Structural Characterization, Simulated Digestion and Anti-Aging Activities of an Acidic Polysaccharide from Salvia Miltiorrhiza

Structural characterization and anti-fatigue mechanism based on the gut-muscle axis of a polysaccharide from Zingiber officinale

This study aimed to characterize the structure of polysaccharide ZOPA extracted from Zingiber officinale and its purified form (ZOPA-1), and to investigate their anti-fatigue mechanisms based on the gut-muscle axis. The study found that the backbone of ZOPA-1 is primarily composed of →3,4)-α-Glcp-1→ and →4,6)-α-Glcp-(1→ linkages, with →4)-α-Glcp(1→ serving as its side chain. In exhaustive swimming experiments with mice, both crude ZOPA and purified ZOPA-1 demonstrated significant anti-fatigue effects, including enhanced glycogen storage, improved antioxidant capacity, reduced accumulation of metabolic waste products, and regulated energy metabolism in the gastrocnemius muscles. These effects may be mediated through the activation of the Keap1-Nrf2/ARE and AMPK/PGC-1α signaling pathways. Furthermore, ZOPA and ZOPA-1 modulated the intestinal flora of mice, increasing diversity, altering abundance, and regulating short-chain fatty acid concentrations, suggesting a potential role of the gut-muscle axis in mediating the anti-fatigue effects. This study provides valuable insights into the complex interplay between polysaccharides, the gut-muscle axis, and exercise-induced fatigue.

Xiyangshen Sanqi Danshen granules attenuated D-gal-induced C57BL/6J mouse aging through the AMPK/SIRT1 signaling pathway

BACKGROUND

Aging is a pressing global concern and is frequently accompanied by the emergence of many chronic diseases. Xiyangshen Sanqi Danshen granules (XSD) have antioxidant, anti-inflammatory and anti-fatigue functions, but the mechanism of their anti-aging effects is not clear.

METHODS

This study elucidated the anti-aging mechanism and potentially active ingredients of XSD by performing transcriptomic analysis and network pharmacological analysis in a D-galactose (D-gal)-induced C57BL/6J mouse aging model.

RESULTS

XSD improved learning and memory abilities while enhanced motor function in D-gal-induced aging mice, as shown by Morris water maze, passive avoidance test, and rotating rod test results. Additionally, XSD significantly increased the vascular pulse wave velocity (PWV), β-stiffness index and pressure strain elastic coefficient (EP), decreased carotid distensibility (CD) and decreased the expression levels of P53 and 8-OHdG in the common carotid arteries of D-gal mice. Transcriptome sequencing analysis identified that the AMPK/SIRT1 signaling pathway is the potential mechanism by which XSD attenuates aging. XSD also increased the protein levels of Ki67, AMPK, SIRT1 and the nuclear translocation of Nrf2 while decreased the protein levels of P21, P53, IL-18, 8-OHdG, nitrotyrosine, and COX-2 and the nuclear translocation of NF-κB p65 in the brains of D-gal-induced mice. The administration of the AMPK inhibitor and SIRT1 inhibitor hindered the anti-aging effect of XSD, as indicated by an elevation of 8-OHdG, COX-2, and nuclear translocation of NF-κB p65 ; and a decrease of Ki67 and the nuclear translocation of Nrf2. Network pharmacological analysis revealed that the potential active ingredients of XSD were quercetin, kaempferol, tanshinone IIA, isorhamnetin, ginsenoside F2, and cryptotanshinone.

CONCLUSION

Collectively, XSD mitigated D-gal-induced aging in C57BL/6J mice through enhancing the AMPK/SIRT1 signaling pathway. This research provides potential drugs for anti-aging and also promotes the usage of the anti-aging effect of XSD.

Structural Analysis and Novel Mechanism of Enteromorpha prolifera Sulfated Polysaccharide in Preventing Type 2 Diabetes Mellitus

A water-soluble polysaccharide (EP) was purified from edible algae Enteromorpha prolifera. Gel permeation chromatography (GPC), ion chromatography (IC), and fourier transform infrared (FT-IR) were performed to characterize its structure. EP was defined as a low molecular weight (6625 Da) composed of rhamnose, glucose, glucuronic acid, xylose, galactose, arabinose, and mannose. Moreover, it was a sulfated polysaccharide with a degree of substitution (DS) of 1.48. Then, the high-fat diet/streptozotocin (HFD/STZ) induced diabetic mouse model was established to support evidence for a novel hypoglycemic mechanism. Results showed that blood glucose (47.32%), liver index (7.65%), epididymal fat index (16.86%), serum total cholesterol (26.78%) and triglyceride (37.61%) in the high-dose EP (HEP) group were significantly lower than those in the HFD group. Noticeably, the content of liver glycogen in the HEP group was significantly higher (62.62%) than that in the HFD group, indicating the promotion of glycogen synthesis. These beneficial effects were attributed to significantly increased protein kinase B (AKT) phosphorylation and its downstream signaling response. Further studies showed that diabetic mice exhibited excessive O-GlcNAcylation level and high expression of O-linked β-D-N-acetylglucosamine transferase (OGT), which were decreased by 62.21 and 30.43% in the HEP group. This result suggested that EP had a similar effect to OGT inhibitors, which restored AKT phosphorylation and prevented pathoglycemia. This work reveals a novel hypoglycemic mechanism of EP, providing a theoretical basis for further studies on its pharmacological properties in improvement of T2DM.

Ultrasound-assisted hydrogen peroxide-ascorbic acid method to degrade sweet corncob polysaccharides can help treat type 2 diabetes via multiple pathways in vivo

In this study, we aimed to investigate the impact of various ultrasound durations on the structure and bioactivity of sweet corncob polysaccharides treated with ultrasound-assisted degradation using hydrogen peroxide and ascorbic acid (H2O2-Vc). We subjected sweet corncob polysaccharides to ultrasound treatment for 0, 30, 60, and 90 min alongside the H2O2-Vc method. We then analyzed their chemical composition and structure. Additionally, we administered these polysaccharides to mice with type 2 diabetes (T2DM) through gavage at a dosage of 200 mg/kg/day. The results indicated a significant reduction in the molecular weight of the degraded sweet corncob polysaccharides, while their composition remained relatively stable. However, the basic structure of the polysaccharides was retained. In vivo experiments demonstrated that ultrasound-assisted degradation of these polysaccharides had a positive impact on T2DM, particularly the 60-minute ultrasound treatment (UH-DSCBP-60 min), which effectively controlled blood glucose levels by regulating glycolipid metabolism in the livers of mice with T2DM. This approach also reduced inflammation and oxidative stress levels and inhibited disaccharide activity in the small intestine. We demonstrated that ultrasound can positively affect the sweet corncob polysaccharides hypoglycemic activity. The findings of our study provide a theoretical foundation for the valuable utilization of sweet corncob polysaccharides.