Effect of ethanol extract of dried Chinese yam (Dioscorea batatas) flour containing dioscin on gastrointestinal function in rat model

Effect of Dioscorea Opposite Waste Supplementation on Antioxidant Capacity, Immune Response and Rumen Microbiome in Weaned Lambs

Dioscorea opposite waste (DOW) has been shown to improve the gastrointestinal microbiome, antioxidation capacity, and immune activity, indicating it is a potential feed resource to improve the physiological health and rumen function of weaned lambs. In the present study, the responses of rumen microbiome to DOW supplementation in diet were profiled using metagenome sequencing. In addition, the potential of DOW to regulate plasma parameters in weaned lambs and its possible mechanisms were investigated. Sixty healthy male small tail Han lambs (22.68 ± 2.56 kg) were selected and equally assigned to four dietary treatments: (1) DOW-free diet (CON), (2) addition of 10% DOW diet (DOW1), (3) addition of 15% DOW diet (DOW2), and (4) addition of 20% DOW diet (DOW3). Experimental lambs were fed a corresponding diet for 62 days. Rumen microbiome and plasma parameters were determined at the end of the experiment. The results showed that dietary supplementation with DOW linearly increased the concentration of aspartate aminotransferase, alkaline phosphatase, Immunoglobulin A, Immunoglobulin M, Immunoglobulin G, Glutathione peroxidase, Superoxide dismutase, and total antioxidant capacity in the plasma of weaned lambs, but an opposite trend was observed in Interleukin-1β, Interleukin-6, tumor necrosis factor-α, and Malondialdehyde between the DOW-supplemented group and the CON group. Sequencing of rumen metagenome revealed that dietary supplementation with 20% DOW significantly affected the microbial composition and function and increased the richness and diversity of rumen microbiota and relative abundance of phylum Verrucomicrobia, Planctomycetes, Fibrobacteres, Chloroflexi, Actinobacteria, and Acidobacteria and species Ruminococcaceae_bacterium, Clostridiales_bacterium_NK3B98, Clostridiales_bacterium, and Clostridia_bacterium. It was concluded that supplementing the weaned lamb’s ration with DOW increased the immune response and antioxidant capacity in a dose-dependent manner. Meanwhile, dietary supplementation with 20% DOW modulated the composition of rumen microbiome function by increasing Ruminococcaceae_bacterium and Clostridiales_bacterium with improving the polysaccharide hydrolase activity in the rumen.

Domestic Cooking Affects the Prebiotic Performances of Chinese Yam

The appropriate domestic cooking methods can retain and protect the biological properties of foods well. Thus, the objective of this study was to unravel the effect of different cooking methods on the microbiota modulatory properties of yam and their non-starch polysaccharides by an in vitro simulated digestion and fermentation model. The results showed that different cooking processes led to different changes in polysaccharide content. The polysaccharide content of yam increased by 21.3~108.2% or decreased by 12.0% compared with that of raw yam. Additionally, the soluble polysaccharides contents in all cooked yam samples significantly increased by 16.85~119.97% after in vitro digestion. The regulation of whole-yam digesta on gut microbiota was partly related with yam polysaccharides. Both yam and yam polysaccharide fermentation appeared to promote beneficial bacteria, such as Bifidobacteria, Bacteroides spp. and Megasphaera and suppressed bacterial pathogens such as Ruminococcusforques and Escherichia-Shigella. Household cooking significantly influenced the prebiotic performances of yam and yam polysaccharides by changing the heat-sensitive microbial substrates and their physiology properties. According to our results, normal-pressure steaming and normal-pressure boiling processes can retain the microbiota modulatory effects of Chinese yam.

Dioscin Regulating Bone Marrow Apoptosis in Aplastic Anemia

Background

Aplastic anemia (AA), a disease of bone marrow failure, is caused by CD8⁺T mediated apoptosis of hematopoietic cells. However, traditional immunosuppressive therapy (IST) has severe liver and kidney toxicity and even cannot achieve the expected therapeutic effect in some patients.

Purpose

Our study is aimed to investigate the effect and mechanism of dioscin (DNS) for treating AA.

Methods

Briefly, we established and evaluated the AA mouse model, DNS and positive control drugs were used for intervention treatment. After 14 days of intervention, femoral bone marrow pathology, bone marrow mononuclear cells (BMMCs) apoptosis rate, bone marrow CD34+ cell surface Fas (CD95) expression and Fas signaling pathway key proteins were detected.

Results

After the establishment of the AA mouse model, the number of peripheral blood cells including granulocytes, erythrocytes, hemoglobin, platelets and reticulocytes in the AA group model was significantly decreased compared with the group control (P < 0.01). The degree of bone marrow hyperplasia in the sternum and femur is extremely low. After different drug interventions, compared with the group model, the number of peripheral blood cells in the AA mice rebounded significantly in group DNS (P < 0.01). Not only that the apoptosis rate of BM-MCs decreased (P < 0.01), meanwhile, the CD95 molecule expressed on the CD34+ bone marrow cells had a significant decline (P < 0.01), and the expression level of the key proteins of Fas signaling pathway was also significantly decreased (P < 0.01).

Conclusion

DNS recovered the peripheral pancytopenia and bone marrow failure in AA mice. DNS reduced the key protein of Fas signaling pathway level to inhibit apoptosis of bone marrow cells to treat AA.

Dioscin promotes autophagy by regulating the AMPK-mTOR pathway in ulcerative colitis

BACKGROUND

Dioscin is reported to alleviate the dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) in mice. Autophagy plays an anti-inflammatory role in UC. We herein aimed to explore the biological functions of dioscin in autophagy in UC.

METHODS

To explore the effects of dioscin on UC progression, a DSS-induced mouse model of UC was established. Body weight, disease activity index and macroscopic damage index scores were recorded for seven days. Hematoxylin & Eosin (HE) staining was used to stain colon sections and an BX53 microscope was prepared to observe pathological changes. The activities of glutathione, superoxidative dismutase, and malondialdehyde were determined by commercially available kits. Western blotting was performed to measure the protein levels of p-AMPK/AMPK, p-mTOR/mTOR and autophagy-related genes.

RESULTS

The DSS-induced colitis and oxidative stress in mice were ameliorated after dioscin treatment. Dioscin promoted the phosphorylation of AMPK to inhibit mTOR activation and facilitated autophagy in DSS-induced mice model of UC.

CONCLUSION

Dioscin promotes autophagy by promoting the phosphorylation of AMPK to inhibit mTOR activation in ulcerative colitis.

Anti-neuroinflammatory activity of 6,7-dihydroxy-2,4-dimethoxy phenanthrene isolated from Dioscorea batatas Decne partly through suppressing the p38 MAPK/NF-κB pathway in BV2 microglial cells

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Dioscorea batatas Decne (called Chinses yam) widely distributed in East Asian countries including China, Japan, Korea and Taiwan has long been used in oriental folk medicine owing to its tonic, antitussive, expectorant and anti-ulcerative effects. It has been reported to have anti-inflammatory, antioxidative, cholesterol-lowering, anticholinesterase, growth hormone-releasing, antifungal and immune cell-stimulating activities.

AIM OF THE STUDY

Neuroinflammation caused by activated microglia contributes to neuronal dysfunction and neurodegeneration. In the present study, the anti-neuroinflammatory activity of 6,7-dihydroxy-2,4-dimethoxy phenanthrene (DHDMP), a phenanthrene compound isolated from Dioscorea batatas Decne, was examined in microglial and neuronal cells.

MATERIALS AND METHODS

A natural phenanthrene compound, DHDMP, was isolated from the peel of Dioscorea batatas Decne. The anti-neuroinflammatory capability of the compound was examined using the co-culture system of BV2 murine microglial and HT22 murine neuronal cell lines. The expression levels of inflammatory mediators and cytoprotective proteins in the cells were quantified by enzyme-linked immunosorbent assay and Western blot analysis.

RESULTS

DHDMP at the concentrations of ≤1 μg/mL did not exhibit a cytotoxic effect for BV2 and HT22 cells. Rather DHDMP effectively restored the growth rate of HT22 cells, which was reduced by co-culture with lipopolysaccharide (LPS)-treated BV2 cells. DHDMP significantly decreased the production of proinflammatory mediators, such as nitric oxide, tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, and cyclooxygenase-2 in BV2 cells. Moreover, DHDMP strongly inhibited the nuclear translocation of nuclear factor κB (NF-κB) and phosphorylation of p38 mitogen-activated protein kinase (MAPK) in BV2 cells. The compound did not affect the levels and phosphorylation of ERK and JNK. Concurrently, DHDMP increased the expression of heme oxygenase-1 (HO-1), an inducible cytoprotective enzyme, in HT22 cells.

CONCLUSIONS

Our findings indicate that DHDMP effectively dampened LPS-mediated inflammatory responses in BV2 microglial cells by suppressing transcriptional activity of NF-κB and its downstream mediators and contributed to HT22 neuronal cell survival. This study provides insight into the therapeutic potential of DHDMP for inflammation-related neurological diseases.

Dioscin: A review on pharmacological properties and therapeutic values

Dioscin has gained immense popularity as a natural, bioactive steroid saponin, which offers numerous medical benefits. The growing global incidence of disease-associated morbidity and mortality continues to compromise human health, facilitating an increasingly urgent need for nontoxic, noninvasive, and efficient treatment alternatives. Natural compounds can contribute vastly to this field. Over recent years, studies have demonstrated the remarkable protective actions of dioscin against a variety of human malignancies, metabolic disorders, organ injuries, and viral/fungal infections. The successful usage of this phytocompound has been widely seen in medical treatment procedures under traditional Chinese medicine, and it is becoming progressively prevalent worldwide. This review provides an insight into the wide spectrum of pharmacological activities of dioscin, as reported and compiled in recent literature. The various novel approaches and applications of dioscin also verify the advantages exhibited by plant extracts against commercially available drugs, highlighting the potential of phytochemical agents like dioscin to be further incorporated into clinical practice.

Effects of the polysaccharides extracted from Chinese yam (Dioscorea opposita Thunb.) on cancer-related fatigue in mice

The aim of this study was to investigate the anti-fatigue activity of Chinese Yam polysaccharides (CYPs). The structural characterization of CYPs was conducted using Fourier transform-infrared spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography-light scattering-refractive index, and ion chromatography. The weight-loaded swimming capability, behavior performance, tumor growth, content of adenosine triphosphate (ATP), and biochemical markers of CYP in a cancer-related fatigue mouse model were tested. The results showed that CYP is a mixture with an average M_w of 75.57 kDa and is mainly composed of rhamnose, glucuronic acid, glucose, galactose, and arabinose with a molar ratio of 0.01 : 0.06 : 1.00 : 0.17 : 0.01. CYP increased the exhausting swimming time, which was decreased in the cisplatin (DDP) control group and the model group. CYP also increased the content of ATP in musculus gastrocnemius, which was down-regulated by DDP; the DDP had significantly enhanced the contents of interleukin-1β (IL-lβ), malondialdehyde (MDA), blood urea nitrogen (BUN) and lactic dehydrogenase (LDH) and inhibited the activity of superoxide dismutase (SOD) in the muscle. Administration of CYP decreased the levels of IL-lβ, MDA, BUN and LDH, and up-regulated the SOD activity. The DDP + CYP group presented a decreased tumor volume and a lower tumor weight as compared with the model group. Moreover, the mice in the CYP or DDP + CYP groups had heavier body weights than the mice in the model group and DDP group. These results suggest that CYP should improve cancer-related fatigue via the regulation of inflammatory responses, oxidative stress and increase in energy supplementation.

Dioscin prevents DSS-induced colitis in mice with enhancing intestinal barrier function and reducing colon inflammation

Dioscin is a natural steroid saponin derived from plants of the genus Dioscoreaceae. Previous studies have proved its effects of antibacterial, anti-inflammatory and hypolipidemic. In this study, our aim was to explore the protective effect and preliminary mechanism of Dioscin on dextran sulfate sodium (DSS)-induced colitis in mice. The results showed that Dioscin reduced DSS-induced disease activity index (DAI) increase, colon length shortening and colon pathological damage. In addition, Dioscin reduced excessive inflammation by reversing the cytokines levels, reducing intestinal macrophage infiltration and promoting macrophage polarization to M2 phenotype. At the same time, Dioscin maintained the intestinal barrier function by increasing the expression of zonula occludens-1 (ZO-1), occludin and mucin (Muc)-2. Moreover, Dioscin inhibited NF-κB, MAPK signaling and nucleotide oligomerization domain-like receptor family pyrin domain ontaining 3(NLRP3) inflammasome pathway in DSS-induced colitis. These results suggest that Dioscin is a competent candidate for ulcerative colitis (UC) therapy in the future.

Evaluation of the in vitro and in vivo genotoxicity of a Dioscorea Rhizome water extract

Dioscorea Rhizome is commonly used in traditional herbal medicines for the treatment of diabetes, hyperthyroidism, liver damage, neuropathy, and asthma. Here, we investigated the genotoxicity potential of D. Rhizome water extract (DRWE) using three standard battery systems in accordance with the test guidelines of the Organisation for Economic Cooperation and Development and Ministry of Food and Drug Safety as well as the principles of Good Laboratory Practice. A bacterial reverse mutation test (Ames test) was performed using the direct plate incorporation method in the presence or absence of a metabolic activation system (S9 mixture). The tester strains used included four histidine auxotrophic strains of Salmonella typhimurium, TA100, TA1535, TA98, and TA1537, along with a tryptophan auxotrophic strain of Escherichia coli, WP2 uvrA. An in vitro chromosome aberration test was performed using CHL/IU cells originally derived from the lung of a female Chinese hamster in the presence or absence of the S9 mixture. An in vivo mouse bone marrow micronucleus test was performed using male ICR mice. The micronucleus was confirmed after observation of the micro-nucleated polychromatic. The Ames test showed that DRWE did not induce gene mutations at any dose level in any of the tested strains. Additionally, DRWE did not result in any chromosomal aberrations specified in the in vitro chromosomal aberration and in vivo micronucleus tests. These results showed that DRWE exhibited neither mutagenic nor clastogenic potential in either the in vitro or in vivo test systems.

Influence of Lactic Acid Bacteria Fermentation on Physicochemical Properties and Antioxidant Activity of Chickpea Yam Milk

This study aimed to evaluate the influence of lactic acid bacteria fermentation on the physicochemical properties and antioxidant activity of chickpea yam milk. Four groups of chickpea milk were prepared through fermentation with lactic acid bacteria for quality and functionality improvement. Results indicate that the polysaccharide content of four samples declines during the fermentation process, and their infrared spectrums are similar with a slight difference in the transmittances of some characteristic bands. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles of four samples with 24 h fermentation showed a band disappearance in the range of 94.3 KDa and generation of many small-molecule peptides, revealing the protein degradation during fermentation. The moderate enzymatic hydrolysis had no adverse effect on the texture and color of the samples. A substantial increase in DPPH, ABTS radical scavenging rates, and FRAP value was observed after 12 h fermentation, especially the CPBY sample. The present results indicate that lactic acid bacteria fermentation can be used to improve the physicochemical properties of samples and enhance their antioxidant activity.

Characterization and antibacterial activity of edible films based on carboxymethyl cellulose, Dioscorea opposita mucilage, glycerol and ZnO nanoparticles

The edible films composed ofcarboxymethyl cellulose (CMC), glycerol, mucilage from Chinese yam (DOM)and ZnO nanoparticles (ZnO-NPs), were prepared by a casting method. To evaluate the applicability for food packaging, prepared films were characterised morphological, physical, rheological, mechanical and barrier properties, performed FT-IR, thermal analysis, and finally investigated the antibacterial activity and acute oral toxicity of films. The surface of films presented irregular arrangement with nanoparticles combined in the networks, suggesting the best "CMC to DOM weight ratio" of approximately 1:1 could provide a smooth surface. The films with 2.0 g ZnO-NPs presented antibacterial effects against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. With the increase of DOM, the antibacterial rate dropped at 400 and 450 μL/mL. The film-forming solutions with higher ZnO-NPs content display shear-thinning properties and liquid-like behaviour. The edible films have a great potential to be used in application in food packaging.

Additional Benefit of Chinese Medicine Formulae Including Dioscoreae rhizome (Shanyao) for Diabetes Mellitus: Current State of Evidence

Background

Chinese medicine has been used to treat diabetes symptoms for thousands of years. Dioscoreae rhizome or Shanyao is a Chinese medicinal herb that is routinely used in the treatment of diabetes mellitus (DM).

Objective

The purpose of this study is to evaluate the evidence of the added benefits and safety of herbal formulae containing Shanyao in clinical studies and the possible mechanisms of Shanyao in the prevention and treatment of DM in experimental studies.

Methods

We searched nine databases for randomized controlled trials (RCTs) that included Shanyao in the formulae in the treatment of type 2 DM. Furthermore, experimental studies on the prevention and treatment of DM by Shanyao in English- and Chinese-language databases were identified.

Results

Fifty-three moderate quality RCTs with herbal formulae containing Shanyao were identified. Results from meta-analysis indicated that Shanyao alone or formulae containing Shanyao in addition to conventional treatments could benefit people with type 2 DM in lowering blood glucose, blood lipids and reducing insulin resistance. Moreover, adverse events were significantly lower in the CHM plus conventional group than those in the conventional group. Shanyao may exert the benefit through various mechanisms including inhibition of α-glucosidase and DPP-IV activity, increase of endogenous GLP-1 and immune regulating activities.

Conclusion

Evidence from this review suggested that there appeared to be added clinical benefits associated with the use of Shanyao for DM, whether as a food supplement or as a CHM combined with hypoglycemic agents with a good safety profile.

Development of high-resolution DNA barcodes for Dioscorea species discrimination and phylogenetic analysis

The genus Dioscorea is widely distributed in tropical and subtropical regions, and is economically important in terms of food supply and pharmaceutical applications. However, DNA barcodes are relatively unsuccessful in discriminating between Dioscorea species, with the highest discrimination rate (23.26%) derived from matK sequences. In this study, we compared genic and intergenic regions of three Dioscorea chloroplast genomes and found that the density of SNPs and indels in intergenic sites was about twice and seven times higher than that of SNPs and indels in the genic regions, respectively. A total of 52 primer pairs covering highly variable regions were designed and seven pairs of primers had 80%-100% PCR success rate. PCR amplicons of 73 Dioscorea individuals and assembled sequences of 47 Dioscorea SRAs were used for estimating intraspecific and interspecific divergence for the seven loci: The rpoB-trnC locus had the highest interspecific divergence. Automatic barcoding gap discovery (ABGD), Poisson tree processes (PTP), and generalized mixed Yule coalescence (GMYC) analysis were applied for species delimitation based on the seven loci and successfully identified the majority of species, except for species in the Enantiophyllum section. Phylogenetic analysis of 51 Dioscorea individuals (28 species) showed that most individuals belonging to the same species tended to cluster in the same group. Our results suggest that the variable loci derived from comparative analysis of plastid genome sequences could be good DNA barcode candidates for taxonomic analysis and species delimitation.

Recent Advances in the Pharmacological Activities of Dioscin

Dioscin is a typical saponin with multiple pharmacological activities. The past few years have seen an emerging interest in and growing research on this pleiotropic saponin. Here, we review the emerging pharmacological activities reported recently, with foci on its antitumor, antimicrobial, anti-inflammatory, antioxidative, and tissue-protective properties. The potential use of dioscin in therapies of diverse clinical disorders is also discussed.

Chinese yam (Dioscorea opposita Thunb.) alleviates antibiotic-associated diarrhea, modifies intestinal microbiota, and increases the level of short-chain fatty acids in mice

Antibiotic-associated diarrhea (AAD) is a common adverse effect of antibiotic treatment. The study was to evaluate effects of Chinese yam (Dioscorea opposita Thunb.) on AAD, and changes of intestinal microbiota and short-chain fatty acids (SCFA). AAD model was established using Balb/c mice by gavage with ampicillin for 5 days, followed by a 10-day administration of low, medium, and high dosage of Chinese yam, containing allantoin (4.35 mg/g) and polysaccharides (85.51 mg/g). The results showed that Chinese yam accelerated the recovery from acute diarrhea, reverse AAD-induced body weight loss and cecal enlargement. The high-dosage Chinese yam increased probiotic Bifidobacteria and Lactobacilli by 47% and 21% and decreased potential pathogen Enterococcus and Clostridium perfringens by 8% and 27% on day 15 (P < .05). Bacterial community analysis revealed that Chinese yam contributed to repair the ampicillin-induced intestinal microbiota disorder, enrich the abundance of Bacteroides spp. and Clostridium spp. Additionally, Chinese yam supplementation increased the production of SCFA.

Shen-ling-bai-zhu-san, a spleen-tonifying Chinese herbal formula, alleviates lactose-induced chronic diarrhea in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Shen-ling-bai-zhu-san (SLBZS) was firstly documented in ancient Chinese medical works "Tai Ping Hui Min He Ji Ju Fang" in Song-dynasty. It has been widely used for treating gastrointestinal disorders such as diarrhea with poor appetite for about 900 years. The present study is to observe the effects of SLBZS on high lactose diet-induced chronic diarrhea.

MATERIALS AND METHODS

Rats were subjected to a high lactose diet to induce chronic diarrhea, which were then administrated with SLBZS or smecta. General symptom, body weight, food consumption, water intake and fecal fluid content were recorded every day. The intestinal absorption function was determined by d-xylose uptake assay. The ultrastructures of intestine segments including jejunum, ileum, proximal and distal colon were observed by transmission electron microscopy. Additionally, sodium transport proteins including γ-epithelial sodium channel (ENAC-γ) and sodium/potassium-transporting ATPase subunit alpha-1 (ATP1A1) in distal colon were detected by immunohistochemistry and western blotting.

RESULTS

Diarrheal rats produced watery or loose, sticky feces, and presented inactiveness and grouping. A high lactose diet caused a significant decline in body weight, serum d-xylose level as well as food consumption rather than water intake. In contrast, general symptoms were improved to a certain extent and body weight loss was alleviated in the rats treated by SLBZS for one week. Fecal fluid content in diarrheal rats treated by SLBZS presented a gradual decrease trend with about 55% in the end, which was significantly less than the model group with about 81%. Meanwhile, SLBZS significantly improved the serum d-xylose level and reversed abnormal changes of tight junctions and microvilli in intestine. Additionally, SLBZS significantly modulated the abnormal expressions of ENAC-γ and ATP1A1 in distal colon of diarrheal rats.

CONCLUSIONS

These findings suggested that SLBZS exhibited ameliorating effects against lactose-induced diarrhea, which might be attributed to its modulations on intestinal absorption function as well as mucosal ultrastructure.

Impact of plant extracts upon human health: A review

With the increase in evidences directly linking diet and health, several foodstuffs, such as phenolic rich fruits and vegetables, have emerged as possessing potential health benefits. Plants, given their fiber and phenolic content (and their intrinsic biological potential), have long been considered as contributing to health promotion. Therefore, the present work aimed to review the existing evidences regarding the various potential benefits of plant extracts' and plant extract-based products' consumption, with emphasis on in vivo works and epidemiological studies whenever available. Overall, the information available supports that, while there are indications of the potential benefits of plant extracts' consumption, further human-based studies are still needed to establish a true cause-effect.

Protective Effects of Dioscorea batatas Flesh and Peel Extracts against Ethanol-Induced Gastric Ulcer in Mice

Gastric ulcer is a major digestive disorder and provoked by multifactorial etiologies, including excessive alcohol consumption. In this study, we examined the gastroprotective effect of aqueous and ethanolic extracts of Dioscorea batatas Decne (DBD; commonly called Chinese yam) flesh or peel against acidified ethanol-induced acute gastric damage in mice. Our findings demonstrated that oral supplementation of aqueous or ethanolic extracts of DBD flesh or peel before ulcer induction was significantly effective in macroscopically and histologically alleviating ethanol-induced pathological lesions in gastric mucosa, decreasing the plasma levels of inflammatory mediators, such as nitric oxide and interleukin-6, attenuating the gastric expression of cyclooxygenase-2, and increasing the gastric content of prostaglandin E₂. In particular, pretreatment with the flesh extract prepared in 60% ethanol prominently decreased the expression of biomarkers of oxidative stress, including the plasma levels of 8-hydroxy-2-guanosine and malondialdehyde, and restored heme oxygenase-1 expression and superoxide dismutase activity in the stomach. Overall, these findings suggest that the oral supplementation with DBD extract, especially flesh ethanol extract, prior to excessive alcohol consumption, may exert a protective effect against ethanol-induced gastric mucosal damage in vivo, presumably through the activation of the antioxidant system and suppression of the inflammatory response.

Effects of Rhizome Extract of Dioscorea batatas and Its Active Compound, Allantoin, on the Regulation of Myoblast Differentiation and Mitochondrial Biogenesis in C2C12 Myotubes

With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of Dioscorea batatas (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.

Impact of Qi-invigorating traditional Chinese medicines on intestinal flora: A basis for rational choice of prebiotics

According to the theory of traditional Chinese medicine (TCM), Qi (vital energy) is regarded as a driving force of biological activities in human body, including both nutrient substances and organ functions. Qi-invigorating TCMs are widely used to treat various symptoms and disorders, such as fatigue, obesity, immunosuppression, intestinal flora imbalance, and gastrointestinal diseases, in which Qi is considered to be reduced or depleted. Interestingly, abundant clinical evidences suggest that these disorders are associated with the alternation of intestinal flora, which directly affects disease status. Herein we review the interaction between gut microbiota and Qi-invigorating TCMs under healthy and disease conditions and discuss the mechanisms of action and applications of Qi-invigorating TCMs in enhancing health status through microbial alternation. A better understanding of the role of Qi-invigorating TCMs in modulating microbial composition and the association between intestinal microbiota and diseases would help reveal the clinical consequences of microbiota alteration and explore opportunities to harness this symbiotic relationship to improve public health.

Hepatic anti-inflammatory effect of hexane extracts of Dioscorea batatas Decne: Possible suppression of toll-like receptor 4-mediated signaling

The hepatic anti-inflammatory potential of hexane extracts of Dioscorea batatas Decne edible part (EDH-1e) and bark (EDH-2b) were investigated in Western-type diet-fed apolipoprotein E null [ApoE (-/-)] mice and HepG2 cells. EDH-1e and EDH-2b suppressed the increased levels of tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, transforming growth factor beta 1 (TGF-β1), vascular cell adhesion protein 1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1), and reduced infiltration of monocytes into liver tissue. The protein levels of Toll-like receptor 4 (TLR4) were also downregulated by EDH-1e and EDH-2b treatment as were the levels of activator protein 1 (AP-1), c-fos, and c-jun in the livers from Western-type diet-fed ApoE (-/-) mice and in lipopolysaccharide-stimulated HepG2 cells. Taken together, EDH-1e and EDH-2b attenuated hepatic inflammation and fibrosis via suppression of the TLR4-AP1-mediated signaling pathway.

Anti-angiogenic effect of total saponins of Rhizoma Dioscorea nipponica on collagen induced-arthritis in rats

Rheumatoid arthritis (RA) is a common chronic autoimmune and incurable disease. The aim of the present study was to investigate the therapeutic effect and mechanism of the total saponins of Rhizoma Dioscorea nipponica (TSRDN) in RA. A collagen induced-arthritis (CIA) rat model was established. CIA rats were randomly divided into three groups and lavaged with an equal volume of solvent (CIA group), TSRDN (25 mg/kg/day, RDN group) and tripterygium (TP; 12 mg/kg/day, TP group) for 21 days, respectively. Normal rats served as a control group. Hematoxylin-eosin (HE) staining was used to observe the histopathological injury of synovial tissues. The level of CD31, which used for marking and counting, micro vessel density (MVD) and the expression levels of vascular endothelial growth factor (VEGF) and signal transducer and activator of transcription 3 (STAT3) were detected by immunohistochemical analysis. Additionally, the DNA-binding activity of nuclear factor-κB (NF-κB) was determined using an ELISA kit. HE staining showed obvious synovial hyperplasia, inflammatory cell infiltration, pannus formation, cartilage and bone erosion in the CIA group rats. In addition, compared with control group, the level of MVD, the expression of VEGF and STAT3, and the DNA-binding activity of NF-κB were all increased in CIA group rat synovial tissue (all P<0.01); however, TSRDN or tripterygium were able to inhibit these changes (all P<0.01). It was speculated that TSRDN may prevent angiogenesis by inhibiting the expression of STAT3 and the DNA-binding activity of NF-κB p65, thereby potentially improving CIA.

Shenzhu Tiaopi granule combined with lifestyle intervention therapy for impaired glucose tolerance: a randomized controlled trial

OBJECTIVE

The purpose of the study was to evaluate the clinical effects of the Shenzhu Tiaopi granule (SZTP) combined with a lifestyle intervention in patients with impaired glucose tolerance (IGT), who also had a spleen deficiency and damp overabundance syndrome (SDDOS).

METHODS

After a one-month washout period, a total of 514 patients were randomly assigned to the control (lifestyle intervention) and experimental (SZTP plus lifestyle intervention) groups, with 257 patients in each group. Patients in the control group received the lifestyle intervention (diet and exercise) for 12 months, while the patients in the experimental group were treated with SZTP plus the lifestyle intervention for 12 months. The Traditional Chinese Medicinal (TCM) symptom scores were observed in each group before and after treatment; the conversion rates from IGT to diabetes mellitus (DM) were also measured.

RESULTS

Following 12 months of treatment, the conversion rate from IGT to DM in the experimental group was significantly lower than in the control group (8.52% vs. 15.28%, P<0.05). A significantly higher number of patients with IGT reverted to normal blood glucose levels in the experimental group than in the control group (42.15% vs. 32.87%, P<0.05). In addition, after following the treatment for 12 months, the TCM symptoms of patients in the experimental group were markedly alleviated, as compared to the control group (P<0.01).

CONCLUSION

The combination of SZTP and lifestyle intervention showed a reduction in the conversion from IGT to DM, and an increase in the conversion from IGT to normal blood glucose levels.

Influence of different particle processing on hypocholesterolemic and antiatherogenic activities of yam (Dioscorea pseudojaponica) in cholesterol-fed rabbit model

BACKGROUND

Nanoparticle processing is implicated in enhancing bioactive or nutritional compound release from raw foods. The aim of the present study was to evaluate whether different particle processing might affect the lipid-lowering activity of Dioscorea pseudojaponica (DP) and to investigate whether DP could be a potential functional food for prevention of atherogenesis. Its possible molecular mechanisms were also evaluated.

RESULTS

The results indicated that 50 mesh-size DP (50 mesh DP) particles exhibited stronger effects than nanoscale DP (nano DP) particles in terms of lowering the level of serum cholesterol as well as reducing the extent of fatty liver and aortic fatty streak. Moreover, both DP particle types, particularly 50 mesh DP, significantly activated AMPK (5'-adenosine monophosphate-activated protein kinase) and deactivated ACC (acetyl-CoA carboxylase), as demonstrated by the increased levels of both enzymes in their phosphorylated form. Coincidently, high-performance liquid chromatography (HPLC) analysis showed a higher content (P < 0.01) of dioscin, a known lipid-lowering compound, in 50 mesh DP than in nano DP.

CONCLUSION

These results suggest that improper processing conditions will lead to the decomposition of bioactive components in yam. They also demonstrate for the first time that the lipid-lowering mechanisms of DP may occur through the AMPK-ACC pathway.

Anti-proliferation and anti-invasion effects of diosgenin on gastric cancer BGC-823 cells with HIF-1α shRNAs

Drug resistance is a major factor for the limited efficacy of chemotherapy in gastric cancer treatment. Hypoxia-inducible factor-1α (HIF-1α), a central transcriptional factor in hypoxia, is suggested to participate in the resistance. Here, we identified a hypoxia-mimic (cobalt chloride) sensitive gastric cell line BGC-823 to explore whether diosgenin, an aglycone of steroidal saponins, can inhibit cancer cell invasion and survival of solid tumor in a hypoxic mimic microenvironment. We have shown that diosgenin is a potent candidate for decreasing the ability of invasion and survival in cobalt chloride treated BGC-823 cells. In addition, when combined with HIF-1α specific short hairpin RNA (shRNA), diosgenin can inhibit BGC-823 cells more effectively. The anti-invasion role of diosgenin may be related to E-cadherin, integrinα5 and integrin β6. These results suggest that diosgenin may be a useful compound in controlling gastric cancer cells in hypoxia condition, especially when combined with down-regulated HIF-1α.

Anti-inflammatory activity of 6-hydroxy-2,7-dimethoxy-1,4-henanthraquinone from tuberous roots of yam (Dioscorea batatas) through inhibition of prostaglandin D₂ and leukotriene C₄ production in mouse bone marrow-derived mast cells

6-Hydroxy-2,7-dimethoxy-1,4-phenanthraquinone (PAQ) isolated from the tuberous roots of Yam (Dioscorea batatas) inhibited cyclooxygenase-2 (COX-2) and cyclooxygenase-1 (COX-1) dependent prostaglandin D(2) (PGD(2)) generation in mouse bone marrow-derived mast cells in a concentration-dependent manner with IC(50) values of 0.08 μM and 0.27 μM, respectively. In the Western blotting with specific anti-COX-2 antibodies, the decrease of the quantity of PGD(2) was accompanied by a decrease in the COX-2 protein level. But PAQ did not affect COX-1 protein level. In addition, this compound inhibited 5-lipoxygenase (5-LOX) dependent production of leukotriene C(4) in a dose-dependent manner, with an IC(50) of 0.032 μM. These results demonstrate that PAQ has a dual COX-2/5-LOX inhibitory activity. This compound also inhibited the degranulation reaction in a dose-dependent manner with an IC(50) of 2.7 μM. Thus, these results suggest that PAQ may be useful in regulating mast cell-mediated inflammatory diseases.

Review of the effects of the traditional Chinese medicine Rehmannia Six Formula on diabetes mellitus and its complications

Rehmannia Six Formula (RF) is a formula that is commonly used in Traditional Chinese Medicine to treat patients with diabetes. A literature search was performed in PubMed for the years 2000-2009 using the key words RF, Rehmannia glutinosa, Fructus Corni, Dioscorea sp. (D. alata, D. opposita, D. batatas), Poria cocos, Alisma sp. (A. orientalis, A. plantago aquatica), and Paeonia suffruticosa/Cortex Moutan. On the basis of the publications found, RF appears to have beneficial effects on blood glucose, neuropathy, and nephropathy. There is also evidence of anti-inflammatory and antioxidant effects. Although there are many studies on compounds extracted from individual herbs, there are not many studies on RF as a whole. Because there is preliminary evidence that RF may be a useful supplement for the prevention of diabetic complications, clinical studies are warranted. For future clinical studies, it is recommended that details are provided regarding the preparation of RF and that the ratio of the individual components in RF is standardized so that results across studies can be compared.

Effects of dietary supplementation of Chinese medicinal herbs on polymorphonuclear neutrophil immune activity and small intestinal morphology in weanling pigs

The purpose of this study was to evaluate the effects of dietary Chinese medicinal herbs (CMH) supplementation composed of Panax ginseng, Dioscoreaceae opposite, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube and Platycodon grandiflorum, on the performance, intestinal tract morphology and immune activity in weanling pigs. Two hundred and forty weaned pigs were assigned randomly to four dietary groups including the negative control (basal diet), 0.1% CMH, 0.3% CMH and 0.114% antibiotic (Chlortetracycline calcium Complex, Sulfathiazole and Procaine Penicillin G) supplementation groups for a 28-day feeding trial. Results indicated that both CMH supplementation groups had a better gain and feed/gain than control group (CT) during the first 2 weeks of the experimental period. The 0.3% CMH had a significant decrease in the diarrhoea score in first 10 days of experimental period when compared with other groups. The CMH supplementation groups had a higher villous height, increased lactobacilli counts in digesta of ileum and decreased coliform counts in colon compared with CT. The immune activities of polymorphonuclear leucocytes (PMNs), including the respiratory burst and Salmonella-killing ability, were significantly enhanced in CMH supplementation groups at day 7 of experiment period. The CMH and antibiotic supplementations increased the nutrient digestibility such as dietary dry matter, crude protein and gross energy in weanling pigs. In conclusion, the dietary CMH supplementation improved intestinal morphology and immune activities of PMNs, thus giving rise to nutrient digestibility and reduce diarrhoea frequency in weanling pigs.

Yam contributes to improvement of glucose metabolism in rats

To investigate whether yam improves glucose metabolism, yam-containing diets were given to Wistar rats. In a short-term experiment, fasted-rats were given 1.0 g of a control and 20% yam-containing diets. At 60 min after start of the feeding, glucose level in the yam diet group was lower or tended to be lower than that in the control diet. Insulin levels at 30 min and 60 min were significantly lower than those in the control group. In a long-term experiment, a normal diet (N) or 25% high fat diets with (Y) or without 15% yam powder (HF) were given to rats for 4 weeks. At 4 weeks, in an oral glucose tolerance test, the area under the curve (AUC) of plasma glucose level was higher in the HF group than that in the N group, whereas those in the Y groups did not differ from that in the N group. Glycosylated hemoglobin levels had similar tendency to the AUCs. Plasma leptin levels in the Y groups were significantly higher than that in the N group. In conclusion, yam may contribute to improvement of glucose metabolism. Additionally, we speculated that leptin level is possibly involved in the insulin-response to yam diets.

Red mold dioscorea has a greater antihypertensive effect than traditional red mold rice in spontaneously hypertensive rats

The aim of this study is to investigate the antihypertensive effects of red mold rice (RMR) and red mold dioscorea (RMD) by low-dose oral administration to spontaneously hypertensive rats (SHRs). A single oral dose of 1-fold RMD (150 mg/kg) significantly (p < 0.05) decreased systolic blood pressure (SBP) and diastolic blood pressure (DBP) after 8 h of administration, but RMR showed no significant effect. During the chronic oral administration of 1-fold RMR (150 mg/kg), 0.5-fold RMD, 1-fold RMD, and 5-fold RMD to SHRs for 8 weeks, the increase of blood pressure was slowed significantly. The results indicated that only a 0.5-fold dose of RMD was able to significantly decrease both SBP and DBP. A 1-fold RMD showed a greater antihypertensive effect than 1-fold RMR, and both RMR and RMD can improve the vascular elastin structure remodeling. In comparison to RMR, RMD contained a higher amount of gamma-aminobutyric acid (GABA) and anti-inflammatory yellow pigments (monascin and ankaflavin). Moreover, RMD also exhibited higher angiotensin-I-converting enzyme (ACE) inhibitory activity than RMR. These results suggest that RMD has greater antihypertensive bioavailability.

Jamaican bitter yam sapogenin: potential mechanisms of action in diabetes

Sapogenin has been proposed to be the active component responsible for the beneficial effects of Jamaican bitter yam (Dioscorea polygonoides) in the management of diabetes. Most of the research activities on bitter yam have focused on the role sapogenin play in the management of diabetes. Changes in weight, activities of carbohydrate digestive and transport enzymes, alterations in the intestinal morphology, changes in blood lipids, reduction in lipid peroxidation and the prevention of liver damage associated with diabetes have all been attributed to bitter yam sapogenin supplementation. Also, the possible exploitation of bitter yam for nutraceutical/pharmaceutical purposes is based on the high saponin content. There are however, concerns about the beneficial claims of the findings especially with regard to the possible adverse effects that may accrue in the clinical applications. This review therefore provides an overview of the findings in this research area with a view to proposing the potential mechanisms whereby the supplement of bitter yam sapogenin extract exert its hypoglycemic and hypolipidemic properties and the probable adverse effects in diabetes mellitus.