Anti-fatigue activity of a Lachnum polysaccharide and its carboxymethylated derivative in mice.

The present study was designed to evaluate the anti-fatigue activity of an exopolysaccharide LEP-1b and its carboxymethylated derivative CLEP-1b from a Lachnum sp. Carboxymethylation was confirmed through FT-IR and 13C NMR spectroscopies, which showed that the (-CH2COOH) group was attached to an oxygen (O) atom of the hydroxyl group on (C-3) of LEP-1b. Each treatment group LEP-1b and CLEP-1b at doses (50, 100, 200mg/kg, respectively) ameliorated physical fatigue and extended exhaustive swimming time in mice. Results of the fatigue related biochemical markers showed that LEP-1b and CLEP-1b at doses (50, 100, 200mg/kg, respectively) increased the content of hepatic glycogen and decreased the level of serum urea nitrogen and lactic acid. Additionally, LEP-1b and CLEP-1b enhanced the antioxidant enzymes' activities and reduced the lipid peroxidation. Moreover, results revealed that CLEP-1b had higher anti-fatigue activity than LEP-1b at same doses but without statistical significance, especially CLEP-1b (200mg/kg) had strong anti-fatigue effects. Therefore, LEP-1b and CLEP-1b can potentially be exploited as a kind of healthcare compound to combat fatigue and to boost physical strength.

Anticoagulant activity of a sulfated Lachnum polysaccharide in mice with a state of hypercoagulability.

A sulfated polysaccharide, designated as SLEP-1, was obtained after sulfation of the exopolysaccharide (LEP-1) which was isolated from Lachnum. The degree of substitution (DS) of sulfate group of SLEP-1 was 1.97. SEM images of SLEP-1 revealed laminated structure in mesh. UV, FT-IR and 13C NMR spectra indicated that the LEP-1 was sulfated successfully. The result of the anticoagulant activity in vitro showed that both of LEP-1 and SLEP-1 could effectively prolong activated partial thromboplastin time (APTT) and thrombin time (TT) of the normal mice plasma, in which SLEP-1 was more effectively than those of LEP-1, and dose-effect relationships were found. According to the bleeding time (BT), clotting time (CT), APTT, PT, prothrombin time (TT), fibrinogen (FIB), AT-III activity and FXa concentration of the hypercoagulable mice, it indicated that SLEP-1 (30mg·kg-1 and 90mg·kg-1) had strong inhibitory effect on intrinsic coagulation pathway, which could also enhance fibrinolytic activity. It may constitute an anticoagulant drug of interest in anticoagulant therapy.

Protective effects of a Lachnum polysaccharide against liver and kidney injury induced by lead exposure in mice.

This study was designed to investigate the liver and kidney protective efficacy of a Lachnum polysaccharide (LEP) against Pb-induced toxicity in mice. The results showed that LEP decreased the Pb-induced bodyweight loss and organ index. Moreover, biochemical analysis showed that treatment of LEP could improve antioxidant status (CAT, GSH-Px and MDA) and the injury of tissues (liver and kidney). In addition, the histopathological observations indicated that LEP could attenuate liver and kidney cell injury induced by Pb. For further studies, key proteins involved in hepatic and kidney apoptosis, including cleaved caspase-3, Bax, Bcl-2, TGF-ß1 and α-SMA, were quantified. The present findings demonstrated that LEP is strongly effective in protecting against the liver and kidney injury induced by Pb. We hope this research can offer a theoretical base for development of polysaccharide based on nutraceutical food in future.

Antihyperlipidemic and hepatoprotective properties of selenium modified polysaccharide from Lachnum sp.

Hyperlipidemia is one of the major health problem people suffering throughout the world, which is also a major risk factor for chronic heart disease that can lead to death. The current study was designed to investigate antihyperlipidemic and hepatoprotective effects of selenium modified exopolysaccharide of Lachnum sp. (SeLEP-1b) on high-fat induced mice model. Nitric acid-sodium selenite (HNO3-Na2SeO3) method was used to selenize pure LEP-1b. FT-IR and 13C NMR results confirmed the modification of LEP-1b into SeLEP-1b. The main structure of SeLEP-1b was similar to the original structure of native LEP-1b and Se(O)OH group was attached to the O-6 position of C-6 in LEP-1b. Oral administration of LEP-1b and SeLEP-1b (200mg/kg) notably reduced the serum and liver lipids, atherogenic index, and enhanced the activities of antioxidant enzymes of hyperlipidemic mice, aswell improved the histopathological status of hepatic tissues. Hence, SeLEP-1b showed better effects than LEP-1b at the same doses. SeLEP-1b demonstrated promising lipid-lowering and liver protecting activities, which may be considered as a novel compound to treat hyperlipidemia and also act as a hepatoprotective agent.

Preparation, characterization and bioactivities of derivatives of an exopolysaccharide from Lachnum.

An exopolysaccharide, obtained previously LEP-2b from Lachnum YM405, was phosphated and sulfated successfully. The derivatives named PLEP-2b and SLEP-2b, respectively, and their respective degree of substitution were 0.174 and 0.431. Phosphate groups -PO3H2 substituted at C-6 of 1,4-ß-D-mannopyranose, C-5 of 2,6-ß-d-1-OMe-mannofuranoside, C-3 of 1,6-ß-D-galactopyranose, C-2 of 1-ß-D-glucopyranose, and C-6 of 1,2-α-D-rhampyranose, while sulfate groups SO3H were mainly at C-6 of 1,4-ß-D-Manp, C-6 of 1-ß-D-Glcp and C-6 of 1,2-α-D-Rhap. Compared with LEP-2b, the scavenging effects of the derivatives, on hydroxyl radical and superoxide anion were significantly increased after the modifications, except for reducing power. Meanwhile, phosphorylated and sulfated modifications remarkably strengthened the inhibiting effect of LEP-2b on the proliferation of CT-26 murine colon carcinoma, Lewis lung carcinoma and human hepatocellular carcinoma HepG2 cells. The derivatives significantly enhanced the antioxidant and antitumor activities in vitro. Compared with sulfation, phosphorylation improved the inhibitory effect more contraposingly on some specific tumor cells.

Carboxymethylation of an exopolysaccharide from Lachnum and effect of its derivatives on experimental chronic renal failure.

Carboxymethylated polysaccharide CLEP-1b was prepared from a single component (LEP-1b) of Lachnum YM281 exopolysaccharides by molecular modification with a degree of substitution (DS) of 0.286. Infrared result proved that the carboxymethylation of LEP-1b succeeded and (13)C NMR result showed that the carboxymethyl group (CH2COOH) was chemically linked to an oxygen (O) atom of the hydroxyl on C-3 of LEP-1b. LEP-1b could improve the histopathological status of kidney and significantly reduce the contents of serum creatinine (Scr) and blood urea nitrogen (BUN), and increase the contents of total protein and albumin. It could also enhance the activity of SOD, GSH-PX, CAT, GSH and decrease MDA contents in the nephridial and hepatic tissues. What's more, CLEP-1b showed more significant effects than LEP-1b at the same dosage. The research indicated that LEP-1b and CLEP-1b could mitigate the chronic renal failure of mice and the effects were closely associated with antioxidant activity.