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The combination of freeze-dried aronia, red ginseng, ultraviolet-irradiated shiitake mushroom and nattokinase (AGM; 3.4:4.1:2.4:0.1) was examined to evaluate its effects on insulin resistance, insulin secretion and the gut microbiome in a non-obese type 2 diabetic animal model. Pancreatectomized (Px) rats were provided high fat diets supplemented with either (1) 0.5 g AGM (AGM-L), (2) 1 g AGM (AGM-H), (3) 1 g dextrin (control), or (4) 1 g dextrin with 120 mg metformin (positive-control) per kg body weight for 12 weeks. AGM (1 g) contained 6.22 mg cyanidin-3-galactose, 2.5 mg ginsenoside Rg3 and 244 mg β-glucan. Px rats had decreased bone mineral density in the lumbar spine and femur and lean body mass in the hip and leg compared to the normal-control and AGM-L and AGM-H prevented the decrease. Visceral fat mass was lower in the control group than the normal-control group and its decrease was smaller with AGM-L and AGM-H. HOMA-IR was lower in descending order of the control, positive-control, AGM-L, AGM-H and normal-control groups. Glucose tolerance deteriorated in the control group and was improved by AGM-L and AGM-H more than in the positive-control group. Glucose tolerance is associated with insulin resistance and insulin secretion. Insulin tolerance indicated insulin resistance was highly impaired in diabetic rats, but it was improved in the ascending order of the positive-control, AGM-L and AGM-H. Insulin secretion capacity, measured by hyperglycemic clamp, was much lower in the control group than the normal-control group and it was improved in the ascending order of the positive-control, AGM-L and AGM-H. Diabetes modulated the composition of the gut microbiome and AGM prevented the modulation of gut microbiome. In conclusion, AGM improved glucose metabolism by potentiating insulin secretion and reducing insulin resistance in insulin deficient type 2 diabetic rats. The improvement of diabetic status alleviated body composition changes and prevented changes of gut microbiome composition.

Background/objectives: The present study investigated the hypothesis that a highly pure linear β-1,3-glucan produced by Agrobacterium sp. R259 enhances human natural killer (NK) cell activity and suppresses pro-inflammatory cytokines., Subjects/methods: In an eight-week, double-blind, randomized, placebo-controlled clinical trial, 83 healthy adults with white blood cell counts of 4,000-8,000 cells/µL were participated and randomly assigned to take two capsules per day containing either 350 mg β-1,3-glucan or placebo. Six participants withdrew their study consent or were excluded due to NK cell activity levels outside the normal range. NK cell activity and serum levels of immunoglobulin G (IgG) and cytokines, such as interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-α were measured., Results: NK cell activity and the serum levels of IL-10 were significantly higher from baseline to week 8 in the β-glucan group compared with the placebo group ( P = 0.048, P = 0.029). Consumption of β-1,3-glucan also significantly increased NK cell activity compared with placebo after adjusting for smoking and stress status ( P = 0.009). In particular, the effect of β-1,3-glucan on NK cell activity was greater in participants with severe stress than in those experiencing mild stress. However, the administration β-1,3-glucan did not significantly modulate the levels of IFN-γ, IL-2, IL-4, IL-6, IL-12, TNF-α and IgG compared with the placebo., Conclusion: The results showed that supplementation with bacterial β-1,3-glucan significantly increased NK cell activity without causing any adverse effects. Additionally, the beneficial effect of β-1,3-glucan on NK cell activity was greater in participants experiencing severe stress., Competing Interests: The authors declare no potential conflicts of interests

The brain is an important modulator of glucose metabolism, and is known to respond Gastrodia elata Blume water extract (GEB). Therefore, we examined whether long-term administration of GEB has hypoglycemic activity, and its action mechanism was explored in partially-pancreatectomized rats that exhibit similar characteristics as Asian type 2 diabetes, non-obese insulin-insufficient diabetes. The rats were provided high-fat diets supplemented with either of (1) 0.5% GEB (GEB-L), (2) 2% GEB (GEB-H), (3) 2% dextrin (control), or (4) 2% dextrin with rosiglitazone (20 mg/kg body weight; positive-control) for eight weeks. GEB dose-dependently improved hypothalamic insulin signaling, enhanced whole-body insulin sensitivity during hyperinsulinemic euglycemic clamp, and reduced hepatic glucose output in a hyperinsulinemic state. GEB dose-dependently increased the area under the curve of the serum insulin levels at the first and second phases during hyperglycemic clamp compared to the control, whereas the positive control had no effect. Insulin sensitivity during the hyperglycemic state also improved, dose-dependently, in response to GEB compared with that of the control, but was less than the positive control. GEB-H increased the mass of β-cells by potentiating proliferation and decreasing apoptosis. In conclusion, GEB could be a therapeutic agent for treating Asian type 2 diabetes.

Objectives: Methyl jasmolate (MeJA)-treated vegetables produce higher concentrations of various bioactive compounds. We investigated whether long-term oral consumption of MeJA-treated and untreated buckwheat sprout powder improves energy, glucose, lipid, and bone metabolism induced by estrogen deficiency in ovariectomized (OVX) rats fed high-fat diets, and explored the mechanisms involved., Methods: OVX rats were divided into four groups and fed high-fat diets supplemented with 3% dextrin (OVX-control), buckwheat sprout powder (BWS), or MeJA-treated buckwheat sprout powder (MJ-BWS) for 12 wk. Sham rats without estrogen deficiency had a control diet as a normal-control., Results: MeJA-treatment increased total polyphenols and flavonoids by about 1.6 fold and isoorientin, orientin, rutin, and vitexin were elevated by about 18% in buckwheat. After 12 wk, OVX rats exhibited increased weight gain, fat mass, skin temperature, hyperglycemia, and decreased bone mineral density (BMD) compared to sham rats. BWS prevented the increase of skin temperature and decrease of femur BMD, but did not improve energy glucose homeostasis as much as MJ-BWS. MJ-BWS prevented increases in body weight and fat mass. Energy expenditure was lowest in OVX-control, followed by BWS, MJ-BWS, and normal-control. Furthermore, MJ-BWS exhibited greater improvements in glucose and insulin tolerance than OVX-control and BWS. Phosphorylation of hepatic Akt and AMPK was potentiated, in ascending order of OVX-control, BWS, MJ-BWS, and normal-control, whereas PEPCK expression was decreased., Conclusions: MJ-BWS prevented and ameliorated the disturbances in energy and glucose metabolism in estrogen-deficient animals better than BWS. Therefore, besides flavonoids in BWS, other components such as phytoalexins produced in MJ-BWS during MeJA-treatment might play a crucial role in the improvement., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background and Objectives: Constipation affects up to 20% of the world's population. The aim of this study was to investigate whether supplementation with Ficus carica paste could be used to treat constipation in Korean subjects with functional constipation., Methods and Study Design: We conducted a randomized, double-blind, placebo-controlled trial. Subjects with functional constipation were orally supplemented with either F. carica paste (n=40) or placebo (n=40) for 8 weeks. We measured the efficacy and safety of F. carica paste. Primary outcomes (colon transit time) and secondary outcomes (questionnaire related to defecation) were compared before and after the 8-week intervention period., Results: F. carica paste supplementation was associated with a significant reduction in colon transit time and a significant improvement in stool type and abdominal discomfort compared with the placebo. Blood parameters and clinical findings for organ toxicity remained within normal ranges., Conclusion: These results suggest that F. carica paste may have beneficial effects in subjects suffering from constipation.

Limonin, one of the major components in dictamni radicis cortex (DRC), has been shown to play various biological roles in cancer, inflammation, and obesity in many different cell types and tissues. Recently, the odorant-induced signal transduction pathway (OST) has gained attention not only because of its function in the perception of smell but also because of its numerous physiological functions in non-neuronal cells. However, little is known about the effects of limonin and DRC on the OST pathway in non-neuronal cells. We investigated odorant-stimulated increases in Ca(2+) and cAMP, major second messengers in the OST pathway, in non-neuronal 3T3-L1 cells pretreated with limonin and ethanol extracts of DRC. Limonin and the extracts significantly decreased eugenol-induced Ca(2+) and cAMP levels and upregulated phosphorylation of CREB and PKA. Our results demonstrated that limonin and DRC extract inhibit the OST pathway in non-neuronal cells by modulating Ca(2+) and cAMP levels and phosphorylation of CREB.

The purpose of this study is to investigate the effects of euphorbiasteroid, a component of Euphorbia lathyris L., on adipogenesis of 3T3-L1 pre-adipocytes and its underlying mechanisms. Euphorbiasteroid decreased differentiation of 3T3-L1 cells via reduction of intracellular triglyceride (TG) accumulation at concentrations of 25 and 50 μM. In addition, euphorbiasteroid altered the key regulator proteins of adipogenesis in the early stage of adipocyte differentiation by increasing the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase. Subsequently, levels of adipogenic proteins, including fatty acid synthase, peroxisome proliferator-activated receptor-γ and CCAAT/enhancer-binding protein α, were decreased by euphorbiasteroid treatment at the late stage of adipocyte differentiation. The anti-adipogenic effect of euphorbiasteroid may be derived from inhibition of early stage of adipocyte differentiation. Taken together, euphorbiasteroid inhibits adipogenesis of 3T3-L1 cells through activation of the AMPK pathway. Therefore, euphorbiasteroid and its source plant, E. lathyris L., could possibly be one of the fascinating anti-obesity agent., (Copyright © 2015 John Wiley & Sons, Ltd.)

Poly-γ-glutamic acid (PGA) is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS). Lastly, PGA promoted activation of 5' adenosine monophosphate-activated protein (AMPK) in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.

Purpose: Brain insulin resistance is related to both diabetes and Alzheimer's disease. We investigated whether both chungkookjangs, soybeans fermented in a traditional method (TFC) and with Bacillus lichenifomis (SFC), can protect against cognitive dysfunction and glucose dysregulation in rats with Alzheimer's disease and type 2 diabetes., Methods: Partial pancreatectomy (Px) and ICV β-amyloid (25-35) infusion into the CA1 region were fed either control diet (AD-CON), 10% cooked soybeans (CSB), 10% TFC, or 10% SFC in a high fat diet for 8 weeks. Px rats infused β-amyloid (35-25) as a normal-control group (Non-AD-CON)., Results: SFC increased isoflavonoid aglycones, DDMP soyasaponin βg, E soyasaponin Be and lysoposphatidylcholines in comparison to CSB. SFC markedly decreased its accumulation in β-amyloid deposition in AD rats and improved hippocampal insulin signaling (pAkt → pGSK → pTau) that exacerbated in AD-CON rats. AD rats markedly impaired cognitive function than Non-AD-CON rats as measured by a water maze and passive avoidance tests while the disturbance was prevented in an ascending order of CON < CSB and TFC < SFC. In comparison to Non-AD rats, AD-CON rats lowered whole body glucose infusion rates and increased hepatic glucose output at hyperinsulinemic state during euglycemic hyperinsulinemic clamp which SFC normalized in AD rats. Interestingly, insulin secretion, especially at the second phase during hyperglycemic clamp, was higher in AD-CON rats, compared to Non-AD rats while CSB, TFC, SFC lowered it in AD-rats. However, SFC restored β-cell mass in AD rats that reduced β-cell mass by increased β-cell apoptosis., Conclusions: β-Amyloid accumulation in the hippocampus exacerbated insulin resistance and decreased β-cell mass and SFC prevented their exacerbation in AD diabetic rats.

We examined the therapeutic effect of an ethanol extract derived from Boehmeria nivea (Linn.) Gaudich in a mouse model of experimental colitis. Treatment with 70% ethanol extract derived from B. nivea (EBN) at a dose of 100, 200, or 500 mg/(kg · d) improved colon shortening, body weight, the disease activity index (DAI), and histopathological score of DSS-induced colitis mice. DSS significantly increased the levels of cyclooxygenase-(COX-) 2 in colon tissue relative to that of the untreated control group. EBN administered at 100, 200, or 500 mg/(kg · d) reduced COX-2 levels in the DSS-treated mice. In addition, EBN decreased the DSS-induced secretion of the inflammatory cytokine interleukin-6 (IL-6) and chemokine monocyte chemotactic protein-1 (MCP-1). Taken together, these data suggest that B. nivea extract is effective in preventing colitis.

In this study, we performed in vitro and in vivo studies to examine whether a 70% ethanol extract of Prunus mume fruits (EMS) exhibits anti-diabetic effects. Treatment with EMS increased glucose uptake in C2C12 myotubes, and also increased PPAR-γ activity or PPAR-γ mRNA expression. To confirm these in vitro results, we next conducted an animal experiment. A high-fat diet significantly increased the body weight, fat accumulation, and glucose levels in mice. Under the same conditions, 5% EMS attenuated the high-fat diet-induced increase in body weight and fat accumulation and improved the impaired fasting glucose level and glucose tolerance. High performance liquid chromatography analysis demonstrated that EMS contained chlorogenic acid, caffeic acid, rutin, luteolin-7-glucoside, naringin, apigenin-7-glucoside, and hesperidin. Taken together, these findings suggest that EMS exerts an anti-diabetic effect both in vitro and in vivo, which is mediated, at least in part, by the activation of PPAR-γ., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

We examined the antidiabetic property of Boehmeria nivea (L.) Gaud. Ethanolic extract of Boehmeria nivea (L.) Gaud. (EBN) increased the uptake of 2-[N-(nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose in C2C12 myotubes. To examine the mechanisms underlying EBN-mediated increase in glucose uptake, we examined the transcriptional activity and expression of peroxisome proliferator-activated receptor gamma (PPAR- γ ), a pivotal target for glucose metabolism in C2C12 myotubes. We found that the EBN increased both the transcriptional activity and mRNA expression levels of PPAR- γ . In addition, we measured phosphorylation and expression levels of other targets of glucose metabolism, such as AMP-activated protein kinase (AMPK) and protein kinase B (Akt/PKB). We found that EBN did not alter the phosphorylation or expression levels of these proteins in a time- or dose-dependent manner, which suggested that EBN stimulates glucose uptake through a PPAR- γ -dependent mechanism. Further, we investigated the antidiabetic property of EBN using mice fed a high-fat diet (HFD). Administration of 0.5% EBN reduced the HFD-induced increase in body weight, total cholesterol level, and fatty liver and improved the impaired fasting glucose level, blood insulin content, and glucose intolerance. These results suggest that EBN had an antidiabetic effect in cell culture and animal systems and may be useful for preventing diabetes.

Antlers have been traditionally used for thousands of years as a natural product with medicinal and pharmaceutical properties. In developing healthy foods, Bacillus-mediated fermentation is widely used to enhance the biological activity of nutrients in foods. Recently, fermentation was shown to enhance the osteogenic activity of antlers. This study aimed to elucidate the antiresorptive activity of Bacillus-fermented antler and its mode of action. We found that Bacillus-fermented antler extract strongly inhibited osteoclast differentiation by downregulating the expression and activity of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1). This extract also inhibited the activation of phospholipase C γ 2 (PLC γ 2), a signaling molecule that could regulate NFATc1 transcriptional activity. This suggested that Bacillus-fermented antler extract could inhibit PLC γ 2-NFATc1 signaling required for bone resorption and cell fusion. Consequently, Bacillus-fermented antler extract might benefit osteoclast-related disorders, including osteoporosis; furthermore, it may improve gastrointestinal activity.

The antidiabetic effect of the Citrus junos Tanaka (also known as yuja or yuzu) was examined. Ethanol extract of yuja peel (YPEE) significantly stimulated 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG) uptake in C2C12 myotubes. However, ethanol extract of yuja pulp (YpEE) and water extract of yuja peel (YPWE) or pulp (YpWE) did not stimulate glucose uptake. In addition, peroxisome proliferator-activated receptor gamma (PPAR-γ) and AMP-activated protein kinase (AMPK) activities were increased by YPEE in a dose-dependent manner. Pretreatment of AMPK inhibitor decreased the glucose uptake stimulated by YPEE in C2C12 myotubes. We confirmed the anti-diabetic effect of YPEE in mice fed a high fat-diet (HFD). Compared with control mice on a normal diet (ND), these mice showed increased body weight, liver fat, insulin resistance, triacylglycerol (TG), and total cholesterol content. Addition of 5% YPEE significantly reduced the weight gain and rise in liver fat content, serum triacylglycerol (TG), total cholesterol, and insulin resistance found in mice fed a high-fat diet (HFD). Moreover, YPEE reduced the secretion of HFD-induced adipocytokines such as leptin and resistin. YPEE also resulted in increased phosphorylation of AMPK in muscle tissues. These results suggest that ethanol extract of yuja peel exerts anti-diabetic effects via AMPK and PPAR-γ in both cell culture and mouse models.

Liver and serum metabolites of obese and lean mice fed on high fat or normal diets were analyzed using ultraperformance liquid chromatography-quadrupole-time-of-flight mass spectrometry, gas chromatography-mass spectrometry, and partial least-squares-discriminant analysis (PLS-DA). Obese and lean groups were clearly discriminated from each other on PLS-DA score plot and major metabolites contributing to the discrimination were assigned as lipid metabolites (fatty acids, phosphatidylcholines (PCs), and lysophosphatidylcholines (lysoPCs)), lipid metabolism intermediates (betaine, carnitine, and acylcarnitines), amino acids, acidic compounds, monosaccharides, and serotonin. A high-fat diet increased lipid metabolites but decreased lipid metabolism intermediates and the NAD/NADH ratio, indicating that abnormal lipid and energy metabolism induced by a high-fat diet resulted in fat accumulation via decreased β-oxidation. In addition, this study revealed that the levels of many metabolites, including serotonin, betaine, pipecolic acid, and uric acid, were positively or negatively related to obesity-associated diseases. On the basis of these metabolites, we proposed a metabolic pathway related to high-fat diet-induced obesity. These metabolites can be used to better understand obesity and related diseases induced by a hyperlipidic diet. Furthermore, the level changes of these metabolites can be used to assess the risk of obesity and the therapeutic effect of obesity management.

Objective: Although soybeans have been shown to alleviate metabolic syndromes, fermented soybeans may have even greater effects. We investigated the antidiabetic effects of meju, a soy food that is fermented up to 2 mo, and the mechanism by which it exerts its effects., Methods: Meju was prepared by a traditional fermentation process: soybeans were fermented outdoors for 20 or 60 d. Methanol (M-60) and water (W-60) extracts from meju that had fermented for 60 d contained mostly isoflavonoid aglycones and small peptides, respectively, as opposed to mostly glycosylated isoflavonoids and proteins in the original soybeans., Results: Daidzein, M-60, and W-60 had better insulin-sensitizing actions by activating peroxisome proliferator-activated receptor-γ in 3T3-L1 adipocytes than did unfermented soybeans. In addition, Min6 insulinoma cells treated with genistein, M-60, and W-60 had greater glucose-stimulated insulin secretion capacity and greater β-cell viability than those treated with unfermented soybeans. This improvement was associated with insulin/insulin-like growth factor-1 signaling that was activated by the tyrosine phosphorylation of insulin receptor substrate-2 and serine phosphorylation of Akt, and this in turn increased pancreatic and duodenal homeobox-1 expression. Furthermore, genistein, daidzein, and M-60 stimulated glucagon-like peptide-1 secretion in enteroendocrine NCI-H716 cells, which generated insulinotropic actions., Conclusion: The compositional changes in isoflavonoids and peptides that occurred during a longer fermentation period, without the use of salt, enhanced the antidiabetic effect of soybeans., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Ethnopharmacological Relevance: Panax ginseng and its major component, ginsenosides, are widely used for the prevention of various disorders in oriental medicine., Aim of the Study: To evaluate the effect of ginsenoside Rc (Rc), one of the active constituents in Panax ginseng, on glucose uptake in C2C12 myotubes., Results: Treatment of the C2C12 myotubes with Rc significantly increased glucose uptake. To determine the mechanism of Rc-induced glucose uptake, either insulin-dependent signaling or insulin-independent signaling pathway activities were measured using western blot analysis. We showed that Rc significantly activated an insulin-independent AMPK signaling pathway. However, Rc had no effect on the components of the insulin-dependent signaling pathway, such as receptor substrates (IRS)-1 and protein kinase B or Akt (PKB/Akt). Moreover, we found that treatment with an AMPK inhibitor abolished both glucose uptake and p38 MAPK phosphorylation. This result implies that AMPK activity is critical for the Rc-induced glucose uptake and that AMPK is situated upstream of p38 MAPK. In addition, we also showed that the activation of AMPK and p38 induced by ginsenoside Rc is mediated by reactive oxygen species (ROS) production, suggesting that upstream regulators of AMPK- and p38 MAPK-mediated glucose uptake., Conclusion: Ginsenoside Rc significantly enhances glucose uptake by inducing ROS generation, which leads to AMPK and p38 MAPK activation. Consequently, ginsenoside Rc can be used as a potent natural anti-diabetic agent., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)