Mulberry leaf extract inhibits the development of atherosclerosis in cholesterol-fed rabbits and in cultured aortic vascular smooth muscle cells

Effects of Mulberry Leaf Extract on the Liver Function of Juvenile Spotted Sea Bass (Lateolabrax maculatus)

In order to explore the effect of mulberry leaf extract (ELM) on the liver function of spotted sea bass, 360 fish with healthy constitution (average body weight 9.00 ± 0.02 g) were selected and randomly divided into six groups with three repetitions, and six groups of fish were randomly placed into 18 test tanks (200 L) with 20 fish per tank for the 52-day feeding test. Every day, the fish were fed the experimental feed with different concentrations (0, 3, 6, 9, 12, 15 g/kg) to the level of apparent satiation, with a crude protein content of 48.0% and a crude fat content of 8.6%. And the water temperature was maintained at 25-28°C with a salinity of 0.5%-1‰. After feeding, five fish were randomly selected to collect their livers and serum for detection of indicators. The results showed that, compared with the control group, ELM significantly increased the activities of lipase (LPS) and trypsin (TRS) in the liver, and reached the highest level when the amount of ELM added was 6 g/kg (P < 0.05). ELM significantly increased the activities of lactate dehydrogenase (LDH) and glutamic-oxaloacetic transaminase (GOT) involved in the metabolic process in liver tissue, and GOT activity reached the highest when ELM was added at 9 g/kg, and LDH activity reached the highest when ELM was added at 15 g/kg (P < 0.05). ELM had no significant effect on liver antioxidant enzymes (P > 0.05), but the content of malondialdehyde was significantly reduced (P < 0.05). Compared with the control group, ELM significantly increased the activities of AKP and ACP in the liver, and the AKP activity reached the highest when the ELM addition amount was 3 g/kg, and the ACP activity reached the highest when the ELM addition amount was 9 g/kg (P < 0.05). Through comparative transcriptomic analysis, it was indicated that ELM enhanced the hepatic lipids and carbohydrates metabolism ability, as manifested in the upregulation of expression of phosphatidate phosphatase, glucuronosyltransferase, inositol oxygenase, carbonic anhydrase, and cytochrome c oxidase subunit 2. ELM can also increase the expression of signal transducer and activator of transcription 1, ATP-dependent RNA helicase and C-X-C motif chemokine 9 involved in the immune process. The above results show that the ELM can enhance the digestion, metabolism, and immunity of the liver by increasing the activity of digestive enzymes, metabolic enzymes, and the expression of metabolism and immune regulation genes. This study provides a theoretical basis for the application of ELM in the cultivation of spotted sea bass by exploring the effect of ELM on the liver function of spotted sea bass.

Morus alba: a comprehensive phytochemical and pharmacological review

Morus alba is a fast-growing shrub or medium-sized tree with a straight, cylindrical trunk. Medicinally, whole plants, leaves, fruits, branches, and roots have been employed. Google Scholar, PubMed, Scopus, and Web of Science were used to search for relevant material on the phytochemical components and pharmacologic and mechanism of action of the Morus alba. This was reviewed to assess important updates about Morus alba. The fruits of Morus alba have traditionally been used as an analgesic, anthelmintic, antibacterial, anti-rheumatic, diuretic, hypotensive, hypoglycemia, purgative, restorative, sedative tonic, and blood stimulant. Various plant parts were used as a cooling, sedating, diuretic, tonic, and astringent agent to treat nerve disorders. The plant contained tannins, steroids, phytosterols, sitosterol, glycosides, alkaloids, carbohydrates, proteins, and amino acids, as well as saponins, triterpenes, phenolics, flavonoids, benzofuran derivatives, anthocyanins, anthraquinones, glycosides, vitamins, and minerals. Previous pharmacological research identified antimicrobial, anti-inflammatory, immunological, analgesic, antipyretic, antioxidant, anti-cancer, antidiabetic, gastrointestinal, respiratory, cardiovascular, hypolipidemic, anti-obesity, dermatological, neurological, muscular, and protecting effects. This study looked at Morus alba's traditional uses, chemical components, and pharmacological effects.

Investigation on Antioxidant Activity and Different Metabolites of Mulberry (Morus spp.) Leaves Depending on the Harvest Months by UPLC-Q-TOF-MS with Multivariate Tools

The changes in active components in mulberry leaves harvested in different months and their antioxidant activities were investigated. Ultra-high-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) with multivariate statistical tools was used to investigate the chemical constituents in the extracts of mulberry leaves. The results indicated that mulberry leaves were rich in phenolic acids, flavonoids, organic acids, and fatty acid derivatives. In addition, 25 different compounds were identified in the different batches of mulberry leaves. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was measured to evaluate the in vitro antioxidant activities of mulberry leaves. Among the four batches, batch A, harvested in December, exhibited the strongest DPPH radical-scavenging activity, while batch B, harvested in March, showed the weakest activity. This was related to the total phenolic content in the mulberry leaves of each batch. The optimal harvest time of mulberry leaves greatly influences the bioactivity and bioavailability of the plant.

Biotechnological Approach to Increase Oxyresveratrol Production in Mulberry In Vitro Plants under Elicitation

Morus alba L. is used for a range of therapeutic purposes in Asian traditional medicine, and its extracts are reported to be effective against lipidemia, diabetes, and obesity, as well as being hepatoprotective and tyrosinase-inhibitory. They are also included in cosmetic products as anti-aging and skin-whitening agents. Stilbenes, the major bioactive compounds found in M. alba, have received renewed attention recently because of their putative activity against COVID-19. In this study M. alba plants were established in vitro, and the effect of elicitation on plant growth and stilbene accumulation, specifically oxyresveratrol and trans-resveratrol, was investigated. Different concentrations of the elicitors including methyl jasmonate and cyclodextrins were applied, and stilbene levels were determined in leaves, roots, and the culture medium. Elicitation of the M. alba plants with 5 mM cyclodextrins, alone or in combination with 10 µM methyl jasmonate, significantly increased the total phenolic content in the culture medium and leaves after 7 days of treatment. The higher total phenolic content in the roots of control plants and those treated only with methyl jasmonate indicated that cyclodextrins promoted metabolite release to the culture medium. Notably, the cyclodextrin-treated plants with the highest levels of oxy- and trans-resveratrol also had the highest total phenolic content and antioxidant capacity. These results indicate that elicited M. alba in vitro plants constitute a promising alternative source of bioactive stilbenes to supply pharmaceutical and cosmeceutical industries.

Effects of white mulberry powder fortification on antioxidant activity, physicochemical, microbial and sensorial properties of yogurt produced from buffalo milk

The objective of this study was to investigate the effects of sun-dried white mulberry fruit powder (WMFP) at addition levels of 2%, 4%, and 6% for enhancing nutritional value and improving the quality of yogurt during refrigerated storage. Results showed that the highest (p < .05) antioxidant activity of 54.53 ± 0.15% was observed in 6% WMFP-added yogurt samples. Highest pH of 4.53 ± 0.08 was observed in control. Significantly highest (p < .05) acidity (1.12 ± 0.02%) was recorded in the yogurt with 6% WMFP-added yogurt samples on 28th day. Moreover, the addition of WMFP elevated the total soluble solids up to 20.05 ± 0.02 °Brix and water-holding capacity up to 55.06 ± 0.34% and lessened the syneresis value (22.92 ± 0.25) in 6% yogurt samples. 2% WMFP-added yogurt sample was given the highest sensory score in terms of overall acceptability by the panelists (8.00 ± 0.00). Thus, it was concluded that fruit powder of white mulberry can be used to improve physicochemical and sensory properties of fortified yogurt. WMFP addition to yogurt enhanced its antioxidant potential and physicochemical quality. The study introduces white mulberry-enriched yogurt and suggests the food industries to launch this product in the market.

Mulberry Leaf and Neochlorogenic Acid Alleviates Glucolipotoxicity-Induced Oxidative Stress and Inhibits Proliferation/Migration via Downregulating Ras and FAK Signaling Pathway in Vascular Smooth Muscle Cell

Mulberry leaf (Morus alba L.) has been used as a health food and in traditional medicine to treat several metabolic diseases, including diabetes, hypertension, and hyperlipidemia. However, the mechanism by which mulberry leaf and its functional components mediate atherosclerosis remains unclear. This study aimed to determine the effect of mulberry leaf extract (MLE) and its major component, neochlorogenic acid (nCGA), on the proliferation and migration of rat aortic vascular smooth muscle cells (VSMCs, A7r5 cell line) under diabetic cultured conditions (oleic acid and high glucose, OH). Our findings showed that MLE and nCGA significantly inhibited cell proliferation and migration in A7r5 cells as determined by a scratch wound assay and a Transwell assay. Furthermore, we observed MLE and nCGA inhibited cell proliferation and migration, such as reducing the phosphoinositide 3-kinases (PI3K)/protein kinase B (Akt), focal adhesion kinase (FAK), and small GTPase proteins using Western blot analysis. In conclusion, we confirmed the anti-atherosclerotic effects of MLE and nCGA in reducing vascular smooth muscle cell (VSMC) migration and proliferation under diabetic cultured conditions via inhibition of FAK/small GTPase proteins, PI3K/Akt, and Ras-related signaling.

Anti-Inflammatory and Anti-Bacterial Potential of Mulberry Leaf Extract on Oral Microorganisms

Mulberry leaves extract (Morus alba extracts; MAE) is known to have therapeutic potentials for numerous human diseases, including diabetes, neurological disorders, cardiovascular diseases, and cancers. However, there has not been sufficient research proving therapeutic effects on oral disease and its related oral risk factors. Thus, we investigated whether MAE has any anti-inflammatory and anti-bacterial effects on risk factors causing oral infectious diseases. To examine the anti-inflammatory response and bacterial inhibition of MAE, we measured intracellular reactive oxygen species (ROS) generation, production of pro-inflammatory cytokines, and the bacterial growth rate. Our study showed that MAE has anti-inflammatory activities, which inhibit the ROS generation and suppressed the production of pro-inflammatory cytokines (TNF-α and IL-6) in human monocyte THP-1 cells by stimulating lipopolysaccharide (LPS) and/or F. nucleatum, which are the virulent factors in periodontal diseases. Furthermore, MAE inhibited the bacterial growth on oral microorganisms (F. nucleatum and S. mutans) infected THP-1 cells. These findings suggested that MAE could be a potential natural source for therapeutic drugs in oral infectious disease.

Mulberry leaf (Morus alba L.): A review of its potential influences in mechanisms of action on metabolic diseases

The leaves of Morus alba L. (called Sangye in Chinese, ML), which belong to the genus Morus., are highly valuable edible plants in nutrients and nutraceuticals. In Asian countries including China, Japan and Korea, ML are widely used as functional foods including beverages, noodles and herbal tea because of its biological and nutritional value. Meanwhile, ML-derived products in the form of powders, extracts and capsules are widely consumed as dietary supplements for controlling blood glucose and sugar. Clinical studies showed that ML play an important role in the treatment of metabolic diseases including the diabetes, dyslipidemia, obesity, atherosclerosis and hypertension. People broadly use ML due to their nutritiousness, deliciousness, safety, and abundant active benefits. However, the systematic pharmacological mechanisms of ML on metabolic diseases have not been fully revealed. Therefore, in order to fully utilize and scale relevant products about ML, this review summarizes the up-to-date information about the ML and its constituents effecting on metabolic disease.

Plant Extracts in Obesity: A Role of Gut Microbiota

Obesity has become one of the most serious chronic diseases threatening human health. Its occurrence and development are closely associated with gut microbiota since the disorders of gut microbiota can promote endotoxin production and induce inflammatory response. Recently, numerous plant extracts have been proven to mitigate lipid dysmetabolism and obesity syndrome by regulating the abundance and composition of gut microbiota. In this review, we summarize the potential roles of different plant extracts including mulberry leaf extract, policosanol, cortex moutan, green tea, honokiol, and capsaicin in regulating obesity via gut microbiota. Based on the current findings, plant extracts may be promising agents for the prevention and treatment of obesity and its related metabolic diseases, and the mechanisms might be associated with gut microbiota.

Differential Metabolomics and Network Pharmacology Analysis of Silkworm Biotransformation between Mulberry Leaves and Silkworm Droppings

Silkworm droppings are the product of mulberry leaves digested by silkworm intestines, which are an important medicinal resource in traditional Chinese medicine (TCM). The contents of total fat, fat acids, crude protein, amino acids, and secondary metabolites of obtained mulberry leaves and silkworm droppings were analyzed by HPLC, GC-MS, and UHPLC-Q-TOF MS. The target genes and enriched pathways related to significantly changed compositions between mulberry leaves and silkworm droppings were analyzed by network pharmacology. High unsaturated C18 : 3 fatty acids were transformed to low unsaturated C18 : 1 from mulberry leaves to silkworm droppings. Only lysine and 17 mini-peptides had significantly higher content in silkworm droppings than in mulberry leaves. There were 36 common target genes or the different compounds between mulberry leaves and silkworm droppings. The main pathways of mulberry leaf were enriched in antivirus and anticancer properties, while the pathways of silkworm droppings were enriched in hormone regulation and signal transduction.

Mulberry leaf powder regulates antioxidative capacity and lipid metabolism in finishing pigs

This study evaluated the potential of mulberry leaf powder as an unconventional feed material for finishing pigs by assessing the growth performance, antioxidative properties, fatty acid profile, and lipid metabolism in 180 Xiangcun black pigs. Pigs with an initial body weight (BW) of 71.64 ± 1.46 kg were randomly assigned to 5 treatment groups, including the control diet and 4 experimental diets. The corn, soybean meal, and wheat bran in the control diet were partly replaced by 3%, 6%, 9%, or 12% mulberry leaf powder in experimental diets. There were 6 replicates (pens) of 6 pigs per replicate in each treatment. Blood and muscle samples were collected after the 50-day feed experiment. Compared with the control group, the 3%, 6%, and 9% mulberry diets had no adverse effect (P > 0.05) on the growth performance of pigs. The serum glutathione peroxidase activity and glutathione concentration increased linearly (P < 0.05) with the increase in dietary mulberry inclusion. There was no significant difference in the relative expression levels of antioxidant-related genes in muscle tissue between the control and mulberry groups. Inclusion of dietary mulberry powder increased (P < 0.05) the content of polyunsaturated fatty acids, especially in the longissimus dorsi (LD) muscle, up-regulated (P < 0.05) the relative mRNA expression level of uncoupling protein-3 in muscle tissue, but down-regulated (P < 0.05) the relative mRNA expression levels of hormone-sensitive lipase, acetyl CoA carboxylase α, lipoprotein lipase, and peroxisome proliferator-activated receptor γ in LD in a linear pattern. The nuclear respiratory factor 2 expression level in the LD muscle of pigs fed the 9% mulberry diet was higher (P < 0.01) than that in the other mulberry groups and control group. The inclusion of less than 12% dietary mulberry did not detrimentally affect the growth performance of Xiangcun black pigs, but enhanced the serum antioxidant property, increased the polyunsaturated fatty acid content, and inhibited lipid oxidation by regulating gene expression levels of lipid metabolism and mitochondrial uncoupling protein in muscle tissue. Mulberry leaves can be utilized as a forage crop in the diet of finishing pigs.

Hypolipidemic and Antioxidant Activities of Corrigiola telephiifolia in Diabetic Rats

Objective:

The evaluation of the hypolipidemic and antioxidant activities of the aerial parts aqueous extract of Corrigiola telephiifolia (APAE of C. telephiifolia) in normal and streptozotocin (STZ)-induced diabetic rats.

Methods:

The effects of oral administration of APAE of C. telephiifolia (5 mg/kg) on the lipid profile as well as the in vitro antioxidant activity of this aqueous extract have been determined.

Results:

APAE of C. telephiifolia (5 mg/kg) reduced significantly (p<0.001) the plasma total cholesterol levels in diabetic rats. In contrast, no significant increase in plasma triglyceride levels in normal and in STZ-induced diabetic rats was observed. On the other hand, APAE of C. telephiifolia showed an antioxidant activity.

Conclusion:

The APAE of C. telephiifolia exhibits an antioxidant, cholesterol and body weight-lowering activities in diabetic rats.

Differential effects of red yeast rice, Berberis aristata and Morus alba extracts on PCSK9 and LDL uptake

BACKGROUND AND AIMS

The novel nutraceutical combination containing red yeast rice (monacolin K 3.3 mg), Berberis aristata cortex extract (Berberine 531.25 mg) and Morus alba leaves extract (1-deoxynojirimycin 4 mg) is effective in the management of elevated plasma low-density lipoprotein cholesterol (LDL-C) levels. The aim of the present study was to investigate the effects of the three components on proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of LDL receptor (LDLR) expression, in hepatocyte cell lines and to compare their effects on LDL cellular uptake.

METHODS AND RESULTS

HepG2 and Huh7 cells were incubated with B. aristata cortex extract (BCE), red yeast rice (RYR) and M. alba leaves extract (MLE) alone or in combination for 24 h. RYR (50 μg/mL) increased PCSK9 protein expression (Western blot analysis and ELISA), PCSK9 mRNA (qPCR) and its promoter activity (luciferase reporter assay). BCE (40 μg/mL) reduced instead PCSK9 expression, mRNA levels and promoter activity. MLE determined a concentration-dependent reduction of PCSK9 at the mRNA and protein levels, with a maximal reduction at 1 mg/mL, without significant changes of PCSK9 promoter activity. MLE also downregulated the expression of 3-hydroxy-3-methyl-3-glutaryl coenzyme A reductase and fatty acid synthase mRNA levels. The combination of RYR, BCE and MLE reduced the PCSK9 mRNA and protein levels, as well as the promoter activity. Finally, the single components and their combination induced LDL receptor and LDL uptake by the hepatocytes.

CONCLUSION

The positive effect of MLE on PCSK9 supports the rationale of using the nutraceutical combination of RYR, BCE and MLE to control hyperlipidemic conditions.

Bioefficacy of red cabbage against hypercholesterolemic diet mediated oxidative stress

Background

The shift towards hypercaloric diets and sedentariness has raised lifestyle related disorders and escalated health care cost. In order to tackle this epidemiological transition, healthy, affordable food choices should be introduced in the routine menu. In this context, red cabbage is known for its rich phytochemistry, minerals, antioxidant vitamins and dietary fiber. Considering these evidences, red cabbage leaves and its extract were assessed against hypercholesterolemia and associated oxidative stress.

Methods

In bioefficacy assessment trial (12 weeks), there were two dietary regimens; normal and hypercholesterolemic (1% cholesterol) that were further split into three groups each. In both feeding trials, red cabbage leaves (20%) and its extract in dose equivalent to red cabbage leaves were assessed against control diets. At termination of trial, serum lipidemic parameters and oxidative stress biomarkers were assessed to test the efficacy of diets.

Results

In hypercholesterolemic rabbits, red cabbage leaves showed significant reduction in cholesterol, LDL-c and triacylglycerol levels i.e. 15.19, 18.09 and 9.42% than extract administered groups; 10.79, 12.24 and 5.72, respectively. Besides, red cabbage leaves also portrayed momentous enhancement of superoxide dismutase (SOD) and catalase (CAT) activity up to 13.29 & 17.63% by lowering lipid peroxidation by 27.86% in hypercholesterolemic diet fed groups, whereas red cabbage extract administered group depicted relatively lesser amelioration in lipid peroxidation i.e. 21.42%.

Conclusions

Red cabbage leaves possess higher ameliorative potential against altered lipidemic profile and lipid peroxidation as compared to its extract thus explains its ability to prevent exhaustion of endogenous antioxidant enzymes; SOD and CAT.

Mulberry leaves and their potential effects against cardiometabolic risks: a review of chemical compositions, biological properties and clinical efficacy

CONTEXT

Cardiometabolic risks are regarded as the crucial factors associated with type 2 diabetes (T2DM) and cardiovascular diseases (CVD). Regarding an increased attention to medicinal plants in the current healthcare system, the effects of mulberry (Morus spp., Moraceae) leaves on cardiometabolic risks have been consecutively considered in scientific research.

OBJECTIVE

The present review compiles and summarizes the chemical compositions, biological properties and clinical efficacy of mulberry leaves that are related to the amelioration of cardiometabolic risks.

METHODS

Published English literature from the PubMed, Science Direct and Google Scholar databases was searched by using 'mulberry leaves' 'Morus spp.', 'hyperglycemia', 'hyperlipidemia', 'obesity', 'hypertension', 'oxidative stress', 'atherosclerosis' and 'cardiovascular diseases' as the keywords. The relevant articles published over the past two decades were identified and reviewed.

RESULTS

Mulberry leaves contain numerous chemical constituents. 1-Deoxynojirimycin (DNJ), phenolics and flavonoids are the prominent functional compounds. Preclinical and clinical studies showed that mulberry leaves possessed various beneficial effects against cardiometabolic risks, including antihyperglycaemic, antihyperlipidaemic, antiobesity, antihypertensive, antioxidative, anti-inflammatory, anti-atherosclerotic and cardioprotective effects.

CONCLUSIONS

Mulberry leaves could be a promising therapeutic option for modulating cardiometabolic risks. However, further investigations should be performed to substantiate the potential of mulberry leaves in practical uses.

Effect of different planting areas on the chemical compositions and hypoglycemic and antioxidant activities of mulberry leaf extracts in Southern China

Guangdong, Guangxi and Chongqing are emerging sericulture areas in China where the production of mulberry leaves is huge. In order to identity high quality mulberry leaves that are suitable for healthy products to expand planting, 24 samples from three regions (Guangdong, Guangxi, Chongqing) in the south of China were quantified for two alkaloids (1-deoxynojirimycin and fagomine) and five phenols (chlorogenic acid, rutin, isoquercitrin, etc.) using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Additionally, the total phenolic and total flavonoid contents, antioxidant and glycosidase inhibitory activities (hypoglycemic activity) were tested using different assays (DPPH, ABTS, FRAP) to comprehensively evaluate the quality of the mulberry leaves. The contents of DNJ and fagomine ranged from 0.401±0.003 to 5.309±0.036 mg/g and from 0.279±0.031 to 2.300±0.060 mg/g, respectively. The main phenolic constituents were chlorogenic acid, rutin and isoquercitrin, with chlorogenic acid present in the highest concentrations, ranging from 3.104±0.191 to 10.050±0.143 mg/g. The antioxidant activity exhibited a tendency as follows: Guangxi > Guangdong > Chongqing, except for two samples from Chongqing, which showed the highest antioxidant activity. Based on our study, mulberry leaves from Guangdong and Guangxi could be future sources of natural hypoglycemic and antioxidant products.

Effects of mulberry leaf on experimental hyperlipidemia rats induced by high-fat diet

Hypercholesterolemia is a major risk factor for cardiovascular disease. Mulberry leaf (ML) is a Traditional Chinese Medicine used to treat hyperlipidemia in clinical settings. The aim of the present study was to identify the potential effect and possible target of ML in anti-hypercholesterolemia. Male Sprague-Dawley rats were fed with a high-fat diet and treated with ML for 5 weeks. Blood lipid levels, total cholesterol (TC) and total bile acid (TBA) in the liver and feces were measured to assess the effects of ML on hypercholesterolemia. Harris's hematoxylin staining and oil red O staining was applied to observe the pathological change and lipid accumulation in the liver. Immunohistochemical assay was performed to observe the location of expressions of scavenger receptor class B type I and low-density lipoprotein (LDL) receptor (-R), and western blotting was applied to determine the protein expression of ATP-binding cassette transporter G5/G8 (ABCG5/8), nuclear transcription factor peroxisome proliferator-activated receptor-α (PPARα), farnesoid-X receptor (FXR) and cholesterol 7α-hydroxylase 1 (CYP7A1). The results demonstrated that ML treatment reduced serum TC and LDL-cholesterol levels, and liver TC and TBA contents; increased serum HDL-C levels, and fecal TC and TBA contents; and alleviated hepatocyte lipid degeneration. In addition, ML treatment inhibited liver LDL-R, PPARα and FXR protein expression, promoted protein expression of CYP7A1, and maintained the ratio of ABCG5/ABCG8. The findings of the present study provide a positive role of ML on cholesterol clearance via promoting cholesterol and TBA execration via FXR- and CYP7A1-mediated pathways; RCT regulation may be a potential mechanism of ML on anti-hypercholesterolemia.

Thermal and Antioxidant Properties of Polysaccharides Sequentially Extracted from Mulberry Leaves (Morus alba L.)

Polysaccharides from natural plant products are gaining considerable attention due to their multi-faceted health effects, as well their functional applications in food production. We reported the sequential extraction of mulberry leaf polysaccharides (MLPs) with hot buffer (HBSS), chelating agent (CHSS), dilute alkali (DASS) and concentrated alkali (CASS), in order to obtain polysaccharide fractions. Monosaccharide analysis proved that galactose (27.07%) and arabinose (25.99%) were the major sugars in HBSS, whereas arabinose (30.55%) was the major sugar in CHSS, and glucose was the major sugar in DASS (24.96%) and CASS (27.51%). The molecular weights of the polysaccharide fractions were 7.812 × 10³ (HBSS), 3.279 × 10³ (CHSS), 6.912 × 10³ (DASS), and 1.408 × 10³ kDa (CASS). HBSS and CASS showed the largest peak temperature and the highest endothermic enthalpy, respectively. Different antioxidant assays showed that the MLPs possessed appreciable antioxidant activities in a dose-dependent manner. At 5 mg/mL, HBSS and DASS possessed the largest 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging activity (96.82%). HBSS exhibited the highest reducing power, and DASS rendered the strongest ABTS radical scavenging activity (99.69%). CHSS performed the best hydroxyl radical scavenging activity (64.22%) and Fe²⁺-chelating ability (96.36%). Our results suggested that MLPs could be a promising source of natural antioxidants for use in the food, pharmaceutical, and cosmetic industries.

Effect of mulberry leaf (Folium Mori) on insulin resistance via IRS-1/PI3K/Glut-4 signalling pathway in type 2 diabetes mellitus rats

CONTEXT

Folium Mori, the leaf of Morus alba L. (Moraceae), has been used in traditional Chinese medicine (TCM) for treating diabetes. However, it is unclear which components in the mulberry leaf are effective for the treatment of type 2 diabetes mellitus (T2DM).

OBJECTIVE

To investigate the flavonoids and polyphenols in mulberry leaves and their antihyperglycemic and antihyperlipidemic effects in T2DM rats.

MATERIALS AND METHODS

Male Sprague-Dawley rats were divided into five groups: normal control (NC), diabetic control (DBC), diabetic group with 0.3 mg/kg b.w./day rosiglitazone (RSG), diabetic group with 7 g/kg b.w./day TCM formula and diabetic group with 2 g/kg b.w./day Folium Mori extract (FME). After 4 weeks, the rats were sacrificed; biochemical parameters, gene and protein expression were measured.

RESULTS

The FBG level was significantly lower in the FME group than in the DBC group (p < 0.05). In oral glucose tolerance test, the AUC was significantly lower in the FME group (p < 0.05). The HOMA-IR level was significantly decreased in the FME group (p < 0.05). FME decreased the total cholesterol (TC), triglyceride (TG) and low density lipoprotein (LDL) levels (p < 0.05). FME increased the mRNA and protein expression of IRS-1, PI3K p85α and Glut-4 increased significantly (p < 0.05). Histological analysis revealed amelioration of lipid accumulation following FME treatment. Additionally, immunohistochemical analysis displayed stronger staining of Glut-4 in the FME group compared to the DBC group.

DISCUSSION AND CONCLUSION

FME could decrease the body weight, blood glucose, TG, TC and LDL levels, and improve insulin resistance. FME possessed significant antihyperglycemic and antihyperlipidemic activities via the IRS-1/PI3K/Glut-4 signalling pathway.

Anti-atherosclerotic plants which modulate the phenotype of vascular smooth muscle cells

BACKGROUND

Cardiovascular disease (CVD) remains the leading cause of global death, with atherosclerosis being a major contributor to this mortality. Several mechanisms are implicated in the pathogenesis of this disease. A key element in the development and progression of atherosclerotic lesions is the phenotype of vascular smooth muscle cells. Under pathophysiologic conditions such as injury, these cells switch from a contractile to a synthetic phenotype that often possesses high proliferative and migratory capacities.

PURPOSE

Despite major advances made in the management and treatment of atherosclerosis, mortality associated with this disease remains high. This mandates that other approaches be sought. Herbal medicine, especially for the treatment of CVD, has been gaining more attention in recent years. This is in no small part due to the evidence-based values associated with the consumption of many plants as well as the relatively cheaper prices, easier access and conventional folk medicine "inherited" over generations. Sections: In this review, we provide a brief introduction about the pathogenesis of atherosclerosis then we highlight the role of vascular smooth muscle cells in this disease, especially when a phenotypic switch of these cells arises. We then thoroughly discuss the various plants that show potentially beneficial effects as anti-atherosclerotic, with prime attention given to herbs and plants that inhibit the phenotypic switch of vascular smooth muscle cells.

CONCLUSION

Accumulating evidence provides the justification for the use of botanicals in the treatment or prevention of atherosclerosis. However, further studies, especially clinical ones, are warranted to better define several pharmacological parameters of these herbs, such as toxicity, tolerability, and efficacy.

The Prokinetic, Laxative, and Antidiarrheal Effects of Morus nigra: Possible Muscarinic, Ca(2+) Channel Blocking, and Antimuscarinic Mechanisms

Morus nigra Linn. (black mulberry) is used in gastrointestinal ailments. This study demonstrates gut modulatory properties of M. nigra. The prokinetic, laxative, and antidiarrheal activities of M. nigra were assessed in mice, while isolated rabbit jejunum and guinea-pig ileum were used to explore insight into mechanism(s). At 30 and 70 mg/kg, the crude extract of M. nigra (Mn.Cr) exhibited atropine-sensitive prokinetic and laxative effects, similar to carbachol (CCh). While at higher doses (100, 300, and 500 mg/kg), Mn.Cr offered protection against castor oil-induced diarrhea. In rabbit jejunum, Mn.Cr and its chloroform fraction inhibited CCh-induced contractions more potently compared with high K(+) (80 mm). Conversely, petroleum fraction was more potent against high-K(+) -induced contractions. At 0.01 mg/mL, Mn.Cr caused a parallel shift in acetylcholine concentration-response curves (CRCs) followed by a non-parallel shift at 0.03 mg/mL, similar to dicyclomine. At further tested concentrations, Mn.Cr (0.1 and 0.3 mg/mL) and petroleum fraction suppressed Ca(2+) CRCs, similar to verapamil. In guinea-pig ileum, Mn.Cr, its aqueous and ethyl acetate fractions exhibited atropine-sensitive gut stimulant activity along with additional uncharacterized excitatory response in the aqueous fraction only. These results suggest that black mulberry possesses prokinetic, laxative, and antidiarrheal effects, putatively mediated through cholinomimetic, antimuscarinic, and Ca(2+) antagonist mechanisms, respectively. Copyright © 2016 John Wiley & Sons, Ltd.

In vitro and In vivo Antioxidant Activity of Flavonoid Extracted from Mulberry Fruit (Morus alba L.)

Background:

Many plants possess antioxidants that exhibit additive or synergistic activities.

Objective:

In this study, an ethanol-extracted flavonoid extracted from mulberry fruit (FEM) was evaluated for the antioxidant activity in vitro and the hemolysis in red blood cell (RBC) and lipid peroxidation in liver in vivo.

Materials and Methods:

Antioxidant activities in vitro were measured by quantifying its 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, reducing power, and Fe²⁺-chelating ability. FEM inhibits hemolysis in RBCs and effects of lipid peroxidation in the liver were estimated.

Results:

The total content of flavonoid compounds was 187.23 mg of quercetin equivalents per grams dried material. In the in vitro assays, FEM demonstrated a strong antioxidant effect, especially in DPPH scavenging activity and reducing power. Mouse RBC hemolysis induced by H₂O₂ was significantly inhibited by FEM in a dose- and time-dependent manner. The effects of FEM on lipid peroxidation in liver, mitochondria, and microsome were investigated. The percentage of inhibition at high concentration (100 μg/mL) of FEM was 45.51%, 39.36%, and 42.78% for liver, mitochondria, and microsomes, respectively. These results suggest that the FEM possesses a strong antioxidant activity both in vivo and in vitro.

SUMMARY

The total content of flavonoid compounds in mulberry fruit was 187.23 mg/g dried material

FEM showed a strong antioxidant effect, especially in 2,2-diphenyl-1-picrylhydrazyl scavenging activity and reducing power

Mouse red blood cell hemolysis induced by H₂O₂ was significantly inhibited by FEM in a dose- and time-dependent manner

The inhibition percentage at high concentration of FEM was 45.51%, 39.36%, and 42.78% for mouse’s liver, mitochondrial, and microsomes, respectively.

Abbreviations used: FEM: Flavonoid Extracted from Mulberry fruit, H₂O₂: Hydrogen peroxide, DPPH: 2,2-diphenyl-1-picrylhydrazyl, EDTA: Ethylene diamine tetraacetic acid, MDA: malondialdehyde, TBA: 2-thiobarbituric acid, RBC: Red blood cells, DNJ: 1-deoxynojirimycin, LDL: low density lipoprotein, ROS: reactive oxygen species, EDTA2Na: Ethylenediaminetetraacetic acid disodium salt.

Identification and Determination of the Polyhydroxylated Alkaloids Compounds with α-Glucosidase Inhibitor Activity in Mulberry Leaves of Different Origins

Mulberry leaves have commonly been utilized in China as a herbal medicine for the treatment of diabetes for thousands of years. To evaluate the quality, an ultra-high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS) method was developed for identification of polyhydroxylated alkaloids with α-glucosidase inhibitor activity in mulberry leaf. As a result, five alkaloid compounds were identified or tentatively characterized. Among them, the compound 1-deoxynojirimycin (DNJ) was selected as the most typical and active chemical marker and quantified using an improved high performance liquid chromatography (HPLC) normal phase coupled with evaporative light scattering detector (ELSD) method. The developed method was fully validated in terms of linearity, sensitivity, precision and repeatability, as well as recovery, and subsequently applied to evaluate twenty-nine batches of mulberry leaves from different collections. From the analytical data it was discovered that the average content of DNJ is 1.53 mg/g, while the total contents of DNJ in the 29 mulberry leaf sample ranged from 0.20 to 3.88 mg/g, which suggested remarkable differences, although it reached the highest levels in early August. These data may provide an important reference for the quality of mulberry leaves used as herbal medicine for the treatment of diabetes or as a material to obtain the DNJ of α-glucosidase inhibitor or as a functional food.

Reduction of post-prandial hyperglycemia by mulberry tea in type-2 diabetes patients

AIM

The dietary contents have a very important role in the management of metabolic syndrome along with type 2 diabetes mellitus (T2DM). Indian diet contains a large amount of carbohydrates that set off unpredictable blood sugar fluctuations and leads to increased risk of diabetic complications. The aim of the present study was to identify the effect of mulberry tea in the reduction of abnormally high postprandial blood glucose (PPG) levels in T2DM patients.

METHODS

The study design was follow-up T2DM, 20 diabetic patients were given plain tea (control) and 28 diabetic patients were given mulberry tea (test subject) to measure the effect of mulberry tea on fasting blood glucose and PPG levels. Fasting blood glucose samples were collected after a standard breakfast. The PPG levels were recorded after the consumption of 70 ml tea along with 1 teaspoon of sugar after 90 min in all 48 patients.

RESULTS

Fasting blood glucose levels in control and test group samples were found to be 178.55 ± 35.61 and 153.50 ± 48.10, respectively. After the consumption of plain tea and mulberry tea, the PPG values were recorded as 287.20 ± 56.37 and 210.21 ± 58.73, respectively. A highly significant (p < 0.001) change in the PPG level was observed in response to mulberry tea in all the test patients compared with control. Moreover, the effect size was also found to be very large (1.31).

CONCLUSION

Mulberry tea suppresses postprandial rise of blood glucose levels after 90 min of its consumption.

Mulberry leaf polyphenols delay aging and regulate fat metabolism via the germline signaling pathway in Caenorhabditis elegans

Mulberry leaves are an important ingredient in some traditional Chinese medicinal formulas and has been developed for use in functional food products. The antioxidant activity of mulberry leaf extract has been reported to have beneficial effects on diseases in vitro; however, it is not clear which components in mulberry leaf extracts have these functions. Furthermore, the mechanisms of action of these ingredients have not been extensively investigated. In this study, we extracted total mulberry leaf polyphenols (MLP) and identified its 13 phenolic monomers. Our results, using Caenorhabditis elegans as a model, indicated that MLPs delayed aging, improved oxidative stress resistance, and reduced fatty acid storage in vivo. Subsequent genetic screens and gene expression analyses demonstrated that the functions of MLP mainly depended on the germline signaling pathway, thus influencing the activities of downstream transcription factors (DAF-12, DAF-16, PHA-4, and NHR-80) as well as the expression levels of their target genes (fat-6, lipl-4, sod-3, unc-51, and fard-1). Our study determined that diverse modes of action on longevity were promoted by MLP exposure. These observations provide the first insight into MLP's multifaceted functions on aging, fat accumulation, and reproduction in vivo and indicate a specific model for the mechanism of action of MLP. This is a significant finding that lends support to the hypotheses that mulberry leaf extracts can have an impact on human health.