The effects of silymarin supplementation on metabolic status and oxidative stress in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of clinical trials

Silybin restores glucose uptake after tumour necrosis factor-alpha and lipopolysaccharide stimulation in 3T3-L1 adipocytes

Obesity is associated with a low-grade chronic inflammatory process characterized by higher circulating TNFα levels, thus contributing to insulin resistance. This study evaluated the effect of silybin, the main bioactive component of silymarin, which has anti-inflammatory properties, on TNFα levels and its impact on glucose uptake in the adipocyte cell line 3T3-L1 challenged with two different inflammatory stimuli, TNFα or lipopolysaccharide (LPS). Silybin's pre-treatment effect was evaluated in adipocytes pre-incubated with silybin (30 or 80 µM) before challenging with the inflammatory stimuli (TNFα or LPS). For the post-treatment effect, the adipocytes were first challenged with the inflammatory stimuli and then post-treated with silybin. After treatments, TNFα production, glucose uptake, and GLUT4 protein expression were determined. Both inflammatory stimuli increased TNFα secretion, diminished GLUT4 expression, and significantly decreased glucose uptake. Silybin 30 µM only reduced TNFα secretion after the LPS challenge. Silybin 80 µM as post-treatment or pre-treatment decreased TNFα levels, improving glucose uptake. However, glucose uptake enhancement induced by silybin did not depend on GLUT4 protein expression. These results show that silybin importantly reduced TNFα levels and upregulates glucose uptake, independently of GLUT4 protein expression.

Effect of silymarin on lipid profile and glycemic control in patients with type 2 diabetes mellitus

This randomized clinical trial was conducted to evaluate the effects of silymarin supplementation on glycemic indices and serum lipid profile in type 2 diabetes mellitus (T2DM) patients. In this open-label randomized clinical trial study, 48 patients with T2DM were eligible to participate for 12 weeks and were divided into two groups randomly: 24 subjects in the intervention (received three 140 mg silymarin capsules daily and diet plan) and 24 in control (received a diet plan). Fasting blood samples and anthropometric data were collected, and glycemic indices and lipid profiles were determined at baseline and at the end of the study. Out of 60 patients included in the clinical trial, 48 people completed the study. In comparing silymarin and control groups before and after the study, a significant reduction was observed in weight and body mass index. However, after adjustment, no significant difference was seen between the two groups. Furthermore, daily consumption of three capsules of 140 mg silymarin for 12 weeks did not show any significant difference on the level of fasting blood sugar (p = 0.789), HbA1c (p = 0.719), and lipid profile. The findings of the present study show that silymarin did not lead to changes in the level of glycemic index and lipid profile in patients with T2DM.

Evaluation of the efficacy of silymarin and dexmedetomidine on kidney and lung tissue in the treatment of sepsis in rats with cecal perforation

Sepsis is a systemic inflammatory response syndrome that develops in the host against microorganisms. This response develops away from the primary infection site and results in end-organ damage. The present study aimed to investigate the protective and therapeutic effects on lung and kidney tissue of silymarin (S) and dexmedetomidine (DEX) applied 1 h before and after sepsis induced by the cecal ligation and puncture (CLP) method in rats. A total of 62 rats was randomly divided into eight groups: i) Control (n=6); ii) cecal perforation (CLP; n=8); iii) S + CLP (n=8; S + CLP; S administered 1 h before CPL); iv) CLP + S (n=8; S administered 1 h after CLP); v) DEX + CLP (n=8; D + CLP; DEX administered 1 h before CLP); vi) CLP + D (n=8; DEX administered 1 h after CLP); vii) SD + CLP (n=8; S and DEX administered 1 h before CLP) and viii) CLP + SD (n=8; S and DEX administered 1 h after CLP). After the cecum filled with stool, it was tied with 3/0 silk under the ileocecal valve and the anterior surface of the cecum was punctured twice with an 18-gauge needle. A total of 100 mg/kg silymarin and 100 µg/kg DEX were administered intraperitoneally to the treatment groups. Lung and kidney tissue samples were collected to evaluate biochemical and histopathological parameters. In the histopathological examination, all parameters indicating kidney injury; interstitial edema, peritubular capillary dilatation, vacuolization, ablation of tubular epithelium from the basement membrane, loss of brush border in the proximal tubule epithelium, cell swelling and nuclear defragmentation; were increased in the CLP compared with the control group. Silymarin administration increased kidney damage, including ablation of tubular epithelium from the basement membrane, compared with that in the CLP group. DEX significantly reduced kidney damage compared with the CLP and silymarin groups. The co-administration of DEX + silymarin decreased kidney damage, although it was not as effective as DEX-alone. To conclude, intraperitoneal DEX ameliorated injury in CLP rats. DEX + silymarin partially ameliorated injury but silymarin administration increased damage. As a result, silymarin has a negative effects with this dosage and DEX has a protective effect. In the present study, it was determined that using the two drugs together had a greater therapeutic effect than silymarin and no differences in the effects were not observed any when the application times of the agents were changed.

Effects of silymarin supplementation on liver and kidney functions: A systematic review and dose-response meta-analysis

It is suggested that supplementation with silymarin (SIL) has beneficial impacts on kidney and liver functions. This systematic review and dose-response meta-analysis assessed the impact of SIL administration on certain hepatic, renal, and oxidative stress markers. A systematic search was conducted in various databases to identify relevant trials published until January 2023. Randomized controlled trials (RCTs) that evaluated the effects of SIL on kidney and liver markers were included. A random-effects model was used for the analysis and 41 RCTs were included. The pooled results indicated that SIL supplementation led to a significant reduction in serum levels of alkaline phosphatase, alanine transaminase, creatinine, and aspartate aminotransferase, along with a substantial elevation in serum glutathione in the SIL-treated group compared to their untreated counterparts. In addition, there was a nonsignificant decrease in serum levels of gamma-glutamyl transferase, malondialdehyde (MDA), total bilirubin, albumin (Alb), total antioxidant capacity, and blood urea nitrogen. Sub-group analyses revealed a considerable decline in MDA and Alb serum values among SIL-treated participants with liver disease in trials with a longer duration (≥12 weeks). These findings suggest that SIL may ameliorate certain liver markers with potential hepatoprotective effects, specifically with long-term and high-dose supplementation. However, its nephroprotective effects and impact on oxidative stress markers were not observed. Additional high-quality RCTs with longer durations are required to determine the clinical efficacy of SIL supplementation on renal and oxidative stress markers.

The effects of silymarin consumption on inflammation and oxidative stress in adults: a systematic review and meta-analysis

BACKGROUND

Owing to the rich phytochemical content of Silymarin, it may effectively manage inflammation and oxidative stress. We, therefore, aimed to examine the existing evidence on the effect of Silymarin consumption on inflammation and oxidative stress factors by conducting a systematic review and meta-analysis of randomized controlled trials.

METHODS

A systematic literature search up to September 2023 was completed in PubMed/Medline, Scopus, and Web of Science, to identify eligible RCTs. Heterogeneity tests of the selected trials were performed using the I2 statistic. Random effects models were assessed based on the heterogeneity tests, and pooled data were determined as weighted mean differences with a 95% confidence interval.

RESULTS

Fifteen RCTs were included in this meta-analysis. Our findings showed that Silymarin consumption significantly decreased CRP (WMD, - 0.50 mg/L; 95% CI, (- 0.95 to - 0.04); p = 0.03), MDA (WMD, - 1.19 nmol/mL; 95% CI, (- 1.99 to - 0.38); p = 0.004), and IL-6 (WMD, - 0.44 pg/ml; 95% CI, (- 0.75 to - 0.12); p = 0.006). Silymarin consumption had no significant effects on IL-10, TAC, and GSH. A significant non-linear relationship was observed between the duration of the intervention and MDA changes.

CONCLUSIONS

Silymarin can help reduce inflammation in patients with diabetes and thalassemia by reducing MDA as an oxidative stress marker and CRP and IL-6 as inflammatory markers.

Impacts of Supplementation with Silymarin on Cardiovascular Risk Factors: A Systematic Review and Dose-Response Meta-Analysis

It has been suggested that silymarin (SIL) supplementation has positive effects on cardiovascular health and reduces the risk of cardiometabolic syndrome (CMS). This systematic review and dose-response meta-analysis assessed the impacts of SIL administration on cardiovascular risk factors. A systematic search of multiple databases was performed to identify eligible controlled trials published up to January 2023. The analysis used a random-effects model and included 33 trials with 1943 participants. It was revealed that SIL supplementation led to a notable reduction in serum levels of fasting blood glucose (FBG) (weighted mean difference (WMD): -21.68 mg/dL, 95% CI: -31.37, -11.99; p < 0.001), diastolic blood pressure (DBP) (WMD: -1.25 mmHg; 95% CI: -2.25, -0.26; p = 0.013), total cholesterol (TC) (WMD: -13.97 mg/dL, 95% CI: -23.09, -4.85; p = 0.003), triglycerides (TG) (WMD: -26.22 mg/dL, 95% CI: -40.32, -12.12; p < 0.001), fasting insulin (WMD: -3.76 mU/mL, 95% CI: -4.80, -2.72; p < 0.001), low-density lipoprotein (LDL) (WMD: -17.13 mg/dL, 95% CI: -25.63, -8.63; p < 0.001), and hemoglobin A1C (HbA1c) (WMD: -0.85%, 95% CI: -1.27, -0.43; p < 0.001) in the SIL-treated groups compared to their untreated counterparts. In addition, there were no substantial differences in body mass index (BMI), systolic blood pressure (SBP), C-reactive protein (CRP), body weight, and high-density lipoprotein (HDL) between the two groups. These outcomes suggest that SIL consumption reduces certain CMS risk factors and has favorable impacts on lipid and glycemic profiles with potential hypotensive effects. These findings should be supported by additional trials with larger sample sizes and longer durations.

Efficacy evaluation of Berberis aristata and Silybum marianum fixed dose combination on glycaemic and insulin resistance parameters in adult population: a systematic review and meta-analysis of randomized controlled trials

Background

Diabetes is one of the most prevalent metabolic diseases with high rate of morbidity and mortality. The increased level of blood glucose level and increased insulin resistance is the hallmark of diabetes. Currently, various non-pharmacological and pharmacological therapeutic options are used for lowering the glucose level and improving the insulin activity. The current systematic review and meta-analysis study was conducted to evaluate the efficacy of Berberis aristata and Silybum marianum fixed dose nutraceutical combination on serum glucose and glycated haemoglobin level and insulin resistance parameters.

Main Body

Randomized controlled trials, identified from three online databases, evaluating the efficacy of Berberis aristata and Silybum marianum fixed dose combination were identified and evaluated as per pre-defined protocol. Quality of studies was evaluated using PEDro scale, and risk of bias was assessed using Cochrane Risk of Bias Tool. Pooled effect was reported as mean difference (MD) and 95% confidence interval, while the complete study was conducted as per PRISMA and Cochrane guidelines. After complete literature screening and evaluation process, seven studies were included in the final analysis. Data of 825 participants (active group: 416 participants and control group: 409 participants) were utilized for the statistical analysis. All included studies (except one) were of good quality. Supplementation of fixed dose combination significantly reduced glucose level (MD: − 5.26 mg/dl; p = 0.02) and glycated haemoglobin (HbA1c) level (MD: − 0.69%; p < 0.0001) as compared to control therapy, while greater insulin resistance reduction was observed in active group and the difference approached significance (MD: − 0.64 HOMA-IR score; p = 0.08). Risk of bias analysis revealed some concerns regarding biasness (mainly due to randomization, outcome measurement and selected reporting biasness). All included studies had moderate risk of biasness. Sensitivity analysis revealed effect of particular study on overall heterogeneity observed, while neither significant publication bias nor any missing study was observed.

Conclusion

The results of current study suggest that B. aristata and S. marianum fixed dose combination is effective in improving glycaemic and insulin parameters and can be effective in diabetic population. The observed sensitivity of certain studies on overall heterogeneity and the moderate risk of biasness warrants further well-designed clinical studies to strengthen the results of current study.

Silymarin Reduced Insulin Resistance in Non-Diabetic Women with Obesity

Silymarin has ameliorated obesity, type 2 diabetes (T2DM), and insulin resistance (IR) in combination with standard therapy, diet, or exercise in recent studies. Obesity and IR are the main risk factors for developing T2DM and other metabolic disorders. Today, there is a need for new strategies to target IR in patients with these metabolic diseases. In the present longitudinal study, a group of non-diabetic insulin-resistant women with type 1 and type 2 obesity were given silymarin for 12 weeks, with no change in habitual diet and physical activity. We used the Homeostatic Model Assessment for Insulin Resistance Index (HOMA-IR) to determine IR at baseline and after silymarin treatment (t = 12 weeks). We obtained five timepoint oral glucose tolerance tests, and other biochemical and clinical parameters were analyzed before and after treatment. Treatment with silymarin alone significantly reduced mean fasting plasma glucose (FPG) and HOMA-IR levels at 12 weeks compared to baseline values (p < 0.05). Mean fasting plasma insulin (FPI), total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (Tg), indirect bilirubin, and C-reactive protein (CRP) levels decreased compared to baseline values, although changes were non-significant. The overall results suggest that silymarin may offer a therapeutic alternative to improve IR in non-diabetic individuals with obesity. Further clinical trials are needed in this type of patient to strengthen the results of this study.

Review and expert opinion on MAFLD, oxidative stress and multifunctional management

Metabolic-associated fatty-liver disease (MAFLD), previously known as non-alcoholic fatty liver disease, is the most widespread and emerging chronic liver disease worldwide, with increasing prevalence rates also in the Asia-Pacific region. The disease has a high socio-economic burden as it negatively impacts the finances and quality of life of individuals affected and has a major burden on healthcare systems. The most important pathological event in MAFLD aetiopathogenesis is oxidative stress, which leads to functional and structural abnormalities in the liver as well as being involved in the development of other concomitant cardiometabolic diseases. MAFLD is a rather complex multisystemic clinical condition involving liver damage and a wide spectrum of extrahepatic manifestations such as obesity, type 2 diabetes, metabolic syndrome and cardiovascular diseases. This complexity requires the cooperation of multiple experts to identify MAFLD at an early stage, treat associated comorbidities, and promptly refer the patient to the hepatologist when needed. This review summarizes the current knowledge about MAFLD and reports the opinion of a group of experts on the increasing prevalence and burden of the disease in the southeast Asia region, the current journey of patients with MAFLD in developing countries, the role of oxidative stress and antioxidant treatment, and the importance of a multidisciplinary approach for early diagnosis and disease management. This article is part of the Current clinical use of silymarin in the treatment of toxic liver diseases: a case series Special Issue: https://www.drugsincontext.com/special_issues/current-clinical-use-of-silymarin-in-the-treatment-of-toxic-liver-diseases-a-case-series.

Testosterone with Silymarin Improves Diabetes-obesity Comorbidity Complications by Modulating Inflammatory Responses and CYP7A1/ACC Gene Expressions in Rats

BACKGROUND

The co-morbidity of DMOB has become increasingly problematic among the world's population because of a high-calorie diet and sedentary lifestyle. DMOB is associated with lower testosterone (TN) levels, the male sex hormone. The phytochemical compound silymarin (SN) exerts antidiabetic activity by modifying β-cells and anti-obesity activity by inhibiting adipogenesis by methylxanthine.

AIM

The goal of this study was to find out how well testosterone (TN) with silymarin (SN) protects against oxidative stress and inflammation in the liver of the experimental rats with type 2 diabetes (T2D) and obesity (DMOB).

OBJECTIVES

The present study evaluates the efficacy of TN and SN combination (TNSN) on the levels of the potential parameters, such as body mass, serum marker enzymes, fasting glucose levels, HbA1c levels, lipid profile, enzymatic and non-enzymatic antioxidants, proinflammatory cytokines, gene expression pathways, and histopathology in a DMOB comorbidity rat model.

METHODS

Male Sprague-Dawley (SD) rats were fed a high-fat diet (HFD) for 20 weeks with an administration of a single dose of streptozotocin (STZ) i.p. injection (30 mg/kg) on the 9th week of the study. The procedure was to develop the DMOB co-morbidity model in the experimental animals. Co-treatment of TN and SN administration were followed throughout the experiment. Rats were sacrificed after overnight fasting to collect serum and liver tissue samples. Samples were analyzed using a clinical chemistry automated analyzer, spectrophotometry, and quantitative real-time PCR (qPCR) methods and protocols.

RESULTS

Analyses of body mass changes, serum marker enzymes, fasting glucose levels, HbA1c levels, lipid profiles, enzymatic and non-enzymatic antioxidants, TNF-α, IL-6, adiponectin, CYP7A1, ACC expression pathways, and histopathology showed significant abnormal levels (P ≤ 0.05) in the pathological group. These were efficiently treated to normal by the administration of TNSN.

CONCLUSION

These results concluded that TNSN exerted protective efficacy against the liver abnormalities in the co-morbidity of the DMOB rat model.

Effect of sesame (Sesamum indicum L.) consumption on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials

Conflicting evidence exists on the effect of sesame consumption on glucose metabolism in patients with type 2 diabetes (T2D). Therefore, this meta-analysis focuses on the relationship between sesame (Sesamum indicum L.) intervention and glycemic control in patients with T2D. Published literature was retrieved and screened from PubMed, Scopus, ISI Web of Science, and the Cochrane Library up to December 2022. Outcome measures included fasting blood sugar (FBS) concentrations, fasting insulin levels, and hemoglobin A1c (HbA1c) percentage. Pooled effect sizes were reported as weighted mean differences (WMDs) and 95% confidence intervals (CIs). Eight clinical trials (395 participants) were eligible for meta-analyses. Overall, sesame consumption significantly reduced serum FBS (WMD: -28.61 mg/dL, 95% CI: -36.07 to -21.16, p˂0.001; I2  = 98.3%) and HbA1c percentage (WMD: -0.99%, 95% CI: -1.22 to -0.76, p ≤ 0.001; I2  = 65.1%) in patients with T2D. However, sesame consumption did not significantly influence fasting insulin levels (Hedges's: 2.29, 95% CI: -0.06 to 4.63, p = 0.06; I2  = 98.1%). In summary, the current meta-analysis showed a promising effect of sesame consumption on glycemic control through reducing FBS and HbA1c, yet additional prospective studies are recommended, using higher doses and longer intervention period, to confirm the impact of sesame consumption on insulin levels in T2D patients.

The еffects of low mineral content water on microbiota, metabolic, and oxidative stress parameters in patients with type 2 diabetes mellitus

Although scientific evidence has shown that natural mineral waters have potential beneficial metabolic effects, there is still very scarce data on their influence on type 2 diabetes mellitus (T2DM). The study was designed to investigate the effects of low mineral water from the "Sneznik-1/79″ source in Serbia on microbiota, metabolic, and oxidative stress parameters in patients with T2DM. In total, 60 patients with confirmed T2DM were included in the study, and they consumed "Sneznik-1/79″ water for 28 days. To examine the positive effects of "Sneznik-1/79″ water, we compared the results before and after the four weeks of "Sneznik-1/79″ water intake. Standard biochemical analyses were carried out, such as glucose level, lipid profile, and stool tests. The blood samples were collected to evaluate the effects of "Sneznik-1/79″ water on the redox status. At the end of the monitoring period, the total cholesterol concentration significantly dropped compared to the initial value. A significant improvement in intestinal peristalsis was observed, which was reflected in the fact that after four weeks, all patients established regular, daily bowel movements. Moreover, consumption of "Sneznik-1/79″ water eliminated the appearance of dysbiosis in 50% of patients. Additionally, the antioxidant capacity was improved by increasing the concentration of superoxide dismutase and reduced glutathione. The result of our study pointed out that the intake of "Sneznik-1/79″ water could be a promising adjuvant therapy for improving intestinal peristalsis as well as reducing the appearance of dysbiosis in T2DM patients.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Effects of almond intake on oxidative stress parameters: A systematic review and meta-analysis of clinical trials

BACKGROUND AND AIMS

Several randomized controlled trials (RCTs) have shown that almonds can improve oxidative stress indices, but the results are controversial. Therefore, the goal of this research was to carry out a systematic review and meta-analysis of all RCTs that evaluated the effect of almonds on selected oxidative stress indices.

METHODS

A systematic search was conducted up to April 2022 on PubMed, Scopus, Web of Science, and Google Scholar. We have selected the studies that investigated the effects of almonds on malondialdehyde (MDA), and oxidized low-density lipoprotein (Ox-LDL) levels in adults. Data were pooled by using the random-effects model. The risk of bias in individual studies was assessed using the Cochrane Collaboration risk of bias tool.

RESULTS

Seven RCTs involving 424 participants were analyzed. The results indicated that almond intake led to a significant decrease in MDA levels (WMD: - 6.63 nmol/ml; 95 % CI: - 8.72 to - 4.54; P < 0.001). However, no significant effect was observed on Ox-LDL (Hedges' g: - 0.12; 95 % CI: - 0.34 to 0.10; P = 0.28). Sensitivity analysis showed that overall estimates were not affected by the elimination of any study. We did not observe any evidence regarding publication bias.

CONCLUSION

The present meta-analysis suggests that almond intake can improve MDA levels and might play a beneficial role in the reinforcement of the antioxidant defense system and amelioration of oxidative stress in adults. There is a need for more studies with larger groups to better estimate this effect.

A Comprehensive Review of the Cardiovascular Protective Properties of Silibinin/Silymarin: A New Kid on the Block

Silibinin/silymarin has been used in herbal medicine for thousands of years and it is well-known for its hepato-protective properties. The present comprehensive literature review aimed to critically summarize the pharmacological properties of silymarin extract and its main ingredient silibinin in relation to classical cardiovascular risk factors (e.g., diabetes mellitus, etc.). We also assessed their potential protective and/or therapeutic application in cardiovascular diseases (CVDs), based on experimental and clinical studies. Pre-clinical studies including in vitro tests or animal models have predominantly implicated the following effects of silymarin and its constituents: (1) antioxidant, (2) hypolipidemic, (3) hypoglycemic, (4) anti-hypertensive and (5) cardioprotective. On the other hand, a direct amelioration of atherosclerosis and endothelial dysfunction after silymarin administration seems weak based on scarce data. In clinical trials, the most important findings are improved (1) glycemic and (2) lipid profiles in patients with type 2 diabetes mellitus and/or hyperlipidemia, while (3) the anti-hypertensive effects of silibinin/silymarin seem very modest. Finally, the changes in clinical endpoints are not robust enough to draw a firm conclusion. There are significant limitations in clinical trial design, including the great variety in doses and cohorts, the underlying conditions, the small sample sizes, the short duration and the absence of pharmacokinetic/pharmacodynamic tests prior to study commitment. More data from well-designed and high-quality pre-clinical and clinical studies are required to firmly establish the clinical efficacy of silibinin/silymarin and its possible therapeutic application in cardiovascular diseases.

Silymarin from Milk Thistle Fruits Counteracts Selected Pathological Changes in the Lenses of Type 1 Diabetic Rats

Diabetes is a metabolic disease affecting many tissues and organs. The main etiological factor for diabetic complications is hyperglycemia and subsequent pathologies, such as oxidative stress. One of the organs susceptible to the development of diabetic complications is the eye with all of its elements, including the lens. The aim of this study was to evaluate the effect of silymarin, an extract obtained from milk thistle fruit husks, on the oxidative stress markers in the lenses of type 1 diabetic rats. The study was performed on male rats in which type 1 diabetes was induced with 60 mg/kg streptozotocin injection. Diabetic animals were treated via an intragastric tube with silymarin at 50 and 100 mg/kg doses for four weeks. Multiple oxidative stress and polyol pathway-related parameters were measured in the lenses, and auxiliary biochemical tests in the serum were conducted. Diabetes induced severe pathological changes both in the lenses and the serum, and silymarin counteracted several of them. Nevertheless, the qualitative analyses encompassing all tested parameters indicate that silymarin slightly improved the overall state of diabetic animals. Upon the obtained results, it can be concluded that silymarin reveals a faint positive effect on the lenses in type 1 diabetic rats.

The effects of Silymarin on the features of cardiometabolic syndrome in adults: A systematic review and meta-analysis

Some medicinal herbs and their effective components showed positive effects on the features of the cardiometabolic syndrome (CMS). The aim of the present systematic review and meta-analysis is to examine the effects of silymarin on the components of CMS in adults. Four electronic databases including PubMed/Medline, Scopus, Web of Science, and Embase were systematically searched up to December 31, 2020 to identify all eligible clinical trials. A random-effect model using DerSimonian and Laird method was used to estimate the pooled weighted mean differences (WMDs) and the 95% confidence intervals (95%CIs). Finally, 11 clinical trials met the eligibility criteria. Our results demonstrated that silymarin significantly reduced the levels of fasting blood glucose (WMD: -17.96 mg/dL, 95% CI: -32.91, -3.02;I² : 82.4%, p < 0.001), hemoglobin A1C (WMD: -1.25%, 95% CI: -2.34, 0.16; I² : 92.9%, p ˂ 0.001), total cholesterol (WMD: -17.46 mg/dL, 95% CI: -30.98, -3.95; I²  = 62.9%, p = 0.006), triglyceride (WMD: -25.70 mg/dL, 95% CI: -47.23, -4.17; I² :54.3%, p = 0.025), low-density lipoprotein-cholesterol (WMD: -10.53, 95% CI: -19.12, -1.94; I2: 37.5%, p = 0.119) and increased high-density lipoprotein- cholesterol (WMD: 3.36 mg/dL, 95% CI: 0.88, 5.84; I² : 37.4%, p = 0.120) compared to placebo. However, its effects on BMI were not statistically significant. Silymarin can be an effective complementary therapy to improve most features of CMS. However, due to high heterogeneity and limited clinical trials in some parameters, further high-quality clinical trials are needed to confirm its efficacy.

A comprehensive review on phytochemicals for fatty liver: are they potential adjuvants?

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of metabolic syndrome and, as such, is associated with obesity. With the current and growing epidemic of obesity, NAFLD is already considered the most common liver disease in the world. Currently, there is no official treatment for the disease besides weight loss. Although there are a few synthetic drugs currently being studied, there is also an abundance of herbal products that could also be used for treatment. With the World Health Organization (WHO) traditional medicine strategy (2014-2023) in mind, this review aims to analyze the mechanisms of action of some of these herbal products, as well as evaluate toxicity and herb-drug interactions available in literature.

The effect of almond intake on glycemic control: A systematic review and dose-response meta-analysis of randomized controlled trials

Number trials have evaluated the effect of almond intake on glycemic control in adults; however, the results remain equivocal. Therefore, the present meta-analysis aims to examine the effectiveness of almond intake on glycemic parameters. Online databases including PubMed, Scopus, ISI web of science, Embase, and Cochrane Library were searched up to August 2021 for trials that examined the effect of almond intake on glycemic control parameters including fasting blood sugar (FBS), insulin, HOMA-IR, and HbA1C. Treatment effects were expressed as mean difference (MD) and the standard deviation (SD) of outcomes. To estimate the overall effect of almond intake, we used the random-effects model. In total, 24 studies with 31 arms were included in our analysis. The meta-analysis revealed that almond intake did not significantly change the concentrations of FBS, HbA1c, insulin levels, and HOMA-IR. In conclusion, there is currently no convincing evidence that almonds have a clear beneficial effect on glycemic control. Future studies are needed before any confirmed conclusion could be drowned.

Nano-based drug delivery systems used as vehicles to enhance polyphenols therapeutic effect for diabetes mellitus treatment

Diabetes mellitus is one of the biggest health emergencies of the 21^st century worldwide, characterized by deficiency in insulin secretion and/or action, leading to hyperglycemia. Despite the currently available antidiabetic therapeutic options, 4.2 million people died in 2019 due to diabetes. Thus, new effective interventions are required. Polyphenols are plant secondary metabolites and have been recognized for their vast number of biological activities, including potential antidiabetic effects. However, the poor bioavailability and high metabolization of polyphenols restrict their biological effects in vivo. Nanotechnology is a promising area of research to improve the therapeutic effect of several compounds. Therefore, this review provides an overview of the literature about the utility of nano-based drug delivery systems as vehicles of polyphenols in diabetes treatment. It was possible to conclude that, in general, nano-based drug delivery systems can potentiate the beneficial antidiabetic properties of polyphenols, when compared with the free compounds, opening a new field of research in diabetology.

Effects of grape products on inflammation and oxidative stress: A systematic review and meta-analysis of randomized controlled trials

This systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted to determine the effects of grapes and grape products on inflammation and oxidative stress among adults. PubMed, Scopus, ISI Web of Science, and Cochrane Library databases were searched up to July 2020 to identify RCTs investigating the effects of grape and grape products on inflammatory and oxidative stress markers. Weighted mean differences (WMD) were pooled using a random-effects model. Of the 8,962 identified studies, 24 RCTs (27 arms) were included in the statistical analysis. Grape products significantly reduced serum C-reactive protein (CRP) levels (WMD: -0.35 mg/L; 95% CI: -0.62, -0.09, p = .008), but they had no significant effect on serum tumor necrosis factor-alpha (TNF-α) (WMD = -1.08 pg/ml; 95% CI: -2.29, 0.11, p = .07), interleukin-6 (IL-6) (WMD = 0.13 pg/ml; 95% CI: -0.35, 0.60, p = .60), total antioxidant capacity (TAC) (WMD = 0.15; 95% CI: -0.35, 0.65, p = .54), or malondialdehyde (MDA) (WMD = 0.14; 95% CI: -0.64, 0.92, p = .72). The analysis indicated possible decreasing effects of grapes and grape products on CRP, but they might not be able to change IL-6, TNF-α, TAC, and MDA concentrations. Nonetheless, further studies are warranted before definitive conclusions may be reached.

The effect of grapes/grape products on glycemic response: A systematic review and meta-analysis of randomized controlled trials

The aim of this study was to perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to examine the effect of grapes/grape products supplementation on glycemic indices in adults. Our systematic search to find relevant RCTs was performed up to February 2020 using PubMed, Scopus, ISI Web of Science, Cochrane Library, and Google Scholar. Based on the heterogeneity between included studies, a random effects or a fixed model was applied in the meta-analysis, and results were expressed as weighted mean differences (WMD) with 95% confidence intervals (CI). Twenty-nine clinical trials (1,297 participants) fulfilled the eligibility criteria of the present meta-analysis. Overall, the grapes/grape products supplementation significantly reduced homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: -0.54, 95% CI: -0.91, -0.17, p = . 004) but did not affect fasting insulin levels (WMD: -0.90 μIU/ml, 95% CI: -1.04, 2.84, p = .362) and hemoglobin A1C (Hb1Ac) percentage (WMD: 0.00%, 95% CI: -0.10, 0.11, p = . 916) in the main analyses. In addition, changes to fasting blood glucose (FBG) levels were in favor of the control group (WMD: 1.19 mg/dl, 95% CI: 0.05, 2.34, p = .041). We found that giving grapes/grape products to adults might have beneficial effects on the HOMA-IR. Further, large-scale RCTs with longer duration are required to confirm these results.

The effect of spirulina on type 2 diabetes: a systematic review and meta-analysis

Purpose

The aim of the present study was to investigate the effect of spirulina on lipid profiles and glycemic related markers in type 2 diabetes patients.

Methods

PubMed, Scopus, Cochrane Library, ISI Web of Science, and Google Scholar were searched from inception to August 2020. All clinical trials which investigated the effect of spirulina supplementation on glycemic related markers and lipid profile among type 2 diabetes patients were included. Random effects modeling was utilized for pooling analysis to compensate for the between-study heterogeneity.

Results

Eight studies (9 arms) were included in the meta-analysis. We found a significant reduction in fasting blood glucose (-17.88 mg/dl; 95% CI: -26.99, -8.78; I ² : 25%), triglyceride (-30.99 mg/dl; 95% CI: -45.20, -16.77; I ² : 50%), total-cholesterol (-18.47 mg/dl; 95% CI: -33.54, -3.39; I ² : 73%), LDL-C (-20.04 mg/dl; 95% CI: -34.06, -6.02; I ² : 75%), VLDL (-6.96 mg/dl; 95% CI: -9.71, -4.22; I ² : 33%), in addition to a significant increase in HDL-C (-6.96 mg/dl; 95% CI: -9.71, -4.22; I ² : 33%), after spirulina administration. No significant effect was observed on HbA1C or post prandial blood sugar following spirulina consumption.

Conclusion

The present study suggests that spirulina supplementation can elicit beneficial effects on fasting blood glucose and blood lipid profiles.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-021-00760-z.

The therapeutic effects of silymarin for patients with glucose/lipid metabolic dysfunction: A meta-analysis

BACKGROUND

To comprehensively evaluate the treatment efficacy and safety of silymarin for patients with glucose/lipid metabolic dysfunction using a meta-analysis.

METHODS

A systematic literature search in PubMed, EMBASE and Cochrane Library databases was performed up to October 1, 2019. STATA 13.0 software was used to estimate pooled standardized mean difference (SMD) and 95% confidence interval (95% CI).

RESULTS

Sixteen studies involving 1358 patients were identified. Overall meta-analysis showed that compared with control, silymarin significantly reduced levels of fasting blood glucose (SMD: -1.27, 95% CI = [-1.78, -0.76]; P < .001), homeostatic model assessment for insulin resistance (SMD: -0.41, 95% CI = [-0.70, -0.12]; P = .005), hemoglobin A1c (SMD: -1.88, 95% CI = [-2.57, -1.20]; P < .001), total cholesterol (SMD: -1.13, 95% CI = [-1.82, -0.77]; P < .001), triglyceride (SMD: -0.37, 95% CI = [-0.69, -0.05]; P = .025), low-density lipoprotein-cholesterol (SMD: -1.30, 95% CI = [-1.93, -0.67]; P < .001), C-reactive protein (SMD: -0.63, 95% CI = [-1.01, -0.27]; P = .001), and increased high-density lipoprotein-cholesterol (SMD: 0.17, 95% CI = [0.05, 0.29]; P = .005), but had no impacts on function indicators of liver and kidney (alanine transaminase, aspartate aminotransferase, creatinine phosphokinase, creatinine) and the complication rate. Subgroup analyses indicated that insulin (which was negative in overall analysis) was significantly decreased in patients undergoing silymarin monotherapy (SMD: -2.03, 95% CI = [-3.03, -1.04]; P = .044) for more than 3 months (SMD: -0.01, 95% CI = [-0.25, -0.24]; P = .035).

CONCLUSION

Supplementation of silymarin may be effective and safe for the management of diabetes mellitus and hyperlipidemia.

Silymarin: not just another antioxidant

Silymarin (Silybum marianum; SM), popularly known as milk thistle, is an extract that has been used for many centuries to treat liver diseases. In recent years, several studies have shown that SM is not only just another antioxidant but also a multifunctional compound that exhibits several beneficial properties for use in the treatment and prevention of different types of pathologies and disorders. This review aims at demonstrating the main protective activities of SM in diseases, such as cancer, diabetes, hepatitis, non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis C virus, hepatitis B virus, metabolic syndrome, depression, cardiovascular diseases and thalassemia, in addition to its photoprotective activity in in vitro tests and preclinical studies. Its main functions include antioxidant and anti-inflammatory effects, and it acts as modulator of signaling pathways. It has been suggested that SM presents great multifunctional potential and is capable of achieving promising results in different types of research. However, caution is still needed regarding its indiscriminate use in humans as there are only a few clinical studies relating to the adequate dose and the actual efficacy of this extract in different types of diseases.

Nanostructured lipid carriers for oral delivery of silymarin: Improving its absorption and in vivo efficacy in type 2 diabetes and metabolic syndrome model

Silymarin (SLM) is a mixture of flavonolignans extracted from the fruit of Silybum marianum L. Gaertn. which has been used for decades as a hepatoprotector. Silymarin has recently been proposed to be beneficial in type 2 diabetic patients. Constituents of SLM are poorly water-soluble and low permeable compounds, with consequently limited oral bioavailability. This study aimed to investigate the possibility of delivery of SLM via nanostructured lipid carriers (NLCs) to overcome these issues and for preparation of an oral dosage form. NLCs were prepared through an emulsion/evaporation/solidifying method. Cetyl palmitate:Lauroglycol 90 was selected as the lipid mixture and Brij S20 as surfactant. NLCs were chemically and physically characterized. Encapsulation efficiency was more than 92%. The storage stability of the NLC suspension was also investigated and the freeze-drying process was taken into consideration. After assessing the stability of the formulation in a simulated gastrointestinal environment, the release of SLM was monitored in different pH conditions. In vitro experiments with artificial membranes (PAMPA) and Caco-2 cells revealed that the NLCs enhanced the permeation of SLM. Active processes are involved in the internalization of NLCs, as evidenced by cellular uptake studies. After preliminary toxicological studies, the formulation was studied in vivo in a streptozotocin (STZ)-induced diabetic mouse model in the presence of metabolic syndrome. The formulation was also compared to an NLC containing stearic acid:Capryol 90, to evaluate the effect of the lipid matrix on the in vivo performance of nanocarriers. Finally, hepatic histopathological analyses were also conducted. Both SLM-loaded NLCs exhibited in vivo a significant down-regulation of blood glucose and triglyceride levels better than free SLM, with a liver-protective effect. Furthermore, both formulations showed a significant anti-hyperalgesic effect on STZ-induced neuropathy.

The association between omentin and diabetes: a systematic review and meta-analysis of observational studies

AIMS

A number of studies have examined the association between the serum levels of omentin and diabetes, but the findings have been inconclusive. Herein, we systematically reviewed available observational studies to elucidate the overall relationship between omentin and diabetes, including type 1 diabetes mellitus (T1DM), type 2 diabetes mellitus (T2DM), and impaired glucose tolerance (IGT) among adolescent and adult population.

METHODS

PubMed, Cochrane's Library, Science Direct, Scopus, Google Scholar, and ISI Web of Science databases were searched for all available literature until January 2019 for studies assessing the association between omentin and diabetes. The Newcastle-Ottawa Quality Assessment Scale was used to assess the quality of each study.

RESULTS

A total of 28 articles met the inclusion criteria and were included in our systematic review and meta-analysis. There was a significant association between serum omentin and diabetes (WMD-1.68; 95% CI, -2.17 to -1.19; P<0.001). The result of our sub-group analysis based on participants' health status revealed that omentin was significantly lower in T2DM and IGT subjects but not in T1DM ones compared to healthy controls.

CONCLUSION

We found that serum omentin level is significantly lower in T2DM and IGT patients but not in T1DM ones. These data could be used by clinicians for early diagnosis and management of diabetes. Furthermore, we need more clinical trials to investigate new agents which could influence omentin levels.