Nutraceutical Effects on Glucose and Lipid Metabolism in Patients with Impaired Fasting Glucose: A Pilot, Double-Blind, Placebo-Controlled, Randomized Clinical Trial on a Combined Product

Nutraceuticals and Supplements in Management of Prediabetes and Diabetes

Dysglycemia is a condition preceding diabetes mellitus. The two situations inherent in this condition are called impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). If one of these situations is found in the patient, after the advice of an appropriate diet and physical activity, the addition of nutraceuticals or supplements can be considered, which can stop or delay the progression to diabetes mellitus over time. The purpose was to compile a systematic review about the use of nutraceuticals for treating diabetes and prediabetes and to offer a valuable resource for colleagues working on this crucial subject, thereby improving patient health. The added value of the paper compared to other reviews is that it was written by experts appointed by five different scientific societies dealing with diabetes, nutrition, and complications.

Impact of Berberine or Berberine Combination Products on Lipoprotein, Triglyceride and Biological Safety Marker Concentrations in Patients with Hyperlipidemia: A Systematic Review and Meta-Analysis

Monoclonal antibody Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) inhibitors reduce total cholesterol (TC), low density lipoproteins (LDL), high density lipoproteins (HDL), and triglycerides (TG). We assessed the ability of berberine, a natural PCSK9 inhibitor, to reduce lipid concentrations either alone or combined with other nutraceuticals. We searched PubMed, Scopus and EMBASE from inception to September 30th, 2022 for randomized controlled trials (RCTs) assessing 8-18 wk of berberine therapy on. A total of 41 RCTs with 4,838 patients met our inclusion criteria. Berberine containing products significantly reduced TC (MD -17.42 mg/dL [95%CI: -22.91 to -11.93]), LDL (MD -14.98 mg/dL [95%CI: -20.67 to -9.28]), and TG (MD -18.67 mg/dL [95%CI: -25.82 to -11.51]) while raising HDL (MD 1.97 mg/dL [95%CI: 1.16 to 2.78]) versus control (I2 > 72% for all analyses). Products with berberine alone had less robust effects on TC (MD -12.08 mg/dL [95%CI: -21.79 to -2.37]), LDL (MD -9.26 mg/dL [95%CI: -20.31 to 1.78]), and HDL (MD 1.38 mg/dL [95%CI: -1.27 to 4.03]) but TG effects were similar (MD -17.40 mg/dL [95%CI: -32.57 to -2.23]). Berberine along with red yeast rice reduced TC (MD -19.62 mg/dL [95%CI: -28.56 to -10.68]) and LDL (MD -18.79 mg/dL [95%CI: -28.03 to -9.54]) as did combination therapy with Silybum maranium for TC (MD -31.81 mg/dL [95%CI: -59.88 to -3.73]) and LDL (MD -30.82 mg/dL [95%CI: -56.48 to -5.16]). Berberine, alone or with other nutraceuticals, can provide a modest positive impact on lipid concentrations.

Role of Turmeric and Curcumin in Prevention and Treatment of Chronic Diseases: Lessons Learned from Clinical Trials

Turmeric (Curcuma longa) has been used for thousands of years for the prevention and treatment of various chronic diseases. Curcumin is just one of >200 ingredients in turmeric. Almost 7000 scientific papers on turmeric and almost 20,000 on curcumin have been published in PubMed. Scientific reports based on cell culture or animal studies are often not reproducible in humans. Therefore, human clinical trials are the best indicators for the prevention and treatment of a disease using a given agent/drug. Herein, we conducted an extensive literature survey on PubMed and Scopus following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The keywords "turmeric and clinical trials" and "curcumin and clinical trials" were considered for data mining. A total of 148 references were found to be relevant for the key term "turmeric and clinical trials", of which 70 were common in both PubMed and Scopus, 44 were unique to PubMed, and 34 were unique to Scopus. Similarly, for the search term "curcumin and clinical trials", 440 references were found to be relevant, of which 70 were unique to PubMed, 110 were unique to Scopus, and 260 were common to both databases. These studies show that the golden spice has enormous health and medicinal benefits for humans. This Review will extract and summarize the lessons learned about turmeric and curcumin in the prevention and treatment of chronic diseases based on clinical trials.

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.

The role of selected nutraceuticals in management of prediabetes and diabetes: An updated review of the literature

Dysglycemia is a disease state preceding the onset of diabetes and includes impaired fasting glycemia and impaired glucose tolerance. This review aimed to collect and analyze the literature reporting the results of clinical trials evaluating the effects of selected nutraceuticals on glycemia in humans. The results of the analyzed trials, generally, showed the positive effects of the nutraceuticals studied alone or in association with other supplements on fasting plasma glucose and post-prandial plasma glucose as primary outcomes, and their efficacy in improving insulin resistance as a secondary outcome. Some evidences, obtained from clinical trials, suggest a role for some nutraceuticals, and in particular Berberis, Banaba, Curcumin, and Guar gum, in the management of prediabetes and diabetes. However, contradictory results were found on the hypoglycemic effects of Morus, Ilex paraguariensis, Omega-3, Allium cepa, and Trigonella faenum graecum, whereby rigorous long-term clinical trials are needed to confirm these data. More studies are also needed for Eugenia jambolana, as well as for Ascophyllum nodosum and Fucus vesiculosus which glucose-lowering effects were observed when administered in combination, but not alone. Further trials are also needed for quercetin.

Polysaccharide-Rich Red Algae (Gelidium amansii) Hot-Water Extracts Alleviate Abnormal Hepatic Lipid Metabolism without Suppression of Glucose Intolerance in a Streptozotocin/Nicotinamide-Induced Diabetic Rat Model

This study was designed to investigate the effects of polysaccharide-rich red algae (Gelidium amansii) hot-water extracts (GHE) on lipid and glucose metabolism in rats with streptozotocin (STZ)/nicotinamide (NA)-induced diabetes. Rats were divided into three groups: NC-normal control group), DM-diabetic group, and DG-diabetic group supplemented with GHE (5%). The experimental diet and drinking water were available ad libitum for 10 weeks. After the 10-week feeding duration, the body weight, liver weight, total adipose tissue weight, and hepatic TBARS and cholesterol levels were significantly increased, and hepatic glycogen content and adipose lipolysis rate were significantly decreased in the DM group, which could be effectively reversed by supplementation of GHE. However, GHE supplementation could not improve the glucose intolerance in DM rats. It was interesting to note that GHE supplementation could decrease the liver glucose-6-phosphotase activity, which was increased in DM rats. Taken together, these results suggested that GHE feeding may ameliorate abnormal hepatic lipid metabolism, but not glucose intolerance, in diabetic rats induced by STZ/NA.

Evaluation of the effect of curcumin and zinc co-supplementation on glycemic measurements, lipid profiles, and inflammatory and antioxidant biomarkers in overweight or obese prediabetic patients: a study protocol for a randomized double-blind placebo-controlled phase 2 clinical trial

BACKGROUND

The prevalence of prediabetes is increasing worldwide. Unfortunately, prediabetes is related to non-communicable diseases. A high risk of developing type 2 diabetes mellitus (T2DM) is reported in people with prediabetes. Curcumin, a polyphenol, might lead to its therapeutic role in obesity and some obesity-related metabolic diseases. Zinc is a trace element that plays a key role in the synthesis and action of insulin, carbohydrate metabolism, and decreasing inflammation. There has been no clinical trial of zinc and curcumin co-supplementation in patients with prediabetes. In previous studies, the single administration of zinc or curcumin has not been conducted on many of the studied markers in prediabetic patients.

METHODS

The purpose of this randomized double-blind placebo-controlled clinical trial is to investigate the effect of curcumin and zinc co-supplementation on glycemic measurements, lipid profiles, and inflammatory and antioxidant biomarkers among 84 prediabetic patients with body mass index (BMI) between 25 and 35. Also, liver enzyme, serum zinc, urine zinc, blood pressure, anthropometric parameters, quality of life, adherence to co-supplementation, the side effects of co-supplementation, physical activity, and dietary intake will be assessed. Women or men (18-50 years old for men and 18 years to before menopause for women) will be followed for 3 months (90 days). This study will be conducted at Yazd Diabetes Research Clinic, Shahid Sadoughi University of Medical Sciences.

DISCUSSION

A diet rich in antioxidants, polyphenols, and phytochemicals has been shown to have a beneficial role in prediabetes. According to the beneficial properties of curcumin or zinc and inadequate evidence, RCTs are needed to assess the effect of curcumin and zinc co-supplementation in native prediabetes patients. We hope the results of the present trial, negative or positive, fill this gap in the literature and facilitate the approach for a much larger, multi-center clinical trial. In conclusion, a synergic effect of co-supplementation along with a weight-loss diet may delay the progression to type 2 diabetes mellitus.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT) IRCT20190902044671N1 . Registered on 11 October 2019.

A Randomized, Double-Blinded, Placebo-Controlled, Clinical Study of the Effects of a Nutraceutical Combination (LEVELIP DUO®) on LDL Cholesterol Levels and Lipid Pattern in Subjects with Sub-Optimal Blood Cholesterol Levels (NATCOL Study)

Phytosterols and red yeast rice are largely studied cholesterol-lowering nutraceuticals, respectively inhibiting the bowel absorption and liver synthesis of cholesterol. Our aim was to test the effect of combined nutraceutical-containing phytosterols and red yeast rice vs. a placebo on the lipid profile. We performed a parallel arms, double-blind, placebo-controlled clinical trial, randomizing 88 moderately hypercholesterolemic subjects to treatment with a combined nutraceutical containing phytosterols (800 mg) and red yeast rice, standardized to contain 5 mg of monacolins from Monascus purpureus, with added niacin (27 mg) and policosanols (10 mg) (LEVELIP DUO^®), or placebo. The mean LDL-Cholesterol (LDL-C) change at Week 8 was −32.5 ± 30.2 mg/dL (−19.8%) in the combined nutraceutical group and 2.5 ± 19.4 mg/dL (2.3%) in the placebo group. The estimated between-group difference of −39.2 mg/dL (95% CI: −48.6; −29.8) indicates a statistically significant difference between treatments in favor of the combined nutraceutical (p < 0.0001). Total Cholesterol (TC), non-HDL cholesterol (non-HDL-C), Apolipoprotein B, TC/HDL-C and LDL-C/HDL-C improved in a similar way in the combined nutraceutical group only. No significant changes in other clinical and laboratory parameters were observed. In conclusion, the tested combined nutraceutical was well tolerated, while significantly reducing the plasma levels of LDL-C, TC, non-HDL-C, ApoB, TC/HDL-C and LDL-C/HDL-C ratios in mildly hypercholesterolemic patients. Trial registration (ClinicalTrials.gov): NCT03739242.

Nano-enabled personalized nutrition: Developing multicomponent-bioactive colloidal delivery systems

There is growing interest in the production of foods and beverages with nutrient and nutraceutical profiles tailored to an individual's specific nutritional requirements. In principle, these personalized nutrition products are formulated based on the genetics, epigenetics, metabolism, microbiome, phenotype, lifestyle, age, gender, and health status of a person. A challenge in this area is to create customized functional food and beverage products that contain the required combination of bioactive agents, such as lipids, proteins, carbohydrates, vitamins, minerals, nutraceuticals, prebiotics and probiotics. Nanotechnology may facilitate the development of these kind of products since it can be used to encapsulate one or more bioactive agent in a single colloidal delivery system. This delivery system may contain one or more different kinds of colloidal particle, specifically designed to protect each nutrient in the food, but then deliver it in a bioavailable form after ingestion. This review article provides an overview of the different kinds of bioactives that need to be delivered, as well as some of the challenges associated with incorporating them into functional foods and beverages. It then highlights how nanotech-enabled colloidal delivery systems can be developed to encapsulate multiple bioactive agents in a form suitable for functional food applications, particularly in the personalized nutrition field.

Impact of a short-term synbiotic supplementation on metabolic syndrome and systemic inflammation in elderly patients: a randomized placebo-controlled clinical trial

PURPOSE

The connection between gut microbiota imbalance, inflammation and its role in the pathogenesis of metabolic syndrome (MetS) clustering factors has been increasingly recognized. However, data on the efficacy of probiotics supplementation on MetS components are few and almost lacking in the elderly. To address this issue, we conducted a randomized, double-blind, placebo-controlled, parallel-group, clinical study on a large sample of MetS elderly patients.

METHODS

After 14 days of diet and physical activity standardization, 60 elderly patients were randomized to treatment with a synbiotic formula of Lactobacillus plantarum PBS067, Lactobacillus acidophilus PBS066 and Lactobacillus reuteri PBS072 with active prebiotics or placebo. Patients were evaluated anamnestically and by the execution of a physical examination and laboratory and haemodynamic analyses at the baseline and after 60 days of treatment. At enrollment and at the end of the trial, all enrolled patients complete the EuroQol-5 Dimension (EQ-5D) questionnaire.

RESULTS

Through the 2-month period of treatment, patients who received active treatment experienced a statistically significant improvement in waist circumference and in fasting plasma insulin, total cholesterol, high-density lipoprotein cholesterol, non-HDL-C, triglycerides (TG), low-density lipoprotein cholesterol, high-sensitivity C-reactive protein and tumor necrosis factor alpha serum levels, compared both to the baseline and the control group. Visceral adiposity index improvement in the synbiotic treatment group was significantly greater than in placebo group. Compared to baseline, treatment with synbiotics also significantly reduced mean arterial pressure and fasting plasma glucose. All treatment groups demonstrated a significant decrease in TG. TG reduction in the synbiotic group was significantly greater than in the control group. The EQ-5D VAS questionnaire significantly improved only in probiotics-treated subjects.

CONCLUSION

Treatment with a synbiotic formula of L. plantarum PBS067, L. acidophilus PBS066 and L. reuteri PBS072 with active prebiotics decreased MetS syndrome prevalence, several cardiovascular risk factors and markers of insulin resistance in elderly patients.

Nutraceutical Improves Glycemic Control, Insulin Sensitivity, and Oxidative Stress in Hyperglycemic Subjects: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

The aim of this research was to investigate the effects of nutraceuticals including bitter melon, fenugreek, cinnamon, alpha-lipoic acid, zinc, biotin, chromium, and cholecalciferol on glycemic control, insulin sensitivity, lipid profiles, oxidative stress, and inflammatory markers in hyperglycemia. The study design was a randomized, double-blind, placebo-controlled trial. Subjects with hyperglycemia were randomly divided into 2 groups. The treatment group ( n = 52) was given a nutraceutical and the control group ( n = 50) was provided with a placebo for 12 weeks. Fasting blood glucose (FBG), hemoglobin A1c (HbA1C), homeostatic model assessment of insulin resistance (HOMA-IR), lipid profiles, biomarkers of oxidative stress, and inflammation were assessed before and after the intervention at 6 weeks and 12 weeks. Nutraceutical supplementation demonstrated a statistically significant decrease in FBG (13.4% and 18.9%), HbA1C (6.5% and 11.3%), and HOMA-IR (28.9% and 35.2%) compared with the placebo. Moreover, low-density lipoprotein-cholesterol (LDL-C) level was significantly reduced in the nutraceutical group (7.1% and 9.3%). Furthermore, the nutraceutical significantly decreased oxidative stress markers, oxidized LDL-C (14.8% and 18.9%) and malondialdehyde (16.6% and 26.2%) compared with the placebo. In conclusion, this nutraceutical can improve glycemic control, insulin resistance, lipid profiles, and oxidative stress markers in hyperglycemic subjects. Therefore, it has the potential to decrease cardiovascular disease risk factors. Clinical trial registration: TCTR20180907001, www.clinicaltrials.in.th.

Antidiabetic Properties of Curcumin II: Evidence from In Vivo Studies

Type 2 diabetes mellitus (T2DM) is a growing metabolic disease characterized by insulin resistance and hyperglycemia. Current preventative and treatment approaches to insulin resistance and T2DM lack in efficacy, resulting in the need for new approaches to prevent and treat the disease. In recent years, epidemiological studies have suggested that diets rich in fruits and vegetables have beneficial health effects, including protection against insulin resistance and T2DM. Curcumin, a polyphenol found in turmeric, and curcuminoids have been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, neuroprotective, immunomodulatory and antidiabetic properties. The current review (II of II) summarizes the existing in vivo studies examining the antidiabetic effects of curcumin.

Mitochondrial lipoylation integrates age-associated decline in brown fat thermogenesis

Thermogenesis in brown adipose tissue (BAT) declines with age; however, what regulates this process remains poorly understood. Here, we identify mitochondria lipoylation as a previously unappreciated molecular hallmark of aged BAT in mice. Using mitochondrial proteomics, we show that mitochondrial lipoylation is disproportionally reduced in aged BAT through a post-transcriptional decrease in the iron-sulfur (Fe-S) cluster formation pathway. A defect in the Fe-S cluster formation by the fat-specific deletion of Bola3 significantly reduces mitochondrial lipoylation and fuel oxidation in BAT, leading to glucose intolerance and obesity. In turn, enhanced mitochondrial lipoylation by α-lipoic acid supplementation effectively restores BAT function in old mice, thereby preventing age-associated obesity and glucose intolerance. The effect of α-lipoic acids requires mitochondrial lipoylation via the Bola3 pathway and does not depend on the anti-oxidant activity of α-lipoic acid. These results open up the possibility to alleviate the age-associated decline in energy expenditure by enhancing the mitochondrial lipoylation pathway.

Effects of curcumin on glycemic control and lipid profile in prediabetes and type 2 diabetes mellitus: A systematic review and meta-analysis

Scope

Studies have demonstrated inconsistent effects of curcumin on glycemic outcomes and lipid parameters in patients with prediabetes and type 2 diabetes mellitus (T2DM). This study aimed to assess the effect of curcumin on glycemic control and lipid profile in prediabetes and T2DM.

Methods and results

A systematic search of randomized controlled trials (RCTs) was conducted from inception to June 2018 in electronic sources including AMED, ANZCTR, BioMed Central, CENTRAL, CINAHL, ClinicalTrials.gov, Expanded Academic Index, Google Scholar, ISRCTN, LILACS, MEDLINE, NCCIH, Science Direct, Scopus, Web of Science, and WHO ICTRP. Hand search was also performed. Of the total 486 records, four trials (N = 508) and eight trials (N = 646) were eligible for the meta-analysis of individuals with prediabetes and T2DM, respectively. Curcumin significantly reduced glycosylated hemoglobin (HbA1c) in prediabetics (MD: -0.9%, 95% CI: -1.7 to -0.1%, p = 0.03). Furthermore, T2DM subjects gained favorable reduction in both HbA1c (MD: -0.5%, 95% CI: -1.0 to -0.0%, p = 0.04) and fasting plasma glucose (MD: -11.7 mg/dL, 95% CI: -22.1 to -1.3 mg/dL, p = 0.03). Tendency of lipid profile improvement was also observed.

Conclusion

Our findings may encourage curcumin supplementation based on its meaningful effect on glycemic control and positive trend on lipid outcomes in prediabetes and T2DM.

Metabolic benefits of curcumin supplementation in patients with metabolic syndrome: A systematic review and meta-analysis of randomized controlled trials

The finding of studies on the effect of curcumin extract on metabolic factor in patients with metabolic syndrome has had arguable results. This systematic review with meta-analysis of randomized controlled trials (RCT) aimed to analyze the effect of curcumin/turmeric on metabolic factors in patients with metabolic syndrome. The PICO strategy was used to establish the guiding question of this review. Several databases for RCT were searched until September 2018. Of the 144 articles initially identified, seven trials met the eligibility criteria. A random-effects model with a mean weight difference (WMD) and a 95% confidence interval was performed for quantitative data synthesis. Pooled estimates of WMD were calculated between intervention and control groups using random-effects model in the presence of high level of heterogeneity between the studies. The results showed significant improvement of fasting blood glucose (p = 0.01), triglycerides (p < 0.001), high-density lipoprotein cholesterol (p = 0.003), and diastolic blood pressure (p = 0.007) levels. Curcumin was not associated with a significant change in waist circumference measurement (p = 0.6) and systolic blood pressure level (p = 0.269). Curcumin supplementation improves some components of metabolic syndrome.

Short-Term Effects of Dry Extracts of Artichokeand Berberis in Hypercholesterolemic Patients Without Cardiovascular Disease

Hypercholesterolemia represents one of the main reversible cardiovascular risk factors. In this pilot clinical trial, we have tested the short-term efficacy and safety of a new combined cholesterol-lowering nutraceutical containing artichoke dry extract and berberine at enhanced bioavailability in subjects with moderate polygenic hypercholesterolemia in primary prevention for cardiovascular disease. After 2 months of treatment, the tested nutraceutical induced a significant reduction in plasma total cholesterol (-19%), low-density lipoprotein cholesterol (-16%), non-high-density lipoprotein cholesterol (-19%) and triglyceride levels (-15%), in association with a standardized control diet. No side effect has been observed during the trial. In conclusion, on the short-term, the tested nutraceutical has been shown to be well tolerated and effective, even if not containing any statin-like compound.

Optimizing Lipid Pattern by Adding a Combined Nutraceutical or Pravastatin to Fenofibrate Treatment in Hypertriglyceridemic Subjects: Single Site, Randomized, Open-Label, Post-Market Clinical Investigation

INTRODUCTION

Fenofibrate is an effective and safe treatment for hypertriglyceridemia. However, after TG reduction a residual dyslipidemia could appear and require further treatment.

AIM

To comparatively evaluate the short-term tolerability and efficacy of a combined lipid-lowering nutraceutical and pravastatin 40 mg in fenofibrate treated patients.

METHOD

We prospectively enrolled 40 patients well-tolerating treatment with micronized fenofibrate 145 mg/day and with residual dyslipidemia (LDL-C > 115 mg/dL and TG > 150 mg/dL). Exclusion criteria have been type 2 diabetes, Familial Hypercholesterolemia, previous cardiovascular diseases and severe chronic kidney disease. Then, we have randomly assigned the patients to treatment with pravastatin 40 mg or a combined lipid-lowering nutraceutical (Armolipid Plus^®, containing monacolin 3 mg and berberine 500 mg).

RESULTS

After 8 weeks of treatment, 80% of pravastatin treated patients (N. 16/20) and 75% of those treated with Armolipid Plus^® (N. 15/20) reached the desired LDL-C target, while 50% of pravastatin treated patients (N. 10/20) and 80% of the Armolipid Plus^® treated ones reached the desired TG target (N. 16/20). No one adverse event has been registered during Armolipid Plus^®, while 1 patient claimed myalgia and 1 reported significant increase of CPK (> 3 ULN) during pravastatin treatment. Both patients were then treated with Armolipid Plus^® with resolution of symptoms and CPK increase, respectively.

CONCLUSION

In hypertriglyceridemic patients treated with fenofibrate, the association with a combined lipid lowering nutraceutical seem to be more effective in optimizing residual hypertriglyceridemia than pravastatin 40 mg, while being more tolerable and having similar effect on LDL-C plasma level.