Mulberry-extract improves glucose tolerance and decreases insulin concentrations in normoglycaemic adults: Results of a randomised double-blind placebo-controlled study

Combined Mulberry Leaf Polysaccharide-Caged Liposomes for Effective Oral Drug Delivery in Rat Model

Introduction

Mulberry leaf polysaccharide (MLP) has gained attention as a potential anti-diabetic agent for lowering blood glucose and improving insulin sensitivity. However, the low gastrointestinal stability and oral bioavailability limit its clinical application. To address this issue, a novel drug-caged liposomes (MLP-CL) was developed to enhance oral delivery efficiency of MLP compared to conventional drug-encapsulated liposomes (MLP-L).

Methods

MLP-L and MLP-CL were prepared by the thin-film hydration method. Subsequently, the structural integrity of these liposomes was assessed via in vitro release test and confocal laser microscopy (CLSM) analysis. Madin-Darby canine kidney (MDCK) cells were employed to investigate the cellular uptake mechanisms and transcellular transport efficiency. Finally, the biodistribution profiles and transport mechanisms of liposomes were evaluated through in vivo fluorescence imaging and pharmacokinetic studies in Sprague Dawley rats.

Results

Compared to MLP-L, which released 80% of MLP within 4 hours, MLP-CL showed sustained release with only 40% released in the same period. MLP-CL also enabled more effective co-delivery of MLP and liposomes to MDCK cells, indicating improved structural integrity and cellular uptake. Transcellular transport assay confirmed that MLP-CL was transported across cells more efficiently. In vivo, MLP-CL increased intestinal accumulation and raised plasma MLP concentration by 50%. Additionally, by comparing the discrepancy between the lymphatic-suppression model and the normal model, it was found that 63.56% of MLP-CL was absorbed through the lymphatic pathway compared to 18.05% for MLP-L.

Conclusion

Compared to conventional MLP-L, conjugation of polysaccharide improves the structural integrity of MLP-CL in the gastrointestinal tract, which in turn improves lymphatic uptake and bioavailability. This provides an effective strategy for the design of polysaccharide delivery systems.

Nutraceutical Properties of Thai Mulberry (Morus alba L.) and Their Effects on Metabolic and Cardiovascular Risk Factors in Individuals with Obesity: A Randomized, Single-Blind Crossover Trial

Background/Objectives: Mulberries exhibit antioxidant properties that may attenuate metabolic abnormalities. Kamphaeng Saen mulberry (KPS-MB-42-1) contains anthocyanins, polyphenols, and nutrients, but few studies have explored its benefits for human health. This study investigated the effects of a concentrated mulberry drink (CMD) from the KPS-MB-42-1 cultivar on metabolic and cardiovascular risk factors in obese individuals. Methods: A single-blind, randomized crossover clinical pilot trial was performed on individuals with obesity. Participants consumed 100 g of CMD daily, alternating with placebo for 6 weeks. Body composition, blood pressure, and blood samples were assessed at baseline and post-intervention. Results: This study was completed with 12 participants (7 men, 5 women, aged 30-55 years, BMI 32.1 ± 5.98 kg/m2) consuming CMD with 1041.90 mg total phenolic compounds and 35.34 mg total anthocyanins. No significant changes in body composition were observed. CMD consumption significantly reduced systolic and diastolic blood pressure, and mean arterial pressure, compared to baseline and placebo periods (p < 0.05). While total cholesterol, LDL-C, and HDL-C remained unchanged, triglycerides were significantly lower during CMD consumption compared to placebo periods (p < 0.05). Fasting plasma glucose (FPG) levels were stable during CMD consumption but increased significantly with the placebo period (p < 0.05). C-reactive protein levels were also significantly lower during CMD consumption compared to placebo periods (p < 0.05). No changes in blood coagulation indicators (prothrombin time, activated partial thromboplastin time, and the international normalized ratio) were found. Conclusions: CMD improved metabolic markers, particularly regarding its antihypertensive effects. These findings highlight CMD's potential as a health drink for managing metabolic syndrome and preventing chronic diseases.

Morus alba: natural and valuable effects in weight loss management

Overweight and obesity are conditions associated with serious comorbidities, such as diabetes and cardiovascular disease. Prevalence of excessive fat accumulation is increasing worldwide, and thus the need for efficient and sustainable weight loss regimes has become a major issue in clinical practice. Despite the important advances in the development of anti-obesity medications (AOM), their side effects, cost, and accessibility, are limiting factors for their routine use. Conversely, the studies of medicinal plants for weight management holds strong promise as a growing area of research. This review consolidates the representative evidence about the beneficial impacts of Morus alba on weight management and associated metabolic parameters, encompassing: inhibition of digestive enzymes, and thus contribution to the energy deficit required for weight loss, improvements in glucose and lipid metabolism, and attenuation of adiposity. Findings from in vitro, in vivo, and clinical investigations reviewed in the paper, demonstrate that white mulberry extracts have the potency to supplement efficiently and safely a healthy weight management approach.

Suppression of the postprandial hyperglycemia in patients with type 2 diabetes by a raw medicinal herb powder is weakened when consumed in ordinary hard gelatin capsules: A randomized crossover clinical trial

INTRODUCTION

Contradictory claims about the efficacy of several medicinal plants to promote glycemic control in patients with type 2 diabetes mellitus (T2DM) have been explained by divergences in the administration form and by extrapolation of data obtained from healthy individuals. It is not known whether the antidiabetic effects of traditional herbal medicines are influenced by gelatin capsules. This randomized crossover trial aimed to evaluate the acute effect of a single dose of raw cinnamon consumed orally either dissolved in water as a beverage or as ordinary hard gelatin capsules on postprandial hyperglycemia (>140 mg/dL; >7.8 mmol/L) in T2DM patients elicited by a nutritionally-balanced meal providing 50 g of complex carbohydrates.

METHODS

Fasting T2DM patients (n = 19) randomly ingested a standardized meal in five experimental sessions, one alone (Control) and the other after prior intake of 3 or 6 g of crude cinnamon in the form of hard gelatin capsules or powder dissolved in water. Blood glucose was measured at fasting and at 0.25, 0.5, 0.75, 1, 1.5 and 2 hours postprandially. After each breakfast, its palatability scores for visual appeal, smell and pleasantness of taste were assessed, as well as the taste intensity sweetness, saltiness, bitterness, sourness and creaminess.

RESULTS

The intake of raw cinnamon dissolved in water, independently of the dose, decreased the meal-induced large glucose spike (peak-rise of +87 mg/dL and Δ1-hour glycemia of +79 mg/dL) and the hyperglycemic blood glucose peak. When cinnamon was taken as capsules, these anti-hyperglycemic effects were lost or significantly diminished. Raw cinnamon intake did not change time-to-peak or the 2-h post-meal glycaemia, but flattened the glycemic curve (lower iAUC) without changing the shape that is typical of T2DM patients.

CONCLUSIONS

This cinnamon's antihyperglycemic action confirms its acarbose-like property to inhibit the activities of the carbohydrate-digesting enzymes α-amylases/α-glucosidases, which is in accordance with its exceptionally high content of raw insoluble fiber. The efficacy of using raw cinnamon as a diabetes treatment strategy seems to require its intake at a specific time before/concomitantly the main hyperglycemic daily meals. Trial registration: Registro Brasileiro de Ensaios Clínicos (ReBEC), number RBR-98tx28b.

A 90-day preclinical toxicological evaluation in rats of a highly purified and concentrated mulberry leaf extract

Mulberry (genus Morus) leaves have long been used as a human food, especially in Asia, and animal feed. More recently, mulberry leaf extracts have been introduced as a convenient way to consume mulberry for non-nutritional functional effects. Reducose® 5% is an Morus alba leaf extract that has been highly purified and standardized to a content of 5 ± 0.5% 1-deoxynojirimycin, a naturally present polyhydroxylated piperidine alkaloid analog of D-glucose. This extract has previously been evaluated in acute and subacute (28-day) oral toxicity studies in which no adverse effects of the test item were observed in mice or rats, respectively. Due to continued and growing interest in the extract in multinational markets, we have now further investigated potential toxic effects in subchronic (90-day) oral toxicity study in male and female Han:WIST rats. The test item was administered at doses of 850, 1700, and 2550 mg/kg bw/day, and did not cause adverse effects in clinical signs, body weight development, clinical pathology, gross pathology, or histopathology in comparison to the vehicle-control group. The no-observed-adverse-effect-level was determined to be 2550 mg/kg bw/day. These results add to the existing body of both preclinical and clinical work relevant to the safety of the extract and of interest to regulators in various global markets.

A Novel Nutraceutical Supplement Lowers Postprandial Glucose and Insulin Levels upon a Carbohydrate-Rich Meal or Sucrose Drink Intake in Healthy Individuals-A Randomized, Placebo-Controlled, Crossover Feeding Study

BACKGROUND

Alkaloid- and polyphenol-rich white mulberry leaf and apple peel extracts have been shown to have potential glucose-lowering effects, benefitting the control of postprandial blood glucose levels. This study aimed to determine the effect of the combination of Malus domestica peel and Morus alba leaf extracts (GLUBLOCTM) on postprandial blood glucose and insulin-lowering effects in healthy adults after a carbohydrate-rich meal or sucrose drink intake.

METHODS

This study was designed as a randomized, crossover, single-blinded clinical trial. Out of 116 healthy participants, 85 subjects (aged 18-60 years) completed the day 1 and 5 crossover study. On day 1, subjects were supplemented with a placebo or GLUBLOCTM tablet 10 min before the carbohydrate-rich meal (300 g of tomato rice) or sucrose drink intake (75 g of sucrose dissolved in 300 mL water). On day 5, the treatments were crossed over, and the same diet was followed. Postprandial blood glucose and insulin levels were measured on days 1 and 5 (baseline 0, post-meal 30, 60, 90, and 120 min). Differences in iAUC, Cmax, and Tmax were determined between the placebo and GLUBLOCTM-treated cohorts.

RESULTS

Significant changes in total iAUC (0-120 min), Cmax, and Tmax of postprandial blood glucose and insulin levels were noticed upon GLUBLOCTM supplementation. The percentage reduction in the iAUC of blood glucose levels was 49.78% (iAUC0-60min) and 43.36% (iAUC0-120min), respectively, compared with the placebo in the sucrose drink intake study. Similarly, there was a 41.13% (iAUC0-60min) and 20.26% (iAUC0-120min) glucose-lowering effect compared with the placebo in the carbohydrate-rich meal intake study.

CONCLUSIONS

Premeal supplementation with GLUBLOCTM significantly reduced the postprandial surge in blood glucose and insulin levels after a carbohydrate-rich meal or sucrose drink intake over 120 min in healthy individuals. This study proves that GLUBLOCTM can manage steady postprandial blood glucose levels.

1-DNJ Alleviates Obesity-Induced Testicular Inflammation in Mice Model by Inhibiting IKKβ/ NF-kB Pathway

Obesity is associated with chronic inflammation that affects various organs in the body, including the reproductive system, which is a key factor in male infertility. 1-Deoxynojirimycin (1-DNJ) is a natural alkaloid in mulberry leaves, which has anti-inflammatory capabilities, yet, it's effects on obesity-induced inflammation-related male infertility remain unclear. Therefore, this research investigates the underlying mechanism by which 1-DNJ may mitigate fertility impairment in male mice caused by obesity-related inflammation. Male mice with high-fat diet (HFD)-induced obesity were treated with 1-DNJ or metformin for 8 weeks. Metabolic profiles were evaluated by enzyme method. Reproductive capacity was assessed by sperm viability, motility and counts, immunohistochemistry was performed to evaluate the testicular damage caused by obesity and inflammation. The inflammation was assessed by measuring the levels of tumor necrosis factor α (TNFα), interleukin 1β (IL-1β), and interleukin 6 (IL-6). The activation of IκB kinase β (IKKβ) and nuclear factor κB (NF-κB) was examined using western blot and immunohistochemistry. HFD induced obesity in mice with obvious lipid metabolism disorder. The obese male mice had a decreased testosterone level, impaired sperm motility, and increased inflammatory factors. 1-DNJ treatment improved the testosterone level in the obese mice, ameliorated the testicular structure damage and improve sperm viability. In addition, 1-DNJ treatment inhibited IKKβ/NF-kB signaling pathway and reduced inflammation in obese mice. 1-DNJ can improve the fertility of obese men by reducing obesity as well as obesity-induced inflammation. These findings provide new insights for 1-DNJ to alleviate inflammation caused by obesity and provide future possibilities for treating male infertility.

Understanding the Impact of Different Doses of Reducose® Mulberry Leaf Extract on Blood Glucose and Insulin Responses after Eating a Complex Meal: Results from a Double-Blind, Randomised, Crossover Trial

Non-communicable diseases (NCDs) are becoming an increasingly important health concern due to a rapidly ageing global population. The fastest growing NCD, type 2 diabetes mellitus (T2DM), is responsible for over 2 million deaths annually. Lifestyle changes, including dietary changes to low glycemic response (GR) foods, have been shown to reduce the risk of developing T2DM. The aim of this study was to investigate whether three different doses of Reducose®, a mulberry leaf extract, could lower the GR and insulinemic responses (IR) to a full meal challenge in healthy individuals. A double-blind, randomised, placebo-controlled, repeat-measure, crossover design trial was conducted by the Oxford Brookes Centre for Nutrition and Health; 37 healthy individuals completed the study. Participants consumed capsules containing either 200 mg, 225 mg, 250 mg Reducose® or placebo before a test meal consisting of 150 g white bread and egg mayo filler. Capillary blood samples were collected at 15-min intervals in the first hour and at 30-min intervals over the second and third hours to determine glucose and plasma insulin levels. The consumption of all three doses of Reducose® resulted in significantly lower blood glucose and plasma insulin levels compared to placebo. All three doses of Reducose® (200 mg, 225 mg, 250 mg) significantly lowered glucose iAUC 120 by 30% (p = 0.003), 33% (p = 0.001) and 32% (p = 0.002), respectively, compared with placebo. All three doses of Reducose® (200 mg, 225 mg, 250 mg) significantly lowered the plasma insulin iAUC 120 by 31% (p = 0.024), 34% (p = 0.004) and 38% (p < 0.001), respectively. The study demonstrates that the recommended dose (250 mg) and two lower doses (200 mg, 225 mg) of Reducose® can be used to help lower the GR and IR of a full meal containing carbohydrates, fats and proteins.

Glucose-lowering effect of Reducose® enriched with 1-deoxynojirimycin and l-leucine: Studies on insulin secretion in INS-1 cells and reduction of blood glucose in diabetic rats

The extract of mulberry leaf and its active ingredients have already been reported to have anti-diabetic effects; however, further studies are required to obtain better quality extracts and higher yields of active ingredients. Reducose® is a commercially available aqueous extract of mulberry leaves with a high content of active ingredients. In this study, the biological activities of Reducose®, 1-deoxynojirimycin, and l-leucine were evaluated using a glucose-stimulated insulin secretion (GSIS) assay. The GSIS assay results were expressed as the glucose-stimulated index (GSI). Considering the pharmacological safety in pancreatic β-cells, the appropriate non-toxic concentrations were selected by screening for cytotoxicity of Reducose®, 1-deoxynojirimycin, and l-leucine before the GSIS assay. The effect of Reducose®, 1-deoxynojirimycin, and l-leucine on glucose-stimulated insulin secretion in INS-1 cells was compared. Reducose®, 1-deoxynojirimycin, and l-leucine increased the GSI values more effectively than gliclazide (positive control). This was associated with an increase in protein expression, such as peroxisome proliferator-activated receptor-γ, insulin receptor substrate-2, activated pancreatic and duodenal homeobox-1, which are related to the regulation of pancreatic β-cell function and survival. In order to elucidate the effect of Reducose® in anti-diabetic effects, blood glucose levels, insulin levels, and liver and lipid concentrations were investigated in a Sprague-Dawley rat model of high-fat diet/streptozotocin-induced diabetes. We observed that administration of Reducose® can decrease fasting blood glucose levels and reduce the production of AST, ALT, TG, and TC to a similar extent as metformin (positive control). These results suggested that Reducose® play a role in promoting GSIS but not enough to show that the content and proportion of 1-deoxynojirimycin and l-leucine play an important role in the GSIS activity of Reducose®.

Effect of mulberry fruit extract on post-prandial glycaemic and insulinemic responses to different rice types: a randomised trial in healthy adults

We previously reported that the addition of a specified mulberry fruit extract (MFE) to rice consistently reduces post-prandial glycaemic (PPG) and post-prandial insulinemic (PPI) responses. This research tested whether this effect generalises to a broad range of rice types, reflecting the wide variation in rice characteristics known to influence glycaemic responses. In a randomised, balanced, partial factorial crossover design, Sona Masoori (SM), Bora Saul (BS), Gobindobogh (Gb) and Banskati (Bn) rices were tested with and without 0·37 g MFE. Healthy, normal-weight Indian adults (N 120) each consumed four of the eight possible boiled rice meals, all containing about 50 g available carbohydrate. The primary outcome was the effect of MFE on PPG, expressed as the percentage change in the positive, incremental AUC over 2 h. The mean effect of MFE on PPG for all rice types combined was -11·4 % (P < 0·003). The reduction in PPG was in a qualitatively similar range for all rice types (-9·8 to -15·1 %), and this was statistically significant for Bn. MFE also reduced the corresponding PPI response to all rice types combined by a mean of 10·1 % (P < 0·001; range -6·1 to -13·4 %), and the reduction in PPI was statistically significant for SM, Gb and BS. In conclusion, addition of 0·37 g MFE modestly reduced PPG and PPI responses to rices in general, and the effects were statistically significant for specific rice types.

Mulberry leaf extract and neochlorogenic acid ameliorate glucolipotoxicity-induced diabetic nephropathy in high-fat diet-fed db/db mice

Diabetic nephropathy, a major diabetes complication, is often exacerbated by glucolipotoxicity. The potential benefits of mulberry leaf extract (MLE) and its primary component, neochlorogenic acid (nCGA), in combating this condition have not been extensively explored. High-fat diet-fed db/db mice were employed as a model for glucolipotoxicity-induced diabetic nephropathy. The mice were treated with MLE or nCGA, and their body weight, insulin sensitivity, blood lipid profiles, and kidney function were assessed. In addition, modulation of the JAK-STAT, pAKT, Ras, and NF-κB signaling pathways by MLE and nCGA was evaluated. MLE and nCGA did not significantly decrease blood glucose level but effectively mitigated the adverse effects of a high-fat diet on blood lipid profile and kidney function. Improvements in body weight, insulin sensitivity, and kidney structure, along with a reduction in fibrosis, were observed. Both MLE and nCGA regulated lipid metabolism abnormalities, significantly inhibited the accumulation of glycosylated substances in glomeruli, and modulated crucial signaling pathways involved in diabetic nephropathy. Although they do not directly affect blood glucose level, MLE and nCGA show significant potential in managing glucolipotoxicity-induced diabetic nephropathy by targeting lipid metabolism and key molecular pathways. The present findings suggest MLE and nCGA may be promising therapeutic agents for diabetic nephropathy, and further exploration in human patients is warranted.

A Basic Study of the Effects of Mulberry Leaf Administration to Healthy C57BL/6 Mice on Gut Microbiota and Metabolites

Mulberry leaves contain α-glucosidase inhibitors, which have hypoglycemic effects and are considered functional foods. However, few reports have covered the effects of mulberry leaf components on normal gut microbiota and gut metabolites. Herein, gut microbiota analysis and NMR-based metabolomics were performed on the feces of mulberry leaf powder (MLP)-treated mice to determine the effects of long-term MLP consumption. Gut microbiota in the mouse were analyzed using 16S-rRNA gene sequencing, and no significant differences were revealed in the diversity and community structure of the gut microbiota in the C57BL/6 mice with or without MLP supplementation. Thirty-nine metabolites were identified via 1H-NMR analysis, and carbohydrates and amino acids were significantly (p < 0.01-0.05) altered upon MLP treatment. In the MLP-treated group, there was a marked increase and decrease in maltose and glucose concentrations, respectively, possibly due to the degradation inhibitory activity of oligosaccharides. After 5 weeks, all amino acid concentrations decreased. Furthermore, despite clear fluctuations in fecal saccharide concentrations, short-chain fatty acid production via intestinal bacterial metabolism was not strongly affected. This study provides the knowledge that MLP administration can alter the gut metabolites without affecting the normal gut microbiota, which is useful for considering MLP as a healthy food source.

The impact of mulberry leaf extract at three different levels on reducing the glycemic index of white bread

In this study, the influences of mulberry leaf extract (MLE) addition on the physicochemical properties including the specific volume, texture and sensory features of white bread (WB) were evaluated by the sensory analysis technology. A double-blind, randomised, repeat-measure design was used to study the impact of MLE addition on the postprandial blood glucose response as well as the satiety index of WB. Results showed that the addition of MLE showed no significant effects on the physicochemical properties of WB except for the slight changes of color and bitterness. The addition of MLE significantly reduced the total blood glucose rise after ingestion of WB over 120 minutes, and reduced the GI value of WB in a dose-effect relationship. When the concentration of MLE reached 1.5 g per 100 g available carbohydrate, the GI value of WB could be reduced from 77 to 43. This study provides important information in terms of the appropriateness of MLE when added to more complex real food, the dose-dependent relationship could supply a reference for the application of MLE.

Effect of mulberry fruit extract on glucose fluxes after a wheat porridge meal: a dual isotope study in healthy human subjects

BACKGROUND

Previous research has shown the efficacy of mulberry extracts for lowering post-prandial glucose (PPG) responses. The postulated mechanism is slowing of glucose absorption, but effects on glucose disposal or endogenous production are also possible. This research assessed the effect of a specified mulberry fruit extract (MFE) on these three glucose flux parameters.

METHODS

The study used a double-blind, randomized, controlled, full cross-over design. In 3 counter-balanced treatments, 12 healthy adult male subjects, mean (SD) age 24.9 (2.50) years and body mass index 22.5 (1.57) kg/m2, consumed porridge prepared from 13C-labelled wheat, with or without addition of 0.75 g MFE, or a solution of 13C-glucose in water. A co-administered 2H-glucose venous infusion allowed for assessment of glucose disposal. Glucose flux parameters, cumulative absorption (time to 50% absorption, T50%abs), and PPG positive incremental area under the curve from 0 to 120 min (+iAUC0-120) were determined from total and isotopically labelled glucose in plasma. As this exploratory study was not powered for formal inferential statistical tests, results are reported as the mean percent difference (or minutes for T50%abs) between treatments with 95% CI.

RESULTS

MFE increased mean T50%abs by 10.2 min, (95% CI 3.9-16.5 min), and reduced mean 2 h post-meal rate of glucose appearance by 8.4% (95% CI -14.9 to -1.4%) and PPG + iAUC0-120 by 11% (95% CI -26.3 to -7.3%), with no significant changes in glucose disposal or endogenous production.

CONCLUSIONS

The PPG-lowering effect of MFE is primarily mediated by a reduced rate of glucose uptake.

Clinical potential and mechanistic insights of mulberry (Morus alba L.) leaves in managing type 2 diabetes mellitus: Focusing on gut microbiota, inflammation, and metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Natural herbs are gradually gaining recognition for their efficacy and safety in preventing diabetes and improving quality of life. Morus alba L. is a plant widely grown in Asia and is a traditional Chinese herb with a long history of use. Furthermore, several parts of Morus alba L. have been found to have significant health benefits. In particular, mulberry (Morus alba L.) leaves (ML) have been shown in human and animal studies to be promising hypoglycemic agents that can reduce or prevent glucolipid metabolism disorders caused by imbalances in the gut microbiota, inflammation, and oxidative stress and have demonstrated significant improvements in glucose metabolism-related markers, effectively lowering blood glucose, and reducing hyperglycemia-induced target organ damage.

AIM OF THE STUDY

This review briefly summarizes the methods for obtaining ML's bioactive components, elaborates on the clinical potential of the relevant components in managing type 2 diabetes mellitus (T2DM), and focuses on the therapeutic mechanisms of gut microbiota, inflammation, oxidative stress, and metabolism, to provide more inspiration and directions for future research in the field of traditional natural plants for the management of T2DM and its complications.

MATERIALS AND METHODS

Research on ML and its bioactive components was mainly performed using electronic databases, including PubMed, Google Scholar, and ScienceNet, to ensure the review's quality. In addition, master's and doctoral theses and ancient documents were consulted.

RESULTS

In clinical studies, we found that ML could effectively reduce blood glucose, glycated hemoglobin, and homeostasis model assessment of insulin resistance in T2DM patients. Furthermore, many in vitro and in vivo experiments have found that ML is involved in various pathways that regulate glucolipid metabolism and resist diabetes while alleviating liver and kidney damage.

CONCLUSIONS

As a potential natural anti-diabetic phytomedicine, an in-depth study of ML can provide new ideas and valuable references for applying traditional Chinese medicine to treat T2DM. While continuously exploring its clinical efficacy and therapeutic mechanism, the extraction method should be optimized to improve the efficacy of the bioactive components. in addition, further research on the dose-response relationship of drugs to determine the effective dose range is required.

A Randomized, Placebo-Controlled Crossover Study to Evaluate Postprandial Glucometabolic Effects of Mulberry Leaf Extract, Vitamin D, Chromium, and Fiber in People with Type 2 Diabetes

INTRODUCTION

Reducing postprandial (PP) hyperglycemia and PP glucose excursions is important for overall glycemic management. Although most therapeutic lifestyle interventions that reduce caloric intake would affect this, there is no particular nutritional intervention favored.

METHODS

We evaluated the effects of a novel natural food adjuvant combining mulberry leaf extract (MLE) with other bioactive ingredients, in people with type 2 diabetes (T2D) originating from Asia, on improving PP glucometabolic response in a randomized controlled exploratory crossover, two-center study (USA, Singapore). A 2-g blend of 250 mg MLE [containing 12.5 mg of 1-deoxynojirimycin (DNJ)], fiber (1.75 g), vitamin D₃ (0.75 μg), and chromium (75 μg), compared with a similar blend without the MLE, was sprinkled over a 350-kcal breakfast meal (55.4 g carbs) and PP blood glucose (primary exploratory endpoint), insulin, and incretin hormones (GLP-1, GIP) were evaluated in blood samples over 3 h. Changes in incremental areas under the concentration curve (iAUC) and maximum concentrations (C_max) were compared.

RESULTS

Thirty individuals (12 women, mean age 59 years, HbA1c 7.1%, BMI 26.5 kg/m²) were enrolled and the MLE-based blend relative to the blend without MLE significantly reduced glucose iAUC at 1 h (- 20%, p < 0.0001), 2 h (- 17%, p = 0.0001), and 3 h (- 15%, p = 0.0032) and C_max [mean (95% CI) difference - 0.8 (- 1.2, - 0.3) mmol/L, p = 0.0006]. A statistically significant reduction in 1 h insulin iAUC (- 24%, p = 0.0236) was observed, but this reduction was no longer present at either 2 h or 3 h. No difference in GLP-1 was seen, but GIP response (iAUC and C_max) was less with the MLE-based blend.

CONCLUSIONS

The observation of a significant glucose reduction paralleled with a significant lower insulin response supports a reduced gastrointestinal glucose absorption. These results support the use of a 2-g natural blend of MLE, fiber, vitamin D, and chromium in T2D as a convenient dietary adjuvant to improve PP glucometabolic response.

CLINICALTRIALS

gov identifier NCT04877366.

Dose-response efficacy of mulberry fruit extract for reducing post-prandial blood glucose and insulin responses: randomised trial evidence in healthy adults

Extracts of mulberry have been shown to reduce post-prandial glucose (PPG) and insulin (PPI) responses, but reliability of these effects and required doses and specifications are unclear. We previously found that 1·5 g of a specified mulberry fruit extract (MFE) significantly reduced PPG and PPI responses to 50 g carbohydrate as rice porridge, with no indications of intolerance. The trials reported here aimed to replicate that work and assess the efficacy of lower MFE doses, using boiled rice as the carbohydrate source. Two separate randomised controlled intervention studies were carried out with healthy Indian males and females aged 20-50 years (n 84 per trial), with PPG area under the curve over 2 h as the primary outcome. Trial 1 used doses of 0, 0·37, 0·75, 1·12 and 1·5 g MFE in boiled rice and 0 or 1·5 g MFE in rice porridge. Trial 2 used doses of 0, 0·04, 0·12, 0·37 g MFE in boiled rice. In trial 1, relative to control, all MFE doses significantly decreased PPG (-27·2 to -22·9 %; all P ≤ 0·02) and PPI (-34·6 to -14·0 %, all P < 0·01). Breath hydrogen was significantly increased only at 1·5 g MFE (in rice porridge), and self-reported gastrointestinal symptoms were uniformly low. In trial 2, only 0·37 g MFE significantly affected PPG (-20·4 %, P = 0·002) and PPI (-17·0 %, P < 0·001). Together, these trials show that MFE in doses as low as 0·37 g can reliably reduce PPG and PPI responses to a carbohydrate-rich meal, with no apparent adverse effects.

Effect of mulberry leaf or mulberry leaf extract on glycemic traits: a systematic review and meta-analysis

Mulberry leaf (ML) and mulberry leaf extract (MLE) have numerous biological properties, such as regulating sugar and lipid metabolism, reducing blood glucose, and increasing insulin secretion. The aim of this study was to perform a systematic review and meta-analysis of randomized clinical trials to examine the effect of ML/MLE supplementation on glycemic traits in adults, including fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), and fasting plasma insulin (FPI). Twelve clinical trials (615 participants) fulfilled the eligibility criteria for the present meta-analysis, which included sensitivity analysis and GRADE (grading of recommendations assessment, development, and evaluation) certainty. Based on the heterogeneity between included studies, a random effects model was applied in the meta-analysis, and the results are expressed as WMD (weighted mean differences) with 95% CI (confidence intervals). Meta-analysis showed that ML/MLE supplementation resulted in a significant reduction in FBG by -0.47 mmol L^-1, HbA1c by -2.92 mmol mol^-1, and FPI by -0.58 μIU mL^-1. In addition, subgroup analysis indicated that long-term supplementation of ML/MLE (≥8 weeks) was more effective for regulation of the glycemic traits in the non-healthy and baseline FPG >6.1 mmol L^-1 subgroups. Glycemic regulation by ML/MLE may be attributed to the phytochemicals they contain, which are mainly 1-deoxynojirimycin, flavonoids, phenolics, and polysaccharides.

Effects of the timing of acute mulberry leaf extract intake on postprandial glucose metabolism in healthy adults: a randomised, placebo-controlled, double-blind study

BACKGROUND/OBJECTIVES

Glucose tolerance is controlled by the internal clock and is worse in the evening. From a chrononutrition perspective, diabetes prevention requires evaluating the antidiabetic effects of the timing of functional ingredients and nutrient intake. The purpose of this study was to investigate the timing effects of acute mulberry leaf extract (MLE) intake on postprandial glucose levels in young adults.

SUBJECTS/METHODS

Twelve young adults underwent four trials. Blood samples were collected in a fasting state and at 30, 60, 120, and 180 min after eating a mixed meal. The study had a randomised, placebo-controlled, double-blind trial design involving: (1) morning placebo trial (08:00 h; MP trial), (2) evening placebo trial (18:00 h; EP trial), (3) morning MLE trial (08:00 h; MM trial), and (4) evening MLE trial (18:00 h; EM trial).

RESULTS

The incremental area under the blood glucose curve (iAUC) in the EM trials was significantly lower than that in the EP trials (P = 0.010). The postprandial glucose concentrations 120 min after the meal were significantly lower in the EM trials than those in the EP trials (P = 0.006). The postprandial insulin concentrations at 120 min were significantly lower in the MM trials than those in the MP trials (P = 0.034). Moreover, the postprandial insulin concentrations 180 min after the meal were significantly lower in the EM trials than those in the EP trials (P = 0.034).

CONCLUSIONS

MLE intake in the evening, but not in the morning, was effective in improving glucose tolerance.

TRIAL REGISTRATION

Clinical trial reference: UMIN 000045301; website of trial registry: https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000051340 .

Impact of mulberry consumption on cardiometabolic risk factors: A systematic review and meta-analysis of randomized-controlled trials

OBJECTIVE

The current study aimed to comprehensively evaluate the potential effects of mulberry consumption on cardiometabolic risk factors in adults.

METHODS

Relevant articles published up to January 2021 were systematically retrieved from SCOPUS, PubMed/MEDLINE, EMBASE, and Web of Science databases. We included all randomized controlled trials (RCTs) investigating the impact of mulberry consumption on various cardiometabolic risk factors.

RESULTS

The quantitative meta-analysis of 12 eligible RCTs demonstrated a significant reducing effect of mulberry consumption on haemoglobin A1c (HbA1c) (weighted mean difference [WMD]: -0. 55, 95% CI: -1.08, -0.02, p = 0.044), serum total cholesterol (TC) (WMD: -13.13 mg/dl, 95% CI: -19.06, -7.20, p < 0.001), low-density lipoprotein levels (LDL-C) (WMD: -8.84 mg/dl, 95% CI: -13.26, -4.42, p < 0.001), triglycerides (TG) (WMD: -19.67 mg/dl, 95% CI: -30.13, -9.22, p < 0.001) and C-reactive protein (CRP) (WMD: -1.60, mg/L, 95% CI: -3.07, -0.12, p = 0.034). Also, >300 mg daily intake of mulberry exhibited a favourable effect on serum high-density lipoprotein levels (HDL-C). However, there were no significant differences between mulberry intervention and control groups for other factors.

CONCLUSION

The current systematic review and meta-analysis revealed that incorporating mulberry into the diet may favourably affect several cardiometabolic risk factors.

Mulberry-Derived 1-Deoxynojirimycin Prevents Type 2 Diabetes Mellitus Progression via Modulation of Retinol-Binding Protein 4 and Haptoglobin

Pre-diabetic or early-stage type 2 diabetes patients may develop an adverse diabetic progression, leading to several complications and increasing hospitalization rates. Mulberry leaves, which contain 1-deoxynojirimycin (DNJ), have been used as a complementary medicine for diabetes prevention and treatment. Our recent study demonstrated that mulberry leaf powder with 12 mg of DNJ improves postprandial hyperglycemia, fasting plasma glucose, and glycated hemoglobin. However, the detailed mechanisms are still unknown. This study investigates the effect of long-term (12-week) supplementation of mulberry leaves in obese people with prediabetes and patients with early-stage type 2 diabetes. Participants’ blood was collected before and after supplementation. The protein profile of the plasma was examined by proteomics. In addition, the mitochondrial function was evaluated by energetic and homeostatic markers using immunoelectron microscopy. The proteomics results showed that, from a total of 1291 proteins, 32 proteins were related to diabetes pathogenesis. Retinol-binding protein 4 and haptoglobin protein were downregulated, which are associated with insulin resistance and inflammation, respectively. For mitochondrial function, the haloacid dehalogenase-like hydrolase domain-containing protein 3 (HDHD-3) and dynamin-related protein 1 (Drp-1) displayed a significant increment in the after treatment group. In summary, administration of mulberry leaf powder extract in prediabetes and the early stage of diabetes can alleviate insulin resistance and inflammation and promote mitochondrial function in terms of energy production and fission.

Comparison of Glycemic Response to Carbohydrate Meals without or with a Plant-Based Formula of Kidney Bean Extract, White Mulberry Leaf Extract, and Green Coffee Extract in Individuals with Abdominal Obesity

Due to the rising prevalence of obesity and type 2 diabetes, a strategy that can positively influence diet quality in a simple way is being explored, since a low glycemic index (GI) diet is advised in the dietoprophylaxis and diet therapy of diabetes. Methods: Twenty-three women with abdominal obesity participated in the study. The postprandial glycemic response and glycemic index were determined after three carbohydrate meals (noodle soup, white rice, strawberry sorbet) without or with the addition of a plant-base supplement (extracts of kidney bean, white mulberry leaf, and green coffee) with a potentially hypoglycemic effect. For two products (instant noodle soup and white rice), the addition of the plant supplement resulted in a reduction in glicemic iAUC values (respectively, by: 17.1%, p = 0.005 and 5.3%; p = 0.03; 40.6%, p = 0.004 and 5.3%, p = 0.019). However, this effect was not observed for strawberry sorbet. The blood glucose concentrations 30 min after the consumption of instant noodle soup and white rice with the plant-based formula addition significantly affected the GI value of tested meals (p = 0.0086, r = 0.53; p = 0.0096, r = 0.53), which may indicate the effect of this plant supplement on enterohormone and/or insulin secretion. Conclusion: A formula containing kidney bean, white mulberry leaves, and green coffee extracts may therefore be a notable factor in lowering postprandial glycemia and the GI of carbohydrate foods. However, further research is needed to determine for which food groups and meals its use may be most effective.

Mulberry leaf meal: A potential feed supplement for juvenile Megalobrama amblycephala "Huahai No. 1"

This study was performed to evaluate the potential application of mulberry leaf meal (ML) and fermented mulberry leaf meal (FML) as feed supplements in aquatic animals for developing varieties of practical and economical feed ingredients. Juveniles Megalobrama amblycephala were fed a basal diet (35.7% crude protein, 10.4% crude lipid; control group) supplemented with 2.22% and 4.44% mulberry leaf meals (ML2, ML4) and fermented mulberry leaf meals (FML2, FML4) for 8 weeks. Generally, the two-way ANOVA showed the supplementation level exhibited a prominent effect on the growth performance and physiological status of fish. Furthermore, the two-way ANOVA showed the supplementary fermented mulberry leaf meal increased plasma complement 4 (C4) content (P < 0.05). The weight gain rate (WGR, 145.87%) and the specific growth rate (SGR, 1.63%) were significantly increased in FML2 group compared with the control group (P < 0.05). The muscle crude lipid content and hepatosomatic index (HSI) were higher in FML2 group than that in ML2 group (P < 0.05). The hepatic GSH content in ML4 group and CAT, T-SOD activities in FML4 group were significantly increased compared with the control group (P < 0.05). The hepatic MDA content in FML4 group was significantly decreased compared with the FML2 group (P < 0.05). Total cholesterol (TC) contents showed a significant decrease in ML4 and FML4 groups compared with the control group (P < 0.05). Regarding the gene expression, sirtiun 1 (Sirt1) gene expression was elevated in FML2 group compared with the ML2 group (P < 0.05). Compare to the control group, FML2 diet significantly increased the expression of i-kappa-B alpha (IKBα) gene in liver, and decreased the expression of forkhead box O1 α (FoxO1α), toll-like receptors 4 (TLR4) and nuclear factor-kappa B (NF-κB) genes (P < 0.05). In conclusion, 2.22% FML promoted the growth performance of M. amblycephala and enhanced the anti-inflammatory responses by inhibiting TLR4/NF-κB signaling pathway. On the other hand, 4.44% FML reduced plasma lipid content (hypolipedemic effect) and improved the hepatic antioxidant capacity of M. amblycephala.

13C-sucrose breath test for the non-invasive assessment of environmental enteropathy in Zambian adults

Objectives

Environmental enteropathy (EE) is a subclinical disorder highly prevalent in tropical and disadvantaged populations and is thought to play a role in growth faltering in children, poor responses to oral vaccines, and micronutrient deficiencies. This study aims to evaluate the potential of a non-invasive breath test based on stable isotopes for evaluation of impaired digestion and absorption of sucrose in EE.

Methods

We optimized a ¹³C-sucrose breath test (¹³C-SBT) in 19 young adults in Glasgow, United Kingdom. In a further experiment (in 18 adults) we validated the ¹³C-SBT using Reducose, an intestinal glucosidase inhibitor. We then compared the ¹³C-SBT to intestinal mucosal morphometry, immunostaining for sucrose-isomaltase (SI) expression, and SI activity in 24 Zambian adults with EE.

Results

Fully labeled sucrose (0.3 mg/kg) provided clear breath enrichment signals over 2–3 h in both British and Zambian adults, more than fivefold higher than naturally enriched sucrose. Reducose dramatically impaired ¹³C-sucrose digestion, reducing 4 h ¹³CO₂ breath recovery by > 50%. Duodenal biopsies in Zambian adults confirmed the presence of EE, and SI immunostaining was present in 16/24 adults. The kinetics of ¹³CO₂ evolution were consistently faster in participants with detectable SI immunostaining. Although sucrase activity was strongly correlated with villus height (r = 0.72; P < 0.05) after adjustment for age, sex and body mass index, there were no correlations between ¹³C-SBT and villus height or measured sucrase activity in pinch biopsies.

Conclusion

A ¹³C-SBT was developed which was easy to perform, generated clear enrichment of ¹³CO₂ in breath samples, and clearly reports sucrase activity. Further work is needed to validate it and understand its applications in evaluating EE.

Characterization of Purified Mulberry Leaf Glycoprotein and Its Immunoregulatory Effect on Cyclophosphamide-Treated Mice

Mulberry leaf protein is a potentially functional food component and health care agent with antioxidant and anti-inflammatory properties. However, its composition, immunoregulatory effects, and gut microbial regulatory effects are unclear. Herein, ultra-filtrated and gel-fractionated mulberry leaf protein (GUMP) was characterized. Its effects on cyclophosphamide-induced immunosuppressed mice were further investigated. The results indicated that GUMP is a glycoprotein mainly containing glucose, arabinose, and mannose with 9.23% total sugar content. Its secondary structure is mainly β-sheet. LC–MS/MS analysis showed that GUMP closely matched with a 16.7 kDa mannose-binding lectin and a 52.7 kDa Rubisco’s large subunit. GUMP intervention significantly improved serous TNF-α, IL-6, and IL-2 contents; increased serum immunoglobulins (IgA and IgG) levels; and reversed splenic damage prominently. Moreover, GUMP administration increased fecal shot-chain fatty acid concentration and up-regulated the relative abundance of Odoribacter, which was positively correlated with SCFAs and cytokine contents. Overall, GUMP alleviated immunosuppression through the integrated modulation of the gut microbiota and immune response. Therefore, GUMP could be a promising dietary supplement to help maintain gut health.

Effect of Different Nutritional Supplements on Glucose Response of Complete Meals in Two Crossover Studies

Postprandial hyperglycemia is an important risk factor in the development and progression of type-2 diabetes and cardiometabolic diseases. Therefore, maintaining a low postprandial glucose response is key in preventing these diseases. Carbohydrate-rich meals are the main drivers of excessive glycemic excursions during the day. The consumption of whey protein premeals or mulberry leaf extract was reported to reduce postprandial glycemia through different mechanisms of action. The efficacy of these interventions was shown to be affected by the timing of the consumption or product characteristics. Two randomised crossover studies were performed, aiming to identify the optimal conditions to improve the efficacy of these nutritional supplements in reducing a glycemic response. The acute postprandial glycemic response was monitored with a continuous glucose monitoring device. The first study revealed that a preparation featuring 10 g of whey protein microgel reduced the postprandial glucose response by up to 30% (p = 0.001) and was more efficient than the whey protein isolates, independently of whether the preparation was ingested 30 or 10 min before a complete 320 kcal breakfast. The second study revealed that a preparation featuring 250 mg mulberry leaf extract was more efficient if it was taken together with a complete 510 kcal meal (−34%, p < 0.001) rather than ingested 5 min before (−26%, p = 0.002). These findings demonstrate that the efficacy of whey proteins premeal and mulberry leaf extracts can be optimised to provide potential nutritional solutions to lower the risk of type-2 diabetes or its complications.

Morus Alba leaf extract affects metabolic profiles, biomarkers inflammation and oxidative stress in patients with type 2 diabetes mellitus: A double-blind clinical trial

INTRODUCTION

Morus Alba extract, despite its special properties, has been less studied in terms of its effects on metabolic profiles in patients with type 2 diabetes mellitus (T2DM). This study was carried out to determine the effects of Morus Alba extract, known as white mulberry, on liver enzymes, biomarkers of inflammation and oxidative stress, insulin metabolism and lipid profiles in patients with T2DM.

METHODS

The current randomized, double-blind, placebo-controlled trial was conducted among 60 patients with T2DM. Subjects were randomly divided into 2 groups to receive either Morus Alba extract (300 mg) (n = 30) or placebo (n = 30) twice a day. Fasting blood samples were collected at the baseline and 12 weeks after intervention to quantify related markers.

RESULTS

Morus Alba extract intake significantly decreased insulin (P = 0.026) and malondialdehyde (MDA) (P < 0.001), and significantly increased HDL-cholesterol concentrations (P = 0.001) compared with the placebo. However, Morus Alba extract intake did not affect other metabolic profiles.

CONCLUSIONS

The results of this study shown that the 12-week administration of Morus Alba extract among subjects with T2DM had beneficial effects on HDL-cholesterol, insulin and MDA levels, but did not affect other metabolic profiles. The present study was registered in the Iranian website for clinical trials as http://www.irct.ir: IRCT2016081312438N21.

Morus alba L. for Blood Sugar Management: A Systematic Review and Meta-Analysis

Introduction

Morus alba L. is used for blood sugar management in patients with diabetes mellitus. This review aimed to evaluate the effect of Morus alba on blood sugar management.

Methods

This review was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). We searched PubMed, EMBASE, and four Korean medical databases (RISS, OASIS, NDSL, and KISS) using relevant keywords. Randomized controlled trials with any type of control intervention were included. The selection of studies, data extraction, and quality assessment were performed independently by two researchers.

Results

Our results showed that Morus alba can reduce postprandial glucose and insulin levels. However, it is insufficient to conclude that Morus alba is an effective intervention for lowering blood glucose levels. Therefore, more rigorous studies are needed to reveal the effect of MA on blood glucose levels.

Conclusion

The conclusion of this review provides evidence that Morus alba can control blood sugar level. This systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42021255940).

Mulberry (Morus alba L.) leaf polysaccharide ameliorates insulin resistance- and adipose deposition-associated gut microbiota and lipid metabolites in high-fat diet-induced obese mice

Dietary supplements are currently being used to ameliorate metabolic alterations via maintaining gut microflora balance. Mulberry leaf is known as medicine homologous food for its glucose- and lipid-modulating properties. However, the effects of mulberry leaf polysaccharide (MP) on metabolic dysbiosis and gut microbiota are still poorly understood. After extraction and characterization, the beneficial effects of water-soluble MP were evaluated in high-fat diet-induced obese mice. MP treatment could reduce adipose tissue, improve insulin resistance, and alleviate the pathological lesions in colon. Investigation of the underlying mechanism showed that MP modulated gut microbial community by 16S rRNA analysis and reversed the elevation of lipid indexes by plasma lipidomics analysis. Correlation analysis indicated that the abundance of seven key bacterial species and six lipids were closely associated with the metabolic traits, respectively. Overall, MP could ameliorate metabolic disorders, and modify the gut microbiota and lipids. This would greatly facilitate the utilization of MP as a functional food.

A Narrative Review of Human Clinical Trials on the Impact of Phenolic-Rich Plant Extracts on Prediabetes and Its Subgroups

Phenolic-rich plant extracts have been demonstrated to improve glycemic control in individuals with prediabetes. However, there is increasing evidence that people with prediabetes are not a homogeneous group but exhibit different glycemic profiles leading to the existence of prediabetes subgroups. Prediabetes subgroups have been identified as: isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT), and combined impaired fasting glucose and glucose intolerance (IFG/IGT). The present review investigates human clinical trials examining the hypoglycemic potential of phenolic-rich plant extracts in prediabetes and prediabetes subgroups. Artemisia princeps Pampanini, soy (Glycine max (L.) Merrill) leaf and Citrus junos Tanaka peel have been demonstrated to improve fasting glycemia and thus may be more useful for individuals with IFG with increasing hepatic insulin resistance. In contrast, white mulberry (Morus alba Linn.) leaf, persimmon (Diospyros kaki) leaf and Acacia. Mearnsii bark were shown to improve postprandial glycemia and hence may be preferably beneficial for individuals with IGT with increasing muscle insulin resistance. Elaeis guineensis leaf was observed to improve both fasting and postprandial glycemic measures depending on the dose. Current evidence remains scarce regarding the impact of the plant extracts on glycemic control in prediabetes subgroups and therefore warrants further study.

Mulberry leaf extract improves glycaemic response and insulaemic response to sucrose in healthy subjects: results of a randomized, double blind, placebo-controlled study

Background

There are many benefits of maintaining healthy blood glucose levels, and studies have shown that lifestyle changes such as changes to diet can successfully restore normoglycaemia in participants with dysglycaemia. Significant health-related lifestyle changes are often difficult to implement and functional ingredients that can reduce glycaemic and insulaemic responses may help at risk populations. The aim of this study was to investigate whether a mulberry leaf extract could lower the glycaemic and insulinaemic responses to 75 g sucrose in healthy individuals.

Methods

A double-blind, randomised, placebo-controlled, crossover design trial was conducted by the Oxford Brookes Centre for Nutrition and Health. Thirty-eight participants were recruited into the trial and, after an overnight fast, were given 75 g sucrose + white mulberry leaf extract, or 75 g sucrose alone. Capillary blood samples were collected at 15-min intervals in the first hour and at 30-min intervals over the second hour to determine glucose and plasma insulin levels. Data analysis was conducted using a paired samples T test or a Wilcoxon signed rank test.

Results

The addition of mulberry leaf extract to sucrose resulted in a significantly lower glycaemic response and insulinaemic response compared to a matched placebo (sucrose alone). The change in blood glucose measurements were significantly lower at 15 min (p < 0.001), 30 min (p < 0.001), 45 min (p = 0.008), and 120 min (p < 0.001) and plasma insulin measurements were significantly lower at 15 min (p < 0.001), 30 min (p < 0.001), 45 min (p < 0.001), 60 min (p = 0.001) and 120 min (p < 0.001). The glucose iAUC (− 42%, p = 0.001), insulin iAUC (− 40%, p < 0.001), peak glucose (− 40.0%, p < 0.001) and peak insulin (− 41%, p < 0.001) from baseline were significantly lower for white mulberry leaf extract compared with the placebo. White mulberry leaf extract was well tolerated and there were no reported adverse events.

Conclusions

Mulberry leaf extract can be used as part of lifestyle changes that may lead to healthy blood glucose levels.

Trial registration: ISRCTN99601810 (23 October 2020, retrospectively registered)

The effect of 8 plant extracts and combinations on post-prandial blood glucose and insulin responses in healthy adults: a randomized controlled trial

BACKGROUND

Lower post-prandial glucose (PPG) and insulin (PPI) responses to foods are associated with reduced diabetes risk and progression. Several plant extracts have been proposed to reduce PPG or PPI by inhibiting enzymes or transporters involved in carbohydrate digestion and uptake. This study evaluates a range of such extracts, consumed with a carbohydrate load, for their effects on PPG, PPI and indicators of (gastrointestinal) tolerance.

METHODS

Interventions were extracts of mulberry fruit (MFE, 1.5 g), mulberry leaf (MLE, 1.0 g), white bean (WBE, 3.0 g), apple (AE, 2.0 g), elderberry (EE, 2.0 g), turmeric (TE, 0.18 g), AE + TE, and EE + TE. Each of these 8 individual extracts or combinations were added to a rice porridge containing ~ 50 g available carbohydrate (control). In a within-subject (randomised, balanced incomplete block) design, individual subjects received the control and a subset of 4 of the 8 extracts or combinations. Participants were 72 apparently healthy adults (mean [SD] age 31.2 [5.5] yr, body mass index 22.1 [2.0] kg/m2). The primary outcome was the percentage change in 2-h PPG (positive incremental area under the curve) relative to control. Secondary measures were the 2-h PPI response, 7-h breath hydrogen, measures of gastrointestinal discomfort, and urine glucose.

RESULTS

In the 65 subjects who completed the control and at least one intervention treatment, additions of AE, MFE and MLE produced statistically significant reductions in PPG vs control (p < 0.05; mean effect - 24.1 to - 38.1%). All extracts and combinations except TE and WBE significantly reduced PPI (p < 0.01; mean effect - 17.3% to - 30.4%). Rises in breath hydrogen > 10 ppm were infrequent, but statistically more frequent than control only for MLE (p = 0.02). Scores for gastrointestinal discomfort were extremely low and not different from control for any treatment, and no glucosuria was observed.

CONCLUSIONS

Additions of AE, MFE and MLE to rice robustly reduced PPG and PPI. EE significantly reduced only PPI, while TE and WBE showed no significant efficacy for PPG or PPI. Breath hydrogen responses to MLE suggest possible carbohydrate malabsorption at the dose used, but there were no explicit indications of intolerance to any of the extracts.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04258501. Registered 6 February 2020 - Retrospectively registered.

Comparison Among Garlic, Berberine, Resveratrol,Hibiscus sabdariffa, GenusZizyphus, Hesperidin, Red Beetroot,Catha edulis,Portulaca oleracea, and Mulberry Leaves in the Treatment of Hypertension and Type 2 DM: A Comprehensive Review

Diabetes mellitus (DM) and hypertension are 2 of the most prevalent diseases with poor impact on health status worldwide. In most cases, they coexist with other metabolic disorders as well as cardiac, micro- and macrovascular complications. Many plants are known for their hypotensive, cardioprotective, and/or antidiabetic activities. Their active ingredients either identified and isolated or still utilized as herbal preparations of certain plant parts. The use of medicinal plants comprises the main basis for most of the traditional medicine (TM) systems and procedures. As conventional medicines seem insufficient to control such progressive diseases, herbal agents from TM could be used as adjuvant with good impact on disease control and progression as well as other concomitant health conditions. The aim of this study is to compare the efficacy of 10 different herbal medicines of botanical origin or herbal preparations in the management of hypertension and its cardiovascular complications and type 2 DM along with various coexisting health disorders. These herbal medicines are garlic, berberine, resveratrol, Hibiscus sabdariffa, Zizyphus ( oxyphylla, mucronate, jujube, rugosa), hesperidin, red beetroot, Catha edulis, mulberry leaves, and Portulaca oleracea.

Dietary supplementation of Morus nigra L. leaves decrease fat mass partially through elevating leptin-stimulated lipolysis in pig model

ETHNOPHARMACOLOGICAL RELEVANCE

Mulberry leaves are the dry leaves of Morus nigra L. trees, which are widely cultivated in central and southern China. Mulberry has a long history of medicinal use, such as anti-stress, lowering blood glucose and anti-obesity.

AIM OF THE STUDY

Explore the effects of mulberry leaves on fat deposition as well as the underlying mechanisms.

MATERIALS AND METHODS

Total of 48 fattening pigs weighing about 70 kg were randomly allotted to normal diet or die supplemented with 5% (w/w) mulberry leave powder. Changes of fat mass, indicated by backfat thickness was measured with Piggyback tester, blood triglyceride and cholesterol were tested using commercial biochemical kits, serum hormones were estimated by ELISA, and leptin-related signaling activity were assessed using western-blot.

RESULTS

Supplementation with Mulberry leaf feed (MF) significantly reduced serum triglyceride and free cholesterol concentrations and increased the ratio of high-density lipoprotein cholesterol (HDL-c) to low-density lipoprotein cholesterol (LDL-c), while serum glucose and free fatty acids remained unchanged. Dietary MF resulted in a significant reduction in the size of adipocytes and backfat thickness (P < 0.05). Accordingly, hormone-sensitive lipase (HSL) in backfat was significantly up-regulated and fatty acid synthase (FAS) was down-regulated by MF supplementation (both P < 0.05). Furthermore, MF supplementation significantly elevated circulating leptin and adiponectin without influencing serum insulin and glucocorticoid. Moreover, significantly higher leptin receptor (Leptin-R) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) were detected in MF-supplemented pigs, suggesting an enhanced leptin signaling induced by MF in the subcutaneous fat.

CONCLUSIONS

Mulberry leaves have obvious anti-obesity effects, providing a theoretical basis for the development of mulberry leaves as a drug against obesity.

Fruits

Fruits come in a wide variety of colors, shapes, and flavors. This chapter will cover selected fruits that are known to be healthy and highly nutritious. These fruits were chosen due to their common usage and availability. Since it is not possible to cover all health benefits or essential nutrients and important phytochemicals of the fruit composition, this chapter will focus on the key valuable constituents and their potential health effects.

The Protective Effects of Cryptochlorogenic Acid on β-Cells Function in Diabetes in vivo and vitro via Inhibition of Ferroptosis

PURPOSE

Mulberry leaf extract has exerted better antidiabetic activities, while the effects of major active components in mulberry leaf extract are still unclear. Cryptochlorogenic acid (CCA) as the major active component in mulberry leaf extracts was investigated herein.

MATERIALS AND METHODS

Rats were treated with 50mg/kg streptozotocin for the establishment of diabetic model in vivo, and cells were treated with 33.3 mM glucose for the establishment of cell model in vitro. HE staining assay was performed for observation of pancreatic pathology and aldehyde fuchsin staining assay for examining islet cell numbers. The iron content was detected via Perls staining assay with iron assay kit (ab83366). The malondialdehyde (MDA), glutathione (GSH) and oxidized glutathione (GSSG) were detected by corresponding kits. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed for assessment of gene level and Western blot for measurement of protein expression level. The cell survival was detected via CCK-8 assay.

RESULTS

The blood glucose level, iron content, accumulation of lipid peroxides and islet injury in diabetic model were all improved by CCA via a concentration-dependent manner. CCA functions via inhibition of ferroptosis by activation of cystine/glutamate transporter system (XC^-)/glutathione peroxidase 4(GPX4)/Nrf2 and inhibition of nuclear receptor coactivator 4 (NCOA4) in diabetes.

CONCLUSION

CCA exerted excellent antidiabetic effects via inhibition of ferroptosis, so it may be a promising agent for diabetes therapy, providing a new avenue for diabetes treatment.

Isolation and hypoglycemic effects of water extracts from mulberry leaves in Northeast China

Diabetes is the main chronic disease that greatly affects human life.

Guava (Psidium guajava) Fruit Extract Prepared by Supercritical CO2 Extraction Inhibits Intestinal Glucose Resorption in a Double-Blind, Randomized Clinical Study

Inhibition of intestinal glucose resorption can serve as an effective strategy for the prevention of an increase in blood glucose levels. We have recently shown that various extracts prepared from guava (Psidium guajava) inhibit sodium-dependent glucose cotransporter 1 (SGLT1)- and glucose transporter 2 (GLUT2)-mediated glucose transport in vitro (Caco-2 cells) and in vivo (C57BL/6N mice). However, the efficacy in humans remains to be confirmed. For this purpose, we conducted a parallelized, randomized clinical study with young healthy adults. Thirty-one volunteers performed an oral glucose tolerance test (OGTT) in which the control group received a glucose solution and the intervention group received a glucose solution containing a guava fruit extract prepared by supercritical CO₂ extraction. The exact same extract was used for our previous in vitro and in vivo experiments. Blood samples were collected prior to and up to two hours after glucose consumption to quantitate blood glucose and insulin levels. Our results show that, in comparison to the control group, consumption of guava fruit extract resulted in a significantly reduced increase in postprandial glucose response over the basal fasting plasma glucose levels after 30 min (Δ control 2.60 ± 1.09 mmol/L versus Δ intervention 1.96 ± 0.96 mmol/L; p = 0.039) and 90 min (Δ control 0.44 ± 0.74 mmol/L versus Δ intervention -0.18 ± 0.88 mmol/L; p = 0.023). In addition, we observed a slightly reduced, but non-significant insulin secretion (Δ control 353.82 ± 183.31 pmol/L versus Δ intervention 288.43 ± 126.19 pmol/L, p = 0.302). Interestingly, storage time and repeated freeze-thawing operations appeared to negatively influence the efficacy of the applied extract. Several analytical methods (HPLC-MS, GC-MS, and NMR) were applied to identify putative bioactive compounds in the CO₂ extract used. We could assign several substances at relevant concentrations including kojic acid (0.33 mg/mL) and 5-hydroxymethylfurfural (2.76 mg/mL). Taken together, this clinical trial and previous in vitro and in vivo experiments confirm the efficacy of our guava fruit extract in inhibiting intestinal glucose resorption, possibly in combination with reduced insulin secretion. Based on these findings, the development of food supplements or functional foods containing this extract appears promising for patients with diabetes and for the prevention of insulin resistance. Trial registration: 415-E/2319/15-2018 (Ethics Commissions of Salzburg).

Study of the effect of the herbal composition SR2004 on hemoglobin A1c, fasting blood glucose, and lipids in patients with type 2 diabetes mellitus

Background

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by raised blood glucose levels and peripheral insulin resistance. It is an increasingly prevalent global healthcare concern. Conventional treatment options are limited and in this context, there is renewed interest in evaluating the clinical and biological effects of traditional therapies. We assess the effect of a new herbal composition SR2004 on the hemoglobin A1c (HbA1c), fasting blood glucose, and lipid profiles of patients with T2DM.

Methods

This is a single center, unblinded, prospective interventional study conducted in Israel. The composition SR2004 includes Morus alba, Artemisia dracunculus, Urtica dioica, Cinnamomum zeylanicum, and Taraxacum officinale. One hundred and nineteen patients with diagnosed T2DM were enrolled and received SR2004 in addition to their usual medications. HbA1c, fasting blood glucose, and lipid profiles at 12 weeks were compared with baseline. In addition, the tolerability and side effects of SR2004 were recorded.

Results

One hundred and three patients completed 12 weeks of follow-up (87%) and were included in the results. At 12 weeks, HbA1c reduced from 9.0% to 7.1% (22%; p < 0.0001), mean blood glucose decreased from 211 mg/dL to 133 mg/dL (37% reduction; p < 0.0001), mean total cholesterol to 185 mg/dL (13% reduction; p < 0.01) and mean serum triglycerides to160 mg/dL (a reduction of 40% from baseline; p < 0.001). Twelve patients (12%) had no response with SR2004 supplementation. In addition, of thirteen patients who took insulin at baseline, five required only oral hypoglycemics and another five reduced their daily insulin requirements by 30% at 12 weeks. Clinical observations included improvements in vasculopathy, including reversal of established retinopathic changes in two patients.

No major adverse effects were observed, with minor abdominal symptoms reported in sixteen patients (16%).

Conclusion

SR2004 supplementation significantly reduced HbA1c, blood glucose, and lipids with good tolerability and no observed adverse interactions with conventional medications. Some interesting findings relating to the reversal of microvascular phenomena warrant further research to elucidate the mechanisms of action of this novel composition.