Protective Mechanism of Polysaccharide ORP-1 Isolated from Oudemansiella raphanipes against Age-Related Cognitive Decline through the Microbiota-Gut-Brain Axis.

Age-related cognitive decline is primarily attributed to the progressive weakening of synaptic function and loss of synapses, while age-related gut microbial dysbiosis is known to impair synaptic plasticity and cognitive behavior by metabolic alterations. To improve the health of the elderly, the protective mechanisms of Oudemansiella raphanipes polysaccharide (ORP-1) against age-related cognitive decline are investigated. The results demonstrate that ORP-1 and its gut microbiota-derived metabolites SCFAs restore a healthy gut microbial population to handle age-related gut microbiota dysbiosis mainly by increasing the abundance of beneficial bacteria Dubosiella, Clostridiales, and Prevotellaceae and reducing the abundance of harmful bacteria Desulfovibrio, strengthen intestinal barrier integrity by abolishing age-related alterations of tight junction (TJ) and mucin 2 (MUC2) proteins expression, diminish age-dependent increase in circulating inflammatory factors, ameliorate cognitive decline by reversing memory- and synaptic plasticity-related proteins levels, and restrain hyperactivation of microglia-mediated synapse engulfment and neuroinflammation. These findings expand the understanding of prebiotic-microbiota-host interactions.

Polysaccharide ORP-1 isolated from Oudemansiella raphanipes ameliorates age-associated intestinal epithelial barrier dysfunction in Caco-2 cells monolayer.

Age-associated increase in intestinal permeability is known to relate with gut microbiota dysbiosis and loss of epithelial tissue integrity. To improve healthy aging and prevent age-associated chronic disabilities, the protective potential of polysaccharides from Oudemansiella raphanipes (ORP-1) against age-associated intestinal epithelial barrier dysfunction in d-galactose-induced Caco-2 cells monolayer was investigated. In-vitro results demonstrated that ORP-1 can restore a healthy gut microbial population to handle age-related gut microbiota dysbiosis mainly by facilitating the proliferation and adhesion of probiotics Lactobacillus acidophilus (L. acidophilus) and Bifidobacterium bifidum (B. bifidum) to compete with intestinal pathogenic Escherichia coli (E. coli) for ecological niches and nutrition. Meanwhile, ORP-1 strengthened the intestinal structural integrity primarily by abolishing the aggravation of apoptosis and the age-associated alterations of tight junction (TJ) proteins expression in intestine. These findings highlighted that ORP-1 could be a potential functional food component with preventive utility against age-associated intestinal barrier injury.

Characterization and immunomodulatory effect of an alkali-extracted galactomannan from Morchella esculenta.

In our continuous exploration for bioactive polysaccharides, a novel polysaccharide FMP-2 was isolated and purified from the fruiting bodies of Morchella esculenta by alkali-assisted extraction. FMP-2 had an average molecular weight of 1.09 × 106 Da and contained mannose, glucuronic acid, glucose, galactose, and arabinose in a molar ratio of 4.10:0.22:1.00:5.75:0.44. The backbone of FMP-2 mainly consisted of 1,2-α-D-Galp, 1,6-α-D-Galp, and 1,4-α-D-Manp, with branches of 1,4,6-α-D-Manp and 1,2,6-α-D-Galp. FMP-2 can stimulate phagocytosis and promote the secretion of NO, ROS, and cytokines like IL-6, IL-1ß, and TNF-α in RAW264.7 cells ranging from 25 to 400 µg/mL. FMP-2 had great repairing effect on the immune injury of zebrafish induced by chloramphenicol. The phagocytosis ability of zebrafish macrophages and the proliferation of neutrophils can be greatly enhanced by polysaccharide FMP-2 with concentrations from 50 to 200 µg/mL. These findings suggest that FMP-2 might be used as a potential immunomodulator in the food and pharmaceutical industries.

Reduction of 5-fluorouracil-induced toxicity by Sarcodon aspratus polysaccharides in Lewis tumor-bearing mice.

5-Fluorouracil (5-Fu) is an effective anticarcinogenic agent, however, continuous use of 5-Fu may cause severe side effects. The goal of this study was to investigate the effectiveness of Sarcodon aspratus polysaccharides (SATP) in alleviating 5-Fu-induced toxicity in Lewis tumor-bearing mice. Lewis tumor-bearing mice were treated with saline, SATP, 5-Fu or 5-Fu + SATP. The results indicated that compared to the 5-Fu group, the 5-Fu + SATP group showed effective amelioration of the liver, kidney and small intestine injury caused by 5-Fu and decreases in the levels of related biochemical indicators, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT) and urea nitrogen (BUN). Additionally, the combination therapy enhanced the quality of life and immune organ indexes of mice. Further mechanistic studies indicated that the 5-Fu + SATP group showed a decrease in hepatotoxicity caused by 5-Fu via a reduction in the levels of interleukin-1ß (IL-1ß), an increase in the expression of Bcl-2 and decreases in the expression of p-p38, p-JNK and Bax. Collectively, the results indicated that SATP could significantly alleviate the toxicity of 5-Fu in Lewis tumor-bearing mice and showed the hepatoprotective capability of SATP via its effect on the expression levels of inflammatory factors and components of the MAPK/P38/JNK pathway, which shows that it may be a potential adjuvant for the chemotherapeutic drug 5-Fu in cancer treatment.

Structural characterization and in vitro hypoglycemic activity of a glucan from Euryale ferox Salisb. seeds.

In this research, a polysaccharide fraction (EFSP-1) was obtained from the seeds of Euryale ferox Salisb. by DEAE sepharose FF and Superdex™ 75 gel chromatography. The average molecular weight (Mw) of EFSP-1 was 8.75 kDa. Monosaccharides composition analysis indicated that EFSP-1 was a glucan. The structure of EFSP-1 was characterized by analysis of FT-IR, GC-MS and NMR, which indicated that the backbone of EFSP-1 was mainly composed of (1→4)-α-D-Glcp with branches substituted at O-6 and terminated with T-α-D-Glcp. Moreover, the hypoglycemic effect of EFSP-1 was investigated by establishing insulin resistance HepG2 and 3T3-L1 cells. The results showed that EFSP-1 could increase glucose consumption by up-regulating the expression of GLUT-4 via activating PI3K/Akt signal pathway in IR cells. Hence, EFSP-1 could be a potential functional food to ameliorate insulin resistance for diabetes therapy.

Effect of polysaccharide FMP-1 from Morchella esculenta on melanogenesis in B16F10 cells and zebrafish.

Polysaccharides from Morchella esculenta are known to exhibit diverse bioactivities, while an anti-melanogenesis effect has been barely addressed. Herein, the anti-melanogenesis activity of a heteropolysaccharide from M. esculenta (FMP-1) was investigated in vitro and in vivo. FMP-1 had no significant cytotoxic effect on B16F10 melanoma cells as well as zebrafish larvae, but did reduce melanin contents and tyrosinase activities in both of them. Treatment with FMP-1 also effectively suppressed the expression of melanogenesis-related proteins, including MC1R, MITF, TRP-1 and TRP-2, through decreasing the phosphorylation of cyclic adenosine monophosphate response element-binding protein (CREB). Moreover, the mitogen-activated protein kinase (MAPK) pathway was observed mediating FMP-1's inhibitory effect against melanin production. Specifically, FMP-1 treatment markedly inhibited the activation of phosphorylation of p38 mitogen-activated protein kinase. These results suggested that FMP-1's inhibitory effect against melanogenesis is mediated by the inhibition of CREB and p38 signaling pathways, thereby resulting in the downstream repression of melanogenesis-related proteins and the subsequent melanin production. These data provide insight into FMP-1's potential anti-melanogenesis effect in food and cosmetic industries.

Polysaccharide isolated from Sarcodon aspratus induces RAW264.7 activity via TLR4-mediated NF-κB and MAPK signaling pathways.

Our previous report showed that the novel polysaccharide SAP isolated from the fruiting bodies of Sarcodon aspratus induced Hela cells apoptosis via mitochondrial dysfunction. In this study we found that SAP enhanced immunostimulatory activities of RAW264.7 cells, which was characterized by increased the production of nitric oxide (NO), reactive oxygen species (ROS), cytokines and phagocytic. However, SAP-induced macrophage activation was abolished when Toll-like receptor 4 (TLR4) signaling was blocked by anti-TLR4 antibodies. Moreover, according to the Western blot analysis and use of specific inhibitors against the MAPKs (mitogen-activated protein kinases) and NF-κB (nuclear factor-κB), we speculated that SAP activated RAW264.7 cells through TLR4-mediated activation of NF-κB and MAPKs pathways. Thus, Sarcodon aspratus is a potential immunomodulator that can be used as healthcare food.

Polysaccharide FMP-1 from Morchella esculenta attenuates cellular oxidative damage in human alveolar epithelial A549 cells through PI3K/AKT/Nrf2/HO-1 pathway.

Oxidative stress is considered to involve cell death in severe pulmonary diseases like idiopathic pulmonary fibrosis (IPF). Polysaccharide FMP-1 from Morchella esculenta can exert significant antioxidant activity. However, its effects on alveolar epithelial cells remain unperceived. Herein, the effects of FMP-1 against H2O2-induced oxidative damage in human alveolar epithelial A549 cells were investigated. FMP-1 could inhibit H2O2-induced cytochrome C and Caspase-3 release to prevent cell apoptosis via attenuation of MDA and ROS levels, and enhancement the enzymatic activities of SOD and T-AOC. Furthermore, the underlying molecular mechanisms were clarified. The phosphorylation of AKT and the nuclear translocation of Nrf2 were observed to be promoted by FMP-1 as well as the level of HO-1. These findings suggested that FMP-1 attenuate cellular oxidative stress through PI3K/AKT pathway, and FMP-1 could be explored as natural potential antioxidants to lower oxidative stress relevant to the progression of IPF.

Structural characterization and antioxidant activities of a novel polysaccharide fraction from the fruiting bodies of Craterellus cornucopioides.

A new polysaccharide fraction (CCPP-1) was obtained from Craterellus cornucopioides. CCPP-1 had an average molecular weight of 9.2 × 105 Da, which was mainly composed of mannose, glucose, xylose, arabinose, fructose in molar ratio of 0.7:0.05:0.18:1:0.05. Results of structural characterization revealed that the dominant linkage types of CCPP-1 were →3, 6)-Manp(1→, T-Araf, →4, 6)-Manp (1→, →5)-Araf (1→ and →3)-Araf (1→. Interesting, in vitro antioxidant activities assays showed that CCPP-1 possessed strong scavenging abilities on DPPH and ABTS radicals. The oxidative hemolysis induced by AAPH in mice erythrocytes was effectively reversed by incubation with CCPP-1. CCPP-1 significantly prevented AAPH-induced intracellular reactive oxygen species (ROS) generation. Moreover, CCPP-1 could significantly restore AAPH-induced increase of intracellular antioxidant enzyme glutathione peroxidase (GPx) and catalase (CAT) activities to normal level, as well as inhibit intracellular malondialdehyde (MDA) formation. Therefore, CCPP-1 could protect against AAPH-induced oxidative-stress in erythrocytes, which would be explored as naturally potential antioxidant agent applied in food and cosmetic fields.

Structural characterization, in vitro and in vivo antioxidant activities of a heteropolysaccharide from the fruiting bodies of Morchella esculenta.

This study aimed to investigate the structural features, in vitro and in vivo antioxidant activities of a heteropolysaccharide from the fruiting bodies of Morchella esculenta (FMP-1). FMP-1 had an average molecular weight of 4.7 × 103 Da and consisted of mannose, glucose and galactose. By methylation and NMR analysis, the backbone of FMP-1 was deduced to be made up of 1,4-linked Glcp and 1,6-linked Galp. Hydroxyl, DPPH and superoxide radicals could be efficiently scavenged by FMP-1, with IC50 values of 74.26, 119.32 and 161.49 µg/mL, respectively. Furthermore, FMP-1 could significantly protect zebrafish embryos against AAPH-induced oxidative damage. Decrease in malformations and mortalities was observed along with the reduction of ROS production, NO production and cell death. The protective effects were by decreasing MDA content and increasing SOD, CAT and GSH-Px levels. The current work provided a good suggestion of the potential utilization of FMP-1 as an attractive natural antioxidant.

A novel polysaccharide from the Sarcodon aspratus triggers apoptosis in Hela cells via induction of mitochondrial dysfunction.

BACKGROUND: Polysaccharides extracted from fungus that have been used widely in the food and drugs industries due to biological activities. OBJECTIVE: The objective of the present study was to investigate the tumor-suppressive activity and mechanism of a novel polysaccharide (SAP) extracted from Sarcodon aspratus. METHODS: The SAP was extracted and purified using Sepharose CL-4B gel from S. aspratus. The cytotoxicity of SAP on cell lines was determined by MTT method. Cellular migration assays were implemented by using transwell plates. The apoptosis and mitochondrial membrane potential (Δψm) of Hela cells were analyzed by flow cytometry. The western blot was used to determine the protein expression of Hela cells. RESULTS: The results showed that SAP with a molecular weight of 9.01×105 Da could significantly inhibit the growth of Hela cells in vitro. Three-dimensional cell culture (3D) and transwell assays showed that SAP restrained the multi-cellular spheroids growth and cell migration. Flow cytometry analysis revealed that SAP induced a loss of mitochondrial membrane potential (Δψm). Western blot assays indicated that SAP promoted the release of cytochrome c, increased Bax expression, down-regulated of Bcl-2 expression and activated of caspase-3 expression. CONCLUSION: This study suggested that SAP induced Hela cells apoptosis via mitochondrial dysfunction that are critical in events of caspase apoptotic pathways. The anti-tumor (Hela cells) activity of SAP recommended that S. aspratus could be used as a powerful medicinal mushroom against cancer.

Nondestructive and intuitive determination of circadian chlorophyll rhythms in soybean leaves using multispectral imaging.

The circadian clock, synchronized by daily cyclic environmental cues, regulates diverse aspects of plant growth and development and increases plant fitness. Even though much is known regarding the molecular mechanism of circadian clock, it remains challenging to quantify the temporal variation of major photosynthesis products as well as their metabolic output in higher plants in a real-time, nondestructive and intuitive manner. In order to reveal the spatial-temporal scenarios of photosynthesis and yield formation regulated by circadian clock, multispectral imaging technique has been employed for nondestructive determination of circadian chlorophyll rhythms in soybean leaves. By utilizing partial least square regression analysis, the determination coefficients R(2), 0.9483 for chlorophyll a and 0.8906 for chlorophyll b, were reached, respectively. The predicted chlorophyll contents extracted from multispectral data showed an approximately 24-h rhythm which could be entrained by external light conditions, consistent with the chlorophyll contents measured by chemical analyses. Visualization of chlorophyll map in each pixel offers an effective way to analyse spatial-temporal distribution of chlorophyll. Our results revealed the potentiality of multispectral imaging as a feasible nondestructive universal assay for examining clock function and robustness, as well as monitoring chlorophyll a and b and other biochemical components in plants.

Effect of BPA on the germination, root development, seedling growth and leaf differentiation under different light conditions in Arabidopsis thaliana.

Bisphenol A (BPA) is a well-known environmental toxic substance, which exerts unfavorable effects through endocrine disruptor (ER)-dependent and ER-independent mechanisms to threaten ecological systems seriously. BPA may also interact with other environmental factors, such as light and heavy metals, to have a synergetic effect in plants. However, there is little data concerning the toxic effect of BPA on the primary producers-plants and its possible interaction with light-dependent response. Here, the effects of BPA on germination, fresh weight, tap root length, and leaf differentiation were studied in Arabidopsis thaliana under different parts of light spectrum (dark, red, yellow, green, blue, and white light). Our results showed that low-dose BPA (1.0, 5.0 µM) caused an increase in the fresh weight, the tap root length and the lateral root formation of A. thaliana seedlings, while high-dose BPA (10.0, 25.0 µM) show an inhibition effect in a dose-dependent manner. Unlike karrikins, the effects of BPA on germination fresh weight and tap roots length under various light conditions are similar, which imply that BPA has no notable role in priming light response in germination and early seedling growth in A. thaliana. Meanwhile, BPA exposure influences the differentiation of A. thaliana leaf blade significantly in a light-dependent manner with little to no effect in dark and clear effect under red illumination.

Supercritical carbon dioxide extraction of the Oak Silkworm (Antheraea pernyi) Pupal Oil: process optimization and composition determination.

Supercritical carbon dioxide (SC-CO(2)) extraction of oil from oak silkworm pupae was performed in the present research. Response surface methodology (RSM) was applied to optimize the parameters of SC-CO(2) extraction, including extraction pressure, temperature, time and CO(2) flow rate on the yield of oak silkworm pupal oil (OSPO). The optimal extraction condition for oil yield within the experimental range of the variables researched was at 28.03 MPa, 1.83 h, 35.31 °C and 20.26 L/h as flow rate of CO(2). Under this condition, the oil yield was predicted to be 26.18%. The oak silkworm pupal oil contains eight fatty acids, and is rich in unsaturated fatty acids and α-linolenic acid (ALA), accounting for 77.29% and 34.27% in the total oil respectively.