Extraction, purification, characteristics, bioactivities, prospects, and toxicity of Lilium spp. polysaccharides.

The genus Lilium has been widely used worldwide as a food and medicinal ingredient in East Asia for over 2000 years due to its higher nutritional and medicinal value. Polysaccharide is the most important bioactive ingredient in Lilium spp. and has various health benefits. Recently, Lilium spp. polysaccharides (LSPs) have attracted significant attention from industries and researchers due to their various biological properties, such as antioxidant, immunomodulatory, antitumor, antibacterial, hypoglycaemic, and anti-radiation. However, the development and utilization of LSP-based functional biomaterials and medicines are limited by a lack of comprehensive understanding regarding the structure-activity relationships (SARs), industrial applications, and safety of LSPs. This review provides an inclusive overview of the extraction, purification, structural features, bioactivities, and mechanisms of LSPs. SARs, applications, toxicities, and influences of structural modifications on bioactivities are also highlighted, and the potential development and future study direction are scrutinized. This article aims to offer a complete understanding of LSPs and provide a foundation for further research and application of LSPs as therapeutic agents and multifunctional biomaterials.

Extraction, structural-activity relationships, bioactivities, and application prospects of Bletilla striata polysaccharides as ingredients for functional products: A review.

Bletilla striata is a well-known medicinal plant with high pharmaceutical and ornamental values. Polysaccharide is the most important bioactive ingredient in B. striata and has various health benefits. Recently, B. striata polysaccharides (BSPs) have attracted much attention from industries and researchers due to their remarkable immunomodulatory, antioxidant, anti-cancer, hemostatic, anti-inflammatory, anti-microbial, gastroprotective, and liver protective effects. Despite the successful isolation and characterization of BSPs, there is still limited knowledge regarding their structure-activity relationships (SARs), safety concerns, and applications, which hinders their full utilization and development. Herein, we provided an overview of the extraction, purification, and structural features, as well as the effects of different influencing factors on the components and structures of BSPs. We also highlighted and summarized the diversity of chemistry and structure, specificity of biological activity, and SARs of BSP. The challenges and opportunities of BSPs in the food, pharmaceutical, and cosmeceutical fields are discussed, and the potential development and future study direction are scrutinized. This article provides comprehensive knowledge and underpinnings for further research and application of BSPs as therapeutic agents and multifunctional biomaterials.

Dihydromyricetin improves type 2 diabetes-induced cognitive impairment via suppressing oxidative stress and enhancing brain-derived neurotrophic factor-mediated neuroprotection in mice.

Type 2 diabetes mellitus (T2DM) leads to cognitive impairment (CI), but there have been no effective pharmacotherapies or drugs for cognitive dysfunction in T2DM. Dihydromyricetin (DHM) is a natural flavonoid compound extracted from the leaves of Ampelopsis grossedentata and has various pharmacological effects including anti-oxidant and anti-diabetes. Thus, we investigated the effects of DHM on CI in T2DM mouse model and its possible mechanism. To induce T2DM, mice were fed with high-sugar and high-fat diet for 8 weeks, followed by a low dose streptozotocin (STZ) administration. After the successful induction of T2DM mouse model, mice were treated respectively with equal volume of saline (T2DM group), 125 mg/kg/d DHM (L-DHM group), or 250 mg/kg/d DHM (H-DHM group). After 16 weeks of DHM administration, the body weight (BW), fasting blood glucose, blood lipids, intraperitoneal glucose tolerance (IPGT), and cognitive function were determined. Then, alterations in the expressions of oxidative stress markers and brain-derived neurotrophic factor (BDNF) in the hippocampus were investigated. Our findings demonstrated that DHM could significantly ameliorate CI and reverse aberrant glucose and lipid metabolism in T2DM mice, likely through the suppression of oxidative stress and enhancement of BDNF-mediated neuroprotection. In conclusion, our results suggest that DHM is a promising candidate for the treatment of T2DM-induced cognitive dysfunction.

[Ameliorative effects and the mechanism of lyceum barbarum polysaccharide on insulin resistance of HepG2 cell].

OBJECTIVE: To observe the effects of lyceum barbarum polysaccharide (LBP) on insulin resistance of HepG2 cells and investigate its possible mechanism. METHODS: IR-HepG2 cell model was induced with high glucose and high insulin in combination for 24 hours,with 104/vaccination in the 96-well plates, hole density after adherent cells (30 µg/ml、100 µg/ml、300 µg/ml) LBP cultivate 48 h, 200 µl/hole, each all had four holes. The effects of LBP at different concentrations on HepG2 cell activity and insulin resistance were tested. Intracellular malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were detected. The expressions of related proteins in insulin signal transduction pathways such as insulin receptor substrate-2(IRS-2), phosphatidylinositol-3-kinase(PI3-K), protein kinase B(Akt) and glucose transport-2(GLUT2) were determined. RESULTS: Compared with normal control group, the content of MDA was increased significantly and the activity of SOD and the expression levels of IRS-2,PI-3K,Akt and GLUT2 were decreased significantly in the IR model group. Compared with IR model group, medium and high concentrations of LBP decreased the content of MDA and increased the activity of SOD and the expression levels of IRS-2, PI-3K, Akt and GLUT2 in insulin-resistant HepG2 cells. MTT showed that at the same time, the OD value gradually decreased with the increase of LBP's concentration; under the same concentration of LBP, the OD value also gradually decreased with the extension of time, which indicated that LBP inhibited the proliferation of HepG2 cells with time and concentration-dependent manner. Glucose consumption experiment indicated that medium and high concentration of LBP could increase the glucose consumption of insulin-resistant HepG2 cells significantly, but low concentration of LBP had no significant impacted on glucose consumption of insulin-resistant HepG2 cells. CONCLUSIONS: Medium and high concentration of LBP can improve insulin resistance of HepG2 cell, its mechanisns may be associated with decreasing the level of oxidative stress and increasing the protein expressions of insulin signaling pathway.