assessing the association of 100% fruit juice with body weight change in children and adults were included. In the trials, fruit juices were compared with noncaloric controls.

Data Extraction and Synthesis

Data were pooled using random-effects models and presented as β coefficients with 95% CIs for cohort studies and mean differences (MDs) with 95% CIs for RCTs.

Main Outcomes and Measures

Change in body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) was assessed in children and change in body weight in adults.

Results

A total of 42 eligible studies were included in this analysis, including 17 among children (17 cohorts; 0 RCTs; 45 851 children; median [IQR] age, 8 [1-15] years) and 25 among adults (6 cohorts; 19 RCTs; 268 095 adults; median [IQR] age among cohort studies, 48 [41-61] years; median [IQR] age among RCTs, 42 [25-59]). Among cohort studies in children, each additional serving per day of 100% fruit juice was associated with a 0.03 (95% CI, 0.01-0.05) higher BMI change. Among cohort studies in adults, studies that did not adjust for energy showed greater body weight gain (0.21 kg; 95% CI, 0.15-0.27 kg) than studies that did adjust for energy intake (-0.08 kg; 95% CI, -0.11 to -0.05 kg; P for meta-regression <.001). RCTs in adults found no significant association of assignment to 100% fruit juice with body weight but the CI was wide (MD, -0.53 kg; 95% CI, -1.55 to 0.48 kg).

Conclusion and Relevance

Based on the available evidence from prospective cohort studies, in this systematic review and meta-analysis, 1 serving per day of 100% fruit juice was associated with BMI gain among children. Findings in adults found a significant association among studies unadjusted for total energy, suggesting potential mediation by calories. Further trials of 100% fruit juice and body weight are desirable. Our findings support guidance to limit consumption of fruit juice to prevent intake of excess calories and weight gain.

Acetone extracts of Berberis vulgaris and Cornus mas L. induce apoptosis in MCF-7 breast cancer cells

Background/aim

This study aimed to determine the proliferation and apoptotic effects of extracts from Cornus mas L. and Berberis vulgaris fruits on human breast cancer cells (MCF-7).

Materials and methods

The Cornus mas L. and Berberis vulgaris fruits, which constitute the herbal material of the study, were turned into 80% acetone extract after washing. The total phenolic content in Berberis vulgaris fruit extracts was determined calorimetrically using Folin-Ciocalteu reagent. The spectrophotometric method was used to determine the total flavonoid amount of the extracts. In order to measure the antioxidant capacity of Cornus mas L. and Berberis vulgaris fruits and extracts, DPPH Radical Scavenging Power test and Cu (II) ion reducing antioxidant capacity method were applied. Cell viability rates were determined by the XTT method. Flow cytometric measurement was performed to examine the apoptotic role of the extracts in the cell by using the Annexin-V/7-AAD commercial kit.

Results

According to the data, Berberis vulgaris fruit extract appeared more effective on MCF-7 breast cancer cells in both 24 and 48 hours of exposure. Analyses made to examine the phenolic component and antioxidant capacity properties of the fruits used in the study and the results we encountered when we exposed the cell were found to be compatible with each other. Annexin-V/7-AAD method showed that the apoptotic effects of the extracts in 48 hour exposures were more effective.

Conclusion

It has been determined that Cornus mas L. and Berberis vulgaris fruits, which are rich in phenolic components with high flavonoid content and high antioxidant capacities, support the apoptosis of cancer cells.

Fructose-containing food sources and blood pressure: A systematic review and meta-analysis of controlled feeding trials

Whether food source or energy mediates the effect of fructose-containing sugars on blood pressure (BP) is unclear. We conducted a systematic review and meta-analysis of the effect of different food sources of fructose-containing sugars at different levels of energy control on BP. We searched MEDLINE, Embase and the Cochrane Library through June 2021 for controlled trials ≥7-days. We prespecified 4 trial designs: substitution (energy matched substitution of sugars); addition (excess energy from sugars added); subtraction (excess energy from sugars subtracted); and ad libitum (energy from sugars freely replaced). Outcomes were systolic and diastolic BP. Independent reviewers extracted data. GRADE assessed the certainty of evidence. We included 93 reports (147 trial comparisons, N = 5,213) assessing 12 different food sources across 4 energy control levels in adults with and without hypertension or at risk for hypertension. Total fructose-containing sugars had no effect in substitution, subtraction, or ad libitum trials but decreased systolic and diastolic BP in addition trials (P<0.05). There was evidence of interaction/influence by food source: fruit and 100% fruit juice decreased and mixed sources (with sugar-sweetened beverages [SSBs]) increased BP in addition trials and the removal of SSBs (linear dose response gradient) and mixed sources (with SSBs) decreased BP in subtraction trials. The certainty of evidence was generally moderate. Food source and energy control appear to mediate the effect of fructose-containing sugars on BP. The evidence provides a good indication that fruit and 100% fruit juice at low doses (up to or less than the public health threshold of ~10% E) lead to small, but important reductions in BP, while the addition of excess energy of mixed sources (with SSBs) at high doses (up to 23%) leads to moderate increases and their removal or the removal of SSBs alone (up to ~20% E) leads to small, but important decreases in BP in adults with and without hypertension or at risk for hypertension. Trial registration: Clinicaltrials.gov: NCT02716870.

Effect of fruit on glucose control in diabetes mellitus: a meta-analysis of nineteen randomized controlled trials

Objective

Diabetes mellitus is a worldwide health problem, and it remains unclarified whether fruit is beneficial in glycemic control. This study aimed to analyze evidence from randomized controlled trials evaluating the effect of fruit consumption on glucose control.

Methods

We searched the PubMed, EMBASE, Ovid, Web of Science, and Cochrane Central Register of Controlled Trials databases from the respective database inception dates to December 30, 2022, to identify randomized controlled trials that evaluated the effects of fruit consumption on glucose control. Two researchers independently screened the studies in accordance with the inclusion and exclusion criteria, and performed the literature quality evaluation and data extraction. RevMan 5.4 software was used to perform the data analysis.

Results

Nineteen randomized controlled trials with 888 participants were included. Fruit consumption significantly decreased the fasting blood glucose concentration (MD -8.38, 95% CI -12.34 to -4.43), but it showed no significant difference in the glycosylated hemoglobin (MD -0.17, 95% CI -0.51 to 0.17). Subgroup analyses further suggested that the consumption of both fresh and dried fruit decreased the fasting blood glucose concentration.

Conclusions

Increasing the fruit intake reduced fasting blood glucose concentration. Therefore, we recommend that patients with diabetes eat more fruits while ensuring that their total energy intake remains unchanged.

The effects of Berberis vulgaris L. and Berberis aristata L. in metabolic syndrome patients: a systematic and meta-analysis study

INTRODUCTION

This meta-analysis study assessed the effects of Berberis vulgaris L. and Berberis aristata L. in patients with metabolic syndrome.

METHODS

Data were analysed through "random-effects meta-regression" performance.

RESULTS

The findings indicated that LDL was 0.68 and 2.92 lower in the B. vulgaris L. and B. aristata L.-treated groups versus the controls. The HDL was 0.71-fold higher in the B. aristata L.-treated group versus the controls. The total-cholesterol levels were 1.02 and 2.25 folds lower in the B. vulgaris L. and B. aristata L.-treated groups versus the matched control groups. The triglyceride levels were 1.35 and 1.16-fold lower in the B. vulgaris L. and B. aristata L.-treated groups versus the controls. Glucose was 0.96 and 0.54 folds lower in the B. vulgaris L. and B. aristata L.-treated groups versus the control groups, respectively.

CONCLUSION

B. vulgaris L. and B. aristata L. have beneficial effects in patients with metabolic syndrome.

Important food sources of fructose-containing sugars and adiposity: A systematic review and meta-analysis of controlled feeding trials

BACKGROUND

Sugar-sweetened beverages (SSBs) providing excess energy increase adiposity. The effect of other food sources of sugars at different energy control levels is unclear.

OBJECTIVES

To determine the effect of food sources of fructose-containing sugars by energy control on adiposity.

METHODS

In this systematic review and meta-analysis, MEDLINE, Embase, and Cochrane Library were searched through April 2022 for controlled trials ≥2 wk. We prespecified 4 trial designs by energy control: substitution (energy-matched replacement of sugars), addition (energy from sugars added), subtraction (energy from sugars subtracted), and ad libitum (energy from sugars freely replaced). Independent authors extracted data. The primary outcome was body weight. Secondary outcomes included other adiposity measures. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the certainty of evidence.

RESULTS

We included 169 trials (255 trial comparisons, n = 10,357) assessing 14 food sources at 4 energy control levels over a median 12 wk. Total fructose-containing sugars increased body weight (MD: 0.28 kg; 95% CI: 0.06, 0.50 kg; P_MD = 0.011) in addition trials and decreased body weight (MD: -0.96 kg; 95% CI: -1.78, -0.14 kg; P_MD = 0.022) in subtraction trials with no effect in substitution or ad libitum trials. There was interaction/influence by food sources on body weight: substitution trials [fruits decreased; added nutritive sweeteners and mixed sources (with SSBs) increased]; addition trials [dried fruits, honey, fruits (≤10%E), and 100% fruit juice (≤10%E) decreased; SSBs, fruit drink, and mixed sources (with SSBs) increased]; subtraction trials [removal of mixed sources (with SSBs) decreased]; and ad libitum trials [mixed sources (with/without SSBs) increased]. GRADE scores were generally moderate. Results were similar across secondary outcomes.

CONCLUSIONS

Energy control and food sources mediate the effect of fructose-containing sugars on adiposity. The evidence provides a good indication that excess energy from sugars (particularly SSBs at high doses ≥20%E or 100 g/d) increase adiposity, whereas their removal decrease adiposity. Most other food sources had no effect, with some showing decreases (particularly fruits at lower doses ≤10%E or 50 g/d). This trial was registered at clinicaltrials.gov as NCT02558920 (https://clinicaltrials.gov/ct2/show/NCT02558920).

The effects of berberine supplementation on cardiovascular risk factors in adults: A systematic review and dose-response meta-analysis

Cardiovascular disease (CVD) is a major concern today. Herbal medicine is one helping way to control CVD risks. One conclusive of herbal medicine is Berberine (BBR) and converse about it still exists, to clarify this issue, this meta-analysis was performed. PubMed/Medline, Scopus, and Web of Science were searched for RCTs in adults on the effect of BBR supplementation on CVD risk factors up to July 2022. The pooled results showed BBR significantly reduced triglyceride (WMD = -23.70 mg/dl; 95%CI -30.16, -17.25; P < 0.001), total cholesterol (WMD = -20.64 mg/dl; 95%CI -23.65, -17.63; P < 0.001), low-density lipoprotein WMD = -9.63 mg/dl; 95%CI, -13.87, -5.39; P < 0.001), fasting blood glucose (FBG) (WMD = -7.74 mg/dl; 95%CI -10.79, -4.70; P < 0.001), insulin (WMD = -3.27 mg/dl; 95%CI -4.46,-2.07; P < 0.001), HbA1c (WMD = -0.45%; 95%CI -0.68, -0.23; P < 0.001), HOMA-IR (WMD = -1.04; 95%CI -1.55, -0.52; P < 0.001), systolic blood pressure (WMD = -5.46 mmHg; 95%CI -8.17, -2.76; P < 0.001), weight (WMD = -0.84; 95%CI -1.34,-0.34; P < 0.001), body mass index (WMD = -0.25 kg/m2; 95%CI -0.46, -0.04; P = 0.020), while increased high-density lipoprotein (HDL) (WMD = 1.37 mg/dl; 95%CI 0.41,2.23; P = 0.005). The optimal dose of BBR was 1 g/day for TG, TC, and weight, 1.8 g/day for insulin and HOMA-IR, and 5 g/day for HDL. FBG's most efficient time frame was 40 weeks from the beginning of supplementation, whereas DBP and waist circumference was 50 weeks. In conclusion, the lipid profile, FBG balance, obesity parameters, and SBP were improved with BBR supplementation.

Systematic review registration

CRD42022347004.

The Effect of Herbal Supplements on Blood Pressure: Systematic Review and Meta-Analysis

Herbal supplements rich in phenolic compounds are evidenced to have a protective effect against cardiovascular diseases. Therefore, they are suggested to be included in diets for people with hypertension (HT). HT is a global health problem and is estimated to affect billions of people until the end of 2025. For this reason, every possible and effective solution preventing HT should be considered. The aim was to perform an updated meta-analysis and review of recently published studies to evaluate the effect of selected herbal supplements on blood pressure reduction. We searched the PubMed database with specified selection criteria, analysing the RCT studies from 2011 to 2021. A total of 31 studies were included in the analysis, and the meta-analysis was conducted on the data from 16 of them. The general effect size of all the supplements via placebo was d = 1.45, p < 0.05 for systolic blood pressure (SBP) and d = 0.31, p < 0.05 for diastolic blood pressure (DBP). The meta-analysis and review of the literature demonstrated that herbal supplements, such as resveratrol, cherry juice, beetroot juice, bergamot extracts, barberry, and pycnogenol, can be effective in blood pressure reduction and cardiovascular prevention, but attention should be paid to their appropriate dosage due to the possibility of side effects from the digestive system.

Phytochemicals as Modulators of Paraoxonase-1 in Health and Diseases

Chronic diseases such as cardiovascular disease (CVD), atherosclerosis, chronic liver disease, and neurodegenerative diseases are major causes of mortality. These diseases have gained much attention due to their complications, and therefore novel approaches with fewer side effects are an important research topic. Free radicals and oxidative stress are involved in the molecular mechanisms of several diseases. Antioxidants can scavenge free radicals and mitigate their adverse effects. One of the most important antioxidant enzymes are paraoxonases (PONs). These enzymes perform a wide range of physiological activities ranging from drug metabolism to detoxification of neuroleptics. Paraoxonase-1 (PON1) is produced in the liver and then transferred to the bloodstream. It has been demonstrated that PON1 could have beneficial effects in numerous diseases such as atherosclerosis, CVD, diabetes mellitus, and neurodegenerative diseases by modulating relevant signalling pathways involved in inflammation and oxidative stress. These pathways include peroxisome proliferator-activated receptor gamma (PPAR-γ) and protein kinase B/nuclear factor kappa-light-chain-enhancer of activated B cells (AKT/NF-κB)-dependent signalling pathways. Increasing PON1 could potentially have protective effects and reduce the incidence of various diseases by modulating these signalling pathways. Several studies have reported that dietary factors are able to modulate PON1 expression and activity. This review aimed at summarizing the state of the art on the effects of dietary phytochemicals on PON1 enzyme activity and the relevant signalling pathways in different diseases.

The effect of purple-black barberry (Berberis integerrima) on blood pressure in subjects with cardiovascular risk factors: a randomized controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Berberis integerrima commonly known as "barberry" belongs to the Berberidaceae family and has been used as a medicinal plant in Iranian traditional medicine.

AIM OF THE STUDY

Our aim in this study was to investigate the effects of barberry consumption on blood pressure (BP).

MATERIALS AND METHODS

Eighty-four medicated hypertensive patients were selected and randomly allocated to barberry and placebo groups. The barberry group received 10 g/day dried purple-black barberry powder, once daily, for 2-months. Systolic, diastolic, and mean arterial BP was assessed through 24-h ambulatory BP monitoring before and after 2-month treatment. The estimation of sodium and potassium intake was done through measurement of sodium and potassium in 24-h urinary samples. Plasma and urinary nitrite, and nitrate (NOx) levels, as well as plasma angiotensin-converting enzyme (ACE) activity, were also determined.

RESULTS

Seventy-eight participants with an average age of 54.12 ± 10.32 years and BMI of 27.93 ± 2.22 kg/m² completed the study. There was no significant difference in body weight, physical activity, and the 24-h urinary sodium and potassium excretion between the two groups before and after the study. After adjusting for baseline values and changes in sodium intake, systolic, and mean arterial BP decreased significantly in the barberry group compared to the placebo group (p = 0.015 and p = 0.008, respectively). Plasma NOx levels and ACE activity were not different between the two groups, but urinary NOx was increased significantly in the barberry group compared to the placebo group (p = 0.008).

CONCLUSIONS

In patients treated with antihypertensive drugs, daily consumption of purple-black barberry can be effective in improving systolic BP control.

The effect of barberry (Berberis integerrima) on lipid profile and systemic inflammation in subjects with cardiovascular risk factors: a randomized controlled trial

Background

Despite significant advances in the management of cardiovascular disease (CVDs), there is still a large burden of CVD in the world. The inclusion of functional foods in the diet may provide beneficial effects on CVD. Purple-black barberry due to its richness in anthocyanins and berberine has shown beneficial effects on cardiometabolic factors. We investigated the effects of barberry on plasma lipids as well as inflammatory biomarkers in subjects with cardiovascular risk factors.

Methods

This was an 8-weeks, single-blinded, randomized controlled clinical trial that the participants were randomly assigned to a barberry (10 g/day dried barberry) or placebo group. At baseline and end of the study, plasma lipid profiles including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), small-dense LDL-C (sd-LDL-C), non-HDL-C, and TC/HDL-C, as well as inflammatory biomarkers including C-reactive protein (CRP) and interleukin-6 (IL-6), were determined. An intention-to-treat analysis was performed.

Results

Eighty-four participants were randomly assigned to study groups. The mean (± SD) participants' age was 54.06 ± 10.19 years. Body weight, body mass index (BMI), physical activity, and dietary intake were not different between the two groups at baseline and the end of the study. After adjusting for baseline values, we observed a significant decrease in plasma levels of TG, TC, LDL-C, sd-LDL-C, non-HDL-C, and TC/HDL-C (p < 0.001, p = 0.011, p = 0.015, p = 0.019, p = 0.004, and p = 0.039 respectively) as well as CRP (p = 0.020) in the barberry group compared to the placebo group.

Conclusions

Our results indicate that purple-black barberry consumption decreases plasma levels of CRP and improves lipid profile in subjects with cardiovascular risk factors.

Trial registration

This clinical trial was registered at ClinicalTrials.gov (NCT number: NCT04084847).

Modification of High-Density Lipoprotein Functions by Diet and Other Lifestyle Changes: A Systematic Review of Randomized Controlled Trials

High-density lipoprotein (HDL) functional traits have emerged as relevant elements that may explain HDL antiatherogenic capacity better than HDL cholesterol levels. These properties have been improved in several lifestyle intervention trials. The aim of this systematic review is to summarize the results of such trials of the most commonly used dietary modifications (fatty acids, cholesterol, antioxidants, alcohol, and calorie restriction) and physical activity. Articles were screened from the Medline database until March 2021, and 118 randomized controlled trials were selected. Results from HDL functions and associated functional components were extracted, including cholesterol efflux capacity, cholesteryl ester transfer protein, lecithin-cholesterol acyltransferase, HDL antioxidant capacity, HDL oxidation status, paraoxonase-1 activity, HDL anti-inflammatory and endothelial protection capacity, HDL-associated phospholipase A2, HDL-associated serum amyloid A, and HDL-alpha-1-antitrypsin. In mainly short-term clinical trials, the consumption of monounsaturated and polyunsaturated fatty acids (particularly omega-3 in fish), and dietary antioxidants showed benefits to HDL functionality, especially in subjects with cardiovascular risk factors. In this regard, antioxidant-rich dietary patterns were able to improve HDL function in both healthy individuals and subjects at high cardiovascular risk. In addition, in randomized trial assays performed mainly in healthy individuals, reverse cholesterol transport with ethanol in moderate quantities enhanced HDL function. Nevertheless, the evidence summarized was of unclear quality and short-term nature and presented heterogeneity in lifestyle modifications, trial designs, and biochemical techniques for the assessment of HDL functions. Such findings should therefore be interpreted with caution. Large-scale, long-term, randomized, controlled trials in different populations and individuals with diverse pathologies are warranted.

Role of Polyphenol in Regulating Oxidative Stress, Inflammation, Fibrosis, and Apoptosis in Diabetic Nephropathy

Diabetic nephropathy (DN) is known as one of the driving sources of end-stage renal disease (ESRD). DN prevalence continues to increase in every corner of the world andthat has been a major concern to healthcare professionals as DN is the key driver of diabetes mellitus (DM) morbidity and mortality. Hyperglycaemia is closely connected with the production of reactive oxygen species (ROS) that cause oxidative stress response as well as numerous cellular and molecular modifications. Oxidative stress is a significant causative factor to renal damage, as it can activate other immunological pathways, such as inflammatory, fibrosis, and apoptosis pathways. These pathways can lead to cellular impairment and death as well as cellular senescence. Natural substances containing bioactive compounds, such as polyphenols, have been reported to exert valuable effects on various pathological conditions, including DM. The role of polyphenols in alleviating DN conditions has been documented in many studies. In this review, the potential of polyphenols in ameliorating the progression of DN via modulation of oxidative stress, inflammation, fibrosis, and apoptosis, as well as cellular senescence, has been addressed. This information may be used as the strategies for the management of DN and development as nutraceutical products to overcome DN development.

Bioactive Foods and Medicinal Plants for Cardiovascular Complications of Type II Diabetes: Current Clinical Evidence and Future Perspectives

Cardiovascular diseases (CVDs) are the main cause of mortality in type 2 diabetes mellitus (T2DM); however, not all patients are fully satisfied with the current available treatments. Medicinal plants have been globally investigated regarding their effect in CVD, yet the field is far from getting exhausted. The current paper aims to provide an evidence-based review on the clinically evaluated medicinal plants and their main therapeutic targets for the management of CVD in T2DM. Electronic databases including PubMed, Cochrane, Embase, Scopus, and Web of Science were searched from 2000 until November 2019, and related clinical studies were included. Lipid metabolism, glycemic status, systemic inflammation, blood pressure, endothelial function, oxidative stress, and anthropometric parameters are the key points regulated by medicinal plants in T2DM. Anti-inflammatory and antioxidant properties are the two most important mechanisms since inflammation and oxidative stress are the first steps triggering a domino of molecular pathological pathways leading to T2DM and, subsequently, CVD. Polyphenols with potent antioxidant and anti-inflammatory effects, essential oil-derived compounds with vasorelaxant properties, and fibers with demonstrated effects on obesity are the main categories of phytochemicals beneficial for CVD of T2DM. Some medicinal plants such as garlic (Allium sativum) and milk thistle (Silybum marianum) have strong evidences regarding their beneficial effects; however, others have low level of evidence which reveals the need for further clinical studies with larger sample sizes and longer follow-up periods to confirm the safety and efficacy of medicinal plants for the management of CVD in T2DM.

Carbamylated Erythropoietin Alleviates Kidney Damage in Diabetic Rats by Suppressing Oxidative Stress

The oxidative stress response plays an important role in the occurrence and development of diabetic kidney disease (DKD). It has become a new treatment target for DKD. In the current study, the effects of carbamylated erythropoietin (CEPO) on renal oxidative stress and damage in diabetic rats were examined. Thirty Sprague Dawley rats were intraperitoneally administered with 60 mg/kg streptozotocin to establish the diabetes model. The diabetic rats were randomly allocated into 4 groups (n=6 each): diabetes model group (DM group), DM + CEPO treatment group (DC group), DM + CEPO + EPO receptor (EPOR) blocking peptide treatment group (DCEB group), and DM + CEPO + CD131 blocking peptide treatment group (DCCB group). Meanwhile, a normal control group (NC group, n=6) was set up. Kidney tissues and blood samples were obtained for evaluation of oxidative stress and renal function. The results showed that diabetic rats exhibited increased oxidative stress in the kidney and early pathological changes associated with DKD. Treatment with CEPO reduced oxidative stress and attenuated renal dysfunction. However, diabetic rats treated with the combination of CEPO and EPOR blocking peptide or CD131 blocking peptide showed increased oxidative stress and reduced renal function when compared with CEPO treatment alone group. These results suggested that CEPO can protect against kidney damage in DKD by inhibiting oxidative stress injury via EPOR-CD131 heterodimers.

The effect of barberry (Berberis vulgaris) consumption on flow-mediated dilation and inflammatory biomarkers in patients with hypertension: A randomized controlled trial

Hypertension is considered as an important cardiovascular risk factor and evidence suggests that hypertension and endothelial dysfunction reinforce each other. Polyphenol-rich foods, such as barberry can reduce the risk of cardiovascular disease. Our aim was to investigate the effects of barberry consumption on vascular function and inflammatory markers in hypertensive subject. In this randomized controlled parallel trial, 84 hypertensive subjects of both genders (aged 54.06 ± 10.19 years; body mass index 28.02 ± 2.18 kg/m2 ) were randomly allocated to consume barberry (10 g/day dried barberry) or placebo for 8 weeks. Before and after the intervention, changes in brachial flow-mediated dilation (FMD) and plasma macrophage/monocyte chemo-attractant protein-1 (MCP-1), vascular cellular adhesion molecule-1, and intracellular adhesion molecule-1 (ICAM-1) were measured. An intention-to-treat analysis was performed. Compared to placebo (n = 42), barberry consumption (n = 42) improved FMD (B [95% CI] was 6.54% [4.39, 8.70]; p < .001) and decreased plasma ICAM-1 (B [95% CI] was -1.61 ng/ml [-2.74, -0.48]; p = .006). MCP-1 was significantly lower in the barberry group compared with the placebo group (B [95% CI] was -37.62 pg/ml [-72.07, -3.17]; p = .033). Our results indicate that barberry consumption improves FMD and has a beneficial effect on plasma ICAM-1 and MCP-1 in hypertensive patients. This trial was registered at the Iranian Registry of Clinical Trial (IRCT) with number IRCT20160702028742N8.

Functional Food and Bioactive Compounds on the Modulation of the Functionality of HDL-C: A Narrative Review

Cardiovascular diseases (CVD) remain a serious public health problem and are the primary cause of death worldwide. High-density lipoprotein cholesterol (HDL-C) has been identified as one of the most important molecules in the prevention of CVD due to its multiple anti-inflammatories, anti-atherogenic, and antioxidant properties. Currently, it has been observed that maintaining healthy levels of HDL-C does not seem to be sufficient if the functionality of this particle is not adequate. Modifications in the structure and composition of HDL-C lead to a pro-inflammatory, pro-oxidant, and dysfunctional version of the molecule. Various assays have evaluated some HDL-C functions on risk populations, but they were not the main objective in some of these. Functional foods and dietary compounds such as extra virgin olive oil, nuts, whole grains, legumes, fresh fish, quercetin, curcumin, ginger, resveratrol, and other polyphenols could increase HDL functionality by improving the cholesterol efflux capacity (CEC), paraoxonase 1 (PON1), and cholesteryl ester transfer protein (CETP) activity. Nevertheless, additional rigorous research basic and applied is required in order to better understand the association between diet and HDL functionality. This will enable the development of nutritional precision management guidelines for healthy HDL to reduce cardiovascular risk in adults. The aim of the study was to increase the understanding of dietary compounds (functional foods and bioactive components) on the functionality of HDL.

Effect of barberry (Berberis vulgaris) consumption on blood pressure, plasma lipids, and inflammation in patients with hypertension and other cardiovascular risk factors: study protocol for a randomized clinical trial

Background

Cardiovascular diseases (CVDs) remain the leading causes of morbidity and mortality in the world. Hypertension is an important and prevalent cardiovascular risk factor. The present study will be conducted to investigate the effect of barberry as a cardio-protective fruit on the blood pressure in patients with hypertension and other CVD risk factors. Furthermore, plasma concentrations of lipids and inflammatory biomarkers will be evaluated.

Methods/design

This is an 8-week, prospective, single-blinded, parallel assigned, randomized controlled clinical trial (RCT) in which eligible men and women with hypertension and other cardiovascular risk factors will be randomized to either placebo powder (PP; containing 9 g maltodextrin, 1 g citric acid, 1 g milled sucrose and edible red color (n = 37)) or barberry powder (BP; containing 10 g milled dried barberry and 1 g of milled sucrose (n = 37)) groups. At baseline and after 8 weeks of intervention, plasma lipids and inflammatory markers, 24-h urinary nitrite/nitrate and sodium excretion, and 24-h ambulatory blood pressure monitoring (ABPM) will be measured. Anthropometric measures and dietary assessment will be performed as well. Data analysis will be done using SPSS version-21 software.

Discussion

The interest in natural and functional food products has increased globally. This RCT will add to the growing literature for the potential antihypertensive, lipid-lowering, and anti-inflammatory effects of barberry in humans.

Trial registration

ClinicalTrials.gov (NCT number) NCT04084847. Registered on 10 December 2019.

The effect of barberry (Berberis vulgaris L.) supplementation on blood pressure: A systematic review and meta-analysis of the randomized controlled trials

OBJECTIVE

We identified and quantified the results of randomized clinical trials by examining the effect of barberry supplementation on blood pressure.

METHODS

We conducted a comprehensive search in the medical bibliographic database up to May 2020 on randomized clinical trials investigating the effect of barberry supplementation on adult blood pressure. Intensive literature searches and data extraction according to a prefixed scheme was performed independently by two investigators.

RESULTS

Through 5 randomized clinical trial studies, 350 subjects with 175 cases for the intervention group and 175 cases for control group were included in our study. The intervention period ranged from 4 to 12 weeks. In general, barberry supplementation did not have a significant effect on systolic blood pressure (WMD: -4.15 mmHg; 95 % CI: -10.3, 1.99, P = 0.185) and diastolic blood pressure (WMD: -1.22 mmHg; 95 % CI: -6.26, 3.82, P = 0.635). Our study was heterogeneous and subgroup analysis did not eliminate heterogeneity.

CONCLUSION

Totally, based on this study, we cannot conclude that barberry supplementation has beneficial effects on blood pressure. Also, all included studies had limitations such as different in geographical situations, Dietary of participants, health conditions, and pharmacological forms of berberis. Therefore, further study in this area is recommended.

Effect of hydroalcoholic extract of Berberis integerrima and resveratrol on ovarian morphology and biochemical parameters in Letrozole-induced polycystic ovary syndrome rat model: An experimental study

BACKGROUND

Resveratrol and Berberis integerrima (B. integerrima) are known to be natural antioxidants and regulators of human metabolism. However, the effects of resveratrol and B. integerrima on the ovarian morphology in polycystic ovary syndrome (PCOS) are not obvious.

OBJECTIVE

This study aimed to determine the effect of the hydroalcoholic extract of B. integerrima in combination with resveratrol on some biochemical parameters and ovarian morphology in the letrozole-induced PCOS rat.

MATERIALS AND METHODS

Seventy adult female Sprague-Dawley rats aged 10-12 weeks weighing 200 ± 20 gr were randomly divided into seven groups (n = 10/each). Group I): normal; Group II): vehicle; Group III): letrozole-induced PCOS 1 mg/kg letrozole orally, rats receiving 1 cc normal saline orally; Group IV): PCOS + receiving 150 mg/kg metformin orally; Group V): PCOS + receiving 20 mg/kg resveratrol orally; Group VI): PCOS + 3 gr/kg barberry orally; and Group VII): PCOS + receiving 3 gr/kg barberry and 20 mg/kg resveratrol orally. All animals were followed-up for 63 days. The biochemical parameters and histological assessments of ovaries were performed.

RESULTS

Resveratrol alone and/or in combination with B. integerrima treatment in rats led to a significant decrease in low-density lipoprotein, triglyceride, malondialdehyde, and tumor necrosis factor-alpha concentrations (p = 0.02). The groups IV, V, VI, and VII showed a decrease in insulin resistance and an increase in the superoxide dismutase, total antioxidant capacity, and high-density lipoprotein (p = 0.01). No significant difference was observed between the level of serum glucose in the treatment groups. Number of cystic follicles had a significant decrease in barberry, resveratrol, and their combination groups (p < 0.001).

CONCLUSION

Resveratrol, B. integerrima, and their combination as natural products with fewer side effects might be effective as an alternative medicine in treatment of PCOS.

Effects of chronic consumption of specific fruit (berries, citrus and cherries) on CVD risk factors: a systematic review and meta-analysis of randomised controlled trials

Purpose

This review aims to compare the magnitude of the effects of chronic consumption of fruits; specifically berries, citrus and cherries on cardiovascular disease (CVD) risk factors.

Methods

PubMed, Web of Science, Scopus, and psycARTICLES were searched from inception until January 2020. Forty-five chronic (≥ 1 week) randomised controlled trials assessing CVD risk factors including endothelial (dys)function, blood pressure (BP), blood lipids and inflammatory biomarkers were included.

Results

Investigated interventions reported improvements in endothelial function (n = 8), inflammatory biomarkers and lipid status (n = 14), and BP (n = 10). Berries including juice of barberry, cranberry, grape, pomegranate, powder of blueberry, grape, raspberry and freeze-dried strawberry significantly reduced SBP by 3.68 mmHg (95% CI − 6.79 to − 0.58; P = 0.02) and DBP by 1.52 mmHg (95% CI − 2.87 to − 0.18, P = 0.04). In subgroup analysis, these associations were limited to cranberry juice (SBP by 1.52 mmHg [95% CI − 2.97 to − 0.07; P = 0.05], DBP by 1.78 mmHg [95% CI − 3.43 to − 0.12, P = 0.04] and cherry juice (SBP by 3.11 mmHg [95% CI − 4.06 to − 2.15; P = 0.02]). Berries also significantly elevated sVCAM-1 levels by 14.57 ng/mL (85% CI 4.22 to 24.93; P = 0.02).

Conclusion

These findings suggest that supplementing cranberry or cherry juice might contribute to an improvement in blood pressure. No other significant improvements were observed for other specified fruits. More research is warranted comparing different classes of fruit and exploring the importance of fruit processing on their cardiovascular-protective effects.

Electronic supplementary material

The online version of this article (10.1007/s00394-020-02299-w) contains supplementary material, which is available to authorized users.

The effect of barberry (Berberis vulgaris L.) on glycemic indices: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

We performed a meta-analysis to evaluate the efficacy of barberry (Berberis vulgaris L.) supplementation on glycemic indices in adults.

METHODS

A comprehensive search was conducted in PubMed, Scopus, Cochrane Library, and ISI Web of Science from inception up to January 2020, to identify randomized controlled trials (RCTs) investigating the effect of barberry supplementation on glycemic markers including fasting blood sugar (FBS) concentrations, insulin levels, homeostatic model assessment for insulin resistance (HOMA-IR), and glycosylated hemoglobin (HbA1c) percentage. The results of this meta-analysis were reported, based on the random effects model.

RESULTS

In total, 7 studies, comprising 452 participants, were included in the systematic review. The meta-analysis revealed that barberry significantly reduces insulin levels (Hedges's: -0.67; 95% CI: -1.31 to -0.03, P = 0.04, I² = 73.3%). However, no considerable changes was observed for FBS levels (WMD: -8.06 mg/dL; 95% CI: -20.46 to 4.33, P = 0.23, I² = 96.1%), HbA1c percentage (WMD: -0.83 %; 95% CI: -2.33 to 0.67, P = 0.27, I² = 88.3%), and HOMA-IR index (WMD: -0.55; 95% CI: -1.60 to 0.50, P = 0.30, I² = 99.4%).

CONCLUSION

The present study suggests that although barberry supplementation significantly improves insulin levels; however, other glycemic indices might not be affected. However, more high-quality RCTs with longer duration are needed to further clarify the effects of barberry on blood glucose control, especially among patients with diabetes.

Effects of berberine and barberry on anthropometric measures: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Despite controversies, no study has systematically summarized findings from earlier studies on the effect of berberine and barberry on anthropometric measures. Therefore, the current systematic review and meta-analysis was conducted on the effect of berberine and barberry on body mass index (BMI), body weight (BW), waist circumference (WC) and waist-hip ratio (WHR) in adults.

METHODS

Relevant studies, published up to August 2019, were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase and Google Scholar. All randomized clinical trials investigating the effect of berberine and barberry on the anthropometric measures including BMI, BW, WC or/and WHR were included.

RESULTS

Out of 252 citations, 12 trials that enrolled 849 subjects were included. Berberine and barberry resulted in no significant change in BMI (Weighted mean differences (WMD): -0.16 kg/m²; 95 % CI: -0.43 to 0.11, P = 0.247), BW (WMD: -0.11 kg; 95 % CI: -0.13 to 0.91, P = 0.830), and berberine resulted in not significant in WC (WMD: -0.58 cm; 95 % CI: -1.89 to 0.72, P = 0.379) and significant reduction in WHR (WMD: -0.03; 95 % CI: -0.04 to -0.01, P < 0.0001).

CONCLUSION

We found a significant reduction in WHR following berberine consumption in adults. Further clinical trials with high quality according to challenges mentioned seem to be helpful to use berberine and barberry as a supplement for certain health conditions, efficiently.

The effect of resveratrol supplementation on serum levels of asymmetric de-methyl-arginine and paraoxonase 1 activity in patients with type 2 diabetes: A randomized, double-blind controlled trial

The present study sought to investigate the effect of micronized resveratrol supplementation on serum levels of asymmetric de-methyl-arginine (ADMA) and paraoxonase-1 (PON1) activity in patients with type 2 diabetes (T2D). In this double-blinded randomized trial, 76 patients with T2D were recruited. Participants were randomly assigned to consume 1,000 mg resveratrol or placebo capsules (methylcellulose) per day, for 8 weeks. Serum levels of ADMA and PON1 enzyme activity were measured at the beginning and end of the intervention using the enzyme-linked immunosorbent assay method. In total, 71 participants completed the study. Our results showed that resveratrol significantly decreased serum levels of ADMA (-0.16 ± 0.11, p < .001) and improved PON1 enzyme activity (15.39 ± 13.99, p < .001) compared with placebo, after adjusting for confounding factors (age, sex, and baseline body mass index). Our findings suggest that 8-week resveratrol supplementation may produce beneficial effects on serum levels of ADMA and PON1 enzyme activity in patients with T2DM. However, further research is needed to confirm the veracity of these results.

Safety and efficacy of Berberis integerrima root extract in patients with type 2 diabetes. A parallel intervention based triple blind clinical trial

Purpose

To evaluate the safety and efficacy of methanol extract of Berberis integerrima root on type 2 diabetes compared to metformin.

Methods

In a parallel triple blind clinical trial, 80 type 2 diabetic patients,, were randomized into two groups (treated with Berberis integerrima root, 480 mg (oral), compared to control group treated with metformin 1000 mg daily). Efficacy was evaluated by fasting and prandial glucose and HbA1c and side effects confirmed by physical examination, biology and hematology tests and urinalysis on days 15, 45 and 90. They were followed for 3 months.

Results

Two hundred and eighteen patients were recruited and 80 (55female and 25 male) patients randomized in two groups and 60 patient were analysed. The mean age of patients was 51.8 ± 9.3 and 46.5 ± 10 in the experimental (Berberis integerrima ) and control (metformin) groups respectively (P = 0.02). The mean HbA1c at baseline was 8.1 ± 1.6% and 7.9 ± 1.6% for B. integerrima and metformin group respectively (P = 0.53), and there was no significant difference between the two groups (7.5 vs. 7.2) after 3 months (P = 0.34).Weight loss was observed in both groups compared to baseline.No adverse event led to preventing the study was reported.

Conclusion

Berberis integerrima root not only was effective as much as metformin in reducing blood glucose and controlling type 2 diabetes but also, no specific side effect was reported (in short term).So, it might be an effective and safe complementary therapy in diabetic patients.Iranian Research and Clinical Trial (IRCT) registeration number; 201,207,191,774 N5.Funding: Vice chancellor for research, Physiology Research Center of Kerman University of Medical Sciences and the Exir pharmaceutical company.

Importance of paraoxonase 1 (PON1) as an antioxidant and antiatherogenic enzyme in the cardiovascular complications of type 2 diabetes: Genotypic and phenotypic evaluation

Oxidant-antioxidant imbalance is involved in the etiology of different diseases, including cardiovascular diseases (CVDs), liver disorders, kidney diseases, cancers and diabetes mellitus. Antioxidant enzymes play a key role in striking an oxidant-antioxidant balance. Moreover, paraoxonase 1 (PON1) is an antioxidant enzyme that binds with high-density lipoprotein (HDL) in the circulation, and antioxidant and antiaterogenic properties of this lipoprotein are significantly associated with PON1. Research suggests PON1 contributes to the pathogenesis of certain human diseases such as type 2 diabetes (T2D). The association between PON1 and T2D appear to be reciprocal so that the disease significantly decreases PON1 levels and in turn, the genetics of PON1 may have a role the risk of susceptibility to T2D. Several factors that reduce the activity and concentration of PON1 in patients with T2D include increased glycation and loss-of-function polymorphisms. The genotypic and phenotypic evaluations of PON1 are therefore crucial for assessing the risk of cardiovascular complications in these patients, and strategies for increasing or restoring PON1 levels are useful for reducing or preventing their cardiovascular complications as their main cause of mortality. The present review aimed at discussing and emphasizing the key role of PON1 in T2D as a silent and dangerous disease.

Dietary berries, insulin resistance and type 2 diabetes: an overview of human feeding trials

Dietary berries are a rich source of several nutrients and phytochemicals and in recent years, accumulating evidence suggests they can reduce risks of several chronic diseases, including type 2 diabetes (T2D). The objective of this review is to summarize and discuss the role of dietary berries (taken as fresh, frozen, or other processed forms) on insulin resistance and biomarkers of T2D in human feeding studies. Reported feeding trials involve different berries taken in different forms, and consequently differences in nutritional or polyphenol composition must be considered in their interpretation. Commonly consumed berries, especially cranberries, blueberries, raspberries and strawberries, ameliorate postprandial hyperglycemia and hyperinsulinemia in overweight or obese adults with insulin resistance, and in adults with the metabolic syndrome (MetS). In non-acute long-term studies, these berries either alone, or in combination with other functional foods or dietary interventions, can improve glycemic and lipid profiles, blood pressure and surrogate markers of atherosclerosis. Studies specifically in people with T2D are few, and more knowledge is needed. Nevertheless, existing evidence, although sparse, suggests that berries have an emerging role in dietary strategies for the prevention of diabetes and its complications in adults. Despite the beneficial effects of berries on diabetes prevention and management, they must be consumed as part of a healthy and balanced diet.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

Polyphenols targeting diabetes via the AMP-activated protein kinase pathway; future approach to drug discovery

Regarding the widespread progression of diabetes, its related complications and detrimental effects on human health, investigations on this subject seems compulsory. AMP-activated protein kinase (AMPK) is a serine/threonine kinase and a key player in energy metabolism regulation. AMPK is also considered as a prime target for pharmaceutical and therapeutic studies on disorders such as diabetes, metabolic syndrome and obesity, where the body energy homeostasis is imbalanced. Following the activation of AMPK (physiological or pharmacological), a cascade of metabolic events that improve metabolic health is triggered. While there are several publications on this subject, this is the first report that has focused solely on polyphenols targeting diabetes via AMPK pathway. The multiple characteristics of polyphenolic compounds and their favorable influence on diabetes pathogenesis, as well as their intersections with the AMPK signaling pathway, indicate that these compounds have a beneficial effect on the regulation of glucose homeostasis. PPs could potentially occupy a significant position in the future anti-diabetic drug market.

Barberry in the treatment of obesity and metabolic syndrome: possible mechanisms of action

Obesity is a consequence of an imbalance between energy intake and energy expenditure. It affects people of both genders and all age groups, ethnicity and socioeconomic groups, and in developed and developing countries. Obesity is often accompanied by the metabolic syndrome (MetS). MetS is characterized by a clustering of cardiovascular risk factors, including high blood pressure, adiposity, dyslipidemia and glucose intolerance, which together increase the risk of atherosclerotic cardiovascular disease, type 2 diabetes mellitus and other causes of mortality. Nowadays, there is a growing interest in the use of plant-based agents instead of synthetic drugs to manage chronic diseases such as MetS; one such example is Berberis vulgaris. B. vulgaris contains isoquinonline alkaloids such as berberine, berberrubine and berbamine. Recent studies have proved that berberine exhibits pharmacological activities and positive effects on the risk factors of obesity and MetS. We have reviewed original articles related to the possible molecular mechanisms of action of berberine on obesity and MetS. Berberine suppresses adipocyte differentiation and decreases obesity. It also regulates glucose metabolism via decreasing insulin resistance and increasing insulin secretion. Other effects of berberine include antihyperlipidemic and antihypertensive activities and endothelial protection.