Structural Elucidation of a Novel Polysaccharide from Pseudostellaria heterophylla and Stimulating Glucose Uptake in Cells and Distributing in Rats by Oral

Abstract

Abstract:The semi-refined polysaccharide of Pseudostellaria heterophylla is a complex polysaccharide that exhibits significantly hypoglycemic activities. A novel homogeneous polysaccharide, named as H-1-2, was isolated from the semi-refined polysaccharide. The mean molecular weight of H-1-2 was 1.4 × 10 4 Da and it was only composed of D-glucose monosaccharide. Structure elucidation indicated that H-1-2 contains pyranride, and has the characteristics of the α-iso-head configuration, a non-reducing end (T-), 4-, 1,6-, and 1,4,6-connection, in all four ways to connect glucose. H-1-2 was a type of glucan, where chemical combination exists in the main chain between 1→4 linked glucose, and contains a small amount of 1,6-linked glucose, which was in the branched chain. In vitro HepG2, 3T3-L1, and L6 cells were used to assess cellular glucose consumption and cellular glucose uptake by glucose oxidase, and the transport of 2-NBDG fluorescence probe results showed that H-1-2 could clearly increase glucose uptake and utilization in muscle and adipose cells, which is beneficial to screen for in the discovery of anti-diabetes lead compounds. H-1-2 was labeled with radioisotopes ( 99m Tc-pertechnetate). 99m Tc-labeled-H-1-2 was performed by SPECT/CT analysis images after oral administration in rats. At 4 h post ingestion, about 50% of the radioactivity was observed in the intestine. No significant radioactivity was found in the heart, liver, and kidney, conjecturing that absorption of 99m Tc-labeled H-1-2 might, via intestinal mucosa, be absorbed into systemic circulation. This problem, as to whether the polysaccharide is absorbed orally, will need further examination.

Investigation of the transport and absorption of Angelica sinensis polysaccharide through gastrointestinal tract both in vitro and in vivo

“…For instance, Zuo et al used the fluorescence FITC labeled squid ink polysaccharide to trace its transportation through the Caco-2 cells monolayer (Zuo et al, 2016). Chen et al reported that 99m Tc-labeled H-1-2 (Pseudostellaria heterophylla polysaccharide) was used for SPECT/CT studies to investigate the distribution of H-1-2 in mice after oral administration (Chen et al, 2016). Lee et al employed a near infrared fluorescent dye Cy5.5 labeled ZnO nanoparticles for near-infrared fluorescence imaging to investigate the behavior and biodistribution of the marker in mice after oral exposure (Lee et al, 2012).…”

Purification, Characterization, and Antioxidant Activity of Polysaccharides Isolated from Cortex Periplocae

“…HPGPC equipped with refractive index detector is considered a powerful, effective, and reliable technique to determine the purity and molecular properties of polysaccharides. The HPGPC elution profiles of CPP1, CPP2, and CPP3 had single and symmetrically sharp peaks ( Figure 2 ), which indicated the polysaccharides were homogeneous [ 18 , 19 , 20 ]. Based on the published literature, single and symmetrically sharp peaks can be obtained through HPGPC analysis [ 19 , 20 ], though some of the peaks were not perfect [ 18 , 21 ].…”

“…The HPGPC elution profiles of CPP1, CPP2, and CPP3 had single and symmetrically sharp peaks ( Figure 2 ), which indicated the polysaccharides were homogeneous [ 18 , 19 , 20 ]. Based on the published literature, single and symmetrically sharp peaks can be obtained through HPGPC analysis [ 19 , 20 ], though some of the peaks were not perfect [ 18 , 21 ]. Researchers have accepted the results because the polysaccharides were mixtures of various degrees of polymerization, which made them difficult to obtain very homogeneous components.…”

Novel Polysaccharide H-1-2 from Pseudostellaria Heterophylla Alleviates Type 2 Diabetes Mellitus

“…Here we exploited the potential therapeutic value of the novel identified polysaccharide H-1-2, which was isolated from the traditional Chinese medicine pseudostellaria heterophylla and implicated in improvement of glucose uptake [15], against T2DM with related disease animal model. We first consolidated the previous observations that hypoxia response was activated in T2DM milieu [17] and the corresponding down-regulation of Sirt1.…”