Novel Fusion Protein Consisting of Metallothionein, Cellulose Binding Module, and Superfolder GFP for Lead Removal from the Water Decoction of Traditional Chinese Medicine.

Many methods have been used to detect heavy metals in herbal medicines, while few are developed to remove them. In this study, a novel genetically engineered fusion protein composed of metallothionein (MT), cellulose binding module (CBM), and superfolder GFP (sfGFP) was designed to remove heavy metals. MT, a kind of cysteine-rich protein, was used to chelate heavy metals with high specific affinity. The CBM facilitated the fusion protein MT-CBM-sfGFP binding to cellulose specifically, which made the purification and immobilization in one step. The sfGFP was used to detect the fusion protein MT-CBM-sfGFP easily during the process of expression and immobilization. The MT from Cancer pagurus (MTCap) and the CBM from Cellulomonas fimi (CBMCef) were used as an example and the fusion protein (MTCap-CBMCef-sfGFP) was expressed in Escherichia coli. Then, the cell lysates were mechanically mixed with cellulose to create biosorbent MTCap-CBMCef-sfGFP@cellulose. The efficiency of the biosorbent MTCap-CBMCef-sfGFP@cellulose for Pb2+ removal was evaluated using the water decoction of Honeysuckle as a model. Results suggested that MTCap-CBMCef-sfGFP@cellulose had high efficiency for Pb2+ removal from the water decoction of Honeysuckle without affecting its active ingredients. The low-cost, easy production, and high efficiency of the biosorbent enable it to have many applications in heavy metal removal from aqueous solutions of herbal medicines and food.

Structure of a pectic polysaccharide from Pseudostellaria heterophylla and stimulating insulin secretion of INS-1 cell and distributing in rats by oral.

A water-soluble, pectic polysaccharide named as 0.5MSC-F isolated from Pseudostellaria Heterophylla with a molecular weight of 4.8×104Da that was composed of rhamnose, galactose, arabinose, and galacturonic acid which the major monosaccharide contents range up to 63.20%. Where the main chain was consists of 1,4-linked galacturonic acid and a small amount of 1,2-linked rhamnose was embedded into backbone to connect alternative galacturonic acid in the form of Rhamnogalacturonan I (RG-I) structure. 1, 5-linked arabinose through C-4 of 1, 2-linked rhamnose, another 1, 3 or 1,6-linked galactose through C-4 of 1, 2-linked rhamnose, was interconnected to branch chain. 0.5MSC-F could obviously stimulated insulin secretion of islet cells cultured in high glucose are of potential practical value in the hypoglycemic action. Radioisotopes 99mTc-labeled-0.5MSC-F was analyzed by SPECT/CT image after oral in rats. At 2h post ingestion, above 40% of the radioactivity was observed in the intestine, but no found in the heart, liver, and kidney. Conjecturing absorption of 99mTc-labeled 0.5MSC-F might via intestinal mucosa absorption into the systemic circulation.

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

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 × 104 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.

Neuroprotective effects of salidroside on focal cerebral ischemia/reperfusion injury involve the nuclear erythroid 2-related factor 2 pathway.

Salidroside, the main active ingredient extracted from Rhodiola crenulata, has been shown to be neuroprotective in ischemic cerebral injury, but the underlying mechanism for this neuroprotection is poorly understood. In the current study, the neuroprotective effect of salidroside on cerebral ischemia-induced oxidative stress and the role of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway was investigated in a rat model of middle cerebral artery occlusion. Salidroside (30 mg/kg) reduced infarct size, improved neurological function and histological changes, increased activity of superoxide dismutase and glutathione-S-transferase, and reduced malon-dialdehyde levels after cerebral ischemia and reperfusion. Furthermore, salidroside apparently increased Nrf2 and heme oxygenase-1 expression. These results suggest that salidroside exerts its neuroprotective effect against cerebral ischemia through anti-oxidant mechanisms and that activation of the Nrf2 pathway is involved. The Nrf2/antioxidant response element pathway may become a new therapeutic target for the treatment of ischemic stroke.

A split G-quadruplex and graphene oxide-based low-background platform for fluorescence authentication of Pseudostellaria heterophylla.

A label-free split G-quadruplex and graphene oxide (GO)-based fluorescence platform has been designed to distinguish Pseudostellaria heterophylla (PH) from its adulterants based on the differences in their nrDNA ITS sequences. Herein, GO has been first introduced to capture G-rich probes with 2:2 split mode and then decrease the background signal. As T-DNA exists, the probes leave the GO surface to form double-stranded structures followed by the formation of the overhanging G-rich sequence into a G-quadruplex structure, which combines quinaldine red specifically to produce a strong fluorescence signal. In addition, this strategy allows detection of T-DNA in a wide range of concentrations from 1.0 × 10(-8) to 2.0 × 10(-6) mol·L(-1) with a detection limit of 7.8 × 10(-9) mol·L(-1). We hope that the split G-quadruplex/GO platform can be utilized to further develop gene identification sensors in Traditional Chinese Medicine or other analysis areas.