Botanical origin of Mei-gui Hua in Chinese markets.

The petals or buds of Rosa species have been used as an important Chinese crude drug called "Mei-gui Hua" and also an ingredient for herbal tea in China. The 15 flavonol glycosides in 34 commercially available "Mei-gui Hua" were quantitatively determined by UPLC, and the data were compared with those of known Rosa sp. belong to Cinnamomeae, Gallicanae, Caninae and Synstylae by principal component analysis for the estimation of original plants of these "Mei-gui Hua". Seven samples were classified into two groups (Types A and B) composed of species in Gallicae and Synstilae and 11 samples into a group (Type D) composed of species in Cinnamomeae. Six samples were plotted among Types B, C and D. However, nine samples were shown to form a new group (Type F), and the original plants of these samples were assumed to be more complex hybrids of Rosa species including other sections than Cinnamomeae, Gallicanae, Caninae and Synstylae. This method must be useful and convenient to estimate the origin of crude drug "Mei-gui Hua" commercially available in markets. The results of this study also demonstrated that "Mei-gui Hua" commercially available in Chinese market must be prepared from hybrids of various species of Rosa, and it is not reasonable to assign only R. rugosa as scientific name of the origin plants.

Anagliptin ameliorates albuminuria and urinary liver-type fatty acid-binding protein excretion in patients with type 2 diabetes with nephropathy in a glucose-lowering-independent manner.

OBJECTIVE: The objective of this study is to elucidate the effect of anagliptin on glucose/lipid metabolism and renoprotection in patients with type 2 diabetic nephropathy. METHODS: Twenty-five patients with type 2 diabetic nephropathy received anagliptin 200 mg/day for 24 weeks, and 20 patients who were switched to anagliptin from other dipeptidyl peptidase-4 (DPP-4) inhibitors were analyzed regarding primary and secondary endpoints. The primary endpoint was change in hemoglobin A1c (HbA1c) during treatment with anagliptin. Additionally, we evaluated changes in lipid data (low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and triglyceride), blood pressure (BP), urinary albumin to creatinine ratio (UACR), liver-type fatty acid-binding protein to creatinine ratio (ULFABP) and renal function (estimated glomerular filtration rate and serum cystatin C) as secondary endpoints. RESULTS: After switching to anagliptin from other DPP-4 inhibitors, the levels of HbA1c in the 20 participants showed no significant change, 7.5%±1.2% at 24 weeks compared with 7.3%±0.9% at baseline. The levels of the log10-transformed UACR were significantly reduced from 1.95±0.51 mg/g creatinine (Cr) at baseline to 1.76±0.53 mg/g Cr at 24 weeks after anagliptin treatment (p<0.01). The percentage change in the UACR (Δ%UACR) from baseline to 24 weeks was also significantly lower by -10.6% (p<0.001). Lipid data, systolic BP and renal function were not changed during anagliptin treatment. Additionally, ULFABP in eight participants, who had ≥5 µg/g Cr at baseline, was significantly decreased from baseline (8.5±2.8 µg/g Cr) to 24 weeks (3.1±1.7 µg/g Cr, p<0.01) after anagliptin treatment, and the percentage change in the ULFABP during anagliptin treatment was -58.1% (p<0.001). CONCLUSIONS: Anagliptin induced no significant change in HbA1c, lipid data, systolic BP and renal function. However, anagliptin reduced the UACR and ULFABP, although without a corresponding change in HbA1c, indicating direct action of anagliptin on renoprotection in patients with type 2 diabetic nephropathy.

Antimicrobial constituents of peel and seeds of camu-camu (Myrciaria dubia).

Various antimicrobial constituents of camu-camu fruit were isolated. Acylphloroglucinol (compound 1) and rhodomyrtone (compound 2) were isolated from the peel of camu-camu (Myrciaria dubia) fruit, while two other acylphloroglucinols (compounds 3 and 4) were obtained from camu-camu seeds. The structures of the isolated compounds were characterized by spectrophotometric methods. Compounds 1 and 4 were confirmed to be new acylphloroglucinols with different substituents at the C7 or C9 position of 2, and were named myrciarone A and B, respectively. Compound 3 was determined to be isomyrtucommulone B. This is the first report of the isolation of 3 from a natural resource. The antimicrobial activities of compounds 1, 3, and 4 were similar to those of 2, and the minimum inhibitory concentrations were either similar to or lower than that of kanamycin. These results suggest that the peel and seeds of camu-camu fruit could be utilized for therapeutic applications.

Volatile Components of the Essential Oil of Artemisia montana and Their Sedative Effects.

The sedative effects of volatile components in the essential oil of Artemisia montana ("Yomogi") were investigated and measured using gas chromatography-mass spectrometry (GC-MS). Major components identified included 1,8-cineol, camphor, borneol, α-piperitone, and caryophyllene oxide. Among them, 1,8-cineol exhibited the highest flavor dilution (FD) value in an aroma extract dilution analysis (AEDA), followed by borneol, o-cymene, ß-thujone, and bornyl acetate. The sedative effects of yomogi oil aroma were evaluated by sensory testing, analysis of salivary α-amylase activity, and measurement of relative fluctuation of oxygenated hemoglobin concentration in the brain using near-infrared spectroscopy (NIRS). All results indicated the stress-reducing effects of the essential oil following nasal exposure, and according to the NIRS analysis, 1,8-cineol is likely responsible for the sedative effects of yomogi oil.

Restoration of the Hypothalamic-pituitary-adrenal Response to Hypoglycemia in Type 2 Diabetes by Avoiding Chronic Hypoglycemia.

An impaired ability to sense and respond to drug-induced hypoglycemia is a common and serious complication in diabetic patients. The hypothalamic-pituitary-adrenal (HPA) axis activity plays a critical role in the counterregulatory response to hypoglycemia. We herein report a case that experienced restoration of a blunted HPA axis by avoiding hypoglycemia with the use of the DPP-4 inhibitor sitagliptin.

Effect of sodium-alginate and laminaran on Salmonella Typhimurium infection in human enterocyte-like HT-29-Luc cells and BALB/c mice.

Brown algal polysaccharides such as alginate, polymers of uronic acids, and laminaran, beta-1,3 and 1,6-glucan, can be fermented by human intestinal microbiota. To evaluate the effects of these polysaccharides on infections caused by food poisoning pathogens, we investigated the adhesion and invasion of pathogens (Salmonella Typhimurium, Listeria monocytogenes and Vibrio parahaemolyticus) in human enterocyte-like HT-29-Luc cells and in infections caused in BALB/c mice. Both sodium Na-alginate and laminaran (0.1% each) inhibited the adhesion of the pathogens to HT-29-Luc cells by approximately 70-90%. The invasion of S. Typhimurium was also inhibited by approximately 70 and 80% by Na-alginate and laminaran, respectively. We observed that incubation with Na-alginate for 18 h increased the transepithelial electrical resistance of HT-29-Luc monolayer cells. Four days after inoculation with 7 log CFU/mouse of S. Typhimurium, the faecal pathogen count in mice that were not fed polysaccharides (control mice) was about 6.5 log CFU/g while the count in mice that were fed Na-alginate had decreased to 5.0 log CFU/g. The liver pathogen count, which was 4.1 log CFU/g in the control mice, was also decreased in mice that were fed Na-alginate. In contrast, the mice that were fed laminaran exhibited a more severe infection than that exhibited by control mice.

Diversity in aconitine alkaloid profile of Aconitum plants in Hokkaido contrasts with their genetic similarity.

Aconite tuber is a representative crude drug for warming the body internally in Japanese Kampo medicine and Chinese traditional medicine. The crude drug is used in major prescriptions for the aged. Varieties of Aconitum plants are distributed throughout the Japanese Islands, especially Hokkaido. With the aim of identifying the medicinal potential of Aconitum plants from Hokkaido, 107 specimens were collected from 36 sites in the summer of 2011 and 2012. Their nuclear DNA region, internal transcribed spacer (ITS), and aconitine alkaloid contents were analyzed. Phylogenic analysis of ITS by maximum parsimony analysis showed that the majority of the specimens were grouped into one cluster (cluster I), separated from the other cluster (cluster II) consisting of alpine specimens. The aconitine alkaloid content of the tuberous roots of 76 specimens showed 2 aspects-specimens from the same collection site showed similar aconitine alkaloid profiles, and cluster I specimens from different habitats showed various alkaloid profiles. Environmental pressure of each habitat is presumed to have caused the morphology and aconitine alkaloid profile of these genetically similar specimens to diversify.

Flavonol glycosides in the petal of Rosa species as chemotaxonomic markers.

Thirteen flavonol glycosides were isolated from the petals of Rosa species belonging to the section Gallicanae, and their structures were identified from their spectroscopic data. These flavonol glycosides, along with two flavonol glycosides isolated from Rosa rugosa, in the petals of 31 Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae were quantitatively analyzed by UPLC. The results indicated that the species belonging to these sections could be classified into four types (Type A, B, C and D) based on the pattern of flavonol glycoside contents, whereas the R. rugosa flavonol glycosides were detected only in section Cinnamomeae. A principal components analysis (PCA) calculated from the 15 flavonol glycosides contained in these samples supported the presence of four types. The distribution of the species in Type D (a group of Cinnamomeae) was shown to reflect close interrelationships, but species in Type B (one group of Gallicanae) could be subdivided into two groups, one of which contained species in section Synstylae. Moreover, the flavonol glycosides were grouped by sugar moieties: a disaccharide composed of two hexoses (S1), a hexose (S2), including a hexose with galloyl group, a pentose (S3), and a disaccharide composed of a hexose and a pentose (S4). The ratios of the amounts of S1-S4 to total flavonol glycoside content indicated that differences among the four sections were more distinctive than the amounts of the 15 flavonol glycosides. The 31 samples were divided into Type B, composed of one type of Gallicanae and Synstylae, Type A+C, composed of another type of Gallicanae and Caninae, and Type D, composed of Cinnamomeae. The R. rugosa flavonol glycosides were shown to be important chemotaxonomic markers for the classification of species in Cinnamomeae, and this method of using flavonol glycosides as chemotaxonomic markers could be useful for the identification of Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae.

Volatile components of essential oil from cultivated Myrica gale var. tomentosa and its antioxidant and antimicrobial activities.

Aromatic components in the essential oil prepared from the leaves of cultivated Myrica gale var. tomentosa were compared with those from oil derived wild plants by using gas chromatography-mass spectroscopy (GC/MS). We found that essential oils from both the wild and cultivated plants contained similar aromatic components such as ß-elemenone, selina 3,7(11)-diene, myrcene, limonene, cymene, 1,8-cineole, and ß-pinene, but the content ratio of the oil was significantly different, which might yield differences in the aromatic properties. The aroma impact components of the essential oils were also determined using GC/MS-Olfactometry (GC/MS-O) and aroma extract dilution analysis. Eight aromatic compounds, including linalool, limonene, and 1,8-cineole, were shown to contribute to the aromatic properties of cultivated M. gale var. tomentosa. The strongest aromatic note was defined as linalool, followed by limonene, 1,8-cineole, and ß-elemenone. The essential oil, ethanol (EtOH), 1,3-butylene glycol (BG), and 1,3-propanediol (PD) extracts prepared from the leaves of cultivated M. gale var. tomentosa also showed antioxidant and antimicrobial activities, that is, they demonstrated scavenger activity against hydroxyl and superoxide radicals in the aqueous phase, and showed inhibitory effects on lipid peroxidation. The essential oil extracts also exhibited antimicrobial activity against gram-positive bacteria, with the lowest minimum inhibitory concentration value against Bacillus subtilis. In conclusion, the essential oil and solvent extracts from cultivated M. gala var. tomentosa have a potential for utilization as food and cosmetic ingredients.

Intraportal GLP-1 stimulates insulin secretion predominantly through the hepatoportal-pancreatic vagal reflex pathways.

We previously reported that glucagon-like peptide-1 (GLP-1) appearance in the portal vein facilitates hepatic vagal afferent activity, and this further augments reflexively the pancreatic vagal efferents in anesthetized rats, suggesting a neuroincretin effect of GLP-1. To determine whether the GLP-1-induced vagal pathways lead to a neuronal-mediated component (NMC) of insulin secretion, we infused GLP-1 at a physiological or pharmacological dose (1 or 3 pmol·kg(-1)·min(-1), respectively) into the portal vein in conscious rats with selective hepatic vagotomy (Vagox) or sham operation (Sham). The experiments consisted of two sequential 10-min intraportal infusions (P1 and P2): glucose at a physiological rate (56 µmol·kg(-1)·min(-1)) in P1 and the glucose plus GLP-1 or vehicle in P2. Under arterial isoglycemia across the groups, the physiological GLP-1 infusion in Sham augmented promptly and markedly arterial insulin levels, approximately twofold the levels in glucose alone infusion (P < 0.005), and insulin levels in Vagox diminished apparently (P < 0.05). Almost 60% of the GLP-1-induced insulin secretion (AUC) in Sham met the NMC, i.e., difference between insulin secretion in Sham and Vagox, (AUC 976 ± 65 vs. 393 ± 94 pmol·min/l, respectively, P < 0.005). Intraportal pharmacological GLP-1 infusion further augmented insulin secretion in both groups, but the NMC remained in 46% (NS; Sham vs. Vagox). In contrast, "isoglycemic" intravenous GLP-1 infusion (3 pmol·kg(-1)·min(-1)) evoked an equal insulin secretion in both groups. Thus, the present results indicate that GLP-1 appearing in the portal vein evokes a powerful neuronal-mediated insulinotropic effect, suggesting the neuroincretin effect.

Three ileus cases associated with the use of dipeptidyl peptidase-4 inhibitors in diabetic patients.

Dipeptidyl peptidase (DPP)-4 inhibitors are a new class of antidiabetic drugs that increase incretin hormone levels to enhance blood sugar level-dependent insulinotropic effects, suppress glucagon action, and reduce bowel motility. These incretin effects are ideal for blood sugar control. However, the safety profile of DPP-4 inhibitors is not yet established. Herein, we present three cases of ileus, considered to be closely related to the use of DPP-4 inhibitors, in diabetic patients. Each of the three patients exhibited some risk of a deficiency in bowel movement; the onset of ileus was within 40 days after strengthened inhibition of DPP-4. The use of a DPP-4 inhibitor could be safe, although the cases presented herein enable us to inform the scientific community to some of the potential adverse effects of the use of DPP-4 inhibitors in select populations.

Effects of holdfast of Laminaria japonica on listeria invasion on enterocyte-like Caco-2 cells and NO production of macrophage RAW 264.7 cells.

Listeria monocytogenes (Lm) causes food poisoning in humans mainly through consumption of ready-to-eat foods. Immunocompromised persons are at the highest risk for infection. We investigated effects of crude soluble polysaccharides (SPS) and ethanolic extract (EE) fractions of frond (kombu) and holdfast (ganiashi) parts of Laminaria japonica on Lm invasion into human enterocyte-like Caco-2 cells and immune and/or inflammatory reactions of murine macrophage RAW 264.7 cells. Recovery and viscosity were high in kombu SPS. Total phenolic content and antioxidant activities (2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity and Fe-reducing power) were higher in ganiashi EE. EE of ganiashi, rather than kombu, suppressed the Lm invasion into the differentiated Caco-2 cells, though the inhibitory effect of SPS was not significant. Ganiashi SPS increased the nitric oxide (NO) production of intact RAW 264.7 cells. On the other hand, the NO production from Escherichia coli O111 lipopolysaccharide-activated cells was suppressed by kombu SPS and ganiashi EE. These results suggest that L. japonica, particularly ganiashi, might suppress the invasion and infection of Lm and also the inflammation.

[Food intake-suppressing action of incretin and anti-obesity therapy].

Suppressing food intake is the most well-known central nervous action of glucagon-like peptide-1 (GLP-1). Neurons expressing preproglucagon (PPG) in the nucleus tractus solitarius (NTS) are the only source of "central" GLP-1, and they project to the hypothalamus. Recently, properties of these PPG-neurons have been revealed using transgenic mice expressing fluorescent protein under control of the PPG promoter; whereas they are directly responsible to leptin but not to GLP-1, they can be the second-order neurons of vagal afferents. "Peripheral" GLP-1 released from intestinal L-cells may possess central nervous action through the vagal afferent fibers. The question remains whether food intake suppression due to "peripheral" GLP-1 depends on "central" one. The action is being applied to anti-obesity therapy.

Elevated serum levels of interleukin-18 in patients with overt diabetic nephropathy: effects of miglitol.

BACKGROUND: Interleukin-18 (IL-18), a pro-inflammatory cytokine, is a predictor of cardiovascular and renal disease in diabetic patients. Postprandial hyperglycemia is one of the important factors contributing to an increase in the circulating pro-inflammatory cytokine levels. This study investigated the effect of miglitol, an α-glucosidase inhibitor, on postprandial hyperglycemia and IL-18 levels in diabetic patients with nephropathy. METHODS: Fifteen Japanese diabetic patients with persistent proteinuria and preserved renal function were recruited. The patients received 50 mg miglitol thrice daily after the baseline examinations and were followed up for 12 weeks. A meal tolerance test was performed on eight patients at baseline and week 12. The fasting miglitol concentration was measured in seven patients just before the meal tolerance test. RESULTS: There were no changes in the body weight, blood pressure, liver and renal function, and proteinuria from baseline to week 12. However, the levels of glycated hemoglobin and interleukin 18 significantly decreased from baseline to week 12. During the meal tolerance test, plasma glucose was significantly decreased 60 min after treatment with miglitol, whereas the serum concentration of insulin was not changed. Fasting and postprandial levels of IL-18 were significantly decreased from baseline to week 12. Serum miglitol concentrations showed a significantly negative correlation with eGFR (r = -0.82, p = 0.02). However, the serum miglitol concentrations did not changed during the course of this study. CONCLUSION: Miglitol improved postprandial hyperglycemia and reduced serum IL-18 levels in patients with stage 3 diabetic nephropathy. Miglitol may therefore prevent atherosclerotic diseases and diabetic micro-vascular complications through decreasing glucose swings and/or the circulating IL-18 level.

Low-Frequency Electroacupuncture Improves Insulin Sensitivity in Obese Diabetic Mice through Activation of SIRT1/PGC-1α in Skeletal Muscle.

Electroacupuncture (EA) has been observed to reduce insulin resistance in obesity and diabetes. However, the biochemical mechanism underlying this effect remains unclear. This study investigated the effects of low-frequency EA on metabolic action in genetically obese and type 2 diabetic db/db mice. Nine-week-old db/m and db/db mice were randomly divided into four groups, namely, db/m, db/m + EA, db/db, and db/db + EA. db/m + EA and db/db + EA mice received 3-Hz electroacupuncture five times weekly for eight consecutive weeks. In db/db mice, EA tempered the increase in fasting blood glucose, food intake, and body mass and maintained insulin levels. In EA-treated db/db mice, improved insulin sensitivity was established through intraperitoneal insulin tolerance test. EA was likewise observed to decrease free fatty acid levels in db/db mice; it increased protein expression in skeletal muscle Sirtuin 1 (SIRT1) and induced gene expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), nuclear respiratory factor 1 (NRF1), and acyl-CoA oxidase (ACOX). These results indicated that EA offers a beneficial effect on insulin resistance in obese and diabetic db/db mice, at least partly, via stimulation of SIRT1/PGC-1α, thus resulting in improved insulin signal.

Botanical origin of mei-gui hua (petal of a Rosa species).

Mei-gui hua has been used as a crude drug in traditional medicine and as herbal tea in China. The scientific name of Mei-gui is Rosa rugosa thunb. However, the morphological characteristics and botanical ecology of Mei-gui were different from those of R. rugosa. Since the botanical origins of Mei-gui cultivated in China have not yet been clarified, we compared Mei-gui and R. rugosa in terms of their morphological characteristics, phylogenetic analysis, and phytochemical studies. Our research suggested that Mei-gui cultivated around Tarim Basin in Xinjiang Province showed homology to Rosa gallica, while those cultivated in the northeastern parts of China are considered to be hybrids of R. rugosa.

Simultaneous determination of hydrolysable tannins in the petals of Rosa rugosa and allied plants.

The petals of Rosa rugosa and allied plants for medicinal use contain abundant hydrolysable tannins, and they show remarkable biological activities. The activities are dependent on the structures of the hydrolysable tannins, so their contents and compositions are essential for evaluation of medicinal potency. Therefore, we optimized the simultaneous quantitative determination of the hydrolysable tannins using ultra-performance liquid chromatography. A column of ethylene bridged hybrid (BEH) phenyl (C(6) alkyl phenyl group as solid-phase modification) was shown to be most effective for the separation of hydrolysable tannins isolated from R. rugosa and related compounds when the column temperature was kept under 25 degrees C. The efficacy of the BEH phenyl column might be due to the interaction between solid phase and phenolic ester groups of hydrolysable tannins such as galloyl, hexahydroxydiphenoyl and valoneoyl groups. The relation between the retention times on the BEH phenyl column and the column temperature was demonstrated to depend on the structural characteristics of hydrolysable tannins.

Inhibitory effects of Rosa gallica on the digestive enzymes.

The 50% aqueous ethanol extracts of petals of Rosa gallica collected in Xinjiang province, China, exhibited potent inhibitory effects against alpha-amylase and alpha-glucosidase. As the active principles, seven hydrolysable tannins were isolated from this species for the first time and elucidated by NMR and ESI-TOF-MS analysis. Quantitative analysis by ultra-performance liquid chromatography demonstrated that the contents of these hydrolysable tannins were 3-5% of the dry weight of the petals, and the hydrolysable tannins must be related to the medicinal utilization of this species.

Flavobacterium algicola sp. nov., isolated from marine algae.

A rod-shaped Gram-staining-negative, non-motile, aerobic and fucoidan-digesting strain, designated TC2(T), was isolated from marine algae collected from the coast of the Sea of Okhotsk at Abashiri, Hokkaido, Japan. The bacterium formed yellow, translucent, circular and convex colonies. Comparative 16S rRNA gene sequence analysis indicated that the strain belonged to the genus Flavobacterium, with the highest sequence similarities of 97.1 to 97.3 % to the type strains of Flavobacterium frigidarium, Flavobacterium frigoris, Flavobacterium limicola and Flavobacterium psychrolimnae. DNA-DNA relatedness values between strain TC2(T) and the above-mentioned species were lower than 28 %. The genomic DNA G+C content was 33.9 mol%. The major respiratory quinone was menaquinone-6 and the predominant fatty acids were iso-C(15 : 1) G, iso-C(15 : 0), iso-C(15 : 0) 3-OH and summed feature 3 (which comprises iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c). Strain TC2(T) could be differentiated from related species by several phenotypic characteristics. Thus, on the basis of these results, strain TC2(T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium algicola sp. nov. is proposed. The type strain is TC2(T) (=NBRC 102673(T) =CIP 109574(T)).

Acetaldehyde tolerance in Saccharomyces cerevisiae involves the pentose phosphate pathway and oleic acid biosynthesis.

To identify genes responsible for acetaldehyde tolerance, genome-wide screening was performed using a collection of haploid Saccharomyces cerevisiae strains deleted in single genes. The screen identified 49 genes whose deletion conferred acetaldehyde sensitivity, and these were termed the genes required for acetaldehyde tolerance. We focused on six of these genes required for acetaldehyde tolerance, ZWF1, GND1, RPE1, TKL1 and TAL1, which encode enzymes in the pentose phosphate pathway (PPP), and OAR1, which encodes for NADPH-dependent 3-oxoacyl-(acyl-carrier-protein) reductase. These genes were not only responsible for acetaldehyde tolerance but also turned out to be induced by acetaldehyde. Moreover, the content of oleic acid was remarkably increased in yeast cells under acetaldehyde stress, and supplementation of oleic acid into the media partially alleviated acetaldehyde stress-induced growth inhibition of strains disrupted in the genes required for acetaldehyde tolerance and OLE1. Taken together, our data suggest that the supply of NADPH and the process of fatty acid biosynthesis are the key factors in acetaldehyde tolerance in the yeast, and that oleic acid plays an important role in acetaldehyde tolerance.