Search Results (8)

Background/Objectives: Myocardial ischemia/reperfusion (I/R) injury remains a critical challenge in cardiovascular disease management. Although Chinese yam polysaccharides (CYPs), the primary bioactive macromolecules isolated from Dioscorea opposita Thunb, exhibit well-documented antioxidant and anti-inflammatory properties, their cardioprotective efficacy against acute I/R injury and the underlying multiscale mechanisms remain unexplored. This study investigated the protective effects of CYPs using an in vivo mouse model of myocardial I/R injury. Methods: An in vivo mouse model of myocardial I/R injury was used to evaluate the effects of 7-day prophylactic CYPs treatment (400 mg/kg). Echocardiographic and histological analyses were performed, and serum myocardial injury biomarkers, oxidative stress indicators, pro-inflammatory cytokines, mitochondrial ultrastructure, ATP bioenergetics, mitochondrial respiratory chain gene expression, and gut microbiota composition were assessed. Results: Echocardiographic and histological analyses revealed that CYPs pretreatment significantly ameliorated cardiac dysfunction, as indicated by increased LVEF from 28.98% to 57.68% and reduced myocardial infarct size by 36.73% compared with the I/R group and decreased serum myocardial injury biomarkers, including CK-MB, LDH, and LDH-1. Mechanistically, CYPs exerted robust cardioprotection by mitigating oxidative damage, with MDA levels reduced by 28.83% and SOD activity increased to 1.76-fold that of the I/R group, and suppressing the release of pro-inflammatory cytokines, including Tnf-α, Il-6, and Il-1β. Crucially, CYPs intervention preserved mitochondrial ultrastructure and ATP bioenergetics, and levels increased to 1.51-fold that of the I/R group and upregulated the expression of essential mitochondrial respiratory chain genes, including mt-Nd1, mt-Nd4l, mt-Cyb, mt-CoII, and mt-Atp6. Furthermore, 16S rRNA sequencing showed that CYPs treatment reshaped gut microbiota and elevated the relative abundance of anti-inflammatory and antioxidant beneficial genus Akkermansia. Conclusions: Collectively, these findings provide novel evidence that CYPs confer profound protection against myocardial I/R injury through a multitargeted network involving the restoration of mitochondrial homeostasis, attenuation of oxidative inflammation, and modulation of the gut microbiome, highlighting CYPs as a promising functional food-derived candidate for adjunctive therapy in ischemic heart disease. Full article

Background/Objectives: Parkinson’s disease (PD) is a progressive neurodegenerative disorder that poses a substantial threat to global human health. Yam (Dioscorea opposita Thunb.) is a traditional medicinal and edible plant that has long been used in Asia, Africa, and the Caribbean. Its major bioactive components, such as dioscin and polysaccharides, have been reported to exhibit neuroprotective effects; however, the impact of dietary yam on PD progression remains to be elucidated. Therefore, we sought to evaluate its neuroprotective potential and the underlying mechanisms in 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP)-induced PD mice. Methods: Mice received six-week dietary yam supplementation. Behavioral, histological, and neurochemical analyses were performed to assess motor function, dopaminergic neuron integrity, and dopamine levels. Gut microbiota and metabolic profiles were analyzed using 16S rRNA gene sequencing and non-targeted metabolomics. Transcriptomic sequencing and Western blot analysis of the substantia nigra pars compacta (SNc) were conducted to investigate molecular mechanisms, and integrative multi-omics analysis was applied to explore microbiota–metabolite–host interactions. Results: Yam supplementation improved motor function, preserved nigrostriatal dopaminergic neurons, and restored striatal dopamine levels in PD mice. Notably, yam was associated with the maintenance of intestinal homeostasis by strengthening barrier integrity and enriching beneficial taxa, including Ileibacterium, Lachnospiraceae NK4A136 group, and Blautia. Consistently, yam also elevated neuroprotective purines and amino acids, including inosine, xanthine, and succinic acid. At the molecular level, yam treatment modulated mitochondrial oxidative phosphorylation by increasing PGC-1α and COX7c expression, and reduced inflammasome-related neuroinflammatory signaling. Integrative modeling showed significant associations between yam-modulated genes and PD-related indices with microbiota and metabolites. Conclusions: These findings suggest that yam may represent a potential dietary strategy for alleviating PD-related neurodegeneration by modulating the microbiota–gut–brain axis. Full article

Yams are the edible subterranean rhizomes, or tubers, of plants from the genus Dioscorea. There are approximately 600 species of yam plants in the world, with more than 90 of these growing in East Asia. One particular species, Dioscorea opposita Thunb., is highly praised as “the Chinese yam”. This distinction arises from millennia of storied history, both as a nutritional food source and as a principal ingredient in traditional Chinese medicine. Among the many cultivars of Dioscorea opposita Thunb., Huai Shanyao has been widely regarded as the best. This review surveyed the historical background, physiochemical composition, applications as food and medicine, and research prospects for the Chinese yam. Modern science is finally beginning to confirm the remarkable health benefits of this yam plant, long-known to the Chinese people. Chinese yam promises anti-diabetic, anti-oxidative, anti-inflammatory, immunomodulatory, anti-hyperlipidemic, anti-hypertensive, anti-cancer, and combination treatment applications, both as a functional food and as medicine. Full article

The non-starch yam polysaccharides (YP) are the bioactive substances of edible yam, while Se is an essential nutrient for the human body. Whether a covalent conjugation of Se to YP might cause bioactivity change for the resultant selenylated YP in the intestine is still insufficiently studied, including the critical intestinal barrier function. In this study, two selenylated YP products, namely, YPSe-I and YPSe-II, with corresponding Se contents of 795 and 1480 mg/kg, were obtained by the reaction of YP and Na₂SeO₃ in the presence of HNO₃ and then assessed for their bioactivities to a cell model (i.e., rat intestinal epithelial IEC-6 cells). The results showed that YP, YPSe-I, and YPSe-II at 5–80 μg/mL dosages could promote cell growth with treatment times of 12–24 h. The three samples also could improve barrier integrity via increasing cell monolayer resistance and anti-bacterial activity against E. coli or by reducing paracellular permeability and bacterial translocation. Additionally, the three samples enhanced F-actin distribution and promoted the expression of the three tight junction proteins, namely, zonula occluden-1, occludin, and claudin-1. Meanwhile, the expression levels of ROCK and RhoA, two critical proteins in the ROCK/RhoA singling pathway, were down-regulated by these samples. Collectively, YPSe-I and, especially, YPSe-II were more potent than YP in enhancing the assessed bioactivities. It is thus concluded that this chemical selenylation of YP brought about enhanced activity in the cells to promote barrier integrity, while a higher selenylation extent of the selenylated YP induced much activity enhancement. Collectively, the results highlighted the important role of the non-metal nutrient Se in the modified polysaccharides. Full article

A novel hydrogel (DOP/PEI-PBA) based on the “three-component” reaction of 2-formylphenylboric acid (2-FPBA), the primary amine group of polyethyleneimine (PEI) and the cis-o-dihydroxy groups of Dioscorea opposita Thunb polysaccharide (DOP) was designed in this work. The hydrogel can be easily prepared by simply mixing the three reactants at room temperature. The hydrogel had dual responsiveness to glucose and pH, and can realize the controllable release of insulin. Moreover, the hydrogel combining insulin and DOP can inhibit the reactive oxygen species (ROS) level and malondialdehyde (MDA) content, and promote glucose consumption as well as the level of superoxide dismutase (SOD), in high-glucose-induced injury in HL-7702 cells, which reflects the synergistic effect of insulin and DOP to protect hepatocytes from oxidative stress at the same time. Further in vitro cytotoxicity studies showed that the hydrogel had good biocompatibility and no obvious toxicity to cells. These indicate that the prepared hydrogel (DOP/PEI-PBA) can be expected to be applied in the clinical treatment of insulin deficiency in diabetes. Full article

The immunomodulation of chemically selenylated polysaccharides has been attracting more attention recently, but the corresponding performance of the yam polysaccharides (YPS) with lower selenylation extent remains, thus far, unsolved. In this study, the YPS was selenylated with Na₂SeO₃ under acidic conditions generated by HNO₃ to reach two lower selenylation extents, yielding two selenylated YPSs, namely SeYPS-1 and SeYPS-2 with selenium contents of 715 and 1545 mg/kg, respectively. The results indicated that YPS, SeYPS-1, and SeYPS-2 all had in vitro immuno-modulation when using RAW 264.7 macrophages and murine splenocytes as cell models. In detail, the three polysaccharide samples at dose levels of 5–160 μg/mL showed insignificant cytotoxicity to the macrophages and splenocytes with cell exposure times of 12–24 h, because of the measured values of cell viability larger than 100%. However, Na₂SeO₃ at dose levels of 1.3–3.25 μg/mL mostly caused obvious cytotoxic effects on the cells, resulting in reduced cell viability values or cell death, efficiently. The results demonstrated that, compared with YPS, both SeYPS-1 and SeYPS-2 at a lower dose level (5 μg/mL) were more active at promoting phagocytosis activity, increasing the CD4⁺/CD8⁺ ratio of the T-lymphocyte sub-population in the murine splenocyte, improving cytokine secretion, including interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in the macrophages, or increasing interferon-γ secretion, but suppressing IL-4 production in the splenocytes. Consistently, SeYPS-2 has more potential than SeYPS-1 at exerting these assessed bioactivities in the cells. Thus, we conclude that a chemical modification of YPS using trace element Se at a lower selenylation extent could bring about higher immunomodulatory activity towards macrophages and splenocytes, while selenylation extent of YPS is a critical factor used to govern the assessed activity changes of YPS. Full article

Impacts of wheat flour substituted with various levels of Chinese yam (Dioscorea opposita Thunb.) flour (from 0% to 25%) on the dough rheological characteristics, gluten structure, baking performance, and antioxidant properties of bread were investigated. The water absorption increased significantly (p < 0.05), while development time and stability decreased remarkably (p < 0.05) as the proportion of yam flour increased. SEM results indicated that the addition of yam flour destroyed the gluten network structure in the dough. Fourier Transform Infrared Spectroscopy (FTIR) spectra showed that addition of yam flour decreased the content of α-helix and β-sheet in gluten. With the increase in the proportion of yam flour, the specific volume and overall acceptability decreased (p < 0.05) whereas the total phenolics content (TPC), polysaccharides content, total flavonoids content (TFC), allantoin content, The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capability, fractal dimension, and hardness increased (p < 0.05). Overall, breads made of wheat flour replacement with no more than 15% Guihuai number 2 yam flour were of a high quality and had more antioxidant properties. These showed that Guihuai number 2 had broad application prospects in baked products. Full article

A polysaccharide DOTP-80 from Dioscorea opposita Thunb was obtained by using the method of acid water-extraction and ethanol-precipitation. After being purified by chromatography, the structure characteristics of DOTP-80 were established. Based on the calibration curve obtained with standard dextrans, the molecular weight of the polysaccharide fraction DOTP-80 was calculated to be 123 kDa. The results of Infrared spectrum (FT-IR) indicated that the polysaccharide contained the α-configuration of sugar units. GC-MS analysis revealed that DOTP-80 was mainly composed of mannose and glucose. Alloxan-induced diabetic rats and mice models were developed to evaluate the in vivo hypoglycemic activity of the polysaccharide. The results indicated that a high dose DOTP-80 (400 mg/kg) had strong hypoglycemic activity. Moreover, DOTP-80 could increase the level of antioxidant enzymes (SOD) activity in alloxan-induced diabetic mice and stimulate an increase in glucose disposal in diabetic rats. Therefore, the polysaccharide DOTP-80 should be evaluated as a candidate for future studies on diabetes mellitus. Full article