Effects of a combined fucoidan and traditional Chinese medicine formula on hyperglycaemia and diabetic nephropathy in a type II diabetes mellitus rat model.

In this study, we innovatively propose a fucoidan mixed with traditional Chinese medicine formula (FCM) and evaluate its effects on hyperglycaemia and diabetic nephropathy in a type II diabetes mellitus Wistar rat model. After treatment with FCM for 8 weeks, the blood glucose, insulin resistance, serum lipid and antioxidant stress levels were significantly decreased (P < 0.05 or P < 0.01, vs. negative group). Via gene expression analysis, we found that three genes (InsR, GCK and GLUT-2) in the glucose metabolism pathway were significantly increased (P < 0.01, vs. negative group) in the FCM-treated groups and play important roles in hypoglycaemic activity. Moreover, FCM treatments alleviated (P < 0.01, vs. negative group) the urine protein, urine creatinine and pathological changes in the kidneys, producing significant improvements in renal function and structure. In summary, FCM exerts protective effects in diabetic rats and could be used in medicinal treatment for diabetes mellitus and its complications.

In vitro and in vivo immunomodulatory effects of fucoidan compound agents.

Fucoidan extracted from brown algae displays diverse biological activities. In the present study, fucoidan was mixed with Chinese herb extracts, and the in vitro and in vivo immunomodulatory effects of two fucoidan compound agents were evaluated. The results showed that fucoidan from Kjellmaniella crassifolia (KF) and Undaria pinnatifida (UF) were sulfated polysaccharides, Astragalus polysaccharide (AP) was composed of α-d-glucose, and Codonopsis pilosula polysaccharide (CPP) was a furanose. Furthermore, fucoidan compound agents stimulated mouse macrophage RAW264.7 cell proliferation and enhanced the secretion of granulocyte-macrophage colony stimulating factor (GM-CSF) and tumour necrosis factor-α (TNF-α) in vitro. In addition, KCA (KF + AP + CPP) and UCA (UF + AP + CPP) could improve the nonspecific immunity and the specific immunity of BALB/c mice. Fucoidan compound agents also increased the secretion of GM-CSF, TNF-α, interleukin (IL)-4 and IL-10 in vivo. Therefore, we confirmed that fucoidan compound agents have promise for development as supplementary immunopotentiators.

Novel antioxidative peptides from the protein hydrolysate of oysters (Crassostrea talienwhanensis).

The antioxidative activity of hydrolysate peptides from oysters (Crassostrea talienwhanensis) was investigated. After hydrolysis with subtilisin, the yields of the peptides that were soluble in trichloroacetic acid (TCA-soluble) and the antioxidant activities of the resulting hydrolysate were determined using an orthogonal design and a hydroxyl radical scavenging reaction. The hydrolysate was fractionated using Sephadex G-15 gel filtration chromatography, and the two resulting bioactive peptides were subsequently purified by RP-HPLC with a Kromasil C18 (ODS) column. The amino acid sequences were analyzed by nano-ESI-MS/MS. The critical reaction temperature, pH, hydrolysis time and enzyme-to-substrate (E/S) ratio were determined for the optimum hydrolysis with subtilisin, and the E/S ratio was found to be the most critical reaction condition. The amino acid sequences of the peptides (518 and 440 Da) were proline-valine-methionine-glycine-aspartic acid (PVMGA) and glutamine-histidine-glycine-valine (QHGV), respectively. These two novel peptides exhibited high antioxidative actions based on their hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities.