Hypoglycemic effect of water-soluble polysaccharide from Auricularia auricula-judae Quel. on genetically diabetic KK-Ay mice

Mushrooms and Fungi and Their Biological Compounds with Antidiabetic Activity: A Review

Mushrooms have been used by humans for centuries as food and medicine because they have been shown to affect certain diseases. Mushrooms for medicinal purposes have been consumed in the form of extracts and/or biomass of the mycelium or fruiting body. The beneficial health effects of mushrooms are due to their content of bioactive compounds (polysaccharides, proteins, ergosterol, lectins, etc.). On the other hand, diabetes is one of the metabolic diseases that affects the population worldwide, characterized by hyperglycemia that involves a defective metabolism of insulin, a hormone secreted by β cells and that mainly stimulates glucose absorption by the cells. However, it also affects the metabolism of carbohydrates, fats and proteins; poor control of this disease leads to serious damage to eyesight, kidneys, bones, heart, skin, blood vessels, nerves, etc. It has been reported that the consumption of some mushrooms helps control and treat diabetes, since among other actions, they promote the secretion of insulin by the pancreas, help reduce blood glucose and have α-glucosidase inhibitory activity which improves glucose uptake by cells, which are effects that prescription medications have for patients with diabetes. In that sense, this manuscript shows a review of scientific studies that support the abilities of some mushrooms to be used in the control and/or treatment of diabetes.

Polysaccharides from fungi: A review on their extraction, purification, structural features, and biological activities

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A variety of extraction methods of polysaccharides from fungi are reviewed and compared.

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Purification methods, structure of fungal polysaccharides were reviewed.

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Diverse biological activities of fungal polysaccharides were outlined.

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Structure-activity relationships of fungal polysaccharides were discussed.

Fungi, as the unique natural resource, are rich in polysaccharides, proteins, fats, vitamins, and other components. Therefore, they have good medical and nutritional values. Polysaccharides are considered one of the most important bioactive components in fungi. Increasing researches have confirmed that fungal polysaccharides have various biological activities, such as antioxidant, immunomodulatory, anti-tumor, hepatoprotective, anti-aging, anti-inflammatory, and radioprotective activities. Consequently, the research progresses and future prospects of fungal polysaccharides must be systematically reviewed to promote their better understanding. This paper reviewed the extraction, purification, structure, biological activity, and underlying molecular mechanisms of fungal polysaccharides. Moreover, the structure–activity relationships of fungal polysaccharides were emphasized and discussed. This review can provide scientific basis for the research and industrial utilization of fungal polysaccharides.

Neutral Polysaccharides From Hohenbuehelia serotina With Hypoglycemic Effects in a Type 2 Diabetic Mouse Model

Neutral polysaccharides (NHSPs) from the mushroom Hohenbueheliaserotina were purified by D301/D152 resin ion-exchange chromatography and DEAE-cellulose anion exchange chromatography. The weight-average molecular weight (M_W) and number-average molecular weight (Mn) of NHSP were 1,821 and 820.55 kDa, respectively. A monosaccharide component analysis showed that NHSP was composed of glucose, galactose, and mannose in molar ratio 2.6:2.1:1.0. FT-IR and NMR (¹H and HSQC) spectroscopic analyses revealed that NHSP contained mainly 1,3-linked β-D-glucose, 1,4-linked β-D-glucose, 1,6-linked β-D-mannose, 1,6-linked α-D-mannose, and 1,6-linked β-D-galactose. The thermogravimetric analysis (TGA) showed that NHSP has good thermal stability below 250°C. NHSP notably reduced the blood glucose level (hypoglycemic effect) at dose 200 mg/kg for 21 days in a type 2 diabetic mouse model. NHSP reduced the liver index significantly, suggesting that it may help prevent hepatic steatosis or hepatomegaly.

Skin Wound-Healing Potential of Polysaccharides from Medicinal Mushroom Auricularia auricula-judae (Bull.)

Auricularia auricula-judae, a nutrient-rich mushroom used in traditional medicine, is a macrofungi that exhibits various biological properties. In this study, we have reported on the mechanisms that promote the wound-healing effects of a water-soluble polysaccharide-rich extract obtained from A. auricula-judae (AAP). AAP contained high amounts of polysaccharides (349.83 ± 5.00 mg/g extract) with a molecular weight of 158 kDa. The main sugar composition of AAP includes mannose, galactose, and glucose. AAP displayed antioxidant activity in vitro and was able to abort UVB-induced intracellular ROS production in human fibroblasts in cellulo. AAP significantly promoted both fibroblast and keratinocyte proliferation, migration, and invasion, along with augmentation of the wound-healing process by increasing collagen synthesis and decreasing E-cadherin expression (All p < 0.05). Specifically, the AAP significantly accelerated the wound closure in a mice skin wound-healing model on day 9 (2.5%AAP, p = 0.031 vs. control) and day 12 (1% and 2.5%AAP with p = 0.009 and p < 0.001 vs. control, respectively). Overall, our results indicate that the wound-healing activities of AAP can be applied in an AAP-based product for wound management.

Review on Auricularia auricula-judae as a Functional Food: Growth, Chemical Composition, and Biological Activities

Although the application of Auricularia auricula-judae (AAJ) for health purposes has a long tradition in Asia, there is a lack of research on the functional nutrition of AAJ; the current research focused on polysaccharides has been too unitary compared to other mushrooms in recent years. Identification, extraction, and large-scale production of biologically active substances have emerged as critical determinants that determine AAJ becoming a functional food. AAJ is being treated in a restrained manner, despite having significant potential as a drug or a source of pure bioactive substances. Functional ingredients of mushrooms and AAJ have emerged as a new impetus for researchers interested in developing functional foods. This review presents an overview of current studies relevant to nutrition and the application of AAJ. The physiological conditions of AAJ and the corresponding functional ingredients beneficial to human health are reviewed to better understand the function and mechanisms of different nutrient contents. Relevant methods for evaluating the efficiency of extraction are also summarized. Finally, current limitations and the future scope for functional ingredients of AAJ are identified and discussed.

Phagocytosis enhancement, endotoxin tolerance, and signal mechanisms of immunologically active glucuronoxylomannan from Auricularia auricula-judae

Glucuronoxylomannan (AAPS) from the edible wood ear mushroom Auricularia auricula-judae has been demonstrated to exhibit immunostimulatory properties through its binding to TLR4. However, the mechanisms of immune modulation by AAPS in mammalian cells remains unclear. In the present study, we demonstrated that AAPS induced immunostimulatory effects were regulated by reactive oxygen species, mitogen-activated protein kinases, protein kinase C-α and NF-κB. AAPS remarkably increased the phagocytosis and bactericidal activity of macrophages. In lipopolysaccharide-activated macrophages, AAPS induced endotoxin tolerance like effect characterized by the downregulation of nitric oxide, interleukin-6 and TNF-α via the downregulation of NF-κB activation. Our findings provide firm scientific evidences for the immunoenhancing properties of wood ear mushroom, and the potential of AAPS to be strong candidates for the development of new carbohydrate-based nutraceutical supplements in the management of immunity related disorders in the future.

Ultrasonic-assisted extraction of polysaccharides from Auricularia auricula and effects of its acid hydrolysate on the biological function of Caenorhabditis elegans

The present study was designed to explore the in vivo-antioxidant capacity and the probable mechanism of AAPs-H, prepared from Auricularia auricula polysaccharides with the optimal extraction conditions by Box-Behnken design and acid hydrolysis, using Caenorhabditis elegans as a model organism. The effects of AAPs-H on the locomotion behavior, life span, antioxidant-related enzymes activities, and antioxidants levels in C. elegans were studied. Furthermore, the potentials of AAPs-H in up-regulating the expression of antioxidant-related genes in C. elegans, such as skn-1, sod-3 and sir-2.1, were also discussed. AAPs-H demonstrated a highly significant protective effect against the damage caused by paraquat, could significantly increase U-Turn frequency of worms (p < 0.01), extend their lifespan, enhance antioxidant systems including GR by 63.96% (p < 0.05), GSH-Px by 71.16% (p < 0.01), SOD by 78.65% (p < 0.01) and CAT by 98.52% (p < 0.01), increase the level of GSH by 28.12% (p < 0.05), and decrease the level of MDA by 39.29% (p < 0.01). The qRT-PCR results showed that AAPs-H could up regulate mRNA expression levels of skn-1, sod-1, sod-2, sod-3 and sir-2.1 in wild-type C. elegans (>1.6 fold) when treated with the concentration of 0.4 mg/mL (p < 0.05 or p < 0.01). Our studies provide evidence that AAPs-H improves antioxidant defense system, and up-regulation of oxidative stress related genes for prevention of stress damage in C. elegans.

Antidiabetic effect of Equisetum giganteum L. extract on alloxan-diabetic rabbit

ETHNOPHARMACOLOGICAL RELEVANCE

Equisetum giganteum has been traditionally used as an anti-diabetic herbal remedy to treat diabetes in the southern state of Rio Grande do Sul in Brazil.

AIM OF THE STUDY

Considering the ethonopharmacology and historical importance of E. giganteum, its potential antidiabetic effect was evaluated in alloxan induced diabetic rabbits.

MATERIAL AND METHODS

Samples of Equisetum giganteum were collected in the city of Ouro Preto, Minas Gerais, Brazil. Butanolic and aqueous extracts were prepared and subsequently evaluated for anti-diabetic properties in vivo using albino male rabbits. At the end of the treatment period, the animals were euthanized, and histopathological analysis were carried out. The following biochemical parameters were studied: glucose, triacylglycerol, cholesterol, albumin, creatinine, glycosylated hemoglobin and lipase. The phytochemical profile of the extracts was studied by liquid chromatography techniques coupled to a UV/VIS detector and high-resolution mass spectrometry.

RESULTS

Both aqueous and butanolic extracts were capable of reducing significantly the levels of glucose, cholesterol and triacylglycerol and thus demonstrating their hypolipidemic and hypoglycemiant effects. Furthermore, the extracts prevented the occurrence of hepatic complications during treatment. The phytochemical profile of the extracts was investigated, and the natural products detected were in agreement with those that had been previously described in the literature.

CONCLUSION

Based on the significant reductions in biochemical parameters and the histologic evidence for the absence of complications in the liver, pancreas of the treated animals, Equisetum giganteum can be a therapeutically relevant resource in the treatment of diabetes and hyperlipidemia.

Antidiabetic Effects of the Auricularia auricular Polysaccharides Simulated Hydrolysates in Experimental Type-2 Diabetic Rats

A model of type-2 diabetes mellitus (T2DM) using high-fat diet and low-dose STZ was established to assess the antidiabetic effects of Auricularia auricular polysaccharides simulated hydrolysates (AAPHs) obtained from the dried fruiting body of A. auricular. AAPHs were administered intragastrically (i.g.) at the dose of 0.15 g/kg b. W. to diabetic Wistar rats for 4 weeks. Results show that AAPHs was demonstrated to exhibit significant diminution in T-CHO and LDL-C levels (P < 0.05 or P < 0.01) compared to the diabetic control group. In addition, the secretion level of GLP-1 were different with the diabetes model group from 0 to 30 min, and had a tendency to alleviate weight loss. The current study suggests that AAPHs might be incorporated as a supplement in diabetic agents or combined with other health-care foods.

Starch Hydrolysis, Polyphenol Contents, and In Vitro Alpha Amylase Inhibitory Properties of Some Nigerian Foods As Affected by Cooking

The effect of cooking on starch hydrolysis, polyphenol contents, and in vitro α-amylase inhibitory properties of mushrooms (two varieties Russula virescens and Auricularia auricula-judae), sweet potato (Ipomea batatas), and potato (Solanum tuberosum) was investigated. The total, resistant, and digestible starch contents of the raw and cooked food samples (FS) ranged from 6.4 to 64.9; 0 to 10.1; and 6.4 to 62.7 g/100 g, respectively, while their percentages of starch digestibility (DS values expressed as percentages of total starch hydrolyzed) ranged from 45.99 to 100. Raw and boiled unpeeled potato, raw and boiled peeled potato, raw A. auricula-judae, and sweet potato showed mild to high α-amylase inhibition (over a range of concentration of 10-50 mg/mL), which was lower than that of acarbose (that had 69% inhibition of α-amylase over a range of concentration of 2-10 mg/mL), unlike raw R. virescens, boiled A. auricula-judae, and boiled sweet potatoes that activated α-amylase and boiled R. virescens that gave 0% inhibition. The FS contained flavonoids and phenols in addition. The significant negative correlation (r = -0.55; P = 0.05) between the α-amylase inhibitory properties of the raw and cooked FS versus their SD indicates that the α-amylase inhibitors in these FS also influenced the digestibility of their starches. In addition, the significant positive correlation between the α-amylase inhibitory properties of the raw and cooked FS versus their resistant starch (RS) (r = 0.59; P = 0.01) contents indicates that the RS constituents of these FS contributed to their α-amylase inhibitory properties. The study showed the usefulness of boiled unpeeled potato, boiled potato peeled, and raw sweet potato as functional foods for people with type 2 diabetes.

Synergistic rheological behavior and morphology of yam starch and Auricularia auricula-judae polysaccharide-composite gels under processing conditions

Polysaccharides from Auricularia auricula-judae (AP) have unique functionalities. The influence of AP-blending ratios (0.1-0.8%), temperature, pH, and ionic strength on the rheological interactions of yam starch (YS)-AP blends (YA, 6%) was investigated. YA gels showed shear-thinning behavior with flow-behavior indices of 0.28-0.37 and greater pseudoplasticity in the presence of 0.8% AP. With incremental AP addition, the viscosity and consistency indices significantly increased, whereas the activation energy decreased from 7.55 to 5.12 kJ/mol (p < 0.05). YA gels exhibited excellent thickening and heat tolerance and behaved as weak gels over an AP concentration range of 0.1-0.4% but as true gels at higher concentrations (e.g. 0.8%). The viscosity/elasticity of the combinations weakened with NaCl addition or extreme pH values. A complex 3-dimensional network structure of the YA system was confirmed by scanning electron microscopy. These results indicated that AP has great potential for functional applications in the starchy food industry.

Antidiabetic activity of Ganoderma lucidum polysaccharides F31 down-regulated hepatic glucose regulatory enzymes in diabetic mice

ETHNOPHARMACOLOGICAL RELEVANCE

Ganoderma lucidum (Lin Zhi) has been used to treat diabetes in Chinese folk for centuries. Our laboratory previously demonstrated that Ganoderma lucidum polysaccharides (GLPs) had hypoglycemic effects in diabetic mice. Our aim was to identify the main bioactives in GLPs and corresponding mechanism of action.

MATERIALS AND METHODS

Four polysaccharide-enriched fraction were isolated from GLPs and the antidiabetic activities were evaluated by type 2 diabetic mice. Fasting serum glucose (FSG), fasting serum insulin (FSI) and epididymal fat/BW ratio were measured at the end of the experiment. In liver, the mRNA levels of hepatic glucose regulatory enzymes were determined by quantitative polymerase chain reaction (qPCR) and the protein levels of phospho-AMP-activated protein kinase (p-AMPK)/AMPK were determined by western blotting test. In epididymal fat tissue, the mRNA and protein levels GLUT4, resistin, fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC1) were determined by qPCR and immuno-histochemistry. The structure of polysaccharide F31 was obtained from GPC, FTIR NMR and GC-MS spectroscopy, RESULTS: F31 significantly decreased FSG (P<0.05), FSI and epididymal fat/BW ratio (P<0.01). In liver, F31 decreased the mRNA levels of hepatic glucose regulatory enzymes, and up-regulated the ratio of phospho-AMP-activated protein kinase (p-AMPK)/AMPK. In epididymal fat tissue, F31 increased the mRNA levels of GLUT4 but decreased fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC1) and resistin. Immuno-histochemistry results revealed F31 increased the protein levels of GLUT4 and decreased resistin.

CONCLUSION

Data suggested that the main bioactives in GLPs was F31, which was determined to be a β-heteropolysaccharide with the weight-average molecular weight of 15.9kDa. The possible action mechanism of F31 may be associated with down-regulation of the hepatic glucose regulated enzyme mRNA levels via AMPK activation, improvement of insulin resistance and decrease of epididymal fat/BW ratio. These results strongly suggest that F31 has antidiabetic potential.

Chinese medicines in the treatment of experimental diabetic nephropathy

Diabetic nephropathy (DN) is a severe micro vascular complication accompanying diabetes mellitus that affects millions of people worldwide. End-stage renal disease occurs in nearly half of all DN patients, resulting in large medical costs and lost productivity. The course of DN progression is complicated, and effective and safe therapeutic strategies are desired. While the complex nature of DN renders medicines with a single therapeutic target less efficacious, Chinese medicine, with its holistic view targeting the whole system of the patient, has exhibited efficacy for DN management. This review aims to describe the experimental evidence for Chinese medicines in DN management, with an emphasis on the underlying mechanisms, and to discuss the combined use of herbs and drugs in DN treatment.

Auricularia polytricha aqueous extract supplementation decreases hepatic lipid accumulation and improves antioxidative status in animal model of nonalcoholic fatty liver

Background: Amelioration effect of Auricularia polytricha water extract (AP) on hepatic injury in an animal model of NAFLD was investigated. Methods: Forty six-week-old Wistar rats were housed and thirty-two fed ten percent lard high-fat diet to induce NAFLD. After eight weeks of induction, animals were divided into five groups of eight rats each: normal control, high-fat diet, RN (reversion to a normal diet), 1× AP (normal diet plus 0.75% AP, w/w), and 2×AP (normal diet plus 1.5% AP). Animals were sacrificed four weeks later. Results: Rats receiving either 0.75% or 1.5% AP exhibited effective interruption of NAFLD progression, as evidenced by decreased lipid accumulation and elevated antioxidative status. Histological examination proved AP anti-inflammatory function and lower level of related markers for tumor necrosis factor-α and interleukin-6. Besides abundant polysaccharides against lipid accumulation, AP had a specific high level of phenolic compounds and tannins thus may be a potent anti-inflammatory and antioxidative agent. Conclusion: Findings suggest that under normal diet recovery, AP supplement may represent novel, protective material against NAFLD by attenuating inflammatory response, oxidative stress and lipid deposition.

Anti-inflammatory Activity of Dichloromethane Extract of Auricularia auricula-judae in RAW264.7 Cells

The present study investigated the anti-inflammatory effects of dichloromethane extract of Auricularia auricula-judae. Dichloromethane extract of Auricularia auricula-judae inhibited Lipopolysaccharide (LPS) -induced nitric oxide (NO) production significantly in a dose-dependent manner in the concentration ≥10 μg/ml (p < 0.05) . Furthermore, RT-PCR results of this study indicated that the extract markedly reduced the expressions of inflammatory cytokines (IL-6, TNF-α and IL-1β) mRNA in LPS-treated murine RAW 264.7 macrophages, which could possibly ameliorate the inflammation. Nevertheless, dichloromethane extract of Auricularia auricula-judae did not show complete inhibition of IL-6 mRNA expression. The inhibition of IL-1β cytokine at protein level was also observed in a dose dependent manner. In conclusion,the current study revealed the previously unknown effect of dichloromethane ethyl extract of Auricularia auricula-judae inhibitions of the production of NO, IL-6, TNF-α and IL-1β in LPS-stimulated macrophages.

Lipid peroxidation and its toxicological implications

Lipid peroxidation is a free radical oxidation of polyunsaturated fatty acids such as linoleic acid or arachidonic acid. This process has been related with various pathologies and disease status mainly because of the oxidation products formed during the process. The oxidation products include reactive aldehydes such as malondialdehyde and 4-hydroxynonenal. These reactive aldehydes can form adducts with DNAs and proteins, leading to the alterations in their functions to cause various diseases. This review will provide a short summary on the implication of lipid peroxidation on cancer, atherosclerosis, and neurodegeneration as well as chemical and biochemical mechanisms by which these adducts affect the pathological conditions. In addition, select examples will be presented where antioxidants were used to counteract oxidative damage caused by lipid peroxidation. At the end, isoprostanes are discussed as a gold standard for the assessment of oxidative damages.

Pulsed electric field extraction enhanced anti-coagulant effect of fungal polysaccharide from Jew's ear (Auricularia auricula)

INTRODUCTION

As a Chinese herbal medicine, Jew's ear has been known for its anti-coagulant effects. Hence it is worthwhile developing an effective technique to extract active components.

OBJECTIVE

To find the optimal extraction condition and to identify the best strain to yield fungal polysaccharide with anti-coagulant activity.

METHODOLOGY

Three strains of Jew's ear from Jilin Province, named as 988, DY 18 and FS 02, and three extraction techniques, namely, high intensity pulsed electric fields (HIPEF), microwave-assisted extraction method (MAEM) and ultrasonic-assisted extraction method (UAEM), were applied to optimise the extraction conditions. The crude extracts and polysaccharides were further determined for anti-coagulant activities.

RESULTS

All extracts prolonged blood clotting time as compared to reagent control. The HIPEF exhibited the most remarkable effect among the three extraction techniques. The anti-coagulant activities of extracts were enhanced with increasing electric field strength when the field strength reached 24 kV/cm.

CONCLUSION

Current results suggest that the HIPEF technique will be an effective method in the manufacture of bioactive natural polysaccharide.

Hypoglycemic effects of Ganoderma lucidum polysaccharides in type 2 diabetic mice

Our aims were to investigate the hypoglycemic effects and mechanisms of action of Ganoderma lucidum polysaccharides (GLPs) administered for 7 days in type 2 diabetic mice. The mice were randomly divided into four groups (8 mice/group): normal control group, diabetic control group, low-dose GLP-treated diabetic group (50 mg/kg/d), and high-dose GLP-treated diabetic group (100 mg/kg/d). Diabetes was induced by streptozotocin injection and high-fat dietary feeding. At the end of the study, fasting serum glucose, insulin, body weight (BW) and epididymal white adipose tissue weight were measured. The hepatic mRNA levels of glycogen phosphorylase (GP), fructose-1,6-bisphosphatase (FBPase), phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) genes were determined by real-time polymerase chain reaction. Both doses of GLPs significantly decreased fasting serum glucose, insulin and epididymal fat/BW ratio compared with the diabetic control group (p < 0.05). The hepatic mRNA levels of GP, FBPase, PEPCK and G6Pase were significantly lower in both GLP-treated groups compared with the diabetic control group. Taken together, GLPs significantly decrease fasting serum glucose levels in type 2 diabetic mice in a dose-dependent manner. The decreases in fasting serum glucose levels may be associated with decreased mRNA expression levels of several key enzymes involved in gluconeogenesis and/or glycogenolysis.

Hypolipidemic effect of Pleurotus eryngii extract in fat-loaded mice

Pleurotus eryngii water extract (PEE), which showed the most significant inhibitory activity against pancreatic lipase in vitro among eight edible mushrooms, was investigated to determine the mechanism of its anti-lipase activity in vitro and its hypolipidemic effect in fat-loaded mice. The inhibitory effects of mushroom extracts on pancreatic lipase activity were examined using 4-methylumbelliferyl oleate (4-MUO) or trioleoylglycerol emulsified with lecithin, gum arabic or Triton X-100 as a substrate. For in vivo experiments, blood samples were taken after oral administration of corn oil and [(3)H]trioleoylglycerol with or without PEE to food-deprived mice. PEE inhibited hydrolysis of 4-MUO and trioleoylglycerol emulsified with lecithin or Triton X-100, but not that of trioleoylglycerol emulsified with gum arabic. PEE suppressed the elevations of plasma and chylomicron triacylglycerol levels after oral administration of corn oil, but had no effect on lipoprotein lipase activity. [(3)H]Trioleoylglycerol absorption was also decreased by administration of PEE. The results of in vitro studies suggest that PEE may prevent interactions between lipid emulsions and pancreatic lipase. The hypolipidemic effect of PEE in fat-loaded mice may be due to low absorption of fat caused by the inhibition of pancreatic lipase.

Anti-hyperglycemic activity of the leaves of Tetracera scandens Linn. Merr. (Dilleniaceae) in alloxan induced diabetic rats

AIM OF THE STUDY

The present study was aimed to investigate the anti-diabetic potential of the leaves of Tetracera scandens Linn. Merr. (Dilleniaceae) in vivo with regard to prove its efficacy by local herbalists in the treatment of diabetes frailties.

MATERIALS AND METHODS

Crude aqueous (AQ) and methanol (MEOH) extracts of the leaves of T. scandens L. were administered to both normal and alloxan induced diabetic male albino rats (Wistar strain). The blood glucose levels were measured at 0, 2, 4, 6 and 8h after oral administration of AQ and MEOH extracts.

RESULTS

Significant reduction in glucose was observed in fasting blood glucose levels in the treated diabetic rats without causing any hypoglycemic effect compared to normal rats. Both polar extracts of the leaves of T. scandens L. exhibited significant anti-hyperglycemic activity at different doses and intervals. The highest anti-hyperglycemic effect (62.5%) was observed by the AQ extract at 0.25 g/kg body weight (b.w.) and MEOH extract (36.5%) at 0.5 g/kg b.w. after 8h. The significant anti-hyperglycemic activity was found to be comparable with a known oral synthetic hypoglycemic drug, glibenclamide 0.25mg/kg b.w.

CONCLUSION

This study provides scientific evidence that the leaves of T. scandens L. have anti-diabetic efficacy and justifies its utility by local herbalists. However, more experiments at the clinical levels are required to confirm the utility of this plant by traditional practitioners in the management of diabetes mellitus.

Hypoglycemic polysaccharides from the tuberous root of Liriope spicata

Previous studies showed that the water extract and crude polysaccharides from the tuberous root of Liriope spicata var. prolifera showed high hypoglycemic and hypolipidemic activities. In the present study, two new water-soluble polysaccharides, named LSP1 and LSP2, were isolated from the active crude polysaccharides by DEAE-cellulose 52 and AB-8 macroporous resin chromatography and tested for their hypoglycemic effects. On the basis of the chemical and physical data obtained, LSP1 and LSP2 are two fructans with the molecular weights 3.20 and 4.29 kDa, respectively, which both have a backbone structure of beta-(1-->2)-fructosyl residues that branches at O-6 with fructosyl residues and terminates with a glucosyl residue and a fructosyl residue. Preliminary activity tests revealed that both LSP1 and LSP2 caused a significant decrease of the fasting blood glucose (FBG) and a significant improvement on glucose tolerance in type 2 diabetic mice. These results suggest that LSP1 and LSP2 show high potential to be explored as natural oral hypoglycemic agents.

Immunological, Hematological, and Glycemia Effects of Dietary Supplementation withAgaricus sylvaticuson Patients’ Colorectal Cancer

Objective: The aim of this study was to evaluate the effects of dietary supplementation with Agaricus sylvaticus fungus on hematological, immunological, and glycemia levels of postsurgical patients with colorectal cancer. Methods: A randomized, placebo-controlled, clinical trial was conducted at the General Hospital of Brazil for 6 months. Fifty-six patients with colorectal cancer (stages I, II, and III) were divided into 2 groups: A. sylvaticus (30 mg/kg/day) and placebo. Complete hemogram, serum iron, and fasting glycemia evaluations were carried out throughout the treatment course. Subjects were divided according to body mass index (BMI), sex, and stage of colorectal cancer. Data were analyzed using SPSS 14.0 programs, Student’s t test, and F statistical test, with P ≤ 0.05 considered significant. Results: After 6 months of supplementation, the group that received A. sylvaticus showed significant increases in hemoglobin ( P = 0.0001), hematocrit ( P = 0.0001), erythrocytes ( P = 0.01), mean cell volume ( P = 0.01), mean cell hemoglobin ( P = 0.0001), mean cell hemoglobin concentration ( P = 0.0001), and neutrophil levels ( P = 0.0001). The platelet count was significantly reduced ( P = 0.03), but remained within normal levels. No significant alterations were observed in the placebo group. The study group was composed of 32 women (57.1%) and 24 men (42.9%). Mean BMI was 24.65 kg/m2. Glycemia levels in the placebo group (average age 59.14 ± 12.95 years) were: initial, 94.36 ± 15.34 mg/dl; 3 months, 98.12 ± 15.54 mg/dl ( P = 0.03); and 6 months, 98.52 ± 9.03 mg/dl ( P = 0.01). Glycemia levels in the supplemented group (average age 56.34 ± 15.53 years) were: initial, 95.92 ± 11.64 mg/dl, 3 months, 94.88 ± 12.24 mg/dl ( P = 0.65); and 6 months, 92.86 ± 6.82 mg/dl ( P = 0.01). Conclusions: The results of this study suggest that supplementation with A. sylvaticus produces benefits in hematological and immunological parameters and can reduce glycemia levels in patients with colorectal cancer.

Hypoglycemic Effects of Exo-biopolymers Produced by Five Different Medicinal Mushrooms in STZ-induced Diabetic Rats

Hypoglycemic effects of exo-biopolymers (EBP) produced by submerged mycelial cultures of Coriolus versicolor, Cordyceps sinensis, Paecilomyces japonica, Armillariella mellea, and Fomes fomentarius were investigated in streptozotocin (STZ)-induced diabetic rats. The rats from each experimental group were orally administered with EBPs (100 mg/kg BW) daily for 2 weeks. Though the hypoglycemic effect was achieved in all the cases, however, C. versicolor EBP proved as the most potent one. The administration of the C. versicolor EBP substantially reduced (29.9%) the plasma glucose level as compared to the saline administered group (control). It also reduced the plasma total cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST) and, alanine aminotransferase (ALT) levels by 9.22, 23.83, 16.93, and 27.31%, respectively. The sugar and amino acid compositions of this EBP were also analyzed in detail.

Hypoglycemic effects ofGanoderma applanatumandCollybia confluensexo-polymers in streptozotocin-induced diabetic rats

The hypoglycemic effects of Ganoderma applanatum exo-polymer (GAE) and Collybia confluens exo-polymer (CCE) produced by submerged mycelial cultures in streptozotocin (STZ)-induced diabetic rats were investigated. Hypoglycemic effects were achieved in both the GAE- and CCE-treated groups by administration at a level of 100 mg/kg body weight (BW) daily for 3 weeks. The administration of GAE and CCE substantially reduced the plasma glucose levels by as much as 22.0% and 25.9%, respectively, when compared with the control group. The GAE and CCE also lowered the plasma total cholesterol and triglyceride levels by 20.3% and 22.5%, and by 22.7% and 25.5%, respectively. Furthermore, the activity of alanine transaminase (ALT) and aspartate transaminase (AST) was decreased by 23.2% and 20.7% in the GAE-treated group, and it was also reduced by 28.7% and 23.6% in the CCE-treated group. The results strongly demonstrate the potential of GAE and CCE in combating diabetes in experimental animals.

Hypolipidemic Effects of Biopolymers Extracted from Culture Broth, Mycelia, and Fruiting Bodies of Auricularia auricula-judae in Dietary-induced Hyperlipidemic Rats

Hypolipidemic effect of biopolymers extracted from culture broth (CP), mycelia (MP), and fruiting bodies (FP) of Auricularia auricula-judae was investigated in dietary-induced hyperlipidemic rats. The experimental animals were administrated (100 mg/kg body weight) with different biopolymers, daily for 4 weeks. Hypolipidemic effects were achieved in all the experimental groups, however, FP was proved to be the most potent one. The administration of the FP reduced the plasma triglyceride, total cholesterol, low-density lipoprotein cholesterol, and atherogenic index by 24.3, 28.5, 36.4, and 40.9%, respectively, while increased the high-density lipoprotein cholesterol level (9.0%), when compared to the saline (control) administered group.

Effect of fungal polysaccharides on the modulation of plasma proteins in streptozotocin-induced diabetic rats

To search out novel biomarkers for monitoring diabetes prognosis, we examined the effect of hypoglycemic fungal exopolysaccharides (EPS) on the differential levels of plasma proteins in streptozotocin-induced diabetic rats. The orally administrated EPS exhibited an excellent hypoglycemic effect, lowering the average plasma glucose level, and increasing insulin secretion in diabetic rats. The 2-DE analysis of rat plasma demonstrated that about 500 visualized spots were differentially regulated, of which 20 spots were identified as principal diabetes-associated proteins. The distinct effect of diabetes induction on the pattern of rat plasma proteins includes the down-regulation of albumin, apolipoprotein E (Apo E), alpha1-inhibitor-3, fetuin beta, Gc-globulin, hemopexin, vitronectin, and transthyretin (TTR) monomer, and the up-regulation of Apo A-I, Apo A-IV, ceruloplasmin, alpha1-antitrypsin, serine protease inhibitor III, and transferrin. Those protein levels were interestingly restored to those of healthy rats by EPS treatment, although the order of magnitude of the changes differed widely. Two proteins of interest showed distinct differential expression with opposite trends: TTR tetramer was significantly down-regulated and immunoglobulin (Ig) kappa light chain was significantly up-regulated upon diabetes induction, both of which were also normalized to those of healthy groups after EPS treatment.

Antihyperglycemic effect of polysaccharide from fermented broth of Pleurotus citrinopileatus

Pleurotus citrinopileatus is an edible mushroom, which has recently become very popular, with a consequent increase in industrial production. Water-soluble polysaccharides (WSPS), extracted from edible mushrooms, have been found to have antitumor and immunoenhancing effects. In this study, we investigate the effects of WSPS extracted from submerged fermented medium of P. citrinopileatus on hyperglycemia and damaged pancreatic cells in rats with streptozotocin (STZ)-induced diabetes. The diabetic rats fed with water-soluble polysaccharide of P. citrinopileatus (SPPC) lost less body weight than those fed SPPC-free regular diet. Serum total cholesterol and triglyceride levels in the diabetic rats fed with SPPC at a dose of 0.4 g/kg bw daily was lower than in the groups fed with SPPC at doses of 0.04 and 0.12 g/kg bw. The fasting blood glucose levels of diabetic rats fed with SPPC were 44% lower than the negative controls. The degree of damage to the islets of Langerhans of the rats fed with the highest dosage of SPPC was significantly lower than those fed with SPPC at doses of 0.04 and 0.12 g/kg bw. The results showed that STZ-induced diabetic rats fed with SPPC might help alleviate the elevation of the level of that in fasting blood glucose.

Antidiabetic and hypolipidemic effects ofCollybia confluens mycelia produced by submerged culture in streptozotocin-diabetic rats

This investigation was undertaken to study the effects of oral administration (3 weeks) of Collybia confluens mycelial powder (CCMP) produced by a submerged culture on plasma glucose and other biochemical parameters in streptozotocin (STZ)-induced diabetic rats. Antidiabetic and hypolipidemic effects were proportionally increased with the increasing concentration of the CCMP for oral administration. The CCMP, at the dose of 400 mg/kg BW, substantially reduced the plasma glucose level by as much as 33.1% as compared to the STZ-induced diabetic rats group. It also lowered the plasma total cholesterol, triglyceride, and low density lipoprotein (LDL) cholesterol by 22.9%, 19.9%, and 37.3%, respectively. The levels of total cholesterol and triglyceride in liver were reduced to the extent of by 13.5% and 18.8%, and the activity of alanine transaminase (ALT) and aspartate transaminase (AST) was decreased by 48.8% and 37.2%, respectively, under the influence of CCMP. The general components of CCMP were found to contain 26.18% carbohydrate, 3.67% crude ash, 4.02% crude fat, 22.55% crude protein, and 43.58% dietary fiber. The amino acid composition of the CCMP was also analyzed in detail.